A script to check to the lifetime of a rrsig

check_rrsig.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
import subprocess
import re
import datetime

def main():
    if (len(sys.argv) != 2):
        print "please specify a zone"
        return
    command = "dig +noall +answer +dnssec -t rrsig +cd %s" % (sys.argv[1])
    results = subprocess.check_output(command,shell=True)
    lines = results.split("\n")
    timetoexpire = 200
    for line in lines:
        elements = re.split("\s",line)
        if (len(elements) == 26):
            format = "%Y%m%d%H%M%S"
            now = datetime.datetime.now()
            minexpire = datetime.datetime.strptime(elements[10], format)
            maxexpire = datetime.datetime.strptime(elements[9], format)
            if ((maxexpire-now).days < timetoexpire):
                timetoexpire = (maxexpire-now).days

    print timetoexpire

if __name__ == "__main__":
    main()