1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * 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: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * 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. 23 */ 24 25 #ifndef AVB_OPS_USER_H_ 26 #define AVB_OPS_USER_H_ 27 28 #include <android_avb/libavb.h> 29 #include <android_avb/avb_ab_flow.h> 30 31 #define PERM_ATTR_DIGEST_SIZE 32 32 #define PERM_ATTR_TOTAL_SIZE 1084 33 34 /* Allocates an AvbOps instance suitable for use in Android userspace 35 * on the device. Returns NULL on OOM. 36 * 37 * The returned AvbOps has the following characteristics: 38 * 39 * - The read_from_partition(), write_to_partition(), and 40 * get_size_of_partition() operations are implemented, however for 41 * these operations to work the fstab file on the device must have a 42 * /misc entry using a by-name device file scheme and the containing 43 * by-name/ subdirectory must have files for other partitions. 44 * 45 * - The remaining operations are implemented and never fails and 46 * return the following values: 47 * - validate_vbmeta_public_key(): always returns |true|. 48 * - read_rollback_index(): returns 0 for any roolback index. 49 * - write_rollback_index(): no-op. 50 * - read_is_device_unlocked(): always returns |true|. 51 * - get_unique_guid_for_partition(): always returns the empty string. 52 * 53 * - The |ab_ops| member will point to a valid AvbABOps instance 54 * implemented via libavb_ab/. This should only be used if the AVB 55 * A/B stack is used on the device. This is what is used in 56 * bootctrl.avb boot control implementation. 57 * 58 * Free with avb_ops_user_free(). 59 */ 60 AvbOps* avb_ops_user_new(void); 61 62 /* Frees an AvbOps instance previously allocated with avb_ops_device_new(). */ 63 void avb_ops_user_free(AvbOps* ops); 64 65 /** 66 * Provided to fastboot to read how many slot in this system. 67 * 68 * @param slot_count We use parameter slot_count to obtain 69 * how many slots in the system. 70 * 71 * @return 0 if the command succeeded, -1 if it failed 72 */ 73 int avb_read_slot_count(char *slot_count); 74 75 /** 76 * The android things supply many slots, their name like '_a', '_b'. 77 * We can use this function to read current slot is '_a' or '_b'. 78 * 79 * @slot_suffixes read value '_a' or '_b'. 80 * 81 * @return 0 if the command succeeded, -1 if it failed 82 */ 83 int avb_read_slot_suffixes(char *slot_suffixes); 84 85 /** 86 * Use this function to set which slot boot first. 87 * 88 * @param slot_number set '0' or '1' 89 * 90 * @return 0 if the command succeeded, -1 if it failed 91 */ 92 int avb_set_slot_active(unsigned int *slot_number); 93 94 /** 95 * Get current slot: '_a' or '_b'. 96 * 97 * @param select_slot obtain current slot. 98 * 99 * @return 0 if the command succeeded, -1 if it failed 100 */ 101 int avb_get_current_slot(char *select_slot); 102 103 /** 104 * The android things defines permanent attributes to 105 * store PSK_public, product id. We can use this function 106 * to read them. 107 * 108 * @param attributes PSK_public, product id.... 109 * 110 * @param size The size of attributes. 111 * 112 * @return 0 if the command succeeded, -1 if it failed 113 */ 114 int avb_read_permanent_attributes(uint8_t *attributes, uint32_t size); 115 116 /** 117 * The android things defines permanent attributes to 118 * store PSK_public, product id. We can use this function 119 * to write them. 120 * 121 * @param attributes PSK_public, product id.... 122 * 123 * @param size The size of attributes. 124 * 125 * @return 0 if the command succeeded, -1 if it failed 126 */ 127 int avb_write_permanent_attributes(uint8_t *attributes, uint32_t size); 128 129 /** 130 * The funtion can be use to read the device state to judge 131 * whether the device can be flash. 132 * 133 * @param flash_lock_state A flag indicate the device flash state. 134 * 135 * @return 0 if the command succeeded, -1 if it failed 136 */ 137 int avb_read_flash_lock_state(uint8_t *flash_lock_state); 138 139 /** 140 * The function is provided to write device flash state. 141 * 142 * @param flash_lock_state A flag indicate the device flash state. 143 * 144 * @return 0 if the command succeeded, -1 if it failed 145 */ 146 int avb_write_flash_lock_state(uint8_t flash_lock_state); 147 148 /** 149 * The android things use the flag of lock state to indicate 150 * whether the device can be booted when verified error. 151 * 152 * @param lock_state A flag indicate the device lock state. 153 * 154 * @return 0 if the command succeeded, -1 if it failed 155 */ 156 int avb_read_lock_state(uint8_t *lock_state); 157 158 /** 159 * The android things use the flag of lock state to indicate 160 * whether the device can be booted when verified error. 161 * 162 * @param lock_state A flag indicate the device lock state. 163 * 164 * @return 0 if the command succeeded, -1 if it failed 165 */ 166 int avb_write_lock_state(uint8_t lock_state); 167 168 /** 169 * The android things uses fastboot to flash the permanent attributes. 170 * And if them were written, there must have a flag to indicate. 171 * 172 * @param flag indicate the permanent attributes have been written 173 * or not. 174 * 175 * @return 0 if the command succeeded, -1 if it failed 176 */ 177 int avb_read_perm_attr_flag(uint8_t *flag); 178 179 /** 180 * The android things uses fastboot to flash the permanent attributes. 181 * And if them were written, there must have a flag to indicate. 182 * 183 * @param flag We can call this function to write the flag '1' 184 * to indicate the permanent attributes has been 185 * written. 186 * 187 * @return 0 if the command succeeded, -1 if it failed 188 */ 189 int avb_write_perm_attr_flag(uint8_t flag); 190 191 #endif 192