Merged revisions 315891 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r315891 | mnicholson | 2011-04-27 13:57:56 -0500 (Wed, 27 Apr 2011) | 14 lines

  Fix our compliance with RFC 3261 section 18.2.2.

  This change optimizes the free_via() function and removes some redundant null
  checking. It also fixes compliance with RFC 3261 section 18.2.2 by always using
  the port specified in the Via header for routing responses (even when maddr is
  not set). Also the htons() function is now used when setting the port.
  Additional documentation comments have been added in various places to make the
  logic in the code clearer.

  (closes issue #18951)
  Reported by: jmls
  Patches:
        issue18951_set_proper_port_from_via.patch uploaded by wdoekes (license 717) (modified)
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@315893 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 9db4e1c772f92decc4775ff5a45a30e1a3fdee5e..f8f034133163b90f70f292896f99a8a8985229e2 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -7549,10 +7549,7 @@ static void free_via(struct sip_via *v)
                return;
        }
 
-       if (v->via) {
-               ast_free(v->via);
-       }
-
+       ast_free(v->via);
        ast_free(v);
 }
 
@@ -7675,6 +7672,21 @@ static int addr_is_multicast(struct in_addr *addr)
        return ((ntohl(addr->s_addr) & 0xf0000000) == 0xe0000000);
 }
 
+/*!
+ * \brief Process the Via header according to RFC 3261 section 18.2.2.
+ * \param p a sip_pvt structure that will be modified according to the received
+ * header
+ * \param req a sip request with a Via header to process
+ *
+ * This function will update the destination of the response according to the
+ * Via header in the request and RFC 3261 section 18.2.2. We do not have a
+ * transport layer so we ignore certain values like the 'received' param (we
+ * set the destination address to the addres the request came from in the
+ * respprep() function).
+ *
+ * \retval -1 error
+ * \retval 0 success
+ */
 static int process_via(struct sip_pvt *p, const struct sip_request *req)
 {
        struct sip_via *via = parse_via(get_header(req, "Via"));
@@ -7699,17 +7711,13 @@ static int process_via(struct sip_pvt *p, const struct sip_request *req)
                p->sa.sin_family = AF_INET;
                memcpy(&p->sa.sin_addr, hp->h_addr, sizeof(p->sa.sin_addr));
 
-               if (via->port) {
-                       p->sa.sin_port = via->port;
-               } else {
-                       p->sa.sin_port = STANDARD_SIP_PORT;
-               }
-
                if (addr_is_multicast(&p->sa.sin_addr)) {
                        setsockopt(sipsock, IPPROTO_IP, IP_MULTICAST_TTL, &via->ttl, sizeof(via->ttl));
                }
        }
 
+       p->sa.sin_port = htons(via->port ? via->port : STANDARD_SIP_PORT);
+
        free_via(via);
        return 0;
 }
@@ -9919,6 +9927,9 @@ static int respprep(struct sip_request *resp, struct sip_pvt *p, const char *msg
 
        /* default to routing the response to the address where the request
         * came from.  Since we don't have a transport layer, we do this here.
+        * The process_via() function will update the port to either the port
+        * specified in the via header or the default port later on (per RFC
+        * 3261 section 18.2.2).
         */
        p->sa = p->recv;