3 * StatusNet - the distributed open-source microblogging tool
4 * Copyright (C) 2010, StatusNet, Inc.
6 * A sample module to show best practices for StatusNet plugins
10 * This program is free software: you can redistribute it and/or modify
11 * it under the terms of the GNU Affero General Public License as published by
12 * the Free Software Foundation, either version 3 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Affero General Public License for more details.
20 * You should have received a copy of the GNU Affero General Public License
21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 * @author James Walker <james@status.net>
25 * @copyright 2010 StatusNet, Inc.
26 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
27 * @link http://status.net/
30 if (!defined('STATUSNET')) {
34 require_once 'Crypt/RSA.php';
36 class Magicsig extends Managed_DataObject
38 const PUBLICKEYREL = 'magic-public-key';
39 const DIASPORA_PUBLICKEYREL = 'diaspora-public-key';
41 public $__table = 'magicsig';
44 * Key to user.id/profile.id for the local user whose key we're storing.
51 * Flattened string representation of the key pair; callers should
52 * usually use $this->publicKey and $this->privateKey directly,
53 * which hold live Crypt_RSA key objects.
60 * Crypto algorithm used for this key; currently only RSA-SHA256 is supported.
67 * Public RSA key; gets serialized in/out via $this->keypair string.
74 * PrivateRSA key; gets serialized in/out via $this->keypair string.
80 public function __construct($alg = 'RSA-SHA256')
86 * Fetch a Magicsig object from the cache or database on a field match.
92 static function getKV($k, $v=null)
94 $obj = parent::getKV($k, $v);
95 if ($obj instanceof Magicsig) {
96 $obj->importKeys(); // Loads Crypt_RSA objects etc.
98 // Throw out a big fat warning for keys of less than 1024 bits. (
99 // The only case these show up in would be imported or
100 // legacy very-old-StatusNet generated keypairs.
101 if (strlen($obj->publicKey->modulus->toBits()) < 1024) {
102 common_log(LOG_WARNING, sprintf('Salmon key with <1024 bits (%d) belongs to profile with id==%d',
103 strlen($obj->publicKey->modulus->toBits()),
111 public static function schemaDef()
115 'user_id' => array('type' => 'int', 'not null' => true, 'description' => 'user id'),
116 'keypair' => array('type' => 'text', 'description' => 'keypair text representation'),
117 'alg' => array('type' => 'varchar', 'length' => 64, 'description' => 'algorithm'),
119 'primary key' => array('user_id'),
120 'foreign keys' => array(
121 'magicsig_user_id_fkey' => array('profile', array('user_id' => 'id')),
127 * Save this keypair into the database.
129 * Overloads default insert behavior to encode the live key objects
130 * as a flat string for storage.
136 $this->keypair = $this->toString(true);
138 return parent::insert();
142 * Generate a new keypair for a local user and store in the database.
144 * Warning: this can be very slow on systems without the GMP module.
145 * Runtimes of 20-30 seconds are not unheard-of.
147 * @param User $user the local user (since we don't have remote private keys)
149 public static function generate(User $user, $bits=1024, $alg='RSA-SHA256')
151 $magicsig = new Magicsig($alg);
152 $magicsig->user_id = $user->id;
154 $rsa = new Crypt_RSA();
156 $keypair = $rsa->createKey($bits);
158 $magicsig->privateKey = new Crypt_RSA();
159 $magicsig->privateKey->loadKey($keypair['privatekey']);
161 $magicsig->publicKey = new Crypt_RSA();
162 $magicsig->publicKey->loadKey($keypair['publickey']);
164 $magicsig->insert(); // will do $this->keypair = $this->toString(true);
165 $magicsig->importKeys(); // seems it's necessary to re-read keys from text keypair
171 * Encode the keypair or public key as a string.
173 * @param boolean $full_pair set to true to include the private key.
176 public function toString($full_pair=false)
178 $mod = Magicsig::base64_url_encode($this->publicKey->modulus->toBytes());
179 $exp = Magicsig::base64_url_encode($this->publicKey->exponent->toBytes());
181 if ($full_pair && $this->privateKey instanceof Crypt_RSA && $this->privateKey->exponent->toBytes()) {
182 $private_exp = '.' . Magicsig::base64_url_encode($this->privateKey->exponent->toBytes());
185 return 'RSA.' . $mod . '.' . $exp . $private_exp;
188 public function exportPublicKey($format=CRYPT_RSA_PUBLIC_FORMAT_PKCS1)
190 $this->publicKey->setPublicKey();
191 return $this->publicKey->getPublicKey($format);
195 * importKeys will load the object's keypair string, which initiates
196 * loadKey() and configures Crypt_RSA objects.
198 * @param string $keypair optional, otherwise the object's "keypair" property will be used
200 public function importKeys($keypair=null)
202 $this->keypair = $keypair===null ? $this->keypair : preg_replace('/\s+/', '', $keypair);
205 if (!preg_match('/RSA\.([^\.]+)\.([^\.]+)(\.([^\.]+))?/', $this->keypair, $matches)) {
206 common_debug('Magicsig error: RSA key not found in provided string.');
207 throw new ServerException('RSA key not found in keypair string.');
212 if (!empty($matches[4])) {
213 $private_exp = $matches[4];
215 $private_exp = false;
218 $this->loadKey($mod, $exp, 'public');
220 $this->loadKey($mod, $private_exp, 'private');
225 * Fill out $this->privateKey or $this->publicKey with a Crypt_RSA object
226 * representing the give key (as mod/exponent pair).
228 * @param string $mod base64-encoded
229 * @param string $exp base64-encoded exponent
230 * @param string $type one of 'public' or 'private'
232 public function loadKey($mod, $exp, $type = 'public')
234 $rsa = new Crypt_RSA();
235 $rsa->setSignatureMode(CRYPT_RSA_SIGNATURE_PKCS1);
236 $rsa->setHash($this->getHash());
237 $rsa->modulus = new Math_BigInteger(Magicsig::base64_url_decode($mod), 256);
238 $rsa->k = strlen($rsa->modulus->toBytes());
239 $rsa->exponent = new Math_BigInteger(Magicsig::base64_url_decode($exp), 256);
241 if ($type == 'private') {
242 $this->privateKey = $rsa;
244 $this->publicKey = $rsa;
249 * Returns the name of the crypto algorithm used for this key.
253 public function getName()
259 * Returns the name of a hash function to use for signing with this key.
263 public function getHash()
265 switch ($this->alg) {
269 throw new ServerException('Unknown or unsupported hash algorithm for Salmon');
273 * Generate base64-encoded signature for the given byte string
274 * using our private key.
276 * @param string $bytes as raw byte string
277 * @return string base64url-encoded signature
279 public function sign($bytes)
281 $sig = $this->privateKey->sign($bytes);
282 if ($sig === false) {
283 throw new ServerException('Could not sign data');
285 return Magicsig::base64_url_encode($sig);
290 * @param string $signed_bytes as raw byte string
291 * @param string $signature as base64url encoded
294 public function verify($signed_bytes, $signature)
296 $signature = self::base64_url_decode($signature);
297 return $this->publicKey->verify($signed_bytes, $signature);
301 * URL-encoding-friendly base64 variant encoding.
303 * @param string $input
306 public static function base64_url_encode($input)
308 return strtr(base64_encode($input), '+/', '-_');
312 * URL-encoding-friendly base64 variant decoding.
314 * @param string $input
317 public static function base64_url_decode($input)
319 return base64_decode(strtr($input, '-_', '+/'));