Adding tests to validate deleteKey APIs.

- Generate a key and delete it using keystore2 service `deleteKey` API.
  Test should delete the key successfully.

- Try to delete a non-existing key with keystore2 service `deleteKey`
  API. Test should fail to delete a key with an error response code
  `KEY_NOT_FOUND`.

- Try to delete a key with domain `BLOB` using keystore2 service
  `deleteKey` API. Test should fail to delete a key with an error code
  `INVALID_ARGUMENT`.

- Generate a key with domain `BLOB`. Delete the generated key using
  underlying security level `deleteKey` API. Test should successfully
  delete key blob.

- Try to delete a key with domain `BLOB` without providing key-blob.
  Test should fail to delete a key with an error code
  `INVALID_ARGUMENT`.

- Try to delete a key with domain `APP` using underlying security level
  `deleteKey` API. Test should fail to delete with an error code
  `INVALID_ARGUMENT`.

Bug: 194359114
Test: atest keystore2_client_test
Change-Id: I8233ef79b33daff868ad9767903169dc21f4906e
diff --git a/keystore2/tests/keystore2_client_delete_key_tests.rs b/keystore2/tests/keystore2_client_delete_key_tests.rs
new file mode 100644
index 0000000..2a06edb
--- /dev/null
+++ b/keystore2/tests/keystore2_client_delete_key_tests.rs
@@ -0,0 +1,150 @@
+// 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.
+
+use nix::unistd::getuid;
+
+use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
+    ErrorCode::ErrorCode, SecurityLevel::SecurityLevel,
+};
+use android_system_keystore2::aidl::android::system::keystore2::{
+    Domain::Domain, KeyDescriptor::KeyDescriptor, ResponseCode::ResponseCode,
+};
+
+use keystore2_test_utils::{get_keystore_service, key_generations, key_generations::Error};
+
+/// Generate a key and delete it using keystore2 service `deleteKey` API. Test should successfully
+/// delete the generated key.
+#[test]
+fn keystore2_delete_key_success() {
+    let keystore2 = get_keystore_service();
+    let sec_level = keystore2.getSecurityLevel(SecurityLevel::TRUSTED_ENVIRONMENT).unwrap();
+    let alias = "delete_key_success_key";
+
+    let key_metadata = key_generations::generate_ec_p256_signing_key(
+        &sec_level,
+        Domain::APP,
+        -1,
+        Some(alias.to_string()),
+        None,
+    )
+    .unwrap();
+
+    keystore2.deleteKey(&key_metadata.key).expect("Failed to delete a key.");
+
+    // Check wehther deleted key is removed from keystore.
+    let result = key_generations::map_ks_error(keystore2.getKeyEntry(&key_metadata.key));
+    assert!(result.is_err());
+    assert_eq!(Error::Rc(ResponseCode::KEY_NOT_FOUND), result.unwrap_err());
+}
+
+/// Try to delete non-existing key with domain other than BLOB using keystore2 service `deleteKey`
+/// API. Test should fail with an error code `KEY_NOT_FOUND`.
+#[test]
+fn keystore2_delete_key_fail() {
+    let test_alias = "delete_key_failure_key";
+    let keystore2 = get_keystore_service();
+
+    let result = key_generations::map_ks_error(keystore2.deleteKey(&KeyDescriptor {
+        domain: Domain::SELINUX,
+        nspace: key_generations::SELINUX_SHELL_NAMESPACE,
+        alias: Some(test_alias.to_string()),
+        blob: None,
+    }));
+    assert!(result.is_err());
+    assert_eq!(Error::Rc(ResponseCode::KEY_NOT_FOUND), result.unwrap_err());
+}
+
+/// Generate a key with `Domain::BLOB`. Try to delete a key with `Domain::BLOB` using keystore2
+/// service `deleteKey` API. Test should fail to delete a key with domain BLOB with an error code
+/// `INVALID_ARGUMENT`.
+#[test]
+fn keystore2_delete_key_with_blob_domain_fail() {
+    let keystore2 = get_keystore_service();
+    let sec_level = keystore2.getSecurityLevel(SecurityLevel::TRUSTED_ENVIRONMENT).unwrap();
+    let alias = "delete_key_blob_fail_key";
+
+    let key_metadata = key_generations::generate_ec_p256_signing_key(
+        &sec_level,
+        Domain::BLOB,
+        key_generations::SELINUX_SHELL_NAMESPACE,
+        Some(alias.to_string()),
+        None,
+    )
+    .unwrap();
+
+    let result = key_generations::map_ks_error(keystore2.deleteKey(&key_metadata.key));
+    assert!(result.is_err());
+    assert_eq!(Error::Rc(ResponseCode::INVALID_ARGUMENT), result.unwrap_err());
+}
+
+/// Generate a key with `Domain::BLOB`. Delete generated key with `Domain::BLOB` using underlying
+/// security level `deleteKey` API. Test should delete the key successfully.
+#[test]
+fn keystore2_delete_key_blob_success() {
+    let keystore2 = get_keystore_service();
+    let sec_level = keystore2.getSecurityLevel(SecurityLevel::TRUSTED_ENVIRONMENT).unwrap();
+    let alias = "delete_key_blob_success_key";
+
+    let key_metadata = key_generations::generate_ec_p256_signing_key(
+        &sec_level,
+        Domain::BLOB,
+        key_generations::SELINUX_SHELL_NAMESPACE,
+        Some(alias.to_string()),
+        None,
+    )
+    .unwrap();
+
+    let result = sec_level.deleteKey(&key_metadata.key);
+    assert!(result.is_ok());
+}
+
+/// Try to delete a key with `Domain::BLOB` without providing key-blob. Test should fail to delete a
+/// key with error code `INVALID_ARGUMENT`.
+#[test]
+fn keystore2_delete_key_fails_with_missing_key_blob() {
+    let keystore2 = get_keystore_service();
+    let sec_level = keystore2.getSecurityLevel(SecurityLevel::TRUSTED_ENVIRONMENT).unwrap();
+
+    let result = key_generations::map_ks_error(sec_level.deleteKey(&KeyDescriptor {
+        domain: Domain::BLOB,
+        nspace: key_generations::SELINUX_SHELL_NAMESPACE,
+        alias: None,
+        blob: None,
+    }));
+    assert!(result.is_err());
+    assert_eq!(Error::Km(ErrorCode::INVALID_ARGUMENT), result.unwrap_err());
+}
+
+/// Try to delete a key with domain other than `Domain::BLOB` using underlying security-level
+/// `deleteKey` API. Test should fail to delete a key-blob from underlying security-level backend
+/// with error code `INVALID_ARGUMENT`.
+#[test]
+fn keystore2_delete_key_blob_fail() {
+    let keystore2 = get_keystore_service();
+    let sec_level = keystore2.getSecurityLevel(SecurityLevel::TRUSTED_ENVIRONMENT).unwrap();
+    let alias = format!("ks_delete_keyblob_test_key_{}", getuid());
+
+    let key_metadata = key_generations::generate_ec_p256_signing_key(
+        &sec_level,
+        Domain::APP,
+        -1,
+        Some(alias),
+        None,
+    )
+    .unwrap();
+
+    let result = key_generations::map_ks_error(sec_level.deleteKey(&key_metadata.key));
+    assert!(result.is_err());
+    assert_eq!(Error::Km(ErrorCode::INVALID_ARGUMENT), result.unwrap_err());
+}
diff --git a/keystore2/tests/keystore2_client_tests.rs b/keystore2/tests/keystore2_client_tests.rs
index d705aa4..e65fedb 100644
--- a/keystore2/tests/keystore2_client_tests.rs
+++ b/keystore2/tests/keystore2_client_tests.rs
@@ -16,6 +16,7 @@
 pub mod keystore2_client_3des_key_tests;
 pub mod keystore2_client_aes_key_tests;
 pub mod keystore2_client_attest_key_tests;
+pub mod keystore2_client_delete_key_tests;
 pub mod keystore2_client_ec_key_tests;
 pub mod keystore2_client_grant_key_tests;
 pub mod keystore2_client_hmac_key_tests;