0,0 → 1,3419 |
<?php |
|
/** |
* Base Class for all \phpseclib3\Crypt\* cipher classes |
* |
* PHP version 5 |
* |
* Internally for phpseclib developers: |
* If you plan to add a new cipher class, please note following rules: |
* |
* - The new \phpseclib3\Crypt\* cipher class should extend \phpseclib3\Crypt\Common\SymmetricKey |
* |
* - Following methods are then required to be overridden/overloaded: |
* |
* - encryptBlock() |
* |
* - decryptBlock() |
* |
* - setupKey() |
* |
* - All other methods are optional to be overridden/overloaded |
* |
* - Look at the source code of the current ciphers how they extend \phpseclib3\Crypt\Common\SymmetricKey |
* and take one of them as a start up for the new cipher class. |
* |
* - Please read all the other comments/notes/hints here also for each class var/method |
* |
* @category Crypt |
* @package Base |
* @author Jim Wigginton <terrafrost@php.net> |
* @author Hans-Juergen Petrich <petrich@tronic-media.com> |
* @copyright 2007 Jim Wigginton |
* @license http://www.opensource.org/licenses/mit-license.html MIT License |
* @link http://phpseclib.sourceforge.net |
*/ |
|
namespace phpseclib3\Crypt\Common; |
|
use phpseclib3\Common\Functions\Strings; |
use phpseclib3\Crypt\Hash; |
use phpseclib3\Exception\BadDecryptionException; |
use phpseclib3\Exception\BadModeException; |
use phpseclib3\Exception\InconsistentSetupException; |
use phpseclib3\Exception\InsufficientSetupException; |
use phpseclib3\Exception\UnsupportedAlgorithmException; |
use phpseclib3\Math\BigInteger; |
use phpseclib3\Math\BinaryField; |
use phpseclib3\Math\PrimeField; |
|
/** |
* Base Class for all \phpseclib3\Crypt\* cipher classes |
* |
* @package Base |
* @author Jim Wigginton <terrafrost@php.net> |
* @author Hans-Juergen Petrich <petrich@tronic-media.com> |
*/ |
abstract class SymmetricKey |
{ |
/** |
* 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 |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
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 |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
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 |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
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 |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_CFB = 3; |
/** |
* Encrypt / decrypt using the Cipher Feedback mode (8bit) |
* |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_CFB8 = 7; |
/** |
* Encrypt / decrypt using the Output Feedback mode (8bit) |
* |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_OFB8 = 8; |
/** |
* Encrypt / decrypt using the Output Feedback mode. |
* |
* @link http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation#Output_feedback_.28OFB.29 |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_OFB = 4; |
/** |
* Encrypt / decrypt using Galois/Counter mode. |
* |
* @link https://en.wikipedia.org/wiki/Galois/Counter_Mode |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_GCM = 5; |
/** |
* Encrypt / decrypt using streaming mode. |
* |
* @access public |
* @see \phpseclib3\Crypt\Common\SymmetricKey::encrypt() |
* @see \phpseclib3\Crypt\Common\SymmetricKey::decrypt() |
*/ |
const MODE_STREAM = 6; |
|
/** |
* Mode Map |
* |
* @access private |
* @see \phpseclib3\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, |
'ofb8' => self::MODE_OFB8, |
'gcm' => self::MODE_GCM, |
'stream' => self::MODE_STREAM |
]; |
|
/** |
* Base value for the internal implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_INTERNAL = 1; |
/** |
* Base value for the eval() implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_EVAL = 2; |
/** |
* Base value for the mcrypt implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_MCRYPT = 3; |
/** |
* Base value for the openssl implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_OPENSSL = 4; |
/** |
* Base value for the libsodium implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_LIBSODIUM = 5; |
/** |
* Base value for the openssl / gcm implementation $engine switch |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::__construct() |
*/ |
const ENGINE_OPENSSL_GCM = 6; |
|
/** |
* Engine Reverse Map |
* |
* @access private |
* @see \phpseclib3\Crypt\Common\SymmetricKey::getEngine() |
*/ |
const ENGINE_MAP = [ |
self::ENGINE_INTERNAL => 'PHP', |
self::ENGINE_EVAL => 'Eval', |
self::ENGINE_MCRYPT => 'mcrypt', |
self::ENGINE_OPENSSL => 'OpenSSL', |
self::ENGINE_LIBSODIUM => 'libsodium', |
self::ENGINE_OPENSSL_GCM => 'OpenSSL (GCM)' |
]; |
|
/** |
* 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 |
*/ |
protected $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 |
*/ |
protected $enbuffer; |
|
/** |
* Decryption buffer for CTR, OFB and CFB modes |
* |
* @see self::decrypt() |
* @see self::clearBuffers() |
* @var array |
* @access private |
*/ |
protected $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 \phpseclib3\Crypt\Twofish::setKey() |
* @see \phpseclib3\Crypt\Twofish::setIV() |
* @var bool |
* @access private |
*/ |
private $enchanged = true; |
|
/** |
* Does the demcrypt resource need to be (re)initialized? |
* |
* @see \phpseclib3\Crypt\Twofish::setKey() |
* @see \phpseclib3\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; |
|
/** |
* Does Eval engie need to be (re)initialized? |
* |
* @see self::setup() |
* @var bool |
* @access private |
*/ |
protected $nonIVChanged = 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_LIBSODIUM (very fast, php-extension: libsodium, extension_loaded('libsodium') required) |
* - self::ENGINE_OPENSSL_GCM (very fast, php-extension: openssl, extension_loaded('openssl') required) |
* - 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() |
* @var Callback |
* @access private |
*/ |
protected $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; |
|
/** |
* Hash subkey for GHASH |
* |
* @see self::setupGCM() |
* @see self::ghash() |
* @var BinaryField\Integer |
* @access private |
*/ |
private $h; |
|
/** |
* Additional authenticated data |
* |
* @var string |
* @access private |
*/ |
protected $aad = ''; |
|
/** |
* Authentication Tag produced after a round of encryption |
* |
* @var string |
* @access private |
*/ |
protected $newtag = false; |
|
/** |
* Authentication Tag to be verified during decryption |
* |
* @var string |
* @access private |
*/ |
protected $oldtag = false; |
|
/** |
* GCM Binary Field |
* |
* @see self::__construct() |
* @see self::ghash() |
* @var BinaryField |
* @access private |
*/ |
private static $gcmField; |
|
/** |
* Poly1305 Prime Field |
* |
* @see self::enablePoly1305() |
* @see self::poly1305() |
* @var PrimeField |
* @access private |
*/ |
private static $poly1305Field; |
|
/** |
* Poly1305 Key |
* |
* @see self::setPoly1305Key() |
* @see self::poly1305() |
* @var string |
* @access private |
*/ |
protected $poly1305Key; |
|
/** |
* Poly1305 Flag |
* |
* @see self::setPoly1305Key() |
* @see self::enablePoly1305() |
* @var boolean |
* @access private |
*/ |
protected $usePoly1305 = false; |
|
/** |
* The Original Initialization Vector |
* |
* GCM uses the nonce to build the IV but we want to be able to distinguish between nonce-derived |
* IV's and user-set IV's |
* |
* @see self::setIV() |
* @var string |
* @access private |
*/ |
private $origIV = false; |
|
/** |
* Nonce |
* |
* Only used with GCM. We could re-use setIV() but nonce's can be of a different length and |
* toggling between GCM and other modes could be more complicated if we re-used setIV() |
* |
* @see self::setNonce() |
* @var string |
* @access private |
*/ |
protected $nonce = false; |
|
/** |
* Default Constructor. |
* |
* $mode could be: |
* |
* - ecb |
* |
* - cbc |
* |
* - ctr |
* |
* - cfb |
* |
* - cfb8 |
* |
* - ofb |
* |
* - ofb8 |
* |
* - gcm |
* |
* @param string $mode |
* @access public |
* @throws BadModeException if an invalid / unsupported mode is provided |
*/ |
public function __construct($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 BadModeException('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_OFB8: |
case self::MODE_STREAM: |
$this->paddable = false; |
break; |
case self::MODE_GCM: |
if ($this->block_size != 16) { |
throw new BadModeException('GCM is only valid for block ciphers with a block size of 128 bits'); |
} |
if (!isset(self::$gcmField)) { |
self::$gcmField = new BinaryField(128, 7, 2, 1, 0); |
} |
$this->paddable = false; |
break; |
default: |
throw new BadModeException('No valid mode has been specified'); |
} |
|
$this->mode = $mode; |
} |
|
/** |
* Sets the initialization vector. |
* |
* setIV() is not required when ecb or gcm modes are being used. |
* |
* {@internal Can be overwritten by a sub class, but does not have to be} |
* |
* @access public |
* @param string $iv |
* @throws \LengthException if the IV length isn't equal to the block size |
* @throws \BadMethodCallException if an IV is provided when one shouldn't be |
*/ |
public function setIV($iv) |
{ |
if ($this->mode == self::MODE_ECB) { |
throw new \BadMethodCallException('This mode does not require an IV.'); |
} |
|
if ($this->mode == self::MODE_GCM) { |
throw new \BadMethodCallException('Use setNonce instead'); |
} |
|
if (!$this->usesIV()) { |
throw new \BadMethodCallException('This algorithm does not use an IV.'); |
} |
|
if (strlen($iv) != $this->block_size) { |
throw new \LengthException('Received initialization vector of size ' . strlen($iv) . ', but size ' . $this->block_size . ' is required'); |
} |
|
$this->iv = $this->origIV = $iv; |
$this->changed = true; |
} |
|
/** |
* Enables Poly1305 mode. |
* |
* Once enabled Poly1305 cannot be disabled. |
* |
* @access public |
* @throws \BadMethodCallException if Poly1305 is enabled whilst in GCM mode |
*/ |
public function enablePoly1305() |
{ |
if ($this->mode == self::MODE_GCM) { |
throw new \BadMethodCallException('Poly1305 cannot be used in GCM mode'); |
} |
|
$this->usePoly1305 = true; |
} |
|
/** |
* Enables Poly1305 mode. |
* |
* Once enabled Poly1305 cannot be disabled. If $key is not passed then an attempt to call createPoly1305Key |
* will be made. |
* |
* @access public |
* @param string $key optional |
* @throws \LengthException if the key isn't long enough |
* @throws \BadMethodCallException if Poly1305 is enabled whilst in GCM mode |
*/ |
public function setPoly1305Key($key = null) |
{ |
if ($this->mode == self::MODE_GCM) { |
throw new \BadMethodCallException('Poly1305 cannot be used in GCM mode'); |
} |
|
if (!is_string($key) || strlen($key) != 32) { |
throw new \LengthException('The Poly1305 key must be 32 bytes long (256 bits)'); |
} |
|
if (!isset(self::$poly1305Field)) { |
// 2^130-5 |
self::$poly1305Field = new PrimeField(new BigInteger('3fffffffffffffffffffffffffffffffb', 16)); |
} |
|
$this->poly1305Key = $key; |
$this->usePoly1305 = true; |
} |
|
/** |
* Sets the nonce. |
* |
* setNonce() is only required when gcm is used |
* |
* @access public |
* @param string $nonce |
* @throws \BadMethodCallException if an nonce is provided when one shouldn't be |
*/ |
public function setNonce($nonce) |
{ |
if ($this->mode != self::MODE_GCM) { |
throw new \BadMethodCallException('Nonces are only used in GCM mode.'); |
} |
|
$this->nonce = $nonce; |
$this->setEngine(); |
} |
|
/** |
* Sets additional authenticated data |
* |
* setAAD() is only used by gcm or in poly1305 mode |
* |
* @access public |
* @param string $aad |
* @throws \BadMethodCallException if mode isn't GCM or if poly1305 isn't being utilized |
*/ |
public function setAAD($aad) |
{ |
if ($this->mode != self::MODE_GCM && !$this->usePoly1305) { |
throw new \BadMethodCallException('Additional authenticated data is only utilized in GCM mode or with Poly1305'); |
} |
|
$this->aad = $aad; |
} |
|
/** |
* Returns whether or not the algorithm uses an IV |
* |
* @access public |
* @return bool |
*/ |
public function usesIV() |
{ |
return $this->mode != self::MODE_GCM && $this->mode != self::MODE_ECB; |
} |
|
/** |
* Returns whether or not the algorithm uses a nonce |
* |
* @access public |
* @return bool |
*/ |
public function usesNonce() |
{ |
return $this->mode == self::MODE_GCM; |
} |
|
/** |
* 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 InconsistentSetupException('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. |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @access public |
* @param string $key |
*/ |
public function setKey($key) |
{ |
if ($this->explicit_key_length !== false && strlen($key) != $this->explicit_key_length) { |
throw new InconsistentSetupException('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->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 |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see Crypt/Hash.php |
* @param string $password |
* @param string $method |
* @param string[] ...$func_args |
* @throws \LengthException if pbkdf1 is being used and the derived key length exceeds the hash length |
* @return bool |
* @access public |
*/ |
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])) { |
if ($func_args[3] <= 0) { |
throw new \LengthException('Derived key length cannot be longer 0 or less'); |
} |
$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, $dkLen >> 1)); |
} |
|
return true; |
case !in_array($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, $dkLen, true); |
} |
break; |
default: |
throw new UnsupportedAlgorithmException($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 \phpseclib3\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. |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see self::decrypt() |
* @access public |
* @param string $plaintext |
* @return string $ciphertext |
*/ |
public function encrypt($plaintext) |
{ |
if ($this->paddable) { |
$plaintext = $this->pad($plaintext); |
} |
|
$this->setup(); |
|
if ($this->mode == self::MODE_GCM) { |
$oldIV = $this->iv; |
Strings::increment_str($this->iv); |
$cipher = new static('ctr'); |
$cipher->setKey($this->key); |
$cipher->setIV($this->iv); |
$ciphertext = $cipher->encrypt($plaintext); |
|
$s = $this->ghash( |
self::nullPad128($this->aad) . |
self::nullPad128($ciphertext) . |
self::len64($this->aad) . |
self::len64($ciphertext) |
); |
$cipher->encryptIV = $this->iv = $this->encryptIV = $this->decryptIV = $oldIV; |
$this->newtag = $cipher->encrypt($s); |
return $ciphertext; |
} |
|
if (isset($this->poly1305Key)) { |
$cipher = clone $this; |
unset($cipher->poly1305Key); |
$this->usePoly1305 = false; |
$ciphertext = $cipher->encrypt($plaintext); |
$this->newtag = $this->poly1305($ciphertext); |
return $ciphertext; |
} |
|
if ($this->engine === self::ENGINE_OPENSSL) { |
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_OFB8: |
$ciphertext = ''; |
$len = strlen($plaintext); |
$iv = $this->encryptIV; |
|
for ($i = 0; $i < $len; ++$i) { |
$xor = openssl_encrypt($iv, $this->cipher_name_openssl_ecb, $this->key, $this->openssl_options, $this->decryptIV); |
$ciphertext .= $plaintext[$i] ^ $xor; |
$iv = substr($iv, 1) . $xor[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->encryptIV = $iv; |
} |
break; |
case self::MODE_OFB: |
return $this->openssl_ofb_process($plaintext, $this->encryptIV, $this->enbuffer); |
} |
} |
|
if ($this->engine === self::ENGINE_MCRYPT) { |
set_error_handler(function () { |
}); |
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; |
} |
|
restore_error_handler(); |
|
return $ciphertext; |
} |
|
$ciphertext = mcrypt_generic($this->enmcrypt, $plaintext); |
|
if (!$this->continuousBuffer) { |
mcrypt_generic_init($this->enmcrypt, $this->key, $this->getIV($this->encryptIV)); |
} |
|
restore_error_handler(); |
|
return $ciphertext; |
} |
|
if ($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); |
Strings::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); |
Strings::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_OFB8: |
$ciphertext = ''; |
$len = strlen($plaintext); |
$iv = $this->encryptIV; |
|
for ($i = 0; $i < $len; ++$i) { |
$xor = $this->encryptBlock($iv); |
$ciphertext .= $plaintext[$i] ^ $xor; |
$iv = substr($iv, 1) . $xor[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->encryptIV = $iv; |
} |
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. |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see self::encrypt() |
* @access public |
* @param string $ciphertext |
* @return string $plaintext |
* @throws \LengthException if we're inside a block cipher and the ciphertext length is not a multiple of the block size |
*/ |
public function decrypt($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 . ')'); |
} |
$this->setup(); |
|
if ($this->mode == self::MODE_GCM || isset($this->poly1305Key)) { |
if ($this->oldtag === false) { |
throw new InsufficientSetupException('Authentication Tag has not been set'); |
} |
|
if (isset($this->poly1305Key)) { |
$newtag = $this->poly1305($ciphertext); |
} else { |
$oldIV = $this->iv; |
Strings::increment_str($this->iv); |
$cipher = new static('ctr'); |
$cipher->setKey($this->key); |
$cipher->setIV($this->iv); |
$plaintext = $cipher->decrypt($ciphertext); |
|
$s = $this->ghash( |
self::nullPad128($this->aad) . |
self::nullPad128($ciphertext) . |
self::len64($this->aad) . |
self::len64($ciphertext) |
); |
$cipher->encryptIV = $this->iv = $this->encryptIV = $this->decryptIV = $oldIV; |
$newtag = $cipher->encrypt($s); |
} |
if ($this->oldtag != substr($newtag, 0, strlen($newtag))) { |
$cipher = clone $this; |
unset($cipher->poly1305Key); |
$this->usePoly1305 = false; |
$plaintext = $cipher->decrypt($ciphertext); |
$this->oldtag = false; |
throw new BadDecryptionException('Derived authentication tag and supplied authentication tag do not match'); |
} |
$this->oldtag = false; |
return $plaintext; |
} |
|
if ($this->engine === self::ENGINE_OPENSSL) { |
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_OFB8: |
$plaintext = ''; |
$len = strlen($ciphertext); |
$iv = $this->decryptIV; |
|
for ($i = 0; $i < $len; ++$i) { |
$xor = openssl_encrypt($iv, $this->cipher_name_openssl_ecb, $this->key, $this->openssl_options, $this->decryptIV); |
$plaintext .= $ciphertext[$i] ^ $xor; |
$iv = substr($iv, 1) . $xor[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->decryptIV = $iv; |
} |
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) { |
set_error_handler(function () { |
}); |
$block_size = $this->block_size; |
if ($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; |
} |
|
restore_error_handler(); |
|
return $plaintext; |
} |
|
$plaintext = mdecrypt_generic($this->demcrypt, $ciphertext); |
|
if (!$this->continuousBuffer) { |
mcrypt_generic_init($this->demcrypt, $this->key, $this->getIV($this->decryptIV)); |
} |
|
restore_error_handler(); |
|
return $this->paddable ? $this->unpad($plaintext) : $plaintext; |
} |
|
if ($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); |
Strings::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); |
Strings::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_OFB8: |
$plaintext = ''; |
$len = strlen($ciphertext); |
$iv = $this->decryptIV; |
|
for ($i = 0; $i < $len; ++$i) { |
$xor = $this->encryptBlock($iv); |
$plaintext .= $ciphertext[$i] ^ $xor; |
$iv = substr($iv, 1) . $xor[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->decryptIV = $iv; |
} |
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 authentication tag |
* |
* Only used in GCM or Poly1305 mode |
* |
* @see self::encrypt() |
* @param int $length optional |
* @return string |
* @access public |
* @throws \LengthException if $length isn't of a sufficient length |
* @throws \RuntimeException if GCM mode isn't being used |
*/ |
public function getTag($length = 16) |
{ |
if ($this->mode != self::MODE_GCM && !$this->usePoly1305) { |
throw new \BadMethodCallException('Authentication tags are only utilized in GCM mode or with Poly1305'); |
} |
|
if ($this->newtag === false) { |
throw new \BadMethodCallException('A tag can only be returned after a round of encryption has been performed'); |
} |
|
// the tag is 128-bits. it can't be greater than 16 bytes because that's bigger than the tag is. if it |
// were 0 you might as well be doing CTR and less than 4 provides minimal security that could be trivially |
// easily brute forced. |
// see https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=36 |
// for more info |
if ($length < 4 || $length > 16) { |
throw new \LengthException('The authentication tag must be between 4 and 16 bytes long'); |
} |
|
return $length == 16 ? |
$this->newtag : |
substr($this->newtag, 0, $length); |
} |
|
/** |
* Sets the authentication tag |
* |
* Only used in GCM mode |
* |
* @see self::decrypt() |
* @param string $tag |
* @access public |
* @throws \LengthException if $length isn't of a sufficient length |
* @throws \RuntimeException if GCM mode isn't being used |
*/ |
public function setTag($tag) |
{ |
if ($this->usePoly1305 && !isset($this->poly1305Key) && method_exists($this, 'createPoly1305Key')) { |
$this->createPoly1305Key(); |
} |
|
if ($this->mode != self::MODE_GCM && !$this->usePoly1305) { |
throw new \BadMethodCallException('Authentication tags are only utilized in GCM mode or with Poly1305'); |
} |
|
$length = strlen($tag); |
if ($length < 4 || $length > 16) { |
throw new \LengthException('The authentication tag must be between 4 and 16 bytes long'); |
} |
$this->oldtag = $tag; |
} |
|
/** |
* Get the IV |
* |
* mcrypt requires an IV even if ECB is used |
* |
* @see self::encrypt() |
* @see self::decrypt() |
* @param string $iv |
* @return string |
* @access private |
*/ |
protected function getIV($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, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); |
} |
Strings::increment_str($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, $key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING); |
Strings::increment_str($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) { |
Strings::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: |
case self::MODE_GCM: |
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: |
* |
* <code> |
* echo $rijndael->encrypt(substr($plaintext, 0, 16)); |
* echo $rijndael->encrypt(substr($plaintext, 16, 16)); |
* </code> |
* <code> |
* echo $rijndael->encrypt($plaintext); |
* </code> |
* |
* The solution is to enable the continuous buffer. Although this will resolve the above discrepancy, it creates |
* another, as demonstrated with the following: |
* |
* <code> |
* $rijndael->encrypt(substr($plaintext, 0, 16)); |
* echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16))); |
* </code> |
* <code> |
* echo $rijndael->decrypt($rijndael->encrypt(substr($plaintext, 16, 16))); |
* </code> |
* |
* With the continuous buffer disabled, these would yield the same output. With it enabled, they yield different |
* outputs. The reason is due to the fact that the initialization vector's change after every encryption / |
* decryption round when the continuous buffer is enabled. When it's disabled, they remain constant. |
* |
* Put another way, when the continuous buffer is enabled, the state of the \phpseclib3\Crypt\*() object changes after each |
* encryption / decryption round, whereas otherwise, it'd remain constant. For this reason, it's recommended that |
* continuous buffers not be used. They do offer better security and are, in fact, sometimes required (SSH uses them), |
* however, they are also less intuitive and more likely to cause you problems. |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see self::disableContinuousBuffer() |
* @access public |
*/ |
public function enableContinuousBuffer() |
{ |
if ($this->mode == self::MODE_ECB) { |
return; |
} |
|
if ($this->mode == self::MODE_GCM) { |
throw new \BadMethodCallException('This mode does not run in continuous mode'); |
} |
|
$this->continuousBuffer = true; |
|
$this->setEngine(); |
} |
|
/** |
* Treat consecutive packets as if they are a discontinuous buffer. |
* |
* The default behavior. |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see self::enableContinuousBuffer() |
* @access public |
*/ |
public function disableContinuousBuffer() |
{ |
if ($this->mode == self::MODE_ECB) { |
return; |
} |
if (!$this->continuousBuffer) { |
return; |
} |
|
$this->continuousBuffer = false; |
|
$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: |
$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: |
set_error_handler(function () { |
}); |
$result = $this->cipher_name_mcrypt && |
extension_loaded('mcrypt') && |
in_array($this->cipher_name_mcrypt, mcrypt_list_algorithms()); |
restore_error_handler(); |
return $result; |
case self::ENGINE_EVAL: |
return method_exists($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: |
* |
* - libsodium[very fast] |
* |
* - 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_LIBSODIUM; |
|
$this->setEngine(); |
} |
|
/** |
* Returns the engine currently being utilized |
* |
* @see self::setEngine() |
* @access public |
*/ |
public function getEngine() |
{ |
return self::ENGINE_MAP[$this->engine]; |
} |
|
/** |
* Sets the engine as appropriate |
* |
* @see self::__construct() |
* @access private |
*/ |
protected function setEngine() |
{ |
$this->engine = null; |
|
$candidateEngines = [ |
self::ENGINE_LIBSODIUM, |
self::ENGINE_OPENSSL_GCM, |
self::ENGINE_OPENSSL, |
self::ENGINE_MCRYPT, |
self::ENGINE_EVAL |
]; |
if (isset($this->preferredEngine)) { |
$temp = [$this->preferredEngine]; |
$candidateEngines = array_merge( |
$temp, |
array_diff($candidateEngines, $temp) |
); |
} |
foreach ($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) { |
set_error_handler(function () { |
}); |
// 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; |
} |
restore_error_handler(); |
} |
|
$this->changed = $this->nonIVChanged = true; |
} |
|
/** |
* Encrypts a block |
* |
* Note: Must be extended by the child \phpseclib3\Crypt\* class |
* |
* @access private |
* @param string $in |
* @return string |
*/ |
abstract protected function encryptBlock($in); |
|
/** |
* Decrypts a block |
* |
* Note: Must be extended by the child \phpseclib3\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 \phpseclib3\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 $changed === true |
* typically this happens when using one or more of following public methods: |
* |
* - setKey() |
* |
* - setIV() |
* |
* - disableContinuousBuffer() |
* |
* - First run of encrypt() / decrypt() with no init-settings |
* |
* {@internal setup() is always called before en/decryption.} |
* |
* {@internal Could, but not must, extend by the child Crypt_* class} |
* |
* @see self::setKey() |
* @see self::setIV() |
* @see self::disableContinuousBuffer() |
* @access private |
*/ |
protected function setup() |
{ |
if (!$this->changed) { |
return; |
} |
|
$this->changed = false; |
|
if ($this->usePoly1305 && !isset($this->poly1305Key) && method_exists($this, 'createPoly1305Key')) { |
$this->createPoly1305Key(); |
} |
|
$this->enbuffer = $this->debuffer = ['ciphertext' => '', 'xor' => '', 'pos' => 0, 'enmcrypt_init' => true]; |
//$this->newtag = $this->oldtag = false; |
|
if ($this->usesNonce()) { |
if ($this->nonce === false) { |
throw new InsufficientSetupException('No nonce has been defined'); |
} |
if ($this->mode == self::MODE_GCM && !in_array($this->engine, [self::ENGINE_LIBSODIUM, self::ENGINE_OPENSSL_GCM])) { |
$this->setupGCM(); |
} |
} else { |
$this->iv = $this->origIV; |
} |
|
if ($this->iv === false && !in_array($this->mode, [self::MODE_STREAM, self::MODE_ECB])) { |
if ($this->mode != self::MODE_GCM || !in_array($this->engine, [self::ENGINE_LIBSODIUM, self::ENGINE_OPENSSL_GCM])) { |
throw new InsufficientSetupException('No IV has been defined'); |
} |
} |
|
if ($this->key === false) { |
throw new InsufficientSetupException('No key has been defined'); |
} |
|
$this->encryptIV = $this->decryptIV = $this->iv; |
|
switch ($this->engine) { |
case self::ENGINE_MCRYPT: |
$this->enchanged = $this->dechanged = true; |
|
set_error_handler(function () { |
}); |
|
if (!isset($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_OFB8 => MCRYPT_MODE_OFB, |
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)); |
} |
|
restore_error_handler(); |
|
break; |
case self::ENGINE_INTERNAL: |
$this->setupKey(); |
break; |
case self::ENGINE_EVAL: |
if ($this->nonIVChanged) { |
$this->setupKey(); |
$this->setupInlineCrypt(); |
} |
} |
|
$this->nonIVChanged = false; |
} |
|
/** |
* 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 > $this->block_size) { |
throw new BadDecryptionException("The ciphertext has an invalid padding length ($length) compared to the block size ({$this->block_size})"); |
} |
|
return substr($text, 0, -$length); |
} |
|
/** |
* 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 \phpseclib3\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 |
* |
* {@internal If a Crypt_* class providing inline crypting it must extend _setupInlineCrypt()} |
* |
* @see self::setup() |
* @see self::createInlineCryptFunction() |
* @see self::encrypt() |
* @see self::decrypt() |
* @access private |
*/ |
//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: |
* |
* <code> |
* +----------------------------------------------------------------------------------------------+ |
* | 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; | |
* | } | |
* | } | |
* +----------------------------------------------------------------------------------------------+ |
* </code> |
* |
* See also the \phpseclib3\Crypt\*::_setupInlineCrypt()'s for |
* productive inline $cipher_code's how they works. |
* |
* Structure of: |
* <code> |
* $cipher_code = [ |
* 'init_crypt' => (string) '', // optional |
* 'init_encrypt' => (string) '', // optional |
* 'init_decrypt' => (string) '', // optional |
* 'encrypt_block' => (string) '', // required |
* 'decrypt_block' => (string) '' // required |
* ]; |
* </code> |
* |
* @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; |
' . $encrypt_block . ' |
\phpseclib3\Common\Functions\Strings::increment_str($_xor); |
$_buffer["ciphertext"].= $in; |
} |
$_key = \phpseclib3\Common\Functions\Strings::shift($_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; |
' . $encrypt_block . ' |
\phpseclib3\Common\Functions\Strings::increment_str($_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; |
' . $encrypt_block . ' |
\phpseclib3\Common\Functions\Strings::increment_str($_xor); |
$_buffer["ciphertext"].= $in; |
} |
$_key = \phpseclib3\Common\Functions\Strings::shift($_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; |
' . $encrypt_block . ' |
\phpseclib3\Common\Functions\Strings::increment_str($_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_OFB8: |
$encrypt = $init_encrypt . ' |
$_ciphertext = ""; |
$_len = strlen($_text); |
$_iv = $this->encryptIV; |
|
for ($_i = 0; $_i < $_len; ++$_i) { |
$in = $_iv; |
' . $encrypt_block . ' |
$_ciphertext.= $_text[$_i] ^ $in; |
$_iv = substr($_iv, 1) . $in[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->encryptIV = $_iv; |
} |
|
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) . $in[0]; |
} |
|
if ($this->continuousBuffer) { |
$this->decryptIV = $_iv; |
} |
|
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; |
} |
$_key = \phpseclib3\Common\Functions\Strings::shift($_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; |
} |
$_key = \phpseclib3\Common\Functions\Strings::shift($_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; |
} |
|
// Before discrediting this, please read the following: |
// @see https://github.com/phpseclib/phpseclib/issues/1293 |
// @see https://github.com/phpseclib/phpseclib/pull/1143 |
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))'; |
} |
} |
|
/** |
* Sets up GCM parameters |
* |
* See steps 1-2 of https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=23 |
* for more info |
* |
* @access private |
*/ |
private function setupGCM() |
{ |
// don't keep on re-calculating $this->h |
if (!$this->h || $this->h->key != $this->key) { |
$cipher = new static('ecb'); |
$cipher->setKey($this->key); |
$cipher->disablePadding(); |
|
$this->h = self::$gcmField->newInteger( |
Strings::switchEndianness($cipher->encrypt("\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0")) |
); |
$this->h->key = $this->key; |
} |
|
if (strlen($this->nonce) == 12) { |
$this->iv = $this->nonce . "\0\0\0\1"; |
} else { |
$this->iv = $this->ghash( |
self::nullPad128($this->nonce) . str_repeat("\0", 8) . self::len64($this->nonce) |
); |
} |
} |
|
/** |
* Performs GHASH operation |
* |
* See https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=20 |
* for more info |
* |
* @see self::decrypt() |
* @see self::encrypt() |
* @access private |
* @param string $x |
* @return string |
*/ |
private function ghash($x) |
{ |
$h = $this->h; |
$y = ["\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"]; |
$x = str_split($x, 16); |
$n = 0; |
// the switchEndianness calls are necessary because the multiplication algorithm in BinaryField/Integer |
// interprets strings as polynomials in big endian order whereas in GCM they're interpreted in little |
// endian order per https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38d.pdf#page=19. |
// big endian order is what binary field elliptic curves use per http://www.secg.org/sec1-v2.pdf#page=18. |
|
// we could switchEndianness here instead of in the while loop but doing so in the while loop seems like it |
// might be slightly more performant |
//$x = Strings::switchEndianness($x); |
foreach ($x as $xn) { |
$xn = Strings::switchEndianness($xn); |
$t = $y[$n] ^ $xn; |
$temp = self::$gcmField->newInteger($t); |
$y[++$n] = $temp->multiply($h)->toBytes(); |
$y[$n] = substr($y[$n], 1); |
} |
$y[$n] = Strings::switchEndianness($y[$n]); |
return $y[$n]; |
} |
|
/** |
* Returns the bit length of a string in a packed format |
* |
* @see self::decrypt() |
* @see self::encrypt() |
* @see self::setupGCM() |
* @access private |
* @param string $str |
* @return string |
*/ |
private static function len64($str) |
{ |
return "\0\0\0\0" . pack('N', 8 * strlen($str)); |
} |
|
/** |
* NULL pads a string to be a multiple of 128 |
* |
* @see self::decrypt() |
* @see self::encrypt() |
* @see self::setupGCM() |
* @access private |
* @param string $str |
* @return string |
*/ |
protected static function nullPad128($str) |
{ |
$len = strlen($str); |
return $str . str_repeat("\0", 16 * ceil($len / 16) - $len); |
} |
|
/** |
* Calculates Poly1305 MAC |
* |
* On my system ChaCha20, with libsodium, takes 0.5s. With this custom Poly1305 implementation |
* it takes 1.2s. |
* |
* @see self::decrypt() |
* @see self::encrypt() |
* @access private |
* @param string $text |
* @return string |
*/ |
protected function poly1305($text) |
{ |
$s = $this->poly1305Key; // strlen($this->poly1305Key) == 32 |
$r = Strings::shift($s, 16); |
$r = strrev($r); |
$r &= "\x0f\xff\xff\xfc\x0f\xff\xff\xfc\x0f\xff\xff\xfc\x0f\xff\xff\xff"; |
$s = strrev($s); |
|
$r = self::$poly1305Field->newInteger(new BigInteger($r, 256)); |
$s = self::$poly1305Field->newInteger(new BigInteger($s, 256)); |
$a = self::$poly1305Field->newInteger(new BigInteger()); |
|
$blocks = str_split($text, 16); |
foreach ($blocks as $block) { |
$n = strrev($block . chr(1)); |
$n = self::$poly1305Field->newInteger(new BigInteger($n, 256)); |
$a = $a->add($n); |
$a = $a->multiply($r); |
} |
$r = $a->toBigInteger()->add($s->toBigInteger()); |
$mask = "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"; |
return strrev($r->toBytes()) & $mask; |
} |
|
/** |
* Return the mode |
* |
* You can do $obj instanceof AES or whatever to get the cipher but you can't do that to get the mode |
* |
* @access public |
* @return string |
*/ |
public function getMode() |
{ |
return array_flip(self::MODE_MAP)[$this->mode]; |
} |
} |