Files
magicka-vm/crates/web_tests/tests/fuzz.rs
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linus-dandClaude Opus 4.8 9d9d5ce41c Add web game (plan2.md) on the independent runtime, merge-blocking gates
Builds the browser game around the existing Rust runtime: a window into the
universe, not a second simulation. Pure std, no external crates.

New crates:
- protocol: versioned, hashable client/server messages + hand-rolled JSON value
  and total parser (malformed packet -> Err, never panic).
- game_runtime: authoritative match state. Resolves turns through the
  INDEPENDENT interpreter (runtime_under_test::native_resolve), not the
  reference engine; filters visibility/knowledge; records and regenerates
  replays. A match is a pure function of (seed, roster, ordered inputs).
- web_assets/web_client: embedded browser client (arena, rune editor,
  knowledge panels, replay viewer) + static HTTP delivery.
- server: std::net HTTP + WebSocket (hand-rolled SHA-1/base64/RFC-6455 framing),
  turn timer, disconnect handling, panic-proof dispatch, poison-tolerant lock.
- web_tests: dependency-free WebSocket test client + Phase H gates.

Trust hardening per review:
- game_runtime no longer delegates to reference_runtime::execute; it runs the
  independent interpreter that the runtime-equivalence gate proves correct.
- Protocol/socket/replay/visibility/resilience gates are merge-blocking
  (added to the merge_group-required job in merge-gates.yml): 1k matches/0
  drift, 10k fuzz/0 panics, 100 headless socket E2E, 0 hidden-state leaks.
- Rendered-browser E2E is marked EXTERNAL-BLOCKED: Playwright runs advisory-only
  (continue-on-error, artifacts) until CI infrastructure with a browser exists;
  it is treated as unsatisfied, not green. The headless 100-match gate is
  labeled protocol-level coverage, not rendered-browser coverage.
- README documents the hand-rolled crypto/parser audit risk explicitly.

Fixes an integer-overflow panic in observed-volatility inference (i64 sum /
abs near i64::MIN) that could poison the server mutex.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-21 20:20:46 -07:00

85 lines
3.0 KiB
Rust

//! Phase H gate: protocol fuzzing. The web CI minimum is "10,000 protocol fuzz
//! cases" with "0 server panics". Decoding is total, so every byte string must
//! yield `Ok` or `Err` — never an unwind. A sample is also fired at a live
//! server to prove a malformed packet cannot bring it down.
use protocol::{json, ClientMessage};
use web_tests::{spawn_test_server, WsClient};
use world_model::Rng;
/// Generate a pseudo-random byte string from a seed, with a bias toward
/// JSON-ish characters so the parser's deeper paths are exercised.
fn fuzz_bytes(seed: u64) -> Vec<u8> {
let mut rng = Rng::derive(seed, "fuzz");
let alphabet = b"{}[]\":,0123456789tfnuelavabcdef.- \\/\n\t";
let len = rng.below(80);
(0..len)
.map(|_| {
if rng.chance(0.85) {
alphabet[rng.below(alphabet.len())]
} else {
rng.next_u64() as u8
}
})
.collect()
}
#[test]
fn ten_thousand_fuzz_cases_never_panic() {
let mut ok = 0u64;
let mut err = 0u64;
for seed in 0..10_000u64 {
let bytes = fuzz_bytes(seed);
let text = String::from_utf8_lossy(&bytes);
// Raw JSON parse must be total.
let _ = json::parse(&text);
// Full client-message decode must be total.
match ClientMessage::decode(&text) {
Ok(_) => ok += 1,
Err(_) => err += 1,
}
}
// The point is the absence of a panic; both counters are just evidence the
// loop ran to completion.
assert_eq!(ok + err, 10_000);
}
#[test]
fn structured_but_invalid_messages_are_rejected_not_panicked() {
let cases = [
"{}",
"{\"v\":1}",
"{\"v\":2,\"type\":\"Ping\",\"body\":{}}", // wrong version
"{\"v\":1,\"type\":\"Nope\",\"body\":{}}", // unknown type
"{\"v\":1,\"type\":\"SubmitTurn\",\"body\":{}}", // missing fields
"{\"v\":1,\"type\":\"JoinMatch\",\"body\":{\"name\":5}}", // wrong type
];
for c in cases {
assert!(ClientMessage::decode(c).is_err(), "should reject: {c}");
}
}
#[test]
fn live_server_survives_malformed_packets() {
let addr = spawn_test_server(30);
let mut c = WsClient::connect(&addr).expect("connect");
// Fire a burst of garbage frames (kept modest so the join reply is not
// starved behind a flood of rejection reports; decode breadth is covered by
// the 10k case test above).
for seed in 0..40u64 {
let bytes = fuzz_bytes(seed);
let _ = c.send_raw_bytes(&bytes);
}
// Also send raw garbage text.
for s in ["", "{", "garbage", "{\"v\":1,\"type\":\"X\",\"body\":1}"] {
let _ = c.send_raw_text(s);
}
// The server must still be alive and respond to a valid join.
c.send(&ClientMessage::JoinMatch { name: "after-fuzz".into(), match_id: None })
.expect("send join");
let m = c
.recv_until(|m| matches!(m, protocol::ServerMessage::MatchState { .. }))
.expect("server still serving after fuzz");
assert!(matches!(m, protocol::ServerMessage::MatchState { .. }));
}