MT#56465 sdp manipulations: add media types removal

In order to be able to control, which media types
one wants to have in the call session,
add support of the "sdp-media-remove" flag.

Syntax:
"sdp-media-remove" : ["<media-type>", "<media-type>", ...]

Additionally, add according unit tests.

Change-Id: Ic52456f8124319992ea9ca8c161daefb1df46b59

daemon/call.c

@@ -2968,6 +2968,7 @@ int monologue_offer_answer(struct call_monologue *monologues[2], sdp_streams_q *
 	struct call_monologue *receiver_ml = monologues[1];
 	unsigned int num_ports_this, num_ports_other;
 	bool is_offer = (flags->opmode == OP_OFFER);
+	unsigned int medias_offset = 0; /* media indexes offset for case with media manipulations */
 
 	/* we must have a complete dialogue, even though the to-tag (monologue->tag)
 	 * may not be known yet */
@@ -2995,10 +2996,31 @@ int monologue_offer_answer(struct call_monologue *monologues[2], sdp_streams_q *
 		 * This affects later the sequencing of medias, e.g. for subscribe requests.
 		 */
 
+		/* TODO: refactor this into something more good looking code */
+		if (flags->sdp_media_remove[sp->type_id]) {
+			sp->rtp_endpoint.port = 0; /* pretend it was a zero stream */
+			sender_media = __get_media(sender_ml, sp, flags, 0);
+			sender_media->media_sdp_id = sp->media_sdp_id;
+			__media_init_from_flags(sender_media, NULL, sp, flags);
+			num_ports_other = proto_num_ports(sp->num_ports, sender_media, flags,
+					(flags->rtcp_mux_demux || flags->rtcp_mux_accept) ? true : false);
+			__disable_streams(sender_media, num_ports_other);
+			medias_offset++;
+
+			__init_interface(sender_media, &sp->direction[0], num_ports_other);
+
+			if (sender_media->logical_intf == NULL) {
+				goto error_intf;
+			}
+
+			ilog(LOG_DEBUG, "Media type '"STR_FORMAT"' is to be removed by SDP manipulations.", STR_FMT(&sp->type));
+			continue;
+		}
+
 		/* OP_OFFER, receiver's side, get by index */
 		receiver_media = NULL;
 		if (is_offer)
-			receiver_media = __get_media(receiver_ml, sp, flags, 0);
+			receiver_media = __get_media(receiver_ml, sp, flags, (medias_offset ? (sp->index - medias_offset) : 0));
 
 		/* OP_OFFER/OP_ANSWER, sender's side, get by index */
 		sender_media = __get_media(sender_ml, sp, flags, 0);

daemon/call_interfaces.c

@@ -642,6 +642,9 @@ err:
 	ilog(LOG_WARN, "SDP manipulations: Ignoring invalid contents of string-pair list");
 }
 
+/**
+ * SDP attribute manipulation praser helpers.
+ */
 static void ng_sdp_attr_media_iter(const ng_parser_t *parser, str *command_type, parser_arg command_value,
 		helper_arg arg)
 {
@@ -684,6 +687,27 @@ INLINE void ng_sdp_attr_manipulations(const ng_parser_t *parser, sdp_ng_flags *f
 		ilog(LOG_WARN, "SDP manipulations: Wrong type for this type of command.");
 }
 
+/**
+ * SDP media section manipulation parser helpers.
+ */
+static void ng_sdp_media_remove_iter(str *media_type, unsigned int i, helper_arg arg)
+{
+	enum media_type id = codec_get_type(media_type);
+	if (id == MT_UNKNOWN || id == MT_OTHER)
+	{
+		ilog(LOG_WARN, "SDP manipulations: unsupported SDP section '" STR_FORMAT "' targeted.",
+				STR_FMT(media_type));
+		/* only known media types are supported */
+		return;
+	}
+	arg.flags->sdp_media_remove[id] = true;
+}
+INLINE void ng_sdp_media_remove(const ng_parser_t *parser, sdp_ng_flags *flags, parser_arg value) {
+	if (!parser->is_list(value))
+		return;
+	parser->list_iter(parser, value, ng_sdp_media_remove_iter, NULL, flags);
+}
+
 INLINE void ng_el_option(str *s, unsigned int idx, helper_arg arg) {
 	sdp_ng_flags *out = arg.flags;
 	switch (__csh_lookup(s)) {
@@ -1290,6 +1314,8 @@ void call_ng_flags_init(sdp_ng_flags *out, enum call_opmode opmode) {
 	out->volume = 9999;
 	out->digit = -1;
 	out->frequencies = g_array_new(false, false, sizeof(int));
+	for (int i = 0; i < __MT_MAX; ++i)
+		out->sdp_media_remove[i] = false;
 }
 
 static void call_ng_direction_flag_iter(str *s, unsigned int i, helper_arg arg) {
@@ -1883,6 +1909,12 @@ void call_ng_main_flags(const ng_parser_t *parser, str *key, parser_arg value, h
 		case CSH_LOOKUP("SDP-attr"):
 			ng_sdp_attr_manipulations(parser, out, value);
 			break;
+		case CSH_LOOKUP("sdp-media-remove"):
+		case CSH_LOOKUP("SDP-media-remove"):
+		case CSH_LOOKUP("sdp_media_remove"):
+		case CSH_LOOKUP("SDP_media_remove"):
+			ng_sdp_media_remove(parser, out, value);
+			break;
 		case CSH_LOOKUP("set-label"):
 			out->set_label = s;
 			break;

include/call_interfaces.h

@@ -72,6 +72,8 @@ struct sdp_ng_flags {
 
 	/* commands to manipulate attr lines in SDP */
 	struct sdp_manipulations * sdp_manipulations[__MT_MAX];
+	/* types of medias to be removed by media lvl manipulations */
+	bool sdp_media_remove[__MT_MAX];
 
 	enum {
 		ICE_DEFAULT = 0,
@@ -321,6 +323,7 @@ INLINE struct sdp_manipulations *sdp_manipulations_get_by_name(struct sdp_manipu
 		return NULL;
 	return sdp_manipulations_get_create_by_id(array, id);
 }
+
 // set all WebRTC-specific attributes
 INLINE void ng_flags_webrtc(sdp_ng_flags *f) {
 	f->transport_protocol = &transport_protocols[PROTO_UDP_TLS_RTP_SAVPF];

t/auto-daemon-tests.pl

@@ -20541,6 +20541,124 @@ a=crypto:4 AES_256_CM_HMAC_SHA1_32 inline:CRYPTO256
 SDP
 
 
+# Arbitrary SDP media level manipulations
+
+new_call;
+
+offer('SDP media manipulations - remove video', { ICE => 'remove', DTLS => 'off', SDES => [ 'nonew' ], 'sdp-media-remove' => ['video']}, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio 2000 RTP/SAVP 0
+c=IN IP4 198.51.100.1
+a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:cJOJ7kxQjhFBp2fP6AYjs3vKw7CeBdWZCj0isbJv
+a=crypto:2 AES_CM_128_HMAC_SHA1_32 inline:VAzLKvoE3jG9cdH/AZsl/ZqWNXrUzyM4Gw6chrFr
+a=crypto:3 AES_256_CM_HMAC_SHA1_80 inline:8AbZePWwsKhLGX3GlXA+yHYPQ3cgraer/9DkFJYCOPZZy3o9wC0NIbIFYZfyHw==
+a=crypto:4 AES_256_CM_HMAC_SHA1_32 inline:2GLk3p/csdno4KlGO1TxCVaEt+bifmDlQ5NjnCb5cJYPURiGRSTBEtEq37db8g==
+a=sendrecv
+m=video 3000 RTP/AVP 97
+c=IN IP4 198.51.100.1
+a=rtpmap:97 H264/90000
+a=fmtp:97 0-15
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio PORT RTP/SAVP 0
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:CRYPTO128
+a=crypto:2 AES_CM_128_HMAC_SHA1_32 inline:CRYPTO128
+a=crypto:3 AES_256_CM_HMAC_SHA1_80 inline:CRYPTO256
+a=crypto:4 AES_256_CM_HMAC_SHA1_32 inline:CRYPTO256
+SDP
+
+answer('SDP media manipulations - remove video', { ICE => 'remove' }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.3
+s=tester
+t=0 0
+m=audio 2002 RTP/SAVP 0
+c=IN IP4 198.51.100.3
+a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:n2YhgclGcmcPp71u6pjbgu41KYAvsaTE3gRmJYJC
+a=sendrecv
+--------------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.3
+s=tester
+t=0 0
+m=audio PORT RTP/SAVP 0
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:CRYPTO128
+m=video 0 RTP/AVP 0
+c=IN IP4 0.0.0.0
+SDP
+
+new_call;
+
+offer('SDP media manipulations - remove audio', { ICE => 'remove', DTLS => 'off', SDES => [ 'nonew' ], 'sdp-media-remove' => ['audio']}, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio 2000 RTP/SAVP 0
+c=IN IP4 198.51.100.1
+a=crypto:1 AES_CM_128_HMAC_SHA1_80 inline:cJOJ7kxQjhFBp2fP6AYjs3vKw7CeBdWZCj0isbJv
+a=crypto:2 AES_CM_128_HMAC_SHA1_32 inline:VAzLKvoE3jG9cdH/AZsl/ZqWNXrUzyM4Gw6chrFr
+a=crypto:3 AES_256_CM_HMAC_SHA1_80 inline:8AbZePWwsKhLGX3GlXA+yHYPQ3cgraer/9DkFJYCOPZZy3o9wC0NIbIFYZfyHw==
+a=crypto:4 AES_256_CM_HMAC_SHA1_32 inline:2GLk3p/csdno4KlGO1TxCVaEt+bifmDlQ5NjnCb5cJYPURiGRSTBEtEq37db8g==
+a=sendrecv
+m=video 3000 RTP/AVP 97
+c=IN IP4 198.51.100.1
+a=rtpmap:97 H264/90000
+a=fmtp:97 0-15
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=video PORT RTP/AVP 97
+c=IN IP4 203.0.113.1
+a=rtpmap:97 H264/90000
+a=fmtp:97 0-15
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+answer('SDP media manipulations - remove audio', { ICE => 'remove' }, <<SDP);
+v=0
+o=- 1115997027 1 IN IP4 198.51.100.3
+s=tester
+t=0 0
+m=video 4000 RTP/AVP 97
+a=rtpmap:97 H264/90000
+a=fmtp:97 0-15
+c=IN IP4 198.51.100.3
+a=sendrecv
+--------------------------------------
+v=0
+o=- 1115997027 1 IN IP4 198.51.100.3
+s=tester
+t=0 0
+m=audio 0 RTP/SAVP 0
+c=IN IP4 0.0.0.0
+m=video PORT RTP/AVP 97
+c=IN IP4 203.0.113.1
+a=rtpmap:97 H264/90000
+a=fmtp:97 0-15
+a=sendrecv
+a=rtcp:PORT
+SDP
+
 # Arbitrary SDP manipulations
 
 new_call;