1 /* 2 * This is from the Android Project, 3 * Repository: https://android.googlesource.com/platform/bootable/recovery/ 4 * File: bootloader_message/include/bootloader_message/bootloader_message.h 5 * Commit: 8b309f6970ab3b7c53cc529c51a2cb44e1c7a7e1 6 * 7 * Copyright (C) 2008 The Android Open Source Project 8 * 9 * SPDX-License-Identifier: BSD-2-Clause 10 */ 11 12 #ifndef __ANDROID_BOOTLOADER_MESSAGE_H 13 #define __ANDROID_BOOTLOADER_MESSAGE_H 14 15 /* compiler.h defines the types that otherwise are included from stdint.h and 16 * stddef.h 17 */ 18 #include <compiler.h> 19 20 /* Spaces used by misc partition are as below: 21 * 0 - 2K Bootloader Message 22 * 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used 23 * as bootloader_message_ab struct) 24 * 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices 25 * Note that these offsets are admitted by bootloader,recovery and uncrypt, so they 26 * are not configurable without changing all of them. 27 */ 28 static const size_t ANDROID_BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0; 29 static const size_t ANDROID_WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024; 30 31 /* Bootloader Message (2-KiB) 32 * 33 * This structure describes the content of a block in flash 34 * that is used for recovery and the bootloader to talk to 35 * each other. 36 * 37 * The command field is updated by linux when it wants to 38 * reboot into recovery or to update radio or bootloader firmware. 39 * It is also updated by the bootloader when firmware update 40 * is complete (to boot into recovery for any final cleanup) 41 * 42 * The status field is written by the bootloader after the 43 * completion of an "update-radio" or "update-hboot" command. 44 * 45 * The recovery field is only written by linux and used 46 * for the system to send a message to recovery or the 47 * other way around. 48 * 49 * The stage field is written by packages which restart themselves 50 * multiple times, so that the UI can reflect which invocation of the 51 * package it is. If the value is of the format "#/#" (eg, "1/3"), 52 * the UI will add a simple indicator of that status. 53 * 54 * We used to have slot_suffix field for A/B boot control metadata in 55 * this struct, which gets unintentionally cleared by recovery or 56 * uncrypt. Move it into struct bootloader_message_ab to avoid the 57 * issue. 58 */ 59 struct android_bootloader_message { 60 char command[32]; 61 char status[32]; 62 char recovery[768]; 63 64 /* The 'recovery' field used to be 1024 bytes. It has only ever 65 * been used to store the recovery command line, so 768 bytes 66 * should be plenty. We carve off the last 256 bytes to store the 67 * stage string (for multistage packages) and possible future 68 * expansion. */ 69 char stage[32]; 70 71 /* The 'reserved' field used to be 224 bytes when it was initially 72 * carved off from the 1024-byte recovery field. Bump it up to 73 * 1184-byte so that the entire bootloader_message struct rounds up 74 * to 2048-byte. */ 75 char reserved[1184]; 76 }; 77 78 /** 79 * We must be cautious when changing the bootloader_message struct size, 80 * because A/B-specific fields may end up with different offsets. 81 */ 82 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) 83 static_assert(sizeof(struct android_bootloader_message) == 2048, 84 "struct bootloader_message size changes, which may break A/B devices"); 85 #endif 86 87 /** 88 * The A/B-specific bootloader message structure (4-KiB). 89 * 90 * We separate A/B boot control metadata from the regular bootloader 91 * message struct and keep it here. Everything that's A/B-specific 92 * stays after struct bootloader_message, which should be managed by 93 * the A/B-bootloader or boot control HAL. 94 * 95 * The slot_suffix field is used for A/B implementations where the 96 * bootloader does not set the androidboot.ro.boot.slot_suffix kernel 97 * commandline parameter. This is used by fs_mgr to mount /system and 98 * other partitions with the slotselect flag set in fstab. A/B 99 * implementations are free to use all 32 bytes and may store private 100 * data past the first NUL-byte in this field. It is encouraged, but 101 * not mandatory, to use 'struct bootloader_control' described below. 102 */ 103 struct android_bootloader_message_ab { 104 struct android_bootloader_message message; 105 char slot_suffix[32]; 106 107 /* Round up the entire struct to 4096-byte. */ 108 char reserved[2016]; 109 }; 110 111 /** 112 * Be cautious about the struct size change, in case we put anything post 113 * bootloader_message_ab struct (b/29159185). 114 */ 115 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) 116 static_assert(sizeof(struct android_bootloader_message_ab) == 4096, 117 "struct bootloader_message_ab size changes"); 118 #endif 119 120 #define ANDROID_BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */ 121 #define ANDROID_BOOT_CTRL_VERSION 1 122 123 struct android_slot_metadata { 124 /* Slot priority with 15 meaning highest priority, 1 lowest 125 * priority and 0 the slot is unbootable. */ 126 uint8_t priority : 4; 127 /* Number of times left attempting to boot this slot. */ 128 uint8_t tries_remaining : 3; 129 /* 1 if this slot has booted successfully, 0 otherwise. */ 130 uint8_t successful_boot : 1; 131 /* 1 if this slot is corrupted from a dm-verity corruption, 0 */ 132 /* otherwise. */ 133 uint8_t verity_corrupted : 1; 134 /* Reserved for further use. */ 135 uint8_t reserved : 7; 136 } __attribute__((packed)); 137 138 /* Bootloader Control AB 139 * 140 * This struct can be used to manage A/B metadata. It is designed to 141 * be put in the 'slot_suffix' field of the 'bootloader_message' 142 * structure described above. It is encouraged to use the 143 * 'bootloader_control' structure to store the A/B metadata, but not 144 * mandatory. 145 */ 146 struct android_bootloader_control { 147 /* NUL terminated active slot suffix. */ 148 char slot_suffix[4]; 149 /* Bootloader Control AB magic number (see BOOT_CTRL_MAGIC). */ 150 uint32_t magic; 151 /* Version of struct being used (see BOOT_CTRL_VERSION). */ 152 uint8_t version; 153 /* Number of slots being managed. */ 154 uint8_t nb_slot : 3; 155 /* Number of times left attempting to boot recovery. */ 156 uint8_t recovery_tries_remaining : 3; 157 /* Ensure 4-bytes alignment for slot_info field. */ 158 uint8_t reserved0[2]; 159 /* Per-slot information. Up to 4 slots. */ 160 struct android_slot_metadata slot_info[4]; 161 /* Reserved for further use. */ 162 uint8_t reserved1[8]; 163 /* CRC32 of all 28 bytes preceding this field (little endian 164 * format). */ 165 uint32_t crc32_le; 166 } __attribute__((packed)); 167 168 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) 169 static_assert(sizeof(struct android_bootloader_control) == 170 sizeof(((struct android_bootloader_message_ab *)0)->slot_suffix), 171 "struct bootloader_control has wrong size"); 172 #endif 173 174 #endif /* __ANDROID_BOOTLOADER_MESSAGE_H */ 175