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curl/lib/rtsp.c
Kamil Dudka 5c7c9a768d url: provide dead_connection flag in Curl_handler::disconnect
It helps to prevent a hangup with some FTP servers in case idle session
timeout has exceeded.  But it may be useful also for other protocols
that send any quit message on disconnect.  Currently used by FTP, POP3,
IMAP and SMTP.
2010-12-06 14:35:42 +01:00

754 lines
22 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2010, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at http://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
#include "setup.h"
#ifndef CURL_DISABLE_RTSP
#include "urldata.h"
#include <curl/curl.h>
#include "transfer.h"
#include "sendf.h"
#include "easyif.h" /* for Curl_convert_... prototypes */
#include "multiif.h"
#include "http.h"
#include "url.h"
#include "progress.h"
#include "rtsp.h"
#include "rawstr.h"
#include "curl_memory.h"
#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>
/* The last #include file should be: */
#include "memdebug.h"
/*
* TODO (general)
* -incoming server requests
* -server CSeq counter
* -digest authentication
* -connect thru proxy
* -pipelining?
*/
#define RTP_PKT_CHANNEL(p) ((int)((unsigned char)((p)[1])))
#define RTP_PKT_LENGTH(p) ((((int)((unsigned char)((p)[2]))) << 8) | \
((int)((unsigned char)((p)[3]))))
static int rtsp_getsock_do(struct connectdata *conn,
curl_socket_t *socks,
int numsocks);
/* this returns the socket to wait for in the DO and DOING state for the multi
interface and then we're always _sending_ a request and thus we wait for
the single socket to become writable only */
static int rtsp_getsock_do(struct connectdata *conn,
curl_socket_t *socks,
int numsocks)
{
/* write mode */
(void)numsocks; /* unused, we trust it to be at least 1 */
socks[0] = conn->sock[FIRSTSOCKET];
return GETSOCK_WRITESOCK(0);
}
static
CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len);
/*
* RTSP handler interface.
*/
const struct Curl_handler Curl_handler_rtsp = {
"RTSP", /* scheme */
ZERO_NULL, /* setup_connection */
Curl_rtsp, /* do_it */
Curl_rtsp_done, /* done */
ZERO_NULL, /* do_more */
Curl_rtsp_connect, /* connect_it */
ZERO_NULL, /* connecting */
ZERO_NULL, /* doing */
ZERO_NULL, /* proto_getsock */
rtsp_getsock_do, /* doing_getsock */
ZERO_NULL, /* perform_getsock */
Curl_rtsp_disconnect, /* disconnect */
PORT_RTSP, /* defport */
PROT_RTSP, /* protocol */
};
CURLcode Curl_rtsp_connect(struct connectdata *conn, bool *done)
{
CURLcode httpStatus;
struct SessionHandle *data = conn->data;
httpStatus = Curl_http_connect(conn, done);
/* Initialize the CSeq if not already done */
if(data->state.rtsp_next_client_CSeq == 0)
data->state.rtsp_next_client_CSeq = 1;
if(data->state.rtsp_next_server_CSeq == 0)
data->state.rtsp_next_server_CSeq = 1;
conn->proto.rtspc.rtp_channel = -1;
return httpStatus;
}
CURLcode Curl_rtsp_disconnect(struct connectdata *conn, bool dead_connection)
{
(void) dead_connection;
Curl_safefree(conn->proto.rtspc.rtp_buf);
return CURLE_OK;
}
CURLcode Curl_rtsp_done(struct connectdata *conn,
CURLcode status, bool premature)
{
struct SessionHandle *data = conn->data;
struct RTSP *rtsp = data->state.proto.rtsp;
CURLcode httpStatus;
long CSeq_sent;
long CSeq_recv;
/* Bypass HTTP empty-reply checks on receive */
if(data->set.rtspreq == RTSPREQ_RECEIVE)
premature = TRUE;
httpStatus = Curl_http_done(conn, status, premature);
if(rtsp) {
/* Check the sequence numbers */
CSeq_sent = rtsp->CSeq_sent;
CSeq_recv = rtsp->CSeq_recv;
if((data->set.rtspreq != RTSPREQ_RECEIVE) && (CSeq_sent != CSeq_recv)) {
failf(data, "The CSeq of this request %ld did not match the response %ld",
CSeq_sent, CSeq_recv);
return CURLE_RTSP_CSEQ_ERROR;
}
else if(data->set.rtspreq == RTSPREQ_RECEIVE &&
(conn->proto.rtspc.rtp_channel == -1)) {
infof(data, "Got an RTP Receive with a CSeq of %ld\n", CSeq_recv);
/* TODO CPC: Server -> Client logic here */
}
}
return httpStatus;
}
CURLcode Curl_rtsp(struct connectdata *conn, bool *done)
{
struct SessionHandle *data = conn->data;
CURLcode result=CURLE_OK;
Curl_RtspReq rtspreq = data->set.rtspreq;
struct RTSP *rtsp;
struct HTTP *http;
Curl_send_buffer *req_buffer;
curl_off_t postsize = 0; /* for ANNOUNCE and SET_PARAMETER */
curl_off_t putsize = 0; /* for ANNOUNCE and SET_PARAMETER */
const char *p_request = NULL;
const char *p_session_id = NULL;
const char *p_accept = NULL;
const char *p_accept_encoding = NULL;
const char *p_range = NULL;
const char *p_referrer = NULL;
const char *p_stream_uri = NULL;
const char *p_transport = NULL;
const char *p_uagent = NULL;
*done = TRUE;
Curl_reset_reqproto(conn);
if(!data->state.proto.rtsp) {
/* Only allocate this struct if we don't already have it! */
rtsp = calloc(1, sizeof(struct RTSP));
if(!rtsp)
return CURLE_OUT_OF_MEMORY;
data->state.proto.rtsp = rtsp;
}
else {
rtsp = data->state.proto.rtsp;
}
http = &(rtsp->http_wrapper);
/* Assert that no one has changed the RTSP struct in an evil way */
DEBUGASSERT((void *)http == (void *)rtsp);
rtsp->CSeq_sent = data->state.rtsp_next_client_CSeq;
rtsp->CSeq_recv = 0;
/* Setup the 'p_request' pointer to the proper p_request string
* Since all RTSP requests are included here, there is no need to
* support custom requests like HTTP.
**/
DEBUGASSERT((rtspreq > RTSPREQ_NONE && rtspreq < RTSPREQ_LAST));
data->set.opt_no_body = TRUE; /* most requests don't contain a body */
switch(rtspreq) {
case RTSPREQ_NONE:
failf(data, "Got invalid RTSP request: RTSPREQ_NONE");
return CURLE_BAD_FUNCTION_ARGUMENT;
case RTSPREQ_OPTIONS:
p_request = "OPTIONS";
break;
case RTSPREQ_DESCRIBE:
p_request = "DESCRIBE";
data->set.opt_no_body = FALSE;
break;
case RTSPREQ_ANNOUNCE:
p_request = "ANNOUNCE";
break;
case RTSPREQ_SETUP:
p_request = "SETUP";
break;
case RTSPREQ_PLAY:
p_request = "PLAY";
break;
case RTSPREQ_PAUSE:
p_request = "PAUSE";
break;
case RTSPREQ_TEARDOWN:
p_request = "TEARDOWN";
break;
case RTSPREQ_GET_PARAMETER:
/* GET_PARAMETER's no_body status is determined later */
p_request = "GET_PARAMETER";
break;
case RTSPREQ_SET_PARAMETER:
p_request = "SET_PARAMETER";
break;
case RTSPREQ_RECORD:
p_request = "RECORD";
break;
case RTSPREQ_RECEIVE:
p_request = "";
/* Treat interleaved RTP as body*/
data->set.opt_no_body = FALSE;
break;
case RTSPREQ_LAST:
failf(data, "Got invalid RTSP request: RTSPREQ_LAST");
return CURLE_BAD_FUNCTION_ARGUMENT;
}
if(rtspreq == RTSPREQ_RECEIVE) {
Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE,
&http->readbytecount, -1, NULL);
return result;
}
p_session_id = data->set.str[STRING_RTSP_SESSION_ID];
if(!p_session_id &&
(rtspreq & ~(RTSPREQ_OPTIONS | RTSPREQ_DESCRIBE | RTSPREQ_SETUP))) {
failf(data, "Refusing to issue an RTSP request [%s] without a session ID.",
p_request ? p_request : "");
return CURLE_BAD_FUNCTION_ARGUMENT;
}
/* TODO: auth? */
/* TODO: proxy? */
/* Stream URI. Default to server '*' if not specified */
if(data->set.str[STRING_RTSP_STREAM_URI]) {
p_stream_uri = data->set.str[STRING_RTSP_STREAM_URI];
}
else {
p_stream_uri = "*";
}
/* Transport Header for SETUP requests */
p_transport = Curl_checkheaders(data, "Transport:");
if(rtspreq == RTSPREQ_SETUP && !p_transport) {
/* New Transport: setting? */
if(data->set.str[STRING_RTSP_TRANSPORT]) {
Curl_safefree(conn->allocptr.rtsp_transport);
conn->allocptr.rtsp_transport =
aprintf("Transport: %s\r\n",
data->set.str[STRING_RTSP_TRANSPORT]);
if(!conn->allocptr.rtsp_transport)
return CURLE_OUT_OF_MEMORY;
}
else {
failf(data,
"Refusing to issue an RTSP SETUP without a Transport: header.");
return CURLE_BAD_FUNCTION_ARGUMENT;
}
p_transport = conn->allocptr.rtsp_transport;
}
/* Accept Headers for DESCRIBE requests */
if(rtspreq == RTSPREQ_DESCRIBE) {
/* Accept Header */
p_accept = Curl_checkheaders(data, "Accept:")?
NULL:"Accept: application/sdp\r\n";
/* Accept-Encoding header */
if(!Curl_checkheaders(data, "Accept-Encoding:") &&
data->set.str[STRING_ENCODING]) {
Curl_safefree(conn->allocptr.accept_encoding);
conn->allocptr.accept_encoding =
aprintf("Accept-Encoding: %s\r\n", data->set.str[STRING_ENCODING]);
if(!conn->allocptr.accept_encoding)
return CURLE_OUT_OF_MEMORY;
p_accept_encoding = conn->allocptr.accept_encoding;
}
}
/* The User-Agent string might have been allocated in url.c already, because
it might have been used in the proxy connect, but if we have got a header
with the user-agent string specified, we erase the previously made string
here. */
if(Curl_checkheaders(data, "User-Agent:") && conn->allocptr.uagent) {
Curl_safefree(conn->allocptr.uagent);
conn->allocptr.uagent = NULL;
}
else if(!Curl_checkheaders(data, "User-Agent:") &&
data->set.str[STRING_USERAGENT]) {
p_uagent = conn->allocptr.uagent;
}
/* Referrer */
Curl_safefree(conn->allocptr.ref);
if(data->change.referer && !Curl_checkheaders(data, "Referer:"))
conn->allocptr.ref = aprintf("Referer: %s\r\n", data->change.referer);
else
conn->allocptr.ref = NULL;
p_referrer = conn->allocptr.ref;
/*
* Range Header
* Only applies to PLAY, PAUSE, RECORD
*
* Go ahead and use the Range stuff supplied for HTTP
*/
if(data->state.use_range &&
(rtspreq & (RTSPREQ_PLAY | RTSPREQ_PAUSE | RTSPREQ_RECORD))) {
/* Check to see if there is a range set in the custom headers */
if(!Curl_checkheaders(data, "Range:") && data->state.range) {
Curl_safefree(conn->allocptr.rangeline);
conn->allocptr.rangeline = aprintf("Range: %s\r\n", data->state.range);
p_range = conn->allocptr.rangeline;
}
}
/*
* Sanity check the custom headers
*/
if(Curl_checkheaders(data, "CSeq:")) {
failf(data, "CSeq cannot be set as a custom header.");
return CURLE_RTSP_CSEQ_ERROR;
}
if(Curl_checkheaders(data, "Session:")) {
failf(data, "Session ID cannot be set as a custom header.");
return CURLE_BAD_FUNCTION_ARGUMENT;
}
/* Initialize a dynamic send buffer */
req_buffer = Curl_add_buffer_init();
if(!req_buffer)
return CURLE_OUT_OF_MEMORY;
result =
Curl_add_bufferf(req_buffer,
"%s %s RTSP/1.0\r\n" /* Request Stream-URI RTSP/1.0 */
"CSeq: %ld\r\n", /* CSeq */
(p_request ? p_request : ""), p_stream_uri,
rtsp->CSeq_sent);
if(result)
return result;
/*
* Rather than do a normal alloc line, keep the session_id unformatted
* to make comparison easier
*/
if(p_session_id) {
result = Curl_add_bufferf(req_buffer, "Session: %s\r\n", p_session_id);
if(result)
return result;
}
/*
* Shared HTTP-like options
*/
result = Curl_add_bufferf(req_buffer,
"%s" /* transport */
"%s" /* accept */
"%s" /* accept-encoding */
"%s" /* range */
"%s" /* referrer */
"%s" /* user-agent */
,
p_transport ? p_transport : "",
p_accept ? p_accept : "",
p_accept_encoding ? p_accept_encoding : "",
p_range ? p_range : "",
p_referrer ? p_referrer : "",
p_uagent ? p_uagent : "");
if(result)
return result;
if((rtspreq == RTSPREQ_SETUP) || (rtspreq == RTSPREQ_DESCRIBE)) {
result = Curl_add_timecondition(data, req_buffer);
if(result)
return result;
}
result = Curl_add_custom_headers(conn, req_buffer);
if(result)
return result;
if(rtspreq == RTSPREQ_ANNOUNCE ||
rtspreq == RTSPREQ_SET_PARAMETER ||
rtspreq == RTSPREQ_GET_PARAMETER) {
if(data->set.upload) {
putsize = data->set.infilesize;
data->set.httpreq = HTTPREQ_PUT;
}
else {
postsize = (data->set.postfieldsize != -1)?
data->set.postfieldsize:
(data->set.postfields? (curl_off_t)strlen(data->set.postfields):0);
data->set.httpreq = HTTPREQ_POST;
}
if(putsize > 0 || postsize > 0) {
/* As stated in the http comments, it is probably not wise to
* actually set a custom Content-Length in the headers */
if(!Curl_checkheaders(data, "Content-Length:")) {
result = Curl_add_bufferf(req_buffer,
"Content-Length: %" FORMAT_OFF_T"\r\n",
(data->set.upload ? putsize : postsize));
if(result)
return result;
}
if(rtspreq == RTSPREQ_SET_PARAMETER ||
rtspreq == RTSPREQ_GET_PARAMETER) {
if(!Curl_checkheaders(data, "Content-Type:")) {
result = Curl_add_bufferf(req_buffer,
"Content-Type: text/parameters\r\n");
if(result)
return result;
}
}
if(rtspreq == RTSPREQ_ANNOUNCE) {
if(!Curl_checkheaders(data, "Content-Type:")) {
result = Curl_add_bufferf(req_buffer,
"Content-Type: application/sdp\r\n");
if(result)
return result;
}
}
data->state.expect100header = FALSE; /* RTSP posts are simple/small */
} else if(rtspreq == RTSPREQ_GET_PARAMETER) {
/* Check for an empty GET_PARAMETER (heartbeat) request */
data->set.httpreq = HTTPREQ_HEAD;
data->set.opt_no_body = TRUE;
}
}
/* RTSP never allows chunked transfer */
data->req.forbidchunk = TRUE;
/* Finish the request buffer */
result = Curl_add_buffer(req_buffer, "\r\n", 2);
if(result)
return result;
if(postsize > 0) {
result = Curl_add_buffer(req_buffer, data->set.postfields,
(size_t)postsize);
if(result)
return result;
}
/* issue the request */
result = Curl_add_buffer_send(req_buffer, conn,
&data->info.request_size, 0, FIRSTSOCKET);
if(result) {
failf(data, "Failed sending RTSP request");
return result;
}
Curl_setup_transfer(conn, FIRSTSOCKET, -1, TRUE, &http->readbytecount,
putsize?FIRSTSOCKET:-1,
putsize?&http->writebytecount:NULL);
/* Increment the CSeq on success */
data->state.rtsp_next_client_CSeq++;
if(http->writebytecount) {
/* if a request-body has been sent off, we make sure this progress is
noted properly */
Curl_pgrsSetUploadCounter(data, http->writebytecount);
if(Curl_pgrsUpdate(conn))
result = CURLE_ABORTED_BY_CALLBACK;
}
return result;
}
CURLcode Curl_rtsp_rtp_readwrite(struct SessionHandle *data,
struct connectdata *conn,
ssize_t *nread,
bool *readmore) {
struct SingleRequest *k = &data->req;
struct rtsp_conn *rtspc = &(conn->proto.rtspc);
char *rtp; /* moving pointer to rtp data */
ssize_t rtp_dataleft; /* how much data left to parse in this round */
char *scratch;
CURLcode result;
if(rtspc->rtp_buf) {
/* There was some leftover data the last time. Merge buffers */
char *newptr = realloc(rtspc->rtp_buf, rtspc->rtp_bufsize + *nread);
if(!newptr) {
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OUT_OF_MEMORY;
}
rtspc->rtp_buf = newptr;
memcpy(rtspc->rtp_buf + rtspc->rtp_bufsize, k->str, *nread);
rtspc->rtp_bufsize += *nread;
rtp = rtspc->rtp_buf;
rtp_dataleft = rtspc->rtp_bufsize;
}
else {
/* Just parse the request buffer directly */
rtp = k->str;
rtp_dataleft = *nread;
}
while((rtp_dataleft > 0) &&
(rtp[0] == '$')) {
if(rtp_dataleft > 4) {
int rtp_length;
/* Parse the header */
/* The channel identifier immediately follows and is 1 byte */
rtspc->rtp_channel = RTP_PKT_CHANNEL(rtp);
/* The length is two bytes */
rtp_length = RTP_PKT_LENGTH(rtp);
if(rtp_dataleft < rtp_length + 4) {
/* Need more - incomplete payload*/
*readmore = TRUE;
break;
}
else {
/* We have the full RTP interleaved packet
* Write out the header including the leading '$' */
DEBUGF(infof(data, "RTP write channel %d rtp_length %d\n",
rtspc->rtp_channel, rtp_length));
result = rtp_client_write(conn, &rtp[0], rtp_length + 4);
if(result) {
failf(data, "Got an error writing an RTP packet");
*readmore = FALSE;
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return result;
}
/* Move forward in the buffer */
rtp_dataleft -= rtp_length + 4;
rtp += rtp_length + 4;
if(data->set.rtspreq == RTSPREQ_RECEIVE) {
/* If we are in a passive receive, give control back
* to the app as often as we can.
*/
k->keepon &= ~KEEP_RECV;
}
}
}
else {
/* Need more - incomplete header */
*readmore = TRUE;
break;
}
}
if(rtp_dataleft != 0 && rtp[0] == '$') {
DEBUGF(infof(data, "RTP Rewinding %zu %s\n", rtp_dataleft,
*readmore ? "(READMORE)" : ""));
/* Store the incomplete RTP packet for a "rewind" */
scratch = malloc(rtp_dataleft);
if(!scratch) {
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OUT_OF_MEMORY;
}
memcpy(scratch, rtp, rtp_dataleft);
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = scratch;
rtspc->rtp_bufsize = rtp_dataleft;
/* As far as the transfer is concerned, this data is consumed */
*nread = 0;
return CURLE_OK;
}
else {
/* Fix up k->str to point just after the last RTP packet */
k->str += *nread - rtp_dataleft;
/* either all of the data has been read or...
* rtp now points at the next byte to parse
*/
if(rtp_dataleft > 0)
DEBUGASSERT(k->str[0] == rtp[0]);
DEBUGASSERT(rtp_dataleft <= *nread); /* sanity check */
*nread = rtp_dataleft;
}
/* If we get here, we have finished with the leftover/merge buffer */
Curl_safefree(rtspc->rtp_buf);
rtspc->rtp_buf = NULL;
rtspc->rtp_bufsize = 0;
return CURLE_OK;
}
static
CURLcode rtp_client_write(struct connectdata *conn, char *ptr, size_t len)
{
struct SessionHandle *data = conn->data;
size_t wrote;
curl_write_callback writeit;
if(len == 0) {
failf (data, "Cannot write a 0 size RTP packet.");
return CURLE_WRITE_ERROR;
}
writeit = data->set.fwrite_rtp?data->set.fwrite_rtp:data->set.fwrite_func;
wrote = writeit(ptr, 1, len, data->set.rtp_out);
if(CURL_WRITEFUNC_PAUSE == wrote) {
failf (data, "Cannot pause RTP");
return CURLE_WRITE_ERROR;
}
if(wrote != len) {
failf (data, "Failed writing RTP data");
return CURLE_WRITE_ERROR;
}
return CURLE_OK;
}
CURLcode Curl_rtsp_parseheader(struct connectdata *conn,
char *header)
{
struct SessionHandle *data = conn->data;
long CSeq = 0;
if(checkprefix("CSeq:", header)) {
/* Store the received CSeq. Match is verified in rtsp_done */
int nc;
char *temp = strdup(header);
if(!temp)
return CURLE_OUT_OF_MEMORY;
Curl_strntoupper(temp, temp, sizeof(temp));
nc = sscanf(temp, "CSEQ: %ld", &CSeq);
free(temp);
if(nc == 1) {
data->state.proto.rtsp->CSeq_recv = CSeq; /* mark the request */
data->state.rtsp_CSeq_recv = CSeq; /* update the handle */
}
else {
failf(data, "Unable to read the CSeq header: [%s]", header);
return CURLE_RTSP_CSEQ_ERROR;
}
}
else if(checkprefix("Session:", header)) {
char *start;
/* Find the first non-space letter */
start = header + 9;
while(*start && ISSPACE(*start))
start++;
if(!*start) {
failf(data, "Got a blank Session ID");
}
else if(data->set.str[STRING_RTSP_SESSION_ID]) {
/* If the Session ID is set, then compare */
if(strncmp(start, data->set.str[STRING_RTSP_SESSION_ID],
strlen(data->set.str[STRING_RTSP_SESSION_ID])) != 0) {
failf(data, "Got RTSP Session ID Line [%s], but wanted ID [%s]",
start, data->set.str[STRING_RTSP_SESSION_ID]);
return CURLE_RTSP_SESSION_ERROR;
}
}
else {
/* If the Session ID is not set, and we find it in a response, then
set it */
/* The session ID can be an alphanumeric or a 'safe' character
*
* RFC 2326 15.1 Base Syntax:
* safe = "\$" | "-" | "_" | "." | "+"
* */
char *end = start;
while(*end &&
(ISALNUM(*end) || *end == '-' || *end == '_' || *end == '.' ||
*end == '+' ||
(*end == '\\' && *(end + 1) && *(end + 1) == '$' && (++end, 1))))
end++;
/* Copy the id substring into a new buffer */
data->set.str[STRING_RTSP_SESSION_ID] = malloc(end - start + 1);
if(data->set.str[STRING_RTSP_SESSION_ID] == NULL)
return CURLE_OUT_OF_MEMORY;
memcpy(data->set.str[STRING_RTSP_SESSION_ID], start, end - start);
(data->set.str[STRING_RTSP_SESSION_ID])[end - start] = '\0';
}
}
return CURLE_OK;
}
#endif /* CURL_DISABLE_RTSP */