Revert "Remove android.security.remoteprovisioning interfaces"

This reverts commit 9fad346811d81cac9fdfec1aee012a2f1b973344.

Reason for revert: DroidMonitor-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=git_udc-d1-dev-plus-aosp-without-vendor&target=errorprone&lkgb=9769185&lkbb=9776170&fkbb=9771476, bug b/274209879

Change-Id: I210c4a47d76864c3c212b907eb875ef363c3beab
diff --git a/keystore2/aidl/Android.bp b/keystore2/aidl/Android.bp
index 8f5c13b..e3961da 100644
--- a/keystore2/aidl/Android.bp
+++ b/keystore2/aidl/Android.bp
@@ -103,6 +103,28 @@
 }
 
 aidl_interface {
+    name: "android.security.remoteprovisioning",
+    srcs: [ "android/security/remoteprovisioning/*.aidl" ],
+    imports: [
+        "android.hardware.security.keymint-V3",
+        "android.hardware.security.rkp-V3",
+    ],
+    unstable: true,
+    backend: {
+        java: {
+            platform_apis: true,
+        },
+        ndk: {
+            enabled: true,
+            apps_enabled: false,
+        },
+        rust: {
+            enabled: true,
+        },
+    },
+}
+
+aidl_interface {
     name: "android.security.maintenance",
     srcs: [ "android/security/maintenance/*.aidl" ],
     imports: [
diff --git a/keystore2/aidl/android/security/remoteprovisioning/AttestationPoolStatus.aidl b/keystore2/aidl/android/security/remoteprovisioning/AttestationPoolStatus.aidl
new file mode 100644
index 0000000..3528b42
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/AttestationPoolStatus.aidl
@@ -0,0 +1,45 @@
+/*
+ * 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.
+ */
+
+package android.security.remoteprovisioning;
+
+/**
+ * This parcelable provides information about the state of the attestation key pool.
+ * @hide
+ */
+parcelable AttestationPoolStatus {
+    /**
+     * The number of signed attestation certificate chains which will expire when the date provided
+     * to keystore to check against is reached.
+     */
+    int expiring;
+    /**
+     * The number of signed attestation certificate chains which have not yet been assigned to an
+     * app. This should be less than or equal to signed keys. The remainder of `signed` -
+     * `unassigned` gives the number of signed keys that have been assigned to an app.
+     */
+    int unassigned;
+    /**
+     * The number of signed attestation keys. This should be less than or equal to `total`. The
+     * remainder of `total` - `attested` gives the number of keypairs available to be sent off to
+     * the server for signing.
+     */
+    int attested;
+    /**
+     * The total number of attestation keys.
+     */
+    int total;
+}
diff --git a/keystore2/aidl/android/security/remoteprovisioning/IRemoteProvisioning.aidl b/keystore2/aidl/android/security/remoteprovisioning/IRemoteProvisioning.aidl
new file mode 100644
index 0000000..ecdc790
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/IRemoteProvisioning.aidl
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.security.remoteprovisioning;
+
+import android.hardware.security.keymint.DeviceInfo;
+import android.hardware.security.keymint.ProtectedData;
+import android.hardware.security.keymint.SecurityLevel;
+import android.security.remoteprovisioning.AttestationPoolStatus;
+import android.security.remoteprovisioning.ImplInfo;
+
+/**
+ * `IRemoteProvisioning` is the interface provided to use the remote provisioning functionality
+ * provided through KeyStore. The intent is for a higher level system component to use these
+ * functions in order to drive the process through which the device can receive functioning
+ * attestation certificates.
+ *
+ * ## Error conditions
+ * Error conditions are reported as service specific errors.
+ * Positive codes correspond to `android.security.remoteprovisioning.ResponseCode`
+ * and indicate error conditions diagnosed by the Keystore 2.0 service.
+ * TODO: Remote Provisioning HAL error code info
+ *
+ * `ResponseCode::PERMISSION_DENIED` if the caller does not have the permissions
+ * to use the RemoteProvisioning API. This permission is defined under access_vectors in SEPolicy
+ * in the keystore2 class: remotely_provision
+ *
+ * `ResponseCode::SYSTEM_ERROR` for any unexpected errors like IO or IPC failures.
+ *
+ * @hide
+ */
+interface IRemoteProvisioning {
+
+    /**
+     * Returns the status of the attestation key pool in the database.
+     *
+     * @param expiredBy The date as seconds since epoch by which to judge expiration status of
+     *                        certificates.
+     *
+     * @param secLevel The security level to specify which KM instance to get the pool for.
+     *
+     * @return The `AttestationPoolStatus` parcelable contains fields communicating information
+     *                        relevant to making decisions about when to generate and provision
+     *                        more attestation keys.
+     */
+    AttestationPoolStatus getPoolStatus(in long expiredBy, in SecurityLevel secLevel);
+
+    /**
+     * This is the primary entry point for beginning a remote provisioning flow. The caller
+     * specifies how many CSRs should be generated and provides an X25519 ECDH public key along
+     * with a challenge to encrypt privacy sensitive portions of the returned CBOR blob and
+     * guarantee freshness of the request to the certifying third party.
+     *
+     * ## Error conditions
+     * `ResponseCode::NO_UNSIGNED_KEYS` if there are no unsigned keypairs in the database that can
+     *                         be used for the CSRs.
+     *
+     * A RemoteProvisioning HAL response code may indicate backend errors such as failed EEK
+     *                         verification.
+     *
+     * @param testMode Whether or not the TA implementing the Remote Provisioning HAL should accept
+     *                         any EEK (Endpoint Encryption Key), or only one signed by a chain
+     *                         that verifies back to the Root of Trust baked into the TA. True
+     *                         means that any key is accepted.
+     *
+     * @param numCsr How many certificate signing requests should be generated.
+     *
+     * @param eek A chain of certificates terminating in an X25519 public key, the Endpoint
+     *                         Encryption Key.
+     *
+     * @param challenge A challenge to be included and MACed in the returned CBOR blob.
+     *
+     * @param secLevel The security level to specify which KM instance from which to generate a
+     *                         CSR.
+     *
+     * @param protectedData The encrypted CBOR blob generated by the remote provisioner
+     *
+     * @return A CBOR blob composed of various elements required by the server to verify the
+     *                         request.
+     */
+    byte[] generateCsr(in boolean testMode, in int numCsr, in byte[] eek, in byte[] challenge,
+        in SecurityLevel secLevel, out ProtectedData protectedData, out DeviceInfo deviceInfo);
+
+    /**
+     * This method provides a way for the returned attestation certificate chains to be provisioned
+     * to the attestation key database. When an app requests an attesation key, it will be assigned
+     * one of these certificate chains along with the corresponding private key.
+     *
+     * @param publicKey The raw public key encoded in the leaf certificate.
+     *
+     * @param batchCert The batch certificate corresponding to the attestation key. Separated for
+     *                          the purpose of making Subject lookup for KM attestation easier.
+     *
+     * @param certs An X.509, DER encoded certificate chain for the attestation key.
+     *
+     * @param expirationDate The expiration date on the certificate chain, provided by the caller
+     *                          for convenience.
+     *
+     * @param secLevel The security level representing the KM instance containing the key that this
+     *                          chain corresponds to.
+     */
+    void provisionCertChain(in byte[] publicKey, in byte[] batchCert, in byte[] certs,
+        in long expirationDate, in SecurityLevel secLevel);
+
+    /**
+     * This method allows the caller to instruct KeyStore to generate and store a key pair to be
+     * used for attestation in the `generateCsr` method. The caller should handle spacing out these
+     * requests so as not to jam up the KeyStore work queue.
+     *
+     * @param is_test_mode Instructs the underlying HAL interface to mark the generated key with a
+     *                        tag to indicate that it's for testing.
+     *
+     * @param secLevel The security level to specify which KM instance should generate a key pair.
+     */
+    void generateKeyPair(in boolean is_test_mode, in SecurityLevel secLevel);
+
+    /**
+     * This method returns implementation information for whichever instances of
+     * IRemotelyProvisionedComponent are running on the device. The RemoteProvisioner app needs to
+     * know which KM instances it should be generating and managing attestation keys for, and which
+     * EC curves are supported in those instances.
+     *
+     * @return The array of ImplInfo parcelables.
+     */
+     ImplInfo[] getImplementationInfo();
+
+    /**
+     * This method deletes all remotely provisioned attestation keys in the database, regardless
+     * of what state in their life cycle they are in. This is primarily useful to facilitate
+     * testing.
+     *
+     * @return Number of keys deleted
+     */
+    long deleteAllKeys();
+}
diff --git a/keystore2/aidl/android/security/remoteprovisioning/IRemotelyProvisionedKeyPool.aidl b/keystore2/aidl/android/security/remoteprovisioning/IRemotelyProvisionedKeyPool.aidl
new file mode 100644
index 0000000..7d45e52
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/IRemotelyProvisionedKeyPool.aidl
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 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.
+ */
+
+package android.security.remoteprovisioning;
+
+import android.security.remoteprovisioning.RemotelyProvisionedKey;
+
+/**
+ * This is the interface providing access to remotely-provisioned attestation keys
+ * for an `IRemotelyProvisionedComponent`.
+ *
+ * @hide
+ */
+interface IRemotelyProvisionedKeyPool {
+
+    /**
+     * Fetches an attestation key for the given uid and `IRemotelyProvisionedComponent`, as
+     * identified by the given id.
+
+     * Callers require the keystore2::get_attestation_key permission.
+     *
+     * ## Error conditions
+     * `android.system.keystore2.ResponseCode::PERMISSION_DENIED` if the caller does not have the
+     *      `keystore2::get_attestation_key` permission
+     *
+     * @param clientUid The client application for which an attestation key is needed.
+     *
+     * @param irpcId The unique identifier for the `IRemotelyProvisionedComponent` for which a key
+     *      is requested. This id may be retrieved from a given component via the
+     *      `IRemotelyProvisionedComponent::getHardwareInfo` function.
+     *
+     * @return A `RemotelyProvisionedKey` parcelable containing a key and certification chain for
+     *      the given `IRemotelyProvisionedComponent`.
+     */
+    RemotelyProvisionedKey getAttestationKey(in int clientUid, in @utf8InCpp String irpcId);
+}
diff --git a/keystore2/aidl/android/security/remoteprovisioning/ImplInfo.aidl b/keystore2/aidl/android/security/remoteprovisioning/ImplInfo.aidl
new file mode 100644
index 0000000..9baeb24
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/ImplInfo.aidl
@@ -0,0 +1,37 @@
+/*
+ * 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.
+ */
+
+package android.security.remoteprovisioning;
+
+import android.hardware.security.keymint.SecurityLevel;
+
+/**
+ * This parcelable provides information about the underlying IRemotelyProvisionedComponent
+ * implementation.
+ * @hide
+ */
+parcelable ImplInfo {
+    /**
+     * The security level of the underlying implementation: TEE or StrongBox.
+     */
+    SecurityLevel secLevel;
+    /**
+     * An integer denoting which EC curve is supported in the underlying implementation. The current
+     * options are either P256 or 25519, with values defined in
+     * hardware/interfaces/security/keymint/aidl/.../RpcHardwareInfo.aidl
+     */
+    int supportedCurve;
+}
diff --git a/keystore2/aidl/android/security/remoteprovisioning/RemotelyProvisionedKey.aidl b/keystore2/aidl/android/security/remoteprovisioning/RemotelyProvisionedKey.aidl
new file mode 100644
index 0000000..ae21855
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/RemotelyProvisionedKey.aidl
@@ -0,0 +1,42 @@
+/*
+ * 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.
+ */
+
+package android.security.remoteprovisioning;
+
+/**
+ * A `RemotelyProvisionedKey` holds an attestation key and the corresponding remotely provisioned
+ * certificate chain.
+ *
+ * @hide
+ */
+@RustDerive(Eq=true, PartialEq=true)
+parcelable RemotelyProvisionedKey {
+    /**
+     * The remotely-provisioned key that may be used to sign attestations. The format of this key
+     * is opaque, and need only be understood by the IRemotelyProvisionedComponent that generated
+     * it.
+     *
+     * Any private key material contained within this blob must be encrypted.
+     */
+    byte[] keyBlob;
+
+    /**
+     * Sequence of DER-encoded X.509 certificates that make up the attestation key's certificate
+     * chain. This is the binary encoding for a chain that is supported by Java's
+     * CertificateFactory.generateCertificates API.
+     */
+    byte[] encodedCertChain;
+}
diff --git a/keystore2/aidl/android/security/remoteprovisioning/ResponseCode.aidl b/keystore2/aidl/android/security/remoteprovisioning/ResponseCode.aidl
new file mode 100644
index 0000000..c9877db
--- /dev/null
+++ b/keystore2/aidl/android/security/remoteprovisioning/ResponseCode.aidl
@@ -0,0 +1,34 @@
+/*
+ * 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.
+ */
+
+package android.security.remoteprovisioning;
+
+@Backing(type="int")
+/** @hide */
+enum ResponseCode {
+    /**
+     * Returned if there are no keys available in the database to be used in a CSR
+     */
+    NO_UNSIGNED_KEYS = 1,
+    /**
+     * The caller has imrproper SELinux permissions to access the Remote Provisioning API.
+     */
+    PERMISSION_DENIED = 2,
+    /**
+     * An unexpected error occurred, likely with IO or IPC.
+     */
+    SYSTEM_ERROR = 3,
+}