python-csr/csr_tools/csrgen35.py

143 lines
4.5 KiB
Python
Executable File

#!/usr/bin/env python3
#
# Generate a key, self-signed certificate, and certificate request.
# Usage: csrgen <fqdn>
#
# When more than one hostname is provided, a SAN (Subject Alternate Name)
# certificate and request are generated. This can be acheived by adding -s.
# Usage: csrgen <hostname> -s <san0> <san1>
#
# Author: Courtney Cotton <cotton@cottoncourtney.com> 06-25-2014
# mod'd for python 3.5
# Libraries/Modules
from OpenSSL import crypto, SSL
import argparse
import yaml
# Generate Certificate Signing Request (CSR)
def generateCSR(nodename, sans=[]):
while True:
C = input("Enter your Country Name (2 letter code) [US]: ")
if len(C) != 2:
print("You must enter two letters. You entered %r" % (C))
continue
ST = input("Enter your State or Province <full name> []:California: ")
if len(ST) == 0:
print("Please enter your State or Province.")
continue
L = input("Enter your (Locality Name (eg, city) []:San Francisco: ")
if len(L) == 0:
print("Please enter your City.")
continue
O = input("Enter your Organization Name (eg, company) []:FTW Enterprise: ")
if len(L) == 0:
print("Please enter your Organization Name.")
continue
OU = input("Enter your Organizational Unit (eg, section) []:IT: ")
if len(OU) == 0:
print("Please enter your OU.")
continue
# Allows you to permanently set values required for CSR
# To use, comment raw_input and uncomment this section.
# C = 'US'
# ST = 'New York'
# L = 'Location'
# O = 'Organization'
# OU = 'Organizational Unit'
csrfile = 'host.csr'
keyfile = 'host.key'
TYPE_RSA = crypto.TYPE_RSA
# Appends SAN to have 'DNS:'
ss = []
for i in sans:
ss.append("DNS: %s" % i)
ss = ", ".join(ss)
req = crypto.X509Req()
req.get_subject().CN = nodename
req.get_subject().countryName = C
req.get_subject().stateOrProvinceName = ST
req.get_subject().localityName = L
req.get_subject().organizationName = O
req.get_subject().organizationalUnitName = OU
# Add in extensions
# added bytearray to string
# before -> "keyUsage"
# after -> b"keyUsage"
base_constraints = ([
crypto.X509Extension(b"keyUsage", False, b"Digital Signature, Non Repudiation, Key Encipherment"),
crypto.X509Extension(b"basicConstraints", False, b"CA:FALSE"),
])
x509_extensions = base_constraints
# If there are SAN entries, append the base_constraints to include them.
if ss:
san_constraint = crypto.X509Extension(b"subjectAltName", False, ss)
x509_extensions.append(san_constraint)
req.add_extensions(x509_extensions)
# Utilizes generateKey function to kick off key generation.
key = generateKey(TYPE_RSA, 2048)
req.set_pubkey(key)
# change to sha 256?
# req.sign(key, "sha1")
req.sign(key, "sha256")
generateFiles(csrfile, req)
generateFiles(keyfile, key)
return req
# Generate Private Key
def generateKey(type, bits):
key = crypto.PKey()
key.generate_key(type, bits)
return key
# Generate .csr/key files.
def generateFiles(mkFile, request):
if mkFile == 'host.csr':
f = open(mkFile, "wb")
f.write(crypto.dump_certificate_request(crypto.FILETYPE_PEM, request))
f.close()
# print test
#print(crypto.dump_certificate_request(crypto.FILETYPE_PEM, request))
elif mkFile == 'host.key':
f = open(mkFile, "wb")
f.write(crypto.dump_privatekey(crypto.FILETYPE_PEM, request))
f.close()
else:
print("Failed.")
exit()
# Run Portion
# This section will parse the flags available via command line.
parser = argparse.ArgumentParser()
parser.add_argument("name", help="Provide the FQDN", action="store")
parser.add_argument("-f", "--file", help="Configuration file", action="store", nargs='*', default="")
parser.add_argument("-s", "--san", help="SANS", action="store", nargs='*', default="")
args = parser.parse_args()
# Variables from CLI Parser (Argparse)
hostname = args.name
sans = args.san
config_file = args.file
# Run the primary function(s) based on input.
if config_file is None:
generateFromFile(config_file)
else:
generateCSR(hostname,sans)