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1 /***************************************************************************
2  *                                  _   _ ____  _
3  *  Project                     ___| | | |  _ \| |
4  *                             / __| | | | |_) | |
5  *                            | (__| |_| |  _ <| |___
6  *                             \___|\___/|_| \_\_____|
7  *
8  * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
9  *
10  * This software is licensed as described in the file COPYING, which
11  * you should have received as part of this distribution. The terms
12  * are also available at http://curl.haxx.se/docs/copyright.html.
13  *
14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15  * copies of the Software, and permit persons to whom the Software is
16  * furnished to do so, under the terms of the COPYING file.
17  *
18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19  * KIND, either express or implied.
20  *
21  ***************************************************************************/
22 
23 #include "curl_setup.h"
24 
25 #ifndef CURL_DISABLE_RTSP
26 
27 #include "urldata.h"
28 #include <curl/curl.h>
29 #include "transfer.h"
30 #include "sendf.h"
31 #include "multiif.h"
32 #include "http.h"
33 #include "url.h"
34 #include "progress.h"
35 #include "rtsp.h"
36 #include "rawstr.h"
37 #include "select.h"
38 #include "connect.h"
39 #include "curl_printf.h"
40 
41 /* The last #include files should be: */
42 #include "curl_memory.h"
43 #include "memdebug.h"
44 
45 /*
46  * TODO (general)
47  *  -incoming server requests
48  *      -server CSeq counter
49  *  -digest authentication
50  *  -connect thru proxy
51  *  -pipelining?
52  */
53 
54 
55 #define RTP_PKT_CHANNEL(p)   ((int)((unsigned char)((p)[1])))
56 
57 #define RTP_PKT_LENGTH(p)  ((((int)((unsigned char)((p)[2]))) << 8) | \
58                              ((int)((unsigned char)((p)[3]))))
59 
60 /* protocol-specific functions set up to be called by the main engine */
61 static CURLcode rtsp_do(struct connectdata *conn, bool *done);
62 static CURLcode rtsp_done(struct connectdata *conn, CURLcode, bool premature);
63 static CURLcode rtsp_connect(struct connectdata *conn, bool *done);
64 static CURLcode rtsp_disconnect(struct connectdata *conn, bool dead);
65 
66 static int rtsp_getsock_do(struct connectdata *conn,
67                            curl_socket_t *socks,
68                            int numsocks);
69 
70 /*
71  * Parse and write out any available RTP data.
72  *
73  * nread: amount of data left after k->str. will be modified if RTP
74  *        data is parsed and k->str is moved up
75  * readmore: whether or not the RTP parser needs more data right away
76  */
77 static CURLcode rtsp_rtp_readwrite(struct SessionHandle *data,
78                                    struct connectdata *conn,
79                                    ssize_t *nread,
80                                    bool *readmore);
81 
82 static CURLcode rtsp_setup_connection(struct connectdata *conn);
83 
84 
85 /* this returns the socket to wait for in the DO and DOING state for the multi
86    interface and then we're always _sending_ a request and thus we wait for
87    the single socket to become writable only */
rtsp_getsock_do(struct connectdata * conn,curl_socket_t * socks,int numsocks)88 static int rtsp_getsock_do(struct connectdata *conn,
89                            curl_socket_t *socks,
90                            int numsocks)
91 {
92   /* write mode */
93   (void)numsocks; /* unused, we trust it to be at least 1 */
94   socks[0] = conn->sock[FIRSTSOCKET];
95   return GETSOCK_WRITESOCK(0);
96 }
97 
98 static
99 CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len);
100 
101 
102 /*
103  * RTSP handler interface.
104  */
105 const struct Curl_handler Curl_handler_rtsp = {
106   "RTSP",                               /* scheme */
107   rtsp_setup_connection,                /* setup_connection */
108   rtsp_do,                              /* do_it */
109   rtsp_done,                            /* done */
110   ZERO_NULL,                            /* do_more */
111   rtsp_connect,                         /* connect_it */
112   ZERO_NULL,                            /* connecting */
113   ZERO_NULL,                            /* doing */
114   ZERO_NULL,                            /* proto_getsock */
115   rtsp_getsock_do,                      /* doing_getsock */
116   ZERO_NULL,                            /* domore_getsock */
117   ZERO_NULL,                            /* perform_getsock */
118   rtsp_disconnect,                      /* disconnect */
119   rtsp_rtp_readwrite,                   /* readwrite */
120   PORT_RTSP,                            /* defport */
121   CURLPROTO_RTSP,                       /* protocol */
122   PROTOPT_NONE                          /* flags */
123 };
124 
125 
rtsp_setup_connection(struct connectdata * conn)126 static CURLcode rtsp_setup_connection(struct connectdata *conn)
127 {
128   struct RTSP *rtsp;
129 
130   conn->data->req.protop = rtsp = calloc(1, sizeof(struct RTSP));
131   if(!rtsp)
132     return CURLE_OUT_OF_MEMORY;
133 
134   return CURLE_OK;
135 }
136 
137 
138 /*
139  * The server may send us RTP data at any point, and RTSPREQ_RECEIVE does not
140  * want to block the application forever while receiving a stream. Therefore,
141  * we cannot assume that an RTSP socket is dead just because it is readable.
142  *
143  * Instead, if it is readable, run Curl_getconnectinfo() to peek at the socket
144  * and distinguish between closed and data.
145  */
Curl_rtsp_connisdead(struct connectdata * check)146 bool Curl_rtsp_connisdead(struct connectdata *check)
147 {
148   int sval;
149   bool ret_val = TRUE;
150 
151   sval = Curl_socket_ready(check->sock[FIRSTSOCKET], CURL_SOCKET_BAD, 0);
152   if(sval == 0) {
153     /* timeout */
154     ret_val = FALSE;
155   }
156   else if(sval & CURL_CSELECT_ERR) {
157     /* socket is in an error state */
158     ret_val = TRUE;
159   }
160   else if((sval & CURL_CSELECT_IN) && check->data) {
161     /* readable with no error. could be closed or could be alive but we can
162        only check if we have a proper SessionHandle for the connection */
163     curl_socket_t connectinfo = Curl_getconnectinfo(check->data, &check);
164     if(connectinfo != CURL_SOCKET_BAD)
165       ret_val = FALSE;
166   }
167 
168   return ret_val;
169 }
170 
rtsp_connect(struct connectdata * conn,bool * done)171 static CURLcode rtsp_connect(struct connectdata *conn, bool *done)
172 {
173   CURLcode httpStatus;
174   struct SessionHandle *data = conn->data;
175 
176   httpStatus = Curl_http_connect(conn, done);
177 
178   /* Initialize the CSeq if not already done */
179   if(data->state.rtsp_next_client_CSeq == 0)
180     data->state.rtsp_next_client_CSeq = 1;
181   if(data->state.rtsp_next_server_CSeq == 0)
182     data->state.rtsp_next_server_CSeq = 1;
183 
184   conn->proto.rtspc.rtp_channel = -1;
185 
186   return httpStatus;
187 }
188 
rtsp_disconnect(struct connectdata * conn,bool dead)189 static CURLcode rtsp_disconnect(struct connectdata *conn, bool dead)
190 {
191   (void) dead;
192   Curl_safefree(conn->proto.rtspc.rtp_buf);
193   return CURLE_OK;
194 }
195 
196 
rtsp_done(struct connectdata * conn,CURLcode status,bool premature)197 static CURLcode rtsp_done(struct connectdata *conn,
198                           CURLcode status, bool premature)
199 {
200   struct SessionHandle *data = conn->data;
201   struct RTSP *rtsp = data->req.protop;
202   CURLcode httpStatus;
203   long CSeq_sent;
204   long CSeq_recv;
205 
206   /* Bypass HTTP empty-reply checks on receive */
207   if(data->set.rtspreq == RTSPREQ_RECEIVE)
208     premature = TRUE;
209 
210   httpStatus = Curl_http_done(conn, status, premature);
211 
212   if(rtsp) {
213     /* Check the sequence numbers */
214     CSeq_sent = rtsp->CSeq_sent;
215     CSeq_recv = rtsp->CSeq_recv;
216     if((data->set.rtspreq != RTSPREQ_RECEIVE) && (CSeq_sent != CSeq_recv)) {
217       failf(data,
218             "The CSeq of this request %ld did not match the response %ld",
219             CSeq_sent, CSeq_recv);
220       return CURLE_RTSP_CSEQ_ERROR;
221     }
222     else if(data->set.rtspreq == RTSPREQ_RECEIVE &&
223             (conn->proto.rtspc.rtp_channel == -1)) {
224       infof(data, "Got an RTP Receive with a CSeq of %ld\n", CSeq_recv);
225       /* TODO CPC: Server -> Client logic here */
226     }
227   }
228 
229   return httpStatus;
230 }
231 
rtsp_do(struct connectdata * conn,bool * done)232 static CURLcode rtsp_do(struct connectdata *conn, bool *done)
233 {
234   struct SessionHandle *data = conn->data;
235   CURLcode result=CURLE_OK;
236   Curl_RtspReq rtspreq = data->set.rtspreq;
237   struct RTSP *rtsp = data->req.protop;
238   struct HTTP *http;
239   Curl_send_buffer *req_buffer;
240   curl_off_t postsize = 0; /* for ANNOUNCE and SET_PARAMETER */
241   curl_off_t putsize = 0; /* for ANNOUNCE and SET_PARAMETER */
242 
243   const char *p_request = NULL;
244   const char *p_session_id = NULL;
245   const char *p_accept = NULL;
246   const char *p_accept_encoding = NULL;
247   const char *p_range = NULL;
248   const char *p_referrer = NULL;
249   const char *p_stream_uri = NULL;
250   const char *p_transport = NULL;
251   const char *p_uagent = NULL;
252 
253   *done = TRUE;
254 
255   http = &(rtsp->http_wrapper);
256   /* Assert that no one has changed the RTSP struct in an evil way */
257   DEBUGASSERT((void *)http == (void *)rtsp);
258 
259   rtsp->CSeq_sent = data->state.rtsp_next_client_CSeq;
260   rtsp->CSeq_recv = 0;
261 
262   /* Setup the 'p_request' pointer to the proper p_request string
263    * Since all RTSP requests are included here, there is no need to
264    * support custom requests like HTTP.
265    **/
266   data->set.opt_no_body = TRUE; /* most requests don't contain a body */
267   switch(rtspreq) {
268   default:
269     failf(data, "Got invalid RTSP request");
270     return CURLE_BAD_FUNCTION_ARGUMENT;
271   case RTSPREQ_OPTIONS:
272     p_request = "OPTIONS";
273     break;
274   case RTSPREQ_DESCRIBE:
275     p_request = "DESCRIBE";
276     data->set.opt_no_body = FALSE;
277     break;
278   case RTSPREQ_ANNOUNCE:
279     p_request = "ANNOUNCE";
280     break;
281   case RTSPREQ_SETUP:
282     p_request = "SETUP";
283     break;
284   case RTSPREQ_PLAY:
285     p_request = "PLAY";
286     break;
287   case RTSPREQ_PAUSE:
288     p_request = "PAUSE";
289     break;
290   case RTSPREQ_TEARDOWN:
291     p_request = "TEARDOWN";
292     break;
293   case RTSPREQ_GET_PARAMETER:
294     /* GET_PARAMETER's no_body status is determined later */
295     p_request = "GET_PARAMETER";
296     data->set.opt_no_body = FALSE;
297     break;
298   case RTSPREQ_SET_PARAMETER:
299     p_request = "SET_PARAMETER";
300     break;
301   case RTSPREQ_RECORD:
302     p_request = "RECORD";
303     break;
304   case RTSPREQ_RECEIVE:
305     p_request = "";
306     /* Treat interleaved RTP as body*/
307     data->set.opt_no_body = FALSE;
308     break;
309   case RTSPREQ_LAST:
310     failf(data, "Got invalid RTSP request: RTSPREQ_LAST");
311     return CURLE_BAD_FUNCTION_ARGUMENT;
312   }
313 
314   if(rtspreq == RTSPREQ_RECEIVE) {
315     Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE,
316                         &http->readbytecount, -1, NULL);
317 
318     return result;
319   }
320 
321   p_session_id = data->set.str[STRING_RTSP_SESSION_ID];
322   if(!p_session_id &&
323      (rtspreq & ~(RTSPREQ_OPTIONS | RTSPREQ_DESCRIBE | RTSPREQ_SETUP))) {
324     failf(data, "Refusing to issue an RTSP request [%s] without a session ID.",
325           p_request);
326     return CURLE_BAD_FUNCTION_ARGUMENT;
327   }
328 
329   /* TODO: auth? */
330   /* TODO: proxy? */
331 
332   /* Stream URI. Default to server '*' if not specified */
333   if(data->set.str[STRING_RTSP_STREAM_URI]) {
334     p_stream_uri = data->set.str[STRING_RTSP_STREAM_URI];
335   }
336   else {
337     p_stream_uri = "*";
338   }
339 
340   /* Transport Header for SETUP requests */
341   p_transport = Curl_checkheaders(conn, "Transport:");
342   if(rtspreq == RTSPREQ_SETUP && !p_transport) {
343     /* New Transport: setting? */
344     if(data->set.str[STRING_RTSP_TRANSPORT]) {
345       Curl_safefree(conn->allocptr.rtsp_transport);
346 
347       conn->allocptr.rtsp_transport =
348         aprintf("Transport: %s\r\n",
349                 data->set.str[STRING_RTSP_TRANSPORT]);
350       if(!conn->allocptr.rtsp_transport)
351         return CURLE_OUT_OF_MEMORY;
352     }
353     else {
354       failf(data,
355             "Refusing to issue an RTSP SETUP without a Transport: header.");
356       return CURLE_BAD_FUNCTION_ARGUMENT;
357     }
358 
359     p_transport = conn->allocptr.rtsp_transport;
360   }
361 
362   /* Accept Headers for DESCRIBE requests */
363   if(rtspreq == RTSPREQ_DESCRIBE) {
364     /* Accept Header */
365     p_accept = Curl_checkheaders(conn, "Accept:")?
366       NULL:"Accept: application/sdp\r\n";
367 
368     /* Accept-Encoding header */
369     if(!Curl_checkheaders(conn, "Accept-Encoding:") &&
370        data->set.str[STRING_ENCODING]) {
371       Curl_safefree(conn->allocptr.accept_encoding);
372       conn->allocptr.accept_encoding =
373         aprintf("Accept-Encoding: %s\r\n", data->set.str[STRING_ENCODING]);
374 
375       if(!conn->allocptr.accept_encoding)
376         return CURLE_OUT_OF_MEMORY;
377 
378       p_accept_encoding = conn->allocptr.accept_encoding;
379     }
380   }
381 
382   /* The User-Agent string might have been allocated in url.c already, because
383      it might have been used in the proxy connect, but if we have got a header
384      with the user-agent string specified, we erase the previously made string
385      here. */
386   if(Curl_checkheaders(conn, "User-Agent:") && conn->allocptr.uagent) {
387     Curl_safefree(conn->allocptr.uagent);
388     conn->allocptr.uagent = NULL;
389   }
390   else if(!Curl_checkheaders(conn, "User-Agent:") &&
391           data->set.str[STRING_USERAGENT]) {
392     p_uagent = conn->allocptr.uagent;
393   }
394 
395   /* Referrer */
396   Curl_safefree(conn->allocptr.ref);
397   if(data->change.referer && !Curl_checkheaders(conn, "Referer:"))
398     conn->allocptr.ref = aprintf("Referer: %s\r\n", data->change.referer);
399   else
400     conn->allocptr.ref = NULL;
401 
402   p_referrer = conn->allocptr.ref;
403 
404   /*
405    * Range Header
406    * Only applies to PLAY, PAUSE, RECORD
407    *
408    * Go ahead and use the Range stuff supplied for HTTP
409    */
410   if(data->state.use_range &&
411      (rtspreq  & (RTSPREQ_PLAY | RTSPREQ_PAUSE | RTSPREQ_RECORD))) {
412 
413     /* Check to see if there is a range set in the custom headers */
414     if(!Curl_checkheaders(conn, "Range:") && data->state.range) {
415       Curl_safefree(conn->allocptr.rangeline);
416       conn->allocptr.rangeline = aprintf("Range: %s\r\n", data->state.range);
417       p_range = conn->allocptr.rangeline;
418     }
419   }
420 
421   /*
422    * Sanity check the custom headers
423    */
424   if(Curl_checkheaders(conn, "CSeq:")) {
425     failf(data, "CSeq cannot be set as a custom header.");
426     return CURLE_RTSP_CSEQ_ERROR;
427   }
428   if(Curl_checkheaders(conn, "Session:")) {
429     failf(data, "Session ID cannot be set as a custom header.");
430     return CURLE_BAD_FUNCTION_ARGUMENT;
431   }
432 
433   /* Initialize a dynamic send buffer */
434   req_buffer = Curl_add_buffer_init();
435 
436   if(!req_buffer)
437     return CURLE_OUT_OF_MEMORY;
438 
439   result =
440     Curl_add_bufferf(req_buffer,
441                      "%s %s RTSP/1.0\r\n" /* Request Stream-URI RTSP/1.0 */
442                      "CSeq: %ld\r\n", /* CSeq */
443                      (p_request ? p_request : ""), p_stream_uri,
444                      rtsp->CSeq_sent);
445   if(result)
446     return result;
447 
448   /*
449    * Rather than do a normal alloc line, keep the session_id unformatted
450    * to make comparison easier
451    */
452   if(p_session_id) {
453     result = Curl_add_bufferf(req_buffer, "Session: %s\r\n", p_session_id);
454     if(result)
455       return result;
456   }
457 
458   /*
459    * Shared HTTP-like options
460    */
461   result = Curl_add_bufferf(req_buffer,
462                             "%s" /* transport */
463                             "%s" /* accept */
464                             "%s" /* accept-encoding */
465                             "%s" /* range */
466                             "%s" /* referrer */
467                             "%s" /* user-agent */
468                             ,
469                             p_transport ? p_transport : "",
470                             p_accept ? p_accept : "",
471                             p_accept_encoding ? p_accept_encoding : "",
472                             p_range ? p_range : "",
473                             p_referrer ? p_referrer : "",
474                             p_uagent ? p_uagent : "");
475   if(result)
476     return result;
477 
478   if((rtspreq == RTSPREQ_SETUP) || (rtspreq == RTSPREQ_DESCRIBE)) {
479     result = Curl_add_timecondition(data, req_buffer);
480     if(result)
481       return result;
482   }
483 
484   result = Curl_add_custom_headers(conn, FALSE, req_buffer);
485   if(result)
486     return result;
487 
488   if(rtspreq == RTSPREQ_ANNOUNCE ||
489      rtspreq == RTSPREQ_SET_PARAMETER ||
490      rtspreq == RTSPREQ_GET_PARAMETER) {
491 
492     if(data->set.upload) {
493       putsize = data->state.infilesize;
494       data->set.httpreq = HTTPREQ_PUT;
495 
496     }
497     else {
498       postsize = (data->state.infilesize != -1)?
499         data->state.infilesize:
500         (data->set.postfields? (curl_off_t)strlen(data->set.postfields):0);
501       data->set.httpreq = HTTPREQ_POST;
502     }
503 
504     if(putsize > 0 || postsize > 0) {
505       /* As stated in the http comments, it is probably not wise to
506        * actually set a custom Content-Length in the headers */
507       if(!Curl_checkheaders(conn, "Content-Length:")) {
508         result = Curl_add_bufferf(req_buffer,
509             "Content-Length: %" CURL_FORMAT_CURL_OFF_T"\r\n",
510             (data->set.upload ? putsize : postsize));
511         if(result)
512           return result;
513       }
514 
515       if(rtspreq == RTSPREQ_SET_PARAMETER ||
516          rtspreq == RTSPREQ_GET_PARAMETER) {
517         if(!Curl_checkheaders(conn, "Content-Type:")) {
518           result = Curl_add_bufferf(req_buffer,
519               "Content-Type: text/parameters\r\n");
520           if(result)
521             return result;
522         }
523       }
524 
525       if(rtspreq == RTSPREQ_ANNOUNCE) {
526         if(!Curl_checkheaders(conn, "Content-Type:")) {
527           result = Curl_add_bufferf(req_buffer,
528               "Content-Type: application/sdp\r\n");
529           if(result)
530             return result;
531         }
532       }
533 
534       data->state.expect100header = FALSE; /* RTSP posts are simple/small */
535     }
536     else if(rtspreq == RTSPREQ_GET_PARAMETER) {
537       /* Check for an empty GET_PARAMETER (heartbeat) request */
538       data->set.httpreq = HTTPREQ_HEAD;
539       data->set.opt_no_body = TRUE;
540     }
541   }
542 
543   /* RTSP never allows chunked transfer */
544   data->req.forbidchunk = TRUE;
545   /* Finish the request buffer */
546   result = Curl_add_buffer(req_buffer, "\r\n", 2);
547   if(result)
548     return result;
549 
550   if(postsize > 0) {
551     result = Curl_add_buffer(req_buffer, data->set.postfields,
552                              (size_t)postsize);
553     if(result)
554       return result;
555   }
556 
557   /* issue the request */
558   result = Curl_add_buffer_send(req_buffer, conn,
559                                 &data->info.request_size, 0, FIRSTSOCKET);
560   if(result) {
561     failf(data, "Failed sending RTSP request");
562     return result;
563   }
564 
565   Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE, &http->readbytecount,
566                       putsize?FIRSTSOCKET:-1,
567                       putsize?&http->writebytecount:NULL);
568 
569   /* Increment the CSeq on success */
570   data->state.rtsp_next_client_CSeq++;
571 
572   if(http->writebytecount) {
573     /* if a request-body has been sent off, we make sure this progress is
574        noted properly */
575     Curl_pgrsSetUploadCounter(data, http->writebytecount);
576     if(Curl_pgrsUpdate(conn))
577       result = CURLE_ABORTED_BY_CALLBACK;
578   }
579 
580   return result;
581 }
582 
583 
rtsp_rtp_readwrite(struct SessionHandle * data,struct connectdata * conn,ssize_t * nread,bool * readmore)584 static CURLcode rtsp_rtp_readwrite(struct SessionHandle *data,
585                                    struct connectdata *conn,
586                                    ssize_t *nread,
587                                    bool *readmore) {
588   struct SingleRequest *k = &data->req;
589   struct rtsp_conn *rtspc = &(conn->proto.rtspc);
590 
591   char *rtp; /* moving pointer to rtp data */
592   ssize_t rtp_dataleft; /* how much data left to parse in this round */
593   char *scratch;
594   CURLcode result;
595 
596   if(rtspc->rtp_buf) {
597     /* There was some leftover data the last time. Merge buffers */
598     char *newptr = realloc(rtspc->rtp_buf, rtspc->rtp_bufsize + *nread);
599     if(!newptr) {
600       Curl_safefree(rtspc->rtp_buf);
601       rtspc->rtp_buf = NULL;
602       rtspc->rtp_bufsize = 0;
603       return CURLE_OUT_OF_MEMORY;
604     }
605     rtspc->rtp_buf = newptr;
606     memcpy(rtspc->rtp_buf + rtspc->rtp_bufsize, k->str, *nread);
607     rtspc->rtp_bufsize += *nread;
608     rtp = rtspc->rtp_buf;
609     rtp_dataleft = rtspc->rtp_bufsize;
610   }
611   else {
612     /* Just parse the request buffer directly */
613     rtp = k->str;
614     rtp_dataleft = *nread;
615   }
616 
617   while((rtp_dataleft > 0) &&
618         (rtp[0] == '$')) {
619     if(rtp_dataleft > 4) {
620       int rtp_length;
621 
622       /* Parse the header */
623       /* The channel identifier immediately follows and is 1 byte */
624       rtspc->rtp_channel = RTP_PKT_CHANNEL(rtp);
625 
626       /* The length is two bytes */
627       rtp_length = RTP_PKT_LENGTH(rtp);
628 
629       if(rtp_dataleft < rtp_length + 4) {
630         /* Need more - incomplete payload*/
631         *readmore = TRUE;
632         break;
633       }
634       else {
635         /* We have the full RTP interleaved packet
636          * Write out the header including the leading '$' */
637         DEBUGF(infof(data, "RTP write channel %d rtp_length %d\n",
638               rtspc->rtp_channel, rtp_length));
639         result = rtp_client_write(conn, &rtp[0], rtp_length + 4);
640         if(result) {
641           failf(data, "Got an error writing an RTP packet");
642           *readmore = FALSE;
643           Curl_safefree(rtspc->rtp_buf);
644           rtspc->rtp_buf = NULL;
645           rtspc->rtp_bufsize = 0;
646           return result;
647         }
648 
649         /* Move forward in the buffer */
650         rtp_dataleft -= rtp_length + 4;
651         rtp += rtp_length + 4;
652 
653         if(data->set.rtspreq == RTSPREQ_RECEIVE) {
654           /* If we are in a passive receive, give control back
655            * to the app as often as we can.
656            */
657           k->keepon &= ~KEEP_RECV;
658         }
659       }
660     }
661     else {
662       /* Need more - incomplete header */
663       *readmore = TRUE;
664       break;
665     }
666   }
667 
668   if(rtp_dataleft != 0 && rtp[0] == '$') {
669     DEBUGF(infof(data, "RTP Rewinding %zd %s\n", rtp_dataleft,
670           *readmore ? "(READMORE)" : ""));
671 
672     /* Store the incomplete RTP packet for a "rewind" */
673     scratch = malloc(rtp_dataleft);
674     if(!scratch) {
675       Curl_safefree(rtspc->rtp_buf);
676       rtspc->rtp_buf = NULL;
677       rtspc->rtp_bufsize = 0;
678       return CURLE_OUT_OF_MEMORY;
679     }
680     memcpy(scratch, rtp, rtp_dataleft);
681     Curl_safefree(rtspc->rtp_buf);
682     rtspc->rtp_buf = scratch;
683     rtspc->rtp_bufsize = rtp_dataleft;
684 
685     /* As far as the transfer is concerned, this data is consumed */
686     *nread = 0;
687     return CURLE_OK;
688   }
689   else {
690     /* Fix up k->str to point just after the last RTP packet */
691     k->str += *nread - rtp_dataleft;
692 
693     /* either all of the data has been read or...
694      * rtp now points at the next byte to parse
695      */
696     if(rtp_dataleft > 0)
697       DEBUGASSERT(k->str[0] == rtp[0]);
698 
699     DEBUGASSERT(rtp_dataleft <= *nread); /* sanity check */
700 
701     *nread = rtp_dataleft;
702   }
703 
704   /* If we get here, we have finished with the leftover/merge buffer */
705   Curl_safefree(rtspc->rtp_buf);
706   rtspc->rtp_buf = NULL;
707   rtspc->rtp_bufsize = 0;
708 
709   return CURLE_OK;
710 }
711 
712 static
rtp_client_write(struct connectdata * conn,char * ptr,size_t len)713 CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len)
714 {
715   struct SessionHandle *data = conn->data;
716   size_t wrote;
717   curl_write_callback writeit;
718 
719   if(len == 0) {
720     failf (data, "Cannot write a 0 size RTP packet.");
721     return CURLE_WRITE_ERROR;
722   }
723 
724   writeit = data->set.fwrite_rtp?data->set.fwrite_rtp:data->set.fwrite_func;
725   wrote = writeit(ptr, 1, len, data->set.rtp_out);
726 
727   if(CURL_WRITEFUNC_PAUSE == wrote) {
728     failf (data, "Cannot pause RTP");
729     return CURLE_WRITE_ERROR;
730   }
731 
732   if(wrote != len) {
733     failf (data, "Failed writing RTP data");
734     return CURLE_WRITE_ERROR;
735   }
736 
737   return CURLE_OK;
738 }
739 
Curl_rtsp_parseheader(struct connectdata * conn,char * header)740 CURLcode Curl_rtsp_parseheader(struct connectdata *conn,
741                                char *header)
742 {
743   struct SessionHandle *data = conn->data;
744   long CSeq = 0;
745 
746   if(checkprefix("CSeq:", header)) {
747     /* Store the received CSeq. Match is verified in rtsp_done */
748     int nc = sscanf(&header[4], ": %ld", &CSeq);
749     if(nc == 1) {
750       struct RTSP *rtsp = data->req.protop;
751       rtsp->CSeq_recv = CSeq; /* mark the request */
752       data->state.rtsp_CSeq_recv = CSeq; /* update the handle */
753     }
754     else {
755       failf(data, "Unable to read the CSeq header: [%s]", header);
756       return CURLE_RTSP_CSEQ_ERROR;
757     }
758   }
759   else if(checkprefix("Session:", header)) {
760     char *start;
761 
762     /* Find the first non-space letter */
763     start = header + 8;
764     while(*start && ISSPACE(*start))
765       start++;
766 
767     if(!*start) {
768       failf(data, "Got a blank Session ID");
769     }
770     else if(data->set.str[STRING_RTSP_SESSION_ID]) {
771       /* If the Session ID is set, then compare */
772       if(strncmp(start, data->set.str[STRING_RTSP_SESSION_ID],
773                  strlen(data->set.str[STRING_RTSP_SESSION_ID]))  != 0) {
774         failf(data, "Got RTSP Session ID Line [%s], but wanted ID [%s]",
775               start, data->set.str[STRING_RTSP_SESSION_ID]);
776         return CURLE_RTSP_SESSION_ERROR;
777       }
778     }
779     else {
780       /* If the Session ID is not set, and we find it in a response, then
781          set it */
782 
783       /* The session ID can be an alphanumeric or a 'safe' character
784        *
785        * RFC 2326 15.1 Base Syntax:
786        * safe =  "\$" | "-" | "_" | "." | "+"
787        * */
788       char *end = start;
789       while(*end &&
790             (ISALNUM(*end) || *end == '-' || *end == '_' || *end == '.' ||
791              *end == '+' ||
792              (*end == '\\' && *(end + 1) && *(end + 1) == '$' && (++end, 1))))
793         end++;
794 
795       /* Copy the id substring into a new buffer */
796       data->set.str[STRING_RTSP_SESSION_ID] = malloc(end - start + 1);
797       if(data->set.str[STRING_RTSP_SESSION_ID] == NULL)
798         return CURLE_OUT_OF_MEMORY;
799       memcpy(data->set.str[STRING_RTSP_SESSION_ID], start, end - start);
800       (data->set.str[STRING_RTSP_SESSION_ID])[end - start] = '\0';
801     }
802   }
803   return CURLE_OK;
804 }
805 
806 #endif /* CURL_DISABLE_RTSP */
807