FFmpeg 5.1.4
encryption_info.h
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1/**
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#ifndef AVUTIL_ENCRYPTION_INFO_H
20#define AVUTIL_ENCRYPTION_INFO_H
21
22#include <stddef.h>
23#include <stdint.h>
24
26 /** The number of bytes that are clear. */
27 unsigned int bytes_of_clear_data;
28
29 /**
30 * The number of bytes that are protected. If using pattern encryption,
31 * the pattern applies to only the protected bytes; if not using pattern
32 * encryption, all these bytes are encrypted.
33 */
36
37/**
38 * This describes encryption info for a packet. This contains frame-specific
39 * info for how to decrypt the packet before passing it to the decoder.
40 *
41 * The size of this struct is not part of the public ABI.
42 */
43typedef struct AVEncryptionInfo {
44 /** The fourcc encryption scheme, in big-endian byte order. */
45 uint32_t scheme;
46
47 /**
48 * Only used for pattern encryption. This is the number of 16-byte blocks
49 * that are encrypted.
50 */
52
53 /**
54 * Only used for pattern encryption. This is the number of 16-byte blocks
55 * that are clear.
56 */
58
59 /**
60 * The ID of the key used to encrypt the packet. This should always be
61 * 16 bytes long, but may be changed in the future.
62 */
63 uint8_t *key_id;
64 uint32_t key_id_size;
65
66 /**
67 * The initialization vector. This may have been zero-filled to be the
68 * correct block size. This should always be 16 bytes long, but may be
69 * changed in the future.
70 */
71 uint8_t *iv;
72 uint32_t iv_size;
73
74 /**
75 * An array of subsample encryption info specifying how parts of the sample
76 * are encrypted. If there are no subsamples, then the whole sample is
77 * encrypted.
78 */
82
83/**
84 * This describes info used to initialize an encryption key system.
85 *
86 * The size of this struct is not part of the public ABI.
87 */
88typedef struct AVEncryptionInitInfo {
89 /**
90 * A unique identifier for the key system this is for, can be NULL if it
91 * is not known. This should always be 16 bytes, but may change in the
92 * future.
93 */
94 uint8_t* system_id;
96
97 /**
98 * An array of key IDs this initialization data is for. All IDs are the
99 * same length. Can be NULL if there are no known key IDs.
100 */
101 uint8_t** key_ids;
102 /** The number of key IDs. */
103 uint32_t num_key_ids;
104 /**
105 * The number of bytes in each key ID. This should always be 16, but may
106 * change in the future.
107 */
108 uint32_t key_id_size;
109
110 /**
111 * Key-system specific initialization data. This data is copied directly
112 * from the file and the format depends on the specific key system. This
113 * can be NULL if there is no initialization data; in that case, there
114 * will be at least one key ID.
115 */
116 uint8_t* data;
117 uint32_t data_size;
118
119 /**
120 * An optional pointer to the next initialization info in the list.
121 */
124
125/**
126 * Allocates an AVEncryptionInfo structure and sub-pointers to hold the given
127 * number of subsamples. This will allocate pointers for the key ID, IV,
128 * and subsample entries, set the size members, and zero-initialize the rest.
129 *
130 * @param subsample_count The number of subsamples.
131 * @param key_id_size The number of bytes in the key ID, should be 16.
132 * @param iv_size The number of bytes in the IV, should be 16.
133 *
134 * @return The new AVEncryptionInfo structure, or NULL on error.
135 */
136AVEncryptionInfo *av_encryption_info_alloc(uint32_t subsample_count, uint32_t key_id_size, uint32_t iv_size);
137
138/**
139 * Allocates an AVEncryptionInfo structure with a copy of the given data.
140 * @return The new AVEncryptionInfo structure, or NULL on error.
141 */
143
144/**
145 * Frees the given encryption info object. This MUST NOT be used to free the
146 * side-data data pointer, that should use normal side-data methods.
147 */
149
150/**
151 * Creates a copy of the AVEncryptionInfo that is contained in the given side
152 * data. The resulting object should be passed to av_encryption_info_free()
153 * when done.
154 *
155 * @return The new AVEncryptionInfo structure, or NULL on error.
156 */
157AVEncryptionInfo *av_encryption_info_get_side_data(const uint8_t *side_data, size_t side_data_size);
158
159/**
160 * Allocates and initializes side data that holds a copy of the given encryption
161 * info. The resulting pointer should be either freed using av_free or given
162 * to av_packet_add_side_data().
163 *
164 * @return The new side-data pointer, or NULL.
165 */
167 const AVEncryptionInfo *info, size_t *side_data_size);
168
169
170/**
171 * Allocates an AVEncryptionInitInfo structure and sub-pointers to hold the
172 * given sizes. This will allocate pointers and set all the fields.
173 *
174 * @return The new AVEncryptionInitInfo structure, or NULL on error.
175 */
177 uint32_t system_id_size, uint32_t num_key_ids, uint32_t key_id_size, uint32_t data_size);
178
179/**
180 * Frees the given encryption init info object. This MUST NOT be used to free
181 * the side-data data pointer, that should use normal side-data methods.
182 */
184
185/**
186 * Creates a copy of the AVEncryptionInitInfo that is contained in the given
187 * side data. The resulting object should be passed to
188 * av_encryption_init_info_free() when done.
189 *
190 * @return The new AVEncryptionInitInfo structure, or NULL on error.
191 */
193 const uint8_t* side_data, size_t side_data_size);
194
195/**
196 * Allocates and initializes side data that holds a copy of the given encryption
197 * init info. The resulting pointer should be either freed using av_free or
198 * given to av_packet_add_side_data().
199 *
200 * @return The new side-data pointer, or NULL.
201 */
203 const AVEncryptionInitInfo *info, size_t *side_data_size);
204
205#endif /* AVUTIL_ENCRYPTION_INFO_H */
AVEncryptionInfo * av_encryption_info_alloc(uint32_t subsample_count, uint32_t key_id_size, uint32_t iv_size)
Allocates an AVEncryptionInfo structure and sub-pointers to hold the given number of subsamples.
AVEncryptionInfo * av_encryption_info_clone(const AVEncryptionInfo *info)
Allocates an AVEncryptionInfo structure with a copy of the given data.
AVEncryptionInitInfo * av_encryption_init_info_get_side_data(const uint8_t *side_data, size_t side_data_size)
Creates a copy of the AVEncryptionInitInfo that is contained in the given side data.
uint8_t * av_encryption_init_info_add_side_data(const AVEncryptionInitInfo *info, size_t *side_data_size)
Allocates and initializes side data that holds a copy of the given encryption init info.
uint8_t * av_encryption_info_add_side_data(const AVEncryptionInfo *info, size_t *side_data_size)
Allocates and initializes side data that holds a copy of the given encryption info.
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)
Allocates an AVEncryptionInitInfo structure and sub-pointers to hold the given sizes.
void av_encryption_init_info_free(AVEncryptionInitInfo *info)
Frees the given encryption init info object.
AVEncryptionInfo * av_encryption_info_get_side_data(const uint8_t *side_data, size_t side_data_size)
Creates a copy of the AVEncryptionInfo that is contained in the given side data.
void av_encryption_info_free(AVEncryptionInfo *info)
Frees the given encryption info object.
This describes encryption info for a packet.
uint32_t skip_byte_block
Only used for pattern encryption.
uint8_t * iv
The initialization vector.
uint32_t crypt_byte_block
Only used for pattern encryption.
uint8_t * key_id
The ID of the key used to encrypt the packet.
uint32_t subsample_count
AVSubsampleEncryptionInfo * subsamples
An array of subsample encryption info specifying how parts of the sample are encrypted.
uint32_t scheme
The fourcc encryption scheme, in big-endian byte order.
This describes info used to initialize an encryption key system.
uint8_t * data
Key-system specific initialization data.
struct AVEncryptionInitInfo * next
An optional pointer to the next initialization info in the list.
uint8_t ** key_ids
An array of key IDs this initialization data is for.
uint8_t * system_id
A unique identifier for the key system this is for, can be NULL if it is not known.
uint32_t key_id_size
The number of bytes in each key ID.
uint32_t num_key_ids
The number of key IDs.
This file is part of FFmpeg.
unsigned int bytes_of_clear_data
The number of bytes that are clear.
unsigned int bytes_of_protected_data
The number of bytes that are protected.