sdp: Add support for T.38

This change adds a T.38 format which can be used in a stream
topology to specify that a UDPTL stream needs to be created.
The SDP API has been changed to understand T.38 and create
the UDPTL session, add the attributes, and parse the attributes.

This change does not change the boundary of the T.38 state
machine. It is still up to the channel driver to implement and
act on it (such as queueing control frames or reacting to them).

ASTERISK-26949

Change-Id: If28956762ccb8ead562ac6c03d162d3d6014f2c7

1 files changed, 413 insertions, 26 deletions

diff --git a/main/sdp_state.c b/main/sdp_state.c
index fc7fff449..5aee567d3 100644
--- a/main/sdp_state.c
+++ b/main/sdp_state.c
@@ -28,6 +28,7 @@
 #include "asterisk/format_cap.h"
 #include "asterisk/config.h"
 #include "asterisk/codec.h"
+#include "asterisk/udptl.h"
 
 #include "../include/asterisk/sdp.h"
 #include "asterisk/stream.h"
@@ -63,21 +64,53 @@ enum ast_sdp_role {
 
 typedef int (*state_fn)(struct ast_sdp_state *state);
 
+struct sdp_state_udptl {
+	/*! The underlying UDPTL instance */
+	struct ast_udptl *instance;
+};
+
 struct sdp_state_stream {
+	/*! Type of the stream */
+	enum ast_media_type type;
 	union {
 		/*! The underlying RTP instance */
 		struct ast_rtp_instance *instance;
+		/*! The underlying UDPTL instance */
+		struct sdp_state_udptl *udptl;
 	};
 	/*! An explicit connection address for this stream */
 	struct ast_sockaddr connection_address;
 	/*! Whether this stream is held or not */
 	unsigned int locally_held;
+	/*! UDPTL session parameters */
+	struct ast_control_t38_parameters t38_local_params;
 };
 
+static void sdp_state_udptl_destroy(void *obj)
+{
+	struct sdp_state_udptl *udptl = obj;
+
+	if (udptl->instance) {
+		ast_udptl_destroy(udptl->instance);
+	}
+}
+
 static void sdp_state_stream_free(struct sdp_state_stream *state_stream)
 {
-	if (state_stream->instance) {
-		ast_rtp_instance_destroy(state_stream->instance);
+	switch (state_stream->type) {
+	case AST_MEDIA_TYPE_AUDIO:
+	case AST_MEDIA_TYPE_VIDEO:
+		if (state_stream->instance) {
+			ast_rtp_instance_destroy(state_stream->instance);
+		}
+		break;
+	case AST_MEDIA_TYPE_IMAGE:
+		ao2_cleanup(state_stream->udptl);
+		break;
+	case AST_MEDIA_TYPE_UNKNOWN:
+	case AST_MEDIA_TYPE_TEXT:
+	case AST_MEDIA_TYPE_END:
+		break;
 	}
 	ast_free(state_stream);
 }
@@ -165,6 +198,43 @@ static struct ast_rtp_instance *create_rtp(const struct ast_sdp_options *options
 	return rtp;
 }
 
+/*! \brief Internal function which creates a UDPTL instance */
+static struct sdp_state_udptl *create_udptl(const struct ast_sdp_options *options)
+{
+	struct sdp_state_udptl *udptl;
+	struct ast_sockaddr temp_media_address;
+	static struct ast_sockaddr address_udptl;
+	struct ast_sockaddr *media_address =  &address_udptl;
+
+	if (options->bind_udptl_to_media_address && !ast_strlen_zero(options->media_address)) {
+		ast_sockaddr_parse(&temp_media_address, options->media_address, 0);
+		media_address = &temp_media_address;
+	} else {
+		if (ast_check_ipv6()) {
+			ast_sockaddr_parse(&address_udptl, "::", 0);
+		} else {
+			ast_sockaddr_parse(&address_udptl, "0.0.0.0", 0);
+		}
+	}
+
+	udptl = ao2_alloc_options(sizeof(*udptl), sdp_state_udptl_destroy, AO2_ALLOC_OPT_LOCK_NOLOCK);
+	if (!udptl) {
+		return NULL;
+	}
+
+	udptl->instance = ast_udptl_new_with_bindaddr(NULL, NULL, 0, media_address);
+	if (!udptl->instance) {
+		ao2_ref(udptl, -1);
+		return NULL;
+	}
+
+	ast_udptl_set_error_correction_scheme(udptl->instance, ast_sdp_options_get_udptl_error_correction(options));
+	ast_udptl_setnat(udptl->instance, ast_sdp_options_get_udptl_symmetric(options));
+	ast_udptl_set_far_max_datagram(udptl->instance, ast_sdp_options_get_udptl_far_max_datagram(options));
+
+	return udptl;
+}
+
 static struct sdp_state_capabilities *sdp_initialize_state_capabilities(const struct ast_stream_topology *topology,
 	const struct ast_sdp_options *options)
 {
@@ -191,22 +261,34 @@ static struct sdp_state_capabilities *sdp_initialize_state_capabilities(const st
 
 	for (i = 0; i < ast_stream_topology_get_count(topology); ++i) {
 		struct sdp_state_stream *state_stream;
-		enum ast_media_type stream_type;
 
 		state_stream = ast_calloc(1, sizeof(*state_stream));
 		if (!state_stream) {
 			return NULL;
 		}
 
-		stream_type = ast_stream_get_type(ast_stream_topology_get_stream(topology, i));
-
-		if (stream_type == AST_MEDIA_TYPE_AUDIO || stream_type == AST_MEDIA_TYPE_VIDEO) {
-			state_stream->instance = create_rtp(options, stream_type);
-		}
+		state_stream->type = ast_stream_get_type(ast_stream_topology_get_stream(topology, i));
 
-		if (!state_stream->instance) {
-			sdp_state_stream_free(state_stream);
-			return NULL;
+		switch (state_stream->type) {
+		case AST_MEDIA_TYPE_AUDIO:
+		case AST_MEDIA_TYPE_VIDEO:
+			state_stream->instance = create_rtp(options, state_stream->type);
+			if (!state_stream->instance) {
+				sdp_state_stream_free(state_stream);
+				return NULL;
+			}
+			break;
+		case AST_MEDIA_TYPE_IMAGE:
+			state_stream->udptl = create_udptl(options);
+			if (!state_stream->udptl) {
+				sdp_state_stream_free(state_stream);
+				return NULL;
+			}
+			break;
+		case AST_MEDIA_TYPE_UNKNOWN:
+		case AST_MEDIA_TYPE_TEXT:
+		case AST_MEDIA_TYPE_END:
+			break;
 		}
 
 		AST_VECTOR_APPEND(&capabilities->streams, state_stream);
@@ -314,6 +396,9 @@ struct ast_rtp_instance *ast_sdp_state_get_rtp_instance(
 	struct sdp_state_stream *stream_state;
 
 	ast_assert(sdp_state != NULL);
+	ast_assert(ast_stream_get_type(ast_stream_topology_get_stream(sdp_state->proposed_capabilities->topology,
+		stream_index)) == AST_MEDIA_TYPE_AUDIO || ast_stream_get_type(ast_stream_topology_get_stream(
+			sdp_state->proposed_capabilities->topology, stream_index)) == AST_MEDIA_TYPE_VIDEO);
 
 	stream_state = sdp_state_get_stream(sdp_state, stream_index);
 	if (!stream_state) {
@@ -323,6 +408,23 @@ struct ast_rtp_instance *ast_sdp_state_get_rtp_instance(
 	return stream_state->instance;
 }
 
+struct ast_udptl *ast_sdp_state_get_udptl_instance(
+	const struct ast_sdp_state *sdp_state, int stream_index)
+{
+	struct sdp_state_stream *stream_state;
+
+	ast_assert(sdp_state != NULL);
+	ast_assert(ast_stream_get_type(ast_stream_topology_get_stream(sdp_state->proposed_capabilities->topology,
+		stream_index)) == AST_MEDIA_TYPE_IMAGE);
+
+	stream_state = sdp_state_get_stream(sdp_state, stream_index);
+	if (!stream_state || !stream_state->udptl) {
+		return NULL;
+	}
+
+	return stream_state->udptl->instance;
+}
+
 const struct ast_sockaddr *ast_sdp_state_get_connection_address(const struct ast_sdp_state *sdp_state)
 {
 	ast_assert(sdp_state != NULL);
@@ -334,7 +436,6 @@ int ast_sdp_state_get_stream_connection_address(const struct ast_sdp_state *sdp_
 	int stream_index, struct ast_sockaddr *address)
 {
 	struct sdp_state_stream *stream_state;
-	enum ast_media_type type;
 
 	ast_assert(sdp_state != NULL);
 	ast_assert(address != NULL);
@@ -350,12 +451,18 @@ int ast_sdp_state_get_stream_connection_address(const struct ast_sdp_state *sdp_
 		return 0;
 	}
 
-	type = ast_stream_get_type(ast_stream_topology_get_stream(sdp_state->proposed_capabilities->topology,
-		stream_index));
-
-	if (type == AST_MEDIA_TYPE_AUDIO || type == AST_MEDIA_TYPE_VIDEO) {
+	switch (ast_stream_get_type(ast_stream_topology_get_stream(sdp_state->proposed_capabilities->topology,
+		stream_index))) {
+	case AST_MEDIA_TYPE_AUDIO:
+	case AST_MEDIA_TYPE_VIDEO:
 		ast_rtp_instance_get_local_address(stream_state->instance, address);
-	} else {
+		break;
+	case AST_MEDIA_TYPE_IMAGE:
+		ast_udptl_get_us(stream_state->udptl->instance, address);
+		break;
+	case AST_MEDIA_TYPE_UNKNOWN:
+	case AST_MEDIA_TYPE_TEXT:
+	case AST_MEDIA_TYPE_END:
 		return -1;
 	}
 
@@ -556,7 +663,22 @@ static struct sdp_state_capabilities *merge_capabilities(const struct sdp_state_
 			}
 
 			current_state_stream = AST_VECTOR_GET(&current->streams, current_index);
-			joint_state_stream->instance = ao2_bump(current_state_stream->instance);
+			joint_state_stream->type = current_state_stream->type;
+
+			switch (joint_state_stream->type) {
+			case AST_MEDIA_TYPE_AUDIO:
+			case AST_MEDIA_TYPE_VIDEO:
+				joint_state_stream->instance = ao2_bump(current_state_stream->instance);
+				break;
+			case AST_MEDIA_TYPE_IMAGE:
+				joint_state_stream->udptl = ao2_bump(current_state_stream->udptl);
+				joint_state_stream->t38_local_params = current_state_stream->t38_local_params;
+				break;
+			case AST_MEDIA_TYPE_UNKNOWN:
+			case AST_MEDIA_TYPE_TEXT:
+			case AST_MEDIA_TYPE_END:
+				break;
+			}
 
 			if (!ast_sockaddr_isnull(&current_state_stream->connection_address)) {
 				ast_sockaddr_copy(&joint_state_stream->connection_address, &current_state_stream->connection_address);
@@ -572,11 +694,25 @@ static struct sdp_state_capabilities *merge_capabilities(const struct sdp_state_
 			if (!joint_stream) {
 				goto fail;
 			}
-			if (new_stream_type == AST_MEDIA_TYPE_AUDIO || new_stream_type == AST_MEDIA_TYPE_VIDEO) {
+
+			switch (new_stream_type) {
+			case AST_MEDIA_TYPE_AUDIO:
+			case AST_MEDIA_TYPE_VIDEO:
 				joint_state_stream->instance = create_rtp(options, new_stream_type);
 				if (!joint_state_stream->instance) {
 					goto fail;
 				}
+				break;
+			case AST_MEDIA_TYPE_IMAGE:
+				joint_state_stream->udptl = create_udptl(options);
+				if (!joint_state_stream->udptl) {
+					goto fail;
+				}
+				break;
+			case AST_MEDIA_TYPE_UNKNOWN:
+			case AST_MEDIA_TYPE_TEXT:
+			case AST_MEDIA_TYPE_END:
+				break;
 			}
 			ast_sockaddr_setnull(&joint_state_stream->connection_address);
 			joint_state_stream->locally_held = 0;
@@ -747,6 +883,63 @@ static void update_rtp_after_merge(const struct ast_sdp_state *state, struct ast
 	}
 }
 
+/*!
+ * \brief Update UDPTL instances based on merged SDPs
+ *
+ * UDPTL instances, when first allocated, cannot make assumptions about what the other
+ * side supports and thus has to go with some default behaviors. This function gets
+ * called after we know both what we support and what the remote endpoint supports.
+ * This way, we can update the UDPTL instance to reflect what is supported by both
+ * sides.
+ *
+ * \param state The SDP state in which SDPs have been negotiated
+ * \param udptl The UDPTL instance that is being updated
+ * \param options Our locally-supported SDP options
+ * \param remote_sdp The SDP we most recently received
+ * \param remote_m_line The remote SDP stream that corresponds to the RTP instance we are modifying
+ */
+static void update_udptl_after_merge(const struct ast_sdp_state *state, struct sdp_state_udptl *udptl,
+    const struct ast_sdp_options *options,
+	const struct ast_sdp *remote_sdp,
+	const struct ast_sdp_m_line *remote_m_line)
+{
+	struct ast_sdp_a_line *a_line;
+	struct ast_sdp_c_line *c_line;
+	unsigned int fax_max_datagram;
+	struct ast_sockaddr *addrs;
+
+	a_line = ast_sdp_m_find_attribute(remote_m_line, "t38faxmaxdatagram", -1);
+	if (!a_line) {
+		a_line = ast_sdp_m_find_attribute(remote_m_line, "t38maxdatagram", -1);
+	}
+	if (a_line && !ast_sdp_options_get_udptl_far_max_datagram(options) &&
+		(sscanf(a_line->value, "%30u", &fax_max_datagram) == 1)) {
+		ast_udptl_set_far_max_datagram(udptl->instance, fax_max_datagram);
+	}
+
+	a_line = ast_sdp_m_find_attribute(remote_m_line, "t38faxudpec", -1);
+	if (a_line) {
+		if (!strcasecmp(a_line->value, "t38UDPRedundancy")) {
+			ast_udptl_set_error_correction_scheme(udptl->instance, UDPTL_ERROR_CORRECTION_REDUNDANCY);
+		} else if (!strcasecmp(a_line->value, "t38UDPFEC")) {
+			ast_udptl_set_error_correction_scheme(udptl->instance, UDPTL_ERROR_CORRECTION_FEC);
+		} else {
+			ast_udptl_set_error_correction_scheme(udptl->instance, UDPTL_ERROR_CORRECTION_NONE);
+		}
+	}
+
+	c_line = remote_sdp->c_line;
+	if (remote_m_line->c_line) {
+		c_line = remote_m_line->c_line;
+	}
+
+	if (ast_sockaddr_resolve(&addrs, c_line->address, PARSE_PORT_FORBID, AST_AF_UNSPEC) > 0) {
+		ast_sockaddr_set_port(addrs, remote_m_line->port);
+		ast_udptl_set_peer(udptl->instance, addrs);
+		ast_free(addrs);
+	}
+}
+
 static void set_negotiated_capabilities(struct ast_sdp_state *sdp_state,
 	struct sdp_state_capabilities *new_capabilities)
 {
@@ -811,14 +1004,23 @@ static int merge_sdps(struct ast_sdp_state *sdp_state,
 
 	for (i = 0; i < AST_VECTOR_SIZE(&joint_capabilities->streams); ++i) {
 		struct sdp_state_stream *state_stream;
-		enum ast_media_type stream_type;
-
-		stream_type = ast_stream_get_type(ast_stream_topology_get_stream(joint_capabilities->topology, i));
 
 		state_stream = AST_VECTOR_GET(&joint_capabilities->streams, i);
-		if ((stream_type == AST_MEDIA_TYPE_AUDIO || stream_type == AST_MEDIA_TYPE_VIDEO) && state_stream->instance) {
+
+		switch (ast_stream_get_type(ast_stream_topology_get_stream(joint_capabilities->topology, i))) {
+		case AST_MEDIA_TYPE_AUDIO:
+		case AST_MEDIA_TYPE_VIDEO:
 			update_rtp_after_merge(sdp_state, state_stream->instance, sdp_state->options,
 				remote_sdp, ast_sdp_get_m(remote_sdp, i));
+			break;
+		case AST_MEDIA_TYPE_IMAGE:
+			update_udptl_after_merge(sdp_state, state_stream->udptl, sdp_state->options,
+				remote_sdp, ast_sdp_get_m(remote_sdp, i));
+			break;
+		case AST_MEDIA_TYPE_UNKNOWN:
+		case AST_MEDIA_TYPE_TEXT:
+		case AST_MEDIA_TYPE_END:
+			break;
 		}
 	}
 
@@ -966,6 +1168,20 @@ unsigned int ast_sdp_state_get_locally_held(const struct ast_sdp_state *sdp_stat
 	return stream_state->locally_held;
 }
 
+void ast_sdp_state_set_t38_parameters(struct ast_sdp_state *sdp_state,
+	int stream_index, struct ast_control_t38_parameters *params)
+{
+	struct sdp_state_stream *stream_state;
+	ast_assert(sdp_state != NULL && params != NULL);
+
+	stream_state = sdp_state_get_stream(sdp_state, stream_index);
+	if (!stream_state) {
+		return;
+	}
+
+	stream_state->t38_local_params = *params;
+}
+
 static int sdp_add_m_from_rtp_stream(struct ast_sdp *sdp, const struct ast_sdp_state *sdp_state,
 	const struct ast_sdp_options *options, const struct sdp_state_capabilities *capabilities, int stream_index)
 {
@@ -1104,6 +1320,167 @@ static int sdp_add_m_from_rtp_stream(struct ast_sdp *sdp, const struct ast_sdp_s
 	return 0;
 }
 
+/*! \brief Get Max T.38 Transmission rate from T38 capabilities */
+static unsigned int t38_get_rate(enum ast_control_t38_rate rate)
+{
+	switch (rate) {
+	case AST_T38_RATE_2400:
+		return 2400;
+	case AST_T38_RATE_4800:
+		return 4800;
+	case AST_T38_RATE_7200:
+		return 7200;
+	case AST_T38_RATE_9600:
+		return 9600;
+	case AST_T38_RATE_12000:
+		return 12000;
+	case AST_T38_RATE_14400:
+		return 14400;
+	default:
+		return 0;
+	}
+}
+
+static int sdp_add_m_from_udptl_stream(struct ast_sdp *sdp, const struct ast_sdp_state *sdp_state,
+	const struct ast_sdp_options *options, const struct sdp_state_capabilities *capabilities, int stream_index)
+{
+	struct ast_stream *stream;
+	struct ast_sdp_m_line *m_line;
+	struct ast_sdp_payload *payload;
+	char tmp[64];
+	struct ast_sockaddr address_udptl;
+	struct sdp_state_udptl *udptl;
+	struct ast_sdp_a_line *a_line;
+	struct sdp_state_stream *stream_state;
+
+	stream = ast_stream_topology_get_stream(capabilities->topology, stream_index);
+	udptl = AST_VECTOR_GET(&capabilities->streams, stream_index)->udptl;
+
+	ast_assert(sdp && options && stream);
+
+	if (udptl) {
+		if (ast_sdp_state_get_stream_connection_address(sdp_state, 0, &address_udptl)) {
+			return -1;
+		}
+	} else {
+		ast_sockaddr_setnull(&address_udptl);
+	}
+
+	m_line = ast_sdp_m_alloc(
+		ast_codec_media_type2str(ast_stream_get_type(stream)),
+		ast_sockaddr_port(&address_udptl), 1, "udptl", NULL);
+	if (!m_line) {
+		return -1;
+	}
+
+	payload = ast_sdp_payload_alloc("t38");
+	if (!payload || ast_sdp_m_add_payload(m_line, payload)) {
+		ast_sdp_payload_free(payload);
+		ast_sdp_m_free(m_line);
+		return -1;
+	}
+
+	stream_state = sdp_state_get_stream(sdp_state, stream_index);
+
+	snprintf(tmp, sizeof(tmp), "%u", stream_state->t38_local_params.version);
+	a_line = ast_sdp_a_alloc("T38FaxVersion", tmp);
+	if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+		ast_sdp_a_free(a_line);
+		ast_sdp_m_free(m_line);
+		return -1;
+	}
+
+	snprintf(tmp, sizeof(tmp), "%u", t38_get_rate(stream_state->t38_local_params.rate));
+	a_line = ast_sdp_a_alloc("T38FaxMaxBitRate", tmp);
+	if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+		ast_sdp_a_free(a_line);
+		ast_sdp_m_free(m_line);
+		return -1;
+	}
+
+	if (stream_state->t38_local_params.fill_bit_removal) {
+		a_line = ast_sdp_a_alloc("T38FaxFillBitRemoval", "");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+	}
+
+	if (stream_state->t38_local_params.transcoding_mmr) {
+		a_line = ast_sdp_a_alloc("T38FaxTranscodingMMR", "");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+	}
+
+	if (stream_state->t38_local_params.transcoding_jbig) {
+		a_line = ast_sdp_a_alloc("T38FaxTranscodingJBIG", "");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+	}
+
+	switch (stream_state->t38_local_params.rate_management) {
+	case AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF:
+		a_line = ast_sdp_a_alloc("T38FaxRateManagement", "transferredTCF");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+		break;
+	case AST_T38_RATE_MANAGEMENT_LOCAL_TCF:
+		a_line = ast_sdp_a_alloc("T38FaxRateManagement", "localTCF");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+		break;
+	}
+
+	snprintf(tmp, sizeof(tmp), "%u", ast_udptl_get_local_max_datagram(udptl->instance));
+	a_line = ast_sdp_a_alloc("T38FaxMaxDatagram", tmp);
+	if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+		ast_sdp_a_free(a_line);
+		ast_sdp_m_free(m_line);
+		return -1;
+	}
+
+	switch (ast_udptl_get_error_correction_scheme(udptl->instance)) {
+	case UDPTL_ERROR_CORRECTION_NONE:
+		break;
+	case UDPTL_ERROR_CORRECTION_FEC:
+		a_line = ast_sdp_a_alloc("T38FaxUdpEC", "t38UDPFEC");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+		break;
+	case UDPTL_ERROR_CORRECTION_REDUNDANCY:
+		a_line = ast_sdp_a_alloc("T38FaxUdpEC", "t38UDPRedundancy");
+		if (!a_line || ast_sdp_m_add_a(m_line, a_line)) {
+			ast_sdp_a_free(a_line);
+			ast_sdp_m_free(m_line);
+			return -1;
+		}
+		break;
+	}
+
+	if (ast_sdp_add_m(sdp, m_line)) {
+		ast_sdp_m_free(m_line);
+		return -1;
+	}
+
+	return 0;
+}
+
 /*!
  * \brief Create an SDP based on current SDP state
  *
@@ -1155,12 +1532,22 @@ static struct ast_sdp *sdp_create_from_state(const struct ast_sdp_state *sdp_sta
 	stream_count = ast_stream_topology_get_count(topology);
 
 	for (stream_num = 0; stream_num < stream_count; stream_num++) {
-		enum ast_media_type type = ast_stream_get_type(ast_stream_topology_get_stream(topology, stream_num));
-
-		if (type == AST_MEDIA_TYPE_AUDIO || type == AST_MEDIA_TYPE_VIDEO) {
+		switch (ast_stream_get_type(ast_stream_topology_get_stream(topology, stream_num))) {
+		case AST_MEDIA_TYPE_AUDIO:
+		case AST_MEDIA_TYPE_VIDEO:
 			if (sdp_add_m_from_rtp_stream(sdp, sdp_state, options, capabilities, stream_num)) {
 				goto error;
 			}
+			break;
+		case AST_MEDIA_TYPE_IMAGE:
+			if (sdp_add_m_from_udptl_stream(sdp, sdp_state, options, capabilities, stream_num)) {
+				goto error;
+			}
+			break;
+		case AST_MEDIA_TYPE_UNKNOWN:
+		case AST_MEDIA_TYPE_TEXT:
+		case AST_MEDIA_TYPE_END:
+			break;
 		}
 	}