check_ipv6ra

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

import argparse
import sys
import os
import subprocess

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

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

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)

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

def doipv6racall(interface,expected,ignored):
    infomsg("expected: "+str(expected))
    infomsg("ignored: "+str(ignored))

    cmdline = ["/usr/bin/rdisc6","--numeric","--quiet","--multiple","10",interface]
    completedproc = subprocess.run(cmdline,capture_output=True)
    output = completedproc.stdout.decode("utf-8")
    errors = completedproc.stderr.decode("utf-8")
    response = completedproc.returncode
    infomsg(output)
    rafound = []
    if response == 0:
        alllines = output.splitlines()
        for line in alllines:
            line = line.strip()
            if line!="":
                if line not in rafound:
                    rafound.append(line)
    infomsg(rafound)

    missing = []
    for item in expected:
        if (item not in rafound) and (item not in ignored):
            missing.append(item)

    unexpected = []
    for item in rafound:
        if (item not in expected) and (item not in ignored):
            unexpected.append(item)

    count_missing = len(missing)
    count_unexpected = len(unexpected)
    if count_missing==0 and count_unexpected==0:
        exitnagios("OK","The found ipv6 RA are as expected - "+str(expected)+" | missing=0 unexpected=0")
    else:
        messages = []
        if count_missing>0:
            messages.append("There are missing RA - "+str(missing))
        if count_unexpected>0:
            messages.append("There are unexpected RA - "+str(unexpected))
        exitnagios("CRITICAL"," --- ".join(messages)+" | missing="+str(count_missing)+" unexpected="+str(count_unexpected))

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

#collect arguments
def parse_args():
    parser = argparse.ArgumentParser()
    parser.add_argument("-i", "--interface",         action="store",       dest="interface",        default="",                                   help="interface to evaluate")
    parser.add_argument("-e", "--expected",          action="store",       dest="expected",         default="",                                   help="expected RA prefixes")
    parser.add_argument("-g", "--ignored",           action="store",       dest="ignored",          default="",                                   help="ignore these RA prefixes")
    parser.add_argument("-®", "--debug",             action="store_true",  dest="debug",            default=False,                                help="be more verbose")
    args = parser.parse_args()

    return args

def main():
    args = parse_args()
    setcandebug(args.debug)

    if args.interface=="":
        exitnagios("CRITICAL","no interface selected")

    expected = args.expected.split(",")
    if "" in expected:
        expected.remove("")
    if None in expected:
        expected.remove(None)
    ignored = args.ignored.split(",")
    if "" in ignored:
        ignored.remove("")
    if None in ignored:
        ignored.remove(None)
    doipv6racall(args.interface,expected,ignored)

if __name__ == "__main__":
    main()

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