Various SNMP versions
*********************


Multiple SNMP USM users
=======================

Receive SNMP TRAP/INFORM messages with the following options:

* SNMPv3

* with USM users:
     * 'usr-md5-des', auth: MD5, priv DES, ContextEngineId:
       8000000001020304

     * 'usr-md5-none', auth: MD5, priv NONE, ContextEngineId:
       8000000001020304

     * 'usr-sha-aes128', auth: SHA, priv AES, ContextEngineId:
       8000000001020304

* over IPv4/UDP, listening at 127.0.0.1:162

* using Twisted framework for network transport

* print received data on stdout

Either of the following Net-SNMP commands will send notifications to
this receiver:

   $ snmptrap -v3 -u usr-md5-des -l authPriv -A authkey1 -X privkey1 -e 8000000001020304 127.0.0.1 123 1.3.6.1.6.3.1.1.5.1
   $ snmptrap -v3 -u usr-md5-none -l authNoPriv -A authkey1 -e 8000000001020304 127.0.0.1 123 1.3.6.1.6.3.1.1.5.1
   $ snmpinform -v3 -u usr-sha-aes128 -l authPriv -a SHA -A authkey1 -x AES -X privkey1 127.0.0.1 123 1.3.6.1.6.3.1.1.5.1

   from twisted.internet import reactor
   from pysnmp.entity import engine, config
   from pysnmp.carrier.twisted.dgram import udp
   from pysnmp.entity.rfc3413 import ntfrcv
   from pysnmp.proto import rfc1902

   # Create SNMP engine with autogenernated engineID and pre-bound
   # to socket transport dispatcher
   snmpEngine = engine.SnmpEngine()

   # Transport setup

   # UDP over IPv4
   config.addTransport(
       snmpEngine,
       udp.domainName,
       udp.UdpTwistedTransport().openServerMode(('127.0.0.1', 162))
   )

   # -- begin of SNMPv3/USM setup

   # user: usr-md5-des, auth: MD5, priv DES
   config.addV3User(
       snmpEngine, 'usr-md5-des',
       config.usmHMACMD5AuthProtocol, 'authkey1',
       config.usmDESPrivProtocol, 'privkey1'
   )

   # user: usr-md5-des, auth: MD5, priv DES, securityEngineId: 8000000001020304
   # this USM entry is used for TRAP receiving purposes
   config.addV3User(
       snmpEngine, 'usr-md5-des',
       config.usmHMACMD5AuthProtocol, 'authkey1',
       config.usmDESPrivProtocol, 'privkey1',
       securityEngineId=rfc1902.OctetString(hexValue='8000000001020304')
   )

   # user: usr-md5-none, auth: MD5, priv NONE
   config.addV3User(
       snmpEngine, 'usr-md5-none',
       config.usmHMACMD5AuthProtocol, 'authkey1'
   )

   # user: usr-md5-none, auth: MD5, priv NONE, securityEngineId: 8000000001020304
   # this USM entry is used for TRAP receiving purposes
   config.addV3User(
       snmpEngine, 'usr-md5-none',
       config.usmHMACMD5AuthProtocol, 'authkey1',
       securityEngineId=rfc1902.OctetString(hexValue='8000000001020304')
   )

   # user: usr-sha-aes128, auth: SHA, priv AES
   config.addV3User(
       snmpEngine, 'usr-sha-aes128',
       config.usmHMACSHAAuthProtocol, 'authkey1',
       config.usmAesCfb128Protocol, 'privkey1'
   )

   # user: usr-sha-aes128, auth: SHA, priv AES, securityEngineId: 8000000001020304
   # this USM entry is used for TRAP receiving purposes
   config.addV3User(
       snmpEngine, 'usr-sha-aes128',
       config.usmHMACSHAAuthProtocol, 'authkey1',
       config.usmAesCfb128Protocol, 'privkey1',
       securityEngineId=rfc1902.OctetString(hexValue='8000000001020304')
   )


   # -- end of SNMPv3/USM setup

   # Callback function for receiving notifications
   # noinspection PyUnusedLocal,PyUnusedLocal,PyUnusedLocal
   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)

   # Run Twisted main loop
   reactor.run()

"Download" script.

See also: library reference.
