From 03d831ec94cd3050179327e46d44a7ed8d79bb55 Mon Sep 17 00:00:00 2001 From: Joshua Colp <jcolp@digium.com> Date: Tue, 16 Dec 2014 16:35:28 +0000 Subject: [PATCH] chan_sip: Allow T.38 switch-over when SRTP is in use. Previously when SRTP was enabled on a channel it was not possible to switch to T.38 as no crypto attributes would be present. This change makes it so it is now possible. If a T.38 re-invite comes in SRTP is terminated since in practice you can't encrypt a UDPTL stream. Now... if we were doing T.38 over RTP (which does exist) then we'd have a chance but almost nobody does that so here we are. ASTERISK-24449 #close Reported by: Andreas Steinmetz patches: udptl-ignore-srtp-v2.patch submitted by Andreas Steinmetz (license 6523) git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@429632 65c4cc65-6c06-0410-ace0-fbb531ad65f3 --- channels/chan_sip.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/channels/chan_sip.c b/channels/chan_sip.c index 5c6a843794..bf7ef406d1 100644 --- a/channels/chan_sip.c +++ b/channels/chan_sip.c @@ -10405,6 +10405,12 @@ static int process_sdp(struct sip_pvt *p, struct sip_request *req, int t38action goto process_sdp_cleanup; } + if (p->srtp && p->udptl && udptlportno != -1) { + ast_debug(1, "Terminating SRTP due to T.38 UDPTL\n"); + sip_srtp_destroy(p->srtp); + p->srtp = NULL; + } + if (secure_audio && !(p->srtp && (ast_test_flag(p->srtp, SRTP_CRYPTO_OFFER_OK)))) { ast_log(LOG_WARNING, "Can't provide secure audio requested in SDP offer\n"); res = -1; @@ -10429,7 +10435,7 @@ static int process_sdp(struct sip_pvt *p, struct sip_request *req, int t38action goto process_sdp_cleanup; } - if (!(secure_audio || secure_video) && ast_test_flag(&p->flags[1], SIP_PAGE2_USE_SRTP)) { + if (!(secure_audio || secure_video || (p->udptl && udptlportno != -1)) && ast_test_flag(&p->flags[1], SIP_PAGE2_USE_SRTP)) { ast_log(LOG_WARNING, "Matched device setup to use SRTP, but request was not!\n"); res = -1; goto process_sdp_cleanup; -- GitLab