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: c784ce50e8c10eaf70e1f97e24e8324aef45faf5 6 * 7 * Copyright (C) 2008 The Android Open Source Project 8 * 9 * SPDX-License-Identifier: BSD-3-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 For 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. */ 27static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0; 28static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024; 29 30/* Bootloader Message (2-KiB) 31 * 32 * This structure describes the content of a block in flash 33 * that is used for recovery and the bootloader to talk to 34 * each other. 35 * 36 * The command field is updated by linux when it wants to 37 * reboot into recovery or to update radio or bootloader firmware. 38 * It is also updated by the bootloader when firmware update 39 * is complete (to boot into recovery for any final cleanup) 40 * 41 * The status field was used by the bootloader after the completion 42 * of an "update-radio" or "update-hboot" command, which has been 43 * deprecated since Froyo. 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 */ 59struct 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) 83static_assert(sizeof(struct 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 * The update_channel field is used to store the Omaha update channel 104 * if update_engine is compiled with Omaha support. 105 */ 106struct bootloader_message_ab { 107 struct bootloader_message message; 108 char slot_suffix[32]; 109 char update_channel[128]; 110 111 /* Round up the entire struct to 4096-byte. */ 112 char reserved[1888]; 113}; 114 115/** 116 * Be cautious about the struct size change, in case we put anything post 117 * bootloader_message_ab struct (b/29159185). 118 */ 119#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) 120static_assert(sizeof(struct bootloader_message_ab) == 4096, 121 "struct bootloader_message_ab size changes"); 122#endif 123 124#define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */ 125#define BOOT_CTRL_VERSION 1 126 127struct slot_metadata { 128 /* Slot priority with 15 meaning highest priority, 1 lowest 129 * priority and 0 the slot is unbootable. */ 130 uint8_t priority : 4; 131 /* Number of times left attempting to boot this slot. */ 132 uint8_t tries_remaining : 3; 133 /* 1 if this slot has booted successfully, 0 otherwise. */ 134 uint8_t successful_boot : 1; 135 /* 1 if this slot is corrupted from a dm-verity corruption, 0 136 * otherwise. */ 137 uint8_t verity_corrupted : 1; 138 /* Reserved for further use. */ 139 uint8_t reserved : 7; 140} __attribute__((packed)); 141 142/* Bootloader Control AB 143 * 144 * This struct can be used to manage A/B metadata. It is designed to 145 * be put in the 'slot_suffix' field of the 'bootloader_message' 146 * structure described above. It is encouraged to use the 147 * 'bootloader_control' structure to store the A/B metadata, but not 148 * mandatory. 149 */ 150struct bootloader_control { 151 /* NUL terminated active slot suffix. */ 152 char slot_suffix[4]; 153 /* Bootloader Control AB magic number (see BOOT_CTRL_MAGIC). */ 154 uint32_t magic; 155 /* Version of struct being used (see BOOT_CTRL_VERSION). */ 156 uint8_t version; 157 /* Number of slots being managed. */ 158 uint8_t nb_slot : 3; 159 /* Number of times left attempting to boot recovery. */ 160 uint8_t recovery_tries_remaining : 3; 161 /* Ensure 4-bytes alignment for slot_info field. */ 162 uint8_t reserved0[2]; 163 /* Per-slot information. Up to 4 slots. */ 164 struct slot_metadata slot_info[4]; 165 /* Reserved for further use. */ 166 uint8_t reserved1[8]; 167 /* CRC32 of all 28 bytes preceding this field (little endian 168 * format). */ 169 uint32_t crc32_le; 170} __attribute__((packed)); 171 172#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) 173static_assert(sizeof(struct bootloader_control) == 174 sizeof(((struct bootloader_message_ab *)0)->slot_suffix), 175 "struct bootloader_control has wrong size"); 176#endif 177 178#ifndef __UBOOT__ 179 180#ifdef __cplusplus 181 182#include <string> 183#include <vector> 184 185/* Return the block device name for the bootloader message partition and waits 186 * for the device for up to 10 seconds. In case of error returns the empty 187 * string. */ 188std::string get_bootloader_message_blk_device(std::string* err); 189 190/* Read bootloader message into boot. Error message will be set in err. */ 191bool read_bootloader_message(bootloader_message* boot, std::string* err); 192 193/* Read bootloader message from the specified misc device into boot. */ 194bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device, 195 std::string* err); 196 197/* Write bootloader message to BCB. */ 198bool write_bootloader_message(const bootloader_message& boot, std::string* err); 199 200/* Write bootloader message to the specified BCB device. */ 201bool write_bootloader_message_to(const bootloader_message& boot, 202 const std::string& misc_blk_device, std::string* err); 203 204/* Write bootloader message (boots into recovery with the options) to BCB. Will 205 * set the command and recovery fields, and reset the rest. */ 206bool write_bootloader_message(const std::vector<std::string>& options, std::string* err); 207 208/* Write bootloader message (boots into recovery with the options) to the specific BCB device. Will 209 * set the command and recovery fields, and reset the rest. */ 210bool write_bootloader_message_to(const std::vector<std::string>& options, 211 const std::string& misc_blk_device, std::string* err); 212 213/* Update bootloader message (boots into recovery with the options) to BCB. Will 214 * only update the command and recovery fields. */ 215bool update_bootloader_message(const std::vector<std::string>& options, std::string* err); 216 217/* Update bootloader message (boots into recovery with the |options|) in |boot|. Will only update 218 * the command and recovery fields. */ 219bool update_bootloader_message_in_struct(bootloader_message* boot, 220 const std::vector<std::string>& options); 221 222/* Clear BCB. */ 223bool clear_bootloader_message(std::string* err); 224 225/* Writes the reboot-bootloader reboot reason to the bootloader_message. */ 226bool write_reboot_bootloader(std::string* err); 227 228/* Read the wipe package from BCB (from offset WIPE_PACKAGE_OFFSET_IN_MISC). */ 229bool read_wipe_package(std::string* package_data, size_t size, std::string* err); 230 231/* Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC). */ 232bool write_wipe_package(const std::string& package_data, std::string* err); 233 234#else 235 236#include <stdbool.h> 237 238/* C Interface. */ 239bool write_bootloader_message(const char* options); 240bool write_reboot_bootloader(void); 241 242#endif /* ifdef __cplusplus */ 243 244#endif /* __UBOOT__ */ 245 246#endif /* __ANDROID_BOOTLOADER_MESSAGE_H */ 247