<?php
namespace Aws\Crypto\Cipher;
interface CipherMethod
{
/**
* Returns an identifier recognizable by `openssl_*` functions, such as
* `aes-256-cbc` or `aes-128-ctr`.
*
* @return string
*/
public function getOpenSslName();
/**
* Returns an AES recognizable name, such as 'AES/GCM/NoPadding'.
*
* @return string
*/
public function getAesName();
/**
* Returns the IV that should be used to initialize the next block in
* encrypt or decrypt.
*
* @return string
*/
public function getCurrentIv();
/**
* Indicates whether the cipher method used with this IV requires padding
* the final block to make sure the plaintext is evenly divisible by the
* block size.
*
* @return boolean
*/
public function requiresPadding();
/**
* Adjust the return of this::getCurrentIv to reflect a seek performed on
* the encryption stream using this IV object.
*
* @param int $offset
* @param int $whence
*
* @throws LogicException Thrown if the requested seek is not supported by
* this IV implementation. For example, a CBC IV
* only supports a full rewind ($offset === 0 &&
* $whence === SEEK_SET)
*/
public function seek($offset, $whence = SEEK_SET);
/**
* Take account of the last cipher text block to adjust the return of
* this::getCurrentIv
*
* @param string $cipherTextBlock
*/
public function update($cipherTextBlock);
}