rtp.c

	/* External RTP Bridge up, now loop and see if something happes that force us to take the
		media back to Asterisk */
	cs[0] = c0;
	cs[1] = c1;
	cs[2] = NULL;
	oldcodec0 = codec0;
	oldcodec1 = codec1;
	for (;;) {
		/* Check if something changed... */
		if ((c0->tech_pvt != pvt0)  ||
			(c1->tech_pvt != pvt1) ||
			(c0->masq || c0->masqr || c1->masq || c1->masqr)) {
				ast_log(LOG_DEBUG, "Oooh, something is weird, backing out\n");
				if (c0->tech_pvt == pvt0) {
					if (pr0->set_rtp_peer(c0, NULL, NULL, 0, 0)) 
						ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
				}
				if (c1->tech_pvt == pvt1) {
					if (pr1->set_rtp_peer(c1, NULL, NULL, 0, 0)) 
						ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);
				}
				return AST_BRIDGE_RETRY;
		}
		/* Now check if they have changed address */
		ast_rtp_get_peer(p1, &t1);
		ast_rtp_get_peer(p0, &t0);
		if (pr0->get_codec)
			codec0 = pr0->get_codec(c0);
		if (pr1->get_codec)
			codec1 = pr1->get_codec(c1);
		if (vp1)
			ast_rtp_get_peer(vp1, &vt1);
		if (vp0)
			ast_rtp_get_peer(vp0, &vt0);
		if (inaddrcmp(&t1, &ac1) || (vp1 && inaddrcmp(&vt1, &vac1)) || (codec1 != oldcodec1)) {
			if (option_debug > 1) {
				ast_log(LOG_DEBUG, "Oooh, '%s' changed end address to %s:%d (format %d)\n", 
					c1->name, ast_inet_ntoa(iabuf, sizeof(iabuf), t1.sin_addr), ntohs(t1.sin_port), codec1);
				ast_log(LOG_DEBUG, "Oooh, '%s' changed end vaddress to %s:%d (format %d)\n", 
					c1->name, ast_inet_ntoa(iabuf, sizeof(iabuf), vt1.sin_addr), ntohs(vt1.sin_port), codec1);
				ast_log(LOG_DEBUG, "Oooh, '%s' was %s:%d/(format %d)\n", 
					c1->name, ast_inet_ntoa(iabuf, sizeof(iabuf), ac1.sin_addr), ntohs(ac1.sin_port), oldcodec1);
				ast_log(LOG_DEBUG, "Oooh, '%s' was %s:%d/(format %d)\n", 
					c1->name, ast_inet_ntoa(iabuf, sizeof(iabuf), vac1.sin_addr), ntohs(vac1.sin_port), oldcodec1);
			}
			if (pr0->set_rtp_peer(c0, t1.sin_addr.s_addr ? p1 : NULL, vt1.sin_addr.s_addr ? vp1 : NULL, codec1, ast_test_flag(p1, FLAG_NAT_ACTIVE))) 
				ast_log(LOG_WARNING, "Channel '%s' failed to update to '%s'\n", c0->name, c1->name);
			memcpy(&ac1, &t1, sizeof(ac1));
			memcpy(&vac1, &vt1, sizeof(vac1));
			oldcodec1 = codec1;
		}
		if (inaddrcmp(&t0, &ac0) || (vp0 && inaddrcmp(&vt0, &vac0))) {
			if (option_debug) {
				ast_log(LOG_DEBUG, "Oooh, '%s' changed end address to %s:%d (format %d)\n", 
					c0->name, ast_inet_ntoa(iabuf, sizeof(iabuf), t0.sin_addr), ntohs(t0.sin_port), codec0);
				ast_log(LOG_DEBUG, "Oooh, '%s' was %s:%d/(format %d)\n", 
					c0->name, ast_inet_ntoa(iabuf, sizeof(iabuf), ac0.sin_addr), ntohs(ac0.sin_port), oldcodec0);
			}
			if (pr1->set_rtp_peer(c1, t0.sin_addr.s_addr ? p0 : NULL, vt0.sin_addr.s_addr ? vp0 : NULL, codec0, ast_test_flag(p0, FLAG_NAT_ACTIVE)))
				ast_log(LOG_WARNING, "Channel '%s' failed to update to '%s'\n", c1->name, c0->name);
			memcpy(&ac0, &t0, sizeof(ac0));
			memcpy(&vac0, &vt0, sizeof(vac0));
			oldcodec0 = codec0;
		}
		who = ast_waitfor_n(cs, 2, &timeoutms);
		if (!who) {
			if (!timeoutms) 
				return AST_BRIDGE_RETRY;
			if (option_debug)
				ast_log(LOG_DEBUG, "Ooh, empty read...\n");
			/* check for hangup / whentohangup */
			if (ast_check_hangup(c0) || ast_check_hangup(c1))
				break;
			continue;
		}
		f = ast_read(who);
		other = (who == c0) ? c1 : c0; /* the other channel */
		if (!f || ((f->frametype == AST_FRAME_DTMF) &&
				   (((who == c0) && (flags & AST_BRIDGE_DTMF_CHANNEL_0)) || 
			       ((who == c1) && (flags & AST_BRIDGE_DTMF_CHANNEL_1))))) {
			/* breaking out of the bridge. */
			*fo = f;
			*rc = who;
			if (option_debug)
				ast_log(LOG_DEBUG, "Oooh, got a %s\n", f ? "digit" : "hangup");
			if ((c0->tech_pvt == pvt0)) {
				if (pr0->set_rtp_peer(c0, NULL, NULL, 0, 0)) 
					ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c0->name);
			}
			if ((c1->tech_pvt == pvt1)) {
				if (pr1->set_rtp_peer(c1, NULL, NULL, 0, 0)) 
					ast_log(LOG_WARNING, "Channel '%s' failed to break RTP bridge\n", c1->name);
			}
			return AST_BRIDGE_COMPLETE;
		} else if ((f->frametype == AST_FRAME_CONTROL) && !(flags & AST_BRIDGE_IGNORE_SIGS)) {
			if ((f->subclass == AST_CONTROL_HOLD) || (f->subclass == AST_CONTROL_UNHOLD) ||
			    (f->subclass == AST_CONTROL_VIDUPDATE)) {
				ast_indicate(other, f->subclass);
				ast_frfree(f);
			} else {
				*fo = f;
				*rc = who;
				ast_log(LOG_DEBUG, "Got a FRAME_CONTROL (%d) frame on channel %s\n", f->subclass, who->name);
				return AST_BRIDGE_COMPLETE;
			}
		} else {
			if ((f->frametype == AST_FRAME_DTMF) || 
				(f->frametype == AST_FRAME_VOICE) || 
				(f->frametype == AST_FRAME_VIDEO)) {
				/* Forward voice or DTMF frames if they happen upon us */
				ast_write(other, f);
			}
			ast_frfree(f);
		}
		/* Swap priority not that it's a big deal at this point */
		cs[2] = cs[0];
		cs[0] = cs[1];
		cs[1] = cs[2];
		
	}
	return AST_BRIDGE_FAILED;
}

static int rtp_do_debug_ip(int fd, int argc, char *argv[])
{
	struct hostent *hp;
	struct ast_hostent ahp;
	char iabuf[INET_ADDRSTRLEN];
	int port = 0;
	char *p, *arg;

	if (argc != 4)
		return RESULT_SHOWUSAGE;
	arg = argv[3];
	p = strstr(arg, ":");
	if (p) {
		*p = '\0';
		p++;
		port = atoi(p);
	}
	hp = ast_gethostbyname(arg, &ahp);
	if (hp == NULL)
		return RESULT_SHOWUSAGE;
	rtpdebugaddr.sin_family = AF_INET;
	memcpy(&rtpdebugaddr.sin_addr, hp->h_addr, sizeof(rtpdebugaddr.sin_addr));
	rtpdebugaddr.sin_port = htons(port);
	if (port == 0)
		ast_cli(fd, "RTP Debugging Enabled for IP: %s\n", ast_inet_ntoa(iabuf, sizeof(iabuf), rtpdebugaddr.sin_addr));
	else
		ast_cli(fd, "RTP Debugging Enabled for IP: %s:%d\n", ast_inet_ntoa(iabuf, sizeof(iabuf), rtpdebugaddr.sin_addr), port);
	rtpdebug = 1;
	return RESULT_SUCCESS;
}

static int rtp_do_debug(int fd, int argc, char *argv[])
{
	if(argc != 2) {
		if(argc != 4)
			return RESULT_SHOWUSAGE;
		return rtp_do_debug_ip(fd, argc, argv);
	}
	rtpdebug = 1;
	memset(&rtpdebugaddr,0,sizeof(rtpdebugaddr));
	ast_cli(fd, "RTP Debugging Enabled\n");
	return RESULT_SUCCESS;
}
   
static int rtp_no_debug(int fd, int argc, char *argv[])
{
	if(argc !=3)
		return RESULT_SHOWUSAGE;
	rtpdebug = 0;
	ast_cli(fd,"RTP Debugging Disabled\n");
	return RESULT_SUCCESS;
}

static int stun_do_debug(int fd, int argc, char *argv[])
{
	if(argc != 2) {
		return RESULT_SHOWUSAGE;
	}
	stundebug = 1;
	ast_cli(fd, "STUN Debugging Enabled\n");
	return RESULT_SUCCESS;
}
   
static int stun_no_debug(int fd, int argc, char *argv[])
{
	if(argc !=3)
		return RESULT_SHOWUSAGE;
	stundebug = 0;
	ast_cli(fd,"STUN Debugging Disabled\n");
	return RESULT_SUCCESS;
}


static char debug_usage[] =
  "Usage: rtp debug [ip host[:port]]\n"
  "       Enable dumping of all RTP packets to and from host.\n";

static char no_debug_usage[] =
  "Usage: rtp no debug\n"
  "       Disable all RTP debugging\n";

static char stun_debug_usage[] =
  "Usage: stun debug\n"
  "       Enable STUN (Simple Traversal of UDP through NATs) debugging\n";

static char stun_no_debug_usage[] =
  "Usage: stun no debug\n"
  "       Disable STUN debugging\n";


static struct ast_cli_entry  cli_debug_ip =
{{ "rtp", "debug", "ip", NULL } , rtp_do_debug, "Enable RTP debugging on IP", debug_usage };

static struct ast_cli_entry  cli_debug =
{{ "rtp", "debug", NULL } , rtp_do_debug, "Enable RTP debugging", debug_usage };

static struct ast_cli_entry  cli_no_debug =
{{ "rtp", "no", "debug", NULL } , rtp_no_debug, "Disable RTP debugging", no_debug_usage };

static struct ast_cli_entry  cli_stun_debug =
{{ "stun", "debug", NULL } , stun_do_debug, "Enable STUN debugging", stun_debug_usage };

static struct ast_cli_entry  cli_stun_no_debug =
{{ "stun", "no", "debug", NULL } , stun_no_debug, "Disable STUN debugging", stun_no_debug_usage };

int ast_rtp_reload(void)
{
	struct ast_config *cfg;
	char *s;

	rtpstart = 5000;
	rtpend = 31000;
	dtmftimeout = DEFAULT_DTMF_TIMEOUT;
	cfg = ast_config_load("rtp.conf");
	if (cfg) {
		if ((s = ast_variable_retrieve(cfg, "general", "rtpstart"))) {
			rtpstart = atoi(s);
			if (rtpstart < 1024)
				rtpstart = 1024;
			if (rtpstart > 65535)
				rtpstart = 65535;
		}
		if ((s = ast_variable_retrieve(cfg, "general", "rtpend"))) {
			rtpend = atoi(s);
			if (rtpend < 1024)
				rtpend = 1024;
			if (rtpend > 65535)
				rtpend = 65535;
		}
		if ((s = ast_variable_retrieve(cfg, "general", "rtpchecksums"))) {
#ifdef SO_NO_CHECK
			if (ast_false(s))
				nochecksums = 1;
			else
				nochecksums = 0;
#else
			if (ast_false(s))
				ast_log(LOG_WARNING, "Disabling RTP checksums is not supported on this operating system!\n");
#endif
		}
		if ((s = ast_variable_retrieve(cfg, "general", "dtmftimeout"))) {
			dtmftimeout = atoi(s);
			if ((dtmftimeout < 0) || (dtmftimeout > 20000)) {
				ast_log(LOG_WARNING, "DTMF timeout of '%d' outside range, using default of '%d' instead\n",
					dtmftimeout, DEFAULT_DTMF_TIMEOUT);
				dtmftimeout = DEFAULT_DTMF_TIMEOUT;
			};
		}
		ast_config_destroy(cfg);
	}
	if (rtpstart >= rtpend) {
		ast_log(LOG_WARNING, "Unreasonable values for RTP start/end port in rtp.conf\n");
		rtpstart = 5000;
		rtpend = 31000;
	}
	if (option_verbose > 1)
		ast_verbose(VERBOSE_PREFIX_2 "RTP Allocating from port range %d -> %d\n", rtpstart, rtpend);
	return 0;
}

/*! \brief Initialize the RTP system in Asterisk */
void ast_rtp_init(void)
{
	ast_cli_register(&cli_debug);
	ast_cli_register(&cli_debug_ip);
	ast_cli_register(&cli_no_debug);
	ast_cli_register(&cli_stun_debug);
	ast_cli_register(&cli_stun_no_debug);
	ast_rtp_reload();
}