Test Suite: Circuit Relay V2 — Signed Peer Record (SPR) Integration

[seetadev]

Purpose

This test suite ensures that:

1. HOP and STOP message flows correctly include, parse, and verify the senderRecord (Signed Peer Record).
2. The implementation correctly compares the actual sender’s PeerId with the PeerId in the envelope.
3. The new logic paths added to relay/circuit_v2/protocol.py are covered by tests (as noted in Pacrob’s review).

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Test Categories

1. HOP Message with Valid SPR

Goal: Verify that a HOP message containing a valid senderRecord is:

• Parsed correctly.
• Authenticated against the sender’s PeerId.
• Propagated correctly to the next peer.

Test Steps:

1. Create mock peers: src_peer, relay_peer, dst_peer.

2. Generate a valid SignedPeerRecord for src_peer.

3. Send a simulated HOP message from src_peer → relay_peer, including the senderRecord.

4. Ensure:

   • The relay’s handler parses the senderRecord field (HasField("senderRecord") == True).
   • The PeerId extracted from the record matches src_peer.get_id().
   • The connection is allowed to proceed.

Assertions:

• stop_msg.senderRecord.peer_id == src_peer.id
• relay.accepted_hop == True

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2. HOP Message with Invalid SPR

Goal: Verify rejection when the senderRecord is tampered or invalid.

Test Steps:

1. Same setup as above, but modify the signature or peer id in the SPR.

2. Send HOP message with corrupted senderRecord.

3. Verify that:

   • Relay rejects the HOP.
   • Appropriate error (e.g. InvalidPeerRecord or VerificationFailed) is raised or logged.

Assertions:

• relay.accepted_hop == False
• relay.error_log contains “peer record verification failed”

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3. STOP Message Parsing and Validation

Goal: Cover the untested code path Pacrob pointed out:

stop_msg = StopMessage()
stop_msg.ParseFromString(msg_bytes)

if stop_msg.HasField("senderRecord"):

Test Steps:

1. Send a simulated STOP message containing a valid senderRecord.

2. Ensure:

   • stop_msg.HasField("senderRecord") evaluates to True.
   • The handler validates and compares the sender’s ID with the one in the envelope.
   • The relay correctly finalizes the STOP sequence if validation succeeds.

Assertions:

• stop_msg.senderRecord.peer_id == expected_peer_id
• stop_handler.was_called == True

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4. Missing SPR Field

Goal: Test fallback behavior when no senderRecord field exists.

Test Steps:

1. Send a STOP or HOP message without a senderRecord.

2. Verify that:

   • The handler continues gracefully (doesn’t crash or throw unexpected exceptions).
   • The relay may default to unauthenticated mode if allowed.

Assertions:

• stop_msg.HasField("senderRecord") == False
• relay.logged_warning == "Missing senderRecord"

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5. get_remote_peer_id Validation

Goal: Validate logic around:

src_peer_id = cast(INetStreamWithExtras, src_stream).get_remote_peer_id()

and

dst_peer_id = cast(INetStreamWithExtras, stream).get_remote_peer_id()

Test Steps:

1. Mock an INetStreamWithExtras instance to simulate both source and destination peers.

2. Ensure that:

   • get_remote_peer_id() returns consistent and correct PeerIds.
   • If undefined or mismatched, the handler raises or logs an error.

3. Add assertions that the retrieved PeerIds are compared properly to envelope IDs.

Assertions:

• src_peer_id == stop_msg.senderRecord.peer_id
• If mismatch: relay.error_log contains “peer id mismatch in envelope”

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6. End-to-End Relay Flow with Verified SPRs

Goal: Full integration test for a complete HOP–STOP exchange through relay.

Test Steps:

1. Initialize src_peer, relay_peer, and dst_peer using mock host/network.

2. src_peer sends a HOP request with a valid SPR.

3. relay_peer processes and forwards the connection setup.

4. dst_peer responds with a STOP message containing its SPR.

5. Verify:

   • Each peer validates the incoming SPR.
   • Connection is established only if both validations pass.

Assertions:

• relay.connection_established == True
• Both peers’ peerstore entries updated with each other’s verified records.

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7. Edge Case — Expired or Replay SPR

Goal: Test temporal validity or replay attack resistance if timestamp or sequence number is present in SPR.

Test Steps:

1. Create a Signed Peer Record with an old timestamp.
2. Send it via HOP/STOP.
3. Verify that handler rejects it due to being expired.

Assertions:

• relay.reject_reason == "stale peer record"

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Mocks / Helpers Needed

• MockStream subclass implementing INetStreamWithExtras.get_remote_peer_id().
• FakePeerstore to simulate peer records and lookups.
• generate_signed_peer_record(peer_id, private_key) utility for test data.
• FakeRelayHost that logs calls like accepted_hop, error_log, and connection_established.

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Coverage Goals

• Ensure tests hit every new code branch involving:

  • stop_msg.HasField("senderRecord")
  • get_remote_peer_id() calls
  • SPR verification and comparison

• Aim for >90% coverage for the updated relay/circuit_v2/protocol.py file.