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@gdamjan
Last active April 14, 2024 07:16
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Python script to check on SSL certificates
# -*- encoding: utf-8 -*-
# requires a recent enough python with idna support in socket
# pyopenssl, cryptography and idna
from OpenSSL import SSL
from cryptography import x509
from cryptography.x509.oid import NameOID
import idna
from socket import socket
from collections import namedtuple
HostInfo = namedtuple(field_names='cert hostname peername', typename='HostInfo')
HOSTS = [
('damjan.softver.org.mk', 443),
('expired.badssl.com', 443),
('wrong.host.badssl.com', 443),
('ca.ocsr.nl', 443),
('faß.de', 443),
('самодеј.мкд', 443),
]
def verify_cert(cert, hostname):
# verify notAfter/notBefore, CA trusted, servername/sni/hostname
cert.has_expired()
# service_identity.pyopenssl.verify_hostname(client_ssl, hostname)
# issuer
def get_certificate(hostname, port):
hostname_idna = idna.encode(hostname)
sock = socket()
sock.connect((hostname, port))
peername = sock.getpeername()
ctx = SSL.Context(SSL.SSLv23_METHOD) # most compatible
ctx.check_hostname = False
ctx.verify_mode = SSL.VERIFY_NONE
sock_ssl = SSL.Connection(ctx, sock)
sock_ssl.set_connect_state()
sock_ssl.set_tlsext_host_name(hostname_idna)
sock_ssl.do_handshake()
cert = sock_ssl.get_peer_certificate()
crypto_cert = cert.to_cryptography()
sock_ssl.close()
sock.close()
return HostInfo(cert=crypto_cert, peername=peername, hostname=hostname)
def get_alt_names(cert):
try:
ext = cert.extensions.get_extension_for_class(x509.SubjectAlternativeName)
return ext.value.get_values_for_type(x509.DNSName)
except x509.ExtensionNotFound:
return None
def get_common_name(cert):
try:
names = cert.subject.get_attributes_for_oid(NameOID.COMMON_NAME)
return names[0].value
except x509.ExtensionNotFound:
return None
def get_issuer(cert):
try:
names = cert.issuer.get_attributes_for_oid(NameOID.COMMON_NAME)
return names[0].value
except x509.ExtensionNotFound:
return None
def print_basic_info(hostinfo):
s = '''» {hostname} « … {peername}
\tcommonName: {commonname}
\tSAN: {SAN}
\tissuer: {issuer}
\tnotBefore: {notbefore}
\tnotAfter: {notafter}
'''.format(
hostname=hostinfo.hostname,
peername=hostinfo.peername,
commonname=get_common_name(hostinfo.cert),
SAN=get_alt_names(hostinfo.cert),
issuer=get_issuer(hostinfo.cert),
notbefore=hostinfo.cert.not_valid_before,
notafter=hostinfo.cert.not_valid_after
)
print(s)
def check_it_out(hostname, port):
hostinfo = get_certificate(hostname, port)
print_basic_info(hostinfo)
import concurrent.futures
if __name__ == '__main__':
with concurrent.futures.ThreadPoolExecutor(max_workers=4) as e:
for hostinfo in e.map(lambda x: get_certificate(x[0], x[1]), HOSTS):
print_basic_info(hostinfo)
@panofish
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I really appreciate that you took the time to share this with the world... super useful !!! Thank you.

@leejhn
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leejhn commented May 11, 2023

Thank you so much for being so helpful.

@dynamicdeploy
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cert.has_expired() doesn't work for this version. Is there a workaround?
Error
'cryptography.hazmat.bindings._rust.x509.Certificat' object has no attribute 'has_expired'

@gdamjan
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Author

gdamjan commented Jul 26, 2023

cert.has_expired() doesn't work for this version.

and what is "this" version !?!

Is there a workaround?

install "another" version?!

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