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kernelflinger.c
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kernelflinger.c
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/*
* Copyright (c) 2014, Intel Corporation
* All rights reserved.
*
* Author: Andrew Boie <[email protected]>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <efi.h>
#include <efiapi.h>
#include <efilib.h>
#include "openssl_support.h"
#include <openssl/sha.h>
#include <fastboot.h>
#include "vars.h"
#include "lib.h"
#include "security.h"
#include "acpi.h"
#include "android.h"
#include "ux.h"
#include "options.h"
#include "power.h"
#include "targets.h"
#include "unittest.h"
#include "em.h"
#include "storage.h"
#include "version.h"
#include "timer.h"
#ifdef HAL_AUTODETECT
#include "blobstore.h"
#endif
#include "oemvars.h"
#include "slot.h"
#ifdef RPMB_STORAGE
#include "rpmb.h"
#include "rpmb_storage.h"
#endif
#ifdef USE_TRUSTY
#include "trusty_interface.h"
#include "trusty_common.h"
#endif
#include "gpt.h"
#include "protocol.h"
#include "uefi_utils.h"
#include "security_interface.h"
#include "security_efi.h"
#ifdef USE_TPM
#include "tpm2_security.h"
#endif
/* Ensure this is embedded in the EFI binary somewhere */
static const CHAR16 __attribute__((used)) magic[] = L"### kernelflinger ###";
/* Default max wait time for console reset in units of milliseconds if no EFI
* variable is set for this platform.
* You want this value as small as possible as this is added to
* the boot time for EVERY boot
*/
#define EFI_RESET_WAIT_MS 200
/* Interval in ms to check on startup for initial press of magic key */
#define DETECT_KEY_STALL_TIME_MS 1
/* How long (in milliseconds) magic key should be held to force
* Fastboot mode
*/
#define FASTBOOT_HOLD_DELAY (2 * 1000)
/* Magic key to enter fastboot mode or revovery console */
#define MAGIC_KEY EV_DOWN
/* If we find this in the root of the EFI system partition, unconditionally
* enter Fastboot mode
*/
#define FASTBOOT_SENTINEL L"\\force_fastboot"
/* BIOS Capsule update file */
#define FWUPDATE_FILE L"\\BIOSUPDATE.fv"
#define KFSELF_FILE L"\\EFI\\BOOT\\kernelflinger.efi"
#define KFUPDATE_FILE L"\\EFI\\BOOT\\kernelflinger_new.efi"
#define KFBACKUP_FILE L"\\EFI\\BOOT\\kernelflinger_bak.efi"
#ifndef ARCH_X86_64
#define BOOTLOADER_FILE L"\\EFI\\BOOT\\bootia32.efi"
#define BOOTLOADER_FILE_BAK L"\\EFI\\BOOT\\bootia32_bak.efi"
#else
#define BOOTLOADER_FILE L"\\EFI\\BOOT\\bootx64.efi"
#define BOOTLOADER_FILE_BAK L"\\EFI\\BOOT\\bootx64_bak.efi"
#endif // ARCH_X86_64
/* Crash event menu settings:
* Maximum time between the first and the last watchdog reset. If the
* current difference exceeds this constant, the watchdog counter is
* reset to zero.
*/
#define WATCHDOG_DELAY (10 * 60)
static EFI_HANDLE g_disk_device;
static EFI_LOADED_IMAGE *g_loaded_image;
static VOID die(VOID) __attribute__ ((noreturn));
#if DEBUG_MESSAGES
static VOID print_rsci_values(VOID)
{
enum wake_sources raw_wake_source = rsci_get_wake_source();
enum reset_sources raw_reset_source = rsci_get_reset_source();
enum reset_types raw_reset_type = rsci_get_reset_type();
debug(L"wake_source = %s (0x%02hhx)",
wake_source_string(raw_wake_source),
raw_wake_source);
debug(L"reset_source = %s (0x%02hhx)",
reset_source_string(raw_reset_source),
raw_reset_source);
debug(L"reset_type = %s (0x%02hhx)",
reset_type_string(raw_reset_type),
raw_reset_type);
if (raw_reset_source == RESET_PLATFORM_SPECIFIC)
debug(L"reset_extra_info = 0x%08hhx", rsci_get_reset_extra_info());
}
#endif
static enum boot_target check_fastboot_sentinel(VOID)
{
debug(L"checking ESP for %s", FASTBOOT_SENTINEL);
if (file_exists(g_disk_device, FASTBOOT_SENTINEL))
return FASTBOOT;
return NORMAL_BOOT;
}
static enum boot_target check_magic_key(VOID)
{
unsigned long i;
EFI_STATUS ret = EFI_NOT_READY;
EFI_INPUT_KEY key;
unsigned long wait_ms = EFI_RESET_WAIT_MS;
/* Some systems require a short stall before we can be sure there
* wasn't a keypress at boot. Read the EFI variable which determines
* that time for this platform
*/
ret = get_efi_variable_long_from_str8(&loader_guid,
MAGIC_KEY_TIMEOUT_VAR,
&wait_ms);
if (EFI_ERROR(ret)) {
debug(L"Couldn't read timeout variable; assuming default");
} else {
if (wait_ms > 1000) {
debug(L"pathological magic key timeout, use default");
wait_ms = EFI_RESET_WAIT_MS;
}
}
debug(L"Reset wait time: %d", wait_ms);
/* Check for 'magic' key. Some BIOSes are flaky about this
* so wait for the ConIn to be ready after reset
*/
for (i = 0; i <= wait_ms; i += DETECT_KEY_STALL_TIME_MS) {
ret = uefi_call_wrapper(ST->ConIn->ReadKeyStroke, 2,
ST->ConIn, &key);
if (ret == EFI_SUCCESS || i == wait_ms)
break;
uefi_call_wrapper(BS->Stall, 1, DETECT_KEY_STALL_TIME_MS * 1000);
}
if (EFI_ERROR(ret))
return NORMAL_BOOT;
debug(L"ReadKeyStroke: (%d tries) %d %d", i, key.ScanCode, key.UnicodeChar);
if (ui_keycode_to_event(key.ScanCode) != MAGIC_KEY)
return NORMAL_BOOT;
if (ui_enforce_key_held(FASTBOOT_HOLD_DELAY, MAGIC_KEY))
return FASTBOOT;
return NORMAL_BOOT;
}
static enum boot_target check_bcb(CHAR16 **target_path, BOOLEAN *oneshot)
{
EFI_STATUS ret;
struct bootloader_message bcb;
CHAR16 *target = NULL;
enum boot_target t;
CHAR8 *bcb_cmd;
BOOLEAN dirty;
*oneshot = FALSE;
*target_path = NULL;
ret = read_bcb(MISC_LABEL, &bcb);
if (EFI_ERROR(ret)) {
error(L"Unable to read BCB");
t = NORMAL_BOOT;
goto out;
}
dirty = bcb.status[0] != '\0';
/* We own the status field; clear it in case there is any stale data */
bcb.status[0] = '\0';
bcb_cmd = (CHAR8 *)bcb.command;
if (!strncmpa(bcb_cmd, (CHAR8 *)"boot-", 5)) {
target = stra_to_str(bcb_cmd + 5);
debug(L"BCB boot target: '%s'", target);
} else if (!strncmpa(bcb_cmd, (CHAR8 *)"bootonce-", 9)) {
target = stra_to_str(bcb_cmd + 9);
bcb_cmd[0] = '\0';
dirty = TRUE;
debug(L"BCB oneshot boot target: '%s'", target);
*oneshot = TRUE;
}
if (dirty) {
ret = write_bcb(MISC_LABEL, &bcb);
if (EFI_ERROR(ret))
error(L"Unable to update BCB contents!");
}
if (!target) {
t = NORMAL_BOOT;
goto out;
}
if (target[0] == L'\\') {
UINTN len;
if (!file_exists(g_disk_device, target)) {
error(L"Specified BCB file '%s' doesn't exist",
target);
t = NORMAL_BOOT;
goto out;
}
len = StrLen(target);
if (len > 4) {
*target_path = StrDuplicate(target);
if (!StrCmp(target + (len - 4), L".efi") ||
!StrCmp(target + (len - 4), L".EFI")) {
t = ESP_EFI_BINARY;
} else {
t = ESP_BOOTIMAGE;
}
goto out;
}
error(L"BCB file '%s' appears to be malformed", target);
t = NORMAL_BOOT;
goto out;
}
t = name_to_boot_target(target);
if (t != UNKNOWN_TARGET)
goto out;
error(L"Unknown boot target in BCB: '%s'", target);
t = NORMAL_BOOT;
out:
FreePool(target);
return t;
}
static enum boot_target check_loader_entry_one_shot(VOID)
{
EFI_STATUS ret;
CHAR16 *target;
enum boot_target bt;
debug(L"checking %s", LOADER_ENTRY_ONESHOT);
target = get_efi_variable_str(&loader_guid, LOADER_ENTRY_ONESHOT);
del_efi_variable(&loader_guid, LOADER_ENTRY_ONESHOT);
if (!target)
return NORMAL_BOOT;
debug(L"target = %s", target);
bt = name_to_boot_target(target);
if (bt == UNKNOWN_TARGET) {
if (!StrCmp(target, L"dm-verity device corrupted")) {
debug(L"Reboot was triggered by dm-verity module because partition is corrupted");
ret = slot_set_verity_corrupted(TRUE);
if (EFI_ERROR(ret))
efi_perror(ret, L"Failed to set the active slot verity eio flag");
} else
error(L"Unknown oneshot boot target: '%s'", target);
bt = NORMAL_BOOT;
} else if (bt == CHARGER && !get_off_mode_charge()) {
debug(L"Off mode charge is not set, powering off.");
bt = POWER_OFF;
}
FreePool(target);
return bt;
}
static BOOLEAN reset_is_due_to_watchdog_or_panic(void)
{
static enum reset_sources WATCHDOG_RESET_SOURCES[] = {
RESET_KERNEL_WATCHDOG,
RESET_SECURITY_WATCHDOG,
RESET_PMIC_WATCHDOG,
RESET_EC_WATCHDOG
};
enum reset_sources reset_source;
UINTN i;
reset_source = rsci_get_reset_source();
for (i = 0; i < ARRAY_SIZE(WATCHDOG_RESET_SOURCES); i++)
if (reset_source == WATCHDOG_RESET_SOURCES[i]) {
debug(L"Watchdog reset source = %d", reset_source);
return TRUE;
}
return is_reboot_reason(L"kernel_panic") ||
is_reboot_reason(L"watchdog");
}
/* If more than get_watchdog_counter_max() watchdog (or kernel panic)
* resets in a row happened in less than WATCHDOG_DELAY seconds, the
* crash event menu is displayed. This menu informs the user of the
* situation and let him choose which boot target he wants.
*/
static enum boot_target check_watchdog(VOID)
{
EFI_STATUS ret;
UINT8 counter;
EFI_TIME time_ref, now;
if (!get_crash_event_menu())
return NORMAL_BOOT;
ret = get_watchdog_status(&counter, &time_ref);
if (EFI_ERROR(ret)) {
efi_perror(ret, L"Failed to get the watchdog status");
return NORMAL_BOOT;
}
if (!reset_is_due_to_watchdog_or_panic()) {
if (counter != 0) {
ret = reset_watchdog_status();
if (EFI_ERROR(ret)) {
efi_perror(ret, L"Failed to reset the watchdog status");
goto error;
}
}
return NORMAL_BOOT;
}
#ifdef USER
if (is_reboot_reason(L"shutdown")) {
del_reboot_reason();
return POWER_OFF;
}
#endif
ret = uefi_call_wrapper(RT->GetTime, 2, &now, NULL);
if (EFI_ERROR(ret)) {
efi_perror(ret, L"Failed to get the current time");
goto error;
}
if (counter > 0) {
if (efi_time_to_ctime(&now) < efi_time_to_ctime(&time_ref) ||
efi_time_to_ctime(&now) - efi_time_to_ctime(&time_ref) > WATCHDOG_DELAY)
counter = 0;
}
if (counter == 0) {
time_ref = now;
ret = set_watchdog_time_reference(&now);
if (EFI_ERROR(ret)) {
efi_perror(ret, L"Failed to set the watchdog time reference");
goto error;
}
}
counter++;
debug(L"Incrementing watchdog counter (%d)", counter);
if (counter <= get_watchdog_counter_max()) {
ret = set_watchdog_counter(counter);
if (EFI_ERROR(ret))
efi_perror(ret, L"Failed to set the watchdog counter");
goto error;
}
ret = reset_watchdog_status();
if (EFI_ERROR(ret))
efi_perror(ret, L"Failed to reset the watchdog status");
#ifdef USE_UI
return ux_prompt_user_for_boot_target(CRASH_EVENT_CODE);
#else
debug(L"NO_UI,CRASH_EVENT,rebooting");
return NORMAL_BOOT;
#endif
error:
return NORMAL_BOOT;
}
static enum boot_target check_command_line(VOID)
{
UINTN argc, pos;
CHAR16 **argv;
CHAR16 *options;
enum boot_target bt;
bt = NORMAL_BOOT;
if (EFI_ERROR(get_argv(g_loaded_image, &argc, &argv, &options)))
return NORMAL_BOOT;
for (pos = 0; pos < argc; pos++) {
debug(L"Argument %d: %s", pos, argv[pos]);
if (!StrCmp(argv[pos], L"-f")) {
bt = FASTBOOT;
continue;
}
#ifndef USER
if (!StrCmp(argv[pos], L"-U")) {
pos++;
unittest_main(pos >= argc ? NULL : argv[pos]);
FreePool(argv);
return EXIT_SHELL;
}
#endif
if (!StrCmp(argv[pos], L"-a")) {
pos++;
if (pos >= argc) {
error(L"-a requires a memory address");
goto out;
}
/* For compatibility...just ignore the supplied address
* and enter Fastboot mode
*/
bt = FASTBOOT;
continue;
}
/* If we get here the argument isn't recognized */
if (pos == 0) {
/* EFI is inconsistent and only seems to populate the image
* name as argv[0] when called from a shell. Do nothing.
*/
continue;
} else {
error(L"unexpected argument %s", argv[pos]);
goto out;
}
}
out:
FreePool(argv);
FreePool(options);
return bt;
}
static enum boot_target check_battery_inserted(void)
{
enum wake_sources wake_source;
if (!get_off_mode_charge())
return NORMAL_BOOT;
wake_source = rsci_get_wake_source();
if (wake_source == WAKE_BATTERY_INSERTED)
return POWER_OFF;
return NORMAL_BOOT;
}
static enum boot_target check_charge_mode(void)
{
enum wake_sources wake_source;
if (!get_off_mode_charge())
return NORMAL_BOOT;
wake_source = rsci_get_wake_source();
if ((wake_source == WAKE_USB_CHARGER_INSERTED) ||
(wake_source == WAKE_ACDC_CHARGER_INSERTED)) {
debug(L"Wake source = %d", wake_source);
return CHARGER;
}
return NORMAL_BOOT;
}
enum boot_target check_battery(void)
{
if (!get_off_mode_charge())
return NORMAL_BOOT;
if (is_battery_below_boot_OS_threshold()) {
BOOLEAN charger_plugged = is_charger_plugged_in();
debug(L"Battery is below boot OS threshold");
debug(L"Charger is%s plugged", charger_plugged ? L"" : L" not");
return charger_plugged ? CHARGER : POWER_OFF;
}
return NORMAL_BOOT;
}
/* Policy:
* 1. Check if we had multiple watchdog reported in a short period of
* time. If so, let the user choose the boot target.
* 2. Check if the "-a xxxxxxxxx" command line was passed in, if so load an
* android boot image from RAM at that location.
* 3. Check if the fastboot sentinel file \force_fastboot is present, and if
* so, force fastboot mode. Use in bootable media.
* 4. Check for "magic key" being held. Short press loads Recovery. Long press
* loads Fastboot.
* 5. Check if wake source is battery inserted, if so power off
* 6. Check bootloader control block for a boot target, which could be
* the name of a boot image that we know how to read from a partition,
* or a boot image file in the ESP. BCB can specify oneshot or persistent
* targets.
* 7. Check LoaderEntryOneShot for a boot target
* 8. Check if we should go into charge mode or normal boot
*
* target_path - If ESP_EFI_BINARY or ESP_BOOTIMAGE returned, path to the
* image on the EFI System Partition
* oneshot - Whether this is a one-shot boot, indicating that the image at
* target_path should be deleted before chainloading
*
*/
static enum boot_target choose_boot_target(CHAR16 **target_path, BOOLEAN *oneshot)
{
enum boot_target ret;
*target_path = NULL;
*oneshot = TRUE;
#if DEBUG_MESSAGES
print_rsci_values();
#endif
debug(L"Bootlogic: Choosing boot target");
debug(L"Bootlogic: Check osloader command line...");
ret = check_command_line();
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check fastboot sentinel...");
ret = check_fastboot_sentinel();
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check magic key...");
ret = check_magic_key();
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check watchdog...");
ret = check_watchdog();
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check battery insertion...");
ret = check_battery_inserted();
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check BCB...");
ret = check_bcb(target_path, oneshot);
if (ret != NORMAL_BOOT) {
/* clear LOADER_ENTRY_ONESHOT after detecting oneshot from bcb,
* in case of unexpected boot target in next boot. */
if(*oneshot == TRUE)
del_efi_variable(&loader_guid, LOADER_ENTRY_ONESHOT);
else {
/*The bootloader is expected to load and boot into recovery image upon seeting*/
/*boot-fastboot in the BCB command. Recovery the parse the BCB message and*/
/*switches to fastbootd mode*/
if (ret == FASTBOOT)
ret = RECOVERY;
}
goto out;
}
debug(L"Bootlogic: Check reboot target...");
ret = check_loader_entry_one_shot();
if (ret != DNX && ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check battery level...");
ret = check_battery();
#ifdef USE_UI
if (ret == POWER_OFF)
ux_display_low_battery(3);
#else
if (ret == POWER_OFF)
debug(L"NO_UI: low battery");
#endif
if (ret != NORMAL_BOOT)
goto out;
debug(L"Bootlogic: Check charger insertion...");
ret = check_charge_mode();
out:
debug(L"Bootlogic: selected '%s'", boot_target_description(ret));
return ret;
}
#ifdef USE_AVB
/* Disable the slot if kfld failed to load it.
*/
static void disable_slot_if_efi_loaded_slot_failed()
{
UINT8 loaded_slot;
UINT8 slot;
EFI_STATUS ret;
EFI_STATUS err;
UINTN nb_slots;
char **suffixes;
ret = get_efi_loaded_slot(&loaded_slot);
if (EFI_ERROR(ret)) {
/* Just assume loaded slot is active slot if cannot get information
* of loaded slot (whether EFI_NOT_FOUND or 'real' EFI error),
* don't need additional action but print message for 'real' error.
*/
if (ret != EFI_NOT_FOUND)
efi_perror(ret, L"Failed to get loaded slot from efi variable");
return;
}
nb_slots = slot_get_suffixes(&suffixes);
if (loaded_slot >= nb_slots) {
error(L"Invalid slot: %d, nb_slots: %d", (int)loaded_slot, nb_slots);
return;
}
for (slot = 0; slot < nb_slots; ++slot) {
if (slot == loaded_slot)
continue;
ret = get_efi_loaded_slot_failed(slot, &err);
if (EFI_ERROR(ret)) {
/* 1. kfld did not try this slot if EFI_NOT_FOUND.
* 2. Assume kfld did not try this slot if 'real' error happens.
* don't disable slot in both cases but print message for 'real' error.
*/
if (ret != EFI_NOT_FOUND)
efi_perror(ret, L"Failed to call get_efi_loaded_slot_failed");
continue;
}
if (EFI_ERROR(err)) {
/* Disable it if kfld tried this slot but failed. */
debug(L"Disable slot %d because kfld failed to load it",
slot, err);
disable_slot_by_index(slot);
}
}
}
/* Verify if kernelflinger use same slot as kfld and trigger reboot if not.
*
* slot_data - The slot data chosen by Avb flow.
* boot_target - Boot image to load. Values supported are NORMAL_BOOT, RECOVERY,
* and ESP_BOOTIMAGE (for 'fastboot boot')
*/
static void reboot_if_slot_is_different(IN AvbSlotVerifyData *slot_data,
IN enum boot_target boot_target)
{
EFI_STATUS ret;
UINT8 slot;
char *suffix;
UINTN nb_slots;
char **suffixes;
if (slot_data == NULL || slot_data->ab_suffix == NULL)
return;
ret = get_efi_loaded_slot(&slot);
if (EFI_ERROR(ret)) {
/* Just assume loaded slot is active slot if cannot get information
* of loaded slot (whether EFI_NOT_FOUND or 'real' EFI error),
* don't need additional action but print message for 'real' error.
*/
if (ret != EFI_NOT_FOUND)
efi_perror(ret, L"Failed to get loaded slot from efi variable");
return;
}
nb_slots = slot_get_suffixes(&suffixes);
if (slot >= nb_slots) {
error(L"Invalid slot: %d, nb_slots: %d", (int)slot, nb_slots);
return;
}
suffix = suffixes[slot];
if (strcmp((CHAR8 *)slot_data->ab_suffix, suffix)) {
error(L"Avb flow suffix %a doesn't equal to the suffix "
L"in efi variable %a, reboot to target %d",
slot_data->ab_suffix, suffix, boot_target);
reboot_to_target(boot_target, EfiResetCold);
}
}
/* Use AVB load and verify a boot image into RAM.
*
* boot_target - Boot image to load. Values supported are NORMAL_BOOT, RECOVERY,
* and ESP_BOOTIMAGE (for 'fastboot boot')
* target_path - Path to load boot image from for ESP_BOOTIMAGE case, ignored
* otherwise.
* bootimage - Returned allocated pointer value for the loaded boot image.
* oneshot - For ESP_BOOTIMAGE case, flag indicating that the image should
* be deleted.
* boot_state - The boot state, maybe changed according the load and verify result.
*
* Return values:
* EFI_INVALID_PARAMETER - Unsupported boot target type, key is not well-formed,
* or loaded boot image was missing or corrupt
* EFI_ACCESS_DENIED - Validation failed against OEM or embedded certificate,
* boot image still usable
*/
static EFI_STATUS avb_load_verify_boot_image(
IN enum boot_target boot_target,
IN CHAR16 *target_path,
OUT VOID **bootimage,
IN BOOLEAN oneshot,
UINT8 *boot_state,
AvbSlotVerifyData **slot_data)
{
EFI_STATUS ret;
switch (boot_target) {
case NORMAL_BOOT:
case CHARGER:
if (!slot_data) {
ret = EFI_INVALID_PARAMETER;
break;
}
ret = android_image_load_partition_avb_ab("boot", bootimage, boot_state, slot_data);
if (ret == EFI_SUCCESS && *slot_data)
reboot_if_slot_is_different(*slot_data, boot_target);
break;
case RECOVERY:
if (!slot_data) {
ret = EFI_INVALID_PARAMETER;
break;
}
if (recovery_in_boot_partition()) {
ret = avb_load_verify_boot_image(NORMAL_BOOT, target_path, bootimage, oneshot, boot_state, slot_data);
if (ret == EFI_SUCCESS && *slot_data)
reboot_if_slot_is_different(*slot_data, boot_target);
break;
}
ret = android_image_load_partition_avb("recovery", bootimage, boot_state, slot_data);
break;
case ESP_BOOTIMAGE:
/* "fastboot boot" case */
ret = android_image_load_file(g_disk_device, target_path, oneshot,
bootimage);
break;
default:
*bootimage = NULL;
return EFI_INVALID_PARAMETER;
}
if (!EFI_ERROR(ret))
debug(L"boot image loaded");
return ret;
}
#else // USE_AVB == false
/* Validate an image.
*
* Parameters:
* boot_target - Boot image to load. Values supported are NORMAL_BOOT,
* RECOVERY, and ESP_BOOTIMAGE (for 'fastboot boot')
* bootimage - Bootimage to validate
* verifier_cert - Return the certificate that validated the boot image
*
* Return values:
* BOOT_STATE_GREEN - Boot image is valid against provided certificate
* BOOT_STATE_YELLOW - Boot image is valid against embedded certificate
* BOOT_STATE_RED - Boot image is not valid
*/
static UINT8 validate_bootimage(
IN enum boot_target boot_target,
IN VOID *bootimage,
X509 **verifier_cert)
{
CHAR16 target[BOOT_TARGET_SIZE];
CHAR16 *expected;
CHAR16 *expected2 = NULL;
UINT8 boot_state;
boot_state = verify_android_boot_image(bootimage, oem_cert,
oem_cert_size, target,
verifier_cert);
if (boot_state == BOOT_STATE_RED) {
debug(L"boot image doesn't verify");
return boot_state;
}
switch (boot_target) {
case NORMAL_BOOT:
expected = L"/boot";
/* in case of multistage ota */
expected2 = L"/recovery";
break;
case CHARGER:
expected = L"/boot";
break;
case RECOVERY:
if (recovery_in_boot_partition())
expected = L"/boot";
else
expected = L"/recovery";
break;
case ESP_BOOTIMAGE:
/* "live" bootable image */
expected = L"/boot";
break;
default:
expected = NULL;
}
if ((!expected || StrCmp(expected, target)) &&
(!expected2 || StrCmp(expected2, target))) {
debug(L"boot image has unexpected target name");
return BOOT_STATE_RED;
}
return boot_state;
}
/* Load a boot image into RAM.
*
* boot_target - Boot image to load. Values supported are NORMAL_BOOT, RECOVERY,
* and ESP_BOOTIMAGE (for 'fastboot boot')
* target_path - Path to load boot image from for ESP_BOOTIMAGE case, ignored
* otherwise.
* bootimage - Returned allocated pointer value for the loaded boot image.
* oneshot - For ESP_BOOTIMAGE case, flag indicating that the image should
* be deleted.
*
* Return values:
* EFI_INVALID_PARAMETER - Unsupported boot target type, key is not well-formed,
* or loaded boot image was missing or corrupt
* EFI_ACCESS_DENIED - Validation failed against OEM or embedded certificate,
* boot image still usable
*/
static EFI_STATUS load_boot_image(
IN enum boot_target boot_target,
IN CHAR16 *target_path,
OUT VOID **bootimage,
IN BOOLEAN oneshot)
{
EFI_STATUS ret;
switch (boot_target) {
case NORMAL_BOOT:
case CHARGER:
ret = EFI_NOT_FOUND;
if (use_slot() && !slot_get_active())
break;
do {
const CHAR16 *label = slot_label(BOOT_LABEL);
ret = android_image_load_partition(label, bootimage);
if (EFI_ERROR(ret)) {
efi_perror(ret, L"Failed to load boot image from %s partition",
label);
if (use_slot())
slot_boot_failed(boot_target);
}
} while (EFI_ERROR(ret) && slot_get_active());
break;
case RECOVERY:
if (recovery_in_boot_partition()) {
ret = load_boot_image(NORMAL_BOOT, target_path, bootimage, oneshot);
break;
}
if (use_slot() && !slot_recovery_tries_remaining()) {
ret = EFI_NOT_FOUND;
break;
}
ret = android_image_load_partition(RECOVERY_LABEL, bootimage);
break;
case ESP_BOOTIMAGE:
/* "fastboot boot" case */
ret = android_image_load_file(g_disk_device, target_path, oneshot,
bootimage);
break;
default:
*bootimage = NULL;
return EFI_INVALID_PARAMETER;
}
if (!EFI_ERROR(ret))
debug(L"boot image loaded");
return ret;
}
#endif
#define OEMVARS_MAGIC "#OEMVARS\n"
#define OEMVARS_MAGIC_SZ 9
static EFI_STATUS set_image_oemvars_nocheck(VOID *bootimage,
const EFI_GUID *restricted_guid)
{
VOID *oemvars;
UINT32 osz;
EFI_STATUS ret;
ret = get_bootimage_2nd(bootimage, &oemvars, &osz);
if (ret == EFI_SUCCESS && osz > OEMVARS_MAGIC_SZ &&
!memcmp(oemvars, OEMVARS_MAGIC, OEMVARS_MAGIC_SZ)) {
debug(L"secondstage contains raw oemvars");
return flash_oemvars_silent_write_error((CHAR8 *)oemvars + OEMVARS_MAGIC_SZ,
osz - OEMVARS_MAGIC_SZ,
restricted_guid);
}
#ifdef HAL_AUTODETECT
ret = get_bootimage_blob(bootimage, BLOB_TYPE_OEMVARS, &oemvars, &osz);
if (EFI_ERROR(ret)) {
if (ret == EFI_UNSUPPORTED || ret == EFI_NOT_FOUND) {
debug(L"No blobstore in this boot image");
return EFI_SUCCESS;
}
return ret;
}
return flash_oemvars_silent_write_error(oemvars, osz, restricted_guid);
#else
return EFI_NOT_FOUND;
#endif
}
static EFI_STATUS set_image_oemvars(VOID *bootimage)
{
if (!get_oemvars_update()) {
debug(L"OEM vars should be up-to-date");
return EFI_SUCCESS;
}
debug(L"OEM vars may need to be updated");
set_oemvars_update(FALSE);
return set_image_oemvars_nocheck(bootimage, NULL);
}
static EFI_STATUS load_image(VOID *bootimage, UINT8 boot_state,
enum boot_target boot_target,
VBDATA *vb_data
)
{
EFI_STATUS ret;
#ifdef USE_TRUSTY
VOID *tosimage = NULL;
#endif