Move enable-verity/disable-verity out of adb to a helper binary.

Test: adb enable-verity
Test: adb disable-verity
Test: adb shell enable-verity
Test: adb shell disable-verity
Test: fs_mgr/tests/adb-remount-test.sh
Change-Id: I0f21a6678b332cc9166d912aa38952d50d924566
diff --git a/adb/Android.bp b/adb/Android.bp
index bf71919..d79a97f 100644
--- a/adb/Android.bp
+++ b/adb/Android.bp
@@ -430,16 +430,10 @@
                 "daemon/mdns.cpp",
                 "daemon/reboot_service.cpp",
                 "daemon/restart_service.cpp",
-                "daemon/set_verity_enable_state_service.cpp",
-            ],
-            static_libs: [
-                "libavb_user",
             ],
             shared_libs: [
                 "libbootloader_message",
                 "libmdnssd",
-                "libfec",
-                "libfs_mgr",
                 "libselinux",
             ],
         },
@@ -517,6 +511,7 @@
     name: "adbd_system_binaries",
     required: [
         "abb",
+        "set-verity-state",
     ]
 }
 
diff --git a/adb/daemon/services.cpp b/adb/daemon/services.cpp
index 181a8c5..e38bb00 100644
--- a/adb/daemon/services.cpp
+++ b/adb/daemon/services.cpp
@@ -55,7 +55,6 @@
 #include "daemon/framebuffer_service.h"
 #include "daemon/reboot_service.h"
 #include "daemon/restart_service.h"
-#include "daemon/set_verity_enable_state_service.h"
 #include "daemon/shell_service.h"
 
 
@@ -269,11 +268,11 @@
         return StartSubprocess("/system/bin/bu restore", nullptr, SubprocessType::kRaw,
                                SubprocessProtocol::kNone);
     } else if (name.starts_with("disable-verity:")) {
-        return create_service_thread("verity-on", std::bind(set_verity_enabled_state_service,
-                                                            std::placeholders::_1, false));
+        return StartSubprocess("/system/bin/disable-verity", nullptr, SubprocessType::kRaw,
+                               SubprocessProtocol::kNone);
     } else if (name.starts_with("enable-verity:")) {
-        return create_service_thread("verity-off", std::bind(set_verity_enabled_state_service,
-                                                             std::placeholders::_1, true));
+        return StartSubprocess("/system/bin/enable-verity", nullptr, SubprocessType::kRaw,
+                               SubprocessProtocol::kNone);
     } else if (android::base::ConsumePrefix(&name, "tcpip:")) {
         std::string str(name);
 
diff --git a/adb/daemon/set_verity_enable_state_service.cpp b/adb/daemon/set_verity_enable_state_service.cpp
deleted file mode 100644
index 4fbccdb..0000000
--- a/adb/daemon/set_verity_enable_state_service.cpp
+++ /dev/null
@@ -1,250 +0,0 @@
-/*
- * 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.
- */
-
-#define TRACE_TAG ADB
-
-#include "set_verity_enable_state_service.h"
-#include "sysdeps.h"
-
-#include <errno.h>
-#include <fcntl.h>
-#include <inttypes.h>
-#include <libavb_user/libavb_user.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <sys/mount.h>
-#include <sys/stat.h>
-
-#include <android-base/properties.h>
-#include <android-base/stringprintf.h>
-#include <fs_mgr.h>
-#include <fs_mgr_overlayfs.h>
-#include <fstab/fstab.h>
-#include <log/log_properties.h>
-
-#include "adb.h"
-#include "adb_io.h"
-#include "adb_unique_fd.h"
-
-#include "fec/io.h"
-
-#ifdef ALLOW_ADBD_DISABLE_VERITY
-static const bool kAllowDisableVerity = true;
-#else
-static const bool kAllowDisableVerity = false;
-#endif
-
-void suggest_run_adb_root(int fd) {
-    if (getuid() != 0) WriteFdExactly(fd, "Maybe run adb root?\n");
-}
-
-static bool make_block_device_writable(const std::string& dev) {
-    unique_fd fd(unix_open(dev, O_RDONLY | O_CLOEXEC));
-    if (fd == -1) {
-        return false;
-    }
-
-    int OFF = 0;
-    bool result = (ioctl(fd.get(), BLKROSET, &OFF) != -1);
-    return result;
-}
-
-/* Turn verity on/off */
-static bool set_verity_enabled_state(int fd, const char* block_device, const char* mount_point,
-                                     bool enable) {
-    if (!make_block_device_writable(block_device)) {
-        WriteFdFmt(fd, "Could not make block device %s writable (%s).\n",
-                   block_device, strerror(errno));
-        return false;
-    }
-
-    fec::io fh(block_device, O_RDWR);
-
-    if (!fh) {
-        WriteFdFmt(fd, "Could not open block device %s (%s).\n", block_device, strerror(errno));
-        suggest_run_adb_root(fd);
-        return false;
-    }
-
-    fec_verity_metadata metadata;
-
-    if (!fh.get_verity_metadata(metadata)) {
-        WriteFdExactly(fd, "Couldn't find verity metadata!\n");
-        return false;
-    }
-
-    if (!enable && metadata.disabled) {
-        WriteFdFmt(fd, "Verity already disabled on %s\n", mount_point);
-        return false;
-    }
-
-    if (enable && !metadata.disabled) {
-        WriteFdFmt(fd, "Verity already enabled on %s\n", mount_point);
-        return false;
-    }
-
-    if (!fh.set_verity_status(enable)) {
-        WriteFdFmt(fd, "Could not set verity %s flag on device %s with error %s\n",
-                   enable ? "enabled" : "disabled",
-                   block_device, strerror(errno));
-        return false;
-    }
-
-    auto change = false;
-    errno = 0;
-    if (enable ? fs_mgr_overlayfs_teardown(mount_point, &change)
-               : fs_mgr_overlayfs_setup(nullptr, mount_point, &change)) {
-        if (change) {
-            WriteFdFmt(fd, "%s overlayfs for %s\n", enable ? "disabling" : "using", mount_point);
-        }
-    } else if (errno) {
-        int expected_errno = enable ? EBUSY : ENOENT;
-        if (errno != expected_errno) {
-            WriteFdFmt(fd, "Overlayfs %s for %s failed with error %s\n",
-                       enable ? "teardown" : "setup", mount_point, strerror(errno));
-        }
-    }
-    WriteFdFmt(fd, "Verity %s on %s\n", enable ? "enabled" : "disabled", mount_point);
-    return true;
-}
-
-/* Helper function to get A/B suffix, if any. If the device isn't
- * using A/B the empty string is returned. Otherwise either "_a",
- * "_b", ... is returned.
- */
-static std::string get_ab_suffix() {
-    return android::base::GetProperty("ro.boot.slot_suffix", "");
-}
-
-static bool is_avb_device_locked() {
-    return android::base::GetProperty("ro.boot.vbmeta.device_state", "") == "locked";
-}
-
-static bool overlayfs_setup(int fd, bool enable) {
-    auto change = false;
-    errno = 0;
-    if (enable ? fs_mgr_overlayfs_teardown(nullptr, &change)
-               : fs_mgr_overlayfs_setup(nullptr, nullptr, &change)) {
-        if (change) {
-            WriteFdFmt(fd, "%s overlayfs\n", enable ? "disabling" : "using");
-        }
-    } else if (errno) {
-        WriteFdFmt(fd, "Overlayfs %s failed with error %s\n", enable ? "teardown" : "setup",
-                   strerror(errno));
-        suggest_run_adb_root(fd);
-    }
-    return change;
-}
-
-/* Use AVB to turn verity on/off */
-static bool set_avb_verity_enabled_state(int fd, AvbOps* ops, bool enable_verity) {
-    std::string ab_suffix = get_ab_suffix();
-    bool verity_enabled;
-
-    if (is_avb_device_locked()) {
-        WriteFdExactly(fd, "Device is locked. Please unlock the device first\n");
-        return false;
-    }
-
-    if (!avb_user_verity_get(ops, ab_suffix.c_str(), &verity_enabled)) {
-        WriteFdExactly(fd, "Error getting verity state. Try adb root first?\n");
-        return false;
-    }
-
-    if ((verity_enabled && enable_verity) || (!verity_enabled && !enable_verity)) {
-        WriteFdFmt(fd, "verity is already %s\n", verity_enabled ? "enabled" : "disabled");
-        return false;
-    }
-
-    if (!avb_user_verity_set(ops, ab_suffix.c_str(), enable_verity)) {
-        WriteFdExactly(fd, "Error setting verity\n");
-        return false;
-    }
-
-    overlayfs_setup(fd, enable_verity);
-    WriteFdFmt(fd, "Successfully %s verity\n", enable_verity ? "enabled" : "disabled");
-    return true;
-}
-
-void set_verity_enabled_state_service(unique_fd fd, bool enable) {
-    bool any_changed = false;
-
-    // Figure out if we're using VB1.0 or VB2.0 (aka AVB) - by
-    // contract, androidboot.vbmeta.digest is set by the bootloader
-    // when using AVB).
-    bool using_avb = !android::base::GetProperty("ro.boot.vbmeta.digest", "").empty();
-
-    // If using AVB, dm-verity is used on any build so we want it to
-    // be possible to disable/enable on any build (except USER). For
-    // VB1.0 dm-verity is only enabled on certain builds.
-    if (!using_avb) {
-        if (!kAllowDisableVerity) {
-            WriteFdFmt(fd.get(), "%s-verity only works for userdebug builds\n",
-                       enable ? "enable" : "disable");
-        }
-
-        if (!android::base::GetBoolProperty("ro.secure", false)) {
-            overlayfs_setup(fd.get(), enable);
-            WriteFdExactly(fd.get(), "verity not enabled - ENG build\n");
-            return;
-        }
-    }
-
-    // Should never be possible to disable dm-verity on a USER build
-    // regardless of using AVB or VB1.0.
-    if (!__android_log_is_debuggable()) {
-        WriteFdExactly(fd.get(), "verity cannot be disabled/enabled - USER build\n");
-        return;
-    }
-
-    if (using_avb) {
-        // Yep, the system is using AVB.
-        AvbOps* ops = avb_ops_user_new();
-        if (ops == nullptr) {
-            WriteFdExactly(fd.get(), "Error getting AVB ops\n");
-            return;
-        }
-        if (set_avb_verity_enabled_state(fd.get(), ops, enable)) {
-            any_changed = true;
-        }
-        avb_ops_user_free(ops);
-    } else {
-        // Not using AVB - assume VB1.0.
-
-        // read all fstab entries at once from all sources
-        android::fs_mgr::Fstab fstab;
-        if (!android::fs_mgr::ReadDefaultFstab(&fstab)) {
-            WriteFdExactly(fd.get(), "Failed to read fstab\n");
-            suggest_run_adb_root(fd.get());
-            return;
-        }
-
-        // Loop through entries looking for ones that verity manages.
-        for (const auto& entry : fstab) {
-            if (entry.fs_mgr_flags.verify) {
-                if (set_verity_enabled_state(fd.get(), entry.blk_device.c_str(),
-                                             entry.mount_point.c_str(), enable)) {
-                    any_changed = true;
-                }
-            }
-        }
-    }
-    if (!any_changed) any_changed = overlayfs_setup(fd.get(), enable);
-
-    if (any_changed) {
-        WriteFdExactly(fd.get(), "Now reboot your device for settings to take effect\n");
-    }
-}
diff --git a/adb/daemon/set_verity_enable_state_service.h b/adb/daemon/set_verity_enable_state_service.h
deleted file mode 100644
index c0ed98e..0000000
--- a/adb/daemon/set_verity_enable_state_service.h
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * Copyright (C) 2018 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.
- */
-
-#pragma once
-
-#include "adb_unique_fd.h"
-
-#if defined(__ANDROID__)
-void set_verity_enabled_state_service(unique_fd fd, bool enable);
-#endif