The AES(Advanced Encryption Standard) is a widely-used crypto specification made by the NIST. There are ECB and CBC methods in the AES.
The following is an explanation to encrypt/decrypt data with the ECB.
This command is for initializing PHPoC's AES crypto engine. So this command should be executed prior to the encryption/decryption. This command returns a context which is used for encryption and decryption.
| Parameter | Description |
|---|---|
| enc/dec | enc - encryption dec - decryption |
| $ecb_key | the 128/192/256 bits key to be used encryption and decryption |
The AES encryption or decryption is performed with this command according to initialization command. It returns the data which was encrypted or decrypted.
| Parameter | Description |
|---|---|
| $aes | the context when the crypto engine was initialized |
| $text | plain text to be encrypted or cipher text to be decrypted |
The following is an explanation to encrypt/decrypt data with the CBC.
This command is for initializing PHPoC's AES crypto engine. So this command should be executed prior to the encryption/decryption. This command returns a context which is used for encryption and decryption.
| Parameter | Description |
|---|---|
| $enc/dec | enc - encryption / dec - decryption |
| $cbc_key | the 128/192/256 bits key to be used in encryption and decryption |
| $iv | 128 bits initialization vector |
The AES encryption or decryption is performed with this command according to initialization command. It returns the data which was encrypted or decrypted.
| Parameter | Description |
|---|---|
| $aes | the context when the crypto engine was initialized |
| $text | plain text to be encrypted or cipher text to be decrypted |
The following is an example of the CBC-based AES encryption and decryption.
// encryption
$aes = system("aes init cbc enc %1 %2", $cbc_key, $cbc_iv);
$out = system("aes crypt %1 %2", $aes, $cbc_pt16);
// decryption
$aes = system("aes init cbc dec %1 %2", $cbc_key, $cbc_iv);
$out = system("aes crypt %1 %2", $aes, $cbc_ct16);