TT#101201 support optional ICE-lite mode

closes #1106

Change-Id: I4a83ed2630889d8b17a0c40d971ec7946c1ed3a2

README.md

@@ -36,6 +36,7 @@ the following additional features are available:
   + Bridging between ICE-enabled and ICE-unaware user agents
   + Optionally acting only as additional ICE relay/candidate
   + Optionally forcing relay of media streams by removing other ICE candidates
+  + Optionally act as an "ICE lite" peer only
 - SRTP (RFC 3711) support:
   + Support for SDES (RFC 4568) and DTLS-SRTP (RFC 5764)
   + AES-CM and AES-F8 ciphers, both in userspace and in kernel
@@ -897,6 +898,21 @@ Optionally included keys are:
 
 	This flag operates independently of the `replace` flags.
 
+* `ICE-lite`
+
+	Contains a string which must be one of the following values:
+
+	- `forward` to enable "ICE lite" mode towards the peer that this offer is sent to.
+
+	- `backward` to enable "ICE lite" mode towards the peer that has sent this offer.
+
+	- `both` to enable "ICE lite" towards both peers.
+
+	- `off` to disable "ICE lite" towards both peers and revert to full ICE support.
+
+	The default (keyword not present at all) is to use full ICE support, or to leave the previously
+	set "ICE lite" mode unchanged. This keyword is valid in `offer` messages only.
+
 * `transport protocol`
 
 	The transport protocol specified in the SDP body is to be rewritten to the string value given here.

daemon/call.c

@@ -1282,23 +1282,46 @@ static void __ice_offer(const struct sdp_ng_flags *flags, struct call_media *thi
 		}
 	}
 
+	switch (flags->ice_lite_option) {
+		case ICE_LITE_OFF:
+			MEDIA_CLEAR(this, ICE_LITE_SELF);
+			MEDIA_CLEAR(other, ICE_LITE_SELF);
+			break;
+		case ICE_LITE_FWD:
+			MEDIA_SET(this, ICE_LITE_SELF);
+			MEDIA_CLEAR(other, ICE_LITE_SELF);
+			break;
+		case ICE_LITE_BKW:
+			MEDIA_CLEAR(this, ICE_LITE_SELF);
+			MEDIA_SET(other, ICE_LITE_SELF);
+			break;
+		case ICE_LITE_BOTH:
+			MEDIA_SET(this, ICE_LITE_SELF);
+			MEDIA_SET(other, ICE_LITE_SELF);
+			break;
+	};
+
 	/* determine roles (even if we don't actually do ICE) */
 	/* this = receiver, other = sender */
 	/* ICE_CONTROLLING is from our POV, the other ICE flags are from peer's POV */
-	if (MEDIA_ISSET(this, ICE_LITE_PEER))
+	if (MEDIA_ISSET(this, ICE_LITE_PEER) && !MEDIA_ISSET(this, ICE_LITE_SELF))
 		MEDIA_SET(this, ICE_CONTROLLING);
 	else if (!MEDIA_ISSET(this, INITIALIZED)) {
-		if (flags->opmode == OP_OFFER)
+		if (MEDIA_ISSET(this, ICE_LITE_SELF))
+			MEDIA_CLEAR(this, ICE_CONTROLLING);
+		else if (flags->opmode == OP_OFFER)
 			MEDIA_SET(this, ICE_CONTROLLING);
 		else
 			MEDIA_CLEAR(this, ICE_CONTROLLING);
 	}
 
 	/* roles are reversed for the other side */
-	if (MEDIA_ISSET(other, ICE_LITE_PEER))
+	if (MEDIA_ISSET(other, ICE_LITE_PEER) && !MEDIA_ISSET(other, ICE_LITE_SELF))
 		MEDIA_SET(other, ICE_CONTROLLING);
 	else if (!MEDIA_ISSET(other, INITIALIZED)) {
-		if (flags->opmode == OP_OFFER)
+		if (MEDIA_ISSET(other, ICE_LITE_SELF))
+			MEDIA_CLEAR(other, ICE_CONTROLLING);
+		else if (flags->opmode == OP_OFFER)
 			MEDIA_CLEAR(other, ICE_CONTROLLING);
 		else
 			MEDIA_SET(other, ICE_CONTROLLING);

daemon/call_interfaces.c

@@ -949,6 +949,37 @@ static void call_ng_process_flags(struct sdp_ng_flags *out, bencode_item_t *inpu
 		}
 	}
 
+	if (bencode_dictionary_get_str(input, "ICE-lite", &s)) {
+		switch (__csh_lookup(&s)) {
+			case CSH_LOOKUP("off"):
+			case CSH_LOOKUP("none"):
+			case CSH_LOOKUP("no"):
+				out->ice_lite_option = ICE_LITE_OFF;
+				break;
+			case CSH_LOOKUP("forward"):
+			case CSH_LOOKUP("offer"):
+			case CSH_LOOKUP("fwd"):
+			case CSH_LOOKUP("fw"):
+				out->ice_lite_option = ICE_LITE_FWD;
+				break;
+			case CSH_LOOKUP("backward"):
+			case CSH_LOOKUP("backwards"):
+			case CSH_LOOKUP("reverse"):
+			case CSH_LOOKUP("answer"):
+			case CSH_LOOKUP("back"):
+			case CSH_LOOKUP("bkw"):
+			case CSH_LOOKUP("bk"):
+				out->ice_lite_option = ICE_LITE_BKW;
+				break;
+			case CSH_LOOKUP("both"):
+				out->ice_lite_option = ICE_LITE_BOTH;
+				break;
+			default:
+				ilog(LOG_WARN, "Unknown 'ICE-lite' flag encountered: '" STR_FORMAT "'",
+						STR_FMT(&s));
+		}
+	}
+
 	if (bencode_dictionary_get_str(input, "DTLS", &s)) {
 		switch (__csh_lookup(&s)) {
 			case CSH_LOOKUP("passive"):

daemon/ice.c

@@ -237,6 +237,7 @@ static void __ice_agent_initialize(struct ice_agent *ag) {
 	ag->foundation_hash = g_hash_table_new(__found_hash, __found_equal);
 	ag->agent_flags = 0;
 	bf_copy(&ag->agent_flags, ICE_AGENT_CONTROLLING, &media->media_flags, MEDIA_FLAG_ICE_CONTROLLING);
+	bf_copy(&ag->agent_flags, ICE_AGENT_LITE_SELF, &media->media_flags, MEDIA_FLAG_ICE_LITE_SELF);
 	ag->logical_intf = media->logical_intf;
 	ag->desired_family = media->desired_family;
 	ag->nominated_pairs = g_tree_new(__pair_prio_cmp);
@@ -579,6 +580,9 @@ static void __do_ice_check(struct ice_candidate_pair *pair) {
 	struct ice_agent *ag = pair->agent;
 	u_int32_t prio, transact[3];
 
+	if (AGENT_ISSET(ag, LITE_SELF))
+		PAIR_SET(pair, SUCCEEDED);
+
 	if (PAIR_ISSET(pair, SUCCEEDED) && !PAIR_ISSET(pair, TO_USE))
 		return;
 
@@ -1096,19 +1100,23 @@ int ice_request(struct stream_fd *sfd, const endpoint_t *src,
 
 	mutex_unlock(&ag->lock);
 
-	/* determine role conflict */
+	if (!AGENT_ISSET(ag, LITE_SELF)) {
-	if (attrs->controlling && AGENT_ISSET(ag, CONTROLLING)) {
+		/* determine role conflict */
-		if (tie_breaker >= attrs->tiebreaker)
+		if (attrs->controlling && AGENT_ISSET(ag, CONTROLLING)) {
-			return -2;
+			if (tie_breaker >= attrs->tiebreaker)
-		else
+				return -2;
-			__role_change(ag, 0);
+			else
-	}
+				__role_change(ag, 0);
-	else if (attrs->controlled && !AGENT_ISSET(ag, CONTROLLING)) {
+		}
-		if (tie_breaker >= attrs->tiebreaker)
+		else if (attrs->controlled && !AGENT_ISSET(ag, CONTROLLING)) {
-			__role_change(ag, 1);
+			if (tie_breaker >= attrs->tiebreaker)
-		else
+				__role_change(ag, 1);
-			return -2;
+			else
+				return -2;
+		}
 	}
+	else
+		PAIR_SET(pair, SUCCEEDED);
 
 
 	if (PAIR_ISSET(pair, SUCCEEDED))

daemon/sdp.c

@@ -2370,6 +2370,9 @@ int sdp_replace(struct sdp_chopper *chop, GQueue *sessions, struct call_monologu
 			chopper_append_c(chop, "\r\n");
 		}
 
+		if (MEDIA_ISSET(call_media, ICE) && MEDIA_ISSET(call_media, ICE_LITE_SELF))
+			chopper_append_c(chop, "a=ice-lite\r\n");
+
 		media_index = 1;
 
 		for (k = session->media_streams.head; k; k = k->next) {

include/call.h

@@ -153,6 +153,7 @@ enum call_type {
 #define MEDIA_FLAG_PTIME_OVERRIDE		0x01000000
 #define MEDIA_FLAG_RTCP_FB			SHARED_FLAG_RTCP_FB
 #define MEDIA_FLAG_GENERATOR			0x02000000
+#define MEDIA_FLAG_ICE_LITE_SELF		0x04000000
 
 /* access macros */
 #define SP_ISSET(p, f)		bf_isset(&(p)->sp_flags, SP_FLAG_ ## f)

include/call_interfaces.h

@@ -54,6 +54,12 @@ struct sdp_ng_flags {
 		ICE_FORCE_RELAY,
 		ICE_OPTIONAL,
 	} ice_option:3;
+	enum {
+		ICE_LITE_OFF = 0,
+		ICE_LITE_FWD,
+		ICE_LITE_BKW,
+		ICE_LITE_BOTH,
+	} ice_lite_option:2;
 	int asymmetric:1,
 	    protocol_accept:1,
 	    no_redis_update:1,

include/ice.h

@@ -30,6 +30,7 @@
 #define ICE_AGENT_CONTROLLING		0x0004
 #define ICE_AGENT_NOMINATING		0x0008
 #define ICE_AGENT_USABLE		0x0010
+#define ICE_AGENT_LITE_SELF		0x0020
 
 #define ICE_PAIR_FROZEN			0x0001
 #define ICE_PAIR_IN_PROGRESS		0x0002

utils/rtpengine-ng-client

@@ -77,13 +77,14 @@ GetOptions(
 	'symmetric-codecs'		=> \$options{'symmetric codecs'},
 	'asymmetric-codecs'		=> \$options{'asymmetric codecs'},
 	'DTLS-fingerprint=s'		=> \$options{'DTLS-fingerprint'},
+	'ICE-lite=s'			=> \$options{'ICE-lite'},
 ) or die;
 
 my $cmd = shift(@ARGV) or die;
 
 my %packet = (command => $cmd);
 
-for my $x (split(/,/, 'from-tag,to-tag,call-id,transport protocol,media address,ICE,address family,DTLS,via-branch,media address,ptime,xmlrpc-callback,metadata,address,file,db-id,code,DTLS-fingerprint')) {
+for my $x (split(/,/, 'from-tag,to-tag,call-id,transport protocol,media address,ICE,address family,DTLS,via-branch,media address,ptime,xmlrpc-callback,metadata,address,file,db-id,code,DTLS-fingerprint,ICE-lite')) {
 	defined($options{$x}) and $packet{$x} = \$options{$x};
 }
 for my $x (split(/,/, 'TOS,delete-delay')) {