From ebef5c71b3669d4fcca001d91f84b76266786618 Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sun, 13 Dec 2015 15:04:10 +0100 Subject: [PATCH 1/1] add the cron job --- letsencrypt-tiny | 154 +++++++++++++++++++++++++++++------ letsencrypt-tiny.conf.sample | 15 +++- 2 files changed, 143 insertions(+), 26 deletions(-) diff --git a/letsencrypt-tiny b/letsencrypt-tiny index 0d8c985..eb9d171 100755 --- a/letsencrypt-tiny +++ b/letsencrypt-tiny @@ -1,7 +1,7 @@ #!/usr/bin/env python3 ## Call with "--help" 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'): @@ -30,7 +30,7 @@ def make_backup(fname): while True: backupfile = os.path.join(config['dirs']['backups'], backupname + "." + str(i)) if not os.path.exists(backupfile): - os.rename(fname, backupfile) + os.rename(src = fname, dst = backupfile) break elif i >= 100: print("Somehow it's really hard to find a name for the backup file...") @@ -43,42 +43,108 @@ def trigger_hook(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)) + ## The interesting work -def gencsr(name, domains): - # This is done by a shell script +def acme(name, domains): + global config + # 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: file.write(csr) - -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) + with open(certfile(name), 'wb') as f: + f.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) + with open(dhfile, 'rb') as f: + dh = f.read() + with open(certfile(name, 'dh'), 'wb') as f: + f.write(signed_crt) + f.write(dh) -def getcert(name): +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() + print("Obtaining certificate '{}' for domains {}".format(name, ' '.join(domains))) acme(name, domains) - trigger_hook('post-cert') + +def generate_key(name): + print("Generating new private key '{}'".format(name)) + 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 + make_backup(keyfile(name)) + with open(keyfile(name), 'wb') as f: + f.write(stdout) + +def check_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.''' + live = config['files']['live'] + staging = config['files']['staging'] + if staging is None or not os.path.exists(keyfile(staging)): + return 0 + staging_time = datetime.timedelta(hours = int(config['timing']['staging-hours'])) + 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(src = keyfile(staging), dst = keyfile(live)) + make_backup(certfile(live)) + os.rename(src = certfile(staging), dst = certfile(live)) + try: + os.rename(src = certfile(staging, 'dh'), dst = certfile(live, 'dh')) + except FileNotFoundError: + pass + return 2 + +def auto_renewal(): + '''Returns 0 if nothing was done, 1 if only certs were changed, 2 if certs and keys were changed.''' + live = config['files']['live'] + staging = config['files']['staging'] + + 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 , we need a new key: Get the new key now + need_new_key = True + + # Do it + if need_new_key: + new_key_name = (live if staging is None else staging) + generate_key(new_key_name) + request_cert(new_key_name) + return 2 + elif need_new_cert: + request_cert(live) + return 1 + else: + return 0 ## Main if __name__ == "__main__": @@ -87,9 +153,11 @@ 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 @@ -99,10 +167,48 @@ if __name__ == "__main__": config = readConfig(args.config) if args.action[0] == 'renew': - getcert(config['files']['live']) - # We may also have to renew the staging + live = config['files']['live'] staging = config['files']['staging'] + + request_cert(live) if staging is not None and os.path.exists(keyfile(staging)): - getcert(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() + if unstaged >= 1: + # A staging eky 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() + 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']['csrs'], mode = 0o755, exist_ok = True) + os.makedirs(config['dirs']['backups'], mode = 0o700, exist_ok = True) + except OSError: + pass + # if necessary, generate key + certificate + live = config['files']['live'] + if not os.path.exists(keyfile(live)): + generate_key(live) + request_cert(live) + if args.hooks: + trigger_hook('post-certchange') + trigger_hook('post-keychange') else: raise Exception("Unknown action {}".format(args.action)) diff --git a/letsencrypt-tiny.conf.sample b/letsencrypt-tiny.conf.sample index d2535e5..f195128 100644 --- a/letsencrypt-tiny.conf.sample +++ b/letsencrypt-tiny.conf.sample @@ -5,16 +5,27 @@ domains = example.org example.com +# The length of secret RSA keys +key-length = 4096 + # File containing the DH parameters, as generated by openssl (optional) dh-params = /etc/ssl/dh2048.pem +[timing] +# After how many days should the private key be re-generated? +max-key-age-days = 180 +# How many hours should a new private key be left in staging? (0 for no staging) +staging-hours = 25 +# How many days before a certificate expires, should it be renewed? +renew-cert-before-expiry-days = 15 + [hooks] # Called after a new certificate has been obtained. # Example usage: Reloading services. -post-cert = /home/user/letsencrypt/cert-hook +post-certchange = /home/user/letsencrypt/cert-hook # Called after a new certificate has been obtained, *if* there also were changes in the private keys # Example usage: Updating TLSA records (with the selector being SubjectPublicKeyInfo) in the zone -post-key = /home/user/letsencrypt/key-hook +post-keychange = /home/user/letsencrypt/key-hook # Parameters for acme-tiny [acme] -- 2.30.2