PHP Classes
elePHPant
Icontem

File: src/Core/SipHash.php

Recommend this page to a friend!
  Classes of Scott Arciszewski  >  PHP Sodium Compat  >  src/Core/SipHash.php  >  Download  
File: src/Core/SipHash.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: Fix type assertions
Date: 6 months ago
Size: 8,026 bytes
 

Contents

Class file image Download
<?php

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

/**
 * Class ParagonIE_SodiumCompat_Core_SipHash
 *
 * Only uses 32-bit arithmetic, while the original SipHash used 64-bit integers
 */
class ParagonIE_Sodium_Core_SipHash extends ParagonIE_Sodium_Core_Util
{
   
/**
     * @internal You should not use this directly from another application
     *
     * @param int[] $v
     * @return int[]
     */
   
public static function sipRound(array $v)
    {
       
# v0 += v1;
       
list($v[0], $v[1]) = self::add(
            array(
$v[0], $v[1]),
            array(
$v[2], $v[3])
        );

       
# v1=ROTL(v1,13);
       
list($v[2], $v[3]) = self::rotl_64($v[2], $v[3], 13);

       
# v1 ^= v0;
       
$v[2] ^= $v[0];
       
$v[3] ^= $v[1];

       
# v0=ROTL(v0,32);
       
list($v[0], $v[1]) = self::rotl_64((int) $v[0], (int) $v[1], 32);

       
# v2 += v3;
       
list($v[4], $v[5]) = self::add(
            array(
$v[4], $v[5]),
            array(
$v[6], $v[7])
        );

       
# v3=ROTL(v3,16);
       
list($v[6], $v[7]) = self::rotl_64($v[6], $v[7], 16);

       
# v3 ^= v2;
       
$v[6] ^= $v[4];
       
$v[7] ^= $v[5];

       
# v0 += v3;
       
list($v[0], $v[1]) = self::add(
            array((int)
$v[0], (int) $v[1]),
            array((int)
$v[6], (int) $v[7])
        );

       
# v3=ROTL(v3,21);
       
list($v[6], $v[7]) = self::rotl_64((int) $v[6], (int) $v[7], 21);

       
# v3 ^= v0;
       
$v[6] ^= $v[0];
       
$v[7] ^= $v[1];

       
# v2 += v1;
       
list($v[4], $v[5]) = self::add(
            array((int)
$v[4], (int) $v[5]),
            array((int)
$v[2], (int) $v[3])
        );

       
# v1=ROTL(v1,17);
       
list($v[2], $v[3]) = self::rotl_64((int) $v[2], (int) $v[3], 17);

       
# v1 ^= v2;;
       
$v[2] ^= $v[4];
       
$v[3] ^= $v[5];

       
# v2=ROTL(v2,32)
       
list($v[4], $v[5]) = self::rotl_64((int) $v[4], (int) $v[5], 32);

        return
$v;
    }

   
/**
     * Add two 32 bit integers representing a 64-bit integer.
     *
     * @internal You should not use this directly from another application
     *
     * @param int[] $a
     * @param int[] $b
     * @return array<int, mixed>
     */
   
public static function add(array $a, array $b)
    {
       
/** @var int $x1 */
       
$x1 = $a[1] + $b[1];
       
/** @var int $c */
       
$c = $x1 >> 32; // Carry if ($a + $b) > 0xffffffff
        /** @var int $x0 */
       
$x0 = $a[0] + $b[0] + $c;
        return array(
           
$x0 & 0xffffffff,
           
$x1 & 0xffffffff
       
);
    }

   
/**
     * @internal You should not use this directly from another application
     *
     * @param int $int0
     * @param int $int1
     * @param int $c
     * @return array<int, mixed>
     */
   
public static function rotl_64($int0, $int1, $c)
    {
       
$int0 &= 0xffffffff;
       
$int1 &= 0xffffffff;
       
$c &= 63;
        if (
$c === 32) {
            return array(
$int1, $int0);
        }
        if (
$c > 31) {
           
$tmp = $int1;
           
$int1 = $int0;
           
$int0 = $tmp;
           
$c &= 31;
        }
        if (
$c === 0) {
            return array(
$int0, $int1);
        }
        return array(
           
0xffffffff & (
                (
$int0 << $c)
                    |
                (
$int1 >> (32 - $c))
            ),
           
0xffffffff & (
                (
$int1 << $c)
                    |
                (
$int0 >> (32 - $c))
            ),
        );
    }

   
/**
     * Implements Siphash-2-4 using only 32-bit numbers.
     *
     * When we split an int into two, the higher bits go to the lower index.
     * e.g. 0xDEADBEEFAB10C92D becomes [
     * 0 => 0xDEADBEEF,
     * 1 => 0xAB10C92D
     * ].
     *
     * @internal You should not use this directly from another application
     *
     * @param string $in
     * @param string $key
     * @return string
     * @throws SodiumException
     * @throws TypeError
     */
   
public static function sipHash24($in, $key)
    {
       
$inlen = self::strlen($in);

       
# /* "somepseudorandomlygeneratedbytes" */
        # u64 v0 = 0x736f6d6570736575ULL;
        # u64 v1 = 0x646f72616e646f6dULL;
        # u64 v2 = 0x6c7967656e657261ULL;
        # u64 v3 = 0x7465646279746573ULL;
       
$v = array(
           
0x736f6d65, // 0
           
0x70736575, // 1
           
0x646f7261, // 2
           
0x6e646f6d, // 3
           
0x6c796765, // 4
           
0x6e657261, // 5
           
0x74656462, // 6
           
0x79746573 // 7
       
);
       
// v0 => $v[0], $v[1]
        // v1 => $v[2], $v[3]
        // v2 => $v[4], $v[5]
        // v3 => $v[6], $v[7]

        # u64 k0 = LOAD64_LE( k );
        # u64 k1 = LOAD64_LE( k + 8 );
       
$k = array(
           
self::load_4(self::substr($key, 4, 4)),
           
self::load_4(self::substr($key, 0, 4)),
           
self::load_4(self::substr($key, 12, 4)),
           
self::load_4(self::substr($key, 8, 4))
        );
       
// k0 => $k[0], $k[1]
        // k1 => $k[2], $k[3]

        # b = ( ( u64 )inlen ) << 56;
       
$b = array(
           
$inlen << 24,
           
0
       
);
       
// See docblock for why the 0th index gets the higher bits.

        # v3 ^= k1;
       
$v[6] ^= $k[2];
       
$v[7] ^= $k[3];
       
# v2 ^= k0;
       
$v[4] ^= $k[0];
       
$v[5] ^= $k[1];
       
# v1 ^= k1;
       
$v[2] ^= $k[2];
       
$v[3] ^= $k[3];
       
# v0 ^= k0;
       
$v[0] ^= $k[0];
       
$v[1] ^= $k[1];

       
$left = $inlen;
       
# for ( ; in != end; in += 8 )
       
while ($left >= 8) {
           
# m = LOAD64_LE( in );
           
$m = array(
               
self::load_4(self::substr($in, 4, 4)),
               
self::load_4(self::substr($in, 0, 4))
            );

           
# v3 ^= m;
           
$v[6] ^= $m[0];
           
$v[7] ^= $m[1];

           
# SIPROUND;
            # SIPROUND;
           
$v = self::sipRound($v);
           
$v = self::sipRound($v);

           
# v0 ^= m;
           
$v[0] ^= $m[0];
           
$v[1] ^= $m[1];

           
$in = self::substr($in, 8);
           
$left -= 8;
        }

       
# switch( left )
        # {
        # case 7: b |= ( ( u64 )in[ 6] ) << 48;
        # case 6: b |= ( ( u64 )in[ 5] ) << 40;
        # case 5: b |= ( ( u64 )in[ 4] ) << 32;
        # case 4: b |= ( ( u64 )in[ 3] ) << 24;
        # case 3: b |= ( ( u64 )in[ 2] ) << 16;
        # case 2: b |= ( ( u64 )in[ 1] ) << 8;
        # case 1: b |= ( ( u64 )in[ 0] ); break;
        # case 0: break;
        # }
       
switch ($left) {
            case
7:
               
$b[0] |= self::chrToInt($in[6]) << 16;
            case
6:
               
$b[0] |= self::chrToInt($in[5]) << 8;
            case
5:
               
$b[0] |= self::chrToInt($in[4]);
            case
4:
               
$b[1] |= self::chrToInt($in[3]) << 24;
            case
3:
               
$b[1] |= self::chrToInt($in[2]) << 16;
            case
2:
               
$b[1] |= self::chrToInt($in[1]) << 8;
            case
1:
               
$b[1] |= self::chrToInt($in[0]);
            case
0:
                break;
        }
       
// See docblock for why the 0th index gets the higher bits.

        # v3 ^= b;
       
$v[6] ^= $b[0];
       
$v[7] ^= $b[1];

       
# SIPROUND;
        # SIPROUND;
       
$v = self::sipRound($v);
       
$v = self::sipRound($v);

       
# v0 ^= b;
       
$v[0] ^= $b[0];
       
$v[1] ^= $b[1];

       
// Flip the lower 8 bits of v2 which is ($v[4], $v[5]) in our implementation
        # v2 ^= 0xff;
       
$v[5] ^= 0xff;

       
# SIPROUND;
        # SIPROUND;
        # SIPROUND;
        # SIPROUND;
       
$v = self::sipRound($v);
       
$v = self::sipRound($v);
       
$v = self::sipRound($v);
       
$v = self::sipRound($v);

       
# b = v0 ^ v1 ^ v2 ^ v3;
        # STORE64_LE( out, b );
       
return self::store32_le($v[1] ^ $v[3] ^ $v[5] ^ $v[7]) .
           
self::store32_le($v[0] ^ $v[2] ^ $v[4] ^ $v[6]);
    }
}