If a resubscription comes in for a dialog we no longer know about tell the remote side that the dialog does not exist so they subscribe again using a new dialog.

(closes issue #10727)
Reported by: s0l4rb03
Patches:
      10727-2.diff uploaded by file (license 11)


git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.4@104084 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 12 insertions, 0 deletions

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index de46b9b44..eca31b6fc 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -14812,6 +14812,18 @@ static int handle_request_subscribe(struct sip_pvt *p, struct sip_request *req,
 	}
 
 	if (!ast_test_flag(req, SIP_PKT_IGNORE) && !resubscribe) {	/* Set up dialog, new subscription */
+		const char *to = get_header(req, "To");
+		char totag[128];
+
+		/* Check to see if a tag was provided, if so this is actually a resubscription of a dialog we no longer know about */
+		if (!ast_strlen_zero(to) && gettag(req, "To", totag, sizeof(totag))) {
+			if (ast_test_flag(req, SIP_PKT_DEBUG))
+				ast_verbose("Received resubscription for a dialog we no longer know about. Telling remote side to subscribe again.\n");
+			transmit_response(p, "481 Subscription does not exist", req);
+			ast_set_flag(&p->flags[0], SIP_NEEDDESTROY);
+			return 0;
+		}
+
 		/* Use this as the basis */
 		if (ast_test_flag(req, SIP_PKT_DEBUG))
 			ast_verbose("Creating new subscription\n");