sjero.net Git - linphone/blob - coreapi/sal_eXosip2_sdp.c

   1 /*
   2 linphone
   3 Copyright (C) 2010  Simon MORLAT (simon.morlat@free.fr)
   4
   5 This program is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU General Public License
   7 as published by the Free Software Foundation; either version 2
   8 of the License, or (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18 */
  19
  20
  21 #include "ortp/b64.h"
  22 #include "ortp/ortp_srtp.h"
  23 #include "sal.h"
  24 #include <eXosip2/eXosip.h>
  25
  26 #define keywordcmp(key,b) strncmp(key,b,sizeof(key))
  27
  28 #ifdef FOR_LATER
  29
  30 static char *make_relay_session_id(const char *username, const char *relay){
  31         /*ideally this should be a hash of the parameters with a random part*/
  32         char tmp[128];
  33         int s1=(int)random();
  34         int s2=(int)random();
  35         long long int res=((long long int)s1)<<32 | (long long int) s2;
  36         void *src=&res;
  37         b64_encode(src, sizeof(long long int), tmp, sizeof(tmp));
  38         return osip_strdup(tmp);
  39 }
  40
  41
  42 static void add_relay_info(sdp_message_t *sdp, int mline, const char *relay, const char *relay_session_id){
  43
  44         if (relay) sdp_message_a_attribute_add(sdp, mline,
  45                                      osip_strdup ("relay-addr"),osip_strdup(relay));
  46         if (relay_session_id) sdp_message_a_attribute_add(sdp, mline,
  47                                      osip_strdup ("relay-session-id"), osip_strdup(relay_session_id));
  48 }
  49
  50 #endif
  51
  52 static char * int_2char(int a){
  53         char *p=osip_malloc(16);
  54         snprintf(p,16,"%i",a);
  55         return p;
  56 }
  57
  58 /* return the value of attr "field" for payload pt at line pos (field=rtpmap,fmtp...)*/
  59 static const char *sdp_message_a_attr_value_get_with_pt(sdp_message_t *sdp,int pos,int pt,const char *field)
  60 {
  61         int i,tmppt=0,scanned=0;
  62         char *tmp;
  63         sdp_attribute_t *attr;
  64         for (i=0;(attr=sdp_message_attribute_get(sdp,pos,i))!=NULL;i++){
  65                 if (keywordcmp(field,attr->a_att_field)==0 && attr->a_att_value!=NULL){
  66                         int nb = sscanf(attr->a_att_value,"%i %n",&tmppt,&scanned);
  67                         /* the return value may depend on how %n is interpreted by the libc: see manpage*/
  68                         if (nb == 1 || nb==2 ){
  69                                 if (pt==tmppt){
  70                                         tmp=attr->a_att_value+scanned;
  71                                         if (strlen(tmp)>0)
  72                                                 return tmp;
  73                                 }
  74                         }else ms_warning("sdp has a strange a= line (%s) nb=%i",attr->a_att_value,nb);
  75                 }
  76         }
  77         return NULL;
  78 }
  79
  80 #ifdef FOR_LATER
  81 /* return the value of attr "field" */
  82 static const char *sdp_message_a_attr_value_get(sdp_message_t *sdp,int pos,const char *field)
  83 {
  84         int i;
  85         sdp_attribute_t *attr;
  86         for (i=0;(attr=sdp_message_attribute_get(sdp,pos,i))!=NULL;i++){
  87                 if (keywordcmp(field,attr->a_att_field)==0 && attr->a_att_value!=NULL){
  88                         return attr->a_att_value;
  89                 }
  90         }
  91         return NULL;
  92 }
  93 #endif
  94
  95 static int _sdp_message_get_a_ptime(sdp_message_t *sdp, int mline){
  96         int i,ret;
  97         sdp_attribute_t *attr;
  98         for (i=0;(attr=sdp_message_attribute_get(sdp,mline,i))!=NULL;i++){
  99                 if (keywordcmp("ptime",attr->a_att_field)==0){
 100                         int nb = sscanf(attr->a_att_value,"%i",&ret);
 101                         /* the return value may depend on how %n is interpreted by the libc: see manpage*/
 102                         if (nb == 1){
 103                                 return ret;
 104                         }else ms_warning("sdp has a strange a=ptime line (%s) ",attr->a_att_value);
 105                 }
 106         }
 107         return 0;
 108 }
 109
 110 static int _sdp_message_get_mline_dir(sdp_message_t *sdp, int mline){
 111         int i;
 112         sdp_attribute_t *attr;
 113         for (i=0;(attr=sdp_message_attribute_get(sdp,mline,i))!=NULL;i++){
 114                 if (keywordcmp("sendrecv",attr->a_att_field)==0){
 115                         return SalStreamSendRecv;
 116                 }else if (keywordcmp("sendonly",attr->a_att_field)==0){
 117                         return SalStreamSendOnly;
 118                 }else if (keywordcmp("recvonly",attr->a_att_field)==0){
 119                         return SalStreamRecvOnly;
 120                 }else if (keywordcmp("inactive",attr->a_att_field)==0){
 121                         return SalStreamInactive;
 122                 }
 123         }
 124         return SalStreamSendRecv;
 125 }
 126
 127 static sdp_message_t *create_generic_sdp(const SalMediaDescription *desc)
 128 {
 129         sdp_message_t *local;
 130         int inet6;
 131         char sessid[16];
 132         char sessver[16];
 133         const char *rtp_addr = desc->addr;
 134
 135         snprintf(sessid,16,"%i",desc->session_id);
 136         snprintf(sessver,16,"%i",desc->session_ver);
 137         sdp_message_init (&local);
 138         if (strchr(desc->addr,':')!=NULL){
 139                 inet6=1;
 140         }else inet6=0;
 141         sdp_message_v_version_set (local, osip_strdup ("0"));
 142         sdp_message_o_origin_set (local, osip_strdup (desc->username),
 143                           osip_strdup (sessid), osip_strdup (sessver),
 144                           osip_strdup ("IN"), inet6 ? osip_strdup("IP6") : osip_strdup ("IP4"),
 145                           osip_strdup (desc->addr));
 146         sdp_message_s_name_set (local, osip_strdup ("Talk"));
 147         if(!sal_media_description_has_dir (desc,SalStreamSendOnly))
 148         {
 149                 sdp_message_c_connection_add (local, -1,
 150                                 osip_strdup ("IN"), inet6 ? osip_strdup ("IP6") : osip_strdup ("IP4"),
 151                                                 osip_strdup (rtp_addr), NULL, NULL);
 152         }
 153         else
 154         {
 155                 sdp_message_c_connection_add (local, -1,
 156                                 osip_strdup ("IN"), inet6 ? osip_strdup ("IP6") : osip_strdup ("IP4"),
 157                                                 inet6 ? osip_strdup ("::0") : osip_strdup ("0.0.0.0"), NULL, NULL);
 158         }
 159         sdp_message_t_time_descr_add (local, osip_strdup ("0"), osip_strdup ("0"));
 160         if (desc->bandwidth>0) sdp_message_b_bandwidth_add (local, -1, osip_strdup ("AS"),
 161                         int_2char(desc->bandwidth));
 162         if (desc->ice_completed == TRUE) sdp_message_a_attribute_add(local, -1, osip_strdup("nortpproxy"), osip_strdup("yes"));
 163         if (desc->ice_pwd[0] != '\0') sdp_message_a_attribute_add(local, -1, osip_strdup("ice-pwd"), osip_strdup(desc->ice_pwd));
 164         if (desc->ice_ufrag[0] != '\0') sdp_message_a_attribute_add(local, -1, osip_strdup("ice-ufrag"), osip_strdup(desc->ice_ufrag));
 165
 166         return local;
 167 }
 168
 169
 170 static bool_t is_known_rtpmap(const PayloadType *pt){
 171         switch(payload_type_get_number(pt)){
 172                 case 0:
 173                 case 8:
 174                 case 3:
 175                 case 34:
 176                         return TRUE;
 177         }
 178         return FALSE;
 179 }
 180
 181 static void add_payload(sdp_message_t *msg, int line, const PayloadType *pt, bool_t strip_well_known_rtpmaps)
 182 {
 183         char attr[256];
 184         sdp_message_m_payload_add (msg,line, int_2char (payload_type_get_number(pt)));
 185
 186         if (!strip_well_known_rtpmaps || !is_known_rtpmap(pt)){
 187                 if (pt->channels>1)
 188                         snprintf (attr,sizeof(attr),"%i %s/%i/%i", payload_type_get_number(pt),
 189                                         pt->mime_type, pt->clock_rate,pt->channels);
 190                 else
 191                         snprintf (attr,sizeof(attr),"%i %s/%i", payload_type_get_number(pt),
 192                                         pt->mime_type, pt->clock_rate);
 193                 sdp_message_a_attribute_add (msg, line,
 194                                                  osip_strdup ("rtpmap"), osip_strdup(attr));
 195         }
 196
 197         if (pt->recv_fmtp != NULL)
 198         {
 199                 snprintf (attr,sizeof(attr),"%i %s", payload_type_get_number(pt),pt->recv_fmtp);
 200                 sdp_message_a_attribute_add (msg, line, osip_strdup ("fmtp"),
 201                                      osip_strdup(attr));
 202         }
 203 }
 204
 205 static void add_ice_candidates(sdp_message_t *msg, int lineno, const SalStreamDescription *desc)
 206 {
 207         char buffer[1024];
 208         const SalIceCandidate *candidate;
 209         int nb;
 210         int i;
 211
 212         for (i = 0; i < SAL_MEDIA_DESCRIPTION_MAX_ICE_CANDIDATES; i++) {
 213                 candidate = &desc->ice_candidates[i];
 214                 if ((candidate->addr[0] == '\0') || (candidate->port == 0)) break;
 215                 nb = snprintf(buffer, sizeof(buffer), "%s %u UDP %u %s %d typ %s",
 216                         candidate->foundation, candidate->componentID, candidate->priority, candidate->addr, candidate->port, candidate->type);
 217                 if (nb < 0) {
 218                         ms_error("Cannot add ICE candidate attribute!");
 219                         return;
 220                 }
 221                 if (candidate->raddr[0] != '\0') {
 222                         nb = snprintf(buffer + nb, sizeof(buffer) - nb, " raddr %s rport %d", candidate->raddr, candidate->rport);
 223                         if (nb < 0) {
 224                                 ms_error("Cannot add ICE candidate attribute!");
 225                                 return;
 226                         }
 227                 }
 228                 sdp_message_a_attribute_add(msg, lineno, osip_strdup("candidate"), osip_strdup(buffer));
 229         }
 230 }
 231
 232 static void add_ice_remote_candidates(sdp_message_t *msg, int lineno, const SalStreamDescription *desc)
 233 {
 234         char buffer[1024];
 235         char *ptr = buffer;
 236         const SalIceRemoteCandidate *candidate;
 237         int offset = 0;
 238         int i;
 239
 240         buffer[0] = '\0';
 241         for (i = 0; i < SAL_MEDIA_DESCRIPTION_MAX_ICE_REMOTE_CANDIDATES; i++) {
 242                 candidate = &desc->ice_remote_candidates[i];
 243                 if ((candidate->addr[0] != '\0') && (candidate->port != 0)) {
 244                         offset = snprintf(ptr, buffer + sizeof(buffer) - ptr, "%s%d %s %d", (i > 0) ? " " : "", i + 1, candidate->addr, candidate->port);
 245                         if (offset < 0) {
 246                                 ms_error("Cannot add ICE remote-candidates attribute!");
 247                                 return;
 248                         }
 249                         ptr += offset;
 250                 }
 251         }
 252         if (buffer[0] != '\0') sdp_message_a_attribute_add(msg, lineno, osip_strdup("remote-candidates"), osip_strdup(buffer));
 253 }
 254
 255 static void add_line(sdp_message_t *msg, int lineno, const SalStreamDescription *desc){
 256         const char *mt=NULL;
 257         const MSList *elem;
 258         const char *rtp_addr;
 259         const char *rtcp_addr;
 260         const char *dir="sendrecv";
 261         int rtp_port;
 262         int rtcp_port;
 263         bool_t strip_well_known_rtpmaps;
 264         bool_t different_rtp_and_rtcp_addr;
 265
 266         switch (desc->type) {
 267         case SalAudio:
 268                 mt="audio";
 269                 break;
 270         case SalVideo:
 271                 mt="video";
 272                 break;
 273         case SalOther:
 274                 mt=desc->typeother;
 275                 break;
 276         }
 277         rtp_addr=desc->rtp_addr;
 278         rtcp_addr=desc->rtcp_addr;
 279         rtp_port=desc->rtp_port;
 280         rtcp_port=desc->rtcp_port;
 281         if (desc->candidates[0].addr[0]!='\0'){
 282                 rtp_addr=desc->candidates[0].addr;
 283                 rtp_port=desc->candidates[0].port;
 284         }
 285
 286         if (desc->proto == SalProtoRtpSavp) {
 287                 int i;
 288
 289                 sdp_message_m_media_add (msg, osip_strdup (mt),
 290                                          int_2char (rtp_port), NULL,
 291                                          osip_strdup ("RTP/SAVP"));
 292
 293                 /* add crypto lines */
 294                 for(i=0; i<SAL_CRYPTO_ALGO_MAX; i++) {
 295                         char buffer[1024];
 296                         switch (desc->crypto[i].algo) {
 297                                 case AES_128_SHA1_80:
 298                                         snprintf(buffer, 1024, "%d %s inline:%s",
 299                                                 desc->crypto[i].tag, "AES_CM_128_HMAC_SHA1_80", desc->crypto[i].master_key);
 300                                         sdp_message_a_attribute_add(msg, lineno, osip_strdup("crypto"),
 301                                                 osip_strdup(buffer));
 302                                         break;
 303                                 case AES_128_SHA1_32:
 304                                         snprintf(buffer, 1024, "%d %s inline:%s",
 305                                                 desc->crypto[i].tag, "AES_CM_128_HMAC_SHA1_32", desc->crypto[i].master_key);
 306                                         sdp_message_a_attribute_add(msg, lineno, osip_strdup("crypto"),
 307                                                 osip_strdup(buffer));
 308                                         break;
 309                                 case AES_128_NO_AUTH:
 310                                         ms_warning("Unsupported crypto suite: AES_128_NO_AUTH");
 311                                         break;
 312                                 case NO_CIPHER_SHA1_80:
 313                                         ms_warning("Unsupported crypto suite: NO_CIPHER_SHA1_80");
 314                                         break;
 315                                 default:
 316                                         i = SAL_CRYPTO_ALGO_MAX;
 317                         }
 318                 }
 319
 320         } else {
 321                 sdp_message_m_media_add (msg, osip_strdup (mt),
 322                                          int_2char (rtp_port), NULL,
 323                                          osip_strdup ("RTP/AVP"));
 324
 325         }
 326
 327         /*only add a c= line within the stream description if address are differents*/
 328         if (rtp_addr[0]!='\0' && strcmp(rtp_addr,sdp_message_c_addr_get(msg, -1, 0))!=0){
 329                 bool_t inet6;
 330                 if (strchr(rtp_addr,':')!=NULL){
 331                         inet6=TRUE;
 332                 }else inet6=FALSE;
 333                 sdp_message_c_connection_add (msg, lineno,
 334                               osip_strdup ("IN"), inet6 ? osip_strdup ("IP6") : osip_strdup ("IP4"),
 335                               osip_strdup (rtp_addr), NULL, NULL);
 336         }
 337
 338         if (desc->bandwidth>0) sdp_message_b_bandwidth_add (msg, lineno, osip_strdup ("AS"),
 339                                      int_2char(desc->bandwidth));
 340         if (desc->ptime>0) sdp_message_a_attribute_add(msg,lineno,osip_strdup("ptime"),
 341                                 int_2char(desc->ptime));
 342         strip_well_known_rtpmaps=ms_list_size(desc->payloads)>5;
 343         if (desc->payloads){
 344                 for(elem=desc->payloads;elem!=NULL;elem=elem->next){
 345                         add_payload(msg, lineno, (PayloadType*)elem->data,strip_well_known_rtpmaps);
 346                 }
 347         }else{
 348                 /* to comply with SDP we cannot have an empty payload type number list */
 349                 /* as it happens only when mline is declined with a zero port, it does not matter to put whatever codec*/
 350                 sdp_message_m_payload_add (msg,lineno, int_2char (0));
 351         }
 352         switch(desc->dir){
 353                 case SalStreamSendRecv:
 354                         /*dir="sendrecv";*/
 355                         dir=NULL;
 356                 break;
 357                 case SalStreamRecvOnly:
 358                         dir="recvonly";
 359                         break;
 360                 case SalStreamSendOnly:
 361                         dir="sendonly";
 362                         break;
 363                 case SalStreamInactive:
 364                         dir="inactive";
 365                         break;
 366         }
 367         if (dir) sdp_message_a_attribute_add (msg, lineno, osip_strdup (dir),NULL);
 368         if (rtp_port != 0) {
 369                 different_rtp_and_rtcp_addr = (rtcp_addr[0] != '\0') && (strcmp(rtp_addr, rtcp_addr) != 0);
 370                 if ((rtcp_port != (rtp_port + 1)) || (different_rtp_and_rtcp_addr == TRUE)) {
 371                         if (different_rtp_and_rtcp_addr == TRUE) {
 372                                 char buffer[1024];
 373                                 snprintf(buffer, sizeof(buffer), "%u IN IP4 %s", rtcp_port, rtcp_addr);
 374                                 sdp_message_a_attribute_add(msg, lineno, osip_strdup("rtcp"), osip_strdup(buffer));
 375                         } else {
 376                                 sdp_message_a_attribute_add(msg, lineno, osip_strdup("rtcp"), int_2char(rtcp_port));
 377                         }
 378                 }
 379         }
 380         if (desc->ice_mismatch == TRUE) {
 381                 sdp_message_a_attribute_add(msg, lineno, osip_strdup("ice-mismatch"), NULL);
 382         } else {
 383                 if (desc->ice_pwd[0] != '\0') sdp_message_a_attribute_add(msg, lineno, osip_strdup("ice-pwd"), osip_strdup(desc->ice_pwd));
 384                 if (desc->ice_ufrag[0] != '\0') sdp_message_a_attribute_add(msg, lineno, osip_strdup("ice-ufrag"), osip_strdup(desc->ice_ufrag));
 385                 add_ice_candidates(msg, lineno, desc);
 386                 add_ice_remote_candidates(msg, lineno, desc);
 387         }
 388 }
 389
 390
 391 sdp_message_t *media_description_to_sdp(const SalMediaDescription *desc){
 392         int i;
 393         sdp_message_t *msg=create_generic_sdp(desc);
 394         for(i=0;i<desc->nstreams;++i){
 395                 add_line(msg,i,&desc->streams[i]);
 396         }
 397         return msg;
 398 }
 399
 400 static int payload_type_fill_from_rtpmap(PayloadType *pt, const char *rtpmap){
 401         if (rtpmap==NULL){
 402                 PayloadType *refpt=rtp_profile_get_payload(&av_profile,payload_type_get_number(pt));
 403                 if (refpt){
 404                         pt->mime_type=ms_strdup(refpt->mime_type);
 405                         pt->clock_rate=refpt->clock_rate;
 406                 }else{
 407                         ms_error("payload number %i has no rtpmap and is unknown in AV Profile, ignored.",
 408                             payload_type_get_number(pt));
 409                         return -1;
 410                 }
 411         }else{
 412                 char *mime=ms_strdup(rtpmap);
 413                 char *p=strchr(mime,'/');
 414                 if (p){
 415                         char *chans;
 416                         *p='\0';
 417                         p++;
 418                         chans=strchr(p,'/');
 419                         if (chans){
 420                                 *chans='\0';
 421                                 chans++;
 422                                 pt->channels=atoi(chans);
 423                         }else pt->channels=1;
 424                         pt->clock_rate=atoi(p);
 425                 }
 426                 pt->mime_type=mime;
 427         }
 428         return 0;
 429 }
 430
 431 int sdp_to_media_description(sdp_message_t *msg, SalMediaDescription *desc){
 432         int i,j;
 433         const char *mtype,*proto,*rtp_port,*rtp_addr,*number;
 434         sdp_bandwidth_t *sbw=NULL;
 435         sdp_attribute_t *attr;
 436         int nb_ice_candidates;
 437
 438         rtp_addr=sdp_message_c_addr_get (msg, -1, 0);
 439         if (rtp_addr)
 440                 strncpy(desc->addr,rtp_addr,sizeof(desc->addr));
 441         for(j=0;(sbw=sdp_message_bandwidth_get(msg,-1,j))!=NULL;++j){
 442                 if (strcasecmp(sbw->b_bwtype,"AS")==0) desc->bandwidth=atoi(sbw->b_bandwidth);
 443         }
 444
 445         /* Get ICE remote ufrag and remote pwd, and ice_lite flag */
 446         for (i = 0; (i < SAL_MEDIA_DESCRIPTION_MAX_MESSAGE_ATTRIBUTES) && ((attr = sdp_message_attribute_get(msg, -1, i)) != NULL); i++) {
 447                 if ((keywordcmp("ice-ufrag", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 448                         strncpy(desc->ice_ufrag, attr->a_att_value, sizeof(desc->ice_ufrag));
 449                 } else if ((keywordcmp("ice-pwd", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 450                         strncpy(desc->ice_pwd, attr->a_att_value, sizeof(desc->ice_pwd));
 451                 } else if (keywordcmp("ice-lite", attr->a_att_field) == 0) {
 452                         desc->ice_lite = TRUE;
 453                 }
 454         }
 455
 456         /* for each m= line */
 457         for (i=0; !sdp_message_endof_media (msg, i) && i<SAL_MEDIA_DESCRIPTION_MAX_STREAMS; i++)
 458         {
 459                 SalStreamDescription *stream=&desc->streams[i];
 460                 nb_ice_candidates = 0;
 461
 462                 memset(stream,0,sizeof(*stream));
 463                 mtype = sdp_message_m_media_get(msg, i);
 464                 proto = sdp_message_m_proto_get (msg, i);
 465                 rtp_port = sdp_message_m_port_get(msg, i);
 466                 stream->proto=SalProtoUnknown;
 467                 if (proto){
 468                         if (strcasecmp(proto,"RTP/AVP")==0)
 469                                 stream->proto=SalProtoRtpAvp;
 470                         else if (strcasecmp(proto,"RTP/SAVP")==0){
 471                                 stream->proto=SalProtoRtpSavp;
 472                         }
 473                 }
 474                 rtp_addr = sdp_message_c_addr_get (msg, i, 0);
 475                 if (rtp_addr != NULL)
 476                         strncpy(stream->rtp_addr,rtp_addr,sizeof(stream->rtp_addr));
 477                 if (rtp_port)
 478                         stream->rtp_port=atoi(rtp_port);
 479
 480                 stream->ptime=_sdp_message_get_a_ptime(msg,i);
 481                 if (strcasecmp("audio", mtype) == 0){
 482                         stream->type=SalAudio;
 483                 }else if (strcasecmp("video", mtype) == 0){
 484                         stream->type=SalVideo;
 485                 }else {
 486                         stream->type=SalOther;
 487                         strncpy(stream->typeother,mtype,sizeof(stream->typeother)-1);
 488                 }
 489                 for(j=0;(sbw=sdp_message_bandwidth_get(msg,i,j))!=NULL;++j){
 490                         if (strcasecmp(sbw->b_bwtype,"AS")==0) stream->bandwidth=atoi(sbw->b_bandwidth);
 491                 }
 492                 stream->dir=_sdp_message_get_mline_dir(msg,i);
 493                 /* for each payload type */
 494                 for (j=0;((number=sdp_message_m_payload_get (msg, i,j)) != NULL); j++){
 495                         const char *rtpmap,*fmtp;
 496                         int ptn=atoi(number);
 497                         PayloadType *pt=payload_type_new();
 498                         payload_type_set_number(pt,ptn);
 499                         /* get the rtpmap associated to this codec, if any */
 500                         rtpmap=sdp_message_a_attr_value_get_with_pt(msg, i,ptn,"rtpmap");
 501                         if (payload_type_fill_from_rtpmap(pt,rtpmap)==0){
 502                                 /* get the fmtp, if any */
 503                                 fmtp=sdp_message_a_attr_value_get_with_pt(msg, i, ptn,"fmtp");
 504                                 payload_type_set_send_fmtp(pt,fmtp);
 505                                 stream->payloads=ms_list_append(stream->payloads,pt);
 506                                 ms_message("Found payload %s/%i fmtp=%s",pt->mime_type,pt->clock_rate,
 507                                         pt->send_fmtp ? pt->send_fmtp : "");
 508                         }
 509                 }
 510
 511                 /* Get media specific RTCP attribute */
 512                 stream->rtcp_port = stream->rtp_port + 1;
 513                 snprintf(stream->rtcp_addr, sizeof(stream->rtcp_addr), stream->rtp_addr);
 514                 for (j = 0; ((attr = sdp_message_attribute_get(msg, i, j)) != NULL); j++) {
 515                         if ((keywordcmp("rtcp", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 516                                 char tmp[256];
 517                                 int nb = sscanf(attr->a_att_value, "%d IN IP4 %s", &stream->rtcp_port, tmp);
 518                                 if (nb == 1) {
 519                                         /* SDP rtcp attribute only contains the port */
 520                                 } else if (nb == 2) {
 521                                         strncpy(stream->rtcp_addr, tmp, sizeof(stream->rtcp_addr));
 522                                 } else {
 523                                         ms_warning("sdp has a strange a= line (%s) nb=%i", attr->a_att_value, nb);
 524                                 }
 525                         }
 526                 }
 527
 528                 /* read crypto lines if any */
 529                 if (stream->proto == SalProtoRtpSavp) {
 530                         int k, valid_count = 0;
 531
 532                         memset(&stream->crypto, 0, sizeof(stream->crypto));
 533                         for (k=0;valid_count < SAL_CRYPTO_ALGO_MAX && (attr=sdp_message_attribute_get(msg,i,k))!=NULL;k++){
 534                                 char tmp[256], tmp2[256];
 535                                 if (keywordcmp("crypto",attr->a_att_field)==0 && attr->a_att_value!=NULL){
 536                                         int nb = sscanf(attr->a_att_value, "%d %256s inline:%256s",
 537                                                 &stream->crypto[valid_count].tag,
 538                                                 tmp,
 539                                                 tmp2);
 540                                                 ms_message("Found valid crypto line (tag:%d algo:'%s' key:'%s'",
 541                                                                 stream->crypto[valid_count].tag,
 542                                                                 tmp,
 543                                                                 tmp2);
 544                                         if (nb == 3) {
 545                                                 if (strcmp(tmp, "AES_CM_128_HMAC_SHA1_80") == 0)
 546                                                         stream->crypto[valid_count].algo = AES_128_SHA1_80;
 547                                                 else if (strcmp(tmp, "AES_CM_128_HMAC_SHA1_32") == 0)
 548                                                         stream->crypto[valid_count].algo = AES_128_SHA1_32;
 549                                                 else {
 550                                                         ms_warning("Failed to parse crypto-algo: '%s'", tmp);
 551                                                         stream->crypto[valid_count].algo = 0;
 552                                                 }
 553                                                 if (stream->crypto[valid_count].algo) {
 554                                                         strncpy(stream->crypto[valid_count].master_key, tmp2, 41);
 555                                                         stream->crypto[valid_count].master_key[40] = '\0';
 556                                                         ms_message("Found valid crypto line (tag:%d algo:'%s' key:'%s'",
 557                                                                 stream->crypto[valid_count].tag,
 558                                                                 tmp,
 559                                                                 stream->crypto[valid_count].master_key);
 560                                                         valid_count++;
 561                                                 }
 562                                         } else {
 563                                                 ms_warning("sdp has a strange a= line (%s) nb=%i",attr->a_att_value,nb);
 564                                         }
 565                                 }
 566                         }
 567                         ms_message("Found: %d valid crypto lines", valid_count);
 568                 }
 569
 570                 /* Get ICE candidate attributes if any */
 571                 for (j = 0; (attr = sdp_message_attribute_get(msg, i, j)) != NULL; j++) {
 572                         if ((keywordcmp("candidate", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 573                                 SalIceCandidate *candidate = &stream->ice_candidates[nb_ice_candidates];
 574                                 int nb = sscanf(attr->a_att_value, "%s %u UDP %u %s %d typ %s raddr %s rport %d",
 575                                         candidate->foundation, &candidate->componentID, &candidate->priority, candidate->addr, &candidate->port,
 576                                         candidate->type, candidate->raddr, &candidate->rport);
 577                                 if ((nb == 6) || (nb == 8)) nb_ice_candidates++;
 578                                 else memset(candidate, 0, sizeof(*candidate));
 579                         } else if ((keywordcmp("remote-candidates", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 580                                 SalIceRemoteCandidate candidate;
 581                                 unsigned int componentID;
 582                                 int offset;
 583                                 char *ptr = attr->a_att_value;
 584                                 while (3 == sscanf(ptr, "%u %s %u%n", &componentID, candidate.addr, &candidate.port, &offset)) {
 585                                         if ((componentID > 0) && (componentID <= SAL_MEDIA_DESCRIPTION_MAX_ICE_REMOTE_CANDIDATES)) {
 586                                                 SalIceRemoteCandidate *remote_candidate = &stream->ice_remote_candidates[componentID - 1];
 587                                                 strncpy(remote_candidate->addr, candidate.addr, sizeof(remote_candidate->addr));
 588                                                 remote_candidate->port = candidate.port;
 589                                         }
 590                                         ptr += offset;
 591                                         if (ptr[offset] == ' ') ptr += 1;
 592                                 }
 593                         } else if ((keywordcmp("ice-ufrag", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 594                                 strncpy(stream->ice_ufrag, attr->a_att_value, sizeof(stream->ice_ufrag));
 595                         } else if ((keywordcmp("ice-pwd", attr->a_att_field) == 0) && (attr->a_att_value != NULL)) {
 596                                 strncpy(stream->ice_pwd, attr->a_att_value, sizeof(stream->ice_pwd));
 597                         } else if (keywordcmp("ice-mismatch", attr->a_att_field) == 0) {
 598                                 stream->ice_mismatch = TRUE;
 599                         }
 600                 }
 601         }
 602         desc->nstreams=i;
 603         return 0;
 604 }