About DES encryption and decryption implementations (PHP net two versions)

/** DES encryption and decryption */ Class Std3des { Private $key = ""; Private $iv = ""; /** * Construct, pass two key and IV that have been base64_encode * * @param string $key * @param string $iv */ function __construct ($key, $iv) { if (Empty ($key) | | empty ($IV)) { Echo ' key and IV is not valid '; Exit (); } $this->key = $key; $this->iv = $iv; } /** * Encryption * @param $value * @return */ Public function Encrypt ($value) { $TD = Mcrypt_module_open (Mcrypt_3des, ', MCRYPT_MODE_CBC, '); $iv = Base64_decode ($this->iv); $value = $this->PADDINGPKCS7 ($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 $value * @return */ Public function decrypt ($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 = $this->UNPADDINGPKCS7 ($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. ' '; $rs 2= $des->decrypt ($rs 1); echo $rs 2; Copy Code 2. NET version DES encryption and decryption Sealed public class Cryptohelper { /// Encrypts the specified input. /// the input. Key IV /// 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; } /// Decrypts the specified input. /// the input. Key IV /// 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 the 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)); Copy Code After reading the above two pieces of code, do not know you have harvest? Personal prefer the PHP version of the DES Encryption and decryption method, concise and clear. Scripting Academy (bbs.it-home.org), focus on you.

