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authorDavid Anderson <dvander@google.com>2019-08-29 00:24:07 +0200
committerDavid Anderson <dvander@google.com>2019-08-30 19:20:59 +0200
commit8108e2513f8342444821c179d713982fcf931e98 (patch)
treed331f6b824134d167b7f6cf1a9321f320f9a7a31 /boot_control/boot_control.cpp
parentMerge "updater: Fix build for new CreateLogicalPartition signature." (diff)
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Diffstat (limited to 'boot_control/boot_control.cpp')
-rw-r--r--boot_control/boot_control.cpp401
1 files changed, 0 insertions, 401 deletions
diff --git a/boot_control/boot_control.cpp b/boot_control/boot_control.cpp
deleted file mode 100644
index ec97b6ced..000000000
--- a/boot_control/boot_control.cpp
+++ /dev/null
@@ -1,401 +0,0 @@
-/*
- * Copyright (C) 2015 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <endian.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <string.h>
-
-#include <string>
-
-#include <android-base/file.h>
-#include <android-base/logging.h>
-#include <android-base/properties.h>
-#include <android-base/stringprintf.h>
-#include <android-base/unique_fd.h>
-#include <hardware/boot_control.h>
-#include <hardware/hardware.h>
-
-#include <bootloader_message/bootloader_message.h>
-
-struct boot_control_private_t {
- // The base struct needs to be first in the list.
- boot_control_module_t base;
-
- // Whether this struct was initialized with data from the bootloader message
- // that doesn't change until next reboot.
- bool initialized;
-
- // The path to the misc_device as reported in the fstab.
- const char* misc_device;
-
- // The number of slots present on the device.
- unsigned int num_slots;
-
- // The slot where we are running from.
- unsigned int current_slot;
-};
-
-namespace {
-
-// The number of boot attempts that should be made from a new slot before
-// rolling back to the previous slot.
-constexpr unsigned int kDefaultBootAttempts = 7;
-static_assert(kDefaultBootAttempts < 8, "tries_remaining field only has 3 bits");
-
-constexpr unsigned int kMaxNumSlots =
- sizeof(bootloader_control::slot_info) / sizeof(bootloader_control::slot_info[0]);
-constexpr const char* kSlotSuffixes[kMaxNumSlots] = { "_a", "_b", "_c", "_d" };
-constexpr off_t kBootloaderControlOffset = offsetof(bootloader_message_ab, slot_suffix);
-
-static uint32_t CRC32(const uint8_t* buf, size_t size) {
- static uint32_t crc_table[256];
-
- // Compute the CRC-32 table only once.
- if (!crc_table[1]) {
- for (uint32_t i = 0; i < 256; ++i) {
- uint32_t crc = i;
- for (uint32_t j = 0; j < 8; ++j) {
- uint32_t mask = -(crc & 1);
- crc = (crc >> 1) ^ (0xEDB88320 & mask);
- }
- crc_table[i] = crc;
- }
- }
-
- uint32_t ret = -1;
- for (size_t i = 0; i < size; ++i) {
- ret = (ret >> 8) ^ crc_table[(ret ^ buf[i]) & 0xFF];
- }
-
- return ~ret;
-}
-
-// Return the little-endian representation of the CRC-32 of the first fields
-// in |boot_ctrl| up to the crc32_le field.
-uint32_t BootloaderControlLECRC(const bootloader_control* boot_ctrl) {
- return htole32(
- CRC32(reinterpret_cast<const uint8_t*>(boot_ctrl), offsetof(bootloader_control, crc32_le)));
-}
-
-bool LoadBootloaderControl(const char* misc_device, bootloader_control* buffer) {
- android::base::unique_fd fd(open(misc_device, O_RDONLY));
- if (fd.get() == -1) {
- PLOG(ERROR) << "failed to open " << misc_device;
- return false;
- }
- if (lseek(fd, kBootloaderControlOffset, SEEK_SET) != kBootloaderControlOffset) {
- PLOG(ERROR) << "failed to lseek " << misc_device;
- return false;
- }
- if (!android::base::ReadFully(fd.get(), buffer, sizeof(bootloader_control))) {
- PLOG(ERROR) << "failed to read " << misc_device;
- return false;
- }
- return true;
-}
-
-bool UpdateAndSaveBootloaderControl(const char* misc_device, bootloader_control* buffer) {
- buffer->crc32_le = BootloaderControlLECRC(buffer);
- android::base::unique_fd fd(open(misc_device, O_WRONLY | O_SYNC));
- if (fd.get() == -1) {
- PLOG(ERROR) << "failed to open " << misc_device;
- return false;
- }
- if (lseek(fd.get(), kBootloaderControlOffset, SEEK_SET) != kBootloaderControlOffset) {
- PLOG(ERROR) << "failed to lseek " << misc_device;
- return false;
- }
- if (!android::base::WriteFully(fd.get(), buffer, sizeof(bootloader_control))) {
- PLOG(ERROR) << "failed to write " << misc_device;
- return false;
- }
- return true;
-}
-
-void InitDefaultBootloaderControl(const boot_control_private_t* module,
- bootloader_control* boot_ctrl) {
- memset(boot_ctrl, 0, sizeof(*boot_ctrl));
-
- if (module->current_slot < kMaxNumSlots) {
- strlcpy(boot_ctrl->slot_suffix, kSlotSuffixes[module->current_slot],
- sizeof(boot_ctrl->slot_suffix));
- }
- boot_ctrl->magic = BOOT_CTRL_MAGIC;
- boot_ctrl->version = BOOT_CTRL_VERSION;
-
- // Figure out the number of slots by checking if the partitions exist,
- // otherwise assume the maximum supported by the header.
- boot_ctrl->nb_slot = kMaxNumSlots;
- std::string base_path = module->misc_device;
- size_t last_path_sep = base_path.rfind('/');
- if (last_path_sep != std::string::npos) {
- // We test the existence of the "boot" partition on each possible slot,
- // which is a partition required by Android Bootloader Requirements.
- base_path = base_path.substr(0, last_path_sep + 1) + "boot";
- int last_existing_slot = -1;
- int first_missing_slot = -1;
- for (unsigned int slot = 0; slot < kMaxNumSlots; ++slot) {
- std::string partition_path = base_path + kSlotSuffixes[slot];
- struct stat part_stat;
- int err = stat(partition_path.c_str(), &part_stat);
- if (!err) {
- last_existing_slot = slot;
- LOG(INFO) << "Found slot: " << kSlotSuffixes[slot];
- } else if (err < 0 && errno == ENOENT && first_missing_slot == -1) {
- first_missing_slot = slot;
- }
- }
- // We only declare that we found the actual number of slots if we found all
- // the boot partitions up to the number of slots, and no boot partition
- // after that. Not finding any of the boot partitions implies a problem so
- // we just leave the number of slots in the maximum value.
- if ((last_existing_slot != -1 && last_existing_slot + 1 == first_missing_slot) ||
- (first_missing_slot == -1 && last_existing_slot + 1 == kMaxNumSlots)) {
- boot_ctrl->nb_slot = last_existing_slot + 1;
- LOG(INFO) << "Found a system with " << last_existing_slot + 1 << " slots.";
- }
- }
-
- for (unsigned int slot = 0; slot < kMaxNumSlots; ++slot) {
- slot_metadata entry = {};
-
- if (slot < boot_ctrl->nb_slot) {
- entry.priority = 7;
- entry.tries_remaining = kDefaultBootAttempts;
- entry.successful_boot = 0;
- } else {
- entry.priority = 0; // Unbootable
- }
-
- // When the boot_control stored on disk is invalid, we assume that the
- // current slot is successful. The bootloader should repair this situation
- // before booting and write a valid boot_control slot, so if we reach this
- // stage it means that the misc partition was corrupted since boot.
- if (module->current_slot == slot) {
- entry.successful_boot = 1;
- }
-
- boot_ctrl->slot_info[slot] = entry;
- }
- boot_ctrl->recovery_tries_remaining = 0;
-
- boot_ctrl->crc32_le = BootloaderControlLECRC(boot_ctrl);
-}
-
-// Return the index of the slot suffix passed or -1 if not a valid slot suffix.
-int SlotSuffixToIndex(const char* suffix) {
- for (unsigned int slot = 0; slot < kMaxNumSlots; ++slot) {
- if (!strcmp(kSlotSuffixes[slot], suffix)) return slot;
- }
- return -1;
-}
-
-// Initialize the boot_control_private struct with the information from
-// the bootloader_message buffer stored in |boot_ctrl|. Returns whether the
-// initialization succeeded.
-bool BootControl_lazyInitialization(boot_control_private_t* module) {
- if (module->initialized) return true;
-
- // Initialize the current_slot from the read-only property. If the property
- // was not set (from either the command line or the device tree), we can later
- // initialize it from the bootloader_control struct.
- std::string suffix_prop = android::base::GetProperty("ro.boot.slot_suffix", "");
- module->current_slot = SlotSuffixToIndex(suffix_prop.c_str());
-
- std::string err;
- std::string device = get_bootloader_message_blk_device(&err);
- if (device.empty()) return false;
-
- bootloader_control boot_ctrl;
- if (!LoadBootloaderControl(device.c_str(), &boot_ctrl)) return false;
-
- // Note that since there isn't a module unload function this memory is leaked.
- module->misc_device = strdup(device.c_str());
- module->initialized = true;
-
- // Validate the loaded data, otherwise we will destroy it and re-initialize it
- // with the current information.
- uint32_t computed_crc32 = BootloaderControlLECRC(&boot_ctrl);
- if (boot_ctrl.crc32_le != computed_crc32) {
- LOG(WARNING) << "Invalid boot control found, expected CRC-32 0x" << std::hex << computed_crc32
- << " but found 0x" << std::hex << boot_ctrl.crc32_le << ". Re-initializing.";
- InitDefaultBootloaderControl(module, &boot_ctrl);
- UpdateAndSaveBootloaderControl(device.c_str(), &boot_ctrl);
- }
-
- module->num_slots = boot_ctrl.nb_slot;
- return true;
-}
-
-void BootControl_init(boot_control_module_t* module) {
- BootControl_lazyInitialization(reinterpret_cast<boot_control_private_t*>(module));
-}
-
-unsigned int BootControl_getNumberSlots(boot_control_module_t* module) {
- return reinterpret_cast<boot_control_private_t*>(module)->num_slots;
-}
-
-unsigned int BootControl_getCurrentSlot(boot_control_module_t* module) {
- return reinterpret_cast<boot_control_private_t*>(module)->current_slot;
-}
-
-int BootControl_markBootSuccessful(boot_control_module_t* module) {
- boot_control_private_t* const bootctrl_module = reinterpret_cast<boot_control_private_t*>(module);
-
- bootloader_control bootctrl;
- if (!LoadBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
-
- bootctrl.slot_info[bootctrl_module->current_slot].successful_boot = 1;
- // tries_remaining == 0 means that the slot is not bootable anymore, make
- // sure we mark the current slot as bootable if it succeeds in the last
- // attempt.
- bootctrl.slot_info[bootctrl_module->current_slot].tries_remaining = 1;
- if (!UpdateAndSaveBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
- return 0;
-}
-
-int BootControl_setActiveBootSlot(boot_control_module_t* module, unsigned int slot) {
- boot_control_private_t* const bootctrl_module = reinterpret_cast<boot_control_private_t*>(module);
-
- if (slot >= kMaxNumSlots || slot >= bootctrl_module->num_slots) {
- // Invalid slot number.
- return -1;
- }
-
- bootloader_control bootctrl;
- if (!LoadBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
-
- // Set every other slot with a lower priority than the new "active" slot.
- const unsigned int kActivePriority = 15;
- const unsigned int kActiveTries = 6;
- for (unsigned int i = 0; i < bootctrl_module->num_slots; ++i) {
- if (i != slot) {
- if (bootctrl.slot_info[i].priority >= kActivePriority)
- bootctrl.slot_info[i].priority = kActivePriority - 1;
- }
- }
-
- // Note that setting a slot as active doesn't change the successful bit.
- // The successful bit will only be changed by setSlotAsUnbootable().
- bootctrl.slot_info[slot].priority = kActivePriority;
- bootctrl.slot_info[slot].tries_remaining = kActiveTries;
-
- // Setting the current slot as active is a way to revert the operation that
- // set *another* slot as active at the end of an updater. This is commonly
- // used to cancel the pending update. We should only reset the verity_corrpted
- // bit when attempting a new slot, otherwise the verity bit on the current
- // slot would be flip.
- if (slot != bootctrl_module->current_slot) bootctrl.slot_info[slot].verity_corrupted = 0;
-
- if (!UpdateAndSaveBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
- return 0;
-}
-
-int BootControl_setSlotAsUnbootable(struct boot_control_module* module, unsigned int slot) {
- boot_control_private_t* const bootctrl_module = reinterpret_cast<boot_control_private_t*>(module);
-
- if (slot >= kMaxNumSlots || slot >= bootctrl_module->num_slots) {
- // Invalid slot number.
- return -1;
- }
-
- bootloader_control bootctrl;
- if (!LoadBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
-
- // The only way to mark a slot as unbootable, regardless of the priority is to
- // set the tries_remaining to 0.
- bootctrl.slot_info[slot].successful_boot = 0;
- bootctrl.slot_info[slot].tries_remaining = 0;
- if (!UpdateAndSaveBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
- return 0;
-}
-
-int BootControl_isSlotBootable(struct boot_control_module* module, unsigned int slot) {
- boot_control_private_t* const bootctrl_module = reinterpret_cast<boot_control_private_t*>(module);
-
- if (slot >= kMaxNumSlots || slot >= bootctrl_module->num_slots) {
- // Invalid slot number.
- return -1;
- }
-
- bootloader_control bootctrl;
- if (!LoadBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
-
- return bootctrl.slot_info[slot].tries_remaining;
-}
-
-int BootControl_isSlotMarkedSuccessful(struct boot_control_module* module, unsigned int slot) {
- boot_control_private_t* const bootctrl_module = reinterpret_cast<boot_control_private_t*>(module);
-
- if (slot >= kMaxNumSlots || slot >= bootctrl_module->num_slots) {
- // Invalid slot number.
- return -1;
- }
-
- bootloader_control bootctrl;
- if (!LoadBootloaderControl(bootctrl_module->misc_device, &bootctrl)) return -1;
-
- return bootctrl.slot_info[slot].successful_boot && bootctrl.slot_info[slot].tries_remaining;
-}
-
-const char* BootControl_getSuffix(boot_control_module_t* module, unsigned int slot) {
- if (slot >= kMaxNumSlots || slot >= reinterpret_cast<boot_control_private_t*>(module)->num_slots) {
- return NULL;
- }
- return kSlotSuffixes[slot];
-}
-
-static int BootControl_open(const hw_module_t* module __unused, const char* id __unused,
- hw_device_t** device __unused) {
- /* Nothing to do currently. */
- return 0;
-}
-
-struct hw_module_methods_t BootControl_methods = {
- .open = BootControl_open,
-};
-
-} // namespace
-
-boot_control_private_t HAL_MODULE_INFO_SYM = {
- .base =
- {
- .common =
- {
- .tag = HARDWARE_MODULE_TAG,
- .module_api_version = BOOT_CONTROL_MODULE_API_VERSION_0_1,
- .hal_api_version = HARDWARE_HAL_API_VERSION,
- .id = BOOT_CONTROL_HARDWARE_MODULE_ID,
- .name = "AOSP reference bootctrl HAL",
- .author = "The Android Open Source Project",
- .methods = &BootControl_methods,
- },
- .init = BootControl_init,
- .getNumberSlots = BootControl_getNumberSlots,
- .getCurrentSlot = BootControl_getCurrentSlot,
- .markBootSuccessful = BootControl_markBootSuccessful,
- .setActiveBootSlot = BootControl_setActiveBootSlot,
- .setSlotAsUnbootable = BootControl_setSlotAsUnbootable,
- .isSlotBootable = BootControl_isSlotBootable,
- .getSuffix = BootControl_getSuffix,
- .isSlotMarkedSuccessful = BootControl_isSlotMarkedSuccessful,
- },
- .initialized = false,
- .misc_device = nullptr,
- .num_slots = 0,
- .current_slot = 0,
-};