diff --git a/g10/tdbio.c b/g10/tdbio.c index 1e454869d..fed0cf5ab 100644 --- a/g10/tdbio.c +++ b/g10/tdbio.c @@ -1,1896 +1,1910 @@ /* tdbio.c - trust database I/O operations * Copyright (C) 1998-2002, 2012 Free Software Foundation, Inc. * Copyright (C) 1998-2015 Werner Koch * * 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 #include #include #include "gpg.h" #include "../common/status.h" #include "../common/iobuf.h" #include "../common/util.h" #include "options.h" #include "main.h" #include "../common/i18n.h" #include "trustdb.h" #include "tdbio.h" #if defined(HAVE_DOSISH_SYSTEM) && !defined(ftruncate) #define ftruncate chsize #endif #if defined(HAVE_DOSISH_SYSTEM) || defined(__CYGWIN__) #define MY_O_BINARY O_BINARY #else #define MY_O_BINARY 0 #endif /* We use ERRNO despite that the cegcc provided open/read/write functions don't set ERRNO - at least show that ERRNO does not make sense. */ #ifdef HAVE_W32CE_SYSTEM #undef strerror #define strerror(a) ("[errno not available]") #endif /* * Yes, this is a very simple implementation. We should really * use a page aligned buffer and read complete pages. * To implement a simple trannsaction system, this is sufficient. */ typedef struct cache_ctrl_struct *CACHE_CTRL; struct cache_ctrl_struct { CACHE_CTRL next; struct { unsigned used:1; unsigned dirty:1; } flags; ulong recno; char data[TRUST_RECORD_LEN]; }; /* Size of the cache. The SOFT value is the general one. While in a transaction this may not be sufficient and thus we may increase it then up to the HARD limit. */ #define MAX_CACHE_ENTRIES_SOFT 200 #define MAX_CACHE_ENTRIES_HARD 10000 /* The cache is controlled by these variables. */ static CACHE_CTRL cache_list; static int cache_entries; static int cache_is_dirty; /* An object to pass information to cmp_krec_fpr. */ struct cmp_krec_fpr_struct { int pubkey_algo; const char *fpr; int fprlen; }; /* An object used to pass information to cmp_[s]dir. */ struct cmp_xdir_struct { int pubkey_algo; u32 keyid[2]; }; /* The name of the trustdb file. */ static char *db_name; /* The handle for locking the trustdb file and a counter to record how * often this lock has been taken. That counter is required becuase * dotlock does not implemen recursive locks. */ static dotlock_t lockhandle; static unsigned int is_locked; /* The file descriptor of the trustdb. */ static int db_fd = -1; /* A flag indicating that a transaction is active. */ /* static int in_transaction; Not yet used. */ static void open_db (void); static void create_hashtable (ctrl_t ctrl, TRUSTREC *vr, int type); /* * Take a lock on the trustdb file name. I a lock file can't be * created the function terminates the process. Except for a * different return code the function does nothing if the lock has * already been taken. * * Returns: True if lock already exists, False if the lock has * actually been taken. */ static int take_write_lock (void) { int rc; if (!lockhandle) lockhandle = dotlock_create (db_name, 0); if (!lockhandle) log_fatal ( _("can't create lock for '%s'\n"), db_name ); if (!is_locked) { if (dotlock_take (lockhandle, -1) ) log_fatal ( _("can't lock '%s'\n"), db_name ); rc = 0; } else rc = 1; if (opt.lock_once) is_locked = 1; else is_locked++; return rc; } /* * Release a lock from the trustdb file unless the global option * --lock-once has been used. */ static void release_write_lock (void) { if (opt.lock_once) return; /* Don't care; here IS_LOCKED is fixed to 1. */ if (!is_locked) { log_error ("Ooops, tdbio:release_write_lock with no lock held\n"); return; } if (--is_locked) return; if (dotlock_release (lockhandle)) log_error ("Oops, tdbio:release_write_locked failed\n"); } /************************************* ************* record cache ********** *************************************/ /* * Get the data from the record cache and return a pointer into that * cache. Caller should copy the returned data. NULL is returned on * a cache miss. */ static const char * get_record_from_cache (ulong recno) { CACHE_CTRL r; for (r = cache_list; r; r = r->next) { if (r->flags.used && r->recno == recno) return r->data; } return NULL; } /* * Write a cached item back to the trustdb file. * * Returns: 0 on success or an error code. */ static int write_cache_item (CACHE_CTRL r) { gpg_error_t err; int n; if (lseek (db_fd, r->recno * TRUST_RECORD_LEN, SEEK_SET) == -1) { err = gpg_error_from_syserror (); log_error (_("trustdb rec %lu: lseek failed: %s\n"), r->recno, strerror (errno)); return err; } n = write (db_fd, r->data, TRUST_RECORD_LEN); if (n != TRUST_RECORD_LEN) { err = gpg_error_from_syserror (); log_error (_("trustdb rec %lu: write failed (n=%d): %s\n"), r->recno, n, strerror (errno) ); return err; } r->flags.dirty = 0; return 0; } /* * Put data into the cache. This function may flush * some cache entries if the cache is filled up. * * Returns: 0 on success or an error code. */ static int put_record_into_cache (ulong recno, const char *data) { CACHE_CTRL r, unused; int dirty_count = 0; int clean_count = 0; /* See whether we already cached this one. */ for (unused = NULL, r = cache_list; r; r = r->next) { if (!r->flags.used) { if (!unused) unused = r; } else if (r->recno == recno) { if (!r->flags.dirty) { /* Hmmm: should we use a copy and compare? */ if (memcmp (r->data, data, TRUST_RECORD_LEN)) { r->flags.dirty = 1; cache_is_dirty = 1; } } memcpy (r->data, data, TRUST_RECORD_LEN); return 0; } if (r->flags.used) { if (r->flags.dirty) dirty_count++; else clean_count++; } } /* Not in the cache: add a new entry. */ if (unused) { /* Reuse this entry. */ r = unused; r->flags.used = 1; r->recno = recno; memcpy (r->data, data, TRUST_RECORD_LEN); r->flags.dirty = 1; cache_is_dirty = 1; cache_entries++; return 0; } /* See whether we reached the limit. */ if (cache_entries < MAX_CACHE_ENTRIES_SOFT) { /* No: Put into cache. */ r = xmalloc (sizeof *r); r->flags.used = 1; r->recno = recno; memcpy (r->data, data, TRUST_RECORD_LEN); r->flags.dirty = 1; r->next = cache_list; cache_list = r; cache_is_dirty = 1; cache_entries++; return 0; } /* Cache is full: discard some clean entries. */ if (clean_count) { int n; /* We discard a third of the clean entries. */ n = clean_count / 3; if (!n) n = 1; for (unused = NULL, r = cache_list; r; r = r->next) { if (r->flags.used && !r->flags.dirty) { if (!unused) unused = r; r->flags.used = 0; cache_entries--; if (!--n) break; } } /* Now put into the cache. */ log_assert (unused); r = unused; r->flags.used = 1; r->recno = recno; memcpy (r->data, data, TRUST_RECORD_LEN); r->flags.dirty = 1; cache_is_dirty = 1; cache_entries++; return 0; } /* No clean entries: We have to flush some dirty entries. */ #if 0 /* Transactions are not yet used. */ if (in_transaction) { /* But we can't do this while in a transaction. Thus we * increase the cache size instead. */ if (cache_entries < MAX_CACHE_ENTRIES_HARD) { if (opt.debug && !(cache_entries % 100)) log_debug ("increasing tdbio cache size\n"); r = xmalloc (sizeof *r); r->flags.used = 1; r->recno = recno; memcpy (r->data, data, TRUST_RECORD_LEN); r->flags.dirty = 1; r->next = cache_list; cache_list = r; cache_is_dirty = 1; cache_entries++; return 0; } /* Hard limit for the cache size reached. */ log_info (_("trustdb transaction too large\n")); return GPG_ERR_RESOURCE_LIMIT; } #endif if (dirty_count) { int n; /* Discard some dirty entries. */ n = dirty_count / 5; if (!n) n = 1; take_write_lock (); for (unused = NULL, r = cache_list; r; r = r->next) { if (r->flags.used && r->flags.dirty) { int rc; rc = write_cache_item (r); if (rc) return rc; if (!unused) unused = r; r->flags.used = 0; cache_entries--; if (!--n) break; } } release_write_lock (); /* Now put into the cache. */ log_assert (unused); r = unused; r->flags.used = 1; r->recno = recno; memcpy (r->data, data, TRUST_RECORD_LEN); r->flags.dirty = 1; cache_is_dirty = 1; cache_entries++; return 0; } /* We should never reach this. */ BUG(); } /* Return true if the cache is dirty. */ int tdbio_is_dirty() { return cache_is_dirty; } /* * Flush the cache. This cannot be used while in a transaction. */ int tdbio_sync() { CACHE_CTRL r; int did_lock = 0; if( db_fd == -1 ) open_db(); #if 0 /* Transactions are not yet used. */ if( in_transaction ) log_bug("tdbio: syncing while in transaction\n"); #endif if( !cache_is_dirty ) return 0; if (!take_write_lock ()) did_lock = 1; for( r = cache_list; r; r = r->next ) { if( r->flags.used && r->flags.dirty ) { int rc = write_cache_item( r ); if( rc ) return rc; } } cache_is_dirty = 0; if (did_lock) release_write_lock (); return 0; } #if 0 /* Not yet used. */ /* * Simple transactions system: * Everything between begin_transaction and end/cancel_transaction * is not immediately written but at the time of end_transaction. * * NOTE: The transaction code is disabled in the 1.2 branch, as it is * not yet used. */ int tdbio_begin_transaction () /* Not yet used. */ { int rc; if (in_transaction) log_bug ("tdbio: nested transactions\n"); /* Flush everything out. */ rc = tdbio_sync(); if (rc) return rc; in_transaction = 1; return 0; } int tdbio_end_transaction () /* Not yet used. */ { int rc; if (!in_transaction) log_bug ("tdbio: no active transaction\n"); take_write_lock (); gnupg_block_all_signals (); in_transaction = 0; rc = tdbio_sync(); gnupg_unblock_all_signals(); release_write_lock (); return rc; } int tdbio_cancel_transaction () /* Not yet used. */ { CACHE_CTRL r; if (!in_transaction) log_bug ("tdbio: no active transaction\n"); /* Remove all dirty marked entries, so that the original ones are * read back the next time. */ if (cache_is_dirty) { for (r = cache_list; r; r = r->next) { if (r->flags.used && r->flags.dirty) { r->flags.used = 0; cache_entries--; } } cache_is_dirty = 0; } in_transaction = 0; return 0; } #endif /* Not yet used. */ /******************************************************** **************** cached I/O functions ****************** ********************************************************/ /* The cleanup handler for this module. */ static void cleanup (void) { if (is_locked) { if (!dotlock_release (lockhandle)) is_locked = 0; } } /* * Update an existing trustdb record. The caller must call * tdbio_sync. * * Returns: 0 on success or an error code. */ int tdbio_update_version_record (ctrl_t ctrl) { TRUSTREC rec; int rc; memset (&rec, 0, sizeof rec); rc = tdbio_read_record (0, &rec, RECTYPE_VER); if (!rc) { rec.r.ver.created = make_timestamp(); rec.r.ver.marginals = opt.marginals_needed; rec.r.ver.completes = opt.completes_needed; rec.r.ver.cert_depth = opt.max_cert_depth; rec.r.ver.trust_model = opt.trust_model; rec.r.ver.min_cert_level = opt.min_cert_level; rc = tdbio_write_record (ctrl, &rec); } return rc; } /* * Create and write the trustdb version record. * This is called with the writelock activ. * Returns: 0 on success or an error code. */ static int create_version_record (ctrl_t ctrl) { TRUSTREC rec; int rc; memset (&rec, 0, sizeof rec); rec.r.ver.version = 3; rec.r.ver.created = make_timestamp (); rec.r.ver.marginals = opt.marginals_needed; rec.r.ver.completes = opt.completes_needed; rec.r.ver.cert_depth = opt.max_cert_depth; if (opt.trust_model == TM_PGP || opt.trust_model == TM_CLASSIC) rec.r.ver.trust_model = opt.trust_model; else rec.r.ver.trust_model = TM_PGP; rec.r.ver.min_cert_level = opt.min_cert_level; rec.rectype = RECTYPE_VER; rec.recnum = 0; rc = tdbio_write_record (ctrl, &rec); if (!rc) tdbio_sync (); if (!rc) create_hashtable (ctrl, &rec, 0); return rc; } /* * Set the file name for the trustdb to NEW_DBNAME and if CREATE is * true create that file. If NEW_DBNAME is NULL a default name is * used, if the it does not contain a path component separator ('/') * the global GnuPG home directory is used. * * Returns: 0 on success or an error code. * * On the first call this function registers an atexit handler. * */ int tdbio_set_dbname (ctrl_t ctrl, const char *new_dbname, int create, int *r_nofile) { char *fname, *p; struct stat statbuf; static int initialized = 0; int save_slash; if (!initialized) { atexit (cleanup); initialized = 1; } *r_nofile = 0; if (!new_dbname) { fname = make_filename (gnupg_homedir (), "trustdb" EXTSEP_S GPGEXT_GPG, NULL); } else if (*new_dbname != DIRSEP_C ) { if (strchr (new_dbname, DIRSEP_C)) fname = make_filename (new_dbname, NULL); else fname = make_filename (gnupg_homedir (), new_dbname, NULL); } else { fname = xstrdup (new_dbname); } xfree (db_name); db_name = fname; /* Quick check for (likely) case where there already is a * trustdb.gpg. This check is not required in theory, but it helps * in practice avoiding costly operations of preparing and taking * the lock. */ if (!stat (fname, &statbuf) && statbuf.st_size > 0) { /* OK, we have the valid trustdb.gpg already. */ return 0; } else if (!create) { *r_nofile = 1; return 0; } /* Here comes: No valid trustdb.gpg AND CREATE==1 */ /* * Make sure the directory exists. This should be done before * acquiring the lock, which assumes the existence of the directory. */ p = strrchr (fname, DIRSEP_C); #if HAVE_W32_SYSTEM { /* Windows may either have a slash or a backslash. Take care of it. */ char *pp = strrchr (fname, '/'); if (!p || pp > p) p = pp; } #endif /*HAVE_W32_SYSTEM*/ log_assert (p); save_slash = *p; *p = 0; if (access (fname, F_OK)) { try_make_homedir (fname); if (access (fname, F_OK)) log_fatal (_("%s: directory does not exist!\n"), fname); } *p = save_slash; take_write_lock (); if (access (fname, R_OK) || stat (fname, &statbuf) || statbuf.st_size == 0) { FILE *fp; TRUSTREC rec; int rc; mode_t oldmask; #ifdef HAVE_W32CE_SYSTEM /* We know how the cegcc implementation of access works ;-). */ if (GetLastError () == ERROR_FILE_NOT_FOUND) gpg_err_set_errno (ENOENT); else gpg_err_set_errno (EIO); #endif /*HAVE_W32CE_SYSTEM*/ if (errno && errno != ENOENT) log_fatal ( _("can't access '%s': %s\n"), fname, strerror (errno)); oldmask = umask (077); if (is_secured_filename (fname)) { fp = NULL; gpg_err_set_errno (EPERM); } else fp = fopen (fname, "wb"); umask(oldmask); if (!fp) log_fatal (_("can't create '%s': %s\n"), fname, strerror (errno)); fclose (fp); db_fd = open (db_name, O_RDWR | MY_O_BINARY); if (db_fd == -1) log_fatal (_("can't open '%s': %s\n"), db_name, strerror (errno)); rc = create_version_record (ctrl); if (rc) log_fatal (_("%s: failed to create version record: %s"), fname, gpg_strerror (rc)); /* Read again to check that we are okay. */ if (tdbio_read_record (0, &rec, RECTYPE_VER)) log_fatal (_("%s: invalid trustdb created\n"), db_name); if (!opt.quiet) log_info (_("%s: trustdb created\n"), db_name); } release_write_lock (); return 0; } /* * Return the full name of the trustdb. */ const char * tdbio_get_dbname () { return db_name; } /* * Open the trustdb. This may only be called if it has not yet been * opened and after a successful call to tdbio_set_dbname. On return * the trustdb handle (DB_FD) is guaranteed to be open. */ static void open_db () { TRUSTREC rec; log_assert( db_fd == -1 ); #ifdef HAVE_W32CE_SYSTEM { DWORD prevrc = 0; wchar_t *wname = utf8_to_wchar (db_name); if (wname) { db_fd = (int)CreateFile (wname, GENERIC_READ|GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL); xfree (wname); } if (db_fd == -1) log_fatal ("can't open '%s': %d, %d\n", db_name, (int)prevrc, (int)GetLastError ()); } #else /*!HAVE_W32CE_SYSTEM*/ db_fd = open (db_name, O_RDWR | MY_O_BINARY ); if (db_fd == -1 && (errno == EACCES #ifdef EROFS || errno == EROFS #endif ) ) { /* Take care of read-only trustdbs. */ db_fd = open (db_name, O_RDONLY | MY_O_BINARY ); if (db_fd != -1 && !opt.quiet) log_info (_("Note: trustdb not writable\n")); } if ( db_fd == -1 ) log_fatal( _("can't open '%s': %s\n"), db_name, strerror(errno) ); #endif /*!HAVE_W32CE_SYSTEM*/ register_secured_file (db_name); /* Read the version record. */ if (tdbio_read_record (0, &rec, RECTYPE_VER ) ) log_fatal( _("%s: invalid trustdb\n"), db_name ); } /* * Append a new empty hashtable to the trustdb. TYPE gives the type * of the hash table. The only defined type is 0 for a trust hash. * On return the hashtable has been created, written, the version * record update, and the data flushed to the disk. On a fatal error * the function terminates the process. */ static void create_hashtable (ctrl_t ctrl, TRUSTREC *vr, int type) { TRUSTREC rec; off_t offset; ulong recnum; int i, n, rc; offset = lseek (db_fd, 0, SEEK_END); if (offset == -1) log_fatal ("trustdb: lseek to end failed: %s\n", strerror(errno)); recnum = offset / TRUST_RECORD_LEN; log_assert (recnum); /* This is will never be the first record. */ if (!type) vr->r.ver.trusthashtbl = recnum; /* Now write the records making up the hash table. */ n = (256+ITEMS_PER_HTBL_RECORD-1) / ITEMS_PER_HTBL_RECORD; for (i=0; i < n; i++, recnum++) { memset (&rec, 0, sizeof rec); rec.rectype = RECTYPE_HTBL; rec.recnum = recnum; rc = tdbio_write_record (ctrl, &rec); if (rc) log_fatal (_("%s: failed to create hashtable: %s\n"), db_name, gpg_strerror (rc)); } /* Update the version record and flush. */ rc = tdbio_write_record (ctrl, vr); if (!rc) rc = tdbio_sync (); if (rc) log_fatal (_("%s: error updating version record: %s\n"), db_name, gpg_strerror (rc)); } /* * Check whether open trustdb matches the global trust options given * for this process. On a read problem the process is terminated. * * Return: 1 for yes, 0 for no. */ int tdbio_db_matches_options() { static int yes_no = -1; if (yes_no == -1) { TRUSTREC vr; int rc; rc = tdbio_read_record (0, &vr, RECTYPE_VER); if( rc ) log_fatal( _("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc) ); yes_no = vr.r.ver.marginals == opt.marginals_needed && vr.r.ver.completes == opt.completes_needed && vr.r.ver.cert_depth == opt.max_cert_depth && vr.r.ver.trust_model == opt.trust_model && vr.r.ver.min_cert_level == opt.min_cert_level; } return yes_no; } /* * Read and return the trust model identifier from the trustdb. On a * read problem the process is terminated. */ byte tdbio_read_model (void) { TRUSTREC vr; int rc; rc = tdbio_read_record (0, &vr, RECTYPE_VER ); if (rc) log_fatal (_("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc) ); return vr.r.ver.trust_model; } /* * Read and return the nextstamp value from the trustdb. On a read * problem the process is terminated. */ ulong tdbio_read_nextcheck () { TRUSTREC vr; int rc; rc = tdbio_read_record (0, &vr, RECTYPE_VER); if (rc) log_fatal (_("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc)); return vr.r.ver.nextcheck; } /* * Write the STAMP nextstamp timestamp to the trustdb. On a read or * write problem the process is terminated. * * Return: True if the stamp actually changed. */ int tdbio_write_nextcheck (ctrl_t ctrl, ulong stamp) { TRUSTREC vr; int rc; rc = tdbio_read_record (0, &vr, RECTYPE_VER); if (rc) log_fatal (_("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc)); if (vr.r.ver.nextcheck == stamp) return 0; vr.r.ver.nextcheck = stamp; rc = tdbio_write_record (ctrl, &vr); if (rc) log_fatal (_("%s: error writing version record: %s\n"), db_name, gpg_strerror (rc)); return 1; } /* * Return the record number of the trusthash table or create one if it * does not yet exist. On a read or write problem the process is * terminated. * * Return: record number */ static ulong get_trusthashrec (ctrl_t ctrl) { static ulong trusthashtbl; /* Record number of the trust hashtable. */ (void)ctrl; if (!trusthashtbl) { TRUSTREC vr; int rc; rc = tdbio_read_record (0, &vr, RECTYPE_VER ); if (rc) log_fatal (_("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc) ); + if (!vr.r.ver.trusthashtbl) + { + /* Oops: the trustdb is corrupt because the hashtable is + * always created along with the version record. However, + * if something went initially wrong it may happen that + * there is just the version record. We try to fix it here. + * If we can't do that we return 0 - this is the version + * record and thus the actual read will detect the mismatch + * and bail out. Note that create_hashtable updates VR. */ + take_write_lock (); + if (lseek (db_fd, 0, SEEK_END) == TRUST_RECORD_LEN) + create_hashtable (ctrl, &vr, 0); + release_write_lock (); + } trusthashtbl = vr.r.ver.trusthashtbl; } return trusthashtbl; } /* * Update a hashtable in the trustdb. TABLE gives the start of the * table, KEY and KEYLEN are the key, NEWRECNUM is the record number * to insert into the table. * * Return: 0 on success or an error code. */ static int upd_hashtable (ctrl_t ctrl, ulong table, byte *key, int keylen, ulong newrecnum) { TRUSTREC lastrec, rec; ulong hashrec, item; int msb; int level = 0; int rc, i; hashrec = table; next_level: msb = key[level]; hashrec += msb / ITEMS_PER_HTBL_RECORD; rc = tdbio_read_record (hashrec, &rec, RECTYPE_HTBL); if (rc) { log_error ("upd_hashtable: read failed: %s\n", gpg_strerror (rc)); return rc; } item = rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD]; if (!item) /* Insert a new item into the hash table. */ { rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD] = newrecnum; rc = tdbio_write_record (ctrl, &rec); if (rc) { log_error ("upd_hashtable: write htbl failed: %s\n", gpg_strerror (rc)); return rc; } } else if (item != newrecnum) /* Must do an update. */ { lastrec = rec; rc = tdbio_read_record (item, &rec, 0); if (rc) { log_error ("upd_hashtable: read item failed: %s\n", gpg_strerror (rc)); return rc; } if (rec.rectype == RECTYPE_HTBL) { hashrec = item; level++; if (level >= keylen) { log_error ("hashtable has invalid indirections.\n"); return GPG_ERR_TRUSTDB; } goto next_level; } else if (rec.rectype == RECTYPE_HLST) /* Extend the list. */ { /* Check whether the key is already in this list. */ for (;;) { for (i=0; i < ITEMS_PER_HLST_RECORD; i++) { if (rec.r.hlst.rnum[i] == newrecnum) { return 0; /* Okay, already in the list. */ } } if (rec.r.hlst.next) { rc = tdbio_read_record (rec.r.hlst.next, &rec, RECTYPE_HLST); if (rc) { log_error ("upd_hashtable: read hlst failed: %s\n", gpg_strerror (rc) ); return rc; } } else break; /* key is not in the list */ } /* Find the next free entry and put it in. */ for (;;) { for (i=0; i < ITEMS_PER_HLST_RECORD; i++) { if (!rec.r.hlst.rnum[i]) { /* Empty slot found. */ rec.r.hlst.rnum[i] = newrecnum; rc = tdbio_write_record (ctrl, &rec); if (rc) log_error ("upd_hashtable: write hlst failed: %s\n", gpg_strerror (rc)); return rc; /* Done. */ } } if (rec.r.hlst.next) { /* read the next reord of the list. */ rc = tdbio_read_record (rec.r.hlst.next, &rec, RECTYPE_HLST); if (rc) { log_error ("upd_hashtable: read hlst failed: %s\n", gpg_strerror (rc)); return rc; } } else { /* Append a new record to the list. */ rec.r.hlst.next = item = tdbio_new_recnum (ctrl); rc = tdbio_write_record (ctrl, &rec); if (rc) { log_error ("upd_hashtable: write hlst failed: %s\n", gpg_strerror (rc)); return rc; } memset (&rec, 0, sizeof rec); rec.rectype = RECTYPE_HLST; rec.recnum = item; rec.r.hlst.rnum[0] = newrecnum; rc = tdbio_write_record (ctrl, &rec); if (rc) log_error ("upd_hashtable: write ext hlst failed: %s\n", gpg_strerror (rc)); return rc; /* Done. */ } } /* end loop over list slots */ } else if (rec.rectype == RECTYPE_TRUST) /* Insert a list record. */ { if (rec.recnum == newrecnum) { return 0; } item = rec.recnum; /* Save number of key record. */ memset (&rec, 0, sizeof rec); rec.rectype = RECTYPE_HLST; rec.recnum = tdbio_new_recnum (ctrl); rec.r.hlst.rnum[0] = item; /* Old key record */ rec.r.hlst.rnum[1] = newrecnum; /* and new key record */ rc = tdbio_write_record (ctrl, &rec); if (rc) { log_error( "upd_hashtable: write new hlst failed: %s\n", gpg_strerror (rc) ); return rc; } /* Update the hashtable record. */ lastrec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD] = rec.recnum; rc = tdbio_write_record (ctrl, &lastrec); if (rc) log_error ("upd_hashtable: update htbl failed: %s\n", gpg_strerror (rc)); return rc; /* Ready. */ } else { log_error ("hashtbl %lu: %lu/%d points to an invalid record %lu\n", table, hashrec, (msb % ITEMS_PER_HTBL_RECORD), item); if (opt.verbose > 1) list_trustdb (ctrl, es_stderr, NULL); return GPG_ERR_TRUSTDB; } } return 0; } /* * Drop an entry from a hashtable. TABLE gives the start of the * table, KEY and KEYLEN are the key. * * Return: 0 on success or an error code. */ static int drop_from_hashtable (ctrl_t ctrl, ulong table, byte *key, int keylen, ulong recnum) { TRUSTREC rec; ulong hashrec, item; int msb; int level = 0; int rc, i; hashrec = table; next_level: msb = key[level]; hashrec += msb / ITEMS_PER_HTBL_RECORD; rc = tdbio_read_record (hashrec, &rec, RECTYPE_HTBL ); if (rc) { log_error ("drop_from_hashtable: read failed: %s\n", gpg_strerror (rc)); return rc; } item = rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD]; if (!item) return 0; /* Not found - forget about it. */ if (item == recnum) /* Table points direct to the record. */ { rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD] = 0; rc = tdbio_write_record (ctrl, &rec); if (rc) log_error ("drop_from_hashtable: write htbl failed: %s\n", gpg_strerror (rc)); return rc; } rc = tdbio_read_record (item, &rec, 0); if (rc) { log_error ("drop_from_hashtable: read item failed: %s\n", gpg_strerror (rc)); return rc; } if (rec.rectype == RECTYPE_HTBL) { hashrec = item; level++; if (level >= keylen) { log_error ("hashtable has invalid indirections.\n"); return GPG_ERR_TRUSTDB; } goto next_level; } if (rec.rectype == RECTYPE_HLST) { for (;;) { for (i=0; i < ITEMS_PER_HLST_RECORD; i++) { if (rec.r.hlst.rnum[i] == recnum) { rec.r.hlst.rnum[i] = 0; /* Mark as free. */ rc = tdbio_write_record (ctrl, &rec); if (rc) log_error("drop_from_hashtable: write htbl failed: %s\n", gpg_strerror (rc)); return rc; } } if (rec.r.hlst.next) { rc = tdbio_read_record (rec.r.hlst.next, &rec, RECTYPE_HLST); if (rc) { log_error ("drop_from_hashtable: read hlst failed: %s\n", gpg_strerror (rc)); return rc; } } else return 0; /* Key not in table. */ } } log_error ("hashtbl %lu: %lu/%d points to wrong record %lu\n", table, hashrec, (msb % ITEMS_PER_HTBL_RECORD), item); return GPG_ERR_TRUSTDB; } /* * Lookup a record via the hashtable TABLE by (KEY,KEYLEN) and return * the result in REC. The return value of CMP() should be True if the * record is the desired one. * * Return: 0 if found, GPG_ERR_NOT_FOUND, or another error code. */ static gpg_error_t lookup_hashtable (ulong table, const byte *key, size_t keylen, int (*cmpfnc)(const void*, const TRUSTREC *), const void *cmpdata, TRUSTREC *rec ) { int rc; ulong hashrec, item; int msb; int level = 0; if (!table) { rc = gpg_error (GPG_ERR_INV_RECORD); log_error("lookup_hashtable failed: %s\n", "request for record 0"); return rc; } hashrec = table; next_level: msb = key[level]; hashrec += msb / ITEMS_PER_HTBL_RECORD; rc = tdbio_read_record (hashrec, rec, RECTYPE_HTBL); if (rc) { log_error("lookup_hashtable failed: %s\n", gpg_strerror (rc) ); return rc; } item = rec->r.htbl.item[msb % ITEMS_PER_HTBL_RECORD]; if (!item) return gpg_error (GPG_ERR_NOT_FOUND); rc = tdbio_read_record (item, rec, 0); if (rc) { log_error( "hashtable read failed: %s\n", gpg_strerror (rc) ); return rc; } if (rec->rectype == RECTYPE_HTBL) { hashrec = item; level++; if (level >= keylen) { log_error ("hashtable has invalid indirections\n"); return GPG_ERR_TRUSTDB; } goto next_level; } else if (rec->rectype == RECTYPE_HLST) { for (;;) { int i; for (i=0; i < ITEMS_PER_HLST_RECORD; i++) { if (rec->r.hlst.rnum[i]) { TRUSTREC tmp; rc = tdbio_read_record (rec->r.hlst.rnum[i], &tmp, 0); if (rc) { log_error ("lookup_hashtable: read item failed: %s\n", gpg_strerror (rc)); return rc; } if ((*cmpfnc)(cmpdata, &tmp)) { *rec = tmp; return 0; } } } if (rec->r.hlst.next) { rc = tdbio_read_record (rec->r.hlst.next, rec, RECTYPE_HLST); if (rc) { log_error ("lookup_hashtable: read hlst failed: %s\n", gpg_strerror (rc) ); return rc; } } else return gpg_error (GPG_ERR_NOT_FOUND); } } if ((*cmpfnc)(cmpdata, rec)) return 0; /* really found */ return gpg_error (GPG_ERR_NOT_FOUND); /* no: not found */ } /* * Update the trust hash table TR or create the table if it does not * exist. * * Return: 0 on success or an error code. */ static int update_trusthashtbl (ctrl_t ctrl, TRUSTREC *tr) { return upd_hashtable (ctrl, get_trusthashrec (ctrl), tr->r.trust.fingerprint, 20, tr->recnum); } /* * Dump the trustdb record REC to stream FP. */ void tdbio_dump_record (TRUSTREC *rec, estream_t fp) { int i; ulong rnum = rec->recnum; es_fprintf (fp, "rec %5lu, ", rnum); switch (rec->rectype) { case 0: es_fprintf (fp, "blank\n"); break; case RECTYPE_VER: es_fprintf (fp, "version, td=%lu, f=%lu, m/c/d=%d/%d/%d tm=%d mcl=%d nc=%lu (%s)\n", rec->r.ver.trusthashtbl, rec->r.ver.firstfree, rec->r.ver.marginals, rec->r.ver.completes, rec->r.ver.cert_depth, rec->r.ver.trust_model, rec->r.ver.min_cert_level, rec->r.ver.nextcheck, strtimestamp(rec->r.ver.nextcheck) ); break; case RECTYPE_FREE: es_fprintf (fp, "free, next=%lu\n", rec->r.free.next); break; case RECTYPE_HTBL: es_fprintf (fp, "htbl,"); for (i=0; i < ITEMS_PER_HTBL_RECORD; i++) es_fprintf (fp, " %lu", rec->r.htbl.item[i]); es_putc ('\n', fp); break; case RECTYPE_HLST: es_fprintf (fp, "hlst, next=%lu,", rec->r.hlst.next); for (i=0; i < ITEMS_PER_HLST_RECORD; i++) es_fprintf (fp, " %lu", rec->r.hlst.rnum[i]); es_putc ('\n', fp); break; case RECTYPE_TRUST: es_fprintf (fp, "trust "); for (i=0; i < 20; i++) es_fprintf (fp, "%02X", rec->r.trust.fingerprint[i]); es_fprintf (fp, ", ot=%d, d=%d, vl=%lu\n", rec->r.trust.ownertrust, rec->r.trust.depth, rec->r.trust.validlist); break; case RECTYPE_VALID: es_fprintf (fp, "valid "); for (i=0; i < 20; i++) es_fprintf(fp, "%02X", rec->r.valid.namehash[i]); es_fprintf (fp, ", v=%d, next=%lu\n", rec->r.valid.validity, rec->r.valid.next); break; default: es_fprintf (fp, "unknown type %d\n", rec->rectype ); break; } } /* * Read the record with number RECNUM into the structure REC. If * EXPECTED is not 0 reading any other record type will return an * error. * * Return: 0 on success or an error code. */ int tdbio_read_record (ulong recnum, TRUSTREC *rec, int expected) { byte readbuf[TRUST_RECORD_LEN]; const byte *buf, *p; gpg_error_t err = 0; int n, i; if (db_fd == -1) open_db (); buf = get_record_from_cache( recnum ); if (!buf) { if (lseek (db_fd, recnum * TRUST_RECORD_LEN, SEEK_SET) == -1) { err = gpg_error_from_syserror (); log_error (_("trustdb: lseek failed: %s\n"), strerror (errno)); return err; } n = read (db_fd, readbuf, TRUST_RECORD_LEN); if (!n) { return gpg_error (GPG_ERR_EOF); } else if (n != TRUST_RECORD_LEN) { err = gpg_error_from_syserror (); log_error (_("trustdb: read failed (n=%d): %s\n"), n, strerror(errno)); return err; } buf = readbuf; } rec->recnum = recnum; rec->dirty = 0; p = buf; rec->rectype = *p++; if (expected && rec->rectype != expected) { log_error ("%lu: read expected rec type %d, got %d\n", recnum, expected, rec->rectype); return gpg_error (GPG_ERR_TRUSTDB); } p++; /* Skip reserved byte. */ switch (rec->rectype) { case 0: /* unused (free) record */ break; case RECTYPE_VER: /* version record */ if (memcmp(buf+1, GPGEXT_GPG, 3)) { log_error (_("%s: not a trustdb file\n"), db_name ); err = gpg_error (GPG_ERR_TRUSTDB); } else { p += 2; /* skip "gpg" */ rec->r.ver.version = *p++; rec->r.ver.marginals = *p++; rec->r.ver.completes = *p++; rec->r.ver.cert_depth = *p++; rec->r.ver.trust_model = *p++; rec->r.ver.min_cert_level = *p++; p += 2; rec->r.ver.created = buf32_to_ulong(p); p += 4; rec->r.ver.nextcheck = buf32_to_ulong(p); p += 4; p += 4; p += 4; rec->r.ver.firstfree = buf32_to_ulong(p); p += 4; p += 4; rec->r.ver.trusthashtbl = buf32_to_ulong(p); if (recnum) { log_error( _("%s: version record with recnum %lu\n"), db_name, (ulong)recnum ); err = gpg_error (GPG_ERR_TRUSTDB); } else if (rec->r.ver.version != 3) { log_error( _("%s: invalid file version %d\n"), db_name, rec->r.ver.version ); err = gpg_error (GPG_ERR_TRUSTDB); } } break; case RECTYPE_FREE: rec->r.free.next = buf32_to_ulong(p); break; case RECTYPE_HTBL: for (i=0; i < ITEMS_PER_HTBL_RECORD; i++) { rec->r.htbl.item[i] = buf32_to_ulong(p); p += 4; } break; case RECTYPE_HLST: rec->r.hlst.next = buf32_to_ulong(p); p += 4; for (i=0; i < ITEMS_PER_HLST_RECORD; i++) { rec->r.hlst.rnum[i] = buf32_to_ulong(p); p += 4; } break; case RECTYPE_TRUST: memcpy (rec->r.trust.fingerprint, p, 20); p+=20; rec->r.trust.ownertrust = *p++; rec->r.trust.depth = *p++; rec->r.trust.min_ownertrust = *p++; p++; rec->r.trust.validlist = buf32_to_ulong(p); break; case RECTYPE_VALID: memcpy (rec->r.valid.namehash, p, 20); p+=20; rec->r.valid.validity = *p++; rec->r.valid.next = buf32_to_ulong(p); p += 4; rec->r.valid.full_count = *p++; rec->r.valid.marginal_count = *p++; break; default: log_error ("%s: invalid record type %d at recnum %lu\n", db_name, rec->rectype, (ulong)recnum); err = gpg_error (GPG_ERR_TRUSTDB); break; } return err; } /* * Write the record from the struct REC. * * Return: 0 on success or an error code. */ int tdbio_write_record (ctrl_t ctrl, TRUSTREC *rec) { byte buf[TRUST_RECORD_LEN]; byte *p; int rc = 0; int i; ulong recnum = rec->recnum; if (db_fd == -1) open_db (); memset (buf, 0, TRUST_RECORD_LEN); p = buf; *p++ = rec->rectype; p++; switch (rec->rectype) { case 0: /* unused record */ break; case RECTYPE_VER: /* version record */ if (recnum) BUG (); memcpy(p-1, GPGEXT_GPG, 3 ); p += 2; *p++ = rec->r.ver.version; *p++ = rec->r.ver.marginals; *p++ = rec->r.ver.completes; *p++ = rec->r.ver.cert_depth; *p++ = rec->r.ver.trust_model; *p++ = rec->r.ver.min_cert_level; p += 2; ulongtobuf(p, rec->r.ver.created); p += 4; ulongtobuf(p, rec->r.ver.nextcheck); p += 4; p += 4; p += 4; ulongtobuf(p, rec->r.ver.firstfree ); p += 4; p += 4; ulongtobuf(p, rec->r.ver.trusthashtbl ); p += 4; break; case RECTYPE_FREE: ulongtobuf(p, rec->r.free.next); p += 4; break; case RECTYPE_HTBL: for (i=0; i < ITEMS_PER_HTBL_RECORD; i++) { ulongtobuf( p, rec->r.htbl.item[i]); p += 4; } break; case RECTYPE_HLST: ulongtobuf( p, rec->r.hlst.next); p += 4; for (i=0; i < ITEMS_PER_HLST_RECORD; i++ ) { ulongtobuf( p, rec->r.hlst.rnum[i]); p += 4; } break; case RECTYPE_TRUST: memcpy (p, rec->r.trust.fingerprint, 20); p += 20; *p++ = rec->r.trust.ownertrust; *p++ = rec->r.trust.depth; *p++ = rec->r.trust.min_ownertrust; p++; ulongtobuf( p, rec->r.trust.validlist); p += 4; break; case RECTYPE_VALID: memcpy (p, rec->r.valid.namehash, 20); p += 20; *p++ = rec->r.valid.validity; ulongtobuf( p, rec->r.valid.next); p += 4; *p++ = rec->r.valid.full_count; *p++ = rec->r.valid.marginal_count; break; default: BUG(); } rc = put_record_into_cache (recnum, buf); if (rc) ; else if (rec->rectype == RECTYPE_TRUST) rc = update_trusthashtbl (ctrl, rec); return rc; } /* * Delete the record at record number RECNUm from the trustdb. * * Return: 0 on success or an error code. */ int tdbio_delete_record (ctrl_t ctrl, ulong recnum) { TRUSTREC vr, rec; int rc; /* Must read the record fist, so we can drop it from the hash tables */ rc = tdbio_read_record (recnum, &rec, 0); if (rc) ; else if (rec.rectype == RECTYPE_TRUST) { rc = drop_from_hashtable (ctrl, get_trusthashrec (ctrl), rec.r.trust.fingerprint, 20, rec.recnum); } if (rc) return rc; /* Now we can change it to a free record. */ rc = tdbio_read_record (0, &vr, RECTYPE_VER); if (rc) log_fatal (_("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc)); rec.recnum = recnum; rec.rectype = RECTYPE_FREE; rec.r.free.next = vr.r.ver.firstfree; vr.r.ver.firstfree = recnum; rc = tdbio_write_record (ctrl, &rec); if (!rc) rc = tdbio_write_record (ctrl, &vr); return rc; } /* * Create a new record and return its record number. */ ulong tdbio_new_recnum (ctrl_t ctrl) { off_t offset; ulong recnum; TRUSTREC vr, rec; int rc; /* Look for unused records. */ rc = tdbio_read_record (0, &vr, RECTYPE_VER); if (rc) log_fatal( _("%s: error reading version record: %s\n"), db_name, gpg_strerror (rc)); if (vr.r.ver.firstfree) { recnum = vr.r.ver.firstfree; rc = tdbio_read_record (recnum, &rec, RECTYPE_FREE); if (rc) log_fatal (_("%s: error reading free record: %s\n"), db_name, gpg_strerror (rc)); /* Update dir record. */ vr.r.ver.firstfree = rec.r.free.next; rc = tdbio_write_record (ctrl, &vr); if (rc) log_fatal (_("%s: error writing dir record: %s\n"), db_name, gpg_strerror (rc)); /* Zero out the new record. */ memset (&rec, 0, sizeof rec); rec.rectype = 0; /* Mark as unused record (actually already done my the memset). */ rec.recnum = recnum; rc = tdbio_write_record (ctrl, &rec); if (rc) log_fatal (_("%s: failed to zero a record: %s\n"), db_name, gpg_strerror (rc)); } else /* Not found - append a new record. */ { offset = lseek (db_fd, 0, SEEK_END); if (offset == (off_t)(-1)) log_fatal ("trustdb: lseek to end failed: %s\n", strerror (errno)); recnum = offset / TRUST_RECORD_LEN; log_assert (recnum); /* This will never be the first record */ /* We must write a record, so that the next call to this * function returns another recnum. */ memset (&rec, 0, sizeof rec); rec.rectype = 0; /* unused record */ rec.recnum = recnum; rc = 0; if (lseek( db_fd, recnum * TRUST_RECORD_LEN, SEEK_SET) == -1) { rc = gpg_error_from_syserror (); log_error (_("trustdb rec %lu: lseek failed: %s\n"), recnum, strerror (errno)); } else { int n; n = write (db_fd, &rec, TRUST_RECORD_LEN); if (n != TRUST_RECORD_LEN) { rc = gpg_error_from_syserror (); log_error (_("trustdb rec %lu: write failed (n=%d): %s\n"), recnum, n, gpg_strerror (rc)); } } if (rc) log_fatal (_("%s: failed to append a record: %s\n"), db_name, gpg_strerror (rc)); } return recnum ; } /* Helper function for tdbio_search_trust_byfpr. */ static int cmp_trec_fpr ( const void *fpr, const TRUSTREC *rec ) { return (rec->rectype == RECTYPE_TRUST && !memcmp (rec->r.trust.fingerprint, fpr, 20)); } /* * Given a 20 byte FINGERPRINT search its trust record and return * that at REC. * * Return: 0 if found, GPG_ERR_NOT_FOUND, or another error code. */ gpg_error_t tdbio_search_trust_byfpr (ctrl_t ctrl, const byte *fingerprint, TRUSTREC *rec) { int rc; /* Locate the trust record using the hash table */ rc = lookup_hashtable (get_trusthashrec (ctrl), fingerprint, 20, cmp_trec_fpr, fingerprint, rec ); return rc; } /* * Given a primary public key object PK search its trust record and * return that at REC. * * Return: 0 if found, GPG_ERR_NOT_FOUND, or another error code. */ gpg_error_t tdbio_search_trust_bypk (ctrl_t ctrl, PKT_public_key *pk, TRUSTREC *rec) { byte fingerprint[MAX_FINGERPRINT_LEN]; size_t fingerlen; fingerprint_from_pk( pk, fingerprint, &fingerlen ); for (; fingerlen < 20; fingerlen++) fingerprint[fingerlen] = 0; return tdbio_search_trust_byfpr (ctrl, fingerprint, rec); } /* * Terminate the process with a message about a corrupted trustdb. */ void tdbio_invalid (void) { log_error (_("Error: The trustdb is corrupted.\n")); how_to_fix_the_trustdb (); g10_exit (2); }