diff --git a/g10/getkey.c b/g10/getkey.c index 908d78595..cfcf9c96a 100644 --- a/g10/getkey.c +++ b/g10/getkey.c @@ -1,4322 +1,4322 @@ /* getkey.c - Get a key from the database * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, * 2007, 2008, 2010 Free Software Foundation, Inc. * Copyright (C) 2015, 2016 g10 Code GmbH * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include #include #include #include #include #include "gpg.h" #include "../common/util.h" #include "packet.h" #include "../common/iobuf.h" #include "keydb.h" #include "options.h" #include "main.h" #include "trustdb.h" #include "../common/i18n.h" #include "keyserver-internal.h" #include "call-agent.h" #include "objcache.h" #include "../common/host2net.h" #include "../common/mbox-util.h" #include "../common/status.h" #define MAX_PK_CACHE_ENTRIES PK_UID_CACHE_SIZE #define MAX_UID_CACHE_ENTRIES PK_UID_CACHE_SIZE #if MAX_PK_CACHE_ENTRIES < 2 #error We need the cache for key creation #endif /* Flags values returned by the lookup code. Note that the values are * directly used by the KEY_CONSIDERED status line. */ #define LOOKUP_NOT_SELECTED (1<<0) #define LOOKUP_ALL_SUBKEYS_EXPIRED (1<<1) /* or revoked */ /* A context object used by the lookup functions. */ struct getkey_ctx_s { /* Part of the search criteria: whether the search is an exact search or not. A search that is exact requires that a key or subkey meet all of the specified criteria. A search that is not exact allows selecting a different key or subkey from the keyblock that matched the criteria. Further, an exact search returns the key or subkey that matched whereas a non-exact search typically returns the primary key. See finish_lookup for details. */ int exact; /* Part of the search criteria: Whether the caller only wants keys with an available secret key. This is used by getkey_next to get the next result with the same initial criteria. */ int want_secret; /* Part of the search criteria: The type of the requested key. A mask of PUBKEY_USAGE_SIG, PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT. If non-zero, then for a key to match, it must implement one of the required uses. */ int req_usage; /* The database handle. */ KEYDB_HANDLE kr_handle; /* Whether we should call xfree() on the context when the context is released using getkey_end()). */ int not_allocated; /* This variable is used as backing store for strings which have their address used in ITEMS. */ strlist_t extra_list; /* Hack to return the mechanism (AKL_foo) used to find the key. */ int found_via_akl; /* Part of the search criteria: The low-level search specification as passed to keydb_search. */ int nitems; /* This must be the last element in the structure. When we allocate the structure, we allocate it so that ITEMS can hold NITEMS. */ KEYDB_SEARCH_DESC items[1]; }; #if 0 static struct { int any; int okay_count; int nokey_count; int error_count; } lkup_stats[21]; #endif typedef struct keyid_list { struct keyid_list *next; byte fprlen; char fpr[MAX_FINGERPRINT_LEN]; u32 keyid[2]; } *keyid_list_t; #if MAX_PK_CACHE_ENTRIES typedef struct pk_cache_entry { struct pk_cache_entry *next; u32 keyid[2]; PKT_public_key *pk; } *pk_cache_entry_t; static pk_cache_entry_t pk_cache; static int pk_cache_entries; /* Number of entries in pk cache. */ static int pk_cache_disabled; #endif #if MAX_UID_CACHE_ENTRIES < 5 #error we really need the userid cache #endif static void merge_selfsigs (ctrl_t ctrl, kbnode_t keyblock); static int lookup (ctrl_t ctrl, getkey_ctx_t ctx, int want_secret, kbnode_t *ret_keyblock, kbnode_t *ret_found_key); static kbnode_t finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact, int want_secret, unsigned int *r_flags); static void print_status_key_considered (kbnode_t keyblock, unsigned int flags); #if 0 static void print_stats () { int i; for (i = 0; i < DIM (lkup_stats); i++) { if (lkup_stats[i].any) es_fprintf (es_stderr, "lookup stats: mode=%-2d ok=%-6d nokey=%-6d err=%-6d\n", i, lkup_stats[i].okay_count, lkup_stats[i].nokey_count, lkup_stats[i].error_count); } } #endif /* Cache a copy of a public key in the public key cache. PK is not * cached if caching is disabled (via getkey_disable_caches), if * PK->FLAGS.DONT_CACHE is set, we don't know how to derive a key id * from the public key (e.g., unsupported algorithm), or a key with * the key id is already in the cache. * * The public key packet is copied into the cache using * copy_public_key. Thus, any secret parts are not copied, for * instance. * * This cache is filled by get_pubkey and is read by get_pubkey and * get_pubkey_fast. */ void cache_public_key (PKT_public_key * pk) { #if MAX_PK_CACHE_ENTRIES pk_cache_entry_t ce, ce2; u32 keyid[2]; if (pk_cache_disabled) return; if (pk->flags.dont_cache) return; if (is_ELGAMAL (pk->pubkey_algo) || pk->pubkey_algo == PUBKEY_ALGO_DSA || pk->pubkey_algo == PUBKEY_ALGO_ECDSA || pk->pubkey_algo == PUBKEY_ALGO_EDDSA || pk->pubkey_algo == PUBKEY_ALGO_ECDH || is_RSA (pk->pubkey_algo)) { keyid_from_pk (pk, keyid); } else return; /* Don't know how to get the keyid. */ for (ce = pk_cache; ce; ce = ce->next) if (ce->keyid[0] == keyid[0] && ce->keyid[1] == keyid[1]) { if (DBG_CACHE) log_debug ("cache_public_key: already in cache\n"); return; } if (pk_cache_entries >= MAX_PK_CACHE_ENTRIES) { int n; /* Remove the last 50% of the entries. */ for (ce = pk_cache, n = 0; ce && n < pk_cache_entries/2; n++) ce = ce->next; if (ce && ce != pk_cache && ce->next) { ce2 = ce->next; ce->next = NULL; ce = ce2; for (; ce; ce = ce2) { ce2 = ce->next; free_public_key (ce->pk); xfree (ce); pk_cache_entries--; } } log_assert (pk_cache_entries < MAX_PK_CACHE_ENTRIES); } pk_cache_entries++; ce = xmalloc (sizeof *ce); ce->next = pk_cache; pk_cache = ce; ce->pk = copy_public_key (NULL, pk); ce->keyid[0] = keyid[0]; ce->keyid[1] = keyid[1]; #endif } /* Return a const utf-8 string with the text "[User ID not found]". This function is required so that we don't need to switch gettext's encoding temporary. */ static const char * user_id_not_found_utf8 (void) { static char *text; if (!text) text = native_to_utf8 (_("[User ID not found]")); return text; } /* Disable and drop the public key cache (which is filled by cache_public_key and get_pubkey). Note: there is currently no way to re-enable this cache. */ void getkey_disable_caches () { #if MAX_PK_CACHE_ENTRIES { pk_cache_entry_t ce, ce2; for (ce = pk_cache; ce; ce = ce2) { ce2 = ce->next; free_public_key (ce->pk); xfree (ce); } pk_cache_disabled = 1; pk_cache_entries = 0; pk_cache = NULL; } #endif /* fixme: disable user id cache ? */ } /* Free a list of pubkey_t objects. */ void pubkeys_free (pubkey_t keys) { while (keys) { pubkey_t next = keys->next; xfree (keys->pk); release_kbnode (keys->keyblock); xfree (keys); keys = next; } } static void pk_from_block (PKT_public_key *pk, kbnode_t keyblock, kbnode_t found_key) { kbnode_t a = found_key ? found_key : keyblock; log_assert (a->pkt->pkttype == PKT_PUBLIC_KEY || a->pkt->pkttype == PKT_PUBLIC_SUBKEY); copy_public_key (pk, a->pkt->pkt.public_key); } /* Specialized version of get_pubkey which retrieves the key based on * information in SIG. In contrast to get_pubkey PK is required. IF * FORCED_PK is not NULL, this public key is used and copied to PK. */ gpg_error_t get_pubkey_for_sig (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig, PKT_public_key *forced_pk) { const byte *fpr; size_t fprlen; if (forced_pk) { copy_public_key (pk, forced_pk); return 0; } - /* First try the new ISSUER_FPR info. */ + /* First try the ISSUER_FPR info. */ fpr = issuer_fpr_raw (sig, &fprlen); if (fpr && !get_pubkey_byfprint (ctrl, pk, NULL, fpr, fprlen)) return 0; /* Fallback to use the ISSUER_KEYID. */ return get_pubkey (ctrl, pk, sig->keyid); } /* Return the public key with the key id KEYID and store it at PK. * The resources in *PK should be released using * release_public_key_parts(). This function also stores a copy of * the public key in the user id cache (see cache_public_key). * * If PK is NULL, this function just stores the public key in the * cache and returns the usual return code. * * PK->REQ_USAGE (which is a mask of PUBKEY_USAGE_SIG, * PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT) is passed through to the * lookup function. If this is non-zero, only keys with the specified * usage will be returned. As such, it is essential that * PK->REQ_USAGE be correctly initialized! * * Returns 0 on success, GPG_ERR_NO_PUBKEY if there is no public key * with the specified key id, or another error code if an error * occurs. * * If the data was not read from the cache, then the self-signed data * has definitely been merged into the public key using * merge_selfsigs. */ int get_pubkey (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid) { int internal = 0; int rc = 0; #if MAX_PK_CACHE_ENTRIES if (pk) { /* Try to get it from the cache. We don't do this when pk is NULL as it does not guarantee that the user IDs are cached. */ pk_cache_entry_t ce; for (ce = pk_cache; ce; ce = ce->next) { if (ce->keyid[0] == keyid[0] && ce->keyid[1] == keyid[1]) /* XXX: We don't check PK->REQ_USAGE here, but if we don't read from the cache, we do check it! */ { copy_public_key (pk, ce->pk); return 0; } } } #endif /* More init stuff. */ if (!pk) { internal++; pk = xtrycalloc (1, sizeof *pk); if (!pk) { rc = gpg_error_from_syserror (); goto leave; } } /* Do a lookup. */ { struct getkey_ctx_s ctx; kbnode_t kb = NULL; kbnode_t found_key = NULL; memset (&ctx, 0, sizeof ctx); ctx.exact = 1; /* Use the key ID exactly as given. */ ctx.not_allocated = 1; if (ctrl && ctrl->cached_getkey_kdb) { ctx.kr_handle = ctrl->cached_getkey_kdb; ctrl->cached_getkey_kdb = NULL; keydb_search_reset (ctx.kr_handle); } else { ctx.kr_handle = keydb_new (ctrl); if (!ctx.kr_handle) { rc = gpg_error_from_syserror (); goto leave; } } ctx.nitems = 1; ctx.items[0].mode = KEYDB_SEARCH_MODE_LONG_KID; ctx.items[0].u.kid[0] = keyid[0]; ctx.items[0].u.kid[1] = keyid[1]; ctx.req_usage = pk->req_usage; rc = lookup (ctrl, &ctx, 0, &kb, &found_key); if (!rc) { pk_from_block (pk, kb, found_key); } getkey_end (ctrl, &ctx); release_kbnode (kb); } if (!rc) goto leave; rc = GPG_ERR_NO_PUBKEY; leave: if (!rc) cache_public_key (pk); if (internal) free_public_key (pk); return rc; } /* Similar to get_pubkey, but it does not take PK->REQ_USAGE into * account nor does it merge in the self-signed data. This function * also only considers primary keys. It is intended to be used as a * quick check of the key to avoid recursion. It should only be used * in very certain cases. Like get_pubkey and unlike any of the other * lookup functions, this function also consults the user id cache * (see cache_public_key). * * Return the public key in *PK. The resources in *PK should be * released using release_public_key_parts(). */ int get_pubkey_fast (ctrl_t ctrl, PKT_public_key * pk, u32 * keyid) { int rc = 0; KEYDB_HANDLE hd; KBNODE keyblock; u32 pkid[2]; log_assert (pk); #if MAX_PK_CACHE_ENTRIES { /* Try to get it from the cache */ pk_cache_entry_t ce; for (ce = pk_cache; ce; ce = ce->next) { if (ce->keyid[0] == keyid[0] && ce->keyid[1] == keyid[1] /* Only consider primary keys. */ && ce->pk->keyid[0] == ce->pk->main_keyid[0] && ce->pk->keyid[1] == ce->pk->main_keyid[1]) { if (pk) copy_public_key (pk, ce->pk); return 0; } } } #endif hd = keydb_new (ctrl); if (!hd) return gpg_error_from_syserror (); rc = keydb_search_kid (hd, keyid); if (gpg_err_code (rc) == GPG_ERR_NOT_FOUND) { keydb_release (hd); return GPG_ERR_NO_PUBKEY; } rc = keydb_get_keyblock (hd, &keyblock); keydb_release (hd); if (rc) { log_error ("keydb_get_keyblock failed: %s\n", gpg_strerror (rc)); return GPG_ERR_NO_PUBKEY; } log_assert (keyblock && keyblock->pkt && keyblock->pkt->pkttype == PKT_PUBLIC_KEY); /* We return the primary key. If KEYID matched a subkey, then we return an error. */ keyid_from_pk (keyblock->pkt->pkt.public_key, pkid); if (keyid[0] == pkid[0] && keyid[1] == pkid[1]) copy_public_key (pk, keyblock->pkt->pkt.public_key); else rc = GPG_ERR_NO_PUBKEY; release_kbnode (keyblock); /* Not caching key here since it won't have all of the fields properly set. */ return rc; } /* Return the entire keyblock used to create SIG. This is a * specialized version of get_pubkeyblock. * * FIXME: This is a hack because get_pubkey_for_sig was already called * and it could have used a cache to hold the key. */ kbnode_t get_pubkeyblock_for_sig (ctrl_t ctrl, PKT_signature *sig) { const byte *fpr; size_t fprlen; kbnode_t keyblock; - /* First try the new ISSUER_FPR info. */ + /* First try the ISSUER_FPR info. */ fpr = issuer_fpr_raw (sig, &fprlen); if (fpr && !get_pubkey_byfprint (ctrl, NULL, &keyblock, fpr, fprlen)) return keyblock; /* Fallback to use the ISSUER_KEYID. */ return get_pubkeyblock (ctrl, sig->keyid); } /* Return the key block for the key with key id KEYID or NULL, if an * error occurs. Use release_kbnode() to release the key block. * * The self-signed data has already been merged into the public key * using merge_selfsigs. */ kbnode_t get_pubkeyblock (ctrl_t ctrl, u32 * keyid) { struct getkey_ctx_s ctx; int rc = 0; KBNODE keyblock = NULL; memset (&ctx, 0, sizeof ctx); /* No need to set exact here because we want the entire block. */ ctx.not_allocated = 1; ctx.kr_handle = keydb_new (ctrl); if (!ctx.kr_handle) return NULL; ctx.nitems = 1; ctx.items[0].mode = KEYDB_SEARCH_MODE_LONG_KID; ctx.items[0].u.kid[0] = keyid[0]; ctx.items[0].u.kid[1] = keyid[1]; rc = lookup (ctrl, &ctx, 0, &keyblock, NULL); getkey_end (ctrl, &ctx); return rc ? NULL : keyblock; } /* Return the public key with the key id KEYID iff the secret key is * available and store it at PK. The resources should be released * using release_public_key_parts(). * * Unlike other lookup functions, PK may not be NULL. PK->REQ_USAGE * is passed through to the lookup function and is a mask of * PUBKEY_USAGE_SIG, PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT. Thus, it * must be valid! If this is non-zero, only keys with the specified * usage will be returned. * * Returns 0 on success. If a public key with the specified key id is * not found or a secret key is not available for that public key, an * error code is returned. Note: this function ignores legacy keys. * An error code is also return if an error occurs. * * The self-signed data has already been merged into the public key * using merge_selfsigs. */ gpg_error_t get_seckey (ctrl_t ctrl, PKT_public_key *pk, u32 *keyid) { gpg_error_t err; struct getkey_ctx_s ctx; kbnode_t keyblock = NULL; kbnode_t found_key = NULL; memset (&ctx, 0, sizeof ctx); ctx.exact = 1; /* Use the key ID exactly as given. */ ctx.not_allocated = 1; ctx.kr_handle = keydb_new (ctrl); if (!ctx.kr_handle) return gpg_error_from_syserror (); ctx.nitems = 1; ctx.items[0].mode = KEYDB_SEARCH_MODE_LONG_KID; ctx.items[0].u.kid[0] = keyid[0]; ctx.items[0].u.kid[1] = keyid[1]; ctx.req_usage = pk->req_usage; err = lookup (ctrl, &ctx, 1, &keyblock, &found_key); if (!err) { pk_from_block (pk, keyblock, found_key); } getkey_end (ctrl, &ctx); release_kbnode (keyblock); if (!err) { if (!agent_probe_secret_key (/*ctrl*/NULL, pk)) { release_public_key_parts (pk); err = gpg_error (GPG_ERR_NO_SECKEY); } } return err; } /* Skip unusable keys. A key is unusable if it is revoked, expired or disabled or if the selected user id is revoked or expired. */ static int skip_unusable (void *opaque, u32 * keyid, int uid_no) { ctrl_t ctrl = opaque; int unusable = 0; KBNODE keyblock; PKT_public_key *pk; keyblock = get_pubkeyblock (ctrl, keyid); if (!keyblock) { log_error ("error checking usability status of %s\n", keystr (keyid)); goto leave; } pk = keyblock->pkt->pkt.public_key; /* Is the key revoked or expired? */ if (pk->flags.revoked || pk->has_expired) unusable = 1; /* Is the user ID in question revoked or expired? */ if (!unusable && uid_no) { KBNODE node; int uids_seen = 0; for (node = keyblock; node; node = node->next) { if (node->pkt->pkttype == PKT_USER_ID) { PKT_user_id *user_id = node->pkt->pkt.user_id; uids_seen ++; if (uids_seen != uid_no) continue; if (user_id->flags.revoked || user_id->flags.expired) unusable = 1; break; } } /* If UID_NO is non-zero, then the keyblock better have at least that many UIDs. */ log_assert (uids_seen == uid_no); } if (!unusable) unusable = pk_is_disabled (pk); leave: release_kbnode (keyblock); return unusable; } /* Search for keys matching some criteria. If RETCTX is not NULL, then the constructed context is returned in *RETCTX so that getpubkey_next can be used to get subsequent results. In this case, getkey_end() must be used to free the search context. If RETCTX is not NULL, then RET_KDBHD must be NULL. If NAMELIST is not NULL, then a search query is constructed using classify_user_id on each of the strings in the list. (Recall: the database does an OR of the terms, not an AND.) If NAMELIST is NULL, then all results are returned. If PK is not NULL, the public key of the first result is returned in *PK. Note: PK->REQ_USAGE must be valid!!! If PK->REQ_USAGE is set, it is used to filter the search results. See the documentation for finish_lookup to understand exactly how this is used. Note: The self-signed data has already been merged into the public key using merge_selfsigs. Free *PK by calling release_public_key_parts (or, if PK was allocated using xfree, you can use free_public_key, which calls release_public_key_parts(PK) and then xfree(PK)). If WANT_SECRET is set, then only keys with an available secret key (either locally or via key registered on a smartcard) are returned. If INCLUDE_UNUSABLE is set, then unusable keys (see the documentation for skip_unusable for an exact definition) are skipped unless they are looked up by key id or by fingerprint. If RET_KB is not NULL, the keyblock is returned in *RET_KB. This should be freed using release_kbnode(). If RET_KDBHD is not NULL, then the new database handle used to conduct the search is returned in *RET_KDBHD. This can be used to get subsequent results using keydb_search_next. Note: in this case, no advanced filtering is done for subsequent results (e.g., WANT_SECRET and PK->REQ_USAGE are not respected). This function returns 0 on success. Otherwise, an error code is returned. In particular, GPG_ERR_NO_PUBKEY or GPG_ERR_NO_SECKEY (if want_secret is set) is returned if the key is not found. */ static int key_byname (ctrl_t ctrl, GETKEY_CTX *retctx, strlist_t namelist, PKT_public_key *pk, int want_secret, int include_unusable, KBNODE * ret_kb, KEYDB_HANDLE * ret_kdbhd) { int rc = 0; int n; strlist_t r; strlist_t namelist_expanded = NULL; GETKEY_CTX ctx; KBNODE help_kb = NULL; KBNODE found_key = NULL; if (retctx) { /* Reset the returned context in case of error. */ log_assert (!ret_kdbhd); /* Not allowed because the handle is stored in the context. */ *retctx = NULL; } if (ret_kdbhd) *ret_kdbhd = NULL; if (!namelist) /* No search terms: iterate over the whole DB. */ { ctx = xmalloc_clear (sizeof *ctx); ctx->nitems = 1; ctx->items[0].mode = KEYDB_SEARCH_MODE_FIRST; if (!include_unusable) { ctx->items[0].skipfnc = skip_unusable; ctx->items[0].skipfncvalue = ctrl; } } else { namelist_expanded = expand_group (namelist, 1); namelist = namelist_expanded; /* Build the search context. */ for (n = 0, r = namelist; r; r = r->next) n++; /* CTX has space for a single search term at the end. Thus, we need to allocate sizeof *CTX plus (n - 1) sizeof CTX->ITEMS. */ ctx = xmalloc_clear (sizeof *ctx + (n - 1) * sizeof ctx->items); ctx->nitems = n; for (n = 0, r = namelist; r; r = r->next, n++) { gpg_error_t err; err = classify_user_id (r->d, &ctx->items[n], 1); if (ctx->items[n].exact) ctx->exact = 1; if (err) { xfree (ctx); rc = gpg_err_code (err); /* FIXME: remove gpg_err_code. */ goto leave; } if (!include_unusable && ctx->items[n].mode != KEYDB_SEARCH_MODE_SHORT_KID && ctx->items[n].mode != KEYDB_SEARCH_MODE_LONG_KID && ctx->items[n].mode != KEYDB_SEARCH_MODE_FPR) { ctx->items[n].skipfnc = skip_unusable; ctx->items[n].skipfncvalue = ctrl; } } } ctx->want_secret = want_secret; ctx->kr_handle = keydb_new (ctrl); if (!ctx->kr_handle) { rc = gpg_error_from_syserror (); getkey_end (ctrl, ctx); goto leave; } if (!ret_kb) ret_kb = &help_kb; if (pk) { ctx->req_usage = pk->req_usage; } rc = lookup (ctrl, ctx, want_secret, ret_kb, &found_key); if (!rc && pk) { pk_from_block (pk, *ret_kb, found_key); } release_kbnode (help_kb); if (retctx) /* Caller wants the context. */ { if (ctx->extra_list) { for (r=ctx->extra_list; r->next; r = r->next) ; r->next = namelist_expanded; } else ctx->extra_list = namelist_expanded; namelist_expanded = NULL; *retctx = ctx; } else { if (ret_kdbhd) { *ret_kdbhd = ctx->kr_handle; ctx->kr_handle = NULL; } getkey_end (ctrl, ctx); } leave: free_strlist (namelist_expanded); return rc; } /* Find a public key identified by NAME. * * If name appears to be a valid RFC822 mailbox (i.e., email address) * and auto key lookup is enabled (mode != GET_PUBKEY_NO_AKL), then * the specified auto key lookup methods (--auto-key-lookup) are used * to import the key into the local keyring. Otherwise, just the * local keyring is consulted. * * MODE can be one of: * GET_PUBKEY_NORMAL - The standard mode * GET_PUBKEY_NO_AKL - The auto key locate functionality is * disabled and only the local key ring is * considered. Note: the local key ring is * consulted even if local is not in the * auto-key-locate option list! * GET_PUBKEY_NO_LOCAL - Only the auto key locate functionality is * used and no local search is done. * * If RETCTX is not NULL, then the constructed context is returned in * *RETCTX so that getpubkey_next can be used to get subsequent * results. In this case, getkey_end() must be used to free the * search context. If RETCTX is not NULL, then RET_KDBHD must be * NULL. * * If PK is not NULL, the public key of the first result is returned * in *PK. Note: PK->REQ_USAGE must be valid!!! PK->REQ_USAGE is * passed through to the lookup function and is a mask of * PUBKEY_USAGE_SIG, PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT. If this * is non-zero, only keys with the specified usage will be returned. * Note: The self-signed data has already been merged into the public * key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xfree, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * NAME is a string, which is turned into a search query using * classify_user_id. * * If RET_KEYBLOCK is not NULL, the keyblock is returned in * *RET_KEYBLOCK. This should be freed using release_kbnode(). * * If RET_KDBHD is not NULL, then the new database handle used to * conduct the search is returned in *RET_KDBHD. This can be used to * get subsequent results using keydb_search_next or to modify the * returned record. Note: in this case, no advanced filtering is done * for subsequent results (e.g., PK->REQ_USAGE is not respected). * Unlike RETCTX, this is always returned. * * If INCLUDE_UNUSABLE is set, then unusable keys (see the * documentation for skip_unusable for an exact definition) are * skipped unless they are looked up by key id or by fingerprint. * * This function returns 0 on success. Otherwise, an error code is * returned. In particular, GPG_ERR_NO_PUBKEY or GPG_ERR_NO_SECKEY * (if want_secret is set) is returned if the key is not found. */ int get_pubkey_byname (ctrl_t ctrl, enum get_pubkey_modes mode, GETKEY_CTX * retctx, PKT_public_key * pk, const char *name, KBNODE * ret_keyblock, KEYDB_HANDLE * ret_kdbhd, int include_unusable) { int rc; strlist_t namelist = NULL; struct akl *akl; int is_mbox; int nodefault = 0; int anylocalfirst = 0; int mechanism_type = AKL_NODEFAULT; /* If RETCTX is not NULL, then RET_KDBHD must be NULL. */ log_assert (retctx == NULL || ret_kdbhd == NULL); if (retctx) *retctx = NULL; /* Does NAME appear to be a mailbox (mail address)? */ is_mbox = is_valid_mailbox (name); if (!is_mbox && *name == '<' && name[1] && name[strlen(name)-1]=='>' && name[1] != '>' && is_valid_mailbox_mem (name+1, strlen (name)-2)) { /* The mailbox is in the form "" which is not * detected by is_valid_mailbox. Set the flag but keep name as * it is because the bracketed name is actual the better * specification for a local search and the other methods * extract the mail address anyway. */ is_mbox = 1; } /* The auto-key-locate feature works as follows: there are a number * of methods to look up keys. By default, the local keyring is * tried first. Then, each method listed in the --auto-key-locate is * tried in the order it appears. * * This can be changed as follows: * * - if nodefault appears anywhere in the list of options, then * the local keyring is not tried first, or, * * - if local appears anywhere in the list of options, then the * local keyring is not tried first, but in the order in which * it was listed in the --auto-key-locate option. * * Note: we only save the search context in RETCTX if the local * method is the first method tried (either explicitly or * implicitly). */ if (mode == GET_PUBKEY_NO_LOCAL) nodefault = 1; /* Auto-key-locate but ignore "local". */ else if (mode != GET_PUBKEY_NO_AKL) { /* auto-key-locate is enabled. */ /* nodefault is true if "nodefault" or "local" appear. */ for (akl = opt.auto_key_locate; akl; akl = akl->next) if (akl->type == AKL_NODEFAULT || akl->type == AKL_LOCAL) { nodefault = 1; break; } /* anylocalfirst is true if "local" appears before any other search methods (except "nodefault"). */ for (akl = opt.auto_key_locate; akl; akl = akl->next) if (akl->type != AKL_NODEFAULT) { if (akl->type == AKL_LOCAL) anylocalfirst = 1; break; } } if (!nodefault) { /* "nodefault" didn't occur. Thus, "local" is implicitly the * first method to try. */ anylocalfirst = 1; } if (mode == GET_PUBKEY_NO_LOCAL) { /* Force using the AKL. If IS_MBOX is not set this is the final * error code. */ rc = GPG_ERR_NO_PUBKEY; } else if (nodefault && is_mbox) { /* Either "nodefault" or "local" (explicitly) appeared in the * auto key locate list and NAME appears to be an email address. * Don't try the local keyring. */ rc = GPG_ERR_NO_PUBKEY; } else { /* Either "nodefault" and "local" don't appear in the auto key * locate list (in which case we try the local keyring first) or * NAME does not appear to be an email address (in which case we * only try the local keyring). In this case, lookup NAME in * the local keyring. */ add_to_strlist (&namelist, name); rc = key_byname (ctrl, retctx, namelist, pk, 0, include_unusable, ret_keyblock, ret_kdbhd); } /* If the requested name resembles a valid mailbox and automatic retrieval has been enabled, we try to import the key. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && mode != GET_PUBKEY_NO_AKL && is_mbox) { /* NAME wasn't present in the local keyring (or we didn't try * the local keyring). Since the auto key locate feature is * enabled and NAME appears to be an email address, try the auto * locate feature. */ for (akl = opt.auto_key_locate; akl; akl = akl->next) { unsigned char *fpr = NULL; size_t fpr_len; int did_akl_local = 0; int no_fingerprint = 0; const char *mechanism_string = "?"; mechanism_type = akl->type; switch (mechanism_type) { case AKL_NODEFAULT: /* This is a dummy mechanism. */ mechanism_string = ""; rc = GPG_ERR_NO_PUBKEY; break; case AKL_LOCAL: if (mode == GET_PUBKEY_NO_LOCAL) { mechanism_string = ""; rc = GPG_ERR_NO_PUBKEY; } else { mechanism_string = "Local"; did_akl_local = 1; if (retctx) { getkey_end (ctrl, *retctx); *retctx = NULL; } add_to_strlist (&namelist, name); rc = key_byname (ctrl, anylocalfirst ? retctx : NULL, namelist, pk, 0, include_unusable, ret_keyblock, ret_kdbhd); } break; case AKL_CERT: mechanism_string = "DNS CERT"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_cert (ctrl, name, 0, &fpr, &fpr_len); glo_ctrl.in_auto_key_retrieve--; break; case AKL_PKA: mechanism_string = "PKA"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_pka (ctrl, name, &fpr, &fpr_len); glo_ctrl.in_auto_key_retrieve--; break; case AKL_DANE: mechanism_string = "DANE"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_cert (ctrl, name, 1, &fpr, &fpr_len); glo_ctrl.in_auto_key_retrieve--; break; case AKL_WKD: mechanism_string = "WKD"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_wkd (ctrl, name, 0, &fpr, &fpr_len); glo_ctrl.in_auto_key_retrieve--; break; case AKL_LDAP: mechanism_string = "LDAP"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_ldap (ctrl, name, &fpr, &fpr_len); glo_ctrl.in_auto_key_retrieve--; break; case AKL_KEYSERVER: /* Strictly speaking, we don't need to only use a valid * mailbox for the getname search, but it helps cut down * on the problem of searching for something like "john" * and getting a whole lot of keys back. */ if (keyserver_any_configured (ctrl)) { mechanism_string = "keyserver"; glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_name (ctrl, name, &fpr, &fpr_len, opt.keyserver); glo_ctrl.in_auto_key_retrieve--; } else { mechanism_string = "Unconfigured keyserver"; rc = GPG_ERR_NO_PUBKEY; } break; case AKL_SPEC: { struct keyserver_spec *keyserver; mechanism_string = akl->spec->uri; keyserver = keyserver_match (akl->spec); glo_ctrl.in_auto_key_retrieve++; rc = keyserver_import_name (ctrl, name, &fpr, &fpr_len, keyserver); glo_ctrl.in_auto_key_retrieve--; } break; } /* Use the fingerprint of the key that we actually fetched. * This helps prevent problems where the key that we fetched * doesn't have the same name that we used to fetch it. In * the case of CERT and PKA, this is an actual security * requirement as the URL might point to a key put in by an * attacker. By forcing the use of the fingerprint, we * won't use the attacker's key here. */ if (!rc && fpr) { char fpr_string[MAX_FINGERPRINT_LEN * 2 + 1]; log_assert (fpr_len <= MAX_FINGERPRINT_LEN); free_strlist (namelist); namelist = NULL; bin2hex (fpr, fpr_len, fpr_string); if (opt.verbose) log_info ("auto-key-locate found fingerprint %s\n", fpr_string); add_to_strlist (&namelist, fpr_string); } else if (!rc && !fpr && !did_akl_local) { /* The acquisition method said no failure occurred, but * it didn't return a fingerprint. That's a failure. */ no_fingerprint = 1; rc = GPG_ERR_NO_PUBKEY; } xfree (fpr); fpr = NULL; if (!rc && !did_akl_local) { /* There was no error and we didn't do a local lookup. * This means that we imported a key into the local * keyring. Try to read the imported key from the * keyring. */ if (retctx) { getkey_end (ctrl, *retctx); *retctx = NULL; } rc = key_byname (ctrl, anylocalfirst ? retctx : NULL, namelist, pk, 0, include_unusable, ret_keyblock, ret_kdbhd); } if (!rc) { /* Key found. */ if (opt.verbose) log_info (_("automatically retrieved '%s' via %s\n"), name, mechanism_string); break; } if ((gpg_err_code (rc) != GPG_ERR_NO_PUBKEY || opt.verbose || no_fingerprint) && *mechanism_string) log_info (_("error retrieving '%s' via %s: %s\n"), name, mechanism_string, no_fingerprint ? _("No fingerprint") : gpg_strerror (rc)); } } if (rc && retctx) { getkey_end (ctrl, *retctx); *retctx = NULL; } if (retctx && *retctx) { GETKEY_CTX ctx = *retctx; strlist_t sl; if (ctx->extra_list) { for (sl=ctx->extra_list; sl->next; sl = sl->next) ; sl->next = namelist; } else ctx->extra_list = namelist; (*retctx)->found_via_akl = mechanism_type; } else free_strlist (namelist); return rc; } /* Comparison machinery for get_best_pubkey_byname. */ /* First we have a struct to cache computed information about the key * in question. */ struct pubkey_cmp_cookie { int valid; /* Is this cookie valid? */ PKT_public_key key; /* The key. */ PKT_user_id *uid; /* The matching UID packet. */ unsigned int validity; /* Computed validity of (KEY, UID). */ u32 creation_time; /* Creation time of the newest subkey capable of encryption. */ }; /* Then we have a series of helper functions. */ static int key_is_ok (const PKT_public_key *key) { return (! key->has_expired && ! key->flags.revoked && key->flags.valid && ! key->flags.disabled); } static int uid_is_ok (const PKT_public_key *key, const PKT_user_id *uid) { return key_is_ok (key) && ! uid->flags.revoked; } static int subkey_is_ok (const PKT_public_key *sub) { return ! sub->flags.revoked && sub->flags.valid && ! sub->flags.disabled; } /* Return true if KEYBLOCK has only expired encryption subkyes. Note * that the function returns false if the key has no encryption * subkeys at all or the subkeys are revoked. */ static int only_expired_enc_subkeys (kbnode_t keyblock) { kbnode_t node; PKT_public_key *sub; int any = 0; for (node = find_next_kbnode (keyblock, PKT_PUBLIC_SUBKEY); node; node = find_next_kbnode (node, PKT_PUBLIC_SUBKEY)) { sub = node->pkt->pkt.public_key; if (!(sub->pubkey_usage & PUBKEY_USAGE_ENC)) continue; if (!subkey_is_ok (sub)) continue; any = 1; if (!sub->has_expired) return 0; } return any? 1 : 0; } /* Finally this function compares a NEW key to the former candidate * OLD. Returns < 0 if the old key is worse, > 0 if the old key is * better, == 0 if it is a tie. */ static int pubkey_cmp (ctrl_t ctrl, const char *name, struct pubkey_cmp_cookie *old, struct pubkey_cmp_cookie *new, KBNODE new_keyblock) { kbnode_t n; if ((new->key.pubkey_usage & PUBKEY_USAGE_ENC) == 0) new->creation_time = 0; else new->creation_time = new->key.timestamp; for (n = find_next_kbnode (new_keyblock, PKT_PUBLIC_SUBKEY); n; n = find_next_kbnode (n, PKT_PUBLIC_SUBKEY)) { PKT_public_key *sub = n->pkt->pkt.public_key; if ((sub->pubkey_usage & PUBKEY_USAGE_ENC) == 0) continue; if (! subkey_is_ok (sub)) continue; if (sub->timestamp > new->creation_time) new->creation_time = sub->timestamp; } /* When new key has no encryption key, use OLD key. */ if (new->creation_time == 0) return 1; for (n = find_next_kbnode (new_keyblock, PKT_USER_ID); n; n = find_next_kbnode (n, PKT_USER_ID)) { PKT_user_id *uid = n->pkt->pkt.user_id; char *mbox = mailbox_from_userid (uid->name, 0); int match = mbox ? strcasecmp (name, mbox) == 0 : 0; xfree (mbox); if (! match) continue; new->uid = scopy_user_id (uid); new->validity = get_validity (ctrl, new_keyblock, &new->key, uid, NULL, 0) & TRUST_MASK; new->valid = 1; if (! old->valid) return -1; /* No OLD key. */ if (! uid_is_ok (&old->key, old->uid) && uid_is_ok (&new->key, uid)) return -1; /* Validity of the NEW key is better. */ if (old->validity < new->validity) return -1; /* Validity of the NEW key is better. */ if (old->validity == new->validity && uid_is_ok (&new->key, uid) && old->creation_time < new->creation_time) return -1; /* Both keys are of the same validity, but the NEW key is newer. */ } /* Stick with the OLD key. */ return 1; } /* This function works like get_pubkey_byname, but if the name * resembles a mail address, the results are ranked and only the best * result is returned. */ gpg_error_t get_best_pubkey_byname (ctrl_t ctrl, enum get_pubkey_modes mode, GETKEY_CTX *retctx, PKT_public_key *pk, const char *name, KBNODE *ret_keyblock, int include_unusable) { gpg_error_t err; struct getkey_ctx_s *ctx = NULL; int is_mbox; int wkd_tried = 0; PKT_public_key pk0; log_assert (ret_keyblock != NULL); if (retctx) *retctx = NULL; memset (&pk0, 0, sizeof pk0); pk0.req_usage = pk? pk->req_usage : 0; is_mbox = is_valid_mailbox (name); if (!is_mbox && *name == '<' && name[1] && name[strlen(name)-1]=='>' && name[1] != '>' && is_valid_mailbox_mem (name+1, strlen (name)-2)) { /* The mailbox is in the form "" which is not * detected by is_valid_mailbox. Set the flag but keep name as * it is because get_pubkey_byname does an is_valid_mailbox_mem * itself. */ is_mbox = 1; } start_over: if (ctx) /* Clear in case of a start over. */ { release_kbnode (*ret_keyblock); *ret_keyblock = NULL; getkey_end (ctrl, ctx); ctx = NULL; } err = get_pubkey_byname (ctrl, mode, &ctx, &pk0, name, ret_keyblock, NULL, include_unusable); if (err) { goto leave; } /* If the keyblock was retrieved from the local database and the key * has expired, do further checks. However, we can do this only if * the caller requested a keyblock. */ if (is_mbox && ctx && ctx->found_via_akl == AKL_LOCAL) { u32 now = make_timestamp (); int found; /* If the key has expired and its origin was the WKD then try to * get a fresh key from the WKD. We also try this if the key * has any only expired encryption subkeys. In case we checked * for a fresh copy in the last 3 hours we won't do that again. * Unfortunately that does not yet work because KEYUPDATE is * only updated during import iff the key has actually changed * (see import.c:import_one). */ if (!wkd_tried && pk0.keyorg == KEYORG_WKD && (pk0.keyupdate + 3*3600) < now && (pk0.has_expired || only_expired_enc_subkeys (*ret_keyblock))) { if (opt.verbose) log_info (_("checking for a fresh copy of an expired key via %s\n"), "WKD"); wkd_tried = 1; glo_ctrl.in_auto_key_retrieve++; found = !keyserver_import_wkd (ctrl, name, 0, NULL, NULL); glo_ctrl.in_auto_key_retrieve--; if (found) { release_public_key_parts (&pk0); goto start_over; } } } if (is_mbox && ctx) { /* Rank results and return only the most relevant key for encryption. */ struct pubkey_cmp_cookie best = { 0 }; struct pubkey_cmp_cookie new = { 0 }; kbnode_t new_keyblock; copy_public_key (&new.key, &pk0); if (pubkey_cmp (ctrl, name, &best, &new, *ret_keyblock) >= 0) { release_public_key_parts (&new.key); free_user_id (new.uid); } else best = new; new.uid = NULL; while (getkey_next (ctrl, ctx, &new.key, &new_keyblock) == 0) { int diff = pubkey_cmp (ctrl, name, &best, &new, new_keyblock); release_kbnode (new_keyblock); if (diff < 0) { /* New key is better. */ release_public_key_parts (&best.key); free_user_id (best.uid); best = new; } else if (diff > 0) { /* Old key is better. */ release_public_key_parts (&new.key); free_user_id (new.uid); } else { /* A tie. Keep the old key. */ release_public_key_parts (&new.key); free_user_id (new.uid); } new.uid = NULL; } getkey_end (ctrl, ctx); ctx = NULL; free_user_id (best.uid); best.uid = NULL; if (best.valid) { ctx = xtrycalloc (1, sizeof **retctx); if (! ctx) err = gpg_error_from_syserror (); else { ctx->kr_handle = keydb_new (ctrl); if (! ctx->kr_handle) { err = gpg_error_from_syserror (); xfree (ctx); ctx = NULL; if (retctx) *retctx = NULL; } else { u32 *keyid = pk_keyid (&best.key); ctx->exact = 1; ctx->nitems = 1; ctx->items[0].mode = KEYDB_SEARCH_MODE_LONG_KID; ctx->items[0].u.kid[0] = keyid[0]; ctx->items[0].u.kid[1] = keyid[1]; release_kbnode (*ret_keyblock); *ret_keyblock = NULL; err = getkey_next (ctrl, ctx, NULL, ret_keyblock); } } if (pk) *pk = best.key; else release_public_key_parts (&best.key); release_public_key_parts (&pk0); } else { if (pk) *pk = pk0; else release_public_key_parts (&pk0); } } else { if (pk) *pk = pk0; else release_public_key_parts (&pk0); } if (err && ctx) { getkey_end (ctrl, ctx); ctx = NULL; } if (retctx && ctx) { *retctx = ctx; ctx = NULL; } leave: getkey_end (ctrl, ctx); return err; } /* Get a public key from a file. * * PK is the buffer to store the key. The caller needs to make sure * that PK->REQ_USAGE is valid. PK->REQ_USAGE is passed through to * the lookup function and is a mask of PUBKEY_USAGE_SIG, * PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT. If this is non-zero, only * keys with the specified usage will be returned. * * FNAME is the file name. That file should contain exactly one * keyblock. * * This function returns 0 on success. Otherwise, an error code is * returned. In particular, GPG_ERR_NO_PUBKEY is returned if the key * is not found. * * The self-signed data has already been merged into the public key * using merge_selfsigs. The caller must release the content of PK by * calling release_public_key_parts (or, if PK was malloced, using * free_public_key). */ gpg_error_t get_pubkey_fromfile (ctrl_t ctrl, PKT_public_key *pk, const char *fname) { gpg_error_t err; kbnode_t keyblock; kbnode_t found_key; unsigned int infoflags; err = read_key_from_file_or_buffer (ctrl, fname, NULL, 0, &keyblock); if (!err) { /* Warning: node flag bits 0 and 1 should be preserved by * merge_selfsigs. FIXME: Check whether this still holds. */ merge_selfsigs (ctrl, keyblock); found_key = finish_lookup (keyblock, pk->req_usage, 0, 0, &infoflags); print_status_key_considered (keyblock, infoflags); if (found_key) pk_from_block (pk, keyblock, found_key); else err = gpg_error (GPG_ERR_UNUSABLE_PUBKEY); } release_kbnode (keyblock); return err; } /* Return a public key from the buffer (BUFFER, BUFLEN). The key is * onlyretruned if it matches the keyid given in WANT_KEYID. On * success the key is stored at the caller provided PKBUF structure. * The caller must release the content of PK by calling * release_public_key_parts (or, if PKBUF was malloced, using * free_public_key). If R_KEYBLOCK is not NULL the full keyblock is * also stored there. */ gpg_error_t get_pubkey_from_buffer (ctrl_t ctrl, PKT_public_key *pkbuf, const void *buffer, size_t buflen, u32 *want_keyid, kbnode_t *r_keyblock) { gpg_error_t err; kbnode_t keyblock; kbnode_t node; PKT_public_key *pk; if (r_keyblock) *r_keyblock = NULL; err = read_key_from_file_or_buffer (ctrl, NULL, buffer, buflen, &keyblock); if (!err) { merge_selfsigs (ctrl, keyblock); for (node = keyblock; node; node = node->next) { if (node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_PUBLIC_SUBKEY) { pk = node->pkt->pkt.public_key; keyid_from_pk (pk, NULL); if (pk->keyid[0] == want_keyid[0] && pk->keyid[1] == want_keyid[1]) break; } } if (node) copy_public_key (pkbuf, pk); else err = gpg_error (GPG_ERR_NO_PUBKEY); } if (!err && r_keyblock) *r_keyblock = keyblock; else release_kbnode (keyblock); return err; } /* Lookup a key with the specified fingerprint. * * If PK is not NULL, the public key of the first result is returned * in *PK. Note: this function does an exact search and thus the * returned public key may be a subkey rather than the primary key. * Note: The self-signed data has already been merged into the public * key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xfree, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * If PK->REQ_USAGE is set, it is used to filter the search results. * (Thus, if PK is not NULL, PK->REQ_USAGE must be valid!!!) See the * documentation for finish_lookup to understand exactly how this is * used. * * If R_KEYBLOCK is not NULL, then the first result's keyblock is * returned in *R_KEYBLOCK. This should be freed using * release_kbnode(). * * FPRINT is a byte array whose contents is the fingerprint to use as * the search term. FPRINT_LEN specifies the length of the * fingerprint (in bytes). Currently, only 16, 20, and 32-byte * fingerprints are supported. * * FIXME: We should replace this with the _byname function. This can * be done by creating a userID conforming to the unified fingerprint * style. */ int get_pubkey_byfprint (ctrl_t ctrl, PKT_public_key *pk, kbnode_t *r_keyblock, const byte * fprint, size_t fprint_len) { int rc; if (r_keyblock) *r_keyblock = NULL; if (fprint_len == 32 || fprint_len == 20 || fprint_len == 16) { struct getkey_ctx_s ctx; KBNODE kb = NULL; KBNODE found_key = NULL; memset (&ctx, 0, sizeof ctx); ctx.exact = 1; ctx.not_allocated = 1; /* FIXME: We should get the handle from the cache like we do in * get_pubkey. */ ctx.kr_handle = keydb_new (ctrl); if (!ctx.kr_handle) return gpg_error_from_syserror (); ctx.nitems = 1; ctx.items[0].mode = KEYDB_SEARCH_MODE_FPR; memcpy (ctx.items[0].u.fpr, fprint, fprint_len); ctx.items[0].fprlen = fprint_len; if (pk) ctx.req_usage = pk->req_usage; rc = lookup (ctrl, &ctx, 0, &kb, &found_key); if (!rc && pk) pk_from_block (pk, kb, found_key); if (!rc && r_keyblock) { *r_keyblock = kb; kb = NULL; } release_kbnode (kb); getkey_end (ctrl, &ctx); } else rc = GPG_ERR_GENERAL; /* Oops */ return rc; } /* This function is similar to get_pubkey_byfprint, but it doesn't * merge the self-signed data into the public key and subkeys or into * the user ids. It also doesn't add the key to the user id cache. * Further, this function ignores PK->REQ_USAGE. * * This function is intended to avoid recursion and, as such, should * only be used in very specific situations. * * Like get_pubkey_byfprint, PK may be NULL. In that case, this * function effectively just checks for the existence of the key. */ gpg_error_t get_pubkey_byfprint_fast (ctrl_t ctrl, PKT_public_key * pk, const byte * fprint, size_t fprint_len) { gpg_error_t err; KBNODE keyblock; err = get_keyblock_byfprint_fast (ctrl, &keyblock, NULL, fprint, fprint_len, 0); if (!err) { if (pk) copy_public_key (pk, keyblock->pkt->pkt.public_key); release_kbnode (keyblock); } return err; } /* This function is similar to get_pubkey_byfprint_fast but returns a * keydb handle at R_HD and the keyblock at R_KEYBLOCK. R_KEYBLOCK or * R_HD may be NULL. If LOCK is set the handle has been opend in * locked mode and keydb_disable_caching () has been called. On error * R_KEYBLOCK is set to NULL but R_HD must be released by the caller; * it may have a value of NULL, though. This allows to do an insert * operation on a locked keydb handle. */ gpg_error_t get_keyblock_byfprint_fast (ctrl_t ctrl, kbnode_t *r_keyblock, KEYDB_HANDLE *r_hd, const byte *fprint, size_t fprint_len, int lock) { gpg_error_t err; KEYDB_HANDLE hd; kbnode_t keyblock; byte fprbuf[MAX_FINGERPRINT_LEN]; int i; if (r_keyblock) *r_keyblock = NULL; if (r_hd) *r_hd = NULL; for (i = 0; i < MAX_FINGERPRINT_LEN && i < fprint_len; i++) fprbuf[i] = fprint[i]; hd = keydb_new (ctrl); if (!hd) return gpg_error_from_syserror (); if (lock) { err = keydb_lock (hd); if (err) { /* If locking did not work, we better don't return a handle * at all - there was a reason that locking has been * requested. */ keydb_release (hd); return err; } keydb_disable_caching (hd); } /* For all other errors we return the handle. */ if (r_hd) *r_hd = hd; err = keydb_search_fpr (hd, fprbuf, fprint_len); if (gpg_err_code (err) == GPG_ERR_NOT_FOUND) { if (!r_hd) keydb_release (hd); return gpg_error (GPG_ERR_NO_PUBKEY); } err = keydb_get_keyblock (hd, &keyblock); if (err) { log_error ("keydb_get_keyblock failed: %s\n", gpg_strerror (err)); if (!r_hd) keydb_release (hd); return gpg_error (GPG_ERR_NO_PUBKEY); } log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY || keyblock->pkt->pkttype == PKT_PUBLIC_SUBKEY); /* Not caching key here since it won't have all of the fields properly set. */ if (r_keyblock) *r_keyblock = keyblock; else release_kbnode (keyblock); if (!r_hd) keydb_release (hd); return 0; } const char * parse_def_secret_key (ctrl_t ctrl) { KEYDB_HANDLE hd = NULL; strlist_t t; static int warned; for (t = opt.def_secret_key; t; t = t->next) { gpg_error_t err; KEYDB_SEARCH_DESC desc; KBNODE kb; KBNODE node; err = classify_user_id (t->d, &desc, 1); if (err) { log_error (_("secret key \"%s\" not found: %s\n"), t->d, gpg_strerror (err)); if (!opt.quiet) log_info (_("(check argument of option '%s')\n"), "--default-key"); continue; } if (! hd) { hd = keydb_new (ctrl); if (!hd) return NULL; } else keydb_search_reset (hd); err = keydb_search (hd, &desc, 1, NULL); if (gpg_err_code (err) == GPG_ERR_NOT_FOUND) continue; if (err) { log_error (_("key \"%s\" not found: %s\n"), t->d, gpg_strerror (err)); t = NULL; break; } err = keydb_get_keyblock (hd, &kb); if (err) { log_error (_("error reading keyblock: %s\n"), gpg_strerror (err)); continue; } merge_selfsigs (ctrl, kb); err = gpg_error (GPG_ERR_NO_SECKEY); node = kb; do { PKT_public_key *pk = node->pkt->pkt.public_key; /* Check if the key is valid. */ if (pk->flags.revoked) { if (DBG_LOOKUP) log_debug ("not using %s as default key, %s", keystr_from_pk (pk), "revoked"); continue; } if (pk->has_expired) { if (DBG_LOOKUP) log_debug ("not using %s as default key, %s", keystr_from_pk (pk), "expired"); continue; } if (pk_is_disabled (pk)) { if (DBG_LOOKUP) log_debug ("not using %s as default key, %s", keystr_from_pk (pk), "disabled"); continue; } if (agent_probe_secret_key (ctrl, pk)) { /* This is a valid key. */ err = 0; break; } } while ((node = find_next_kbnode (node, PKT_PUBLIC_SUBKEY))); release_kbnode (kb); if (err) { if (! warned && ! opt.quiet) { log_info (_("Warning: not using '%s' as default key: %s\n"), t->d, gpg_strerror (GPG_ERR_NO_SECKEY)); print_reported_error (err, GPG_ERR_NO_SECKEY); } } else { if (! warned && ! opt.quiet) log_info (_("using \"%s\" as default secret key for signing\n"), t->d); break; } } if (! warned && opt.def_secret_key && ! t) log_info (_("all values passed to '%s' ignored\n"), "--default-key"); warned = 1; if (hd) keydb_release (hd); if (t) return t->d; return NULL; } /* Look up a secret key. * * If PK is not NULL, the public key of the first result is returned * in *PK. Note: PK->REQ_USAGE must be valid!!! If PK->REQ_USAGE is * set, it is used to filter the search results. See the * documentation for finish_lookup to understand exactly how this is * used. Note: The self-signed data has already been merged into the * public key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xfree, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * If --default-key was set, then the specified key is looked up. (In * this case, the default key is returned even if it is considered * unusable. See the documentation for skip_unusable for exactly what * this means.) * * Otherwise, this initiates a DB scan that returns all keys that are * usable (see previous paragraph for exactly what usable means) and * for which a secret key is available. * * This function returns the first match. Additional results can be * returned using getkey_next. */ gpg_error_t get_seckey_default (ctrl_t ctrl, PKT_public_key *pk) { gpg_error_t err; strlist_t namelist = NULL; int include_unusable = 1; const char *def_secret_key = parse_def_secret_key (ctrl); if (def_secret_key) add_to_strlist (&namelist, def_secret_key); else include_unusable = 0; err = key_byname (ctrl, NULL, namelist, pk, 1, include_unusable, NULL, NULL); free_strlist (namelist); return err; } /* Search for keys matching some criteria. * * If RETCTX is not NULL, then the constructed context is returned in * *RETCTX so that getpubkey_next can be used to get subsequent * results. In this case, getkey_end() must be used to free the * search context. If RETCTX is not NULL, then RET_KDBHD must be * NULL. * * If PK is not NULL, the public key of the first result is returned * in *PK. Note: PK->REQ_USAGE must be valid!!! If PK->REQ_USAGE is * set, it is used to filter the search results. See the * documentation for finish_lookup to understand exactly how this is * used. Note: The self-signed data has already been merged into the * public key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xfree, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * If NAMES is not NULL, then a search query is constructed using * classify_user_id on each of the strings in the list. (Recall: the * database does an OR of the terms, not an AND.) If NAMES is * NULL, then all results are returned. * * If WANT_SECRET is set, then only keys with an available secret key * (either locally or via key registered on a smartcard) are returned. * * This function does not skip unusable keys (see the documentation * for skip_unusable for an exact definition). * * If RET_KEYBLOCK is not NULL, the keyblock is returned in * *RET_KEYBLOCK. This should be freed using release_kbnode(). * * This function returns 0 on success. Otherwise, an error code is * returned. In particular, GPG_ERR_NO_PUBKEY or GPG_ERR_NO_SECKEY * (if want_secret is set) is returned if the key is not found. */ gpg_error_t getkey_bynames (ctrl_t ctrl, getkey_ctx_t *retctx, PKT_public_key *pk, strlist_t names, int want_secret, kbnode_t *ret_keyblock) { return key_byname (ctrl, retctx, names, pk, want_secret, 1, ret_keyblock, NULL); } /* Search for one key matching some criteria. * * If RETCTX is not NULL, then the constructed context is returned in * *RETCTX so that getpubkey_next can be used to get subsequent * results. In this case, getkey_end() must be used to free the * search context. If RETCTX is not NULL, then RET_KDBHD must be * NULL. * * If PK is not NULL, the public key of the first result is returned * in *PK. Note: PK->REQ_USAGE must be valid!!! If PK->REQ_USAGE is * set, it is used to filter the search results. See the * documentation for finish_lookup to understand exactly how this is * used. Note: The self-signed data has already been merged into the * public key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xfree, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * If NAME is not NULL, then a search query is constructed using * classify_user_id on the string. In this case, even unusable keys * (see the documentation for skip_unusable for an exact definition of * unusable) are returned. Otherwise, if --default-key was set, then * that key is returned (even if it is unusable). If neither of these * conditions holds, then the first usable key is returned. * * If WANT_SECRET is set, then only keys with an available secret key * (either locally or via key registered on a smartcard) are returned. * * This function does not skip unusable keys (see the documentation * for skip_unusable for an exact definition). * * If RET_KEYBLOCK is not NULL, the keyblock is returned in * *RET_KEYBLOCK. This should be freed using release_kbnode(). * * This function returns 0 on success. Otherwise, an error code is * returned. In particular, GPG_ERR_NO_PUBKEY or GPG_ERR_NO_SECKEY * (if want_secret is set) is returned if the key is not found. * * FIXME: We also have the get_pubkey_byname function which has a * different semantic. Should be merged with this one. */ gpg_error_t getkey_byname (ctrl_t ctrl, getkey_ctx_t *retctx, PKT_public_key *pk, const char *name, int want_secret, kbnode_t *ret_keyblock) { gpg_error_t err; strlist_t namelist = NULL; int with_unusable = 1; const char *def_secret_key = NULL; if (want_secret && !name) def_secret_key = parse_def_secret_key (ctrl); if (want_secret && !name && def_secret_key) add_to_strlist (&namelist, def_secret_key); else if (name) add_to_strlist (&namelist, name); else with_unusable = 0; err = key_byname (ctrl, retctx, namelist, pk, want_secret, with_unusable, ret_keyblock, NULL); /* FIXME: Check that we really return GPG_ERR_NO_SECKEY if WANT_SECRET has been used. */ free_strlist (namelist); return err; } /* Return the next search result. * * If PK is not NULL, the public key of the next result is returned in * *PK. Note: The self-signed data has already been merged into the * public key using merge_selfsigs. Free *PK by calling * release_public_key_parts (or, if PK was allocated using xmalloc, you * can use free_public_key, which calls release_public_key_parts(PK) * and then xfree(PK)). * * RET_KEYBLOCK can be given as NULL; if it is not NULL it the entire * found keyblock is returned which must be released with * release_kbnode. If the function returns an error NULL is stored at * RET_KEYBLOCK. * * The self-signed data has already been merged into the public key * using merge_selfsigs. */ gpg_error_t getkey_next (ctrl_t ctrl, getkey_ctx_t ctx, PKT_public_key *pk, kbnode_t *ret_keyblock) { int rc; /* Fixme: Make sure this is proper gpg_error */ KBNODE keyblock = NULL; KBNODE found_key = NULL; /* We need to disable the caching so that for an exact key search we won't get the result back from the cache and thus end up in an endless loop. The endless loop can occur, because the cache is used without respecting the current file pointer! */ keydb_disable_caching (ctx->kr_handle); /* FOUND_KEY is only valid as long as RET_KEYBLOCK is. If the * caller wants PK, but not RET_KEYBLOCK, we need hand in our own * keyblock. */ if (pk && ret_keyblock == NULL) ret_keyblock = &keyblock; rc = lookup (ctrl, ctx, ctx->want_secret, ret_keyblock, pk ? &found_key : NULL); if (!rc && pk) { log_assert (found_key); pk_from_block (pk, NULL, found_key); release_kbnode (keyblock); } return rc; } /* Release any resources used by a key listing context. This must be * called on the context returned by, e.g., getkey_byname. */ void getkey_end (ctrl_t ctrl, getkey_ctx_t ctx) { if (ctx) { #ifdef HAVE_W32_SYSTEM /* FIXME: This creates a big regression for Windows because the * keyring is only released after the global ctrl is released. * So if an operation does a getkey and then tries to modify the * keyring it will fail on Windows with a sharing violation. We * need to modify all keyring write operations to also take the * ctrl and close the cached_getkey_kdb handle to make writing * work. See: GnuPG-bug-id: 3097 */ (void)ctrl; keydb_release (ctx->kr_handle); #else /*!HAVE_W32_SYSTEM*/ if (ctrl && !ctrl->cached_getkey_kdb) ctrl->cached_getkey_kdb = ctx->kr_handle; else keydb_release (ctx->kr_handle); #endif /*!HAVE_W32_SYSTEM*/ free_strlist (ctx->extra_list); if (!ctx->not_allocated) xfree (ctx); } } /************************************************ ************* Merging stuff ******************** ************************************************/ /* Set the mainkey_id fields for all keys in KEYBLOCK. This is * usually done by merge_selfsigs but at some places we only need the * main_kid not a full merge. The function also guarantees that all * pk->keyids are computed. */ void setup_main_keyids (kbnode_t keyblock) { u32 kid[2], mainkid[2]; kbnode_t kbctx, node; PKT_public_key *pk; if (keyblock->pkt->pkttype != PKT_PUBLIC_KEY) BUG (); pk = keyblock->pkt->pkt.public_key; keyid_from_pk (pk, mainkid); for (kbctx=NULL; (node = walk_kbnode (keyblock, &kbctx, 0)); ) { if (!(node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_PUBLIC_SUBKEY)) continue; pk = node->pkt->pkt.public_key; keyid_from_pk (pk, kid); /* Make sure pk->keyid is set. */ if (!pk->main_keyid[0] && !pk->main_keyid[1]) { pk->main_keyid[0] = mainkid[0]; pk->main_keyid[1] = mainkid[1]; } } } /* KEYBLOCK corresponds to a public key block. This function merges * much of the information from the self-signed data into the public * key, public subkey and user id data structures. If you use the * high-level search API (e.g., get_pubkey) for looking up key blocks, * then you don't need to call this function. This function is * useful, however, if you change the keyblock, e.g., by adding or * removing a self-signed data packet. */ void merge_keys_and_selfsig (ctrl_t ctrl, kbnode_t keyblock) { if (!keyblock) ; else if (keyblock->pkt->pkttype == PKT_PUBLIC_KEY) merge_selfsigs (ctrl, keyblock); else log_debug ("FIXME: merging secret key blocks is not anymore available\n"); } static int parse_key_usage (PKT_signature * sig) { int key_usage = 0; const byte *p; size_t n; byte flags; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_KEY_FLAGS, &n); if (p && n) { /* First octet of the keyflags. */ flags = *p; if (flags & 1) { key_usage |= PUBKEY_USAGE_CERT; flags &= ~1; } if (flags & 2) { key_usage |= PUBKEY_USAGE_SIG; flags &= ~2; } /* We do not distinguish between encrypting communications and encrypting storage. */ if (flags & (0x04 | 0x08)) { key_usage |= PUBKEY_USAGE_ENC; flags &= ~(0x04 | 0x08); } if (flags & 0x20) { key_usage |= PUBKEY_USAGE_AUTH; flags &= ~0x20; } if (flags) key_usage |= PUBKEY_USAGE_UNKNOWN; if (!key_usage) key_usage |= PUBKEY_USAGE_NONE; } else if (p) /* Key flags of length zero. */ key_usage |= PUBKEY_USAGE_NONE; /* We set PUBKEY_USAGE_UNKNOWN to indicate that this key has a capability that we do not handle. This serves to distinguish between a zero key usage which we handle as the default capabilities for that algorithm, and a usage that we do not handle. Likewise we use PUBKEY_USAGE_NONE to indicate that key_flags have been given but they do not specify any usage. */ return key_usage; } /* Apply information from SIGNODE (which is the valid self-signature * associated with that UID) to the UIDNODE: * - wether the UID has been revoked * - assumed creation date of the UID * - temporary store the keyflags here * - temporary store the key expiration time here * - mark whether the primary user ID flag hat been set. * - store the preferences */ static void fixup_uidnode (KBNODE uidnode, KBNODE signode, u32 keycreated) { PKT_user_id *uid = uidnode->pkt->pkt.user_id; PKT_signature *sig = signode->pkt->pkt.signature; const byte *p, *sym, *aead, *hash, *zip; size_t n, nsym, naead, nhash, nzip; sig->flags.chosen_selfsig = 1;/* We chose this one. */ uid->created = 0; /* Not created == invalid. */ if (IS_UID_REV (sig)) { uid->flags.revoked = 1; return; /* Has been revoked. */ } else uid->flags.revoked = 0; uid->expiredate = sig->expiredate; if (sig->flags.expired) { uid->flags.expired = 1; return; /* Has expired. */ } else uid->flags.expired = 0; uid->created = sig->timestamp; /* This one is okay. */ uid->selfsigversion = sig->version; /* If we got this far, it's not expired :) */ uid->flags.expired = 0; /* Store the key flags in the helper variable for later processing. */ uid->help_key_usage = parse_key_usage (sig); /* Ditto for the key expiration. */ p = parse_sig_subpkt (sig, 1, SIGSUBPKT_KEY_EXPIRE, NULL); if (p && buf32_to_u32 (p)) uid->help_key_expire = keycreated + buf32_to_u32 (p); else uid->help_key_expire = 0; /* Set the primary user ID flag - we will later wipe out some * of them to only have one in our keyblock. */ uid->flags.primary = 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_PRIMARY_UID, NULL); if (p && *p) uid->flags.primary = 2; /* We could also query this from the unhashed area if it is not in * the hased area and then later try to decide which is the better * there should be no security problem with this. * For now we only look at the hashed one. */ /* Now build the preferences list. These must come from the hashed section so nobody can modify the ciphers a key is willing to accept. */ p = parse_sig_subpkt (sig, 1, SIGSUBPKT_PREF_SYM, &n); sym = p; nsym = p ? n : 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_PREF_AEAD, &n); aead = p; naead = p ? n : 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_PREF_HASH, &n); hash = p; nhash = p ? n : 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_PREF_COMPR, &n); zip = p; nzip = p ? n : 0; if (uid->prefs) xfree (uid->prefs); n = nsym + naead + nhash + nzip; if (!n) uid->prefs = NULL; else { uid->prefs = xmalloc (sizeof (*uid->prefs) * (n + 1)); n = 0; for (; nsym; nsym--, n++) { uid->prefs[n].type = PREFTYPE_SYM; uid->prefs[n].value = *sym++; } for (; naead; naead--, n++) { uid->prefs[n].type = PREFTYPE_AEAD; uid->prefs[n].value = *aead++; } for (; nhash; nhash--, n++) { uid->prefs[n].type = PREFTYPE_HASH; uid->prefs[n].value = *hash++; } for (; nzip; nzip--, n++) { uid->prefs[n].type = PREFTYPE_ZIP; uid->prefs[n].value = *zip++; } uid->prefs[n].type = PREFTYPE_NONE; /* End of list marker */ uid->prefs[n].value = 0; } /* See whether we have the MDC feature. */ uid->flags.mdc = 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_FEATURES, &n); if (p && n && (p[0] & 0x01)) uid->flags.mdc = 1; /* See whether we have the AEAD feature. */ uid->flags.aead = 0; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_FEATURES, &n); if (p && n && (p[0] & 0x02)) uid->flags.aead = 1; /* And the keyserver modify flag. */ uid->flags.ks_modify = 1; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_KS_FLAGS, &n); if (p && n && (p[0] & 0x80)) uid->flags.ks_modify = 0; } static void sig_to_revoke_info (PKT_signature * sig, struct revoke_info *rinfo) { rinfo->date = sig->timestamp; rinfo->algo = sig->pubkey_algo; rinfo->keyid[0] = sig->keyid[0]; rinfo->keyid[1] = sig->keyid[1]; } /* Given a keyblock, parse the key block and extract various pieces of * information and save them with the primary key packet and the user * id packets. For instance, some information is stored in signature * packets. We find the latest such valid packet (since the user can * change that information) and copy its contents into the * PKT_public_key. * * Note that R_REVOKED may be set to 0, 1 or 2. * * This function fills in the following fields in the primary key's * keyblock: * * main_keyid (computed) * revkey / numrevkeys (derived from self signed key data) * flags.valid (whether we have at least 1 self-sig) * flags.maybe_revoked (whether a designed revoked the key, but * we are missing the key to check the sig) * selfsigversion (highest version of any valid self-sig) * pubkey_usage (derived from most recent self-sig or most * recent user id) * has_expired (various sources) * expiredate (various sources) * * See the documentation for fixup_uidnode for how the user id packets * are modified. In addition to that the primary user id's is_primary * field is set to 1 and the other user id's is_primary are set to 0. */ static void merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked, struct revoke_info *rinfo) { PKT_public_key *pk = NULL; KBNODE k; u32 kid[2]; u32 sigdate, uiddate, uiddate2; KBNODE signode, uidnode, uidnode2; u32 curtime = make_timestamp (); unsigned int key_usage = 0; u32 keytimestamp = 0; /* Creation time of the key. */ u32 key_expire = 0; int key_expire_seen = 0; byte sigversion = 0; *r_revoked = 0; memset (rinfo, 0, sizeof (*rinfo)); /* Section 11.1 of RFC 4880 determines the order of packets within a * message. There are three sections, which must occur in the * following order: the public key, the user ids and user attributes * and the subkeys. Within each section, each primary packet (e.g., * a user id packet) is followed by one or more signature packets, * which modify that packet. */ /* According to Section 11.1 of RFC 4880, the public key must be the first packet. Note that parse_keyblock_image ensures that the first packet is the public key. */ if (keyblock->pkt->pkttype != PKT_PUBLIC_KEY) BUG (); pk = keyblock->pkt->pkt.public_key; keytimestamp = pk->timestamp; keyid_from_pk (pk, kid); pk->main_keyid[0] = kid[0]; pk->main_keyid[1] = kid[1]; if (pk->version < 4) { /* Before v4 the key packet itself contains the expiration date * and there was no way to change it, so we start with the one * from the key packet. We do not support v3 keys anymore but * we keep the code in case a future key versions introduces a * hadr expire time again. */ key_expire = pk->max_expiredate; key_expire_seen = 1; } /* First pass: * * - Find the latest direct key self-signature. We assume that the * newest one overrides all others. * * - Determine whether the key has been revoked. * * - Gather all revocation keys (unlike other data, we don't just * take them from the latest self-signed packet). * * - Determine max (sig[...]->version). */ /* Reset this in case this key was already merged. */ xfree (pk->revkey); pk->revkey = NULL; pk->numrevkeys = 0; signode = NULL; sigdate = 0; /* Helper variable to find the latest signature. */ /* According to Section 11.1 of RFC 4880, the public key comes first * and is immediately followed by any signature packets that modify * it. */ for (k = keyblock; k && k->pkt->pkttype != PKT_USER_ID && k->pkt->pkttype != PKT_ATTRIBUTE && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_SIGNATURE) { PKT_signature *sig = k->pkt->pkt.signature; if (sig->keyid[0] == kid[0] && sig->keyid[1] == kid[1]) { /* Self sig. */ if (check_key_signature (ctrl, keyblock, k, NULL)) ; /* Signature did not verify. */ else if (IS_KEY_REV (sig)) { /* Key has been revoked - there is no way to * override such a revocation, so we theoretically * can stop now. We should not cope with expiration * times for revocations here because we have to * assume that an attacker can generate all kinds of * signatures. However due to the fact that the key * has been revoked it does not harm either and by * continuing we gather some more info on that * key. */ *r_revoked = 1; sig_to_revoke_info (sig, rinfo); } else if (IS_KEY_SIG (sig)) { /* Add the indicated revocations keys from all * signatures not just the latest. We do this * because you need multiple 1F sigs to properly * handle revocation keys (PGP does it this way, and * a revocation key could be sensitive and hence in * a different signature). */ if (sig->revkey) { int i; pk->revkey = xrealloc (pk->revkey, sizeof (struct revocation_key) * (pk->numrevkeys + sig->numrevkeys)); for (i = 0; i < sig->numrevkeys; i++, pk->numrevkeys++) { pk->revkey[pk->numrevkeys].class = sig->revkey[i].class; pk->revkey[pk->numrevkeys].algid = sig->revkey[i].algid; pk->revkey[pk->numrevkeys].fprlen = sig->revkey[i].fprlen; memcpy (pk->revkey[pk->numrevkeys].fpr, sig->revkey[i].fpr, sig->revkey[i].fprlen); memset (pk->revkey[pk->numrevkeys].fpr + sig->revkey[i].fprlen, 0, sizeof (sig->revkey[i].fpr) - sig->revkey[i].fprlen); } } if (sig->timestamp >= sigdate) { /* This is the latest signature so far. */ if (sig->flags.expired) ; /* Signature has expired - ignore it. */ else { sigdate = sig->timestamp; signode = k; if (sig->version > sigversion) sigversion = sig->version; } } } } } } /* Remove dupes from the revocation keys. */ if (pk->revkey) { int i, j, x, changed = 0; for (i = 0; i < pk->numrevkeys; i++) { for (j = i + 1; j < pk->numrevkeys; j++) { if (memcmp (&pk->revkey[i], &pk->revkey[j], sizeof (struct revocation_key)) == 0) { /* remove j */ for (x = j; x < pk->numrevkeys - 1; x++) pk->revkey[x] = pk->revkey[x + 1]; pk->numrevkeys--; j--; changed = 1; } } } if (changed) pk->revkey = xrealloc (pk->revkey, pk->numrevkeys * sizeof (struct revocation_key)); } /* SIGNODE is the direct key signature packet (sigclass 0x1f) with * the latest creation time. Extract some information from it. */ if (signode) { /* Some information from a direct key signature take precedence * over the same information given in UID sigs. */ PKT_signature *sig = signode->pkt->pkt.signature; const byte *p; key_usage = parse_key_usage (sig); p = parse_sig_subpkt (sig, 1, SIGSUBPKT_KEY_EXPIRE, NULL); if (p && buf32_to_u32 (p)) { key_expire = keytimestamp + buf32_to_u32 (p); key_expire_seen = 1; } /* Mark that key as valid: One direct key signature should * render a key as valid. */ pk->flags.valid = 1; } /* Pass 1.5: Look for key revocation signatures that were not made * by the key (i.e. did a revocation key issue a revocation for * us?). Only bother to do this if there is a revocation key in the * first place and we're not revoked already. */ if (!*r_revoked && pk->revkey) for (k = keyblock; k && k->pkt->pkttype != PKT_USER_ID; k = k->next) { if (k->pkt->pkttype == PKT_SIGNATURE) { PKT_signature *sig = k->pkt->pkt.signature; if (IS_KEY_REV (sig) && (sig->keyid[0] != kid[0] || sig->keyid[1] != kid[1])) { int rc = check_revocation_keys (ctrl, pk, sig); if (rc == 0) { *r_revoked = 2; sig_to_revoke_info (sig, rinfo); /* Don't continue checking since we can't be any * more revoked than this. */ break; } else if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY) pk->flags.maybe_revoked = 1; /* A failure here means the sig did not verify, was * not issued by a revocation key, or a revocation * key loop was broken. If a revocation key isn't * findable, however, the key might be revoked and * we don't know it. */ /* Fixme: In the future handle subkey and cert * revocations? PGP doesn't, but it's in 2440. */ } } } /* Second pass: Look at the self-signature of all user IDs. */ /* According to RFC 4880 section 11.1, user id and attribute packets * are in the second section, after the public key packet and before * the subkey packets. */ signode = uidnode = NULL; sigdate = 0; /* Helper variable to find the latest signature in one UID. */ for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID || k->pkt->pkttype == PKT_ATTRIBUTE) { /* New user id packet. */ /* Apply the data from the most recent self-signed packet to * the preceding user id packet. */ if (uidnode && signode) { fixup_uidnode (uidnode, signode, keytimestamp); pk->flags.valid = 1; } /* Clear SIGNODE. The only relevant self-signed data for * UIDNODE follows it. */ if (k->pkt->pkttype == PKT_USER_ID) uidnode = k; else uidnode = NULL; signode = NULL; sigdate = 0; } else if (k->pkt->pkttype == PKT_SIGNATURE && uidnode) { PKT_signature *sig = k->pkt->pkt.signature; if (sig->keyid[0] == kid[0] && sig->keyid[1] == kid[1]) { if (check_key_signature (ctrl, keyblock, k, NULL)) ; /* signature did not verify */ else if ((IS_UID_SIG (sig) || IS_UID_REV (sig)) && sig->timestamp >= sigdate) { /* Note: we allow invalidation of cert revocations * by a newer signature. An attacker can't use this * because a key should be revoked with a key revocation. * The reason why we have to allow for that is that at * one time an email address may become invalid but later * the same email address may become valid again (hired, * fired, hired again). */ sigdate = sig->timestamp; signode = k; signode->pkt->pkt.signature->flags.chosen_selfsig = 0; if (sig->version > sigversion) sigversion = sig->version; } } } } if (uidnode && signode) { fixup_uidnode (uidnode, signode, keytimestamp); pk->flags.valid = 1; } /* If the key isn't valid yet, and we have * --allow-non-selfsigned-uid set, then force it valid. */ if (!pk->flags.valid && opt.allow_non_selfsigned_uid) { if (opt.verbose) log_info (_("Invalid key %s made valid by" " --allow-non-selfsigned-uid\n"), keystr_from_pk (pk)); pk->flags.valid = 1; } /* The key STILL isn't valid, so try and find an ultimately * trusted signature. */ if (!pk->flags.valid) { uidnode = NULL; for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID) uidnode = k; else if (k->pkt->pkttype == PKT_SIGNATURE && uidnode) { PKT_signature *sig = k->pkt->pkt.signature; if (sig->keyid[0] != kid[0] || sig->keyid[1] != kid[1]) { PKT_public_key *ultimate_pk; ultimate_pk = xmalloc_clear (sizeof (*ultimate_pk)); /* We don't want to use the full get_pubkey to avoid * infinite recursion in certain cases. There is no * reason to check that an ultimately trusted key is * still valid - if it has been revoked the user * should also remove the ultimate trust flag. */ if (get_pubkey_fast (ctrl, ultimate_pk, sig->keyid) == 0 && check_key_signature2 (ctrl, keyblock, k, ultimate_pk, NULL, NULL, NULL, NULL) == 0 && get_ownertrust (ctrl, ultimate_pk) == TRUST_ULTIMATE) { free_public_key (ultimate_pk); pk->flags.valid = 1; break; } free_public_key (ultimate_pk); } } } } /* Record the highest selfsig version so we know if this is a v3 key * through and through, or a v3 key with a v4 selfsig somewhere. * This is useful in a few places to know if the key must be treated * as PGP2-style or OpenPGP-style. Note that a selfsig revocation * with a higher version number will also raise this value. This is * okay since such a revocation must be issued by the user (i.e. it * cannot be issued by someone else to modify the key behavior.) */ pk->selfsigversion = sigversion; /* Now that we had a look at all user IDs we can now get some * information from those user IDs. */ if (!key_usage) { /* Find the latest user ID with key flags set. */ uiddate = 0; /* Helper to find the latest user ID. */ for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID) { PKT_user_id *uid = k->pkt->pkt.user_id; if (uid->help_key_usage && (uid->created > uiddate || (!uid->created && !uiddate))) { key_usage = uid->help_key_usage; uiddate = uid->created; } } } } if (!key_usage) { /* No key flags at all: get it from the algo. */ key_usage = openpgp_pk_algo_usage (pk->pubkey_algo); } else { /* Check that the usage matches the usage as given by the algo. */ int x = openpgp_pk_algo_usage (pk->pubkey_algo); if (x) /* Mask it down to the actual allowed usage. */ key_usage &= x; } /* Whatever happens, it's a primary key, so it can certify. */ pk->pubkey_usage = key_usage | PUBKEY_USAGE_CERT; if (!key_expire_seen) { /* Find the latest valid user ID with a key expiration set. * This may be a different one than from usage computation above * because some user IDs may have no expiration date set. */ uiddate = 0; for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID) { PKT_user_id *uid = k->pkt->pkt.user_id; if (uid->help_key_expire && (uid->created > uiddate || (!uid->created && !uiddate))) { key_expire = uid->help_key_expire; uiddate = uid->created; } } } } /* Currently only the not anymore supported v3 keys have a maximum * expiration date, but future key versions may get this feature again. */ if (key_expire == 0 || (pk->max_expiredate && key_expire > pk->max_expiredate)) key_expire = pk->max_expiredate; pk->has_expired = key_expire >= curtime ? 0 : key_expire; pk->expiredate = key_expire; /* Fixme: we should see how to get rid of the expiretime fields but * this needs changes at other places too. */ /* And now find the real primary user ID and delete all others. */ uiddate = uiddate2 = 0; uidnode = uidnode2 = NULL; for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID && !k->pkt->pkt.user_id->attrib_data) { PKT_user_id *uid = k->pkt->pkt.user_id; if (uid->flags.primary) { if (uid->created > uiddate) { uiddate = uid->created; uidnode = k; } else if (uid->created == uiddate && uidnode) { /* The dates are equal, so we need to do a different * (and arbitrary) comparison. This should rarely, * if ever, happen. It's good to try and guarantee * that two different GnuPG users with two different * keyrings at least pick the same primary. */ if (cmp_user_ids (uid, uidnode->pkt->pkt.user_id) > 0) uidnode = k; } } else { if (uid->created > uiddate2) { uiddate2 = uid->created; uidnode2 = k; } else if (uid->created == uiddate2 && uidnode2) { if (cmp_user_ids (uid, uidnode2->pkt->pkt.user_id) > 0) uidnode2 = k; } } } } if (uidnode) { for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID && !k->pkt->pkt.user_id->attrib_data) { PKT_user_id *uid = k->pkt->pkt.user_id; if (k != uidnode) uid->flags.primary = 0; } } } else if (uidnode2) { /* None is flagged primary - use the latest user ID we have, * and disambiguate with the arbitrary packet comparison. */ uidnode2->pkt->pkt.user_id->flags.primary = 1; } else { /* None of our uids were self-signed, so pick the one that * sorts first to be the primary. This is the best we can do * here since there are no self sigs to date the uids. */ uidnode = NULL; for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID && !k->pkt->pkt.user_id->attrib_data) { if (!uidnode) { uidnode = k; uidnode->pkt->pkt.user_id->flags.primary = 1; continue; } else { if (cmp_user_ids (k->pkt->pkt.user_id, uidnode->pkt->pkt.user_id) > 0) { uidnode->pkt->pkt.user_id->flags.primary = 0; uidnode = k; uidnode->pkt->pkt.user_id->flags.primary = 1; } else { /* just to be safe: */ k->pkt->pkt.user_id->flags.primary = 0; } } } } } } /* Convert a buffer to a signature. Useful for 0x19 embedded sigs. * Caller must free the signature when they are done. */ static PKT_signature * buf_to_sig (const byte * buf, size_t len) { PKT_signature *sig = xmalloc_clear (sizeof (PKT_signature)); IOBUF iobuf = iobuf_temp_with_content (buf, len); int save_mode = set_packet_list_mode (0); if (parse_signature (iobuf, PKT_SIGNATURE, len, sig) != 0) { free_seckey_enc (sig); sig = NULL; } set_packet_list_mode (save_mode); iobuf_close (iobuf); return sig; } /* Use the self-signed data to fill in various fields in subkeys. * * KEYBLOCK is the whole keyblock. SUBNODE is the subkey to fill in. * * Sets the following fields on the subkey: * * main_keyid * flags.valid if the subkey has a valid self-sig binding * flags.revoked * flags.backsig * pubkey_usage * has_expired * expired_date * * On this subkey's most revent valid self-signed packet, the * following field is set: * * flags.chosen_selfsig */ static void merge_selfsigs_subkey (ctrl_t ctrl, kbnode_t keyblock, kbnode_t subnode) { PKT_public_key *mainpk = NULL, *subpk = NULL; PKT_signature *sig; KBNODE k; u32 mainkid[2]; u32 sigdate = 0; KBNODE signode; u32 curtime = make_timestamp (); unsigned int key_usage = 0; u32 keytimestamp = 0; u32 key_expire = 0; const byte *p; if (subnode->pkt->pkttype != PKT_PUBLIC_SUBKEY) BUG (); mainpk = keyblock->pkt->pkt.public_key; if (mainpk->version < 4) return;/* (actually this should never happen) */ keyid_from_pk (mainpk, mainkid); subpk = subnode->pkt->pkt.public_key; keytimestamp = subpk->timestamp; subpk->flags.valid = 0; subpk->flags.exact = 0; subpk->main_keyid[0] = mainpk->main_keyid[0]; subpk->main_keyid[1] = mainpk->main_keyid[1]; /* Find the latest key binding self-signature. */ signode = NULL; sigdate = 0; /* Helper to find the latest signature. */ for (k = subnode->next; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_SIGNATURE) { sig = k->pkt->pkt.signature; if (sig->keyid[0] == mainkid[0] && sig->keyid[1] == mainkid[1]) { if (check_key_signature (ctrl, keyblock, k, NULL)) ; /* Signature did not verify. */ else if (IS_SUBKEY_REV (sig)) { /* Note that this means that the date on a * revocation sig does not matter - even if the * binding sig is dated after the revocation sig, * the subkey is still marked as revoked. This * seems ok, as it is just as easy to make new * subkeys rather than re-sign old ones as the * problem is in the distribution. Plus, PGP (7) * does this the same way. */ subpk->flags.revoked = 1; sig_to_revoke_info (sig, &subpk->revoked); /* Although we could stop now, we continue to * figure out other information like the old expiration * time. */ } else if (IS_SUBKEY_SIG (sig) && sig->timestamp >= sigdate) { if (sig->flags.expired) ; /* Signature has expired - ignore it. */ else { sigdate = sig->timestamp; signode = k; signode->pkt->pkt.signature->flags.chosen_selfsig = 0; } } } } } /* No valid key binding. */ if (!signode) return; sig = signode->pkt->pkt.signature; sig->flags.chosen_selfsig = 1; /* So we know which selfsig we chose later. */ key_usage = parse_key_usage (sig); if (!key_usage) { /* No key flags at all: get it from the algo. */ key_usage = openpgp_pk_algo_usage (subpk->pubkey_algo); } else { /* Check that the usage matches the usage as given by the algo. */ int x = openpgp_pk_algo_usage (subpk->pubkey_algo); if (x) /* Mask it down to the actual allowed usage. */ key_usage &= x; } subpk->pubkey_usage = key_usage; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_KEY_EXPIRE, NULL); if (p && buf32_to_u32 (p)) key_expire = keytimestamp + buf32_to_u32 (p); else key_expire = 0; subpk->has_expired = key_expire >= curtime ? 0 : key_expire; subpk->expiredate = key_expire; /* Algo doesn't exist. */ if (openpgp_pk_test_algo (subpk->pubkey_algo)) return; subpk->flags.valid = 1; /* Find the most recent 0x19 embedded signature on our self-sig. */ if (!subpk->flags.backsig) { int seq = 0; size_t n; PKT_signature *backsig = NULL; sigdate = 0; /* We do this while() since there may be other embedded * signatures in the future. We only want 0x19 here. */ while ((p = enum_sig_subpkt (sig, 1, SIGSUBPKT_SIGNATURE, &n, &seq, NULL))) if (n > 3 && ((p[0] == 3 && p[2] == 0x19) || (p[0] == 4 && p[1] == 0x19))) { PKT_signature *tempsig = buf_to_sig (p, n); if (tempsig) { if (tempsig->timestamp > sigdate) { if (backsig) free_seckey_enc (backsig); backsig = tempsig; sigdate = backsig->timestamp; } else free_seckey_enc (tempsig); } } seq = 0; /* It is safe to have this in the unhashed area since the 0x19 * is located on the selfsig for convenience, not security. */ while ((p = enum_sig_subpkt (sig, 0, SIGSUBPKT_SIGNATURE, &n, &seq, NULL))) if (n > 3 && ((p[0] == 3 && p[2] == 0x19) || (p[0] == 4 && p[1] == 0x19))) { PKT_signature *tempsig = buf_to_sig (p, n); if (tempsig) { if (tempsig->timestamp > sigdate) { if (backsig) free_seckey_enc (backsig); backsig = tempsig; sigdate = backsig->timestamp; } else free_seckey_enc (tempsig); } } if (backsig) { /* At this point, backsig contains the most recent 0x19 sig. * Let's see if it is good. */ /* 2==valid, 1==invalid, 0==didn't check */ if (check_backsig (mainpk, subpk, backsig) == 0) subpk->flags.backsig = 2; else subpk->flags.backsig = 1; free_seckey_enc (backsig); } } } /* Merge information from the self-signatures with the public key, * subkeys and user ids to make using them more easy. * * See documentation for merge_selfsigs_main, merge_selfsigs_subkey * and fixup_uidnode for exactly which fields are updated. */ static void merge_selfsigs (ctrl_t ctrl, kbnode_t keyblock) { KBNODE k; int revoked; struct revoke_info rinfo; PKT_public_key *main_pk; prefitem_t *prefs; unsigned int mdc_feature; unsigned int aead_feature; if (keyblock->pkt->pkttype != PKT_PUBLIC_KEY) { if (keyblock->pkt->pkttype == PKT_SECRET_KEY) { log_error ("expected public key but found secret key " "- must stop\n"); /* We better exit here because a public key is expected at * other places too. FIXME: Figure this out earlier and * don't get to here at all */ g10_exit (1); } BUG (); } merge_selfsigs_main (ctrl, keyblock, &revoked, &rinfo); /* Now merge in the data from each of the subkeys. */ for (k = keyblock; k; k = k->next) { if (k->pkt->pkttype == PKT_PUBLIC_SUBKEY) { merge_selfsigs_subkey (ctrl, keyblock, k); } } main_pk = keyblock->pkt->pkt.public_key; if (revoked || main_pk->has_expired || !main_pk->flags.valid) { /* If the primary key is revoked, expired, or invalid we * better set the appropriate flags on that key and all * subkeys. */ for (k = keyblock; k; k = k->next) { if (k->pkt->pkttype == PKT_PUBLIC_KEY || k->pkt->pkttype == PKT_PUBLIC_SUBKEY) { PKT_public_key *pk = k->pkt->pkt.public_key; if (!main_pk->flags.valid) pk->flags.valid = 0; if (revoked && !pk->flags.revoked) { pk->flags.revoked = revoked; memcpy (&pk->revoked, &rinfo, sizeof (rinfo)); } if (main_pk->has_expired) { pk->has_expired = main_pk->has_expired; if (!pk->expiredate || pk->expiredate > main_pk->expiredate) pk->expiredate = main_pk->expiredate; } } } return; } /* Set the preference list of all keys to those of the primary real * user ID. Note: we use these preferences when we don't know by * which user ID the key has been selected. * fixme: we should keep atoms of commonly used preferences or * use reference counting to optimize the preference lists storage. * FIXME: it might be better to use the intersection of * all preferences. * Do a similar thing for the MDC feature flag. */ prefs = NULL; mdc_feature = aead_feature = 0; for (k = keyblock; k && k->pkt->pkttype != PKT_PUBLIC_SUBKEY; k = k->next) { if (k->pkt->pkttype == PKT_USER_ID && !k->pkt->pkt.user_id->attrib_data && k->pkt->pkt.user_id->flags.primary) { prefs = k->pkt->pkt.user_id->prefs; mdc_feature = k->pkt->pkt.user_id->flags.mdc; aead_feature = k->pkt->pkt.user_id->flags.aead; break; } } for (k = keyblock; k; k = k->next) { if (k->pkt->pkttype == PKT_PUBLIC_KEY || k->pkt->pkttype == PKT_PUBLIC_SUBKEY) { PKT_public_key *pk = k->pkt->pkt.public_key; if (pk->prefs) xfree (pk->prefs); pk->prefs = copy_prefs (prefs); pk->flags.mdc = mdc_feature; pk->flags.aead = aead_feature; } } } /* See whether the key satisfies any additional requirements specified * in CTX. If so, return the node of an appropriate key or subkey. * Otherwise, return NULL if there was no appropriate key. * * Note that we do not return a reference, i.e. the result must not be * freed using 'release_kbnode'. * * In case the primary key is not required, select a suitable subkey. * We need the primary key if PUBKEY_USAGE_CERT is set in REQ_USAGE or * we are in PGP7 mode and PUBKEY_USAGE_SIG is set in * REQ_USAGE. * * If any of PUBKEY_USAGE_SIG, PUBKEY_USAGE_ENC and PUBKEY_USAGE_CERT * are set in REQ_USAGE, we filter by the key's function. Concretely, * if PUBKEY_USAGE_SIG and PUBKEY_USAGE_CERT are set, then we only * return a key if it is (at least) either a signing or a * certification key. * * If REQ_USAGE is set, then we reject any keys that are not good * (i.e., valid, not revoked, not expired, etc.). This allows the * getkey functions to be used for plain key listings. * * Sets the matched key's user id field (pk->user_id) to the user id * that matched the low-level search criteria or NULL. * * If R_FLAGS is not NULL set certain flags for more detailed error * reporting. Used flags are: * * - LOOKUP_ALL_SUBKEYS_EXPIRED :: All Subkeys are expired or have * been revoked. * - LOOKUP_NOT_SELECTED :: No suitable key found * * This function needs to handle several different cases: * * 1. No requested usage and no primary key requested * Examples for this case are that we have a keyID to be used * for decryption or verification. * 2. No usage but primary key requested * This is the case for all functions which work on an * entire keyblock, e.g. for editing or listing * 3. Usage and primary key requested * FIXME * 4. Usage but no primary key requested * FIXME * */ static kbnode_t finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact, int want_secret, unsigned int *r_flags) { kbnode_t k; /* If WANT_EXACT is set, the key or subkey that actually matched the low-level search criteria. */ kbnode_t foundk = NULL; /* The user id (if any) that matched the low-level search criteria. */ PKT_user_id *foundu = NULL; u32 latest_date; kbnode_t latest_key; PKT_public_key *pk; int req_prim; u32 curtime = make_timestamp (); if (r_flags) *r_flags = 0; #define USAGE_MASK (PUBKEY_USAGE_SIG|PUBKEY_USAGE_ENC|PUBKEY_USAGE_CERT) req_usage &= USAGE_MASK; /* Request the primary if we're certifying another key, and also if * signing data while --pgp7 is on since pgp 7 do * not understand signatures made by a signing subkey. PGP 8 does. */ req_prim = ((req_usage & PUBKEY_USAGE_CERT) || (PGP7 && (req_usage & PUBKEY_USAGE_SIG))); log_assert (keyblock->pkt->pkttype == PKT_PUBLIC_KEY); /* For an exact match mark the primary or subkey that matched the low-level search criteria. */ if (want_exact) { for (k = keyblock; k; k = k->next) { if ((k->flag & 1)) { log_assert (k->pkt->pkttype == PKT_PUBLIC_KEY || k->pkt->pkttype == PKT_PUBLIC_SUBKEY); foundk = k; pk = k->pkt->pkt.public_key; pk->flags.exact = 1; break; } } } /* Get the user id that matched that low-level search criteria. */ for (k = keyblock; k; k = k->next) { if ((k->flag & 2)) { log_assert (k->pkt->pkttype == PKT_USER_ID); foundu = k->pkt->pkt.user_id; break; } } if (DBG_LOOKUP) log_debug ("finish_lookup: checking key %08lX (%s)(req_usage=%x)\n", (ulong) keyid_from_pk (keyblock->pkt->pkt.public_key, NULL), foundk ? "one" : "all", req_usage); if (!req_usage) { latest_key = foundk ? foundk : keyblock; goto found; } latest_date = 0; latest_key = NULL; /* Set LATEST_KEY to the latest (the one with the most recent * timestamp) good (valid, not revoked, not expired, etc.) subkey. * * Don't bother if we are only looking for a primary key or we need * an exact match and the exact match is not a subkey. */ if (req_prim || (foundk && foundk->pkt->pkttype != PKT_PUBLIC_SUBKEY)) ; else { kbnode_t nextk; int n_subkeys = 0; int n_revoked_or_expired = 0; int last_secret_key_avail = 0; /* Either start a loop or check just this one subkey. */ for (k = foundk ? foundk : keyblock; k; k = nextk) { if (foundk) { /* If FOUNDK is not NULL, then only consider that exact key, i.e., don't iterate. */ nextk = NULL; } else nextk = k->next; if (k->pkt->pkttype != PKT_PUBLIC_SUBKEY) continue; pk = k->pkt->pkt.public_key; if (DBG_LOOKUP) log_debug ("\tchecking subkey %08lX\n", (ulong) keyid_from_pk (pk, NULL)); if (!pk->flags.valid) { if (DBG_LOOKUP) log_debug ("\tsubkey not valid\n"); continue; } if (!((pk->pubkey_usage & USAGE_MASK) & req_usage)) { if (DBG_LOOKUP) log_debug ("\tusage does not match: want=%x have=%x\n", req_usage, pk->pubkey_usage); continue; } n_subkeys++; if (pk->flags.revoked) { if (DBG_LOOKUP) log_debug ("\tsubkey has been revoked\n"); n_revoked_or_expired++; continue; } if (pk->has_expired) { if (DBG_LOOKUP) log_debug ("\tsubkey has expired\n"); n_revoked_or_expired++; continue; } if (pk->timestamp > curtime && !opt.ignore_valid_from) { if (DBG_LOOKUP) log_debug ("\tsubkey not yet valid\n"); continue; } if (want_secret) { int secret_key_avail = agent_probe_secret_key (NULL, pk); if (!secret_key_avail) { if (DBG_LOOKUP) log_debug ("\tno secret key\n"); continue; } if (secret_key_avail > last_secret_key_avail) { /* Use this key. */ last_secret_key_avail = secret_key_avail; latest_date = 0; } } if (DBG_LOOKUP) log_debug ("\tsubkey might be fine\n"); /* In case a key has a timestamp of 0 set, we make sure that it is used. A better change would be to compare ">=" but that might also change the selected keys and is as such a more intrusive change. */ if (pk->timestamp > latest_date || (!pk->timestamp && !latest_date)) { latest_date = pk->timestamp; latest_key = k; } } if (n_subkeys == n_revoked_or_expired && r_flags) *r_flags |= LOOKUP_ALL_SUBKEYS_EXPIRED; } /* Check if the primary key is ok (valid, not revoke, not expire, * matches requested usage) if: * * - we didn't find an appropriate subkey and we're not doing an * exact search, * * - we're doing an exact match and the exact match was the * primary key, or, * * - we're just considering the primary key. */ if ((!latest_key && !want_exact) || foundk == keyblock || req_prim) { if (DBG_LOOKUP && !foundk && !req_prim) log_debug ("\tno suitable subkeys found - trying primary\n"); pk = keyblock->pkt->pkt.public_key; if (!pk->flags.valid) { if (DBG_LOOKUP) log_debug ("\tprimary key not valid\n"); } else if (!((pk->pubkey_usage & USAGE_MASK) & req_usage)) { if (DBG_LOOKUP) log_debug ("\tprimary key usage does not match: " "want=%x have=%x\n", req_usage, pk->pubkey_usage); } else if (pk->flags.revoked) { if (DBG_LOOKUP) log_debug ("\tprimary key has been revoked\n"); } else if (pk->has_expired) { if (DBG_LOOKUP) log_debug ("\tprimary key has expired\n"); } else /* Okay. */ { if (DBG_LOOKUP) log_debug ("\tprimary key may be used\n"); latest_key = keyblock; } } if (!latest_key) { if (DBG_LOOKUP) log_debug ("\tno suitable key found - giving up\n"); if (r_flags) *r_flags |= LOOKUP_NOT_SELECTED; return NULL; /* Not found. */ } found: if (DBG_LOOKUP) log_debug ("\tusing key %08lX\n", (ulong) keyid_from_pk (latest_key->pkt->pkt.public_key, NULL)); if (latest_key) { pk = latest_key->pkt->pkt.public_key; free_user_id (pk->user_id); pk->user_id = scopy_user_id (foundu); } if (latest_key != keyblock && opt.verbose) { char *tempkeystr = xstrdup (keystr_from_pk (latest_key->pkt->pkt.public_key)); log_info (_("using subkey %s instead of primary key %s\n"), tempkeystr, keystr_from_pk (keyblock->pkt->pkt.public_key)); xfree (tempkeystr); } cache_put_keyblock (keyblock); return latest_key ? latest_key : keyblock; /* Found. */ } /* Print a KEY_CONSIDERED status line. */ static void print_status_key_considered (kbnode_t keyblock, unsigned int flags) { char hexfpr[2*MAX_FINGERPRINT_LEN + 1]; kbnode_t node; char flagbuf[20]; if (!is_status_enabled ()) return; for (node=keyblock; node; node = node->next) if (node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_SECRET_KEY) break; if (!node) { log_error ("%s: keyblock w/o primary key\n", __func__); return; } hexfingerprint (node->pkt->pkt.public_key, hexfpr, sizeof hexfpr); snprintf (flagbuf, sizeof flagbuf, " %u", flags); write_status_strings (STATUS_KEY_CONSIDERED, hexfpr, flagbuf, NULL); } /* A high-level function to lookup keys. * * This function builds on top of the low-level keydb API. It first * searches the database using the description stored in CTX->ITEMS, * then it filters the results using CTX and, finally, if WANT_SECRET * is set, it ignores any keys for which no secret key is available. * * Unlike the low-level search functions, this function also merges * all of the self-signed data into the keys, subkeys and user id * packets (see the merge_selfsigs for details). * * On success the key's keyblock is stored at *RET_KEYBLOCK, and the * specific subkey is stored at *RET_FOUND_KEY. Note that we do not * return a reference in *RET_FOUND_KEY, i.e. the result must not be * freed using 'release_kbnode', and it is only valid until * *RET_KEYBLOCK is deallocated. Therefore, if RET_FOUND_KEY is not * NULL, then RET_KEYBLOCK must not be NULL. */ static int lookup (ctrl_t ctrl, getkey_ctx_t ctx, int want_secret, kbnode_t *ret_keyblock, kbnode_t *ret_found_key) { int rc; int no_suitable_key = 0; KBNODE keyblock = NULL; KBNODE found_key = NULL; unsigned int infoflags; log_assert (ret_found_key == NULL || ret_keyblock != NULL); if (ret_keyblock) *ret_keyblock = NULL; for (;;) { rc = keydb_search (ctx->kr_handle, ctx->items, ctx->nitems, NULL); if (rc) break; /* If we are iterating over the entire database, then we need to * change from KEYDB_SEARCH_MODE_FIRST, which does an implicit * reset, to KEYDB_SEARCH_MODE_NEXT, which gets the next record. */ if (ctx->nitems && ctx->items->mode == KEYDB_SEARCH_MODE_FIRST) ctx->items->mode = KEYDB_SEARCH_MODE_NEXT; rc = keydb_get_keyblock (ctx->kr_handle, &keyblock); if (rc) { log_error ("keydb_get_keyblock failed: %s\n", gpg_strerror (rc)); goto skip; } if (want_secret) { rc = agent_probe_any_secret_key (NULL, keyblock); if (gpg_err_code(rc) == GPG_ERR_NO_SECKEY) goto skip; /* No secret key available. */ if (rc) goto found; /* Unexpected error. */ } /* Warning: node flag bits 0 and 1 should be preserved by * merge_selfsigs. */ merge_selfsigs (ctrl, keyblock); found_key = finish_lookup (keyblock, ctx->req_usage, ctx->exact, want_secret, &infoflags); print_status_key_considered (keyblock, infoflags); if (found_key) { no_suitable_key = 0; goto found; } else { no_suitable_key = 1; } skip: /* Release resources and continue search. */ release_kbnode (keyblock); keyblock = NULL; /* The keyblock cache ignores the current "file position". * Thus, if we request the next result and the cache matches * (and it will since it is what we just looked for), we'll get * the same entry back! We can avoid this infinite loop by * disabling the cache. */ keydb_disable_caching (ctx->kr_handle); } found: if (rc && gpg_err_code (rc) != GPG_ERR_NOT_FOUND) log_error ("keydb_search failed: %s\n", gpg_strerror (rc)); if (!rc) { if (ret_keyblock) { *ret_keyblock = keyblock; /* Return the keyblock. */ keyblock = NULL; } } else if (gpg_err_code (rc) == GPG_ERR_NOT_FOUND && no_suitable_key) rc = want_secret? GPG_ERR_UNUSABLE_SECKEY : GPG_ERR_UNUSABLE_PUBKEY; else if (gpg_err_code (rc) == GPG_ERR_NOT_FOUND) rc = want_secret? GPG_ERR_NO_SECKEY : GPG_ERR_NO_PUBKEY; release_kbnode (keyblock); if (ret_found_key) { if (! rc) *ret_found_key = found_key; else *ret_found_key = NULL; } return rc; } gpg_error_t get_seckey_default_or_card (ctrl_t ctrl, PKT_public_key *pk, const byte *fpr_card, size_t fpr_len) { gpg_error_t err; strlist_t namelist = NULL; const char *def_secret_key = parse_def_secret_key (ctrl); if (def_secret_key) add_to_strlist (&namelist, def_secret_key); else if (fpr_card) { int rc = get_pubkey_byfprint (ctrl, pk, NULL, fpr_card, fpr_len); /* The key on card can be not suitable for requested usage. */ if (rc == GPG_ERR_UNUSABLE_PUBKEY) fpr_card = NULL; /* Fallthrough as no card. */ else return rc; } if (!fpr_card || (def_secret_key && def_secret_key[strlen (def_secret_key)-1] == '!')) err = key_byname (ctrl, NULL, namelist, pk, 1, 0, NULL, NULL); else { /* Default key is specified and card key is also available. */ kbnode_t k, keyblock = NULL; err = key_byname (ctrl, NULL, namelist, pk, 1, 0, &keyblock, NULL); if (!err) for (k = keyblock; k; k = k->next) { PKT_public_key *pk_candidate; char fpr[MAX_FINGERPRINT_LEN]; if (k->pkt->pkttype != PKT_PUBLIC_KEY &&k->pkt->pkttype != PKT_PUBLIC_SUBKEY) continue; pk_candidate = k->pkt->pkt.public_key; if (!pk_candidate->flags.valid) continue; if (!((pk_candidate->pubkey_usage & USAGE_MASK) & pk->req_usage)) continue; fingerprint_from_pk (pk_candidate, fpr, NULL); if (!memcmp (fpr_card, fpr, fpr_len)) { release_public_key_parts (pk); copy_public_key (pk, pk_candidate); break; } } release_kbnode (keyblock); } free_strlist (namelist); return err; } /********************************************* *********** User ID printing helpers ******* *********************************************/ /* Return a string with a printable representation of the user_id. * this string must be freed by xfree. If R_NOUID is not NULL it is * set to true if a user id was not found; otherwise to false. */ static char * get_user_id_string (ctrl_t ctrl, u32 * keyid, int mode) { char *name; unsigned int namelen; char *p; log_assert (mode != 2); name = cache_get_uid_bykid (keyid, &namelen); if (!name) { /* Get it so that the cache will be filled. */ if (!get_pubkey (ctrl, NULL, keyid)) name = cache_get_uid_bykid (keyid, &namelen); } if (name) { if (mode) p = xasprintf ("%08lX%08lX %.*s", (ulong) keyid[0], (ulong) keyid[1], namelen, name); else p = xasprintf ("%s %.*s", keystr (keyid), namelen, name); xfree (name); } else { if (mode) p = xasprintf ("%08lX%08lX [?]", (ulong) keyid[0], (ulong) keyid[1]); else p = xasprintf ("%s [?]", keystr (keyid)); } return p; } char * get_user_id_string_native (ctrl_t ctrl, u32 * keyid) { char *p = get_user_id_string (ctrl, keyid, 0); char *p2 = utf8_to_native (p, strlen (p), 0); xfree (p); return p2; } char * get_long_user_id_string (ctrl_t ctrl, u32 * keyid) { return get_user_id_string (ctrl, keyid, 1); } /* Please try to use get_user_byfpr instead of this one. */ char * get_user_id (ctrl_t ctrl, u32 *keyid, size_t *rn, int *r_nouid) { char *name; unsigned int namelen; if (r_nouid) *r_nouid = 0; name = cache_get_uid_bykid (keyid, &namelen); if (!name) { /* Get it so that the cache will be filled. */ if (!get_pubkey (ctrl, NULL, keyid)) name = cache_get_uid_bykid (keyid, &namelen); } if (!name) { name = xstrdup (user_id_not_found_utf8 ()); namelen = strlen (name); if (r_nouid) *r_nouid = 1; } if (rn && name) *rn = namelen; return name; } /* Please try to use get_user_id_byfpr_native instead of this one. */ char * get_user_id_native (ctrl_t ctrl, u32 *keyid) { size_t rn; char *p = get_user_id (ctrl, keyid, &rn, NULL); char *p2 = utf8_to_native (p, rn, 0); xfree (p); return p2; } /* Return the user id for a key designated by its fingerprint, FPR, which must be MAX_FINGERPRINT_LEN bytes in size. Note: the returned string, which must be freed using xfree, may not be NUL terminated. To determine the length of the string, you must use *RN. */ static char * get_user_id_byfpr (ctrl_t ctrl, const byte *fpr, size_t fprlen, size_t *rn) { char *name; name = cache_get_uid_byfpr (fpr, fprlen, rn); if (!name) { /* Get it so that the cache will be filled. */ if (!get_pubkey_byfprint (ctrl, NULL, NULL, fpr, fprlen)) name = cache_get_uid_byfpr (fpr, fprlen, rn); } if (!name) { name = xstrdup (user_id_not_found_utf8 ()); *rn = strlen (name); } return name; } /* Like get_user_id_byfpr, but convert the string to the native encoding. The returned string needs to be freed. Unlike get_user_id_byfpr, the returned string is NUL terminated. */ char * get_user_id_byfpr_native (ctrl_t ctrl, const byte *fpr, size_t fprlen) { size_t rn; char *p = get_user_id_byfpr (ctrl, fpr, fprlen, &rn); char *p2 = utf8_to_native (p, rn, 0); xfree (p); return p2; } /* Return the database handle used by this context. The context still owns the handle. */ KEYDB_HANDLE get_ctx_handle (GETKEY_CTX ctx) { return ctx->kr_handle; } static void free_akl (struct akl *akl) { if (! akl) return; if (akl->spec) free_keyserver_spec (akl->spec); xfree (akl); } void release_akl (void) { while (opt.auto_key_locate) { struct akl *akl2 = opt.auto_key_locate; opt.auto_key_locate = opt.auto_key_locate->next; free_akl (akl2); } } /* Returns true if the AKL is empty or has only the local method * active. */ int akl_empty_or_only_local (void) { struct akl *akl; int any = 0; for (akl = opt.auto_key_locate; akl; akl = akl->next) if (akl->type != AKL_NODEFAULT && akl->type != AKL_LOCAL) { any = 1; break; } return !any; } /* Returns false on error. */ int parse_auto_key_locate (const char *options_arg) { char *tok; char *options, *options_buf; options = options_buf = xstrdup (options_arg); while ((tok = optsep (&options))) { struct akl *akl, *check, *last = NULL; int dupe = 0; if (tok[0] == '\0') continue; akl = xmalloc_clear (sizeof (*akl)); if (ascii_strcasecmp (tok, "clear") == 0) { xfree (akl); free_akl (opt.auto_key_locate); opt.auto_key_locate = NULL; continue; } else if (ascii_strcasecmp (tok, "nodefault") == 0) akl->type = AKL_NODEFAULT; else if (ascii_strcasecmp (tok, "local") == 0) akl->type = AKL_LOCAL; else if (ascii_strcasecmp (tok, "ldap") == 0) akl->type = AKL_LDAP; else if (ascii_strcasecmp (tok, "keyserver") == 0) akl->type = AKL_KEYSERVER; else if (ascii_strcasecmp (tok, "cert") == 0) akl->type = AKL_CERT; else if (ascii_strcasecmp (tok, "pka") == 0) akl->type = AKL_PKA; else if (ascii_strcasecmp (tok, "dane") == 0) akl->type = AKL_DANE; else if (ascii_strcasecmp (tok, "wkd") == 0) akl->type = AKL_WKD; else if ((akl->spec = parse_keyserver_uri (tok, 1))) akl->type = AKL_SPEC; else { free_akl (akl); xfree (options_buf); return 0; } /* We must maintain the order the user gave us */ for (check = opt.auto_key_locate; check; last = check, check = check->next) { /* Check for duplicates */ if (check->type == akl->type && (akl->type != AKL_SPEC || (akl->type == AKL_SPEC && strcmp (check->spec->uri, akl->spec->uri) == 0))) { dupe = 1; free_akl (akl); break; } } if (!dupe) { if (last) last->next = akl; else opt.auto_key_locate = akl; } } xfree (options_buf); return 1; } /* The list of key origins. */ static struct { const char *name; int origin; } key_origin_list[] = { { "self", KEYORG_SELF }, { "file", KEYORG_FILE }, { "url", KEYORG_URL }, { "wkd", KEYORG_WKD }, { "dane", KEYORG_DANE }, { "ks-pref", KEYORG_KS_PREF }, { "ks", KEYORG_KS }, { "unknown", KEYORG_UNKNOWN } }; /* Parse the argument for --key-origin. Return false on error. */ int parse_key_origin (char *string) { int i; char *comma; comma = strchr (string, ','); if (comma) *comma = 0; if (!ascii_strcasecmp (string, "help")) { log_info (_("valid values for option '%s':\n"), "--key-origin"); for (i=0; i < DIM (key_origin_list); i++) log_info (" %s\n", key_origin_list[i].name); g10_exit (1); } for (i=0; i < DIM (key_origin_list); i++) if (!ascii_strcasecmp (string, key_origin_list[i].name)) { opt.key_origin = key_origin_list[i].origin; xfree (opt.key_origin_url); opt.key_origin_url = NULL; if (comma && comma[1]) { opt.key_origin_url = xstrdup (comma+1); trim_spaces (opt.key_origin_url); } return 1; } if (comma) *comma = ','; return 0; } /* Return a string or "?" for the key ORIGIN. */ const char * key_origin_string (int origin) { int i; for (i=0; i < DIM (key_origin_list); i++) if (key_origin_list[i].origin == origin) return key_origin_list[i].name; return "?"; } /* Returns true if a secret key is available for the public key with key id KEYID; returns false if not. This function ignores legacy keys. Note: this is just a fast check and does not tell us whether the secret key is valid; this check merely indicates whether there is some secret key with the specified key id. */ int have_secret_key_with_kid (ctrl_t ctrl, u32 *keyid) { gpg_error_t err; KEYDB_HANDLE kdbhd; KEYDB_SEARCH_DESC desc; kbnode_t keyblock; kbnode_t node; int result = 0; kdbhd = keydb_new (ctrl); if (!kdbhd) return 0; memset (&desc, 0, sizeof desc); desc.mode = KEYDB_SEARCH_MODE_LONG_KID; desc.u.kid[0] = keyid[0]; desc.u.kid[1] = keyid[1]; while (!result) { err = keydb_search (kdbhd, &desc, 1, NULL); if (err) break; err = keydb_get_keyblock (kdbhd, &keyblock); if (err) { log_error (_("error reading keyblock: %s\n"), gpg_strerror (err)); break; } for (node = keyblock; node; node = node->next) { /* Bit 0 of the flags is set if the search found the key using that key or subkey. Note: a search will only ever match a single key or subkey. */ if ((node->flag & 1)) { log_assert (node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_PUBLIC_SUBKEY); if (agent_probe_secret_key (NULL, node->pkt->pkt.public_key)) result = 1; /* Secret key available. */ else result = 0; break; } } release_kbnode (keyblock); } keydb_release (kdbhd); return result; } diff --git a/g10/mainproc.c b/g10/mainproc.c index 03573c921..7d8520c6c 100644 --- a/g10/mainproc.c +++ b/g10/mainproc.c @@ -1,2803 +1,2803 @@ /* mainproc.c - handle packets * Copyright (C) 1998-2009 Free Software Foundation, Inc. * Copyright (C) 2013-2014 Werner Koch * Copyright (C) 2020 g10 Code GmbH * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include #include #include #include #include #include "gpg.h" #include "../common/util.h" #include "packet.h" #include "../common/iobuf.h" #include "options.h" #include "keydb.h" #include "filter.h" #include "main.h" #include "../common/status.h" #include "../common/i18n.h" #include "trustdb.h" #include "keyserver-internal.h" #include "photoid.h" #include "../common/mbox-util.h" #include "call-dirmngr.h" #include "../common/compliance.h" /* Put an upper limit on nested packets. The 32 is an arbitrary value, a much lower should actually be sufficient. */ #define MAX_NESTING_DEPTH 32 /* * Object to hold the processing context. */ typedef struct mainproc_context *CTX; struct mainproc_context { ctrl_t ctrl; struct mainproc_context *anchor; /* May be useful in the future. */ PKT_public_key *last_pubkey; PKT_user_id *last_user_id; md_filter_context_t mfx; int sigs_only; /* Process only signatures and reject all other stuff. */ int encrypt_only; /* Process only encryption messages. */ /* Name of the file with the complete signature or the file with the detached signature. This is currently only used to deduce the file name of the data file if that has not been given. */ const char *sigfilename; /* A structure to describe the signed data in case of a detached signature. */ struct { /* A file descriptor of the signed data. Only used if not -1. */ int data_fd; /* A list of filenames with the data files or NULL. This is only used if DATA_FD is -1. */ strlist_t data_names; /* Flag to indicated that either one of the next previous fields is used. This is only needed for better readability. */ int used; } signed_data; DEK *dek; int last_was_session_key; kbnode_t list; /* The current list of packets. */ iobuf_t iobuf; /* Used to get the filename etc. */ int trustletter; /* Temporary usage in list_node. */ ulong symkeys; /* Number of symmetrically encrypted session keys. */ struct pubkey_enc_list *pkenc_list; /* List of encryption packets. */ int seen_pkt_encrypted_aead; /* PKT_ENCRYPTED_AEAD packet seen. */ struct { unsigned int sig_seen:1; /* Set to true if a signature packet has been seen. */ unsigned int data:1; /* Any data packet seen */ unsigned int uncompress_failed:1; } any; }; /* Counter with the number of literal data packets seen. Note that * this is also bumped at the end of an encryption. This counter is * used for a basic consistency check of a received PGP message. */ static int literals_seen; /*** Local prototypes. ***/ static int do_proc_packets (CTX c, iobuf_t a); static void list_node (CTX c, kbnode_t node); static void proc_tree (CTX c, kbnode_t node); /*** Functions. ***/ /* Reset the literal data counter. This is required to setup a new * decryption or verification context. */ void reset_literals_seen(void) { literals_seen = 0; } static void release_list( CTX c ) { proc_tree (c, c->list); release_kbnode (c->list); while (c->pkenc_list) { struct pubkey_enc_list *tmp = c->pkenc_list->next; mpi_release (c->pkenc_list->data[0]); mpi_release (c->pkenc_list->data[1]); xfree (c->pkenc_list); c->pkenc_list = tmp; } c->pkenc_list = NULL; c->list = NULL; c->any.data = 0; c->any.uncompress_failed = 0; c->last_was_session_key = 0; c->seen_pkt_encrypted_aead = 0; xfree (c->dek); c->dek = NULL; } static int add_onepass_sig (CTX c, PACKET *pkt) { kbnode_t node; if (c->list) /* Add another packet. */ add_kbnode (c->list, new_kbnode (pkt)); else /* Insert the first one. */ c->list = node = new_kbnode (pkt); return 1; } static int add_gpg_control (CTX c, PACKET *pkt) { if ( pkt->pkt.gpg_control->control == CTRLPKT_CLEARSIGN_START ) { /* New clear text signature. * Process the last one and reset everything */ release_list(c); } if (c->list) /* Add another packet. */ add_kbnode (c->list, new_kbnode (pkt)); else /* Insert the first one. */ c->list = new_kbnode (pkt); return 1; } static int add_user_id (CTX c, PACKET *pkt) { if (!c->list) { log_error ("orphaned user ID\n"); return 0; } add_kbnode (c->list, new_kbnode (pkt)); return 1; } static int add_subkey (CTX c, PACKET *pkt) { if (!c->list) { log_error ("subkey w/o mainkey\n"); return 0; } add_kbnode (c->list, new_kbnode (pkt)); return 1; } static int add_ring_trust (CTX c, PACKET *pkt) { if (!c->list) { log_error ("ring trust w/o key\n"); return 0; } add_kbnode (c->list, new_kbnode (pkt)); return 1; } static int add_signature (CTX c, PACKET *pkt) { kbnode_t node; c->any.sig_seen = 1; if (pkt->pkttype == PKT_SIGNATURE && !c->list) { /* This is the first signature for the following datafile. * GPG does not write such packets; instead it always uses * onepass-sig packets. The drawback of PGP's method * of prepending the signature to the data is * that it is not possible to make a signature from data read * from stdin. (GPG is able to read PGP stuff anyway.) */ node = new_kbnode (pkt); c->list = node; return 1; } else if (!c->list) return 0; /* oops (invalid packet sequence)*/ else if (!c->list->pkt) BUG(); /* so nicht */ /* Add a new signature node item at the end. */ node = new_kbnode (pkt); add_kbnode (c->list, node); return 1; } static gpg_error_t symkey_decrypt_seskey (DEK *dek, byte *seskey, size_t slen) { gpg_error_t err; gcry_cipher_hd_t hd; unsigned int noncelen, keylen; enum gcry_cipher_modes ciphermode; if (dek->use_aead) { err = openpgp_aead_algo_info (dek->use_aead, &ciphermode, &noncelen); if (err) return err; } else { ciphermode = GCRY_CIPHER_MODE_CFB; noncelen = 0; } /* Check that the session key has a size of 16 to 32 bytes. */ if ((dek->use_aead && (slen < (noncelen + 16 + 16) || slen > (noncelen + 32 + 16))) || (!dek->use_aead && (slen < 17 || slen > 33))) { log_error ( _("weird size for an encrypted session key (%d)\n"), (int)slen); return gpg_error (GPG_ERR_BAD_KEY); } err = openpgp_cipher_open (&hd, dek->algo, ciphermode, GCRY_CIPHER_SECURE); if (!err) err = gcry_cipher_setkey (hd, dek->key, dek->keylen); if (!err) err = gcry_cipher_setiv (hd, noncelen? seskey : NULL, noncelen); if (err) goto leave; if (dek->use_aead) { byte ad[4]; ad[0] = (0xc0 | PKT_SYMKEY_ENC); ad[1] = 5; ad[2] = dek->algo; ad[3] = dek->use_aead; err = gcry_cipher_authenticate (hd, ad, 4); if (err) goto leave; gcry_cipher_final (hd); keylen = slen - noncelen - 16; err = gcry_cipher_decrypt (hd, seskey+noncelen, keylen, NULL, 0); if (err) goto leave; err = gcry_cipher_checktag (hd, seskey+noncelen+keylen, 16); if (err) goto leave; /* Now we replace the dek components with the real session key to * decrypt the contents of the sequencing packet. */ if (keylen > DIM(dek->key)) { err = gpg_error (GPG_ERR_TOO_LARGE); goto leave; } dek->keylen = keylen; memcpy (dek->key, seskey + noncelen, dek->keylen); } else { gcry_cipher_decrypt (hd, seskey, slen, NULL, 0 ); /* Here we can only test whether the algo given in decrypted * session key is a valid OpenPGP algo. With 11 defined * symmetric algorithms we will miss 4.3% of wrong passphrases * here. The actual checking is done later during bulk * decryption; we can't bring this check forward easily. We * need to use the GPG_ERR_CHECKSUM so that we won't run into * the gnupg < 2.2 bug compatible case which would terminate the * process on GPG_ERR_CIPHER_ALGO. Note that with AEAD (above) * we will have a reliable test here. */ if (openpgp_cipher_test_algo (seskey[0]) || openpgp_cipher_get_algo_keylen (seskey[0]) != slen - 1) { err = gpg_error (GPG_ERR_CHECKSUM); goto leave; } /* Now we replace the dek components with the real session key to * decrypt the contents of the sequencing packet. */ keylen = slen-1; if (keylen > DIM(dek->key)) { err = gpg_error (GPG_ERR_TOO_LARGE); goto leave; } dek->algo = seskey[0]; dek->keylen = keylen; memcpy (dek->key, seskey + 1, dek->keylen); } /*log_hexdump( "thekey", dek->key, dek->keylen );*/ leave: gcry_cipher_close (hd); return err; } static void proc_symkey_enc (CTX c, PACKET *pkt) { gpg_error_t err; PKT_symkey_enc *enc; enc = pkt->pkt.symkey_enc; if (!enc) log_error ("invalid symkey encrypted packet\n"); else if(!c->dek) { int algo = enc->cipher_algo; const char *s = openpgp_cipher_algo_name (algo); const char *a = (enc->aead_algo ? openpgp_aead_algo_name (enc->aead_algo) /**/ : "CFB"); if (!openpgp_cipher_test_algo (algo)) { if (!opt.quiet) { if (enc->seskeylen) log_info (_("%s.%s encrypted session key\n"), s, a ); else log_info (_("%s.%s encrypted data\n"), s, a ); } } else log_error (_("encrypted with unknown algorithm %d.%s\n"), algo, a); if (openpgp_md_test_algo (enc->s2k.hash_algo)) { log_error(_("passphrase generated with unknown digest" " algorithm %d\n"),enc->s2k.hash_algo); s = NULL; } c->last_was_session_key = 2; if (!s || opt.list_only) goto leave; if (opt.override_session_key) { c->dek = xmalloc_clear (sizeof *c->dek); if (get_override_session_key (c->dek, opt.override_session_key)) { xfree (c->dek); c->dek = NULL; } } else { c->dek = passphrase_to_dek (algo, &enc->s2k, 0, 0, NULL, NULL); if (c->dek) { c->dek->symmetric = 1; c->dek->use_aead = enc->aead_algo; /* FIXME: This doesn't work perfectly if a symmetric key comes before a public key in the message - if the user doesn't know the passphrase, then there is a chance that the "decrypted" algorithm will happen to be a valid one, which will make the returned dek appear valid, so we won't try any public keys that come later. */ if (enc->seskeylen) { err = symkey_decrypt_seskey (c->dek, enc->seskey, enc->seskeylen); if (err) { log_info ("decryption of the symmetrically encrypted" " session key failed: %s\n", gpg_strerror (err)); if (gpg_err_code (err) != GPG_ERR_BAD_KEY && gpg_err_code (err) != GPG_ERR_CHECKSUM) log_fatal ("process terminated to be bug compatible" " with GnuPG <= 2.2\n"); if (c->dek->s2k_cacheid[0]) { if (opt.debug) log_debug ("cleared passphrase cached with ID:" " %s\n", c->dek->s2k_cacheid); passphrase_clear_cache (c->dek->s2k_cacheid); } xfree (c->dek); c->dek = NULL; } } else c->dek->algo_info_printed = 1; } } } leave: c->symkeys++; free_packet (pkt, NULL); } static void proc_pubkey_enc (CTX c, PACKET *pkt) { PKT_pubkey_enc *enc; /* Check whether the secret key is available and store in this case. */ c->last_was_session_key = 1; enc = pkt->pkt.pubkey_enc; /*printf("enc: encrypted by a pubkey with keyid %08lX\n", enc->keyid[1] );*/ /* Hmmm: why do I have this algo check here - anyway there is * function to check it. */ if (opt.verbose) log_info (_("public key is %s\n"), keystr (enc->keyid)); if (is_status_enabled ()) { char buf[50]; snprintf (buf, sizeof buf, "%08lX%08lX %d 0", (ulong)enc->keyid[0], (ulong)enc->keyid[1], enc->pubkey_algo); write_status_text (STATUS_ENC_TO, buf); } if (!opt.list_only && !opt.override_session_key) { struct pubkey_enc_list *x = xmalloc (sizeof *x); x->keyid[0] = enc->keyid[0]; x->keyid[1] = enc->keyid[1]; x->pubkey_algo = enc->pubkey_algo; x->result = -1; x->data[0] = x->data[1] = NULL; if (enc->data[0]) { x->data[0] = mpi_copy (enc->data[0]); x->data[1] = mpi_copy (enc->data[1]); } x->next = c->pkenc_list; c->pkenc_list = x; } free_packet(pkt, NULL); } /* * Print the list of public key encrypted packets which we could * not decrypt. */ static void print_pkenc_list (ctrl_t ctrl, struct pubkey_enc_list *list) { for (; list; list = list->next) { PKT_public_key *pk; char pkstrbuf[PUBKEY_STRING_SIZE]; char *p; pk = xmalloc_clear (sizeof *pk); pk->pubkey_algo = list->pubkey_algo; if (!get_pubkey (ctrl, pk, list->keyid)) { pubkey_string (pk, pkstrbuf, sizeof pkstrbuf); log_info (_("encrypted with %s key, ID %s, created %s\n"), pkstrbuf, keystr_from_pk (pk), strtimestamp (pk->timestamp)); p = get_user_id_native (ctrl, list->keyid); log_printf (_(" \"%s\"\n"), p); xfree (p); } else log_info (_("encrypted with %s key, ID %s\n"), openpgp_pk_algo_name (list->pubkey_algo), keystr(list->keyid)); free_public_key (pk); } } static void proc_encrypted (CTX c, PACKET *pkt) { int result = 0; int early_plaintext = literals_seen; if (pkt->pkttype == PKT_ENCRYPTED_AEAD) c->seen_pkt_encrypted_aead = 1; if (early_plaintext) { log_info (_("WARNING: multiple plaintexts seen\n")); write_status_errcode ("decryption.early_plaintext", GPG_ERR_BAD_DATA); /* We fail only later so that we can print some more info first. */ } if (!opt.quiet) { if (c->symkeys>1) log_info (_("encrypted with %lu passphrases\n"), c->symkeys); else if (c->symkeys == 1) log_info (_("encrypted with 1 passphrase\n")); print_pkenc_list (c->ctrl, c->pkenc_list); } /* Figure out the session key by looking at all pkenc packets. */ if (opt.list_only || c->dek) ; else if (opt.override_session_key) { c->dek = xmalloc_clear (sizeof *c->dek); result = get_override_session_key (c->dek, opt.override_session_key); if (result) { xfree (c->dek); c->dek = NULL; log_info (_("public key decryption failed: %s\n"), gpg_strerror (result)); write_status_error ("pkdecrypt_failed", result); } } else if (c->pkenc_list) { c->dek = xmalloc_secure_clear (sizeof *c->dek); result = get_session_key (c->ctrl, c->pkenc_list, c->dek); if (is_status_enabled ()) { struct pubkey_enc_list *list; for (list = c->pkenc_list; list; list = list->next) if (list->result && list->result != -1) { char buf[20]; snprintf (buf, sizeof buf, "%08lX%08lX", (ulong)list->keyid[0], (ulong)list->keyid[1]); write_status_text (STATUS_NO_SECKEY, buf); } } if (result) { log_info (_("public key decryption failed: %s\n"), gpg_strerror (result)); write_status_error ("pkdecrypt_failed", result); /* Error: Delete the DEK. */ xfree (c->dek); c->dek = NULL; } } if (c->dek && opt.verbose > 1) log_info (_("public key encrypted data: good DEK\n")); write_status (STATUS_BEGIN_DECRYPTION); /*log_debug("dat: %sencrypted data\n", c->dek?"":"conventional ");*/ if (opt.list_only) result = -1; else if (!c->dek && !c->last_was_session_key) { int algo; STRING2KEY s2kbuf; STRING2KEY *s2k = NULL; int canceled; if (opt.override_session_key) { c->dek = xmalloc_clear (sizeof *c->dek); result = get_override_session_key (c->dek, opt.override_session_key); if (result) { xfree (c->dek); c->dek = NULL; } } else { /* Assume this is old style conventional encrypted data. */ algo = opt.def_cipher_algo; if (algo) log_info (_("assuming %s encrypted data\n"), openpgp_cipher_algo_name (algo)); else if (openpgp_cipher_test_algo (CIPHER_ALGO_IDEA)) { algo = opt.def_cipher_algo; if (!algo) algo = opt.s2k_cipher_algo; log_info (_("IDEA cipher unavailable, " "optimistically attempting to use %s instead\n"), openpgp_cipher_algo_name (algo)); } else { algo = CIPHER_ALGO_IDEA; if (!opt.s2k_digest_algo) { /* If no digest is given we assume SHA-1. */ s2kbuf.mode = 0; s2kbuf.hash_algo = DIGEST_ALGO_SHA1; s2k = &s2kbuf; } log_info (_("assuming %s encrypted data\n"), "IDEA"); } c->dek = passphrase_to_dek (algo, s2k, 0, 0, NULL, &canceled); if (c->dek) c->dek->algo_info_printed = 1; else if (canceled) result = gpg_error (GPG_ERR_CANCELED); else result = gpg_error (GPG_ERR_INV_PASSPHRASE); } } else if (!c->dek) { if (c->symkeys && !c->pkenc_list) result = gpg_error (GPG_ERR_BAD_KEY); if (!result) result = gpg_error (GPG_ERR_NO_SECKEY); } /* Compute compliance with CO_DE_VS. */ if (!result && is_status_enabled () /* Symmetric encryption and asymmetric encryption voids compliance. */ && (c->symkeys != !!c->pkenc_list ) /* Overriding session key voids compliance. */ && !opt.override_session_key /* Check symmetric cipher. */ && gnupg_cipher_is_compliant (CO_DE_VS, c->dek->algo, GCRY_CIPHER_MODE_CFB)) { struct pubkey_enc_list *i; int compliant = 1; PKT_public_key *pk = xmalloc (sizeof *pk); if ( !(c->pkenc_list || c->symkeys) ) log_debug ("%s: where else did the session key come from?\n", __func__); /* Now check that every key used to encrypt the session key is * compliant. */ for (i = c->pkenc_list; i && compliant; i = i->next) { memset (pk, 0, sizeof *pk); pk->pubkey_algo = i->pubkey_algo; if (get_pubkey (c->ctrl, pk, i->keyid) != 0 || ! gnupg_pk_is_compliant (CO_DE_VS, pk->pubkey_algo, pk->pkey, nbits_from_pk (pk), NULL)) compliant = 0; release_public_key_parts (pk); } xfree (pk); if (compliant) write_status_strings (STATUS_DECRYPTION_COMPLIANCE_MODE, gnupg_status_compliance_flag (CO_DE_VS), NULL); } if (!result) result = decrypt_data (c->ctrl, c, pkt->pkt.encrypted, c->dek ); /* Trigger the deferred error. */ if (!result && early_plaintext) result = gpg_error (GPG_ERR_BAD_DATA); if (result == -1) ; else if (!result && !opt.ignore_mdc_error && !pkt->pkt.encrypted->mdc_method && !pkt->pkt.encrypted->aead_algo) { /* The message has been decrypted but does not carry an MDC or * uses AEAD encryption. --ignore-mdc-error has also not been * used. To avoid attacks changing an MDC message to a non-MDC * message, we fail here. */ log_error (_("WARNING: message was not integrity protected\n")); if (!pkt->pkt.encrypted->mdc_method && (openpgp_cipher_get_algo_blklen (c->dek->algo) == 8 || c->dek->algo == CIPHER_ALGO_TWOFISH)) { /* Before 2.2.8 we did not fail hard for a missing MDC if * one of the old ciphers where used. Although these cases * are rare in practice we print a hint on how to decrypt * such messages. */ log_string (GPGRT_LOGLVL_INFO, _("Hint: If this message was created before the year 2003 it is\n" "likely that this message is legitimate. This is because back\n" "then integrity protection was not widely used.\n")); log_info (_("Use the option '%s' to decrypt anyway.\n"), "--ignore-mdc-error"); write_status_errcode ("nomdc_with_legacy_cipher", GPG_ERR_DECRYPT_FAILED); } log_info (_("decryption forced to fail!\n")); write_status (STATUS_DECRYPTION_FAILED); } else if (!result || (gpg_err_code (result) == GPG_ERR_BAD_SIGNATURE && !pkt->pkt.encrypted->aead_algo && opt.ignore_mdc_error)) { /* All is fine or for an MDC message the MDC failed but the * --ignore-mdc-error option is active. For compatibility * reasons we issue GOODMDC also for AEAD messages. */ write_status (STATUS_DECRYPTION_OKAY); if (opt.verbose > 1) log_info(_("decryption okay\n")); if (pkt->pkt.encrypted->aead_algo) write_status (STATUS_GOODMDC); else if (pkt->pkt.encrypted->mdc_method && !result) write_status (STATUS_GOODMDC); else log_info (_("WARNING: message was not integrity protected\n")); } else if (gpg_err_code (result) == GPG_ERR_BAD_SIGNATURE || gpg_err_code (result) == GPG_ERR_TRUNCATED) { glo_ctrl.lasterr = result; log_error (_("WARNING: encrypted message has been manipulated!\n")); write_status (STATUS_BADMDC); write_status (STATUS_DECRYPTION_FAILED); } else { if ((gpg_err_code (result) == GPG_ERR_BAD_KEY || gpg_err_code (result) == GPG_ERR_CHECKSUM || gpg_err_code (result) == GPG_ERR_CIPHER_ALGO) && c->dek && *c->dek->s2k_cacheid != '\0') { if (opt.debug) log_debug ("cleared passphrase cached with ID: %s\n", c->dek->s2k_cacheid); passphrase_clear_cache (c->dek->s2k_cacheid); } glo_ctrl.lasterr = result; write_status (STATUS_DECRYPTION_FAILED); log_error (_("decryption failed: %s\n"), gpg_strerror (result)); /* Hmmm: does this work when we have encrypted using multiple * ways to specify the session key (symmmetric and PK). */ } xfree (c->dek); c->dek = NULL; free_packet (pkt, NULL); c->last_was_session_key = 0; write_status (STATUS_END_DECRYPTION); /* Bump the counter even if we have not seen a literal data packet * inside an encryption container. This acts as a sentinel in case * a misplace extra literal data packets follows after this * encrypted packet. */ literals_seen++; } static int have_seen_pkt_encrypted_aead( CTX c ) { CTX cc; for (cc = c; cc; cc = cc->anchor) { if (cc->seen_pkt_encrypted_aead) return 1; } return 0; } static void proc_plaintext( CTX c, PACKET *pkt ) { PKT_plaintext *pt = pkt->pkt.plaintext; int any, clearsig, rc; kbnode_t n; unsigned char *extrahash; size_t extrahashlen; /* This is a literal data packet. Bump a counter for later checks. */ literals_seen++; if (pt->namelen == 8 && !memcmp( pt->name, "_CONSOLE", 8)) log_info (_("Note: sender requested \"for-your-eyes-only\"\n")); else if (opt.verbose) { /* We don't use print_utf8_buffer because that would require a * string change which we don't want in 2.2. It is also not * clear whether the filename is always utf-8 encoded. */ char *tmp = make_printable_string (pt->name, pt->namelen, 0); log_info (_("original file name='%.*s'\n"), (int)strlen (tmp), tmp); xfree (tmp); } free_md_filter_context (&c->mfx); if (gcry_md_open (&c->mfx.md, 0, 0)) BUG (); /* fixme: we may need to push the textfilter if we have sigclass 1 * and no armoring - Not yet tested * Hmmm, why don't we need it at all if we have sigclass 1 * Should we assume that plaintext in mode 't' has always sigclass 1?? * See: Russ Allbery's mail 1999-02-09 */ any = clearsig = 0; for (n=c->list; n; n = n->next ) { if (n->pkt->pkttype == PKT_ONEPASS_SIG) { /* The onepass signature case. */ if (n->pkt->pkt.onepass_sig->digest_algo) { if (!opt.skip_verify) gcry_md_enable (c->mfx.md, n->pkt->pkt.onepass_sig->digest_algo); any = 1; } } else if (n->pkt->pkttype == PKT_GPG_CONTROL && n->pkt->pkt.gpg_control->control == CTRLPKT_CLEARSIGN_START) { /* The clearsigned message case. */ size_t datalen = n->pkt->pkt.gpg_control->datalen; const byte *data = n->pkt->pkt.gpg_control->data; /* Check that we have at least the sigclass and one hash. */ if (datalen < 2) log_fatal ("invalid control packet CTRLPKT_CLEARSIGN_START\n"); /* Note that we don't set the clearsig flag for not-dash-escaped * documents. */ clearsig = (*data == 0x01); for (data++, datalen--; datalen; datalen--, data++) if (!opt.skip_verify) gcry_md_enable (c->mfx.md, *data); any = 1; break; /* Stop here as one-pass signature packets are not expected. */ } else if (n->pkt->pkttype == PKT_SIGNATURE) { /* The SIG+LITERAL case that PGP used to use. */ if (!opt.skip_verify) gcry_md_enable (c->mfx.md, n->pkt->pkt.signature->digest_algo); any = 1; } } if (!any && !opt.skip_verify && !have_seen_pkt_encrypted_aead(c)) { /* This is for the old GPG LITERAL+SIG case. It's not legal according to 2440, so hopefully it won't come up that often. There is no good way to specify what algorithms to use in that case, so these there are the historical answer. */ gcry_md_enable (c->mfx.md, DIGEST_ALGO_RMD160); gcry_md_enable (c->mfx.md, DIGEST_ALGO_SHA1); } if (DBG_HASHING) { gcry_md_debug (c->mfx.md, "verify"); if (c->mfx.md2) gcry_md_debug (c->mfx.md2, "verify2"); } rc=0; if (literals_seen > 1) { log_info (_("WARNING: multiple plaintexts seen\n")); write_status_text (STATUS_ERROR, "proc_pkt.plaintext 89_BAD_DATA"); log_inc_errorcount (); rc = gpg_error (GPG_ERR_UNEXPECTED); } if (!rc) { /* It we are in --verify mode, we do not want to output the * signed text. However, if --output is also used we do what * has been requested and write out the signed data. */ rc = handle_plaintext (pt, &c->mfx, (opt.outfp || opt.outfile)? 0 : c->sigs_only, clearsig); if (gpg_err_code (rc) == GPG_ERR_EACCES && !c->sigs_only) { /* Can't write output but we hash it anyway to check the signature. */ rc = handle_plaintext( pt, &c->mfx, 1, clearsig ); } } if (rc) log_error ("handle plaintext failed: %s\n", gpg_strerror (rc)); /* We add a marker control packet instead of the plaintext packet. * This is so that we can later detect invalid packet sequences. * The packet is further used to convey extra data from the * plaintext packet to the signature verification. */ extrahash = xtrymalloc (6 + pt->namelen); if (!extrahash) { /* No way to return an error. */ rc = gpg_error_from_syserror (); log_error ("malloc failed in %s: %s\n", __func__, gpg_strerror (rc)); extrahashlen = 0; } else { extrahash[0] = pt->mode; extrahash[1] = pt->namelen; if (pt->namelen) memcpy (extrahash+2, pt->name, pt->namelen); extrahashlen = 2 + pt->namelen; extrahash[extrahashlen++] = pt->timestamp >> 24; extrahash[extrahashlen++] = pt->timestamp >> 16; extrahash[extrahashlen++] = pt->timestamp >> 8; extrahash[extrahashlen++] = pt->timestamp ; } free_packet (pkt, NULL); c->last_was_session_key = 0; n = new_kbnode (create_gpg_control (CTRLPKT_PLAINTEXT_MARK, extrahash, extrahashlen)); xfree (extrahash); if (c->list) add_kbnode (c->list, n); else c->list = n; } static int proc_compressed_cb (iobuf_t a, void *info) { if ( ((CTX)info)->signed_data.used && ((CTX)info)->signed_data.data_fd != -1) return proc_signature_packets_by_fd (((CTX)info)->ctrl, info, a, ((CTX)info)->signed_data.data_fd); else return proc_signature_packets (((CTX)info)->ctrl, info, a, ((CTX)info)->signed_data.data_names, ((CTX)info)->sigfilename ); } static int proc_encrypt_cb (iobuf_t a, void *info ) { CTX c = info; return proc_encryption_packets (c->ctrl, info, a ); } static int proc_compressed (CTX c, PACKET *pkt) { PKT_compressed *zd = pkt->pkt.compressed; int rc; /*printf("zip: compressed data packet\n");*/ if (c->sigs_only) rc = handle_compressed (c->ctrl, c, zd, proc_compressed_cb, c); else if( c->encrypt_only ) rc = handle_compressed (c->ctrl, c, zd, proc_encrypt_cb, c); else rc = handle_compressed (c->ctrl, c, zd, NULL, NULL); if (gpg_err_code (rc) == GPG_ERR_BAD_DATA) { if (!c->any.uncompress_failed) { CTX cc; for (cc=c; cc; cc = cc->anchor) cc->any.uncompress_failed = 1; log_error ("uncompressing failed: %s\n", gpg_strerror (rc)); } } else if (rc) log_error ("uncompressing failed: %s\n", gpg_strerror (rc)); free_packet (pkt, NULL); c->last_was_session_key = 0; return rc; } /* * Check the signature. If R_PK is not NULL a copy of the public key * used to verify the signature will be stored there, or NULL if not * found. If FORCED_PK is not NULL, this public key is used to verify * _data signatures_ and no key lookup is done. Returns: 0 = valid * signature or an error code */ static int do_check_sig (CTX c, kbnode_t node, const void *extrahash, size_t extrahashlen, PKT_public_key *forced_pk, int *is_selfsig, int *is_expkey, int *is_revkey, PKT_public_key **r_pk) { PKT_signature *sig; gcry_md_hd_t md = NULL; gcry_md_hd_t md2 = NULL; gcry_md_hd_t md_good = NULL; int algo, rc; if (r_pk) *r_pk = NULL; log_assert (node->pkt->pkttype == PKT_SIGNATURE); if (is_selfsig) *is_selfsig = 0; sig = node->pkt->pkt.signature; algo = sig->digest_algo; rc = openpgp_md_test_algo (algo); if (rc) return rc; if (sig->sig_class == 0x00) { if (c->mfx.md) { if (gcry_md_copy (&md, c->mfx.md )) BUG (); } else /* detached signature */ { /* check_signature() will enable the md. */ if (gcry_md_open (&md, 0, 0 )) BUG (); } } else if (sig->sig_class == 0x01) { /* How do we know that we have to hash the (already hashed) text in canonical mode ??? (calculating both modes???) */ if (c->mfx.md) { if (gcry_md_copy (&md, c->mfx.md )) BUG (); if (c->mfx.md2 && gcry_md_copy (&md2, c->mfx.md2)) BUG (); } else /* detached signature */ { log_debug ("Do we really need this here?"); /* check_signature() will enable the md*/ if (gcry_md_open (&md, 0, 0 )) BUG (); if (gcry_md_open (&md2, 0, 0 )) BUG (); } } else if ((sig->sig_class&~3) == 0x10 || sig->sig_class == 0x18 || sig->sig_class == 0x1f || sig->sig_class == 0x20 || sig->sig_class == 0x28 || sig->sig_class == 0x30) { if (c->list->pkt->pkttype == PKT_PUBLIC_KEY || c->list->pkt->pkttype == PKT_PUBLIC_SUBKEY) { return check_key_signature (c->ctrl, c->list, node, is_selfsig); } else if (sig->sig_class == 0x20) { log_error (_("standalone revocation - " "use \"gpg --import\" to apply\n")); return GPG_ERR_NOT_PROCESSED; } else { log_error ("invalid root packet for sigclass %02x\n", sig->sig_class); return GPG_ERR_SIG_CLASS; } } else return GPG_ERR_SIG_CLASS; /* We only get here if we are checking the signature of a binary (0x00) or text document (0x01). */ rc = check_signature2 (c->ctrl, sig, md, extrahash, extrahashlen, forced_pk, NULL, is_expkey, is_revkey, r_pk); if (! rc) md_good = md; else if (gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE && md2) { PKT_public_key *pk2; rc = check_signature2 (c->ctrl, sig, md2, extrahash, extrahashlen, forced_pk, NULL, is_expkey, is_revkey, r_pk? &pk2 : NULL); if (!rc) { md_good = md2; if (r_pk) { free_public_key (*r_pk); *r_pk = pk2; } } } if (md_good) { unsigned char *buffer = gcry_md_read (md_good, sig->digest_algo); sig->digest_len = gcry_md_get_algo_dlen (map_md_openpgp_to_gcry (algo)); memcpy (sig->digest, buffer, sig->digest_len); } gcry_md_close (md); gcry_md_close (md2); return rc; } static void print_userid (PACKET *pkt) { if (!pkt) BUG(); if (pkt->pkttype != PKT_USER_ID) { es_printf ("ERROR: unexpected packet type %d", pkt->pkttype ); return; } if (opt.with_colons) { if (pkt->pkt.user_id->attrib_data) es_printf("%u %lu", pkt->pkt.user_id->numattribs, pkt->pkt.user_id->attrib_len); else es_write_sanitized (es_stdout, pkt->pkt.user_id->name, pkt->pkt.user_id->len, ":", NULL); } else print_utf8_buffer (es_stdout, pkt->pkt.user_id->name, pkt->pkt.user_id->len ); } /* * List the keyblock in a user friendly way */ static void list_node (CTX c, kbnode_t node) { if (!node) ; else if (node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_PUBLIC_SUBKEY) { PKT_public_key *pk = node->pkt->pkt.public_key; if (opt.with_colons) { u32 keyid[2]; keyid_from_pk( pk, keyid ); if (pk->flags.primary) c->trustletter = (opt.fast_list_mode ? 0 : get_validity_info (c->ctrl, node->pkt->pkttype == PKT_PUBLIC_KEY ? node : NULL, pk, NULL)); es_printf ("%s:", pk->flags.primary? "pub":"sub" ); if (c->trustletter) es_putc (c->trustletter, es_stdout); es_printf (":%u:%d:%08lX%08lX:%s:%s::", nbits_from_pk( pk ), pk->pubkey_algo, (ulong)keyid[0],(ulong)keyid[1], colon_datestr_from_pk( pk ), colon_strtime (pk->expiredate) ); if (pk->flags.primary && !opt.fast_list_mode) es_putc (get_ownertrust_info (c->ctrl, pk, 1), es_stdout); es_putc (':', es_stdout); es_putc ('\n', es_stdout); } else { print_key_line (c->ctrl, es_stdout, pk, 0); } if (opt.keyid_format == KF_NONE && !opt.with_colons) ; /* Already printed. */ else if ((pk->flags.primary && opt.fingerprint) || opt.fingerprint > 1) print_fingerprint (c->ctrl, NULL, pk, 0); if (pk->flags.primary) { int kl = opt.keyid_format == KF_NONE? 0 : keystrlen (); /* Now list all userids with their signatures. */ for (node = node->next; node; node = node->next) { if (node->pkt->pkttype == PKT_SIGNATURE) { list_node (c, node ); } else if (node->pkt->pkttype == PKT_USER_ID) { if (opt.with_colons) es_printf ("%s:::::::::", node->pkt->pkt.user_id->attrib_data?"uat":"uid"); else es_printf ("uid%*s", kl + (opt.legacy_list_mode? 9:11), "" ); print_userid (node->pkt); if (opt.with_colons) es_putc (':', es_stdout); es_putc ('\n', es_stdout); } else if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY) { list_node(c, node ); } } } } else if (node->pkt->pkttype == PKT_SECRET_KEY || node->pkt->pkttype == PKT_SECRET_SUBKEY) { log_debug ("FIXME: No way to print secret key packets here\n"); /* fixme: We may use a function to turn a secret key packet into a public key one and use that here. */ } else if (node->pkt->pkttype == PKT_SIGNATURE) { PKT_signature *sig = node->pkt->pkt.signature; int is_selfsig = 0; int rc2 = 0; size_t n; char *p; int sigrc = ' '; if (!opt.verbose) return; if (sig->sig_class == 0x20 || sig->sig_class == 0x30) es_fputs ("rev", es_stdout); else es_fputs ("sig", es_stdout); if (opt.check_sigs) { fflush (stdout); rc2 = do_check_sig (c, node, NULL, 0, NULL, &is_selfsig, NULL, NULL, NULL); switch (gpg_err_code (rc2)) { case 0: sigrc = '!'; break; case GPG_ERR_BAD_SIGNATURE: sigrc = '-'; break; case GPG_ERR_NO_PUBKEY: case GPG_ERR_UNUSABLE_PUBKEY: sigrc = '?'; break; default: sigrc = '%'; break; } } else /* Check whether this is a self signature. */ { u32 keyid[2]; if (c->list->pkt->pkttype == PKT_PUBLIC_KEY || c->list->pkt->pkttype == PKT_SECRET_KEY ) { keyid_from_pk (c->list->pkt->pkt.public_key, keyid); if (keyid[0] == sig->keyid[0] && keyid[1] == sig->keyid[1]) is_selfsig = 1; } } if (opt.with_colons) { es_putc (':', es_stdout); if (sigrc != ' ') es_putc (sigrc, es_stdout); es_printf ("::%d:%08lX%08lX:%s:%s:", sig->pubkey_algo, (ulong)sig->keyid[0], (ulong)sig->keyid[1], colon_datestr_from_sig (sig), colon_expirestr_from_sig (sig)); if (sig->trust_depth || sig->trust_value) es_printf ("%d %d",sig->trust_depth,sig->trust_value); es_putc (':', es_stdout); if (sig->trust_regexp) es_write_sanitized (es_stdout, sig->trust_regexp, strlen (sig->trust_regexp), ":", NULL); es_putc (':', es_stdout); } else es_printf ("%c %s %s ", sigrc, keystr (sig->keyid), datestr_from_sig(sig)); if (sigrc == '%') es_printf ("[%s] ", gpg_strerror (rc2) ); else if (sigrc == '?') ; else if (is_selfsig) { if (opt.with_colons) es_putc (':', es_stdout); es_fputs (sig->sig_class == 0x18? "[keybind]":"[selfsig]", es_stdout); if (opt.with_colons) es_putc (':', es_stdout); } else if (!opt.fast_list_mode) { p = get_user_id (c->ctrl, sig->keyid, &n, NULL); es_write_sanitized (es_stdout, p, n, opt.with_colons?":":NULL, NULL ); xfree (p); } if (opt.with_colons) es_printf (":%02x%c:", sig->sig_class, sig->flags.exportable?'x':'l'); es_putc ('\n', es_stdout); } else log_error ("invalid node with packet of type %d\n", node->pkt->pkttype); } int proc_packets (ctrl_t ctrl, void *anchor, iobuf_t a ) { int rc; CTX c = xmalloc_clear (sizeof *c); c->ctrl = ctrl; c->anchor = anchor; rc = do_proc_packets (c, a); xfree (c); return rc; } int proc_signature_packets (ctrl_t ctrl, void *anchor, iobuf_t a, strlist_t signedfiles, const char *sigfilename ) { CTX c = xmalloc_clear (sizeof *c); int rc; c->ctrl = ctrl; c->anchor = anchor; c->sigs_only = 1; c->signed_data.data_fd = -1; c->signed_data.data_names = signedfiles; c->signed_data.used = !!signedfiles; c->sigfilename = sigfilename; rc = do_proc_packets (c, a); /* If we have not encountered any signature we print an error messages, send a NODATA status back and return an error code. Using log_error is required because verify_files does not check error codes for each file but we want to terminate the process with an error. */ if (!rc && !c->any.sig_seen) { write_status_text (STATUS_NODATA, "4"); log_error (_("no signature found\n")); rc = GPG_ERR_NO_DATA; } /* Propagate the signature seen flag upward. Do this only on success so that we won't issue the nodata status several times. */ if (!rc && c->anchor && c->any.sig_seen) c->anchor->any.sig_seen = 1; xfree (c); return rc; } int proc_signature_packets_by_fd (ctrl_t ctrl, void *anchor, iobuf_t a, int signed_data_fd ) { int rc; CTX c; c = xtrycalloc (1, sizeof *c); if (!c) return gpg_error_from_syserror (); c->ctrl = ctrl; c->anchor = anchor; c->sigs_only = 1; c->signed_data.data_fd = signed_data_fd; c->signed_data.data_names = NULL; c->signed_data.used = (signed_data_fd != -1); rc = do_proc_packets (c, a); /* If we have not encountered any signature we print an error messages, send a NODATA status back and return an error code. Using log_error is required because verify_files does not check error codes for each file but we want to terminate the process with an error. */ if (!rc && !c->any.sig_seen) { write_status_text (STATUS_NODATA, "4"); log_error (_("no signature found\n")); rc = gpg_error (GPG_ERR_NO_DATA); } /* Propagate the signature seen flag upward. Do this only on success so that we won't issue the nodata status several times. */ if (!rc && c->anchor && c->any.sig_seen) c->anchor->any.sig_seen = 1; xfree ( c ); return rc; } int proc_encryption_packets (ctrl_t ctrl, void *anchor, iobuf_t a ) { CTX c = xmalloc_clear (sizeof *c); int rc; c->ctrl = ctrl; c->anchor = anchor; c->encrypt_only = 1; rc = do_proc_packets (c, a); xfree (c); return rc; } static int check_nesting (CTX c) { int level; for (level=0; c; c = c->anchor) level++; if (level > MAX_NESTING_DEPTH) { log_error ("input data with too deeply nested packets\n"); write_status_text (STATUS_UNEXPECTED, "1"); return GPG_ERR_BAD_DATA; } return 0; } static int do_proc_packets (CTX c, iobuf_t a) { PACKET *pkt; struct parse_packet_ctx_s parsectx; int rc = 0; int any_data = 0; int newpkt; rc = check_nesting (c); if (rc) return rc; pkt = xmalloc( sizeof *pkt ); c->iobuf = a; init_packet(pkt); init_parse_packet (&parsectx, a); while ((rc=parse_packet (&parsectx, pkt)) != -1) { any_data = 1; if (rc) { free_packet (pkt, &parsectx); /* Stop processing when an invalid packet has been encountered * but don't do so when we are doing a --list-packets. */ if (gpg_err_code (rc) == GPG_ERR_INV_PACKET && opt.list_packets == 0) break; continue; } newpkt = -1; if (opt.list_packets) { switch (pkt->pkttype) { case PKT_PUBKEY_ENC: proc_pubkey_enc (c, pkt); break; case PKT_SYMKEY_ENC: proc_symkey_enc (c, pkt); break; case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: case PKT_ENCRYPTED_AEAD:proc_encrypted (c, pkt); break; case PKT_COMPRESSED: rc = proc_compressed (c, pkt); break; default: newpkt = 0; break; } } else if (c->sigs_only) { switch (pkt->pkttype) { case PKT_PUBLIC_KEY: case PKT_SECRET_KEY: case PKT_USER_ID: case PKT_SYMKEY_ENC: case PKT_PUBKEY_ENC: case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: case PKT_ENCRYPTED_AEAD: write_status_text( STATUS_UNEXPECTED, "0" ); rc = GPG_ERR_UNEXPECTED; goto leave; case PKT_SIGNATURE: newpkt = add_signature (c, pkt); break; case PKT_PLAINTEXT: proc_plaintext (c, pkt); break; case PKT_COMPRESSED: rc = proc_compressed (c, pkt); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig (c, pkt); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control (c, pkt); break; default: newpkt = 0; break; } } else if (c->encrypt_only) { switch (pkt->pkttype) { case PKT_PUBLIC_KEY: case PKT_SECRET_KEY: case PKT_USER_ID: write_status_text (STATUS_UNEXPECTED, "0"); rc = GPG_ERR_UNEXPECTED; goto leave; case PKT_SIGNATURE: newpkt = add_signature (c, pkt); break; case PKT_SYMKEY_ENC: proc_symkey_enc (c, pkt); break; case PKT_PUBKEY_ENC: proc_pubkey_enc (c, pkt); break; case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: case PKT_ENCRYPTED_AEAD: proc_encrypted (c, pkt); break; case PKT_PLAINTEXT: proc_plaintext (c, pkt); break; case PKT_COMPRESSED: rc = proc_compressed (c, pkt); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig (c, pkt); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control (c, pkt); break; default: newpkt = 0; break; } } else { switch (pkt->pkttype) { case PKT_PUBLIC_KEY: case PKT_SECRET_KEY: release_list (c); c->list = new_kbnode (pkt); newpkt = 1; break; case PKT_PUBLIC_SUBKEY: case PKT_SECRET_SUBKEY: newpkt = add_subkey (c, pkt); break; case PKT_USER_ID: newpkt = add_user_id (c, pkt); break; case PKT_SIGNATURE: newpkt = add_signature (c, pkt); break; case PKT_PUBKEY_ENC: proc_pubkey_enc (c, pkt); break; case PKT_SYMKEY_ENC: proc_symkey_enc (c, pkt); break; case PKT_ENCRYPTED: case PKT_ENCRYPTED_MDC: case PKT_ENCRYPTED_AEAD: proc_encrypted (c, pkt); break; case PKT_PLAINTEXT: proc_plaintext (c, pkt); break; case PKT_COMPRESSED: rc = proc_compressed (c, pkt); break; case PKT_ONEPASS_SIG: newpkt = add_onepass_sig (c, pkt); break; case PKT_GPG_CONTROL: newpkt = add_gpg_control(c, pkt); break; case PKT_RING_TRUST: newpkt = add_ring_trust (c, pkt); break; default: newpkt = 0; break; } } if (rc) goto leave; /* This is a very ugly construct and frankly, I don't remember why * I used it. Adding the MDC check here is a hack. * The right solution is to initiate another context for encrypted * packet and not to reuse the current one ... It works right * when there is a compression packet between which adds just * an extra layer. * Hmmm: Rewrite this whole module here?? */ if (pkt->pkttype != PKT_SIGNATURE && pkt->pkttype != PKT_MDC) c->any.data = (pkt->pkttype == PKT_PLAINTEXT); if (newpkt == -1) ; else if (newpkt) { pkt = xmalloc (sizeof *pkt); init_packet (pkt); } else free_packet (pkt, &parsectx); } if (rc == GPG_ERR_INV_PACKET) write_status_text (STATUS_NODATA, "3"); if (any_data) rc = 0; else if (rc == -1) write_status_text (STATUS_NODATA, "2"); leave: release_list (c); xfree(c->dek); free_packet (pkt, &parsectx); deinit_parse_packet (&parsectx); xfree (pkt); free_md_filter_context (&c->mfx); return rc; } /* Helper for pka_uri_from_sig to parse the to-be-verified address out of the notation data. */ static pka_info_t * get_pka_address (PKT_signature *sig) { pka_info_t *pka = NULL; struct notation *nd,*notation; notation=sig_to_notation(sig); for(nd=notation;nd;nd=nd->next) { if(strcmp(nd->name,"pka-address@gnupg.org")!=0) continue; /* Not the notation we want. */ /* For now we only use the first valid PKA notation. In future we might want to keep additional PKA notations in a linked list. */ if (is_valid_mailbox (nd->value)) { pka = xmalloc (sizeof *pka + strlen(nd->value)); pka->valid = 0; pka->checked = 0; pka->uri = NULL; strcpy (pka->email, nd->value); break; } } free_notation(notation); return pka; } /* Return the URI from a DNS PKA record. If this record has already be retrieved for the signature we merely return it; if not we go out and try to get that DNS record. */ static const char * pka_uri_from_sig (CTX c, PKT_signature *sig) { if (!sig->flags.pka_tried) { log_assert (!sig->pka_info); sig->flags.pka_tried = 1; sig->pka_info = get_pka_address (sig); if (sig->pka_info) { char *url; unsigned char *fpr; size_t fprlen; if (!gpg_dirmngr_get_pka (c->ctrl, sig->pka_info->email, &fpr, &fprlen, &url)) { if (fpr && fprlen == sizeof sig->pka_info->fpr) { memcpy (sig->pka_info->fpr, fpr, fprlen); if (url) { sig->pka_info->valid = 1; if (!*url) xfree (url); else sig->pka_info->uri = url; url = NULL; } } xfree (fpr); xfree (url); } } } return sig->pka_info? sig->pka_info->uri : NULL; } /* Return true if the AKL has the WKD method specified. */ static int akl_has_wkd_method (void) { struct akl *akl; for (akl = opt.auto_key_locate; akl; akl = akl->next) if (akl->type == AKL_WKD) return 1; return 0; } /* Return the ISSUER fingerprint buffer and its length at R_LEN. * Returns NULL if not available. The returned buffer is valid as * long as SIG is not modified. */ const byte * issuer_fpr_raw (PKT_signature *sig, size_t *r_len) { const byte *p; size_t n; p = parse_sig_subpkt (sig, 1, SIGSUBPKT_ISSUER_FPR, &n); if (p && ((n == 21 && p[0] == 4) || (n == 33 && p[0] == 5))) { *r_len = n - 1; return p+1; } *r_len = 0; return NULL; } /* Return the ISSUER fingerprint string in human readable format if * available. Caller must release the string. */ /* FIXME: Move to another file. */ char * issuer_fpr_string (PKT_signature *sig) { const byte *p; size_t n; p = issuer_fpr_raw (sig, &n); return p? bin2hex (p, n, NULL) : NULL; } static void print_good_bad_signature (int statno, const char *keyid_str, kbnode_t un, PKT_signature *sig, int rc) { char *p; write_status_text_and_buffer (statno, keyid_str, un? un->pkt->pkt.user_id->name:"[?]", un? un->pkt->pkt.user_id->len:3, -1); if (un) p = utf8_to_native (un->pkt->pkt.user_id->name, un->pkt->pkt.user_id->len, 0); else p = xstrdup ("[?]"); if (rc) log_info (_("BAD signature from \"%s\""), p); else if (sig->flags.expired) log_info (_("Expired signature from \"%s\""), p); else log_info (_("Good signature from \"%s\""), p); xfree (p); } static int check_sig_and_print (CTX c, kbnode_t node) { PKT_signature *sig = node->pkt->pkt.signature; const char *astr; int rc; int is_expkey = 0; int is_revkey = 0; char *issuer_fpr = NULL; PKT_public_key *pk = NULL; /* The public key for the signature or NULL. */ const void *extrahash = NULL; size_t extrahashlen = 0; kbnode_t included_keyblock = NULL; if (opt.skip_verify) { log_info(_("signature verification suppressed\n")); return 0; } /* Check that the message composition is valid. * * Per RFC-2440bis (-15) allowed: * * S{1,n} -- detached signature. * S{1,n} P -- old style PGP2 signature * O{1,n} P S{1,n} -- standard OpenPGP signature. * C P S{1,n} -- cleartext signature. * * * O = One-Pass Signature packet. * S = Signature packet. * P = OpenPGP Message packet (Encrypted | Compressed | Literal) * (Note that the current rfc2440bis draft also allows * for a signed message but that does not work as it * introduces ambiguities.) * We keep track of these packages using the marker packet * CTRLPKT_PLAINTEXT_MARK. * C = Marker packet for cleartext signatures. * * We reject all other messages. * * Actually we are calling this too often, i.e. for verification of * each message but better have some duplicate work than to silently * introduce a bug here. */ { kbnode_t n; int n_onepass, n_sig; /* log_debug ("checking signature packet composition\n"); */ /* dump_kbnode (c->list); */ n = c->list; log_assert (n); if ( n->pkt->pkttype == PKT_SIGNATURE ) { /* This is either "S{1,n}" case (detached signature) or "S{1,n} P" (old style PGP2 signature). */ for (n = n->next; n; n = n->next) if (n->pkt->pkttype != PKT_SIGNATURE) break; if (!n) ; /* Okay, this is a detached signature. */ else if (n->pkt->pkttype == PKT_GPG_CONTROL && (n->pkt->pkt.gpg_control->control == CTRLPKT_PLAINTEXT_MARK) ) { if (n->next) goto ambiguous; /* We only allow one P packet. */ extrahash = n->pkt->pkt.gpg_control->data; extrahashlen = n->pkt->pkt.gpg_control->datalen; } else goto ambiguous; } else if (n->pkt->pkttype == PKT_ONEPASS_SIG) { /* This is the "O{1,n} P S{1,n}" case (standard signature). */ for (n_onepass=1, n = n->next; n && n->pkt->pkttype == PKT_ONEPASS_SIG; n = n->next) n_onepass++; if (!n || !(n->pkt->pkttype == PKT_GPG_CONTROL && (n->pkt->pkt.gpg_control->control == CTRLPKT_PLAINTEXT_MARK))) goto ambiguous; extrahash = n->pkt->pkt.gpg_control->data; extrahashlen = n->pkt->pkt.gpg_control->datalen; for (n_sig=0, n = n->next; n && n->pkt->pkttype == PKT_SIGNATURE; n = n->next) n_sig++; if (!n_sig) goto ambiguous; /* If we wanted to disallow multiple sig verification, we'd do * something like this: * * if (n) * goto ambiguous; * * However, this can stay allowable as we can't get here. */ if (n_onepass != n_sig) { log_info ("number of one-pass packets does not match " "number of signature packets\n"); goto ambiguous; } } else if (n->pkt->pkttype == PKT_GPG_CONTROL && n->pkt->pkt.gpg_control->control == CTRLPKT_CLEARSIGN_START ) { /* This is the "C P S{1,n}" case (clear text signature). */ n = n->next; if (!n || !(n->pkt->pkttype == PKT_GPG_CONTROL && (n->pkt->pkt.gpg_control->control == CTRLPKT_PLAINTEXT_MARK))) goto ambiguous; extrahash = n->pkt->pkt.gpg_control->data; extrahashlen = n->pkt->pkt.gpg_control->datalen; for (n_sig=0, n = n->next; n && n->pkt->pkttype == PKT_SIGNATURE; n = n->next) n_sig++; if (n || !n_sig) goto ambiguous; } else { ambiguous: log_error(_("can't handle this ambiguous signature data\n")); return 0; } - } + } /* End checking signature packet composition. */ if (sig->signers_uid) write_status_buffer (STATUS_NEWSIG, sig->signers_uid, strlen (sig->signers_uid), 0); else write_status_text (STATUS_NEWSIG, NULL); astr = openpgp_pk_algo_name ( sig->pubkey_algo ); issuer_fpr = issuer_fpr_string (sig); if (issuer_fpr) { log_info (_("Signature made %s\n"), asctimestamp(sig->timestamp)); log_info (_(" using %s key %s\n"), astr? astr: "?", issuer_fpr); } else if (!keystrlen () || keystrlen () > 8) { log_info (_("Signature made %s\n"), asctimestamp(sig->timestamp)); log_info (_(" using %s key %s\n"), astr? astr: "?", keystr(sig->keyid)); } else /* Legacy format. */ log_info (_("Signature made %s using %s key ID %s\n"), asctimestamp(sig->timestamp), astr? astr: "?", keystr(sig->keyid)); /* In verbose mode print the signers UID. */ if (sig->signers_uid) log_info (_(" issuer \"%s\"\n"), sig->signers_uid); rc = do_check_sig (c, node, extrahash, extrahashlen, NULL, NULL, &is_expkey, &is_revkey, &pk); /* If the key is not found but the signature includes a key block we * use that key block for verification and on success import it. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && sig->flags.key_block && opt.flags.auto_key_import) { PKT_public_key *included_pk; const byte *kblock; size_t kblock_len; included_pk = xcalloc (1, sizeof *included_pk); kblock = parse_sig_subpkt (sig, 1, SIGSUBPKT_KEY_BLOCK, &kblock_len); if (kblock && kblock_len > 1 && !get_pubkey_from_buffer (c->ctrl, included_pk, kblock+1, kblock_len-1, sig->keyid, &included_keyblock)) { rc = do_check_sig (c, node, extrahash, extrahashlen, included_pk, NULL, &is_expkey, &is_revkey, &pk); log_debug ("checked signature using included key block: %s\n", gpg_strerror (rc)); if (!rc) { /* The keyblock has been verified, we now import it. */ rc = import_included_key_block (c->ctrl, included_keyblock); } } free_public_key (included_pk); } /* If the key isn't found, check for a preferred keyserver. Note * that this is only done if honor-keyserver-url has been set. We * test for this in the loop so that we can show info about the * preferred keyservers. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && sig->flags.pref_ks) { const byte *p; int seq = 0; size_t n; int any_pref_ks = 0; while ((p=enum_sig_subpkt (sig, 1, SIGSUBPKT_PREF_KS, &n, &seq, NULL))) { /* According to my favorite copy editor, in English grammar, you say "at" if the key is located on a web page, but "from" if it is located on a keyserver. I'm not going to even try to make two strings here :) */ log_info(_("Key available at: ") ); print_utf8_buffer (log_get_stream(), p, n); log_printf ("\n"); any_pref_ks = 1; if ((opt.keyserver_options.options&KEYSERVER_AUTO_KEY_RETRIEVE) && (opt.keyserver_options.options&KEYSERVER_HONOR_KEYSERVER_URL)) { struct keyserver_spec *spec; spec = parse_preferred_keyserver (sig); if (spec) { int res; if (DBG_LOOKUP) log_debug ("trying auto-key-retrieve method %s\n", "Pref-KS"); free_public_key (pk); pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_keyid (c->ctrl, sig->keyid,spec, 1); glo_ctrl.in_auto_key_retrieve--; if (!res) rc = do_check_sig (c, node, extrahash, extrahashlen, NULL, NULL, &is_expkey, &is_revkey, &pk); else if (DBG_LOOKUP) log_debug ("lookup via %s failed: %s\n", "Pref-KS", gpg_strerror (res)); free_keyserver_spec (spec); if (!rc) break; } } } if (any_pref_ks && (opt.keyserver_options.options&KEYSERVER_AUTO_KEY_RETRIEVE) && !(opt.keyserver_options.options&KEYSERVER_HONOR_KEYSERVER_URL)) log_info (_("Note: Use '%s' to make use of this info\n"), "--keyserver-option honor-keyserver-url"); } /* If the above methods didn't work, our next try is to retrieve the * key from the WKD. This requires that WKD is in the AKL and the * Signer's UID is in the signature. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && (opt.keyserver_options.options & KEYSERVER_AUTO_KEY_RETRIEVE) && !opt.flags.disable_signer_uid && akl_has_wkd_method () && sig->signers_uid) { int res; if (DBG_LOOKUP) log_debug ("trying auto-key-retrieve method %s\n", "WKD"); free_public_key (pk); pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_wkd (c->ctrl, sig->signers_uid, 1, NULL, NULL); glo_ctrl.in_auto_key_retrieve--; /* Fixme: If the fingerprint is embedded in the signature, * compare it to the fingerprint of the returned key. */ if (!res) rc = do_check_sig (c, node, extrahash, extrahashlen, NULL, NULL, &is_expkey, &is_revkey, &pk); else if (DBG_LOOKUP) log_debug ("lookup via %s failed: %s\n", "WKD", gpg_strerror (res)); } /* If the avove methods didn't work, our next try is to use the URI * from a DNS PKA record. This is a legacy method which will * eventually be removed. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && (opt.keyserver_options.options & KEYSERVER_AUTO_KEY_RETRIEVE) && (opt.keyserver_options.options & KEYSERVER_HONOR_PKA_RECORD)) { const char *uri = pka_uri_from_sig (c, sig); if (uri) { /* FIXME: We might want to locate the key using the fingerprint instead of the keyid. */ int res; struct keyserver_spec *spec; spec = parse_keyserver_uri (uri, 1); if (spec) { if (DBG_LOOKUP) log_debug ("trying auto-key-retrieve method %s\n", "PKA"); free_public_key (pk); pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_keyid (c->ctrl, sig->keyid, spec, 1); glo_ctrl.in_auto_key_retrieve--; free_keyserver_spec (spec); if (!res) rc = do_check_sig (c, node, extrahash, extrahashlen, NULL, NULL, &is_expkey, &is_revkey, &pk); else if (DBG_LOOKUP) log_debug ("lookup via %s failed: %s\n", "PKA", gpg_strerror (res)); } } } /* If the above methods didn't work, our next try is to locate * the key via its fingerprint from a keyserver. This requires * that the signers fingerprint is encoded in the signature. */ if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY && (opt.keyserver_options.options&KEYSERVER_AUTO_KEY_RETRIEVE) && keyserver_any_configured (c->ctrl)) { int res; const byte *p; size_t n; p = issuer_fpr_raw (sig, &n); if (p) { if (DBG_LOOKUP) log_debug ("trying auto-key-retrieve method %s\n", "KS"); /* v4 or v5 packet with a SHA-1/256 fingerprint. */ free_public_key (pk); pk = NULL; glo_ctrl.in_auto_key_retrieve++; res = keyserver_import_fprint (c->ctrl, p, n, opt.keyserver, 1); glo_ctrl.in_auto_key_retrieve--; if (!res) rc = do_check_sig (c, node, extrahash, extrahashlen, NULL, NULL, &is_expkey, &is_revkey, &pk); else if (DBG_LOOKUP) log_debug ("lookup via %s failed: %s\n", "KS", gpg_strerror (res)); } } if (!rc || gpg_err_code (rc) == GPG_ERR_BAD_SIGNATURE) { kbnode_t un, keyblock; int count = 0; int statno; char keyid_str[50]; PKT_public_key *mainpk = NULL; if (rc) statno = STATUS_BADSIG; else if (sig->flags.expired) statno = STATUS_EXPSIG; else if (is_expkey) statno = STATUS_EXPKEYSIG; else if(is_revkey) statno = STATUS_REVKEYSIG; else statno = STATUS_GOODSIG; /* FIXME: We should have the public key in PK and thus the * keyblock has already been fetched. Thus we could use the * fingerprint or PK itself to lookup the entire keyblock. That * would best be done with a cache. */ if (included_keyblock) { keyblock = included_keyblock; included_keyblock = NULL; } else keyblock = get_pubkeyblock_for_sig (c->ctrl, sig); snprintf (keyid_str, sizeof keyid_str, "%08lX%08lX [uncertain] ", (ulong)sig->keyid[0], (ulong)sig->keyid[1]); /* Find and print the primary user ID along with the "Good|Expired|Bad signature" line. */ for (un=keyblock; un; un = un->next) { int valid; if (un->pkt->pkttype==PKT_PUBLIC_KEY) { mainpk = un->pkt->pkt.public_key; continue; } if (un->pkt->pkttype != PKT_USER_ID) continue; if (!un->pkt->pkt.user_id->created) continue; if (un->pkt->pkt.user_id->flags.revoked) continue; if (un->pkt->pkt.user_id->flags.expired) continue; if (!un->pkt->pkt.user_id->flags.primary) continue; /* We want the textual primary user ID here */ if (un->pkt->pkt.user_id->attrib_data) continue; log_assert (mainpk); /* Since this is just informational, don't actually ask the user to update any trust information. (Note: we register the signature later.) Because print_good_bad_signature does not print a LF we need to compute the validity before calling that function. */ if ((opt.verify_options & VERIFY_SHOW_UID_VALIDITY)) valid = get_validity (c->ctrl, keyblock, mainpk, un->pkt->pkt.user_id, NULL, 0); else valid = 0; /* Not used. */ keyid_str[17] = 0; /* cut off the "[uncertain]" part */ print_good_bad_signature (statno, keyid_str, un, sig, rc); if ((opt.verify_options & VERIFY_SHOW_UID_VALIDITY)) log_printf (" [%s]\n",trust_value_to_string(valid)); else log_printf ("\n"); count++; } log_assert (mainpk); /* In case we did not found a valid textual userid above we print the first user id packet or a "[?]" instead along with the "Good|Expired|Bad signature" line. */ if (!count) { /* Try for an invalid textual userid */ for (un=keyblock; un; un = un->next) { if (un->pkt->pkttype == PKT_USER_ID && !un->pkt->pkt.user_id->attrib_data) break; } /* Try for any userid at all */ if (!un) { for (un=keyblock; un; un = un->next) { if (un->pkt->pkttype == PKT_USER_ID) break; } } if (opt.trust_model==TM_ALWAYS || !un) keyid_str[17] = 0; /* cut off the "[uncertain]" part */ print_good_bad_signature (statno, keyid_str, un, sig, rc); if (opt.trust_model != TM_ALWAYS && un) log_printf (" %s",_("[uncertain]") ); log_printf ("\n"); } /* If we have a good signature and already printed * the primary user ID, print all the other user IDs */ if (count && !rc && !(opt.verify_options & VERIFY_SHOW_PRIMARY_UID_ONLY)) { char *p; for( un=keyblock; un; un = un->next) { if (un->pkt->pkttype != PKT_USER_ID) continue; if ((un->pkt->pkt.user_id->flags.revoked || un->pkt->pkt.user_id->flags.expired) && !(opt.verify_options & VERIFY_SHOW_UNUSABLE_UIDS)) continue; /* Skip textual primary user ids which we printed above. */ if (un->pkt->pkt.user_id->flags.primary && !un->pkt->pkt.user_id->attrib_data ) continue; /* If this user id has attribute data, print that. */ if (un->pkt->pkt.user_id->attrib_data) { dump_attribs (un->pkt->pkt.user_id, mainpk); if (opt.verify_options&VERIFY_SHOW_PHOTOS) show_photos (c->ctrl, un->pkt->pkt.user_id->attribs, un->pkt->pkt.user_id->numattribs, mainpk ,un->pkt->pkt.user_id); } p = utf8_to_native (un->pkt->pkt.user_id->name, un->pkt->pkt.user_id->len, 0); log_info (_(" aka \"%s\""), p); xfree (p); if ((opt.verify_options & VERIFY_SHOW_UID_VALIDITY)) { const char *valid; if (un->pkt->pkt.user_id->flags.revoked) valid = _("revoked"); else if (un->pkt->pkt.user_id->flags.expired) valid = _("expired"); else /* Since this is just informational, don't actually ask the user to update any trust information. */ valid = (trust_value_to_string (get_validity (c->ctrl, keyblock, mainpk, un->pkt->pkt.user_id, NULL, 0))); log_printf (" [%s]\n",valid); } else log_printf ("\n"); } } /* For good signatures print notation data. */ if (!rc) { if ((opt.verify_options & VERIFY_SHOW_POLICY_URLS)) show_policy_url (sig, 0, 1); else show_policy_url (sig, 0, 2); if ((opt.verify_options & VERIFY_SHOW_KEYSERVER_URLS)) show_keyserver_url (sig, 0, 1); else show_keyserver_url (sig, 0, 2); if ((opt.verify_options & VERIFY_SHOW_NOTATIONS)) show_notation (sig, 0, 1, (((opt.verify_options&VERIFY_SHOW_STD_NOTATIONS)?1:0) + ((opt.verify_options&VERIFY_SHOW_USER_NOTATIONS)?2:0))); else show_notation (sig, 0, 2, 0); } /* For good signatures print the VALIDSIG status line. */ if (!rc && is_status_enabled () && pk) { char pkhex[MAX_FINGERPRINT_LEN*2+1]; char mainpkhex[MAX_FINGERPRINT_LEN*2+1]; hexfingerprint (pk, pkhex, sizeof pkhex); hexfingerprint (mainpk, mainpkhex, sizeof mainpkhex); /* TODO: Replace the reserved '0' in the field below with bits for status flags (policy url, notation, etc.). */ write_status_printf (STATUS_VALIDSIG, "%s %s %lu %lu %d 0 %d %d %02X %s", pkhex, strtimestamp (sig->timestamp), (ulong)sig->timestamp, (ulong)sig->expiredate, sig->version, sig->pubkey_algo, sig->digest_algo, sig->sig_class, mainpkhex); } /* Print compliance warning for Good signatures. */ if (!rc && pk && !opt.quiet && !gnupg_pk_is_compliant (opt.compliance, pk->pubkey_algo, pk->pkey, nbits_from_pk (pk), NULL)) { log_info (_("WARNING: This key is not suitable for signing" " in %s mode\n"), gnupg_compliance_option_string (opt.compliance)); } /* For good signatures compute and print the trust information. Note that in the Tofu trust model this may ask the user on how to resolve a conflict. */ if (!rc) { if ((opt.verify_options & VERIFY_PKA_LOOKUPS)) pka_uri_from_sig (c, sig); /* Make sure PKA info is available. */ rc = check_signatures_trust (c->ctrl, sig); } /* Print extra information about the signature. */ if (sig->flags.expired) { log_info (_("Signature expired %s\n"), asctimestamp(sig->expiredate)); rc = GPG_ERR_GENERAL; /* Need a better error here? */ } else if (sig->expiredate) log_info (_("Signature expires %s\n"), asctimestamp(sig->expiredate)); if (opt.verbose) { char pkstrbuf[PUBKEY_STRING_SIZE]; if (pk) pubkey_string (pk, pkstrbuf, sizeof pkstrbuf); else *pkstrbuf = 0; log_info (_("%s signature, digest algorithm %s%s%s\n"), sig->sig_class==0x00?_("binary"): sig->sig_class==0x01?_("textmode"):_("unknown"), gcry_md_algo_name (sig->digest_algo), *pkstrbuf?_(", key algorithm "):"", pkstrbuf); } /* Print final warnings. */ if (!rc && !c->signed_data.used) { /* Signature is basically good but we test whether the deprecated command gpg --verify FILE.sig was used instead of gpg --verify FILE.sig FILE to verify a detached signature. If we figure out that a data file with a matching name exists, we print a warning. The problem is that the first form would also verify a standard signature. This behavior could be used to create a made up .sig file for a tarball by creating a standard signature from a valid detached signature packet (for example from a signed git tag). Then replace the sig file on the FTP server along with a changed tarball. Using the first form the verify command would correctly verify the signature but don't even consider the tarball. */ kbnode_t n; char *dfile; dfile = get_matching_datafile (c->sigfilename); if (dfile) { for (n = c->list; n; n = n->next) if (n->pkt->pkttype != PKT_SIGNATURE) break; if (n) { /* Not only signature packets in the tree thus this is not a detached signature. */ log_info (_("WARNING: not a detached signature; " "file '%s' was NOT verified!\n"), dfile); } xfree (dfile); } } /* Compute compliance with CO_DE_VS. */ if (pk && is_status_enabled () && gnupg_pk_is_compliant (CO_DE_VS, pk->pubkey_algo, pk->pkey, nbits_from_pk (pk), NULL) && gnupg_digest_is_compliant (CO_DE_VS, sig->digest_algo)) write_status_strings (STATUS_VERIFICATION_COMPLIANCE_MODE, gnupg_status_compliance_flag (CO_DE_VS), NULL); free_public_key (pk); pk = NULL; release_kbnode( keyblock ); if (rc) g10_errors_seen = 1; if (opt.batch && rc) g10_exit (1); } else { write_status_printf (STATUS_ERRSIG, "%08lX%08lX %d %d %02x %lu %d %s", (ulong)sig->keyid[0], (ulong)sig->keyid[1], sig->pubkey_algo, sig->digest_algo, sig->sig_class, (ulong)sig->timestamp, gpg_err_code (rc), issuer_fpr? issuer_fpr:"-"); if (gpg_err_code (rc) == GPG_ERR_NO_PUBKEY) { write_status_printf (STATUS_NO_PUBKEY, "%08lX%08lX", (ulong)sig->keyid[0], (ulong)sig->keyid[1]); } if (gpg_err_code (rc) != GPG_ERR_NOT_PROCESSED) log_error (_("Can't check signature: %s\n"), gpg_strerror (rc)); } free_public_key (pk); release_kbnode (included_keyblock); xfree (issuer_fpr); return rc; } /* * Process the tree which starts at node */ static void proc_tree (CTX c, kbnode_t node) { kbnode_t n1; int rc; if (opt.list_packets || opt.list_only) return; /* We must skip our special plaintext marker packets here because they may be the root packet. These packets are only used in additional checks and skipping them here doesn't matter. */ while (node && node->pkt->pkttype == PKT_GPG_CONTROL && node->pkt->pkt.gpg_control->control == CTRLPKT_PLAINTEXT_MARK) { node = node->next; } if (!node) return; c->trustletter = ' '; if (node->pkt->pkttype == PKT_PUBLIC_KEY || node->pkt->pkttype == PKT_PUBLIC_SUBKEY) { merge_keys_and_selfsig (c->ctrl, node); list_node (c, node); } else if (node->pkt->pkttype == PKT_SECRET_KEY) { merge_keys_and_selfsig (c->ctrl, node); list_node (c, node); } else if (node->pkt->pkttype == PKT_ONEPASS_SIG) { /* Check all signatures. */ if (!c->any.data) { int use_textmode = 0; free_md_filter_context (&c->mfx); /* Prepare to create all requested message digests. */ rc = gcry_md_open (&c->mfx.md, 0, 0); if (rc) goto hash_err; /* Fixme: why looking for the signature packet and not the one-pass packet? */ for (n1 = node; (n1 = find_next_kbnode (n1, PKT_SIGNATURE));) gcry_md_enable (c->mfx.md, n1->pkt->pkt.signature->digest_algo); if (n1 && n1->pkt->pkt.onepass_sig->sig_class == 0x01) use_textmode = 1; /* Ask for file and hash it. */ if (c->sigs_only) { if (c->signed_data.used && c->signed_data.data_fd != -1) rc = hash_datafile_by_fd (c->mfx.md, NULL, c->signed_data.data_fd, use_textmode); else rc = hash_datafiles (c->mfx.md, NULL, c->signed_data.data_names, c->sigfilename, use_textmode); } else { rc = ask_for_detached_datafile (c->mfx.md, c->mfx.md2, iobuf_get_real_fname (c->iobuf), use_textmode); } hash_err: if (rc) { log_error ("can't hash datafile: %s\n", gpg_strerror (rc)); return; } } else if (c->signed_data.used) { log_error (_("not a detached signature\n")); return; } for (n1 = node; (n1 = find_next_kbnode (n1, PKT_SIGNATURE));) check_sig_and_print (c, n1); } else if (node->pkt->pkttype == PKT_GPG_CONTROL && node->pkt->pkt.gpg_control->control == CTRLPKT_CLEARSIGN_START) { /* Clear text signed message. */ if (!c->any.data) { log_error ("cleartext signature without data\n"); return; } else if (c->signed_data.used) { log_error (_("not a detached signature\n")); return; } for (n1 = node; (n1 = find_next_kbnode (n1, PKT_SIGNATURE));) check_sig_and_print (c, n1); } else if (node->pkt->pkttype == PKT_SIGNATURE) { PKT_signature *sig = node->pkt->pkt.signature; int multiple_ok = 1; n1 = find_next_kbnode (node, PKT_SIGNATURE); if (n1) { byte class = sig->sig_class; byte hash = sig->digest_algo; for (; n1; (n1 = find_next_kbnode(n1, PKT_SIGNATURE))) { /* We can't currently handle multiple signatures of * different classes (we'd pretty much have to run a * different hash context for each), but if they are all * the same and it is detached signature, we make an * exception. Note that the old code also disallowed * multiple signatures if the digest algorithms are * different. We softened this restriction only for * detached signatures, to be on the safe side. */ if (n1->pkt->pkt.signature->sig_class != class || (c->any.data && n1->pkt->pkt.signature->digest_algo != hash)) { multiple_ok = 0; log_info (_("WARNING: multiple signatures detected. " "Only the first will be checked.\n")); break; } } } if (sig->sig_class != 0x00 && sig->sig_class != 0x01) { log_info(_("standalone signature of class 0x%02x\n"), sig->sig_class); } else if (!c->any.data) { /* Detached signature */ free_md_filter_context (&c->mfx); rc = gcry_md_open (&c->mfx.md, sig->digest_algo, 0); if (rc) goto detached_hash_err; if (multiple_ok) { /* If we have and want to handle multiple signatures we * need to enable all hash algorithms for the context. */ for (n1 = node; (n1 = find_next_kbnode (n1, PKT_SIGNATURE)); ) if (!openpgp_md_test_algo (n1->pkt->pkt.signature->digest_algo)) gcry_md_enable (c->mfx.md, map_md_openpgp_to_gcry (n1->pkt->pkt.signature->digest_algo)); } if (RFC2440 || RFC4880) ; /* Strict RFC mode. */ else if (sig->digest_algo == DIGEST_ALGO_SHA1 && sig->pubkey_algo == PUBKEY_ALGO_DSA && sig->sig_class == 0x01) { /* Enable a workaround for a pgp5 bug when the detached * signature has been created in textmode. Note that we * do not implement this for multiple signatures with * different hash algorithms. */ rc = gcry_md_open (&c->mfx.md2, sig->digest_algo, 0); if (rc) goto detached_hash_err; } /* Here we used to have another hack to work around a pgp * 2 bug: It worked by not using the textmode for detached * signatures; this would let the first signature check * (on md) fail but the second one (on md2), which adds an * extra CR would then have produced the "correct" hash. * This is very, very ugly hack but it may haved help in * some cases (and break others). * c->mfx.md2? 0 :(sig->sig_class == 0x01) */ if (DBG_HASHING) { gcry_md_debug (c->mfx.md, "verify"); if (c->mfx.md2) gcry_md_debug (c->mfx.md2, "verify2"); } if (c->sigs_only) { if (c->signed_data.used && c->signed_data.data_fd != -1) rc = hash_datafile_by_fd (c->mfx.md, c->mfx.md2, c->signed_data.data_fd, (sig->sig_class == 0x01)); else rc = hash_datafiles (c->mfx.md, c->mfx.md2, c->signed_data.data_names, c->sigfilename, (sig->sig_class == 0x01)); } else { rc = ask_for_detached_datafile (c->mfx.md, c->mfx.md2, iobuf_get_real_fname(c->iobuf), (sig->sig_class == 0x01)); } detached_hash_err: if (rc) { log_error ("can't hash datafile: %s\n", gpg_strerror (rc)); return; } } else if (c->signed_data.used) { log_error (_("not a detached signature\n")); return; } else if (!opt.quiet) log_info (_("old style (PGP 2.x) signature\n")); if (multiple_ok) { for (n1 = node; n1; (n1 = find_next_kbnode(n1, PKT_SIGNATURE))) check_sig_and_print (c, n1); } else check_sig_and_print (c, node); } else { dump_kbnode (c->list); log_error ("invalid root packet detected in proc_tree()\n"); dump_kbnode (node); } } diff --git a/g10/packet.h b/g10/packet.h index 5c0de577c..eec3050e9 100644 --- a/g10/packet.h +++ b/g10/packet.h @@ -1,963 +1,966 @@ /* packet.h - OpenPGP packet definitions * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, * 2007 Free Software Foundation, Inc. * Copyright (C) 2015 g10 Code GmbH * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #ifndef G10_PACKET_H #define G10_PACKET_H #include "../common/types.h" #include "../common/iobuf.h" #include "../common/strlist.h" #include "dek.h" #include "filter.h" #include "../common/openpgpdefs.h" #include "../common/userids.h" #include "../common/util.h" #define DEBUG_PARSE_PACKET 1 /* Maximum length of packets to avoid excessive memory allocation. */ #define MAX_KEY_PACKET_LENGTH (256 * 1024) #define MAX_UID_PACKET_LENGTH ( 2 * 1024) #define MAX_COMMENT_PACKET_LENGTH ( 64 * 1024) #define MAX_ATTR_PACKET_LENGTH ( 16 * 1024*1024) /* Constants to allocate static MPI arrays. */ #define PUBKEY_MAX_NPKEY OPENPGP_MAX_NPKEY #define PUBKEY_MAX_NSKEY OPENPGP_MAX_NSKEY #define PUBKEY_MAX_NSIG OPENPGP_MAX_NSIG #define PUBKEY_MAX_NENC OPENPGP_MAX_NENC /* Usage flags */ #define PUBKEY_USAGE_SIG GCRY_PK_USAGE_SIGN /* Good for signatures. */ #define PUBKEY_USAGE_ENC GCRY_PK_USAGE_ENCR /* Good for encryption. */ #define PUBKEY_USAGE_CERT GCRY_PK_USAGE_CERT /* Also good to certify keys.*/ #define PUBKEY_USAGE_AUTH GCRY_PK_USAGE_AUTH /* Good for authentication. */ #define PUBKEY_USAGE_UNKNOWN GCRY_PK_USAGE_UNKN /* Unknown usage flag. */ #define PUBKEY_USAGE_NONE 256 /* No usage given. */ #if (GCRY_PK_USAGE_SIGN | GCRY_PK_USAGE_ENCR | GCRY_PK_USAGE_CERT \ | GCRY_PK_USAGE_AUTH | GCRY_PK_USAGE_UNKN) >= 256 # error Please choose another value for PUBKEY_USAGE_NONE #endif /* Helper macros. */ #define is_RSA(a) ((a)==PUBKEY_ALGO_RSA || (a)==PUBKEY_ALGO_RSA_E \ || (a)==PUBKEY_ALGO_RSA_S ) #define is_ELGAMAL(a) ((a)==PUBKEY_ALGO_ELGAMAL_E) #define is_DSA(a) ((a)==PUBKEY_ALGO_DSA) /* A pointer to the packet object. */ typedef struct packet_struct PACKET; /* PKT_GPG_CONTROL types */ typedef enum { CTRLPKT_CLEARSIGN_START = 1, CTRLPKT_PIPEMODE = 2, CTRLPKT_PLAINTEXT_MARK =3 } ctrlpkttype_t; typedef enum { PREFTYPE_NONE = 0, PREFTYPE_SYM = 1, PREFTYPE_HASH = 2, PREFTYPE_ZIP = 3, PREFTYPE_AEAD = 4 } preftype_t; typedef struct { byte type; byte value; } prefitem_t; /* A string-to-key specifier as defined in RFC 4880, Section 3.7. */ typedef struct { int mode; /* Must be an integer due to the GNU modes 1001 et al. */ byte hash_algo; byte salt[8]; /* The *coded* (i.e., the serialized version) iteration count. */ u32 count; } STRING2KEY; /* A symmetric-key encrypted session key packet as defined in RFC 4880, Section 5.3. All fields are serialized. */ typedef struct { /* We support version 4 (rfc4880) and 5 (rfc4880bis). */ byte version; /* The cipher algorithm used to encrypt the session key. Note that * this may be different from the algorithm that is used to encrypt * bulk data. */ byte cipher_algo; /* The AEAD algorithm or 0 for CFB encryption. */ byte aead_algo; /* The string-to-key specifier. */ STRING2KEY s2k; /* The length of SESKEY in bytes or 0 if this packet does not encrypt a session key. (In the latter case, the results of the S2K function on the password is the session key. See RFC 4880, Section 5.3.) */ byte seskeylen; /* The session key as encrypted by the S2K specifier. For AEAD this * includes the nonce and the authentication tag. */ byte seskey[1]; } PKT_symkey_enc; /* A public-key encrypted session key packet as defined in RFC 4880, Section 5.1. All fields are serialized. */ typedef struct { /* The 64-bit keyid. */ u32 keyid[2]; /* The packet's version. Currently, only version 3 is defined. */ byte version; /* The algorithm used for the public key encryption scheme. */ byte pubkey_algo; /* Whether to hide the key id. This value is not directly serialized. */ byte throw_keyid; /* The session key. */ gcry_mpi_t data[PUBKEY_MAX_NENC]; } PKT_pubkey_enc; /* An object to build a list of public-key encrypted session key. */ struct pubkey_enc_list { struct pubkey_enc_list *next; u32 keyid[2]; int pubkey_algo; int result; gcry_mpi_t data[PUBKEY_MAX_NENC]; }; /* A one-pass signature packet as defined in RFC 4880, Section 5.4. All fields are serialized. */ typedef struct { u32 keyid[2]; /* The 64-bit keyid */ /* The signature's classification (RFC 4880, Section 5.2.1). */ byte sig_class; byte digest_algo; /* algorithm used for digest */ byte pubkey_algo; /* algorithm used for public key scheme */ /* A message can be signed by multiple keys. In this case, there are n one-pass signature packets before the message to sign and n signatures packets after the message. It is conceivable that someone wants to not only sign the message, but all of the signatures. Now we need to distinguish between signing the message and signing the message plus the surrounding signatures. This is the point of this flag. If set, it means: I sign all of the data starting at the next packet. */ byte last; } PKT_onepass_sig; /* A v4 OpenPGP signature has a hashed and unhashed area containing co-called signature subpackets (RFC 4880, Section 5.2.3). These areas are described by this data structure. Use enum_sig_subpkt to parse this area. */ typedef struct { size_t size; /* allocated */ size_t len; /* used (serialized) */ byte data[1]; /* the serialized subpackes (serialized) */ } subpktarea_t; /* The in-memory representation of a designated revoker signature subpacket (RFC 4880, Section 5.2.3.15). */ struct revocation_key { /* A bit field. 0x80 must be set. 0x40 means this information is sensitive (and should not be uploaded to a keyserver by default). */ byte class; /* The public-key algorithm ID. */ byte algid; /* The length of the fingerprint. */ byte fprlen; /* The fingerprint of the authorized key. */ byte fpr[MAX_FINGERPRINT_LEN]; }; /* Object to keep information about a PKA DNS record. */ typedef struct { int valid; /* An actual PKA record exists for EMAIL. */ int checked; /* Set to true if the FPR has been checked against the actual key. */ char *uri; /* Malloced string with the URI. NULL if the URI is not available.*/ unsigned char fpr[20]; /* The fingerprint as stored in the PKA RR. */ char email[1];/* The email address from the notation data. */ } pka_info_t; /* A signature packet (RFC 4880, Section 5.2). Only a subset of these fields are directly serialized (these are marked as such); the rest are read from the subpackets, which are not synthesized when serializing this data structure (i.e., when using build_packet()). Instead, the subpackets must be created by hand. */ typedef struct { struct { unsigned checked:1; /* Signature has been checked. */ unsigned valid:1; /* Signature is good (if checked is set). */ unsigned chosen_selfsig:1; /* A selfsig that is the chosen one. */ unsigned unknown_critical:1; unsigned exportable:1; unsigned revocable:1; unsigned policy_url:1; /* At least one policy URL is present */ unsigned notation:1; /* At least one notation is present */ unsigned pref_ks:1; /* At least one preferred keyserver is present */ unsigned key_block:1; /* A key block subpacket is present. */ unsigned expired:1; unsigned pka_tried:1; /* Set if we tried to retrieve the PKA record. */ } flags; /* The key that allegedly generated this signature. (Directly serialized in v3 sigs; for v4 sigs, this must be explicitly added as an issuer subpacket (5.2.3.5.) */ u32 keyid[2]; /* When the signature was made (seconds since the Epoch). (Directly serialized in v3 sigs; for v4 sigs, this must be explicitly added as a signature creation time subpacket (5.2.3.4).) */ u32 timestamp; u32 expiredate; /* Expires at this date or 0 if not at all. */ /* The serialization format used / to use. If 0, then defaults to version 3. (Serialized.) */ byte version; /* The signature type. (See RFC 4880, Section 5.2.1.) */ byte sig_class; /* Algorithm used for public key scheme (e.g., PUBKEY_ALGO_RSA). (Serialized.) */ byte pubkey_algo; /* Algorithm used for digest (e.g., DIGEST_ALGO_SHA1). (Serialized.) */ byte digest_algo; byte trust_depth; byte trust_value; const byte *trust_regexp; struct revocation_key *revkey; int numrevkeys; int help_counter; /* Used internally bu some functions. */ pka_info_t *pka_info; /* Malloced PKA data or NULL if not available. See also flags.pka_tried. */ char *signers_uid; /* Malloced value of the SIGNERS_UID * subpacket or NULL. This string has * already been sanitized. */ subpktarea_t *hashed; /* All subpackets with hashed data (v4 only). */ subpktarea_t *unhashed; /* Ditto for unhashed data. */ /* First 2 bytes of the digest. (Serialized. Note: this is not automatically filled in when serializing a signature!) */ byte digest_start[2]; /* The signature. (Serialized.) */ gcry_mpi_t data[PUBKEY_MAX_NSIG]; /* The message digest and its length (in bytes). Note the maximum digest length is 512 bits (64 bytes). If DIGEST_LEN is 0, then the digest's value has not been saved here. */ byte digest[512 / 8]; int digest_len; } PKT_signature; #define ATTRIB_IMAGE 1 /* This is the cooked form of attributes. */ struct user_attribute { byte type; const byte *data; u32 len; }; /* A user id (RFC 4880, Section 5.11) or a user attribute packet (RFC 4880, Section 5.12). Only a subset of these fields are directly serialized (these are marked as such); the rest are read from the self-signatures in merge_keys_and_selfsig()). */ typedef struct { int ref; /* reference counter */ /* The length of NAME. */ int len; struct user_attribute *attribs; int numattribs; /* If this is not NULL, the packet is a user attribute rather than a user id (See RFC 4880 5.12). (Serialized.) */ byte *attrib_data; /* The length of ATTRIB_DATA. */ unsigned long attrib_len; byte *namehash; int help_key_usage; u32 help_key_expire; int help_full_count; int help_marginal_count; u32 expiredate; /* expires at this date or 0 if not at all */ prefitem_t *prefs; /* list of preferences (may be NULL)*/ u32 created; /* according to the self-signature */ u32 keyupdate; /* From the ring trust packet. */ char *updateurl; /* NULL or the URL of the last update origin. */ byte keyorg; /* From the ring trust packet. */ byte selfsigversion; struct { unsigned int mdc:1; unsigned int aead:1; unsigned int ks_modify:1; unsigned int compacted:1; unsigned int primary:2; /* 2 if set via the primary flag, 1 if calculated */ + /* Note that this flag is set in a + * keyblock at max for one User ID and for + * one User Attribute per keyblock. */ unsigned int revoked:1; unsigned int expired:1; } flags; char *mbox; /* NULL or the result of mailbox_from_userid. */ /* The text contained in the user id packet, which is normally the * name and email address of the key holder (See RFC 4880 5.11). * (Serialized.). For convenience an extra Nul is always appended. */ char name[1]; } PKT_user_id; struct revoke_info { /* revoked at this date */ u32 date; /* the keyid of the revoking key (selfsig or designated revoker) */ u32 keyid[2]; /* the algo of the revoking key */ byte algo; }; /* Information pertaining to secret keys. */ struct seckey_info { int is_protected:1; /* The secret info is protected and must */ /* be decrypted before use, the protected */ /* MPIs are simply (void*) pointers to memory */ /* and should never be passed to a mpi_xxx() */ int sha1chk:1; /* SHA1 is used instead of a 16 bit checksum */ u16 csum; /* Checksum for old protection modes. */ byte algo; /* Cipher used to protect the secret information. */ STRING2KEY s2k; /* S2K parameter. */ byte ivlen; /* Used length of the IV. */ byte iv[16]; /* Initialization vector for CFB mode. */ }; /**************** * The in-memory representation of a public key (RFC 4880, Section * 5.5). Note: this structure contains significantly more information * than is contained in an OpenPGP public key packet. This * information is derived from the self-signed signatures (by * merge_keys_and_selfsig()) and is ignored when serializing the * packet. The fields that are actually written out when serializing * this packet are marked as accordingly. * * We assume that secret keys have the same number of parameters as * the public key and that the public parameters are the first items * in the PKEY array. Thus NPKEY is always less than NSKEY and it is * possible to compare the secret and public keys by comparing the * first NPKEY elements of the PKEY array. Note that since GnuPG 2.1 * we don't use secret keys anymore directly because they are managed * by gpg-agent. However for parsing OpenPGP key files we need a way * to temporary store those secret keys. We do this by putting them * into the public key structure and extending the PKEY field to NSKEY * elements; the extra secret key information are stored in the * SECKEY_INFO field. */ typedef struct { /* When the key was created. (Serialized.) */ u32 timestamp; u32 expiredate; /* expires at this date or 0 if not at all */ u32 max_expiredate; /* must not expire past this date */ struct revoke_info revoked; /* An OpenPGP packet consists of a header and a body. This is the size of the header. If this is 0, an appropriate size is automatically chosen based on the size of the body. (Serialized.) */ byte hdrbytes; /* The serialization format. If 0, the default version (4) is used when serializing. (Serialized.) */ byte version; byte selfsigversion; /* highest version of all of the self-sigs */ /* The public key algorithm. (Serialized.) */ byte pubkey_algo; byte pubkey_usage; /* for now only used to pass it to getkey() */ byte req_usage; /* hack to pass a request to getkey() */ byte fprlen; /* 0 or length of FPR. */ u32 has_expired; /* set to the expiration date if expired */ /* keyid of the primary key. Never access this value directly. Instead, use pk_main_keyid(). */ u32 main_keyid[2]; /* keyid of this key. Never access this value directly! Instead, use pk_keyid(). */ u32 keyid[2]; /* Fingerprint of the key. Only valid if FPRLEN is not 0. */ byte fpr[MAX_FINGERPRINT_LEN]; prefitem_t *prefs; /* list of preferences (may be NULL) */ struct { unsigned int mdc:1; /* MDC feature set. */ unsigned int aead:1; /* AEAD feature set. */ unsigned int disabled_valid:1;/* The next flag is valid. */ unsigned int disabled:1; /* The key has been disabled. */ unsigned int primary:1; /* This is a primary key. */ unsigned int revoked:2; /* Key has been revoked. 1 = revoked by the owner 2 = revoked by designated revoker. */ unsigned int maybe_revoked:1; /* A designated revocation is present, but without the key to check it. */ unsigned int valid:1; /* Key (especially subkey) is valid. */ unsigned int dont_cache:1; /* Do not cache this key. */ unsigned int backsig:2; /* 0=none, 1=bad, 2=good. */ unsigned int serialno_valid:1;/* SERIALNO below is valid. */ unsigned int exact:1; /* Found via exact (!) search. */ } flags; PKT_user_id *user_id; /* If != NULL: found by that uid. */ struct revocation_key *revkey; int numrevkeys; u32 trust_timestamp; byte trust_depth; byte trust_value; byte keyorg; /* From the ring trust packet. */ u32 keyupdate; /* From the ring trust packet. */ char *updateurl; /* NULL or the URL of the last update origin. */ const byte *trust_regexp; char *serialno; /* Malloced hex string or NULL if it is likely not on a card. See also flags.serialno_valid. */ /* If not NULL this malloced structure describes a secret key. (Serialized.) */ struct seckey_info *seckey_info; /* The public key. Contains pubkey_get_npkey (pubkey_algo) + pubkey_get_nskey (pubkey_algo) MPIs. (If pubkey_get_npkey returns 0, then the algorithm is not understood and the PKEY contains a single opaque MPI.) (Serialized.) */ gcry_mpi_t pkey[PUBKEY_MAX_NSKEY]; /* Right, NSKEY elements. */ } PKT_public_key; /* Evaluates as true if the pk is disabled, and false if it isn't. If there is no disable value cached, fill one in. */ #define pk_is_disabled(a) \ (((a)->flags.disabled_valid)? \ ((a)->flags.disabled):(cache_disabled_value(ctrl,(a)))) typedef struct { int len; /* length of data */ char data[1]; } PKT_comment; /* A compression packet (RFC 4880, Section 5.6). */ typedef struct { /* Not used. */ u32 len; /* Whether the serialized version of the packet used / should use the new format. */ byte new_ctb; /* The compression algorithm. */ byte algorithm; /* An iobuf holding the data to be decompressed. (This is not used for compression!) */ iobuf_t buf; } PKT_compressed; /* A symmetrically encrypted data packet (RFC 4880, Section 5.7) or a symmetrically encrypted integrity protected data packet (Section 5.13) */ typedef struct { /* Remaining length of encrypted data. */ u32 len; /* When encrypting in CFB mode, the first block size bytes of data * are random data and the following 2 bytes are copies of the last * two bytes of the random data (RFC 4880, Section 5.7). This * provides a simple check that the key is correct. EXTRALEN is the * size of this extra data or, in AEAD mode, the length of the * headers and the tags. This is used by build_packet when writing * out the packet's header. */ int extralen; /* Whether the serialized version of the packet used / should use the new format. */ byte new_ctb; /* Whether the packet has an indeterminate length (old format) or was encoded using partial body length headers (new format). Note: this is ignored when encrypting. */ byte is_partial; /* If 0, MDC is disabled. Otherwise, the MDC method that was used (only DIGEST_ALGO_SHA1 has ever been defined). */ byte mdc_method; /* If 0, AEAD is not used. Otherwise, the used AEAD algorithm. * MDC_METHOD (above) shall be zero if AEAD is used. */ byte aead_algo; /* The cipher algo for/from the AEAD packet. 0 for other encryption * packets. */ byte cipher_algo; /* The chunk byte from the AEAD packet. */ byte chunkbyte; /* An iobuf holding the data to be decrypted. (This is not used for encryption!) */ iobuf_t buf; } PKT_encrypted; typedef struct { byte hash[20]; } PKT_mdc; /* Subtypes for the ring trust packet. */ #define RING_TRUST_SIG 0 /* The classical signature cache. */ #define RING_TRUST_KEY 1 /* A KEYORG on a primary key. */ #define RING_TRUST_UID 2 /* A KEYORG on a user id. */ /* The local only ring trust packet which OpenPGP declares as * implementation defined. GnuPG uses this to cache signature * verification status and since 2.1.18 also to convey information * about the origin of a key. Note that this packet is not part * struct packet_struct because we use it only local in the packet * parser and builder. */ typedef struct { unsigned int trustval; unsigned int sigcache; unsigned char subtype; /* The subtype of this ring trust packet. */ unsigned char keyorg; /* The origin of the key (KEYORG_*). */ u32 keyupdate; /* The wall time the key was last updated. */ char *url; /* NULL or the URL of the source. */ } PKT_ring_trust; /* A plaintext packet (see RFC 4880, 5.9). */ typedef struct { /* The length of data in BUF or 0 if unknown. */ u32 len; /* A buffer containing the data stored in the packet's body. */ iobuf_t buf; byte new_ctb; byte is_partial; /* partial length encoded */ /* The data's formatting. This is either 'b', 't', 'u', 'l' or '1' (however, the last two are deprecated). */ int mode; u32 timestamp; /* The name of the file. This can be at most 255 characters long, since namelen is just a byte in the serialized format. */ int namelen; char name[1]; } PKT_plaintext; typedef struct { int control; size_t datalen; char data[1]; } PKT_gpg_control; /* combine all packets into a union */ struct packet_struct { pkttype_t pkttype; union { void *generic; PKT_symkey_enc *symkey_enc; /* PKT_SYMKEY_ENC */ PKT_pubkey_enc *pubkey_enc; /* PKT_PUBKEY_ENC */ PKT_onepass_sig *onepass_sig; /* PKT_ONEPASS_SIG */ PKT_signature *signature; /* PKT_SIGNATURE */ PKT_public_key *public_key; /* PKT_PUBLIC_[SUB]KEY */ PKT_public_key *secret_key; /* PKT_SECRET_[SUB]KEY */ PKT_comment *comment; /* PKT_COMMENT */ PKT_user_id *user_id; /* PKT_USER_ID */ PKT_compressed *compressed; /* PKT_COMPRESSED */ PKT_encrypted *encrypted; /* PKT_ENCRYPTED[_MDC] */ PKT_mdc *mdc; /* PKT_MDC */ PKT_plaintext *plaintext; /* PKT_PLAINTEXT */ PKT_gpg_control *gpg_control; /* PKT_GPG_CONTROL */ } pkt; }; #define init_packet(a) do { (a)->pkttype = 0; \ (a)->pkt.generic = NULL; \ } while(0) /* A notation. See RFC 4880, Section 5.2.3.16. */ struct notation { /* The notation's name. */ char *name; /* If the notation is human readable, then the value is stored here as a NUL-terminated string. If it is not human readable a human readable approximation of the binary value _may_ be stored here. */ char *value; /* Sometimes we want to %-expand the value. In these cases, we save that transformed value here. */ char *altvalue; /* If the notation is not human readable, then the value is stored here. */ unsigned char *bdat; /* The amount of data stored in BDAT. Note: if this is 0 and BDAT is NULL, this does not necessarily mean that the value is human readable. It could be that we have a 0-length value. To determine whether the notation is human readable, always check if VALUE is not NULL. This works, because if a human-readable value has a length of 0, we will still allocate space for the NUL byte. */ size_t blen; struct { /* The notation is critical. */ unsigned int critical:1; /* The notation is human readable. */ unsigned int human:1; /* The notation should be deleted. */ unsigned int ignore:1; } flags; /* A field to facilitate creating a list of notations. */ struct notation *next; }; typedef struct notation *notation_t; /*-- mainproc.c --*/ void reset_literals_seen(void); int proc_packets (ctrl_t ctrl, void *ctx, iobuf_t a ); int proc_signature_packets (ctrl_t ctrl, void *ctx, iobuf_t a, strlist_t signedfiles, const char *sigfile ); int proc_signature_packets_by_fd (ctrl_t ctrl, void *anchor, IOBUF a, int signed_data_fd ); int proc_encryption_packets (ctrl_t ctrl, void *ctx, iobuf_t a); int list_packets( iobuf_t a ); const byte *issuer_fpr_raw (PKT_signature *sig, size_t *r_len); char *issuer_fpr_string (PKT_signature *sig); /*-- parse-packet.c --*/ void register_known_notation (const char *string); /* Sets the packet list mode to MODE (i.e., whether we are dumping a packet or not). Returns the current mode. This allows for temporarily suspending dumping by doing the following: int saved_mode = set_packet_list_mode (0); ... set_packet_list_mode (saved_mode); */ int set_packet_list_mode( int mode ); /* A context used with parse_packet. */ struct parse_packet_ctx_s { iobuf_t inp; /* The input stream with the packets. */ struct packet_struct last_pkt; /* The last parsed packet. */ int free_last_pkt; /* Indicates that LAST_PKT must be freed. */ int skip_meta; /* Skip ring trust packets. */ unsigned int n_parsed_packets; /* Number of parsed packets. */ }; typedef struct parse_packet_ctx_s *parse_packet_ctx_t; #define init_parse_packet(a,i) do { \ (a)->inp = (i); \ (a)->last_pkt.pkttype = 0; \ (a)->last_pkt.pkt.generic= NULL;\ (a)->free_last_pkt = 0; \ (a)->skip_meta = 0; \ (a)->n_parsed_packets = 0; \ } while (0) #define deinit_parse_packet(a) do { \ if ((a)->free_last_pkt) \ free_packet (NULL, (a)); \ } while (0) #if DEBUG_PARSE_PACKET /* There are debug functions and should not be used directly. */ int dbg_search_packet (parse_packet_ctx_t ctx, PACKET *pkt, off_t *retpos, int with_uid, const char* file, int lineno ); int dbg_parse_packet (parse_packet_ctx_t ctx, PACKET *ret_pkt, const char *file, int lineno); int dbg_copy_all_packets( iobuf_t inp, iobuf_t out, const char* file, int lineno ); int dbg_copy_some_packets( iobuf_t inp, iobuf_t out, off_t stopoff, const char* file, int lineno ); int dbg_skip_some_packets( iobuf_t inp, unsigned n, const char* file, int lineno ); #define search_packet( a,b,c,d ) \ dbg_search_packet( (a), (b), (c), (d), __FILE__, __LINE__ ) #define parse_packet( a, b ) \ dbg_parse_packet( (a), (b), __FILE__, __LINE__ ) #define copy_all_packets( a,b ) \ dbg_copy_all_packets((a),(b), __FILE__, __LINE__ ) #define copy_some_packets( a,b,c ) \ dbg_copy_some_packets((a),(b),(c), __FILE__, __LINE__ ) #define skip_some_packets( a,b ) \ dbg_skip_some_packets((a),(b), __FILE__, __LINE__ ) #else /* Return the next valid OpenPGP packet in *PKT. (This function will * skip any packets whose type is 0.) CTX must have been setup prior to * calling this function. * * Returns 0 on success, -1 if EOF is reached, and an error code * otherwise. In the case of an error, the packet in *PKT may be * partially constructed. As such, even if there is an error, it is * necessary to free *PKT to avoid a resource leak. To detect what * has been allocated, clear *PKT before calling this function. */ int parse_packet (parse_packet_ctx_t ctx, PACKET *pkt); /* Return the first OpenPGP packet in *PKT that contains a key (either * a public subkey, a public key, a secret subkey or a secret key) or, * if WITH_UID is set, a user id. * * Saves the position in the pipeline of the start of the returned * packet (according to iobuf_tell) in RETPOS, if it is not NULL. * * The return semantics are the same as parse_packet. */ int search_packet (parse_packet_ctx_t ctx, PACKET *pkt, off_t *retpos, int with_uid); /* Copy all packets (except invalid packets, i.e., those with a type * of 0) from INP to OUT until either an error occurs or EOF is * reached. * * Returns -1 when end of file is reached or an error code, if an * error occurred. (Note: this function never returns 0, because it * effectively keeps going until it gets an EOF.) */ int copy_all_packets (iobuf_t inp, iobuf_t out ); /* Like copy_all_packets, but stops at the first packet that starts at * or after STOPOFF (as indicated by iobuf_tell). * * Example: if STOPOFF is 100, the first packet in INP goes from * 0 to 110 and the next packet starts at offset 111, then the packet * starting at offset 0 will be completely processed (even though it * extends beyond STOPOFF) and the packet starting at offset 111 will * not be processed at all. */ int copy_some_packets (iobuf_t inp, iobuf_t out, off_t stopoff); /* Skips the next N packets from INP. * * If parsing a packet returns an error code, then the function stops * immediately and returns the error code. Note: in the case of an * error, this function does not indicate how many packets were * successfully processed. */ int skip_some_packets (iobuf_t inp, unsigned int n); #endif /* Parse a signature packet and store it in *SIG. The signature packet is read from INP. The OpenPGP header (the tag and the packet's length) have already been read; the next byte read from INP should be the first byte of the packet's contents. The packet's type (as extract from the tag) must be passed as PKTTYPE and the packet's length must be passed as PKTLEN. This is used as the upper bound on the amount of data read from INP. If the packet is shorter than PKTLEN, the data at the end will be silently skipped. If an error occurs, an error code will be returned. -1 means the EOF was encountered. 0 means parsing was successful. */ int parse_signature( iobuf_t inp, int pkttype, unsigned long pktlen, PKT_signature *sig ); /* Given a signature packet, either: * * - test whether there are any subpackets with the critical bit set * that we don't understand, * * - list the subpackets, or, * * - find a subpacket with a specific type. * * The WANT_HASHED flag indicates that the hashed area shall be * considered. * * REQTYPE indicates the type of operation. * * If REQTYPE is SIGSUBPKT_TEST_CRITICAL, then this function checks * whether there are any subpackets that have the critical bit and * which GnuPG cannot handle. If GnuPG understands all subpackets * whose critical bit is set, then this function returns simply * returns SUBPKTS. If there is a subpacket whose critical bit is set * and which GnuPG does not understand, then this function returns * NULL and, if START is not NULL, sets *START to the 1-based index of * the subpacket that violates the constraint. * * If REQTYPE is SIGSUBPKT_LIST_HASHED or SIGSUBPKT_LIST_UNHASHED, the * packets are dumped. Note: if REQTYPE is SIGSUBPKT_LIST_HASHED, * this function does not check whether the hash is correct; this is * merely an indication of the section that the subpackets came from. * * If REQTYPE is anything else, then this function interprets the * values as a subpacket type and looks for the first subpacket with * that type. If such a packet is found, *CRITICAL (if not NULL) is * set if the critical bit was set, *RET_N is set to the offset of the * subpacket's content within the SUBPKTS buffer, *START is set to the * 1-based index of the subpacket within the buffer, and returns * &SUBPKTS[*RET_N]. * * *START is the number of initial subpackets to not consider. Thus, * if *START is 2, then the first 2 subpackets are ignored. */ const byte *enum_sig_subpkt (PKT_signature *sig, int want_hashed, sigsubpkttype_t reqtype, size_t *ret_n, int *start, int *critical ); /* Shorthand for: * * enum_sig_subpkt (sig, want_hashed, reqtype, ret_n, NULL, NULL); */ const byte *parse_sig_subpkt (PKT_signature *sig, int want_hashed, sigsubpkttype_t reqtype, size_t *ret_n ); /* This calls parse_sig_subpkt first on the hashed signature area in * SIG and then, if that returns NULL, calls parse_sig_subpkt on the * unhashed subpacket area in SIG. */ const byte *parse_sig_subpkt2 (PKT_signature *sig, sigsubpkttype_t reqtype); /* Returns whether the N byte large buffer BUFFER is sufficient to hold a subpacket of type TYPE. Note: the buffer refers to the contents of the subpacket (not the header) and it must already be initialized: for some subpackets, it checks some internal constraints. Returns 0 if the size is acceptable. Returns -2 if the buffer is definitely too short. To check for an error, check whether the return value is less than 0. */ int parse_one_sig_subpkt( const byte *buffer, size_t n, int type ); /* Looks for revocation key subpackets (see RFC 4880 5.2.3.15) in the hashed area of the signature packet. Any that are found are added to SIG->REVKEY and SIG->NUMREVKEYS is updated appropriately. */ void parse_revkeys(PKT_signature *sig); /* Extract the attributes from the buffer at UID->ATTRIB_DATA and update UID->ATTRIBS and UID->NUMATTRIBS accordingly. */ int parse_attribute_subpkts(PKT_user_id *uid); /* Set the UID->NAME field according to the attributes. MAX_NAMELEN must be at least 71. */ void make_attribute_uidname(PKT_user_id *uid, size_t max_namelen); /* Allocate and initialize a new GPG control packet. DATA is the data to save in the packet. */ PACKET *create_gpg_control ( ctrlpkttype_t type, const byte *data, size_t datalen ); /*-- build-packet.c --*/ gpg_error_t build_keyblock_image (kbnode_t keyblock, iobuf_t *r_iobuf); int build_packet (iobuf_t out, PACKET *pkt); gpg_error_t build_packet_and_meta (iobuf_t out, PACKET *pkt); gpg_error_t gpg_mpi_write (iobuf_t out, gcry_mpi_t a, unsigned int *t_nwritten); gpg_error_t gpg_mpi_write_nohdr (iobuf_t out, gcry_mpi_t a); u32 calc_packet_length( PACKET *pkt ); void build_sig_subpkt( PKT_signature *sig, sigsubpkttype_t type, const byte *buffer, size_t buflen ); void build_sig_subpkt_from_sig (PKT_signature *sig, PKT_public_key *pksk); int delete_sig_subpkt(subpktarea_t *buffer, sigsubpkttype_t type ); void build_attribute_subpkt(PKT_user_id *uid,byte type, const void *buf,u32 buflen, const void *header,u32 headerlen); struct notation *string_to_notation(const char *string,int is_utf8); struct notation *blob_to_notation(const char *name, const char *data, size_t len); struct notation *sig_to_notation(PKT_signature *sig); void free_notation(struct notation *notation); /*-- free-packet.c --*/ void free_symkey_enc( PKT_symkey_enc *enc ); void free_pubkey_enc( PKT_pubkey_enc *enc ); void free_seckey_enc( PKT_signature *enc ); void release_public_key_parts( PKT_public_key *pk ); void free_public_key( PKT_public_key *key ); void free_attributes(PKT_user_id *uid); void free_user_id( PKT_user_id *uid ); void free_comment( PKT_comment *rem ); void free_packet (PACKET *pkt, parse_packet_ctx_t parsectx); prefitem_t *copy_prefs (const prefitem_t *prefs); PKT_public_key *copy_public_key( PKT_public_key *d, PKT_public_key *s ); PKT_signature *copy_signature( PKT_signature *d, PKT_signature *s ); PKT_user_id *scopy_user_id (PKT_user_id *sd ); int cmp_public_keys( PKT_public_key *a, PKT_public_key *b ); int cmp_signatures( PKT_signature *a, PKT_signature *b ); int cmp_user_ids( PKT_user_id *a, PKT_user_id *b ); /*-- sig-check.c --*/ /* Check a signature. This is shorthand for check_signature2 with the unnamed arguments passed as NULL. */ int check_signature (ctrl_t ctrl, PKT_signature *sig, gcry_md_hd_t digest); /* Check a signature. Looks up the public key from the key db. (If * R_PK is not NULL, it is stored at RET_PK.) DIGEST contains a * valid hash context that already includes the signed data. This * function adds the relevant meta-data to the hash before finalizing * it and verifying the signature. FOCRED_PK is usually NULL. */ gpg_error_t check_signature2 (ctrl_t ctrl, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen, PKT_public_key *forced_pk, u32 *r_expiredate, int *r_expired, int *r_revoked, PKT_public_key **r_pk); /*-- pubkey-enc.c --*/ gpg_error_t get_session_key (ctrl_t ctrl, struct pubkey_enc_list *k, DEK *dek); gpg_error_t get_override_session_key (DEK *dek, const char *string); /*-- compress.c --*/ int handle_compressed (ctrl_t ctrl, void *ctx, PKT_compressed *cd, int (*callback)(iobuf_t, void *), void *passthru ); /*-- encr-data.c --*/ int decrypt_data (ctrl_t ctrl, void *ctx, PKT_encrypted *ed, DEK *dek ); /*-- plaintext.c --*/ gpg_error_t get_output_file (const byte *embedded_name, int embedded_namelen, iobuf_t data, char **fnamep, estream_t *fpp); int handle_plaintext( PKT_plaintext *pt, md_filter_context_t *mfx, int nooutput, int clearsig ); int ask_for_detached_datafile( gcry_md_hd_t md, gcry_md_hd_t md2, const char *inname, int textmode ); /*-- sign.c --*/ int make_keysig_packet (ctrl_t ctrl, PKT_signature **ret_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_public_key *subpk, PKT_public_key *pksk, int sigclass, u32 timestamp, u32 duration, int (*mksubpkt)(PKT_signature *, void *), void *opaque, const char *cache_nonce); gpg_error_t update_keysig_packet (ctrl_t ctrl, PKT_signature **ret_sig, PKT_signature *orig_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_public_key *subpk, PKT_public_key *pksk, int (*mksubpkt)(PKT_signature *, void *), void *opaque ); /*-- keygen.c --*/ PKT_user_id *generate_user_id (kbnode_t keyblock, const char *uidstr); #endif /*G10_PACKET_H*/ diff --git a/g10/passphrase.c b/g10/passphrase.c index 99a2c0dc2..54a183e54 100644 --- a/g10/passphrase.c +++ b/g10/passphrase.c @@ -1,504 +1,504 @@ /* passphrase.c - Get a passphrase * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, * 2005, 2006, 2007, 2009, 2011 Free Software Foundation, Inc. * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include #include #include #include #include #include #include #ifdef HAVE_LOCALE_H #include #endif #ifdef HAVE_LANGINFO_CODESET #include #endif #include "gpg.h" #include "../common/util.h" #include "options.h" #include "../common/ttyio.h" #include "keydb.h" #include "main.h" #include "../common/i18n.h" #include "../common/status.h" #include "call-agent.h" #include "../common/shareddefs.h" static char *fd_passwd = NULL; static char *next_pw = NULL; static char *last_pw = NULL; int have_static_passphrase() { return (!!fd_passwd && (opt.batch || opt.pinentry_mode == PINENTRY_MODE_LOOPBACK)); } /* Return a static passphrase. The returned value is only valid as long as no other passphrase related function is called. NULL may be returned if no passphrase has been set; better use have_static_passphrase first. */ const char * get_static_passphrase (void) { return fd_passwd; } /**************** * Set the passphrase to be used for the next query and only for the next * one. */ void set_next_passphrase( const char *s ) { xfree(next_pw); next_pw = NULL; if ( s ) { next_pw = xmalloc_secure( strlen(s)+1 ); strcpy (next_pw, s ); } } /**************** * Get the last passphrase used in passphrase_to_dek. * Note: This removes the passphrase from this modules and * the caller must free the result. May return NULL: */ char * get_last_passphrase() { char *p = last_pw; last_pw = NULL; return p; } /* Here's an interesting question: since this passphrase was passed in on the command line, is there really any point in using secure memory for it? I'm going with 'yes', since it doesn't hurt, and might help in some small way (swapping). */ void set_passphrase_from_string(const char *pass) { xfree (fd_passwd); fd_passwd = xmalloc_secure(strlen(pass)+1); strcpy (fd_passwd, pass); } void read_passphrase_from_fd( int fd ) { int i, len; char *pw; if (! gnupg_fd_valid (fd)) log_fatal ("passphrase-fd is invalid: %s\n", strerror (errno)); if ( !opt.batch && opt.pinentry_mode != PINENTRY_MODE_LOOPBACK) { /* Not used but we have to do a dummy read, so that it won't end up at the begin of the message if the quite usual trick to prepend the passphtrase to the message is used. */ char buf[1]; while (!(read (fd, buf, 1) != 1 || *buf == '\n' )) ; *buf = 0; return; } for (pw = NULL, i = len = 100; ; i++ ) { if (i >= len-1 ) { char *pw2 = pw; len += 100; pw = xmalloc_secure( len ); if( pw2 ) { memcpy(pw, pw2, i ); xfree (pw2); } else i=0; } if (read( fd, pw+i, 1) != 1 || pw[i] == '\n' ) break; } pw[i] = 0; if (!opt.batch && opt.pinentry_mode != PINENTRY_MODE_LOOPBACK) tty_printf("\b\b\b \n" ); xfree ( fd_passwd ); fd_passwd = pw; } /* * Ask the GPG Agent for the passphrase. * If NOCACHE is set the symmetric passpharse caching will not be used. * * Note that TRYAGAIN_TEXT must not be translated. If CANCELED is not * NULL, the function does set it to 1 if the user canceled the * operation. If CACHEID is not NULL, it will be used as the cacheID * for the gpg-agent; if is NULL and a key fingerprint can be * computed, this will be used as the cacheid. */ static char * passphrase_get (int nocache, const char *cacheid, int repeat, const char *tryagain_text, int *canceled) { int rc; char *pw = NULL; char *orig_codeset; const char *my_cacheid; if (canceled) *canceled = 0; orig_codeset = i18n_switchto_utf8 (); if (!nocache && cacheid) my_cacheid = cacheid; else my_cacheid = NULL; if (tryagain_text) tryagain_text = _(tryagain_text); rc = agent_get_passphrase (my_cacheid, tryagain_text, NULL, _("Enter passphrase\n"), repeat, nocache, &pw); i18n_switchback (orig_codeset); if (!rc) ; else if (gpg_err_code (rc) == GPG_ERR_CANCELED || gpg_err_code (rc) == GPG_ERR_FULLY_CANCELED) { log_info (_("cancelled by user\n") ); if (canceled) *canceled = 1; } else { log_error (_("problem with the agent: %s\n"), gpg_strerror (rc)); /* Due to limitations in the API of the upper layers they consider an error as no passphrase entered. This works in most cases but not during key creation where this should definitely not happen and let it continue without requiring a passphrase. Given that now all the upper layers handle a cancel correctly, we simply set the cancel flag now for all errors from the agent. */ if (canceled) *canceled = 1; write_status_errcode ("get_passphrase", rc); } if (rc) { xfree (pw); pw = NULL; } return pw; } /* * Clear the cached passphrase with CACHEID. */ void passphrase_clear_cache (const char *cacheid) { int rc; rc = agent_clear_passphrase (cacheid); if (rc) log_error (_("problem with the agent: %s\n"), gpg_strerror (rc)); } /* Return a new DEK object using the string-to-key specifier S2K. * Returns NULL if the user canceled the passphrase entry and if * CANCELED is not NULL, sets it to true. * - * If CREATE is true a new passphrase sll be created. If NOCACHE is + * If CREATE is true a new passphrase will be created. If NOCACHE is * true the symmetric key caching will not be used. */ DEK * passphrase_to_dek (int cipher_algo, STRING2KEY *s2k, int create, int nocache, const char *tryagain_text, int *canceled) { char *pw = NULL; DEK *dek; STRING2KEY help_s2k; int dummy_canceled; char s2k_cacheidbuf[1+16+1]; char *s2k_cacheid = NULL; if (!canceled) canceled = &dummy_canceled; *canceled = 0; if (opt.no_symkey_cache) nocache = 1; /* Force no symmtric key caching. */ if ( !s2k ) { log_assert (create && !nocache); /* This is used for the old rfc1991 mode * Note: This must match the code in encode.c with opt.rfc1991 set */ memset (&help_s2k, 0, sizeof (help_s2k)); s2k = &help_s2k; s2k->hash_algo = S2K_DIGEST_ALGO; } /* Create a new salt or what else to be filled into the s2k for a new key. */ if (create && (s2k->mode == 1 || s2k->mode == 3)) { gcry_randomize (s2k->salt, 8, GCRY_STRONG_RANDOM); if ( s2k->mode == 3 ) { /* We delay the encoding until it is really needed. This is if we are going to dynamically calibrate it, we need to call out to gpg-agent and that should not be done during option processing in main(). */ if (!opt.s2k_count) opt.s2k_count = encode_s2k_iterations (agent_get_s2k_count ()); s2k->count = opt.s2k_count; } } /* If we do not have a passphrase available in NEXT_PW and status information are request, we print them now. */ if ( !next_pw && is_status_enabled() ) { char buf[50]; snprintf (buf, sizeof buf, "%d %d %d", cipher_algo, s2k->mode, s2k->hash_algo ); write_status_text ( STATUS_NEED_PASSPHRASE_SYM, buf ); } if ( next_pw ) { /* Simply return the passphrase we already have in NEXT_PW. */ pw = next_pw; next_pw = NULL; } else if ( have_static_passphrase () ) { /* Return the passphrase we have stored in FD_PASSWD. */ pw = xmalloc_secure ( strlen(fd_passwd)+1 ); strcpy ( pw, fd_passwd ); } else { if (!nocache && (s2k->mode == 1 || s2k->mode == 3)) { memset (s2k_cacheidbuf, 0, sizeof s2k_cacheidbuf); *s2k_cacheidbuf = 'S'; bin2hex (s2k->salt, 8, s2k_cacheidbuf + 1); s2k_cacheid = s2k_cacheidbuf; } if (opt.pinentry_mode == PINENTRY_MODE_LOOPBACK) { char buf[32]; snprintf (buf, sizeof (buf), "%u", 100); write_status_text (STATUS_INQUIRE_MAXLEN, buf); } /* Divert to the gpg-agent. */ pw = passphrase_get (create && nocache, s2k_cacheid, create? opt.passphrase_repeat : 0, tryagain_text, canceled); if (*canceled) { xfree (pw); write_status( STATUS_MISSING_PASSPHRASE ); return NULL; } } if ( !pw || !*pw ) write_status( STATUS_MISSING_PASSPHRASE ); /* Hash the passphrase and store it in a newly allocated DEK object. Keep a copy of the passphrase in LAST_PW for use by get_last_passphrase(). */ dek = xmalloc_secure_clear ( sizeof *dek ); dek->algo = cipher_algo; if ( (!pw || !*pw) && create) dek->keylen = 0; else { gpg_error_t err; dek->keylen = openpgp_cipher_get_algo_keylen (dek->algo); if (!(dek->keylen > 0 && dek->keylen <= DIM(dek->key))) BUG (); err = gcry_kdf_derive (pw, strlen (pw), s2k->mode == 3? GCRY_KDF_ITERSALTED_S2K : s2k->mode == 1? GCRY_KDF_SALTED_S2K : /* */ GCRY_KDF_SIMPLE_S2K, s2k->hash_algo, s2k->salt, 8, S2K_DECODE_COUNT(s2k->count), dek->keylen, dek->key); if (err) { log_error ("gcry_kdf_derive failed: %s", gpg_strerror (err)); xfree (pw); xfree (dek); write_status( STATUS_MISSING_PASSPHRASE ); return NULL; } } if (s2k_cacheid) memcpy (dek->s2k_cacheid, s2k_cacheid, sizeof dek->s2k_cacheid); xfree(last_pw); last_pw = pw; return dek; } /* Emit the USERID_HINT and the NEED_PASSPHRASE status messages. MAINKEYID may be NULL. */ void emit_status_need_passphrase (ctrl_t ctrl, u32 *keyid, u32 *mainkeyid, int pubkey_algo) { char buf[50]; char *us; us = get_long_user_id_string (ctrl, keyid); write_status_text (STATUS_USERID_HINT, us); xfree (us); snprintf (buf, sizeof buf, "%08lX%08lX %08lX%08lX %d 0", (ulong)keyid[0], (ulong)keyid[1], (ulong)(mainkeyid? mainkeyid[0]:keyid[0]), (ulong)(mainkeyid? mainkeyid[1]:keyid[1]), pubkey_algo); write_status_text (STATUS_NEED_PASSPHRASE, buf); } /* Return an allocated utf-8 string describing the key PK. If ESCAPED is true spaces and control characters are percent or plus escaped. MODE describes the use of the key description; use one of the FORMAT_KEYDESC_ macros. */ char * gpg_format_keydesc (ctrl_t ctrl, PKT_public_key *pk, int mode, int escaped) { char *uid; size_t uidlen; const char *algo_name; const char *timestr; char *orig_codeset; char *maink; char *desc; const char *prompt; const char *trailer = ""; int is_subkey; is_subkey = (pk->main_keyid[0] && pk->main_keyid[1] && pk->keyid[0] != pk->main_keyid[0] && pk->keyid[1] != pk->main_keyid[1]); algo_name = openpgp_pk_algo_name (pk->pubkey_algo); timestr = strtimestamp (pk->timestamp); uid = get_user_id (ctrl, is_subkey? pk->main_keyid:pk->keyid, &uidlen, NULL); orig_codeset = i18n_switchto_utf8 (); if (is_subkey) maink = xtryasprintf (_(" (main key ID %s)"), keystr (pk->main_keyid)); else maink = NULL; switch (mode) { case FORMAT_KEYDESC_NORMAL: prompt = _("Please enter the passphrase to unlock the" " OpenPGP secret key:"); break; case FORMAT_KEYDESC_IMPORT: prompt = _("Please enter the passphrase to import the" " OpenPGP secret key:"); break; case FORMAT_KEYDESC_EXPORT: if (is_subkey) prompt = _("Please enter the passphrase to export the" " OpenPGP secret subkey:"); else prompt = _("Please enter the passphrase to export the" " OpenPGP secret key:"); break; case FORMAT_KEYDESC_DELKEY: if (is_subkey) prompt = _("Do you really want to permanently delete the" " OpenPGP secret subkey key:"); else prompt = _("Do you really want to permanently delete the" " OpenPGP secret key:"); trailer = "?"; break; default: prompt = "?"; break; } desc = xtryasprintf (_("%s\n" "\"%.*s\"\n" "%u-bit %s key, ID %s,\n" "created %s%s.\n%s"), prompt, (int)uidlen, uid, nbits_from_pk (pk), algo_name, keystr (pk->keyid), timestr, maink?maink:"", trailer); xfree (maink); xfree (uid); i18n_switchback (orig_codeset); if (escaped) { char *tmp = percent_plus_escape (desc); xfree (desc); desc = tmp; } return desc; } diff --git a/g10/sig-check.c b/g10/sig-check.c index e622d9883..2534309dd 100644 --- a/g10/sig-check.c +++ b/g10/sig-check.c @@ -1,1256 +1,1257 @@ /* sig-check.c - Check a signature * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, * 2004, 2006 Free Software Foundation, Inc. * Copyright (C) 2015, 2016 g10 Code GmbH * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include #include #include #include #include "gpg.h" #include "../common/util.h" #include "packet.h" #include "keydb.h" #include "main.h" #include "../common/status.h" #include "../common/i18n.h" #include "options.h" #include "pkglue.h" #include "../common/compliance.h" static int check_signature_end (PKT_public_key *pk, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen, int *r_expired, int *r_revoked, PKT_public_key *ret_pk); static int check_signature_end_simple (PKT_public_key *pk, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen); /* Statistics for signature verification. */ struct { unsigned int total; /* Total number of verifications. */ unsigned int cached; /* Number of seen cache entries. */ unsigned int goodsig;/* Number of good verifications from the cache. */ unsigned int badsig; /* Number of bad verifications from the cache. */ } cache_stats; /* Dump verification stats. */ void sig_check_dump_stats (void) { log_info ("sig_cache: total=%u cached=%u good=%u bad=%u\n", cache_stats.total, cache_stats.cached, cache_stats.goodsig, cache_stats.badsig); } /* Check a signature. This is shorthand for check_signature2 with the unnamed arguments passed as NULL. */ int check_signature (ctrl_t ctrl, PKT_signature *sig, gcry_md_hd_t digest) { return check_signature2 (ctrl, sig, digest, NULL, 0, NULL, NULL, NULL, NULL, NULL); } /* Check a signature. * * Looks up the public key that created the signature (SIG->KEYID) * from the key db. Makes sure that the signature is valid (it was * not created prior to the key, the public key was created in the * past, and the signature does not include any unsupported critical * features), finishes computing the hash of the signature data, and * checks that the signature verifies the digest. If the key that * generated the signature is a subkey, this function also verifies * that there is a valid backsig from the subkey to the primary key. * Finally, if status fd is enabled and the signature class is 0x00 or * 0x01, then a STATUS_SIG_ID is emitted on the status fd. * * SIG is the signature to check. * * DIGEST contains a valid hash context that already includes the * signed data. This function adds the relevant meta-data from the * signature packet to compute the final hash. (See Section 5.2 of * RFC 4880: "The concatenation of the data being signed and the * signature data from the version number through the hashed subpacket * data (inclusive) is hashed.") * * EXTRAHASH and EXTRAHASHLEN is additional data which is hashed with * v5 signatures. They may be NULL to use the default. * * If FORCED_PK is not NULL this public key is used to verify the - * signature and no other public key is looked up. + * signature and no other public key is looked up. This is used to + * verify against a key included in the signature. * * If R_EXPIREDATE is not NULL, R_EXPIREDATE is set to the key's * expiry. * * If R_EXPIRED is not NULL, *R_EXPIRED is set to 1 if PK has expired * (0 otherwise). Note: PK being expired does not cause this function * to fail. * * If R_REVOKED is not NULL, *R_REVOKED is set to 1 if PK has been * revoked (0 otherwise). Note: PK being revoked does not cause this * function to fail. * * If R_PK is not NULL, the public key is stored at that address if it * was found; other wise NULL is stored. * * Returns 0 on success. An error code otherwise. */ gpg_error_t check_signature2 (ctrl_t ctrl, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen, PKT_public_key *forced_pk, u32 *r_expiredate, int *r_expired, int *r_revoked, PKT_public_key **r_pk) { int rc=0; PKT_public_key *pk; if (r_expiredate) *r_expiredate = 0; if (r_expired) *r_expired = 0; if (r_revoked) *r_revoked = 0; if (r_pk) *r_pk = NULL; pk = xtrycalloc (1, sizeof *pk); if (!pk) return gpg_error_from_syserror (); if ((rc=openpgp_md_test_algo(sig->digest_algo))) { /* We don't have this digest. */ } else if (!gnupg_digest_is_allowed (opt.compliance, 0, sig->digest_algo)) { /* Compliance failure. */ log_info (_("digest algorithm '%s' may not be used in %s mode\n"), gcry_md_algo_name (sig->digest_algo), gnupg_compliance_option_string (opt.compliance)); rc = gpg_error (GPG_ERR_DIGEST_ALGO); } else if ((rc=openpgp_pk_test_algo(sig->pubkey_algo))) { /* We don't have this pubkey algo. */ } else if (!gcry_md_is_enabled (digest,sig->digest_algo)) { /* Sanity check that the md has a context for the hash that the * sig is expecting. This can happen if a onepass sig header * does not match the actual sig, and also if the clearsign * "Hash:" header is missing or does not match the actual sig. */ log_info(_("WARNING: signature digest conflict in message\n")); rc = gpg_error (GPG_ERR_GENERAL); } else if (get_pubkey_for_sig (ctrl, pk, sig, forced_pk)) rc = gpg_error (GPG_ERR_NO_PUBKEY); else if (!gnupg_pk_is_allowed (opt.compliance, PK_USE_VERIFICATION, pk->pubkey_algo, pk->pkey, nbits_from_pk (pk), NULL)) { /* Compliance failure. */ log_error (_("key %s may not be used for signing in %s mode\n"), keystr_from_pk (pk), gnupg_compliance_option_string (opt.compliance)); rc = gpg_error (GPG_ERR_PUBKEY_ALGO); } else if (!pk->flags.valid) { /* You cannot have a good sig from an invalid key. */ rc = gpg_error (GPG_ERR_BAD_PUBKEY); } else { if (r_expiredate) *r_expiredate = pk->expiredate; rc = check_signature_end (pk, sig, digest, extrahash, extrahashlen, r_expired, r_revoked, NULL); /* Check the backsig. This is a back signature (0x19) from * the subkey on the primary key. The idea here is that it * should not be possible for someone to "steal" subkeys and * claim them as their own. The attacker couldn't actually * use the subkey, but they could try and claim ownership of * any signatures issued by it. */ if (!rc && !pk->flags.primary && pk->flags.backsig < 2) { if (!pk->flags.backsig) { log_info (_("WARNING: signing subkey %s is not" " cross-certified\n"),keystr_from_pk(pk)); log_info (_("please see %s for more information\n"), "https://gnupg.org/faq/subkey-cross-certify.html"); /* The default option --require-cross-certification * makes this warning an error. */ if (opt.flags.require_cross_cert) rc = gpg_error (GPG_ERR_GENERAL); } else if(pk->flags.backsig == 1) { log_info (_("WARNING: signing subkey %s has an invalid" " cross-certification\n"), keystr_from_pk(pk)); rc = gpg_error (GPG_ERR_GENERAL); } } } if( !rc && sig->sig_class < 2 && is_status_enabled() ) { /* This signature id works best with DLP algorithms because * they use a random parameter for every signature. Instead of * this sig-id we could have also used the hash of the document * and the timestamp, but the drawback of this is, that it is * not possible to sign more than one identical document within * one second. Some remote batch processing applications might * like this feature here. * * Note that before 2.0.10, we used RIPE-MD160 for the hash * and accidentally didn't include the timestamp and algorithm * information in the hash. Given that this feature is not * commonly used and that a replay attacks detection should * not solely be based on this feature (because it does not * work with RSA), we take the freedom and switch to SHA-1 * with 2.0.10 to take advantage of hardware supported SHA-1 * implementations. We also include the missing information * in the hash. Note also the SIG_ID as computed by gpg 1.x * and gpg 2.x didn't matched either because 2.x used to print * MPIs not in PGP format. */ u32 a = sig->timestamp; int nsig = pubkey_get_nsig( sig->pubkey_algo ); unsigned char *p, *buffer; size_t n, nbytes; int i; char hashbuf[20]; /* We use SHA-1 here. */ nbytes = 6; for (i=0; i < nsig; i++ ) { if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0, &n, sig->data[i])) BUG(); nbytes += n; } /* Make buffer large enough to be later used as output buffer. */ if (nbytes < 100) nbytes = 100; nbytes += 10; /* Safety margin. */ /* Fill and hash buffer. */ buffer = p = xmalloc (nbytes); *p++ = sig->pubkey_algo; *p++ = sig->digest_algo; *p++ = (a >> 24) & 0xff; *p++ = (a >> 16) & 0xff; *p++ = (a >> 8) & 0xff; *p++ = a & 0xff; nbytes -= 6; for (i=0; i < nsig; i++ ) { if (gcry_mpi_print (GCRYMPI_FMT_PGP, p, nbytes, &n, sig->data[i])) BUG(); p += n; nbytes -= n; } gcry_md_hash_buffer (GCRY_MD_SHA1, hashbuf, buffer, p-buffer); p = make_radix64_string (hashbuf, 20); sprintf (buffer, "%s %s %lu", p, strtimestamp (sig->timestamp), (ulong)sig->timestamp); xfree (p); write_status_text (STATUS_SIG_ID, buffer); xfree (buffer); } if (r_pk) *r_pk = pk; else { release_public_key_parts (pk); xfree (pk); } return rc; } /* The signature SIG was generated with the public key PK. Check * whether the signature is valid in the following sense: * * - Make sure the public key was created before the signature was * generated. * * - Make sure the public key was created in the past * * - Check whether PK has expired (set *R_EXPIRED to 1 if so and 0 * otherwise) * * - Check whether PK has been revoked (set *R_REVOKED to 1 if so * and 0 otherwise). * * If either of the first two tests fail, returns an error code. * Otherwise returns 0. (Thus, this function doesn't fail if the * public key is expired or revoked.) */ static int check_signature_metadata_validity (PKT_public_key *pk, PKT_signature *sig, int *r_expired, int *r_revoked) { u32 cur_time; if (r_expired) *r_expired = 0; if (r_revoked) *r_revoked = 0; if (pk->timestamp > sig->timestamp ) { ulong d = pk->timestamp - sig->timestamp; if ( d < 86400 ) { log_info (ngettext ("public key %s is %lu second newer than the signature\n", "public key %s is %lu seconds newer than the signature\n", d), keystr_from_pk (pk), d); } else { d /= 86400; log_info (ngettext ("public key %s is %lu day newer than the signature\n", "public key %s is %lu days newer than the signature\n", d), keystr_from_pk (pk), d); } if (!opt.ignore_time_conflict) return GPG_ERR_TIME_CONFLICT; /* pubkey newer than signature. */ } cur_time = make_timestamp (); if (pk->timestamp > cur_time) { ulong d = pk->timestamp - cur_time; if (d < 86400) { log_info (ngettext("key %s was created %lu second" " in the future (time warp or clock problem)\n", "key %s was created %lu seconds" " in the future (time warp or clock problem)\n", d), keystr_from_pk (pk), d); } else { d /= 86400; log_info (ngettext("key %s was created %lu day" " in the future (time warp or clock problem)\n", "key %s was created %lu days" " in the future (time warp or clock problem)\n", d), keystr_from_pk (pk), d); } if (!opt.ignore_time_conflict) return GPG_ERR_TIME_CONFLICT; } /* Check whether the key has expired. We check the has_expired * flag which is set after a full evaluation of the key (getkey.c) * as well as a simple compare to the current time in case the * merge has for whatever reasons not been done. */ if (pk->has_expired || (pk->expiredate && pk->expiredate < cur_time)) { char buf[11]; if (opt.verbose) log_info (_("Note: signature key %s expired %s\n"), keystr_from_pk(pk), asctimestamp( pk->expiredate ) ); snprintf (buf, sizeof buf, "%lu",(ulong)pk->expiredate); write_status_text (STATUS_KEYEXPIRED, buf); if (r_expired) *r_expired = 1; } if (pk->flags.revoked) { if (opt.verbose) log_info (_("Note: signature key %s has been revoked\n"), keystr_from_pk(pk)); if (r_revoked) *r_revoked=1; } return 0; } /* Finish generating a signature and check it. Concretely: make sure * that the signature is valid (it was not created prior to the key, * the public key was created in the past, and the signature does not * include any unsupported critical features), finish computing the * digest by adding the relevant data from the signature packet, and * check that the signature verifies the digest. * * DIGEST contains a hash context, which has already hashed the signed * data. This function adds the relevant meta-data from the signature * packet to compute the final hash. (See Section 5.2 of RFC 4880: * "The concatenation of the data being signed and the signature data * from the version number through the hashed subpacket data * (inclusive) is hashed.") * * SIG is the signature to check. * * PK is the public key used to generate the signature. * * If R_EXPIRED is not NULL, *R_EXPIRED is set to 1 if PK has expired * (0 otherwise). Note: PK being expired does not cause this function * to fail. * * If R_REVOKED is not NULL, *R_REVOKED is set to 1 if PK has been * revoked (0 otherwise). Note: PK being revoked does not cause this * function to fail. * * If RET_PK is not NULL, PK is copied into RET_PK on success. * * Returns 0 on success. An error code other. */ static int check_signature_end (PKT_public_key *pk, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen, int *r_expired, int *r_revoked, PKT_public_key *ret_pk) { int rc = 0; if ((rc = check_signature_metadata_validity (pk, sig, r_expired, r_revoked))) return rc; if ((rc = check_signature_end_simple (pk, sig, digest, extrahash, extrahashlen))) return rc; if (!rc && ret_pk) copy_public_key(ret_pk,pk); return rc; } /* This function is similar to check_signature_end, but it only checks * whether the signature was generated by PK. It does not check * expiration, revocation, etc. */ static int check_signature_end_simple (PKT_public_key *pk, PKT_signature *sig, gcry_md_hd_t digest, const void *extrahash, size_t extrahashlen) { gcry_mpi_t result = NULL; int rc = 0; const struct weakhash *weak; if (!opt.flags.allow_weak_digest_algos) { for (weak = opt.weak_digests; weak; weak = weak->next) if (sig->digest_algo == weak->algo) { print_digest_rejected_note(sig->digest_algo); return GPG_ERR_DIGEST_ALGO; } } /* For key signatures check that the key has a cert usage. We may * do this only for subkeys because the primary may always issue key * signature. The latter may not be reflected in the pubkey_usage * field because we need to check the key signatures to extract the * key usage. */ if (!pk->flags.primary && IS_CERT (sig) && !(pk->pubkey_usage & PUBKEY_USAGE_CERT)) { rc = gpg_error (GPG_ERR_WRONG_KEY_USAGE); if (!opt.quiet) log_info (_("bad key signature from key %s: %s (0x%02x, 0x%x)\n"), keystr_from_pk (pk), gpg_strerror (rc), sig->sig_class, pk->pubkey_usage); return rc; } /* For data signatures check that the key has sign usage. */ if (!IS_BACK_SIG (sig) && IS_SIG (sig) && !(pk->pubkey_usage & PUBKEY_USAGE_SIG)) { rc = gpg_error (GPG_ERR_WRONG_KEY_USAGE); if (!opt.quiet) log_info (_("bad data signature from key %s: %s (0x%02x, 0x%x)\n"), keystr_from_pk (pk), gpg_strerror (rc), sig->sig_class, pk->pubkey_usage); return rc; } /* Make sure the digest algo is enabled (in case of a detached * signature). */ gcry_md_enable (digest, sig->digest_algo); /* Complete the digest. */ if (sig->version >= 4) gcry_md_putc (digest, sig->version); gcry_md_putc( digest, sig->sig_class ); if (sig->version < 4) { u32 a = sig->timestamp; gcry_md_putc (digest, ((a >> 24) & 0xff)); gcry_md_putc (digest, ((a >> 16) & 0xff)); gcry_md_putc (digest, ((a >> 8) & 0xff)); gcry_md_putc (digest, ( a & 0xff)); } else { byte buf[10]; int i; size_t n; gcry_md_putc (digest, sig->pubkey_algo); gcry_md_putc (digest, sig->digest_algo); if (sig->hashed) { n = sig->hashed->len; gcry_md_putc (digest, (n >> 8) ); gcry_md_putc (digest, n ); gcry_md_write (digest, sig->hashed->data, n); n += 6; } else { /* Two octets for the (empty) length of the hashed * section. */ gcry_md_putc (digest, 0); gcry_md_putc (digest, 0); n = 6; } /* Hash data from the literal data packet. */ if (sig->version >= 5 && (sig->sig_class == 0x00 || sig->sig_class == 0x01)) { /* - One octet content format * - File name (one octet length followed by the name) * - Four octet timestamp */ if (extrahash && extrahashlen) gcry_md_write (digest, extrahash, extrahashlen); else /* Detached signature. */ { memset (buf, 0, 6); gcry_md_write (digest, buf, 6); } } /* Add some magic per Section 5.2.4 of RFC 4880. */ i = 0; buf[i++] = sig->version; buf[i++] = 0xff; if (sig->version >= 5) { #if SIZEOF_SIZE_T > 4 buf[i++] = n >> 56; buf[i++] = n >> 48; buf[i++] = n >> 40; buf[i++] = n >> 32; #else buf[i++] = 0; buf[i++] = 0; buf[i++] = 0; buf[i++] = 0; #endif } buf[i++] = n >> 24; buf[i++] = n >> 16; buf[i++] = n >> 8; buf[i++] = n; gcry_md_write (digest, buf, i); } gcry_md_final( digest ); /* Convert the digest to an MPI. */ result = encode_md_value (pk, digest, sig->digest_algo ); if (!result) return GPG_ERR_GENERAL; /* Verify the signature. */ if (DBG_CLOCK && sig->sig_class <= 0x01) log_clock ("enter pk_verify"); rc = pk_verify( pk->pubkey_algo, result, sig->data, pk->pkey ); if (DBG_CLOCK && sig->sig_class <= 0x01) log_clock ("leave pk_verify"); gcry_mpi_release (result); if (!rc && sig->flags.unknown_critical) { log_info(_("assuming bad signature from key %s" " due to an unknown critical bit\n"),keystr_from_pk(pk)); rc = GPG_ERR_BAD_SIGNATURE; } return rc; } /* Add a uid node to a hash context. See section 5.2.4, paragraph 4 * of RFC 4880. */ static void hash_uid_packet (PKT_user_id *uid, gcry_md_hd_t md, PKT_signature *sig ) { if (uid->attrib_data) { if (sig->version >= 4) { byte buf[5]; buf[0] = 0xd1; /* packet of type 17 */ buf[1] = uid->attrib_len >> 24; /* always use 4 length bytes */ buf[2] = uid->attrib_len >> 16; buf[3] = uid->attrib_len >> 8; buf[4] = uid->attrib_len; gcry_md_write( md, buf, 5 ); } gcry_md_write( md, uid->attrib_data, uid->attrib_len ); } else { if (sig->version >= 4) { byte buf[5]; buf[0] = 0xb4; /* indicates a userid packet */ buf[1] = uid->len >> 24; /* always use 4 length bytes */ buf[2] = uid->len >> 16; buf[3] = uid->len >> 8; buf[4] = uid->len; gcry_md_write( md, buf, 5 ); } gcry_md_write( md, uid->name, uid->len ); } } static void cache_sig_result ( PKT_signature *sig, int result ) { if (!result) { sig->flags.checked = 1; sig->flags.valid = 1; } else if (gpg_err_code (result) == GPG_ERR_BAD_SIGNATURE) { sig->flags.checked = 1; sig->flags.valid = 0; } else { sig->flags.checked = 0; sig->flags.valid = 0; } } /* SIG is a key revocation signature. Check if this signature was * generated by any of the public key PK's designated revokers. * * PK is the public key that SIG allegedly revokes. * * SIG is the revocation signature to check. * * This function avoids infinite recursion, which can happen if two * keys are designed revokers for each other and they revoke each * other. This is done by observing that if a key A is revoked by key * B we still consider the revocation to be valid even if B is * revoked. Thus, we don't need to determine whether B is revoked to * determine whether A has been revoked by B, we just need to check * the signature. * * Returns 0 if sig is valid (i.e. pk is revoked), non-0 if not * revoked. We are careful to make sure that GPG_ERR_NO_PUBKEY is * only returned when a revocation signature is from a valid * revocation key designated in a revkey subpacket, but the revocation * key itself isn't present. * * XXX: This code will need to be modified if gpg ever becomes * multi-threaded. Note that this guarantees that a designated * revocation sig will never be considered valid unless it is actually * valid, as well as being issued by a revocation key in a valid * direct signature. Note also that this is written so that a revoked * revoker can still issue revocations: i.e. If A revokes B, but A is * revoked, B is still revoked. I'm not completely convinced this is * the proper behavior, but it matches how PGP does it. -dms */ int check_revocation_keys (ctrl_t ctrl, PKT_public_key *pk, PKT_signature *sig) { static int busy=0; int i; int rc = GPG_ERR_GENERAL; log_assert (IS_KEY_REV(sig)); log_assert ((sig->keyid[0]!=pk->keyid[0]) || (sig->keyid[0]!=pk->keyid[1])); /* Avoid infinite recursion. Consider the following: * * - We want to check if A is revoked. * * - C is a designated revoker for B and has revoked B. * * - B is a designated revoker for A and has revoked A. * * When checking if A is revoked (in merge_selfsigs_main), we * observe that A has a designed revoker. As such, we call this * function. This function sees that there is a valid revocation * signature, which is signed by B. It then calls check_signature() * to verify that the signature is good. To check the sig, we need * to lookup B. Looking up B means calling merge_selfsigs_main, * which checks whether B is revoked, which calls this function to * see if B was revoked by some key. * * In this case, the added level of indirection doesn't hurt. It * just means a bit more work. However, if C == A, then we'd end up * in a loop. But, it doesn't make sense to look up C anyways: even * if B is revoked, we conservatively consider a valid revocation * signed by B to revoke A. Since this is the only place where this * type of recursion can occur, we simply cause this function to * fail if it is entered recursively. */ if (busy) { /* Return an error (i.e. not revoked), but mark the pk as uncacheable as we don't really know its revocation status until it is checked directly. */ pk->flags.dont_cache = 1; return rc; } busy=1; /* es_printf("looking at %08lX with a sig from %08lX\n",(ulong)pk->keyid[1], (ulong)sig->keyid[1]); */ /* is the issuer of the sig one of our revokers? */ if( !pk->revkey && pk->numrevkeys ) BUG(); else for(i=0;inumrevkeys;i++) { /* The revoker's keyid. */ u32 keyid[2]; keyid_from_fingerprint (ctrl, pk->revkey[i].fpr, pk->revkey[i].fprlen, keyid); if(keyid[0]==sig->keyid[0] && keyid[1]==sig->keyid[1]) /* The signature was generated by a designated revoker. Verify the signature. */ { gcry_md_hd_t md; if (gcry_md_open (&md, sig->digest_algo, 0)) BUG (); hash_public_key(md,pk); /* Note: check_signature only checks that the signature is good. It does not fail if the key is revoked. */ rc = check_signature (ctrl, sig, md); cache_sig_result(sig,rc); gcry_md_close (md); break; } } busy=0; return rc; } /* Check that the backsig BACKSIG from the subkey SUB_PK to its * primary key MAIN_PK is valid. * * Backsigs (0x19) have the same format as binding sigs (0x18), but * this function is simpler than check_key_signature in a few ways. * For example, there is no support for expiring backsigs since it is * questionable what such a thing actually means. Note also that the * sig cache check here, unlike other sig caches in GnuPG, is not * persistent. */ int check_backsig (PKT_public_key *main_pk,PKT_public_key *sub_pk, PKT_signature *backsig) { gcry_md_hd_t md; int rc; /* Always check whether the algorithm is available. Although gcry_md_open would throw an error, some libgcrypt versions will print a debug message in that case too. */ if ((rc=openpgp_md_test_algo (backsig->digest_algo))) return rc; if(!opt.no_sig_cache && backsig->flags.checked) return backsig->flags.valid? 0 : gpg_error (GPG_ERR_BAD_SIGNATURE); rc = gcry_md_open (&md, backsig->digest_algo,0); if (!rc) { hash_public_key(md,main_pk); hash_public_key(md,sub_pk); rc = check_signature_end (sub_pk, backsig, md, NULL, 0, NULL, NULL, NULL); cache_sig_result(backsig,rc); gcry_md_close(md); } return rc; } /* Check that a signature over a key is valid. This is a * specialization of check_key_signature2 with the unnamed parameters * passed as NULL. See the documentation for that function for more * details. */ int check_key_signature (ctrl_t ctrl, kbnode_t root, kbnode_t node, int *is_selfsig) { return check_key_signature2 (ctrl, root, node, NULL, NULL, is_selfsig, NULL, NULL); } /* Returns whether SIGNER generated the signature SIG over the packet * PACKET, which is a key, subkey or uid, and comes from the key block * KB. (KB is PACKET's corresponding keyblock; we don't assume that * SIG has been added to the keyblock.) * * If SIGNER is set, then checks whether SIGNER generated the * signature. Otherwise, uses SIG->KEYID to find the alleged signer. * This parameter can be used to effectively override the alleged * signer that is stored in SIG. * * KB may be NULL if SIGNER is set. * * Unlike check_key_signature, this function ignores any cached * results! That is, it does not consider SIG->FLAGS.CHECKED and * SIG->FLAGS.VALID nor does it set them. * * This doesn't check the signature's semantic mean. Concretely, it * doesn't check whether a non-self signed revocation signature was * created by a designated revoker. In fact, it doesn't return an * error for a binding generated by a completely different key! * * Returns 0 if the signature is valid. Returns GPG_ERR_SIG_CLASS if * this signature can't be over PACKET. Returns GPG_ERR_NOT_FOUND if * the key that generated the signature (according to SIG) could not * be found. Returns GPG_ERR_BAD_SIGNATURE if the signature is bad. * Other errors codes may be returned if something else goes wrong. * * IF IS_SELFSIG is not NULL, sets *IS_SELFSIG to 1 if this is a * self-signature (by the key's primary key) or 0 if not. * * If RET_PK is not NULL, returns a copy of the public key that * generated the signature (i.e., the signer) on success. This must * be released by the caller using release_public_key_parts (). */ gpg_error_t check_signature_over_key_or_uid (ctrl_t ctrl, PKT_public_key *signer, PKT_signature *sig, KBNODE kb, PACKET *packet, int *is_selfsig, PKT_public_key *ret_pk) { int rc; PKT_public_key *pripk = kb->pkt->pkt.public_key; gcry_md_hd_t md; int signer_alloced = 0; int stub_is_selfsig; if (!is_selfsig) is_selfsig = &stub_is_selfsig; rc = openpgp_pk_test_algo (sig->pubkey_algo); if (rc) return rc; rc = openpgp_md_test_algo (sig->digest_algo); if (rc) return rc; /* A signature's class indicates the type of packet that it signs. */ if (IS_BACK_SIG (sig) || IS_KEY_SIG (sig) || IS_KEY_REV (sig)) { /* Key revocations can only be over primary keys. */ if (packet->pkttype != PKT_PUBLIC_KEY) return gpg_error (GPG_ERR_SIG_CLASS); } else if (IS_SUBKEY_SIG (sig) || IS_SUBKEY_REV (sig)) { if (packet->pkttype != PKT_PUBLIC_SUBKEY) return gpg_error (GPG_ERR_SIG_CLASS); } else if (IS_UID_SIG (sig) || IS_UID_REV (sig)) { if (packet->pkttype != PKT_USER_ID) return gpg_error (GPG_ERR_SIG_CLASS); } else return gpg_error (GPG_ERR_SIG_CLASS); /* PACKET is the right type for SIG. */ if (signer) { if (signer->keyid[0] == pripk->keyid[0] && signer->keyid[1] == pripk->keyid[1]) *is_selfsig = 1; else *is_selfsig = 0; } else { /* Get the signer. If possible, avoid a look up. */ if (sig->keyid[0] == pripk->keyid[0] && sig->keyid[1] == pripk->keyid[1]) { /* Issued by the primary key. */ signer = pripk; *is_selfsig = 1; } else { /* See if one of the subkeys was the signer (although this * is extremely unlikely). */ kbnode_t ctx = NULL; kbnode_t n; while ((n = walk_kbnode (kb, &ctx, 0))) { PKT_public_key *subk; if (n->pkt->pkttype != PKT_PUBLIC_SUBKEY) continue; subk = n->pkt->pkt.public_key; if (sig->keyid[0] == subk->keyid[0] && sig->keyid[1] == subk->keyid[1]) { /* Issued by a subkey. */ signer = subk; break; } } if (! signer) { /* Signer by some other key. */ *is_selfsig = 0; if (ret_pk) { signer = ret_pk; /* FIXME: Using memset here is probematic because it * assumes that there are no allocated fields in * SIGNER. */ memset (signer, 0, sizeof (*signer)); signer_alloced = 1; } else { signer = xmalloc_clear (sizeof (*signer)); signer_alloced = 2; } if (IS_CERT (sig)) signer->req_usage = PUBKEY_USAGE_CERT; rc = get_pubkey_for_sig (ctrl, signer, sig, NULL); if (rc) { xfree (signer); signer = NULL; signer_alloced = 0; goto leave; } } } } /* We checked above that we supported this algo, so an error here is * a bug. */ if (gcry_md_open (&md, sig->digest_algo, 0)) BUG (); /* Hash the relevant data. */ if (IS_KEY_SIG (sig) || IS_KEY_REV (sig)) { log_assert (packet->pkttype == PKT_PUBLIC_KEY); hash_public_key (md, packet->pkt.public_key); rc = check_signature_end_simple (signer, sig, md, NULL, 0); } else if (IS_BACK_SIG (sig)) { log_assert (packet->pkttype == PKT_PUBLIC_KEY); hash_public_key (md, packet->pkt.public_key); hash_public_key (md, signer); rc = check_signature_end_simple (signer, sig, md, NULL, 0); } else if (IS_SUBKEY_SIG (sig) || IS_SUBKEY_REV (sig)) { log_assert (packet->pkttype == PKT_PUBLIC_SUBKEY); hash_public_key (md, pripk); hash_public_key (md, packet->pkt.public_key); rc = check_signature_end_simple (signer, sig, md, NULL, 0); } else if (IS_UID_SIG (sig) || IS_UID_REV (sig)) { log_assert (packet->pkttype == PKT_USER_ID); if (sig->digest_algo == DIGEST_ALGO_SHA1 && !*is_selfsig && !opt.flags.allow_weak_key_signatures) { /* If the signature was created using SHA-1 we consider this * signature invalid because it makes it possible to mount a * chosen-prefix collision. We don't do this for * self-signatures, though. */ print_sha1_keysig_rejected_note (); rc = gpg_error (GPG_ERR_DIGEST_ALGO); } else { hash_public_key (md, pripk); hash_uid_packet (packet->pkt.user_id, md, sig); rc = check_signature_end_simple (signer, sig, md, NULL, 0); } } else { /* We should never get here. (The first if above should have * already caught this error.) */ BUG (); } gcry_md_close (md); leave: if (! rc && ret_pk && ret_pk != signer) copy_public_key (ret_pk, signer); if (signer_alloced) { /* We looked up SIGNER; it is not a pointer into KB. */ release_public_key_parts (signer); /* Free if we also allocated the memory. */ if (signer_alloced == 2) xfree (signer); } return rc; } /* Check that a signature over a key (e.g., a key revocation, key * binding, user id certification, etc.) is valid. If the function * detects a self-signature, it uses the public key from the specified * key block and does not bother looking up the key specified in the * signature packet. * * ROOT is a keyblock. * * NODE references a signature packet that appears in the keyblock * that should be verified. * * If CHECK_PK is set, the specified key is sometimes preferred for * verifying signatures. See the implementation for details. * * If RET_PK is not NULL, the public key that successfully verified * the signature is copied into *RET_PK. * * If IS_SELFSIG is not NULL, *IS_SELFSIG is set to 1 if NODE is a * self-signature. * * If R_EXPIREDATE is not NULL, *R_EXPIREDATE is set to the expiry * date. * * If R_EXPIRED is not NULL, *R_EXPIRED is set to 1 if PK has been * expired (0 otherwise). Note: PK being revoked does not cause this * function to fail. * * * If OPT.NO_SIG_CACHE is not set, this function will first check if * the result of a previous verification is already cached in the * signature packet's data structure. * * TODO: add r_revoked here as well. It has the same problems as * r_expiredate and r_expired and the cache [nw]. Which problems [wk]? */ int check_key_signature2 (ctrl_t ctrl, kbnode_t root, kbnode_t node, PKT_public_key *check_pk, PKT_public_key *ret_pk, int *is_selfsig, u32 *r_expiredate, int *r_expired ) { PKT_public_key *pk; PKT_signature *sig; int algo; int rc; if (is_selfsig) *is_selfsig = 0; if (r_expiredate) *r_expiredate = 0; if (r_expired) *r_expired = 0; log_assert (node->pkt->pkttype == PKT_SIGNATURE); log_assert (root->pkt->pkttype == PKT_PUBLIC_KEY); pk = root->pkt->pkt.public_key; sig = node->pkt->pkt.signature; algo = sig->digest_algo; /* Check whether we have cached the result of a previous signature * check. Note that we may no longer have the pubkey or hash * needed to verify a sig, but can still use the cached value. A * cache refresh detects and clears these cases. */ if ( !opt.no_sig_cache ) { cache_stats.total++; if (sig->flags.checked) /* Cached status available. */ { cache_stats.cached++; if (is_selfsig) { u32 keyid[2]; keyid_from_pk (pk, keyid); if (keyid[0] == sig->keyid[0] && keyid[1] == sig->keyid[1]) *is_selfsig = 1; } /* BUG: This is wrong for non-self-sigs... needs to be the * actual pk. */ rc = check_signature_metadata_validity (pk, sig, r_expired, NULL); if (rc) return rc; if (sig->flags.valid) { cache_stats.goodsig++; return 0; } cache_stats.badsig++; return gpg_error (GPG_ERR_BAD_SIGNATURE); } } rc = openpgp_pk_test_algo(sig->pubkey_algo); if (rc) return rc; rc = openpgp_md_test_algo(algo); if (rc) return rc; if (IS_KEY_REV (sig)) { u32 keyid[2]; keyid_from_pk( pk, keyid ); /* Is it a designated revoker? */ if (keyid[0] != sig->keyid[0] || keyid[1] != sig->keyid[1]) rc = check_revocation_keys (ctrl, pk, sig); else { rc = check_signature_metadata_validity (pk, sig, r_expired, NULL); if (! rc) rc = check_signature_over_key_or_uid (ctrl, pk, sig, root, root->pkt, is_selfsig, ret_pk); } } else if (IS_SUBKEY_REV (sig) || IS_SUBKEY_SIG (sig)) { kbnode_t snode = find_prev_kbnode (root, node, PKT_PUBLIC_SUBKEY); if (snode) { rc = check_signature_metadata_validity (pk, sig, r_expired, NULL); if (! rc) { /* A subkey revocation (0x28) must be a self-sig, but a * subkey signature (0x18) needn't be. */ rc = check_signature_over_key_or_uid (ctrl, IS_SUBKEY_SIG (sig) ? NULL : pk, sig, root, snode->pkt, is_selfsig, ret_pk); } } else { if (opt.verbose) { if (IS_SUBKEY_REV (sig)) log_info (_("key %s: no subkey for subkey" " revocation signature\n"), keystr_from_pk(pk)); else if (sig->sig_class == 0x18) log_info(_("key %s: no subkey for subkey" " binding signature\n"), keystr_from_pk(pk)); } rc = GPG_ERR_SIG_CLASS; } } else if (IS_KEY_SIG (sig)) /* direct key signature */ { rc = check_signature_metadata_validity (pk, sig, r_expired, NULL); if (! rc) rc = check_signature_over_key_or_uid (ctrl, pk, sig, root, root->pkt, is_selfsig, ret_pk); } else if (IS_UID_SIG (sig) || IS_UID_REV (sig)) { kbnode_t unode = find_prev_kbnode (root, node, PKT_USER_ID); if (unode) { rc = check_signature_metadata_validity (pk, sig, r_expired, NULL); if (! rc) { /* If this is a self-sig, ignore check_pk. */ rc = check_signature_over_key_or_uid (ctrl, keyid_cmp (pk_keyid (pk), sig->keyid) == 0 ? pk : check_pk, sig, root, unode->pkt, NULL, ret_pk); } } else { if (!opt.quiet) log_info ("key %s: no user ID for key signature packet" " of class %02x\n",keystr_from_pk(pk),sig->sig_class); rc = GPG_ERR_SIG_CLASS; } } else { log_info ("sig issued by %s with class %d (digest: %02x %02x)" " is not valid over a user id or a key id, ignoring.\n", keystr (sig->keyid), sig->sig_class, sig->digest_start[0], sig->digest_start[1]); rc = gpg_error (GPG_ERR_BAD_SIGNATURE); } cache_sig_result (sig, rc); return rc; } diff --git a/g10/sign.c b/g10/sign.c index 90466e9bc..e5a3b0a29 100644 --- a/g10/sign.c +++ b/g10/sign.c @@ -1,1932 +1,1932 @@ /* sign.c - sign data * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, * 2007, 2010, 2012 Free Software Foundation, Inc. * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include #include #include #include #include #include "gpg.h" #include "options.h" #include "packet.h" #include "../common/status.h" #include "../common/iobuf.h" #include "keydb.h" #include "../common/util.h" #include "main.h" #include "filter.h" #include "../common/ttyio.h" #include "trustdb.h" #include "../common/status.h" #include "../common/i18n.h" #include "pkglue.h" #include "../common/sysutils.h" #include "call-agent.h" #include "../common/mbox-util.h" #include "../common/compliance.h" #ifdef HAVE_DOSISH_SYSTEM #define LF "\r\n" #else #define LF "\n" #endif /* Bitflags to convey hints on what kind of signayire is created. */ #define SIGNHINT_KEYSIG 1 #define SIGNHINT_SELFSIG 2 /* Hack */ static int recipient_digest_algo; /* A type for the extra data we hash into v5 signature packets. */ struct pt_extra_hash_data_s { unsigned char mode; u32 timestamp; unsigned char namelen; char name[1]; }; typedef struct pt_extra_hash_data_s *pt_extra_hash_data_t; /* * Create notations and other stuff. It is assumed that the strings in * STRLIST are already checked to contain only printable data and have * a valid NAME=VALUE format. */ static void mk_notation_policy_etc (ctrl_t ctrl, PKT_signature *sig, PKT_public_key *pk, PKT_public_key *pksk) { const char *string; char *p = NULL; strlist_t pu = NULL; struct notation *nd = NULL; struct expando_args args; log_assert (sig->version >= 4); memset (&args, 0, sizeof(args)); args.pk = pk; args.pksk = pksk; /* Notation data. */ if (IS_ATTST_SIGS(sig)) ; else if (IS_SIG(sig) && opt.sig_notations) nd = opt.sig_notations; else if (IS_CERT(sig) && opt.cert_notations) nd = opt.cert_notations; if (nd) { struct notation *item; for (item = nd; item; item = item->next) { item->altvalue = pct_expando (ctrl, item->value,&args); if (!item->altvalue) log_error (_("WARNING: unable to %%-expand notation " "(too large). Using unexpanded.\n")); } keygen_add_notations (sig, nd); for (item = nd; item; item = item->next) { xfree (item->altvalue); item->altvalue = NULL; } } /* Set policy URL. */ if (IS_ATTST_SIGS(sig)) ; else if (IS_SIG(sig) && opt.sig_policy_url) pu = opt.sig_policy_url; else if (IS_CERT(sig) && opt.cert_policy_url) pu = opt.cert_policy_url; for (; pu; pu = pu->next) { string = pu->d; p = pct_expando (ctrl, string, &args); if (!p) { log_error(_("WARNING: unable to %%-expand policy URL " "(too large). Using unexpanded.\n")); p = xstrdup(string); } build_sig_subpkt (sig, (SIGSUBPKT_POLICY | ((pu->flags & 1)?SIGSUBPKT_FLAG_CRITICAL:0)), p, strlen (p)); xfree (p); } /* Preferred keyserver URL. */ if (IS_SIG(sig) && opt.sig_keyserver_url) pu = opt.sig_keyserver_url; for (; pu; pu = pu->next) { string = pu->d; p = pct_expando (ctrl, string, &args); if (!p) { log_error (_("WARNING: unable to %%-expand preferred keyserver URL" " (too large). Using unexpanded.\n")); p = xstrdup (string); } build_sig_subpkt (sig, (SIGSUBPKT_PREF_KS | ((pu->flags & 1)?SIGSUBPKT_FLAG_CRITICAL:0)), p, strlen (p)); xfree (p); } /* Set signer's user id. */ if (IS_SIG (sig) && !opt.flags.disable_signer_uid) { char *mbox; /* For now we use the uid which was used to locate the key. */ if (pksk->user_id && (mbox = mailbox_from_userid (pksk->user_id->name, 0))) { if (DBG_LOOKUP) log_debug ("setting Signer's UID to '%s'\n", mbox); build_sig_subpkt (sig, SIGSUBPKT_SIGNERS_UID, mbox, strlen (mbox)); xfree (mbox); } else if (opt.sender_list) { /* If a list of --sender was given we scan that list and use * the first one matching a user id of the current key. */ /* FIXME: We need to get the list of user ids for the PKSK * packet. That requires either a function to look it up * again or we need to extend the key packet struct to link * to the primary key which in turn could link to the user * ids. Too much of a change right now. Let's take just * one from the supplied list and hope that the caller * passed a matching one. */ build_sig_subpkt (sig, SIGSUBPKT_SIGNERS_UID, opt.sender_list->d, strlen (opt.sender_list->d)); } } } /* - * Put the Key Block subpakcet into SIG for key PKSK. Returns an + * Put the Key Block subpacket into SIG for key PKSK. Returns an * error code on failure. */ static gpg_error_t mk_sig_subpkt_key_block (ctrl_t ctrl, PKT_signature *sig, PKT_public_key *pksk) { gpg_error_t err; char *mbox; char *filterexp = NULL; int save_opt_armor = opt.armor; int save_opt_verbose = opt.verbose; char hexfpr[2*MAX_FINGERPRINT_LEN + 1]; void *data = NULL; size_t datalen; kbnode_t keyblock = NULL; push_export_filters (); opt.armor = 0; hexfingerprint (pksk, hexfpr, sizeof hexfpr); /* Get the user id so that we know which one to insert into the * key. */ if (pksk->user_id && (mbox = mailbox_from_userid (pksk->user_id->name, 0))) { if (DBG_LOOKUP) log_debug ("including key with UID '%s' (specified)\n", mbox); filterexp = xasprintf ("keep-uid= -- mbox = %s", mbox); xfree (mbox); } else if (opt.sender_list) { /* If --sender was given we use the first one from that list. */ if (DBG_LOOKUP) log_debug ("including key with UID '%s' (--sender)\n", opt.sender_list->d); filterexp = xasprintf ("keep-uid= -- mbox = %s", opt.sender_list->d); } else /* Use the primary user id. */ { if (DBG_LOOKUP) log_debug ("including key with primary UID\n"); filterexp = xstrdup ("keep-uid= primary -t"); } if (DBG_LOOKUP) log_debug ("export filter expression: %s\n", filterexp); err = parse_and_set_export_filter (filterexp); if (err) goto leave; xfree (filterexp); filterexp = xasprintf ("drop-subkey= fpr <> %s && usage !~ e", hexfpr); if (DBG_LOOKUP) log_debug ("export filter expression: %s\n", filterexp); err = parse_and_set_export_filter (filterexp); if (err) goto leave; opt.verbose = 0; err = export_pubkey_buffer (ctrl, hexfpr, EXPORT_MINIMAL|EXPORT_CLEAN, "", 1, /* Prefix with the reserved byte. */ NULL, &keyblock, &data, &datalen); opt.verbose = save_opt_verbose; if (err) { log_error ("failed to get to be included key: %s\n", gpg_strerror (err)); goto leave; } build_sig_subpkt (sig, SIGSUBPKT_KEY_BLOCK, data, datalen); leave: xfree (data); release_kbnode (keyblock); xfree (filterexp); opt.armor = save_opt_armor; pop_export_filters (); return err; } /* * Helper to hash a user ID packet. */ static void hash_uid (gcry_md_hd_t md, int sigversion, const PKT_user_id *uid) { byte buf[5]; (void)sigversion; if (uid->attrib_data) { buf[0] = 0xd1; /* Indicates an attribute packet. */ buf[1] = uid->attrib_len >> 24; /* Always use 4 length bytes. */ buf[2] = uid->attrib_len >> 16; buf[3] = uid->attrib_len >> 8; buf[4] = uid->attrib_len; } else { buf[0] = 0xb4; /* Indicates a userid packet. */ buf[1] = uid->len >> 24; /* Always use 4 length bytes. */ buf[2] = uid->len >> 16; buf[3] = uid->len >> 8; buf[4] = uid->len; } gcry_md_write( md, buf, 5 ); if (uid->attrib_data) gcry_md_write (md, uid->attrib_data, uid->attrib_len ); else gcry_md_write (md, uid->name, uid->len ); } /* * Helper to hash some parts from the signature. EXTRAHASH gives the * extra data to be hashed into v5 signatures; it may by NULL for * detached signatures. */ static void hash_sigversion_to_magic (gcry_md_hd_t md, const PKT_signature *sig, pt_extra_hash_data_t extrahash) { byte buf[10]; int i; size_t n; gcry_md_putc (md, sig->version); gcry_md_putc (md, sig->sig_class); gcry_md_putc (md, sig->pubkey_algo); gcry_md_putc (md, sig->digest_algo); if (sig->hashed) { n = sig->hashed->len; gcry_md_putc (md, (n >> 8) ); gcry_md_putc (md, n ); gcry_md_write (md, sig->hashed->data, n ); n += 6; } else { gcry_md_putc (md, 0); /* Always hash the length of the subpacket. */ gcry_md_putc (md, 0); n = 6; } /* Hash data from the literal data packet. */ if (sig->version >= 5 && (sig->sig_class == 0x00 || sig->sig_class == 0x01)) { /* - One octet content format * - File name (one octet length followed by the name) * - Four octet timestamp */ if (extrahash) { buf[0] = extrahash->mode; buf[1] = extrahash->namelen; gcry_md_write (md, buf, 2); if (extrahash->namelen) gcry_md_write (md, extrahash->name, extrahash->namelen); buf[0] = extrahash->timestamp >> 24; buf[1] = extrahash->timestamp >> 16; buf[2] = extrahash->timestamp >> 8; buf[3] = extrahash->timestamp; gcry_md_write (md, buf, 4); } else /* Detached signatures */ { memset (buf, 0, 6); gcry_md_write (md, buf, 6); } } /* Add some magic aka known as postscript. The idea was to make it * impossible to make up a document with a v3 signature and then * turn this into a v4 signature for another document. The last * hashed 5 bytes of a v4 signature should never look like a the * last 5 bytes of a v3 signature. The length can be used to parse * from the end. */ i = 0; buf[i++] = sig->version; /* Hash convention version. */ buf[i++] = 0xff; /* Not any sig type value. */ if (sig->version >= 5) { /* Note: We don't hashed any data larger than 2^32 and thus we * can always use 0 here. See also note below. */ buf[i++] = 0; buf[i++] = 0; buf[i++] = 0; buf[i++] = 0; } buf[i++] = n >> 24; /* (n is only 16 bit, so this is always 0) */ buf[i++] = n >> 16; buf[i++] = n >> 8; buf[i++] = n; gcry_md_write (md, buf, i); } /* Perform the sign operation. If CACHE_NONCE is given the agent is * advised to use that cached passphrase for the key. SIGNHINTS has * hints so that we can do some additional checks. */ static int do_sign (ctrl_t ctrl, PKT_public_key *pksk, PKT_signature *sig, gcry_md_hd_t md, int mdalgo, const char *cache_nonce, unsigned int signhints) { gpg_error_t err; byte *dp; char *hexgrip; if (pksk->timestamp > sig->timestamp ) { ulong d = pksk->timestamp - sig->timestamp; log_info (ngettext("key %s was created %lu second" " in the future (time warp or clock problem)\n", "key %s was created %lu seconds" " in the future (time warp or clock problem)\n", d), keystr_from_pk (pksk), d); if (!opt.ignore_time_conflict) return gpg_error (GPG_ERR_TIME_CONFLICT); } print_pubkey_algo_note (pksk->pubkey_algo); if (!mdalgo) mdalgo = gcry_md_get_algo (md); if ((signhints & SIGNHINT_KEYSIG) && !(signhints & SIGNHINT_SELFSIG) && mdalgo == GCRY_MD_SHA1 && !opt.flags.allow_weak_key_signatures) { /* We do not allow the creation of third-party key signatures * using SHA-1 because we also reject them when verifying. Note * that this will render dsa1024 keys unsuitable for such * keysigs and in turn the WoT. */ print_sha1_keysig_rejected_note (); err = gpg_error (GPG_ERR_DIGEST_ALGO); goto leave; } /* Check compliance. */ if (! gnupg_digest_is_allowed (opt.compliance, 1, mdalgo)) { log_error (_("digest algorithm '%s' may not be used in %s mode\n"), gcry_md_algo_name (mdalgo), gnupg_compliance_option_string (opt.compliance)); err = gpg_error (GPG_ERR_DIGEST_ALGO); goto leave; } if (! gnupg_pk_is_allowed (opt.compliance, PK_USE_SIGNING, pksk->pubkey_algo, pksk->pkey, nbits_from_pk (pksk), NULL)) { log_error (_("key %s may not be used for signing in %s mode\n"), keystr_from_pk (pksk), gnupg_compliance_option_string (opt.compliance)); err = gpg_error (GPG_ERR_PUBKEY_ALGO); goto leave; } if (!gnupg_rng_is_compliant (opt.compliance)) { err = gpg_error (GPG_ERR_FORBIDDEN); log_error (_("%s is not compliant with %s mode\n"), "RNG", gnupg_compliance_option_string (opt.compliance)); write_status_error ("random-compliance", err); goto leave; } print_digest_algo_note (mdalgo); dp = gcry_md_read (md, mdalgo); sig->digest_algo = mdalgo; sig->digest_start[0] = dp[0]; sig->digest_start[1] = dp[1]; mpi_release (sig->data[0]); sig->data[0] = NULL; mpi_release (sig->data[1]); sig->data[1] = NULL; err = hexkeygrip_from_pk (pksk, &hexgrip); if (!err) { char *desc; gcry_sexp_t s_sigval; desc = gpg_format_keydesc (ctrl, pksk, FORMAT_KEYDESC_NORMAL, 1); err = agent_pksign (NULL/*ctrl*/, cache_nonce, hexgrip, desc, pksk->keyid, pksk->main_keyid, pksk->pubkey_algo, dp, gcry_md_get_algo_dlen (mdalgo), mdalgo, &s_sigval); xfree (desc); if (err) ; else if (pksk->pubkey_algo == GCRY_PK_RSA || pksk->pubkey_algo == GCRY_PK_RSA_S) sig->data[0] = get_mpi_from_sexp (s_sigval, "s", GCRYMPI_FMT_USG); else if (openpgp_oid_is_ed25519 (pksk->pkey[0])) { sig->data[0] = get_mpi_from_sexp (s_sigval, "r", GCRYMPI_FMT_OPAQUE); sig->data[1] = get_mpi_from_sexp (s_sigval, "s", GCRYMPI_FMT_OPAQUE); } else { sig->data[0] = get_mpi_from_sexp (s_sigval, "r", GCRYMPI_FMT_USG); sig->data[1] = get_mpi_from_sexp (s_sigval, "s", GCRYMPI_FMT_USG); } gcry_sexp_release (s_sigval); } xfree (hexgrip); leave: if (err) log_error (_("signing failed: %s\n"), gpg_strerror (err)); else { if (opt.verbose) { char *ustr = get_user_id_string_native (ctrl, sig->keyid); log_info (_("%s/%s signature from: \"%s\"\n"), openpgp_pk_algo_name (pksk->pubkey_algo), openpgp_md_algo_name (sig->digest_algo), ustr); xfree (ustr); } } return err; } static int complete_sig (ctrl_t ctrl, PKT_signature *sig, PKT_public_key *pksk, gcry_md_hd_t md, const char *cache_nonce, unsigned int signhints) { int rc; /* if (!(rc = check_secret_key (pksk, 0))) */ rc = do_sign (ctrl, pksk, sig, md, 0, cache_nonce, signhints); return rc; } /* Return true if the key seems to be on a version 1 OpenPGP card. This works by asking the agent and may fail if the card has not yet been used with the agent. */ static int openpgp_card_v1_p (PKT_public_key *pk) { gpg_error_t err; int result; /* Shortcut if we are not using RSA: The v1 cards only support RSA thus there is no point in looking any further. */ if (!is_RSA (pk->pubkey_algo)) return 0; if (!pk->flags.serialno_valid) { char *hexgrip; err = hexkeygrip_from_pk (pk, &hexgrip); if (err) { log_error ("error computing a keygrip: %s\n", gpg_strerror (err)); return 0; /* Ooops. */ } xfree (pk->serialno); agent_get_keyinfo (NULL, hexgrip, &pk->serialno, NULL); xfree (hexgrip); pk->flags.serialno_valid = 1; } if (!pk->serialno) result = 0; /* Error from a past agent_get_keyinfo or no card. */ else { /* The version number of the card is included in the serialno. */ result = !strncmp (pk->serialno, "D2760001240101", 14); } return result; } static int match_dsa_hash (unsigned int qbytes) { if (qbytes <= 20) return DIGEST_ALGO_SHA1; if (qbytes <= 28) return DIGEST_ALGO_SHA224; if (qbytes <= 32) return DIGEST_ALGO_SHA256; if (qbytes <= 48) return DIGEST_ALGO_SHA384; if (qbytes <= 66 ) /* 66 corresponds to 521 (64 to 512) */ return DIGEST_ALGO_SHA512; return DEFAULT_DIGEST_ALGO; /* DEFAULT_DIGEST_ALGO will certainly fail, but it's the best wrong answer we have if a digest larger than 512 bits is requested. */ } /* First try --digest-algo. If that isn't set, see if the recipient has a preferred algorithm (which is also filtered through --personal-digest-prefs). If we're making a signature without a particular recipient (i.e. signing, rather than signing+encrypting) then take the first algorithm in --personal-digest-prefs that is usable for the pubkey algorithm. If --personal-digest-prefs isn't set, then take the OpenPGP default (i.e. SHA-1). Note that Ed25519+EdDSA takes an input of arbitrary length and thus we don't enforce any particular algorithm like we do for standard ECDSA. However, we use SHA256 as the default algorithm. Possible improvement: Use the highest-ranked usable algorithm from the signing key prefs either before or after using the personal list? */ static int hash_for (PKT_public_key *pk) { if (opt.def_digest_algo) { return opt.def_digest_algo; } else if (recipient_digest_algo) { return recipient_digest_algo; } else if (pk->pubkey_algo == PUBKEY_ALGO_EDDSA && openpgp_oid_is_ed25519 (pk->pkey[0])) { if (opt.personal_digest_prefs) return opt.personal_digest_prefs[0].value; else return DIGEST_ALGO_SHA256; } else if (pk->pubkey_algo == PUBKEY_ALGO_DSA || pk->pubkey_algo == PUBKEY_ALGO_ECDSA) { unsigned int qbytes = gcry_mpi_get_nbits (pk->pkey[1]); if (pk->pubkey_algo == PUBKEY_ALGO_ECDSA) qbytes = ecdsa_qbits_from_Q (qbytes); qbytes = qbytes/8; /* It's a DSA key, so find a hash that is the same size as q or larger. If q is 160, assume it is an old DSA key and use a 160-bit hash unless --enable-dsa2 is set, in which case act like a new DSA key that just happens to have a 160-bit q (i.e. allow truncation). If q is not 160, by definition it must be a new DSA key. */ if (opt.personal_digest_prefs) { prefitem_t *prefs; if (qbytes != 20 || opt.flags.dsa2) { for (prefs=opt.personal_digest_prefs; prefs->type; prefs++) if (gcry_md_get_algo_dlen (prefs->value) >= qbytes) return prefs->value; } else { for (prefs=opt.personal_digest_prefs; prefs->type; prefs++) if (gcry_md_get_algo_dlen (prefs->value) == qbytes) return prefs->value; } } return match_dsa_hash(qbytes); } else if (openpgp_card_v1_p (pk)) { /* The sk lives on a smartcard, and old smartcards only handle SHA-1 and RIPEMD/160. Newer smartcards (v2.0) don't have this restriction anymore. Fortunately the serial number encodes the version of the card and thus we know that this key is on a v1 card. */ if(opt.personal_digest_prefs) { prefitem_t *prefs; for (prefs=opt.personal_digest_prefs;prefs->type;prefs++) if (prefs->value==DIGEST_ALGO_SHA1 || prefs->value==DIGEST_ALGO_RMD160) return prefs->value; } return DIGEST_ALGO_SHA1; } else if (opt.personal_digest_prefs) { /* It's not DSA, so we can use whatever the first hash algorithm is in the pref list */ return opt.personal_digest_prefs[0].value; } else return DEFAULT_DIGEST_ALGO; } static void print_status_sig_created (PKT_public_key *pk, PKT_signature *sig, int what) { byte array[MAX_FINGERPRINT_LEN]; char buf[100+MAX_FINGERPRINT_LEN*2]; size_t n; snprintf (buf, sizeof buf - 2*MAX_FINGERPRINT_LEN, "%c %d %d %02x %lu ", what, sig->pubkey_algo, sig->digest_algo, sig->sig_class, (ulong)sig->timestamp ); fingerprint_from_pk (pk, array, &n); bin2hex (array, n, buf + strlen (buf)); write_status_text( STATUS_SIG_CREATED, buf ); } /* * Loop over the secret certificates in SK_LIST and build the one pass * signature packets. OpenPGP says that the data should be bracket by * the onepass-sig and signature-packet; so we build these onepass * packet here in reverse order. */ static int write_onepass_sig_packets (SK_LIST sk_list, IOBUF out, int sigclass ) { int skcount; SK_LIST sk_rover; for (skcount=0, sk_rover=sk_list; sk_rover; sk_rover = sk_rover->next) skcount++; for (; skcount; skcount--) { PKT_public_key *pk; PKT_onepass_sig *ops; PACKET pkt; int i, rc; for (i=0, sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) if (++i == skcount) break; pk = sk_rover->pk; ops = xmalloc_clear (sizeof *ops); ops->sig_class = sigclass; ops->digest_algo = hash_for (pk); ops->pubkey_algo = pk->pubkey_algo; keyid_from_pk (pk, ops->keyid); ops->last = (skcount == 1); init_packet (&pkt); pkt.pkttype = PKT_ONEPASS_SIG; pkt.pkt.onepass_sig = ops; rc = build_packet (out, &pkt); free_packet (&pkt, NULL); if (rc) { log_error ("build onepass_sig packet failed: %s\n", gpg_strerror (rc)); return rc; } } return 0; } /* * Helper to write the plaintext (literal data) packet. At * R_EXTRAHASH a malloced object with the with the extra data hashed * into v5 signatures is stored. */ static int write_plaintext_packet (iobuf_t out, iobuf_t inp, const char *fname, int ptmode, pt_extra_hash_data_t *r_extrahash) { PKT_plaintext *pt = NULL; u32 filesize; int rc = 0; if (!opt.no_literal) pt = setup_plaintext_name (fname, inp); /* Try to calculate the length of the data. */ if ( !iobuf_is_pipe_filename (fname) && *fname) { off_t tmpsize; int overflow; if (!(tmpsize = iobuf_get_filelength (inp, &overflow)) && !overflow && opt.verbose) log_info (_("WARNING: '%s' is an empty file\n"), fname); /* We can't encode the length of very large files because * OpenPGP uses only 32 bit for file sizes. So if the size of a * file is larger than 2^32 minus some bytes for packet headers, * we switch to partial length encoding. */ if (tmpsize < (IOBUF_FILELENGTH_LIMIT - 65536)) filesize = tmpsize; else filesize = 0; /* Because the text_filter modifies the length of the * data, it is not possible to know the used length * without a double read of the file - to avoid that * we simple use partial length packets. */ if (ptmode == 't' || ptmode == 'u' || ptmode == 'm') filesize = 0; } else filesize = opt.set_filesize? opt.set_filesize : 0; /* stdin */ if (!opt.no_literal) { PACKET pkt; /* Note that PT has been initialized above in no_literal mode. */ pt->timestamp = make_timestamp (); pt->mode = ptmode; pt->len = filesize; pt->new_ctb = !pt->len; pt->buf = inp; init_packet (&pkt); pkt.pkttype = PKT_PLAINTEXT; pkt.pkt.plaintext = pt; /*cfx.datalen = filesize? calc_packet_length( &pkt ) : 0;*/ if ((rc = build_packet (out, &pkt))) log_error ("build_packet(PLAINTEXT) failed: %s\n", gpg_strerror (rc) ); *r_extrahash = xtrymalloc (sizeof **r_extrahash + pt->namelen); if (!*r_extrahash) rc = gpg_error_from_syserror (); else { (*r_extrahash)->mode = pt->mode; (*r_extrahash)->timestamp = pt->timestamp; (*r_extrahash)->namelen = pt->namelen; /* Note that the last byte of NAME won't be initialized * because we don't need it. */ memcpy ((*r_extrahash)->name, pt->name, pt->namelen); } pt->buf = NULL; free_packet (&pkt, NULL); } else { byte copy_buffer[4096]; int bytes_copied; *r_extrahash = xtrymalloc (sizeof **r_extrahash); if (!*r_extrahash) { rc = gpg_error_from_syserror (); goto leave; } /* FIXME: We need to parse INP to get the to be hashed data from * it. */ (*r_extrahash)->mode = 0; (*r_extrahash)->timestamp = 0; (*r_extrahash)->namelen = 0; while ((bytes_copied = iobuf_read (inp, copy_buffer, 4096)) != -1) if ((rc = iobuf_write (out, copy_buffer, bytes_copied))) { log_error ("copying input to output failed: %s\n", gpg_strerror (rc)); break; } wipememory (copy_buffer, 4096); /* burn buffer */ } leave: return rc; } /* * Write the signatures from the SK_LIST to OUT. HASH must be a * non-finalized hash which will not be changes here. EXTRAHASH is * either NULL or the extra data tro be hashed into v5 signatures. */ static int write_signature_packets (ctrl_t ctrl, SK_LIST sk_list, IOBUF out, gcry_md_hd_t hash, pt_extra_hash_data_t extrahash, int sigclass, u32 timestamp, u32 duration, int status_letter, const char *cache_nonce) { SK_LIST sk_rover; /* Loop over the certificates with secret keys. */ for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) { PKT_public_key *pk; PKT_signature *sig; gcry_md_hd_t md; gpg_error_t err; pk = sk_rover->pk; /* Build the signature packet. */ sig = xtrycalloc (1, sizeof *sig); if (!sig) return gpg_error_from_syserror (); if (pk->version >= 5) sig->version = 5; /* Required for v5 keys. */ else sig->version = 4; /* Required. */ keyid_from_pk (pk, sig->keyid); sig->digest_algo = hash_for (pk); sig->pubkey_algo = pk->pubkey_algo; if (timestamp) sig->timestamp = timestamp; else sig->timestamp = make_timestamp(); if (duration) sig->expiredate = sig->timestamp + duration; sig->sig_class = sigclass; if (gcry_md_copy (&md, hash)) BUG (); build_sig_subpkt_from_sig (sig, pk); mk_notation_policy_etc (ctrl, sig, NULL, pk); if (opt.flags.include_key_block && IS_SIG (sig)) err = mk_sig_subpkt_key_block (ctrl, sig, pk); else err = 0; hash_sigversion_to_magic (md, sig, extrahash); gcry_md_final (md); if (!err) err = do_sign (ctrl, pk, sig, md, hash_for (pk), cache_nonce, 0); gcry_md_close (md); if (!err) { /* Write the packet. */ PACKET pkt; init_packet (&pkt); pkt.pkttype = PKT_SIGNATURE; pkt.pkt.signature = sig; err = build_packet (out, &pkt); if (!err && is_status_enabled()) print_status_sig_created (pk, sig, status_letter); free_packet (&pkt, NULL); if (err) log_error ("build signature packet failed: %s\n", gpg_strerror (err)); } else free_seckey_enc (sig); if (err) return err; } return 0; } /* * Sign the files whose names are in FILENAME. * If DETACHED has the value true, * make a detached signature. If FILENAMES->d is NULL read from stdin * and ignore the detached mode. Sign the file with all secret keys * which can be taken from LOCUSR, if this is NULL, use the default one * If ENCRYPTFLAG is true, use REMUSER (or ask if it is NULL) to encrypt the * signed data for these users. * If OUTFILE is not NULL; this file is used for output and the function * does not ask for overwrite permission; output is then always * uncompressed, non-armored and in binary mode. */ int sign_file (ctrl_t ctrl, strlist_t filenames, int detached, strlist_t locusr, int encryptflag, strlist_t remusr, const char *outfile ) { const char *fname; armor_filter_context_t *afx; compress_filter_context_t zfx; md_filter_context_t mfx; text_filter_context_t tfx; progress_filter_context_t *pfx; encrypt_filter_context_t efx; iobuf_t inp = NULL; iobuf_t out = NULL; PACKET pkt; int rc = 0; PK_LIST pk_list = NULL; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; int multifile = 0; u32 duration=0; pt_extra_hash_data_t extrahash = NULL; pfx = new_progress_context (); afx = new_armor_context (); memset (&zfx, 0, sizeof zfx); memset (&mfx, 0, sizeof mfx); memset (&efx, 0, sizeof efx); efx.ctrl = ctrl; init_packet (&pkt); if (filenames) { fname = filenames->d; multifile = !!filenames->next; } else fname = NULL; if (fname && filenames->next && (!detached || encryptflag)) log_bug ("multiple files can only be detached signed"); if (encryptflag == 2 && (rc = setup_symkey (&efx.symkey_s2k, &efx.symkey_dek))) goto leave; if (opt.ask_sig_expire && !opt.batch) duration = ask_expire_interval(1,opt.def_sig_expire); else duration = parse_expire_string(opt.def_sig_expire); /* Note: In the old non-agent version the following call used to * unprotect the secret key. This is now done on demand by the agent. */ if ((rc = build_sk_list (ctrl, locusr, &sk_list, PUBKEY_USAGE_SIG ))) goto leave; if (encryptflag && (rc = build_pk_list (ctrl, remusr, &pk_list))) goto leave; /* Prepare iobufs. */ if (multifile) /* have list of filenames */ inp = NULL; /* we do it later */ else { inp = iobuf_open(fname); if (inp && is_secured_file (iobuf_get_fd (inp))) { iobuf_close (inp); inp = NULL; gpg_err_set_errno (EPERM); } if (!inp) { rc = gpg_error_from_syserror (); log_error (_("can't open '%s': %s\n"), fname? fname: "[stdin]", strerror (errno)); goto leave; } handle_progress (pfx, inp, fname); } if (outfile) { if (is_secured_filename (outfile)) { out = NULL; gpg_err_set_errno (EPERM); } else out = iobuf_create (outfile, 0); if (!out) { rc = gpg_error_from_syserror (); log_error (_("can't create '%s': %s\n"), outfile, gpg_strerror (rc)); goto leave; } else if (opt.verbose) log_info (_("writing to '%s'\n"), outfile); } else if ((rc = open_outfile (-1, fname, opt.armor? 1 : detached? 2 : 0, 0, &out))) { goto leave; } /* Prepare to calculate the MD over the input. */ if (opt.textmode && !outfile && !multifile) { memset (&tfx, 0, sizeof tfx); iobuf_push_filter (inp, text_filter, &tfx); } if (gcry_md_open (&mfx.md, 0, 0)) BUG (); if (DBG_HASHING) gcry_md_debug (mfx.md, "sign"); /* If we're encrypting and signing, it is reasonable to pick the * hash algorithm to use out of the recipient key prefs. This is * best effort only, as in a DSA2 and smartcard world there are * cases where we cannot please everyone with a single hash (DSA2 * wants >160 and smartcards want =160). In the future this could * be more complex with different hashes for each sk, but the * current design requires a single hash for all SKs. */ if (pk_list) { if (opt.def_digest_algo) { if (!opt.expert && select_algo_from_prefs (pk_list,PREFTYPE_HASH, opt.def_digest_algo, NULL) != opt.def_digest_algo) { log_info (_("WARNING: forcing digest algorithm %s (%d)" " violates recipient preferences\n"), gcry_md_algo_name (opt.def_digest_algo), opt.def_digest_algo); } } else { int algo; int smartcard=0; union pref_hint hint; hint.digest_length = 0; /* Of course, if the recipient asks for something * unreasonable (like the wrong hash for a DSA key) then * don't do it. Check all sk's - if any are DSA or live * on a smartcard, then the hash has restrictions and we * may not be able to give the recipient what they want. * For DSA, pass a hint for the largest q we have. Note * that this means that a q>160 key will override a q=160 * key and force the use of truncation for the q=160 key. * The alternative would be to ignore the recipient prefs * completely and get a different hash for each DSA key in * hash_for(). The override behavior here is more or less * reasonable as it is under the control of the user which * keys they sign with for a given message and the fact * that the message with multiple signatures won't be * usable on an implementation that doesn't understand * DSA2 anyway. */ for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next ) { if (sk_rover->pk->pubkey_algo == PUBKEY_ALGO_DSA || sk_rover->pk->pubkey_algo == PUBKEY_ALGO_ECDSA) { int temp_hashlen = gcry_mpi_get_nbits (sk_rover->pk->pkey[1]); if (sk_rover->pk->pubkey_algo == PUBKEY_ALGO_ECDSA) temp_hashlen = ecdsa_qbits_from_Q (temp_hashlen); temp_hashlen = (temp_hashlen+7)/8; /* Pick a hash that is large enough for our largest Q */ if (hint.digest_length < temp_hashlen) hint.digest_length = temp_hashlen; } /* FIXME: need to check gpg-agent for this. */ /* else if (sk_rover->pk->is_protected */ /* && sk_rover->pk->protect.s2k.mode == 1002) */ /* smartcard = 1; */ } /* Current smartcards only do 160-bit hashes. If we have * to have a >160-bit hash, then we can't use the * recipient prefs as we'd need both =160 and >160 at the * same time and recipient prefs currently require a * single hash for all signatures. All this may well have * to change as the cards add algorithms. */ if ((!smartcard || (smartcard && hint.digest_length==20)) && ((algo = select_algo_from_prefs (pk_list, PREFTYPE_HASH, -1, &hint)) > 0)) { recipient_digest_algo = algo; } } } for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) gcry_md_enable (mfx.md, hash_for (sk_rover->pk)); if (!multifile) iobuf_push_filter (inp, md_filter, &mfx); if (detached && !encryptflag) afx->what = 2; if (opt.armor && !outfile) push_armor_filter (afx, out); if (encryptflag) { efx.pk_list = pk_list; /* fixme: set efx.cfx.datalen if known */ iobuf_push_filter (out, encrypt_filter, &efx); } if (opt.compress_algo && !outfile && !detached) { int compr_algo = opt.compress_algo; /* If not forced by user */ if (compr_algo==-1) { /* If we're not encrypting, then select_algo_from_prefs * will fail and we'll end up with the default. If we are * encrypting, select_algo_from_prefs cannot fail since * there is an assumed preference for uncompressed data. * Still, if it did fail, we'll also end up with the * default. */ if ((compr_algo = select_algo_from_prefs (pk_list, PREFTYPE_ZIP, -1, NULL)) == -1) { compr_algo = default_compress_algo(); } } else if (!opt.expert && pk_list && select_algo_from_prefs (pk_list, PREFTYPE_ZIP, compr_algo, NULL) != compr_algo) { log_info (_("WARNING: forcing compression algorithm %s (%d)" " violates recipient preferences\n"), compress_algo_to_string (compr_algo), compr_algo); } /* Algo 0 means no compression. */ if (compr_algo) push_compress_filter (out, &zfx, compr_algo); } /* Write the one-pass signature packets if needed */ if (!detached) { rc = write_onepass_sig_packets (sk_list, out, opt.textmode && !outfile ? 0x01:0x00); if (rc) goto leave; } write_status_begin_signing (mfx.md); /* Setup the inner packet. */ if (detached) { if (multifile) { strlist_t sl; if (opt.verbose) log_info (_("signing:") ); /* Must walk reverse trough this list. */ for (sl = strlist_last(filenames); sl; sl = strlist_prev( filenames, sl)) { inp = iobuf_open (sl->d); if (inp && is_secured_file (iobuf_get_fd (inp))) { iobuf_close (inp); inp = NULL; gpg_err_set_errno (EPERM); } if (!inp) { rc = gpg_error_from_syserror (); log_error (_("can't open '%s': %s\n"), sl->d, gpg_strerror (rc)); goto leave; } handle_progress (pfx, inp, sl->d); if (opt.verbose) log_printf (" '%s'", sl->d ); if (opt.textmode) { memset (&tfx, 0, sizeof tfx); iobuf_push_filter (inp, text_filter, &tfx); } iobuf_push_filter (inp, md_filter, &mfx); while (iobuf_get (inp) != -1) ; iobuf_close (inp); inp = NULL; } if (opt.verbose) log_printf ("\n"); } else { /* Read, so that the filter can calculate the digest. */ while (iobuf_get(inp) != -1) ; } } else { rc = write_plaintext_packet (out, inp, fname, (opt.textmode && !outfile) ? (opt.mimemode? 'm' : 't') : 'b', &extrahash); } /* Catch errors from above. */ if (rc) goto leave; /* Write the signatures. */ rc = write_signature_packets (ctrl, sk_list, out, mfx.md, extrahash, opt.textmode && !outfile? 0x01 : 0x00, 0, duration, detached ? 'D':'S', NULL); if (rc) goto leave; leave: if (rc) iobuf_cancel (out); else { iobuf_close (out); if (encryptflag) write_status (STATUS_END_ENCRYPTION); } iobuf_close (inp); gcry_md_close (mfx.md); release_sk_list (sk_list); release_pk_list (pk_list); recipient_digest_algo = 0; release_progress_context (pfx); release_armor_context (afx); xfree (extrahash); return rc; } /* * Make a clear signature. Note that opt.armor is not needed. */ int clearsign_file (ctrl_t ctrl, const char *fname, strlist_t locusr, const char *outfile) { armor_filter_context_t *afx; progress_filter_context_t *pfx; gcry_md_hd_t textmd = NULL; iobuf_t inp = NULL; iobuf_t out = NULL; PACKET pkt; int rc = 0; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; u32 duration = 0; pfx = new_progress_context (); afx = new_armor_context (); init_packet( &pkt ); if (opt.ask_sig_expire && !opt.batch) duration = ask_expire_interval (1, opt.def_sig_expire); else duration = parse_expire_string (opt.def_sig_expire); /* Note: In the old non-agent version the following call used to * unprotect the secret key. This is now done on demand by the agent. */ if ((rc=build_sk_list (ctrl, locusr, &sk_list, PUBKEY_USAGE_SIG))) goto leave; /* Prepare iobufs. */ inp = iobuf_open (fname); if (inp && is_secured_file (iobuf_get_fd (inp))) { iobuf_close (inp); inp = NULL; gpg_err_set_errno (EPERM); } if (!inp) { rc = gpg_error_from_syserror (); log_error (_("can't open '%s': %s\n"), fname? fname: "[stdin]", gpg_strerror (rc)); goto leave; } handle_progress (pfx, inp, fname); if (outfile) { if (is_secured_filename (outfile)) { outfile = NULL; gpg_err_set_errno (EPERM); } else out = iobuf_create (outfile, 0); if (!out) { rc = gpg_error_from_syserror (); log_error (_("can't create '%s': %s\n"), outfile, gpg_strerror (rc)); goto leave; } else if (opt.verbose) log_info (_("writing to '%s'\n"), outfile); } else if ((rc = open_outfile (-1, fname, 1, 0, &out))) { goto leave; } iobuf_writestr (out, "-----BEGIN PGP SIGNED MESSAGE-----" LF); { const char *s; int any = 0; byte hashs_seen[256]; memset (hashs_seen, 0, sizeof hashs_seen); iobuf_writestr (out, "Hash: " ); for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) { int i = hash_for (sk_rover->pk); if (!hashs_seen[ i & 0xff ]) { s = gcry_md_algo_name (i); if (s) { hashs_seen[ i & 0xff ] = 1; if (any) iobuf_put (out, ','); iobuf_writestr (out, s); any = 1; } } } log_assert (any); iobuf_writestr (out, LF); } if (opt.not_dash_escaped) iobuf_writestr (out, "NotDashEscaped: You need "GPG_NAME " to verify this message" LF); iobuf_writestr (out, LF ); if (gcry_md_open (&textmd, 0, 0)) BUG (); for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) gcry_md_enable (textmd, hash_for(sk_rover->pk)); if (DBG_HASHING) gcry_md_debug (textmd, "clearsign"); copy_clearsig_text (out, inp, textmd, !opt.not_dash_escaped, opt.escape_from); /* fixme: check for read errors */ /* Now write the armor. */ afx->what = 2; push_armor_filter (afx, out); /* Write the signatures. */ rc = write_signature_packets (ctrl, sk_list, out, textmd, NULL, 0x01, 0, duration, 'C', NULL); if (rc) goto leave; leave: if (rc) iobuf_cancel (out); else iobuf_close (out); iobuf_close (inp); gcry_md_close (textmd); release_sk_list (sk_list); release_progress_context (pfx); release_armor_context (afx); return rc; } /* * Sign and conventionally encrypt the given file. * FIXME: Far too much code is duplicated - revamp the whole file. */ int sign_symencrypt_file (ctrl_t ctrl, const char *fname, strlist_t locusr) { armor_filter_context_t *afx; progress_filter_context_t *pfx; compress_filter_context_t zfx; md_filter_context_t mfx; text_filter_context_t tfx; cipher_filter_context_t cfx; iobuf_t inp = NULL; iobuf_t out = NULL; PACKET pkt; STRING2KEY *s2k = NULL; int rc = 0; SK_LIST sk_list = NULL; SK_LIST sk_rover = NULL; int algo; u32 duration = 0; int canceled; pt_extra_hash_data_t extrahash = NULL; pfx = new_progress_context (); afx = new_armor_context (); memset (&zfx, 0, sizeof zfx); memset (&mfx, 0, sizeof mfx); memset (&tfx, 0, sizeof tfx); memset (&cfx, 0, sizeof cfx); init_packet (&pkt); if (opt.ask_sig_expire && !opt.batch) duration = ask_expire_interval (1, opt.def_sig_expire); else duration = parse_expire_string (opt.def_sig_expire); /* Note: In the old non-agent version the following call used to * unprotect the secret key. This is now done on demand by the agent. */ rc = build_sk_list (ctrl, locusr, &sk_list, PUBKEY_USAGE_SIG); if (rc) goto leave; /* Prepare iobufs. */ inp = iobuf_open (fname); if (inp && is_secured_file (iobuf_get_fd (inp))) { iobuf_close (inp); inp = NULL; gpg_err_set_errno (EPERM); } if (!inp) { rc = gpg_error_from_syserror (); log_error (_("can't open '%s': %s\n"), fname? fname: "[stdin]", gpg_strerror (rc)); goto leave; } handle_progress (pfx, inp, fname); /* Prepare key. */ s2k = xmalloc_clear (sizeof *s2k); s2k->mode = opt.s2k_mode; s2k->hash_algo = S2K_DIGEST_ALGO; algo = default_cipher_algo (); cfx.dek = passphrase_to_dek (algo, s2k, 1, 1, NULL, &canceled); if (!cfx.dek || !cfx.dek->keylen) { rc = gpg_error (canceled?GPG_ERR_CANCELED:GPG_ERR_BAD_PASSPHRASE); log_error (_("error creating passphrase: %s\n"), gpg_strerror (rc)); goto leave; } cfx.dek->use_aead = use_aead (NULL, cfx.dek->algo); if (!cfx.dek->use_aead) cfx.dek->use_mdc = !!use_mdc (NULL, cfx.dek->algo); if (!opt.quiet || !opt.batch) log_info (_("%s.%s encryption will be used\n"), openpgp_cipher_algo_name (algo), cfx.dek->use_aead? openpgp_aead_algo_name (cfx.dek->use_aead) /**/ : "CFB"); /* Now create the outfile. */ rc = open_outfile (-1, fname, opt.armor? 1:0, 0, &out); if (rc) goto leave; /* Prepare to calculate the MD over the input. */ if (opt.textmode) iobuf_push_filter (inp, text_filter, &tfx); if (gcry_md_open (&mfx.md, 0, 0)) BUG (); if (DBG_HASHING) gcry_md_debug (mfx.md, "symc-sign"); for (sk_rover = sk_list; sk_rover; sk_rover = sk_rover->next) gcry_md_enable (mfx.md, hash_for (sk_rover->pk)); iobuf_push_filter (inp, md_filter, &mfx); /* Push armor output filter */ if (opt.armor) push_armor_filter (afx, out); /* Write the symmetric key packet */ /* (current filters: armor)*/ { PKT_symkey_enc *enc = xmalloc_clear( sizeof *enc ); enc->version = 4; enc->cipher_algo = cfx.dek->algo; enc->s2k = *s2k; pkt.pkttype = PKT_SYMKEY_ENC; pkt.pkt.symkey_enc = enc; if ((rc = build_packet (out, &pkt))) log_error ("build symkey packet failed: %s\n", gpg_strerror (rc)); xfree (enc); } /* Push the encryption filter */ iobuf_push_filter (out, cfx.dek->use_aead? cipher_filter_aead /**/ : cipher_filter_cfb, &cfx); /* Push the compress filter */ if (default_compress_algo()) { if (cfx.dek && (cfx.dek->use_mdc || cfx.dek->use_aead)) zfx.new_ctb = 1; push_compress_filter (out, &zfx,default_compress_algo() ); } /* Write the one-pass signature packets */ /* (current filters: zip - encrypt - armor) */ rc = write_onepass_sig_packets (sk_list, out, opt.textmode? 0x01:0x00); if (rc) goto leave; write_status_begin_signing (mfx.md); /* Pipe data through all filters; i.e. write the signed stuff. */ /* (current filters: zip - encrypt - armor) */ rc = write_plaintext_packet (out, inp, fname, opt.textmode ? (opt.mimemode?'m':'t'):'b', &extrahash); if (rc) goto leave; /* Write the signatures. */ /* (current filters: zip - encrypt - armor) */ rc = write_signature_packets (ctrl, sk_list, out, mfx.md, extrahash, opt.textmode? 0x01 : 0x00, 0, duration, 'S', NULL); if (rc) goto leave; leave: if (rc) iobuf_cancel (out); else { iobuf_close (out); write_status (STATUS_END_ENCRYPTION); } iobuf_close (inp); release_sk_list (sk_list); gcry_md_close (mfx.md); xfree (cfx.dek); xfree (s2k); release_progress_context (pfx); release_armor_context (afx); xfree (extrahash); return rc; } /* * Create a v4 signature in *RET_SIG. * * PK is the primary key to sign (required for all sigs) * UID is the user id to sign (required for 0x10..0x13, 0x30) * SUBPK is subkey to sign (required for 0x18, 0x19, 0x28) * * PKSK is the signing key * * SIGCLASS is the type of signature to create. * * DIGEST_ALGO is the digest algorithm. If it is 0 the function * selects an appropriate one. * * TIMESTAMP is the timestamp to use for the signature. 0 means "now" * * DURATION is the amount of time (in seconds) until the signature * expires. * * This function creates the following subpackets: issuer, created, * and expire (if duration is not 0). Additional subpackets can be * added using MKSUBPKT, which is called after these subpackets are * added and before the signature is generated. OPAQUE is passed to * MKSUBPKT. */ int make_keysig_packet (ctrl_t ctrl, PKT_signature **ret_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_public_key *subpk, PKT_public_key *pksk, int sigclass, u32 timestamp, u32 duration, int (*mksubpkt)(PKT_signature *, void *), void *opaque, const char *cache_nonce) { PKT_signature *sig; int rc = 0; int sigversion; int digest_algo; gcry_md_hd_t md; u32 pk_keyid[2], pksk_keyid[2]; unsigned int signhints; log_assert ((sigclass >= 0x10 && sigclass <= 0x13) || sigclass == 0x1F || sigclass == 0x20 || sigclass == 0x18 || sigclass == 0x19 || sigclass == 0x30 || sigclass == 0x28 ); if (pksk->version >= 5) sigversion = 5; else sigversion = 4; /* Select the digest algo to use. */ if (opt.cert_digest_algo) /* Forceful override by the user. */ digest_algo = opt.cert_digest_algo; else if (pksk->pubkey_algo == PUBKEY_ALGO_DSA) /* Meet DSA requirements. */ digest_algo = match_dsa_hash (gcry_mpi_get_nbits (pksk->pkey[1])/8); else if (pksk->pubkey_algo == PUBKEY_ALGO_ECDSA /* Meet ECDSA requirements. */ || pksk->pubkey_algo == PUBKEY_ALGO_EDDSA) { if (openpgp_oid_is_ed25519 (pksk->pkey[0])) digest_algo = DIGEST_ALGO_SHA256; else digest_algo = match_dsa_hash (ecdsa_qbits_from_Q (gcry_mpi_get_nbits (pksk->pkey[1]))/8); } else /* Use the default. */ digest_algo = DEFAULT_DIGEST_ALGO; signhints = SIGNHINT_KEYSIG; keyid_from_pk (pk, pk_keyid); keyid_from_pk (pksk, pksk_keyid); if (pk_keyid[0] == pksk_keyid[0] && pk_keyid[1] == pksk_keyid[1]) signhints |= SIGNHINT_SELFSIG; if (gcry_md_open (&md, digest_algo, 0)) BUG (); /* Hash the public key certificate. */ hash_public_key (md, pk); if (sigclass == 0x18 || sigclass == 0x19 || sigclass == 0x28) { /* Hash the subkey binding/backsig/revocation. */ hash_public_key (md, subpk); } else if (sigclass != 0x1F && sigclass != 0x20) { /* Hash the user id. */ hash_uid (md, sigversion, uid); } /* Make the signature packet. */ sig = xmalloc_clear (sizeof *sig); sig->version = sigversion; sig->flags.exportable = 1; sig->flags.revocable = 1; keyid_from_pk (pksk, sig->keyid); sig->pubkey_algo = pksk->pubkey_algo; sig->digest_algo = digest_algo; sig->timestamp = timestamp? timestamp : make_timestamp (); if (duration) sig->expiredate = sig->timestamp + duration; sig->sig_class = sigclass; build_sig_subpkt_from_sig (sig, pksk); mk_notation_policy_etc (ctrl, sig, pk, pksk); /* Crucial that the call to mksubpkt comes LAST before the calls * to finalize the sig as that makes it possible for the mksubpkt * function to get a reliable pointer to the subpacket area. */ if (mksubpkt) rc = (*mksubpkt)(sig, opaque); if (!rc) { hash_sigversion_to_magic (md, sig, NULL); gcry_md_final (md); rc = complete_sig (ctrl, sig, pksk, md, cache_nonce, signhints); } gcry_md_close (md); if (rc) free_seckey_enc (sig); else *ret_sig = sig; return rc; } /* * Create a new signature packet based on an existing one. * Only user ID signatures are supported for now. * PK is the public key to work on. * PKSK is the key used to make the signature. * * TODO: Merge this with make_keysig_packet. */ gpg_error_t update_keysig_packet (ctrl_t ctrl, PKT_signature **ret_sig, PKT_signature *orig_sig, PKT_public_key *pk, PKT_user_id *uid, PKT_public_key *subpk, PKT_public_key *pksk, int (*mksubpkt)(PKT_signature *, void *), void *opaque) { PKT_signature *sig; gpg_error_t rc = 0; int digest_algo; gcry_md_hd_t md; u32 pk_keyid[2], pksk_keyid[2]; unsigned int signhints = 0; if ((!orig_sig || !pk || !pksk) || (orig_sig->sig_class >= 0x10 && orig_sig->sig_class <= 0x13 && !uid) || (orig_sig->sig_class == 0x18 && !subpk)) return GPG_ERR_GENERAL; /* Either use the override digest algo or in the normal case the * original digest algorithm. However, iff the original digest * algorithms is SHA-1 and we are in gnupg or de-vs compliance mode * we switch to SHA-256 (done by the macro). */ if (opt.cert_digest_algo) digest_algo = opt.cert_digest_algo; else if (pksk->pubkey_algo == PUBKEY_ALGO_DSA || pksk->pubkey_algo == PUBKEY_ALGO_ECDSA || pksk->pubkey_algo == PUBKEY_ALGO_EDDSA) digest_algo = orig_sig->digest_algo; else if (orig_sig->digest_algo == DIGEST_ALGO_SHA1 || orig_sig->digest_algo == DIGEST_ALGO_RMD160) digest_algo = DEFAULT_DIGEST_ALGO; else digest_algo = orig_sig->digest_algo; signhints = SIGNHINT_KEYSIG; keyid_from_pk (pk, pk_keyid); keyid_from_pk (pksk, pksk_keyid); if (pk_keyid[0] == pksk_keyid[0] && pk_keyid[1] == pksk_keyid[1]) signhints |= SIGNHINT_SELFSIG; if (gcry_md_open (&md, digest_algo, 0)) BUG (); /* Hash the public key certificate and the user id. */ hash_public_key (md, pk); if (orig_sig->sig_class == 0x18) hash_public_key (md, subpk); else hash_uid (md, orig_sig->version, uid); /* Create a new signature packet. */ sig = copy_signature (NULL, orig_sig); sig->digest_algo = digest_algo; /* We need to create a new timestamp so that new sig expiration * calculations are done correctly... */ sig->timestamp = make_timestamp(); /* ... but we won't make a timestamp earlier than the existing * one. */ { int tmout = 0; while (sig->timestamp <= orig_sig->timestamp) { if (++tmout > 5 && !opt.ignore_time_conflict) { rc = gpg_error (GPG_ERR_TIME_CONFLICT); goto leave; } gnupg_sleep (1); sig->timestamp = make_timestamp(); } } /* Note that already expired sigs will remain expired (with a * duration of 1) since build-packet.c:build_sig_subpkt_from_sig * detects this case. */ /* Put the updated timestamp into the sig. Note that this will * automagically lower any sig expiration dates to correctly * correspond to the differences in the timestamps (i.e. the * duration will shrink). */ build_sig_subpkt_from_sig (sig, pksk); if (mksubpkt) rc = (*mksubpkt)(sig, opaque); if (!rc) { hash_sigversion_to_magic (md, sig, NULL); gcry_md_final (md); rc = complete_sig (ctrl, sig, pksk, md, NULL, signhints); } leave: gcry_md_close (md); if (rc) free_seckey_enc (sig); else *ret_sig = sig; return rc; }