1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/**
* 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
*/
#ifndef AVUTIL_ENCRYPTION_INFO_H
#define AVUTIL_ENCRYPTION_INFO_H
#include <stddef.h>
#include <stdint.h>
typedef struct AVSubsampleEncryptionInfo {
/** The number of bytes that are clear. */
unsigned int bytes_of_clear_data;
/**
* The number of bytes that are protected. If using pattern encryption,
* the pattern applies to only the protected bytes; if not using pattern
* encryption, all these bytes are encrypted.
*/
unsigned int bytes_of_protected_data;
} AVSubsampleEncryptionInfo;
/**
* This describes encryption info for a packet. This contains frame-specific
* info for how to decrypt the packet before passing it to the decoder.
*
* The size of this struct is not part of the public ABI.
*/
typedef struct AVEncryptionInfo {
/** The fourcc encryption scheme, in big-endian byte order. */
uint32_t scheme;
/**
* Only used for pattern encryption. This is the number of 16-byte blocks
* that are encrypted.
*/
uint32_t crypt_byte_block;
/**
* Only used for pattern encryption. This is the number of 16-byte blocks
* that are clear.
*/
uint32_t skip_byte_block;
/**
* The ID of the key used to encrypt the packet. This should always be
* 16 bytes long, but may be changed in the future.
*/
uint8_t *key_id;
uint32_t key_id_size;
/**
* The initialization vector. This may have been zero-filled to be the
* correct block size. This should always be 16 bytes long, but may be
* changed in the future.
*/
uint8_t *iv;
uint32_t iv_size;
/**
* An array of subsample encryption info specifying how parts of the sample
* are encrypted. If there are no subsamples, then the whole sample is
* encrypted.
*/
AVSubsampleEncryptionInfo *subsamples;
uint32_t subsample_count;
} AVEncryptionInfo;
/**
* This describes info used to initialize an encryption key system.
*
* The size of this struct is not part of the public ABI.
*/
typedef struct AVEncryptionInitInfo {
/**
* A unique identifier for the key system this is for, can be NULL if it
* is not known. This should always be 16 bytes, but may change in the
* future.
*/
uint8_t* system_id;
uint32_t system_id_size;
/**
* An array of key IDs this initialization data is for. All IDs are the
* same length. Can be NULL if there are no known key IDs.
*/
uint8_t** key_ids;
/** The number of key IDs. */
uint32_t num_key_ids;
/**
* The number of bytes in each key ID. This should always be 16, but may
* change in the future.
*/
uint32_t key_id_size;
/**
* Key-system specific initialization data. This data is copied directly
* from the file and the format depends on the specific key system. This
* can be NULL if there is no initialization data; in that case, there
* will be at least one key ID.
*/
uint8_t* data;
uint32_t data_size;
} AVEncryptionInitInfo;
/**
* Allocates an AVEncryptionInfo structure and sub-pointers to hold the given
* number of subsamples. This will allocate pointers for the key ID, IV,
* and subsample entries, set the size members, and zero-initialize the rest.
*
* @param subsample_count The number of subsamples.
* @param key_id_size The number of bytes in the key ID, should be 16.
* @param key_id_size The number of bytes in the IV, should be 16.
*
* @return The new AVEncryptionInfo structure, or NULL on error.
*/
AVEncryptionInfo *av_encryption_info_alloc(uint32_t subsample_count, uint32_t key_id_size, uint32_t iv_size);
/**
* Allocates an AVEncryptionInfo structure with a copy of the given data.
* @return The new AVEncryptionInfo structure, or NULL on error.
*/
AVEncryptionInfo *av_encryption_info_clone(const AVEncryptionInfo *info);
/**
* Frees the given encryption info object. This MUST NOT be used to free the
* side-data data pointer, that should use normal side-data methods.
*/
void av_encryption_info_free(AVEncryptionInfo *info);
/**
* Creates a copy of the AVEncryptionInfo that is contained in the given side
* data. The resulting object should be passed to av_encryption_info_free()
* when done.
*
* @return The new AVEncryptionInfo structure, or NULL on error.
*/
AVEncryptionInfo *av_encryption_info_get_side_data(const uint8_t *side_data, size_t side_data_size);
/**
* Allocates and initializes side data that holds a copy of the given encryption
* info. The resulting pointer should be either freed using av_free or given
* to av_packet_add_side_data().
*
* @return The new side-data pointer, or NULL.
*/
uint8_t *av_encryption_info_add_side_data(
const AVEncryptionInfo *info, size_t *side_data_size);
/**
* Allocates an AVEncryptionInitInfo structure and sub-pointers to hold the
* given sizes. This will allocate pointers and set all the fields.
*
* @return The new AVEncryptionInitInfo structure, or NULL on error.
*/
AVEncryptionInitInfo *av_encryption_init_info_alloc(
uint32_t system_id_size, uint32_t num_key_ids, uint32_t key_id_size, uint32_t data_size);
/**
* Frees the given encryption init info object. This MUST NOT be used to free
* the side-data data pointer, that should use normal side-data methods.
*/
void av_encryption_init_info_free(AVEncryptionInitInfo* info);
/**
* Creates a copy of the AVEncryptionInitInfo that is contained in the given
* side data. The resulting object should be passed to
* av_encryption_init_info_free() when done.
*
* @return The new AVEncryptionInitInfo structure, or NULL on error.
*/
AVEncryptionInitInfo *av_encryption_init_info_get_side_data(
const uint8_t* side_data, size_t side_data_size);
/**
* Allocates and initializes side data that holds a copy of the given encryption
* init info. The resulting pointer should be either freed using av_free or
* given to av_packet_add_side_data().
*
* @return The new side-data pointer, or NULL.
*/
uint8_t *av_encryption_init_info_add_side_data(
const AVEncryptionInitInfo *info, size_t *side_data_size);
#endif /* AVUTIL_ENCRYPTION_INFO_H */
|
