diff --git a/aiohttp_json_rpc/auth/__init__.py b/aiohttp_json_rpc/auth/__init__.py
index 3656854..c6f97ce 100644
--- a/aiohttp_json_rpc/auth/__init__.py
+++ b/aiohttp_json_rpc/auth/__init__.py
@@ -3,7 +3,7 @@ class AuthBackend:
 
 
 class DummyAuthBackend(AuthBackend):
-    def prepare_request(self, request):
+    async def prepare_request(self, request):
         request.methods = request.rpc.methods
         request.topics = set(request.rpc.topics.keys())
         request.subscriptions = set()
diff --git a/aiohttp_json_rpc/auth/django.py b/aiohttp_json_rpc/auth/django.py
index 6fa6c4d..4819875 100644
--- a/aiohttp_json_rpc/auth/django.py
+++ b/aiohttp_json_rpc/auth/django.py
@@ -175,12 +175,12 @@ async def login(self, request):
         )
 
         # rediscover methods and topics
-        self.prepare_request(request.http_request, user=user)
+        await self.prepare_request(request.http_request, user=user)
 
         return True
 
     # request processing
-    def prepare_request(self, request, user=None):
+    async def prepare_request(self, request, user=None):
         request.user = user or self.get_user(request)
         request.methods = {}
 
diff --git a/aiohttp_json_rpc/auth/passwd.py b/aiohttp_json_rpc/auth/passwd.py
index 07f54b6..b8e14c2 100644
--- a/aiohttp_json_rpc/auth/passwd.py
+++ b/aiohttp_json_rpc/auth/passwd.py
@@ -126,7 +126,7 @@ def _is_authorized(self, request, method):
 
         return True
 
-    def prepare_request(self, request):
+    async def prepare_request(self, request):
         if not hasattr(request, 'user'):
             request.user = None
 
@@ -175,7 +175,7 @@ async def login(self, request):
             await loop.run_in_executor(None, self._login, username, password))
 
         # rediscover methods
-        self.prepare_request(request.http_request)
+        await self.prepare_request(request.http_request)
 
         return bool(request.http_request.user)
 
@@ -184,7 +184,7 @@ async def logout(self, request):
         request.http_request.user = None
         request.http_request.permissions = set()
 
-        self.prepare_request(request.http_request)
+        await self.prepare_request(request.http_request)
 
         return True
 
diff --git a/aiohttp_json_rpc/rpc.py b/aiohttp_json_rpc/rpc.py
index 030f044..5a5e2f3 100644
--- a/aiohttp_json_rpc/rpc.py
+++ b/aiohttp_json_rpc/rpc.py
@@ -253,7 +253,7 @@ def __call__(self, request):
     async def handle_request(self, request):
         # prepare request
         request.rpc = self
-        self.auth_backend.prepare_request(request)
+        await self.auth_backend.prepare_request(request)
 
         # handle request
         if request.method == 'GET':