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/

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@399939 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index a706719847994699400e39ee6bd2e1cae68b753d..eda48b88aaf0cacae962bb0e5451d2c34ebf2a98 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -20907,6 +20907,15 @@ 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) {
@@ -21762,7 +21771,11 @@ 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 75730e60e06165e24b6aa525092403ab8b5a9f1b..ec9984616a60dd031f3c40a6b0de3aaa8f856548 100644 (file)
--- a/channels/sip/include/sip.h
+++ b/channels/sip/include/sip.h
@@ -967,6 +967,7 @@ 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] */