Secretkeeper implementation: in-HAL/nonsecure impl

Create the default/reference implementation of Secretkeeper HAL. Status
quo, this is non-secure implementation. In reality, the HAL should be
backed by a privileged component such a trusted app.

Bug: 291224769
Test: Topic includes VTS
Change-Id: I6a4ad50482d537f5438de6201275f4020cd827df
diff --git a/compatibility_matrices/compatibility_matrix.9.xml b/compatibility_matrices/compatibility_matrix.9.xml
index 83d2665..9f6b78b 100644
--- a/compatibility_matrices/compatibility_matrix.9.xml
+++ b/compatibility_matrices/compatibility_matrix.9.xml
@@ -302,6 +302,14 @@
             <instance>default</instance>
         </interface>
     </hal>
+    <hal format="aidl" optional="true">
+        <name>android.hardware.security.secretkeeper</name>
+        <version>1</version>
+        <interface>
+            <name>ISecretkeeper</name>
+            <instance>nonsecure</instance>
+        </interface>
+    </hal>
     <hal format="aidl" optional="true" updatable-via-apex="true">
         <name>android.hardware.security.keymint</name>
         <version>1-3</version>
diff --git a/security/secretkeeper/default/Android.bp b/security/secretkeeper/default/Android.bp
new file mode 100644
index 0000000..1c39fa6
--- /dev/null
+++ b/security/secretkeeper/default/Android.bp
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+rust_binary {
+    name: "android.hardware.security.secretkeeper-service.nonsecure",
+    relative_install_path: "hw",
+    vendor: true,
+    init_rc: ["secretkeeper.rc"],
+    vintf_fragments: ["secretkeeper.xml"],
+    rustlibs: [
+        "android.hardware.security.secretkeeper-V1-rust",
+        "libandroid_logger",
+        "libbinder_rs",
+        "liblog_rust",
+        "libsecretkeeper_comm_nostd",
+    ],
+    srcs: [
+        "src/main.rs",
+    ],
+}
diff --git a/security/secretkeeper/default/secretkeeper.rc b/security/secretkeeper/default/secretkeeper.rc
new file mode 100644
index 0000000..f39f9b7
--- /dev/null
+++ b/security/secretkeeper/default/secretkeeper.rc
@@ -0,0 +1,5 @@
+service vendor.secretkeeper /vendor/bin/hw/android.hardware.security.secretkeeper-service.nonsecure
+    interface aidl android.hardware.security.secretkeeper.ISecretkeeper/nonsecure
+    class hal
+    user nobody
+    group nobody
diff --git a/security/secretkeeper/default/secretkeeper.xml b/security/secretkeeper/default/secretkeeper.xml
new file mode 100644
index 0000000..40aebe0
--- /dev/null
+++ b/security/secretkeeper/default/secretkeeper.xml
@@ -0,0 +1,28 @@
+<manifest version="1.0" type="device">
+<!--
+/*
+** Copyright 2022, 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.
+*/
+-->
+
+    <hal format="aidl">
+        <name>android.hardware.security.secretkeeper</name>
+        <version>1</version>
+        <interface>
+            <name>ISecretkeeper</name>
+            <instance>nonsecure</instance>
+        </interface>
+    </hal>
+</manifest>
diff --git a/security/secretkeeper/default/src/main.rs b/security/secretkeeper/default/src/main.rs
new file mode 100644
index 0000000..2d367c5
--- /dev/null
+++ b/security/secretkeeper/default/src/main.rs
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2023 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.
+ */
+
+use binder::{BinderFeatures, Interface};
+use log::{error, info, Level};
+use secretkeeper_comm::data_types::error::SecretkeeperError;
+use secretkeeper_comm::data_types::packet::{RequestPacket, ResponsePacket};
+use secretkeeper_comm::data_types::request::Request;
+use secretkeeper_comm::data_types::request_response_impl::{
+    GetVersionRequest, GetVersionResponse, Opcode,
+};
+use secretkeeper_comm::data_types::response::Response;
+
+use android_hardware_security_secretkeeper::aidl::android::hardware::security::secretkeeper::ISecretkeeper::{
+    BnSecretkeeper, BpSecretkeeper, ISecretkeeper,
+};
+
+const CURRENT_VERSION: u64 = 1;
+
+#[derive(Debug, Default)]
+pub struct NonSecureSecretkeeper;
+
+impl Interface for NonSecureSecretkeeper {}
+
+impl ISecretkeeper for NonSecureSecretkeeper {
+    fn processSecretManagementRequest(&self, request: &[u8]) -> binder::Result<Vec<u8>> {
+        Ok(self.process_opaque_request(request))
+    }
+}
+
+impl NonSecureSecretkeeper {
+    // A set of requests to Secretkeeper are 'opaque' - encrypted bytes with inner structure
+    // described by CDDL. They need to be decrypted, deserialized and processed accordingly.
+    fn process_opaque_request(&self, request: &[u8]) -> Vec<u8> {
+        // TODO(b/291224769) The request will need to be decrypted & response need to be encrypted
+        // with key & related artifacts pre-shared via Authgraph Key Exchange HAL.
+        self.process_opaque_request_unhandled_error(request)
+            .unwrap_or_else(
+                // SecretkeeperError is also a valid 'Response', serialize to a response packet.
+                |sk_err| {
+                    Response::serialize_to_packet(&sk_err)
+                        .into_bytes()
+                        .expect("Panicking due to serialization failing")
+                },
+            )
+    }
+
+    fn process_opaque_request_unhandled_error(
+        &self,
+        request: &[u8],
+    ) -> Result<Vec<u8>, SecretkeeperError> {
+        let request_packet = RequestPacket::from_bytes(request).map_err(|e| {
+            error!("Failed to get Request packet from bytes: {:?}", e);
+            SecretkeeperError::RequestMalformed
+        })?;
+        let response_packet = match request_packet
+            .opcode()
+            .map_err(|_| SecretkeeperError::RequestMalformed)?
+        {
+            Opcode::GetVersion => Self::process_get_version_request(request_packet)?,
+            _ => todo!("TODO(b/291224769): Unimplemented operations"),
+        };
+
+        response_packet
+            .into_bytes()
+            .map_err(|_| SecretkeeperError::UnexpectedServerError)
+    }
+
+    fn process_get_version_request(
+        request: RequestPacket,
+    ) -> Result<ResponsePacket, SecretkeeperError> {
+        // Deserialization really just verifies the structural integrity of the request such
+        // as args being empty.
+        let _request = GetVersionRequest::deserialize_from_packet(request)
+            .map_err(|_| SecretkeeperError::RequestMalformed)?;
+        let response = GetVersionResponse::new(CURRENT_VERSION);
+        Ok(response.serialize_to_packet())
+    }
+}
+
+fn main() {
+    // Initialize Android logging.
+    android_logger::init_once(
+        android_logger::Config::default()
+            .with_tag("NonSecureSecretkeeper")
+            .with_min_level(Level::Info)
+            .with_log_id(android_logger::LogId::System),
+    );
+    // Redirect panic messages to logcat.
+    std::panic::set_hook(Box::new(|panic_info| {
+        error!("{}", panic_info);
+    }));
+
+    let service = NonSecureSecretkeeper::default();
+    let service_binder = BnSecretkeeper::new_binder(service, BinderFeatures::default());
+    let service_name = format!(
+        "{}/nonsecure",
+        <BpSecretkeeper as ISecretkeeper>::get_descriptor()
+    );
+    binder::add_service(&service_name, service_binder.as_binder()).unwrap_or_else(|e| {
+        panic!(
+            "Failed to register service {} because of {:?}.",
+            service_name, e
+        );
+    });
+    info!("Registered Binder service, joining threadpool.");
+    binder::ProcessState::join_thread_pool();
+}