From 9d47b0498a836777fd7015fc2720cedb141c19a4 Mon Sep 17 00:00:00 2001 From: dvossel Date: Tue, 22 Jun 2010 20:37:05 +0000 Subject: ignore CANCEL request after having already received final response to INVITE RFC 3261 section 9 states that a CANCEL has no effect on a request to a UAS that has already given a final response. This patch checks to make sure there is a pending invite before allowing a CANCEL request to be processed, otherwise it responds to the CANCEL with a "481 Call/Transaction Does Not Exist". Review: https://reviewboard.asterisk.org/r/697/ git-svn-id: http://svn.digium.com/svn/asterisk/trunk@271977 f38db490-d61c-443f-a65b-d21fe96a405b --- channels/chan_sip.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'channels') diff --git a/channels/chan_sip.c b/channels/chan_sip.c index 60ab323f0..fa03d9c43 100644 --- a/channels/chan_sip.c +++ b/channels/chan_sip.c @@ -23079,7 +23079,14 @@ static int handle_incoming(struct sip_pvt *p, struct sip_request *req, struct so req->ignore = 1; ast_debug(3, "Ignoring SIP message because of retransmit (%s Seqno %d, ours %d)\n", sip_methods[p->method].text, p->icseq, seqno); } - + + /* RFC 3261 section 9. "CANCEL has no effect on a request to which a UAS has + * already given a final response." */ + if (!p->pendinginvite && (req->method == SIP_CANCEL)) { + transmit_response(p, "481 Call/Transaction Does Not Exist", req); + return res; + } + if (seqno >= p->icseq) /* Next should follow monotonically (but not necessarily incrementally -- thanks again to the genius authors of SIP -- -- cgit v1.2.3