* @author Hans-Juergen Petrich * @copyright 2007 Jim Wigginton * @license http://www.opensource.org/licenses/mit-license.html MIT License * @link http://phpseclib.sourceforge.net */ namespace phpseclib\Crypt\Common; use phpseclib\Crypt\Hash; use phpseclib\Common\Functions\Strings; use phpseclib\Math\BigInteger; /** * Base Class for all \phpseclib\Crypt\* cipher classes * * @package Base * @author Jim Wigginton * @author Hans-Juergen Petrich */ abstract class SymmetricKey { /**#@+ * @access public * @see \phpseclib\Crypt\Common\SymmetricKey::encrypt() * @see \phpseclib\Crypt\Common\SymmetricKey::decrypt() */ /** * Encrypt / decrypt using the Counter mode. * * Set to -1 since that's what Crypt/Random.php uses to index the CTR mode. * * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Counter_.28CTR.29 */ const MODE_CTR = -1; /** * Encrypt / decrypt using the Electronic Code Book mode. * * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Electronic_codebook_.28ECB.29 */ const MODE_ECB = 1; /** * Encrypt / decrypt using the Code Book Chaining mode. * * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher-block_chaining_.28CBC.29 */ const MODE_CBC = 2; /** * Encrypt / decrypt using the Cipher Feedback mode. * * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Cipher_feedback_.28CFB.29 */ const MODE_CFB = 3; /** * Encrypt / decrypt using the Cipher Feedback mode (8bit) */ const MODE_CFB8 = 38; /** * Encrypt / decrypt using the Output Feedback mode. * * @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29 */ const MODE_OFB = 4; /** * Encrypt / decrypt using streaming mode. */ const MODE_STREAM = 5; /**#@-*/ /** * Mode Map * * @access private * @see \phpseclib\Crypt\Common\SymmetricKey::__construct() */ const MODE_MAP = [ 'ctr' => self::MODE_CTR, 'ecb' => self::MODE_ECB, 'cbc' => self::MODE_CBC, 'cfb' => self::MODE_CFB, 'cfb8' => self::MODE_CFB8, 'ofb' => self::MODE_OFB, 'stream' => self::MODE_STREAM ]; /**#@+ * @access private * @see \phpseclib\Crypt\Common\SymmetricKey::__construct() */ /** * Base value for the internal implementation $engine switch */ const ENGINE_INTERNAL = 1; /** * Base value for the eval() implementation $engine switch */ const ENGINE_EVAL = 2; /** * Base value for the mcrypt implementation $engine switch */ const ENGINE_MCRYPT = 3; /** * Base value for the mcrypt implementation $engine switch */ const ENGINE_OPENSSL = 4; /**#@-*/ /** * Engine Reverse Map * * @access private * @see \phpseclib\Crypt\Common\SymmetricKey::getEngine() */ const ENGINE_MAP = [ self::ENGINE_INTERNAL => 'PHP', self::ENGINE_EVAL => 'Eval', self::ENGINE_MCRYPT => 'mcrypt', self::ENGINE_OPENSSL => 'OpenSSL' ]; /** * The Encryption Mode * * @see self::__construct() * @var int * @access private */ protected $mode; /** * The Block Length of the block cipher * * @var int * @access private */ protected $block_size = 16; /** * The Key * * @see self::setKey() * @var string * @access private */ protected $key = false; /** * The Initialization Vector * * @see self::setIV() * @var string * @access private */ private $iv = false; /** * A "sliding" Initialization Vector * * @see self::enableContinuousBuffer() * @see self::clearBuffers() * @var string * @access private */ protected $encryptIV; /** * A "sliding" Initialization Vector * * @see self::enableContinuousBuffer() * @see self::clearBuffers() * @var string * @access private */ protected $decryptIV; /** * Continuous Buffer status * * @see self::enableContinuousBuffer() * @var bool * @access private */ protected $continuousBuffer = false; /** * Encryption buffer for CTR, OFB and CFB modes * * @see self::encrypt() * @see self::clearBuffers() * @var array * @access private */ private $enbuffer; /** * Decryption buffer for CTR, OFB and CFB modes * * @see self::decrypt() * @see self::clearBuffers() * @var array * @access private */ private $debuffer; /** * mcrypt resource for encryption * * The mcrypt resource can be recreated every time something needs to be created or it can be created just once. * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode. * * @see self::encrypt() * @var resource * @access private */ private $enmcrypt; /** * mcrypt resource for decryption * * The mcrypt resource can be recreated every time something needs to be created or it can be created just once. * Since mcrypt operates in continuous mode, by default, it'll need to be recreated when in non-continuous mode. * * @see self::decrypt() * @var resource * @access private */ private $demcrypt; /** * Does the enmcrypt resource need to be (re)initialized? * * @see \phpseclib\Crypt\Twofish::setKey() * @see \phpseclib\Crypt\Twofish::setIV() * @var bool * @access private */ private $enchanged = true; /** * Does the demcrypt resource need to be (re)initialized? * * @see \phpseclib\Crypt\Twofish::setKey() * @see \phpseclib\Crypt\Twofish::setIV() * @var bool * @access private */ private $dechanged = true; /** * mcrypt resource for CFB mode * * mcrypt's CFB mode, in (and only in) buffered context, * is broken, so phpseclib implements the CFB mode by it self, * even when the mcrypt php extension is available. * * In order to do the CFB-mode work (fast) phpseclib * use a separate ECB-mode mcrypt resource. * * @link http://phpseclib.sourceforge.net/cfb-demo.phps * @see self::encrypt() * @see self::decrypt() * @see self::setupMcrypt() * @var resource * @access private */ private $ecb; /** * Optimizing value while CFB-encrypting * * Only relevant if $continuousBuffer enabled * and $engine == self::ENGINE_MCRYPT * * It's faster to re-init $enmcrypt if * $buffer bytes > $cfb_init_len than * using the $ecb resource furthermore. * * This value depends of the chosen cipher * and the time it would be needed for it's * initialization [by mcrypt_generic_init()] * which, typically, depends on the complexity * on its internaly Key-expanding algorithm. * * @see self::encrypt() * @var int * @access private */ protected $cfb_init_len = 600; /** * Does internal cipher state need to be (re)initialized? * * @see self::setKey() * @see self::setIV() * @see self::disableContinuousBuffer() * @var bool * @access private */ protected $changed = true; /** * Padding status * * @see self::enablePadding() * @var bool * @access private */ private $padding = true; /** * Is the mode one that is paddable? * * @see self::__construct() * @var bool * @access private */ private $paddable = false; /** * Holds which crypt engine internaly should be use, * which will be determined automatically on __construct() * * Currently available $engines are: * - self::ENGINE_OPENSSL (very fast, php-extension: openssl, extension_loaded('openssl') required) * - self::ENGINE_MCRYPT (fast, php-extension: mcrypt, extension_loaded('mcrypt') required) * - self::ENGINE_EVAL (medium, pure php-engine, no php-extension required) * - self::ENGINE_INTERNAL (slower, pure php-engine, no php-extension required) * * @see self::setEngine() * @see self::encrypt() * @see self::decrypt() * @var int * @access private */ protected $engine; /** * Holds the preferred crypt engine * * @see self::setEngine() * @see self::setPreferredEngine() * @var int * @access private */ private $preferredEngine; /** * The mcrypt specific name of the cipher * * Only used if $engine == self::ENGINE_MCRYPT * * @link http://www.php.net/mcrypt_module_open * @link http://www.php.net/mcrypt_list_algorithms * @see self::setupMcrypt() * @var string * @access private */ protected $cipher_name_mcrypt; /** * The openssl specific name of the cipher * * Only used if $engine == self::ENGINE_OPENSSL * * @link http://www.php.net/openssl-get-cipher-methods * @var string * @access private */ protected $cipher_name_openssl; /** * The openssl specific name of the cipher in ECB mode * * If OpenSSL does not support the mode we're trying to use (CTR) * it can still be emulated with ECB mode. * * @link http://www.php.net/openssl-get-cipher-methods * @var string * @access private */ protected $cipher_name_openssl_ecb; /** * The default salt used by setPassword() * * @see self::setPassword() * @var string * @access private */ private $password_default_salt = 'phpseclib/salt'; /** * The name of the performance-optimized callback function * * Used by encrypt() / decrypt() * only if $engine == self::ENGINE_INTERNAL * * @see self::encrypt() * @see self::decrypt() * @see self::setupInlineCrypt() * @see self::$use_inline_crypt * @var Callback * @access private */ protected $inline_crypt; /** * Holds whether performance-optimized $inline_crypt() can/should be used. * * @see self::encrypt() * @see self::decrypt() * @see self::inline_crypt * @var mixed * @access private */ protected $use_inline_crypt; /** * If OpenSSL can be used in ECB but not in CTR we can emulate CTR * * @see self::openssl_ctr_process() * @var bool * @access private */ private $openssl_emulate_ctr = false; /** * Don't truncate / null pad key * * @see self::clearBuffers() * @var bool * @access private */ private $skip_key_adjustment = false; /** * Has the key length explicitly been set or should it be derived from the key, itself? * * @see self::setKeyLength() * @var bool * @access private */ protected $explicit_key_length = false; /** * Default Constructor. * * $mode could be: * * - ecb * * - cbc * * - ctr * * - cfb * * - ofb * * @param string $mode * @access public * @throws \InvalidArgumentException if an invalid / unsupported mode is provided */ public function __construct($mode) { $mode = strtolower($mode); // necessary because of 5.6 compatibility; we can't do isset(self::MODE_MAP[$mode]) in 5.6 $map = self::MODE_MAP; if (!isset($map[$mode])) { throw new \InvalidArgumentException('No valid mode has been specified'); } $mode = self::MODE_MAP[$mode]; // $mode dependent settings switch ($mode) { case self::MODE_ECB: case self::MODE_CBC: $this->paddable = true; break; case self::MODE_CTR: case self::MODE_CFB: case self::MODE_CFB8: case self::MODE_OFB: case self::MODE_STREAM: $this->paddable = false; break; default: throw new \InvalidArgumentException('No valid mode has been specified'); } $this->mode = $mode; } /** * Sets the initialization vector. * * setIV() is not required when self::MODE_ECB (or ie for AES: \phpseclib\Crypt\AES::MODE_ECB) is being used. * * @access public * @param string $iv * @throws \LengthException if the IV length isn't equal to the block size * @throws \InvalidArgumentException if an IV is provided when one shouldn't be * @internal Can be overwritten by a sub class, but does not have to be */ public function setIV($iv) { if ($this->mode == self::MODE_ECB) { throw new \InvalidArgumentException('This mode does not require an IV.'); } if (!$this->usesIV()) { throw new \InvalidArgumentException('This algorithm does not use an IV.'); } if (strlen($iv) != $this->block_size) { throw new \LengthException('Received initialization vector of size ' . strlen($iv) . ', but size ' . $this->block_size . ' is required'); } $this->iv = $iv; $this->changed = true; } /** * Returns whether or not the algorithm uses an IV * * @access public * @return bool */ public function usesIV() { return true; } /** * Returns the current key length in bits * * @access public * @return int */ public function getKeyLength() { return $this->key_length << 3; } /** * Returns the current block length in bits * * @access public * @return int */ public function getBlockLength() { return $this->block_size << 3; } /** * Returns the current block length in bytes * * @access public * @return int */ public function getBlockLengthInBytes() { return $this->block_size; } /** * Sets the key length. * * Keys with explicitly set lengths need to be treated accordingly * * @access public * @param int $length */ public function setKeyLength($length) { $this->explicit_key_length = $length >> 3; if (is_string($this->key) && strlen($this->key) != $this->explicit_key_length) { $this->key = false; throw new \LengthException('Key has already been set and is not ' .$this->explicit_key_length . ' bytes long'); } } /** * Sets the key. * * The min/max length(s) of the key depends on the cipher which is used. * If the key not fits the length(s) of the cipher it will paded with null bytes * up to the closest valid key length. If the key is more than max length, * we trim the excess bits. * * If the key is not explicitly set, it'll be assumed to be all null bytes. * * @access public * @param string $key * @internal Could, but not must, extend by the child Crypt_* class */ public function setKey($key) { if ($this->explicit_key_length !== false && strlen($key) != $this->explicit_key_length) { throw new \LengthException('Key length has already been set to ' . $this->explicit_key_length . ' bytes and this key is ' . strlen($key) . ' bytes'); } $this->key = $key; $this->key_length = strlen($key); $this->changed = true; $this->setEngine(); } /** * Sets the password. * * Depending on what $method is set to, setPassword()'s (optional) parameters are as follows: * {@link http://en.wikipedia.org/wiki/PBKDF2 pbkdf2} or pbkdf1: * $hash, $salt, $count, $dkLen * * Where $hash (default = sha1) currently supports the following hashes: see: Crypt/Hash.php * * @see Crypt/Hash.php * @param string $password * @param string $method * @param $func_args[] * @throws \LengthException if pbkdf1 is being used and the derived key length exceeds the hash length * @return bool * @access public * @internal Could, but not must, extend by the child Crypt_* class */ public function setPassword($password, $method = 'pbkdf2', ...$func_args) { $key = ''; $method = strtolower($method); switch ($method) { case 'pkcs12': // from https://tools.ietf.org/html/rfc7292#appendix-B.2 case 'pbkdf1': case 'pbkdf2': // Hash function $hash = isset($func_args[0]) ? strtolower($func_args[0]) : 'sha1'; $hashObj = new Hash(); $hashObj->setHash($hash); // WPA and WPA2 use the SSID as the salt $salt = isset($func_args[1]) ? $func_args[1] : $this->password_default_salt; // RFC2898#section-4.2 uses 1,000 iterations by default // WPA and WPA2 use 4,096. $count = isset($func_args[2]) ? $func_args[2] : 1000; // Keylength if (isset($func_args[3])) { $dkLen = $func_args[3]; } else { $key_length = $this->explicit_key_length !== false ? $this->explicit_key_length : $this->key_length; $dkLen = $method == 'pbkdf1' ? 2 * $key_length : $key_length; } switch (true) { case $method == 'pkcs12': /* In this specification, however, all passwords are created from BMPStrings with a NULL terminator. This means that each character in the original BMPString is encoded in 2 bytes in big-endian format (most-significant byte first). There are no Unicode byte order marks. The 2 bytes produced from the last character in the BMPString are followed by 2 additional bytes with the value 0x00. -- https://tools.ietf.org/html/rfc7292#appendix-B.1 */ $password = "\0". chunk_split($password, 1, "\0") . "\0"; /* This standard specifies 3 different values for the ID byte mentioned above: 1. If ID=1, then the pseudorandom bits being produced are to be used as key material for performing encryption or decryption. 2. If ID=2, then the pseudorandom bits being produced are to be used as an IV (Initial Value) for encryption or decryption. 3. If ID=3, then the pseudorandom bits being produced are to be used as an integrity key for MACing. */ // Construct a string, D (the "diversifier"), by concatenating v/8 // copies of ID. $blockLength = $hashObj->getBlockLengthInBytes(); $d1 = str_repeat(chr(1), $blockLength); $d2 = str_repeat(chr(2), $blockLength); $s = ''; if (strlen($salt)) { while (strlen($s) < $blockLength) { $s.= $salt; } } $s = substr($s, 0, $blockLength); $p = ''; if (strlen($password)) { while (strlen($p) < $blockLength) { $p.= $password; } } $p = substr($p, 0, $blockLength); $i = $s . $p; $this->setKey(self::pkcs12helper($dkLen, $hashObj, $i, $d1, $count)); if ($this->usesIV()) { $this->setIV(self::pkcs12helper($this->block_size, $hashObj, $i, $d2, $count)); } return true; case $method == 'pbkdf1': if ($dkLen > $hashObj->getLengthInBytes()) { throw new \LengthException('Derived key length cannot be longer than the hash length'); } $t = $password . $salt; for ($i = 0; $i < $count; ++$i) { $t = $hashObj->hash($t); } $key = substr($t, 0, $dkLen); $this->setKey(substr($key, 0, $dkLen >> 1)); if ($this->usesIV()) { $this->setIV(substr($key, $dkLen >> 1)); } return true; case !function_exists('hash_pbkdf2'): case !function_exists('hash_algos'): case !in_array($hash, hash_algos()): $i = 1; $hashObj->setKey($password); while (strlen($key) < $dkLen) { $f = $u = $hashObj->hash($salt . pack('N', $i++)); for ($j = 2; $j <= $count; ++$j) { $u = $hashObj->hash($u); $f^= $u; } $key.= $f; } $key = substr($key, 0, $dkLen); break; default: $key = hash_pbkdf2($hash, $password, $salt, $count, $dkLen, true); } break; default: throw new \InvalidArgumentException($method . ' is not a supported password hashing method'); } $this->setKey($key); return true; } /** * PKCS#12 KDF Helper Function * * As discussed here: * * {@link https://tools.ietf.org/html/rfc7292#appendix-B} * * @see self::setPassword() * @access private * @param int $n * @param \phpseclib\Crypt\Hash $hashObj * @param string $i * @param string $d * @param int $count * @return string $a */ private static function pkcs12helper($n, $hashObj, $i, $d, $count) { static $one; if (!isset($one)) { $one = new BigInteger(1); } $blockLength = $hashObj->getBlockLength() >> 3; $c = ceil($n / $hashObj->getLengthInBytes()); $a = ''; for ($j = 1; $j <= $c; $j++) { $ai = $d . $i; for ($k = 0; $k < $count; $k++) { $ai = $hashObj->hash($ai); } $b = ''; while (strlen($b) < $blockLength) { $b.= $ai; } $b = substr($b, 0, $blockLength); $b = new BigInteger($b, 256); $newi = ''; for ($k = 0; $k < strlen($i); $k+= $blockLength) { $temp = substr($i, $k, $blockLength); $temp = new BigInteger($temp, 256); $temp->setPrecision($blockLength << 3); $temp = $temp->add($b); $temp = $temp->add($one); $newi.= $temp->toBytes(false); } $i = $newi; $a.= $ai; } return substr($a, 0, $n); } /** * Encrypts a message. * * $plaintext will be padded with additional bytes such that it's length is a multiple of the block size. Other cipher * implementations may or may not pad in the same manner. Other common approaches to padding and the reasons why it's * necessary are discussed in the following * URL: * * {@link http://www.di-mgt.com.au/cryptopad.html http://www.di-mgt.com.au/cryptopad.html} * * An alternative to padding is to, separately, send the length of the file. This is what SSH, in fact, does. * strlen($plaintext) will still need to be a multiple of the block size, however, arbitrary values can be added to make it that * length. * * @see self::decrypt() * @access public * @param string $plaintext * @return string $ciphertext * @internal Could, but not must, extend by the child Crypt_* class */ public function encrypt($plaintext) { if ($this->paddable) { $plaintext = $this->pad($plaintext); } if ($this->engine === self::ENGINE_OPENSSL) { if ($this->changed) { $this->clearBuffers(); $this->changed = false; } switch ($this->mode) { case self::MODE_STREAM: return openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); case self::MODE_ECB: return openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); case self::MODE_CBC: $result = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->encryptIV); if ($this->continuousBuffer) { $this->encryptIV = substr($result, -$this->block_size); } return $result; case self::MODE_CTR: return $this->openssl_ctr_process($plaintext, $this->encryptIV, $this->enbuffer); case self::MODE_CFB: // cfb loosely routines inspired by openssl's: // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1} $ciphertext = ''; if ($this->continuousBuffer) { $iv = &$this->encryptIV; $pos = &$this->enbuffer['pos']; } else { $iv = $this->encryptIV; $pos = 0; } $len = strlen($plaintext); $i = 0; if ($pos) { $orig_pos = $pos; $max = $this->block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize $ciphertext = substr($iv, $orig_pos) ^ $plaintext; $iv = substr_replace($iv, $ciphertext, $orig_pos, $i); $plaintext = substr($plaintext, $i); } $overflow = $len % $this->block_size; if ($overflow) { $ciphertext.= openssl_encrypt(substr($plaintext, 0, -$overflow) . str_repeat("\0", $this->block_size), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv); $iv = Strings::pop($ciphertext, $this->block_size); $size = $len - $overflow; $block = $iv ^ substr($plaintext, -$overflow); $iv = substr_replace($iv, $block, 0, $overflow); $ciphertext.= $block; $pos = $overflow; } elseif ($len) { $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv); $iv = substr($ciphertext, -$this->block_size); } return $ciphertext; case self::MODE_CFB8: $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->encryptIV); if ($this->continuousBuffer) { if (($len = strlen($ciphertext)) >= $this->block_size) { $this->encryptIV = substr($ciphertext, -$this->block_size); } else { $this->encryptIV = substr($this->encryptIV, $len - $this->block_size) . substr($ciphertext, -$len); } } return $ciphertext; case self::MODE_OFB: return $this->openssl_ofb_process($plaintext, $this->encryptIV, $this->enbuffer); } } if ($this->engine === self::ENGINE_MCRYPT) { if ($this->changed) { $this->setupMcrypt(); $this->changed = false; } if ($this->enchanged) { @mcrypt_generic_init($this->enmcrypt, $this->key, $this->getIV($this->encryptIV)); $this->enchanged = false; } // re: {@link http://phpseclib.sourceforge.net/cfb-demo.phps} // using mcrypt's default handing of CFB the above would output two different things. using phpseclib's // rewritten CFB implementation the above outputs the same thing twice. if ($this->mode == self::MODE_CFB && $this->continuousBuffer) { $block_size = $this->block_size; $iv = &$this->encryptIV; $pos = &$this->enbuffer['pos']; $len = strlen($plaintext); $ciphertext = ''; $i = 0; if ($pos) { $orig_pos = $pos; $max = $block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } $ciphertext = substr($iv, $orig_pos) ^ $plaintext; $iv = substr_replace($iv, $ciphertext, $orig_pos, $i); $this->enbuffer['enmcrypt_init'] = true; } if ($len >= $block_size) { if ($this->enbuffer['enmcrypt_init'] === false || $len > $this->cfb_init_len) { if ($this->enbuffer['enmcrypt_init'] === true) { @mcrypt_generic_init($this->enmcrypt, $this->key, $iv); $this->enbuffer['enmcrypt_init'] = false; } $ciphertext.= @mcrypt_generic($this->enmcrypt, substr($plaintext, $i, $len - $len % $block_size)); $iv = substr($ciphertext, -$block_size); $len%= $block_size; } else { while ($len >= $block_size) { $iv = @mcrypt_generic($this->ecb, $iv) ^ substr($plaintext, $i, $block_size); $ciphertext.= $iv; $len-= $block_size; $i+= $block_size; } } } if ($len) { $iv = @mcrypt_generic($this->ecb, $iv); $block = $iv ^ substr($plaintext, -$len); $iv = substr_replace($iv, $block, 0, $len); $ciphertext.= $block; $pos = $len; } return $ciphertext; } $ciphertext = @mcrypt_generic($this->enmcrypt, $plaintext); if (!$this->continuousBuffer) { @mcrypt_generic_init($this->enmcrypt, $this->key, $this->getIV($this->encryptIV)); } return $ciphertext; } if ($this->changed) { $this->setup(); $this->changed = false; } if ($this->engine === self::ENGINE_EVAL) { $inline = $this->inline_crypt; return $inline('encrypt', $plaintext); } $buffer = &$this->enbuffer; $block_size = $this->block_size; $ciphertext = ''; switch ($this->mode) { case self::MODE_ECB: for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $ciphertext.= $this->encryptBlock(substr($plaintext, $i, $block_size)); } break; case self::MODE_CBC: $xor = $this->encryptIV; for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); $block = $this->encryptBlock($block ^ $xor); $xor = $block; $ciphertext.= $block; } if ($this->continuousBuffer) { $this->encryptIV = $xor; } break; case self::MODE_CTR: $xor = $this->encryptIV; if (strlen($buffer['ciphertext'])) { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); if (strlen($block) > strlen($buffer['ciphertext'])) { $buffer['ciphertext'].= $this->encryptBlock($xor); } $this->increment_str($xor); $key = Strings::shift($buffer['ciphertext'], $block_size); $ciphertext.= $block ^ $key; } } else { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); $key = $this->encryptBlock($xor); $this->increment_str($xor); $ciphertext.= $block ^ $key; } } if ($this->continuousBuffer) { $this->encryptIV = $xor; if ($start = strlen($plaintext) % $block_size) { $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext']; } } break; case self::MODE_CFB: // cfb loosely routines inspired by openssl's: // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1} if ($this->continuousBuffer) { $iv = &$this->encryptIV; $pos = &$buffer['pos']; } else { $iv = $this->encryptIV; $pos = 0; } $len = strlen($plaintext); $i = 0; if ($pos) { $orig_pos = $pos; $max = $block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize $ciphertext = substr($iv, $orig_pos) ^ $plaintext; $iv = substr_replace($iv, $ciphertext, $orig_pos, $i); } while ($len >= $block_size) { $iv = $this->encryptBlock($iv) ^ substr($plaintext, $i, $block_size); $ciphertext.= $iv; $len-= $block_size; $i+= $block_size; } if ($len) { $iv = $this->encryptBlock($iv); $block = $iv ^ substr($plaintext, $i); $iv = substr_replace($iv, $block, 0, $len); $ciphertext.= $block; $pos = $len; } break; case self::MODE_CFB8: $ciphertext = ''; $len = strlen($plaintext); $iv = $this->encryptIV; for ($i = 0; $i < $len; ++$i) { $ciphertext .= ($c = $plaintext[$i] ^ $this->encryptBlock($iv)); $iv = substr($iv, 1) . $c; } if ($this->continuousBuffer) { if ($len >= $block_size) { $this->encryptIV = substr($ciphertext, -$block_size); } else { $this->encryptIV = substr($this->encryptIV, $len - $block_size) . substr($ciphertext, -$len); } } break; case self::MODE_OFB: $xor = $this->encryptIV; if (strlen($buffer['xor'])) { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); if (strlen($block) > strlen($buffer['xor'])) { $xor = $this->encryptBlock($xor); $buffer['xor'].= $xor; } $key = Strings::shift($buffer['xor'], $block_size); $ciphertext.= $block ^ $key; } } else { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $xor = $this->encryptBlock($xor); $ciphertext.= substr($plaintext, $i, $block_size) ^ $xor; } $key = $xor; } if ($this->continuousBuffer) { $this->encryptIV = $xor; if ($start = strlen($plaintext) % $block_size) { $buffer['xor'] = substr($key, $start) . $buffer['xor']; } } break; case self::MODE_STREAM: $ciphertext = $this->encryptBlock($plaintext); break; } return $ciphertext; } /** * Decrypts a message. * * If strlen($ciphertext) is not a multiple of the block size, null bytes will be added to the end of the string until * it is. * * @see self::encrypt() * @access public * @param string $ciphertext * @return string $plaintext * @throws \LengthException if we're inside a block cipher and the ciphertext length is not a multiple of the block size * @internal Could, but not must, extend by the child Crypt_* class */ public function decrypt($ciphertext) { if ($this->paddable && strlen($ciphertext) % $this->block_size) { throw new \LengthException('The ciphertext length (' . strlen($ciphertext) . ') needs to be a multiple of the block size (' . $this->block_size . ')'); } if ($this->engine === self::ENGINE_OPENSSL) { if ($this->changed) { $this->clearBuffers(); $this->changed = false; } switch ($this->mode) { case self::MODE_STREAM: $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); break; case self::MODE_ECB: $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); break; case self::MODE_CBC: $offset = $this->block_size; $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->decryptIV); if ($this->continuousBuffer) { $this->decryptIV = substr($ciphertext, -$offset, $this->block_size); } break; case self::MODE_CTR: $plaintext = $this->openssl_ctr_process($ciphertext, $this->decryptIV, $this->debuffer); break; case self::MODE_CFB: // cfb loosely routines inspired by openssl's: // {@link http://cvs.openssl.org/fileview?f=openssl/crypto/modes/cfb128.c&v=1.3.2.2.2.1} $plaintext = ''; if ($this->continuousBuffer) { $iv = &$this->decryptIV; $pos = &$this->buffer['pos']; } else { $iv = $this->decryptIV; $pos = 0; } $len = strlen($ciphertext); $i = 0; if ($pos) { $orig_pos = $pos; $max = $this->block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $this->blocksize $plaintext = substr($iv, $orig_pos) ^ $ciphertext; $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i); $ciphertext = substr($ciphertext, $i); } $overflow = $len % $this->block_size; if ($overflow) { $plaintext.= openssl_decrypt(substr($ciphertext, 0, -$overflow), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv); if ($len - $overflow) { $iv = substr($ciphertext, -$overflow - $this->block_size, -$overflow); } $iv = openssl_encrypt(str_repeat("\0", $this->block_size), $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv); $plaintext.= $iv ^ substr($ciphertext, -$overflow); $iv = substr_replace($iv, substr($ciphertext, -$overflow), 0, $overflow); $pos = $overflow; } elseif ($len) { $plaintext.= openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $iv); $iv = substr($ciphertext, -$this->block_size); } break; case self::MODE_CFB8: $plaintext = openssl_decrypt($ciphertext, $this->cipher_name_openssl, $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->decryptIV); if ($this->continuousBuffer) { if (($len = strlen($ciphertext)) >= $this->block_size) { $this->decryptIV = substr($ciphertext, -$this->block_size); } else { $this->decryptIV = substr($this->decryptIV, $len - $this->block_size) . substr($ciphertext, -$len); } } break; case self::MODE_OFB: $plaintext = $this->openssl_ofb_process($ciphertext, $this->decryptIV, $this->debuffer); } return $this->paddable ? $this->unpad($plaintext) : $plaintext; } if ($this->engine === self::ENGINE_MCRYPT) { $block_size = $this->block_size; if ($this->changed) { $this->setupMcrypt(); $this->changed = false; } if ($this->dechanged) { @mcrypt_generic_init($this->demcrypt, $this->key, $this->getIV($this->decryptIV)); $this->dechanged = false; } if ($this->mode == self::MODE_CFB && $this->continuousBuffer) { $iv = &$this->decryptIV; $pos = &$this->debuffer['pos']; $len = strlen($ciphertext); $plaintext = ''; $i = 0; if ($pos) { $orig_pos = $pos; $max = $block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize $plaintext = substr($iv, $orig_pos) ^ $ciphertext; $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i); } if ($len >= $block_size) { $cb = substr($ciphertext, $i, $len - $len % $block_size); $plaintext.= @mcrypt_generic($this->ecb, $iv . $cb) ^ $cb; $iv = substr($cb, -$block_size); $len%= $block_size; } if ($len) { $iv = @mcrypt_generic($this->ecb, $iv); $plaintext.= $iv ^ substr($ciphertext, -$len); $iv = substr_replace($iv, substr($ciphertext, -$len), 0, $len); $pos = $len; } return $plaintext; } $plaintext = @mdecrypt_generic($this->demcrypt, $ciphertext); if (!$this->continuousBuffer) { @mcrypt_generic_init($this->demcrypt, $this->key, $this->getIV($this->decryptIV)); } return $this->paddable ? $this->unpad($plaintext) : $plaintext; } if ($this->changed) { $this->setup(); $this->changed = false; } if ($this->engine === self::ENGINE_EVAL) { $inline = $this->inline_crypt; return $inline('decrypt', $ciphertext); } $block_size = $this->block_size; $buffer = &$this->debuffer; $plaintext = ''; switch ($this->mode) { case self::MODE_ECB: for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $plaintext.= $this->decryptBlock(substr($ciphertext, $i, $block_size)); } break; case self::MODE_CBC: $xor = $this->decryptIV; for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $block = substr($ciphertext, $i, $block_size); $plaintext.= $this->decryptBlock($block) ^ $xor; $xor = $block; } if ($this->continuousBuffer) { $this->decryptIV = $xor; } break; case self::MODE_CTR: $xor = $this->decryptIV; if (strlen($buffer['ciphertext'])) { for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $block = substr($ciphertext, $i, $block_size); if (strlen($block) > strlen($buffer['ciphertext'])) { $buffer['ciphertext'].= $this->encryptBlock($xor); } $this->increment_str($xor); $key = Strings::shift($buffer['ciphertext'], $block_size); $plaintext.= $block ^ $key; } } else { for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $block = substr($ciphertext, $i, $block_size); $key = $this->encryptBlock($xor); $this->increment_str($xor); $plaintext.= $block ^ $key; } } if ($this->continuousBuffer) { $this->decryptIV = $xor; if ($start = strlen($ciphertext) % $block_size) { $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext']; } } break; case self::MODE_CFB: if ($this->continuousBuffer) { $iv = &$this->decryptIV; $pos = &$buffer['pos']; } else { $iv = $this->decryptIV; $pos = 0; } $len = strlen($ciphertext); $i = 0; if ($pos) { $orig_pos = $pos; $max = $block_size - $pos; if ($len >= $max) { $i = $max; $len-= $max; $pos = 0; } else { $i = $len; $pos+= $len; $len = 0; } // ie. $i = min($max, $len), $len-= $i, $pos+= $i, $pos%= $blocksize $plaintext = substr($iv, $orig_pos) ^ $ciphertext; $iv = substr_replace($iv, substr($ciphertext, 0, $i), $orig_pos, $i); } while ($len >= $block_size) { $iv = $this->encryptBlock($iv); $cb = substr($ciphertext, $i, $block_size); $plaintext.= $iv ^ $cb; $iv = $cb; $len-= $block_size; $i+= $block_size; } if ($len) { $iv = $this->encryptBlock($iv); $plaintext.= $iv ^ substr($ciphertext, $i); $iv = substr_replace($iv, substr($ciphertext, $i), 0, $len); $pos = $len; } break; case self::MODE_CFB8: $plaintext = ''; $len = strlen($ciphertext); $iv = $this->decryptIV; for ($i = 0; $i < $len; ++$i) { $plaintext .= $ciphertext[$i] ^ $this->encryptBlock($iv); $iv = substr($iv, 1) . $ciphertext[$i]; } if ($this->continuousBuffer) { if ($len >= $block_size) { $this->decryptIV = substr($ciphertext, -$block_size); } else { $this->decryptIV = substr($this->decryptIV, $len - $block_size) . substr($ciphertext, -$len); } } break; case self::MODE_OFB: $xor = $this->decryptIV; if (strlen($buffer['xor'])) { for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $block = substr($ciphertext, $i, $block_size); if (strlen($block) > strlen($buffer['xor'])) { $xor = $this->encryptBlock($xor); $buffer['xor'].= $xor; } $key = Strings::shift($buffer['xor'], $block_size); $plaintext.= $block ^ $key; } } else { for ($i = 0; $i < strlen($ciphertext); $i+=$block_size) { $xor = $this->encryptBlock($xor); $plaintext.= substr($ciphertext, $i, $block_size) ^ $xor; } $key = $xor; } if ($this->continuousBuffer) { $this->decryptIV = $xor; if ($start = strlen($ciphertext) % $block_size) { $buffer['xor'] = substr($key, $start) . $buffer['xor']; } } break; case self::MODE_STREAM: $plaintext = $this->decryptBlock($ciphertext); break; } return $this->paddable ? $this->unpad($plaintext) : $plaintext; } /** * Get the IV * * mcrypt requires an IV even if ECB is used * * @see self::encrypt() * @see self::decrypt() * @param string $iv * @return string * @access private */ public function getIV($iv) { return $this->mode == self::MODE_ECB ? str_repeat("\0", $this->block_size) : $iv; } /** * OpenSSL CTR Processor * * PHP's OpenSSL bindings do not operate in continuous mode so we'll wrap around it. Since the keystream * for CTR is the same for both encrypting and decrypting this function is re-used by both SymmetricKey::encrypt() * and SymmetricKey::decrypt(). Also, OpenSSL doesn't implement CTR for all of it's symmetric ciphers so this * function will emulate CTR with ECB when necessary. * * @see self::encrypt() * @see self::decrypt() * @param string $plaintext * @param string $encryptIV * @param array $buffer * @return string * @access private */ private function openssl_ctr_process($plaintext, &$encryptIV, &$buffer) { $ciphertext = ''; $block_size = $this->block_size; $key = $this->key; if ($this->openssl_emulate_ctr) { $xor = $encryptIV; if (strlen($buffer['ciphertext'])) { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); if (strlen($block) > strlen($buffer['ciphertext'])) { $buffer['ciphertext'].= openssl_encrypt($xor, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); } $this->increment_str($xor); $otp = Strings::shift($buffer['ciphertext'], $block_size); $ciphertext.= $block ^ $otp; } } else { for ($i = 0; $i < strlen($plaintext); $i+=$block_size) { $block = substr($plaintext, $i, $block_size); $otp = openssl_encrypt($xor, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); $this->increment_str($xor); $ciphertext.= $block ^ $otp; } } if ($this->continuousBuffer) { $encryptIV = $xor; if ($start = strlen($plaintext) % $block_size) { $buffer['ciphertext'] = substr($key, $start) . $buffer['ciphertext']; } } return $ciphertext; } if (strlen($buffer['ciphertext'])) { $ciphertext = $plaintext ^ Strings::shift($buffer['ciphertext'], strlen($plaintext)); $plaintext = substr($plaintext, strlen($ciphertext)); if (!strlen($plaintext)) { return $ciphertext; } } $overflow = strlen($plaintext) % $block_size; if ($overflow) { $plaintext2 = Strings::pop($plaintext, $overflow); // ie. trim $plaintext to a multiple of $block_size and put rest of $plaintext in $plaintext2 $encrypted = openssl_encrypt($plaintext . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV); $temp = Strings::pop($encrypted, $block_size); $ciphertext.= $encrypted . ($plaintext2 ^ $temp); if ($this->continuousBuffer) { $buffer['ciphertext'] = substr($temp, $overflow); $encryptIV = $temp; } } elseif (!strlen($buffer['ciphertext'])) { $ciphertext.= openssl_encrypt($plaintext . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV); $temp = Strings::pop($ciphertext, $block_size); if ($this->continuousBuffer) { $encryptIV = $temp; } } if ($this->continuousBuffer) { $encryptIV = openssl_decrypt($encryptIV, $this->cipher_name_openssl_ecb, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); if ($overflow) { $this->increment_str($encryptIV); } } return $ciphertext; } /** * OpenSSL OFB Processor * * PHP's OpenSSL bindings do not operate in continuous mode so we'll wrap around it. Since the keystream * for OFB is the same for both encrypting and decrypting this function is re-used by both SymmetricKey::encrypt() * and SymmetricKey::decrypt(). * * @see self::encrypt() * @see self::decrypt() * @param string $plaintext * @param string $encryptIV * @param array $buffer * @return string * @access private */ private function openssl_ofb_process($plaintext, &$encryptIV, &$buffer) { if (strlen($buffer['xor'])) { $ciphertext = $plaintext ^ $buffer['xor']; $buffer['xor'] = substr($buffer['xor'], strlen($ciphertext)); $plaintext = substr($plaintext, strlen($ciphertext)); } else { $ciphertext = ''; } $block_size = $this->block_size; $len = strlen($plaintext); $key = $this->key; $overflow = $len % $block_size; if (strlen($plaintext)) { if ($overflow) { $ciphertext.= openssl_encrypt(substr($plaintext, 0, -$overflow) . str_repeat("\0", $block_size), $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV); $xor = Strings::pop($ciphertext, $block_size); if ($this->continuousBuffer) { $encryptIV = $xor; } $ciphertext.= Strings::shift($xor, $overflow) ^ substr($plaintext, -$overflow); if ($this->continuousBuffer) { $buffer['xor'] = $xor; } } else { $ciphertext = openssl_encrypt($plaintext, $this->cipher_name_openssl, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $encryptIV); if ($this->continuousBuffer) { $encryptIV = substr($ciphertext, -$block_size) ^ substr($plaintext, -$block_size); } } } return $ciphertext; } /** * phpseclib <-> OpenSSL Mode Mapper * * May need to be overwritten by classes extending this one in some cases * * @return string * @access private */ protected function openssl_translate_mode() { switch ($this->mode) { case self::MODE_ECB: return 'ecb'; case self::MODE_CBC: return 'cbc'; case self::MODE_CTR: return 'ctr'; case self::MODE_CFB: return 'cfb'; case self::MODE_CFB8: return 'cfb8'; case self::MODE_OFB: return 'ofb'; } } /** * Pad "packets". * * Block ciphers working by encrypting between their specified [$this->]block_size at a time * If you ever need to encrypt or decrypt something that isn't of the proper length, it becomes necessary to * pad the input so that it is of the proper length. * * Padding is enabled by default. Sometimes, however, it is undesirable to pad strings. Such is the case in SSH, * where "packets" are padded with random bytes before being encrypted. Unpad these packets and you risk stripping * away characters that shouldn't be stripped away. (SSH knows how many bytes are added because the length is * transmitted separately) * * @see self::disablePadding() * @access public */ public function enablePadding() { $this->padding = true; } /** * Do not pad packets. * * @see self::enablePadding() * @access public */ public function disablePadding() { $this->padding = false; } /** * Treat consecutive "packets" as if they are a continuous buffer. * * Say you have a 32-byte plaintext $plaintext. Using the default behavior, the two following code snippets * will yield different outputs: * * * echo $rijndael->encrypt(substr($plaintext, 0, 16)); * echo $rijndael->encrypt(substr($plaintext, 16, 16)); * * * echo $rijndael->encrypt($plaintext); * * * The solution is to enable the continuous buffer. Although this will resolve the above discrepancy, it creates * another, as demonstrated with the following: * * * $rijndael->encrypt(substr($plaintext, 0, 16)); * echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16))); * * * echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16))); * * * With the continuous buffer disabled, these would yield the same output. With it enabled, they yield different * outputs. The reason is due to the fact that the initialization vector's change after every encryption / * decryption round when the continuous buffer is enabled. When it's disabled, they remain constant. * * Put another way, when the continuous buffer is enabled, the state of the \phpseclib\Crypt\*() object changes after each * encryption / decryption round, whereas otherwise, it'd remain constant. For this reason, it's recommended that * continuous buffers not be used. They do offer better security and are, in fact, sometimes required (SSH uses them), * however, they are also less intuitive and more likely to cause you problems. * * @see self::disableContinuousBuffer() * @access public * @internal Could, but not must, extend by the child Crypt_* class */ public function enableContinuousBuffer() { if ($this->mode == self::MODE_ECB) { return; } $this->continuousBuffer = true; $this->setEngine(); } /** * Treat consecutive packets as if they are a discontinuous buffer. * * The default behavior. * * @see self::enableContinuousBuffer() * @access public * @internal Could, but not must, extend by the child Crypt_* class */ public function disableContinuousBuffer() { if ($this->mode == self::MODE_ECB) { return; } if (!$this->continuousBuffer) { return; } $this->continuousBuffer = false; $this->changed = true; $this->setEngine(); } /** * Test for engine validity * * @see self::__construct() * @param int $engine * @access private * @return bool */ protected function isValidEngineHelper($engine) { switch ($engine) { case self::ENGINE_OPENSSL: if ($this->mode == self::MODE_STREAM && $this->continuousBuffer) { return false; } $this->openssl_emulate_ctr = false; $result = $this->cipher_name_openssl && extension_loaded('openssl'); if (!$result) { return false; } $methods = openssl_get_cipher_methods(); if (in_array($this->cipher_name_openssl, $methods)) { return true; } // not all of openssl's symmetric cipher's support ctr. for those // that don't we'll emulate it switch ($this->mode) { case self::MODE_CTR: if (in_array($this->cipher_name_openssl_ecb, $methods)) { $this->openssl_emulate_ctr = true; return true; } } return false; case self::ENGINE_MCRYPT: return $this->cipher_name_mcrypt && extension_loaded('mcrypt') && in_array($this->cipher_name_mcrypt, @mcrypt_list_algorithms()); case self::ENGINE_EVAL: return method_exists($this, 'setupInlineCrypt'); case self::ENGINE_INTERNAL: return true; } return false; } /** * Test for engine validity * * @see self::__construct() * @param string $engine * @access public * @return bool */ public function isValidEngine($engine) { static $reverseMap; if (!isset($reverseMap)) { $reverseMap = array_map('strtolower', self::ENGINE_MAP); $reverseMap = array_flip($reverseMap); } $engine = strtolower($engine); if (!isset($reverseMap[$engine])) { return false; } return $this->isValidEngineHelper($reverseMap[$engine]); } /** * Sets the preferred crypt engine * * Currently, $engine could be: * * - OpenSSL [very fast] * * - mcrypt [fast] * * - Eval [slow] * * - PHP [slowest] * * If the preferred crypt engine is not available the fastest available one will be used * * @see self::__construct() * @param string $engine * @access public */ public function setPreferredEngine($engine) { static $reverseMap; if (!isset($reverseMap)) { $reverseMap = array_map('strtolower', self::ENGINE_MAP); $reverseMap = array_flip($reverseMap); } $engine = strtolower($engine); $this->preferredEngine = isset($reverseMap[$engine]) ? $reverseMap[$engine] : self::ENGINE_OPENSSL; $this->setEngine(); } /** * Returns the engine currently being utilized * * @see self::setEngine() * @access public */ public function getEngine() { return self::ENGINE_MAP[$this->engine]; } /** * Sets the engine as appropriate * * @see self::__construct() * @access private */ protected function setEngine() { $this->engine = null; $candidateEngines = [ $this->preferredEngine, self::ENGINE_OPENSSL, self::ENGINE_MCRYPT, self::ENGINE_EVAL ]; foreach ($candidateEngines as $engine) { if ($this->isValidEngineHelper($engine)) { $this->engine = $engine; break; } } if (!$this->engine) { $this->engine = self::ENGINE_INTERNAL; } if ($this->engine != self::ENGINE_MCRYPT && $this->enmcrypt) { // Closing the current mcrypt resource(s). _mcryptSetup() will, if needed, // (re)open them with the module named in $this->cipher_name_mcrypt @mcrypt_module_close($this->enmcrypt); @mcrypt_module_close($this->demcrypt); $this->enmcrypt = null; $this->demcrypt = null; if ($this->ecb) { @mcrypt_module_close($this->ecb); $this->ecb = null; } } $this->changed = true; } /** * Encrypts a block * * Note: Must be extended by the child \phpseclib\Crypt\* class * * @access private * @param string $in * @return string */ abstract protected function encryptBlock($in); /** * Decrypts a block * * Note: Must be extended by the child \phpseclib\Crypt\* class * * @access private * @param string $in * @return string */ abstract protected function decryptBlock($in); /** * Setup the key (expansion) * * Only used if $engine == self::ENGINE_INTERNAL * * Note: Must extend by the child \phpseclib\Crypt\* class * * @see self::setup() * @access private */ abstract protected function setupKey(); /** * Setup the self::ENGINE_INTERNAL $engine * * (re)init, if necessary, the internal cipher $engine and flush all $buffers * Used (only) if $engine == self::ENGINE_INTERNAL * * _setup() will be called each time if $changed === true * typically this happens when using one or more of following public methods: * * - setKey() * * - setIV() * * - disableContinuousBuffer() * * - First run of encrypt() / decrypt() with no init-settings * * @see self::setKey() * @see self::setIV() * @see self::disableContinuousBuffer() * @access private * @internal setup() is always called before en/decryption. * @internal Could, but not must, extend by the child Crypt_* class */ protected function setup() { $this->clearBuffers(); $this->setupKey(); if ($this->engine === self::ENGINE_EVAL) { $this->setupInlineCrypt(); } } /** * Setup the self::ENGINE_MCRYPT $engine * * (re)init, if necessary, the (ext)mcrypt resources and flush all $buffers * Used (only) if $engine = self::ENGINE_MCRYPT * * _setupMcrypt() will be called each time if $changed === true * typically this happens when using one or more of following public methods: * * - setKey() * * - setIV() * * - disableContinuousBuffer() * * - First run of encrypt() / decrypt() * * @see self::setKey() * @see self::setIV() * @see self::disableContinuousBuffer() * @access private * @internal Could, but not must, extend by the child Crypt_* class */ private function setupMcrypt() { $this->clearBuffers(); $this->enchanged = $this->dechanged = true; if (!isset($this->enmcrypt)) { static $mcrypt_modes = [ self::MODE_CTR => 'ctr', self::MODE_ECB => MCRYPT_MODE_ECB, self::MODE_CBC => MCRYPT_MODE_CBC, self::MODE_CFB => 'ncfb', self::MODE_CFB8 => MCRYPT_MODE_CFB, self::MODE_OFB => MCRYPT_MODE_NOFB, self::MODE_STREAM => MCRYPT_MODE_STREAM, ]; $this->demcrypt = @mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], ''); $this->enmcrypt = @mcrypt_module_open($this->cipher_name_mcrypt, '', $mcrypt_modes[$this->mode], ''); // we need the $ecb mcrypt resource (only) in MODE_CFB with enableContinuousBuffer() // to workaround mcrypt's broken ncfb implementation in buffered mode // see: {@link http://phpseclib.sourceforge.net/cfb-demo.phps} if ($this->mode == self::MODE_CFB) { $this->ecb = @mcrypt_module_open($this->cipher_name_mcrypt, '', MCRYPT_MODE_ECB, ''); } } // else should mcrypt_generic_deinit be called? if ($this->mode == self::MODE_CFB) { @mcrypt_generic_init($this->ecb, $this->key, str_repeat("\0", $this->block_size)); } } /** * Pads a string * * Pads a string using the RSA PKCS padding standards so that its length is a multiple of the blocksize. * $this->block_size - (strlen($text) % $this->block_size) bytes are added, each of which is equal to * chr($this->block_size - (strlen($text) % $this->block_size) * * If padding is disabled and $text is not a multiple of the blocksize, the string will be padded regardless * and padding will, hence forth, be enabled. * * @see self::unpad() * @param string $text * @throws \LengthException if padding is disabled and the plaintext's length is not a multiple of the block size * @access private * @return string */ protected function pad($text) { $length = strlen($text); if (!$this->padding) { if ($length % $this->block_size == 0) { return $text; } else { throw new \LengthException("The plaintext's length ($length) is not a multiple of the block size ({$this->block_size}). Try enabling padding."); } } $pad = $this->block_size - ($length % $this->block_size); return str_pad($text, $length + $pad, chr($pad)); } /** * Unpads a string. * * If padding is enabled and the reported padding length is invalid the encryption key will be assumed to be wrong * and false will be returned. * * @see self::pad() * @param string $text * @throws \LengthException if the ciphertext's length is not a multiple of the block size * @access private * @return string */ protected function unpad($text) { if (!$this->padding) { return $text; } $length = ord($text[strlen($text) - 1]); if (!$length || $length > $this->block_size) { throw new \LengthException("The ciphertext has an invalid padding length ($length) compared to the block size ({$this->block_size})"); } return substr($text, 0, -$length); } /** * Clears internal buffers * * Clearing/resetting the internal buffers is done everytime * after disableContinuousBuffer() or on cipher $engine (re)init * ie after setKey() or setIV() * * @access private * @internal Could, but not must, extend by the child Crypt_* class * @throws \UnexpectedValueException when an IV is required but not defined */ private function clearBuffers() { $this->enbuffer = $this->debuffer = ['ciphertext' => '', 'xor' => '', 'pos' => 0, 'enmcrypt_init' => true]; if ($this->iv === false && !in_array($this->mode, [self::MODE_STREAM, self::MODE_ECB])) { throw new \UnexpectedValueException('No IV has been defined'); } $this->encryptIV = $this->decryptIV = $this->iv; } /** * Increment the current string * * @see self::decrypt() * @see self::encrypt() * @param string $var * @access private */ protected function increment_str(&$var) { for ($i = 4; $i <= strlen($var); $i+= 4) { $temp = substr($var, -$i, 4); switch ($temp) { case "\xFF\xFF\xFF\xFF": $var = substr_replace($var, "\x00\x00\x00\x00", -$i, 4); break; case "\x7F\xFF\xFF\xFF": $var = substr_replace($var, "\x80\x00\x00\x00", -$i, 4); return; default: $temp = unpack('Nnum', $temp); $var = substr_replace($var, pack('N', $temp['num'] + 1), -$i, 4); return; } } $remainder = strlen($var) % 4; if ($remainder == 0) { return; } $temp = unpack('Nnum', str_pad(substr($var, 0, $remainder), 4, "\0", STR_PAD_LEFT)); $temp = substr(pack('N', $temp['num'] + 1), -$remainder); $var = substr_replace($var, $temp, 0, $remainder); } /** * Setup the performance-optimized function for de/encrypt() * * Stores the created (or existing) callback function-name * in $this->inline_crypt * * Internally for phpseclib developers: * * _setupInlineCrypt() would be called only if: * * - $this->engine === self::ENGINE_EVAL * * - each time on _setup(), after(!) _setupKey() * * * This ensures that _setupInlineCrypt() has always a * full ready2go initializated internal cipher $engine state * where, for example, the keys already expanded, * keys/block_size calculated and such. * * It is, each time if called, the responsibility of _setupInlineCrypt(): * * - to set $this->inline_crypt to a valid and fully working callback function * as a (faster) replacement for encrypt() / decrypt() * * - NOT to create unlimited callback functions (for memory reasons!) * no matter how often _setupInlineCrypt() would be called. At some * point of amount they must be generic re-useable. * * - the code of _setupInlineCrypt() it self, * and the generated callback code, * must be, in following order: * - 100% safe * - 100% compatible to encrypt()/decrypt() * - using only php5+ features/lang-constructs/php-extensions if * compatibility (down to php4) or fallback is provided * - readable/maintainable/understandable/commented and... not-cryptic-styled-code :-) * - >= 10% faster than encrypt()/decrypt() [which is, by the way, * the reason for the existence of _setupInlineCrypt() :-)] * - memory-nice * - short (as good as possible) * * Note: - _setupInlineCrypt() is using _createInlineCryptFunction() to create the full callback function code. * - In case of using inline crypting, _setupInlineCrypt() must extend by the child \phpseclib\Crypt\* class. * - The following variable names are reserved: * - $_* (all variable names prefixed with an underscore) * - $self (object reference to it self. Do not use $this, but $self instead) * - $in (the content of $in has to en/decrypt by the generated code) * - The callback function should not use the 'return' statement, but en/decrypt'ing the content of $in only * * * @see self::setup() * @see self::createInlineCryptFunction() * @see self::encrypt() * @see self::decrypt() * @access private * @internal If a Crypt_* class providing inline crypting it must extend _setupInlineCrypt() */ //protected function setupInlineCrypt(); /** * Creates the performance-optimized function for en/decrypt() * * Internally for phpseclib developers: * * _createInlineCryptFunction(): * * - merge the $cipher_code [setup'ed by _setupInlineCrypt()] * with the current [$this->]mode of operation code * * - create the $inline function, which called by encrypt() / decrypt() * as its replacement to speed up the en/decryption operations. * * - return the name of the created $inline callback function * * - used to speed up en/decryption * * * * The main reason why can speed up things [up to 50%] this way are: * * - using variables more effective then regular. * (ie no use of expensive arrays but integers $k_0, $k_1 ... * or even, for example, the pure $key[] values hardcoded) * * - avoiding 1000's of function calls of ie _encryptBlock() * but inlining the crypt operations. * in the mode of operation for() loop. * * - full loop unroll the (sometimes key-dependent) rounds * avoiding this way ++$i counters and runtime-if's etc... * * The basic code architectur of the generated $inline en/decrypt() * lambda function, in pseudo php, is: * * * +----------------------------------------------------------------------------------------------+ * | callback $inline = create_function: | * | lambda_function_0001_crypt_ECB($action, $text) | * | { | * | INSERT PHP CODE OF: | * | $cipher_code['init_crypt']; // general init code. | * | // ie: $sbox'es declarations used for | * | // encrypt and decrypt'ing. | * | | * | switch ($action) { | * | case 'encrypt': | * | INSERT PHP CODE OF: | * | $cipher_code['init_encrypt']; // encrypt sepcific init code. | * | ie: specified $key or $box | * | declarations for encrypt'ing. | * | | * | foreach ($ciphertext) { | * | $in = $block_size of $ciphertext; | * | | * | INSERT PHP CODE OF: | * | $cipher_code['encrypt_block']; // encrypt's (string) $in, which is always: | * | // strlen($in) == $this->block_size | * | // here comes the cipher algorithm in action | * | // for encryption. | * | // $cipher_code['encrypt_block'] has to | * | // encrypt the content of the $in variable | * | | * | $plaintext .= $in; | * | } | * | return $plaintext; | * | | * | case 'decrypt': | * | INSERT PHP CODE OF: | * | $cipher_code['init_decrypt']; // decrypt sepcific init code | * | ie: specified $key or $box | * | declarations for decrypt'ing. | * | foreach ($plaintext) { | * | $in = $block_size of $plaintext; | * | | * | INSERT PHP CODE OF: | * | $cipher_code['decrypt_block']; // decrypt's (string) $in, which is always | * | // strlen($in) == $this->block_size | * | // here comes the cipher algorithm in action | * | // for decryption. | * | // $cipher_code['decrypt_block'] has to | * | // decrypt the content of the $in variable | * | $ciphertext .= $in; | * | } | * | return $ciphertext; | * | } | * | } | * +----------------------------------------------------------------------------------------------+ * * * See also the \phpseclib\Crypt\*::_setupInlineCrypt()'s for * productive inline $cipher_code's how they works. * * Structure of: * * $cipher_code = [ * 'init_crypt' => (string) '', // optional * 'init_encrypt' => (string) '', // optional * 'init_decrypt' => (string) '', // optional * 'encrypt_block' => (string) '', // required * 'decrypt_block' => (string) '' // required * ]; * * * @see self::setupInlineCrypt() * @see self::encrypt() * @see self::decrypt() * @param array $cipher_code * @access private * @return string (the name of the created callback function) */ protected function createInlineCryptFunction($cipher_code) { $block_size = $this->block_size; // optional $init_crypt = isset($cipher_code['init_crypt']) ? $cipher_code['init_crypt'] : ''; $init_encrypt = isset($cipher_code['init_encrypt']) ? $cipher_code['init_encrypt'] : ''; $init_decrypt = isset($cipher_code['init_decrypt']) ? $cipher_code['init_decrypt'] : ''; // required $encrypt_block = $cipher_code['encrypt_block']; $decrypt_block = $cipher_code['decrypt_block']; // Generating mode of operation inline code, // merged with the $cipher_code algorithm // for encrypt- and decryption. switch ($this->mode) { case self::MODE_ECB: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_plaintext_len = strlen($_text); for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $in = substr($_text, $_i, '.$block_size.'); '.$encrypt_block.' $_ciphertext.= $in; } return $_ciphertext; '; $decrypt = $init_decrypt . ' $_plaintext = ""; $_text = str_pad($_text, strlen($_text) + ('.$block_size.' - strlen($_text) % '.$block_size.') % '.$block_size.', chr(0)); $_ciphertext_len = strlen($_text); for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $in = substr($_text, $_i, '.$block_size.'); '.$decrypt_block.' $_plaintext.= $in; } return $this->unpad($_plaintext); '; break; case self::MODE_CTR: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_plaintext_len = strlen($_text); $_xor = $this->encryptIV; $_buffer = &$this->enbuffer; if (strlen($_buffer["ciphertext"])) { for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); if (strlen($_block) > strlen($_buffer["ciphertext"])) { $in = $_xor; '.$encrypt_block.' $this->increment_str($_xor); $_buffer["ciphertext"].= $in; } $_key = \phpseclib\Common\Functions\Strings::shift($_buffer["ciphertext"], '.$block_size.'); $_ciphertext.= $_block ^ $_key; } } else { for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); $in = $_xor; '.$encrypt_block.' $this->increment_str($_xor); $_key = $in; $_ciphertext.= $_block ^ $_key; } } if ($this->continuousBuffer) { $this->encryptIV = $_xor; if ($_start = $_plaintext_len % '.$block_size.') { $_buffer["ciphertext"] = substr($_key, $_start) . $_buffer["ciphertext"]; } } return $_ciphertext; '; $decrypt = $init_encrypt . ' $_plaintext = ""; $_ciphertext_len = strlen($_text); $_xor = $this->decryptIV; $_buffer = &$this->debuffer; if (strlen($_buffer["ciphertext"])) { for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); if (strlen($_block) > strlen($_buffer["ciphertext"])) { $in = $_xor; '.$encrypt_block.' $this->increment_str($_xor); $_buffer["ciphertext"].= $in; } $_key = \phpseclib\Common\Functions\Strings::shift($_buffer["ciphertext"], '.$block_size.'); $_plaintext.= $_block ^ $_key; } } else { for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); $in = $_xor; '.$encrypt_block.' $this->increment_str($_xor); $_key = $in; $_plaintext.= $_block ^ $_key; } } if ($this->continuousBuffer) { $this->decryptIV = $_xor; if ($_start = $_ciphertext_len % '.$block_size.') { $_buffer["ciphertext"] = substr($_key, $_start) . $_buffer["ciphertext"]; } } return $_plaintext; '; break; case self::MODE_CFB: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_buffer = &$this->enbuffer; if ($this->continuousBuffer) { $_iv = &$this->encryptIV; $_pos = &$_buffer["pos"]; } else { $_iv = $this->encryptIV; $_pos = 0; } $_len = strlen($_text); $_i = 0; if ($_pos) { $_orig_pos = $_pos; $_max = '.$block_size.' - $_pos; if ($_len >= $_max) { $_i = $_max; $_len-= $_max; $_pos = 0; } else { $_i = $_len; $_pos+= $_len; $_len = 0; } $_ciphertext = substr($_iv, $_orig_pos) ^ $_text; $_iv = substr_replace($_iv, $_ciphertext, $_orig_pos, $_i); } while ($_len >= '.$block_size.') { $in = $_iv; '.$encrypt_block.'; $_iv = $in ^ substr($_text, $_i, '.$block_size.'); $_ciphertext.= $_iv; $_len-= '.$block_size.'; $_i+= '.$block_size.'; } if ($_len) { $in = $_iv; '.$encrypt_block.' $_iv = $in; $_block = $_iv ^ substr($_text, $_i); $_iv = substr_replace($_iv, $_block, 0, $_len); $_ciphertext.= $_block; $_pos = $_len; } return $_ciphertext; '; $decrypt = $init_encrypt . ' $_plaintext = ""; $_buffer = &$this->debuffer; if ($this->continuousBuffer) { $_iv = &$this->decryptIV; $_pos = &$_buffer["pos"]; } else { $_iv = $this->decryptIV; $_pos = 0; } $_len = strlen($_text); $_i = 0; if ($_pos) { $_orig_pos = $_pos; $_max = '.$block_size.' - $_pos; if ($_len >= $_max) { $_i = $_max; $_len-= $_max; $_pos = 0; } else { $_i = $_len; $_pos+= $_len; $_len = 0; } $_plaintext = substr($_iv, $_orig_pos) ^ $_text; $_iv = substr_replace($_iv, substr($_text, 0, $_i), $_orig_pos, $_i); } while ($_len >= '.$block_size.') { $in = $_iv; '.$encrypt_block.' $_iv = $in; $cb = substr($_text, $_i, '.$block_size.'); $_plaintext.= $_iv ^ $cb; $_iv = $cb; $_len-= '.$block_size.'; $_i+= '.$block_size.'; } if ($_len) { $in = $_iv; '.$encrypt_block.' $_iv = $in; $_plaintext.= $_iv ^ substr($_text, $_i); $_iv = substr_replace($_iv, substr($_text, $_i), 0, $_len); $_pos = $_len; } return $_plaintext; '; break; case self::MODE_CFB8: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_len = strlen($_text); $_iv = $this->encryptIV; for ($_i = 0; $_i < $_len; ++$_i) { $in = $_iv; '.$encrypt_block.' $_ciphertext .= ($_c = $_text[$_i] ^ $in); $_iv = substr($_iv, 1) . $_c; } if ($this->continuousBuffer) { if ($_len >= '.$block_size.') { $this->encryptIV = substr($_ciphertext, -'.$block_size.'); } else { $this->encryptIV = substr($this->encryptIV, $_len - '.$block_size.') . substr($_ciphertext, -$_len); } } return $_ciphertext; '; $decrypt = $init_encrypt . ' $_plaintext = ""; $_len = strlen($_text); $_iv = $this->decryptIV; for ($_i = 0; $_i < $_len; ++$_i) { $in = $_iv; '.$encrypt_block.' $_plaintext .= $_text[$_i] ^ $in; $_iv = substr($_iv, 1) . $_text[$_i]; } if ($this->continuousBuffer) { if ($_len >= '.$block_size.') { $this->decryptIV = substr($_text, -'.$block_size.'); } else { $this->decryptIV = substr($this->decryptIV, $_len - '.$block_size.') . substr($_text, -$_len); } } return $_plaintext; '; break; case self::MODE_OFB: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_plaintext_len = strlen($_text); $_xor = $this->encryptIV; $_buffer = &$this->enbuffer; if (strlen($_buffer["xor"])) { for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); if (strlen($_block) > strlen($_buffer["xor"])) { $in = $_xor; '.$encrypt_block.' $_xor = $in; $_buffer["xor"].= $_xor; } $_key = \phpseclib\Common\Functions\Strings::shift($_buffer["xor"], '.$block_size.'); $_ciphertext.= $_block ^ $_key; } } else { for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $in = $_xor; '.$encrypt_block.' $_xor = $in; $_ciphertext.= substr($_text, $_i, '.$block_size.') ^ $_xor; } $_key = $_xor; } if ($this->continuousBuffer) { $this->encryptIV = $_xor; if ($_start = $_plaintext_len % '.$block_size.') { $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"]; } } return $_ciphertext; '; $decrypt = $init_encrypt . ' $_plaintext = ""; $_ciphertext_len = strlen($_text); $_xor = $this->decryptIV; $_buffer = &$this->debuffer; if (strlen($_buffer["xor"])) { for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $_block = substr($_text, $_i, '.$block_size.'); if (strlen($_block) > strlen($_buffer["xor"])) { $in = $_xor; '.$encrypt_block.' $_xor = $in; $_buffer["xor"].= $_xor; } $_key = \phpseclib\Common\Functions\Strings::shift($_buffer["xor"], '.$block_size.'); $_plaintext.= $_block ^ $_key; } } else { for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $in = $_xor; '.$encrypt_block.' $_xor = $in; $_plaintext.= substr($_text, $_i, '.$block_size.') ^ $_xor; } $_key = $_xor; } if ($this->continuousBuffer) { $this->decryptIV = $_xor; if ($_start = $_ciphertext_len % '.$block_size.') { $_buffer["xor"] = substr($_key, $_start) . $_buffer["xor"]; } } return $_plaintext; '; break; case self::MODE_STREAM: $encrypt = $init_encrypt . ' $_ciphertext = ""; '.$encrypt_block.' return $_ciphertext; '; $decrypt = $init_decrypt . ' $_plaintext = ""; '.$decrypt_block.' return $_plaintext; '; break; // case self::MODE_CBC: default: $encrypt = $init_encrypt . ' $_ciphertext = ""; $_plaintext_len = strlen($_text); $in = $this->encryptIV; for ($_i = 0; $_i < $_plaintext_len; $_i+= '.$block_size.') { $in = substr($_text, $_i, '.$block_size.') ^ $in; '.$encrypt_block.' $_ciphertext.= $in; } if ($this->continuousBuffer) { $this->encryptIV = $in; } return $_ciphertext; '; $decrypt = $init_decrypt . ' $_plaintext = ""; $_text = str_pad($_text, strlen($_text) + ('.$block_size.' - strlen($_text) % '.$block_size.') % '.$block_size.', chr(0)); $_ciphertext_len = strlen($_text); $_iv = $this->decryptIV; for ($_i = 0; $_i < $_ciphertext_len; $_i+= '.$block_size.') { $in = $_block = substr($_text, $_i, '.$block_size.'); '.$decrypt_block.' $_plaintext.= $in ^ $_iv; $_iv = $_block; } if ($this->continuousBuffer) { $this->decryptIV = $_iv; } return $this->unpad($_plaintext); '; break; } eval('$func = function ($_action, $_text) { ' . $init_crypt . 'if ($_action == "encrypt") { ' . $encrypt . ' } else { ' . $decrypt . ' }};'); return \Closure::bind($func, $this, static::class); } /** * Convert float to int * * On ARM CPUs converting floats to ints doesn't always work * * @access private * @param string $x * @return int */ protected static function safe_intval($x) { switch (true) { case is_int($x): // PHP 5.3, per http://php.net/releases/5_3_0.php, introduced "more consistent float rounding" case (php_uname('m') & "\xDF\xDF\xDF") != 'ARM': return $x; } return (fmod($x, 0x80000000) & 0x7FFFFFFF) | ((fmod(floor($x / 0x80000000), 2) & 1) << 31); } /** * eval()'able string for in-line float to int * * @access private * @return string */ protected static function safe_intval_inline() { switch (true) { case defined('PHP_INT_SIZE') && PHP_INT_SIZE == 8: case (php_uname('m') & "\xDF\xDF\xDF") != 'ARM': return '%s'; break; default: $safeint = '(is_int($temp = %s) ? $temp : (fmod($temp, 0x80000000) & 0x7FFFFFFF) | '; return $safeint . '((fmod(floor($temp / 0x80000000), 2) & 1) << 31))'; } } }