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.
diff --git a/recovery.c b/recovery.c
index 4385307..58c84ef 100644
--- a/recovery.c
+++ b/recovery.c
@@ -37,12 +37,15 @@
#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 },
};
@@ -63,6 +66,7 @@
* --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).
@@ -107,6 +111,26 @@
* 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;
@@ -209,8 +233,7 @@
}
static void
-set_sdcard_update_bootloader_message()
-{
+set_sdcard_update_bootloader_message() {
struct bootloader_message boot;
memset(&boot, 0, sizeof(boot));
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
@@ -223,8 +246,7 @@
// 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)
-{
+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");
@@ -255,7 +277,7 @@
check_and_fclose(log, LOG_FILE);
}
- // Reset the bootloader message to revert to a normal main system boot.
+ // Reset to mormal system boot so recovery won't cycle indefinitely.
struct bootloader_message boot;
memset(&boot, 0, sizeof(boot));
set_bootloader_message(&boot);
@@ -272,8 +294,7 @@
}
static int
-erase_root(const char *root)
-{
+erase_root(const char *root) {
ui_set_background(BACKGROUND_ICON_INSTALLING);
ui_show_indeterminate_progress();
ui_print("Formatting %s...\n", root);
@@ -384,8 +405,7 @@
}
static void
-prompt_and_wait()
-{
+prompt_and_wait() {
char** headers = prepend_title(MENU_HEADERS);
for (;;) {
@@ -438,14 +458,12 @@
}
static void
-print_property(const char *key, const char *name, void *cookie)
-{
+print_property(const char *key, const char *name, void *cookie) {
fprintf(stderr, "%s=%s\n", key, name);
}
int
-main(int argc, char **argv)
-{
+main(int argc, char **argv) {
time_t start = time(NULL);
// If these fail, there's not really anywhere to complain...
@@ -459,7 +477,10 @@
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) {
@@ -469,6 +490,7 @@
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;
@@ -486,7 +508,42 @@
int status = INSTALL_SUCCESS;
- if (update_package != NULL) {
+ 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) {