Add support for specifying the IP address to use for media streams in sip.conf

This is the second commit for this and documents the text stream using the configured
IP address and fixes a bug in the original patch where the UDPTL stream would also
use the different IP address.

(closes issue #14729)
Reported by: _brent_
Patches:
      media_address.patch uploaded by brent (license 388)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@225089 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/CHANGES b/CHANGES
index 6ce6590db8ef4cc177e58dd12749f86558abcace..9c6d4c6e2b2c1e14bf18cb3c7421a4413841bbc9 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -48,6 +48,8 @@ SIP Changes
    configuration for the externip and externhost options when tcp or tls is used.
  * Added support for message body (stored in content variable) to SIP NOTIFY message
    accessible via AMI and CLI.
+ * Added 'media_address' configuration option which can be used to explicitly specify
+   the IP address to use in the SDP for media (audio, video, and text) streams.
 
 IAX2 Changes
 -----------

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 0f2bb81967a0c47f898331527e465c842abf008c..512a7b78b6b62ced0abae5a98b354696ca3c2d92 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -2330,6 +2330,7 @@ static struct sockaddr_in internip;
  * to support the above functions.
  */
 static struct sockaddr_in externip;            /*!< External IP address if we are behind NAT */
+static struct sockaddr_in media_address;       /*!< External RTP IP address if we are behind NAT */
 
 static char externhost[MAXHOSTNAMELEN];                /*!< External host name */
 static time_t externexpire;                    /*!< Expiration counter for re-resolving external host name in dynamic DNS */
@@ -10138,9 +10139,9 @@ static void add_noncodec_to_sdp(const struct sip_pvt *p, int format,
 /*! \brief Set all IP media addresses for this call
        \note called from add_sdp()
 */
-static void get_our_media_address(struct sip_pvt *p, int needvideo,
-       struct sockaddr_in *sin, struct sockaddr_in *vsin, struct sockaddr_in *tsin,
-       struct sockaddr_in *dest, struct sockaddr_in *vdest)
+static void get_our_media_address(struct sip_pvt *p, int needvideo, int needtext,
+                                 struct sockaddr_in *sin, struct sockaddr_in *vsin, struct sockaddr_in *tsin,
+                                 struct sockaddr_in *dest, struct sockaddr_in *vdest, struct sockaddr_in *tdest)
 {
        /* First, get our address */
        ast_rtp_instance_get_local_address(p->rtp, sin);
@@ -10155,7 +10156,7 @@ static void get_our_media_address(struct sip_pvt *p, int needvideo,
                dest->sin_port = p->redirip.sin_port;
                dest->sin_addr = p->redirip.sin_addr;
        } else {
-               dest->sin_addr = p->ourip.sin_addr;
+               dest->sin_addr = media_address.sin_addr.s_addr ? media_address.sin_addr : p->ourip.sin_addr;
                dest->sin_port = sin->sin_port;
        }
        if (needvideo) {
@@ -10164,11 +10165,20 @@ static void get_our_media_address(struct sip_pvt *p, int needvideo,
                        vdest->sin_addr = p->vredirip.sin_addr;
                        vdest->sin_port = p->vredirip.sin_port;
                } else {
-                       vdest->sin_addr = p->ourip.sin_addr;
+                       vdest->sin_addr = media_address.sin_addr.s_addr ? media_address.sin_addr : p->ourip.sin_addr;
                        vdest->sin_port = vsin->sin_port;
                }
        }
-
+       if (needtext) {
+               /* Determine text destination */
+               if (p->tredirip.sin_addr.s_addr) {
+                       tdest->sin_addr = p->tredirip.sin_addr;
+                       tdest->sin_port = p->tredirip.sin_port;
+               } else {
+                       tdest->sin_addr = media_address.sin_addr.s_addr ? media_address.sin_addr : p->ourip.sin_addr;
+                       tdest->sin_port = tsin->sin_port;
+               }
+       }
 }
 
 /*! \brief Add Session Description Protocol message
@@ -10250,9 +10260,10 @@ static enum sip_result add_sdp(struct sip_request *resp, struct sip_pvt *p, int
                        ast_debug(2, "This call needs video offers, but there's no video support enabled!\n");
        }
 
-       get_our_media_address(p, needvideo, &sin, &vsin, &tsin, &dest, &vdest);
+       get_our_media_address(p, needvideo, needtext, &sin, &vsin, &tsin, &dest, &vdest, &tdest);
 
        snprintf(owner, sizeof(owner), "o=%s %d %d IN IP4 %s\r\n", ast_strlen_zero(global_sdpowner) ? "-" : global_sdpowner, p->sessionid, p->sessionversion, ast_inet_ntoa(dest.sin_addr));
+
        snprintf(connection, sizeof(connection), "c=IN IP4 %s\r\n", ast_inet_ntoa(dest.sin_addr));
 
        if (add_audio) {
@@ -10300,14 +10311,6 @@ static enum sip_result add_sdp(struct sip_request *resp, struct sip_pvt *p, int
                if (needtext) {
                        if (sipdebug_text)
                                ast_verbose("Lets set up the text sdp\n");
-                       /* Determine text destination */
-                       if (p->tredirip.sin_addr.s_addr) {
-                               tdest.sin_addr = p->tredirip.sin_addr;
-                               tdest.sin_port = p->tredirip.sin_port;
-                       } else {
-                               tdest.sin_addr = p->ourip.sin_addr;
-                               tdest.sin_port = tsin.sin_port;
-                       }
                        ast_str_append(&m_text, 0, "m=text %d RTP/AVP", ntohs(tdest.sin_port));
                        if (debug) /* XXX should I use tdest below ? */
                                ast_verbose("Text is at %s port %d\n", ast_inet_ntoa(p->ourip.sin_addr), ntohs(tsin.sin_port)); 
@@ -10428,6 +10431,10 @@ static enum sip_result add_sdp(struct sip_request *resp, struct sip_pvt *p, int
 
                ast_str_append(&m_modem, 0, "m=image %d udptl t38", ntohs(udptldest.sin_port));
 
+               if (udptldest.sin_addr.s_addr != dest.sin_addr.s_addr) {
+                       ast_str_append(&m_modem, 0, "c=IN IP4 %s\r\n", ast_inet_ntoa(udptldest.sin_addr));
+               }
+
                ast_str_append(&a_modem, 0, "a=T38FaxVersion:%d\r\n", p->t38.our_parms.version);
                ast_str_append(&a_modem, 0, "a=T38MaxBitRate:%d\r\n", t38_get_rate(p->t38.our_parms.rate));
                if (p->t38.our_parms.fill_bit_removal) {
@@ -24952,6 +24959,7 @@ static int reload_config(enum channelreloadreason reason)
        ast_free_ha(localaddr);
        memset(&localaddr, 0, sizeof(localaddr));
        memset(&externip, 0, sizeof(externip));
+       memset(&media_address, 0, sizeof(media_address));
        memset(&default_prefs, 0 , sizeof(default_prefs));
        memset(&sip_cfg.outboundproxy, 0, sizeof(struct sip_proxy));
        sip_cfg.outboundproxy.ip.sin_port = htons(STANDARD_SIP_PORT);
@@ -25322,6 +25330,9 @@ static int reload_config(enum channelreloadreason reason)
                                localaddr = na;
                        if (ha_error)
                                ast_log(LOG_ERROR, "Bad localnet configuration value line %d : %s\n", v->lineno, v->value);
+               } else if (!strcasecmp(v->name, "media_address")) {
+                       if (ast_parse_arg(v->value, PARSE_INADDR, &media_address))
+                               ast_log(LOG_WARNING, "Invalid address for media_address keyword: %s\n", v->value);
                } else if (!strcasecmp(v->name, "externip")) {
                        if (ast_parse_arg(v->value, PARSE_INADDR, &externip))
                                ast_log(LOG_WARNING, "Invalid address for externip keyword: %s\n", v->value);

diff --git a/configs/sip.conf.sample b/configs/sip.conf.sample
index 47ada6e7a201820ff1627a19f59de3979b7af225..857886c735ed639322993a75c03c9f59c1e626bf 100644 (file)
--- a/configs/sip.conf.sample
+++ b/configs/sip.conf.sample
@@ -705,6 +705,12 @@ srvlookup=yes                   ; Enable DNS SRV lookups on outbound calls
 ;        nat = force_rport       ; Force rport to always be on.
 ;        nat = yes               ; Force rport to always be on and perform symmetric RTP.
 ;        nat = comedia           ; Use rport if the remote side says to use it and perform symmetric RTP.
+;
+; The IP address used for media (audio, video, and text) in the SDP can also be overridden by using
+; the media_address configuration option. This is only applicable to the general section and
+; can not be set per-user or per-peer.
+;
+; media_address = 172.16.42.1
 
 ;----------------------------------- MEDIA HANDLING --------------------------------
 ; By default, Asterisk tries to re-invite media streams to an optimal path. If there's