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1 /* | |
2 * Microsoft RTP/ASF support. | |
3 * Copyright (c) 2008 Ronald S. Bultje | |
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 libavformat/rtp_asf.c | |
24 * @brief Microsoft RTP/ASF support | |
25 * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net> | |
26 */ | |
27 | |
28 #include <libavutil/base64.h> | |
29 #include <libavutil/avstring.h> | |
30 #include <libavutil/intreadwrite.h> | |
31 #include "rtp.h" | |
32 #include "rtp_asf.h" | |
33 #include "rtsp.h" | |
34 #include "asf.h" | |
35 | |
36 /** | |
37 * From MSDN 2.2.1.4, we learn that ASF data packets over RTP should not | |
38 * contain any padding. Unfortunately, the header min/max_pktsize are not | |
39 * updated (thus making min_pktsize invalid). Here, we "fix" these faulty | |
40 * min_pktsize values in the ASF file header. | |
41 * @return 0 on success, <0 on failure (currently -1). | |
42 */ | |
43 static int rtp_asf_fix_header(uint8_t *buf, int len) | |
44 { | |
45 uint8_t *p = buf, *end = buf + len; | |
46 | |
47 if (len < sizeof(ff_asf_guid) * 2 + 22 || | |
48 memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) { | |
49 return -1; | |
50 } | |
51 p += sizeof(ff_asf_guid) + 14; | |
52 do { | |
53 uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid)); | |
54 if (memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) { | |
55 if (chunksize > end - p) | |
56 return -1; | |
57 p += chunksize; | |
58 continue; | |
59 } | |
60 | |
61 /* skip most of the file header, to min_pktsize */ | |
62 p += 6 * 8 + 3 * 4 + sizeof(ff_asf_guid) * 2; | |
63 if (p + 8 <= end && AV_RL32(p) == AV_RL32(p + 4)) { | |
64 /* and set that to zero */ | |
65 AV_WL32(p, 0); | |
66 return 0; | |
67 } | |
68 break; | |
69 } while (end - p >= sizeof(ff_asf_guid) + 8); | |
70 | |
71 return -1; | |
72 } | |
73 | |
74 /** | |
75 * The following code is basically a buffered ByteIOContext, | |
76 * with the added benefit of returning -EAGAIN (instead of 0) | |
77 * on packet boundaries, such that the ASF demuxer can return | |
78 * safely and resume business at the next packet. | |
79 */ | |
80 static int packetizer_read(void *opaque, uint8_t *buf, int buf_size) | |
81 { | |
82 return AVERROR(EAGAIN); | |
83 } | |
84 | |
85 static void init_packetizer(ByteIOContext *pb, uint8_t *buf, int len) | |
86 { | |
87 init_put_byte(pb, buf, len, 0, NULL, packetizer_read, NULL, NULL); | |
88 | |
89 /* this "fills" the buffer with its current content */ | |
90 pb->pos = len; | |
91 pb->buf_end = buf + len; | |
92 } | |
93 | |
94 void ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p) | |
95 { | |
96 if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p
)) { | |
97 ByteIOContext pb; | |
98 RTSPState *rt = s->priv_data; | |
99 int len = strlen(p) * 6 / 8; | |
100 char *buf = av_mallocz(len); | |
101 av_base64_decode(buf, p, len); | |
102 | |
103 if (rtp_asf_fix_header(buf, len) < 0) | |
104 av_log(s, AV_LOG_ERROR, | |
105 "Failed to fix invalid RTSP-MS/ASF min_pktsize\n"); | |
106 init_packetizer(&pb, buf, len); | |
107 if (rt->asf_ctx) { | |
108 av_close_input_stream(rt->asf_ctx); | |
109 rt->asf_ctx = NULL; | |
110 } | |
111 av_open_input_stream(&rt->asf_ctx, &pb, "", &asf_demuxer, NULL); | |
112 rt->asf_pb_pos = url_ftell(&pb); | |
113 av_free(buf); | |
114 rt->asf_ctx->pb = NULL; | |
115 } | |
116 } | |
117 | |
118 static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index, | |
119 PayloadContext *asf, const char *line) | |
120 { | |
121 if (av_strstart(line, "stream:", &line)) { | |
122 RTSPState *rt = s->priv_data; | |
123 | |
124 s->streams[stream_index]->id = strtol(line, NULL, 10); | |
125 | |
126 if (rt->asf_ctx) { | |
127 int i; | |
128 | |
129 for (i = 0; i < rt->asf_ctx->nb_streams; i++) { | |
130 if (s->streams[stream_index]->id == rt->asf_ctx->streams[i]->id)
{ | |
131 *s->streams[stream_index]->codec = | |
132 *rt->asf_ctx->streams[i]->codec; | |
133 rt->asf_ctx->streams[i]->codec->extradata_size = 0; | |
134 rt->asf_ctx->streams[i]->codec->extradata = NULL; | |
135 av_set_pts_info(s->streams[stream_index], 32, 1, 1000); | |
136 } | |
137 } | |
138 } | |
139 } | |
140 | |
141 return 0; | |
142 } | |
143 | |
144 struct PayloadContext { | |
145 ByteIOContext *pktbuf, pb; | |
146 char *buf; | |
147 }; | |
148 | |
149 /** | |
150 * @return 0 when a packet was written into /p pkt, and no more data is left; | |
151 * 1 when a packet was written into /p pkt, and more packets might be le
ft; | |
152 * <0 when not enough data was provided to return a full packet, or on er
ror. | |
153 */ | |
154 static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf, | |
155 AVStream *st, AVPacket *pkt, | |
156 uint32_t *timestamp, | |
157 const uint8_t *buf, int len, int flags) | |
158 { | |
159 ByteIOContext *pb = &asf->pb; | |
160 int res, mflags, len_off; | |
161 RTSPState *rt = s->priv_data; | |
162 | |
163 if (!rt->asf_ctx) | |
164 return -1; | |
165 | |
166 if (len > 0) { | |
167 int off, out_len; | |
168 | |
169 if (len < 4) | |
170 return -1; | |
171 | |
172 init_put_byte(pb, buf, len, 0, NULL, NULL, NULL, NULL); | |
173 mflags = get_byte(pb); | |
174 if (mflags & 0x80) | |
175 flags |= RTP_FLAG_KEY; | |
176 len_off = get_be24(pb); | |
177 if (mflags & 0x20) /**< relative timestamp */ | |
178 url_fskip(pb, 4); | |
179 if (mflags & 0x10) /**< has duration */ | |
180 url_fskip(pb, 4); | |
181 if (mflags & 0x8) /**< has location ID */ | |
182 url_fskip(pb, 4); | |
183 off = url_ftell(pb); | |
184 | |
185 av_freep(&asf->buf); | |
186 if (!(mflags & 0x40)) { | |
187 /** | |
188 * If 0x40 is not set, the len_off field specifies an offset of this | |
189 * packet's payload data in the complete (reassembled) ASF packet. | |
190 * This is used to spread one ASF packet over multiple RTP packets. | |
191 */ | |
192 if (asf->pktbuf && len_off != url_ftell(asf->pktbuf)) { | |
193 uint8_t *p; | |
194 url_close_dyn_buf(asf->pktbuf, &p); | |
195 asf->pktbuf = NULL; | |
196 av_free(p); | |
197 } | |
198 if (!len_off && !asf->pktbuf && | |
199 !(res = url_open_dyn_packet_buf(&asf->pktbuf, rt->asf_ctx->packe
t_size))) | |
200 return res; | |
201 if (!asf->pktbuf) | |
202 return AVERROR(EIO); | |
203 | |
204 put_buffer(asf->pktbuf, buf + off, len - off); | |
205 if (!(flags & RTP_FLAG_MARKER)) | |
206 return -1; | |
207 out_len = url_close_dyn_buf(asf->pktbuf, &asf->buf); | |
208 asf->pktbuf = NULL; | |
209 } else { | |
210 /** | |
211 * If 0x40 is set, the len_off field specifies the length of the | |
212 * next ASF packet that can be read from this payload data alone. | |
213 * This is commonly the same as the payload size, but could be | |
214 * less in case of packet splitting (i.e. multiple ASF packets in | |
215 * one RTP packet). | |
216 */ | |
217 if (len_off != len) { | |
218 av_log_missing_feature(s, | |
219 "RTSP-MS packet splitting", 1); | |
220 return -1; | |
221 } | |
222 asf->buf = av_malloc(len - off); | |
223 out_len = len - off; | |
224 memcpy(asf->buf, buf + off, len - off); | |
225 } | |
226 | |
227 init_packetizer(pb, asf->buf, out_len); | |
228 pb->pos += rt->asf_pb_pos; | |
229 pb->eof_reached = 0; | |
230 rt->asf_ctx->pb = pb; | |
231 } | |
232 | |
233 for (;;) { | |
234 int i; | |
235 | |
236 res = av_read_packet(rt->asf_ctx, pkt); | |
237 rt->asf_pb_pos = url_ftell(pb); | |
238 if (res != 0) | |
239 break; | |
240 for (i = 0; i < s->nb_streams; i++) { | |
241 if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id
) { | |
242 pkt->stream_index = i; | |
243 return 1; // FIXME: return 0 if last packet | |
244 } | |
245 } | |
246 av_free_packet(pkt); | |
247 } | |
248 | |
249 return res == 1 ? -1 : res; | |
250 } | |
251 | |
252 static PayloadContext *asfrtp_new_context(void) | |
253 { | |
254 return av_mallocz(sizeof(PayloadContext)); | |
255 } | |
256 | |
257 static void asfrtp_free_context(PayloadContext *asf) | |
258 { | |
259 if (asf->pktbuf) { | |
260 uint8_t *p = NULL; | |
261 url_close_dyn_buf(asf->pktbuf, &p); | |
262 asf->pktbuf = NULL; | |
263 av_free(p); | |
264 } | |
265 av_freep(&asf->buf); | |
266 av_free(asf); | |
267 } | |
268 | |
269 #define RTP_ASF_HANDLER(n, s, t) \ | |
270 RTPDynamicProtocolHandler ff_ms_rtp_ ## n ## _handler = { \ | |
271 .enc_name = s, \ | |
272 .codec_type = t, \ | |
273 .codec_id = CODEC_ID_NONE, \ | |
274 .parse_sdp_a_line = asfrtp_parse_sdp_line, \ | |
275 .open = asfrtp_new_context, \ | |
276 .close = asfrtp_free_context, \ | |
277 .parse_packet = asfrtp_parse_packet, \ | |
278 }; | |
279 | |
280 RTP_ASF_HANDLER(asf_pfv, "x-asf-pf", CODEC_TYPE_VIDEO); | |
281 RTP_ASF_HANDLER(asf_pfa, "x-asf-pf", CODEC_TYPE_AUDIO); | |
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