chan_sip: Reject calls on 200 OKs if no SDP has been received

When Asterisk receives a 200 OK in response to an invite, that peer should have
sent an SDP at some point by then. If the channel has never received an SDP,
media won't have been set and the remote address won't be known. Endpoints in
general should not be doing this. This patch makes it so that Asterisk will
simply hang up a call if it sends a 200 OK at this point. So far this odd
behavior for endpoints has only been observed in tests which involved manually
created SIP transactions in SIPp.

(closes issue ASTERISK-22424)
Reported by: Jonathan Rose
Review: https://reviewboard.asterisk.org/r/2827/
........

Merged revisions 399939 from http://svn.asterisk.org/svn/asterisk/branches/1.8

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@399962 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index d79ee3e76facdbfa63056ba0ba6bb28aea91c88c..60751348ec4de855e3881fe2977a0d76e2da581f 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -22788,6 +22788,15 @@ static void handle_response_invite(struct sip_pvt *p, int resp, const char *rest
                                        ast_set_flag(&p->flags[0], SIP_PENDINGBYE);
                                }
                        ast_rtp_instance_activate(p->rtp);
+               } else if (!reinvite) {
+                       struct ast_sockaddr remote_address = {{0,}};
+
+                       ast_rtp_instance_get_remote_address(p->rtp, &remote_address);
+                       if (ast_sockaddr_isnull(&remote_address) || (!ast_strlen_zero(p->theirprovtag) && strcmp(p->theirtag, p->theirprovtag))) {
+                               ast_log(LOG_WARNING, "Received response: \"200 OK\" from '%s' without SDP\n", p->relatedpeer->name);
+                               ast_set_flag(&p->flags[0], SIP_PENDINGBYE);
+                               ast_rtp_instance_activate(p->rtp);
+                       }
                }
 
                if (!req->ignore && p->owner) {
@@ -23710,7 +23719,11 @@ static void handle_response(struct sip_pvt *p, int resp, const char *rest, struc
 
                gettag(req, "To", tag, sizeof(tag));
                ast_string_field_set(p, theirtag, tag);
+       } else {
+               /* Store theirtag to track for changes when 200 responses to invites are received without SDP */
+               ast_string_field_set(p, theirprovtag, p->theirtag);
        }
+
        /* This needs to be configurable on a channel/peer level,
           not mandatory for all communication. Sadly enough, NAT implementations
           are not so stable so we can always rely on these headers.

diff --git a/channels/sip/include/sip.h b/channels/sip/include/sip.h
index 073f5f4d6ad45c871482877f11811b4c6125d090..d8bee122ed486bae4619671e651f571160b1a2a7 100644 (file)
--- a/channels/sip/include/sip.h
+++ b/channels/sip/include/sip.h
@@ -1038,6 +1038,7 @@ struct sip_pvt {
                AST_STRING_FIELD(rdnis);        /*!< Referring DNIS */
                AST_STRING_FIELD(redircause);   /*!< Referring cause */
                AST_STRING_FIELD(theirtag);     /*!< Their tag */
+               AST_STRING_FIELD(theirprovtag); /*!< Provisional their tag, used when evaluating responses to invites */
                AST_STRING_FIELD(tag);          /*!< Our tag for this session */
                AST_STRING_FIELD(username);     /*!< [user] name */
                AST_STRING_FIELD(peername);     /*!< [peer] name, not set if [user] */