diff options
| author | Tom Lane | 2015-05-22 00:41:55 +0000 |
|---|---|---|
| committer | Tom Lane | 2015-05-22 00:41:55 +0000 |
| commit | 4dddf8552801ef013c40b22915928559a6fb22a0 (patch) | |
| tree | 1eeae2f4321d65f934871d5000fdcd1608bb6483 | |
| parent | 760e7ad47959acc3908d3824a20e784f6aed9001 (diff) | |
Back-patch libpq support for TLS versions beyond v1.
Since 7.3.2, libpq has been coded in such a way that the only SSL protocol
it would allow was TLS v1. That approach is looking increasingly obsolete.
In commit 820f08cabdcbb899 we fixed it to allow TLS >= v1, but did not
back-patch the change at the time, partly out of caution and partly because
the question was confused by a contemporary server-side change to reject
the now-obsolete SSL protocol v3. 9.4 has now been out long enough that
it seems safe to assume the change is OK; hence, back-patch into 9.0-9.3.
(I also chose to back-patch some relevant comments added by commit
326e1d73c476a0b5, but did *not* change the server behavior; hence, pre-9.4
servers will continue to allow SSL v3, even though no remotely modern
client will request it.)
Per gripe from Jan Bilek.
| -rw-r--r-- | src/backend/libpq/be-secure.c | 7 | ||||
| -rw-r--r-- | src/interfaces/libpq/fe-secure.c | 11 |
2 files changed, 17 insertions, 1 deletions
diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c index f2d65cc9b36..a4a70b9539d 100644 --- a/src/backend/libpq/be-secure.c +++ b/src/backend/libpq/be-secure.c @@ -735,6 +735,13 @@ initialize_SSL(void) #endif SSL_library_init(); SSL_load_error_strings(); + + /* + * We use SSLv23_method() because it can negotiate use of the highest + * mutually supported protocol version, while alternatives like + * TLSv1_2_method() permit only one specific version. Note that we + * don't actually allow SSL v2, only v3 and TLS protocols (see below). + */ SSL_context = SSL_CTX_new(SSLv23_method()); if (!SSL_context) ereport(FATAL, diff --git a/src/interfaces/libpq/fe-secure.c b/src/interfaces/libpq/fe-secure.c index 09cffe46afb..deb9469c6b2 100644 --- a/src/interfaces/libpq/fe-secure.c +++ b/src/interfaces/libpq/fe-secure.c @@ -965,7 +965,13 @@ init_ssl_system(PGconn *conn) SSL_load_error_strings(); } - SSL_context = SSL_CTX_new(TLSv1_method()); + /* + * We use SSLv23_method() because it can negotiate use of the highest + * mutually supported protocol version, while alternatives like + * TLSv1_2_method() permit only one specific version. Note that we + * don't actually allow SSL v2 or v3, only TLS protocols (see below). + */ + SSL_context = SSL_CTX_new(SSLv23_method()); if (!SSL_context) { char *err = SSLerrmessage(); @@ -980,6 +986,9 @@ init_ssl_system(PGconn *conn) return -1; } + /* Disable old protocol versions */ + SSL_CTX_set_options(SSL_context, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3); + /* * Disable OpenSSL's moving-write-buffer sanity check, because it * causes unnecessary failures in nonblocking send cases. |