AuthSecret HAL

A security HAL to allow vendor to cryptographically tie components to
the primary user's credential.

Test: AuthSecretHidlTest
Bug: 71527305
Change-Id: I67ebf423dfccb00415d1d79b54e3ded31256cfff
diff --git a/authsecret/1.0/default/Android.bp b/authsecret/1.0/default/Android.bp
new file mode 100644
index 0000000..5c3234f
--- /dev/null
+++ b/authsecret/1.0/default/Android.bp
@@ -0,0 +1,21 @@
+cc_binary {
+    name: "android.hardware.authsecret@1.0-service",
+    init_rc: ["android.hardware.authsecret@1.0-service.rc"],
+    relative_install_path: "hw",
+    vendor: true,
+    srcs: [
+        "service.cpp",
+        "AuthSecret.cpp",
+    ],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "liblog",
+        "libutils",
+        "android.hardware.authsecret@1.0",
+    ],
+}
diff --git a/authsecret/1.0/default/AuthSecret.cpp b/authsecret/1.0/default/AuthSecret.cpp
new file mode 100644
index 0000000..46a3ec1
--- /dev/null
+++ b/authsecret/1.0/default/AuthSecret.cpp
@@ -0,0 +1,47 @@
+#include "AuthSecret.h"
+
+namespace android {
+namespace hardware {
+namespace authsecret {
+namespace V1_0 {
+namespace implementation {
+
+// Methods from ::android::hardware::authsecret::V1_0::IAuthSecret follow.
+Return<void> AuthSecret::primaryUserCredential(const hidl_vec<uint8_t>& secret) {
+    (void)secret;
+
+    // To create a dependency on the credential, it is recommended to derive a
+    // different value from the provided secret for each purpose e.g.
+    //
+    //     purpose1_secret = hash( "purpose1" || secret )
+    //     purpose2_secret = hash( "purpose2" || secret )
+    //
+    // The derived values can then be used as cryptographic keys or stored
+    // securely for comparison in a future call.
+    //
+    // For example, a security module might require that the credential has been
+    // entered before it applies any updates. This can be achieved by storing a
+    // derived value in the module and only applying updates when the same
+    // derived value is presented again.
+    //
+    // This implementation does nothing.
+
+    return Void();
+}
+
+Return<void> AuthSecret::factoryReset() {
+    // Clear all dependency on the secret.
+    //
+    // With the example of updating a security module, the stored value must be
+    // cleared so that the new primary user enrolled as the approver of updates.
+    //
+    // This implementation does nothing as there is no dependence on the secret.
+
+    return Void();
+}
+
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace authsecret
+}  // namespace hardware
+}  // namespace android
diff --git a/authsecret/1.0/default/AuthSecret.h b/authsecret/1.0/default/AuthSecret.h
new file mode 100644
index 0000000..edb49b8
--- /dev/null
+++ b/authsecret/1.0/default/AuthSecret.h
@@ -0,0 +1,36 @@
+#ifndef ANDROID_HARDWARE_AUTHSECRET_V1_0_AUTHSECRET_H
+#define ANDROID_HARDWARE_AUTHSECRET_V1_0_AUTHSECRET_H
+
+#include <android/hardware/authsecret/1.0/IAuthSecret.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+
+namespace android {
+namespace hardware {
+namespace authsecret {
+namespace V1_0 {
+namespace implementation {
+
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_memory;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::sp;
+
+struct AuthSecret : public IAuthSecret {
+    // Methods from ::android::hardware::authsecret::V1_0::IAuthSecret follow.
+    Return<void> primaryUserCredential(const hidl_vec<uint8_t>& secret) override;
+    Return<void> factoryReset() override;
+
+    // Methods from ::android::hidl::base::V1_0::IBase follow.
+};
+
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace authsecret
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_AUTHSECRET_V1_0_AUTHSECRET_H
diff --git a/authsecret/1.0/default/android.hardware.authsecret@1.0-service.rc b/authsecret/1.0/default/android.hardware.authsecret@1.0-service.rc
new file mode 100644
index 0000000..e82da7e
--- /dev/null
+++ b/authsecret/1.0/default/android.hardware.authsecret@1.0-service.rc
@@ -0,0 +1,4 @@
+service vendor.authsecret-1-0 /vendor/bin/hw/android.hardware.authsecret@1.0-service
+    class hal
+    user system
+    group system
diff --git a/authsecret/1.0/default/service.cpp b/authsecret/1.0/default/service.cpp
new file mode 100644
index 0000000..4acd16c
--- /dev/null
+++ b/authsecret/1.0/default/service.cpp
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.1 (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-2.1
+ *
+ * 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.authsecret@1.0-service"
+
+#include <android/hardware/authsecret/1.0/IAuthSecret.h>
+#include <hidl/HidlTransportSupport.h>
+
+#include "AuthSecret.h"
+
+using android::hardware::configureRpcThreadpool;
+using android::hardware::joinRpcThreadpool;
+using android::hardware::authsecret::V1_0::IAuthSecret;
+using android::hardware::authsecret::V1_0::implementation::AuthSecret;
+using android::sp;
+using android::status_t;
+using android::OK;
+
+int main() {
+    configureRpcThreadpool(1, true);
+
+    sp<IAuthSecret> authSecret = new AuthSecret;
+    status_t status = authSecret->registerAsService();
+    LOG_ALWAYS_FATAL_IF(status != OK, "Could not register IAuthSecret");
+
+    joinRpcThreadpool();
+    return 0;
+}