diff options
| -rw-r--r-- | channels/chan_sip.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/channels/chan_sip.c b/channels/chan_sip.c index 84a52c420..25071518c 100644 --- a/channels/chan_sip.c +++ b/channels/chan_sip.c @@ -17392,6 +17392,18 @@ static int handle_request_subscribe(struct sip_pvt *p, struct sip_request *req, } if (!req->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 (req->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); + p->needdestroy = 1; + return 0; + } + /* Use this as the basis */ if (req->debug) ast_verbose("Creating new subscription\n"); |