From 58e23657884454f6f6b5fac387a84bb7250fb140 Mon Sep 17 00:00:00 2001
From: Mike Auty <mike@ikelos.org>
Date: Tue, 8 Jul 2014 11:17:39 +0100
Subject: [PATCH] Add in initial requirements for plugins to state their
 inputs.

---
 volatility/framework/interfaces/plugins.py | 22 +++++++++++++++++++++-
 volatility/plugins/windows/pslist.py       |  6 +++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/volatility/framework/interfaces/plugins.py b/volatility/framework/interfaces/plugins.py
index 7e421d1ed..a618c4c20 100644
--- a/volatility/framework/interfaces/plugins.py
+++ b/volatility/framework/interfaces/plugins.py
@@ -30,11 +30,31 @@ class PluginInterface(validity.ValidityRoutines):
     def context(self):
         return self._context
 
+    @abstractmethod
+    @classmethod
+    def determine_inputs(cls):
+        """Returns the accepted inputs
+
+           This should be a dictionary of TranslationLayer names matched to TranslationLayer types
+        """
+
+    def verify_inputs(self):
+        """Verifies the inputs basedo on the output of determine_inputs"""
+        inputs = self.determine_inputs()
+        for tl_name, tl_type in inputs.items():
+            layer = self.context.memory.get(tl_name, None)
+            if layer is not None:
+                if layer.__class__.__name__ != tl_type:
+                    raise TypeError("Layer " + tl_name + " is not of type " + tl_type + " (" +
+                                    layer.__class__.__name__ + " instead).")
+            else:
+                raise TypeError("Layer " + tl_name + " has not been populated.")
+
     @abstractmethod
     def establish_context(self):
         """Alters the context to ensure the plugin can run.
 
-        This function constructs the necessary address spaces and symbol spaces that the plugin will need.
+        This function constructs the necessary symbol spaces that the plugin will need.
         """
 
     @abstractmethod
diff --git a/volatility/plugins/windows/pslist.py b/volatility/plugins/windows/pslist.py
index 0f68cace3..193a77940 100644
--- a/volatility/plugins/windows/pslist.py
+++ b/volatility/plugins/windows/pslist.py
@@ -2,4 +2,8 @@
 import volatility.framework.interfaces.plugins as plugins
 
 class pslist(plugins.PluginInterface):
-    pass
+
+    @classmethod
+    def determine_inputs(cls):
+        return {"primary":"Intel"}
+