openlss/lib-crypt

Shorthand library for using AES encryption provided by PHP-Mcrypt

0.0.10 2013-04-17 21:51 UTC

Requires

• php: >=5.3.2
• openlss/lib-config: ~0.0.1

Requires (Dev)

• openlss/core-boot: ~0.0.1
• openlss/lib-config: ~0.0.1

LGPL-3.0+

• Bryan Tong
• Tony Butler

• encryption
• aes
• decryption
• mcrypt

README

Shorthand library for using AES encryption provided by PHP-Mcrypt

Usage

use \LSS\Crypt;

//create keys
$iv_key = Crypt::IVCreate();
$crypt_key = Crypt::keyCreate();

$crypt = Crypt::_get($crypt_key,$iv_key);
$crypted_str = $crypt->encrypt('my string'); //returns base64 encoded crypted string
$var = $crypt->decrypt($crypted_str); //returns 'my string'

Padding

By default MCrypt will NULL-PAD strings to get the proper encryption. However this creates problems when expecting exact payload encryption (such as binary)

Crypt deals with this by storing the size of the payload as the first 4 bytes in the returned string Crypt then extracts this size and trims the payload to the original size upon decrypt

The downside to this is that it cant be decrypted by the regular MCrypt functions without first stripping the initial 4 bytes. It would be recommended to trim the payload if possible

Reference

(string) Crypt::IVCreate()

Returns a proper initialization vector for the encryption type

(string) Crypt::keyCreate()

Returns a proper secret key for the encryption type

(object) Crypt::_get($key,$iv)

Shorthand for the construct that returns the new object

(object) Crypt::setKey($key)

Change the key at runtime Returns $this so its chainable

(object) Crypt::setIV($iv)

Change the IV at runtime Returns $this so its chainable

(object) Crypt::verify()

Verifies the key and IV Will throw exceptions on errors Returns $this so its chainable

(string) Crypt::encrypt($plain_string,$base64_encode=true)

• $plain_string String to be encrypted
• $base64_encode TRUE to base64_encode the encrypted string Returns the encrypted and optionally base64_encoded string

(string) Crypt::decrypt($enc_string,$base64_decode=true)

• $enc_string The encrypted string to be decrypted
• $base64_decode If the $enc_string is base64_encoded set to TRUE Returns the EXACT original string