From 2f24177c361ba4d9deba2d7378f84aa96111db80 Mon Sep 17 00:00:00 2001 From: elie Date: Mon, 14 Sep 2015 05:20:24 +0000 Subject: * synchronous oneliner apps redesigned to offer Python generator-based API along with a more comprehensive set of accepted parameters. * massively documented (in Sphinx, NumPy style) --- .../ntfrcv/v2c-with-regexp-community-name.py | 88 ++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 examples/v3arch/asyncore/manager/ntfrcv/v2c-with-regexp-community-name.py (limited to 'examples/v3arch/asyncore/manager/ntfrcv/v2c-with-regexp-community-name.py') diff --git a/examples/v3arch/asyncore/manager/ntfrcv/v2c-with-regexp-community-name.py b/examples/v3arch/asyncore/manager/ntfrcv/v2c-with-regexp-community-name.py new file mode 100644 index 0000000..759bf98 --- /dev/null +++ b/examples/v3arch/asyncore/manager/ntfrcv/v2c-with-regexp-community-name.py @@ -0,0 +1,88 @@ +""" +Serve SNMP Community names defined by regexp +++++++++++++++++++++++++++++++++++++++++++++ + +Receive SNMP TRAP/INFORM messages with the following options: + +* SNMPv1/SNMPv2c +* with any SNMP community matching regexp '.*love.*' +* over IPv4/UDP, listening at 127.0.0.1:162 +* print received data on stdout + +Either of the following Net-SNMP commands will send notifications to this +receiver: + +| $ snmptrap -v1 -c rollover 127.0.0.1 1.3.6.1.4.1.20408.4.1.1.2 127.0.0.1 1 1 123 1.3.6.1.2.1.1.1.0 s test +| $ snmpinform -v2c -c glove 127.0.0.1 123 1.3.6.1.6.3.1.1.5.1 + +The Notification Receiver below taps on v1/v2c SNMP security module +to deliver certains values, normally internal to SNMP Engine, up to +the context of user application. + +This script examines the value of CommunityName, as it came from peer SNMP +Engine, and may modify it to match the only locally configured CommunityName +'public'. This effectively makes NotificationReceiver accepting messages with +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 +# to socket transport dispatcher +snmpEngine = engine.SnmpEngine() + +# Register a callback to be invoked at specified execution point of +# SNMP Engine and passed local variables at execution point's local scope. +# If at this execution point passed variables are modified, their new +# values will be propagated back and used by SNMP Engine for securityName +# selection. +def requestObserver(snmpEngine, execpoint, variables, cbCtx): + if re.match('.*love.*', str(variables['communityName'])): + print('Rewriting communityName \'%s\' from %s into \'public\'' % (variables['communityName'], ':'.join([str(x) for x in variables['transportInformation'][1]]))) + variables['communityName'] = variables['communityName'].clone('public') + +snmpEngine.observer.registerObserver( + requestObserver, + 'rfc2576.processIncomingMsg:writable' +) + +# Transport setup + +# UDP over IPv4 +config.addTransport( + snmpEngine, + udp.domainName, + udp.UdpTransport().openServerMode(('127.0.0.1', 162)) +) + +# SNMPv1/2c setup + +# SecurityName <-> CommunityName mapping +config.addV1System(snmpEngine, 'my-area', 'public') + +# Callback function for receiving notifications +def cbFun(snmpEngine, stateReference, contextEngineId, contextName, + varBinds, cbCtx): + print('Notification from ContextEngineId "%s", ContextName "%s"' % ( + contextEngineId.prettyPrint(), + contextName.prettyPrint() + ) + ) + for name, val in varBinds: + print('%s = %s' % (name.prettyPrint(), val.prettyPrint())) + +# Register SNMP Application at the SNMP engine +ntfrcv.NotificationReceiver(snmpEngine, cbFun) + +snmpEngine.transportDispatcher.jobStarted(1) # this job would never finish + +# Run I/O dispatcher which would receive queries and send confirmations +try: + snmpEngine.transportDispatcher.runDispatcher() +except: + snmpEngine.transportDispatcher.closeDispatcher() + raise -- cgit v1.2.1