snmptrap.py

from pysnmp.carrier.asyncore.dispatch import AsyncoreDispatcher
from pysnmp.carrier.asyncore.dgram import udp, udp6, unix
from pyasn1.codec.ber import decoder
from pysnmp.proto import api
import netifaces as ni

IPADDR=ni.ifaddresses('eth0')[2][0]['addr']
PORT=162

def toTime(s):
    d=s/86400
    s-=(86400*d)
    h=s/3600
    s-=(h*3600)
    m=s/60
    s-=(60*m)
    return d,h,m,s

# noinspection PyUnusedLocal
def cbFun(transportDispatcher, transportDomain, transportAddress, wholeMsg):
    while wholeMsg:
        msgVer = int(api.decodeMessageVersion(wholeMsg))
        if msgVer in api.protoModules:
            pMod = api.protoModules[msgVer]
        else:
            print('Unsupported SNMP version %s' % msgVer)
            return
        reqMsg, wholeMsg = decoder.decode(
            wholeMsg, asn1Spec=pMod.Message(),
        )
        print('Notification message from %s:%s: ' % (
            transportDomain, transportAddress
        )
              )
        reqPDU = pMod.apiMessage.getPDU(reqMsg)
        if reqPDU.isSameTypeWith(pMod.TrapPDU()):
            if msgVer == api.protoVersion1:
                print('Enterprise: %s' % (pMod.apiTrapPDU.getEnterprise(reqPDU).prettyPrint()))
                print('Agent Address: %s' % (pMod.apiTrapPDU.getAgentAddr(reqPDU).prettyPrint()))
                print('Generic Trap: %s' % (pMod.apiTrapPDU.getGenericTrap(reqPDU).prettyPrint()))
                print('Specific Trap: %s' % (pMod.apiTrapPDU.getSpecificTrap(reqPDU).prettyPrint()))
                print('Uptime: %s' % (pMod.apiTrapPDU.getTimeStamp(reqPDU).prettyPrint()))
                varBinds = pMod.apiTrapPDU.getVarBindList(reqPDU)
            else:
                varBinds = pMod.apiPDU.getVarBindList(reqPDU)
            print('Var-binds:')
            for oid, val in varBinds:
                print('%s = %s' % (oid.prettyPrint(), val.prettyPrint()))
    return wholeMsg


transportDispatcher = AsyncoreDispatcher()

transportDispatcher.registerRecvCbFun(cbFun)

# UDP/IPv4
transportDispatcher.registerTransport(
    udp.domainName, udp.UdpSocketTransport().openServerMode((IPADDR, PORT))
)

transportDispatcher.jobStarted(1)

try:
    # Dispatcher will never finish as job#1 never reaches zero
    transportDispatcher.runDispatcher()
except:
    transportDispatcher.closeDispatcher()
    raise