CI_Encrypt

CI_Encrypt

CodeIgniter Encryption Class

Provides two-way keyed encoding using Mcrypt

• Class name: CI_Encrypt
• Namespace:

Properties

$encryption_key

public string $encryption_key = ''

Reference to the user's encryption key

• Visibility: public

$_hash_type

protected string $_hash_type = 'sha1'

Type of hash operation

• Visibility: protected

$_mcrypt_exists

protected boolean $_mcrypt_exists = FALSE

Flag for the existence of mcrypt

• Visibility: protected

$_mcrypt_cipher

protected string $_mcrypt_cipher

Current cipher to be used with mcrypt

• Visibility: protected

$_mcrypt_mode

protected integer $_mcrypt_mode

Method for encrypting/decrypting data

• Visibility: protected

Methods

__construct

void CI_Encrypt::__construct()

Initialize Encryption class

• Visibility: public

get_key

string CI_Encrypt::get_key($key)

Fetch the encryption key

Returns it as MD5 in order to have an exact-length 128 bit key. Mcrypt is sensitive to keys that are not the correct length

• Visibility: public

Arguments

• $key mixed

set_key

\CI_Encrypt CI_Encrypt::set_key($key)

Set the encryption key

• Visibility: public

Arguments

• $key mixed

encode

string CI_Encrypt::encode($string, $key)

Encode

Encodes the message string using bitwise XOR encoding. The key is combined with a random hash, and then it too gets converted using XOR. The whole thing is then run through mcrypt using the randomized key. The end result is a double-encrypted message string that is randomized with each call to this function, even if the supplied message and key are the same.

• Visibility: public

Arguments

• $string mixed
• $key mixed

decode

string CI_Encrypt::decode($string, $key)

Decode

Reverses the above process

• Visibility: public

Arguments

• $string mixed
• $key mixed

encode_from_legacy

string CI_Encrypt::encode_from_legacy($string, $legacy_mode, $key)

Encode from Legacy

Takes an encoded string from the original Encryption class algorithms and returns a newly encoded string using the improved method added in 2.0.0 This allows for backwards compatibility and a method to transition to the new encryption algorithms.

For more details, see http://codeigniter.com/user_guide/installation/upgrade_200.html#encryption

• Visibility: public

Arguments

• $string mixed
• $legacy_mode mixed
• $key mixed

_xor_decode

string CI_Encrypt::_xor_decode($string, $key)

XOR Decode

Takes an encoded string and key as input and generates the plain-text original message

• Visibility: protected

Arguments

• $string mixed
• $key mixed

_xor_merge

string CI_Encrypt::_xor_merge($string, $key)

XOR key + string Combiner

Takes a string and key as input and computes the difference using XOR

• Visibility: protected

Arguments

• $string mixed
• $key mixed

mcrypt_encode

string CI_Encrypt::mcrypt_encode($data, $key)

Encrypt using Mcrypt

• Visibility: public

Arguments

• $data mixed
• $key mixed

mcrypt_decode

string CI_Encrypt::mcrypt_decode($data, $key)

Decrypt using Mcrypt

• Visibility: public

Arguments

• $data mixed
• $key mixed

_add_cipher_noise

string CI_Encrypt::_add_cipher_noise($data, $key)

Adds permuted noise to the IV + encrypted data to protect against Man-in-the-middle attacks on CBC mode ciphers http://www.ciphersbyritter.com/GLOSSARY.HTM#IV

• Visibility: protected

Arguments

• $data mixed
• $key mixed

_remove_cipher_noise

string CI_Encrypt::_remove_cipher_noise(string $data, string $key)

Removes permuted noise from the IV + encrypted data, reversing _add_cipher_noise()

Function description

• Visibility: protected

Arguments

• $data string
• $key string

set_cipher

\CI_Encrypt CI_Encrypt::set_cipher($cipher)

Set the Mcrypt Cipher

• Visibility: public

Arguments

• $cipher mixed

set_mode

\CI_Encrypt CI_Encrypt::set_mode($mode)

Set the Mcrypt Mode

• Visibility: public

Arguments

• $mode mixed

_get_cipher

integer CI_Encrypt::_get_cipher()

Get Mcrypt cipher Value

• Visibility: protected

_get_mode

integer CI_Encrypt::_get_mode()

Get Mcrypt Mode Value

• Visibility: protected

set_hash

void CI_Encrypt::set_hash($type)

Set the Hash type

• Visibility: public

Arguments

• $type mixed

hash

string CI_Encrypt::hash($str)

Hash encode a string

• Visibility: public

Arguments

• $str mixed