#!/usr/bin/env python3
-## Call with "--help" for documentation.
+## See <https://www.ralfj.de/blog/2017/12/26/lets-encrypt.html> for documentation.
-import argparse, configparser, itertools, os, os.path, sys, subprocess, datetime
+import argparse, configparser, itertools, stat, os, os.path, sys, subprocess, datetime
## Helper functions
def readConfig(fname, defSection = 'DEFAULT'):
config.read_file(stream)
return config
-def certfile(name, suff = None):
+def certfile(name):
global config
- return os.path.join(config['dirs']['certs'], name + ".crt" + ('' if suff is None else '+'+suff) )
+ return os.path.join(config['dirs']['certs'], name + ".crt" )
def keyfile(name):
global config
return os.path.join(config['dirs']['keys'], name + ".key")
-def csrfile(name):
- global config
- return os.path.join(config['dirs']['csrs'], name + ".csr")
-
def make_backup(fname):
if os.path.exists(fname):
backupname = os.path.basename(fname) + "." + str(datetime.date.today())
def trigger_hook(hook):
global config
- exe = config['hooks'][hook]
+ exe = config['hooks'].get(hook)
if exe is not None:
subprocess.check_call([exe])
+def key_mtime(name):
+ return datetime.datetime.fromtimestamp(os.stat(keyfile(name)).st_mtime)
+
+def cert_expiry(name):
+ from certcheck import cert_expiry_date
+ return cert_expiry_date(certfile(name))
+
+## Work functions, operating on file names
+
## The interesting work
-def gencsr(name, domains):
- # This is done by a shell script
+def acme(keyfilename, certfilename, domains):
+ global config
+ accountkey = config['acme']['account-key']
+ csrfilename = certfilename + '.csr.tmp'
+ assert os.path.exists(keyfilename)
+ assert accountkey
+ # Generating the CSR is done by a shell script
exe = os.path.join(os.path.dirname(__file__), 'gencsr')
- csr = subprocess.check_output([exe, keyfile(name)] + domains)
- with open(csrfile(name), 'wb') as file:
+ csr = subprocess.check_output([exe, keyfilename] + domains)
+ assert not os.path.exists(csrfilename), "The temporary CSR file {} still exists. It seems something went wrong on a previous request. You may want to remove the file manually.".format(csrfilename)
+ with open(csrfilename, 'wb') as file:
file.write(csr)
+ try:
+ # call acme-tiny as a script
+ acme_tiny = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'acme-tiny', 'acme_tiny.py')
+ signed_crt = subprocess.check_output(["python", acme_tiny, "--quiet", "--account-key", accountkey, "--csr", csrfilename, "--acme-dir", config['acme']['challenge-dir']])
+ # save new certificate
+ make_backup(certfilename)
+ with open(certfilename, 'wb') as f:
+ f.write(signed_crt)
+ finally:
+ # clean up
+ os.remove(csrfilename)
-def acme(name, domains):
- global config
- print("Obtaining certificate {} for domains {}".format(name, ' '.join(domains)))
- gencsr(name, domains)
- # call acme-tiny as a script
- acme_tiny = os.path.join(config['acme']['acme-tiny'], 'acme_tiny.py')
- signed_crt = subprocess.check_output([acme_tiny, "--quiet", "--account-key", config['acme']['account-key'], "--csr", csrfile(name), "--acme-dir", config['acme']['challenge-dir']])
- # save new certificate
- make_backup(certfile(name))
- with open(certfile(name), 'wb') as file:
- file.write(signed_crt)
- # append DH params
- dhfile = config['DEFAULT']['dh-params']
- if dhfile is not None:
- with open(dhfile, 'rb') as file:
- dh = file.read()
- make_backup(certfile(name, 'dh'))
- with open(certfile(name, 'dh'), 'wb') as file:
- file.write(signed_crt)
- file.write(dh)
-
-def getcert(name):
+def openssl_genrsa(keyfilename):
+ with subprocess.Popen(["openssl", "genrsa", str(int(config['DEFAULT']['key-length']))], stdout=subprocess.PIPE, stderr=subprocess.PIPE) as f:
+ (stdout, stderr) = f.communicate()
+ if f.returncode:
+ sys.stderr.write(stderr)
+ raise Exception("Error while generating private key")
+ # Now we have a key, save it. This should never overwrite anything.
+ assert not os.path.exists(keyfilename)
+ with open(keyfilename, 'wb') as f:
+ f.write(stdout)
+
+## High-level functions, operating on nice key names
+def request_cert(name):
global config
if not os.path.exists(keyfile(name)):
raise Exception("No such key: {}".format(name))
domains = config['DEFAULT']['domains'].split()
- acme(name, domains)
- trigger_hook('post-cert')
+ print("Obtaining certificate '{}' for domains: {}".format(name, ' '.join(domains)))
+ acme(keyfile(name), certfile(name), domains)
+
+def generate_key(name):
+ assert not os.path.exists(certfile(name)), "Don't make create a new key for an old cert"
+ print("Generating new private key '{}'".format(name))
+ openssl_genrsa(keyfile(name))
+
+def check_staging(live, staging):
+ '''Returns 0 if nothing was done, 1 if a stage key is present but has to be kept, 2 is a stage key was unstaged.'''
+ if not os.path.exists(keyfile(staging)):
+ return 0
+
+ staging_time = datetime.timedelta(hours = int(config['timing'].get('staging-hours', 0)))
+ key_age = datetime.datetime.now() - key_mtime(staging)
+ if key_age < staging_time:
+ return 1
+ print("Unstaging '{}' to '{}'".format(staging, live))
+ # unstage the key!
+ make_backup(keyfile(live))
+ os.rename(keyfile(staging), keyfile(live))
+ make_backup(certfile(live))
+ os.rename(certfile(staging), certfile(live))
+ return 2
+
+def auto_renewal(live, staging):
+ '''Returns 0 if nothing was done, 1 if only certs were changed, 2 if certs and keys were changed.'''
+ max_key_age = datetime.timedelta(days = int(config['timing']['max-key-age-days']))
+ renew_cert_time = datetime.timedelta(days = int(config['timing']['renew-cert-before-expiry-days']))
+
+ # determine what to do
+ now = datetime.datetime.now()
+ key_age = now - key_mtime(live)
+ cert_validity = cert_expiry(live) - now
+ need_new_key = key_age >= max_key_age
+ need_new_cert = cert_validity <= renew_cert_time
+ if need_new_cert and key_age + renew_cert_time >= max_key_age:
+ # We are about to request a new certificate, and within <renew_cert_time>, we need a new key: Get the new key now
+ need_new_key = True
+
+ # Do it
+ if need_new_key:
+ generate_key(staging)
+ request_cert(staging)
+ check_staging(live, staging) # we may want to immediately enable the new key & cert
+ return 2
+ elif need_new_cert:
+ request_cert(live)
+ return 1
+ else:
+ return 0
## Main
if __name__ == "__main__":
parser.add_argument("-c", "--config",
dest="config",
help="The configuration file")
- parser.add_argument
+ parser.add_argument("-k", "--hooks",
+ dest="hooks", action="store_true",
+ help="Trigger hooks.")
parser.add_argument("action", metavar='ACTION', nargs=1,
- help="The action to perform. Possible values: renew, cron")
+ help="The action to perform. Possible values: init, renew, cron")
args = parser.parse_args()
- # read config
+ # read config, sanity check
if not os.path.isfile(args.config):
raise Exception("The config file does not exist: "+args.config)
global config
config = readConfig(args.config)
+ live = config['files']['live']
+ staging = config['files']['staging']
if args.action[0] == 'renew':
- getcert(config['files']['live'])
- # We may also have to renew the staging
- staging = config['files']['staging']
- if staging is not None and os.path.exists(keyfile(staging)):
- getcert(staging)
+ request_cert(live)
+ if os.path.exists(keyfile(staging)) and os.path.exists(certfile(staging)):
+ request_cert(staging)
+ # trigger the "new cert" hook
+ if args.hooks:
+ trigger_hook('post-certchange')
+ elif args.action[0] == 'cron':
+ # First, check if we need to unstage a staging key
+ unstaged = check_staging(live, staging)
+ if unstaged >= 1:
+ # A staging key is present, do *not* check for renewal
+ if unstaged >= 2 and args.hooks:
+ # trigger all the hooks
+ trigger_hook('post-certchange')
+ trigger_hook('post-keychange')
+ else:
+ # Check if we need to renew anything
+ renewed = auto_renewal(live, staging)
+ if args.hooks:
+ if renewed >= 1:
+ trigger_hook('post-certchange')
+ if renewed >= 2:
+ trigger_hook('post-keychange')
+ elif args.action[0] == 'init':
+ # create directories with appropriate permissions
+ try:
+ os.makedirs(config['dirs']['certs'], mode = 0o755, exist_ok = True)
+ os.makedirs(config['dirs']['keys'], mode = 0o710, exist_ok = True)
+ os.makedirs(config['dirs']['backups'], mode = 0o700, exist_ok = True)
+ except OSError:
+ pass
+ # if necessary, generate ACME account key
+ accountkey = config['acme']['account-key']
+ if not os.path.exists(accountkey):
+ print("Generating new ACME key")
+ openssl_genrsa(accountkey)
+ # if necessary, generate key + certificate
+ live = config['files']['live']
+ if not os.path.exists(keyfile(live)):
+ generate_key(live)
+ if not os.path.exists(certfile(live)):
+ request_cert(live)
+ if args.hooks:
+ trigger_hook('post-certchange')
+ trigger_hook('post-keychange')
else:
raise Exception("Unknown action {}".format(args.action))
projects / lets-encrypt-tiny.git / blobdiff