Common.php in Automatic Updates 8

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vendor/paragonie/sodium_compat/src/Core/Base64/Common.php

<?php

/**
 * Class ParagonIE_Sodium_Core_Base64
 *
 *  Copyright (c) 2016 - 2018 Paragon Initiative Enterprises.
 *  Copyright (c) 2014 Steve "Sc00bz" Thomas (steve at tobtu dot com)
 *
 * We have to copy/paste the contents into the variant files because PHP 5.2
 * doesn't support late static binding, and we have no better workaround
 * available that won't break PHP 7+. Therefore, we're forced to duplicate code.
 */
abstract class ParagonIE_Sodium_Core_Base64_Common {

  /**
   * Encode into Base64
   *
   * Base64 character set "[A-Z][a-z][0-9]+/"
   *
   * @param string $src
   * @return string
   * @throws TypeError
   */
  public static function encode($src) {
    return self::doEncode($src, true);
  }

  /**
   * Encode into Base64, no = padding
   *
   * Base64 character set "[A-Z][a-z][0-9]+/"
   *
   * @param string $src
   * @return string
   * @throws TypeError
   */
  public static function encodeUnpadded($src) {
    return self::doEncode($src, false);
  }

  /**
   * @param string $src
   * @param bool $pad   Include = padding?
   * @return string
   * @throws TypeError
   */
  protected static function doEncode($src, $pad = true) {
    $dest = '';
    $srcLen = ParagonIE_Sodium_Core_Util::strlen($src);

    // Main loop (no padding):
    for ($i = 0; $i + 3 <= $srcLen; $i += 3) {

      /** @var array<int, int> $chunk */
      $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, 3));
      $b0 = $chunk[1];
      $b1 = $chunk[2];
      $b2 = $chunk[3];
      $dest .= self::encode6Bits($b0 >> 2) . self::encode6Bits(($b0 << 4 | $b1 >> 4) & 63) . self::encode6Bits(($b1 << 2 | $b2 >> 6) & 63) . self::encode6Bits($b2 & 63);
    }

    // The last chunk, which may have padding:
    if ($i < $srcLen) {

      /** @var array<int, int> $chunk */
      $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, $srcLen - $i));
      $b0 = $chunk[1];
      if ($i + 1 < $srcLen) {
        $b1 = $chunk[2];
        $dest .= self::encode6Bits($b0 >> 2) . self::encode6Bits(($b0 << 4 | $b1 >> 4) & 63) . self::encode6Bits($b1 << 2 & 63);
        if ($pad) {
          $dest .= '=';
        }
      }
      else {
        $dest .= self::encode6Bits($b0 >> 2) . self::encode6Bits($b0 << 4 & 63);
        if ($pad) {
          $dest .= '==';
        }
      }
    }
    return $dest;
  }

  /**
   * decode from base64 into binary
   *
   * Base64 character set "./[A-Z][a-z][0-9]"
   *
   * @param string $src
   * @param bool $strictPadding
   * @return string
   * @throws RangeException
   * @throws TypeError
   * @psalm-suppress RedundantCondition
   */
  public static function decode($src, $strictPadding = false) {

    // Remove padding
    $srcLen = ParagonIE_Sodium_Core_Util::strlen($src);
    if ($srcLen === 0) {
      return '';
    }
    if ($strictPadding) {
      if (($srcLen & 3) === 0) {
        if ($src[$srcLen - 1] === '=') {
          $srcLen--;
          if ($src[$srcLen - 1] === '=') {
            $srcLen--;
          }
        }
      }
      if (($srcLen & 3) === 1) {
        throw new RangeException('Incorrect padding');
      }
      if ($src[$srcLen - 1] === '=') {
        throw new RangeException('Incorrect padding');
      }
    }
    else {
      $src = rtrim($src, '=');
      $srcLen = ParagonIE_Sodium_Core_Util::strlen($src);
    }
    $err = 0;
    $dest = '';

    // Main loop (no padding):
    for ($i = 0; $i + 4 <= $srcLen; $i += 4) {

      /** @var array<int, int> $chunk */
      $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, 4));
      $c0 = self::decode6Bits($chunk[1]);
      $c1 = self::decode6Bits($chunk[2]);
      $c2 = self::decode6Bits($chunk[3]);
      $c3 = self::decode6Bits($chunk[4]);
      $dest .= pack('CCC', ($c0 << 2 | $c1 >> 4) & 0xff, ($c1 << 4 | $c2 >> 2) & 0xff, ($c2 << 6 | $c3) & 0xff);
      $err |= ($c0 | $c1 | $c2 | $c3) >> 8;
    }

    // The last chunk, which may have padding:
    if ($i < $srcLen) {

      /** @var array<int, int> $chunk */
      $chunk = unpack('C*', ParagonIE_Sodium_Core_Util::substr($src, $i, $srcLen - $i));
      $c0 = self::decode6Bits($chunk[1]);
      if ($i + 2 < $srcLen) {
        $c1 = self::decode6Bits($chunk[2]);
        $c2 = self::decode6Bits($chunk[3]);
        $dest .= pack('CC', ($c0 << 2 | $c1 >> 4) & 0xff, ($c1 << 4 | $c2 >> 2) & 0xff);
        $err |= ($c0 | $c1 | $c2) >> 8;
      }
      elseif ($i + 1 < $srcLen) {
        $c1 = self::decode6Bits($chunk[2]);
        $dest .= pack('C', ($c0 << 2 | $c1 >> 4) & 0xff);
        $err |= ($c0 | $c1) >> 8;
      }
      elseif ($i < $srcLen && $strictPadding) {
        $err |= 1;
      }
    }

    /** @var bool $check */
    $check = $err === 0;
    if (!$check) {
      throw new RangeException('Base64::decode() only expects characters in the correct base64 alphabet');
    }
    return $dest;
  }

  /**
   * Uses bitwise operators instead of table-lookups to turn 6-bit integers
   * into 8-bit integers.
   *
   * Base64 character set:
   * [A-Z]      [a-z]      [0-9]      +     /
   * 0x41-0x5a, 0x61-0x7a, 0x30-0x39, 0x2b, 0x2f
   *
   * @param int $src
   * @return int
   */
  protected static abstract function decode6Bits($src);

  /**
   * Uses bitwise operators instead of table-lookups to turn 8-bit integers
   * into 6-bit integers.
   *
   * @param int $src
   * @return string
   */
  protected static abstract function encode6Bits($src);

}

Classes

Name	Description
ParagonIE_Sodium_Core_Base64_Common	Class ParagonIE_Sodium_Core_Base64