diff options
Diffstat (limited to 'security/nss/lib/ssl/ssl3gthr.c')
| -rw-r--r-- | security/nss/lib/ssl/ssl3gthr.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/security/nss/lib/ssl/ssl3gthr.c b/security/nss/lib/ssl/ssl3gthr.c index 2bcc1d0aa..cf6f4cb33 100644 --- a/security/nss/lib/ssl/ssl3gthr.c +++ b/security/nss/lib/ssl/ssl3gthr.c @@ -32,6 +32,7 @@ ssl3_InitGather(sslGather *gs) gs->readOffset = 0; gs->dtlsPacketOffset = 0; gs->dtlsPacket.len = 0; + gs->rejectV2Records = PR_FALSE; status = sslBuffer_Grow(&gs->buf, 4096); return status; } @@ -147,8 +148,11 @@ ssl3_GatherData(sslSocket *ss, sslGather *gs, int flags, ssl2Gather *ssl2gs) switch (gs->state) { case GS_HEADER: /* Check for SSLv2 handshakes. Always assume SSLv3 on clients, - * support SSLv2 handshakes only when ssl2gs != NULL. */ - if (!ssl2gs || ssl3_isLikelyV3Hello(gs->hdr)) { + * support SSLv2 handshakes only when ssl2gs != NULL. + * Always assume v3 after we received the first record. */ + if (!ssl2gs || + ss->gs.rejectV2Records || + ssl3_isLikelyV3Hello(gs->hdr)) { /* Should have a non-SSLv2 record header in gs->hdr. Extract * the length of the following encrypted data, and then * read in the rest of the record into gs->inbuf. */ @@ -183,7 +187,7 @@ ssl3_GatherData(sslSocket *ss, sslGather *gs, int flags, ssl2Gather *ssl2gs) /* This is the max length for an encrypted SSLv3+ fragment. */ if (!v2HdrLength && gs->remainder > (MAX_FRAGMENT_LENGTH + 2048)) { - SSL3_SendAlert(ss, alert_fatal, unexpected_message); + SSL3_SendAlert(ss, alert_fatal, record_overflow); gs->state = GS_INIT; PORT_SetError(SSL_ERROR_RX_RECORD_TOO_LONG); return SECFailure; @@ -205,13 +209,28 @@ ssl3_GatherData(sslSocket *ss, sslGather *gs, int flags, ssl2Gather *ssl2gs) * many into the gs->hdr[] buffer. Copy them over into inbuf so * that we can properly process the hello record later. */ if (v2HdrLength) { + /* Reject v2 records that don't even carry enough data to + * resemble a valid ClientHello header. */ + if (gs->remainder < SSL_HL_CLIENT_HELLO_HBYTES) { + SSL3_SendAlert(ss, alert_fatal, illegal_parameter); + PORT_SetError(SSL_ERROR_RX_MALFORMED_CLIENT_HELLO); + return SECFailure; + } + + PORT_Assert(lbp); gs->inbuf.len = 5 - v2HdrLength; PORT_Memcpy(lbp, gs->hdr + v2HdrLength, gs->inbuf.len); gs->remainder -= gs->inbuf.len; lbp += gs->inbuf.len; } - break; /* End this case. Continue around the loop. */ + if (gs->remainder > 0) { + break; /* End this case. Continue around the loop. */ + } + + /* FALL THROUGH if (gs->remainder == 0) as we just received + * an empty record and there's really no point in calling + * ssl_DefRecv() with buf=NULL and len=0. */ case GS_DATA: /* @@ -219,6 +238,10 @@ ssl3_GatherData(sslSocket *ss, sslGather *gs, int flags, ssl2Gather *ssl2gs) */ SSL_TRC(10, ("%d: SSL[%d]: got record of %d bytes", SSL_GETPID(), ss->fd, gs->inbuf.len)); + + /* reject any v2 records from now on */ + ss->gs.rejectV2Records = PR_TRUE; + gs->state = GS_INIT; return 1; } |