Make received MIB objects resolution more forgiving

Previously, MIB resolution errors were ignored (whenever possible)
for objects we were sending and receiving. This change tightens
outgoing objects MIB compliance (send will fail), but tolerate
non quite compliant objects we receive.

Also, extend the same policy onto `NotificationOriginator`.

Author: etingof

CHANGES.txt

@@ -16,9 +16,9 @@ Revision 4.4.10, released 2019-07-29
 
 - Rebased MIB importing code onto `importlib` because `imp` is long
   deprecated
-- MIB objects resolution made more forgiving to errors, added optional
-  `ignoreErrors` parameter to `ObjectType.resolveWithMib()` to control
-  that behaviour.
+- Received MIB objects resolution made more forgiving to errors, added
+  optional `ignoreErrors` parameter to `ObjectType.resolveWithMib()` to
+  control that behaviour.
 - Fixed asyncore main loop to respect non-default timer resolution
 - Fixed `.setTimerResolution()` behaviour of abstract main loop dispatcher
   to update call intervals of the existing periodic dispatcher jobs

pysnmp/hlapi/varbinds.py

@@ -36,14 +36,15 @@ def makeVarBinds(self, snmpEngine, varBinds):
             else:
                 varBind = ObjectType(ObjectIdentity(varBind[0]), varBind[1])
 
-            __varBinds.append(varBind.resolveWithMib(mibViewController))
+            __varBinds.append(varBind.resolveWithMib(mibViewController, ignoreErrors=False))
 
         return __varBinds
 
     def unmakeVarBinds(self, snmpEngine, varBinds, lookupMib=True):
         if lookupMib:
             mibViewController = self.getMibViewController(snmpEngine)
-            varBinds = [ObjectType(ObjectIdentity(x[0]), x[1]).resolveWithMib(mibViewController) for x in varBinds]
+            varBinds = [ObjectType(ObjectIdentity(x[0]), x[1]).resolveWithMib(
+                mibViewController) for x in varBinds]
 
         return varBinds
 
@@ -52,7 +53,8 @@ class NotificationOriginatorVarBinds(AbstractVarBinds):
     def makeVarBinds(self, snmpEngine, varBinds):
         mibViewController = self.getMibViewController(snmpEngine)
         if isinstance(varBinds, NotificationType):
-            varBinds.resolveWithMib(mibViewController)
+            varBinds.resolveWithMib(
+                mibViewController, ignoreErrors=False)
         __varBinds = []
         for varBind in varBinds:
             if isinstance(varBind, ObjectType):
@@ -61,11 +63,13 @@ def makeVarBinds(self, snmpEngine, varBinds):
                 varBind = ObjectType(*varBind)
             else:
                 varBind = ObjectType(ObjectIdentity(varBind[0]), varBind[1])
-            __varBinds.append(varBind.resolveWithMib(mibViewController))
+            __varBinds.append(varBind.resolveWithMib(
+                mibViewController, ignoreErrors=False))
         return __varBinds
 
     def unmakeVarBinds(self, snmpEngine, varBinds, lookupMib=False):
         if lookupMib:
             mibViewController = self.getMibViewController(snmpEngine)
-            varBinds = [ObjectType(ObjectIdentity(x[0]), x[1]).resolveWithMib(mibViewController) for x in varBinds]
+            varBinds = [ObjectType(ObjectIdentity(x[0]), x[1]).resolveWithMib(
+                mibViewController) for x in varBinds]
         return varBinds

pysnmp/smi/rfc1902.py

@@ -1113,14 +1113,20 @@ def loadMibs(self, *modNames):
     def isFullyResolved(self):
         return self.__state & self.stClean
 
-    def resolveWithMib(self, mibViewController):
+    def resolveWithMib(self, mibViewController, ignoreErrors=True):
         """Perform MIB variable ID conversion and notification objects expansion.
 
         Parameters
         ----------
         mibViewController : :py:class:`~pysnmp.smi.view.MibViewController`
             class instance representing MIB browsing functionality.
 
+        Other Parameters
+        ----------------
+        ignoreErrors: :py:class:`bool`
+            If `True` (default), ignore MIB object name or value casting
+            failures if possible.
+
         Returns
         -------
         : :py:class:`~pysnmp.smi.rfc1902.NotificationType`
@@ -1158,7 +1164,7 @@ class instance representing MIB browsing functionality.
 
         self.__varBinds.append(
             ObjectType(ObjectIdentity(v2c.apiTrapPDU.snmpTrapOID),
-                       self.__objectIdentity).resolveWithMib(mibViewController)
+                       self.__objectIdentity).resolveWithMib(mibViewController, ignoreErrors)
         )
 
         SmiNotificationType, = mibViewController.mibBuilder.importSymbols('SNMPv2-SMI', 'NotificationType')
@@ -1170,11 +1176,11 @@ class instance representing MIB browsing functionality.
         if isinstance(mibNode, SmiNotificationType):
             for notificationObject in mibNode.getObjects():
                 objectIdentity = ObjectIdentity(*notificationObject + self.__instanceIndex).resolveWithMib(
-                    mibViewController)
+                    mibViewController, ignoreErrors)
                 self.__varBinds.append(
                     ObjectType(objectIdentity,
                                self.__objects.get(notificationObject, rfc1905.unSpecified)).resolveWithMib(
-                        mibViewController)
+                        mibViewController, ignoreErrors)
                 )
                 varBindsLocation[objectIdentity] = len(self.__varBinds) - 1
         else:
@@ -1184,7 +1190,7 @@ class instance representing MIB browsing functionality.
         for varBinds in self.__additionalVarBinds:
             if not isinstance(varBinds, ObjectType):
                 varBinds = ObjectType(ObjectIdentity(varBinds[0]), varBinds[1])
-            varBinds.resolveWithMib(mibViewController)
+            varBinds.resolveWithMib(mibViewController, ignoreErrors)
             if varBinds[0] in varBindsLocation:
                 self.__varBinds[varBindsLocation[varBinds[0]]] = varBinds
             else: