Files
cloudron-box/src/cert/acme1.js
2018-09-10 20:48:47 -07:00

482 lines
20 KiB
JavaScript

'use strict';
var assert = require('assert'),
async = require('async'),
crypto = require('crypto'),
debug = require('debug')('box:cert/acme1'),
execSync = require('safetydance').child_process.execSync,
fs = require('fs'),
parseLinks = require('parse-links'),
path = require('path'),
paths = require('../paths.js'),
safe = require('safetydance'),
superagent = require('superagent'),
util = require('util'),
_ = require('underscore');
var CA_PROD = 'https://acme-v01.api.letsencrypt.org',
CA_STAGING = 'https://acme-staging.api.letsencrypt.org',
LE_AGREEMENT = 'https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf';
exports = module.exports = {
getCertificate: getCertificate,
// testing
_name: 'acme'
};
function Acme1Error(reason, errorOrMessage) {
assert.strictEqual(typeof reason, 'string');
assert(errorOrMessage instanceof Error || typeof errorOrMessage === 'string' || typeof errorOrMessage === 'undefined');
Error.call(this);
Error.captureStackTrace(this, this.constructor);
this.name = this.constructor.name;
this.reason = reason;
if (typeof errorOrMessage === 'undefined') {
this.message = reason;
} else if (typeof errorOrMessage === 'string') {
this.message = errorOrMessage;
} else {
this.message = 'Internal error';
this.nestedError = errorOrMessage;
}
}
util.inherits(Acme1Error, Error);
Acme1Error.INTERNAL_ERROR = 'Internal Error';
Acme1Error.EXTERNAL_ERROR = 'External Error';
Acme1Error.ALREADY_EXISTS = 'Already Exists';
Acme1Error.NOT_COMPLETED = 'Not Completed';
Acme1Error.FORBIDDEN = 'Forbidden';
// http://jose.readthedocs.org/en/latest/
// https://www.ietf.org/proceedings/92/slides/slides-92-acme-1.pdf
// https://community.letsencrypt.org/t/list-of-client-implementations/2103
function Acme1(options) {
assert.strictEqual(typeof options, 'object');
this.caOrigin = options.prod ? CA_PROD : CA_STAGING;
this.accountKeyPem = null; // Buffer
this.email = options.email;
}
Acme1.prototype.getNonce = function (callback) {
superagent.get(this.caOrigin + '/directory').timeout(30 * 1000).end(function (error, response) {
if (error && !error.response) return callback(error);
if (response.statusCode !== 200) return callback(new Error('Invalid response code when fetching nonce : ' + response.statusCode));
return callback(null, response.headers['Replay-Nonce'.toLowerCase()]);
});
};
// urlsafe base64 encoding (jose)
function urlBase64Encode(string) {
return string.replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
}
function b64(str) {
var buf = util.isBuffer(str) ? str : new Buffer(str);
return urlBase64Encode(buf.toString('base64'));
}
function getModulus(pem) {
assert(util.isBuffer(pem));
var stdout = execSync('openssl rsa -modulus -noout', { input: pem, encoding: 'utf8' });
if (!stdout) return null;
var match = stdout.match(/Modulus=([0-9a-fA-F]+)$/m);
if (!match) return null;
return Buffer.from(match[1], 'hex');
}
Acme1.prototype.sendSignedRequest = function (url, payload, callback) {
assert.strictEqual(typeof url, 'string');
assert.strictEqual(typeof payload, 'string');
assert.strictEqual(typeof callback, 'function');
assert(util.isBuffer(this.accountKeyPem));
var that = this;
var header = {
alg: 'RS256',
jwk: {
e: b64(Buffer.from([0x01, 0x00, 0x01])), // exponent - 65537
kty: 'RSA',
n: b64(getModulus(this.accountKeyPem))
}
};
var payload64 = b64(payload);
this.getNonce(function (error, nonce) {
if (error) return callback(error);
debug('sendSignedRequest: using nonce %s for url %s', nonce, url);
var protected64 = b64(JSON.stringify(_.extend({ }, header, { nonce: nonce })));
var signer = crypto.createSign('RSA-SHA256');
signer.update(protected64 + '.' + payload64, 'utf8');
var signature64 = urlBase64Encode(signer.sign(that.accountKeyPem, 'base64'));
var data = {
header: header,
protected: protected64,
payload: payload64,
signature: signature64
};
superagent.post(url).set('Content-Type', 'application/x-www-form-urlencoded').send(JSON.stringify(data)).timeout(30 * 1000).end(function (error, res) {
if (error && !error.response) return callback(error); // network errors
callback(null, res);
});
});
};
Acme1.prototype.updateContact = function (registrationUri, callback) {
assert.strictEqual(typeof registrationUri, 'string');
assert.strictEqual(typeof callback, 'function');
debug('updateContact: %s %s', registrationUri, this.email);
// https://github.com/ietf-wg-acme/acme/issues/30
var payload = {
resource: 'reg',
contact: [ 'mailto:' + this.email ],
agreement: LE_AGREEMENT
};
var that = this;
this.sendSignedRequest(registrationUri, JSON.stringify(payload), function (error, result) {
if (error) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when registering user: ' + error.message));
if (result.statusCode !== 202) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to update contact. Expecting 202, got %s %s', result.statusCode, result.text)));
debug('updateContact: contact of user updated to %s', that.email);
callback();
});
};
Acme1.prototype.registerUser = function (callback) {
assert.strictEqual(typeof callback, 'function');
var payload = {
resource: 'new-reg',
contact: [ 'mailto:' + this.email ],
agreement: LE_AGREEMENT
};
debug('registerUser: %s', this.email);
var that = this;
this.sendSignedRequest(this.caOrigin + '/acme/new-reg', JSON.stringify(payload), function (error, result) {
if (error) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when registering user: ' + error.message));
if (result.statusCode === 409) return that.updateContact(result.headers.location, callback); // already exists
if (result.statusCode !== 201) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to register user. Expecting 201, got %s %s', result.statusCode, result.text)));
debug('registerUser: registered user %s', that.email);
callback(null);
});
};
Acme1.prototype.registerDomain = function (domain, callback) {
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof callback, 'function');
var payload = {
resource: 'new-authz',
identifier: {
type: 'dns',
value: domain
}
};
debug('registerDomain: %s', domain);
this.sendSignedRequest(this.caOrigin + '/acme/new-authz', JSON.stringify(payload), function (error, result) {
if (error) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when registering domain: ' + error.message));
if (result.statusCode === 403) return callback(new Acme1Error(Acme1Error.FORBIDDEN, result.body.detail));
if (result.statusCode !== 201) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to register user. Expecting 201, got %s %s', result.statusCode, result.text)));
debug('registerDomain: registered %s', domain);
callback(null, result.body);
});
};
Acme1.prototype.prepareHttpChallenge = function (challenge, callback) {
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('prepareHttpChallenge: preparing for challenge %j', challenge);
var token = challenge.token;
assert(util.isBuffer(this.accountKeyPem));
var jwk = {
e: b64(Buffer.from([0x01, 0x00, 0x01])), // Exponent - 65537
kty: 'RSA',
n: b64(getModulus(this.accountKeyPem))
};
var shasum = crypto.createHash('sha256');
shasum.update(JSON.stringify(jwk));
var thumbprint = urlBase64Encode(shasum.digest('base64'));
var keyAuthorization = token + '.' + thumbprint;
debug('prepareHttpChallenge: writing %s to %s', keyAuthorization, path.join(paths.ACME_CHALLENGES_DIR, token));
fs.writeFile(path.join(paths.ACME_CHALLENGES_DIR, token), token + '.' + thumbprint, function (error) {
if (error) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, error));
callback();
});
};
Acme1.prototype.notifyChallengeReady = function (challenge, callback) {
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('notifyChallengeReady: %s was met', challenge.uri);
var keyAuthorization = fs.readFileSync(path.join(paths.ACME_CHALLENGES_DIR, challenge.token), 'utf8');
var payload = {
resource: 'challenge',
keyAuthorization: keyAuthorization
};
this.sendSignedRequest(challenge.uri, JSON.stringify(payload), function (error, result) {
if (error) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when notifying challenge: ' + error.message));
if (result.statusCode !== 202) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to notify challenge. Expecting 202, got %s %s', result.statusCode, result.text)));
callback();
});
};
Acme1.prototype.waitForChallenge = function (challenge, callback) {
assert.strictEqual(typeof challenge, 'object');
assert.strictEqual(typeof callback, 'function');
debug('waitingForChallenge: %j', challenge);
async.retry({ times: 10, interval: 5000 }, function (retryCallback) {
debug('waitingForChallenge: getting status');
superagent.get(challenge.uri).timeout(30 * 1000).end(function (error, result) {
if (error && !error.response) {
debug('waitForChallenge: network error getting uri %s', challenge.uri);
return retryCallback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, error.message)); // network error
}
if (result.statusCode !== 202) {
debug('waitForChallenge: invalid response code getting uri %s', result.statusCode);
return retryCallback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Bad response code:' + result.statusCode));
}
debug('waitForChallenge: status is "%s %j', result.body.status, result.body);
if (result.body.status === 'pending') return retryCallback(new Acme1Error(Acme1Error.NOT_COMPLETED));
else if (result.body.status === 'valid') return retryCallback();
else return retryCallback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Unexpected status: ' + result.body.status));
});
}, function retryFinished(error) {
// async.retry will pass 'undefined' as second arg making it unusable with async.waterfall()
callback(error);
});
};
// https://community.letsencrypt.org/t/public-beta-rate-limits/4772 for rate limits
Acme1.prototype.signCertificate = function (domain, csrDer, callback) {
assert.strictEqual(typeof domain, 'string');
assert(util.isBuffer(csrDer));
assert.strictEqual(typeof callback, 'function');
var outdir = paths.APP_CERTS_DIR;
var payload = {
resource: 'new-cert',
csr: b64(csrDer)
};
debug('signCertificate: sending new-cert request');
this.sendSignedRequest(this.caOrigin + '/acme/new-cert', JSON.stringify(payload), function (error, result) {
if (error) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when signing certificate: ' + error.message));
// 429 means we reached the cert limit for this domain
if (result.statusCode !== 201) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to sign certificate. Expecting 201, got %s %s', result.statusCode, result.text)));
var certUrl = result.headers.location;
if (!certUrl) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Missing location in downloadCertificate'));
safe.fs.writeFileSync(path.join(outdir, domain + '.url'), certUrl, 'utf8'); // maybe use for renewal
return callback(null, result.headers.location);
});
};
Acme1.prototype.createKeyAndCsr = function (domain, callback) {
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof callback, 'function');
var outdir = paths.APP_CERTS_DIR;
var csrFile = path.join(outdir, domain + '.csr');
var privateKeyFile = path.join(outdir, domain + '.key');
if (safe.fs.existsSync(privateKeyFile)) {
// in some old releases, csr file was corrupt. so always regenerate it
debug('createKeyAndCsr: reuse the key for renewal at %s', privateKeyFile);
} else {
var key = execSync('openssl genrsa 4096');
if (!key) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
if (!safe.fs.writeFileSync(privateKeyFile, key)) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
debug('createKeyAndCsr: key file saved at %s', privateKeyFile);
}
var csrDer = execSync(util.format('openssl req -new -key %s -outform DER -subj /CN=%s', privateKeyFile, domain));
if (!csrDer) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
if (!safe.fs.writeFileSync(csrFile, csrDer)) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error)); // bookkeeping
debug('createKeyAndCsr: csr file (DER) saved at %s', csrFile);
callback(null, csrDer);
};
// TODO: download the chain in a loop following 'up' header
Acme1.prototype.downloadChain = function (linkHeader, callback) {
if (!linkHeader) return new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Empty link header when downloading certificate chain');
debug('downloadChain: linkHeader %s', linkHeader);
var linkInfo = parseLinks(linkHeader);
if (!linkInfo || !linkInfo.up) return new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Failed to parse link header when downloading certificate chain');
var intermediateCertUrl = linkInfo.up.startsWith('https://') ? linkInfo.up : (this.caOrigin + linkInfo.up);
debug('downloadChain: downloading from %s', intermediateCertUrl);
superagent.get(intermediateCertUrl).buffer().parse(function (res, done) {
var data = [ ];
res.on('data', function(chunk) { data.push(chunk); });
res.on('end', function () { res.text = Buffer.concat(data); done(); });
}).timeout(30 * 1000).end(function (error, result) {
if (error && !error.response) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when downloading certificate'));
if (result.statusCode !== 200) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to get cert. Expecting 200, got %s %s', result.statusCode, result.text)));
var chainDer = result.text;
var chainPem = execSync('openssl x509 -inform DER -outform PEM', { input: chainDer }); // this is really just base64 encoding with header
if (!chainPem) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
callback(null, chainPem);
});
};
Acme1.prototype.downloadCertificate = function (domain, certUrl, callback) {
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof certUrl, 'string');
assert.strictEqual(typeof callback, 'function');
var outdir = paths.APP_CERTS_DIR;
var that = this;
superagent.get(certUrl).buffer().parse(function (res, done) {
var data = [ ];
res.on('data', function(chunk) { data.push(chunk); });
res.on('end', function () { res.text = Buffer.concat(data); done(); });
}).timeout(30 * 1000).end(function (error, result) {
if (error && !error.response) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'Network error when downloading certificate'));
if (result.statusCode === 202) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, 'Retry not implemented yet'));
if (result.statusCode !== 200) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, util.format('Failed to get cert. Expecting 200, got %s %s', result.statusCode, result.text)));
var certificateDer = result.text;
safe.fs.writeFileSync(path.join(outdir, domain + '.der'), certificateDer);
debug('downloadCertificate: cert der file for %s saved', domain);
var certificatePem = execSync('openssl x509 -inform DER -outform PEM', { input: certificateDer }); // this is really just base64 encoding with header
if (!certificatePem) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
that.downloadChain(result.header['link'], function (error, chainPem) {
if (error) return callback(error);
var certificateFile = path.join(outdir, domain + '.cert');
var fullChainPem = Buffer.concat([certificatePem, chainPem]);
if (!safe.fs.writeFileSync(certificateFile, fullChainPem)) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
debug('downloadCertificate: cert file for %s saved at %s', domain, certificateFile);
callback();
});
});
};
Acme1.prototype.acmeFlow = function (domain, callback) {
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof callback, 'function');
if (!fs.existsSync(paths.ACME_ACCOUNT_KEY_FILE)) {
debug('getCertificate: generating acme account key on first run');
this.accountKeyPem = safe.child_process.execSync('openssl genrsa 4096');
if (!this.accountKeyPem) return callback(new Acme1Error(Acme1Error.INTERNAL_ERROR, safe.error));
safe.fs.writeFileSync(paths.ACME_ACCOUNT_KEY_FILE, this.accountKeyPem);
} else {
debug('getCertificate: using existing acme account key');
this.accountKeyPem = fs.readFileSync(paths.ACME_ACCOUNT_KEY_FILE);
}
var that = this;
this.registerUser(function (error) {
if (error) return callback(error);
that.registerDomain(domain, function (error, result) {
if (error) return callback(error);
debug('acmeFlow: challenges: %j', result);
var httpChallenges = result.challenges.filter(function(x) { return x.type === 'http-01'; });
if (httpChallenges.length === 0) return callback(new Acme1Error(Acme1Error.EXTERNAL_ERROR, 'no http challenges'));
var challenge = httpChallenges[0];
async.waterfall([
that.prepareHttpChallenge.bind(that, challenge),
that.notifyChallengeReady.bind(that, challenge),
that.waitForChallenge.bind(that, challenge),
that.createKeyAndCsr.bind(that, domain),
that.signCertificate.bind(that, domain),
that.downloadCertificate.bind(that, domain)
], callback);
});
});
};
Acme1.prototype.getCertificate = function (hostname, domain, callback) {
assert.strictEqual(typeof hostname, 'string');
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof callback, 'function');
debug('getCertificate: start acme flow for %s from %s', hostname, this.caOrigin);
this.acmeFlow(hostname, function (error) {
if (error) return callback(error);
var outdir = paths.APP_CERTS_DIR;
callback(null, path.join(outdir, hostname + '.cert'), path.join(outdir, hostname + '.key'));
});
};
function getCertificate(hostname, domain, options, callback) {
assert.strictEqual(typeof hostname, 'string');
assert.strictEqual(typeof domain, 'string');
assert.strictEqual(typeof options, 'object');
assert.strictEqual(typeof callback, 'function');
var acme = new Acme1(options || { });
acme.getCertificate(hostname, domain, callback);
}