takes an SSHFP record and converts to tinydns format

tinysshfp.py

#!/usr/bin/env python

# tinysshfp - takes the output of "ssh-keygen -r" and converts into tinydns
#
# example: ssh-keygen -r example.com | ./tinysshfp.py 
#
# 2017 Lee Maguire

import getopt
import sys
import re

ttl = ""

def tinySshfpRecord( hostname, algid, fptype, fp, ttl ):
  fpout = ""
  for c in range(0, len(fp), 2):     
     fpout = fpout + "\\{0:03o}".format(int("0x"+fp[c]+fp[c+1],16))
  return(":" + hostname + ":44:" + "\\{0:03o}".format(int(algid)) + "\\{0:03o}".format(int(fptype)) + fpout + ":" + ttl);

opts, args = getopt.getopt(sys.argv[1:],"ht:",["ttl="])
for opt, arg in opts:
  if opt == '-h':
    print 'Usage: tinysshfp.py -t 60'
    sys.exit()
  elif opt in ("-t", "--ttl"):
    ttl = arg

for input_text in sys.stdin:
  hostname,xin,xsshfp,algid,fptype,fp = input_text.rstrip().split(" ")
  line = tinySshfpRecord( hostname, algid, fptype, fp, ttl )
  sys.stdout.write( line + "\n")

sys.exit(0)