gpg: Fix cache consistency problem.

g10/keyring.c (keyring_search): Only mark the cache as completely
filled if we start the scan from the beginning of the keyring.

--
Signed-off-by: Neal H. Walfield <neal@g10code.com>
Reported-by: NIIBE Yutaka <gniibe@fsij.org>

A new feature (e8c53fc) turned up a bug whereby checking if a search
term matches multiple keys in the keyring causes the cache to be
inconsistent.

When we look for a key on the keyring, we iterate over each of the
keyblocks starting with the keyblock following the last result.  For
each keyblock, we iterate over the public key and any subkeys.  As we
iterate over each key, we first insert it into the cache and then
check if the key matches.  If so, we are done.

In pseudo code:

  for (i = last_result + 1; i < num_records; i ++)
    keyblock = get_keyblock (i)
    for (j = 1; j < len(keyblock); j ++)
      key = keyblock[j]
      update_cache (key)
      if (compare (key, search_terms))
        return ok
  cache_filled = true
  return ENOFOUND

When we look for the next match, we start with the following keyblock.
The result is that any subkeys following the key that matched are not
added to the cache (in other words, when a keyblock matches, the inner
loop did not necessarily complete and the subsequent search doesn't
resume it).

This patch includes a straightforward fix: only indicate the cache as
complete if we started the scan from the beginning of the keyring and
really didn't find anything.
This commit is contained in:
Neal H. Walfield 2015-11-11 18:26:53 +01:00
parent 67c701d1e5
commit 7546e81879
1 changed files with 4 additions and 2 deletions

View File

@ -943,6 +943,7 @@ keyring_search (KEYRING_HANDLE hd, KEYDB_SEARCH_DESC *desc,
int need_uid, need_words, need_keyid, need_fpr, any_skip;
int pk_no, uid_no;
int initial_skip;
int scanned_from_start;
int use_offtbl;
PKT_user_id *uid = NULL;
PKT_public_key *pk = NULL;
@ -1045,6 +1046,7 @@ keyring_search (KEYRING_HANDLE hd, KEYDB_SEARCH_DESC *desc,
main_offset = 0;
pk_no = uid_no = 0;
initial_skip = 1; /* skip until we see the start of a keyblock */
scanned_from_start = iobuf_tell (hd->current.iobuf) == 0;
while (!(rc=search_packet (hd->current.iobuf, &pkt, &offset, need_uid)))
{
byte afp[MAX_FINGERPRINT_LEN];
@ -1080,7 +1082,7 @@ keyring_search (KEYRING_HANDLE hd, KEYDB_SEARCH_DESC *desc,
if (need_keyid)
keyid_from_pk (pk, aki);
if (use_offtbl && !kr_offtbl_ready)
if (use_offtbl && !kr_offtbl_ready && scanned_from_start)
update_offset_hash_table (kr_offtbl, aki, main_offset);
}
else if (pkt.pkttype == PKT_USER_ID)
@ -1168,7 +1170,7 @@ keyring_search (KEYRING_HANDLE hd, KEYDB_SEARCH_DESC *desc,
hd->current.eof = 1;
/* if we scanned all keyrings, we are sure that
* all known key IDs are in our offtbl, mark that. */
if (use_offtbl && !kr_offtbl_ready)
if (use_offtbl && !kr_offtbl_ready && scanned_from_start)
{
KR_NAME kr;