xmv: Add more sanity checks for parameters read from the bitstream
[libav.git] / libavformat / rtmppkt.h
1 /*
2 * RTMP packet utilities
3 * Copyright (c) 2009 Konstantin Shishkov
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #ifndef AVFORMAT_RTMPPKT_H
23 #define AVFORMAT_RTMPPKT_H
24
25 #include "libavcodec/bytestream.h"
26 #include "avformat.h"
27 #include "url.h"
28
29 /** maximum possible number of different RTMP channels */
30 #define RTMP_CHANNELS 65599
31
32 /**
33 * channels used to for RTMP packets with different purposes (i.e. data, network
34 * control, remote procedure calls, etc.)
35 */
36 enum RTMPChannel {
37 RTMP_NETWORK_CHANNEL = 2, ///< channel for network-related messages (bandwidth report, ping, etc)
38 RTMP_SYSTEM_CHANNEL, ///< channel for sending server control messages
39 RTMP_AUDIO_CHANNEL, ///< channel for audio data
40 RTMP_VIDEO_CHANNEL = 6, ///< channel for video data
41 RTMP_SOURCE_CHANNEL = 8, ///< channel for a/v invokes
42 };
43
44 /**
45 * known RTMP packet types
46 */
47 typedef enum RTMPPacketType {
48 RTMP_PT_CHUNK_SIZE = 1, ///< chunk size change
49 RTMP_PT_BYTES_READ = 3, ///< number of bytes read
50 RTMP_PT_PING, ///< ping
51 RTMP_PT_SERVER_BW, ///< server bandwidth
52 RTMP_PT_CLIENT_BW, ///< client bandwidth
53 RTMP_PT_AUDIO = 8, ///< audio packet
54 RTMP_PT_VIDEO, ///< video packet
55 RTMP_PT_FLEX_STREAM = 15, ///< Flex shared stream
56 RTMP_PT_FLEX_OBJECT, ///< Flex shared object
57 RTMP_PT_FLEX_MESSAGE, ///< Flex shared message
58 RTMP_PT_NOTIFY, ///< some notification
59 RTMP_PT_SHARED_OBJ, ///< shared object
60 RTMP_PT_INVOKE, ///< invoke some stream action
61 RTMP_PT_METADATA = 22, ///< FLV metadata
62 } RTMPPacketType;
63
64 /**
65 * possible RTMP packet header sizes
66 */
67 enum RTMPPacketSize {
68 RTMP_PS_TWELVEBYTES = 0, ///< packet has 12-byte header
69 RTMP_PS_EIGHTBYTES, ///< packet has 8-byte header
70 RTMP_PS_FOURBYTES, ///< packet has 4-byte header
71 RTMP_PS_ONEBYTE ///< packet is really a next chunk of a packet
72 };
73
74 /**
75 * structure for holding RTMP packets
76 */
77 typedef struct RTMPPacket {
78 int channel_id; ///< RTMP channel ID (nothing to do with audio/video channels though)
79 RTMPPacketType type; ///< packet payload type
80 uint32_t timestamp; ///< packet full timestamp
81 uint32_t ts_delta; ///< timestamp increment to the previous one in milliseconds (latter only for media packets)
82 uint32_t extra; ///< probably an additional channel ID used during streaming data
83 uint8_t *data; ///< packet payload
84 int size; ///< packet payload size
85 } RTMPPacket;
86
87 /**
88 * Create new RTMP packet with given attributes.
89 *
90 * @param pkt packet
91 * @param channel_id packet channel ID
92 * @param type packet type
93 * @param timestamp packet timestamp
94 * @param size packet size
95 * @return zero on success, negative value otherwise
96 */
97 int ff_rtmp_packet_create(RTMPPacket *pkt, int channel_id, RTMPPacketType type,
98 int timestamp, int size);
99
100 /**
101 * Free RTMP packet.
102 *
103 * @param pkt packet
104 */
105 void ff_rtmp_packet_destroy(RTMPPacket *pkt);
106
107 /**
108 * Read RTMP packet sent by the server.
109 *
110 * @param h reader context
111 * @param p packet
112 * @param chunk_size current chunk size
113 * @param prev_pkt previously read packet headers for all channels
114 * (may be needed for restoring incomplete packet header)
115 * @return number of bytes read on success, negative value otherwise
116 */
117 int ff_rtmp_packet_read(URLContext *h, RTMPPacket *p,
118 int chunk_size, RTMPPacket *prev_pkt);
119 /**
120 * Read internal RTMP packet sent by the server.
121 *
122 * @param h reader context
123 * @param p packet
124 * @param chunk_size current chunk size
125 * @param prev_pkt previously read packet headers for all channels
126 * (may be needed for restoring incomplete packet header)
127 * @param c the first byte already read
128 * @return number of bytes read on success, negative value otherwise
129 */
130 int ff_rtmp_packet_read_internal(URLContext *h, RTMPPacket *p, int chunk_size,
131 RTMPPacket *prev_pkt, uint8_t c);
132
133 /**
134 * Send RTMP packet to the server.
135 *
136 * @param h reader context
137 * @param p packet to send
138 * @param chunk_size current chunk size
139 * @param prev_pkt previously sent packet headers for all channels
140 * (may be used for packet header compressing)
141 * @return number of bytes written on success, negative value otherwise
142 */
143 int ff_rtmp_packet_write(URLContext *h, RTMPPacket *p,
144 int chunk_size, RTMPPacket *prev_pkt);
145
146 /**
147 * Print information and contents of RTMP packet.
148 *
149 * @param ctx output context
150 * @param p packet to dump
151 */
152 void ff_rtmp_packet_dump(void *ctx, RTMPPacket *p);
153
154 /**
155 * @name Functions used to work with the AMF format (which is also used in .flv)
156 * @see amf_* funcs in libavformat/flvdec.c
157 * @{
158 */
159
160 /**
161 * Calculate number of bytes taken by first AMF entry in data.
162 *
163 * @param data input data
164 * @param data_end input buffer end
165 * @return number of bytes used by first AMF entry
166 */
167 int ff_amf_tag_size(const uint8_t *data, const uint8_t *data_end);
168
169 /**
170 * Retrieve value of given AMF object field in string form.
171 *
172 * @param data AMF object data
173 * @param data_end input buffer end
174 * @param name name of field to retrieve
175 * @param dst buffer for storing result
176 * @param dst_size output buffer size
177 * @return 0 if search and retrieval succeeded, negative value otherwise
178 */
179 int ff_amf_get_field_value(const uint8_t *data, const uint8_t *data_end,
180 const uint8_t *name, uint8_t *dst, int dst_size);
181
182 /**
183 * Write boolean value in AMF format to buffer.
184 *
185 * @param dst pointer to the input buffer (will be modified)
186 * @param val value to write
187 */
188 void ff_amf_write_bool(uint8_t **dst, int val);
189
190 /**
191 * Write number in AMF format to buffer.
192 *
193 * @param dst pointer to the input buffer (will be modified)
194 * @param num value to write
195 */
196 void ff_amf_write_number(uint8_t **dst, double num);
197
198 /**
199 * Write string in AMF format to buffer.
200 *
201 * @param dst pointer to the input buffer (will be modified)
202 * @param str string to write
203 */
204 void ff_amf_write_string(uint8_t **dst, const char *str);
205
206 /**
207 * Write a string consisting of two parts in AMF format to a buffer.
208 *
209 * @param dst pointer to the input buffer (will be modified)
210 * @param str1 first string to write, may be null
211 * @param str2 second string to write, may be null
212 */
213 void ff_amf_write_string2(uint8_t **dst, const char *str1, const char *str2);
214
215 /**
216 * Write AMF NULL value to buffer.
217 *
218 * @param dst pointer to the input buffer (will be modified)
219 */
220 void ff_amf_write_null(uint8_t **dst);
221
222 /**
223 * Write marker for AMF object to buffer.
224 *
225 * @param dst pointer to the input buffer (will be modified)
226 */
227 void ff_amf_write_object_start(uint8_t **dst);
228
229 /**
230 * Write string used as field name in AMF object to buffer.
231 *
232 * @param dst pointer to the input buffer (will be modified)
233 * @param str string to write
234 */
235 void ff_amf_write_field_name(uint8_t **dst, const char *str);
236
237 /**
238 * Write marker for end of AMF object to buffer.
239 *
240 * @param dst pointer to the input buffer (will be modified)
241 */
242 void ff_amf_write_object_end(uint8_t **dst);
243
244 /**
245 * Read AMF boolean value.
246 *
247 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
248 *@param[out] val 0 or 1
249 *@return 0 on success or an AVERROR code on failure
250 */
251 int ff_amf_read_bool(GetByteContext *gbc, int *val);
252
253 /**
254 * Read AMF number value.
255 *
256 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
257 *@param[out] val read value
258 *@return 0 on success or an AVERROR code on failure
259 */
260 int ff_amf_read_number(GetByteContext *gbc, double *val);
261
262 /**
263 * Read AMF string value.
264 *
265 * Appends a trailing null byte to output string in order to
266 * ease later parsing.
267 *
268 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
269 *@param[out] str read string
270 *@param[in] strsize buffer size available to store the read string
271 *@param[out] length read string length
272 *@return 0 on success or an AVERROR code on failure
273 */
274 int ff_amf_read_string(GetByteContext *gbc, uint8_t *str,
275 int strsize, int *length);
276
277 /**
278 * Read AMF NULL value.
279 *
280 *@param[in,out] gbc GetByteContext initialized with AMF-formatted data
281 *@return 0 on success or an AVERROR code on failure
282 */
283 int ff_amf_read_null(GetByteContext *gbc);
284
285 /**
286 * Match AMF string with a NULL-terminated string.
287 *
288 * @return 0 if the strings do not match.
289 */
290
291 int ff_amf_match_string(const uint8_t *data, int size, const char *str);
292
293 /** @} */ // AMF funcs
294
295 #endif /* AVFORMAT_RTMPPKT_H */