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FFmpeg4/libavformat/mmst.c

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2023-07-02 12:20:28 +00:00
/*
* MMS protocol over TCP
* Copyright (c) 2006,2007 Ryan Martell
* Copyright (c) 2007 Björn Axelsson
* Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* References
* MMS protocol specification:
* [1]http://msdn.microsoft.com/en-us/library/cc234711(PROT.10).aspx
* ASF specification. Revision 01.20.03.
* [2]http://msdn.microsoft.com/en-us/library/bb643323.aspx
*/
#include "avformat.h"
#include "mms.h"
#include "internal.h"
#include "avio_internal.h"
#include "libavutil/intreadwrite.h"
#include "libavcodec/bytestream.h"
#include "network.h"
#include "url.h"
#define LOCAL_ADDRESS 0xc0a80081 // FIXME get and use correct local ip address.
#define LOCAL_PORT 1037 // as above.
/** Client to server packet types. */
typedef enum {
CS_PKT_INITIAL = 0x01,
CS_PKT_PROTOCOL_SELECT = 0x02,
CS_PKT_MEDIA_FILE_REQUEST = 0x05,
CS_PKT_START_FROM_PKT_ID = 0x07,
CS_PKT_STREAM_PAUSE = 0x09,
CS_PKT_STREAM_CLOSE = 0x0d,
CS_PKT_MEDIA_HEADER_REQUEST = 0x15,
CS_PKT_TIMING_DATA_REQUEST = 0x18,
CS_PKT_USER_PASSWORD = 0x1a,
CS_PKT_KEEPALIVE = 0x1b,
CS_PKT_STREAM_ID_REQUEST = 0x33,
} MMSCSPacketType;
/** Server to client packet types. */
typedef enum {
/** Control packets. */
/*@{*/
SC_PKT_CLIENT_ACCEPTED = 0x01,
SC_PKT_PROTOCOL_ACCEPTED = 0x02,
SC_PKT_PROTOCOL_FAILED = 0x03,
SC_PKT_MEDIA_PKT_FOLLOWS = 0x05,
SC_PKT_MEDIA_FILE_DETAILS = 0x06,
SC_PKT_HEADER_REQUEST_ACCEPTED = 0x11,
SC_PKT_TIMING_TEST_REPLY = 0x15,
SC_PKT_PASSWORD_REQUIRED = 0x1a,
SC_PKT_KEEPALIVE = 0x1b,
SC_PKT_STREAM_STOPPED = 0x1e,
SC_PKT_STREAM_CHANGING = 0x20,
SC_PKT_STREAM_ID_ACCEPTED = 0x21,
/*@}*/
/** Pseudo packets. */
/*@{*/
SC_PKT_CANCEL = -1,
SC_PKT_NO_DATA = -2,
/*@}*/
/** Data packets. */
/*@{*/
SC_PKT_ASF_HEADER = 0x010000,// make it bigger than 0xFF in case of
SC_PKT_ASF_MEDIA = 0x010001,// receiving false data packets.
/*@}*/
} MMSSCPacketType;
typedef struct MMSTContext {
MMSContext mms;
int outgoing_packet_seq; ///< Outgoing packet sequence number.
char path[256]; ///< Path of the resource being asked for.
char host[128]; ///< Host of the resources.
int incoming_packet_seq; ///< Incoming packet sequence number.
int incoming_flags; ///< Incoming packet flags.
int packet_id; ///< Identifier for packets in the current stream.
unsigned int header_packet_id; ///< default is 2.
} MMSTContext;
/** Create MMST command packet header */
static void start_command_packet(MMSTContext *mmst, MMSCSPacketType packet_type)
{
MMSContext *mms = &mmst->mms;
mms->write_out_ptr = mms->out_buffer;
bytestream_put_le32(&mms->write_out_ptr, 1); // start sequence
bytestream_put_le32(&mms->write_out_ptr, 0xb00bface);
bytestream_put_le32(&mms->write_out_ptr, 0); // Length starts from after the protocol type bytes
bytestream_put_le32(&mms->write_out_ptr, MKTAG('M','M','S',' '));
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, mmst->outgoing_packet_seq++);
bytestream_put_le64(&mms->write_out_ptr, 0); // timestamp
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le16(&mms->write_out_ptr, packet_type);
bytestream_put_le16(&mms->write_out_ptr, 3); // direction to server
}
/** Add prefixes to MMST command packet. */
static void insert_command_prefixes(MMSContext *mms,
uint32_t prefix1, uint32_t prefix2)
{
bytestream_put_le32(&mms->write_out_ptr, prefix1); // first prefix
bytestream_put_le32(&mms->write_out_ptr, prefix2); // second prefix
}
/** Send a prepared MMST command packet. */
static int send_command_packet(MMSTContext *mmst)
{
MMSContext *mms = &mmst->mms;
int len= mms->write_out_ptr - mms->out_buffer;
int exact_length = FFALIGN(len, 8);
int first_length= exact_length - 16;
int len8= first_length/8;
int write_result;
// update packet length fields.
AV_WL32(mms->out_buffer + 8, first_length);
AV_WL32(mms->out_buffer + 16, len8);
AV_WL32(mms->out_buffer + 32, len8-2);
memset(mms->write_out_ptr, 0, exact_length - len);
// write it out.
write_result= ffurl_write(mms->mms_hd, mms->out_buffer, exact_length);
if(write_result != exact_length) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Failed to write data of length %d: %d (%s)\n",
exact_length, write_result,
write_result < 0 ? strerror(AVUNERROR(write_result)) :
"The server closed the connection");
return AVERROR(EIO);
}
return 0;
}
static int mms_put_utf16(MMSContext *mms, const uint8_t *src)
{
AVIOContext bic;
int size = mms->write_out_ptr - mms->out_buffer;
int len;
ffio_init_context(&bic, mms->write_out_ptr,
sizeof(mms->out_buffer) - size, 1, NULL, NULL, NULL, NULL);
len = avio_put_str16le(&bic, src);
if (len < 0)
return len;
mms->write_out_ptr += len;
return 0;
}
static int send_time_test_data(MMSTContext *mmst)
{
start_command_packet(mmst, CS_PKT_TIMING_DATA_REQUEST);
insert_command_prefixes(&mmst->mms, 0x00f0f0f0, 0x0004000b);
return send_command_packet(mmst);
}
static int send_protocol_select(MMSTContext *mmst)
{
int ret;
char data_string[256];
MMSContext *mms = &mmst->mms;
start_command_packet(mmst, CS_PKT_PROTOCOL_SELECT);
insert_command_prefixes(mms, 0, 0xffffffff);
bytestream_put_le32(&mms->write_out_ptr, 0); // maxFunnelBytes
bytestream_put_le32(&mms->write_out_ptr, 0x00989680); // maxbitRate
bytestream_put_le32(&mms->write_out_ptr, 2); // funnelMode
snprintf(data_string, sizeof(data_string), "\\\\%d.%d.%d.%d\\%s\\%d",
(LOCAL_ADDRESS>>24)&0xff,
(LOCAL_ADDRESS>>16)&0xff,
(LOCAL_ADDRESS>>8)&0xff,
LOCAL_ADDRESS&0xff,
"TCP", // or UDP
LOCAL_PORT);
if ((ret = mms_put_utf16(mms, data_string)) < 0)
return ret;
return send_command_packet(mmst);
}
static int send_media_file_request(MMSTContext *mmst)
{
int ret;
MMSContext *mms = &mmst->mms;
start_command_packet(mmst, CS_PKT_MEDIA_FILE_REQUEST);
insert_command_prefixes(mms, 1, 0xffffffff);
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, 0);
if ((ret = mms_put_utf16(mms, mmst->path + 1)) < 0) // +1 for skip "/"
return ret;
return send_command_packet(mmst);
}
static void handle_packet_stream_changing_type(MMSTContext *mmst)
{
MMSContext *mms = &mmst->mms;
av_log(mms->mms_hd, AV_LOG_TRACE, "Stream changing!\n");
// 40 is the packet header size, 7 is the prefix size.
mmst->header_packet_id= AV_RL32(mms->in_buffer + 40 + 7);
av_log(mms->mms_hd, AV_LOG_TRACE, "Changed header prefix to 0x%x", mmst->header_packet_id);
}
static int send_keepalive_packet(MMSTContext *mmst)
{
// respond to a keepalive with a keepalive...
start_command_packet(mmst, CS_PKT_KEEPALIVE);
insert_command_prefixes(&mmst->mms, 1, 0x100FFFF);
return send_command_packet(mmst);
}
/** Pad media packets smaller than max_packet_size and/or adjust read position
* after a seek. */
static void pad_media_packet(MMSContext *mms)
{
if(mms->remaining_in_len<mms->asf_packet_len) {
int padding_size = mms->asf_packet_len - mms->remaining_in_len;
memset(mms->in_buffer + mms->remaining_in_len, 0, padding_size);
mms->remaining_in_len += padding_size;
}
}
/** Read incoming MMST media, header or command packet. */
static MMSSCPacketType get_tcp_server_response(MMSTContext *mmst)
{
int read_result;
MMSSCPacketType packet_type= -1;
MMSContext *mms = &mmst->mms;
for(;;) {
read_result = ffurl_read_complete(mms->mms_hd, mms->in_buffer, 8);
if (read_result != 8) {
if(read_result < 0) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Error reading packet header: %d (%s)\n",
read_result, strerror(AVUNERROR(read_result)));
packet_type = SC_PKT_CANCEL;
} else {
av_log(mms->mms_hd, AV_LOG_ERROR,
"The server closed the connection\n");
packet_type = SC_PKT_NO_DATA;
}
return packet_type;
}
// handle command packet.
if(AV_RL32(mms->in_buffer + 4)==0xb00bface) {
int length_remaining, hr;
mmst->incoming_flags= mms->in_buffer[3];
read_result= ffurl_read_complete(mms->mms_hd, mms->in_buffer+8, 4);
if(read_result != 4) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Reading command packet length failed: %d (%s)\n",
read_result,
read_result < 0 ? strerror(AVUNERROR(read_result)) :
"The server closed the connection");
return read_result < 0 ? read_result : AVERROR(EIO);
}
length_remaining= AV_RL32(mms->in_buffer+8) + 4;
av_log(mms->mms_hd, AV_LOG_TRACE, "Length remaining is %d\n", length_remaining);
// read the rest of the packet.
if (length_remaining < 0
|| length_remaining > sizeof(mms->in_buffer) - 12) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Incoming packet length %d exceeds bufsize %"SIZE_SPECIFIER"\n",
length_remaining, sizeof(mms->in_buffer) - 12);
return AVERROR_INVALIDDATA;
}
read_result = ffurl_read_complete(mms->mms_hd, mms->in_buffer + 12,
length_remaining) ;
if (read_result != length_remaining) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Reading pkt data (length=%d) failed: %d (%s)\n",
length_remaining, read_result,
read_result < 0 ? strerror(AVUNERROR(read_result)) :
"The server closed the connection");
return read_result < 0 ? read_result : AVERROR(EIO);
}
packet_type= AV_RL16(mms->in_buffer+36);
if (read_result >= 44 && (hr = AV_RL32(mms->in_buffer + 40))) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Server sent a message with packet type 0x%x and error status code 0x%08x\n", packet_type, hr);
return AVERROR(EINVAL);
}
} else {
int length_remaining;
int packet_id_type;
int tmp;
// note we cache the first 8 bytes,
// then fill up the buffer with the others
tmp = AV_RL16(mms->in_buffer + 6);
length_remaining = (tmp - 8) & 0xffff;
mmst->incoming_packet_seq = AV_RL32(mms->in_buffer);
packet_id_type = mms->in_buffer[4];
mmst->incoming_flags = mms->in_buffer[5];
if (length_remaining < 0
|| length_remaining > sizeof(mms->in_buffer) - 8) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Data length %d is invalid or too large (max=%"SIZE_SPECIFIER")\n",
length_remaining, sizeof(mms->in_buffer));
return AVERROR_INVALIDDATA;
}
mms->remaining_in_len = length_remaining;
mms->read_in_ptr = mms->in_buffer;
read_result= ffurl_read_complete(mms->mms_hd, mms->in_buffer, length_remaining);
if(read_result != length_remaining) {
av_log(mms->mms_hd, AV_LOG_ERROR,
"Failed to read packet data of size %d: %d (%s)\n",
length_remaining, read_result,
read_result < 0 ? strerror(AVUNERROR(read_result)) :
"The server closed the connection");
return read_result < 0 ? read_result : AVERROR(EIO);
}
// if we successfully read everything.
if(packet_id_type == mmst->header_packet_id) {
int err;
packet_type = SC_PKT_ASF_HEADER;
// Store the asf header
if(!mms->header_parsed) {
if ((err = av_reallocp(&mms->asf_header,
mms->asf_header_size +
mms->remaining_in_len)) < 0) {
mms->asf_header_size = 0;
return err;
}
memcpy(mms->asf_header + mms->asf_header_size,
mms->read_in_ptr, mms->remaining_in_len);
mms->asf_header_size += mms->remaining_in_len;
}
// 0x04 means asf header is sent in multiple packets.
if (mmst->incoming_flags == 0x04)
continue;
} else if(packet_id_type == mmst->packet_id) {
packet_type = SC_PKT_ASF_MEDIA;
} else {
av_log(mms->mms_hd, AV_LOG_TRACE, "packet id type %d is old.", packet_id_type);
continue;
}
}
// preprocess some packet type
if(packet_type == SC_PKT_KEEPALIVE) {
send_keepalive_packet(mmst);
continue;
} else if(packet_type == SC_PKT_STREAM_CHANGING) {
handle_packet_stream_changing_type(mmst);
} else if(packet_type == SC_PKT_ASF_MEDIA) {
pad_media_packet(mms);
}
return packet_type;
}
}
static int mms_safe_send_recv(MMSTContext *mmst,
int (*send_fun)(MMSTContext *mmst),
const MMSSCPacketType expect_type)
{
MMSSCPacketType type;
if(send_fun) {
int ret = send_fun(mmst);
if (ret < 0) {
av_log(NULL, AV_LOG_TRACE, "Send Packet error before expecting recv packet %d\n", expect_type);
return ret;
}
}
if ((type = get_tcp_server_response(mmst)) != expect_type) {
av_log(NULL, AV_LOG_ERROR,
"Corrupt stream (unexpected packet type 0x%x, expected 0x%x)\n",
type, expect_type);
return AVERROR_INVALIDDATA;
} else {
return 0;
}
}
static int send_media_header_request(MMSTContext *mmst)
{
MMSContext *mms = &mmst->mms;
start_command_packet(mmst, CS_PKT_MEDIA_HEADER_REQUEST);
insert_command_prefixes(mms, 1, 0);
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, 0x00800000);
bytestream_put_le32(&mms->write_out_ptr, 0xffffffff);
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, 0);
// the media preroll value in milliseconds?
bytestream_put_le32(&mms->write_out_ptr, 0);
bytestream_put_le32(&mms->write_out_ptr, 0x40AC2000);
bytestream_put_le32(&mms->write_out_ptr, 2);
bytestream_put_le32(&mms->write_out_ptr, 0);
return send_command_packet(mmst);
}
/** Send the initial handshake. */
static int send_startup_packet(MMSTContext *mmst)
{
char data_string[256];
int ret;
MMSContext *mms = &mmst->mms;
// SubscriberName is defined in MS specification linked below.
// The GUID value can be any valid value.
// http://download.microsoft.com/
// download/9/5/E/95EF66AF-9026-4BB0-A41D-A4F81802D92C/%5BMS-WMSP%5D.pdf
snprintf(data_string, sizeof(data_string),
"NSPlayer/7.0.0.1956; {%s}; Host: %s",
"7E667F5D-A661-495E-A512-F55686DDA178", mmst->host);
start_command_packet(mmst, CS_PKT_INITIAL);
insert_command_prefixes(mms, 0, 0x0004000b);
bytestream_put_le32(&mms->write_out_ptr, 0x0003001c);
if ((ret = mms_put_utf16(mms, data_string)) < 0)
return ret;
return send_command_packet(mmst);
}
/** Send MMST stream selection command based on the AVStream->discard values. */
static int send_stream_selection_request(MMSTContext *mmst)
{
int i;
MMSContext *mms = &mmst->mms;
// send the streams we want back...
start_command_packet(mmst, CS_PKT_STREAM_ID_REQUEST);
bytestream_put_le32(&mms->write_out_ptr, mms->stream_num); // stream nums
for(i= 0; i<mms->stream_num; i++) {
bytestream_put_le16(&mms->write_out_ptr, 0xffff); // flags
bytestream_put_le16(&mms->write_out_ptr, mms->streams[i].id); // stream id
bytestream_put_le16(&mms->write_out_ptr, 0); // selection
}
return send_command_packet(mmst);
}
static int send_close_packet(MMSTContext *mmst)
{
start_command_packet(mmst, CS_PKT_STREAM_CLOSE);
insert_command_prefixes(&mmst->mms, 1, 1);
return send_command_packet(mmst);
}
/** Close the MMSH/MMST connection */
static int mms_close(URLContext *h)
{
MMSTContext *mmst = (MMSTContext *)h->priv_data;
MMSContext *mms = &mmst->mms;
if(mms->mms_hd) {
send_close_packet(mmst);
ffurl_closep(&mms->mms_hd);
}
/* free all separately allocated pointers in mms */
av_freep(&mms->streams);
av_freep(&mms->asf_header);
return 0;
}
static int send_media_packet_request(MMSTContext *mmst)
{
MMSContext *mms = &mmst->mms;
start_command_packet(mmst, CS_PKT_START_FROM_PKT_ID);
insert_command_prefixes(mms, 1, 0x0001FFFF);
bytestream_put_le64(&mms->write_out_ptr, 0); // seek timestamp
bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // unknown
bytestream_put_le32(&mms->write_out_ptr, 0xffffffff); // packet offset
bytestream_put_byte(&mms->write_out_ptr, 0xff); // max stream time limit
bytestream_put_byte(&mms->write_out_ptr, 0xff); // max stream time limit
bytestream_put_byte(&mms->write_out_ptr, 0xff); // max stream time limit
bytestream_put_byte(&mms->write_out_ptr, 0x00); // stream time limit flag
mmst->packet_id++; // new packet_id
bytestream_put_le32(&mms->write_out_ptr, mmst->packet_id);
return send_command_packet(mmst);
}
static void clear_stream_buffers(MMSContext *mms)
{
mms->remaining_in_len = 0;
mms->read_in_ptr = mms->in_buffer;
}
static int mms_open(URLContext *h, const char *uri, int flags)
{
MMSTContext *mmst = h->priv_data;
MMSContext *mms;
int port, err;
char tcpname[256];
h->is_streamed = 1;
mms = &mmst->mms;
// only for MMS over TCP, so set proto = NULL
av_url_split(NULL, 0, NULL, 0,
mmst->host, sizeof(mmst->host), &port, mmst->path,
sizeof(mmst->path), uri);
if(port<0)
port = 1755; // default MMS protocol port
// establish tcp connection.
ff_url_join(tcpname, sizeof(tcpname), "tcp", NULL, mmst->host, port, NULL);
err = ffurl_open_whitelist(&mms->mms_hd, tcpname, AVIO_FLAG_READ_WRITE,
&h->interrupt_callback, NULL,
h->protocol_whitelist, h->protocol_blacklist, h);
if (err)
goto fail;
mmst->packet_id = 3; // default, initial value.
mmst->header_packet_id = 2; // default, initial value.
err = mms_safe_send_recv(mmst, send_startup_packet, SC_PKT_CLIENT_ACCEPTED);
if (err)
goto fail;
err = mms_safe_send_recv(mmst, send_time_test_data, SC_PKT_TIMING_TEST_REPLY);
if (err)
goto fail;
err = mms_safe_send_recv(mmst, send_protocol_select, SC_PKT_PROTOCOL_ACCEPTED);
if (err)
goto fail;
err = mms_safe_send_recv(mmst, send_media_file_request, SC_PKT_MEDIA_FILE_DETAILS);
if (err)
goto fail;
err = mms_safe_send_recv(mmst, send_media_header_request, SC_PKT_HEADER_REQUEST_ACCEPTED);
if (err)
goto fail;
err = mms_safe_send_recv(mmst, NULL, SC_PKT_ASF_HEADER);
if (err)
goto fail;
if((mmst->incoming_flags != 0X08) && (mmst->incoming_flags != 0X0C)) {
av_log(h, AV_LOG_ERROR,
"The server does not support MMST (try MMSH or RTSP)\n");
err = AVERROR(EINVAL);
goto fail;
}
err = ff_mms_asf_header_parser(mms);
if (err) {
av_log(h, AV_LOG_TRACE, "asf header parsed failed!\n");
goto fail;
}
mms->header_parsed = 1;
if (!mms->asf_packet_len || !mms->stream_num)
goto fail;
clear_stream_buffers(mms);
err = mms_safe_send_recv(mmst, send_stream_selection_request, SC_PKT_STREAM_ID_ACCEPTED);
if (err)
goto fail;
// send media packet request
err = mms_safe_send_recv(mmst, send_media_packet_request, SC_PKT_MEDIA_PKT_FOLLOWS);
if (err) {
goto fail;
}
av_log(h, AV_LOG_TRACE, "Leaving open (success)\n");
return 0;
fail:
mms_close(h);
av_log(mms->mms_hd, AV_LOG_TRACE, "Leaving open (failure: %d)\n", err);
return err;
}
/** Read ASF data through the protocol. */
static int mms_read(URLContext *h, uint8_t *buf, int size)
{
/* TODO: see tcp.c:tcp_read() about a possible timeout scheme */
MMSTContext *mmst = h->priv_data;
MMSContext *mms = &mmst->mms;
int result = 0;
do {
if(mms->asf_header_read_size < mms->asf_header_size) {
/* Read from ASF header buffer */
result = ff_mms_read_header(mms, buf, size);
} else if(mms->remaining_in_len) {
/* Read remaining packet data to buffer.
* the result can not be zero because remaining_in_len is positive.*/
result = ff_mms_read_data(mms, buf, size);
} else {
/* Read from network */
int err = mms_safe_send_recv(mmst, NULL, SC_PKT_ASF_MEDIA);
if (err == 0) {
if(mms->remaining_in_len>mms->asf_packet_len) {
av_log(h, AV_LOG_ERROR,
"Incoming pktlen %d is larger than ASF pktsize %d\n",
mms->remaining_in_len, mms->asf_packet_len);
result= AVERROR(EIO);
} else {
// copy the data to the packet buffer.
result = ff_mms_read_data(mms, buf, size);
if (result == 0) {
av_log(h, AV_LOG_TRACE, "Read ASF media packet size is zero!\n");
break;
}
}
} else {
av_log(h, AV_LOG_TRACE, "read packet error!\n");
break;
}
}
} while(!result); // only return one packet.
return result;
}
const URLProtocol ff_mmst_protocol = {
.name = "mmst",
.url_open = mms_open,
.url_read = mms_read,
.url_close = mms_close,
.priv_data_size = sizeof(MMSTContext),
.flags = URL_PROTOCOL_FLAG_NETWORK,
};