| commit | author | age | ||
| 48e9c1 | 1 | <?php |
| T | 2 | |
| 3 | /* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */ | |
| 4 | ||
| 5 | /** | |
| 6 | * Crypt_GPG is a package to use GPG from PHP | |
| 7 | * | |
| 8 | * This file contains an object that handles GPG's status output for the | |
| 9 | * decrypt operation. | |
| 10 | * | |
| 11 | * PHP version 5 | |
| 12 | * | |
| 13 | * LICENSE: | |
| 14 | * | |
| 15 | * This library is free software; you can redistribute it and/or modify | |
| 16 | * it under the terms of the GNU Lesser General Public License as | |
| 17 | * published by the Free Software Foundation; either version 2.1 of the | |
| 18 | * License, or (at your option) any later version. | |
| 19 | * | |
| 20 | * This library is distributed in the hope that it will be useful, | |
| 21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 23 | * Lesser General Public License for more details. | |
| 24 | * | |
| 25 | * You should have received a copy of the GNU Lesser General Public | |
| 26 | * License along with this library; if not, write to the Free Software | |
| 27 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 28 | * | |
| 29 | * @category Encryption | |
| 30 | * @package Crypt_GPG | |
| 31 | * @author Michael Gauthier <mike@silverorange.com> | |
| 32 | * @copyright 2008-2009 silverorange | |
| 33 | * @license http://www.gnu.org/copyleft/lesser.html LGPL License 2.1 | |
| 34 | * @version CVS: $Id: DecryptStatusHandler.php 302814 2010-08-26 15:43:07Z gauthierm $ | |
| 35 | * @link http://pear.php.net/package/Crypt_GPG | |
| 36 | * @link http://www.gnupg.org/ | |
| 37 | */ | |
| 38 | ||
| 39 | /** | |
| 40 | * Crypt_GPG base class | |
| 41 | */ | |
| 42 | require_once 'Crypt/GPG.php'; | |
| 43 | ||
| 44 | /** | |
| 45 | * GPG exception classes | |
| 46 | */ | |
| 47 | require_once 'Crypt/GPG/Exceptions.php'; | |
| 48 | ||
| 49 | ||
| 50 | /** | |
| 51 | * Status line handler for the decrypt operation | |
| 52 | * | |
| 53 | * This class is used internally by Crypt_GPG and does not need be used | |
| 54 | * directly. See the {@link Crypt_GPG} class for end-user API. | |
| 55 | * | |
| 56 | * This class is responsible for sending the passphrase commands when required | |
| 57 | * by the {@link Crypt_GPG::decrypt()} method. See <b>doc/DETAILS</b> in the | |
| 58 | * {@link http://www.gnupg.org/download/ GPG distribution} for detailed | |
| 59 | * information on GPG's status output for the decrypt operation. | |
| 60 | * | |
| 61 | * This class is also responsible for parsing error status and throwing a | |
| 62 | * meaningful exception in the event that decryption fails. | |
| 63 | * | |
| 64 | * @category Encryption | |
| 65 | * @package Crypt_GPG | |
| 66 | * @author Michael Gauthier <mike@silverorange.com> | |
| 67 | * @copyright 2008 silverorange | |
| 68 | * @license http://www.gnu.org/copyleft/lesser.html LGPL License 2.1 | |
| 69 | * @link http://pear.php.net/package/Crypt_GPG | |
| 70 | * @link http://www.gnupg.org/ | |
| 71 | */ | |
| 72 | class Crypt_GPG_DecryptStatusHandler | |
| 73 | { | |
| 74 | // {{{ protected properties | |
| 75 | ||
| 76 | /** | |
| 77 | * Keys used to decrypt | |
| 78 | * | |
| 79 | * The array is of the form: | |
| 80 | * <code> | |
| 81 | * array( | |
| 82 | * $key_id => array( | |
| 83 | * 'fingerprint' => $fingerprint, | |
| 84 | * 'passphrase' => $passphrase | |
| 85 | * ) | |
| 86 | * ); | |
| 87 | * </code> | |
| 88 | * | |
| 89 | * @var array | |
| 90 | */ | |
| 91 | protected $keys = array(); | |
| 92 | ||
| 93 | /** | |
| 94 | * Engine used to which passphrases are passed | |
| 95 | * | |
| 96 | * @var Crypt_GPG_Engine | |
| 97 | */ | |
| 98 | protected $engine = null; | |
| 99 | ||
| 100 | /** | |
| 101 | * The id of the current sub-key used for decryption | |
| 102 | * | |
| 103 | * @var string | |
| 104 | */ | |
| 105 | protected $currentSubKey = ''; | |
| 106 | ||
| 107 | /** | |
| 108 | * Whether or not decryption succeeded | |
| 109 | * | |
| 110 | * If the message is only signed (compressed) and not encrypted, this is | |
| 111 | * always true. If the message is encrypted, this flag is set to false | |
| 112 | * until we know the decryption succeeded. | |
| 113 | * | |
| 114 | * @var boolean | |
| 115 | */ | |
| 116 | protected $decryptionOkay = true; | |
| 117 | ||
| 118 | /** | |
| 119 | * Whether or not there was no data for decryption | |
| 120 | * | |
| 121 | * @var boolean | |
| 122 | */ | |
| 123 | protected $noData = false; | |
| 124 | ||
| 125 | /** | |
| 126 | * Keys for which the passhprase is missing | |
| 127 | * | |
| 128 | * This contains primary user ids indexed by sub-key id and is used to | |
| 129 | * create helpful exception messages. | |
| 130 | * | |
| 131 | * @var array | |
| 132 | */ | |
| 133 | protected $missingPassphrases = array(); | |
| 134 | ||
| 135 | /** | |
| 136 | * Keys for which the passhprase is incorrect | |
| 137 | * | |
| 138 | * This contains primary user ids indexed by sub-key id and is used to | |
| 139 | * create helpful exception messages. | |
| 140 | * | |
| 141 | * @var array | |
| 142 | */ | |
| 143 | protected $badPassphrases = array(); | |
| 144 | ||
| 145 | /** | |
| 146 | * Keys that can be used to decrypt the data but are missing from the | |
| 147 | * keychain | |
| 148 | * | |
| 149 | * This is an array with both the key and value being the sub-key id of | |
| 150 | * the missing keys. | |
| 151 | * | |
| 152 | * @var array | |
| 153 | */ | |
| 154 | protected $missingKeys = array(); | |
| 155 | ||
| 156 | // }}} | |
| 157 | // {{{ __construct() | |
| 158 | ||
| 159 | /** | |
| 160 | * Creates a new decryption status handler | |
| 161 | * | |
| 162 | * @param Crypt_GPG_Engine $engine the GPG engine to which passphrases are | |
| 163 | * passed. | |
| 164 | * @param array $keys the decryption keys to use. | |
| 165 | */ | |
| 166 | public function __construct(Crypt_GPG_Engine $engine, array $keys) | |
| 167 | { | |
| 168 | $this->engine = $engine; | |
| 169 | $this->keys = $keys; | |
| 170 | } | |
| 171 | ||
| 172 | // }}} | |
| 173 | // {{{ handle() | |
| 174 | ||
| 175 | /** | |
| 176 | * Handles a status line | |
| 177 | * | |
| 178 | * @param string $line the status line to handle. | |
| 179 | * | |
| 180 | * @return void | |
| 181 | */ | |
| 182 | public function handle($line) | |
| 183 | { | |
| 184 | $tokens = explode(' ', $line); | |
| 185 | switch ($tokens[0]) { | |
| 186 | case 'ENC_TO': | |
| 187 | // Now we know the message is encrypted. Set flag to check if | |
| 188 | // decryption succeeded. | |
| 189 | $this->decryptionOkay = false; | |
| 190 | ||
| 191 | // this is the new key message | |
| 192 | $this->currentSubKeyId = $tokens[1]; | |
| 193 | break; | |
| 194 | ||
| 195 | case 'NEED_PASSPHRASE': | |
| 196 | // send passphrase to the GPG engine | |
| 197 | $subKeyId = $tokens[1]; | |
| 198 | if (array_key_exists($subKeyId, $this->keys)) { | |
| 199 | $passphrase = $this->keys[$subKeyId]['passphrase']; | |
| 200 | $this->engine->sendCommand($passphrase); | |
| 201 | } else { | |
| 202 | $this->engine->sendCommand(''); | |
| 203 | } | |
| 204 | break; | |
| 205 | ||
| 206 | case 'USERID_HINT': | |
| 207 | // remember the user id for pretty exception messages | |
| 208 | $this->badPassphrases[$tokens[1]] | |
| 209 | = implode(' ', array_splice($tokens, 2)); | |
| 210 | ||
| 211 | break; | |
| 212 | ||
| 213 | case 'GOOD_PASSPHRASE': | |
| 214 | // if we got a good passphrase, remove the key from the list of | |
| 215 | // bad passphrases. | |
| 216 | unset($this->badPassphrases[$this->currentSubKeyId]); | |
| 217 | break; | |
| 218 | ||
| 219 | case 'MISSING_PASSPHRASE': | |
| 220 | $this->missingPassphrases[$this->currentSubKeyId] | |
| 221 | = $this->currentSubKeyId; | |
| 222 | ||
| 223 | break; | |
| 224 | ||
| 225 | case 'NO_SECKEY': | |
| 226 | // note: this message is also received if there are multiple | |
| 227 | // recipients and a previous key had a correct passphrase. | |
| 228 | $this->missingKeys[$tokens[1]] = $tokens[1]; | |
| 229 | break; | |
| 230 | ||
| 231 | case 'NODATA': | |
| 232 | $this->noData = true; | |
| 233 | break; | |
| 234 | ||
| 235 | case 'DECRYPTION_OKAY': | |
| 236 | // If the message is encrypted, this is the all-clear signal. | |
| 237 | $this->decryptionOkay = true; | |
| 238 | break; | |
| 239 | } | |
| 240 | } | |
| 241 | ||
| 242 | // }}} | |
| 243 | // {{{ throwException() | |
| 244 | ||
| 245 | /** | |
| 246 | * Takes the final status of the decrypt operation and throws an | |
| 247 | * appropriate exception | |
| 248 | * | |
| 249 | * If decryption was successful, no exception is thrown. | |
| 250 | * | |
| 251 | * @return void | |
| 252 | * | |
| 253 | * @throws Crypt_GPG_KeyNotFoundException if the private key needed to | |
| 254 | * decrypt the data is not in the user's keyring. | |
| 255 | * | |
| 256 | * @throws Crypt_GPG_NoDataException if specified data does not contain | |
| 257 | * GPG encrypted data. | |
| 258 | * | |
| 259 | * @throws Crypt_GPG_BadPassphraseException if a required passphrase is | |
| 260 | * incorrect or if a required passphrase is not specified. See | |
| 261 | * {@link Crypt_GPG::addDecryptKey()}. | |
| 262 | * | |
| 263 | * @throws Crypt_GPG_Exception if an unknown or unexpected error occurs. | |
| 264 | * Use the <i>debug</i> option and file a bug report if these | |
| 265 | * exceptions occur. | |
| 266 | */ | |
| 267 | public function throwException() | |
| 268 | { | |
| 269 | $code = Crypt_GPG::ERROR_NONE; | |
| 270 | ||
| 271 | if (!$this->decryptionOkay) { | |
| 272 | if (count($this->badPassphrases) > 0) { | |
| 273 | $code = Crypt_GPG::ERROR_BAD_PASSPHRASE; | |
| 274 | } elseif (count($this->missingKeys) > 0) { | |
| 275 | $code = Crypt_GPG::ERROR_KEY_NOT_FOUND; | |
| 276 | } else { | |
| 277 | $code = Crypt_GPG::ERROR_UNKNOWN; | |
| 278 | } | |
| 279 | } elseif ($this->noData) { | |
| 280 | $code = Crypt_GPG::ERROR_NO_DATA; | |
| 281 | } | |
| 282 | ||
| 283 | switch ($code) { | |
| 284 | case Crypt_GPG::ERROR_NONE: | |
| 285 | break; | |
| 286 | ||
| 287 | case Crypt_GPG::ERROR_KEY_NOT_FOUND: | |
| 288 | if (count($this->missingKeys) > 0) { | |
| 289 | $keyId = reset($this->missingKeys); | |
| 290 | } else { | |
| 291 | $keyId = ''; | |
| 292 | } | |
| 293 | throw new Crypt_GPG_KeyNotFoundException( | |
| 294 | 'Cannot decrypt data. No suitable private key is in the ' . | |
| 295 | 'keyring. Import a suitable private key before trying to ' . | |
| 296 | 'decrypt this data.', $code, $keyId); | |
| 297 | ||
| 298 | case Crypt_GPG::ERROR_BAD_PASSPHRASE: | |
| 299 | $badPassphrases = array_diff_key( | |
| 300 | $this->badPassphrases, | |
| 301 | $this->missingPassphrases | |
| 302 | ); | |
| 303 | ||
| 304 | $missingPassphrases = array_intersect_key( | |
| 305 | $this->badPassphrases, | |
| 306 | $this->missingPassphrases | |
| 307 | ); | |
| 308 | ||
| 309 | $message = 'Cannot decrypt data.'; | |
| 310 | if (count($badPassphrases) > 0) { | |
| 311 | $message = ' Incorrect passphrase provided for keys: "' . | |
| 312 | implode('", "', $badPassphrases) . '".'; | |
| 313 | } | |
| 314 | if (count($missingPassphrases) > 0) { | |
| 315 | $message = ' No passphrase provided for keys: "' . | |
| 316 | implode('", "', $badPassphrases) . '".'; | |
| 317 | } | |
| 318 | ||
| 319 | throw new Crypt_GPG_BadPassphraseException($message, $code, | |
| 320 | $badPassphrases, $missingPassphrases); | |
| 321 | ||
| 322 | case Crypt_GPG::ERROR_NO_DATA: | |
| 323 | throw new Crypt_GPG_NoDataException( | |
| 324 | 'Cannot decrypt data. No PGP encrypted data was found in '. | |
| 325 | 'the provided data.', $code); | |
| 326 | ||
| 327 | default: | |
| 328 | throw new Crypt_GPG_Exception( | |
| 329 | 'Unknown error decrypting data.', $code); | |
| 330 | } | |
| 331 | } | |
| 332 | ||
| 333 | // }}} | |
| 334 | } | |
| 335 | ||
| 336 | ?> | |
