diff --git a/test/infamy/env.py b/test/infamy/env.py
index e38c8127..be54ef60 100644
--- a/test/infamy/env.py
+++ b/test/infamy/env.py
@@ -7,6 +7,12 @@ import sys
 
 from . import neigh, netconf, tap, topology
 
+class NullEnv:
+    def attr(self, _, default=None):
+        return default
+
+ENV = NullEnv()
+
 class ArgumentParser(argparse.ArgumentParser):
     def __init__(self, ltop):
         super().__init__()
@@ -37,6 +43,21 @@ class Env(object):
 
             print(repr(self.ltop))
 
+        global ENV
+        ENV = self
+
+    def attr(self, name, default=None):
+        val = self.ptop.get_attr("ix_" + name)
+        if val == None:
+            return default
+
+        try:
+            return int(val, 0)
+        except ValueError:
+            pass
+
+        return val
+
     def attach(self, node, port, factory_default=True):
         if self.ltop:
             mapping = self.ltop.mapping[node]