/* * This is from the Android Project, * Repository: https://android.googlesource.com/platform/bootable/recovery * File: bootloader_message/include/bootloader_message/bootloader_message.h * Commit: c784ce50e8c10eaf70e1f97e24e8324aef45faf5 * * Copyright (C) 2008 The Android Open Source Project * * SPDX-License-Identifier: BSD-3-Clause */ #ifndef __ANDROID_BOOTLOADER_MESSAGE_H #define __ANDROID_BOOTLOADER_MESSAGE_H /* compiler.h defines the types that otherwise are included from stdint.h and * stddef.h */ #include /* Spaces used by misc partition are as below: * 0 - 2K For bootloader_message * 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used * as bootloader_message_ab struct) * 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices * Note that these offsets are admitted by bootloader,recovery and uncrypt, so they * are not configurable without changing all of them. */ static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0; static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024; /* Bootloader Message (2-KiB) * * This structure describes the content of a block in flash * that is used for recovery and the bootloader to talk to * each other. * * The command field is updated by linux when it wants to * reboot into recovery or to update radio or bootloader firmware. * It is also updated by the bootloader when firmware update * is complete (to boot into recovery for any final cleanup) * * The status field was used by the bootloader after the completion * of an "update-radio" or "update-hboot" command, which has been * deprecated since Froyo. * * The recovery field is only written by linux and used * for the system to send a message to recovery or the * other way around. * * The stage field is written by packages which restart themselves * multiple times, so that the UI can reflect which invocation of the * package it is. If the value is of the format "#/#" (eg, "1/3"), * the UI will add a simple indicator of that status. * * We used to have slot_suffix field for A/B boot control metadata in * this struct, which gets unintentionally cleared by recovery or * uncrypt. Move it into struct bootloader_message_ab to avoid the * issue. */ struct bootloader_message { char command[32]; char status[32]; char recovery[768]; /* The 'recovery' field used to be 1024 bytes. It has only ever * been used to store the recovery command line, so 768 bytes * should be plenty. We carve off the last 256 bytes to store the * stage string (for multistage packages) and possible future * expansion. */ char stage[32]; /* The 'reserved' field used to be 224 bytes when it was initially * carved off from the 1024-byte recovery field. Bump it up to * 1184-byte so that the entire bootloader_message struct rounds up * to 2048-byte. */ char reserved[1184]; }; /** * We must be cautious when changing the bootloader_message struct size, * because A/B-specific fields may end up with different offsets. */ #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_message) == 2048, "struct bootloader_message size changes, which may break A/B devices"); #endif /** * The A/B-specific bootloader message structure (4-KiB). * * We separate A/B boot control metadata from the regular bootloader * message struct and keep it here. Everything that's A/B-specific * stays after struct bootloader_message, which should be managed by * the A/B-bootloader or boot control HAL. * * The slot_suffix field is used for A/B implementations where the * bootloader does not set the androidboot.ro.boot.slot_suffix kernel * commandline parameter. This is used by fs_mgr to mount /system and * other partitions with the slotselect flag set in fstab. A/B * implementations are free to use all 32 bytes and may store private * data past the first NUL-byte in this field. It is encouraged, but * not mandatory, to use 'struct bootloader_control' described below. * * The update_channel field is used to store the Omaha update channel * if update_engine is compiled with Omaha support. */ struct bootloader_message_ab { struct bootloader_message message; char slot_suffix[32]; char update_channel[128]; /* Round up the entire struct to 4096-byte. */ char reserved[1888]; }; /** * Be cautious about the struct size change, in case we put anything post * bootloader_message_ab struct (b/29159185). */ #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_message_ab) == 4096, "struct bootloader_message_ab size changes"); #endif #define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */ #define BOOT_CTRL_VERSION 1 struct slot_metadata { /* Slot priority with 15 meaning highest priority, 1 lowest * priority and 0 the slot is unbootable. */ uint8_t priority : 4; /* Number of times left attempting to boot this slot. */ uint8_t tries_remaining : 3; /* 1 if this slot has booted successfully, 0 otherwise. */ uint8_t successful_boot : 1; /* 1 if this slot is corrupted from a dm-verity corruption, 0 * otherwise. */ uint8_t verity_corrupted : 1; /* Reserved for further use. */ uint8_t reserved : 7; } __attribute__((packed)); /* Bootloader Control AB * * This struct can be used to manage A/B metadata. It is designed to * be put in the 'slot_suffix' field of the 'bootloader_message' * structure described above. It is encouraged to use the * 'bootloader_control' structure to store the A/B metadata, but not * mandatory. */ struct bootloader_control { /* NUL terminated active slot suffix. */ char slot_suffix[4]; /* Bootloader Control AB magic number (see BOOT_CTRL_MAGIC). */ uint32_t magic; /* Version of struct being used (see BOOT_CTRL_VERSION). */ uint8_t version; /* Number of slots being managed. */ uint8_t nb_slot : 3; /* Number of times left attempting to boot recovery. */ uint8_t recovery_tries_remaining : 3; /* Ensure 4-bytes alignment for slot_info field. */ uint8_t reserved0[2]; /* Per-slot information. Up to 4 slots. */ struct slot_metadata slot_info[4]; /* Reserved for further use. */ uint8_t reserved1[8]; /* CRC32 of all 28 bytes preceding this field (little endian * format). */ uint32_t crc32_le; } __attribute__((packed)); #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_control) == sizeof(((struct bootloader_message_ab *)0)->slot_suffix), "struct bootloader_control has wrong size"); #endif #ifndef __UBOOT__ #ifdef __cplusplus #include #include /* Return the block device name for the bootloader message partition and waits * for the device for up to 10 seconds. In case of error returns the empty * string. */ std::string get_bootloader_message_blk_device(std::string* err); /* Read bootloader message into boot. Error message will be set in err. */ bool read_bootloader_message(bootloader_message* boot, std::string* err); /* Read bootloader message from the specified misc device into boot. */ bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device, std::string* err); /* Write bootloader message to BCB. */ bool write_bootloader_message(const bootloader_message& boot, std::string* err); /* Write bootloader message to the specified BCB device. */ bool write_bootloader_message_to(const bootloader_message& boot, const std::string& misc_blk_device, std::string* err); /* Write bootloader message (boots into recovery with the options) to BCB. Will * set the command and recovery fields, and reset the rest. */ bool write_bootloader_message(const std::vector& options, std::string* err); /* Write bootloader message (boots into recovery with the options) to the specific BCB device. Will * set the command and recovery fields, and reset the rest. */ bool write_bootloader_message_to(const std::vector& options, const std::string& misc_blk_device, std::string* err); /* Update bootloader message (boots into recovery with the options) to BCB. Will * only update the command and recovery fields. */ bool update_bootloader_message(const std::vector& options, std::string* err); /* Update bootloader message (boots into recovery with the |options|) in |boot|. Will only update * the command and recovery fields. */ bool update_bootloader_message_in_struct(bootloader_message* boot, const std::vector& options); /* Clear BCB. */ bool clear_bootloader_message(std::string* err); /* Writes the reboot-bootloader reboot reason to the bootloader_message. */ bool write_reboot_bootloader(std::string* err); /* Read the wipe package from BCB (from offset WIPE_PACKAGE_OFFSET_IN_MISC). */ bool read_wipe_package(std::string* package_data, size_t size, std::string* err); /* Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC). */ bool write_wipe_package(const std::string& package_data, std::string* err); #else #include /* C Interface. */ bool write_bootloader_message(const char* options); bool write_reboot_bootloader(void); #endif /* ifdef __cplusplus */ #endif /* __UBOOT__ */ #endif /* __ANDROID_BOOTLOADER_MESSAGE_H */