Revert "Revert "Enable verity on userdebug, and add disable-verity to adb""
This reverts commit 99a31b8129b71aeeb08b3c33a39b0f7f97e74852.
Fixed build error, and also fixed memory leak spotted from warning.
(cherry-pick of 96e2e0ea682169fdaea1d5d163c39231a6f7041f.)
Bug: 17691572
Change-Id: I23b5ba537f7b557432041d4338b38b9be434e981
diff --git a/disable_verity_service.c b/disable_verity_service.c
new file mode 100644
index 0000000..ed3da52
--- /dev/null
+++ b/disable_verity_service.c
@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2014 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 "sysdeps.h"
+
+#define TRACE_TAG TRACE_ADB
+#include "adb.h"
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <inttypes.h>
+
+#include "cutils/properties.h"
+#include "ext4_sb.h"
+#include <fs_mgr.h>
+
+#define FSTAB_PREFIX "/fstab."
+struct fstab *fstab;
+
+__attribute__((__format__(printf, 2, 3))) __nonnull((2))
+static void write_console(int fd, const char* format, ...)
+{
+ char buffer[256];
+ va_list args;
+ va_start (args, format);
+ vsnprintf (buffer, sizeof(buffer), format, args);
+ va_end (args);
+
+ adb_write(fd, buffer, strnlen(buffer, sizeof(buffer)));
+}
+
+static int get_target_device_size(int fd, const char *blk_device,
+ uint64_t *device_size)
+{
+ int data_device;
+ struct ext4_super_block sb;
+ struct fs_info info;
+
+ info.len = 0; /* Only len is set to 0 to ask the device for real size. */
+
+ data_device = adb_open(blk_device, O_RDONLY | O_CLOEXEC);
+ if (data_device < 0) {
+ write_console(fd, "Error opening block device (%s)\n", strerror(errno));
+ return -1;
+ }
+
+ if (lseek64(data_device, 1024, SEEK_SET) < 0) {
+ write_console(fd, "Error seeking to superblock\n");
+ adb_close(data_device);
+ return -1;
+ }
+
+ if (adb_read(data_device, &sb, sizeof(sb)) != sizeof(sb)) {
+ write_console(fd, "Error reading superblock\n");
+ adb_close(data_device);
+ return -1;
+ }
+
+ ext4_parse_sb(&sb, &info);
+ *device_size = info.len;
+
+ adb_close(data_device);
+ return 0;
+}
+
+static int disable_verity(int fd, const char *block_device,
+ const char* mount_point)
+{
+ uint32_t magic_number;
+ const uint32_t voff = VERITY_METADATA_MAGIC_DISABLE;
+ uint64_t device_length;
+ int device;
+ int retval = -1;
+
+ device = adb_open(block_device, O_RDWR | O_CLOEXEC);
+ if (device == -1) {
+ write_console(fd, "Could not open block device %s (%s).\n",
+ block_device, strerror(errno));
+ write_console(fd, "Maybe run adb remount?\n");
+ goto errout;
+ }
+
+ // find the start of the verity metadata
+ if (get_target_device_size(fd, (char*)block_device, &device_length) < 0) {
+ write_console(fd, "Could not get target device size.\n");
+ goto errout;
+ }
+
+ if (lseek64(device, device_length, SEEK_SET) < 0) {
+ write_console(fd,
+ "Could not seek to start of verity metadata block.\n");
+ goto errout;
+ }
+
+ // check the magic number
+ if (adb_read(device, &magic_number, sizeof(magic_number))
+ != sizeof(magic_number)) {
+ write_console(fd, "Couldn't read magic number!\n");
+ goto errout;
+ }
+
+ if (magic_number == VERITY_METADATA_MAGIC_DISABLE) {
+ write_console(fd, "Verity already disabled on %s\n", mount_point);
+ goto errout;
+ }
+
+ if (magic_number != VERITY_METADATA_MAGIC_NUMBER) {
+ write_console(fd,
+ "Couldn't find verity metadata at offset %"PRIu64"!\n",
+ device_length);
+ goto errout;
+ }
+
+ if (lseek64(device, device_length, SEEK_SET) < 0) {
+ write_console(fd,
+ "Could not seek to start of verity metadata block.\n");
+ goto errout;
+ }
+
+ if (adb_write(device, &voff, sizeof(voff)) != sizeof(voff)) {
+ write_console(fd, "Could not set verity disabled flag on device %s\n",
+ block_device);
+ goto errout;
+ }
+
+ write_console(fd, "Verity disabled on %s\n", mount_point);
+ retval = 0;
+errout:
+ if (device != -1)
+ adb_close(device);
+ return retval;
+}
+
+void disable_verity_service(int fd, void* cookie)
+{
+#ifdef ALLOW_ADBD_DISABLE_VERITY
+ char fstab_filename[PROPERTY_VALUE_MAX + sizeof(FSTAB_PREFIX)];
+ char propbuf[PROPERTY_VALUE_MAX];
+ int i;
+ bool any_disabled = false;
+
+ property_get("ro.secure", propbuf, "0");
+ if (strcmp(propbuf, "1")) {
+ write_console(fd, "verity not enabled - ENG build\n");
+ goto errout;
+ }
+
+ property_get("ro.debuggable", propbuf, "0");
+ if (strcmp(propbuf, "1")) {
+ write_console(fd, "verity cannot be disabled - USER build\n");
+ goto errout;
+ }
+
+ property_get("ro.hardware", propbuf, "");
+ snprintf(fstab_filename, sizeof(fstab_filename), FSTAB_PREFIX"%s", propbuf);
+
+ fstab = fs_mgr_read_fstab(fstab_filename);
+ if (!fstab) {
+ write_console(fd, "Failed to open %s\nMaybe run adb root?\n",
+ fstab_filename);
+ goto errout;
+ }
+
+ /* Loop through entries looking for ones that vold manages */
+ for (i = 0; i < fstab->num_entries; i++) {
+ if(fs_mgr_is_verified(&fstab->recs[i])) {
+ if (!disable_verity(fd, fstab->recs[i].blk_device,
+ fstab->recs[i].mount_point)) {
+ any_disabled = true;
+ }
+ }
+ }
+
+ if (any_disabled) {
+ write_console(fd,
+ "Now reboot your device for settings to take effect\n");
+ }
+#else
+ write_console(fd, "disable-verity only works for userdebug builds\n");
+#endif
+
+errout:
+ adb_close(fd);
+}