phpseclib\Crypt\RC2 Class Reference

Inheritance diagram for phpseclib\Crypt\RC2:

Collaboration diagram for phpseclib\Crypt\RC2:

Public Member Functions
	isValidEngine ($engine)
	Test for engine validity. More...
	setKeyLength ($length)
	Sets the key length. More...
	getKeyLength ()
	Returns the current key length. More...
	setKey ($key, $t1=0)
	Sets the key. More...
	encrypt ($plaintext)
	Encrypts a message. More...
	decrypt ($ciphertext)
	Decrypts a message. More...
	_encryptBlock ($in)
	Encrypts a block. More...
	_decryptBlock ($in)
	Decrypts a block. More...
	_setupMcrypt ()
	Setup the \phpseclib\Crypt\Base::ENGINE_MCRYPT $engine. More...
	_setupKey ()
	Creates the key schedule. More...
	_setupInlineCrypt ()
	Setup the performance-optimized function for de/encrypt() More...
Public Member Functions inherited from phpseclib\Crypt\Base
	__construct ($mode=self::MODE_CBC)
	Default Constructor. More...
	setIV ($iv)
	Sets the initialization vector. More...
	setKeyLength ($length)
	Sets the key length. More...
	getKeyLength ()
	Returns the current key length in bits. More...
	getBlockLength ()
	Returns the current block length in bits. More...
	setKey ($key)
	Sets the key. More...
	setPassword ($password, $method='pbkdf2')
	Sets the password. More...
	encrypt ($plaintext)
	Encrypts a message. More...
	decrypt ($ciphertext)
	Decrypts a message. More...
	_openssl_ctr_process ($plaintext, &$encryptIV, &$buffer)
	OpenSSL CTR Processor. More...
	_openssl_ofb_process ($plaintext, &$encryptIV, &$buffer)
	OpenSSL OFB Processor. More...
	_openssl_translate_mode ()
	phpseclib <-> OpenSSL Mode Mapper More...
	enablePadding ()
	Pad "packets". More...
	disablePadding ()
	Do not pad packets. More...
	enableContinuousBuffer ()
	Treat consecutive "packets" as if they are a continuous buffer. More...
	disableContinuousBuffer ()
	Treat consecutive packets as if they are a discontinuous buffer. More...
	isValidEngine ($engine)
	Test for engine validity. More...
	setPreferredEngine ($engine)
	Sets the preferred crypt engine. More...
	getEngine ()
	Returns the engine currently being utilized. More...
	_setEngine ()
	Sets the engine as appropriate. More...
	_encryptBlock ($in)
	Encrypts a block. More...
	_decryptBlock ($in)
	Decrypts a block. More...
	_setupKey ()
	Setup the key (expansion) More...
	_setup ()
	Setup the self::ENGINE_INTERNAL $engine. More...
	_setupMcrypt ()
	Setup the self::ENGINE_MCRYPT $engine. More...
	_pad ($text)
	Pads a string. More...
	_unpad ($text)
	Unpads a string. More...
	_clearBuffers ()
	Clears internal buffers. More...
	_string_shift (&$string, $index=1)
	String Shift. More...
	_string_pop (&$string, $index=1)
	String Pop. More...
	_increment_str (&$var)
	Increment the current string. More...
	_setupInlineCrypt ()
	Setup the performance-optimized function for de/encrypt() More...
	_createInlineCryptFunction ($cipher_code)
	Creates the performance-optimized function for en/decrypt() More...
&	_getLambdaFunctions ()
	Holds the lambda_functions table (classwide) More...
	_hashInlineCryptFunction ($bytes)
	Generates a digest from $bytes. More...

Data Fields
	$block_size = 8
	$key
	$orig_key
	$skip_key_adjustment = true
	$key_length = 16
	$cipher_name_mcrypt = 'rc2'
	$cfb_init_len = 500
	$default_key_length = 1024
	$current_key_length
	$keys
	$pitable
	$invpitable
Data Fields inherited from phpseclib\Crypt\Base
const	MODE_CTR = -1
	#+ @access public More...
const	MODE_ECB = 1
	Encrypt / decrypt using the Electronic Code Book mode. More...
const	MODE_CBC = 2
	Encrypt / decrypt using the Code Book Chaining mode. More...
const	MODE_CFB = 3
	Encrypt / decrypt using the Cipher Feedback mode. More...
const	MODE_OFB = 4
	Encrypt / decrypt using the Output Feedback mode. More...
const	MODE_STREAM = 5
	Encrypt / decrypt using streaming mode. More...
const	ENGINE_INTERNAL = 1
	#+ @access private More...
const	ENGINE_MCRYPT = 2
	Base value for the mcrypt implementation $engine switch. More...
const	ENGINE_OPENSSL = 3
	Base value for the mcrypt implementation $engine switch. More...
	$mode
	$block_size = 16
	$key = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
	$iv
	$encryptIV
	$decryptIV
	$continuousBuffer = false
	$enbuffer
	$debuffer
	$enmcrypt
	$demcrypt
	$enchanged = true
	$dechanged = true
	$ecb
	$cfb_init_len = 600
	$changed = true
	$padding = true
	$paddable = false
	$engine
	$preferredEngine
	$cipher_name_mcrypt
	$cipher_name_openssl
	$cipher_name_openssl_ecb
	$password_default_salt = 'phpseclib/salt'
	$inline_crypt
	$use_inline_crypt
	$openssl_emulate_ctr = false
	$openssl_options
	$explicit_key_length = false
	$skip_key_adjustment = false

Additional Inherited Members
Static Public Attributes inherited from phpseclib\Crypt\Base
static	$WHIRLPOOL_AVAILABLE

Detailed Description

Definition at line 46 of file RC2.php.

Member Function Documentation

_decryptBlock()

phpseclib\Crypt\RC2::_decryptBlock

(

$in

)

Decrypts a block.

See also

\phpseclib\Crypt\Base::_decryptBlock()

\phpseclib\Crypt\Base::decrypt() @access private

Parameters

string

$in

Returns

string

Reimplemented from phpseclib\Crypt\Base.

Definition at line 475 of file RC2.php.

    {
        list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
        $keys = $this->keys;
        $limit = 44;
        $actions = array($limit => 20, 20 => 0);
        $j = 64;
 
        for (;;) {
            // R-mixing round.
            $r3 = ($r3 | ($r3 << 16)) >> 5;
            $r3 = ($r3 - $keys[--$j] - ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
            $r2 = ($r2 | ($r2 << 16)) >> 3;
            $r2 = ($r2 - $keys[--$j] - ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
            $r1 = ($r1 | ($r1 << 16)) >> 2;
            $r1 = ($r1 - $keys[--$j] - ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
            $r0 = ($r0 | ($r0 << 16)) >> 1;
            $r0 = ($r0 - $keys[--$j] - ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;
 
            if ($j === $limit) {
                if ($limit === 0) {
                    break;
                }
 
                // R-mashing round.
                $r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
                $r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
                $r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
                $r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;
                $limit = $actions[$limit];
            }
        }
 
        return pack('vvvv', $r0, $r1, $r2, $r3);
    }

References $in, and phpseclib\Crypt\RC2\$keys.

_encryptBlock()

phpseclib\Crypt\RC2::_encryptBlock

(

$in

)

Encrypts a block.

See also

\phpseclib\Crypt\Base::_encryptBlock()

\phpseclib\Crypt\Base::encrypt() @access private

Parameters

string

$in

Returns

string

Reimplemented from phpseclib\Crypt\Base.

Definition at line 430 of file RC2.php.

    {
        list($r0, $r1, $r2, $r3) = array_values(unpack('v*', $in));
        $keys = $this->keys;
        $limit = 20;
        $actions = array($limit => 44, 44 => 64);
        $j = 0;
 
        for (;;) {
            // Mixing round.
            $r0 = (($r0 + $keys[$j++] + ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
            $r0 |= $r0 >> 16;
            $r1 = (($r1 + $keys[$j++] + ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
            $r1 |= $r1 >> 16;
            $r2 = (($r2 + $keys[$j++] + ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
            $r2 |= $r2 >> 16;
            $r3 = (($r3 + $keys[$j++] + ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
            $r3 |= $r3 >> 16;
 
            if ($j === $limit) {
                if ($limit === 64) {
                    break;
                }
 
                // Mashing round.
                $r0 += $keys[$r3 & 0x3F];
                $r1 += $keys[$r0 & 0x3F];
                $r2 += $keys[$r1 & 0x3F];
                $r3 += $keys[$r2 & 0x3F];
                $limit = $actions[$limit];
            }
        }
 
        return pack('vvvv', $r0, $r1, $r2, $r3);
    }

References $in, and phpseclib\Crypt\RC2\$keys.

_setupInlineCrypt()

phpseclib\Crypt\RC2::_setupInlineCrypt

(

)

Setup the performance-optimized function for de/encrypt()

See also

\phpseclib\Crypt\Base::_setupInlineCrypt() @access private

Reimplemented from phpseclib\Crypt\Base.

Definition at line 553 of file RC2.php.

    {
        $lambda_functions =& self::_getLambdaFunctions();
 
        // The first 10 generated $lambda_functions will use the $keys hardcoded as integers
        // for the mixing rounds, for better inline crypt performance [~20% faster].
        // But for memory reason we have to limit those ultra-optimized $lambda_functions to an amount of 10.
        // (Currently, for Crypt_RC2, one generated $lambda_function cost on php5.5@32bit ~60kb unfreeable mem and ~100kb on php5.5@64bit)
        $gen_hi_opt_code = (bool)(count($lambda_functions) < 10);
 
        // Generation of a uniqe hash for our generated code
        $code_hash = "Crypt_RC2, {$this->mode}";
        if ($gen_hi_opt_code) {
            $code_hash = str_pad($code_hash, 32) . $this->_hashInlineCryptFunction($this->key);
        }
 
        // Is there a re-usable $lambda_functions in there?
        // If not, we have to create it.
        if (!isset($lambda_functions[$code_hash])) {
            // Init code for both, encrypt and decrypt.
            $init_crypt = '$keys = $self->keys;';
 
            switch (true) {
                case $gen_hi_opt_code:
                    $keys = $this->keys;
                default:
                    $keys = array();
                    foreach ($this->keys as $k => $v) {
                        $keys[$k] = '$keys[' . $k . ']';
                    }
            }
 
            // $in is the current 8 bytes block which has to be en/decrypt
            $encrypt_block = $decrypt_block = '
                $in = unpack("v4", $in);
                $r0 = $in[1];
                $r1 = $in[2];
                $r2 = $in[3];
                $r3 = $in[4];
            ';
 
            // Create code for encryption.
            $limit = 20;
            $actions = array($limit => 44, 44 => 64);
            $j = 0;
 
            for (;;) {
                // Mixing round.
                $encrypt_block .= '
                    $r0 = (($r0 + ' . $keys[$j++] . ' +
                           ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF) << 1;
                    $r0 |= $r0 >> 16;
                    $r1 = (($r1 + ' . $keys[$j++] . ' +
                           ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF) << 2;
                    $r1 |= $r1 >> 16;
                    $r2 = (($r2 + ' . $keys[$j++] . ' +
                           ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF) << 3;
                    $r2 |= $r2 >> 16;
                    $r3 = (($r3 + ' . $keys[$j++] . ' +
                           ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF) << 5;
                    $r3 |= $r3 >> 16;';
 
                if ($j === $limit) {
                    if ($limit === 64) {
                        break;
                    }
 
                    // Mashing round.
                    $encrypt_block .= '
                        $r0 += $keys[$r3 & 0x3F];
                        $r1 += $keys[$r0 & 0x3F];
                        $r2 += $keys[$r1 & 0x3F];
                        $r3 += $keys[$r2 & 0x3F];';
                    $limit = $actions[$limit];
                }
            }
 
            $encrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';
 
            // Create code for decryption.
            $limit = 44;
            $actions = array($limit => 20, 20 => 0);
            $j = 64;
 
            for (;;) {
                // R-mixing round.
                $decrypt_block .= '
                    $r3 = ($r3 | ($r3 << 16)) >> 5;
                    $r3 = ($r3 - ' . $keys[--$j] . ' -
                           ((($r0 ^ $r1) & $r2) ^ $r0)) & 0xFFFF;
                    $r2 = ($r2 | ($r2 << 16)) >> 3;
                    $r2 = ($r2 - ' . $keys[--$j] . ' -
                           ((($r3 ^ $r0) & $r1) ^ $r3)) & 0xFFFF;
                    $r1 = ($r1 | ($r1 << 16)) >> 2;
                    $r1 = ($r1 - ' . $keys[--$j] . ' -
                           ((($r2 ^ $r3) & $r0) ^ $r2)) & 0xFFFF;
                    $r0 = ($r0 | ($r0 << 16)) >> 1;
                    $r0 = ($r0 - ' . $keys[--$j] . ' -
                           ((($r1 ^ $r2) & $r3) ^ $r1)) & 0xFFFF;';
 
                if ($j === $limit) {
                    if ($limit === 0) {
                        break;
                    }
 
                    // R-mashing round.
                    $decrypt_block .= '
                        $r3 = ($r3 - $keys[$r2 & 0x3F]) & 0xFFFF;
                        $r2 = ($r2 - $keys[$r1 & 0x3F]) & 0xFFFF;
                        $r1 = ($r1 - $keys[$r0 & 0x3F]) & 0xFFFF;
                        $r0 = ($r0 - $keys[$r3 & 0x3F]) & 0xFFFF;';
                    $limit = $actions[$limit];
                }
            }
 
            $decrypt_block .= '$in = pack("v4", $r0, $r1, $r2, $r3);';
 
            // Creates the inline-crypt function
            $lambda_functions[$code_hash] = $this->_createInlineCryptFunction(
                array(
                   'init_crypt'    => $init_crypt,
                   'encrypt_block' => $encrypt_block,
                   'decrypt_block' => $decrypt_block
                )
            );
        }
 
        // Set the inline-crypt function as callback in: $this->inline_crypt
        $this->inline_crypt = $lambda_functions[$code_hash];
    }

References phpseclib\Crypt\RC2\$keys, phpseclib\Crypt\Base\_createInlineCryptFunction(), phpseclib\Crypt\Base\_getLambdaFunctions(), and phpseclib\Crypt\Base\_hashInlineCryptFunction().

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_setupKey()

phpseclib\Crypt\RC2::_setupKey

(

)

Creates the key schedule.

See also

\phpseclib\Crypt\Base::_setupKey() @access private

Reimplemented from phpseclib\Crypt\Base.

Definition at line 532 of file RC2.php.

    {
        if (!isset($this->key)) {
            $this->setKey('');
        }
 
        // Key has already been expanded in \phpseclib\Crypt\RC2::setKey():
        // Only the first value must be altered.
        $l = unpack('Ca/Cb/v*', $this->key);
        array_unshift($l, $this->pitable[$l['a']] | ($l['b'] << 8));
        unset($l['a']);
        unset($l['b']);
        $this->keys = $l;
    }

References $l, and phpseclib\Crypt\RC2\setKey().

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_setupMcrypt()

phpseclib\Crypt\RC2::_setupMcrypt

(

)

Setup the \phpseclib\Crypt\Base::ENGINE_MCRYPT $engine.

See also

\phpseclib\Crypt\Base::_setupMcrypt() @access private

Reimplemented from phpseclib\Crypt\Base.

Definition at line 517 of file RC2.php.

    {
        if (!isset($this->key)) {
            $this->setKey('');
        }
 
        parent::_setupMcrypt();
    }

References phpseclib\Crypt\RC2\setKey().

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decrypt()

phpseclib\Crypt\RC2::decrypt

(

$ciphertext

)

Decrypts a message.

Mostly a wrapper for \phpseclib\Crypt\Base::decrypt, with some additional OpenSSL handling code

See also

self::encrypt() @access User interface

Parameters

string

$ciphertext

Returns

string $plaintext

Reimplemented from phpseclib\Crypt\Base.

Definition at line 408 of file RC2.php.

    {
        if ($this->engine == self::ENGINE_OPENSSL) {
            $temp = $this->key;
            $this->key = $this->orig_key;
            $result = parent::decrypt($ciphertext);
            $this->key = $temp;
            return $result;
        }
 
        return parent::encrypt($ciphertext);
    }

References phpseclib\Crypt\RC2\$key, phpseclib\Crypt\RC2\$orig_key, and $result.

encrypt()

phpseclib\Crypt\RC2::encrypt

(

$plaintext

)

Encrypts a message.

Mostly a wrapper for \phpseclib\Crypt\Base::encrypt, with some additional OpenSSL handling code

See also

self::decrypt() @access User interface

Parameters

string

$plaintext

Returns

string $ciphertext

Reimplemented from phpseclib\Crypt\Base.

Definition at line 385 of file RC2.php.

    {
        if ($this->engine == self::ENGINE_OPENSSL) {
            $temp = $this->key;
            $this->key = $this->orig_key;
            $result = parent::encrypt($plaintext);
            $this->key = $temp;
            return $result;
        }
 
        return parent::encrypt($plaintext);
    }

References phpseclib\Crypt\RC2\$key, phpseclib\Crypt\RC2\$orig_key, and $result.

getKeyLength()

phpseclib\Crypt\RC2::getKeyLength

(

)

Returns the current key length.

@access public

Returns

int

Reimplemented from phpseclib\Crypt\Base.

Definition at line 311 of file RC2.php.

    {
        return $this->current_key_length;
    }

References phpseclib\Crypt\RC2\$current_key_length.

isValidEngine()

phpseclib\Crypt\RC2::isValidEngine

(

$engine

)

Test for engine validity.

This is mainly just a wrapper to set things up for \phpseclib\Crypt\Base::isValidEngine()

See also

\phpseclib\Crypt\Base::__construct()

Parameters

int

$engine

@access public

Returns

bool

Reimplemented from phpseclib\Crypt\Base.

Definition at line 274 of file RC2.php.

    {
        switch ($engine) {
            case self::ENGINE_OPENSSL:
                if ($this->current_key_length != 128 || strlen($this->orig_key) < 16) {
                    return false;
                }
                $this->cipher_name_openssl_ecb = 'rc2-ecb';
                $this->cipher_name_openssl = 'rc2-' . $this->_openssl_translate_mode();
        }
 
        return parent::isValidEngine($engine);
    }

References phpseclib\Crypt\Base\$engine, phpseclib\Crypt\Base\_openssl_translate_mode(), and phpseclib\Crypt\Base\ENGINE_OPENSSL.

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setKey()

phpseclib\Crypt\RC2::setKey	(		$key,
			$t1 = 0
	)

Sets the key.

Keys can be of any length. RC2, itself, uses 1 to 1024 bit keys (eg. strlen($key) <= 128), however, we only use the first 128 bytes if $key has more then 128 bytes in it, and set $key to a single null byte if it is empty.

If the key is not explicitly set, it'll be assumed to be a single null byte.

See also

\phpseclib\Crypt\Base::setKey() @access User interface

Parameters

string	$key
int	$t1	optional Effective key length in bits.

Definition at line 332 of file RC2.php.

    {
        $this->orig_key = $key;
 
        if ($t1 <= 0) {
            $t1 = $this->default_key_length;
        } elseif ($t1 > 1024) {
            $t1 = 1024;
        }
        $this->current_key_length = $t1;
        // Key byte count should be 1..128.
        $key = strlen($key) ? substr($key, 0, 128) : "\x00";
        $t = strlen($key);
 
        // The mcrypt RC2 implementation only supports effective key length
        // of 1024 bits. It is however possible to handle effective key
        // lengths in range 1..1024 by expanding the key and applying
        // inverse pitable mapping to the first byte before submitting it
        // to mcrypt.
 
        // Key expansion.
        $l = array_values(unpack('C*', $key));
        $t8 = ($t1 + 7) >> 3;
        $tm = 0xFF >> (8 * $t8 - $t1);
 
        // Expand key.
        $pitable = $this->pitable;
        for ($i = $t; $i < 128; $i++) {
            $l[$i] = $pitable[$l[$i - 1] + $l[$i - $t]];
        }
        $i = 128 - $t8;
        $l[$i] = $pitable[$l[$i] & $tm];
        while ($i--) {
            $l[$i] = $pitable[$l[$i + 1] ^ $l[$i + $t8]];
        }
 
        // Prepare the key for mcrypt.
        $l[0] = $this->invpitable[$l[0]];
        array_unshift($l, 'C*');
 
        parent::setKey(call_user_func_array('pack', $l));
    }

References phpseclib\Crypt\RC2\$default_key_length, $i, phpseclib\Crypt\RC2\$key, $l, phpseclib\Crypt\RC2\$pitable, and $t.

Referenced by phpseclib\Crypt\RC2\_setupKey(), and phpseclib\Crypt\RC2\_setupMcrypt().

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setKeyLength()

phpseclib\Crypt\RC2::setKeyLength

(

$length

)

Sets the key length.

Valid key lengths are 1 to 1024. Calling this function after setting the key has no effect until the next \phpseclib\Crypt\RC2::setKey() call.

@access public

Parameters

int

$length

in bits

Reimplemented from phpseclib\Crypt\Base.

Definition at line 298 of file RC2.php.

    {
        if ($length >= 1 && $length <= 1024) {
            $this->default_key_length = $length;
        }
    }

Field Documentation

$block_size

phpseclib\Crypt\RC2::$block_size = 8

Definition at line 55 of file RC2.php.

$cfb_init_len

phpseclib\Crypt\RC2::$cfb_init_len = 500

Definition at line 113 of file RC2.php.

$cipher_name_mcrypt

phpseclib\Crypt\RC2::$cipher_name_mcrypt = 'rc2'

Definition at line 104 of file RC2.php.

$current_key_length

phpseclib\Crypt\RC2::$current_key_length

Definition at line 136 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\getKeyLength().

$default_key_length

phpseclib\Crypt\RC2::$default_key_length = 1024

Definition at line 125 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\setKey().

$invpitable

phpseclib\Crypt\RC2::$invpitable

Definition at line 229 of file RC2.php.

$key

phpseclib\Crypt\RC2::$key

Definition at line 65 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\decrypt(), phpseclib\Crypt\RC2\encrypt(), and phpseclib\Crypt\RC2\setKey().

$key_length

phpseclib\Crypt\RC2::$key_length = 16

Definition at line 95 of file RC2.php.

$keys

phpseclib\Crypt\RC2::$keys

Definition at line 145 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\_decryptBlock(), phpseclib\Crypt\RC2\_encryptBlock(), and phpseclib\Crypt\RC2\_setupInlineCrypt().

$orig_key

phpseclib\Crypt\RC2::$orig_key

Definition at line 77 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\decrypt(), and phpseclib\Crypt\RC2\encrypt().

$pitable

phpseclib\Crypt\RC2::$pitable

Definition at line 155 of file RC2.php.

Referenced by phpseclib\Crypt\RC2\setKey().

$skip_key_adjustment

phpseclib\Crypt\RC2::$skip_key_adjustment = true

Definition at line 86 of file RC2.php.

---

The documentation for this class was generated from the following file:

• libs/composer/vendor/phpseclib/phpseclib/phpseclib/Crypt/RC2.php