/****************
 * 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;
}
예제 #2
0
파일: tdbio.c 프로젝트: 0ndorio/gnupg
/*
 * 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 (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 (&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 (&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 ();
                  rc = tdbio_write_record (&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 (&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 ();
          rec.r.hlst.rnum[0] = item;	    /* Old key record */
          rec.r.hlst.rnum[1] = newrecnum; /* and new key record */
          rc = tdbio_write_record (&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 (&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 (es_stderr, NULL);
          return GPG_ERR_TRUSTDB;
	}
    }

  return 0;
}