recovery: Add support to brick a device.
When recovery starts with --brick, it tries to brick the device by
securely wiping all the partitions as listed in /etc/recovery.brick.
This is designed to support bricking lost devices.
Bug: 27253717
Change-Id: Ib0bd4f0a3bdaca4febc91fce6b682e3ec74354e2
(cherry picked from commit 862a4c11190d72851a72a2b97375ec2698078358)
diff --git a/recovery.cpp b/recovery.cpp
index 6b6643f..4688ca6 100644
--- a/recovery.cpp
+++ b/recovery.cpp
@@ -19,7 +19,9 @@
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
+#include <inttypes.h>
#include <limits.h>
+#include <linux/fs.h>
#include <linux/input.h>
#include <stdarg.h>
#include <stdio.h>
@@ -33,12 +35,15 @@
#include <unistd.h>
#include <chrono>
+#include <string>
+#include <vector>
#include <adb.h>
#include <android/log.h> /* Android Log Priority Tags */
#include <android-base/file.h>
#include <android-base/parseint.h>
#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
#include <cutils/android_reboot.h>
#include <cutils/properties.h>
#include <log/logger.h> /* Android Log packet format */
@@ -58,6 +63,7 @@
#include "minzip/DirUtil.h"
#include "roots.h"
#include "ui.h"
+#include "unique_fd.h"
#include "screen_ui.h"
struct selabel_handle *sehandle;
@@ -77,6 +83,7 @@
{ "shutdown_after", no_argument, NULL, 'p' },
{ "reason", required_argument, NULL, 'r' },
{ "security", no_argument, NULL, 'e'},
+ { "brick", no_argument, NULL, 0 },
{ NULL, 0, NULL, 0 },
};
@@ -103,6 +110,7 @@
// So we should check battery with a slightly lower limitation.
static const int BATTERY_OK_PERCENTAGE = 20;
static const int BATTERY_WITH_CHARGER_OK_PERCENTAGE = 15;
+constexpr const char* RECOVERY_BRICK = "/etc/recovery.brick";
RecoveryUI* ui = NULL;
static const char* locale = "en_US";
@@ -853,6 +861,75 @@
return success;
}
+// Secure-wipe a given partition. It uses BLKSECDISCARD, if supported.
+// Otherwise, it goes with BLKDISCARD (if device supports BLKDISCARDZEROES) or
+// BLKZEROOUT.
+static bool secure_wipe_partition(const std::string& partition) {
+ unique_fd fd(TEMP_FAILURE_RETRY(open(partition.c_str(), O_WRONLY)));
+ if (fd.get() == -1) {
+ LOGE("failed to open \"%s\": %s\n", partition.c_str(), strerror(errno));
+ return false;
+ }
+
+ uint64_t range[2] = {0, 0};
+ if (ioctl(fd.get(), BLKGETSIZE64, &range[1]) == -1 || range[1] == 0) {
+ LOGE("failed to get partition size: %s\n", strerror(errno));
+ return false;
+ }
+ printf("Secure-wiping \"%s\" from %" PRIu64 " to %" PRIu64 ".\n",
+ partition.c_str(), range[0], range[1]);
+
+ printf("Trying BLKSECDISCARD...\t");
+ if (ioctl(fd.get(), BLKSECDISCARD, &range) == -1) {
+ printf("failed: %s\n", strerror(errno));
+
+ // Use BLKDISCARD if it zeroes out blocks, otherwise use BLKZEROOUT.
+ unsigned int zeroes;
+ if (ioctl(fd.get(), BLKDISCARDZEROES, &zeroes) == 0 && zeroes != 0) {
+ printf("Trying BLKDISCARD...\t");
+ if (ioctl(fd.get(), BLKDISCARD, &range) == -1) {
+ printf("failed: %s\n", strerror(errno));
+ return false;
+ }
+ } else {
+ printf("Trying BLKZEROOUT...\t");
+ if (ioctl(fd.get(), BLKZEROOUT, &range) == -1) {
+ printf("failed: %s\n", strerror(errno));
+ return false;
+ }
+ }
+ }
+
+ printf("done\n");
+ return true;
+}
+
+// Brick the current device, with a secure wipe of all the partitions in
+// RECOVERY_BRICK.
+static bool brick_device() {
+ ui->SetBackground(RecoveryUI::ERASING);
+ ui->SetProgressType(RecoveryUI::INDETERMINATE);
+
+ std::string partition_list;
+ if (!android::base::ReadFileToString(RECOVERY_BRICK, &partition_list)) {
+ LOGE("failed to read \"%s\".\n", RECOVERY_BRICK);
+ return false;
+ }
+
+ std::vector<std::string> lines = android::base::Split(partition_list, "\n");
+ for (const std::string& line : lines) {
+ std::string partition = android::base::Trim(line);
+ // Ignore '#' comment or empty lines.
+ if (android::base::StartsWith(partition, "#") || partition.empty()) {
+ continue;
+ }
+
+ // Proceed anyway even if it fails to wipe some partition.
+ secure_wipe_partition(partition);
+ }
+ return true;
+}
+
static void choose_recovery_file(Device* device) {
if (!has_cache) {
ui->Print("No /cache partition found.\n");
@@ -1340,6 +1417,7 @@
const char *update_package = NULL;
bool should_wipe_data = false;
bool should_wipe_cache = false;
+ bool should_brick = false;
bool show_text = false;
bool sideload = false;
bool sideload_auto_reboot = false;
@@ -1349,7 +1427,8 @@
bool security_update = false;
int arg;
- while ((arg = getopt_long(argc, argv, "", OPTIONS, NULL)) != -1) {
+ int option_index;
+ while ((arg = getopt_long(argc, argv, "", OPTIONS, &option_index)) != -1) {
switch (arg) {
case 'i': send_intent = optarg; break;
case 'n': android::base::ParseInt(optarg, &retry_count, 0); break;
@@ -1372,6 +1451,13 @@
case 'p': shutdown_after = true; break;
case 'r': reason = optarg; break;
case 'e': security_update = true; break;
+ case 0: {
+ if (strcmp(OPTIONS[option_index].name, "brick") == 0) {
+ should_brick = true;
+ break;
+ }
+ break;
+ }
case '?':
LOGE("Invalid command argument\n");
continue;
@@ -1510,6 +1596,10 @@
if (!wipe_cache(false, device)) {
status = INSTALL_ERROR;
}
+ } else if (should_brick) {
+ if (!brick_device()) {
+ status = INSTALL_ERROR;
+ }
} else if (sideload) {
// 'adb reboot sideload' acts the same as user presses key combinations
// to enter the sideload mode. When 'sideload-auto-reboot' is used, text
