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
|
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION)
#error "Never include this file directly, include libavb.h instead."
#endif
#ifndef AVB_OPS_H_
#define AVB_OPS_H_
#include "avb_sysdeps.h"
#ifdef __cplusplus
extern "C" {
#endif
/* Return codes used for I/O operations.
*
* AVB_IO_RESULT_OK is returned if the requested operation was
* successful.
*
* AVB_IO_RESULT_ERROR_IO is returned if the underlying hardware (disk
* or other subsystem) encountered an I/O error.
*
* AVB_IO_RESULT_ERROR_OOM is returned if unable to allocate memory.
*
* AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION is returned if the requested
* partition does not exist.
*
* AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION is returned if the
* range of bytes requested to be read or written is outside the range
* of the partition.
*/
typedef enum {
AVB_IO_RESULT_OK,
AVB_IO_RESULT_ERROR_OOM,
AVB_IO_RESULT_ERROR_IO,
AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION,
AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION
} AvbIOResult;
struct AvbOps;
typedef struct AvbOps AvbOps;
struct AvbABData;
/* High-level operations/functions/methods that are platform
* dependent.
*/
struct AvbOps {
/* Reads |num_bytes| from offset |offset| from partition with name
* |partition| (NUL-terminated UTF-8 string). If |offset| is
* negative, its absolute value should be interpreted as the number
* of bytes from the end of the partition.
*
* This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if
* there is no partition with the given name,
* AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested
* |offset| is outside the partition, and AVB_IO_RESULT_ERROR_IO if
* there was an I/O error from the underlying I/O subsystem. If the
* operation succeeds as requested AVB_IO_RESULT_OK is returned and
* the data is available in |buffer|.
*
* The only time partial I/O may occur is if reading beyond the end
* of the partition. In this case the value returned in
* |out_num_read| may be smaller than |num_bytes|.
*/
AvbIOResult (*read_from_partition)(AvbOps* ops, const char* partition,
int64_t offset, size_t num_bytes,
void* buffer, size_t* out_num_read);
/* Writes |num_bytes| from |bffer| at offset |offset| to partition
* with name |partition| (NUL-terminated UTF-8 string). If |offset|
* is negative, its absolute value should be interpreted as the
* number of bytes from the end of the partition.
*
* This function returns AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION if
* there is no partition with the given name,
* AVB_IO_RESULT_ERROR_RANGE_OUTSIDE_PARTITION if the requested
* byterange goes outside the partition, and AVB_IO_RESULT_ERROR_IO
* if there was an I/O error from the underlying I/O subsystem. If
* the operation succeeds as requested AVB_IO_RESULT_OK is
* returned.
*
* This function never does any partial I/O, it either transfers all
* of the requested bytes or returns an error.
*/
AvbIOResult (*write_to_partition)(AvbOps* ops, const char* partition,
int64_t offset, size_t num_bytes,
const void* buffer);
/* Checks if the given public key used to sign the 'vbmeta'
* partition is trusted. Boot loaders typically compare this with
* embedded key material generated with 'avbtool
* extract_public_key'.
*
* If AVB_IO_RESULT_OK is returned then |out_is_trusted| is set -
* true if trusted or false if untrusted.
*/
AvbIOResult (*validate_vbmeta_public_key)(AvbOps* ops,
const uint8_t* public_key_data,
size_t public_key_length,
bool* out_is_trusted);
/* Gets the rollback index corresponding to the slot given by
* |rollback_index_slot|. The value is returned in
* |out_rollback_index|. Returns AVB_IO_RESULT_OK if the rollback
* index was retrieved, otherwise an error code.
*
* A device may have a limited amount of rollback index slots (say,
* one or four) so may error out if |rollback_index_slot| exceeds
* this number.
*/
AvbIOResult (*read_rollback_index)(AvbOps* ops, size_t rollback_index_slot,
uint64_t* out_rollback_index);
/* Sets the rollback index corresponding to the slot given by
* |rollback_index_slot| to |rollback_index|. Returns
* AVB_IO_RESULT_OK if the rollback index was set, otherwise an
* error code.
*
* A device may have a limited amount of rollback index slots (say,
* one or four) so may error out if |rollback_index_slot| exceeds
* this number.
*/
AvbIOResult (*write_rollback_index)(AvbOps* ops, size_t rollback_index_slot,
uint64_t rollback_index);
/* Gets whether the device is unlocked. The value is returned in
* |out_is_unlocked| (true if unlocked, false otherwise). Returns
* AVB_IO_RESULT_OK if the state was retrieved, otherwise an error
* code.
*/
AvbIOResult (*read_is_device_unlocked)(AvbOps* ops, bool* out_is_unlocked);
/* Gets the unique partition GUID for a partition with name in
* |partition| (NUL-terminated UTF-8 string). The GUID is copied as
* a string into |guid_buf| of size |guid_buf_size| and will be NUL
* terminated. The string must be lower-case and properly
* hyphenated. For example:
*
* 527c1c6d-6361-4593-8842-3c78fcd39219
*
* Returns AVB_IO_RESULT_OK on success, otherwise an error code.
*/
AvbIOResult (*get_unique_guid_for_partition)(AvbOps* ops,
const char* partition,
char* guid_buf,
size_t guid_buf_size);
};
#ifdef __cplusplus
}
#endif
#endif /* AVB_OPS_H_ */
|
