Fix broken reinvite glare scenario.

To make a long story short, reinvite glares were broken
because Asterisk would invert the To and From headers
when ACKing a 491 response.

The reason was because the initreq of the dialog was being
changed to the incoming glared reinvite instead of being
set to the outgoing glared reinvite. This change has three
parts

* In handle_incoming, we never will reject an ACK because it
has a to-tag present, even if we think the request may be out
of dialog.
* In handle_request_invite, we do not change the initreq when
receiving a reinvite to which we will respond with a 491.
* In handle_request_invite, several superflous settings up
pendinginvite have been removed since this is dones automatically
by transmit_response_reliable

Review: https://reviewboard.asterisk.org/r/1911
........

Merged revisions 366389 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 366390 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@366401 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 3 insertions, 8 deletions

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 29b92a51c..f6fb2af7c 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -23208,9 +23208,7 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 				}
 			}
 			transmit_response_reliable(p, "491 Request Pending", req);
-			p->pendinginvite = seqno;
 			check_via(p, req);
-			copy_request(&p->initreq, req);
 			ast_debug(1, "Got INVITE on call where we already have pending INVITE, deferring that - %s\n", p->callid);
 			/* Don't destroy dialog here */
 			res = INV_REQ_FAILED;
@@ -23230,7 +23228,6 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 		if (p->owner) {
 			ast_debug(3, "INVITE w Replaces on existing call? Refusing action. [%s]\n", p->callid);
 			transmit_response_reliable(p, "400 Bad request", req);	/* The best way to not not accept the transfer */
-			p->pendinginvite = seqno;
 			check_via(p, req);
 			copy_request(&p->initreq, req);
 			/* Do not destroy existing call */
@@ -23250,7 +23247,6 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 			sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT);
 			p->invitestate = INV_COMPLETED;
 			res = INV_REQ_ERROR;
-			p->pendinginvite = seqno;
 			check_via(p, req);
 			copy_request(&p->initreq, req);
 			goto request_invite_cleanup;
@@ -23355,7 +23351,6 @@ static int handle_request_invite(struct sip_pvt *p, struct sip_request *req, int
 			refer_locked = 0;
 			p->invitestate = INV_COMPLETED;
 			res = INV_REQ_ERROR;
-			p->pendinginvite = seqno;
 			check_via(p, req);
 			copy_request(&p->initreq, req);
 			goto request_invite_cleanup;
@@ -26208,13 +26203,13 @@ static int handle_incoming(struct sip_pvt *p, struct sip_request *req, struct as
 			if (!req->ignore && req->method == SIP_INVITE) {
 				transmit_response_reliable(p, "481 Call/Transaction Does Not Exist", req);
 				/* Will cease to exist after ACK */
+				return res;
 			} else if (req->method != SIP_ACK) {
 				transmit_response(p, "481 Call/Transaction Does Not Exist", req);
 				sip_scheddestroy(p, DEFAULT_TRANS_TIMEOUT);
-			} else {
-				ast_debug(1, "Got ACK for unknown dialog... strange.\n");
+				return res;
 			}
-			return res;
+			/* Otherwise, this is an ACK. It will always have a to-tag */
 		}
 	}