Ctx.php in Automatic Updates 8

File

vendor/paragonie/sodium_compat/src/Core/ChaCha20/Ctx.php

<?php

if (class_exists('ParagonIE_Sodium_Core_ChaCha20_Ctx', false)) {
  return;
}

/**
 * Class ParagonIE_Sodium_Core_ChaCha20_Ctx
 */
class ParagonIE_Sodium_Core_ChaCha20_Ctx extends ParagonIE_Sodium_Core_Util implements ArrayAccess {

  /**
   * @var SplFixedArray internally, <int, int>
   */
  protected $container;

  /**
   * ParagonIE_Sodium_Core_ChaCha20_Ctx constructor.
   *
   * @internal You should not use this directly from another application
   *
   * @param string $key     ChaCha20 key.
   * @param string $iv      Initialization Vector (a.k.a. nonce).
   * @param string $counter The initial counter value.
   *                        Defaults to 8 0x00 bytes.
   * @throws InvalidArgumentException
   * @throws TypeError
   */
  public function __construct($key = '', $iv = '', $counter = '') {
    if (self::strlen($key) !== 32) {
      throw new InvalidArgumentException('ChaCha20 expects a 256-bit key.');
    }
    if (self::strlen($iv) !== 8) {
      throw new InvalidArgumentException('ChaCha20 expects a 64-bit nonce.');
    }
    $this->container = new SplFixedArray(16);

    /* "expand 32-byte k" as per ChaCha20 spec */
    $this->container[0] = 0x61707865;
    $this->container[1] = 0x3320646e;
    $this->container[2] = 0x79622d32;
    $this->container[3] = 0x6b206574;
    $this->container[4] = self::load_4(self::substr($key, 0, 4));
    $this->container[5] = self::load_4(self::substr($key, 4, 4));
    $this->container[6] = self::load_4(self::substr($key, 8, 4));
    $this->container[7] = self::load_4(self::substr($key, 12, 4));
    $this->container[8] = self::load_4(self::substr($key, 16, 4));
    $this->container[9] = self::load_4(self::substr($key, 20, 4));
    $this->container[10] = self::load_4(self::substr($key, 24, 4));
    $this->container[11] = self::load_4(self::substr($key, 28, 4));
    if (empty($counter)) {
      $this->container[12] = 0;
      $this->container[13] = 0;
    }
    else {
      $this->container[12] = self::load_4(self::substr($counter, 0, 4));
      $this->container[13] = self::load_4(self::substr($counter, 4, 4));
    }
    $this->container[14] = self::load_4(self::substr($iv, 0, 4));
    $this->container[15] = self::load_4(self::substr($iv, 4, 4));
  }

  /**
   * @internal You should not use this directly from another application
   *
   * @param int $offset
   * @param int $value
   * @return void
   * @psalm-suppress MixedArrayOffset
   */
  public function offsetSet($offset, $value) {
    if (!is_int($offset)) {
      throw new InvalidArgumentException('Expected an integer');
    }
    if (!is_int($value)) {
      throw new InvalidArgumentException('Expected an integer');
    }
    $this->container[$offset] = $value;
  }

  /**
   * @internal You should not use this directly from another application
   *
   * @param int $offset
   * @return bool
   */
  public function offsetExists($offset) {
    return isset($this->container[$offset]);
  }

  /**
   * @internal You should not use this directly from another application
   *
   * @param int $offset
   * @return void
   * @psalm-suppress MixedArrayOffset
   */
  public function offsetUnset($offset) {
    unset($this->container[$offset]);
  }

  /**
   * @internal You should not use this directly from another application
   *
   * @param int $offset
   * @return mixed|null
   * @psalm-suppress MixedArrayOffset
   */
  public function offsetGet($offset) {
    return isset($this->container[$offset]) ? $this->container[$offset] : null;
  }

}

Classes

Name	Description
ParagonIE_Sodium_Core_ChaCha20_Ctx	Class ParagonIE_Sodium_Core_ChaCha20_Ctx