Add microdroid-specialized KeyMint service

KeyMint in microdroid will initially be a specialized version of the
software KeyMint reference implementation. Begin this specialization by
removing the services that aren't needed within VMs.

Bug: 190578423
Test: atest MicrodroidHostTestCases
Change-Id: I6eee95944ccc555656868dad193f29b83ebf46a4
diff --git a/microdroid/Android.bp b/microdroid/Android.bp
index 55d1eae..0add9c3 100644
--- a/microdroid/Android.bp
+++ b/microdroid/Android.bp
@@ -158,7 +158,7 @@
     name: "microdroid_vendor",
     use_avb: true,
     deps: [
-        "android.hardware.security.keymint-service",
+        "android.hardware.security.keymint-service.microdroid",
         "microdroid_fstab",
         "microdroid_precompiled_sepolicy",
         "microdroid_precompiled_sepolicy.plat_sepolicy_and_mapping.sha256",
diff --git a/microdroid/init.rc b/microdroid/init.rc
index 4410b82..b683230 100644
--- a/microdroid/init.rc
+++ b/microdroid/init.rc
@@ -101,7 +101,7 @@
     start keystore2
 
 on late-fs
-    start vendor.keymint-default
+    start vendor.keymint-microdroid
 
     # TODO(b/185767624): change the hard-coded size?
     mount tmpfs tmpfs /data noatime nosuid nodev rw size=128M
diff --git a/microdroid/keymint/Android.bp b/microdroid/keymint/Android.bp
new file mode 100644
index 0000000..5867900
--- /dev/null
+++ b/microdroid/keymint/Android.bp
@@ -0,0 +1,32 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+cc_binary {
+    name: "android.hardware.security.keymint-service.microdroid",
+    relative_install_path: "hw",
+    init_rc: ["android.hardware.security.keymint-service.microdroid.rc"],
+    vintf_fragments: [
+        "android.hardware.security.keymint-service.microdroid.xml",
+    ],
+    vendor: true,
+    cflags: [
+        "-Wall",
+        "-Wextra",
+    ],
+    shared_libs: [
+        "android.hardware.security.keymint-V1-ndk_platform",
+        "libbase",
+        "libbinder_ndk",
+        "libcppbor_external",
+        "libcrypto",
+        "libkeymaster_portable",
+        "libkeymint",
+        "liblog",
+        "libpuresoftkeymasterdevice",
+        "libutils",
+    ],
+    srcs: [
+        "service.cpp",
+    ],
+}
diff --git a/microdroid/keymint/android.hardware.security.keymint-service.microdroid.rc b/microdroid/keymint/android.hardware.security.keymint-service.microdroid.rc
new file mode 100644
index 0000000..d6851bd
--- /dev/null
+++ b/microdroid/keymint/android.hardware.security.keymint-service.microdroid.rc
@@ -0,0 +1,3 @@
+service vendor.keymint-microdroid /vendor/bin/hw/android.hardware.security.keymint-service.microdroid
+    class early_hal
+    user nobody
diff --git a/microdroid/keymint/android.hardware.security.keymint-service.microdroid.xml b/microdroid/keymint/android.hardware.security.keymint-service.microdroid.xml
new file mode 100644
index 0000000..73d15a8
--- /dev/null
+++ b/microdroid/keymint/android.hardware.security.keymint-service.microdroid.xml
@@ -0,0 +1,6 @@
+<manifest version="1.0" type="device">
+    <hal format="aidl">
+        <name>android.hardware.security.keymint</name>
+        <fqname>IKeyMintDevice/default</fqname>
+    </hal>
+</manifest>
diff --git a/microdroid/keymint/service.cpp b/microdroid/keymint/service.cpp
new file mode 100644
index 0000000..d2b75a1
--- /dev/null
+++ b/microdroid/keymint/service.cpp
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2021, 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 LOG_TAG "android.hardware.security.keymint-service"
+
+#include <AndroidKeyMintDevice.h>
+#include <android-base/logging.h>
+#include <android/binder_manager.h>
+#include <android/binder_process.h>
+#include <keymaster/soft_keymaster_logger.h>
+
+using aidl::android::hardware::security::keymint::AndroidKeyMintDevice;
+using aidl::android::hardware::security::keymint::SecurityLevel;
+
+template <typename T, class... Args>
+std::shared_ptr<T> addService(Args&&... args) {
+    std::shared_ptr<T> ser = ndk::SharedRefBase::make<T>(std::forward<Args>(args)...);
+    auto instanceName = std::string(T::descriptor) + "/default";
+    LOG(INFO) << "adding keymint service instance: " << instanceName;
+    binder_status_t status =
+            AServiceManager_addService(ser->asBinder().get(), instanceName.c_str());
+    CHECK(status == STATUS_OK);
+    return ser;
+}
+
+int main() {
+    // Zero threads seems like a useless pool, but below we'll join this thread to it, increasing
+    // the pool size to 1.
+    ABinderProcess_setThreadPoolMaxThreadCount(0);
+    // Add Keymint Service
+    std::shared_ptr<AndroidKeyMintDevice> keyMint =
+            addService<AndroidKeyMintDevice>(SecurityLevel::SOFTWARE);
+
+    // VMs cannot implement the Secure Clock Service
+    // addService<AndroidSecureClock>(keyMint);
+
+    // VMs don't need to implement the Shared Secret Service as the host
+    // facilities the establishment of the shared secret.
+    // addService<AndroidSharedSecret>(keyMint);
+
+    // VMs don't implement the Remotely Provisioned Component Service as the
+    // host facilities provisioning.
+    // addService<AndroidRemotelyProvisionedComponentDevice>(keyMint);
+
+    ABinderProcess_joinThreadPool();
+    return EXIT_FAILURE; // should not reach
+}
diff --git a/microdroid/microdroid_compatibility_matrix.xml b/microdroid/microdroid_compatibility_matrix.xml
index 7293d22..dbc12a8 100644
--- a/microdroid/microdroid_compatibility_matrix.xml
+++ b/microdroid/microdroid_compatibility_matrix.xml
@@ -6,30 +6,6 @@
         <interface>
             <name>IKeyMintDevice</name>
             <instance>default</instance>
-            <instance>strongbox</instance>
-        </interface>
-    </hal>
-    <hal format="aidl" optional="true">
-        <name>android.hardware.security.keymint</name>
-        <interface>
-            <name>IRemotelyProvisionedComponent</name>
-            <instance>default</instance>
-        </interface>
-    </hal>
-    <hal format="aidl" optional="true">
-        <name>android.hardware.security.secureclock</name>
-        <version>1</version>
-        <interface>
-            <name>ISecureClock</name>
-            <instance>default</instance>
-        </interface>
-    </hal>
-    <hal format="aidl" optional="true">
-        <name>android.hardware.security.sharedsecret</name>
-        <version>1</version>
-        <interface>
-            <name>ISharedSecret</name>
-            <instance>default</instance>
         </interface>
     </hal>
 </compatibility-matrix>
diff --git a/microdroid/sepolicy/vendor/file_contexts b/microdroid/sepolicy/vendor/file_contexts
index 71b4fcd..0aa85cf 100644
--- a/microdroid/sepolicy/vendor/file_contexts
+++ b/microdroid/sepolicy/vendor/file_contexts
@@ -35,4 +35,4 @@
 
 /bin/install-recovery\.sh u:object_r:vendor_install_recovery_exec:s0
 
-/bin/hw/android\.hardware\.security\.keymint-service u:object_r:hal_keymint_default_exec:s0
+/bin/hw/android\.hardware\.security\.keymint-service\.microdroid u:object_r:hal_keymint_default_exec:s0