android_bootable_recovery/recovery.c
Oscar Montemayor 0523156775 Recovery changes for Encrypted File Systems.
This change enables/disables the Encrypted file systems feature. It reads some properties form the data partition, wipes the partition out, and then rewrites the proper properties again into the data partition to signal that encrypted FS are enabled.
2009-12-10 14:49:04 -08:00

574 lines
20 KiB
C

/*
* Copyright (C) 2007 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 <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <linux/input.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/reboot.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include "bootloader.h"
#include "common.h"
#include "cutils/properties.h"
#include "firmware.h"
#include "install.h"
#include "minui/minui.h"
#include "minzip/DirUtil.h"
#include "roots.h"
#include "recovery_ui.h"
#include "efs_migration.h"
static const struct option OPTIONS[] = {
{ "send_intent", required_argument, NULL, 's' },
{ "update_package", required_argument, NULL, 'u' },
{ "wipe_data", no_argument, NULL, 'w' },
{ "wipe_cache", no_argument, NULL, 'c' },
// TODO{oam}: implement improved command line passing key, egnot to review.
{ "set_encrypted_filesystem", required_argument, NULL, 'e' },
{ NULL, 0, NULL, 0 },
};
static const char *COMMAND_FILE = "CACHE:recovery/command";
static const char *INTENT_FILE = "CACHE:recovery/intent";
static const char *LOG_FILE = "CACHE:recovery/log";
static const char *SDCARD_PACKAGE_FILE = "SDCARD:update.zip";
static const char *TEMPORARY_LOG_FILE = "/tmp/recovery.log";
/*
* The recovery tool communicates with the main system through /cache files.
* /cache/recovery/command - INPUT - command line for tool, one arg per line
* /cache/recovery/log - OUTPUT - combined log file from recovery run(s)
* /cache/recovery/intent - OUTPUT - intent that was passed in
*
* The arguments which may be supplied in the recovery.command file:
* --send_intent=anystring - write the text out to recovery.intent
* --update_package=root:path - verify install an OTA package file
* --wipe_data - erase user data (and cache), then reboot
* --wipe_cache - wipe cache (but not user data), then reboot
* --set_encrypted_filesystem=on|off - enables / diasables encrypted fs
*
* After completing, we remove /cache/recovery/command and reboot.
* Arguments may also be supplied in the bootloader control block (BCB).
* These important scenarios must be safely restartable at any point:
*
* FACTORY RESET
* 1. user selects "factory reset"
* 2. main system writes "--wipe_data" to /cache/recovery/command
* 3. main system reboots into recovery
* 4. get_args() writes BCB with "boot-recovery" and "--wipe_data"
* -- after this, rebooting will restart the erase --
* 5. erase_root() reformats /data
* 6. erase_root() reformats /cache
* 7. finish_recovery() erases BCB
* -- after this, rebooting will restart the main system --
* 8. main() calls reboot() to boot main system
*
* OTA INSTALL
* 1. main system downloads OTA package to /cache/some-filename.zip
* 2. main system writes "--update_package=CACHE:some-filename.zip"
* 3. main system reboots into recovery
* 4. get_args() writes BCB with "boot-recovery" and "--update_package=..."
* -- after this, rebooting will attempt to reinstall the update --
* 5. install_package() attempts to install the update
* NOTE: the package install must itself be restartable from any point
* 6. finish_recovery() erases BCB
* -- after this, rebooting will (try to) restart the main system --
* 7. ** if install failed **
* 7a. prompt_and_wait() shows an error icon and waits for the user
* 7b; the user reboots (pulling the battery, etc) into the main system
* 8. main() calls maybe_install_firmware_update()
* ** if the update contained radio/hboot firmware **:
* 8a. m_i_f_u() writes BCB with "boot-recovery" and "--wipe_cache"
* -- after this, rebooting will reformat cache & restart main system --
* 8b. m_i_f_u() writes firmware image into raw cache partition
* 8c. m_i_f_u() writes BCB with "update-radio/hboot" and "--wipe_cache"
* -- after this, rebooting will attempt to reinstall firmware --
* 8d. bootloader tries to flash firmware
* 8e. bootloader writes BCB with "boot-recovery" (keeping "--wipe_cache")
* -- after this, rebooting will reformat cache & restart main system --
* 8f. erase_root() reformats /cache
* 8g. finish_recovery() erases BCB
* -- after this, rebooting will (try to) restart the main system --
* 9. main() calls reboot() to boot main system
*
* ENCRYPTED FILE SYSTEMS ENABLE/DISABLE
* 1. user selects "enable encrypted file systems"
* 2. main system writes "--set_encrypted_filesystem=on|off" to
* /cache/recovery/command
* 3. main system reboots into recovery
* 4. get_args() writes BCB with "boot-recovery" and
* "--set_encrypted_filesystems=on|off"
* -- after this, rebooting will restart the transition --
* 5. read_encrypted_fs_info() retrieves encrypted file systems settings from /data
* Settings include: property to specify the Encrypted FS istatus and
* FS encryption key if enabled (not yet implemented)
* 6. erase_root() reformats /data
* 7. erase_root() reformats /cache
* 8. restore_encrypted_fs_info() writes required encrypted file systems settings to /data
* Settings include: property to specify the Encrypted FS status and
* FS encryption key if enabled (not yet implemented)
* 9. finish_recovery() erases BCB
* -- after this, rebooting will restart the main system --
* 10. main() calls reboot() to boot main system
*/
static const int MAX_ARG_LENGTH = 4096;
static const int MAX_ARGS = 100;
// open a file given in root:path format, mounting partitions as necessary
static FILE*
fopen_root_path(const char *root_path, const char *mode) {
if (ensure_root_path_mounted(root_path) != 0) {
LOGE("Can't mount %s\n", root_path);
return NULL;
}
char path[PATH_MAX] = "";
if (translate_root_path(root_path, path, sizeof(path)) == NULL) {
LOGE("Bad path %s\n", root_path);
return NULL;
}
// When writing, try to create the containing directory, if necessary.
// Use generous permissions, the system (init.rc) will reset them.
if (strchr("wa", mode[0])) dirCreateHierarchy(path, 0777, NULL, 1);
FILE *fp = fopen(path, mode);
return fp;
}
// close a file, log an error if the error indicator is set
static void
check_and_fclose(FILE *fp, const char *name) {
fflush(fp);
if (ferror(fp)) LOGE("Error in %s\n(%s)\n", name, strerror(errno));
fclose(fp);
}
// command line args come from, in decreasing precedence:
// - the actual command line
// - the bootloader control block (one per line, after "recovery")
// - the contents of COMMAND_FILE (one per line)
static void
get_args(int *argc, char ***argv) {
struct bootloader_message boot;
memset(&boot, 0, sizeof(boot));
get_bootloader_message(&boot); // this may fail, leaving a zeroed structure
if (boot.command[0] != 0 && boot.command[0] != 255) {
LOGI("Boot command: %.*s\n", sizeof(boot.command), boot.command);
}
if (boot.status[0] != 0 && boot.status[0] != 255) {
LOGI("Boot status: %.*s\n", sizeof(boot.status), boot.status);
}
// --- if arguments weren't supplied, look in the bootloader control block
if (*argc <= 1) {
boot.recovery[sizeof(boot.recovery) - 1] = '\0'; // Ensure termination
const char *arg = strtok(boot.recovery, "\n");
if (arg != NULL && !strcmp(arg, "recovery")) {
*argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
(*argv)[0] = strdup(arg);
for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
if ((arg = strtok(NULL, "\n")) == NULL) break;
(*argv)[*argc] = strdup(arg);
}
LOGI("Got arguments from boot message\n");
} else if (boot.recovery[0] != 0 && boot.recovery[0] != 255) {
LOGE("Bad boot message\n\"%.20s\"\n", boot.recovery);
}
}
// --- if that doesn't work, try the command file
if (*argc <= 1) {
FILE *fp = fopen_root_path(COMMAND_FILE, "r");
if (fp != NULL) {
char *argv0 = (*argv)[0];
*argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
(*argv)[0] = argv0; // use the same program name
char buf[MAX_ARG_LENGTH];
for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
if (!fgets(buf, sizeof(buf), fp)) break;
(*argv)[*argc] = strdup(strtok(buf, "\r\n")); // Strip newline.
}
check_and_fclose(fp, COMMAND_FILE);
LOGI("Got arguments from %s\n", COMMAND_FILE);
}
}
// --> write the arguments we have back into the bootloader control block
// always boot into recovery after this (until finish_recovery() is called)
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
int i;
for (i = 1; i < *argc; ++i) {
strlcat(boot.recovery, (*argv)[i], sizeof(boot.recovery));
strlcat(boot.recovery, "\n", sizeof(boot.recovery));
}
set_bootloader_message(&boot);
}
static void
set_sdcard_update_bootloader_message() {
struct bootloader_message boot;
memset(&boot, 0, sizeof(boot));
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
set_bootloader_message(&boot);
}
// clear the recovery command and prepare to boot a (hopefully working) system,
// copy our log file to cache as well (for the system to read), and
// record any intent we were asked to communicate back to the system.
// this function is idempotent: call it as many times as you like.
static void
finish_recovery(const char *send_intent) {
// By this point, we're ready to return to the main system...
if (send_intent != NULL) {
FILE *fp = fopen_root_path(INTENT_FILE, "w");
if (fp == NULL) {
LOGE("Can't open %s\n", INTENT_FILE);
} else {
fputs(send_intent, fp);
check_and_fclose(fp, INTENT_FILE);
}
}
// Copy logs to cache so the system can find out what happened.
FILE *log = fopen_root_path(LOG_FILE, "a");
if (log == NULL) {
LOGE("Can't open %s\n", LOG_FILE);
} else {
FILE *tmplog = fopen(TEMPORARY_LOG_FILE, "r");
if (tmplog == NULL) {
LOGE("Can't open %s\n", TEMPORARY_LOG_FILE);
} else {
static long tmplog_offset = 0;
fseek(tmplog, tmplog_offset, SEEK_SET); // Since last write
char buf[4096];
while (fgets(buf, sizeof(buf), tmplog)) fputs(buf, log);
tmplog_offset = ftell(tmplog);
check_and_fclose(tmplog, TEMPORARY_LOG_FILE);
}
check_and_fclose(log, LOG_FILE);
}
// Reset to mormal system boot so recovery won't cycle indefinitely.
struct bootloader_message boot;
memset(&boot, 0, sizeof(boot));
set_bootloader_message(&boot);
// Remove the command file, so recovery won't repeat indefinitely.
char path[PATH_MAX] = "";
if (ensure_root_path_mounted(COMMAND_FILE) != 0 ||
translate_root_path(COMMAND_FILE, path, sizeof(path)) == NULL ||
(unlink(path) && errno != ENOENT)) {
LOGW("Can't unlink %s\n", COMMAND_FILE);
}
sync(); // For good measure.
}
static int
erase_root(const char *root) {
ui_set_background(BACKGROUND_ICON_INSTALLING);
ui_show_indeterminate_progress();
ui_print("Formatting %s...\n", root);
return format_root_device(root);
}
static char**
prepend_title(char** headers) {
char* title[] = { "Android system recovery <"
EXPAND(RECOVERY_API_VERSION) "e>",
"",
NULL };
// count the number of lines in our title, plus the
// caller-provided headers.
int count = 0;
char** p;
for (p = title; *p; ++p, ++count);
for (p = headers; *p; ++p, ++count);
char** new_headers = malloc((count+1) * sizeof(char*));
char** h = new_headers;
for (p = title; *p; ++p, ++h) *h = *p;
for (p = headers; *p; ++p, ++h) *h = *p;
*h = NULL;
return new_headers;
}
static int
get_menu_selection(char** headers, char** items, int menu_only) {
// throw away keys pressed previously, so user doesn't
// accidentally trigger menu items.
ui_clear_key_queue();
ui_start_menu(headers, items);
int selected = 0;
int chosen_item = -1;
while (chosen_item < 0) {
int key = ui_wait_key();
int visible = ui_text_visible();
int action = device_handle_key(key, visible);
if (action < 0) {
switch (action) {
case HIGHLIGHT_UP:
--selected;
selected = ui_menu_select(selected);
break;
case HIGHLIGHT_DOWN:
++selected;
selected = ui_menu_select(selected);
break;
case SELECT_ITEM:
chosen_item = selected;
break;
case NO_ACTION:
break;
}
} else if (!menu_only) {
chosen_item = action;
}
}
ui_end_menu();
return chosen_item;
}
static void
wipe_data(int confirm) {
if (confirm) {
static char** title_headers = NULL;
if (title_headers == NULL) {
char* headers[] = { "Confirm wipe of all user data?",
" THIS CAN NOT BE UNDONE.",
"",
NULL };
title_headers = prepend_title(headers);
}
char* items[] = { " No",
" No",
" No",
" No",
" No",
" No",
" No",
" Yes -- delete all user data", // [7]
" No",
" No",
" No",
NULL };
int chosen_item = get_menu_selection(title_headers, items, 1);
if (chosen_item != 7) {
return;
}
}
ui_print("\n-- Wiping data...\n");
device_wipe_data();
erase_root("DATA:");
erase_root("CACHE:");
ui_print("Data wipe complete.\n");
}
static void
prompt_and_wait() {
char** headers = prepend_title(MENU_HEADERS);
for (;;) {
finish_recovery(NULL);
ui_reset_progress();
int chosen_item = get_menu_selection(headers, MENU_ITEMS, 0);
// device-specific code may take some action here. It may
// return one of the core actions handled in the switch
// statement below.
chosen_item = device_perform_action(chosen_item);
switch (chosen_item) {
case ITEM_REBOOT:
return;
case ITEM_WIPE_DATA:
wipe_data(ui_text_visible());
if (!ui_text_visible()) return;
break;
case ITEM_WIPE_CACHE:
ui_print("\n-- Wiping cache...\n");
erase_root("CACHE:");
ui_print("Cache wipe complete.\n");
if (!ui_text_visible()) return;
break;
case ITEM_APPLY_SDCARD:
ui_print("\n-- Install from sdcard...\n");
set_sdcard_update_bootloader_message();
int status = install_package(SDCARD_PACKAGE_FILE);
if (status != INSTALL_SUCCESS) {
ui_set_background(BACKGROUND_ICON_ERROR);
ui_print("Installation aborted.\n");
} else if (!ui_text_visible()) {
return; // reboot if logs aren't visible
} else {
if (firmware_update_pending()) {
ui_print("\nReboot via menu to complete\n"
"installation.\n");
} else {
ui_print("\nInstall from sdcard complete.\n");
}
}
break;
}
}
}
static void
print_property(const char *key, const char *name, void *cookie) {
fprintf(stderr, "%s=%s\n", key, name);
}
int
main(int argc, char **argv) {
time_t start = time(NULL);
// If these fail, there's not really anywhere to complain...
freopen(TEMPORARY_LOG_FILE, "a", stdout); setbuf(stdout, NULL);
freopen(TEMPORARY_LOG_FILE, "a", stderr); setbuf(stderr, NULL);
fprintf(stderr, "Starting recovery on %s", ctime(&start));
ui_init();
get_args(&argc, &argv);
int previous_runs = 0;
const char *send_intent = NULL;
const char *update_package = NULL;
const char *efs_mode = NULL;
int wipe_data = 0, wipe_cache = 0;
int toggle_efs = 0;
encrypted_fs_info efs_data;
int arg;
while ((arg = getopt_long(argc, argv, "", OPTIONS, NULL)) != -1) {
switch (arg) {
case 'p': previous_runs = atoi(optarg); break;
case 's': send_intent = optarg; break;
case 'u': update_package = optarg; break;
case 'w': wipe_data = wipe_cache = 1; break;
case 'c': wipe_cache = 1; break;
case 'e': efs_mode = optarg; toggle_efs = 1; break;
case '?':
LOGE("Invalid command argument\n");
continue;
}
}
fprintf(stderr, "Command:");
for (arg = 0; arg < argc; arg++) {
fprintf(stderr, " \"%s\"", argv[arg]);
}
fprintf(stderr, "\n\n");
property_list(print_property, NULL);
fprintf(stderr, "\n");
int status = INSTALL_SUCCESS;
if (toggle_efs) {
if (strcmp(efs_mode,"on") == 0) {
efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_ENABLED;
ui_print("Enabling Encrypted FS.\n");
} else if (strcmp(efs_mode,"off") == 0) {
efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_DISABLED;
ui_print("Disabling Encrypted FS.\n");
} else {
ui_print("Error: invalid Encrypted FS setting.\n");
status = INSTALL_ERROR;
}
// Recovery strategy: if the data partition is damaged, disable encrypted file systems.
// This preventsthe device recycling endlessly in recovery mode.
// TODO{oam}: implement improved recovery strategy later. egnor to review.
if (read_encrypted_fs_info(&efs_data)) {
ui_print("Encrypted FS change aborted, resetting to disabled state.\n");
efs_data.encrypted_fs_mode = MODE_ENCRYPTEDFS_DISABLED;
}
if (status != INSTALL_ERROR) {
if (erase_root("DATA:")) {
ui_print("Data wipe failed.\n");
status = INSTALL_ERROR;
} else if (erase_root("CACHE:")) {
ui_print("Cache wipe failed.\n");
status = INSTALL_ERROR;
} else if (restore_encrypted_fs_info(&efs_data)) {
ui_print("Encrypted FS change aborted.\n");
status = INSTALL_ERROR;
} else {
ui_print("Successfully updated Encrypted FS.\n");
status = INSTALL_SUCCESS;
}
}
} else if (update_package != NULL) {
status = install_package(update_package);
if (status != INSTALL_SUCCESS) ui_print("Installation aborted.\n");
} else if (wipe_data) {
if (device_wipe_data()) status = INSTALL_ERROR;
if (erase_root("DATA:")) status = INSTALL_ERROR;
if (wipe_cache && erase_root("CACHE:")) status = INSTALL_ERROR;
if (status != INSTALL_SUCCESS) ui_print("Data wipe failed.\n");
} else if (wipe_cache) {
if (wipe_cache && erase_root("CACHE:")) status = INSTALL_ERROR;
if (status != INSTALL_SUCCESS) ui_print("Cache wipe failed.\n");
} else {
status = INSTALL_ERROR; // No command specified
}
if (status != INSTALL_SUCCESS) ui_set_background(BACKGROUND_ICON_ERROR);
if (status != INSTALL_SUCCESS || ui_text_visible()) prompt_and_wait();
// If there is a radio image pending, reboot now to install it.
maybe_install_firmware_update(send_intent);
// Otherwise, get ready to boot the main system...
finish_recovery(send_intent);
ui_print("Rebooting...\n");
sync();
reboot(RB_AUTOBOOT);
return EXIT_SUCCESS;
}