yading@11: /*
yading@11:  * RTMP HTTP network protocol
yading@11:  * Copyright (c) 2012 Samuel Pitoiset
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * RTMP HTTP protocol
yading@11:  */
yading@11: 
yading@11: #include "libavutil/avstring.h"
yading@11: #include "libavutil/intfloat.h"
yading@11: #include "libavutil/opt.h"
yading@11: #include "libavutil/time.h"
yading@11: #include "internal.h"
yading@11: #include "http.h"
yading@11: #include "rtmp.h"
yading@11: 
yading@11: #define RTMPT_DEFAULT_PORT 80
yading@11: #define RTMPTS_DEFAULT_PORT RTMPS_DEFAULT_PORT
yading@11: 
yading@11: /* protocol handler context */
yading@11: typedef struct RTMP_HTTPContext {
yading@11:     const AVClass *class;
yading@11:     URLContext   *stream;           ///< HTTP stream
yading@11:     char         host[256];         ///< hostname of the server
yading@11:     int          port;              ///< port to connect (default is 80)
yading@11:     char         client_id[64];     ///< client ID used for all requests except the first one
yading@11:     int          seq;               ///< sequence ID used for all requests
yading@11:     uint8_t      *out_data;         ///< output buffer
yading@11:     int          out_size;          ///< current output buffer size
yading@11:     int          out_capacity;      ///< current output buffer capacity
yading@11:     int          initialized;       ///< flag indicating when the http context is initialized
yading@11:     int          finishing;         ///< flag indicating when the client closes the connection
yading@11:     int          nb_bytes_read;     ///< number of bytes read since the last request
yading@11:     int          tls;               ///< use Transport Security Layer (RTMPTS)
yading@11: } RTMP_HTTPContext;
yading@11: 
yading@11: static int rtmp_http_send_cmd(URLContext *h, const char *cmd)
yading@11: {
yading@11:     RTMP_HTTPContext *rt = h->priv_data;
yading@11:     char uri[2048];
yading@11:     uint8_t c;
yading@11:     int ret;
yading@11: 
yading@11:     ff_url_join(uri, sizeof(uri), "http", NULL, rt->host, rt->port,
yading@11:                 "/%s/%s/%d", cmd, rt->client_id, rt->seq++);
yading@11: 
yading@11:     av_opt_set_bin(rt->stream->priv_data, "post_data", rt->out_data,
yading@11:                    rt->out_size, 0);
yading@11: 
yading@11:     /* send a new request to the server */
yading@11:     if ((ret = ff_http_do_new_request(rt->stream, uri)) < 0)
yading@11:         return ret;
yading@11: 
yading@11:     /* re-init output buffer */
yading@11:     rt->out_size = 0;
yading@11: 
yading@11:     /* read the first byte which contains the polling interval */
yading@11:     if ((ret = ffurl_read(rt->stream, &c, 1)) < 0)
yading@11:         return ret;
yading@11: 
yading@11:     /* re-init the number of bytes read */
yading@11:     rt->nb_bytes_read = 0;
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int rtmp_http_write(URLContext *h, const uint8_t *buf, int size)
yading@11: {
yading@11:     RTMP_HTTPContext *rt = h->priv_data;
yading@11:     void *ptr;
yading@11: 
yading@11:     if (rt->out_size + size > rt->out_capacity) {
yading@11:         rt->out_capacity = (rt->out_size + size) * 2;
yading@11:         ptr = av_realloc(rt->out_data, rt->out_capacity);
yading@11:         if (!ptr)
yading@11:             return AVERROR(ENOMEM);
yading@11:         rt->out_data = ptr;
yading@11:     }
yading@11: 
yading@11:     memcpy(rt->out_data + rt->out_size, buf, size);
yading@11:     rt->out_size += size;
yading@11: 
yading@11:     return size;
yading@11: }
yading@11: 
yading@11: static int rtmp_http_read(URLContext *h, uint8_t *buf, int size)
yading@11: {
yading@11:     RTMP_HTTPContext *rt = h->priv_data;
yading@11:     int ret, off = 0;
yading@11: 
yading@11:     /* try to read at least 1 byte of data */
yading@11:     do {
yading@11:         ret = ffurl_read(rt->stream, buf + off, size);
yading@11:         if (ret < 0 && ret != AVERROR_EOF)
yading@11:             return ret;
yading@11: 
yading@11:         if (ret == AVERROR_EOF) {
yading@11:             if (rt->finishing) {
yading@11:                 /* Do not send new requests when the client wants to
yading@11:                  * close the connection. */
yading@11:                 return AVERROR(EAGAIN);
yading@11:             }
yading@11: 
yading@11:             /* When the client has reached end of file for the last request,
yading@11:              * we have to send a new request if we have buffered data.
yading@11:              * Otherwise, we have to send an idle POST. */
yading@11:             if (rt->out_size > 0) {
yading@11:                 if ((ret = rtmp_http_send_cmd(h, "send")) < 0)
yading@11:                     return ret;
yading@11:             } else {
yading@11:                 if (rt->nb_bytes_read == 0) {
yading@11:                     /* Wait 50ms before retrying to read a server reply in
yading@11:                      * order to reduce the number of idle requets. */
yading@11:                     av_usleep(50000);
yading@11:                 }
yading@11: 
yading@11:                 if ((ret = rtmp_http_write(h, "", 1)) < 0)
yading@11:                     return ret;
yading@11: 
yading@11:                 if ((ret = rtmp_http_send_cmd(h, "idle")) < 0)
yading@11:                     return ret;
yading@11:             }
yading@11: 
yading@11:             if (h->flags & AVIO_FLAG_NONBLOCK) {
yading@11:                 /* no incoming data to handle in nonblocking mode */
yading@11:                 return AVERROR(EAGAIN);
yading@11:             }
yading@11:         } else {
yading@11:             off  += ret;
yading@11:             size -= ret;
yading@11:             rt->nb_bytes_read += ret;
yading@11:         }
yading@11:     } while (off <= 0);
yading@11: 
yading@11:     return off;
yading@11: }
yading@11: 
yading@11: static int rtmp_http_close(URLContext *h)
yading@11: {
yading@11:     RTMP_HTTPContext *rt = h->priv_data;
yading@11:     uint8_t tmp_buf[2048];
yading@11:     int ret = 0;
yading@11: 
yading@11:     if (rt->initialized) {
yading@11:         /* client wants to close the connection */
yading@11:         rt->finishing = 1;
yading@11: 
yading@11:         do {
yading@11:             ret = rtmp_http_read(h, tmp_buf, sizeof(tmp_buf));
yading@11:         } while (ret > 0);
yading@11: 
yading@11:         /* re-init output buffer before sending the close command */
yading@11:         rt->out_size = 0;
yading@11: 
yading@11:         if ((ret = rtmp_http_write(h, "", 1)) == 1)
yading@11:             ret = rtmp_http_send_cmd(h, "close");
yading@11:     }
yading@11: 
yading@11:     av_freep(&rt->out_data);
yading@11:     ffurl_close(rt->stream);
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int rtmp_http_open(URLContext *h, const char *uri, int flags)
yading@11: {
yading@11:     RTMP_HTTPContext *rt = h->priv_data;
yading@11:     char headers[1024], url[1024];
yading@11:     int ret, off = 0;
yading@11: 
yading@11:     av_url_split(NULL, 0, NULL, 0, rt->host, sizeof(rt->host), &rt->port,
yading@11:                  NULL, 0, uri);
yading@11: 
yading@11:     /* This is the first request that is sent to the server in order to
yading@11:      * register a client on the server and start a new session. The server
yading@11:      * replies with a unique id (usually a number) that is used by the client
yading@11:      * for all future requests.
yading@11:      * Note: the reply doesn't contain a value for the polling interval.
yading@11:      * A successful connect resets the consecutive index that is used
yading@11:      * in the URLs. */
yading@11:     if (rt->tls) {
yading@11:         if (rt->port < 0)
yading@11:             rt->port = RTMPTS_DEFAULT_PORT;
yading@11:         ff_url_join(url, sizeof(url), "https", NULL, rt->host, rt->port, "/open/1");
yading@11:     } else {
yading@11:         if (rt->port < 0)
yading@11:             rt->port = RTMPT_DEFAULT_PORT;
yading@11:         ff_url_join(url, sizeof(url), "http", NULL, rt->host, rt->port, "/open/1");
yading@11:     }
yading@11: 
yading@11:     /* alloc the http context */
yading@11:     if ((ret = ffurl_alloc(&rt->stream, url, AVIO_FLAG_READ_WRITE, NULL)) < 0)
yading@11:         goto fail;
yading@11: 
yading@11:     /* set options */
yading@11:     snprintf(headers, sizeof(headers),
yading@11:              "Cache-Control: no-cache\r\n"
yading@11:              "Content-type: application/x-fcs\r\n"
yading@11:              "User-Agent: Shockwave Flash\r\n");
yading@11:     av_opt_set(rt->stream->priv_data, "headers", headers, 0);
yading@11:     av_opt_set(rt->stream->priv_data, "multiple_requests", "1", 0);
yading@11:     av_opt_set_bin(rt->stream->priv_data, "post_data", "", 1, 0);
yading@11: 
yading@11:     /* open the http context */
yading@11:     if ((ret = ffurl_connect(rt->stream, NULL)) < 0)
yading@11:         goto fail;
yading@11: 
yading@11:     /* read the server reply which contains a unique ID */
yading@11:     for (;;) {
yading@11:         ret = ffurl_read(rt->stream, rt->client_id + off, sizeof(rt->client_id) - off);
yading@11:         if (ret == AVERROR_EOF)
yading@11:             break;
yading@11:         if (ret < 0)
yading@11:             goto fail;
yading@11:         off += ret;
yading@11:         if (off == sizeof(rt->client_id)) {
yading@11:             ret = AVERROR(EIO);
yading@11:             goto fail;
yading@11:         }
yading@11:     }
yading@11:     while (off > 0 && av_isspace(rt->client_id[off - 1]))
yading@11:         off--;
yading@11:     rt->client_id[off] = '\0';
yading@11: 
yading@11:     /* http context is now initialized */
yading@11:     rt->initialized = 1;
yading@11:     return 0;
yading@11: 
yading@11: fail:
yading@11:     rtmp_http_close(h);
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: #define OFFSET(x) offsetof(RTMP_HTTPContext, x)
yading@11: #define DEC AV_OPT_FLAG_DECODING_PARAM
yading@11: 
yading@11: static const AVOption ffrtmphttp_options[] = {
yading@11:     {"ffrtmphttp_tls", "Use a HTTPS tunneling connection (RTMPTS).", OFFSET(tls), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC},
yading@11:     { NULL },
yading@11: };
yading@11: 
yading@11: static const AVClass ffrtmphttp_class = {
yading@11:     .class_name = "ffrtmphttp",
yading@11:     .item_name  = av_default_item_name,
yading@11:     .option     = ffrtmphttp_options,
yading@11:     .version    = LIBAVUTIL_VERSION_INT,
yading@11: };
yading@11: 
yading@11: URLProtocol ff_ffrtmphttp_protocol = {
yading@11:     .name           = "ffrtmphttp",
yading@11:     .url_open       = rtmp_http_open,
yading@11:     .url_read       = rtmp_http_read,
yading@11:     .url_write      = rtmp_http_write,
yading@11:     .url_close      = rtmp_http_close,
yading@11:     .priv_data_size = sizeof(RTMP_HTTPContext),
yading@11:     .flags          = URL_PROTOCOL_FLAG_NETWORK,
yading@11:     .priv_data_class= &ffrtmphttp_class,
yading@11: };