Phase 1: Add passkey (WebAuthn/FIDO2) backend

New files:
- models/passkey_credential.py: PasskeyCredential model with indexed credential_id
- alembic 061: Create passkey_credentials table
- services/passkey.py: Challenge token management (itsdangerous + nonce replay
  protection) and py_webauthn wrappers for registration/authentication
- routers/passkeys.py: 6 endpoints (register begin/complete, login begin/complete,
  list, delete) with full security hardening

Changes:
- config.py: WEBAUTHN_RP_ID, RP_NAME, ORIGIN, CHALLENGE_TTL settings
- main.py: Mount passkey router, add CSRF exemptions for login endpoints
- auth.py: Add has_passkeys to /auth/status response
- nginx.conf: Rate limiting on all passkey endpoints, Permissions-Policy
  updated for publickey-credentials-get/create
- requirements.txt: Add webauthn>=2.1.0

Security: password re-entry for registration (V-02), single-use nonce
challenges (V-01), constant-time login/begin (V-03), shared lockout
counter, generic 401 errors, audit logging on all events.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
Kyle 2026-03-17 22:46:00 +08:00
parent eebb34aa77
commit e8e3f62ff8
10 changed files with 794 additions and 2 deletions

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@ -0,0 +1,40 @@
"""Add passkey_credentials table for WebAuthn/FIDO2 authentication
Revision ID: 061
Revises: 060
"""
import sqlalchemy as sa
from alembic import op
revision = "061"
down_revision = "060"
branch_labels = None
depends_on = None
def upgrade():
op.create_table(
"passkey_credentials",
sa.Column("id", sa.Integer, primary_key=True),
sa.Column(
"user_id",
sa.Integer,
sa.ForeignKey("users.id", ondelete="CASCADE"),
nullable=False,
),
sa.Column("credential_id", sa.Text, unique=True, nullable=False),
sa.Column("public_key", sa.Text, nullable=False),
sa.Column("sign_count", sa.Integer, nullable=False, server_default="0"),
sa.Column("name", sa.String(100), nullable=False),
sa.Column("transports", sa.Text, nullable=True),
sa.Column("backed_up", sa.Boolean, nullable=False, server_default="false"),
sa.Column("created_at", sa.DateTime, server_default=sa.text("now()")),
sa.Column("last_used_at", sa.DateTime, nullable=True),
)
op.create_index(
"ix_passkey_credentials_user_id", "passkey_credentials", ["user_id"]
)
def downgrade():
op.drop_table("passkey_credentials")

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@ -30,6 +30,12 @@ class Settings(BaseSettings):
# Concurrent session limit per user (oldest evicted when exceeded)
MAX_SESSIONS_PER_USER: int = 10
# WebAuthn / Passkey configuration
WEBAUTHN_RP_ID: str = "localhost" # eTLD+1 domain, e.g. "umbra.ghost6.xyz"
WEBAUTHN_RP_NAME: str = "UMBRA"
WEBAUTHN_ORIGIN: str = "http://localhost" # Full origin with scheme, e.g. "https://umbra.ghost6.xyz"
WEBAUTHN_CHALLENGE_TTL: int = 60 # Challenge token lifetime in seconds
model_config = SettingsConfigDict(
env_file=".env",
env_file_encoding="utf-8",
@ -47,6 +53,9 @@ class Settings(BaseSettings):
self.CORS_ORIGINS = "http://localhost:5173"
assert self.COOKIE_SECURE is not None # type narrowing
assert self.CORS_ORIGINS is not None
# Validate WebAuthn origin includes scheme (S-04)
if not self.WEBAUTHN_ORIGIN.startswith(("http://", "https://")):
raise ValueError("WEBAUTHN_ORIGIN must include scheme (http:// or https://)")
return self

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@ -7,7 +7,7 @@ from apscheduler.schedulers.asyncio import AsyncIOScheduler
from app.config import settings
from app.database import engine
from app.routers import auth, todos, events, calendars, reminders, projects, people, locations, settings as settings_router, dashboard, weather, event_templates
from app.routers import totp, admin, notifications as notifications_router, connections as connections_router, shared_calendars as shared_calendars_router, event_invitations as event_invitations_router
from app.routers import totp, admin, notifications as notifications_router, connections as connections_router, shared_calendars as shared_calendars_router, event_invitations as event_invitations_router, passkeys as passkeys_router
from app.jobs.notifications import run_notification_dispatch
# Import models so Alembic's autogenerate can discover them
@ -23,6 +23,7 @@ from app.models import user_connection as _user_connection_model # noqa: F401
from app.models import calendar_member as _calendar_member_model # noqa: F401
from app.models import event_lock as _event_lock_model # noqa: F401
from app.models import event_invitation as _event_invitation_model # noqa: F401
from app.models import passkey_credential as _passkey_credential_model # noqa: F401
# ---------------------------------------------------------------------------
@ -49,6 +50,8 @@ class CSRFHeaderMiddleware:
"/api/auth/totp-verify",
"/api/auth/totp/enforce-setup",
"/api/auth/totp/enforce-confirm",
"/api/auth/passkeys/login/begin",
"/api/auth/passkeys/login/complete",
})
_MUTATING_METHODS = frozenset({"POST", "PUT", "PATCH", "DELETE"})
@ -134,6 +137,7 @@ app.include_router(dashboard.router, prefix="/api", tags=["Dashboard"])
app.include_router(weather.router, prefix="/api/weather", tags=["Weather"])
app.include_router(event_templates.router, prefix="/api/event-templates", tags=["Event Templates"])
app.include_router(totp.router, prefix="/api/auth", tags=["TOTP MFA"])
app.include_router(passkeys_router.router, prefix="/api/auth/passkeys", tags=["Passkeys"])
app.include_router(admin.router, prefix="/api/admin", tags=["Admin"])
app.include_router(notifications_router.router, prefix="/api/notifications", tags=["Notifications"])
app.include_router(connections_router.router, prefix="/api/connections", tags=["Connections"])

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@ -23,6 +23,7 @@ from app.models.event_lock import EventLock
from app.models.event_invitation import EventInvitation, EventInvitationOverride
from app.models.project_member import ProjectMember
from app.models.project_task_assignment import ProjectTaskAssignment
from app.models.passkey_credential import PasskeyCredential
__all__ = [
"Settings",
@ -51,4 +52,5 @@ __all__ = [
"EventInvitationOverride",
"ProjectMember",
"ProjectTaskAssignment",
"PasskeyCredential",
]

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@ -0,0 +1,30 @@
from datetime import datetime
from sqlalchemy import Boolean, ForeignKey, Integer, String, Text, func
from sqlalchemy.orm import Mapped, mapped_column
from app.database import Base
class PasskeyCredential(Base):
__tablename__ = "passkey_credentials"
id: Mapped[int] = mapped_column(primary_key=True)
user_id: Mapped[int] = mapped_column(
Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True
)
# base64url-encoded credential ID (spec allows up to 1023 bytes → ~1363 chars)
credential_id: Mapped[str] = mapped_column(Text, unique=True, nullable=False)
# base64url-encoded COSE public key
public_key: Mapped[str] = mapped_column(Text, nullable=False)
# Authenticator sign count for clone detection
sign_count: Mapped[int] = mapped_column(Integer, default=0)
# User-assigned label (e.g. "MacBook Pro — Chrome")
name: Mapped[str] = mapped_column(String(100), nullable=False)
# JSON array of transport hints (e.g. '["usb","hybrid"]')
transports: Mapped[str | None] = mapped_column(Text, nullable=True)
# Whether the credential is backed up / synced across devices
backed_up: Mapped[bool] = mapped_column(Boolean, default=False)
created_at: Mapped[datetime] = mapped_column(default=func.now())
last_used_at: Mapped[datetime | None] = mapped_column(nullable=True)

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@ -29,6 +29,7 @@ from app.models.user import User
from app.models.session import UserSession
from app.models.settings import Settings
from app.models.system_config import SystemConfig
from app.models.passkey_credential import PasskeyCredential
from app.models.calendar import Calendar
from app.schemas.auth import (
SetupRequest, LoginRequest, RegisterRequest,
@ -513,6 +514,16 @@ async def auth_status(
config = config_result.scalar_one_or_none()
registration_open = config.allow_registration if config else False
# Check if authenticated user has passkeys registered (Q-04)
has_passkeys = False
if authenticated and u:
pk_result = await db.execute(
select(func.count()).select_from(PasskeyCredential).where(
PasskeyCredential.user_id == u.id
)
)
has_passkeys = pk_result.scalar_one() > 0
return {
"authenticated": authenticated,
"setup_required": setup_required,
@ -520,6 +531,7 @@ async def auth_status(
"username": u.username if authenticated and u else None,
"registration_open": registration_open,
"is_locked": is_locked,
"has_passkeys": has_passkeys,
}

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@ -0,0 +1,451 @@
"""
Passkey (WebAuthn/FIDO2) router.
Endpoints (all under /api/auth/passkeys registered in main.py):
POST /register/begin Start passkey registration (auth + password required)
POST /register/complete Complete registration ceremony (auth required)
POST /login/begin Start passkey authentication (public, CSRF-exempt)
POST /login/complete Complete authentication ceremony (public, CSRF-exempt)
GET / List registered passkeys (auth required)
DELETE /{id} Remove a passkey (auth + password required)
Security:
- Challenge tokens signed with itsdangerous (60s TTL, single-use nonce)
- Registration binds challenge to user_id, validated on complete (S-01)
- Registration requires password re-entry (V-02)
- Generic 401 on all auth failures (no credential enumeration)
- Constant-time response on login/begin (V-03)
- Failed passkey logins increment shared lockout counter
- Passkey login bypasses TOTP (passkey IS 2FA)
"""
import asyncio
import json
import logging
from datetime import datetime
from fastapi import APIRouter, Depends, HTTPException, Request, Response
from pydantic import BaseModel, ConfigDict, Field
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from app.database import get_db
from app.models.user import User
from app.models.passkey_credential import PasskeyCredential
from app.routers.auth import get_current_user
from app.services.audit import get_client_ip, log_audit_event
from app.services.auth import averify_password_with_upgrade
from app.services.session import (
create_db_session,
set_session_cookie,
check_account_lockout,
record_failed_login,
record_successful_login,
)
from app.services.passkey import (
create_challenge_token,
verify_challenge_token,
build_registration_options,
verify_registration as verify_registration_response_svc,
build_authentication_options,
verify_authentication as verify_authentication_response_svc,
)
from webauthn.helpers import bytes_to_base64url, base64url_to_bytes
logger = logging.getLogger(__name__)
router = APIRouter()
# ---------------------------------------------------------------------------
# Request/Response schemas
# ---------------------------------------------------------------------------
class PasskeyRegisterBeginRequest(BaseModel):
model_config = ConfigDict(extra="forbid")
password: str = Field(max_length=128)
class PasskeyRegisterCompleteRequest(BaseModel):
model_config = ConfigDict(extra="forbid")
credential: str = Field(max_length=8192)
challenge_token: str = Field(max_length=2048)
name: str = Field(min_length=1, max_length=100)
class PasskeyLoginBeginRequest(BaseModel):
model_config = ConfigDict(extra="forbid")
username: str | None = Field(None, max_length=50)
class PasskeyLoginCompleteRequest(BaseModel):
model_config = ConfigDict(extra="forbid")
credential: str = Field(max_length=8192)
challenge_token: str = Field(max_length=2048)
class PasskeyDeleteRequest(BaseModel):
model_config = ConfigDict(extra="forbid")
password: str = Field(max_length=128)
# ---------------------------------------------------------------------------
# Registration endpoints (authenticated)
# ---------------------------------------------------------------------------
@router.post("/register/begin")
async def passkey_register_begin(
data: PasskeyRegisterBeginRequest,
db: AsyncSession = Depends(get_db),
current_user: User = Depends(get_current_user),
):
"""Start passkey registration. Requires password re-entry (V-02)."""
# V-02: Verify password before allowing registration
valid, new_hash = await averify_password_with_upgrade(
data.password, current_user.password_hash
)
if not valid:
raise HTTPException(status_code=401, detail="Invalid password")
if new_hash:
current_user.password_hash = new_hash
await db.commit()
# Load existing credential IDs for exclusion
result = await db.execute(
select(PasskeyCredential.credential_id).where(
PasskeyCredential.user_id == current_user.id
)
)
existing_ids = [
base64url_to_bytes(row[0]) for row in result.all()
]
options_json, challenge = build_registration_options(
user_id=current_user.id,
username=current_user.username,
existing_credential_ids=existing_ids,
)
token = create_challenge_token(challenge, user_id=current_user.id)
return {
"options": json.loads(options_json),
"challenge_token": token,
}
@router.post("/register/complete")
async def passkey_register_complete(
data: PasskeyRegisterCompleteRequest,
request: Request,
db: AsyncSession = Depends(get_db),
current_user: User = Depends(get_current_user),
):
"""Complete passkey registration ceremony."""
# Verify challenge token — cross-check user binding (S-01) + single-use nonce (V-01)
challenge = verify_challenge_token(
data.challenge_token, expected_user_id=current_user.id
)
if challenge is None:
raise HTTPException(status_code=401, detail="Invalid or expired challenge")
try:
verified = verify_registration_response_svc(
credential_json=data.credential,
challenge=challenge,
)
except Exception as e:
logger.warning("Passkey registration verification failed: %s", e)
raise HTTPException(status_code=400, detail="Registration verification failed")
# Store credential
credential_id_b64 = bytes_to_base64url(verified.credential_id)
# Check for duplicate (race condition safety)
existing = await db.execute(
select(PasskeyCredential).where(
PasskeyCredential.credential_id == credential_id_b64
)
)
if existing.scalar_one_or_none():
raise HTTPException(status_code=409, detail="Credential already registered")
# Extract transport hints if available
transports_json = None
if hasattr(verified, 'credential_device_type'):
pass # py_webauthn doesn't expose transports on VerifiedRegistration
# Transports come from the browser response — parse from credential JSON
try:
cred_data = json.loads(data.credential)
if "response" in cred_data and "transports" in cred_data["response"]:
transports_json = json.dumps(cred_data["response"]["transports"])
except (json.JSONDecodeError, KeyError):
pass
# Determine backup state from py_webauthn flags
backed_up = getattr(verified, 'credential_backed_up', False)
new_credential = PasskeyCredential(
user_id=current_user.id,
credential_id=credential_id_b64,
public_key=bytes_to_base64url(verified.credential_public_key),
sign_count=verified.sign_count,
name=data.name,
transports=transports_json,
backed_up=backed_up,
)
db.add(new_credential)
# B-02: If user has mfa_enforce_pending, clear it (passkey = MFA)
if current_user.mfa_enforce_pending:
current_user.mfa_enforce_pending = False
# Extract response data BEFORE commit (ORM expiry rule)
response_data = {
"id": None, # will be set after flush
"name": new_credential.name,
"created_at": None,
"backed_up": backed_up,
}
await db.flush()
response_data["id"] = new_credential.id
response_data["created_at"] = str(new_credential.created_at) if new_credential.created_at else None
await log_audit_event(
db, action="passkey.registered", actor_id=current_user.id,
detail={"credential_name": data.name},
ip=get_client_ip(request),
)
await db.commit()
return response_data
# ---------------------------------------------------------------------------
# Authentication endpoints (unauthenticated — CSRF-exempt)
# ---------------------------------------------------------------------------
@router.post("/login/begin")
async def passkey_login_begin(
data: PasskeyLoginBeginRequest,
db: AsyncSession = Depends(get_db),
):
"""Start passkey authentication. CSRF-exempt, public endpoint."""
credential_data = None
if data.username:
# Look up user's credentials for allowCredentials
result = await db.execute(
select(User).where(User.username == data.username.lower().strip())
)
user = result.scalar_one_or_none()
if user:
cred_result = await db.execute(
select(
PasskeyCredential.credential_id,
PasskeyCredential.transports,
).where(PasskeyCredential.user_id == user.id)
)
rows = cred_result.all()
if rows:
credential_data = []
for row in rows:
cid_bytes = base64url_to_bytes(row[0])
transports = json.loads(row[1]) if row[1] else None
credential_data.append((cid_bytes, transports))
# V-03: Generate options regardless of whether user exists or has passkeys.
# Identical response shape prevents timing enumeration.
options_json, challenge = build_authentication_options(
credential_ids_and_transports=credential_data,
)
token = create_challenge_token(challenge)
return {
"options": json.loads(options_json),
"challenge_token": token,
}
@router.post("/login/complete")
async def passkey_login_complete(
data: PasskeyLoginCompleteRequest,
request: Request,
response: Response,
db: AsyncSession = Depends(get_db),
):
"""Complete passkey authentication. CSRF-exempt, public endpoint."""
# Verify challenge token (60s TTL, single-use nonce V-01)
challenge = verify_challenge_token(data.challenge_token)
if challenge is None:
raise HTTPException(status_code=401, detail="Authentication failed")
# Parse credential_id from browser response
try:
cred_data = json.loads(data.credential)
raw_id_b64 = cred_data.get("rawId") or cred_data.get("id", "")
except (json.JSONDecodeError, KeyError):
raise HTTPException(status_code=401, detail="Authentication failed")
# Look up credential by ID
result = await db.execute(
select(PasskeyCredential).where(
PasskeyCredential.credential_id == raw_id_b64
)
)
credential = result.scalar_one_or_none()
if not credential:
raise HTTPException(status_code=401, detail="Authentication failed")
# Load user
user_result = await db.execute(
select(User).where(User.id == credential.user_id)
)
user = user_result.scalar_one_or_none()
if not user:
raise HTTPException(status_code=401, detail="Authentication failed")
# Check account lockout (C-03)
await check_account_lockout(user)
# Check active status (C-03)
if not user.is_active:
raise HTTPException(status_code=401, detail="Authentication failed")
# Verify the authentication response
try:
verified = verify_authentication_response_svc(
credential_json=data.credential,
challenge=challenge,
credential_public_key=base64url_to_bytes(credential.public_key),
credential_current_sign_count=credential.sign_count,
)
except Exception as e:
logger.warning("Passkey authentication verification failed for user %s: %s", user.id, e)
# Increment failed login counter (shared with password auth)
await record_failed_login(db, user)
await log_audit_event(
db, action="passkey.login_failed", actor_id=user.id,
detail={"reason": "verification_failed"},
ip=get_client_ip(request),
)
await db.commit()
raise HTTPException(status_code=401, detail="Authentication failed")
# Update sign count (log anomaly but don't fail — S-05)
new_sign_count = verified.new_sign_count
if new_sign_count < credential.sign_count and credential.sign_count > 0:
logger.warning(
"Sign count anomaly for user %s credential %s: expected >= %d, got %d",
user.id, credential.id, credential.sign_count, new_sign_count,
)
await log_audit_event(
db, action="passkey.sign_count_anomaly", actor_id=user.id,
detail={
"credential_id": credential.id,
"expected": credential.sign_count,
"received": new_sign_count,
},
ip=get_client_ip(request),
)
credential.sign_count = new_sign_count
credential.last_used_at = datetime.now()
# Record successful login
await record_successful_login(db, user)
# Create session (shared service — enforces session cap)
client_ip = get_client_ip(request)
user_agent = request.headers.get("user-agent")
_, token = await create_db_session(db, user, client_ip, user_agent)
set_session_cookie(response, token)
await log_audit_event(
db, action="passkey.login_success", actor_id=user.id,
detail={"credential_name": credential.name},
ip=client_ip,
)
await db.commit()
# B-01: Handle must_change_password and mfa_enforce_pending flags
result_data: dict = {"authenticated": True}
if user.must_change_password:
result_data["must_change_password"] = True
# Passkey satisfies MFA — if mfa_enforce_pending, clear it
if user.mfa_enforce_pending:
user.mfa_enforce_pending = False
await db.commit()
return result_data
# ---------------------------------------------------------------------------
# Management endpoints (authenticated)
# ---------------------------------------------------------------------------
@router.get("/")
async def list_passkeys(
db: AsyncSession = Depends(get_db),
current_user: User = Depends(get_current_user),
):
"""List all passkeys for the current user."""
result = await db.execute(
select(PasskeyCredential)
.where(PasskeyCredential.user_id == current_user.id)
.order_by(PasskeyCredential.created_at.desc())
)
credentials = result.scalars().all()
return [
{
"id": c.id,
"name": c.name,
"created_at": str(c.created_at) if c.created_at else None,
"last_used_at": str(c.last_used_at) if c.last_used_at else None,
"backed_up": c.backed_up,
}
for c in credentials
]
@router.delete("/{credential_id}")
async def delete_passkey(
credential_id: int,
data: PasskeyDeleteRequest,
request: Request,
db: AsyncSession = Depends(get_db),
current_user: User = Depends(get_current_user),
):
"""Delete a passkey. Requires password confirmation (S-06)."""
# Verify password
valid, new_hash = await averify_password_with_upgrade(
data.password, current_user.password_hash
)
if not valid:
raise HTTPException(status_code=401, detail="Invalid password")
if new_hash:
current_user.password_hash = new_hash
# Look up credential — verify ownership (IDOR prevention)
result = await db.execute(
select(PasskeyCredential).where(
PasskeyCredential.id == credential_id,
PasskeyCredential.user_id == current_user.id,
)
)
credential = result.scalar_one_or_none()
if not credential:
raise HTTPException(status_code=404, detail="Passkey not found")
cred_name = credential.name
await db.delete(credential)
await log_audit_event(
db, action="passkey.deleted", actor_id=current_user.id,
detail={"credential_name": cred_name, "credential_db_id": credential_id},
ip=get_client_ip(request),
)
await db.commit()
return {"message": "Passkey removed"}

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@ -0,0 +1,220 @@
"""
Passkey (WebAuthn/FIDO2) service.
Handles challenge token creation/verification (itsdangerous + nonce replay protection)
and wraps py_webauthn library calls for registration and authentication ceremonies.
"""
import base64
import json
import logging
import secrets
import time
import threading
from itsdangerous import URLSafeTimedSerializer, BadSignature, SignatureExpired
from webauthn import (
generate_registration_options,
verify_registration_response,
generate_authentication_options,
verify_authentication_response,
options_to_json,
)
from webauthn.helpers.structs import (
PublicKeyCredentialDescriptor,
AuthenticatorSelectionCriteria,
AuthenticatorTransport,
ResidentKeyRequirement,
UserVerificationRequirement,
AttestationConveyancePreference,
)
from webauthn.helpers import bytes_to_base64url, base64url_to_bytes
from app.config import settings as app_settings
logger = logging.getLogger(__name__)
# ---------------------------------------------------------------------------
# Challenge token management (itsdangerous + nonce replay protection V-01)
# ---------------------------------------------------------------------------
_challenge_serializer = URLSafeTimedSerializer(
secret_key=app_settings.SECRET_KEY,
salt="webauthn-challenge-v1",
)
# Thread-safe nonce cache for single-use enforcement
# Keys: nonce string, Values: expiry timestamp
_used_nonces: dict[str, float] = {}
_nonce_lock = threading.Lock()
def create_challenge_token(challenge: bytes, user_id: int | None = None) -> str:
"""Sign challenge + nonce + optional user_id. Returns opaque token string."""
nonce = secrets.token_urlsafe(16)
payload = {
"ch": base64.b64encode(challenge).decode(),
"n": nonce,
}
if user_id is not None:
payload["uid"] = user_id
return _challenge_serializer.dumps(payload)
def verify_challenge_token(token: str, expected_user_id: int | None = None) -> bytes | None:
"""Verify token (TTL from config), enforce single-use via nonce.
If expected_user_id provided, cross-check user binding (for registration).
Returns challenge bytes or None on failure.
"""
try:
data = _challenge_serializer.loads(
token, max_age=app_settings.WEBAUTHN_CHALLENGE_TTL
)
except (BadSignature, SignatureExpired):
return None
nonce = data.get("n")
if not nonce:
return None
now = time.time()
with _nonce_lock:
# Lazy cleanup of expired nonces
expired = [k for k, v in _used_nonces.items() if v <= now]
for k in expired:
del _used_nonces[k]
# Check for replay
if nonce in _used_nonces:
return None
# Mark nonce as used
_used_nonces[nonce] = now + app_settings.WEBAUTHN_CHALLENGE_TTL
# Cross-check user binding for registration tokens
if expected_user_id is not None:
if data.get("uid") != expected_user_id:
return None
return base64.b64decode(data["ch"])
# ---------------------------------------------------------------------------
# py_webauthn wrappers
# All synchronous — ECDSA P-256 verification is ~0.1ms, faster than executor overhead.
# ---------------------------------------------------------------------------
def build_registration_options(
user_id: int,
username: str,
existing_credential_ids: list[bytes],
) -> tuple[str, bytes]:
"""Generate WebAuthn registration options.
Returns (options_json_str, challenge_bytes).
"""
exclude_credentials = [
PublicKeyCredentialDescriptor(id=cid)
for cid in existing_credential_ids
]
options = generate_registration_options(
rp_id=app_settings.WEBAUTHN_RP_ID,
rp_name=app_settings.WEBAUTHN_RP_NAME,
user_id=str(user_id).encode(),
user_name=username,
attestation=AttestationConveyancePreference.NONE,
authenticator_selection=AuthenticatorSelectionCriteria(
resident_key=ResidentKeyRequirement.PREFERRED,
user_verification=UserVerificationRequirement.PREFERRED,
),
exclude_credentials=exclude_credentials,
timeout=60000,
)
options_json = options_to_json(options)
return options_json, options.challenge
def verify_registration(
credential_json: str,
challenge: bytes,
) -> "VerifiedRegistration":
"""Verify a registration response from the browser.
Returns VerifiedRegistration on success, raises on failure.
"""
from webauthn.helpers.structs import RegistrationCredential
credential = RegistrationCredential.model_validate_json(credential_json)
return verify_registration_response(
credential=credential,
expected_challenge=challenge,
expected_rp_id=app_settings.WEBAUTHN_RP_ID,
expected_origin=app_settings.WEBAUTHN_ORIGIN,
require_user_verification=False,
)
def build_authentication_options(
credential_ids_and_transports: list[tuple[bytes, list[str] | None]] | None = None,
) -> tuple[str, bytes]:
"""Generate WebAuthn authentication options.
If credential_ids_and_transports provided, includes allowCredentials.
Otherwise, allows discoverable credential flow.
Returns (options_json_str, challenge_bytes).
"""
allow_credentials = None
if credential_ids_and_transports:
allow_credentials = []
for cid, transports in credential_ids_and_transports:
transport_list = None
if transports:
transport_list = [
AuthenticatorTransport(t)
for t in transports
if t in [e.value for e in AuthenticatorTransport]
]
allow_credentials.append(
PublicKeyCredentialDescriptor(
id=cid,
transports=transport_list or None,
)
)
options = generate_authentication_options(
rp_id=app_settings.WEBAUTHN_RP_ID,
allow_credentials=allow_credentials,
user_verification=UserVerificationRequirement.PREFERRED,
timeout=60000,
)
options_json = options_to_json(options)
return options_json, options.challenge
def verify_authentication(
credential_json: str,
challenge: bytes,
credential_public_key: bytes,
credential_current_sign_count: int,
) -> "VerifiedAuthentication":
"""Verify an authentication response from the browser.
Returns VerifiedAuthentication on success, raises on failure.
Sign count anomalies are NOT hard-failed caller should log and continue.
"""
from webauthn.helpers.structs import AuthenticationCredential
credential = AuthenticationCredential.model_validate_json(credential_json)
return verify_authentication_response(
credential=credential,
expected_challenge=challenge,
expected_rp_id=app_settings.WEBAUTHN_RP_ID,
expected_origin=app_settings.WEBAUTHN_ORIGIN,
credential_public_key=credential_public_key,
credential_current_sign_count=credential_current_sign_count,
require_user_verification=False,
)

View File

@ -15,3 +15,4 @@ python-dateutil==2.9.0
itsdangerous==2.2.0
httpx==0.27.2
apscheduler==3.10.4
webauthn>=2.1.0

View File

@ -83,6 +83,29 @@ server {
include /etc/nginx/proxy-params.conf;
}
# Passkey authentication rate-limited (C-04)
location /api/auth/passkeys/login/begin {
limit_req zone=auth_limit burst=5 nodelay;
limit_req_status 429;
include /etc/nginx/proxy-params.conf;
}
location /api/auth/passkeys/login/complete {
limit_req zone=auth_limit burst=5 nodelay;
limit_req_status 429;
include /etc/nginx/proxy-params.conf;
}
# Passkey registration authenticated, lower burst
location /api/auth/passkeys/register/begin {
limit_req zone=auth_limit burst=3 nodelay;
limit_req_status 429;
include /etc/nginx/proxy-params.conf;
}
location /api/auth/passkeys/register/complete {
limit_req zone=auth_limit burst=3 nodelay;
limit_req_status 429;
include /etc/nginx/proxy-params.conf;
}
# SEC-14: Rate-limit public registration endpoint
location /api/auth/register {
limit_req zone=register_limit burst=3 nodelay;
@ -164,5 +187,5 @@ server {
add_header Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com; img-src 'self' data:; font-src 'self' https://fonts.gstatic.com; connect-src 'self';" always;
add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
# PT-I03: Restrict unnecessary browser APIs
add_header Permissions-Policy "camera=(), microphone=(), geolocation=(), interest-cohort=()" always;
add_header Permissions-Policy "camera=(), microphone=(), geolocation=(), interest-cohort=(), publickey-credentials-get=*, publickey-credentials-create=*" always;
}