test: 15 cross-project integration tests — WZP ↔ featherChat verified

Identity (6 tests):
- Same seed → same Ed25519/X25519 keys, same fingerprint, same display
- Random seed, raw HKDF output verified

BIP39 Mnemonic (3 tests):
- Roundtrip both directions, identical strings

CallSignal Interop (4 tests):
- Offer/Answer/Hangup roundtrip through FC bincode serialization
- Signal type mapping verified

Auth Contract (2 tests):
- Request/response shapes match between WZP and FC

Uses warzone-protocol v0.0.21 as real dependency.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/wzp-crypto/Cargo.toml

@@ -18,4 +18,15 @@ tracing = { workspace = true }
 bip39 = "2"
 hex = "0.4"
 
+# featherChat identity — the source of truth for Seed, IdentityKeyPair, Fingerprint
+warzone-protocol = { path = "../../deps/featherchat/warzone/crates/warzone-protocol" }
+
 [dev-dependencies]
+ed25519-dalek = { workspace = true }
+warzone-protocol = { path = "../../deps/featherchat/warzone/crates/warzone-protocol" }
+wzp-proto = { workspace = true }
+wzp-client = { path = "../wzp-client" }
+wzp-relay = { path = "../wzp-relay" }
+serde_json = "1"
+serde = { workspace = true }
+bincode = "1"

crates/wzp-crypto/tests/featherchat_compat.rs

@@ -0,0 +1,313 @@
+//! Cross-project compatibility tests between WZP and featherChat.
+//!
+//! Verifies:
+//! 1. Identity: same seed → same keys → same fingerprints (WZP-FC-8)
+//! 2. CallSignal: WZP SignalMessage serializes into FC CallSignal.payload correctly
+//! 3. Auth: WZP auth module request/response matches FC's /v1/auth/validate contract
+//! 4. Mnemonic: BIP39 interop between both implementations
+
+use wzp_proto::KeyExchange;
+
+// ─── Identity Compatibility (WZP-FC-8) ──────────────────────────────────────
+
+#[test]
+fn same_seed_same_ed25519_key() {
+    let seed = [42u8; 32];
+
+    let wzp_kx = wzp_crypto::WarzoneKeyExchange::from_identity_seed(&seed);
+    let wzp_pub = wzp_kx.identity_public_key();
+
+    let fc_seed = warzone_protocol::identity::Seed::from_bytes(seed);
+    let fc_id = fc_seed.derive_identity();
+    let fc_pub = fc_id.signing.verifying_key();
+
+    assert_eq!(&wzp_pub, fc_pub.as_bytes(), "Ed25519 keys must match");
+}
+
+#[test]
+fn same_seed_same_fingerprint() {
+    let seed = [99u8; 32];
+
+    let wzp_kx = wzp_crypto::WarzoneKeyExchange::from_identity_seed(&seed);
+    let wzp_fp = wzp_kx.fingerprint();
+
+    let fc_seed = warzone_protocol::identity::Seed::from_bytes(seed);
+    let fc_fp = fc_seed.derive_identity().public_identity().fingerprint.0;
+
+    assert_eq!(wzp_fp, fc_fp, "Fingerprints must match");
+}
+
+#[test]
+fn wzp_identity_module_matches_featherchat() {
+    let seed = [0xAB; 32];
+
+    let wzp_pub = wzp_crypto::Seed::from_bytes(seed)
+        .derive_identity()
+        .public_identity();
+
+    let fc_pub = warzone_protocol::identity::Seed::from_bytes(seed)
+        .derive_identity()
+        .public_identity();
+
+    assert_eq!(wzp_pub.signing.as_bytes(), fc_pub.signing.as_bytes());
+    assert_eq!(wzp_pub.encryption.as_bytes(), fc_pub.encryption.as_bytes());
+    assert_eq!(wzp_pub.fingerprint.0, fc_pub.fingerprint.0);
+    assert_eq!(wzp_pub.fingerprint.to_string(), fc_pub.fingerprint.to_string());
+}
+
+#[test]
+fn random_seed_identity_match() {
+    let fc_seed = warzone_protocol::identity::Seed::generate();
+    let raw = fc_seed.0;
+
+    let fc_fp = fc_seed.derive_identity().public_identity().fingerprint.0;
+    let wzp_fp = wzp_crypto::WarzoneKeyExchange::from_identity_seed(&raw).fingerprint();
+
+    assert_eq!(wzp_fp, fc_fp);
+}
+
+#[test]
+fn hkdf_derive_matches() {
+    let seed = [0x55; 32];
+
+    let fc_ed = warzone_protocol::crypto::hkdf_derive(&seed, b"", b"warzone-ed25519", 32);
+    let fc_signing = ed25519_dalek::SigningKey::from_bytes(&fc_ed.try_into().unwrap());
+    let fc_pub = fc_signing.verifying_key();
+
+    let wzp_pub = wzp_crypto::WarzoneKeyExchange::from_identity_seed(&seed).identity_public_key();
+
+    assert_eq!(&wzp_pub, fc_pub.as_bytes());
+}
+
+// ─── BIP39 Mnemonic Interop ─────────────────────────────────────────────────
+
+#[test]
+fn mnemonic_roundtrip_fc_to_wzp() {
+    let seed = [0x77; 32];
+    let fc_mnemonic = warzone_protocol::identity::Seed::from_bytes(seed).to_mnemonic();
+    let wzp_recovered = wzp_crypto::Seed::from_mnemonic(&fc_mnemonic).unwrap();
+    assert_eq!(wzp_recovered.0, seed);
+}
+
+#[test]
+fn mnemonic_roundtrip_wzp_to_fc() {
+    let seed = [0x33; 32];
+    let wzp_mnemonic = wzp_crypto::Seed::from_bytes(seed).to_mnemonic();
+    let fc_recovered = warzone_protocol::identity::Seed::from_mnemonic(&wzp_mnemonic).unwrap();
+    assert_eq!(fc_recovered.0, seed);
+}
+
+#[test]
+fn mnemonic_strings_identical() {
+    let seed = [0xDE; 32];
+    let fc_words = warzone_protocol::identity::Seed::from_bytes(seed).to_mnemonic();
+    let wzp_words = wzp_crypto::Seed::from_bytes(seed).to_mnemonic();
+    assert_eq!(fc_words, wzp_words);
+}
+
+// ─── CallSignal Payload Interop ─────────────────────────────────────────────
+
+#[test]
+fn wzp_signal_serializes_into_fc_callsignal_payload() {
+    // WZP creates a CallOffer SignalMessage
+    let offer = wzp_proto::SignalMessage::CallOffer {
+        identity_pub: [1u8; 32],
+        ephemeral_pub: [2u8; 32],
+        signature: vec![3u8; 64],
+        supported_profiles: vec![wzp_proto::QualityProfile::GOOD],
+    };
+
+    // Encode as featherChat CallSignal payload
+    let payload = wzp_client::featherchat::encode_call_payload(
+        &offer,
+        Some("relay.example.com:4433"),
+        Some("myroom"),
+    );
+
+    // Verify it's valid JSON
+    let parsed: serde_json::Value = serde_json::from_str(&payload).unwrap();
+    assert!(parsed.get("signal").is_some());
+    assert_eq!(parsed["relay_addr"], "relay.example.com:4433");
+    assert_eq!(parsed["room"], "myroom");
+
+    // featherChat would put this in WireMessage::CallSignal { payload, ... }
+    // Verify the FC side can create a CallSignal with this payload
+    let fc_msg = warzone_protocol::message::WireMessage::CallSignal {
+        id: "call-123".to_string(),
+        sender_fingerprint: "abcd1234".to_string(),
+        signal_type: warzone_protocol::message::CallSignalType::Offer,
+        payload: payload.clone(),
+        target: "peer-fingerprint".to_string(),
+    };
+
+    // Verify it serializes with bincode (FC's wire format)
+    let encoded = bincode::serialize(&fc_msg).unwrap();
+    assert!(!encoded.is_empty());
+
+    // And deserializes back
+    let decoded: warzone_protocol::message::WireMessage = bincode::deserialize(&encoded).unwrap();
+    if let warzone_protocol::message::WireMessage::CallSignal {
+        id, payload: p, signal_type, ..
+    } = decoded
+    {
+        assert_eq!(id, "call-123");
+        assert!(matches!(signal_type, warzone_protocol::message::CallSignalType::Offer));
+
+        // Decode the WZP payload back
+        let wzp_payload = wzp_client::featherchat::decode_call_payload(&p).unwrap();
+        assert_eq!(wzp_payload.relay_addr.unwrap(), "relay.example.com:4433");
+        assert!(matches!(wzp_payload.signal, wzp_proto::SignalMessage::CallOffer { .. }));
+    } else {
+        panic!("expected CallSignal");
+    }
+}
+
+#[test]
+fn wzp_answer_round_trips_through_fc_callsignal() {
+    let answer = wzp_proto::SignalMessage::CallAnswer {
+        identity_pub: [10u8; 32],
+        ephemeral_pub: [20u8; 32],
+        signature: vec![30u8; 64],
+        chosen_profile: wzp_proto::QualityProfile::DEGRADED,
+    };
+
+    let payload = wzp_client::featherchat::encode_call_payload(&answer, None, None);
+
+    let fc_msg = warzone_protocol::message::WireMessage::CallSignal {
+        id: "call-456".to_string(),
+        sender_fingerprint: "efgh5678".to_string(),
+        signal_type: warzone_protocol::message::CallSignalType::Answer,
+        payload,
+        target: "caller-fp".to_string(),
+    };
+
+    let bytes = bincode::serialize(&fc_msg).unwrap();
+    let decoded: warzone_protocol::message::WireMessage = bincode::deserialize(&bytes).unwrap();
+
+    if let warzone_protocol::message::WireMessage::CallSignal { payload, .. } = decoded {
+        let wzp = wzp_client::featherchat::decode_call_payload(&payload).unwrap();
+        if let wzp_proto::SignalMessage::CallAnswer { chosen_profile, .. } = wzp.signal {
+            assert_eq!(chosen_profile.codec, wzp_proto::CodecId::Opus6k);
+        } else {
+            panic!("expected CallAnswer");
+        }
+    }
+}
+
+#[test]
+fn wzp_hangup_round_trips_through_fc_callsignal() {
+    let hangup = wzp_proto::SignalMessage::Hangup {
+        reason: wzp_proto::HangupReason::Normal,
+    };
+
+    let payload = wzp_client::featherchat::encode_call_payload(&hangup, None, None);
+    let signal_type = wzp_client::featherchat::signal_to_call_type(&hangup);
+    assert!(matches!(signal_type, wzp_client::featherchat::CallSignalType::Hangup));
+
+    let fc_msg = warzone_protocol::message::WireMessage::CallSignal {
+        id: "call-789".to_string(),
+        sender_fingerprint: "xyz".to_string(),
+        signal_type: warzone_protocol::message::CallSignalType::Hangup,
+        payload,
+        target: "peer".to_string(),
+    };
+
+    let bytes = bincode::serialize(&fc_msg).unwrap();
+    let decoded: warzone_protocol::message::WireMessage = bincode::deserialize(&bytes).unwrap();
+
+    if let warzone_protocol::message::WireMessage::CallSignal { payload, .. } = decoded {
+        let wzp = wzp_client::featherchat::decode_call_payload(&payload).unwrap();
+        assert!(matches!(wzp.signal, wzp_proto::SignalMessage::Hangup { .. }));
+    }
+}
+
+// ─── Auth Token Contract ────────────────────────────────────────────────────
+
+#[test]
+fn auth_validate_request_matches_fc_contract() {
+    // WZP sends: { "token": "..." }
+    // FC expects: ValidateRequest { token: String }
+    let wzp_request = serde_json::json!({ "token": "test-token-123" });
+    let json_str = wzp_request.to_string();
+
+    // FC can deserialize this (same shape as their ValidateRequest)
+    #[derive(serde::Deserialize)]
+    struct FcValidateRequest {
+        token: String,
+    }
+    let fc_req: FcValidateRequest = serde_json::from_str(&json_str).unwrap();
+    assert_eq!(fc_req.token, "test-token-123");
+}
+
+#[test]
+fn auth_validate_response_matches_wzp_expectations() {
+    // FC returns: { "valid": true, "fingerprint": "...", "alias": "..." }
+    // WZP expects: wzp_relay::auth::ValidateResponse
+    let fc_response = serde_json::json!({
+        "valid": true,
+        "fingerprint": "a3f8:1b2c:3d4e:5f60:7182:93a4:b5c6:d7e8",
+        "alias": "manwe",
+        "eth_address": null
+    });
+
+    let wzp_resp: wzp_relay::auth::ValidateResponse =
+        serde_json::from_value(fc_response).unwrap();
+    assert!(wzp_resp.valid);
+    assert_eq!(
+        wzp_resp.fingerprint.unwrap(),
+        "a3f8:1b2c:3d4e:5f60:7182:93a4:b5c6:d7e8"
+    );
+    assert_eq!(wzp_resp.alias.unwrap(), "manwe");
+}
+
+#[test]
+fn auth_invalid_response_matches() {
+    let fc_response = serde_json::json!({ "valid": false });
+    let wzp_resp: wzp_relay::auth::ValidateResponse =
+        serde_json::from_value(fc_response).unwrap();
+    assert!(!wzp_resp.valid);
+    assert!(wzp_resp.fingerprint.is_none());
+}
+
+// ─── Signal Type Mapping ────────────────────────────────────────────────────
+
+#[test]
+fn all_signal_types_map_correctly() {
+    use wzp_client::featherchat::{signal_to_call_type, CallSignalType};
+
+    let cases: Vec<(wzp_proto::SignalMessage, &str)> = vec![
+        (
+            wzp_proto::SignalMessage::CallOffer {
+                identity_pub: [0; 32], ephemeral_pub: [0; 32],
+                signature: vec![], supported_profiles: vec![],
+            },
+            "Offer",
+        ),
+        (
+            wzp_proto::SignalMessage::CallAnswer {
+                identity_pub: [0; 32], ephemeral_pub: [0; 32],
+                signature: vec![],
+                chosen_profile: wzp_proto::QualityProfile::GOOD,
+            },
+            "Answer",
+        ),
+        (
+            wzp_proto::SignalMessage::IceCandidate {
+                candidate: "candidate:1".to_string(),
+            },
+            "IceCandidate",
+        ),
+        (
+            wzp_proto::SignalMessage::Hangup {
+                reason: wzp_proto::HangupReason::Normal,
+            },
+            "Hangup",
+        ),
+    ];
+
+    for (signal, expected_name) in cases {
+        let ct = signal_to_call_type(&signal);
+        let name = format!("{ct:?}");
+        assert_eq!(name, expected_name, "signal type mapping for {expected_name}");
+    }
+}