ca-csr-create.py

#!/usr/bin/env python3

import datetime

from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives import serialization
from cryptography import x509
from cryptography.x509.oid import NameOID
from cryptography.hazmat.primitives import hashes

with open("/tmp/acme.key", "rb") as key_file:
    private_key = serialization.load_pem_private_key(
        key_file.read(),
        password=None,
        backend=default_backend()
    )

# Generate a CSR
csr = x509.CertificateSigningRequestBuilder()
csr = csr.subject_name(x509.Name([
    # Provide various details about who we are.
    x509.NameAttribute(NameOID.COUNTRY_NAME, "AR"),
    x509.NameAttribute(NameOID.STATE_OR_PROVINCE_NAME, "BA"),
    x509.NameAttribute(NameOID.LOCALITY_NAME, "Buenos Aires"),
    x509.NameAttribute(NameOID.ORGANIZATION_NAME, "ACME CORP"),
    x509.NameAttribute(NameOID.COMMON_NAME, "acme.com"),
    ])
)

# Sign the CSR with our private key.
csr = csr.sign(private_key, hashes.SHA256(), default_backend())

# Write our CSR out to disk.
with open("/tmp/acme.csr", "wb") as out:
    out.write(csr.public_bytes(serialization.Encoding.PEM))

print('Created /tmp/acme.csr')