Reinstate C++ KeyMint impl as default

This is a partial revert of aosp/2856649, changeID
Ia450e9a8f2dc530f79e8d74d7ce65f7d67ea129f, because it turns out
that there are Wear devices that are using the default implementation
(but which are not covered by TreeHugger/presubmit).

It restores the C++ implementation for KeyMint as
android.hardware.security.keymint-service, but preserves the Rust
libraries that were moved here in that CL as a subsequent CL
(aosp/2852598) means that Cuttlefish now uses the libraries here.

Test: VtsAidlKeyMintTargetTest on Cuttlefish
Bug: 328251011
Bug: 314513765
Change-Id: Id6f3491144588e418cd6e18e51262fe839bfdf39

security/keymint/aidl/default/Android.bp

@@ -7,9 +7,48 @@ package {
     default_applicable_licenses: ["hardware_interfaces_license"],
 }
 
-rust_binary {
+cc_binary {
     name: "android.hardware.security.keymint-service",
     relative_install_path: "hw",
+    init_rc: ["android.hardware.security.keymint-service.rc"],
+    vintf_fragments: [
+        "android.hardware.security.keymint-service.xml",
+        "android.hardware.security.sharedsecret-service.xml",
+        "android.hardware.security.secureclock-service.xml",
+    ],
+    vendor: true,
+    cflags: [
+        "-Wall",
+        "-Wextra",
+    ],
+    defaults: [
+        "keymint_use_latest_hal_aidl_ndk_shared",
+    ],
+    shared_libs: [
+        "android.hardware.security.rkp-V3-ndk",
+        "android.hardware.security.sharedsecret-V1-ndk",
+        "android.hardware.security.secureclock-V1-ndk",
+        "libbase",
+        "libbinder_ndk",
+        "libcppbor_external",
+        "libcrypto",
+        "libkeymaster_portable",
+        "libkeymint",
+        "liblog",
+        "libpuresoftkeymasterdevice",
+        "libutils",
+    ],
+    srcs: [
+        "service.cpp",
+    ],
+    required: [
+        "android.hardware.hardware_keystore.xml",
+    ],
+}
+
+rust_binary {
+    name: "android.hardware.security.keymint-service.nonsecure",
+    relative_install_path: "hw",
     vendor: true,
     init_rc: ["android.hardware.security.keymint-service.rc"],
     vintf_fragments: [

security/keymint/aidl/default/service.cpp

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2020, 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 <android-base/logging.h>
+#include <android/binder_manager.h>
+#include <android/binder_process.h>
+
+#include <AndroidKeyMintDevice.h>
+#include <AndroidRemotelyProvisionedComponentDevice.h>
+#include <AndroidSecureClock.h>
+#include <AndroidSharedSecret.h>
+#include <keymaster/soft_keymaster_logger.h>
+
+using aidl::android::hardware::security::keymint::AndroidKeyMintDevice;
+using aidl::android::hardware::security::keymint::AndroidRemotelyProvisionedComponentDevice;
+using aidl::android::hardware::security::keymint::SecurityLevel;
+using aidl::android::hardware::security::secureclock::AndroidSecureClock;
+using aidl::android::hardware::security::sharedsecret::AndroidSharedSecret;
+
+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_EQ(status, STATUS_OK);
+    return ser;
+}
+
+int main() {
+    // The global logger object required by keymaster's logging macros in keymaster/logger.h.
+    keymaster::SoftKeymasterLogger km_logger;
+    // 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);
+    // Add Secure Clock Service
+    addService<AndroidSecureClock>(keyMint);
+    // Add Shared Secret Service
+    addService<AndroidSharedSecret>(keyMint);
+    // Add Remotely Provisioned Component Service
+    addService<AndroidRemotelyProvisionedComponentDevice>(keyMint);
+    ABinderProcess_joinThreadPool();
+    return EXIT_FAILURE;  // should not reach
+}