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David Zeuthen21e95262016-07-27 17:58:40 -04001/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
David Zeuthenc612e2e2016-09-16 16:44:08 -04004 * Permission is hereby granted, free of charge, to any person
5 * obtaining a copy of this software and associated documentation
6 * files (the "Software"), to deal in the Software without
7 * restriction, including without limitation the rights to use, copy,
8 * modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
David Zeuthen21e95262016-07-27 17:58:40 -040011 *
David Zeuthenc612e2e2016-09-16 16:44:08 -040012 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
David Zeuthen21e95262016-07-27 17:58:40 -040014 *
David Zeuthenc612e2e2016-09-16 16:44:08 -040015 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
David Zeuthen21e95262016-07-27 17:58:40 -040023 */
24
25#if !defined(AVB_INSIDE_LIBAVB_H) && !defined(AVB_COMPILATION)
26#error "Never include this file directly, include libavb.h instead."
27#endif
28
29#ifndef AVB_SLOT_VERIFY_H_
30#define AVB_SLOT_VERIFY_H_
31
32#include "avb_ops.h"
33#include "avb_vbmeta_image.h"
34
35#ifdef __cplusplus
36extern "C" {
37#endif
38
39/* Return codes used in avb_slot_verify(), see that function for
40 * documentation for each field.
David Zeuthen8b6973b2016-09-20 12:39:49 -040041 *
42 * Use avb_slot_verify_result_to_string() to get a textual
43 * representation usable for error/debug output.
David Zeuthen21e95262016-07-27 17:58:40 -040044 */
45typedef enum {
46 AVB_SLOT_VERIFY_RESULT_OK,
47 AVB_SLOT_VERIFY_RESULT_ERROR_OOM,
48 AVB_SLOT_VERIFY_RESULT_ERROR_IO,
49 AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION,
50 AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX,
51 AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED,
David Zeuthene3cadca2017-02-22 21:25:46 -050052 AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA,
53 AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION
David Zeuthen21e95262016-07-27 17:58:40 -040054} AvbSlotVerifyResult;
55
David Zeuthen8b6973b2016-09-20 12:39:49 -040056/* Get a textual representation of |result|. */
57const char* avb_slot_verify_result_to_string(AvbSlotVerifyResult result);
58
David Zeuthenbaf59e22016-11-14 15:39:43 -050059/* Maximum number of rollback index locations supported. */
David Zeuthen40ee1da2016-11-23 15:14:49 -050060#define AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_LOCATIONS 32
David Zeuthen21e95262016-07-27 17:58:40 -040061
David Zeuthena8bb9a02016-10-28 14:36:55 -040062/* AvbPartitionData contains data loaded from partitions when using
63 * avb_slot_verify(). The |partition_name| field contains the name of
David Zeuthen8681a332016-11-23 13:44:06 -050064 * the partition (without A/B suffix), |data| points to the loaded
65 * data which is |data_size| bytes long.
David Zeuthena8bb9a02016-10-28 14:36:55 -040066 *
67 * Note that this is strictly less than the partition size - it's only
68 * the image stored there, not the entire partition nor any of the
69 * metadata.
70 */
71typedef struct {
72 char* partition_name;
73 uint8_t* data;
74 size_t data_size;
75} AvbPartitionData;
76
David Zeuthen8681a332016-11-23 13:44:06 -050077/* AvbVBMetaData contains a vbmeta struct loaded from a partition when
78 * using avb_slot_verify(). The |partition_name| field contains the
79 * name of the partition (without A/B suffix), |vbmeta_data| points to
80 * the loaded data which is |vbmeta_size| bytes long.
81 *
82 * The |verify_result| field contains the result of
83 * avb_vbmeta_image_verify() on the data. This is guaranteed to be
84 * AVB_VBMETA_VERIFY_RESULT_OK for all vbmeta images if
85 * avb_slot_verify() returns AVB_SLOT_VERIFY_RESULT_OK.
86 *
87 * You can use avb_descriptor_get_all(), avb_descriptor_foreach(), and
88 * avb_vbmeta_image_header_to_host_byte_order() with this data.
89 */
90typedef struct {
91 char* partition_name;
92 uint8_t* vbmeta_data;
93 size_t vbmeta_size;
94 AvbVBMetaVerifyResult verify_result;
95} AvbVBMetaData;
96
David Zeuthen21e95262016-07-27 17:58:40 -040097/* AvbSlotVerifyData contains data needed to boot a particular slot
98 * and is returned by avb_slot_verify() if partitions in a slot are
99 * successfully verified.
100 *
David Zeuthena8bb9a02016-10-28 14:36:55 -0400101 * All data pointed to by this struct - including data in each item in
102 * the |partitions| array - will be freed when the
David Zeuthen21e95262016-07-27 17:58:40 -0400103 * avb_slot_verify_data_free() function is called.
104 *
David Zeuthen8b6973b2016-09-20 12:39:49 -0400105 * The |ab_suffix| field is the copy of the of |ab_suffix| field
106 * passed to avb_slot_verify(). It is the A/B suffix of the slot.
107 *
David Zeuthen8681a332016-11-23 13:44:06 -0500108 * The VBMeta images that were checked are available in the
109 * |vbmeta_images| field. The field |num_vbmeta_images| contains the
110 * number of elements in this array. The first element -
David Zeuthena5fd3a42017-02-27 16:38:54 -0500111 * vbmeta_images[0] - is guaranteed to be from the partition with the
112 * top-level vbmeta struct. This is usually the "vbmeta" partition in
113 * the requested slot but if there is no "vbmeta" partition it can
114 * also be the "boot" partition.
David Zeuthen8681a332016-11-23 13:44:06 -0500115 *
David Zeuthena8bb9a02016-10-28 14:36:55 -0400116 * The partitions loaded and verified from from the slot are
117 * accessible in the |loaded_partitions| array. The field
118 * |num_loaded_partitions| contains the number of elements in this
119 * array. The order of partitions in this array may not necessarily be
120 * the same order as in the passed-in |requested_partitions| array.
David Zeuthen21e95262016-07-27 17:58:40 -0400121 *
David Zeuthenbaf59e22016-11-14 15:39:43 -0500122 * Rollback indexes for the verified slot are stored in the
123 * |rollback_indexes| field. Note that avb_slot_verify() will NEVER
124 * modify stored_rollback_index[n] locations e.g. it will never use
125 * the write_rollback_index() AvbOps operation. Instead it is the job
126 * of the caller of avb_slot_verify() to do this based on e.g. A/B
127 * policy and other factors. See libavb_ab/avb_ab_flow.c for an
128 * example of how to do this.
David Zeuthen21e95262016-07-27 17:58:40 -0400129 *
130 * The |cmdline| field is a NUL-terminated string in UTF-8 resulting
131 * from concatenating all |AvbKernelCmdlineDescriptor| and then
132 * performing proper substitution of the variables
David Zeuthen57ac06e2017-01-10 13:06:14 -0500133 * $(ANDROID_SYSTEM_PARTUUID), $(ANDROID_BOOT_PARTUUID), and
134 * $(ANDROID_VBMETA_PARTUUID) using the
David Zeuthen21e95262016-07-27 17:58:40 -0400135 * get_unique_guid_for_partition() operation in |AvbOps|.
136 *
137 * Additionally, the |cmdline| field will have the following kernel
138 * command-line options set:
139 *
David Zeuthen8681a332016-11-23 13:44:06 -0500140 * androidboot.vbmeta.device_state: set to "locked" or "unlocked"
David Zeuthen21e95262016-07-27 17:58:40 -0400141 * depending on the result of the result of AvbOps's
142 * read_is_unlocked() function.
143 *
David Zeuthen21e95262016-07-27 17:58:40 -0400144 * androidboot.vbmeta.{hash_alg, size, digest}: Will be set to
David Zeuthen8681a332016-11-23 13:44:06 -0500145 * the digest of all images in |vbmeta_images|.
David Zeuthena8bb9a02016-10-28 14:36:55 -0400146 *
David Zeuthen57ac06e2017-01-10 13:06:14 -0500147 * androidboot.vbmeta.device: This is set to the value
148 * PARTUUID=$(ANDROID_VBMETA_PARTUUID) before substitution so it
149 * will end up pointing to the vbmeta partition for the verified
David Zeuthena5fd3a42017-02-27 16:38:54 -0500150 * slot. If there is no vbmeta partition it will point to the boot
151 * partition of the verified slot.
David Zeuthen57ac06e2017-01-10 13:06:14 -0500152 *
David Zeuthene3cadca2017-02-22 21:25:46 -0500153 * androidboot.vbmeta.avb_version: This is set to the decimal value
154 * of AVB_VERSION_MAJOR followed by a dot followed by the decimal
155 * value of AVB_VERSION_MINOR, for example "1.0" or "1.4". This
156 * version number represents the vbmeta file format version
157 * supported by libavb copy used in the boot loader. This is not
158 * necessarily the same version number of the on-disk metadata for
159 * the slot that was verified.
David Zeuthenbc41cea2017-02-16 14:07:11 -0500160 *
David Zeuthen19c38432017-02-16 13:08:38 -0500161 * Note that androidboot.slot_suffix is not set in |cmdline| - you
David Zeuthenbc41cea2017-02-16 14:07:11 -0500162 * will have to pass this command-line option yourself.
David Zeuthen19c38432017-02-16 13:08:38 -0500163 *
David Zeuthena8bb9a02016-10-28 14:36:55 -0400164 * This struct may grow in the future without it being considered an
165 * ABI break.
David Zeuthen21e95262016-07-27 17:58:40 -0400166 */
167typedef struct {
David Zeuthen8b6973b2016-09-20 12:39:49 -0400168 char* ab_suffix;
David Zeuthen8681a332016-11-23 13:44:06 -0500169 AvbVBMetaData* vbmeta_images;
170 size_t num_vbmeta_images;
David Zeuthena8bb9a02016-10-28 14:36:55 -0400171 AvbPartitionData* loaded_partitions;
172 size_t num_loaded_partitions;
David Zeuthen21e95262016-07-27 17:58:40 -0400173 char* cmdline;
David Zeuthen40ee1da2016-11-23 15:14:49 -0500174 uint64_t rollback_indexes[AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_LOCATIONS];
David Zeuthen21e95262016-07-27 17:58:40 -0400175} AvbSlotVerifyData;
176
177/* Frees a |AvbSlotVerifyData| including all data it points to. */
178void avb_slot_verify_data_free(AvbSlotVerifyData* data);
179
David Zeuthena8bb9a02016-10-28 14:36:55 -0400180/* Performs a full verification of the slot identified by |ab_suffix|
181 * and load the contents of the partitions whose name is in the
182 * NULL-terminated string array |requested_partitions| (each partition
183 * must use hash verification). If not using A/B, pass an empty string
184 * (e.g. "", not NULL) for |ab_suffix|.
David Zeuthen21e95262016-07-27 17:58:40 -0400185 *
David Zeuthena8bb9a02016-10-28 14:36:55 -0400186 * Typically the |requested_partitions| array only contains a single
187 * item for the boot partition, 'boot'.
188 *
189 * Verification includes loading data from the 'vbmeta', all hash
190 * partitions, and possibly other partitions (with |ab_suffix|
191 * appended), inspecting rollback indexes, and checking if the public
192 * key used to sign the data is acceptable. The functions in |ops|
193 * will be used to do this.
David Zeuthen21e95262016-07-27 17:58:40 -0400194 *
195 * If |out_data| is not NULL, it will be set to a newly allocated
196 * |AvbSlotVerifyData| struct containing all the data needed to
197 * actually boot the slot. This data structure should be freed with
David Zeuthen0155e6b2016-11-16 17:58:13 -0500198 * avb_slot_verify_data_free() when you are done with it. See below
199 * for when this is returned.
200 *
201 * If |allow_verification_error| is false this function will bail out
202 * as soon as an error is encountered and |out_data| is set only if
203 * AVB_SLOT_VERIFY_RESULT_OK is returned.
204 *
205 * Otherwise if |allow_verification_error| is true the function will
206 * continue verification efforts and |out_data| is also set if
207 * AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED,
208 * AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION, or
209 * AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX is returned. It is
210 * undefined which error is returned if more than one distinct error
211 * is encountered. It is guaranteed that AVB_SLOT_VERIFY_RESULT_OK is
212 * returned if, and only if, there are no errors. This mode is needed
213 * to boot valid but unverified slots when the device is unlocked.
214 *
215 * Also note that |out_data| is never set if
216 * AVB_SLOT_VERIFY_RESULT_ERROR_OOM, AVB_SLOT_VERIFY_RESULT_ERROR_IO,
217 * or AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA is returned.
David Zeuthen21e95262016-07-27 17:58:40 -0400218 *
219 * AVB_SLOT_VERIFY_RESULT_OK is returned if everything is verified
220 * correctly and all public keys are accepted.
221 *
222 * AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED is returned if
223 * everything is verified correctly out but one or more public keys
224 * are not accepted. This includes the case where integrity data is
225 * not signed.
226 *
227 * AVB_SLOT_VERIFY_RESULT_ERROR_OOM is returned if unable to
228 * allocate memory.
229 *
230 * AVB_SLOT_VERIFY_RESULT_ERROR_IO is returned if an I/O error
231 * occurred while trying to load data or get a rollback index.
232 *
233 * AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION is returned if the data
234 * did not verify, e.g. the digest didn't match or signature checks
235 * failed.
236 *
237 * AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX is returned if a
238 * rollback index was less than its stored value.
239 *
240 * AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA is returned if some
241 * of the metadata is invalid or inconsistent.
David Zeuthene3cadca2017-02-22 21:25:46 -0500242 *
243 * AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION is returned if
244 * some of the metadata requires a newer version of libavb than what
245 * is in use.
David Zeuthen21e95262016-07-27 17:58:40 -0400246 */
David Zeuthena8bb9a02016-10-28 14:36:55 -0400247AvbSlotVerifyResult avb_slot_verify(AvbOps* ops,
248 const char* const* requested_partitions,
249 const char* ab_suffix,
David Zeuthen0155e6b2016-11-16 17:58:13 -0500250 bool allow_verification_error,
David Zeuthen21e95262016-07-27 17:58:40 -0400251 AvbSlotVerifyData** out_data);
252
253#ifdef __cplusplus
254}
255#endif
256
257#endif /* AVB_SLOT_VERIFY_H_ */