feat(08-06): create backend/api/auth/ package — Task 1

- Create api/auth/shared.py: limiter, all Pydantic request models, _set_refresh_cookie, _user_dict - Create api/auth/tokens.py: register, login, refresh, logout, logout-all, me, quota, preferences handlers - Create api/auth/totp.py: totp/setup, totp/enable, totp DELETE handlers (CR-02, CR-03 preserved) - Create api/auth/password.py: change-password, password-reset, password-reset/confirm handlers (CR-01 preserved) - Create api/auth/__init__.py: router aggregator with prefix=/api/auth; re-exports limiter - Rename auth.py monolith to auth_OLD_REMOVE_IN_TASK_2.py (deleted in Task 2 after tests pass) - All 15 routes confirmed; limiter re-export verified; skip_token_hash calls preserved verbatim
2026-06-10 18:42:27 +02:00
parent a895b1812f
commit 5117e2542a
6 changed files with 1743 additions and 0 deletions
@@ -0,0 +1,449 @@
+"""
+Auth API — token-issuing endpoints.
+
+Handles:
+  POST /register        — new user registration with HIBP check
+  POST /login           — login with optional TOTP/backup-code second factor
+  POST /refresh         — rotate refresh token (httpOnly cookie in/out)
+  POST /logout          — revoke current refresh token, clear cookie
+  POST /logout-all      — revoke all refresh tokens for current user
+  GET  /me              — return current user profile
+  GET  /me/quota        — return current user quota
+  GET  /me/preferences  — return current user preferences
+  PATCH /me/preferences — update current user preferences
+"""
+from __future__ import annotations
+
+import hashlib
+import time
+import uuid
+from typing import Optional
+
+from fastapi import APIRouter, Depends, HTTPException, Request, Response, status
+from sqlalchemy import select
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from db.models import BackupCode, Quota, RefreshToken, User
+from deps.auth import get_current_user
+from deps.db import get_db
+from deps.utils import get_client_ip
+from services import auth as auth_service
+from services.audit import write_audit_log
+from api.auth.shared import (
+    limiter,
+    RegisterRequest,
+    LoginRequest,
+    PreferencesUpdate,
+    _set_refresh_cookie,
+    _user_dict,
+)
+
+router = APIRouter()
+
+
+# ── POST /register ────────────────────────────────────────────────────────────
+
+@router.post("/register", status_code=status.HTTP_201_CREATED)
+@limiter.limit("10/minute")
+async def register(
+    request: Request,
+    body: RegisterRequest,
+    session: AsyncSession = Depends(get_db),
+):
+    """Register a new user account.
+
+    - Validates password strength (min 12 chars, upper, lower, digit, special)
+    - Checks HIBP k-anonymity API for breached passwords
+    - Hashes password with Argon2
+    - Inserts User + Quota rows in a single transaction
+    """
+    # Password strength check
+    try:
+        auth_service.validate_password_strength(body.password)
+    except ValueError as exc:
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc))
+
+    # HIBP breach check
+    if await auth_service.check_hibp(body.password):
+        raise HTTPException(
+            status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
+            detail="This password has appeared in a data breach. Choose a different password.",
+        )
+
+    # Duplicate email/handle check
+    result = await session.execute(
+        select(User).where(
+            (User.email == str(body.email)) | (User.handle == body.handle)
+        )
+    )
+    if result.scalar_one_or_none() is not None:
+        raise HTTPException(
+            status_code=status.HTTP_409_CONFLICT,
+            detail="Email or handle already in use",
+        )
+
+    # Create user and quota
+    user_id = uuid.uuid4()
+    new_user = User(
+        id=user_id,
+        handle=body.handle,
+        email=str(body.email),
+        password_hash=auth_service.hash_password(body.password),
+        role="user",
+        is_active=True,
+        password_must_change=False,
+    )
+    quota = Quota(
+        user_id=user_id,
+        limit_bytes=104857600,  # 100 MB default (STORE-01)
+        used_bytes=0,
+    )
+    try:
+        session.add(new_user)
+        await session.flush()  # persist User before Quota FK
+        session.add(quota)
+        await session.commit()
+        await session.refresh(new_user)
+    except IntegrityError:
+        await session.rollback()
+        raise HTTPException(
+            status_code=status.HTTP_409_CONFLICT,
+            detail="Email or handle already in use",
+        )
+
+    return {
+        "id": str(new_user.id),
+        "handle": new_user.handle,
+        "email": new_user.email,
+        "role": new_user.role,
+        "totp_enabled": new_user.totp_enabled,
+        "created_at": new_user.created_at.isoformat() if new_user.created_at else None,
+    }
+
+
+# ── POST /login ───────────────────────────────────────────────────────────────
+
+@router.post("/login")
+@limiter.limit("10/minute")
+async def login(
+    request: Request,
+    body: LoginRequest,
+    response: Response,
+    session: AsyncSession = Depends(get_db),
+):
+    """Authenticate a user and issue tokens.
+
+    Per-account rate limiting (SEC-02): checks Redis counter keyed by email
+    BEFORE any DB lookup to prevent enumeration timing attacks.
+
+    Three login flows:
+      1. No TOTP enabled: password → tokens
+      2. TOTP enabled, no code provided: requires_totp = True (challenge)
+      3. TOTP enabled, totp_code provided: verify TOTP → tokens
+      4. TOTP enabled, backup_code provided (no totp_code): verify backup → tokens
+    """
+    # Per-account rate limiting (SEC-02)
+    redis_client = request.app.state.redis
+    rate_key = f"login_attempts:{body.email}"
+    count = await redis_client.incr(rate_key)
+    if count == 1:
+        # Set TTL only on first increment (15-minute window)
+        await redis_client.expire(rate_key, 900)
+    if count > 10:
+        raise HTTPException(
+            status_code=status.HTTP_429_TOO_MANY_REQUESTS,
+            detail="Too many login attempts. Try again in 15 minutes.",
+        )
+
+    # Look up user by email
+    result = await session.execute(select(User).where(User.email == str(body.email)))
+    user: Optional[User] = result.scalar_one_or_none()
+
+    # IP extraction for audit log (used in both success and failure paths)
+    _ip = get_client_ip(request)
+
+    # Verify password (anti-enumeration: same error regardless of whether user exists)
+    if user is None or not auth_service.verify_password(body.password, user.password_hash):
+        await write_audit_log(
+            session,
+            event_type="auth.login_failed",
+            user_id=user.id if user else None,
+            actor_id=user.id if user else None,
+            resource_id=None,
+            ip_address=_ip,
+            metadata_={"attempted_email_hash": hashlib.sha256(str(body.email).encode()).hexdigest()[:16]},
+        )
+        await session.commit()
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect email or password",
+        )
+
+    # Active check
+    if not user.is_active:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Account deactivated",
+        )
+
+    # Password must change: return challenge without issuing tokens (T-02-16)
+    if user.password_must_change:
+        return {"requires_password_change": True, "user_id": str(user.id)}
+
+    # TOTP second-factor dispatch
+    if user.totp_enabled:
+        if body.totp_code is None and body.backup_code is None:
+            # Challenge: prompt for second factor
+            return {"requires_totp": True}
+
+        if body.totp_code is not None:
+            # TOTP path takes precedence (even if backup_code also provided)
+            ok = await auth_service.verify_totp(session, user.id, body.totp_code, redis_client)
+            if not ok:
+                raise HTTPException(
+                    status_code=status.HTTP_401_UNAUTHORIZED,
+                    detail="Incorrect code",
+                )
+        else:
+            # Backup code path (body.backup_code is not None and body.totp_code is None)
+            ok = await auth_service.verify_backup_code(session, user.id, body.backup_code)
+            if not ok:
+                raise HTTPException(
+                    status_code=status.HTTP_401_UNAUTHORIZED,
+                    detail="Invalid or already used code",
+                )
+            # D-13: backup code used event
+            await write_audit_log(
+                session,
+                event_type="auth.backup_code_used",
+                user_id=user.id,
+                actor_id=user.id,
+                resource_id=None,
+                ip_address=_ip,
+            )
+
+    # Issue tokens
+    access_token = auth_service.create_access_token(
+        str(user.id),
+        user.role,
+        user_agent=request.headers.get("User-Agent", ""),
+        accept_lang=request.headers.get("Accept-Language", ""),
+    )
+    raw_refresh = await auth_service.create_refresh_token(session, user.id, remember_me=body.remember_me)
+    _set_refresh_cookie(response, raw_refresh, remember_me=body.remember_me)
+
+    # D-13: login success event
+    await write_audit_log(
+        session,
+        event_type="auth.login",
+        user_id=user.id,
+        actor_id=user.id,
+        resource_id=None,
+        ip_address=_ip,
+        metadata_={"totp_used": user.totp_enabled and body.totp_code is not None},
+    )
+    await session.commit()
+
+    return {
+        "access_token": access_token,
+        "user": {
+            "id": str(user.id),
+            "handle": user.handle,
+            "email": user.email,
+            "role": user.role,
+            "totp_enabled": user.totp_enabled,
+        },
+    }
+
+
+# ── POST /refresh ─────────────────────────────────────────────────────────────
+
+@router.post("/refresh")
+@limiter.limit("10/minute")
+async def refresh_token(
+    request: Request,
+    response: Response,
+    session: AsyncSession = Depends(get_db),
+):
+    """Rotate the refresh token.
+
+    Reads the refresh_token httpOnly cookie; on success issues a new access
+    token and rotates the refresh cookie.
+    On token reuse (revoked token presented), revokes entire family and raises 401.
+    """
+    raw_token = request.cookies.get("refresh_token")
+    if not raw_token:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="No refresh token",
+        )
+
+    try:
+        new_raw, user_id_str = await auth_service.rotate_refresh_token(session, raw_token)
+    except ValueError as exc:
+        if "token_family_revoked" in str(exc):
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail="Session revoked",
+            ) from exc
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired refresh token",
+        ) from exc
+
+    # Look up user for response body
+    user = await session.get(User, uuid.UUID(user_id_str))
+    if user is None or not user.is_active:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="User not found or deactivated",
+        )
+
+    # Set new refresh cookie
+    _set_refresh_cookie(response, new_raw)
+
+    access_token = auth_service.create_access_token(
+        user_id_str,
+        user.role,
+        user_agent=request.headers.get("User-Agent", ""),
+        accept_lang=request.headers.get("Accept-Language", ""),
+    )
+    return {
+        "access_token": access_token,
+        "user": {
+            "id": str(user.id),
+            "handle": user.handle,
+            "email": user.email,
+            "role": user.role,
+            "totp_enabled": user.totp_enabled,
+        },
+    }
+
+
+# ── POST /logout ──────────────────────────────────────────────────────────────
+
+@router.post("/logout")
+async def logout(request: Request, response: Response, session: AsyncSession = Depends(get_db)):
+    """Revoke current refresh token and clear the cookie."""
+    import hashlib as _hashlib
+
+    _ip = get_client_ip(request)
+
+    raw_token = request.cookies.get("refresh_token")
+    _logout_user_id = None
+    if raw_token:
+        token_hash = _hashlib.sha256(raw_token.encode()).hexdigest()
+        result = await session.execute(
+            select(RefreshToken).where(RefreshToken.token_hash == token_hash)
+        )
+        row: Optional[RefreshToken] = result.scalar_one_or_none()
+        if row is not None:
+            _logout_user_id = row.user_id
+            row.revoked = True
+            # D-13: logout event (written before commit, within same transaction)
+            await write_audit_log(
+                session,
+                event_type="auth.logout",
+                user_id=_logout_user_id,
+                actor_id=_logout_user_id,
+                resource_id=None,
+                ip_address=_ip,
+            )
+            await session.commit()
+
+    response.delete_cookie("refresh_token", path="/api/auth/refresh")
+    return {"message": "Logged out"}
+
+
+# ── POST /logout-all ──────────────────────────────────────────────────────────
+
+@router.post("/logout-all")
+async def logout_all(
+    request: Request,
+    response: Response,
+    session: AsyncSession = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """Sign out of all devices: revoke all refresh tokens for current user."""
+    _ip = get_client_ip(request)
+    count = await auth_service.revoke_all_refresh_tokens(session, current_user.id)
+    # D-13: sign-out-all event
+    await write_audit_log(
+        session,
+        event_type="auth.sign_out_all",
+        user_id=current_user.id,
+        actor_id=current_user.id,
+        resource_id=None,
+        ip_address=_ip,
+        metadata_={"sessions_revoked": count},
+    )
+    await session.commit()
+    response.delete_cookie("refresh_token", path="/api/auth/refresh")
+    return {"message": f"Signed out of {count} session(s)"}
+
+
+# ── GET /me ───────────────────────────────────────────────────────────────────
+
+@router.get("/me")
+async def get_me(current_user: User = Depends(get_current_user)):
+    """Return the current user's profile (requires valid Bearer token)."""
+    return _user_dict(current_user)
+
+
+# ── GET /me/quota ─────────────────────────────────────────────────────────────
+
+@router.get("/me/quota")
+async def get_my_quota(
+    current_user: User = Depends(get_current_user),
+    session: AsyncSession = Depends(get_db),
+):
+    """Return the current user's quota usage (STORE-04).
+
+    Returns {"used_bytes": int, "limit_bytes": int} for the sidebar quota bar.
+    Quota row is created at registration (100 MB default — STORE-01).
+    """
+    q = await session.get(Quota, current_user.id)
+    if q is None:
+        raise HTTPException(status_code=404, detail="Quota not found")
+    return {"used_bytes": q.used_bytes, "limit_bytes": q.limit_bytes}
+
+
+# ── GET /me/preferences ───────────────────────────────────────────────────────
+
+@router.get("/me/preferences")
+async def get_my_preferences(
+    current_user: User = Depends(get_current_user),
+):
+    """Return the current user's PDF open mode preference (D-10).
+
+    Both regular users and admins can read their own preferences.
+    Falls back to 'in_app' if the column is absent (migration not yet run).
+    """
+    try:
+        pdf_open_mode = current_user.pdf_open_mode
+    except AttributeError:
+        pdf_open_mode = "in_app"
+    return {"pdf_open_mode": pdf_open_mode}
+
+
+# ── PATCH /me/preferences ─────────────────────────────────────────────────────
+
+@router.patch("/me/preferences")
+async def update_my_preferences(
+    body: PreferencesUpdate,
+    session: AsyncSession = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """Update the current user's PDF open mode preference (D-10).
+
+    Both regular users and admins can update their own preferences.
+    Pydantic Literal["in_app", "new_tab"] enforces strict allowlist (T-04-05-05).
+    """
+    user = await session.get(User, current_user.id)
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    user.pdf_open_mode = body.pdf_open_mode
+    session.add(user)
+    await session.commit()
+    return {"pdf_open_mode": user.pdf_open_mode}