perf(users): 优化用户认证来源

apps/authentication/mixins.py

@@ -1,13 +1,17 @@
 # -*- coding: utf-8 -*-
 #
+import inspect
 from urllib.parse import urlencode
 from functools import partial
 import time
 
 from django.conf import settings
-from django.contrib.auth import authenticate
+from django.contrib import auth
+from django.contrib.auth import (
+    BACKEND_SESSION_KEY, _get_backends,
+    PermissionDenied, user_login_failed, _clean_credentials
+)
 from django.shortcuts import reverse
-from django.contrib.auth import BACKEND_SESSION_KEY
 
 from common.utils import get_object_or_none, get_request_ip, get_logger, bulk_get
 from users.models import User
@@ -22,6 +26,59 @@ from .const import RSA_PRIVATE_KEY
 logger = get_logger(__name__)
 
 
+def check_backend_can_auth(username, backend_path, allowed_auth_backends):
+    if allowed_auth_backends is not None and backend_path not in allowed_auth_backends:
+        logger.debug('Skip user auth backend: {}, {} not in'.format(
+                username, backend_path, ','.join(allowed_auth_backends)
+            )
+        )
+        return False
+    return True
+
+
+def authenticate(request=None, **credentials):
+    """
+    If the given credentials are valid, return a User object.
+    """
+    username = credentials.get('username')
+    allowed_auth_backends = User.get_user_allowed_auth_backends(username)
+
+    for backend, backend_path in _get_backends(return_tuples=True):
+        # 预先检查，不浪费认证时间
+        if not check_backend_can_auth(username, backend_path, allowed_auth_backends):
+            continue
+
+        backend_signature = inspect.signature(backend.authenticate)
+        try:
+            backend_signature.bind(request, **credentials)
+        except TypeError:
+            # This backend doesn't accept these credentials as arguments. Try the next one.
+            continue
+        try:
+            user = backend.authenticate(request, **credentials)
+        except PermissionDenied:
+            # This backend says to stop in our tracks - this user should not be allowed in at all.
+            break
+        if user is None:
+            continue
+        # 如果是 None, 证明没有检查过, 需要再次检查
+        if allowed_auth_backends is None:
+            # 有些 authentication 参数中不带 username, 之后还要再检查
+            allowed_auth_backends = user.get_allowed_auth_backends()
+            if not check_backend_can_auth(user.username, backend_path, allowed_auth_backends):
+                continue
+
+        # Annotate the user object with the path of the backend.
+        user.backend = backend_path
+        return user
+
+    # The credentials supplied are invalid to all backends, fire signal
+    user_login_failed.send(sender=__name__, credentials=_clean_credentials(credentials), request=request)
+
+
+auth.authenticate = authenticate
+
+
 class AuthMixin:
     request = None
     partial_credential_error = None
@@ -121,13 +178,6 @@ class AuthMixin:
             self.raise_credential_error(errors.reason_user_inactive)
         return user
 
-    def _check_auth_source_is_valid(self, user, auth_backend):
-        # 限制只能从认证来源登录
-        if settings.ONLY_ALLOW_AUTH_FROM_SOURCE:
-            auth_backends_allowed = user.SOURCE_BACKEND_MAPPING.get(user.source)
-            if auth_backend not in auth_backends_allowed:
-                self.raise_credential_error(error=errors.reason_backend_not_match)
-
     def _check_login_acl(self, user, ip):
         # ACL 限制用户登录
         from acls.models import LoginACL
@@ -144,9 +194,6 @@ class AuthMixin:
         user = self._check_auth_user_is_valid(username, password, public_key)
         # 校验login-acl规则
         self._check_login_acl(user, ip)
-        # 限制只能从认证来源登录
-        auth_backend = getattr(user, 'backend', 'django.contrib.auth.backends.ModelBackend')
-        self._check_auth_source_is_valid(user, auth_backend)
         self._check_password_require_reset_or_not(user)
         self._check_passwd_is_too_simple(user, password)
 
@@ -154,7 +201,7 @@ class AuthMixin:
         request.session['auth_password'] = 1
         request.session['user_id'] = str(user.id)
         request.session['auto_login'] = auto_login
-        request.session['auth_backend'] = auth_backend
+        request.session['auth_backend'] = getattr(user, 'backend', settings.AUTH_BACKEND_MODEL)
         return user
 
     @classmethod

apps/users/models/user.py

@@ -679,6 +679,21 @@ class User(AuthMixin, TokenMixin, RoleMixin, MFAMixin, AbstractUser):
             return
         return super(User, self).delete()
 
+    @classmethod
+    def get_user_allowed_auth_backends(cls, username):
+        if not settings.ONLY_ALLOW_AUTH_FROM_SOURCE or not username:
+            # return settings.AUTHENTICATION_BACKENDS
+            return None
+        user = cls.objects.filter(username=username).first()
+        if not user:
+            return None
+        return user.get_allowed_auth_backends()
+
+    def get_allowed_auth_backends(self):
+        if not settings.ONLY_ALLOW_AUTH_FROM_SOURCE:
+            return None
+        return self.SOURCE_BACKEND_MAPPING.get(self.source, [])
+
     class Meta:
         ordering = ['username']
         verbose_name = _("User")