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mailinabox/management/ssl_certificates.py
Joshua Tauberer 37dad9d4bb Provision certificates from Let's Encrypt grouped by DNS zone
Folks didn't want certificates exposing all of the domains hosted by the server (although this can already be found on the internet).

Additionally, if one domain fails (usually because of a misconfiguration), it would be nice if not everything fails. So grouping them helps with that.

Fixes #690.
2020-05-29 15:38:18 -04:00

687 lines
26 KiB
Python
Executable File

#!/usr/local/lib/mailinabox/env/bin/python
# Utilities for installing and selecting SSL certificates.
import os, os.path, re, shutil, subprocess, tempfile
from utils import shell, safe_domain_name, sort_domains
import idna
# SELECTING SSL CERTIFICATES FOR USE IN WEB
def get_ssl_certificates(env):
# Scan all of the installed SSL certificates and map every domain
# that the certificates are good for to the best certificate for
# the domain.
from cryptography.hazmat.primitives.asymmetric.rsa import RSAPrivateKey
from cryptography.x509 import Certificate
# The certificates are all stored here:
ssl_root = os.path.join(env["STORAGE_ROOT"], 'ssl')
# List all of the files in the SSL directory and one level deep.
def get_file_list():
if not os.path.exists(ssl_root):
return
for fn in os.listdir(ssl_root):
if fn == 'ssl_certificate.pem':
# This is always a symbolic link
# to the certificate to use for
# PRIMARY_HOSTNAME. Don't let it
# be eligible for use because we
# could end up creating a symlink
# to itself --- we want to find
# the cert that it should be a
# symlink to.
continue
fn = os.path.join(ssl_root, fn)
if os.path.isfile(fn):
yield fn
elif os.path.isdir(fn):
for fn1 in os.listdir(fn):
fn1 = os.path.join(fn, fn1)
if os.path.isfile(fn1):
yield fn1
# Remember stuff.
private_keys = { }
certificates = [ ]
# Scan each of the files to find private keys and certificates.
# We must load all of the private keys first before processing
# certificates so that we can check that we have a private key
# available before using a certificate.
for fn in get_file_list():
try:
pem = load_pem(load_cert_chain(fn)[0])
except ValueError:
# Not a valid PEM format for a PEM type we care about.
continue
# Remember where we got this object.
pem._filename = fn
# Is it a private key?
if isinstance(pem, RSAPrivateKey):
private_keys[pem.public_key().public_numbers()] = pem
# Is it a certificate?
if isinstance(pem, Certificate):
certificates.append(pem)
# Process the certificates.
domains = { }
for cert in certificates:
# What domains is this certificate good for?
cert_domains, primary_domain = get_certificate_domains(cert)
cert._primary_domain = primary_domain
# Is there a private key file for this certificate?
private_key = private_keys.get(cert.public_key().public_numbers())
if not private_key:
continue
cert._private_key = private_key
# Add this cert to the list of certs usable for the domains.
for domain in cert_domains:
# The primary hostname can only use a certificate mapped
# to the system private key.
if domain == env['PRIMARY_HOSTNAME']:
if cert._private_key._filename != os.path.join(env['STORAGE_ROOT'], 'ssl', 'ssl_private_key.pem'):
continue
domains.setdefault(domain, []).append(cert)
# Sort the certificates to prefer good ones.
import datetime
now = datetime.datetime.utcnow()
ret = { }
for domain, cert_list in domains.items():
#for c in cert_list: print(domain, c.not_valid_before, c.not_valid_after, "("+str(now)+")", c.issuer, c.subject, c._filename)
cert_list.sort(key = lambda cert : (
# must be valid NOW
cert.not_valid_before <= now <= cert.not_valid_after,
# prefer one that is not self-signed
cert.issuer != cert.subject,
###########################################################
# The above lines ensure that valid certificates are chosen
# over invalid certificates. The lines below choose between
# multiple valid certificates available for this domain.
###########################################################
# prefer one with the expiration furthest into the future so
# that we can easily rotate to new certs as we get them
cert.not_valid_after,
###########################################################
# We always choose the certificate that is good for the
# longest period of time. This is important for how we
# provision certificates for Let's Encrypt. To ensure that
# we don't re-provision every night, we have to ensure that
# if we choose to provison a certificate that it will
# *actually* be used so the provisioning logic knows it
# doesn't still need to provision a certificate for the
# domain.
###########################################################
# in case a certificate is installed in multiple paths,
# prefer the... lexicographically last one?
cert._filename,
), reverse=True)
cert = cert_list.pop(0)
ret[domain] = {
"private-key": cert._private_key._filename,
"certificate": cert._filename,
"primary-domain": cert._primary_domain,
"certificate_object": cert,
}
return ret
def get_domain_ssl_files(domain, ssl_certificates, env, allow_missing_cert=False, use_main_cert=True):
if use_main_cert or not allow_missing_cert:
# Get the system certificate info.
ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_certificate.pem'))
system_certificate = {
"private-key": ssl_private_key,
"certificate": ssl_certificate,
"primary-domain": env['PRIMARY_HOSTNAME'],
"certificate_object": load_pem(load_cert_chain(ssl_certificate)[0]),
}
if use_main_cert:
if domain == env['PRIMARY_HOSTNAME']:
# The primary domain must use the server certificate because
# it is hard-coded in some service configuration files.
return system_certificate
wildcard_domain = re.sub("^[^\.]+", "*", domain)
if domain in ssl_certificates:
return ssl_certificates[domain]
elif wildcard_domain in ssl_certificates:
return ssl_certificates[wildcard_domain]
elif not allow_missing_cert:
# No valid certificate is available for this domain! Return default files.
return system_certificate
else:
# No valid certificate is available for this domain.
return None
# PROVISIONING CERTIFICATES FROM LETSENCRYPT
def get_certificates_to_provision(env, limit_domains=None, show_valid_certs=True):
# Get a set of domain names that we can provision certificates for
# using certbot. We start with domains that the box is serving web
# for and subtract:
# * domains not in limit_domains if limit_domains is not empty
# * domains with custom "A" records, i.e. they are hosted elsewhere
# * domains with actual "A" records that point elsewhere (misconfiguration)
# * domains that already have certificates that will be valid for a while
from web_update import get_web_domains
from status_checks import query_dns, normalize_ip
existing_certs = get_ssl_certificates(env)
plausible_web_domains = get_web_domains(env, exclude_dns_elsewhere=False)
actual_web_domains = get_web_domains(env)
domains_to_provision = set()
domains_cant_provision = { }
for domain in plausible_web_domains:
# Skip domains that the user doesn't want to provision now.
if limit_domains and domain not in limit_domains:
continue
# Check that there isn't an explicit A/AAAA record.
if domain not in actual_web_domains:
domains_cant_provision[domain] = "The domain has a custom DNS A/AAAA record that points the domain elsewhere, so there is no point to installing a TLS certificate here and we could not automatically provision one anyway because provisioning requires access to the website (which isn't here)."
# Check that the DNS resolves to here.
else:
# Does the domain resolve to this machine in public DNS? If not,
# we can't do domain control validation. For IPv6 is configured,
# make sure both IPv4 and IPv6 are correct because we don't know
# how Let's Encrypt will connect.
bad_dns = []
for rtype, value in [("A", env["PUBLIC_IP"]), ("AAAA", env.get("PUBLIC_IPV6"))]:
if not value: continue # IPv6 is not configured
response = query_dns(domain, rtype)
if response != normalize_ip(value):
bad_dns.append("%s (%s)" % (response, rtype))
if bad_dns:
domains_cant_provision[domain] = "The domain name does not resolve to this machine: " \
+ (", ".join(bad_dns)) \
+ "."
else:
# DNS is all good.
# Check for a good existing cert.
existing_cert = get_domain_ssl_files(domain, existing_certs, env, use_main_cert=False, allow_missing_cert=True)
if existing_cert:
existing_cert_check = check_certificate(domain, existing_cert['certificate'], existing_cert['private-key'],
warn_if_expiring_soon=14)
if existing_cert_check[0] == "OK":
if show_valid_certs:
domains_cant_provision[domain] = "The domain has a valid certificate already. ({} Certificate: {}, private key {})".format(
existing_cert_check[1],
existing_cert['certificate'],
existing_cert['private-key'])
continue
domains_to_provision.add(domain)
return (domains_to_provision, domains_cant_provision)
def provision_certificates(env, limit_domains):
# What domains should we provision certificates for? And what
# errors prevent provisioning for other domains.
domains, domains_cant_provision = get_certificates_to_provision(env, limit_domains=limit_domains)
# Build a list of what happened on each domain or domain-set.
ret = []
for domain, error in domains_cant_provision.items():
ret.append({
"domains": [domain],
"log": [error],
"result": "skipped",
})
# Break into groups by DNS zone: Group every domain with its parent domain, if
# its parent domain is in the list of domains to request a certificate for.
# Start with the zones so that if the zone doesn't need a certificate itself,
# its children will still be grouped together. Sort the provision domains to
# put parents ahead of children.
# Since Let's Encrypt requests are limited to 100 domains at a time,
# we'll create a list of lists of domains where the inner lists have
# at most 100 items. By sorting we also get the DNS zone domain as the first
# entry in each list (unless we overflow beyond 100) which ends up as the
# primary domain listed in each certificate.
from dns_update import get_dns_zones
certs = { }
for zone, zonefile in get_dns_zones(env):
certs[zone] = [[]]
for domain in sort_domains(domains, env):
# Does the domain end with any domain we've seen so far.
for parent in certs.keys():
if domain.endswith("." + parent):
# Add this to the parent's list of domains.
# Start a new group if the list already has
# 100 items.
if len(certs[parent][-1]) == 100:
certs[parent].append([])
certs[parent][-1].append(domain)
break
else:
# This domain is not a child of any domain we've seen yet, so
# start a new group. This shouldn't happen since every zone
# was already added.
certs[domain] = [[domain]]
# Flatten to a list of lists of domains (from a mapping). Remove empty
# lists (zones with no domains that need certs).
certs = sum(certs.values(), [])
certs = [_ for _ in certs if len(_) > 0]
# Prepare to provision.
# Where should we put our Let's Encrypt account info and state cache.
account_path = os.path.join(env['STORAGE_ROOT'], 'ssl/lets_encrypt')
if not os.path.exists(account_path):
os.mkdir(account_path)
# Provision certificates.
for domain_list in certs:
ret.append({
"domains": domain_list,
"log": [],
})
try:
# Create a CSR file for our master private key so that certbot
# uses our private key.
key_file = os.path.join(env['STORAGE_ROOT'], 'ssl', 'ssl_private_key.pem')
with tempfile.NamedTemporaryFile() as csr_file:
# We could use openssl, but certbot requires
# that the CN domain and SAN domains match
# the domain list passed to certbot, and adding
# SAN domains openssl req is ridiculously complicated.
# subprocess.check_output([
# "openssl", "req", "-new",
# "-key", key_file,
# "-out", csr_file.name,
# "-subj", "/CN=" + domain_list[0],
# "-sha256" ])
from cryptography import x509
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.serialization import Encoding
from cryptography.hazmat.primitives import hashes
from cryptography.x509.oid import NameOID
builder = x509.CertificateSigningRequestBuilder()
builder = builder.subject_name(x509.Name([ x509.NameAttribute(NameOID.COMMON_NAME, domain_list[0]) ]))
builder = builder.add_extension(x509.BasicConstraints(ca=False, path_length=None), critical=True)
builder = builder.add_extension(x509.SubjectAlternativeName(
[x509.DNSName(d) for d in domain_list]
), critical=False)
request = builder.sign(load_pem(load_cert_chain(key_file)[0]), hashes.SHA256(), default_backend())
with open(csr_file.name, "wb") as f:
f.write(request.public_bytes(Encoding.PEM))
# Provision, writing to a temporary file.
webroot = os.path.join(account_path, 'webroot')
os.makedirs(webroot, exist_ok=True)
with tempfile.TemporaryDirectory() as d:
cert_file = os.path.join(d, 'cert_and_chain.pem')
print("Provisioning TLS certificates for " + ", ".join(domain_list) + ".")
certbotret = subprocess.check_output([
"certbot",
"certonly",
#"-v", # just enough to see ACME errors
"--non-interactive", # will fail if user hasn't registered during Mail-in-a-Box setup
"-d", ",".join(domain_list), # first will be main domain
"--csr", csr_file.name, # use our private key; unfortunately this doesn't work with auto-renew so we need to save cert manually
"--cert-path", os.path.join(d, 'cert'), # we only use the full chain
"--chain-path", os.path.join(d, 'chain'), # we only use the full chain
"--fullchain-path", cert_file,
"--webroot", "--webroot-path", webroot,
"--config-dir", account_path,
#"--staging",
], stderr=subprocess.STDOUT).decode("utf8")
install_cert_copy_file(cert_file, env)
ret[-1]["log"].append(certbotret)
ret[-1]["result"] = "installed"
except subprocess.CalledProcessError as e:
ret[-1]["log"].append(e.output.decode("utf8"))
ret[-1]["result"] = "error"
except Exception as e:
ret[-1]["log"].append(str(e))
ret[-1]["result"] = "error"
# Run post-install steps.
ret.extend(post_install_func(env))
# Return what happened with each certificate request.
return ret
def provision_certificates_cmdline():
import sys
from exclusiveprocess import Lock
from utils import load_environment
Lock(die=True).forever()
env = load_environment()
quiet = False
domains = []
for arg in sys.argv[1:]:
if arg == "-q":
quiet = True
else:
domains.append(arg)
# Go.
status = provision_certificates(env, limit_domains=domains)
# Show what happened.
for request in status:
if isinstance(request, str):
print(request)
else:
if quiet and request['result'] == 'skipped':
continue
print(request['result'] + ":", ", ".join(request['domains']) + ":")
for line in request["log"]:
print(line)
print()
# INSTALLING A NEW CERTIFICATE FROM THE CONTROL PANEL
def create_csr(domain, ssl_key, country_code, env):
return shell("check_output", [
"openssl", "req", "-new",
"-key", ssl_key,
"-sha256",
"-subj", "/C=%s/CN=%s" % (country_code, domain)])
def install_cert(domain, ssl_cert, ssl_chain, env, raw=False):
# Write the combined cert+chain to a temporary path and validate that it is OK.
# The certificate always goes above the chain.
import tempfile
fd, fn = tempfile.mkstemp('.pem')
os.write(fd, (ssl_cert + '\n' + ssl_chain).encode("ascii"))
os.close(fd)
# Do validation on the certificate before installing it.
ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
cert_status, cert_status_details = check_certificate(domain, fn, ssl_private_key)
if cert_status != "OK":
if cert_status == "SELF-SIGNED":
cert_status = "This is a self-signed certificate. I can't install that."
os.unlink(fn)
if cert_status_details is not None:
cert_status += " " + cert_status_details
return cert_status
# Copy certifiate into ssl directory.
install_cert_copy_file(fn, env)
# Run post-install steps.
ret = post_install_func(env)
if raw: return ret
return "\n".join(ret)
def install_cert_copy_file(fn, env):
# Where to put it?
# Make a unique path for the certificate.
from cryptography.hazmat.primitives import hashes
from binascii import hexlify
cert = load_pem(load_cert_chain(fn)[0])
all_domains, cn = get_certificate_domains(cert)
path = "%s-%s-%s.pem" % (
safe_domain_name(cn), # common name, which should be filename safe because it is IDNA-encoded, but in case of a malformed cert make sure it's ok to use as a filename
cert.not_valid_after.date().isoformat().replace("-", ""), # expiration date
hexlify(cert.fingerprint(hashes.SHA256())).decode("ascii")[0:8], # fingerprint prefix
)
ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', path))
# Install the certificate.
os.makedirs(os.path.dirname(ssl_certificate), exist_ok=True)
shutil.move(fn, ssl_certificate)
def post_install_func(env):
ret = []
# Get the certificate to use for PRIMARY_HOSTNAME.
ssl_certificates = get_ssl_certificates(env)
cert = get_domain_ssl_files(env['PRIMARY_HOSTNAME'], ssl_certificates, env, use_main_cert=False)
if not cert:
# Ruh-row, we don't have any certificate usable
# for the primary hostname.
ret.append("there is no valid certificate for " + env['PRIMARY_HOSTNAME'])
# Symlink the best cert for PRIMARY_HOSTNAME to the system
# certificate path, which is hard-coded for various purposes, and then
# restart postfix and dovecot.
system_ssl_certificate = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_certificate.pem'))
if cert and os.readlink(system_ssl_certificate) != cert['certificate']:
# Update symlink.
ret.append("updating primary certificate")
ssl_certificate = cert['certificate']
os.unlink(system_ssl_certificate)
os.symlink(ssl_certificate, system_ssl_certificate)
# Restart postfix and dovecot so they pick up the new file.
shell('check_call', ["/usr/sbin/service", "postfix", "restart"])
shell('check_call', ["/usr/sbin/service", "dovecot", "restart"])
ret.append("mail services restarted")
# The DANE TLSA record will remain valid so long as the private key
# hasn't changed. We don't ever change the private key automatically.
# If the user does it, they must manually update DNS.
# Update the web configuration so nginx picks up the new certificate file.
from web_update import do_web_update
ret.append( do_web_update(env) )
return ret
# VALIDATION OF CERTIFICATES
def check_certificate(domain, ssl_certificate, ssl_private_key, warn_if_expiring_soon=10, rounded_time=False, just_check_domain=False):
# Check that the ssl_certificate & ssl_private_key files are good
# for the provided domain.
from cryptography.hazmat.primitives.asymmetric.rsa import RSAPrivateKey
from cryptography.x509 import Certificate
# The ssl_certificate file may contain a chain of certificates. We'll
# need to split that up before we can pass anything to openssl or
# parse them in Python. Parse it with the cryptography library.
try:
ssl_cert_chain = load_cert_chain(ssl_certificate)
cert = load_pem(ssl_cert_chain[0])
if not isinstance(cert, Certificate): raise ValueError("This is not a certificate file.")
except ValueError as e:
return ("There is a problem with the certificate file: %s" % str(e), None)
# First check that the domain name is one of the names allowed by
# the certificate.
if domain is not None:
certificate_names, cert_primary_name = get_certificate_domains(cert)
# Check that the domain appears among the acceptable names, or a wildcard
# form of the domain name (which is a stricter check than the specs but
# should work in normal cases).
wildcard_domain = re.sub("^[^\.]+", "*", domain)
if domain not in certificate_names and wildcard_domain not in certificate_names:
return ("The certificate is for the wrong domain name. It is for %s."
% ", ".join(sorted(certificate_names)), None)
# Second, check that the certificate matches the private key.
if ssl_private_key is not None:
try:
priv_key = load_pem(open(ssl_private_key, 'rb').read())
except ValueError as e:
return ("The private key file %s is not a private key file: %s" % (ssl_private_key, str(e)), None)
if not isinstance(priv_key, RSAPrivateKey):
return ("The private key file %s is not a private key file." % ssl_private_key, None)
if priv_key.public_key().public_numbers() != cert.public_key().public_numbers():
return ("The certificate does not correspond to the private key at %s." % ssl_private_key, None)
# We could also use the openssl command line tool to get the modulus
# listed in each file. The output of each command below looks like "Modulus=XXXXX".
# $ openssl rsa -inform PEM -noout -modulus -in ssl_private_key
# $ openssl x509 -in ssl_certificate -noout -modulus
# Third, check if the certificate is self-signed. Return a special flag string.
if cert.issuer == cert.subject:
return ("SELF-SIGNED", None)
# When selecting which certificate to use for non-primary domains, we check if the primary
# certificate or a www-parent-domain certificate is good for the domain. There's no need
# to run extra checks beyond this point.
if just_check_domain:
return ("OK", None)
# Check that the certificate hasn't expired. The datetimes returned by the
# certificate are 'naive' and in UTC. We need to get the current time in UTC.
import datetime
now = datetime.datetime.utcnow()
if not(cert.not_valid_before <= now <= cert.not_valid_after):
return ("The certificate has expired or is not yet valid. It is valid from %s to %s." % (cert.not_valid_before, cert.not_valid_after), None)
# Next validate that the certificate is valid. This checks whether the certificate
# is self-signed, that the chain of trust makes sense, that it is signed by a CA
# that Ubuntu has installed on this machine's list of CAs, and I think that it hasn't
# expired.
# The certificate chain has to be passed separately and is given via STDIN.
# This command returns a non-zero exit status in most cases, so trap errors.
retcode, verifyoutput = shell('check_output', [
"openssl",
"verify", "-verbose",
"-purpose", "sslserver", "-policy_check",]
+ ([] if len(ssl_cert_chain) == 1 else ["-untrusted", "/proc/self/fd/0"])
+ [ssl_certificate],
input=b"\n\n".join(ssl_cert_chain[1:]),
trap=True)
if "self signed" in verifyoutput:
# Certificate is self-signed. Probably we detected this above.
return ("SELF-SIGNED", None)
elif retcode != 0:
if "unable to get local issuer certificate" in verifyoutput:
return ("The certificate is missing an intermediate chain or the intermediate chain is incorrect or incomplete. (%s)" % verifyoutput, None)
# There is some unknown problem. Return the `openssl verify` raw output.
return ("There is a problem with the certificate.", verifyoutput.strip())
else:
# `openssl verify` returned a zero exit status so the cert is currently
# good.
# But is it expiring soon?
cert_expiration_date = cert.not_valid_after
ndays = (cert_expiration_date-now).days
if not rounded_time or ndays <= 10:
# Yikes better renew soon!
expiry_info = "The certificate expires in %d days on %s." % (ndays, cert_expiration_date.strftime("%x"))
else:
# We'll renew it with Lets Encrypt.
expiry_info = "The certificate expires on %s." % cert_expiration_date.strftime("%x")
if warn_if_expiring_soon and ndays <= warn_if_expiring_soon:
# Warn on day 10 to give 4 days for us to automatically renew the
# certificate, which occurs on day 14.
return ("The certificate is expiring soon: " + expiry_info, None)
# Return the special OK code.
return ("OK", expiry_info)
def load_cert_chain(pemfile):
# A certificate .pem file may contain a chain of certificates.
# Load the file and split them apart.
re_pem = rb"(-+BEGIN (?:.+)-+[\r\n]+(?:[A-Za-z0-9+/=]{1,64}[\r\n]+)+-+END (?:.+)-+[\r\n]+)"
with open(pemfile, "rb") as f:
pem = f.read() + b"\n" # ensure trailing newline
pemblocks = re.findall(re_pem, pem)
if len(pemblocks) == 0:
raise ValueError("File does not contain valid PEM data.")
return pemblocks
def load_pem(pem):
# Parse a "---BEGIN .... END---" PEM string and return a Python object for it
# using classes from the cryptography package.
from cryptography.x509 import load_pem_x509_certificate
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.backends import default_backend
pem_type = re.match(b"-+BEGIN (.*?)-+[\r\n]", pem)
if pem_type is None:
raise ValueError("File is not a valid PEM-formatted file.")
pem_type = pem_type.group(1)
if pem_type in (b"RSA PRIVATE KEY", b"PRIVATE KEY"):
return serialization.load_pem_private_key(pem, password=None, backend=default_backend())
if pem_type == b"CERTIFICATE":
return load_pem_x509_certificate(pem, default_backend())
raise ValueError("Unsupported PEM object type: " + pem_type.decode("ascii", "replace"))
def get_certificate_domains(cert):
from cryptography.x509 import DNSName, ExtensionNotFound, OID_COMMON_NAME, OID_SUBJECT_ALTERNATIVE_NAME
import idna
names = set()
cn = None
# The domain may be found in the Subject Common Name (CN). This comes back as an IDNA (ASCII)
# string, which is the format we store domains in - so good.
try:
cn = cert.subject.get_attributes_for_oid(OID_COMMON_NAME)[0].value
names.add(cn)
except IndexError:
# No common name? Certificate is probably generated incorrectly.
# But we'll let it error-out when it doesn't find the domain.
pass
# ... or be one of the Subject Alternative Names. The cryptography library handily IDNA-decodes
# the names for us. We must encode back to ASCII, but wildcard certificates can't pass through
# IDNA encoding/decoding so we must special-case. See https://github.com/pyca/cryptography/pull/2071.
def idna_decode_dns_name(dns_name):
if dns_name.startswith("*."):
return "*." + idna.encode(dns_name[2:]).decode('ascii')
else:
return idna.encode(dns_name).decode('ascii')
try:
sans = cert.extensions.get_extension_for_oid(OID_SUBJECT_ALTERNATIVE_NAME).value.get_values_for_type(DNSName)
for san in sans:
names.add(idna_decode_dns_name(san))
except ExtensionNotFound:
pass
return names, cn
if __name__ == "__main__":
# Provision certificates.
provision_certificates_cmdline()