Webserver: Sanitize values passed to origin param (#10334)

airflow/www/views.py

@@ -27,7 +27,7 @@
 from datetime import datetime, timedelta
 from json import JSONDecodeError
 from typing import Dict, List, Optional, Tuple
-from urllib.parse import unquote
+from urllib.parse import unquote, urlparse
 
 import lazy_object_proxy
 import nvd3
@@ -81,6 +81,19 @@
 FILTER_STATUS_COOKIE = 'dag_status_filter'
 
 
+def get_safe_url(url):
+    """Given a user-supplied URL, ensure it points to our web server"""
+    valid_schemes = ['http', 'https', '']
+    valid_netlocs = [request.host, '']
+
+    parsed = urlparse(url)
+
+    if parsed.scheme in valid_schemes and parsed.netloc in valid_netlocs:
+        return url
+
+    return url_for('Airflow.index')
+
+
 def get_date_time_num_runs_dag_runs_form_data(request, session, dag):
     """Get Execution Data, Base Date & Number of runs from a Request """
     dttm = request.args.get('execution_date')
@@ -921,7 +934,7 @@ def xcom(self, session=None):
     def run(self):
         dag_id = request.form.get('dag_id')
         task_id = request.form.get('task_id')
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         dag = current_app.dag_bag.get_dag(dag_id)
         task = dag.get_task(task_id)
 
@@ -990,7 +1003,7 @@ def delete(self):
         from airflow.exceptions import DagFileExists, DagNotFound
 
         dag_id = request.values.get('dag_id')
-        origin = request.values.get('origin') or url_for('Airflow.index')
+        origin = get_safe_url(request.values.get('origin'))
 
         try:
             delete_dag.delete_dag(dag_id)
@@ -1017,7 +1030,7 @@ def delete(self):
     def trigger(self, session=None):
 
         dag_id = request.values.get('dag_id')
-        origin = request.values.get('origin') or url_for('Airflow.index')
+        origin = get_safe_url(request.values.get('origin'))
 
         if request.method == 'GET':
             return self.render_template(
@@ -1115,7 +1128,7 @@ def _clear_dag_tis(self, dag, start_date, end_date, origin,
     def clear(self):
         dag_id = request.form.get('dag_id')
         task_id = request.form.get('task_id')
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         dag = current_app.dag_bag.get_dag(dag_id)
 
         execution_date = request.form.get('execution_date')
@@ -1145,7 +1158,7 @@ def clear(self):
     @action_logging
     def dagrun_clear(self):
         dag_id = request.form.get('dag_id')
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         execution_date = request.form.get('execution_date')
         confirmed = request.form.get('confirmed') == "true"
 
@@ -1267,7 +1280,7 @@ def dagrun_failed(self):
         dag_id = request.form.get('dag_id')
         execution_date = request.form.get('execution_date')
         confirmed = request.form.get('confirmed') == 'true'
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         return self._mark_dagrun_state_as_failed(dag_id, execution_date,
                                                  confirmed, origin)
 
@@ -1279,7 +1292,7 @@ def dagrun_success(self):
         dag_id = request.form.get('dag_id')
         execution_date = request.form.get('execution_date')
         confirmed = request.form.get('confirmed') == 'true'
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         return self._mark_dagrun_state_as_success(dag_id, execution_date,
                                                   confirmed, origin)
 
@@ -1329,7 +1342,7 @@ def _mark_task_instance_state(self, dag_id, task_id, origin, execution_date,
     def failed(self):
         dag_id = request.form.get('dag_id')
         task_id = request.form.get('task_id')
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         execution_date = request.form.get('execution_date')
 
         confirmed = request.form.get('confirmed') == "true"
@@ -1349,7 +1362,7 @@ def failed(self):
     def success(self):
         dag_id = request.form.get('dag_id')
         task_id = request.form.get('task_id')
-        origin = request.form.get('origin')
+        origin = get_safe_url(request.form.get('origin'))
         execution_date = request.form.get('execution_date')
 
         confirmed = request.form.get('confirmed') == "true"

tests/www/test_views.py

@@ -2468,6 +2468,21 @@ def test_trigger_dag_form(self):
         self.assertEqual(resp.status_code, 200)
         self.check_content_in_response('Trigger DAG: {}'.format(test_dag_id), resp)
 
+    @parameterized.expand([
+        ("javascript:alert(1)", "/home"),
+        ("http://google.com", "/home"),
+        ("%2Ftree%3Fdag_id%3Dexample_bash_operator", "/tree?dag_id=example_bash_operator"),
+        ("%2Fgraph%3Fdag_id%3Dexample_bash_operator", "/graph?dag_id=example_bash_operator"),
+    ])
+    def test_trigger_dag_form_origin_url(self, test_origin, expected_origin):
+        test_dag_id = "example_bash_operator"
+
+        resp = self.client.get('trigger?dag_id={}&origin={}'.format(test_dag_id, test_origin))
+        self.check_content_in_response(
+            '<button class="btn" onclick="location.href = \'{}\'; return false">'.format(
+                expected_origin),
+            resp)
+
     def test_trigger_endpoint_uses_existing_dagbag(self):
         """
         Test that Trigger Endpoint uses the DagBag already created in views.py