| /* |
| * Xiph RTP Protocols |
| * Copyright (c) 2009 Colin McQuillian |
| * Copyright (c) 2010 Josh Allmann |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * @brief Xiph / RTP Code |
| * @author Colin McQuillan <m.niloc@gmail.com> |
| * @author Josh Allmann <joshua.allmann@gmail.com> |
| */ |
| |
| #include "libavutil/avstring.h" |
| #include "libavutil/base64.h" |
| #include "libavcodec/bytestream.h" |
| |
| #include <assert.h> |
| |
| #include "rtpdec.h" |
| #include "rtpdec_formats.h" |
| |
| /** |
| * RTP/Xiph specific private data. |
| */ |
| struct PayloadContext { |
| unsigned ident; ///< 24-bit stream configuration identifier |
| uint32_t timestamp; |
| AVIOContext* fragment; ///< buffer for split payloads |
| uint8_t *split_buf; |
| int split_pos, split_buf_len, split_buf_size; |
| int split_pkts; |
| }; |
| |
| static PayloadContext *xiph_new_context(void) |
| { |
| return av_mallocz(sizeof(PayloadContext)); |
| } |
| |
| static inline void free_fragment_if_needed(PayloadContext * data) |
| { |
| if (data->fragment) { |
| uint8_t* p; |
| avio_close_dyn_buf(data->fragment, &p); |
| av_free(p); |
| data->fragment = NULL; |
| } |
| } |
| |
| static void xiph_free_context(PayloadContext * data) |
| { |
| free_fragment_if_needed(data); |
| av_free(data->split_buf); |
| av_free(data); |
| } |
| |
| static int xiph_handle_packet(AVFormatContext * ctx, |
| PayloadContext * data, |
| AVStream * st, |
| AVPacket * pkt, |
| uint32_t * timestamp, |
| const uint8_t * buf, int len, int flags) |
| { |
| |
| int ident, fragmented, tdt, num_pkts, pkt_len; |
| |
| if (!buf) { |
| if (!data->split_buf || data->split_pos + 2 > data->split_buf_len || |
| data->split_pkts <= 0) { |
| av_log(ctx, AV_LOG_ERROR, "No more data to return\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| pkt_len = AV_RB16(data->split_buf + data->split_pos); |
| data->split_pos += 2; |
| if (data->split_pos + pkt_len > data->split_buf_len) { |
| av_log(ctx, AV_LOG_ERROR, "Not enough data to return\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| if (av_new_packet(pkt, pkt_len)) { |
| av_log(ctx, AV_LOG_ERROR, "Out of memory.\n"); |
| return AVERROR(ENOMEM); |
| } |
| pkt->stream_index = st->index; |
| memcpy(pkt->data, data->split_buf + data->split_pos, pkt_len); |
| data->split_pos += pkt_len; |
| data->split_pkts--; |
| return data->split_pkts > 0; |
| } |
| |
| if (len < 6) { |
| av_log(ctx, AV_LOG_ERROR, "Invalid %d byte packet\n", len); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| // read xiph rtp headers |
| ident = AV_RB24(buf); |
| fragmented = buf[3] >> 6; |
| tdt = (buf[3] >> 4) & 3; |
| num_pkts = buf[3] & 0xf; |
| pkt_len = AV_RB16(buf + 4); |
| |
| if (pkt_len > len - 6) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Invalid packet length %d in %d byte packet\n", pkt_len, |
| len); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| if (ident != data->ident) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Unimplemented Xiph SDP configuration change detected\n"); |
| return AVERROR_PATCHWELCOME; |
| } |
| |
| if (tdt) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Unimplemented RTP Xiph packet settings (%d,%d,%d)\n", |
| fragmented, tdt, num_pkts); |
| return AVERROR_PATCHWELCOME; |
| } |
| |
| buf += 6; // move past header bits |
| len -= 6; |
| |
| if (fragmented == 0) { |
| if (av_new_packet(pkt, pkt_len)) { |
| av_log(ctx, AV_LOG_ERROR, "Out of memory.\n"); |
| return AVERROR(ENOMEM); |
| } |
| pkt->stream_index = st->index; |
| memcpy(pkt->data, buf, pkt_len); |
| buf += pkt_len; |
| len -= pkt_len; |
| num_pkts--; |
| |
| if (num_pkts > 0) { |
| if (len > data->split_buf_size || !data->split_buf) { |
| av_freep(&data->split_buf); |
| data->split_buf_size = 2 * len; |
| data->split_buf = av_malloc(data->split_buf_size); |
| if (!data->split_buf) { |
| av_log(ctx, AV_LOG_ERROR, "Out of memory.\n"); |
| av_free_packet(pkt); |
| return AVERROR(ENOMEM); |
| } |
| } |
| memcpy(data->split_buf, buf, len); |
| data->split_buf_len = len; |
| data->split_pos = 0; |
| data->split_pkts = num_pkts; |
| return 1; |
| } |
| |
| return 0; |
| |
| } else if (fragmented == 1) { |
| // start of xiph data fragment |
| int res; |
| |
| // end packet has been lost somewhere, so drop buffered data |
| free_fragment_if_needed(data); |
| |
| if((res = avio_open_dyn_buf(&data->fragment)) < 0) |
| return res; |
| |
| avio_write(data->fragment, buf, pkt_len); |
| data->timestamp = *timestamp; |
| |
| } else { |
| assert(fragmented < 4); |
| if (data->timestamp != *timestamp) { |
| // skip if fragmented timestamp is incorrect; |
| // a start packet has been lost somewhere |
| free_fragment_if_needed(data); |
| av_log(ctx, AV_LOG_ERROR, "RTP timestamps don't match!\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| if (!data->fragment) { |
| av_log(ctx, AV_LOG_WARNING, |
| "Received packet without a start fragment; dropping.\n"); |
| return AVERROR(EAGAIN); |
| } |
| |
| // copy data to fragment buffer |
| avio_write(data->fragment, buf, pkt_len); |
| |
| if (fragmented == 3) { |
| // end of xiph data packet |
| av_init_packet(pkt); |
| pkt->size = avio_close_dyn_buf(data->fragment, &pkt->data); |
| |
| if (pkt->size < 0) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Error occurred when getting fragment buffer."); |
| return pkt->size; |
| } |
| |
| pkt->stream_index = st->index; |
| pkt->destruct = av_destruct_packet; |
| |
| data->fragment = NULL; |
| |
| return 0; |
| } |
| } |
| |
| return AVERROR(EAGAIN); |
| } |
| |
| /** |
| * Length encoding described in RFC5215 section 3.1.1. |
| */ |
| static int get_base128(const uint8_t ** buf, const uint8_t * buf_end) |
| { |
| int n = 0; |
| for (; *buf < buf_end; ++*buf) { |
| n <<= 7; |
| n += **buf & 0x7f; |
| if (!(**buf & 0x80)) { |
| ++*buf; |
| return n; |
| } |
| } |
| return 0; |
| } |
| |
| /** |
| * Based off parse_packed_headers in Vorbis RTP |
| */ |
| static unsigned int |
| parse_packed_headers(const uint8_t * packed_headers, |
| const uint8_t * packed_headers_end, |
| AVCodecContext * codec, PayloadContext * xiph_data) |
| { |
| |
| unsigned num_packed, num_headers, length, length1, length2, extradata_alloc; |
| uint8_t *ptr; |
| |
| if (packed_headers_end - packed_headers < 9) { |
| av_log(codec, AV_LOG_ERROR, |
| "Invalid %td byte packed header.", |
| packed_headers_end - packed_headers); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| num_packed = bytestream_get_be32(&packed_headers); |
| xiph_data->ident = bytestream_get_be24(&packed_headers); |
| length = bytestream_get_be16(&packed_headers); |
| num_headers = get_base128(&packed_headers, packed_headers_end); |
| length1 = get_base128(&packed_headers, packed_headers_end); |
| length2 = get_base128(&packed_headers, packed_headers_end); |
| |
| if (num_packed != 1 || num_headers > 3) { |
| av_log(codec, AV_LOG_ERROR, |
| "Unimplemented number of headers: %d packed headers, %d headers\n", |
| num_packed, num_headers); |
| return AVERROR_PATCHWELCOME; |
| } |
| |
| if (packed_headers_end - packed_headers != length || |
| length1 > length || length2 > length - length1) { |
| av_log(codec, AV_LOG_ERROR, |
| "Bad packed header lengths (%d,%d,%td,%d)\n", length1, |
| length2, packed_headers_end - packed_headers, length); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* allocate extra space: |
| * -- length/255 +2 for xiphlacing |
| * -- one for the '2' marker |
| * -- FF_INPUT_BUFFER_PADDING_SIZE required */ |
| extradata_alloc = length + length/255 + 3 + FF_INPUT_BUFFER_PADDING_SIZE; |
| |
| ptr = codec->extradata = av_malloc(extradata_alloc); |
| if (!ptr) { |
| av_log(codec, AV_LOG_ERROR, "Out of memory\n"); |
| return AVERROR(ENOMEM); |
| } |
| *ptr++ = 2; |
| ptr += av_xiphlacing(ptr, length1); |
| ptr += av_xiphlacing(ptr, length2); |
| memcpy(ptr, packed_headers, length); |
| ptr += length; |
| codec->extradata_size = ptr - codec->extradata; |
| // clear out remaining parts of the buffer |
| memset(ptr, 0, extradata_alloc - codec->extradata_size); |
| |
| return 0; |
| } |
| |
| static int xiph_parse_fmtp_pair(AVStream* stream, |
| PayloadContext *xiph_data, |
| char *attr, char *value) |
| { |
| AVCodecContext *codec = stream->codec; |
| int result = 0; |
| |
| if (!strcmp(attr, "sampling")) { |
| if (!strcmp(value, "YCbCr-4:2:0")) { |
| codec->pix_fmt = PIX_FMT_YUV420P; |
| } else if (!strcmp(value, "YCbCr-4:4:2")) { |
| codec->pix_fmt = PIX_FMT_YUV422P; |
| } else if (!strcmp(value, "YCbCr-4:4:4")) { |
| codec->pix_fmt = PIX_FMT_YUV444P; |
| } else { |
| av_log(codec, AV_LOG_ERROR, |
| "Unsupported pixel format %s\n", attr); |
| return AVERROR_INVALIDDATA; |
| } |
| } else if (!strcmp(attr, "width")) { |
| /* This is an integer between 1 and 1048561 |
| * and MUST be in multiples of 16. */ |
| codec->width = atoi(value); |
| return 0; |
| } else if (!strcmp(attr, "height")) { |
| /* This is an integer between 1 and 1048561 |
| * and MUST be in multiples of 16. */ |
| codec->height = atoi(value); |
| return 0; |
| } else if (!strcmp(attr, "delivery-method")) { |
| /* Possible values are: inline, in_band, out_band/specific_name. */ |
| return AVERROR_PATCHWELCOME; |
| } else if (!strcmp(attr, "configuration-uri")) { |
| /* NOTE: configuration-uri is supported only under 2 conditions: |
| *--after the delivery-method tag |
| * --with a delivery-method value of out_band */ |
| return AVERROR_PATCHWELCOME; |
| } else if (!strcmp(attr, "configuration")) { |
| /* NOTE: configuration is supported only AFTER the delivery-method tag |
| * The configuration value is a base64 encoded packed header */ |
| uint8_t *decoded_packet = NULL; |
| int packet_size; |
| size_t decoded_alloc = strlen(value) / 4 * 3 + 4; |
| |
| if (decoded_alloc <= INT_MAX) { |
| decoded_packet = av_malloc(decoded_alloc); |
| if (decoded_packet) { |
| packet_size = |
| av_base64_decode(decoded_packet, value, decoded_alloc); |
| |
| result = parse_packed_headers |
| (decoded_packet, decoded_packet + packet_size, codec, |
| xiph_data); |
| } else { |
| av_log(codec, AV_LOG_ERROR, |
| "Out of memory while decoding SDP configuration.\n"); |
| result = AVERROR(ENOMEM); |
| } |
| } else { |
| av_log(codec, AV_LOG_ERROR, "Packet too large\n"); |
| result = AVERROR_INVALIDDATA; |
| } |
| av_free(decoded_packet); |
| } |
| return result; |
| } |
| |
| static int xiph_parse_sdp_line(AVFormatContext *s, int st_index, |
| PayloadContext *data, const char *line) |
| { |
| const char *p; |
| |
| if (av_strstart(line, "fmtp:", &p)) { |
| return ff_parse_fmtp(s->streams[st_index], data, p, |
| xiph_parse_fmtp_pair); |
| } |
| |
| return 0; |
| } |
| |
| RTPDynamicProtocolHandler ff_theora_dynamic_handler = { |
| .enc_name = "theora", |
| .codec_type = AVMEDIA_TYPE_VIDEO, |
| .codec_id = CODEC_ID_THEORA, |
| .parse_sdp_a_line = xiph_parse_sdp_line, |
| .alloc = xiph_new_context, |
| .free = xiph_free_context, |
| .parse_packet = xiph_handle_packet |
| }; |
| |
| RTPDynamicProtocolHandler ff_vorbis_dynamic_handler = { |
| .enc_name = "vorbis", |
| .codec_type = AVMEDIA_TYPE_AUDIO, |
| .codec_id = CODEC_ID_VORBIS, |
| .parse_sdp_a_line = xiph_parse_sdp_line, |
| .alloc = xiph_new_context, |
| .free = xiph_free_context, |
| .parse_packet = xiph_handle_packet |
| }; |
