Merge changes from topic "derive-microdroid-vendor-dice-node" into main am: 13db31040f

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2986255

Change-Id: I0a67cf4f1dd6eeea3a3f6ffec3b5320d291dadf6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

init/Android.bp

@@ -463,7 +463,7 @@ cc_binary {
     name: "init_first_stage.microdroid",
     defaults: [
         "avf_build_flags_cc",
-        "init_first_stage_defaults"
+        "init_first_stage_defaults",
     ],
     cflags: ["-DMICRODROID=1"],
     installable: false,

init/block_dev_initializer.cpp

@@ -132,11 +132,19 @@ bool BlockDevInitializer::InitDevices(std::set<std::string> devices) {
 bool BlockDevInitializer::InitDmDevice(const std::string& device) {
     const std::string device_name(basename(device.c_str()));
     const std::string syspath = "/sys/block/" + device_name;
+    return InitDevice(syspath, device_name);
+}
+
+bool BlockDevInitializer::InitPlatformDevice(const std::string& dev_name) {
+    return InitDevice("/sys/devices/platform", dev_name);
+}
+
+bool BlockDevInitializer::InitDevice(const std::string& syspath, const std::string& device_name) {
     bool found = false;
 
-    auto uevent_callback = [&device_name, &device, this, &found](const Uevent& uevent) {
+    auto uevent_callback = [&device_name, this, &found](const Uevent& uevent) {
         if (uevent.device_name == device_name) {
-            LOG(VERBOSE) << "Creating device-mapper device : " << device;
+            LOG(VERBOSE) << "Creating device : " << device_name;
             device_handler_->HandleUevent(uevent);
             found = true;
             return ListenerAction::kStop;
@@ -146,13 +154,13 @@ bool BlockDevInitializer::InitDmDevice(const std::string& device) {
 
     uevent_listener_.RegenerateUeventsForPath(syspath, uevent_callback);
     if (!found) {
-        LOG(INFO) << "dm device '" << device << "' not found in /sys, waiting for its uevent";
+        LOG(INFO) << "device '" << device_name << "' not found in /sys, waiting for its uevent";
         Timer t;
         uevent_listener_.Poll(uevent_callback, 10s);
-        LOG(INFO) << "wait for dm device '" << device << "' returned after " << t;
+        LOG(INFO) << "wait for device '" << device_name << "' returned after " << t;
     }
     if (!found) {
-        LOG(ERROR) << "dm device '" << device << "' not found after polling timeout";
+        LOG(ERROR) << "device '" << device_name << "' not found after polling timeout";
         return false;
     }
     return true;

init/block_dev_initializer.h

@@ -24,6 +24,7 @@
 namespace android {
 namespace init {
 
+// TODO: should this be renamed to FirstStageDevInitialize?
 class BlockDevInitializer final {
   public:
     BlockDevInitializer();
@@ -32,11 +33,13 @@ class BlockDevInitializer final {
     bool InitDmUser(const std::string& name);
     bool InitDevices(std::set<std::string> devices);
     bool InitDmDevice(const std::string& device);
+    bool InitPlatformDevice(const std::string& device);
 
   private:
     ListenerAction HandleUevent(const Uevent& uevent, std::set<std::string>* devices);
 
     bool InitMiscDevice(const std::string& name);
+    bool InitDevice(const std::string& syspath, const std::string& device);
 
     std::unique_ptr<DeviceHandler> device_handler_;
     UeventListener uevent_listener_;

init/first_stage_mount.cpp

@@ -16,6 +16,7 @@
 
 #include "first_stage_mount.h"
 
+#include <signal.h>
 #include <stdlib.h>
 #include <sys/mount.h>
 #include <unistd.h>
@@ -33,6 +34,7 @@
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
+#include <android/avf_cc_flags.h>
 #include <fs_avb/fs_avb.h>
 #include <fs_mgr.h>
 #include <fs_mgr_dm_linear.h>
@@ -272,6 +274,11 @@ bool FirstStageMountVBootV2::DoFirstStageMount() {
     return true;
 }
 
+// TODO: should this be in a library in packages/modules/Virtualization first_stage_init links?
+static bool IsMicrodroidStrictBoot() {
+    return access("/proc/device-tree/chosen/avf,strict-boot", F_OK) == 0;
+}
+
 bool FirstStageMountVBootV2::InitDevices() {
     std::set<std::string> devices;
     GetSuperDeviceName(&devices);
@@ -283,6 +290,14 @@ bool FirstStageMountVBootV2::InitDevices() {
         return false;
     }
 
+    if (IsMicrodroid() && android::virtualization::IsOpenDiceChangesFlagEnabled()) {
+        if (IsMicrodroidStrictBoot()) {
+            if (!block_dev_init_.InitPlatformDevice("open-dice0")) {
+                return false;
+            }
+        }
+    }
+
     if (IsDmLinearEnabled()) {
         auto super_symlink = "/dev/block/by-name/"s + super_partition_name_;
         if (!android::base::Realpath(super_symlink, &super_path_)) {
@@ -527,9 +542,48 @@ bool FirstStageMountVBootV2::TrySwitchSystemAsRoot() {
     return true;
 }
 
+static bool MaybeDeriveMicrodroidVendorDiceNode(Fstab* fstab) {
+    std::optional<std::string> microdroid_vendor_block_dev;
+    for (auto entry = fstab->begin(); entry != fstab->end(); entry++) {
+        if (entry->mount_point == "/vendor") {
+            microdroid_vendor_block_dev.emplace(entry->blk_device);
+            break;
+        }
+    }
+    if (!microdroid_vendor_block_dev.has_value()) {
+        LOG(VERBOSE) << "No microdroid vendor partition to mount";
+        return true;
+    }
+    // clang-format off
+    const std::array<const char*, 7> args = {
+        "/system/bin/derive_microdroid_vendor_dice_node",
+                "--dice-driver", "/dev/open-dice0",
+                "--microdroid-vendor-disk-image", microdroid_vendor_block_dev->data(),
+                "--output", "/microdroid_resources/dice_chain.raw",
+    };
+    // clang-format-on
+    // ForkExecveAndWaitForCompletion calls waitpid to wait for the fork-ed process to finish.
+    // The first_stage_console adds SA_NOCLDWAIT flag to the SIGCHLD handler, which means that
+    // waitpid will always return -ECHLD. Here we re-register a default handler, so that waitpid
+    // works.
+    LOG(INFO) << "Deriving dice node for microdroid vendor partition";
+    signal(SIGCHLD, SIG_DFL);
+    if (!ForkExecveAndWaitForCompletion(args[0], (char**)args.data())) {
+        LOG(ERROR) << "Failed to derive microdroid vendor dice node";
+        return false;
+    }
+    return true;
+}
+
 bool FirstStageMountVBootV2::MountPartitions() {
     if (!TrySwitchSystemAsRoot()) return false;
 
+    if (IsMicrodroid() && android::virtualization::IsOpenDiceChangesFlagEnabled()) {
+        if (!MaybeDeriveMicrodroidVendorDiceNode(&fstab_)) {
+            return false;
+        }
+    }
+
     if (!SkipMountingPartitions(&fstab_, true /* verbose */)) return false;
 
     for (auto current = fstab_.begin(); current != fstab_.end();) {