/* * MMS protocol over HTTP * Copyright (c) 2010 Zhentan Feng * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /* * Reference * Windows Media HTTP Streaming Protocol. * http://msdn.microsoft.com/en-us/library/cc251059(PROT.10).aspx */ #include #include "libavutil/intreadwrite.h" #include "libavutil/avstring.h" #include "libavutil/opt.h" #include "internal.h" #include "mms.h" #include "asf.h" #include "http.h" #include "url.h" #define CHUNK_HEADER_LENGTH 4 // 2bytes chunk type and 2bytes chunk length. #define EXT_HEADER_LENGTH 8 // 4bytes sequence, 2bytes useless and 2bytes chunk length. // see Ref 2.2.1.8 #define USERAGENT "User-Agent: NSPlayer/4.1.0.3856\r\n" // see Ref 2.2.1.4.33 // the guid value can be changed to any valid value. #define CLIENTGUID "Pragma: xClientGUID={c77e7400-738a-11d2-9add-0020af0a3278}\r\n" // see Ref 2.2.3 for packet type define: // chunk type contains 2 fields: Frame and PacketID. // Frame is 0x24 or 0xA4(rarely), different PacketID indicates different packet type. typedef enum { CHUNK_TYPE_DATA = 0x4424, CHUNK_TYPE_ASF_HEADER = 0x4824, CHUNK_TYPE_END = 0x4524, CHUNK_TYPE_STREAM_CHANGE = 0x4324, } ChunkType; typedef struct { MMSContext mms; int request_seq; ///< request packet sequence int chunk_seq; ///< data packet sequence } MMSHContext; static int mmsh_close(URLContext *h) { MMSHContext *mmsh = (MMSHContext *)h->priv_data; MMSContext *mms = &mmsh->mms; if (mms->mms_hd) ffurl_close(mms->mms_hd); av_free(mms->streams); av_free(mms->asf_header); return 0; } static ChunkType get_chunk_header(MMSHContext *mmsh, int *len) { MMSContext *mms = &mmsh->mms; uint8_t chunk_header[CHUNK_HEADER_LENGTH]; uint8_t ext_header[EXT_HEADER_LENGTH]; ChunkType chunk_type; int chunk_len, res, ext_header_len; res = ffurl_read_complete(mms->mms_hd, chunk_header, CHUNK_HEADER_LENGTH); if (res != CHUNK_HEADER_LENGTH) { av_log(NULL, AV_LOG_ERROR, "Read data packet header failed!\n"); return AVERROR(EIO); } chunk_type = AV_RL16(chunk_header); chunk_len = AV_RL16(chunk_header + 2); switch (chunk_type) { case CHUNK_TYPE_END: case CHUNK_TYPE_STREAM_CHANGE: ext_header_len = 4; break; case CHUNK_TYPE_ASF_HEADER: case CHUNK_TYPE_DATA: ext_header_len = 8; break; default: av_log(NULL, AV_LOG_ERROR, "Strange chunk type %d\n", chunk_type); return AVERROR_INVALIDDATA; } res = ffurl_read_complete(mms->mms_hd, ext_header, ext_header_len); if (res != ext_header_len) { av_log(NULL, AV_LOG_ERROR, "Read ext header failed!\n"); return AVERROR(EIO); } *len = chunk_len - ext_header_len; if (chunk_type == CHUNK_TYPE_END || chunk_type == CHUNK_TYPE_DATA) mmsh->chunk_seq = AV_RL32(ext_header); return chunk_type; } static int read_data_packet(MMSHContext *mmsh, const int len) { MMSContext *mms = &mmsh->mms; int res; if (len > sizeof(mms->in_buffer)) { av_log(NULL, AV_LOG_ERROR, "Data packet length %d exceeds the in_buffer size %zu\n", len, sizeof(mms->in_buffer)); return AVERROR(EIO); } res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len); av_dlog(NULL, "Data packet len = %d\n", len); if (res != len) { av_log(NULL, AV_LOG_ERROR, "Read data packet failed!\n"); return AVERROR(EIO); } if (len > mms->asf_packet_len) { av_log(NULL, AV_LOG_ERROR, "Chunk length %d exceed packet length %d\n",len, mms->asf_packet_len); return AVERROR_INVALIDDATA; } else { memset(mms->in_buffer + len, 0, mms->asf_packet_len - len); // padding } mms->read_in_ptr = mms->in_buffer; mms->remaining_in_len = mms->asf_packet_len; return 0; } static int get_http_header_data(MMSHContext *mmsh) { MMSContext *mms = &mmsh->mms; int res, len; ChunkType chunk_type; for (;;) { len = 0; res = chunk_type = get_chunk_header(mmsh, &len); if (res < 0) { return res; } else if (chunk_type == CHUNK_TYPE_ASF_HEADER){ // get asf header and stored it if (!mms->header_parsed) { if (mms->asf_header) { if (len != mms->asf_header_size) { mms->asf_header_size = len; av_dlog(NULL, "Header len changed from %d to %d\n", mms->asf_header_size, len); av_freep(&mms->asf_header); } } mms->asf_header = av_mallocz(len); if (!mms->asf_header) { return AVERROR(ENOMEM); } mms->asf_header_size = len; } if (len > mms->asf_header_size) { av_log(NULL, AV_LOG_ERROR, "Asf header packet len = %d exceed the asf header buf size %d\n", len, mms->asf_header_size); return AVERROR(EIO); } res = ffurl_read_complete(mms->mms_hd, mms->asf_header, len); if (res != len) { av_log(NULL, AV_LOG_ERROR, "Recv asf header data len %d != expected len %d\n", res, len); return AVERROR(EIO); } mms->asf_header_size = len; if (!mms->header_parsed) { res = ff_mms_asf_header_parser(mms); mms->header_parsed = 1; return res; } } else if (chunk_type == CHUNK_TYPE_DATA) { // read data packet and do padding return read_data_packet(mmsh, len); } else { if (len) { if (len > sizeof(mms->in_buffer)) { av_log(NULL, AV_LOG_ERROR, "Other packet len = %d exceed the in_buffer size %zu\n", len, sizeof(mms->in_buffer)); return AVERROR(EIO); } res = ffurl_read_complete(mms->mms_hd, mms->in_buffer, len); if (res != len) { av_log(NULL, AV_LOG_ERROR, "Read other chunk type data failed!\n"); return AVERROR(EIO); } else { av_dlog(NULL, "Skip chunk type %d \n", chunk_type); continue; } } } } } static int mmsh_open(URLContext *h, const char *uri, int flags) { int i, port, err; char httpname[256], path[256], host[128], location[1024]; char *stream_selection = NULL; char headers[1024]; MMSHContext *mmsh = h->priv_data; MMSContext *mms; mmsh->request_seq = h->is_streamed = 1; mms = &mmsh->mms; av_strlcpy(location, uri, sizeof(location)); av_url_split(NULL, 0, NULL, 0, host, sizeof(host), &port, path, sizeof(path), location); if (port<0) port = 80; // default mmsh protocol port ff_url_join(httpname, sizeof(httpname), "http", NULL, host, port, "%s", path); if (ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ, &h->interrupt_callback) < 0) { return AVERROR(EIO); } snprintf(headers, sizeof(headers), "Accept: */*\r\n" USERAGENT "Host: %s:%d\r\n" "Pragma: no-cache,rate=1.000000,stream-time=0," "stream-offset=0:0,request-context=%u,max-duration=0\r\n" CLIENTGUID "Connection: Close\r\n\r\n", host, port, mmsh->request_seq++); av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0); err = ffurl_connect(mms->mms_hd, NULL); if (err) { goto fail; } err = get_http_header_data(mmsh); if (err) { av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n"); goto fail; } // close the socket and then reopen it for sending the second play request. ffurl_close(mms->mms_hd); memset(headers, 0, sizeof(headers)); if ((err = ffurl_alloc(&mms->mms_hd, httpname, AVIO_FLAG_READ, &h->interrupt_callback)) < 0) { goto fail; } stream_selection = av_mallocz(mms->stream_num * 19 + 1); if (!stream_selection) return AVERROR(ENOMEM); for (i = 0; i < mms->stream_num; i++) { char tmp[20]; err = snprintf(tmp, sizeof(tmp), "ffff:%d:0 ", mms->streams[i].id); if (err < 0) goto fail; av_strlcat(stream_selection, tmp, mms->stream_num * 19 + 1); } // send play request err = snprintf(headers, sizeof(headers), "Accept: */*\r\n" USERAGENT "Host: %s:%d\r\n" "Pragma: no-cache,rate=1.000000,request-context=%u\r\n" "Pragma: xPlayStrm=1\r\n" CLIENTGUID "Pragma: stream-switch-count=%d\r\n" "Pragma: stream-switch-entry=%s\r\n" "Connection: Close\r\n\r\n", host, port, mmsh->request_seq++, mms->stream_num, stream_selection); av_freep(&stream_selection); if (err < 0) { av_log(NULL, AV_LOG_ERROR, "Build play request failed!\n"); goto fail; } av_dlog(NULL, "out_buffer is %s", headers); av_opt_set(mms->mms_hd->priv_data, "headers", headers, 0); err = ffurl_connect(mms->mms_hd, NULL); if (err) { goto fail; } err = get_http_header_data(mmsh); if (err) { av_log(NULL, AV_LOG_ERROR, "Get http header data failed!\n"); goto fail; } av_dlog(NULL, "Connection successfully open\n"); return 0; fail: av_freep(&stream_selection); mmsh_close(h); av_dlog(NULL, "Connection failed with error %d\n", err); return err; } static int handle_chunk_type(MMSHContext *mmsh) { MMSContext *mms = &mmsh->mms; int res, len = 0; ChunkType chunk_type; chunk_type = get_chunk_header(mmsh, &len); switch (chunk_type) { case CHUNK_TYPE_END: mmsh->chunk_seq = 0; av_log(NULL, AV_LOG_ERROR, "Stream ended!\n"); return AVERROR(EIO); case CHUNK_TYPE_STREAM_CHANGE: mms->header_parsed = 0; if (res = get_http_header_data(mmsh)) { av_log(NULL, AV_LOG_ERROR,"Stream changed! Failed to get new header!\n"); return res; } break; case CHUNK_TYPE_DATA: return read_data_packet(mmsh, len); default: av_log(NULL, AV_LOG_ERROR, "Recv other type packet %d\n", chunk_type); return AVERROR_INVALIDDATA; } return 0; } static int mmsh_read(URLContext *h, uint8_t *buf, int size) { int res = 0; MMSHContext *mmsh = h->priv_data; MMSContext *mms = &mmsh->mms; do { if (mms->asf_header_read_size < mms->asf_header_size) { // copy asf header into buffer res = ff_mms_read_header(mms, buf, size); } else { if (!mms->remaining_in_len && (res = handle_chunk_type(mmsh))) return res; res = ff_mms_read_data(mms, buf, size); } } while (!res); return res; } URLProtocol ff_mmsh_protocol = { .name = "mmsh", .url_open = mmsh_open, .url_read = mmsh_read, .url_close = mmsh_close, .priv_data_size = sizeof(MMSHContext), };