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mirror of https://github.com/etesync/server synced 2024-12-29 10:48:07 +00:00
etesync-server/etebase_fastapi/authentication.py
2020-12-28 16:42:39 +02:00

314 lines
11 KiB
Python

import dataclasses
import typing as t
from datetime import datetime
from functools import cached_property
import nacl
import nacl.encoding
import nacl.hash
import nacl.secret
import nacl.signing
from asgiref.sync import sync_to_async
from django.conf import settings
from django.contrib.auth import get_user_model, user_logged_out, user_logged_in
from django.core import exceptions as django_exceptions
from django.db import transaction
from django.utils import timezone
from fastapi import APIRouter, Depends, status, Request
from fastapi.security import APIKeyHeader
from django_etebase import app_settings, models
from django_etebase.models import UserInfo
from django_etebase.signals import user_signed_up
from django_etebase.token_auth.models import AuthToken
from django_etebase.token_auth.models import get_default_expiry
from django_etebase.utils import create_user, get_user_queryset, CallbackContext
from .exceptions import AuthenticationFailed, transform_validation_error, HttpError
from .msgpack import MsgpackRoute
from .utils import BaseModel, permission_responses, msgpack_encode, msgpack_decode
User = get_user_model()
token_scheme = APIKeyHeader(name="Authorization")
AUTO_REFRESH = True
MIN_REFRESH_INTERVAL = 60
authentication_router = APIRouter(route_class=MsgpackRoute)
@dataclasses.dataclass(frozen=True)
class AuthData:
user: User
token: AuthToken
class LoginChallengeIn(BaseModel):
username: str
class LoginChallengeOut(BaseModel):
salt: bytes
challenge: bytes
version: int
class LoginResponse(BaseModel):
username: str
challenge: bytes
host: str
action: t.Literal["login", "changePassword"]
class UserOut(BaseModel):
pubkey: bytes
encryptedContent: bytes
@classmethod
def from_orm(cls: t.Type["UserOut"], obj: User) -> "UserOut":
return cls(pubkey=obj.userinfo.pubkey, encryptedContent=obj.userinfo.encryptedContent)
class LoginOut(BaseModel):
token: str
user: UserOut
@classmethod
def from_orm(cls: t.Type["LoginOut"], obj: User) -> "LoginOut":
token = AuthToken.objects.create(user=obj).key
user = UserOut.from_orm(obj)
return cls(token=token, user=user)
class Authentication(BaseModel):
class Config:
keep_untouched = (cached_property,)
response: bytes
signature: bytes
class Login(Authentication):
@cached_property
def response_data(self) -> LoginResponse:
return LoginResponse(**msgpack_decode(self.response))
class ChangePasswordResponse(LoginResponse):
loginPubkey: bytes
encryptedContent: bytes
class ChangePassword(Authentication):
@cached_property
def response_data(self) -> ChangePasswordResponse:
return ChangePasswordResponse(**msgpack_decode(self.response))
class UserSignup(BaseModel):
username: str
email: str
class SignupIn(BaseModel):
user: UserSignup
salt: bytes
loginPubkey: bytes
pubkey: bytes
encryptedContent: bytes
def __renew_token(auth_token: AuthToken):
current_expiry = auth_token.expiry
new_expiry = get_default_expiry()
# Throttle refreshing of token to avoid db writes
delta = (new_expiry - current_expiry).total_seconds()
if delta > MIN_REFRESH_INTERVAL:
auth_token.expiry = new_expiry
auth_token.save(update_fields=("expiry",))
@sync_to_async
def __get_authenticated_user(api_token: str):
api_token = api_token.split()[1]
try:
token: AuthToken = AuthToken.objects.select_related("user").get(key=api_token)
except AuthToken.DoesNotExist:
raise AuthenticationFailed(detail="Invalid token.")
if not token.user.is_active:
raise AuthenticationFailed(detail="User inactive or deleted.")
if token.expiry is not None:
if token.expiry < timezone.now():
token.delete()
raise AuthenticationFailed(detail="Invalid token.")
if AUTO_REFRESH:
__renew_token(token)
return token.user, token
async def get_auth_data(api_token: str = Depends(token_scheme)) -> AuthData:
user, token = await __get_authenticated_user(api_token)
return AuthData(user, token)
async def get_authenticated_user(api_token: str = Depends(token_scheme)) -> User:
user, token = await __get_authenticated_user(api_token)
return user
@sync_to_async
def __get_login_user(username: str) -> User:
kwargs = {User.USERNAME_FIELD + "__iexact": username.lower()}
try:
user = User.objects.get(**kwargs)
if not hasattr(user, "userinfo"):
raise AuthenticationFailed(code="user_not_init", detail="User not properly init")
return user
except User.DoesNotExist:
raise AuthenticationFailed(code="user_not_found", detail="User not found")
async def get_login_user(challenge: LoginChallengeIn) -> User:
user = await __get_login_user(challenge.username)
return user
def get_encryption_key(salt):
key = nacl.hash.blake2b(settings.SECRET_KEY.encode(), encoder=nacl.encoding.RawEncoder)
return nacl.hash.blake2b(
b"",
key=key,
salt=salt[: nacl.hash.BLAKE2B_SALTBYTES],
person=b"etebase-auth",
encoder=nacl.encoding.RawEncoder,
)
def save_changed_password(data: ChangePassword, user: User):
response_data = data.response_data
user_info: UserInfo = user.userinfo
user_info.loginPubkey = response_data.loginPubkey
user_info.encryptedContent = response_data.encryptedContent
user_info.save()
@sync_to_async
def validate_login_request(
validated_data: LoginResponse,
challenge_sent_to_user: Authentication,
user: User,
expected_action: str,
host_from_request: str,
):
enc_key = get_encryption_key(bytes(user.userinfo.salt))
box = nacl.secret.SecretBox(enc_key)
challenge_data = msgpack_decode(box.decrypt(validated_data.challenge))
now = int(datetime.now().timestamp())
if validated_data.action != expected_action:
raise HttpError("wrong_action", f'Expected "{challenge_sent_to_user.response}" but got something else')
elif now - challenge_data["timestamp"] > app_settings.CHALLENGE_VALID_SECONDS:
raise HttpError("challenge_expired", "Login challenge has expired")
elif challenge_data["userId"] != user.id:
raise HttpError("wrong_user", "This challenge is for the wrong user")
elif not settings.DEBUG and validated_data.host.split(":", 1)[0] != host_from_request:
raise HttpError(
"wrong_host", f'Found wrong host name. Got: "{validated_data.host}" expected: "{host_from_request}"'
)
verify_key = nacl.signing.VerifyKey(bytes(user.userinfo.loginPubkey), encoder=nacl.encoding.RawEncoder)
try:
verify_key.verify(challenge_sent_to_user.response, challenge_sent_to_user.signature)
except nacl.exceptions.BadSignatureError:
raise HttpError("login_bad_signature", "Wrong password for user.", status.HTTP_401_UNAUTHORIZED)
@authentication_router.get("/is_etebase/")
async def is_etebase():
pass
@authentication_router.post("/login_challenge/", response_model=LoginChallengeOut)
async def login_challenge(user: User = Depends(get_login_user)):
enc_key = get_encryption_key(user.userinfo.salt)
box = nacl.secret.SecretBox(enc_key)
challenge_data = {
"timestamp": int(datetime.now().timestamp()),
"userId": user.id,
}
challenge = bytes(box.encrypt(msgpack_encode(challenge_data), encoder=nacl.encoding.RawEncoder))
return LoginChallengeOut(salt=user.userinfo.salt, challenge=challenge, version=user.userinfo.version)
@authentication_router.post("/login/", response_model=LoginOut)
async def login(data: Login, request: Request):
user = await get_login_user(LoginChallengeIn(username=data.response_data.username))
host = request.headers.get("Host")
await validate_login_request(data.response_data, data, user, "login", host)
data = await sync_to_async(LoginOut.from_orm)(user)
await sync_to_async(user_logged_in.send)(sender=user.__class__, request=None, user=user)
return data
@authentication_router.post("/logout/", status_code=status.HTTP_204_NO_CONTENT, responses=permission_responses)
async def logout(request: Request, auth_data: AuthData = Depends(get_auth_data)):
await sync_to_async(auth_data.token.delete)()
# XXX-TOM
await sync_to_async(user_logged_out.send)(sender=auth_data.user.__class__, request=None, user=auth_data.user)
@authentication_router.post("/change_password/", status_code=status.HTTP_204_NO_CONTENT, responses=permission_responses)
async def change_password(data: ChangePassword, request: Request, user: User = Depends(get_authenticated_user)):
host = request.headers.get("Host")
await validate_login_request(data.response_data, data, user, "changePassword", host)
await sync_to_async(save_changed_password)(data, user)
@authentication_router.post("/dashboard_url/", responses=permission_responses)
def dashboard_url(user: User = Depends(get_authenticated_user)):
get_dashboard_url = app_settings.DASHBOARD_URL_FUNC
if get_dashboard_url is None:
raise HttpError("not_supported", "This server doesn't have a user dashboard.")
ret = {
"url": get_dashboard_url(CallbackContext(request.path_params, user=user)),
}
return ret
def signup_save(data: SignupIn, request: Request) -> User:
user_data = data.user
with transaction.atomic():
try:
user_queryset = get_user_queryset(User.objects.all(), CallbackContext(request.path_params))
instance = user_queryset.get(**{User.USERNAME_FIELD: user_data.username.lower()})
except User.DoesNotExist:
# Create the user and save the casing the user chose as the first name
try:
instance = create_user(
**user_data.dict(),
password=None,
first_name=user_data.username,
context=CallbackContext(request.path_params),
)
instance.full_clean()
except HttpError as e:
raise e
except django_exceptions.ValidationError as e:
transform_validation_error("user", e)
except Exception as e:
raise HttpError("generic", str(e))
if hasattr(instance, "userinfo"):
raise HttpError("user_exists", "User already exists", status_code=status.HTTP_409_CONFLICT)
models.UserInfo.objects.create(**data.dict(exclude={"user"}), owner=instance)
return instance
@authentication_router.post("/signup/", response_model=LoginOut, status_code=status.HTTP_201_CREATED)
async def signup(data: SignupIn, request: Request):
user = await sync_to_async(signup_save)(data, request)
# XXX-TOM
data = await sync_to_async(LoginOut.from_orm)(user)
await sync_to_async(user_signed_up.send)(sender=user.__class__, request=None, user=user)
return data