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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2006-05-21 20:22:16 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2006-05-21 20:22:16 +0000 |
| commit | 5cf07901c5118a55c9d8e1c704283cfc744bb68b (patch) | |
| tree | 3ae8c525f6c60519e5a90d2feeafe665257c9c97 | |
| parent | 515112f9d4874aaedd0c093f41c0ba3e0bf7f660 (diff) | |
| download | postgresql-5cf07901c5118a55c9d8e1c704283cfc744bb68b.tar.gz postgresql-5cf07901c5118a55c9d8e1c704283cfc744bb68b.zip | |
Fix errors in fortuna PRNG reseeding logic that could cause a predictable
session key to be selected by pgp_sym_encrypt() in some cases. This only
affects non-OpenSSL-using builds. Marko Kreen
| -rw-r--r-- | contrib/pgcrypto/fortuna.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/contrib/pgcrypto/fortuna.c b/contrib/pgcrypto/fortuna.c index 1b13337301c..cf69cee28bc 100644 --- a/contrib/pgcrypto/fortuna.c +++ b/contrib/pgcrypto/fortuna.c @@ -26,7 +26,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $PostgreSQL: pgsql/contrib/pgcrypto/fortuna.c,v 1.5 2005/10/15 02:49:06 momjian Exp $ + * $PostgreSQL: pgsql/contrib/pgcrypto/fortuna.c,v 1.6 2006/05/21 20:22:16 tgl Exp $ */ #include "postgres.h" @@ -219,7 +219,7 @@ encrypt_counter(FState * st, uint8 *dst) * microseconds. */ static int -too_often(FState * st) +enough_time_passed(FState * st) { int ok; struct timeval tv; @@ -227,13 +227,22 @@ too_often(FState * st) gettimeofday(&tv, NULL); + /* check how much time has passed */ ok = 0; - if (tv.tv_sec != last->tv_sec) + if (tv.tv_sec > last->tv_sec + 1) ok = 1; + else if (tv.tv_sec == last->tv_sec + 1) + { + if (1000000 + tv.tv_usec - last->tv_usec >= RESEED_INTERVAL) + ok = 1; + } else if (tv.tv_usec - last->tv_usec >= RESEED_INTERVAL) ok = 1; - memcpy(last, &tv, sizeof(tv)); + /* reseed will happen, update last_reseed_time */ + if (ok) + memcpy(last, &tv, sizeof(tv)); + memset(&tv, 0, sizeof(tv)); return ok; @@ -372,7 +381,7 @@ extract_data(FState * st, unsigned count, uint8 *dst) unsigned block_nr = 0; /* Can we reseed? */ - if (st->pool0_bytes >= POOL0_FILL && !too_often(st)) + if (st->pool0_bytes >= POOL0_FILL && enough_time_passed(st)) reseed(st); /* Is counter initialized? */ |