PHP Classes

File: src/Core/HChaCha20.php

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  Classes of Scott Arciszewski   PHP Sodium Compat   src/Core/HChaCha20.php   Download  
File: src/Core/HChaCha20.php
Role: Class source
Content type: text/plain
Description: Class source
Class: PHP Sodium Compat
Cryptographic functions of libsodium in pure PHP
Author: By
Last change: Update docblocks.
Date: 6 years ago
Size: 3,871 bytes
 

Contents

Class file image Download
<?php

if (class_exists('ParagonIE_Sodium_Core_HChaCha20', false)) {
    return;
}

/**
 * Class ParagonIE_Sodium_Core_HChaCha20
 */
class ParagonIE_Sodium_Core_HChaCha20 extends ParagonIE_Sodium_Core_ChaCha20
{
   
/**
     * @param string $in
     * @param string $key
     * @param string|null $c
     * @return string
     * @throws TypeError
     */
   
public static function hChaCha20($in = '', $key = '', $c = null)
    {
       
$ctx = array();

        if (
$c === null) {
           
$ctx[0] = 0x61707865;
           
$ctx[1] = 0x3320646e;
           
$ctx[2] = 0x79622d32;
           
$ctx[3] = 0x6b206574;
        } else {
           
$ctx[0] = self::load_4(self::substr($c, 0, 4));
           
$ctx[1] = self::load_4(self::substr($c, 4, 4));
           
$ctx[2] = self::load_4(self::substr($c, 8, 4));
           
$ctx[3] = self::load_4(self::substr($c, 12, 4));
        }
       
$ctx[4] = self::load_4(self::substr($key, 0, 4));
       
$ctx[5] = self::load_4(self::substr($key, 4, 4));
       
$ctx[6] = self::load_4(self::substr($key, 8, 4));
       
$ctx[7] = self::load_4(self::substr($key, 12, 4));
       
$ctx[8] = self::load_4(self::substr($key, 16, 4));
       
$ctx[9] = self::load_4(self::substr($key, 20, 4));
       
$ctx[10] = self::load_4(self::substr($key, 24, 4));
       
$ctx[11] = self::load_4(self::substr($key, 28, 4));
       
$ctx[12] = self::load_4(self::substr($in, 0, 4));
       
$ctx[13] = self::load_4(self::substr($in, 4, 4));
       
$ctx[14] = self::load_4(self::substr($in, 8, 4));
       
$ctx[15] = self::load_4(self::substr($in, 12, 4));
        return
self::hChaCha20Bytes($ctx);
    }

   
/**
     * @param array $ctx
     * @return string
     * @throws TypeError
     */
   
protected static function hChaCha20Bytes(array $ctx)
    {
       
$x0 = (int) $ctx[0];
       
$x1 = (int) $ctx[1];
       
$x2 = (int) $ctx[2];
       
$x3 = (int) $ctx[3];
       
$x4 = (int) $ctx[4];
       
$x5 = (int) $ctx[5];
       
$x6 = (int) $ctx[6];
       
$x7 = (int) $ctx[7];
       
$x8 = (int) $ctx[8];
       
$x9 = (int) $ctx[9];
       
$x10 = (int) $ctx[10];
       
$x11 = (int) $ctx[11];
       
$x12 = (int) $ctx[12];
       
$x13 = (int) $ctx[13];
       
$x14 = (int) $ctx[14];
       
$x15 = (int) $ctx[15];

        for (
$i = 0; $i < 10; ++$i) {
           
# QUARTERROUND( x0, x4, x8, x12)
           
list($x0, $x4, $x8, $x12) = self::quarterRound($x0, $x4, $x8, $x12);

           
# QUARTERROUND( x1, x5, x9, x13)
           
list($x1, $x5, $x9, $x13) = self::quarterRound($x1, $x5, $x9, $x13);

           
# QUARTERROUND( x2, x6, x10, x14)
           
list($x2, $x6, $x10, $x14) = self::quarterRound($x2, $x6, $x10, $x14);

           
# QUARTERROUND( x3, x7, x11, x15)
           
list($x3, $x7, $x11, $x15) = self::quarterRound($x3, $x7, $x11, $x15);

           
# QUARTERROUND( x0, x5, x10, x15)
           
list($x0, $x5, $x10, $x15) = self::quarterRound($x0, $x5, $x10, $x15);

           
# QUARTERROUND( x1, x6, x11, x12)
           
list($x1, $x6, $x11, $x12) = self::quarterRound($x1, $x6, $x11, $x12);

           
# QUARTERROUND( x2, x7, x8, x13)
           
list($x2, $x7, $x8, $x13) = self::quarterRound($x2, $x7, $x8, $x13);

           
# QUARTERROUND( x3, x4, x9, x14)
           
list($x3, $x4, $x9, $x14) = self::quarterRound($x3, $x4, $x9, $x14);
        }

        return
self::store32_le((int) ($x0 & 0xffffffff)) .
           
self::store32_le((int) ($x1 & 0xffffffff)) .
           
self::store32_le((int) ($x2 & 0xffffffff)) .
           
self::store32_le((int) ($x3 & 0xffffffff)) .
           
self::store32_le((int) ($x12 & 0xffffffff)) .
           
self::store32_le((int) ($x13 & 0xffffffff)) .
           
self::store32_le((int) ($x14 & 0xffffffff)) .
           
self::store32_le((int) ($x15 & 0xffffffff));
    }
}