GST_END_TEST GST_START_TEST (media_from_caps_rtcp_fb_pt_101) { GstSDPResult ret = GST_SDP_OK; GstSDPMessage *message; glong length = -1; GstSDPMedia *media_caps; const GstSDPMedia *media_sdp; GstCaps *caps; const gchar *attr_val_caps1, *attr_val_sdp1; caps = gst_caps_from_string (caps_video_rtcp_fb_pt_101); gst_sdp_media_new (&media_caps); fail_unless (media_caps != NULL); ret = gst_sdp_media_set_media_from_caps (caps, media_caps); fail_unless (ret == GST_SDP_OK); gst_caps_unref (caps); gst_sdp_message_new (&message); gst_sdp_message_parse_buffer ((guint8 *) sdp_rtcp_fb, length, message); media_sdp = gst_sdp_message_get_media (message, 0); fail_unless (media_sdp != NULL); attr_val_caps1 = gst_sdp_media_get_attribute_val (media_caps, "rtcp-fb"); attr_val_sdp1 = gst_sdp_media_get_attribute_val_n (media_sdp, "rtcp-fb", 3); fail_if (g_strcmp0 (attr_val_caps1, attr_val_sdp1) != 0); gst_sdp_media_free (media_caps); gst_sdp_message_free (message); }
static GstSDPMedia * kms_sdp_rtp_avpf_media_handler_create_offer (KmsSdpMediaHandler * handler, const gchar * media, GError ** error) { GstSDPMedia *m; if (gst_sdp_media_new (&m) != GST_SDP_OK) { g_set_error (error, KMS_SDP_AGENT_ERROR, SDP_AGENT_UNEXPECTED_ERROR, "Can not create '%s' media", media); goto error; } /* Create m-line */ if (!KMS_SDP_MEDIA_HANDLER_CLASS (parent_class)->init_offer (handler, media, m, error)) { goto error; } /* Add attributes to m-line */ if (!KMS_SDP_MEDIA_HANDLER_GET_CLASS (handler)->add_offer_attributes (handler, m, error)) { goto error; } return m; error: if (m != NULL) { gst_sdp_media_free (m); } return NULL; }
static GstSDPMedia * reject_media_answer (const GstSDPMedia * offered) { GstSDPMedia *media; const gchar *mid; guint i, len; gst_sdp_media_new (&media); /* [rfc3264] To reject an offered stream, the port number in the */ /* corresponding stream in the answer MUST be set to zero. Any */ /* media formats listed are ignored. */ gst_sdp_media_set_media (media, gst_sdp_media_get_media (offered)); gst_sdp_media_set_port_info (media, 0, 1); gst_sdp_media_set_proto (media, gst_sdp_media_get_proto (offered)); len = gst_sdp_media_formats_len (offered); for (i = 0; i < len; i++) { const gchar *format; format = gst_sdp_media_get_format (offered, i); gst_sdp_media_insert_format (media, i, format); } /* [rfc5888] mid attribute must be present in answer as well */ mid = gst_sdp_media_get_attribute_val (offered, "mid"); if (mid == NULL) { return media; } gst_sdp_media_add_attribute (media, "mid", mid); return media; }
GstSDPMedia * kms_sdp_reject_media_handler_create_answer (KmsSdpMediaHandler * handler, const GstSDPMessage * msg, const GstSDPMedia * offer, GError ** error) { GstSDPMedia *m = NULL; if (gst_sdp_media_new (&m) != GST_SDP_OK) { g_set_error (error, KMS_SDP_AGENT_ERROR, SDP_AGENT_UNEXPECTED_ERROR, "Can not create '%s' media answer", gst_sdp_media_get_media (offer)); goto error; } /* Create m-line */ if (!KMS_SDP_MEDIA_HANDLER_GET_CLASS (handler)->init_answer (handler, offer, m, error)) { goto error; } /* Add attributes to m-line */ if (!KMS_SDP_MEDIA_HANDLER_GET_CLASS (handler)->add_answer_attributes (handler, offer, m, error)) { goto error; } return m; error: if (m != NULL) { gst_sdp_media_free (m); } return NULL; }
GST_END_TEST GST_START_TEST (media_from_caps) { GstSDPResult ret = GST_SDP_OK; GstSDPMessage *message; glong length = -1; GstSDPMedia *media_video, *media_audio; const GstSDPMedia *result_video, *result_audio; GstCaps *caps_video, *caps_audio; const gchar *media1_text, *media2_text, *media3_text, *media4_text; caps_video = gst_caps_from_string (caps_video_string1); caps_audio = gst_caps_from_string (caps_audio_string); gst_sdp_media_new (&media_video); fail_unless (media_video != NULL); gst_sdp_media_new (&media_audio); fail_unless (media_audio != NULL); ret = gst_sdp_media_set_media_from_caps (caps_video, media_video); fail_unless (ret == GST_SDP_OK); gst_caps_unref (caps_video); ret = gst_sdp_media_set_media_from_caps (caps_audio, media_audio); fail_unless (ret == GST_SDP_OK); gst_caps_unref (caps_audio); gst_sdp_message_new (&message); gst_sdp_message_parse_buffer ((guint8 *) sdp, length, message); result_video = gst_sdp_message_get_media (message, 0); fail_unless (result_video != NULL); result_audio = gst_sdp_message_get_media (message, 2); fail_unless (result_audio != NULL); media1_text = gst_sdp_media_get_attribute_val (media_video, "rtpmap"); media2_text = gst_sdp_media_get_attribute_val (result_video, "rtpmap"); media3_text = gst_sdp_media_get_format (media_audio, 0); media4_text = gst_sdp_media_get_format (result_audio, 0); fail_if (g_strcmp0 (media1_text, media2_text) != 0); fail_if (g_strcmp0 (media3_text, media4_text) != 0); gst_sdp_media_free (media_video); gst_sdp_media_free (media_audio); gst_sdp_message_free (message); }
static void make_media (GstSDPMessage * sdp, GstSDPInfo * info, GstRTSPMedia * media, GstRTSPStream * stream, GstStructure * s, GstRTSPProfile profile) { GstSDPMedia *smedia; const gchar *caps_str, *caps_enc, *caps_params; gchar *tmp; gint caps_pt, caps_rate; guint n_fields, j; gboolean first; GString *fmtp; GstRTSPLowerTrans ltrans; GSocketFamily family; const gchar *addrtype, *proto; gchar *address; guint ttl; GstClockTime rtx_time; gst_sdp_media_new (&smedia); /* get media type and payload for the m= line */ caps_str = gst_structure_get_string (s, "media"); gst_sdp_media_set_media (smedia, caps_str); gst_structure_get_int (s, "payload", &caps_pt); tmp = g_strdup_printf ("%d", caps_pt); gst_sdp_media_add_format (smedia, tmp); g_free (tmp); gst_sdp_media_set_port_info (smedia, 0, 1); switch (profile) { case GST_RTSP_PROFILE_AVP: proto = "RTP/AVP"; break; case GST_RTSP_PROFILE_AVPF: proto = "RTP/AVPF"; break; case GST_RTSP_PROFILE_SAVP: proto = "RTP/SAVP"; break; case GST_RTSP_PROFILE_SAVPF: proto = "RTP/SAVPF"; break; default: proto = "udp"; break; } gst_sdp_media_set_proto (smedia, proto); if (info->is_ipv6) { addrtype = "IP6"; family = G_SOCKET_FAMILY_IPV6; } else { addrtype = "IP4"; family = G_SOCKET_FAMILY_IPV4; } ltrans = gst_rtsp_stream_get_protocols (stream); if (ltrans == GST_RTSP_LOWER_TRANS_UDP_MCAST) { GstRTSPAddress *addr; addr = gst_rtsp_stream_get_multicast_address (stream, family); if (addr == NULL) goto no_multicast; address = g_strdup (addr->address); ttl = addr->ttl; gst_rtsp_address_free (addr); } else { ttl = 16; if (info->is_ipv6) address = g_strdup ("::"); else address = g_strdup ("0.0.0.0"); } /* for the c= line */ gst_sdp_media_add_connection (smedia, "IN", addrtype, address, ttl, 1); g_free (address); /* get clock-rate, media type and params for the rtpmap attribute */ gst_structure_get_int (s, "clock-rate", &caps_rate); caps_enc = gst_structure_get_string (s, "encoding-name"); caps_params = gst_structure_get_string (s, "encoding-params"); if (caps_enc) { if (caps_params) tmp = g_strdup_printf ("%d %s/%d/%s", caps_pt, caps_enc, caps_rate, caps_params); else tmp = g_strdup_printf ("%d %s/%d", caps_pt, caps_enc, caps_rate); gst_sdp_media_add_attribute (smedia, "rtpmap", tmp); g_free (tmp); } /* the config uri */ tmp = gst_rtsp_stream_get_control (stream); gst_sdp_media_add_attribute (smedia, "control", tmp); g_free (tmp); /* check for srtp */ do { GstBuffer *srtpkey; const GValue *val; const gchar *srtpcipher, *srtpauth, *srtcpcipher, *srtcpauth; GstMIKEYMessage *msg; GstMIKEYPayload *payload, *pkd; GBytes *bytes; GstMapInfo info; const guint8 *data; gsize size; gchar *base64; guint8 byte; guint32 ssrc; val = gst_structure_get_value (s, "srtp-key"); if (val == NULL) break; srtpkey = gst_value_get_buffer (val); if (srtpkey == NULL) break; srtpcipher = gst_structure_get_string (s, "srtp-cipher"); srtpauth = gst_structure_get_string (s, "srtp-auth"); srtcpcipher = gst_structure_get_string (s, "srtcp-cipher"); srtcpauth = gst_structure_get_string (s, "srtcp-auth"); if (srtpcipher == NULL || srtpauth == NULL || srtcpcipher == NULL || srtcpauth == NULL) break; msg = gst_mikey_message_new (); /* unencrypted MIKEY message, we send this over TLS so this is allowed */ gst_mikey_message_set_info (msg, GST_MIKEY_VERSION, GST_MIKEY_TYPE_PSK_INIT, FALSE, GST_MIKEY_PRF_MIKEY_1, 0, GST_MIKEY_MAP_TYPE_SRTP); /* add policy '0' for our SSRC */ gst_rtsp_stream_get_ssrc (stream, &ssrc); gst_mikey_message_add_cs_srtp (msg, 0, ssrc, 0); /* timestamp is now */ gst_mikey_message_add_t_now_ntp_utc (msg); /* add some random data */ gst_mikey_message_add_rand_len (msg, 16); /* the policy '0' is SRTP with the above discovered algorithms */ payload = gst_mikey_payload_new (GST_MIKEY_PT_SP); gst_mikey_payload_sp_set (payload, 0, GST_MIKEY_SEC_PROTO_SRTP); /* only AES-CM is supported */ byte = 1; gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_ENC_ALG, 1, &byte); /* Encryption key length */ byte = enc_key_length_from_cipher_name (srtpcipher); gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_ENC_KEY_LEN, 1, &byte); /* only HMAC-SHA1 */ gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_AUTH_ALG, 1, &byte); /* Authentication key length */ byte = auth_key_length_from_auth_name (srtpauth); gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_AUTH_KEY_LEN, 1, &byte); /* we enable encryption on RTP and RTCP */ gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_SRTP_ENC, 1, &byte); gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_SRTCP_ENC, 1, &byte); /* we enable authentication on RTP and RTCP */ gst_mikey_payload_sp_add_param (payload, GST_MIKEY_SP_SRTP_SRTP_AUTH, 1, &byte); gst_mikey_message_add_payload (msg, payload); /* make unencrypted KEMAC */ payload = gst_mikey_payload_new (GST_MIKEY_PT_KEMAC); gst_mikey_payload_kemac_set (payload, GST_MIKEY_ENC_NULL, GST_MIKEY_MAC_NULL); /* add the key in key data */ pkd = gst_mikey_payload_new (GST_MIKEY_PT_KEY_DATA); gst_buffer_map (srtpkey, &info, GST_MAP_READ); gst_mikey_payload_key_data_set_key (pkd, GST_MIKEY_KD_TEK, info.size, info.data); gst_buffer_unmap (srtpkey, &info); /* add key data to KEMAC */ gst_mikey_payload_kemac_add_sub (payload, pkd); gst_mikey_message_add_payload (msg, payload); /* now serialize this to bytes */ bytes = gst_mikey_message_to_bytes (msg, NULL, NULL); gst_mikey_message_unref (msg); /* and make it into base64 */ data = g_bytes_get_data (bytes, &size); base64 = g_base64_encode (data, size); g_bytes_unref (bytes); tmp = g_strdup_printf ("mikey %s", base64); g_free (base64); gst_sdp_media_add_attribute (smedia, "key-mgmt", tmp); g_free (tmp); } while (FALSE); /* collect all other properties and add them to fmtp or attributes */ fmtp = g_string_new (""); g_string_append_printf (fmtp, "%d ", caps_pt); first = TRUE; n_fields = gst_structure_n_fields (s); for (j = 0; j < n_fields; j++) { const gchar *fname, *fval; fname = gst_structure_nth_field_name (s, j); /* filter out standard properties */ if (!strcmp (fname, "media")) continue; if (!strcmp (fname, "payload")) continue; if (!strcmp (fname, "clock-rate")) continue; if (!strcmp (fname, "encoding-name")) continue; if (!strcmp (fname, "encoding-params")) continue; if (!strcmp (fname, "ssrc")) continue; if (!strcmp (fname, "timestamp-offset")) continue; if (!strcmp (fname, "seqnum-offset")) continue; if (g_str_has_prefix (fname, "srtp-")) continue; if (g_str_has_prefix (fname, "srtcp-")) continue; /* handled later */ if (g_str_has_prefix (fname, "x-gst-rtsp-server-rtx-time")) continue; if (!strcmp (fname, "a-framesize")) { /* a-framesize attribute */ if ((fval = gst_structure_get_string (s, fname))) { tmp = g_strdup_printf ("%d %s", caps_pt, fval); gst_sdp_media_add_attribute (smedia, fname + 2, tmp); g_free (tmp); } continue; } if (g_str_has_prefix (fname, "a-")) { /* attribute */ if ((fval = gst_structure_get_string (s, fname))) gst_sdp_media_add_attribute (smedia, fname + 2, fval); continue; } if (g_str_has_prefix (fname, "x-")) { /* attribute */ if ((fval = gst_structure_get_string (s, fname))) gst_sdp_media_add_attribute (smedia, fname, fval); continue; } if ((fval = gst_structure_get_string (s, fname))) { g_string_append_printf (fmtp, "%s%s=%s", first ? "" : ";", fname, fval); first = FALSE; } } if (!first) { tmp = g_string_free (fmtp, FALSE); gst_sdp_media_add_attribute (smedia, "fmtp", tmp); g_free (tmp); } else { g_string_free (fmtp, TRUE); } update_sdp_from_tags (stream, smedia); if ((rtx_time = gst_rtsp_stream_get_retransmission_time (stream))) { /* ssrc multiplexed retransmit functionality */ guint rtx_pt = gst_rtsp_stream_get_retransmission_pt (stream); if (rtx_pt == 0) { g_warning ("failed to find an available dynamic payload type. " "Not adding retransmission"); } else { gchar *tmp; tmp = g_strdup_printf ("%d", rtx_pt); gst_sdp_media_add_format (smedia, tmp); g_free (tmp); tmp = g_strdup_printf ("%d rtx/%d", rtx_pt, caps_rate); gst_sdp_media_add_attribute (smedia, "rtpmap", tmp); g_free (tmp); tmp = g_strdup_printf ("%d apt=%d;rtx-time=%" G_GINT64_FORMAT, rtx_pt, caps_pt, GST_TIME_AS_MSECONDS (rtx_time)); gst_sdp_media_add_attribute (smedia, "fmtp", tmp); g_free (tmp); } } gst_sdp_message_add_media (sdp, smedia); gst_sdp_media_free (smedia); return; /* ERRORS */ no_multicast: { gst_sdp_media_free (smedia); g_warning ("ignoring stream %d without multicast address", gst_rtsp_stream_get_index (stream)); return; } }
SDPMedia::SDPMedia() { gst_sdp_media_new(&media_); }
/** * gst_rtsp_sdp_from_media: * @sdp: a #GstSDPMessage * @info: info * @media: a #GstRTSPMedia * * Add @media specific info to @sdp. @info is used to configure the connection * information in the SDP. * * Returns: TRUE on success. */ gboolean gst_rtsp_sdp_from_media (GstSDPMessage * sdp, GstSDPInfo * info, GstRTSPMedia * media) { guint i, n_streams; gchar *rangestr; n_streams = gst_rtsp_media_n_streams (media); rangestr = gst_rtsp_media_get_range_string (media, FALSE, GST_RTSP_RANGE_NPT); if (rangestr == NULL) goto not_prepared; gst_sdp_message_add_attribute (sdp, "range", rangestr); g_free (rangestr); for (i = 0; i < n_streams; i++) { GstRTSPStream *stream; GstSDPMedia *smedia; GstStructure *s; const gchar *caps_str, *caps_enc, *caps_params; gchar *tmp; gint caps_pt, caps_rate; guint n_fields, j; gboolean first; GString *fmtp; GstCaps *caps; stream = gst_rtsp_media_get_stream (media, i); caps = gst_rtsp_stream_get_caps (stream); if (caps == NULL) { g_warning ("ignoring stream %d without media type", i); continue; } s = gst_caps_get_structure (caps, 0); if (s == NULL) { gst_caps_unref (caps); g_warning ("ignoring stream %d without media type", i); continue; } gst_sdp_media_new (&smedia); /* get media type and payload for the m= line */ caps_str = gst_structure_get_string (s, "media"); gst_sdp_media_set_media (smedia, caps_str); gst_structure_get_int (s, "payload", &caps_pt); tmp = g_strdup_printf ("%d", caps_pt); gst_sdp_media_add_format (smedia, tmp); g_free (tmp); gst_sdp_media_set_port_info (smedia, 0, 1); gst_sdp_media_set_proto (smedia, "RTP/AVP"); /* for the c= line */ if (info->is_ipv6) { gst_sdp_media_add_connection (smedia, "IN", "IP6", "::", 16, 0); } else { gst_sdp_media_add_connection (smedia, "IN", "IP4", "0.0.0.0", 16, 0); } /* get clock-rate, media type and params for the rtpmap attribute */ gst_structure_get_int (s, "clock-rate", &caps_rate); caps_enc = gst_structure_get_string (s, "encoding-name"); caps_params = gst_structure_get_string (s, "encoding-params"); if (caps_enc) { if (caps_params) tmp = g_strdup_printf ("%d %s/%d/%s", caps_pt, caps_enc, caps_rate, caps_params); else tmp = g_strdup_printf ("%d %s/%d", caps_pt, caps_enc, caps_rate); gst_sdp_media_add_attribute (smedia, "rtpmap", tmp); g_free (tmp); } /* the config uri */ tmp = gst_rtsp_stream_get_control (stream); gst_sdp_media_add_attribute (smedia, "control", tmp); g_free (tmp); /* collect all other properties and add them to fmtp or attributes */ fmtp = g_string_new (""); g_string_append_printf (fmtp, "%d ", caps_pt); first = TRUE; n_fields = gst_structure_n_fields (s); for (j = 0; j < n_fields; j++) { const gchar *fname, *fval; fname = gst_structure_nth_field_name (s, j); /* filter out standard properties */ if (!strcmp (fname, "media")) continue; if (!strcmp (fname, "payload")) continue; if (!strcmp (fname, "clock-rate")) continue; if (!strcmp (fname, "encoding-name")) continue; if (!strcmp (fname, "encoding-params")) continue; if (!strcmp (fname, "ssrc")) continue; if (!strcmp (fname, "clock-base")) continue; if (!strcmp (fname, "seqnum-base")) continue; if (g_str_has_prefix (fname, "a-")) { /* attribute */ if ((fval = gst_structure_get_string (s, fname))) gst_sdp_media_add_attribute (smedia, fname + 2, fval); continue; } if (g_str_has_prefix (fname, "x-")) { /* attribute */ if ((fval = gst_structure_get_string (s, fname))) gst_sdp_media_add_attribute (smedia, fname, fval); continue; } if ((fval = gst_structure_get_string (s, fname))) { g_string_append_printf (fmtp, "%s%s=%s", first ? "" : ";", fname, fval); first = FALSE; } } if (!first) { tmp = g_string_free (fmtp, FALSE); gst_sdp_media_add_attribute (smedia, "fmtp", tmp); g_free (tmp); } else { g_string_free (fmtp, TRUE); } update_sdp_from_tags (stream, smedia); gst_sdp_message_add_media (sdp, smedia); gst_sdp_media_free (smedia); gst_caps_unref (caps); } { GstNetTimeProvider *provider; if ((provider = gst_rtsp_media_get_time_provider (media, info->server_ip, 0))) { GstClock *clock; gchar *address, *str; gint port; g_object_get (provider, "clock", &clock, "address", &address, "port", &port, NULL); str = g_strdup_printf ("GstNetTimeProvider %s %s:%d %" G_GUINT64_FORMAT, g_type_name (G_TYPE_FROM_INSTANCE (clock)), address, port, gst_clock_get_time (clock)); gst_sdp_message_add_attribute (sdp, "x-gst-clock", str); g_free (str); gst_object_unref (clock); g_free (address); gst_object_unref (provider); } } return TRUE; /* ERRORS */ not_prepared: { GST_ERROR ("media %p is not prepared", media); return FALSE; } }
static gint create_and_send_ANNOUNCE_message2(GstRTSPsink* sink, GTimeVal *timeout, char **szSessionNumber) { const gchar *url_client_ip_str = "0.0.0.0";//"192.168.2.104"; const gchar *url_server_str_full = g_strdup_printf("rtsp://%s:%d/%s", sink->host, sink->port, sink->stream_name); //"rtsp://192.168.2.108:1935/live/1"; //conn = sink->conn; GstRTSPMessage msg = { 0 }; GstSDPMessage *sdp; GstRTSPMethod method; GstRTSPResult res; guint num_ports = 1; guint rtp_port = 5006; char *szPayloadType = g_strdup_printf("%d", sink->payload); method = GST_RTSP_ANNOUNCE ; res = gst_rtsp_message_init_request(&msg, method, url_server_str_full); if (res < 0) return res; /* set user-agent */ if (sink->user_agent) gst_rtsp_message_add_header(&msg, GST_RTSP_HDR_USER_AGENT, sink->user_agent); gst_rtsp_message_add_header(&msg, GST_RTSP_HDR_CONTENT_TYPE, "application/sdp"); // allocate sdp messege buffer... res = gst_sdp_message_new(&sdp); //v=.. res = gst_sdp_message_set_version(sdp, "0"); //o=... res = gst_sdp_message_set_origin(sdp, "-", "0", "0", "IN", "IP4", "0.0.0.0"); //s=.. if (sink->session_name) res = gst_sdp_message_set_session_name(sdp, "Unnamed"); //i=.. if (sink->information) res = gst_sdp_message_set_information(sdp, "N/A"); //c=... res = gst_sdp_message_set_connection(sdp, "IN", "IP4", url_client_ip_str, 0, 0); //a=... res = gst_sdp_message_add_attribute(sdp, "recvonly", NULL); // create media GstSDPMedia *media; res = gst_sdp_media_new(&media); res = gst_sdp_media_init(media); //m=... res = gst_sdp_media_set_media(media, "video"); res = gst_sdp_media_set_port_info(media, rtp_port, num_ports); res = gst_sdp_media_set_proto(media, "RTP/AVP"); res = gst_sdp_media_add_format(media, szPayloadType); //a=... char *rtpmap = g_strdup_printf("%s %s/%d", szPayloadType, sink->encoding_name, sink->clock_rate); res = gst_sdp_media_add_attribute(media, "rtpmap", rtpmap); res = gst_sdp_media_add_attribute(media, "fmtp", szPayloadType); res = gst_sdp_media_add_attribute(media, "control", "streamid=0"); // insert media into sdp res = gst_sdp_message_add_media(sdp, media); gchar * sdp_str = gst_sdp_message_as_text(sdp); int size = g_utf8_strlen(sdp_str, 500); gst_sdp_message_free(sdp); gst_sdp_media_free(media); res = gst_rtsp_message_set_body(&msg, sdp_str, size); sink->responce = &msg; // Send our packet receive server answer and check some basic checks. if ((res = sendReceiveAndCheck(sink->conn, timeout, &msg, sink->debug)) != GST_RTSP_OK) { return res; } // get session number *szSessionNumber = extractSessionNumberFromMessage(&msg); return GST_RTSP_OK; }