#!/usr/bin/env python

import sys
import base64

# 'openssl x509 -text -in cert.pem' to get the infos
def usage():
    print("Usage: %s Key-Identifier Serial-Number " % sys.argv[0], file=sys.stderr)

if len(sys.argv) != 3:
    usage()
    sys.exit(1)

# 509v3 Authority Key Identifier, for instance 69:88:5B:6B:87:46:40:41:E1:B3:7B:84:7B:A0:AE:2C:DE:01:C8:D4
keyIdS = sys.argv[1]
keyId = bytes.fromhex(keyIdS.replace(":", "")) # Thanks to ChatGPT
keyIdE = base64.urlsafe_b64encode(keyId).decode().strip("=")

# Serial Number
serialNumberS = sys.argv[2]
serialNumber = bytes.fromhex(serialNumberS.replace(":", ""))
serialNumberE = base64.urlsafe_b64encode(serialNumber).decode().strip("=")

path = keyIdE + "." + serialNumberE

print(path)