diff --git a/g10/main.h b/g10/main.h
index 863afa9e0..f7c47e91f 100644
--- a/g10/main.h
+++ b/g10/main.h
@@ -1,447 +1,460 @@
/* main.h
* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
* 2008, 2009, 2010 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 .
*/
#ifndef G10_MAIN_H
#define G10_MAIN_H
#include "types.h"
#include "iobuf.h"
#include "keydb.h"
#include "util.h"
/* It could be argued that the default cipher should be 3DES rather
than AES128, and the default compression should be 0
(i.e. uncompressed) rather than 1 (zip). However, the real world
issues of speed and size come into play here. */
#if GPG_USE_AES128
# define DEFAULT_CIPHER_ALGO CIPHER_ALGO_AES
#elif GPG_USE_CAST5
# define DEFAULT_CIPHER_ALGO CIPHER_ALGO_CAST5
#else
# define DEFAULT_CIPHER_ALGO CIPHER_ALGO_3DES
#endif
#define DEFAULT_DIGEST_ALGO ((GNUPG)? DIGEST_ALGO_SHA256:DIGEST_ALGO_SHA1)
#define DEFAULT_S2K_DIGEST_ALGO DIGEST_ALGO_SHA1
#ifdef HAVE_ZIP
# define DEFAULT_COMPRESS_ALGO COMPRESS_ALGO_ZIP
#else
# define DEFAULT_COMPRESS_ALGO COMPRESS_ALGO_NONE
#endif
#define S2K_DIGEST_ALGO (opt.s2k_digest_algo?opt.s2k_digest_algo:DEFAULT_S2K_DIGEST_ALGO)
/* Various data objects. */
typedef struct
{
int header_okay;
PK_LIST pk_list;
DEK *symkey_dek;
STRING2KEY *symkey_s2k;
cipher_filter_context_t cfx;
} encrypt_filter_context_t;
struct groupitem
{
char *name;
strlist_t values;
struct groupitem *next;
};
struct weakhash
{
enum gcry_md_algos algo;
int rejection_shown;
struct weakhash *next;
};
/*-- gpg.c --*/
extern int g10_errors_seen;
#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5 )
void g10_exit(int rc) __attribute__ ((noreturn));
#else
void g10_exit(int rc);
#endif
void print_pubkey_algo_note (pubkey_algo_t algo);
void print_cipher_algo_note (cipher_algo_t algo);
void print_digest_algo_note (digest_algo_t algo);
void print_digest_rejected_note (enum gcry_md_algos algo);
void print_reported_error (gpg_error_t err, gpg_err_code_t skip_if_ec);
void print_further_info (const char *format, ...) GPGRT_ATTR_PRINTF(1,2);
void additional_weak_digest (const char* digestname);
/*-- armor.c --*/
char *make_radix64_string( const byte *data, size_t len );
/*-- misc.c --*/
void trap_unaligned(void);
int disable_core_dumps(void);
void register_secured_file (const char *fname);
void unregister_secured_file (const char *fname);
int is_secured_file (int fd);
int is_secured_filename (const char *fname);
u16 checksum_u16( unsigned n );
u16 checksum( byte *p, unsigned n );
u16 checksum_mpi( gcry_mpi_t a );
u32 buffer_to_u32( const byte *buffer );
const byte *get_session_marker( size_t *rlen );
enum gcry_cipher_algos map_cipher_openpgp_to_gcry (cipher_algo_t algo);
#define openpgp_cipher_open(_a,_b,_c,_d) \
gcry_cipher_open((_a),map_cipher_openpgp_to_gcry((_b)),(_c),(_d))
#define openpgp_cipher_get_algo_keylen(_a) \
gcry_cipher_get_algo_keylen(map_cipher_openpgp_to_gcry((_a)))
#define openpgp_cipher_get_algo_blklen(_a) \
gcry_cipher_get_algo_blklen(map_cipher_openpgp_to_gcry((_a)))
int openpgp_cipher_blocklen (cipher_algo_t algo);
int openpgp_cipher_test_algo(cipher_algo_t algo);
const char *openpgp_cipher_algo_name (cipher_algo_t algo);
pubkey_algo_t map_pk_gcry_to_openpgp (enum gcry_pk_algos algo);
int openpgp_pk_test_algo (pubkey_algo_t algo);
int openpgp_pk_test_algo2 (pubkey_algo_t algo, unsigned int use);
int openpgp_pk_algo_usage ( int algo );
const char *openpgp_pk_algo_name (pubkey_algo_t algo);
enum gcry_md_algos map_md_openpgp_to_gcry (digest_algo_t algo);
int openpgp_md_test_algo (digest_algo_t algo);
const char *openpgp_md_algo_name (int algo);
struct expando_args
{
PKT_public_key *pk;
PKT_public_key *pksk;
byte imagetype;
int validity_info;
const char *validity_string;
const byte *namehash;
};
char *pct_expando(const char *string,struct expando_args *args);
void deprecated_warning(const char *configname,unsigned int configlineno,
const char *option,const char *repl1,const char *repl2);
void deprecated_command (const char *name);
void obsolete_scdaemon_option (const char *configname,
unsigned int configlineno, const char *name);
int string_to_cipher_algo (const char *string);
int string_to_digest_algo (const char *string);
const char *compress_algo_to_string(int algo);
int string_to_compress_algo(const char *string);
int check_compress_algo(int algo);
int default_cipher_algo(void);
int default_compress_algo(void);
const char *compliance_option_string(void);
void compliance_failure(void);
struct parse_options
{
char *name;
unsigned int bit;
char **value;
char *help;
};
char *optsep(char **stringp);
char *argsplit(char *string);
int parse_options(char *str,unsigned int *options,
struct parse_options *opts,int noisy);
const char *get_libexecdir (void);
int path_access(const char *file,int mode);
int pubkey_get_npkey (pubkey_algo_t algo);
int pubkey_get_nskey (pubkey_algo_t algo);
int pubkey_get_nsig (pubkey_algo_t algo);
int pubkey_get_nenc (pubkey_algo_t algo);
/* Temporary helpers. */
unsigned int pubkey_nbits( int algo, gcry_mpi_t *pkey );
int mpi_print (estream_t stream, gcry_mpi_t a, int mode);
unsigned int ecdsa_qbits_from_Q (unsigned int qbits);
/*-- cpr.c --*/
void set_status_fd ( int fd );
int is_status_enabled ( void );
void write_status ( int no );
void write_status_error (const char *where, gpg_error_t err);
void write_status_errcode (const char *where, int errcode);
void write_status_failure (const char *where, gpg_error_t err);
void write_status_text ( int no, const char *text );
void write_status_strings (int no, const char *text,
...) GPGRT_ATTR_SENTINEL(0);
void write_status_buffer ( int no,
const char *buffer, size_t len, int wrap );
void write_status_text_and_buffer ( int no, const char *text,
const char *buffer, size_t len, int wrap );
void write_status_begin_signing (gcry_md_hd_t md);
int cpr_enabled(void);
char *cpr_get( const char *keyword, const char *prompt );
char *cpr_get_no_help( const char *keyword, const char *prompt );
char *cpr_get_utf8( const char *keyword, const char *prompt );
char *cpr_get_hidden( const char *keyword, const char *prompt );
void cpr_kill_prompt(void);
int cpr_get_answer_is_yes_def (const char *keyword, const char *prompt,
int def_yes);
int cpr_get_answer_is_yes( const char *keyword, const char *prompt );
int cpr_get_answer_yes_no_quit( const char *keyword, const char *prompt );
int cpr_get_answer_okay_cancel (const char *keyword,
const char *prompt,
int def_answer);
/*-- helptext.c --*/
void display_online_help( const char *keyword );
/*-- encode.c --*/
int setup_symkey (STRING2KEY **symkey_s2k,DEK **symkey_dek);
int use_mdc (pk_list_t pk_list,int algo);
int encrypt_symmetric (const char *filename );
int encrypt_store (const char *filename );
int encrypt_crypt (ctrl_t ctrl, int filefd, const char *filename,
strlist_t remusr, int use_symkey, pk_list_t provided_keys,
int outputfd);
void encrypt_crypt_files (ctrl_t ctrl,
int nfiles, char **files, strlist_t remusr);
int encrypt_filter (void *opaque, int control,
iobuf_t a, byte *buf, size_t *ret_len);
/*-- sign.c --*/
int complete_sig (PKT_signature *sig, PKT_public_key *pksk, gcry_md_hd_t md,
const char *cache_nonce);
int sign_file (ctrl_t ctrl, strlist_t filenames, int detached, strlist_t locusr,
int do_encrypt, strlist_t remusr, const char *outfile );
int clearsign_file (ctrl_t ctrl,
const char *fname, strlist_t locusr, const char *outfile);
int sign_symencrypt_file (ctrl_t ctrl, const char *fname, strlist_t locusr);
/*-- sig-check.c --*/
/* SIG is a revocation signature. Check if any of PK's designated
revokers generated it. If so, return 0. Note: this function
(correctly) doesn't care if the designated revoker is revoked. */
int check_revocation_keys (PKT_public_key *pk, PKT_signature *sig);
/* Check that the backsig BACKSIG from the subkey SUB_PK to its
primary key MAIN_PK is valid. */
int check_backsig(PKT_public_key *main_pk,PKT_public_key *sub_pk,
PKT_signature *backsig);
/* Check that the signature SIG over a key (e.g., a key binding or a
key revocation) is valid. (To check signatures over data, use
check_signature.) */
int check_key_signature( KBNODE root, KBNODE sig, int *is_selfsig );
/* Like check_key_signature, but with the ability to specify some
additional parameters and get back additional information. See the
documentation for the implementation for details. */
int check_key_signature2( KBNODE root, KBNODE node, PKT_public_key *check_pk,
PKT_public_key *ret_pk, int *is_selfsig,
u32 *r_expiredate, int *r_expired );
+/* 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. If SIGNER is NULL, it is looked up based on the information in
+ SIG. If not NULL, sets *IS_SELFSIG to indicate whether the
+ signature is a self-signature and *RET_PK to a copy of the signer's
+ key. */
+gpg_error_t check_signature_over_key_or_uid (PKT_public_key *signer,
+ PKT_signature *sig,
+ KBNODE kb, PACKET *packet,
+ int *is_selfsig,
+ PKT_public_key *ret_pk);
+
+
/*-- delkey.c --*/
gpg_error_t delete_keys (strlist_t names, int secret, int allow_both);
/*-- keyedit.c --*/
void keyedit_menu (ctrl_t ctrl, const char *username, strlist_t locusr,
strlist_t commands, int quiet, int seckey_check );
void keyedit_passwd (ctrl_t ctrl, const char *username);
void keyedit_quick_adduid (ctrl_t ctrl, const char *username,
const char *newuid);
void keyedit_quick_sign (ctrl_t ctrl, const char *fpr,
strlist_t uids, strlist_t locusr, int local);
void show_basic_key_info (KBNODE keyblock);
/*-- keygen.c --*/
u32 parse_expire_string(const char *string);
u32 ask_expire_interval(int object,const char *def_expire);
u32 ask_expiredate(void);
unsigned int ask_key_flags (int algo, int subkey, unsigned int current);
void quick_generate_keypair (ctrl_t ctrl, const char *uid);
void generate_keypair (ctrl_t ctrl, int full, const char *fname,
const char *card_serialno, int card_backup_key);
int keygen_set_std_prefs (const char *string,int personal);
PKT_user_id *keygen_get_std_prefs (void);
int keygen_add_key_expire( PKT_signature *sig, void *opaque );
int keygen_add_key_flags (PKT_signature *sig, void *opaque);
int keygen_add_std_prefs( PKT_signature *sig, void *opaque );
int keygen_upd_std_prefs( PKT_signature *sig, void *opaque );
int keygen_add_keyserver_url(PKT_signature *sig, void *opaque);
int keygen_add_notations(PKT_signature *sig,void *opaque);
int keygen_add_revkey(PKT_signature *sig, void *opaque);
gpg_error_t make_backsig (PKT_signature *sig, PKT_public_key *pk,
PKT_public_key *sub_pk, PKT_public_key *sub_psk,
u32 timestamp, const char *cache_nonce);
gpg_error_t generate_subkeypair (ctrl_t ctrl, kbnode_t pub_keyblock);
#ifdef ENABLE_CARD_SUPPORT
gpg_error_t generate_card_subkeypair (kbnode_t pub_keyblock,
int keyno, const char *serialno);
#endif
/*-- openfile.c --*/
int overwrite_filep( const char *fname );
char *make_outfile_name( const char *iname );
char *ask_outfile_name( const char *name, size_t namelen );
int open_outfile (int inp_fd, const char *iname, int mode,
int restrictedperm, iobuf_t *a);
char *get_matching_datafile (const char *sigfilename);
iobuf_t open_sigfile (const char *sigfilename, progress_filter_context_t *pfx);
void try_make_homedir( const char *fname );
char *get_openpgp_revocdir (const char *home);
/*-- seskey.c --*/
void make_session_key( DEK *dek );
gcry_mpi_t encode_session_key( int openpgp_pk_algo, DEK *dek, unsigned nbits );
gcry_mpi_t encode_md_value (PKT_public_key *pk,
gcry_md_hd_t md, int hash_algo );
/*-- import.c --*/
struct import_stats_s;
typedef struct import_stats_s *import_stats_t;
typedef gpg_error_t (*import_screener_t)(kbnode_t keyblock, void *arg);
int parse_import_options(char *str,unsigned int *options,int noisy);
void import_keys (ctrl_t ctrl, char **fnames, int nnames,
import_stats_t stats_hd, unsigned int options);
int import_keys_stream (ctrl_t ctrl, iobuf_t inp, import_stats_t stats_hd,
unsigned char **fpr,
size_t *fpr_len, unsigned int options);
int import_keys_es_stream (ctrl_t ctrl, estream_t fp,
import_stats_t stats_handle,
unsigned char **fpr, size_t *fpr_len,
unsigned int options,
import_screener_t screener, void *screener_arg);
gpg_error_t import_old_secring (ctrl_t ctrl, const char *fname);
import_stats_t import_new_stats_handle (void);
void import_release_stats_handle (import_stats_t hd);
void import_print_stats (import_stats_t hd);
gpg_error_t transfer_secret_keys (ctrl_t ctrl, struct import_stats_s *stats,
kbnode_t sec_keyblock, int batch, int force);
int collapse_uids( KBNODE *keyblock );
/*-- export.c --*/
struct export_stats_s;
typedef struct export_stats_s *export_stats_t;
export_stats_t export_new_stats (void);
void export_release_stats (export_stats_t stats);
void export_print_stats (export_stats_t stats);
int parse_export_options(char *str,unsigned int *options,int noisy);
int export_pubkeys (ctrl_t ctrl, strlist_t users, unsigned int options,
export_stats_t stats);
int export_seckeys (ctrl_t ctrl, strlist_t users, export_stats_t stats);
int export_secsubkeys (ctrl_t ctrl, strlist_t users, export_stats_t stats);
gpg_error_t export_pubkey_buffer (ctrl_t ctrl, const char *keyspec,
unsigned int options,
export_stats_t stats,
kbnode_t *r_keyblock,
void **r_data, size_t *r_datalen);
gpg_error_t receive_seckey_from_agent (ctrl_t ctrl, gcry_cipher_hd_t cipherhd,
char **cache_nonce_addr, const char *hexgrip,
PKT_public_key *pk);
gpg_error_t export_ssh_key (ctrl_t ctrl, const char *userid);
/*-- dearmor.c --*/
int dearmor_file( const char *fname );
int enarmor_file( const char *fname );
/*-- revoke.c --*/
struct revocation_reason_info;
int gen_standard_revoke (PKT_public_key *psk, const char *cache_nonce);
int gen_revoke( const char *uname );
int gen_desig_revoke (ctrl_t ctrl, const char *uname, strlist_t locusr);
int revocation_reason_build_cb( PKT_signature *sig, void *opaque );
struct revocation_reason_info *
ask_revocation_reason( int key_rev, int cert_rev, int hint );
void release_revocation_reason_info( struct revocation_reason_info *reason );
/*-- keylist.c --*/
void public_key_list (ctrl_t ctrl, strlist_t list, int locate_mode );
void secret_key_list (ctrl_t ctrl, strlist_t list );
void print_subpackets_colon(PKT_signature *sig);
void reorder_keyblock (KBNODE keyblock);
void list_keyblock_direct (ctrl_t ctrl, kbnode_t keyblock, int secret,
int has_secret, int fpr);
void print_fingerprint (estream_t fp, PKT_public_key *pk, int mode);
void print_revokers (estream_t fp, PKT_public_key *pk);
void show_policy_url(PKT_signature *sig,int indent,int mode);
void show_keyserver_url(PKT_signature *sig,int indent,int mode);
void show_notation(PKT_signature *sig,int indent,int mode,int which);
void dump_attribs (const PKT_user_id *uid, PKT_public_key *pk);
void set_attrib_fd(int fd);
char *format_seckey_info (PKT_public_key *pk);
void print_seckey_info (PKT_public_key *pk);
void print_pubkey_info (estream_t fp, PKT_public_key *pk);
void print_card_key_info (estream_t fp, KBNODE keyblock);
/*-- verify.c --*/
void print_file_status( int status, const char *name, int what );
int verify_signatures (ctrl_t ctrl, int nfiles, char **files );
int verify_files (ctrl_t ctrl, int nfiles, char **files );
int gpg_verify (ctrl_t ctrl, int sig_fd, int data_fd, estream_t out_fp);
/*-- decrypt.c --*/
int decrypt_message (ctrl_t ctrl, const char *filename );
gpg_error_t decrypt_message_fd (ctrl_t ctrl, int input_fd, int output_fd);
void decrypt_messages (ctrl_t ctrl, int nfiles, char *files[]);
/*-- plaintext.c --*/
int hash_datafiles( gcry_md_hd_t md, gcry_md_hd_t md2,
strlist_t files, const char *sigfilename, int textmode);
int hash_datafile_by_fd ( gcry_md_hd_t md, gcry_md_hd_t md2, int data_fd,
int textmode );
PKT_plaintext *setup_plaintext_name(const char *filename,IOBUF iobuf);
/*-- server.c --*/
int gpg_server (ctrl_t);
gpg_error_t gpg_proxy_pinentry_notify (ctrl_t ctrl,
const unsigned char *line);
#ifdef ENABLE_CARD_SUPPORT
/*-- card-util.c --*/
void change_pin (int no, int allow_admin);
void card_status (estream_t fp, char *serialno, size_t serialnobuflen);
void card_edit (ctrl_t ctrl, strlist_t commands);
gpg_error_t card_generate_subkey (KBNODE pub_keyblock);
int card_store_subkey (KBNODE node, int use);
#endif
#define S2K_DECODE_COUNT(_val) ((16ul + ((_val) & 15)) << (((_val) >> 4) + 6))
/*-- migrate.c --*/
void migrate_secring (ctrl_t ctrl);
#endif /*G10_MAIN_H*/
diff --git a/g10/sig-check.c b/g10/sig-check.c
index 262afed37..4530a64c3 100644
--- a/g10/sig-check.c
+++ b/g10/sig-check.c
@@ -1,913 +1,1094 @@
/* sig-check.c - Check a signature
* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003,
* 2004, 2006 Free Software Foundation, Inc.
- * Copyright (C) 2015 g10 Code GmbH
+ * 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 "util.h"
#include "packet.h"
#include "keydb.h"
#include "main.h"
#include "status.h"
#include "i18n.h"
#include "options.h"
#include "pkglue.h"
static int check_signature_end (PKT_public_key *pk, PKT_signature *sig,
gcry_md_hd_t digest,
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);
/* Check a signature. This is shorthand for check_signature2 with
the unnamed arguments passed as NULL. */
int
check_signature (PKT_signature *sig, gcry_md_hd_t digest)
{
return check_signature2 (sig, digest, 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.")
*
* 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 PK is not NULL, the public key is saved in *PK on success.
*
* Returns 0 on success. An error code otherwise. */
int
check_signature2 (PKT_signature *sig, gcry_md_hd_t digest, u32 *r_expiredate,
int *r_expired, int *r_revoked, PKT_public_key *pk )
{
int rc=0;
int pk_internal;
if (pk)
pk_internal = 0;
else
{
pk_internal = 1;
pk = xmalloc_clear( sizeof *pk );
}
if ( (rc=openpgp_md_test_algo(sig->digest_algo)) )
; /* We don't have this digest. */
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_ERR_GENERAL;
}
else if( get_pubkey( pk, sig->keyid ) )
rc = GPG_ERR_NO_PUBKEY;
else if(!pk->flags.valid && !pk->flags.primary)
{
/* You cannot have a good sig from an invalid subkey. */
rc = GPG_ERR_BAD_PUBKEY;
}
else
{
if(r_expiredate)
*r_expiredate = pk->expiredate;
rc = check_signature_end (pk, sig, digest, r_expired, r_revoked, NULL);
/* Check the backsig. This is a 0x19 signature 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==0 && !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");
/* --require-cross-certification makes this warning an
error. TODO: change the default to require this
after more keys have backsigs. */
if(opt.flags.require_cross_cert)
rc = 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_ERR_GENERAL;
}
}
}
if (pk_internal || rc)
{
release_public_key_parts (pk);
if (pk_internal)
xfree (pk);
else
/* Be very sure that the caller doesn't try to use *PK. */
memset (pk, 0, sizeof (*pk));
}
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];
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);
}
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 ) );
sprintf(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,
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)))
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)
{
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;
}
/* 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[6];
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;
}
/* add some magic per Section 5.2.4 of RFC 4880. */
buf[0] = sig->version;
buf[1] = 0xff;
buf[2] = n >> 24;
buf[3] = n >> 16;
buf[4] = n >> 8;
buf[5] = n;
gcry_md_write( digest, buf, 6 );
}
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. */
rc = pk_verify( pk->pubkey_algo, result, sig->data, pk->pkey );
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_node( KBNODE unode, gcry_md_hd_t md, PKT_signature *sig )
+hash_uid_packet (PKT_user_id *uid, gcry_md_hd_t md, PKT_signature *sig )
{
- PKT_user_id *uid = unode->pkt->pkt.user_id;
-
- assert( unode->pkt->pkttype == PKT_USER_ID );
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 (PKT_public_key *pk, PKT_signature *sig)
{
static int busy=0;
int i;
int rc = GPG_ERR_GENERAL;
assert(IS_KEY_REV(sig));
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(pk->revkey[i].fpr,MAX_FINGERPRINT_LEN,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(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, 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 (KBNODE root, KBNODE node, int *is_selfsig)
{
return check_key_signature2 (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 (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;
+
+ 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 (/* Primary key binding (made by a subkey). */
+ sig->sig_class == 0x19
+ /* Direct key signature. */
+ || sig->sig_class == 0x1f
+ /* Primary key revocation. */
+ || sig->sig_class == 0x20)
+ {
+ if (packet->pkttype != PKT_PUBLIC_KEY)
+ /* Key revocations can only be over primary keys. */
+ return gpg_error (GPG_ERR_SIG_CLASS);
+ }
+ else if (/* Subkey binding. */
+ sig->sig_class == 0x18
+ /* Subkey revocation. */
+ || sig->sig_class == 0x28)
+ {
+ if (packet->pkttype != PKT_PUBLIC_SUBKEY)
+ return gpg_error (GPG_ERR_SIG_CLASS);
+ }
+ else if (/* Certification. */
+ sig->sig_class == 0x10
+ || sig->sig_class == 0x11
+ || sig->sig_class == 0x12
+ || sig->sig_class == 0x13
+ /* Certification revocation. */
+ || sig->sig_class == 0x30)
+ {
+ 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 (is_selfsig)
+ {
+ 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;
+ if (is_selfsig)
+ *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, PKT_PUBLIC_SUBKEY)))
+ {
+ PKT_public_key *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. */
+ {
+ if (is_selfsig)
+ *is_selfsig = 0;
+ if (ret_pk)
+ {
+ signer = ret_pk;
+ memset (signer, 0, sizeof (*signer));
+ signer_alloced = 1;
+ }
+ else
+ {
+ signer = xmalloc_clear (sizeof (*signer));
+ signer_alloced = 2;
+ }
+
+ rc = get_pubkey (signer, sig->keyid);
+ if (rc)
+ {
+ xfree (signer);
+ signer = NULL;
+ signer_alloced = 0;
+ goto out;
+ }
+ }
+ }
+ }
+
+ /* 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 (/* Direct key signature. */
+ sig->sig_class == 0x1f
+ /* Primary key revocation. */
+ || sig->sig_class == 0x20)
+ {
+ assert (packet->pkttype == PKT_PUBLIC_KEY);
+ hash_public_key (md, packet->pkt.public_key);
+ rc = check_signature_end_simple (signer, sig, md);
+ }
+ else if (/* Primary key binding (made by a subkey). */
+ sig->sig_class == 0x19)
+ {
+ 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);
+ }
+ else if (/* Subkey binding. */
+ sig->sig_class == 0x18
+ /* Subkey revocation. */
+ || sig->sig_class == 0x28)
+ {
+ 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);
+ }
+ else if (/* Certification. */
+ sig->sig_class == 0x10
+ || sig->sig_class == 0x11
+ || sig->sig_class == 0x12
+ || sig->sig_class == 0x13
+ /* Certification revocation. */
+ || sig->sig_class == 0x30)
+ {
+ assert (packet->pkttype == PKT_USER_ID);
+ hash_public_key (md, pripk);
+ hash_uid_packet (packet->pkt.user_id, md, sig);
+ rc = check_signature_end_simple (signer, sig, md);
+ }
+ else
+ /* We should never get here. (The first if above should have
+ already caught this error.) */
+ BUG ();
+
+ gcry_md_close (md);
+
+ out:
+ if (! rc && ret_pk && (signer_alloced == -1 || ret_pk != signer))
+ copy_public_key (ret_pk, signer);
+ if (signer_alloced == 1)
+ /* We looked up SIGNER; it is not a pointer into KB. */
+ {
+ release_public_key_parts (signer);
+ if (signer_alloced == 2)
+ /* We also allocated the memory. */
+ 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. */
int
check_key_signature2 (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 )
{
- gcry_md_hd_t md;
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;
assert (node->pkt->pkttype == PKT_SIGNATURE);
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 )
{
if (sig->flags.checked) /* Cached status available. */
{
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;
return sig->flags.valid? 0 : 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 (sig->sig_class == 0x20) /* key revocation */
{
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 (pk, sig);
else
{
- if (gcry_md_open (&md, algo, 0))
- BUG ();
- hash_public_key (md, pk);
- rc = check_signature_end (pk, sig, md, r_expired, NULL, ret_pk);
- cache_sig_result (sig, rc);
- gcry_md_close (md);
+ rc = check_signature_metadata_validity (pk, sig,
+ r_expired, NULL);
+ if (! rc)
+ rc = check_signature_over_key_or_uid (pk, sig, root, root->pkt,
+ is_selfsig, ret_pk);
}
}
- else if (sig->sig_class == 0x28) /* subkey revocation */
+ else if (sig->sig_class == 0x28 /* subkey revocation */
+ || sig->sig_class == 0x18) /* key binding */
{
kbnode_t snode = find_prev_kbnode (root, node, PKT_PUBLIC_SUBKEY);
if (snode)
{
- if (gcry_md_open (&md, algo, 0))
- BUG ();
- hash_public_key (md, pk);
- hash_public_key (md, snode->pkt->pkt.public_key);
- rc = check_signature_end (pk, sig, md, r_expired, NULL, ret_pk);
- cache_sig_result (sig, rc);
- gcry_md_close (md);
+ rc = check_signature_metadata_validity (pk, sig,
+ r_expired, NULL);
+ if (! rc)
+ /* 0x28 must be a self-sig, but 0x18 needn't be. */
+ rc = check_signature_over_key_or_uid (sig->sig_class == 0x18
+ ? NULL : pk,
+ sig, root, snode->pkt,
+ is_selfsig, ret_pk);
}
else
{
if (opt.verbose)
- log_info (_("key %s: no subkey for subkey"
- " revocation signature\n"), keystr_from_pk(pk));
+ {
+ if (sig->sig_class == 0x28)
+ 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 (sig->sig_class == 0x18) /* key binding */
- {
- kbnode_t snode = find_prev_kbnode (root, node, PKT_PUBLIC_SUBKEY);
-
- if (snode)
- {
- if (is_selfsig)
- {
- /* Does this make sense? It should always be a
- selfsig. Yes: We can't be sure about this and we
- need to be able to indicate that it is a selfsig.
- FIXME: The question is whether we should reject
- such a signature if it is not a selfsig. */
- u32 keyid[2];
-
- keyid_from_pk (pk, keyid);
- if (keyid[0] == sig->keyid[0] && keyid[1] == sig->keyid[1])
- *is_selfsig = 1;
- }
- if (gcry_md_open (&md, algo, 0))
- BUG ();
- hash_public_key (md, pk);
- hash_public_key (md, snode->pkt->pkt.public_key);
- rc = check_signature_end (pk, sig, md, r_expired, NULL, ret_pk);
- cache_sig_result ( sig, rc );
- gcry_md_close (md);
- }
- else
- {
- if (opt.verbose)
- log_info(_("key %s: no subkey for subkey"
- " binding signature\n"), keystr_from_pk(pk));
- rc = GPG_ERR_SIG_CLASS;
- }
- }
else if (sig->sig_class == 0x1f) /* direct key signature */
{
- if (gcry_md_open (&md, algo, 0 ))
- BUG ();
- hash_public_key( md, pk );
- rc = check_signature_end (pk, sig, md, r_expired, NULL, ret_pk);
- cache_sig_result (sig, rc);
- gcry_md_close (md);
+ rc = check_signature_metadata_validity (pk, sig,
+ r_expired, NULL);
+ if (! rc)
+ rc = check_signature_over_key_or_uid (pk, sig, root, root->pkt,
+ is_selfsig, ret_pk);
}
- else /* all other classes */
+ else if (/* Certification. */
+ sig->sig_class == 0x10
+ || sig->sig_class == 0x11
+ || sig->sig_class == 0x12
+ || sig->sig_class == 0x13
+ /* Certification revocation. */
+ || sig->sig_class == 0x30)
{
kbnode_t unode = find_prev_kbnode (root, node, PKT_USER_ID);
if (unode)
{
- u32 keyid[2];
-
- keyid_from_pk (pk, keyid);
- if (gcry_md_open (&md, algo, 0))
- BUG ();
- hash_public_key (md, pk);
- hash_uid_node (unode, md, sig);
- if (keyid[0] == sig->keyid[0] && keyid[1] == sig->keyid[1])
- { /* The primary key is the signing key. */
-
- if (is_selfsig)
- *is_selfsig = 1;
- rc = check_signature_end (pk, sig, md, r_expired, NULL, ret_pk);
- }
- else if (check_pk)
- { /* The caller specified a key. Try that. */
-
- rc = check_signature_end (check_pk, sig, md,
- r_expired, NULL, ret_pk);
- }
- else
- { /* Look up the key. */
- rc = check_signature2 (sig, md, r_expiredate, r_expired,
- NULL, ret_pk);
- }
-
- cache_sig_result (sig, rc);
- gcry_md_close (md);
+ 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
+ (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
+ BUG ();
+
+ cache_sig_result (sig, rc);
return rc;
}