Files
DECNET/tests/canary/test_worker_http.py
anti dd807bc55e feat(canary): worker decodes ?d=/?o=/?s=&i=&n=&d= fingerprint params
The fingerprint payload beacons fingerprint data as base64url JSON in
GET query params: ?o=1 for the bare-open beacon, ?d=<blob> for a
single-shot dump, or ?s/i/n/d=<chunk> for chunked dumps. Until now
those params were buried inside request_path; consumers had to parse
the URL themselves.

Worker now extracts them in _extract_fingerprint and merges into
raw_headers under reserved _fp* keys:

* _fp_open       — bare-open marker
* _fp            — decoded fingerprint dict (single-shot path)
* _fp_sid/idx/total/chunk — chunked metadata + raw base64 (reassembly
  is a downstream concern, not the worker's job)
* _fp_decode_error / _fp_oversize — failure markers for trash dumps

Per-chunk size capped at 8KB so an attacker spamming /c/<known_slug>
can't inflate trigger rows indefinitely. Decode failures degrade
gracefully — the trigger row still records the hit, just with a
_fp_decode_error flag instead of structured fingerprint data.

Tests cover the single-shot decode, bare-open flag, chunked metadata,
malformed input, and oversize drop paths.
2026-04-29 16:25:17 -04:00

229 lines
8.1 KiB
Python

"""HTTP surface coverage for the canary worker.
We exercise the FastAPI app via Starlette's TestClient so the test
doesn't need a real socket. Asserts:
* ``GET /c/{slug}`` for a known slug returns 200 + image/gif, persists
a trigger row, bumps the token's counters, and publishes
``canary.<token_id>.triggered`` on the bus.
* ``GET /c/{slug}`` for an unknown slug returns the same 200 (stealth)
but persists nothing.
* The Server header is rewritten to a generic value (``nginx``).
* Bare root returns 404.
* X-Forwarded-For is honored.
"""
from __future__ import annotations
import asyncio
from typing import AsyncIterator
import pytest
import pytest_asyncio
from fastapi.testclient import TestClient
from decnet.bus import topics
from decnet.bus.fake import FakeBus
from decnet.canary.worker import _build_app
from decnet.web.db.sqlite.repository import SQLiteRepository
import decnet.web.db.models # noqa: F401
@pytest_asyncio.fixture
async def repo(tmp_path) -> AsyncIterator[SQLiteRepository]:
r = SQLiteRepository(str(tmp_path / "w.db"))
await r.initialize()
yield r
@pytest_asyncio.fixture
async def bus() -> AsyncIterator[FakeBus]:
b = FakeBus()
await b.connect()
yield b
await b.close()
@pytest.mark.asyncio
async def test_known_slug_records_trigger_and_publishes(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
await repo.create_canary_token({
"uuid": "tok-w1", "kind": "http", "decky_name": "web1",
"generator": "env_file", "placement_path": "/x",
"callback_token": "slug-W1", "secret_seed": "s", "created_by": "u1",
})
sub = bus.subscribe("canary.>")
app = _build_app(repo, bus)
with TestClient(app) as client:
resp = client.get("/c/slug-W1", headers={"User-Agent": "curl/8.0"})
assert resp.status_code == 200
assert resp.headers["content-type"].startswith("image/gif")
assert resp.headers.get("server") == "nginx"
event = await asyncio.wait_for(sub.__anext__(), timeout=2.0)
assert event.topic == topics.canary("tok-w1", topics.CANARY_TRIGGERED)
assert event.payload["src_ip"]
assert event.payload["user_agent"] == "curl/8.0"
triggers = await repo.list_canary_triggers("tok-w1")
assert len(triggers) == 1
assert triggers[0]["request_path"] == "/c/slug-W1"
tok = await repo.get_canary_token("tok-w1")
assert tok["trigger_count"] == 1
@pytest.mark.asyncio
async def test_unknown_slug_returns_same_response_but_persists_nothing(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
app = _build_app(repo, bus)
with TestClient(app) as client:
resp = client.get("/c/unknown-slug")
assert resp.status_code == 200
assert resp.headers["content-type"].startswith("image/gif")
# No tokens, no triggers, no nothing.
assert await repo.list_canary_tokens() == []
@pytest.mark.asyncio
async def test_root_returns_404(repo: SQLiteRepository, bus: FakeBus) -> None:
app = _build_app(repo, bus)
with TestClient(app) as client:
resp = client.get("/")
assert resp.status_code == 404
@pytest.mark.asyncio
async def test_xff_is_honored(repo: SQLiteRepository, bus: FakeBus) -> None:
await repo.create_canary_token({
"uuid": "tok-xff", "kind": "http", "decky_name": "web1",
"generator": "env_file", "placement_path": "/x",
"callback_token": "slug-xff", "secret_seed": "s", "created_by": "u1",
})
app = _build_app(repo, bus)
with TestClient(app) as client:
client.get("/c/slug-xff", headers={"X-Forwarded-For": "9.9.9.9, 10.0.0.1"})
triggers = await repo.list_canary_triggers("tok-xff")
assert triggers[0]["src_ip"] == "9.9.9.9"
@pytest.mark.asyncio
async def test_fingerprint_query_param_decoded_into_raw_headers(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
"""``?d=<b64url(json)>`` is decoded into raw_headers["_fp"] as a dict."""
import base64
import json
await repo.create_canary_token({
"uuid": "tok-fp1", "kind": "http", "decky_name": "web1",
"generator": "fingerprint_html", "placement_path": "/x",
"callback_token": "slug-FP1", "secret_seed": "s", "created_by": "u1",
})
fp = {"mint": "abc-123", "nav": {"ua": "Test/1.0"}, "id": "h" * 64}
blob = base64.urlsafe_b64encode(json.dumps(fp).encode()).rstrip(b"=").decode()
app = _build_app(repo, bus)
with TestClient(app) as client:
client.get(f"/c/slug-FP1?d={blob}")
triggers = await repo.list_canary_triggers("tok-fp1")
headers = json.loads(triggers[0]["raw_headers"])
assert headers["_fp"] == fp
@pytest.mark.asyncio
async def test_bare_open_beacon_records_fp_open_flag(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
import json
await repo.create_canary_token({
"uuid": "tok-fp2", "kind": "http", "decky_name": "web1",
"generator": "fingerprint_html", "placement_path": "/x",
"callback_token": "slug-FP2", "secret_seed": "s", "created_by": "u1",
})
app = _build_app(repo, bus)
with TestClient(app) as client:
client.get("/c/slug-FP2?o=1")
triggers = await repo.list_canary_triggers("tok-fp2")
headers = json.loads(triggers[0]["raw_headers"])
assert headers["_fp_open"] == "1"
@pytest.mark.asyncio
async def test_chunked_fingerprint_stores_metadata(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
import json
await repo.create_canary_token({
"uuid": "tok-fp3", "kind": "http", "decky_name": "web1",
"generator": "fingerprint_html", "placement_path": "/x",
"callback_token": "slug-FP3", "secret_seed": "s", "created_by": "u1",
})
app = _build_app(repo, bus)
with TestClient(app) as client:
client.get("/c/slug-FP3?s=abc&i=0&n=2&d=Zm9vYmFy")
triggers = await repo.list_canary_triggers("tok-fp3")
headers = json.loads(triggers[0]["raw_headers"])
assert headers["_fp_sid"] == "abc"
assert headers["_fp_idx"] == "0"
assert headers["_fp_total"] == "2"
assert headers["_fp_chunk"] == "Zm9vYmFy"
# Single-shot decode should NOT have run for a chunked payload.
assert "_fp" not in headers
@pytest.mark.asyncio
async def test_malformed_fingerprint_records_decode_error(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
import json
await repo.create_canary_token({
"uuid": "tok-fp4", "kind": "http", "decky_name": "web1",
"generator": "fingerprint_html", "placement_path": "/x",
"callback_token": "slug-FP4", "secret_seed": "s", "created_by": "u1",
})
app = _build_app(repo, bus)
with TestClient(app) as client:
# base64-decodable but not JSON
client.get("/c/slug-FP4?d=Zm9vYmFy") # "foobar"
triggers = await repo.list_canary_triggers("tok-fp4")
headers = json.loads(triggers[0]["raw_headers"])
assert headers["_fp_decode_error"] == "1"
assert "_fp" not in headers
@pytest.mark.asyncio
async def test_oversize_fingerprint_dropped(
repo: SQLiteRepository, bus: FakeBus,
) -> None:
import json
await repo.create_canary_token({
"uuid": "tok-fp5", "kind": "http", "decky_name": "web1",
"generator": "fingerprint_html", "placement_path": "/x",
"callback_token": "slug-FP5", "secret_seed": "s", "created_by": "u1",
})
app = _build_app(repo, bus)
with TestClient(app) as client:
# 9KB blob exceeds the 8KB per-chunk cap
client.get("/c/slug-FP5?d=" + "A" * (9 * 1024))
triggers = await repo.list_canary_triggers("tok-fp5")
headers = json.loads(triggers[0]["raw_headers"])
assert headers["_fp_oversize"] == "1"
assert "_fp" not in headers
@pytest.mark.asyncio
async def test_no_decnet_strings_in_response(repo: SQLiteRepository, bus: FakeBus) -> None:
"""Stealth posture: nothing in the HTTP surface mentions DECNET."""
app = _build_app(repo, bus)
with TestClient(app) as client:
resp = client.get("/c/anything")
body = resp.content.lower()
for v in resp.headers.values():
assert b"decnet" not in v.lower().encode()
assert b"decnet" not in body
# Docs / openapi / redoc are disabled.
assert client.get("/docs").status_code == 404
assert client.get("/openapi.json").status_code == 404
assert client.get("/redoc").status_code == 404