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rtmphttp.c
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1 /*
2  * RTMP HTTP network protocol
3  * Copyright (c) 2012 Samuel Pitoiset
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * RTMP HTTP protocol
25  */
26 
27 #include "libavutil/avstring.h"
28 #include "libavutil/intfloat.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/time.h"
31 #include "internal.h"
32 #include "http.h"
33 #include "rtmp.h"
34 
35 #define RTMPT_DEFAULT_PORT 80
36 #define RTMPTS_DEFAULT_PORT RTMPS_DEFAULT_PORT
37 
38 /* protocol handler context */
39 typedef struct RTMP_HTTPContext {
40  const AVClass *class;
41  URLContext *stream; ///< HTTP stream
42  char host[256]; ///< hostname of the server
43  int port; ///< port to connect (default is 80)
44  char client_id[64]; ///< client ID used for all requests except the first one
45  int seq; ///< sequence ID used for all requests
46  uint8_t *out_data; ///< output buffer
47  int out_size; ///< current output buffer size
48  int out_capacity; ///< current output buffer capacity
49  int initialized; ///< flag indicating when the http context is initialized
50  int finishing; ///< flag indicating when the client closes the connection
51  int nb_bytes_read; ///< number of bytes read since the last request
52  int tls; ///< use Transport Security Layer (RTMPTS)
54 
55 static int rtmp_http_send_cmd(URLContext *h, const char *cmd)
56 {
57  RTMP_HTTPContext *rt = h->priv_data;
58  char uri[2048];
59  uint8_t c;
60  int ret;
61 
62  ff_url_join(uri, sizeof(uri), "http", NULL, rt->host, rt->port,
63  "/%s/%s/%d", cmd, rt->client_id, rt->seq++);
64 
65  av_opt_set_bin(rt->stream->priv_data, "post_data", rt->out_data,
66  rt->out_size, 0);
67 
68  /* send a new request to the server */
69  if ((ret = ff_http_do_new_request(rt->stream, uri)) < 0)
70  return ret;
71 
72  /* re-init output buffer */
73  rt->out_size = 0;
74 
75  /* read the first byte which contains the polling interval */
76  if ((ret = ffurl_read(rt->stream, &c, 1)) < 0)
77  return ret;
78 
79  /* re-init the number of bytes read */
80  rt->nb_bytes_read = 0;
81 
82  return ret;
83 }
84 
85 static int rtmp_http_write(URLContext *h, const uint8_t *buf, int size)
86 {
87  RTMP_HTTPContext *rt = h->priv_data;
88 
89  if (rt->out_size + size > rt->out_capacity) {
90  int err;
91  rt->out_capacity = (rt->out_size + size) * 2;
92  if ((err = av_reallocp(&rt->out_data, rt->out_capacity)) < 0) {
93  rt->out_size = 0;
94  rt->out_capacity = 0;
95  return err;
96  }
97  }
98 
99  memcpy(rt->out_data + rt->out_size, buf, size);
100  rt->out_size += size;
101 
102  return size;
103 }
104 
106 {
107  RTMP_HTTPContext *rt = h->priv_data;
108  int ret, off = 0;
109 
110  /* try to read at least 1 byte of data */
111  do {
112  ret = ffurl_read(rt->stream, buf + off, size);
113  if (ret < 0 && ret != AVERROR_EOF)
114  return ret;
115 
116  if (!ret || ret == AVERROR_EOF) {
117  if (rt->finishing) {
118  /* Do not send new requests when the client wants to
119  * close the connection. */
120  return AVERROR(EAGAIN);
121  }
122 
123  /* When the client has reached end of file for the last request,
124  * we have to send a new request if we have buffered data.
125  * Otherwise, we have to send an idle POST. */
126  if (rt->out_size > 0) {
127  if ((ret = rtmp_http_send_cmd(h, "send")) < 0)
128  return ret;
129  } else {
130  if (rt->nb_bytes_read == 0) {
131  /* Wait 50ms before retrying to read a server reply in
132  * order to reduce the number of idle requests. */
133  av_usleep(50000);
134  }
135 
136  if ((ret = rtmp_http_write(h, "", 1)) < 0)
137  return ret;
138 
139  if ((ret = rtmp_http_send_cmd(h, "idle")) < 0)
140  return ret;
141  }
142 
143  if (h->flags & AVIO_FLAG_NONBLOCK) {
144  /* no incoming data to handle in nonblocking mode */
145  return AVERROR(EAGAIN);
146  }
147  } else {
148  off += ret;
149  size -= ret;
150  rt->nb_bytes_read += ret;
151  }
152  } while (off <= 0);
153 
154  return off;
155 }
156 
158 {
159  RTMP_HTTPContext *rt = h->priv_data;
160  uint8_t tmp_buf[2048];
161  int ret = 0;
162 
163  if (rt->initialized) {
164  /* client wants to close the connection */
165  rt->finishing = 1;
166 
167  do {
168  ret = rtmp_http_read(h, tmp_buf, sizeof(tmp_buf));
169  } while (ret > 0);
170 
171  /* re-init output buffer before sending the close command */
172  rt->out_size = 0;
173 
174  if ((ret = rtmp_http_write(h, "", 1)) == 1)
175  ret = rtmp_http_send_cmd(h, "close");
176  }
177 
178  av_freep(&rt->out_data);
179  ffurl_close(rt->stream);
180 
181  return ret;
182 }
183 
184 static int rtmp_http_open(URLContext *h, const char *uri, int flags)
185 {
186  RTMP_HTTPContext *rt = h->priv_data;
187  char headers[1024], url[1024];
188  int ret, off = 0;
189 
190  av_url_split(NULL, 0, NULL, 0, rt->host, sizeof(rt->host), &rt->port,
191  NULL, 0, uri);
192 
193  /* This is the first request that is sent to the server in order to
194  * register a client on the server and start a new session. The server
195  * replies with a unique id (usually a number) that is used by the client
196  * for all future requests.
197  * Note: the reply doesn't contain a value for the polling interval.
198  * A successful connect resets the consecutive index that is used
199  * in the URLs. */
200  if (rt->tls) {
201  if (rt->port < 0)
203  ff_url_join(url, sizeof(url), "https", NULL, rt->host, rt->port, "/open/1");
204  } else {
205  if (rt->port < 0)
206  rt->port = RTMPT_DEFAULT_PORT;
207  ff_url_join(url, sizeof(url), "http", NULL, rt->host, rt->port, "/open/1");
208  }
209 
210  /* alloc the http context */
211  if ((ret = ffurl_alloc(&rt->stream, url, AVIO_FLAG_READ_WRITE, NULL)) < 0)
212  goto fail;
213 
214  /* set options */
215  snprintf(headers, sizeof(headers),
216  "Cache-Control: no-cache\r\n"
217  "Content-type: application/x-fcs\r\n"
218  "User-Agent: Shockwave Flash\r\n");
219  av_opt_set(rt->stream->priv_data, "headers", headers, 0);
220  av_opt_set(rt->stream->priv_data, "multiple_requests", "1", 0);
221  av_opt_set_bin(rt->stream->priv_data, "post_data", "", 1, 0);
222 
223  if (!rt->stream->protocol_whitelist && h->protocol_whitelist) {
225  if (!rt->stream->protocol_whitelist) {
226  ret = AVERROR(ENOMEM);
227  goto fail;
228  }
229  }
230 
231  /* open the http context */
232  if ((ret = ffurl_connect(rt->stream, NULL)) < 0)
233  goto fail;
234 
235  /* read the server reply which contains a unique ID */
236  for (;;) {
237  ret = ffurl_read(rt->stream, rt->client_id + off, sizeof(rt->client_id) - off);
238  if (!ret || ret == AVERROR_EOF)
239  break;
240  if (ret < 0)
241  goto fail;
242  off += ret;
243  if (off == sizeof(rt->client_id)) {
244  ret = AVERROR(EIO);
245  goto fail;
246  }
247  }
248  while (off > 0 && av_isspace(rt->client_id[off - 1]))
249  off--;
250  rt->client_id[off] = '\0';
251 
252  /* http context is now initialized */
253  rt->initialized = 1;
254  return 0;
255 
256 fail:
257  rtmp_http_close(h);
258  return ret;
259 }
260 
261 #define OFFSET(x) offsetof(RTMP_HTTPContext, x)
262 #define DEC AV_OPT_FLAG_DECODING_PARAM
263 
264 static const AVOption ffrtmphttp_options[] = {
265  {"ffrtmphttp_tls", "Use a HTTPS tunneling connection (RTMPTS).", OFFSET(tls), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC},
266  { NULL },
267 };
268 
269 static const AVClass ffrtmphttp_class = {
270  .class_name = "ffrtmphttp",
271  .item_name = av_default_item_name,
272  .option = ffrtmphttp_options,
273  .version = LIBAVUTIL_VERSION_INT,
274 };
275 
277  .name = "ffrtmphttp",
278  .url_open = rtmp_http_open,
279  .url_read = rtmp_http_read,
280  .url_write = rtmp_http_write,
281  .url_close = rtmp_http_close,
282  .priv_data_size = sizeof(RTMP_HTTPContext),
284  .priv_data_class= &ffrtmphttp_class,
285  .default_whitelist = "https,http,tcp,tls",
286 };
void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url)
Split a URL string into components.
Definition: utils.c:4429
#define NULL
Definition: coverity.c:32
int tls
use Transport Security Layer (RTMPTS)
Definition: rtmphttp.c:52
URLContext * stream
HTTP stream.
Definition: rtmphttp.c:41
#define URL_PROTOCOL_FLAG_NETWORK
Definition: url.h:34
const URLProtocol ff_ffrtmphttp_protocol
Definition: rtmphttp.c:276
AVOption.
Definition: opt.h:245
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
int ffurl_connect(URLContext *uc, AVDictionary **options)
Connect an URLContext that has been allocated by ffurl_alloc.
Definition: avio.c:166
int out_capacity
current output buffer capacity
Definition: rtmphttp.c:48
static av_const int av_isspace(int c)
Locale-independent conversion of ASCII isspace.
Definition: avstring.h:222
int av_opt_set_bin(void *obj, const char *name, const uint8_t *val, int len, int search_flags)
Definition: opt.c:554
int flags
Definition: url.h:43
uint8_t * out_data
output buffer
Definition: rtmphttp.c:46
#define OFFSET(x)
Definition: rtmphttp.c:261
int av_usleep(unsigned usec)
Sleep for a period of time.
Definition: time.c:76
#define RTMPTS_DEFAULT_PORT
Definition: rtmphttp.c:36
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
uint8_t
AVOptions.
int out_size
current output buffer size
Definition: rtmphttp.c:47
static const AVOption ffrtmphttp_options[]
Definition: rtmphttp.c:264
int nb_bytes_read
number of bytes read since the last request
Definition: rtmphttp.c:51
#define AVERROR_EOF
End of file.
Definition: error.h:55
ptrdiff_t size
Definition: opengl_enc.c:101
char client_id[64]
client ID used for all requests except the first one
Definition: rtmphttp.c:44
int ffurl_alloc(URLContext **puc, const char *filename, int flags, const AVIOInterruptCB *int_cb)
Create a URLContext for accessing to the resource indicated by url, but do not initiate the connectio...
Definition: avio.c:292
static int rtmp_http_send_cmd(URLContext *h, const char *cmd)
Definition: rtmphttp.c:55
const char * protocol_whitelist
Definition: url.h:49
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
int seq
sequence ID used for all requests
Definition: rtmphttp.c:45
#define fail()
Definition: checkasm.h:82
static int rtmp_http_open(URLContext *h, const char *uri, int flags)
Definition: rtmphttp.c:184
int ff_url_join(char *str, int size, const char *proto, const char *authorization, const char *hostname, int port, const char *fmt,...)
Definition: url.c:36
#define RTMPT_DEFAULT_PORT
Definition: rtmphttp.c:35
static int rtmp_http_close(URLContext *h)
Definition: rtmphttp.c:157
int av_reallocp(void *ptr, size_t size)
Allocate, reallocate, or free a block of memory through a pointer to a pointer.
Definition: mem.c:187
#define DEC
Definition: rtmphttp.c:262
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:267
#define AVIO_FLAG_NONBLOCK
Use non-blocking mode.
Definition: avio.h:625
void * buf
Definition: avisynth_c.h:690
Definition: url.h:38
#define AVIO_FLAG_READ_WRITE
read-write pseudo flag
Definition: avio.h:608
static int rtmp_http_write(URLContext *h, const uint8_t *buf, int size)
Definition: rtmphttp.c:85
Describe the class of an AVClass context structure.
Definition: log.h:67
void * priv_data
Definition: url.h:41
#define snprintf
Definition: snprintf.h:34
static const AVClass ffrtmphttp_class
Definition: rtmphttp.c:269
const char * name
Definition: url.h:54
int finishing
flag indicating when the client closes the connection
Definition: rtmphttp.c:50
static int flags
Definition: cpu.c:47
int ffurl_close(URLContext *h)
Definition: avio.c:467
int ff_http_do_new_request(URLContext *h, const char *uri)
Send a new HTTP request, reusing the old connection.
Definition: http.c:299
static int rtmp_http_read(URLContext *h, uint8_t *buf, int size)
Definition: rtmphttp.c:105
static double c[64]
int port
port to connect (default is 80)
Definition: rtmphttp.c:43
int initialized
flag indicating when the http context is initialized
Definition: rtmphttp.c:49
#define av_freep(p)
char host[256]
hostname of the server
Definition: rtmphttp.c:42
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:431
int ffurl_read(URLContext *h, unsigned char *buf, int size)
Read up to size bytes from the resource accessed by h, and store the read bytes in buf...
Definition: avio.c:407