diff options
| -rw-r--r-- | src/backend/libpq/pqcomm.c | 12 | ||||
| -rw-r--r-- | src/backend/postmaster/postmaster.c | 13 | ||||
| -rw-r--r-- | src/include/libpq/libpq.h | 1 |
3 files changed, 26 insertions, 0 deletions
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c index a4f6d4deeb4..95903d60f8e 100644 --- a/src/backend/libpq/pqcomm.c +++ b/src/backend/libpq/pqcomm.c @@ -1199,6 +1199,18 @@ pq_getstring(StringInfo s) } } +/* -------------------------------- + * pq_buffer_has_data - is any buffered data available to read? + * + * This will *not* attempt to read more data. + * -------------------------------- + */ +bool +pq_buffer_has_data(void) +{ + return (PqRecvPointer < PqRecvLength); +} + /* -------------------------------- * pq_startmsgread - begin reading a message from the client. diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c index 11c61ca746f..b9098930744 100644 --- a/src/backend/postmaster/postmaster.c +++ b/src/backend/postmaster/postmaster.c @@ -2012,6 +2012,19 @@ retry1: if (SSLok == 'S' && secure_open_server(port) == -1) return STATUS_ERROR; #endif + + /* + * At this point we should have no data already buffered. If we do, + * it was received before we performed the SSL handshake, so it wasn't + * encrypted and indeed may have been injected by a man-in-the-middle. + * We report this case to the client. + */ + if (pq_buffer_has_data()) + ereport(FATAL, + (errcode(ERRCODE_PROTOCOL_VIOLATION), + errmsg("received unencrypted data after SSL request"), + errdetail("This could be either a client-software bug or evidence of an attempted man-in-the-middle attack."))); + /* regular startup packet, cancel, etc packet should follow... */ /* but not another SSL negotiation request */ return ProcessStartupPacket(port, true); diff --git a/src/include/libpq/libpq.h b/src/include/libpq/libpq.h index 7bf06c65e96..23e9905b1e0 100644 --- a/src/include/libpq/libpq.h +++ b/src/include/libpq/libpq.h @@ -70,6 +70,7 @@ extern int pq_getmessage(StringInfo s, int maxlen); extern int pq_getbyte(void); extern int pq_peekbyte(void); extern int pq_getbyte_if_available(unsigned char *c); +extern bool pq_buffer_has_data(void); extern int pq_putbytes(const char *s, size_t len); /* |