diff --git a/helper-scripts/generate_caa_record.py b/helper-scripts/generate_caa_record.py new file mode 100755 index 000000000..5ccfbd030 --- /dev/null +++ b/helper-scripts/generate_caa_record.py @@ -0,0 +1,122 @@ +#!/usr/bin/env python3 +# Based on github.com/diafygi/acme-tiny, original copyright: +# Copyright Daniel Roesler, under MIT license, see LICENSE at github.com/diafygi/acme-tiny +import argparse, subprocess, json, os, sys, base64, binascii, time, hashlib, re, copy, textwrap, logging +try: + from urllib.request import urlopen, Request # Python 3 +except ImportError: # pragma: no cover + from urllib2 import urlopen, Request # Python 2 + +DEFAULT_DIRECTORY_URL = "https://acme-v02.api.letsencrypt.org/directory" + +LOGGER = logging.getLogger(__name__) +LOGGER.addHandler(logging.StreamHandler()) +LOGGER.setLevel(logging.INFO) + +def get_id(account_key, log=LOGGER, directory_url=DEFAULT_DIRECTORY_URL, contact=None): + directory, acct_headers, alg, jwk = None, None, None, None # global variables + + # helper functions - base64 encode for jose spec + def _b64(b): + return base64.urlsafe_b64encode(b).decode('utf8').replace("=", "") + + # helper function - run external commands + def _cmd(cmd_list, stdin=None, cmd_input=None, err_msg="Command Line Error"): + proc = subprocess.Popen(cmd_list, stdin=stdin, stdout=subprocess.PIPE, stderr=subprocess.PIPE) + out, err = proc.communicate(cmd_input) + if proc.returncode != 0: + raise IOError("{0}\n{1}".format(err_msg, err)) + return out + + # helper function - make request and automatically parse json response + def _do_request(url, data=None, err_msg="Error", depth=0): + try: + resp = urlopen(Request(url, data=data, headers={"Content-Type": "application/jose+json", "User-Agent": "acme-tiny"})) + resp_data, code, headers = resp.read().decode("utf8"), resp.getcode(), resp.headers + except IOError as e: + resp_data = e.read().decode("utf8") if hasattr(e, "read") else str(e) + code, headers = getattr(e, "code", None), {} + try: + resp_data = json.loads(resp_data) # try to parse json results + except ValueError: + pass # ignore json parsing errors + if depth < 100 and code == 400 and resp_data['type'] == "urn:ietf:params:acme:error:badNonce": + raise IndexError(resp_data) # allow 100 retrys for bad nonces + if code not in [200, 201, 204]: + raise ValueError("{0}:\nUrl: {1}\nData: {2}\nResponse Code: {3}\nResponse: {4}".format(err_msg, url, data, code, resp_data)) + return resp_data, code, headers + + # helper function - make signed requests + def _send_signed_request(url, payload, err_msg, depth=0): + payload64 = "" if payload is None else _b64(json.dumps(payload).encode('utf8')) + new_nonce = _do_request(directory['newNonce'])[2]['Replay-Nonce'] + protected = {"url": url, "alg": alg, "nonce": new_nonce} + protected.update({"jwk": jwk} if acct_headers is None else {"kid": acct_headers['Location']}) + protected64 = _b64(json.dumps(protected).encode('utf8')) + protected_input = "{0}.{1}".format(protected64, payload64).encode('utf8') + out = _cmd(["openssl", "dgst", "-sha256", "-sign", account_key], stdin=subprocess.PIPE, cmd_input=protected_input, err_msg="OpenSSL Error") + data = json.dumps({"protected": protected64, "payload": payload64, "signature": _b64(out)}) + try: + return _do_request(url, data=data.encode('utf8'), err_msg=err_msg, depth=depth) + except IndexError: # retry bad nonces (they raise IndexError) + return _send_signed_request(url, payload, err_msg, depth=(depth + 1)) + + # helper function - poll until complete + def _poll_until_not(url, pending_statuses, err_msg): + result, t0 = None, time.time() + while result is None or result['status'] in pending_statuses: + assert (time.time() - t0 < 3600), "Polling timeout" # 1 hour timeout + time.sleep(0 if result is None else 2) + result, _, _ = _send_signed_request(url, None, err_msg) + return result + + # parse account key to get public key + log.info("Parsing account key...") + out = _cmd(["openssl", "rsa", "-in", account_key, "-noout", "-text"], err_msg="OpenSSL Error") + pub_pattern = r"modulus:[\s]+?00:([a-f0-9\:\s]+?)\npublicExponent: ([0-9]+)" + pub_hex, pub_exp = re.search(pub_pattern, out.decode('utf8'), re.MULTILINE|re.DOTALL).groups() + pub_exp = "{0:x}".format(int(pub_exp)) + pub_exp = "0{0}".format(pub_exp) if len(pub_exp) % 2 else pub_exp + alg, jwk = "RS256", { + "e": _b64(binascii.unhexlify(pub_exp.encode("utf-8"))), + "kty": "RSA", + "n": _b64(binascii.unhexlify(re.sub(r"(\s|:)", "", pub_hex).encode("utf-8"))), + } + accountkey_json = json.dumps(jwk, sort_keys=True, separators=(',', ':')) + thumbprint = _b64(hashlib.sha256(accountkey_json.encode('utf8')).digest()) + + # get the ACME directory of urls + log.info("Getting directory...") + directory, _, _ = _do_request(directory_url, err_msg="Error getting directory") + log.info("Directory found!") + + # create account and get the global key identifier + log.info("Registering account...") + reg_payload = {"termsOfServiceAgreed": True} if contact is None else {"termsOfServiceAgreed": True, "contact": contact} + account, code, acct_headers = _send_signed_request(directory['newAccount'], reg_payload, "Error registering") + log.info("Registered!" if code == 201 else "Already registered!") + + return acct_headers['Location'] + +def main(argv=None): + parser = argparse.ArgumentParser( + formatter_class=argparse.RawDescriptionHelpFormatter, + description=textwrap.dedent("""\ + Generate a CAA record for Mailcow. + + Example Usage: python mailcow_gencaa.py --account-key data/assets/ssl/acme/account.pem + """) + ) + parser.add_argument("--account-key", required=True, help="path to your Let's Encrypt account private key") + parser.add_argument("--quiet", action="store_const", const=logging.ERROR, help="suppress output except for errors") + parser.add_argument("--directory-url", default=DEFAULT_DIRECTORY_URL, help="certificate authority directory url, default is Let's Encrypt") + parser.add_argument("--contact", metavar="CONTACT", default=None, nargs="*", help="Contact details (e.g. mailto:aaa@bbb.com) for your account-key") + + args = parser.parse_args(argv) + LOGGER.setLevel(args.quiet or LOGGER.level) + id = get_id(args.account_key, log=LOGGER, directory_url=args.directory_url, contact=args.contact) + print("Use this as your CAA record:") + print('issue 128 "letsencrypt.org;accounturi={}"'.format(id)) + +if __name__ == "__main__": # pragma: no cover + main(sys.argv[1:])