NotificationReceiver reports SNMPv1 TRAP community string

CHANGES.txt

@@ -9,6 +9,8 @@ Revision 4.3.10, released 2017-10-XX
   it propagates to the return value. Before this fix
   ObjectIdentity.prettyPrint() may crash when rendering malformed SNMP
   table indices.
+- Fixed NotificationReceiver to include SNMPv1 TRAP Message community
+  string into SNMPv2c/v3 TRAP PDU
 - Fixed multiple bugs in SNMP table indices rendering, especially
   the InetAddressIPv6 type which was severely broken.
 - Fixed crashing Bits.prettyPrint() implementation

examples/v3arch/asyncore/manager/ntfrcv/regexp-community-name.py

@@ -28,7 +28,6 @@ CommunityName's, not explicitly configured to local SNMP Engine.
 from pysnmp.entity import engine, config
 from pysnmp.carrier.asyncore.dgram import udp
 from pysnmp.entity.rfc3413 import ntfrcv
-from pysnmp.proto.api import v2c
 import re
 
 # Create SNMP engine with autogenernated engineID and pre-bound

pysnmp/entity/rfc3413/ntfrcv.py

@@ -21,10 +21,17 @@ class NotificationReceiver(object):
         snmpEngine.msgAndPduDsp.registerContextEngineId(
             null, self.pduTypes, self.processPdu  # '' is a wildcard
         )
+
+        self.__snmpTrapCommunity = ''
         self.__cbFunVer = 0
         self.__cbFun = cbFun
         self.__cbCtx = cbCtx
 
+        def storeSnmpTrapCommunity(snmpEngine, execpoint, variables, cbCtx):
+            self.__snmpTrapCommunity = variables.get('communityName', '')
+
+        snmpEngine.observer.registerObserver(storeSnmpTrapCommunity, 'rfc2576.processIncomingMsg')
+
     def close(self, snmpEngine):
         snmpEngine.msgAndPduDsp.unregisterContextEngineId(
             null, self.pduTypes
@@ -39,7 +46,7 @@ class NotificationReceiver(object):
         # Agent-side API complies with SMIv2
         if messageProcessingModel == 0:
             origPdu = PDU
-            PDU = rfc2576.v1ToV2(PDU)
+            PDU = rfc2576.v1ToV2(PDU, snmpTrapCommunity=self.__snmpTrapCommunity)
         else:
             origPdu = None
 

pysnmp/proto/proxy/rfc2576.py

@@ -97,7 +97,7 @@ __v2ToV1ErrorMap = {
 __zeroInt = v1.Integer(0)
 
 
-def v1ToV2(v1Pdu, origV2Pdu=None):
+def v1ToV2(v1Pdu, origV2Pdu=None, snmpTrapCommunity=''):
     pduType = v1Pdu.tagSet
     v2Pdu = __v1ToV2PduMap[pduType].clone()
 
@@ -119,13 +119,13 @@ def v1ToV2(v1Pdu, origV2Pdu=None):
         else:
             snmpTrapOIDParam = v2c.ObjectIdentifier(__v1ToV2TrapMap[genericTrap])
 
-        # 3.1.4 (XXX snmpTrapCommunity.0 is missing here)
+        # 3.1.4
         v2VarBinds.append((v2c.apiTrapPDU.sysUpTime, sysUpTime))
         v2VarBinds.append((v2c.apiTrapPDU.snmpTrapOID, snmpTrapOIDParam))
         v2VarBinds.append(
             (v2c.apiTrapPDU.snmpTrapAddress, v1.apiTrapPDU.getAgentAddr(v1Pdu))
         )
-        v2VarBinds.append((v2c.apiTrapPDU.snmpTrapCommunity, v2c.OctetString("")))
+        v2VarBinds.append((v2c.apiTrapPDU.snmpTrapCommunity, v2c.OctetString(snmpTrapCommunity)))
         v2VarBinds.append((v2c.apiTrapPDU.snmpTrapEnterprise,
                            v1.apiTrapPDU.getEnterprise(v1Pdu)))