class-authentication.php
3 years ago
class-backup-codes.php
4 years ago
class-backupcodes.php
4 years ago
class-login.php
3 years ago
class-open-ssl.php
3 years ago
index.php
5 years ago
class-authentication.php
591 lines
| 1 | <?php |
| 2 | /** |
| 3 | * Responsible for WP2FA user's authentication. |
| 4 | * |
| 5 | * @package wp2fa |
| 6 | * @subpackage authentication |
| 7 | * @copyright 2021 WP White Security |
| 8 | * @license https://www.apache.org/licenses/LICENSE-2.0 Apache License 2.0 |
| 9 | * @link https://wordpress.org/plugins/wp-2fa/ |
| 10 | */ |
| 11 | |
| 12 | /** |
| 13 | * Class for handling general authentication tasks. |
| 14 | * |
| 15 | * @since 0.1-dev |
| 16 | * |
| 17 | * @package WP2FA |
| 18 | */ |
| 19 | |
| 20 | namespace WP2FA\Authenticator; |
| 21 | |
| 22 | use Endroid\QrCode\QrCode; |
| 23 | use WP2FA\Authenticator\Open_SSL; |
| 24 | use Endroid\QrCode\Writer\SvgWriter; |
| 25 | use WP2FA\Admin\Helpers\User_Helper; |
| 26 | use WP2FA\Admin\Controllers\Login_Attempts; |
| 27 | |
| 28 | /** |
| 29 | * Authenticator class |
| 30 | */ |
| 31 | class Authentication { |
| 32 | |
| 33 | const DEFAULT_KEY_BIT_SIZE = 160; |
| 34 | const DEFAULT_CRYPTO = 'sha1'; |
| 35 | const DEFAULT_DIGIT_COUNT = 6; |
| 36 | const DEFAULT_TIME_STEP_SEC = 30; |
| 37 | const DEFAULT_TIME_STEP_ALLOWANCE = 4; |
| 38 | |
| 39 | /** |
| 40 | * Holds the name of the meta key for the allowed login attempts |
| 41 | * |
| 42 | * @var string |
| 43 | * |
| 44 | * @since 2.0.0 |
| 45 | */ |
| 46 | private static $login_num_meta_key = WP_2FA_PREFIX . 'email-login-attempts'; |
| 47 | |
| 48 | /** |
| 49 | * The login attempts class |
| 50 | * |
| 51 | * @var \WP2FA\Admin\Controllers\Login_Attempts |
| 52 | * |
| 53 | * @since 2.0.0 |
| 54 | */ |
| 55 | private static $login_attempts = null; |
| 56 | |
| 57 | /** |
| 58 | * String with the base32 characters |
| 59 | * |
| 60 | * @var string |
| 61 | */ |
| 62 | private static $base_32_chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ234567'; |
| 63 | |
| 64 | /** |
| 65 | * String with the decrypted key |
| 66 | * |
| 67 | * @var string |
| 68 | */ |
| 69 | private static $decrypted_key = ''; |
| 70 | |
| 71 | /** |
| 72 | * Gemerate QR code |
| 73 | * |
| 74 | * @param string $name Username. |
| 75 | * @param string $key Auth key. |
| 76 | * @param string $title Site title. |
| 77 | * @return string QR code URL. |
| 78 | */ |
| 79 | public static function get_google_qr_code( $name, $key, $title = null ) { |
| 80 | // Encode to support spaces, question marks and other characters. |
| 81 | $name = rawurlencode( $name ); |
| 82 | |
| 83 | self::decrypt_key_if_needed( $key ); |
| 84 | |
| 85 | $target_url = ( 'otpauth://totp/' . $name . '?secret=' . $key ); |
| 86 | if ( isset( $title ) ) { |
| 87 | $target_url .= ( '&issuer=' . rawurlencode( $title ) ); |
| 88 | } |
| 89 | |
| 90 | $qr = new QrCode( $target_url ); |
| 91 | $qr->setWriterOptions( array( 'exclude_xml_declaration' => true ) ); |
| 92 | $writer = new SvgWriter(); |
| 93 | $result = $writer->writeString( $qr ); |
| 94 | |
| 95 | return 'data:image/svg+xml;base64,' . base64_encode( $result ); // phpcs:ignore |
| 96 | } |
| 97 | |
| 98 | /** |
| 99 | * Generates key |
| 100 | * |
| 101 | * @param int $bitsize Nume of bits to use for key. |
| 102 | * |
| 103 | * @return string $bitsize long string composed of available base32 chars. |
| 104 | */ |
| 105 | public static function generate_key( $bitsize = self::DEFAULT_KEY_BIT_SIZE ) { |
| 106 | $bytes = ceil( $bitsize / 8 ); |
| 107 | $secret = wp_generate_password( $bytes, true, true ); |
| 108 | |
| 109 | $secret = Open_SSL::encrypt( self::base32_encode( $secret ) ); |
| 110 | |
| 111 | if ( Open_SSL::is_ssl_available() ) { |
| 112 | $secret = 'wps_' . $secret; |
| 113 | } |
| 114 | |
| 115 | return $secret; |
| 116 | } |
| 117 | /** |
| 118 | * Returns a base32 encoded string. |
| 119 | * |
| 120 | * @param string $string String to be encoded using base32. |
| 121 | * |
| 122 | * @return string base32 encoded string without padding. |
| 123 | */ |
| 124 | public static function base32_encode( $string ) { |
| 125 | if ( empty( $string ) ) { |
| 126 | return ''; |
| 127 | } |
| 128 | |
| 129 | $binary_string = ''; |
| 130 | |
| 131 | foreach ( str_split( $string ) as $character ) { |
| 132 | $binary_string .= str_pad( base_convert( ord( $character ), 10, 2 ), 8, '0', STR_PAD_LEFT ); |
| 133 | } |
| 134 | |
| 135 | $five_bit_sections = str_split( $binary_string, 5 ); |
| 136 | $base32_string = ''; |
| 137 | |
| 138 | foreach ( $five_bit_sections as $five_bit_section ) { |
| 139 | $base32_string .= self::$base_32_chars[ base_convert( str_pad( $five_bit_section, 5, '0' ), 2, 10 ) ]; |
| 140 | } |
| 141 | |
| 142 | return $base32_string; |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * Get the TOTP secret key for a user. |
| 147 | * |
| 148 | * @param int $user_id User ID. |
| 149 | * |
| 150 | * @return string |
| 151 | */ |
| 152 | public static function get_user_totp_key( $user_id ) { |
| 153 | |
| 154 | $key = (string) User_Helper::get_user_totp_key( $user_id ); |
| 155 | |
| 156 | $test = $key; |
| 157 | |
| 158 | if ( Open_SSL::is_ssl_available() && false !== \strpos( $key, 'ssl_' ) ) { |
| 159 | |
| 160 | /** |
| 161 | * Old key detected - convert. |
| 162 | */ |
| 163 | $key = Open_SSL::decrypt_legacy( substr( $key, 4 ) ); |
| 164 | |
| 165 | User_Helper::remove_user_totp_key(); |
| 166 | |
| 167 | $secret = Open_SSL::encrypt( $key ); |
| 168 | |
| 169 | if ( Open_SSL::is_ssl_available() ) { |
| 170 | $secret = 'wps_' . $secret; |
| 171 | } |
| 172 | |
| 173 | User_Helper::set_user_totp_key( $key, $user_id ); |
| 174 | |
| 175 | $test = $key = (string) User_Helper::get_user_totp_key( $user_id ); // phpcs:ignore |
| 176 | } |
| 177 | |
| 178 | self::decrypt_key_if_needed( $test ); |
| 179 | |
| 180 | if ( ! self::is_valid_key( $test ) ) { |
| 181 | $key = self::generate_key(); |
| 182 | User_Helper::set_user_totp_key( $key, $user_id ); |
| 183 | } |
| 184 | |
| 185 | return $key; |
| 186 | } |
| 187 | |
| 188 | /** |
| 189 | * Check if the TOTP secret key has a proper format. |
| 190 | * |
| 191 | * @param string $key TOTP secret key. |
| 192 | * |
| 193 | * @return boolean |
| 194 | */ |
| 195 | public static function is_valid_key( $key ) { |
| 196 | self::decrypt_key_if_needed( $key ); |
| 197 | |
| 198 | $check = sprintf( '/^[%s]+$/', self::$base_32_chars ); |
| 199 | |
| 200 | if ( 1 === preg_match( $check, $key ) ) { |
| 201 | return true; |
| 202 | } |
| 203 | |
| 204 | return false; |
| 205 | } |
| 206 | |
| 207 | /** |
| 208 | * Checks if a given code is valid for a given key, allowing for a certain amount of time drift |
| 209 | * |
| 210 | * @param string $key The share secret key to use. |
| 211 | * @param string $authcode The code to test. |
| 212 | * |
| 213 | * @return bool Whether the code is valid within the time frame |
| 214 | */ |
| 215 | public static function is_valid_authcode( $key, $authcode ) { |
| 216 | |
| 217 | self::decrypt_key_if_needed( $key ); |
| 218 | /** |
| 219 | * That allows to change the amount of thick for decrypting the key. |
| 220 | * |
| 221 | * @param bool - Default at this point is true - no method is selected. |
| 222 | * |
| 223 | * @since 2.0.0 |
| 224 | */ |
| 225 | $max_ticks = apply_filters( WP_2FA_PREFIX . 'totp_time_step_allowance', self::DEFAULT_TIME_STEP_ALLOWANCE ); |
| 226 | |
| 227 | // Array of all ticks to allow, sorted using absolute value to test closest match first. |
| 228 | $ticks = range( - $max_ticks, $max_ticks ); |
| 229 | usort( $ticks, array( __CLASS__, 'abssort' ) ); |
| 230 | |
| 231 | $time = time() / self::DEFAULT_TIME_STEP_SEC; |
| 232 | foreach ( $ticks as $offset ) { |
| 233 | $log_time = $time + $offset; |
| 234 | $calculdated = (string) self::calc_totp( $key, $log_time ); |
| 235 | if ( $calculdated === $authcode ) { |
| 236 | return true; |
| 237 | } |
| 238 | } |
| 239 | return false; |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * Calculate a valid code given the shared secret key |
| 244 | * |
| 245 | * @param string $key The shared secret key to use for calculating code. |
| 246 | * @param mixed $step_count The time step used to calculate the code, which is the floor of time() divided by step size. |
| 247 | * @param int $digits The number of digits in the returned code. |
| 248 | * @param string $hash The hash used to calculate the code. |
| 249 | * @param int $time_step The size of the time step. |
| 250 | * |
| 251 | * @return string The totp code |
| 252 | */ |
| 253 | public static function calc_totp( $key, $step_count = false, $digits = self::DEFAULT_DIGIT_COUNT, $hash = self::DEFAULT_CRYPTO, $time_step = self::DEFAULT_TIME_STEP_SEC ) { |
| 254 | |
| 255 | $secret = self::base32_decode( $key ); |
| 256 | |
| 257 | if ( false === $step_count ) { |
| 258 | $step_count = floor( time() / $time_step ); |
| 259 | } |
| 260 | |
| 261 | $timestamp = self::pack64( $step_count ); |
| 262 | |
| 263 | $hash = hash_hmac( $hash, $timestamp, $secret, true ); |
| 264 | |
| 265 | $offset = ord( $hash[19] ) & 0xf; |
| 266 | |
| 267 | $code = ( |
| 268 | ( ( ord( $hash[ $offset + 0 ] ) & 0x7f ) << 24 ) | |
| 269 | ( ( ord( $hash[ $offset + 1 ] ) & 0xff ) << 16 ) | |
| 270 | ( ( ord( $hash[ $offset + 2 ] ) & 0xff ) << 8 ) | |
| 271 | ( ord( $hash[ $offset + 3 ] ) & 0xff ) |
| 272 | ) % pow( 10, $digits ); |
| 273 | |
| 274 | return str_pad( $code, $digits, '0', STR_PAD_LEFT ); |
| 275 | } |
| 276 | |
| 277 | /** |
| 278 | * Decode a base32 string and return a binary representation |
| 279 | * |
| 280 | * @param string $base32_string The base 32 string to decode. |
| 281 | * |
| 282 | * @throws \Exception If string contains non-base32 characters. |
| 283 | * |
| 284 | * @return string Binary representation of decoded string |
| 285 | */ |
| 286 | public static function base32_decode( $base32_string ) { |
| 287 | |
| 288 | $base32_string = strtoupper( $base32_string ); |
| 289 | |
| 290 | if ( ! preg_match( '/^[' . self::$base_32_chars . ']+$/', $base32_string, $match ) ) { |
| 291 | throw new \Exception( 'Invalid characters in the base32 string.' ); |
| 292 | } |
| 293 | |
| 294 | $l = strlen( $base32_string ); |
| 295 | $n = 0; |
| 296 | $j = 0; |
| 297 | $binary = ''; |
| 298 | |
| 299 | for ( $i = 0; $i < $l; $i++ ) { |
| 300 | |
| 301 | $n = $n << 5; // Move buffer left by 5 to make room. |
| 302 | $n = $n + strpos( self::$base_32_chars, $base32_string[ $i ] ); // Add value into buffer. |
| 303 | $j += 5; // Keep track of number of bits in buffer. |
| 304 | |
| 305 | if ( $j >= 8 ) { |
| 306 | $j -= 8; |
| 307 | $binary .= chr( ( $n & ( 0xFF << $j ) ) >> $j ); |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | return $binary; |
| 312 | } |
| 313 | |
| 314 | /** |
| 315 | * Used with usort to sort an array by distance from 0 |
| 316 | * |
| 317 | * @param int $a First array element. |
| 318 | * @param int $b Second array element. |
| 319 | * |
| 320 | * @return int -1, 0, or 1 as needed by usort |
| 321 | */ |
| 322 | private static function abssort( $a, $b ) { |
| 323 | $a = abs( $a ); |
| 324 | $b = abs( $b ); |
| 325 | if ( $a === $b ) { |
| 326 | return 0; |
| 327 | } |
| 328 | return ( $a < $b ) ? -1 : 1; |
| 329 | } |
| 330 | |
| 331 | /** |
| 332 | * Pack stuff |
| 333 | * |
| 334 | * @param string $value The value to be packed. |
| 335 | * |
| 336 | * @return string Binary packed string. |
| 337 | */ |
| 338 | public static function pack64( $value ) { |
| 339 | // 64bit mode (PHP_INT_SIZE == 8). |
| 340 | if ( PHP_INT_SIZE >= 8 ) { |
| 341 | // If we're on PHP 5.6.3+ we can use the new 64bit pack functionality. |
| 342 | if ( version_compare( PHP_VERSION, '5.6.3', '>=' ) && PHP_INT_SIZE >= 8 ) { |
| 343 | return pack( 'J', $value ); |
| 344 | } |
| 345 | $highmap = 0xffffffff << 32; |
| 346 | $higher = ( $value & $highmap ) >> 32; |
| 347 | } else { |
| 348 | /* |
| 349 | * 32bit PHP can't shift 32 bits like that, so we have to assume 0 for the higher |
| 350 | * and not pack anything beyond it's limits. |
| 351 | */ |
| 352 | $higher = 0; |
| 353 | } |
| 354 | |
| 355 | $lowmap = 0xffffffff; |
| 356 | $lower = $value & $lowmap; |
| 357 | |
| 358 | return pack( 'NN', $higher, $lower ); |
| 359 | } |
| 360 | |
| 361 | /** |
| 362 | * Generate a random eight-digit string to send out as an auth code. |
| 363 | * |
| 364 | * @since 0.1-dev |
| 365 | * |
| 366 | * @param int $length The code length. |
| 367 | * @param string|array $chars Valid auth code characters. |
| 368 | * @return string |
| 369 | */ |
| 370 | public static function get_code( $length = 8, $chars = '1234567890' ) { |
| 371 | $code = ''; |
| 372 | if ( is_array( $chars ) ) { |
| 373 | $chars = implode( '', $chars ); |
| 374 | } |
| 375 | for ( $i = 0; $i < $length; $i++ ) { |
| 376 | $code .= substr( $chars, wp_rand( 0, strlen( $chars ) - 1 ), 1 ); |
| 377 | } |
| 378 | return $code; |
| 379 | } |
| 380 | |
| 381 | /** |
| 382 | * Generate the user token. |
| 383 | * |
| 384 | * @since 0.1-dev |
| 385 | * |
| 386 | * @param int $user_id User ID. |
| 387 | * @return string |
| 388 | */ |
| 389 | public static function generate_token( $user_id ) { |
| 390 | $token = self::get_code(); |
| 391 | |
| 392 | User_Helper::set_email_token_for_user( wp_hash( $token ), $user_id ); |
| 393 | return $token; |
| 394 | } |
| 395 | |
| 396 | /** |
| 397 | * Validate the user token. |
| 398 | * |
| 399 | * @since 0.1-dev |
| 400 | * |
| 401 | * @param \WP_User $user User ID. |
| 402 | * @param string $token User token. |
| 403 | * @return boolean |
| 404 | */ |
| 405 | public static function validate_token( $user, $token ) { |
| 406 | $user_id = $user->ID; |
| 407 | $hashed_token = self::get_user_token( $user_id ); |
| 408 | // Bail if token is empty or it doesn't match. |
| 409 | // This code is here just because people have no idea what is the difference between preaching and real life. |
| 410 | if ( empty( $hashed_token ) || ( ! hash_equals( wp_hash( $token ), $hashed_token ) ) ) { |
| 411 | self::get_login_attempts_instance()->increase_login_attempts( $user ); |
| 412 | return false; |
| 413 | } |
| 414 | |
| 415 | |
| 416 | // Ensure that the token can't be re-used. |
| 417 | self::delete_token( $user_id ); |
| 418 | self::get_login_attempts_instance()->clear_login_attempts( $user ); |
| 419 | |
| 420 | return true; |
| 421 | } |
| 422 | |
| 423 | /** |
| 424 | * Delete the user token. |
| 425 | * |
| 426 | * @since 0.1-dev |
| 427 | * |
| 428 | * @param int $user_id User ID. |
| 429 | */ |
| 430 | public static function delete_token( $user_id ) { |
| 431 | User_Helper::remove_email_token_for_user( $user_id ); |
| 432 | } |
| 433 | |
| 434 | /** |
| 435 | * Check if user has a valid token already. |
| 436 | * |
| 437 | * @param int $user_id User ID. |
| 438 | * @return boolean If user has a valid email token. |
| 439 | */ |
| 440 | public static function user_has_token( $user_id ) { |
| 441 | $hashed_token = self::get_user_token( $user_id ); |
| 442 | if ( ! empty( $hashed_token ) ) { |
| 443 | return true; |
| 444 | } else { |
| 445 | return false; |
| 446 | } |
| 447 | } |
| 448 | |
| 449 | /** |
| 450 | * Get the authentication token for the user. |
| 451 | * |
| 452 | * @param int $user_id User ID. |
| 453 | * |
| 454 | * @return string|boolean User token or `false` if no token found. |
| 455 | */ |
| 456 | public static function get_user_token( $user_id ) { |
| 457 | |
| 458 | |
| 459 | $hashed_token = User_Helper::get_email_token_for_user( $user_id ); |
| 460 | |
| 461 | if ( ! empty( $hashed_token ) && is_string( $hashed_token ) ) { |
| 462 | return $hashed_token; |
| 463 | } |
| 464 | |
| 465 | return false; |
| 466 | } |
| 467 | |
| 468 | /** |
| 469 | * Returns list of all the auth apps and their properties |
| 470 | * |
| 471 | * @return array |
| 472 | */ |
| 473 | public static function get_apps(): array { |
| 474 | return array( |
| 475 | 'authy' => array( |
| 476 | 'logo' => 'authy-logo.png', |
| 477 | 'hash' => 'authy', |
| 478 | 'name' => 'Authy', |
| 479 | ), |
| 480 | 'google' => array( |
| 481 | 'logo' => 'google-logo.png', |
| 482 | 'hash' => 'google', |
| 483 | 'name' => 'Google Authenticator', |
| 484 | ), |
| 485 | 'microsoft' => array( |
| 486 | 'logo' => 'microsoft-logo.png', |
| 487 | 'hash' => 'microsoft', |
| 488 | 'name' => 'Microsoft Authenticator', |
| 489 | ), |
| 490 | 'duo' => array( |
| 491 | 'logo' => 'duo-logo.png', |
| 492 | 'hash' => 'duo', |
| 493 | 'name' => 'Duo Security', |
| 494 | ), |
| 495 | 'lastpass' => array( |
| 496 | 'logo' => 'lastpass-logo.png', |
| 497 | 'hash' => 'lastpass', |
| 498 | 'name' => 'LastPass', |
| 499 | ), |
| 500 | 'freeotp' => array( |
| 501 | 'logo' => 'free-otp-logo.png', |
| 502 | 'hash' => 'freeotp', |
| 503 | 'name' => 'FreeOTP', |
| 504 | ), |
| 505 | 'okta' => array( |
| 506 | 'logo' => 'okta-logo.png', |
| 507 | 'hash' => 'okta', |
| 508 | 'name' => 'Okta', |
| 509 | ), |
| 510 | ); |
| 511 | } |
| 512 | |
| 513 | /** |
| 514 | * Getter for the base32 character set |
| 515 | * |
| 516 | * @return string |
| 517 | * |
| 518 | * @since 2.0.0 |
| 519 | */ |
| 520 | public static function get_base32_characters(): string { |
| 521 | return self::$base_32_chars; |
| 522 | } |
| 523 | |
| 524 | /** |
| 525 | * Validates base32 encoded string |
| 526 | * |
| 527 | * @param string $text = The text to be validated. |
| 528 | * |
| 529 | * @return boolean |
| 530 | * |
| 531 | * @since 2.0.0 |
| 532 | */ |
| 533 | public static function validate_base32_string( string $text ): bool { |
| 534 | if ( ! preg_match( '/^[' . self::$base_32_chars . ']+$/', $text, $match ) ) { |
| 535 | return false; |
| 536 | } |
| 537 | |
| 538 | return true; |
| 539 | } |
| 540 | |
| 541 | /** |
| 542 | * Checks the given key and decrypts it if necessarily |
| 543 | * |
| 544 | * @param string $key - The key to check. |
| 545 | * |
| 546 | * @return string |
| 547 | * |
| 548 | * @since 2.0.0 |
| 549 | */ |
| 550 | public static function decrypt_key_if_needed( string &$key ): string { |
| 551 | if ( '' === trim( self::$decrypted_key ) ) { |
| 552 | if ( Open_SSL::is_ssl_available() && false !== \strpos( $key, 'wps_' ) ) { |
| 553 | $key = self::$decrypted_key = Open_SSL::decrypt( substr( $key, 4 ) ); // phpcs:ignore |
| 554 | } else { |
| 555 | self::$decrypted_key = $key; |
| 556 | } |
| 557 | } |
| 558 | |
| 559 | return ( $key = self::$decrypted_key ); // phpcs:ignore |
| 560 | } |
| 561 | |
| 562 | /** |
| 563 | * Returns instance of the LoginAttempts class |
| 564 | * |
| 565 | * @return \WP2FA\Admin\Controllers\Login_Attempts |
| 566 | * |
| 567 | * @since 2.0.0 |
| 568 | */ |
| 569 | public static function get_login_attempts_instance() { |
| 570 | if ( null === self::$login_attempts ) { |
| 571 | |
| 572 | self::$login_attempts = new Login_Attempts( self::$login_num_meta_key ); |
| 573 | |
| 574 | } |
| 575 | return self::$login_attempts; |
| 576 | } |
| 577 | |
| 578 | /** |
| 579 | * Checks the number of login attempts |
| 580 | * |
| 581 | * @param \WP_User $user - The user we have to check for. |
| 582 | * |
| 583 | * @return boolean |
| 584 | * |
| 585 | * @since 2.0.0 |
| 586 | */ |
| 587 | public static function check_number_of_attempts( \WP_User $user ):bool { |
| 588 | return self::get_login_attempts_instance()->check_number_of_attempts( $user ); |
| 589 | } |
| 590 | } |
| 591 |