feat(oauth): plugin oauth service (#21480)

api/services/plugin/oauth_service.py

@@ -1,7 +1,61 @@
+import json
+import uuid
+
 from core.plugin.impl.base import BasePluginClient
+from extensions.ext_redis import redis_client
 
 
-class OAuthService(BasePluginClient):
-    @classmethod
-    def get_authorization_url(cls, tenant_id: str, user_id: str, provider_name: str) -> str:
-        return "1234567890"
+class OAuthProxyService(BasePluginClient):
+    # Default max age for proxy context parameter in seconds
+    __MAX_AGE__ = 5 * 60  # 5 minutes
+
+    @staticmethod
+    def create_proxy_context(user_id, tenant_id, plugin_id, provider):
+        """
+        Create a proxy context for an OAuth 2.0 authorization request.
+
+        This parameter is a crucial security measure to prevent Cross-Site Request
+        Forgery (CSRF) attacks. It works by generating a unique nonce and storing it
+        in a distributed cache (Redis) along with the user's session context.
+
+        The returned nonce should be included as the 'proxy_context' parameter in the
+        authorization URL. Upon callback, the `use_proxy_context` method
+        is used to verify the state, ensuring the request's integrity and authenticity,
+        and mitigating replay attacks.
+        """
+        seconds, _ = redis_client.time()
+        context_id = str(uuid.uuid4())
+        data = {
+            "user_id": user_id,
+            "plugin_id": plugin_id,
+            "tenant_id": tenant_id,
+            "provider": provider,
+            # encode redis time to avoid distribution time skew
+            "timestamp": seconds,
+        }
+        # ignore nonce collision
+        redis_client.setex(
+            f"oauth_proxy_context:{context_id}",
+            OAuthProxyService.__MAX_AGE__,
+            json.dumps(data),
+        )
+        return context_id
+
+    @staticmethod
+    def use_proxy_context(context_id, max_age=__MAX_AGE__):
+        """
+        Validate the proxy context parameter.
+        This checks if the context_id is valid and not expired.
+        """
+        if not context_id:
+            raise ValueError("context_id is required")
+        # get data from redis
+        data = redis_client.getdel(f"oauth_proxy_context:{context_id}")
+        if not data:
+            raise ValueError("context_id is invalid")
+        # check if data is expired
+        seconds, _ = redis_client.time()
+        state = json.loads(data)
+        if state.get("timestamp") < seconds - max_age:
+            raise ValueError("context_id is expired")
+        return state