anti
698ecaa322
Stateless JWTs had no revocation path: a stolen token stayed valid for its full 24h even after the victim changed their password, and there was no logout. This lays the foundation for revoking them. - User.tokens_valid_from: per-user bulk-revocation cutoff (compared against the token's iat). RevokedToken(jti PK, exp): single-token denylist, pruned opportunistically on insert so it never outgrows live-but-revoked tokens. - login() now mints a jti; create_access_token already stamps iat/exp. - repo.revoke_token / is_token_revoked / set_tokens_valid_from (abstract + shared sqlmodel impl + DummyRepo coverage stubs). - Centralized validate path in dependencies.py: every auth dependency now resolves the user and fails closed on (1) missing jti (legacy/pre-deploy token -> one forced re-login), (2) iat before the cutoff, (3) a denylisted jti. Denylist lookups ride a 10s membership cache mirroring the user cache. - Contract/fuzz harness seeds its fixed-uuid principal under DECNET_CONTRACT_TEST so its minted token resolves to a live admin user.
312 lines
12 KiB
Python
312 lines
12 KiB
Python
# SPDX-License-Identifier: AGPL-3.0-or-later
|
|
import asyncio
|
|
import time
|
|
from datetime import datetime, timezone
|
|
from typing import Any, Optional
|
|
|
|
import jwt
|
|
from fastapi import HTTPException, status, Request
|
|
from fastapi.security import OAuth2PasswordBearer
|
|
|
|
from decnet.web.auth import ALGORITHM, SECRET_KEY
|
|
from decnet.web.db.repository import BaseRepository
|
|
from decnet.web.db.factory import get_repository
|
|
|
|
# Shared repository singleton
|
|
_repo: Optional[BaseRepository] = None
|
|
|
|
def get_repo() -> BaseRepository:
|
|
"""FastAPI dependency to inject the configured repository."""
|
|
global _repo
|
|
if _repo is None:
|
|
_repo = get_repository()
|
|
return _repo
|
|
|
|
repo = get_repo()
|
|
|
|
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/v1/auth/login")
|
|
|
|
|
|
# Per-request user lookup was the hidden tax behind every authed endpoint —
|
|
# SELECT users WHERE uuid=? ran once per call, serializing through aiosqlite.
|
|
# 10s TTL is well below JWT expiry and we invalidate on all user writes.
|
|
_USER_TTL = 10.0
|
|
_user_cache: dict[str, tuple[Optional[dict[str, Any]], float]] = {}
|
|
_user_cache_lock: Optional[asyncio.Lock] = None
|
|
|
|
# Username cache for the login hot path. Short TTL — the bcrypt verify
|
|
# still runs against the cached hash, so security is unchanged. The
|
|
# staleness window is: if a password is changed, the old password is
|
|
# usable for up to _USERNAME_TTL seconds until the cache expires (or
|
|
# invalidate_user_cache fires). We invalidate on every user write.
|
|
# Missing lookups are NOT cached to avoid locking out a just-created user.
|
|
_USERNAME_TTL = 5.0
|
|
_username_cache: dict[str, tuple[dict[str, Any], float]] = {}
|
|
_username_cache_lock: Optional[asyncio.Lock] = None
|
|
|
|
# Denylist membership cache for revoked jti lookups. Same 10s envelope as the
|
|
# user cache: a token revoked elsewhere stops working within _REVOKED_TTL. In
|
|
# this process we drop the stale entry on revoke (see invalidate_token_cache),
|
|
# so logout is immediate locally; the TTL only bounds cross-worker staleness.
|
|
_REVOKED_TTL = 10.0
|
|
_revoked_cache: dict[str, tuple[bool, float]] = {}
|
|
_revoked_cache_lock: Optional[asyncio.Lock] = None
|
|
|
|
|
|
def _reset_user_cache() -> None:
|
|
global _user_cache, _user_cache_lock, _username_cache, _username_cache_lock
|
|
global _revoked_cache, _revoked_cache_lock
|
|
_user_cache = {}
|
|
_user_cache_lock = None
|
|
_username_cache = {}
|
|
_username_cache_lock = None
|
|
_revoked_cache = {}
|
|
_revoked_cache_lock = None
|
|
|
|
|
|
def invalidate_user_cache(user_uuid: Optional[str] = None) -> None:
|
|
"""Drop a single user (or all users) from the auth caches.
|
|
|
|
Callers: password change, role change, user create/delete.
|
|
The username cache is always cleared wholesale — we don't track
|
|
uuid→username and user writes are rare, so the cost is trivial.
|
|
"""
|
|
if user_uuid is None:
|
|
_user_cache.clear()
|
|
else:
|
|
_user_cache.pop(user_uuid, None)
|
|
_username_cache.clear()
|
|
|
|
|
|
def invalidate_token_cache(jti: Optional[str] = None) -> None:
|
|
"""Drop a single jti (or the whole denylist cache) so the next request
|
|
re-reads revocation state from the DB. Called right after ``revoke_token``
|
|
so a logged-out token stops working immediately in this process."""
|
|
if jti is None:
|
|
_revoked_cache.clear()
|
|
else:
|
|
_revoked_cache.pop(jti, None)
|
|
|
|
|
|
async def get_user_by_username_cached(username: str) -> Optional[dict[str, Any]]:
|
|
"""Cached read of get_user_by_username for the login path.
|
|
|
|
Positive hits are cached for _USERNAME_TTL seconds. Misses bypass
|
|
the cache so a freshly-created user can log in immediately.
|
|
"""
|
|
global _username_cache_lock
|
|
entry = _username_cache.get(username)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _USERNAME_TTL:
|
|
return entry[0]
|
|
if _username_cache_lock is None:
|
|
_username_cache_lock = asyncio.Lock()
|
|
async with _username_cache_lock:
|
|
entry = _username_cache.get(username)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _USERNAME_TTL:
|
|
return entry[0]
|
|
user = await repo.get_user_by_username(username)
|
|
if user is not None:
|
|
_username_cache[username] = (user, time.monotonic())
|
|
return user
|
|
|
|
|
|
async def _get_user_cached(user_uuid: str) -> Optional[dict[str, Any]]:
|
|
global _user_cache_lock
|
|
entry = _user_cache.get(user_uuid)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _USER_TTL:
|
|
return entry[0]
|
|
if _user_cache_lock is None:
|
|
_user_cache_lock = asyncio.Lock()
|
|
async with _user_cache_lock:
|
|
entry = _user_cache.get(user_uuid)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _USER_TTL:
|
|
return entry[0]
|
|
user = await repo.get_user_by_uuid(user_uuid)
|
|
_user_cache[user_uuid] = (user, time.monotonic())
|
|
return user
|
|
|
|
|
|
async def _is_revoked_cached(jti: str) -> bool:
|
|
global _revoked_cache_lock
|
|
entry = _revoked_cache.get(jti)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _REVOKED_TTL:
|
|
return entry[0]
|
|
if _revoked_cache_lock is None:
|
|
_revoked_cache_lock = asyncio.Lock()
|
|
async with _revoked_cache_lock:
|
|
entry = _revoked_cache.get(jti)
|
|
now = time.monotonic()
|
|
if entry is not None and now - entry[1] < _REVOKED_TTL:
|
|
return entry[0]
|
|
revoked = await repo.is_token_revoked(jti)
|
|
_revoked_cache[jti] = (revoked, time.monotonic())
|
|
return revoked
|
|
|
|
|
|
_CREDENTIALS_EXCEPTION = HTTPException(
|
|
status_code=status.HTTP_401_UNAUTHORIZED,
|
|
detail="Could not validate credentials",
|
|
headers={"WWW-Authenticate": "Bearer"},
|
|
)
|
|
|
|
|
|
def _epoch(value: Any) -> float:
|
|
"""Coerce a JWT ``iat`` (int seconds) or a stored datetime to UTC epoch
|
|
seconds so the two can be compared regardless of source. Naive datetimes
|
|
(SQLite round-trips lose tzinfo) are treated as the UTC we wrote."""
|
|
if isinstance(value, (int, float)):
|
|
return float(value)
|
|
if isinstance(value, datetime):
|
|
aware = value.replace(tzinfo=timezone.utc) if value.tzinfo is None else value
|
|
return aware.timestamp()
|
|
raise _CREDENTIALS_EXCEPTION
|
|
|
|
|
|
def _decode_payload(token: str) -> dict[str, Any]:
|
|
"""Decode + signature/expiry-verify a raw JWT, or raise 401."""
|
|
try:
|
|
payload: dict[str, Any] = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
|
|
except jwt.PyJWTError:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
if payload.get("uuid") is None:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
return payload
|
|
|
|
|
|
async def _resolve_token(token: str) -> tuple[str, dict[str, Any]]:
|
|
"""Decode a token, load its user, and enforce revocation. Returns
|
|
``(user_uuid, user_dict)`` or raises 401. Single chokepoint so every auth
|
|
path (header, SSE query param, role gates) shares identical revocation
|
|
semantics."""
|
|
payload = _decode_payload(token)
|
|
user_uuid: str = payload["uuid"]
|
|
user = await _get_user_cached(user_uuid)
|
|
if not user:
|
|
# Unknown / deleted user — also covers the user-delete revocation case.
|
|
raise _CREDENTIALS_EXCEPTION
|
|
# 1. Legacy tokens minted before jti existed cannot be revoked — fail closed
|
|
# so a deploy of this feature forces exactly one re-login.
|
|
jti = payload.get("jti")
|
|
if not jti:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
# 2. Bulk cutoff: password/role change moves tokens_valid_from forward.
|
|
cutoff = user.get("tokens_valid_from")
|
|
if cutoff is not None and _epoch(payload.get("iat", 0)) < _epoch(cutoff):
|
|
raise _CREDENTIALS_EXCEPTION
|
|
# 3. Single-token denylist (logout).
|
|
if await _is_revoked_cached(jti):
|
|
raise _CREDENTIALS_EXCEPTION
|
|
return user_uuid, user
|
|
|
|
|
|
def _bearer_from_header(request: Request) -> Optional[str]:
|
|
auth = request.headers.get("Authorization")
|
|
if auth and auth.startswith("Bearer "):
|
|
return auth.split(" ", 1)[1]
|
|
return None
|
|
|
|
|
|
async def _resolve_request(request: Request) -> tuple[str, dict[str, Any]]:
|
|
"""Bearer-header variant of :func:`_resolve_token`."""
|
|
token = _bearer_from_header(request)
|
|
if not token:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
return await _resolve_token(token)
|
|
|
|
|
|
def get_token_claims(request: Request) -> dict[str, Any]:
|
|
"""Return the validated claims of the presented Bearer token (decode +
|
|
signature + revocation checks). Used by logout, which needs the token's own
|
|
``jti``/``exp`` to denylist *this* session even for must_change users."""
|
|
token = _bearer_from_header(request)
|
|
if not token:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
return _decode_payload(token)
|
|
|
|
|
|
async def get_stream_user(request: Request, token: Optional[str] = None) -> str:
|
|
"""Auth dependency for SSE endpoints — accepts Bearer header OR ?token= query param.
|
|
EventSource does not support custom headers, so the query-string fallback is intentional here only.
|
|
"""
|
|
resolved = _bearer_from_header(request) or token
|
|
if not resolved:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
# Decode-only: returns the uuid. Revocation/role enforcement happens in
|
|
# require_stream_role (the sole production caller), which runs the full
|
|
# _resolve_token path. Kept thin so its decode contract stays unit-testable.
|
|
return _decode_payload(resolved)["uuid"]
|
|
|
|
|
|
async def get_current_user(request: Request) -> str:
|
|
"""Auth dependency — enforces must_change_password."""
|
|
_user_uuid, _user = await _resolve_request(request)
|
|
if _user.get("must_change_password"):
|
|
raise HTTPException(
|
|
status_code=status.HTTP_403_FORBIDDEN,
|
|
detail="Password change required before accessing this resource",
|
|
)
|
|
return _user_uuid
|
|
|
|
|
|
async def get_current_user_unchecked(request: Request) -> str:
|
|
"""Auth dependency — skips must_change_password enforcement (but still
|
|
enforces signature, user existence, and revocation).
|
|
Use only for endpoints that must remain reachable with the flag set (e.g. change-password).
|
|
"""
|
|
_user_uuid, _user = await _resolve_request(request)
|
|
return _user_uuid
|
|
|
|
|
|
# ---------------------------------------------------------------------------
|
|
# Role-based access control
|
|
# ---------------------------------------------------------------------------
|
|
|
|
def require_role(*allowed_roles: str):
|
|
"""Factory that returns a FastAPI dependency enforcing role membership.
|
|
|
|
Inlines JWT decode + user lookup + must_change_password + role check so the
|
|
user is only loaded from the DB once per request (not once in
|
|
``get_current_user`` and again here). Returns the full user dict so
|
|
endpoints can inspect ``user["uuid"]``, ``user["role"]``, etc.
|
|
"""
|
|
async def _check(request: Request) -> dict:
|
|
_user_uuid, user = await _resolve_request(request)
|
|
if user.get("must_change_password"):
|
|
raise HTTPException(
|
|
status_code=status.HTTP_403_FORBIDDEN,
|
|
detail="Password change required before accessing this resource",
|
|
)
|
|
if user["role"] not in allowed_roles:
|
|
raise HTTPException(
|
|
status_code=status.HTTP_403_FORBIDDEN,
|
|
detail="Insufficient permissions",
|
|
)
|
|
return user
|
|
return _check
|
|
|
|
|
|
def require_stream_role(*allowed_roles: str):
|
|
"""Like ``require_role`` but for SSE endpoints that accept a query-param token."""
|
|
async def _check(request: Request, token: Optional[str] = None) -> dict:
|
|
resolved = _bearer_from_header(request) or token
|
|
if not resolved:
|
|
raise _CREDENTIALS_EXCEPTION
|
|
_user_uuid, user = await _resolve_token(resolved)
|
|
if user["role"] not in allowed_roles:
|
|
raise HTTPException(
|
|
status_code=status.HTTP_403_FORBIDDEN,
|
|
detail="Insufficient permissions",
|
|
)
|
|
return user
|
|
return _check
|
|
|
|
|
|
require_admin = require_role("admin")
|
|
require_viewer = require_role("viewer", "admin")
|
|
require_stream_viewer = require_stream_role("viewer", "admin")
|