check_snmp_ports

#!/usr/bin/env python3
#-------------------------------------------------------------------------------

import argparse
import sys
import re
import subprocess
import datetime
import socket

#-------------------------------------------------------------------------------

_candebug = False
def candebug():
    global _candebug
    return _candebug
def setcandebug(value):
    global _candebug
    _candebug = value

def infomsg(msg):
    if candebug() == True:
        print(msg, flush=True)

def exitnagios(status,message):
    if status=="OK":
        exitcode = 0
    elif status=="WARNING":
        exitcode = 1
    elif status=="CRITICAL":
        exitcode = 2
    elif status=="UNKNOWN":
        exitcode = 3
    else:
        exitcode = 4
    print(status+": "+message, flush=True)
    sys.exit(exitcode)

#-------------------------------------------------------------------------------

original_getaddrinfo = socket.getaddrinfo

def forced_ipv6_gai_family(*args, **kwargs):
    global original_getaddrinfo
    responses = original_getaddrinfo(*args, **kwargs)
    return [response
            for response in responses
            if response[0] == socket.AF_INET6]

def forced_ipv4_gai_family(*args, **kwargs):
    global original_getaddrinfo
    responses = original_getaddrinfo(*args, **kwargs)
    return [response
            for response in responses
            if response[0] == socket.AF_INET]

#-------------------------------------------------------------------------------

def dosnmpuptimecall(listports, expected, hostname, port, community, timeoutvalue, timeoutstatus):
    found = {}
    token = "iso.3.6.1.2.1.2.2.1.5."
    exitcode, stdout = snmpget(hostname, port, community, ".1.3.6.1.2.1.2.2.1.5")
    if exitcode==None:
        exitnagios(timeoutstatus,"Timeout")
    elif exitcode==0:
        for line in stdout.strip().splitlines():
            if line.startswith(token):
                parsing = line[len(token):]
                parts = parsing.split("=",1)
                port=parts[0].strip()
                payload=parts[1].strip().split()
                found[port]=payload[1]
    else:
        exitnagios("CRITICAL","Unexpected scenario")

    infomsg(found)
    validports = listports.split(",")
    infomsg(validports)
    errors = {}
    success = {}
    for testport in validports:
        if testport in found.keys():
            current = found[testport]
            if current==expected:
                success[testport] = current
            else:
                errors[testport] = current
        else:
            errors[testport] = "?"

    if len(errors)==0:
        exitnagios("OK","all ports as expected "+str(success))
    else:
        exitnagios("CRITICAL","some ports are not expected "+str(errors)+" - "+str(success))

def snmpget(hostname, port, community, oid):
    cmdline = ["/usr/bin/snmpwalk","-v","2c","-c",community,hostname+":"+str(port),oid]
    completedproc = subprocess.run(cmdline,capture_output=True)
    output = completedproc.stdout.decode("utf-8").strip()
    errors = completedproc.stderr.decode("utf-8").strip()
    exitcode = completedproc.returncode
    if errors.startswith("Timeout: No Response from "):
        exitcode = None
        output = None

    return (exitcode, output)

#-------------------------------------------------------------------------------

def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("-H", "--hostname",                                dest="hostname",         default="",                                   help="server to check")
    parser.add_argument("-p", "--port",                                    dest="port",             default=161,                                  help="port to use, usually 143 or 993")
    parser.add_argument("-t", "--timeout",                                 dest="timeout",          default="30:CRITICAL",                        help="timeout value:STATUS")
    parser.add_argument("-m", "--community",                               dest="community",        default="public",                             help="private/public")
    parser.add_argument("-l", "--listports",                               dest="listports",        default="",                                   help="comma separated list of ports to check speed")
    parser.add_argument("-e", "--expected",                                dest="expected",         default="",                                   help="expected speed")
    parser.add_argument("-®", "--debug",             action="store_true",  dest="debug",            default=False,                                help="be more verbose")
    args = parser.parse_args()

    setcandebug(args.debug)

    if args.hostname == "":
        exitnagios("CRITICAL","no hostname specified")

    parts = args.timeout.split(":")
    timeoutvalue = int(parts[0])
    if len(parts)>1:
        timeoutstatus = parts[1]
    else:
        timeoutstatus = "CRITICAL"
    if timeoutstatus in ["OK", "WARNING", "CRITICAL", "UNKNOWN"]:
        dosnmpuptimecall(args.listports,args.expected,args.hostname,int(args.port),args.community,timeoutvalue,timeoutstatus)
    else:
        exitnagios("CRITICAL","timeout status is not valid")

if __name__ == "__main__":
    main()

#-------------------------------------------------------------------------------

#timeout
#warning