Python: support user defined taint source

python/ql/test/experimental/dataflow/tainttracking/defaultAdditionalTaintStep/test_async.py

@@ -45,7 +45,7 @@ async def test_async_for():
     iter = AsyncIter()
     taint(iter)
     async for tainted in iter:
-        ensure_tainted(tainted) # $ MISSING: tainted
+        ensure_tainted(tainted) # $ tainted
 
 
 

python/ql/test/experimental/meta/InlineTaintTest.qll

@@ -38,6 +38,12 @@ class TestTaintTrackingConfiguration extends TaintTracking::Configuration {
         "TAINTED_STRING", "TAINTED_BYTES", "TAINTED_LIST", "TAINTED_DICT"
       ]
     or
+    // User defined sources
+    exists(CallNode call |
+      call.getFunction().(NameNode).getId() = "taint" and
+      source.(DataFlow::CfgNode).getNode() = call.getAnArg()
+    )
+    or
     source instanceof RemoteFlowSource
   }