gnupg/g10/tdbio.c

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/* tdbio.c - trust databse I/O operations
* Copyright (C) 1998, 1999, 2000, 2001, 2002 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 <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "gpg.h"
#include "status.h"
#include "iobuf.h"
#include "util.h"
#include "options.h"
#include "main.h"
#include "i18n.h"
#include "trustdb.h"
#include "tdbio.h"
#if defined(HAVE_DOSISH_SYSTEM)
#define ftruncate chsize
#endif
#if defined(HAVE_DOSISH_SYSTEM) || defined(__CYGWIN__)
#define MY_O_BINARY O_BINARY
#else
#define MY_O_BINARY 0
#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];
};
#define MAX_CACHE_ENTRIES_SOFT 200 /* may be increased while in a */
#define MAX_CACHE_ENTRIES_HARD 10000 /* transaction to this one */
static CACHE_CTRL cache_list;
static int cache_entries;
static int cache_is_dirty;
/* a type used to pass infomation to cmp_krec_fpr */
struct cmp_krec_fpr_struct {
int pubkey_algo;
const char *fpr;
int fprlen;
};
/* a type used to pass infomation to cmp_[s]dir */
struct cmp_xdir_struct {
int pubkey_algo;
u32 keyid[2];
};
static char *db_name;
static DOTLOCK lockhandle;
static int is_locked;
static int db_fd = -1;
static int in_transaction;
static void open_db(void);
/*************************************
************* record cache **********
*************************************/
/****************
* Get the data from therecord cache and return a
* pointer into that cache. Caller should copy
* the return 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;
}
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 the
* some cache entries if there is not enough space available.
*/
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 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 */
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 = clean_count / 3; /* discard a third of the clean entries */
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;
}
}
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: have to flush some dirty entries */
if( in_transaction ) {
/* but we can't do this while in a transaction
* we increase the cache size instead */
if( cache_entries < MAX_CACHE_ENTRIES_HARD ) { /* no */
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;
}
log_info(_("trustdb transaction too large\n"));
return G10ERR_RESOURCE_LIMIT;
}
if( dirty_count ) {
int n = dirty_count / 5; /* discard some dirty entries */
if( !n )
n = 1;
if( !is_locked ) {
if( make_dotlock( lockhandle, -1 ) )
log_fatal("can't acquire lock - giving up\n");
else
is_locked = 1;
}
for( unused = NULL, r = cache_list; r; r = r->next ) {
if( r->flags.used && r->flags.dirty ) {
int rc = write_cache_item( r );
if( rc )
return rc;
if( !unused )
unused = r;
r->flags.used = 0;
cache_entries--;
if( !--n )
break;
}
}
if( !opt.lock_once ) {
if( !release_dotlock( lockhandle ) )
is_locked = 0;
}
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;
}
BUG();
}
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( in_transaction )
log_bug("tdbio: syncing while in transaction\n");
if( !cache_is_dirty )
return 0;
if( !is_locked ) {
if( make_dotlock( lockhandle, -1 ) )
log_fatal("can't acquire lock - giving up\n");
else
is_locked = 1;
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 && !opt.lock_once ) {
if( !release_dotlock( lockhandle ) )
is_locked = 0;
}
return 0;
}
#if 0
/* The transaction code is disabled in the 1.2.x branch, as it is not
yet used. It will be enabled in 1.3.x. */
/****************
* Simple transactions system:
* Everything between begin_transaction and end/cancel_transaction
* is not immediatly written but at the time of end_transaction.
*
*/
int
tdbio_begin_transaction()
{
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()
{
int rc;
if( !in_transaction )
log_bug("tdbio: no active transaction\n");
if( !is_locked ) {
if( make_dotlock( lockhandle, -1 ) )
log_fatal("can't acquire lock - giving up\n");
else
is_locked = 1;
}
block_all_signals();
in_transaction = 0;
rc = tdbio_sync();
unblock_all_signals();
if( !opt.lock_once ) {
if( !release_dotlock( lockhandle ) )
is_locked = 0;
}
return rc;
}
int
tdbio_cancel_transaction()
{
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
/********************************************************
**************** cached I/O functions ******************
********************************************************/
static void
cleanup(void)
{
if( is_locked ) {
if( !release_dotlock(lockhandle) )
is_locked = 0;
}
}
/* Caller must sync */
int
tdbio_update_version_record (void)
{
TRUSTREC rec;
int rc;
memset( &rec, 0, sizeof rec );
rc=tdbio_read_record( 0, &rec, RECTYPE_VER);
if(rc==0)
{
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;
rc=tdbio_write_record(&rec);
}
return rc;
}
static int
create_version_record (void)
{
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.rectype = RECTYPE_VER;
rec.recnum = 0;
rc = tdbio_write_record( &rec );
if( !rc )
tdbio_sync();
return rc;
}
int
tdbio_set_dbname( const char *new_dbname, int create )
{
char *fname;
static int initialized = 0;
if( !initialized ) {
atexit( cleanup );
initialized = 1;
}
if(new_dbname==NULL)
fname=make_filename(opt.homedir,"trustdb" EXTSEP_S "gpg", NULL);
else if (*new_dbname != DIRSEP_C )
{
if (strchr(new_dbname, DIRSEP_C) )
fname = make_filename (new_dbname, NULL);
else
fname = make_filename (opt.homedir, new_dbname, NULL);
}
else
fname = xstrdup (new_dbname);
if( access( fname, R_OK ) ) {
if( errno != ENOENT ) {
log_error( _("can't access `%s': %s\n"), fname, strerror(errno) );
xfree(fname);
return G10ERR_TRUSTDB;
}
if( create ) {
FILE *fp;
TRUSTREC rec;
int rc;
char *p = strrchr( fname, DIRSEP_C );
mode_t oldmask;
int save_slash;
#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*/
assert (p);
save_slash = *p;
*p = 0;
if( access( fname, F_OK ) ) {
try_make_homedir( fname );
log_fatal( _("%s: directory does not exist!\n"), fname );
}
*p = save_slash;
xfree(db_name);
db_name = fname;
#ifdef __riscos__
if( !lockhandle )
lockhandle = create_dotlock( db_name );
if( !lockhandle )
log_fatal( _("can't create lock for `%s'\n"), db_name );
if( make_dotlock( lockhandle, -1 ) )
log_fatal( _("can't lock `%s'\n"), db_name );
#endif /* __riscos__ */
oldmask=umask(077);
if (is_secured_filename (fname)) {
fp = NULL;
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) );
#ifndef __riscos__
if( !lockhandle )
lockhandle = create_dotlock( db_name );
if( !lockhandle )
log_fatal( _("can't create lock for `%s'\n"), db_name );
#endif /* !__riscos__ */
rc = create_version_record ();
if( rc )
log_fatal( _("%s: failed to create version record: %s"),
fname, g10_errstr(rc));
/* and 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);
return 0;
}
}
xfree(db_name);
db_name = fname;
return 0;
}
const char *
tdbio_get_dbname()
{
return db_name;
}
static void
open_db()
{
TRUSTREC rec;
assert( db_fd == -1 );
if (!lockhandle )
lockhandle = create_dotlock( db_name );
if (!lockhandle )
log_fatal( _("can't create lock for `%s'\n"), db_name );
#ifdef __riscos__
if (make_dotlock( lockhandle, -1 ) )
log_fatal( _("can't lock `%s'\n"), db_name );
#endif /* __riscos__ */
db_fd = open (db_name, O_RDWR | MY_O_BINARY );
if (db_fd == -1 && (errno == EACCES
#ifdef EROFS
|| errno == EROFS)
#endif
) {
db_fd = open (db_name, O_RDONLY | MY_O_BINARY );
if (db_fd != -1)
log_info (_("NOTE: trustdb not writable\n"));
}
if ( db_fd == -1 )
log_fatal( _("can't open `%s': %s\n"), db_name, strerror(errno) );
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 );
}
/****************
* Make a hashtable: type 0 = trust hash
*/
static void
create_hashtable( 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;
assert(recnum); /* this is will never be the first record */
if( !type )
vr->r.ver.trusthashtbl = recnum;
/* Now write the records */
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( &rec );
if( rc )
log_fatal( _("%s: failed to create hashtable: %s\n"),
db_name, g10_errstr(rc));
}
/* update the version record */
rc = tdbio_write_record( vr );
if( !rc )
rc = tdbio_sync();
if( rc )
log_fatal( _("%s: error updating version record: %s\n"),
db_name, g10_errstr(rc));
}
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, g10_errstr(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;
}
return yes_no;
}
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, g10_errstr(rc) );
return vr.r.ver.trust_model;
}
/****************
* Return the nextstamp value.
*/
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, g10_errstr(rc) );
return vr.r.ver.nextcheck;
}
/* Return true when the stamp was actually changed. */
int
tdbio_write_nextcheck (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, g10_errstr(rc) );
if (vr.r.ver.nextcheck == stamp)
return 0;
vr.r.ver.nextcheck = stamp;
rc = tdbio_write_record( &vr );
if( rc )
log_fatal( _("%s: error writing version record: %s\n"),
db_name, g10_errstr(rc) );
return 1;
}
/****************
* Return the record number of the trusthash tbl or create a new one.
*/
static ulong
get_trusthashrec(void)
{
static ulong trusthashtbl; /* record number of the trust hashtable */
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, g10_errstr(rc) );
if( !vr.r.ver.trusthashtbl )
create_hashtable( &vr, 0 );
trusthashtbl = vr.r.ver.trusthashtbl;
}
return trusthashtbl;
}
/****************
* Update a hashtable.
* table gives the start of the table, key and keylen is the key,
* newrecnum is the record number to insert.
*/
static int
upd_hashtable( 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", g10_errstr(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( &rec );
if( rc ) {
log_error("upd_hashtable: write htbl failed: %s\n",
g10_errstr(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",
g10_errstr(rc) );
return rc;
}
if( rec.rectype == RECTYPE_HTBL ) {
hashrec = item;
level++;
if( level >= keylen ) {
log_error( "hashtable has invalid indirections.\n");
return G10ERR_TRUSTDB;
}
goto next_level;
}
else if( rec.rectype == RECTYPE_HLST ) { /* extend list */
/* see 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",
g10_errstr(rc) );
return rc;
}
}
else
break; /* not there */
}
/* 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] ) {
rec.r.hlst.rnum[i] = newrecnum;
rc = tdbio_write_record( &rec );
if( rc )
log_error( "upd_hashtable: write hlst failed: %s\n",
g10_errstr(rc) );
return rc; /* done */
}
}
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",
g10_errstr(rc) );
return rc;
}
}
else { /* add a new list record */
rec.r.hlst.next = item = tdbio_new_recnum();
rc = tdbio_write_record( &rec );
if( rc ) {
log_error( "upd_hashtable: write hlst failed: %s\n",
g10_errstr(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( &rec );
if( rc )
log_error( "upd_hashtable: write ext hlst failed: %s\n",
g10_errstr(rc) );
return rc; /* done */
}
} /* end loop over hlst 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();
rec.r.hlst.rnum[0] = item; /* old keyrecord */
rec.r.hlst.rnum[1] = newrecnum; /* and new one */
rc = tdbio_write_record( &rec );
if( rc ) {
log_error( "upd_hashtable: write new hlst failed: %s\n",
g10_errstr(rc) );
return rc;
}
/* update the hashtable record */
lastrec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD] = rec.recnum;
rc = tdbio_write_record( &lastrec );
if( rc )
log_error( "upd_hashtable: update htbl failed: %s\n",
g10_errstr(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);
list_trustdb(NULL);
return G10ERR_TRUSTDB;
}
}
return 0;
}
/****************
* Drop an entry from a hashtable
* table gives the start of the table, key and keylen is the key,
*/
static int
drop_from_hashtable( 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",
g10_errstr(rc) );
return rc;
}
item = rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD];
if( !item ) /* not found - forget about it */
return 0;
if( item == recnum ) { /* tables points direct to the record */
rec.r.htbl.item[msb % ITEMS_PER_HTBL_RECORD] = 0;
rc = tdbio_write_record( &rec );
if( rc )
log_error("drop_from_hashtable: write htbl failed: %s\n",
g10_errstr(rc) );
return rc;
}
rc = tdbio_read_record( item, &rec, 0 );
if( rc ) {
log_error( "drop_from_hashtable: read item failed: %s\n",
g10_errstr(rc) );
return rc;
}
if( rec.rectype == RECTYPE_HTBL ) {
hashrec = item;
level++;
if( level >= keylen ) {
log_error( "hashtable has invalid indirections.\n");
return G10ERR_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; /* drop */
rc = tdbio_write_record( &rec );
if( rc )
log_error("drop_from_hashtable: write htbl failed: %s\n",
g10_errstr(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",
g10_errstr(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 G10ERR_TRUSTDB;
}
/****************
* Lookup a record via the hashtable tablewith key/keylen and return the
* result in rec. cmp() should return if the record is the desired one.
* Returns -1 if not found, 0 if found or another errocode
*/
static int
lookup_hashtable( ulong table, const byte *key, size_t keylen,
int (*cmpfnc)(void*, const TRUSTREC *), void *cmpdata,
TRUSTREC *rec )
{
int rc;
ulong hashrec, item;
int msb;
int level=0;
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", g10_errstr(rc) );
return rc;
}
item = rec->r.htbl.item[msb % ITEMS_PER_HTBL_RECORD];
if( !item )
return -1; /* not found */
rc = tdbio_read_record( item, rec, 0 );
if( rc ) {
log_error( "hashtable read failed: %s\n", g10_errstr(rc) );
return rc;
}
if( rec->rectype == RECTYPE_HTBL ) {
hashrec = item;
level++;
if( level >= keylen ) {
log_error("hashtable has invalid indirections\n");
return G10ERR_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",
g10_errstr(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",
g10_errstr(rc) );
return rc;
}
}
else
return -1; /* not found */
}
}
if( (*cmpfnc)( cmpdata, rec ) )
return 0; /* really found */
return -1; /* no: not found */
}
/****************
* Update the trust hashtbl or create the table if it does not exist
*/
static int
update_trusthashtbl( TRUSTREC *tr )
{
return upd_hashtable( get_trusthashrec(),
tr->r.trust.fingerprint, 20, tr->recnum );
}
void
tdbio_dump_record( TRUSTREC *rec, FILE *fp )
{
int i;
ulong rnum = rec->recnum;
fprintf(fp, "rec %5lu, ", rnum );
switch( rec->rectype ) {
case 0: fprintf(fp, "blank\n");
break;
case RECTYPE_VER: fprintf(fp,
"version, td=%lu, f=%lu, m/c/d=%d/%d/%d tm=%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.nextcheck,
strtimestamp(rec->r.ver.nextcheck)
);
break;
case RECTYPE_FREE: fprintf(fp, "free, next=%lu\n", rec->r.free.next );
break;
case RECTYPE_HTBL:
fprintf(fp, "htbl,");
for(i=0; i < ITEMS_PER_HTBL_RECORD; i++ )
fprintf(fp, " %lu", rec->r.htbl.item[i] );
putc('\n', fp);
break;
case RECTYPE_HLST:
fprintf(fp, "hlst, next=%lu,", rec->r.hlst.next );
for(i=0; i < ITEMS_PER_HLST_RECORD; i++ )
fprintf(fp, " %lu", rec->r.hlst.rnum[i] );
putc('\n', fp);
break;
case RECTYPE_TRUST:
fprintf(fp, "trust ");
for(i=0; i < 20; i++ )
fprintf(fp, "%02X", rec->r.trust.fingerprint[i] );
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:
fprintf(fp, "valid ");
for(i=0; i < 20; i++ )
fprintf(fp, "%02X", rec->r.valid.namehash[i] );
fprintf (fp, ", v=%d, next=%lu\n", rec->r.valid.validity,
rec->r.valid.next);
break;
default:
fprintf(fp, "unknown type %d\n", rec->rectype );
break;
}
}
/****************
* read the record with number recnum
* returns: -1 on error, 0 on success
*/
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 -1; /* 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, "gpg", 3 ) ) {
log_error( _("%s: not a trustdb file\n"), db_name );
err = gpg_error (GPG_ERR_TRUSTDB);
}
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++;
p += 3;
rec->r.ver.created = buftoulong(p); p += 4;
rec->r.ver.nextcheck = buftoulong(p); p += 4;
p += 4;
p += 4;
rec->r.ver.firstfree =buftoulong(p); p += 4;
p += 4;
rec->r.ver.trusthashtbl =buftoulong(p); p += 4;
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 = buftoulong(p); p += 4;
break;
case RECTYPE_HTBL:
for(i=0; i < ITEMS_PER_HTBL_RECORD; i++ ) {
rec->r.htbl.item[i] = buftoulong(p); p += 4;
}
break;
case RECTYPE_HLST:
rec->r.hlst.next = buftoulong(p); p += 4;
for(i=0; i < ITEMS_PER_HLST_RECORD; i++ ) {
rec->r.hlst.rnum[i] = buftoulong(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 = buftoulong(p); p += 4;
break;
case RECTYPE_VALID:
memcpy( rec->r.valid.namehash, p, 20); p+=20;
rec->r.valid.validity = *p++;
rec->r.valid.next = buftoulong(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 at RECNUM
*/
int
tdbio_write_record( TRUSTREC *rec )
{
byte buf[TRUST_RECORD_LEN], *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, "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 += 3;
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( rec );
return rc;
}
int
tdbio_delete_record( 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( get_trusthashrec(),
rec.r.trust.fingerprint, 20, rec.recnum );
}
if( rc )
return rc;
/* now we can chnage 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, g10_errstr(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( &rec );
if( !rc )
rc = tdbio_write_record( &vr );
return rc;
}
/****************
* create a new record and return its record number
*/
ulong
tdbio_new_recnum()
{
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, g10_errstr(rc) );
if( vr.r.ver.firstfree ) {
recnum = vr.r.ver.firstfree;
rc = tdbio_read_record( recnum, &rec, RECTYPE_FREE );
if( rc ) {
log_error( _("%s: error reading free record: %s\n"),
db_name, g10_errstr(rc) );
return rc;
}
/* update dir record */
vr.r.ver.firstfree = rec.r.free.next;
rc = tdbio_write_record( &vr );
if( rc ) {
log_error( _("%s: error writing dir record: %s\n"),
db_name, g10_errstr(rc) );
return rc;
}
/*zero out the new record */
memset( &rec, 0, sizeof rec );
rec.rectype = 0; /* unused record */
rec.recnum = recnum;
rc = tdbio_write_record( &rec );
if( rc )
log_fatal(_("%s: failed to zero a record: %s\n"),
db_name, g10_errstr(rc));
}
else { /* not found, append a new record */
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;
assert(recnum); /* this is 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 = 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, strerror(errno) );
}
}
if( rc )
log_fatal(_("%s: failed to append a record: %s\n"),
db_name, g10_errstr(rc));
}
return recnum ;
}
static int
cmp_trec_fpr ( void *fpr, const TRUSTREC *rec )
{
return rec->rectype == RECTYPE_TRUST
&& !memcmp( rec->r.trust.fingerprint, fpr, 20);
}
int
tdbio_search_trust_byfpr( const byte *fingerprint, TRUSTREC *rec )
{
int rc;
/* locate the trust record using the hash table */
rc = lookup_hashtable( get_trusthashrec(), fingerprint, 20,
cmp_trec_fpr, (void*)fingerprint, rec );
return rc;
}
int
tdbio_search_trust_bypk (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 (fingerprint, rec);
}
void
tdbio_invalid(void)
{
log_error(_(
"the trustdb is corrupted; please run \"gpg --fix-trustdb\".\n") );
g10_exit(2);
}