| 1 | <?php |
| 2 | /** |
| 3 | * POP client class |
| 4 | * |
| 5 | * Class depends on PHP pcre extension and fsockopen() function. Some features |
| 6 | * might require PHP 4.3.0 with OpenSSL or PHP 5.1.0+. Class checks those extra |
| 7 | * dependencies internally, if used function needs it. |
| 8 | * @copyright © 2006 The SquirrelMail Project Team |
| 9 | * @license http://opensource.org/licenses/gpl-license.php GNU Public License |
| 10 | * @version $Id$ |
| 11 | * @package plugins |
| 12 | * @subpackage mail_fetch |
| 13 | * @link http://www.ietf.org/rfc/rfc1939.txt RFC1939 |
| 14 | * @link http://www.ietf.org/rfc/rfc2449.txt POP3EXT |
| 15 | * @link http://www.ietf.org/rfc/rfc2595.txt STARTTLS |
| 16 | * @link http://www.ietf.org/rfc/rfc1734.txt AUTH command (unsupported) |
| 17 | */ |
| 18 | |
| 19 | /** |
| 20 | * POP3 client class |
| 21 | * |
| 22 | * POP connection is opened when class is constructed. All command_* methods |
| 23 | * execute specific POP commands on server. Most of other methods should be |
| 24 | * used only internally. Only login() method is public. If command returns |
| 25 | * mixed content and you expect message text, ids or something else, make sure |
| 26 | * that it is not boolean false. |
| 27 | * |
| 28 | * Basic use: |
| 29 | * 1. create object with connection params, see mail_fetch method. |
| 30 | * 2. check error buffer |
| 31 | * 3. login($username,$password) - true = login successful, false = login error. |
| 32 | * 4. command_stat() - get number of messages |
| 33 | * 5. command_list() - get message ids, use command_uidl(), if you implement |
| 34 | * 'keep mess on server' functions. |
| 35 | * 6. command_retr($some_message_id) - get message contents |
| 36 | * 7. command_dele($some_message_id) - mark message for deletion |
| 37 | * 8. command_quit() - close connection. You must close connection in order |
| 38 | * to delete messages and remove mailbox lock. |
| 39 | * @package plugins |
| 40 | * @subpackage mail_fetch |
| 41 | */ |
| 42 | class mail_fetch { |
| 43 | /** |
| 44 | * Server name |
| 45 | * @var string |
| 46 | */ |
| 47 | var $host = ''; |
| 48 | |
| 49 | /** |
| 50 | * POP connection port. |
| 51 | * Defaults to 110 on plain text connections and to 995 on TLS |
| 52 | * @var integer |
| 53 | */ |
| 54 | var $port = 0; |
| 55 | |
| 56 | /** |
| 57 | * Connection type |
| 58 | * 0 - plain text (default) |
| 59 | * 1 - tls (php 4.3 and openssl extension requirement) |
| 60 | * 2 - stls (stream_socket_enable_crypto() requirement. PHP 5.1.0, POP3 |
| 61 | * server with POP3EXT and STLS support) (untested) |
| 62 | * @var integer |
| 63 | */ |
| 64 | var $tls = 0; |
| 65 | |
| 66 | /** |
| 67 | * Authentication type |
| 68 | * |
| 69 | * Bitwise variable. If variable covers more than one authentication method, |
| 70 | * login() tries to use all of them until first successful auth. |
| 71 | * 1 - user/pass (rfc1939, default) |
| 72 | * 2 - apop (rfc1939, timestamp must be present in greeting) |
| 73 | * 3 - apop or user/pass |
| 74 | * @var integer |
| 75 | */ |
| 76 | var $auth = 1; |
| 77 | |
| 78 | /** |
| 79 | * Connection timeout |
| 80 | * @var integer |
| 81 | */ |
| 82 | var $timeout = 60; |
| 83 | |
| 84 | /** |
| 85 | * Connection resource |
| 86 | * @var stream |
| 87 | */ |
| 88 | var $conn = false; |
| 89 | |
| 90 | /** |
| 91 | * Server greeting |
| 92 | * @var string |
| 93 | */ |
| 94 | var $greeting = ''; |
| 95 | |
| 96 | /** |
| 97 | * Timestamp (with <> or empty string) |
| 98 | * @var string |
| 99 | */ |
| 100 | var $timestamp = ''; |
| 101 | |
| 102 | /** |
| 103 | * Capabilities (POP3EXT capa) |
| 104 | * @var array |
| 105 | */ |
| 106 | var $capabilities = array(); |
| 107 | |
| 108 | /** |
| 109 | * Error message buffer |
| 110 | * @var string |
| 111 | */ |
| 112 | var $error = ''; |
| 113 | |
| 114 | /** |
| 115 | * Variable is used to store last positive POP server response |
| 116 | * checked in check_response() method. Used internally to handle |
| 117 | * mixed single and multiline command responses. |
| 118 | * @var string |
| 119 | */ |
| 120 | var $response = ''; |
| 121 | |
| 122 | /** |
| 123 | * Constructor function |
| 124 | * |
| 125 | * parameter array keys |
| 126 | * 'host' - required string, address of server. ip or fqn |
| 127 | * 'port' - optional integer, port of server. |
| 128 | * 'tls' - optional integer, connection type |
| 129 | * 'timeout' - optional integer, connection timeout |
| 130 | * 'auth' - optional integer, used authentication mechanism. |
| 131 | * See description of class properties |
| 132 | * @param array $aParams connection params |
| 133 | */ |
| 134 | function mail_fetch($aParams=array()) { |
| 135 | // hostname |
| 136 | if (isset($aParams['host'])) { |
| 137 | $this->host = $aParams['host']; |
| 138 | } else { |
| 139 | return $this->set_error('Server name is not set'); |
| 140 | } |
| 141 | // tls |
| 142 | if (isset($aParams['tls'])) { |
| 143 | $this->tls = (int) $aParams['tls']; |
| 144 | } |
| 145 | // port |
| 146 | if (isset($aParams['port'])) { |
| 147 | $this->port = (int) $aParams['port']; |
| 148 | } |
| 149 | // set default ports |
| 150 | if ($this->port == 0) { |
| 151 | if ($this->tls===1) { |
| 152 | // pops |
| 153 | $this->port = 995; |
| 154 | } else { |
| 155 | // pop3 |
| 156 | $this->port = 110; |
| 157 | } |
| 158 | } |
| 159 | // timeout |
| 160 | if (isset($aParams['timeout'])) { |
| 161 | $this->timeout = (int) $aParams['timeout']; |
| 162 | } |
| 163 | // authentication mech |
| 164 | if (isset($aParams['auth'])) { |
| 165 | $this->auth = (int) $aParams['auth']; |
| 166 | } |
| 167 | |
| 168 | // open connection |
| 169 | $this->open(); |
| 170 | } |
| 171 | |
| 172 | // Generic methods to handle connection and login operations. |
| 173 | |
| 174 | /** |
| 175 | * Opens pop connection |
| 176 | * |
| 177 | * Command handles TLS and STLS connection differences and fills capabilities |
| 178 | * array with RFC2449 CAPA data. |
| 179 | * @return boolean |
| 180 | */ |
| 181 | function open() { |
| 182 | if ($this->conn) { |
| 183 | return true; |
| 184 | } |
| 185 | |
| 186 | if ($this->tls===1) { |
| 187 | if (! $this->check_php_version(4,3) || ! extension_loaded('openssl')) { |
| 188 | return $this->set_error('Used PHP version does not support functions required for POP TLS.'); |
| 189 | } |
| 190 | $target = 'tls://' . $this->host; |
| 191 | } else { |
| 192 | $target = $this->host; |
| 193 | } |
| 194 | |
| 195 | $this->conn = @fsockopen($target, $this->port, $errno, $errstr, $this->timeout); |
| 196 | |
| 197 | if (!$this->conn) { |
| 198 | $error = sprintf('Error %d: ',$errno) . $errstr; |
| 199 | return $this->set_error($error); |
| 200 | } |
| 201 | |
| 202 | // read greeting |
| 203 | $this->greeting = trim(fgets($this->conn)); |
| 204 | |
| 205 | // check greeting for errors and extract timestamp |
| 206 | if (preg_match('/^-ERR (.+)/',$this->greeting,$matches)) { |
| 207 | return $this->set_error($matches[1],true); |
| 208 | } elseif (preg_match('/^\+OK.+(<.+>)/',$this->greeting,$matches)) { |
| 209 | $this->timestamp = $matches[1]; |
| 210 | } |
| 211 | |
| 212 | /** |
| 213 | * fill capability only when connection uses some non-rfc1939 |
| 214 | * authentication type (currently unsupported) or STARTTLS. |
| 215 | * Command is not part of rfc1939 and we don't have to use it |
| 216 | * in simple POP connection. |
| 217 | */ |
| 218 | if ($this->auth > 3 || $this->tls===2) { |
| 219 | $this->command_capa(); |
| 220 | } |
| 221 | |
| 222 | // STARTTLS support |
| 223 | if ($this->tls===2) { |
| 224 | return $this->command_stls(); |
| 225 | } |
| 226 | |
| 227 | return true; |
| 228 | } |
| 229 | |
| 230 | /** |
| 231 | * Reads first response line and checks it for errors |
| 232 | * @return boolean true = success, false = failure, check error buffer |
| 233 | */ |
| 234 | function check_response() { |
| 235 | $line = fgets($this->conn); |
| 236 | if (preg_match('/^-ERR (.+)/',$line,$matches)) { |
| 237 | return $this->set_error($matches[1]); |
| 238 | } elseif (preg_match('/^\+OK/',$line)) { |
| 239 | $this->response = trim($line); |
| 240 | return true; |
| 241 | } else { |
| 242 | $this->response = trim($line); |
| 243 | return $this->set_error('Unknown response'); |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | /** |
| 248 | * Standard SquirrelMail function copied to class in order to make class |
| 249 | * independent from SquirrelMail. |
| 250 | */ |
| 251 | function check_php_version ($a = '0', $b = '0', $c = '0') { |
| 252 | return version_compare ( PHP_VERSION, "$a.$b.$c", 'ge' ); |
| 253 | } |
| 254 | |
| 255 | /** |
| 256 | * Generic login wrapper |
| 257 | * |
| 258 | * Connection is not closed on login error (unless POP server drops |
| 259 | * connection) |
| 260 | * @param string $username |
| 261 | * @param string $password |
| 262 | * @return boolean |
| 263 | */ |
| 264 | function login($username,$password) { |
| 265 | $ret = false; |
| 266 | |
| 267 | // RFC1939 APOP authentication |
| 268 | if (! $ret && $this->auth & 2) { |
| 269 | // clean error buffer |
| 270 | $this->error = ''; |
| 271 | // APOP login |
| 272 | $ret = $this->command_apop($username,$password); |
| 273 | } |
| 274 | |
| 275 | // RFC1939 USER authentication |
| 276 | if (! $ret && $this->auth & 1) { |
| 277 | // clean error buffer |
| 278 | $this->error = ''; |
| 279 | // Default to USER/PASS login |
| 280 | if (! $this->command_user($username)) { |
| 281 | // error is already in error buffer |
| 282 | $ret = false; |
| 283 | } else { |
| 284 | $ret = $this->command_pass($password); |
| 285 | } |
| 286 | } |
| 287 | return $ret; |
| 288 | } |
| 289 | |
| 290 | /** |
| 291 | * Sets error in error buffer and returns boolean false |
| 292 | * @param string $error Error message |
| 293 | * @param boolean $close_conn Do we have to close connection |
| 294 | * @return boolean false |
| 295 | */ |
| 296 | function set_error($error,$close_conn=false) { |
| 297 | $this->error = $error; |
| 298 | if ($close_conn) { |
| 299 | $this->command_quit(); |
| 300 | } |
| 301 | return false; |
| 302 | } |
| 303 | |
| 304 | // POP (rfc 1939) commands |
| 305 | |
| 306 | /** |
| 307 | * Gets mailbox status |
| 308 | * array with 'count' and 'size' keys |
| 309 | * @return mixed array or boolean false |
| 310 | */ |
| 311 | function command_stat() { |
| 312 | fwrite($this->conn,"STAT\r\n"); |
| 313 | $response = fgets($this->conn); |
| 314 | if (preg_match('/^\+OK (\d+) (\d+)/',$response,$matches)) { |
| 315 | return array('count' => $matches[1], |
| 316 | 'size' => $matches[2]); |
| 317 | } else { |
| 318 | return $this->set_error('stat command failed'); |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | /** |
| 323 | * List mailbox messages |
| 324 | * @param integer $msg |
| 325 | * @return mixed array with message ids (keys) and sizes (values) or boolean false |
| 326 | */ |
| 327 | function command_list($msg='') { |
| 328 | fwrite($this->conn,"LIST $msg\r\n"); |
| 329 | |
| 330 | if($this->check_response()) { |
| 331 | $ret = array(); |
| 332 | if (!empty($msg)) { |
| 333 | list($ok,$msg_id,$size) = explode(' ',trim($this->response)); |
| 334 | $ret[$msg_id] = $size; |
| 335 | } else { |
| 336 | while($line = fgets($this->conn)) { |
| 337 | if (trim($line)=='.') { |
| 338 | break; |
| 339 | } else { |
| 340 | list($msg_id,$size) = explode(' ',trim($line)); |
| 341 | $ret[$msg_id] = $size; |
| 342 | } |
| 343 | } |
| 344 | } |
| 345 | return $ret; |
| 346 | } else { |
| 347 | return false; |
| 348 | } |
| 349 | } |
| 350 | |
| 351 | /** |
| 352 | * Gets message text |
| 353 | * @param integer $msg message id |
| 354 | * @return mixed rfc822 message (CRLF line endings) or boolean false |
| 355 | */ |
| 356 | function command_retr($msg) { |
| 357 | fwrite($this->conn,"RETR $msg\r\n"); |
| 358 | |
| 359 | if($this->check_response()) { |
| 360 | $ret = ''; |
| 361 | while($line = fgets($this->conn)) { |
| 362 | if (trim($line)=='.') { |
| 363 | break; |
| 364 | } else { |
| 365 | $ret.= $line; |
| 366 | } |
| 367 | } |
| 368 | return $ret; |
| 369 | } else { |
| 370 | return false; |
| 371 | } |
| 372 | } |
| 373 | |
| 374 | /** |
| 375 | * @param integer $msg |
| 376 | * @return boolean |
| 377 | */ |
| 378 | function command_dele($msg) { |
| 379 | fwrite($this->conn,"DELE $msg\r\n"); |
| 380 | return $this->check_response(); |
| 381 | } |
| 382 | |
| 383 | /** |
| 384 | * POP noop command |
| 385 | * @return boolean |
| 386 | */ |
| 387 | function command_noop() { |
| 388 | fwrite($this->conn,"NOOP\r\n"); |
| 389 | return $this->check_response(); |
| 390 | } |
| 391 | |
| 392 | /** |
| 393 | * Resets message state |
| 394 | * @return boolean |
| 395 | */ |
| 396 | function command_rset() { |
| 397 | fwrite($this->conn,"RSET\r\n"); |
| 398 | return $this->check_response(); |
| 399 | } |
| 400 | |
| 401 | /** |
| 402 | * Closes POP connection |
| 403 | */ |
| 404 | function command_quit() { |
| 405 | fwrite($this->conn,"QUIT\r\n"); |
| 406 | fclose($this->conn); |
| 407 | $this->conn = false; |
| 408 | } |
| 409 | |
| 410 | // Optional RFC1939 commands |
| 411 | |
| 412 | /** |
| 413 | * Gets message headers and $n of body lines. |
| 414 | * |
| 415 | * Command is optional and not required by rfc1939 |
| 416 | * @param integer $msg |
| 417 | * @param integer $n |
| 418 | * @return string or boolean false |
| 419 | */ |
| 420 | function command_top($msg,$n) { |
| 421 | fwrite($this->conn,"TOP $msg $n\r\n"); |
| 422 | |
| 423 | if($this->check_response()) { |
| 424 | $ret = ''; |
| 425 | while($line = fgets($this->conn)) { |
| 426 | if (trim($line)=='.') { |
| 427 | break; |
| 428 | } else { |
| 429 | $ret.= $line; |
| 430 | } |
| 431 | } |
| 432 | return $ret; |
| 433 | } else { |
| 434 | return false; |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * Gets unique message ids |
| 440 | * Command is optional and not required by rfc1939 |
| 441 | * @param integer $msg message id |
| 442 | * @return mixed array with message ids (keys) and unique ids (values) |
| 443 | * or boolean false |
| 444 | */ |
| 445 | function command_uidl($msg='') { |
| 446 | fwrite($this->conn,"UIDL $msg\r\n"); |
| 447 | if($this->check_response()) { |
| 448 | $ids = array(); |
| 449 | if (!empty($msg)) { |
| 450 | list($ok,$msg_id,$unique_id) = explode(' ',trim($this->response)); |
| 451 | $ids[$msg_id] = $unique_id; |
| 452 | } else { |
| 453 | while($line = fgets($this->conn)) { |
| 454 | if (trim($line)=='.') { |
| 455 | break; |
| 456 | } else { |
| 457 | list($msg_id,$unique_id) = explode(' ',trim($line)); |
| 458 | $ids[$msg_id] = $unique_id; |
| 459 | } |
| 460 | } |
| 461 | } |
| 462 | return $ids; |
| 463 | } else { |
| 464 | return false; |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | /** |
| 469 | * USER authentication (username command) |
| 470 | * |
| 471 | * Command is optional and not required by rfc1939. If command |
| 472 | * is successful, pass command must be executed after it. |
| 473 | * @param string $username |
| 474 | * @return boolean true = success, false = failure. |
| 475 | */ |
| 476 | function command_user($username) { |
| 477 | fwrite($this->conn,"USER $username\r\n"); |
| 478 | return $this->check_response(); |
| 479 | } |
| 480 | |
| 481 | /** |
| 482 | * USER authentication (password command) |
| 483 | * |
| 484 | * Command is optional and not required by rfc1939. Requires |
| 485 | * successful user command. |
| 486 | * @param string $password |
| 487 | * @return boolean true = success, false = failure. |
| 488 | */ |
| 489 | function command_pass($password) { |
| 490 | fwrite($this->conn,"PASS $password\r\n"); |
| 491 | return $this->check_response(); |
| 492 | } |
| 493 | |
| 494 | /** |
| 495 | * APOP authentication |
| 496 | * |
| 497 | * Command is optional and not required by rfc1939. APOP support |
| 498 | * requires plain text passwords stored on server and some servers |
| 499 | * don't support it. Standard qmail pop3d declares apop support |
| 500 | * without checking if checkpassword supports it. |
| 501 | * @param string $username |
| 502 | * @param string $password |
| 503 | * @return boolean true = success, false = failure. |
| 504 | */ |
| 505 | function command_apop($username,$password) { |
| 506 | if (empty($this->timestamp)) { |
| 507 | return $this->set_error('APOP is not supported by selected server.'); |
| 508 | } |
| 509 | $digest = md5($this->timestamp . $password); |
| 510 | |
| 511 | fwrite($this->conn,"APOP $username $digest\r\n"); |
| 512 | return $this->check_response(); |
| 513 | } |
| 514 | |
| 515 | // RFC2449 POP3EXT |
| 516 | |
| 517 | /** |
| 518 | * Checks pop server capabilities |
| 519 | * |
| 520 | * RFC2449. Fills capabilities array. |
| 521 | * @return void |
| 522 | */ |
| 523 | function command_capa() { |
| 524 | fwrite($this->conn,"CAPA\r\n"); |
| 525 | if ($this->check_response()) { |
| 526 | // reset array. capabilities depend on authorization state |
| 527 | $this->capabilities = array(); |
| 528 | while($line = fgets($this->conn)) { |
| 529 | if (trim($line)=='.') { |
| 530 | break; |
| 531 | } else { |
| 532 | $this->capabilities[] = trim($line); |
| 533 | } |
| 534 | } |
| 535 | } else { |
| 536 | // if capa fails, error buffer contains error message. |
| 537 | // Clean error buffer, |
| 538 | // if POP3EXT is not supported, capability array will be empty |
| 539 | $this->error = ''; |
| 540 | } |
| 541 | } |
| 542 | |
| 543 | // RFC2595 STARTTLS |
| 544 | |
| 545 | /** |
| 546 | * RFC 2595 POP STARTTLS support |
| 547 | * @return boolean |
| 548 | */ |
| 549 | function command_stls() { |
| 550 | if (! function_exists('stream_socket_enable_crypto')) { |
| 551 | return $this->set_error('Used PHP version does not support functions required for POP STLS.',true); |
| 552 | } elseif (in_array('STLS',$this->capabilities)) { |
| 553 | return $this->set_error('Selected POP3 server does not support STLS.',true); |
| 554 | } |
| 555 | fwrite($this->conn,"STLS\r\n"); |
| 556 | if (! $this->check_response()) { |
| 557 | return false; |
| 558 | } |
| 559 | |
| 560 | if (@stream_socket_enable_crypto($this->conn,true,STREAM_CRYPTO_METHOD_TLS_CLIENT)) { |
| 561 | // starttls was successful (rfc2595 4. POP3 STARTTLS extension.) |
| 562 | // get new CAPA response |
| 563 | $this->command_capa(); |
| 564 | } else { |
| 565 | /** stream_socket_enable_crypto() call failed. */ |
| 566 | return $this->set_error('Unable to start TLS.',true); |
| 567 | } |
| 568 | return true; |
| 569 | } |
| 570 | } |