diff options
author | Jacek Konieczny <jkonieczny@eggsoft.pl> | 2016-03-25 16:59:05 +0100 |
---|---|---|
committer | Joshua Colp <jcolp@digium.com> | 2016-03-29 09:29:45 -0500 |
commit | 0cfab30b284286b74a4c58b040364b246a9680d7 (patch) | |
tree | 90ca535e3c0dd2b05d31810ae8ebf8181a88b526 /res | |
parent | 36d016b1abb6707bfde821ac2407933a447f3d13 (diff) |
res_rtp_asterisk: Use separate SRTP session for RTCP with DTLS
Asterisk uses separate UDP ports for RTP and RTCP traffic and RFC 5764
explicitly states:
There MUST be a separate DTLS-SRTP session for each distinct pair of
source and destination ports used by a media session
This means RTP keying material cannot be used for DTLS RTCP, which was
the reason why RTCP encryption would fail.
ASTERISK-25642
Change-Id: I7e8779d8b63e371088081bb113131361b2847e3a
Diffstat (limited to 'res')
-rw-r--r-- | res/res_rtp_asterisk.c | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/res/res_rtp_asterisk.c b/res/res_rtp_asterisk.c index 611920e80..b22e9cb7f 100644 --- a/res/res_rtp_asterisk.c +++ b/res/res_rtp_asterisk.c @@ -1982,19 +1982,20 @@ static int dtls_srtp_renegotiate(const void *data) return 0; } -static int dtls_srtp_setup(struct ast_rtp *rtp, struct ast_srtp *srtp, struct ast_rtp_instance *instance) +static int dtls_srtp_setup(struct ast_rtp *rtp, struct ast_srtp *srtp, struct ast_rtp_instance *instance, int rtcp) { unsigned char material[SRTP_MASTER_LEN * 2]; unsigned char *local_key, *local_salt, *remote_key, *remote_salt; struct ast_srtp_policy *local_policy, *remote_policy = NULL; struct ast_rtp_instance_stats stats = { 0, }; int res = -1; + struct dtls_details *dtls = !rtcp ? &rtp->dtls : &rtp->rtcp->dtls; /* If a fingerprint is present in the SDP make sure that the peer certificate matches it */ if (rtp->dtls_verify & AST_RTP_DTLS_VERIFY_FINGERPRINT) { X509 *certificate; - if (!(certificate = SSL_get_peer_certificate(rtp->dtls.ssl))) { + if (!(certificate = SSL_get_peer_certificate(dtls->ssl))) { ast_log(LOG_WARNING, "No certificate was provided by the peer on RTP instance '%p'\n", instance); return -1; } @@ -2028,14 +2029,14 @@ static int dtls_srtp_setup(struct ast_rtp *rtp, struct ast_srtp *srtp, struct as } /* Ensure that certificate verification was successful */ - if ((rtp->dtls_verify & AST_RTP_DTLS_VERIFY_CERTIFICATE) && SSL_get_verify_result(rtp->dtls.ssl) != X509_V_OK) { + if ((rtp->dtls_verify & AST_RTP_DTLS_VERIFY_CERTIFICATE) && SSL_get_verify_result(dtls->ssl) != X509_V_OK) { ast_log(LOG_WARNING, "Peer certificate on RTP instance '%p' failed verification test\n", instance); return -1; } /* Produce key information and set up SRTP */ - if (!SSL_export_keying_material(rtp->dtls.ssl, material, SRTP_MASTER_LEN * 2, "EXTRACTOR-dtls_srtp", 19, NULL, 0, 0)) { + if (!SSL_export_keying_material(dtls->ssl, material, SRTP_MASTER_LEN * 2, "EXTRACTOR-dtls_srtp", 19, NULL, 0, 0)) { ast_log(LOG_WARNING, "Unable to extract SRTP keying material from DTLS-SRTP negotiation on RTP instance '%p'\n", instance); return -1; @@ -2090,7 +2091,7 @@ static int dtls_srtp_setup(struct ast_rtp *rtp, struct ast_srtp *srtp, struct as res_srtp_policy->set_ssrc(remote_policy, 0, 1); - if (ast_rtp_instance_add_srtp_policy(instance, remote_policy, local_policy)) { + if (ast_rtp_instance_add_srtp_policy(instance, remote_policy, local_policy, rtcp)) { ast_log(LOG_WARNING, "Could not set policies when setting up DTLS-SRTP on '%p'\n", rtp); goto error; } @@ -2121,7 +2122,7 @@ static int __rtp_recvfrom(struct ast_rtp_instance *instance, void *buf, size_t s { int len; struct ast_rtp *rtp = ast_rtp_instance_get_data(instance); - struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance); + struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance, rtcp); char *in = buf; #ifdef HAVE_PJPROJECT struct ast_sockaddr *loop = rtcp ? &rtp->rtcp_loop : &rtp->rtp_loop; @@ -2178,10 +2179,8 @@ static int __rtp_recvfrom(struct ast_rtp_instance *instance, void *buf, size_t s if (SSL_is_init_finished(dtls->ssl)) { /* Any further connections will be existing since this is now established */ dtls->connection = AST_RTP_DTLS_CONNECTION_EXISTING; - if (!rtcp) { - /* Use the keying material to set up key/salt information */ - res = dtls_srtp_setup(rtp, srtp, instance); - } + /* Use the keying material to set up key/salt information */ + res = dtls_srtp_setup(rtp, srtp, instance, rtcp); } else { /* Since we've sent additional traffic start the timeout timer for retransmission */ dtls_srtp_start_timeout_timer(instance, rtp, rtcp); @@ -2250,7 +2249,7 @@ static int __rtp_sendto(struct ast_rtp_instance *instance, void *buf, size_t siz int len = size; void *temp = buf; struct ast_rtp *rtp = ast_rtp_instance_get_data(instance); - struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance); + struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance, rtcp); int res; *ice = 0; @@ -2950,7 +2949,8 @@ static void ast_rtp_update_source(struct ast_rtp_instance *instance) static void ast_rtp_change_source(struct ast_rtp_instance *instance) { struct ast_rtp *rtp = ast_rtp_instance_get_data(instance); - struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance); + struct ast_srtp *srtp = ast_rtp_instance_get_srtp(instance, 0); + struct ast_srtp *rtcp_srtp = ast_rtp_instance_get_srtp(instance, 1); unsigned int ssrc = ast_random(); if (!rtp->lastts) { @@ -2966,6 +2966,9 @@ static void ast_rtp_change_source(struct ast_rtp_instance *instance) if (srtp) { ast_debug(3, "Changing ssrc for SRTP from %u to %u\n", rtp->ssrc, ssrc); res_srtp->change_source(srtp, rtp->ssrc, ssrc); + if (rtcp_srtp != srtp) { + res_srtp->change_source(srtp, rtp->ssrc, ssrc); + } } rtp->ssrc = ssrc; |