AuthGraph: add per-role VTS tests
Add VTS tests that just exercise a single role, sink or source.
Use the AuthGraph core library to provide the implementation of the
other role. This means that the tests are best written in Rust.
Put the test code into a library, so that other HALs which include
AuthGraph as a component can exercise the AuthGraph parts in their own
VTS tests.
Test: VtsAidlAuthGraphRoleTest
Bug: 284470121
Change-Id: I73f6aa277b41cc728587d707d7a6f82f0d18e08f
diff --git a/security/authgraph/aidl/vts/functional/sink.rs b/security/authgraph/aidl/vts/functional/sink.rs
new file mode 100644
index 0000000..5c81593
--- /dev/null
+++ b/security/authgraph/aidl/vts/functional/sink.rs
@@ -0,0 +1,214 @@
+/*
+ * 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.
+ */
+
+//! VTS tests for sinks
+use super::*;
+use authgraph_core::traits;
+
+/// Run AuthGraph tests against the provided sink, using a local test source implementation.
+pub fn test(impls: &mut traits::TraitImpl, sink: binder::Strong<dyn IAuthGraphKeyExchange>) {
+ test_mainline(impls, sink.clone());
+ test_corrupt_sig(impls, sink.clone());
+ test_corrupt_keys(impls, sink);
+}
+
+/// Perform mainline AuthGraph key exchange with the provided sink and local implementation.
+/// Return the agreed AES keys in plaintext.
+pub fn test_mainline(
+ impls: &mut traits::TraitImpl,
+ sink: binder::Strong<dyn IAuthGraphKeyExchange>,
+) -> [key::AesKey; 2] {
+ // Step 1: create an ephemeral ECDH key at the (local) source.
+ let source_init_info = ke::create(impls).expect("failed to create() with local impl");
+
+ // Step 2: pass the source's ECDH public key and other session info to the (remote) sink.
+ let init_result = sink
+ .init(
+ &build_plain_pub_key(&source_init_info.ke_key.pub_key),
+ &vec_to_identity(&source_init_info.identity),
+ &source_init_info.nonce,
+ source_init_info.version,
+ )
+ .expect("failed to init() with remote impl");
+ let sink_init_info = init_result.sessionInitiationInfo;
+ let sink_pub_key = extract_plain_pub_key(&sink_init_info.key.pubKey);
+
+ let sink_info = init_result.sessionInfo;
+ assert!(!sink_info.sessionId.is_empty());
+
+ // The AuthGraph core library will verify the session ID signature, but do it here too.
+ let sink_verification_key =
+ verification_key_from_identity(&impls, &sink_init_info.identity.identity);
+ ke::verify_signature_on_session_id(
+ &sink_verification_key,
+ &sink_info.sessionId,
+ &sink_info.signature.signature,
+ &*impls.ecdsa,
+ )
+ .expect("failed verification of signed session ID");
+
+ // Step 3: pass the sink's ECDH public key and other session info to the (local) source, so it
+ // can calculate the same pair of symmetric keys.
+ let source_info = ke::finish(
+ impls,
+ &sink_pub_key.plainPubKey,
+ &sink_init_info.identity.identity,
+ &sink_info.signature.signature,
+ &sink_init_info.nonce,
+ sink_init_info.version,
+ source_init_info.ke_key,
+ )
+ .expect("failed to finish() with local impl");
+ assert!(!source_info.session_id.is_empty());
+
+ // The AuthGraph core library will verify the session ID signature, but do it here too.
+ let source_verification_key =
+ verification_key_from_identity(&impls, &source_init_info.identity);
+ ke::verify_signature_on_session_id(
+ &source_verification_key,
+ &source_info.session_id,
+ &source_info.session_id_signature,
+ &*impls.ecdsa,
+ )
+ .expect("failed verification of signed session ID");
+
+ // Both ends should agree on the session ID.
+ assert_eq!(source_info.session_id, sink_info.sessionId);
+
+ // Step 4: pass the (local) source's session ID signature back to the sink, so it can check it
+ // and update the symmetric keys so they're marked as authentication complete.
+ let _sink_arcs = sink
+ .authenticationComplete(
+ &vec_to_signature(&source_info.session_id_signature),
+ &sink_info.sharedKeys,
+ )
+ .expect("failed to authenticationComplete() with remote sink");
+
+ // Decrypt and return the session keys.
+ decipher_aes_keys(&impls, &source_info.shared_keys)
+}
+
+/// Perform mainline AuthGraph key exchange with the provided sink, but provide an invalid
+/// session ID signature.
+pub fn test_corrupt_sig(
+ impls: &mut traits::TraitImpl,
+ sink: binder::Strong<dyn IAuthGraphKeyExchange>,
+) {
+ // Step 1: create an ephemeral ECDH key at the (local) source.
+ let source_init_info = ke::create(impls).expect("failed to create() with local impl");
+
+ // Step 2: pass the source's ECDH public key and other session info to the (remote) sink.
+ let init_result = sink
+ .init(
+ &build_plain_pub_key(&source_init_info.ke_key.pub_key),
+ &vec_to_identity(&source_init_info.identity),
+ &source_init_info.nonce,
+ source_init_info.version,
+ )
+ .expect("failed to init() with remote impl");
+ let sink_init_info = init_result.sessionInitiationInfo;
+ let sink_pub_key = extract_plain_pub_key(&sink_init_info.key.pubKey);
+
+ let sink_info = init_result.sessionInfo;
+ assert!(!sink_info.sessionId.is_empty());
+
+ // Step 3: pass the sink's ECDH public key and other session info to the (local) source, so it
+ // can calculate the same pair of symmetric keys.
+ let source_info = ke::finish(
+ impls,
+ &sink_pub_key.plainPubKey,
+ &sink_init_info.identity.identity,
+ &sink_info.signature.signature,
+ &sink_init_info.nonce,
+ sink_init_info.version,
+ source_init_info.ke_key,
+ )
+ .expect("failed to finish() with local impl");
+ assert!(!source_info.session_id.is_empty());
+
+ // Build a corrupted version of the (local) source's session ID signature.
+ let mut corrupt_signature = source_info.session_id_signature.clone();
+ let sig_len = corrupt_signature.len();
+ corrupt_signature[sig_len - 1] ^= 0x01;
+
+ // Step 4: pass the (local) source's **invalid** session ID signature back to the sink,
+ // which should reject it.
+ let result =
+ sink.authenticationComplete(&vec_to_signature(&corrupt_signature), &sink_info.sharedKeys);
+ let err = result.expect_err("expect failure with corrupt signature");
+ assert_eq!(
+ err,
+ binder::Status::new_service_specific_error(Error::INVALID_SIGNATURE.0, None)
+ );
+}
+
+/// Perform mainline AuthGraph key exchange with the provided sink, but provide an invalid
+/// Arc for the sink's key.
+pub fn test_corrupt_keys(
+ impls: &mut traits::TraitImpl,
+ sink: binder::Strong<dyn IAuthGraphKeyExchange>,
+) {
+ // Step 1: create an ephemeral ECDH key at the (local) source.
+ let source_init_info = ke::create(impls).expect("failed to create() with local impl");
+
+ // Step 2: pass the source's ECDH public key and other session info to the (remote) sink.
+ let init_result = sink
+ .init(
+ &build_plain_pub_key(&source_init_info.ke_key.pub_key),
+ &vec_to_identity(&source_init_info.identity),
+ &source_init_info.nonce,
+ source_init_info.version,
+ )
+ .expect("failed to init() with remote impl");
+ let sink_init_info = init_result.sessionInitiationInfo;
+ let sink_pub_key = extract_plain_pub_key(&sink_init_info.key.pubKey);
+
+ let sink_info = init_result.sessionInfo;
+ assert!(!sink_info.sessionId.is_empty());
+
+ // Step 3: pass the sink's ECDH public key and other session info to the (local) source, so it
+ // can calculate the same pair of symmetric keys.
+ let source_info = ke::finish(
+ impls,
+ &sink_pub_key.plainPubKey,
+ &sink_init_info.identity.identity,
+ &sink_info.signature.signature,
+ &sink_init_info.nonce,
+ sink_init_info.version,
+ source_init_info.ke_key,
+ )
+ .expect("failed to finish() with local impl");
+ assert!(!source_info.session_id.is_empty());
+
+ // Deliberately corrupt the sink's shared key Arcs before returning them
+ let mut corrupt_keys = sink_info.sharedKeys.clone();
+ let len0 = corrupt_keys[0].arc.len();
+ let len1 = corrupt_keys[1].arc.len();
+ corrupt_keys[0].arc[len0 - 1] ^= 0x01;
+ corrupt_keys[1].arc[len1 - 1] ^= 0x01;
+
+ // Step 4: pass the (local) source's session ID signature back to the sink, but with corrupted
+ // keys, which should be rejected.
+ let result = sink.authenticationComplete(
+ &vec_to_signature(&source_info.session_id_signature),
+ &corrupt_keys,
+ );
+ let err = result.expect_err("expect failure with corrupt keys");
+ assert_eq!(
+ err,
+ binder::Status::new_service_specific_error(Error::INVALID_SHARED_KEY_ARCS.0, None)
+ );
+}