TripleDES

Pure-PHP implementation of Triple DES.

• Full name: \phpseclib\Crypt\TripleDES
• Parent class: \phpseclib\Crypt\DES

Constants

Constant	Visibility	Type	Value
MODE_3CBC	public		-2
MODE_CBC3	public		self::MODE_CBC

Properties

key_length

Key Length (in bytes)

public int $key_length

See Also:

• \phpseclib\Crypt\TripleDES::setKeyLength() -

---

password_default_salt

The default salt used by setPassword()

public string $password_default_salt

See Also:

• \phpseclib\Crypt\Base::password_default_salt - * \phpseclib\Crypt\Base::setPassword() -

---

cipher_name_mcrypt

The mcrypt specific name of the cipher

public string $cipher_name_mcrypt

See Also:

• \phpseclib\Crypt\DES::cipher_name_mcrypt - * \phpseclib\Crypt\Base::cipher_name_mcrypt -

---

cfb_init_len

Optimizing value while CFB-encrypting

public int $cfb_init_len

See Also:

• \phpseclib\Crypt\Base::cfb_init_len -

---

key_length_max

max possible size of $key

public string $key_length_max

See Also:

• \phpseclib\Crypt\self::setKey() - * \phpseclib\Crypt\DES::setKey() -

---

mode_3cbc

Internal flag whether using self::MODE_3CBC or not

public bool $mode_3cbc

---

des

The \phpseclib\Crypt\DES objects

public array $des

Used only if $mode_3cbc === true

---

Methods

__construct

Default Constructor.

public __construct(int $mode = self::MODE_CBC): mixed

Determines whether or not the mcrypt extension should be used.

$mode could be:

• \phpseclib\Crypt\Base::MODE_ECB

• \phpseclib\Crypt\Base::MODE_CBC

• \phpseclib\Crypt\Base::MODE_CTR

• \phpseclib\Crypt\Base::MODE_CFB

• \phpseclib\Crypt\Base::MODE_OFB

• \phpseclib\Crypt\TripleDES::MODE_3CBC

If not explicitly set, \phpseclib\Crypt\Base::MODE_CBC will be used.

Parameters:

Parameter	Type	Description
$mode	int

See Also:

• \phpseclib\Crypt\DES::__construct() - * \phpseclib\Crypt\Base::__construct() -

---

isValidEngine

Test for engine validity

public isValidEngine(int $engine): bool

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

Parameters:

Parameter	Type	Description
$engine	int

See Also:

• \phpseclib\Crypt\Base::__construct() -

---

setIV

Sets the initialization vector. (optional)

public setIV(string $iv): mixed

SetIV is not required when \phpseclib\Crypt\Base::MODE_ECB is being used. If not explicitly set, it'll be assumed to be all zero's.

Parameters:

Parameter	Type	Description
$iv	string

See Also:

• \phpseclib\Crypt\Base::setIV() -

---

setKeyLength

Sets the key length.

public setKeyLength(int $length): mixed

Valid key lengths are 64, 128 and 192

Parameters:

Parameter	Type	Description
$length	int

See Also:

• • \phpseclib\Crypt\Base:setKeyLength()

---

setKey

Sets the key.

public setKey(string $key): mixed

Keys can be of any length. Triple DES, itself, can use 128-bit (eg. strlen($key) == 16) or 192-bit (eg. strlen($key) == 24) keys. This function pads and truncates $key as appropriate.

DES also requires that every eighth bit be a parity bit, however, we'll ignore that.

If the key is not explicitly set, it'll be assumed to be all null bytes.

Parameters:

Parameter	Type	Description
$key	string

See Also:

• \phpseclib\Crypt\DES::setKey() - * \phpseclib\Crypt\Base::setKey() -

---

encrypt

Encrypts a message.

public encrypt(string $plaintext): string

Parameters:

Parameter	Type	Description
$plaintext	string

Return Value:

$cipertext

See Also:

• \phpseclib\Crypt\Base::encrypt() -

---

decrypt

Decrypts a message.

public decrypt(string $ciphertext): string

Parameters:

Parameter	Type	Description
$ciphertext	string

Return Value:

$plaintext

See Also:

• \phpseclib\Crypt\Base::decrypt() -

---

enableContinuousBuffer

Treat consecutive "packets" as if they are a continuous buffer.

public enableContinuousBuffer(): mixed

Say you have a 16-byte plaintext $plaintext. Using the default behavior, the two following code snippets will yield different outputs:

echo $des->encrypt(substr($plaintext, 0, 8)); echo $des->encrypt(substr($plaintext, 8, 8)); echo $des->encrypt($plaintext);

The solution is to enable the continuous buffer. Although this will resolve the above discrepancy, it creates another, as demonstrated with the following:

$des->encrypt(substr($plaintext, 0, 8)); echo $des->decrypt($des->encrypt(substr($plaintext, 8, 8))); echo $des->decrypt($des->encrypt(substr($plaintext, 8, 8)));

With the continuous buffer disabled, these would yield the same output. With it enabled, they yield different outputs. The reason is due to the fact that the initialization vector's change after every encryption / decryption round when the continuous buffer is enabled. When it's disabled, they remain constant.

Put another way, when the continuous buffer is enabled, the state of the \phpseclib\Crypt\DES() object changes after each encryption / decryption round, whereas otherwise, it'd remain constant. For this reason, it's recommended that continuous buffers not be used. They do offer better security and are, in fact, sometimes required (SSH uses them), however, they are also less intuitive and more likely to cause you problems.

See Also:

• \phpseclib\Crypt\Base::enableContinuousBuffer() - * \phpseclib\Crypt\self::disableContinuousBuffer() -

---

disableContinuousBuffer

Treat consecutive packets as if they are a discontinuous buffer.

public disableContinuousBuffer(): mixed

The default behavior.

See Also:

• \phpseclib\Crypt\Base::disableContinuousBuffer() - * \phpseclib\Crypt\self::enableContinuousBuffer() -

---

_setupKey

Creates the key schedule

public _setupKey(): mixed

See Also:

• \phpseclib\Crypt\DES::_setupKey() - * \phpseclib\Crypt\Base::_setupKey() -

---

setPreferredEngine

Sets the internal crypt engine

public setPreferredEngine(int $engine): int

Parameters:

Parameter	Type	Description
$engine	int

See Also:

• \phpseclib\Crypt\Base::__construct() - * \phpseclib\Crypt\Base::setPreferredEngine() -

---

Inherited methods

__construct

Default Constructor.

public __construct(int $mode = self::MODE_CBC): mixed

Determines whether or not the mcrypt extension should be used.

$mode could be:

• self::MODE_ECB

• self::MODE_CBC

• self::MODE_CTR

• self::MODE_CFB

• self::MODE_OFB

If not explicitly set, self::MODE_CBC will be used.

Parameters:

Parameter	Type	Description
$mode	int

---

setKeyLength

Sets the key length.

public setKeyLength(int $length): mixed

Keys with explicitly set lengths need to be treated accordingly

Parameters:

Parameter	Type	Description
$length	int

---

getKeyLength

Returns the current key length in bits

public getKeyLength(): int

---

getBlockLength

Returns the current block length in bits

public getBlockLength(): int

---

_openssl_ctr_process

OpenSSL CTR Processor

public _openssl_ctr_process(string $plaintext, string& $encryptIV, array& $buffer): string

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 Base::encrypt() and Base::decrypt(). Also, OpenSSL doesn't implement CTR for all of it's symmetric ciphers so this function will emulate CTR with ECB when necessary.

Parameters:

Parameter	Type	Description
$plaintext	string
$encryptIV	string
$buffer	array

See Also:

• \phpseclib\Crypt\self::encrypt() - * \phpseclib\Crypt\self::decrypt() -

---

_openssl_ofb_process

OpenSSL OFB Processor

public _openssl_ofb_process(string $plaintext, string& $encryptIV, array& $buffer): string

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 Base::encrypt() and Base::decrypt().

Parameters:

Parameter	Type	Description
$plaintext	string
$encryptIV	string
$buffer	array

See Also:

• \phpseclib\Crypt\self::encrypt() - * \phpseclib\Crypt\self::decrypt() -

---

_openssl_translate_mode

phpseclib <-> OpenSSL Mode Mapper

public _openssl_translate_mode(): int

May need to be overwritten by classes extending this one in some cases

---

enablePadding

Pad "packets".

public enablePadding(): mixed

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 Also:

• \phpseclib\Crypt\self::disablePadding() -

---

disablePadding

Do not pad packets.

public disablePadding(): mixed

See Also:

• \phpseclib\Crypt\self::enablePadding() -

---

isValidEngine

Test for engine validity

public isValidEngine(int $engine): bool

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

Parameters:

Parameter	Type	Description
$engine	int

See Also:

• \phpseclib\Crypt\Base::isValidEngine() -

---

setPreferredEngine

Sets the preferred crypt engine

public setPreferredEngine(int $engine): mixed

Currently, $engine could be:

• \phpseclib\Crypt\Base::ENGINE_OPENSSL [very fast]

• \phpseclib\Crypt\Base::ENGINE_MCRYPT [fast]

• \phpseclib\Crypt\Base::ENGINE_INTERNAL [slow]

If the preferred crypt engine is not available the fastest available one will be used

Parameters:

Parameter	Type	Description
$engine	int

See Also:

• \phpseclib\Crypt\self::__construct() -

---

getEngine

Returns the engine currently being utilized

public getEngine(): mixed

See Also:

• \phpseclib\Crypt\self::_setEngine() -

---

_setEngine

Sets the engine as appropriate

public _setEngine(): mixed

See Also:

• \phpseclib\Crypt\self::__construct() -

---

_encryptBlock

Encrypts a block

public _encryptBlock(string $in): string

Parameters:

Parameter	Type	Description
$in	string

See Also:

• \phpseclib\Crypt\Base::_encryptBlock() - * \phpseclib\Crypt\Base::encrypt() - * \phpseclib\Crypt\self::encrypt() -

---

_decryptBlock

Decrypts a block

public _decryptBlock(string $in): string

Parameters:

Parameter	Type	Description
$in	string

See Also:

• \phpseclib\Crypt\Base::_decryptBlock() - * \phpseclib\Crypt\Base::decrypt() - * \phpseclib\Crypt\self::decrypt() -

---

_setupKey

Creates the key schedule

public _setupKey(): mixed

See Also:

• \phpseclib\Crypt\Base::_setupKey() -

---

_pad

Pads a string

public _pad(string $text): 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.

Parameters:

Parameter	Type	Description
$text	string

See Also:

• \phpseclib\Crypt\self::_unpad() -

---

_unpad

Unpads a string.

public _unpad(string $text): 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.

Parameters:

Parameter	Type	Description
$text	string

See Also:

• \phpseclib\Crypt\self::_pad() -

---

_string_shift

String Shift

public _string_shift(string& $string, int $index = 1): string

Inspired by array_shift

Parameters:

Parameter	Type	Description
$string	string
$index	int

---

_string_pop

String Pop

public _string_pop(string& $string, int $index = 1): string

Inspired by array_pop

Parameters:

Parameter	Type	Description
$string	string
$index	int

---

_increment_str

Increment the current string

public _increment_str(string& $var): mixed

Parameters:

Parameter	Type	Description
$var	string

See Also:

• \phpseclib\Crypt\self::decrypt() - * \phpseclib\Crypt\self::encrypt() -

---

_createInlineCryptFunction

Creates the performance-optimized function for en/decrypt()

public _createInlineCryptFunction(array $cipher_code): string

Internally for phpseclib developers:

_createInlineCryptFunction():

• merge the $cipher_code [setup'ed by _setupInlineCrypt()] with the current [$this->]mode of operation code

• create the $inline function, which called by encrypt() / decrypt() as its replacement to speed up the en/decryption operations.

• return the name of the created $inline callback function

• used to speed up en/decryption

The main reason why can speed up things [up to 50%] this way are:

• using variables more effective then regular. (ie no use of expensive arrays but integers $k_0, $k_1 ... or even, for example, the pure $key[] values hardcoded)

• avoiding 1000's of function calls of ie _encryptBlock() but inlining the crypt operations. in the mode of operation for() loop.

• full loop unroll the (sometimes key-dependent) rounds avoiding this way ++$i counters and runtime-if's etc...

The basic code architectur of the generated $inline en/decrypt() lambda function, in pseudo php, is:

+----------------------------------------------------------------------------------------------+ | callback $inline = create_function: | | lambda_function_0001_crypt_ECB($action, $text) | | { | | INSERT PHP CODE OF: | | $cipher_code['init_crypt']; // general init code. | | // ie: $sbox'es declarations used for | | // encrypt and decrypt'ing. | | | | switch ($action) { | | case 'encrypt': | | INSERT PHP CODE OF: | | $cipher_code['init_encrypt']; // encrypt sepcific init code. | | ie: specified $key or $box | | declarations for encrypt'ing. | | | | foreach ($ciphertext) { | | $in = $block_size of $ciphertext; | | | | INSERT PHP CODE OF: | | $cipher_code['encrypt_block']; // encrypt's (string) $in, which is always: | | // strlen($in) == $this->block_size | | // here comes the cipher algorithm in action | | // for encryption. | | // $cipher_code['encrypt_block'] has to | | // encrypt the content of the $in variable | | | | $plaintext .= $in; | | } | | return $plaintext; | | | | case 'decrypt': | | INSERT PHP CODE OF: | | $cipher_code['init_decrypt']; // decrypt sepcific init code | | ie: specified $key or $box | | declarations for decrypt'ing. | | foreach ($plaintext) { | | $in = $block_size of $plaintext; | | | | INSERT PHP CODE OF: | | $cipher_code['decrypt_block']; // decrypt's (string) $in, which is always | | // strlen($in) == $this->block_size | | // here comes the cipher algorithm in action | | // for decryption. | | // $cipher_code['decrypt_block'] has to | | // decrypt the content of the $in variable | | $ciphertext .= $in; | | } | | return $ciphertext; | | } | | } | +----------------------------------------------------------------------------------------------+

See also the \phpseclib\Crypt*::_setupInlineCrypt()'s for productive inline $cipher_code's how they works.

Structure of: $cipher_code = array( 'init_crypt' => (string) '', // optional 'init_encrypt' => (string) '', // optional 'init_decrypt' => (string) '', // optional 'encrypt_block' => (string) '', // required 'decrypt_block' => (string) '' // required );

Parameters:

Parameter	Type	Description
$cipher_code	array

Return Value:

(the name of the created callback function)

See Also:

• \phpseclib\Crypt\self::_setupInlineCrypt() - * \phpseclib\Crypt\self::encrypt() - * \phpseclib\Crypt\self::decrypt() -

---

_getLambdaFunctions

Holds the lambda_functions table (classwide)

public _getLambdaFunctions(): array

Each name of the lambda function, created from _setupInlineCrypt() && _createInlineCryptFunction() is stored, classwide (!), here for reusing.

The string-based index of $function is a classwide unique value representing, at least, the $mode of operation (or more... depends of the optimizing level) for which $mode the lambda function was created.

Return Value:

&$functions

---

_hashInlineCryptFunction

Generates a digest from $bytes

public _hashInlineCryptFunction(string $bytes): string

Parameters:

Parameter	Type	Description
$bytes	string

See Also:

• \phpseclib\Crypt\self::_setupInlineCrypt() -

---

safe_intval

Convert float to int

public safe_intval(string $x): int

On ARM CPUs converting floats to ints doesn't always work

Parameters:

Parameter	Type	Description
$x	string

---

safe_intval_inline

eval()'able string for in-line float to int

public safe_intval_inline(): string

---

do_nothing

Dummy error handler to suppress mcrypt errors

public do_nothing(): mixed

---

continuousBufferEnabled

Is the continuous buffer enabled?

public continuousBufferEnabled(): bool

---

setKey

Sets the key.

public setKey(string $key): mixed

Keys can be of any length. DES, itself, uses 64-bit keys (eg. strlen($key) == 8), however, we only use the first eight, if $key has more then eight characters in it, and pad $key with the null byte if it is less then eight characters long.

DES also requires that every eighth bit be a parity bit, however, we'll ignore that.

If the key is not explicitly set, it'll be assumed to be all zero's.

Parameters:

Parameter	Type	Description
$key	string

See Also:

• \phpseclib\Crypt\Base::setKey() -

---

_processBlock

Encrypts or decrypts a 64-bit block

public _processBlock(string $block, int $mode): string

$mode should be either self::ENCRYPT or self::DECRYPT. See {@link http://en.wikipedia.org/wiki/Image:Feistel.png} to get a general idea of what this function does.

Parameters:

Parameter	Type	Description
$block	string
$mode	int

See Also:

• \phpseclib\Crypt\self::_encryptBlock() - * \phpseclib\Crypt\self::_decryptBlock() -

---

_setupInlineCrypt

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

public _setupInlineCrypt(): mixed

See Also:

• \phpseclib\Crypt\Base::_setupInlineCrypt() -

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Automatically generated on 2025-03-18