Implementation method of DES encryption and decryption in PHP and. NET _php instance

php5.x version, to add PHP extension php_mcrypt.

PHP Version:

Copy Code code as follows:

Class Std3des
{
Private $key = "";
Private $iv = "";

/**
* Constructs, passing two key and IV which have been base64_encode
*
* @param string $key
* @param string $iv
*/
function __construct ($key, $iv)
{
if (Empty ($key) | | empty ($IV)) {
Echo ' key ' and ' IV ' not valid ';
Exit ();
}
$this->key = $key;
$this->iv = $iv;
}

/**
* Encryption
* @param <type> $value
* @return <type>
*/
Public function Encrypt ($value)
{
$TD = Mcrypt_module_open (Mcrypt_3des, ', MCRYPT_MODE_CBC, ');
$iv = Base64_decode ($this->iv);
$value = $this-&GT;PADDINGPKCS7 ($value);
$key = Base64_decode ($this->key);
Mcrypt_generic_init ($TD, $key, $IV);
$ret = Base64_encode (Mcrypt_generic ($TD, $value));
Mcrypt_generic_deinit ($TD);
Mcrypt_module_close ($TD);
return $ret;
}

/**
* Decryption
* @param <type> $value
* @return <type>
*/
Public function decrypt ($value)
{
$TD = Mcrypt_module_open (Mcrypt_3des, ', MCRYPT_MODE_CBC, ');
$iv = Base64_decode ($this->iv);
$key = Base64_decode ($this->key);
Mcrypt_generic_init ($TD, $key, $IV);
$ret = Trim (Mdecrypt_generic ($TD, Base64_decode ($value));
$ret = $this-&GT;UNPADDINGPKCS7 ($ret);
Mcrypt_generic_deinit ($TD);
Mcrypt_module_close ($TD);
return $ret;
}

Private Function PaddingPKCS7 ($data)
{
$block _size = mcrypt_get_block_size (' TripleDES ', ' CBC ');
$padding _char = $block _size-(strlen ($data)% $block _size);
$data. = Str_repeat (Chr ($padding _char), $padding _char);
return $data;
}

Private Function UnPaddingPKCS7 ($text)
{
$pad = Ord ($text {strlen ($text)-1});
if ($pad > strlen ($text)) {
return false;
}
if (strspn ($text, Chr ($pad), strlen ($text)-$pad)!= $pad) {
return false;
}
Return substr ($text, 0,-1 * $pad);
}
}


Use
Include (' STD3Des.class.php ');
$key = ' abcdefgh ';
$iv = ' abcdefgh ';
$msg = ' Test string ';
$des =new std3des (Base64_encode ($key), Base64_encode ($IV));
$rs 1= $des->encrypt ($msg);
echo $rs 1. ' <br/> ';
$rs 2= $des->decrypt ($rs 1);
echo $rs 2;

. NET version

Copy Code code as follows:

Sealed public class Cryptohelper
{
<summary>
Encrypts the specified input.
</summary>
<param name= "Input" >the input.</param>
<param name= "Key" >key</param>
<param name= "IV" >iv</param>
<returns></returns>
public static string Encryptdes (string input, byte[] key, byte[] IV)
{
if (input = = NULL | | input. Length = = 0)
return String.Empty;

DESCryptoServiceProvider des = new DESCryptoServiceProvider ();
MemoryStream ms = NULL;
CryptoStream encstream = null;
StreamWriter sw = null;
string result = String.Empty;

Try
{
ms = new MemoryStream ();

Create a CryptoStream using the memory stream and the
CSP DES key.
Des. Mode = CIPHERMODE.CBC;
Des. Padding = PADDINGMODE.PKCS7;
Encstream = new CryptoStream (MS, Des. CreateEncryptor (Key, iv), CryptoStreamMode.Write);

Create a StreamWriter to write a string
to the stream.
SW = new StreamWriter (Encstream);

Write the plaintext to the stream.
Sw. Write (input);

Sw. Flush ();
Encstream.flushfinalblock ();
Ms. Flush ();


result = Convert.tobase64string (Ms. GetBuffer (), 0, Convert.ToInt32 (Ms. Length, CultureInfo.InvariantCulture));
}
Finally
{
Close objects
if (SW!= null)
Sw. Close ();
if (Encstream!= null)
Encstream.close ();
if (MS!= null)
Ms. Close ();
}

Return the encrypted string
return result;
}
<summary>
Decrypts the specified input.
</summary>
<param name= "Input" >the input.</param>
<param name= "Key" >key</param>
<param name= "IV" >iv</param>
<returns></returns>
public static string Decryptdes (string input, byte[] key, byte[] IV)
{
byte[] buffer;
try {buffer = convert.frombase64string (input);}
catch (system.argumentnullexception) {return string.empty;}
Length is zero, or isn't an even multiple of four (plus a few other cases)
catch (system.formatexception) {return string.empty;}

DESCryptoServiceProvider des = new DESCryptoServiceProvider ();
MemoryStream ms = NULL;
CryptoStream encstream = null;
StreamReader sr = null;
string result = String.Empty;

Try
{
ms = new MemoryStream (buffer);

Create a CryptoStream using the memory stream and the
CSP DES key.
Encstream = new CryptoStream (MS, Des. CreateDecryptor (Key, iv), CryptoStreamMode.Read);

Create a StreamReader for reading the stream.
sr = new StreamReader (encstream);

Read the stream as a string.
result = Sr. ReadToEnd ();
}
Finally
{
Close objects
if (SR!= null)
Sr. Close ();
if (Encstream!= null)
Encstream.close ();
if (MS!= null)
Ms. Close ();
}

return result;
}
}


Call

string key = "ABCDEFGH";
String IV = "ABCDEFGH";
String msg= "test string";
String rs1 = Cryptohelper.encryptdes (msg, System.Text.Encoding.ASCII.GetBytes (key), System.Text.Encoding.ASCII.GetBytes (iv));
string rs2 = Cryptohelper.decryptdes (Rs1, System.Text.Encoding.ASCII.GetBytes (key), System.Text.Encoding.ASCII.GetBytes (iv));