Merge changes from topic "adb_root_in_user"

am: da1251d6a5

Change-Id: Ia9959008ac5cc571efe46bd0b80cbae53356d5ed

adb/Android.bp

@@ -24,7 +24,8 @@ cc_defaults {
         "-Wno-missing-field-initializers",
         "-Wthread-safety",
         "-Wvla",
-        "-DADB_HOST=1", // overridden by adbd_defaults
+        "-DADB_HOST=1",         // overridden by adbd_defaults
+        "-DALLOW_ADBD_ROOT=0",  // overridden by adbd_defaults
     ],
     cpp_std: "experimental",
 
@@ -79,7 +80,8 @@ cc_defaults {
     product_variables: {
         debuggable: {
             cflags: [
-                "-DALLOW_ADBD_ROOT",
+                "-UALLOW_ADBD_ROOT",
+                "-DALLOW_ADBD_ROOT=1",
                 "-DALLOW_ADBD_DISABLE_VERITY",
                 "-DALLOW_ADBD_NO_AUTH",
             ],

adb/daemon/main.cpp

@@ -58,17 +58,23 @@
 #if defined(__ANDROID__)
 static const char* root_seclabel = nullptr;
 
+static inline bool is_device_unlocked() {
+    return "orange" == android::base::GetProperty("ro.boot.verifiedbootstate", "");
+}
+
 static bool should_drop_capabilities_bounding_set() {
-#if defined(ALLOW_ADBD_ROOT)
-    if (__android_log_is_debuggable()) {
-        return false;
+    if (ALLOW_ADBD_ROOT || is_device_unlocked()) {
+        if (__android_log_is_debuggable()) {
+            return false;
+        }
     }
-#endif
     return true;
 }
 
 static bool should_drop_privileges() {
-#if defined(ALLOW_ADBD_ROOT)
+    // "adb root" not allowed, always drop privileges.
+    if (!ALLOW_ADBD_ROOT && !is_device_unlocked()) return true;
+
     // The properties that affect `adb root` and `adb unroot` are ro.secure and
     // ro.debuggable. In this context the names don't make the expected behavior
     // particularly obvious.
@@ -98,9 +104,6 @@ static bool should_drop_privileges() {
     }
 
     return drop;
-#else
-    return true; // "adb root" not allowed, always drop privileges.
-#endif // ALLOW_ADBD_ROOT
 }
 
 static void drop_privileges(int server_port) {
@@ -205,6 +208,10 @@ int adbd_main(int server_port) {
 #if defined(ALLOW_ADBD_NO_AUTH)
     // If ro.adb.secure is unset, default to no authentication required.
     auth_required = android::base::GetBoolProperty("ro.adb.secure", false);
+#elif defined(__ANDROID__)
+    if (is_device_unlocked()) {  // allows no authentication when the device is unlocked.
+        auth_required = android::base::GetBoolProperty("ro.adb.secure", false);
+    }
 #endif
 
     adbd_auth_init();

init/first_stage_init.cpp

@@ -199,6 +199,12 @@ int FirstStageMain(int argc, char** argv) {
         SwitchRoot("/first_stage_ramdisk");
     }
 
+    // If this file is present, the second-stage init will use a userdebug sepolicy
+    // and load adb_debug.prop to allow adb root, if the device is unlocked.
+    if (access("/force_debuggable", F_OK) == 0) {
+        setenv("INIT_FORCE_DEBUGGABLE", "true", 1);
+    }
+
     if (!DoFirstStageMount()) {
         LOG(FATAL) << "Failed to mount required partitions early ...";
     }

init/init.cpp

@@ -39,6 +39,7 @@
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <cutils/android_reboot.h>
+#include <fs_avb/fs_avb.h>
 #include <fs_mgr_vendor_overlay.h>
 #include <keyutils.h>
 #include <libavb/libavb.h>
@@ -74,6 +75,7 @@ using android::base::ReadFileToString;
 using android::base::StringPrintf;
 using android::base::Timer;
 using android::base::Trim;
+using android::fs_mgr::AvbHandle;
 
 namespace android {
 namespace init {
@@ -92,6 +94,7 @@ static std::string wait_prop_value;
 static bool shutting_down;
 static std::string shutdown_command;
 static bool do_shutdown = false;
+static bool load_debug_prop = false;
 
 std::vector<std::string> late_import_paths;
 
@@ -655,10 +658,17 @@ int SecondStageMain(int argc, char** argv) {
     const char* avb_version = getenv("INIT_AVB_VERSION");
     if (avb_version) property_set("ro.boot.avb_version", avb_version);
 
+    // See if need to load debug props to allow adb root, when the device is unlocked.
+    const char* force_debuggable_env = getenv("INIT_FORCE_DEBUGGABLE");
+    if (force_debuggable_env && AvbHandle::IsDeviceUnlocked()) {
+        load_debug_prop = "true"s == force_debuggable_env;
+    }
+
     // Clean up our environment.
     unsetenv("INIT_STARTED_AT");
     unsetenv("INIT_SELINUX_TOOK");
     unsetenv("INIT_AVB_VERSION");
+    unsetenv("INIT_FORCE_DEBUGGABLE");
 
     // Now set up SELinux for second stage.
     SelinuxSetupKernelLogging();
@@ -672,7 +682,7 @@ int SecondStageMain(int argc, char** argv) {
 
     InstallSignalFdHandler(&epoll);
 
-    property_load_boot_defaults();
+    property_load_boot_defaults(load_debug_prop);
     fs_mgr_vendor_overlay_mount_all();
     export_oem_lock_status();
     StartPropertyService(&epoll);

init/property_service.cpp

@@ -866,7 +866,7 @@ static void property_derive_build_fingerprint() {
     }
 }
 
-void property_load_boot_defaults() {
+void property_load_boot_defaults(bool load_debug_prop) {
     // TODO(b/117892318): merge prop.default and build.prop files into one
     // We read the properties and their values into a map, in order to always allow properties
     // loaded in the later property files to override the properties in loaded in the earlier
@@ -888,6 +888,12 @@ void property_load_boot_defaults() {
     load_properties_from_file("/product_services/build.prop", nullptr, &properties);
     load_properties_from_file("/factory/factory.prop", "ro.*", &properties);
 
+    if (load_debug_prop) {
+        constexpr static const char kAdbDebugProp[] = "/system/etc/adb_debug.prop";
+        LOG(INFO) << "Loading " << kAdbDebugProp;
+        load_properties_from_file(kAdbDebugProp, nullptr, &properties);
+    }
+
     for (const auto& [name, value] : properties) {
         std::string error;
         if (PropertySet(name, value, &error) != PROP_SUCCESS) {

init/property_service.h

@@ -36,7 +36,7 @@ uint32_t HandlePropertySet(const std::string& name, const std::string& value,
 extern bool PropertyChildReap(pid_t pid);
 
 void property_init(void);
-void property_load_boot_defaults(void);
+void property_load_boot_defaults(bool);
 void load_persist_props(void);
 void load_system_props(void);
 void StartPropertyService(Epoll* epoll);

init/selinux.cpp

@@ -61,14 +61,18 @@
 #include <android-base/parseint.h>
 #include <android-base/unique_fd.h>
 #include <cutils/android_reboot.h>
+#include <fs_avb/fs_avb.h>
 #include <selinux/android.h>
 
 #include "reboot_utils.h"
 #include "util.h"
 
+using namespace std::string_literals;
+
 using android::base::ParseInt;
 using android::base::Timer;
 using android::base::unique_fd;
+using android::fs_mgr::AvbHandle;
 
 namespace android {
 namespace init {
@@ -267,6 +271,8 @@ bool GetVendorMappingVersion(std::string* plat_vers) {
 }
 
 constexpr const char plat_policy_cil_file[] = "/system/etc/selinux/plat_sepolicy.cil";
+constexpr const char userdebug_plat_policy_cil_file[] =
+        "/system/etc/selinux/userdebug_plat_sepolicy.cil";
 
 bool IsSplitPolicyDevice() {
     return access(plat_policy_cil_file, R_OK) != -1;
@@ -282,10 +288,21 @@ bool LoadSplitPolicy() {
     // secilc is invoked to compile the above three policy files into a single monolithic policy
     // file. This file is then loaded into the kernel.
 
+    // See if we need to load userdebug_plat_sepolicy.cil instead of plat_sepolicy.cil.
+    const char* force_debuggable_env = getenv("INIT_FORCE_DEBUGGABLE");
+    bool use_userdebug_policy =
+            ((force_debuggable_env && "true"s == force_debuggable_env) &&
+             AvbHandle::IsDeviceUnlocked() && access(userdebug_plat_policy_cil_file, F_OK) == 0);
+    if (use_userdebug_policy) {
+        LOG(WARNING) << "Using userdebug system sepolicy";
+    }
+
     // Load precompiled policy from vendor image, if a matching policy is found there. The policy
     // must match the platform policy on the system image.
     std::string precompiled_sepolicy_file;
-    if (FindPrecompiledSplitPolicy(&precompiled_sepolicy_file)) {
+    // use_userdebug_policy requires compiling sepolicy with userdebug_plat_sepolicy.cil.
+    // Thus it cannot use the precompiled policy from vendor image.
+    if (!use_userdebug_policy && FindPrecompiledSplitPolicy(&precompiled_sepolicy_file)) {
         unique_fd fd(open(precompiled_sepolicy_file.c_str(), O_RDONLY | O_CLOEXEC | O_BINARY));
         if (fd != -1) {
             if (selinux_android_load_policy_from_fd(fd, precompiled_sepolicy_file.c_str()) < 0) {
@@ -358,7 +375,7 @@ bool LoadSplitPolicy() {
     // clang-format off
     std::vector<const char*> compile_args {
         "/system/bin/secilc",
-        plat_policy_cil_file,
+        use_userdebug_policy ? userdebug_plat_policy_cil_file : plat_policy_cil_file,
         "-m", "-M", "true", "-G", "-N",
         // Target the highest policy language version supported by the kernel
         "-c", version_as_string.c_str(),