OpenSSL
class OpenSSL extends AbstractAES implements AesInterface
OpenSSL encryption class
Properties
| protected int | $openSSLOptions | The OpenSSL options for encryption / decryption |
|
| protected string | $method | The encryption method to use |
Methods
Returns null bytes to append to the string so that it's zero padded to the specified block size
Constructor for this class
Sets the AES encryption mode.
Encrypts a string. Returns the raw binary ciphertext.
Decrypts a string. Returns the raw binary plaintext.
Is this adapter supported?
Returns the encryption block size in bytes
Details
protected string
getZeroPadding(string $string, int $blockSize)
Returns null bytes to append to the string so that it's zero padded to the specified block size
mixed
setEncryptionMode(string $mode = 'cbc', int $strength = 128)
Sets the AES encryption mode.
WARNING: The strength is deprecated as it has a different effect in MCrypt and OpenSSL. MCrypt was abandoned in 2003 before the Rijndael-128 algorithm was officially the Advanced Encryption Standard (AES). MCrypt also offered Rijndael-192 and Rijndael-256 algorithms with different block sizes. These are NOT used in AES. OpenSSL, however, implements AES correctly. It always uses a 128-bit (16 byte) block. The 192 and 256 bit strengths refer to the key size, not the block size. Therefore using different strengths in MCrypt and OpenSSL will result in different and incompatible ciphertexts.
TL;DR: Always use $strength = 128!
string
encrypt(string $plainText, string $key, null|string $iv = null)
Encrypts a string. Returns the raw binary ciphertext.
WARNING: The plaintext is zero-padded to the algorithm's block size. You are advised to store the size of the plaintext and trim the string to that length upon decryption.
string
decrypt(string $cipherText, string $key)
Decrypts a string. Returns the raw binary plaintext.
$ciphertext MUST start with the IV followed by the ciphertext, even for EBC data (the first block of data is dropped in EBC mode since there is no concept of IV in EBC).
WARNING: The returned plaintext is zero-padded to the algorithm's block size during encryption. You are advised to trim the string to the original plaintext's length upon decryption. While rtrim($decrypted, "\0") sounds appealing it's NOT the correct approach for binary data (zero bytes may actually be part of your plaintext, not just padding!).