AES Encryption-decryption algorithm in C # and Java

One, C # version AES encryption and decryption algorithm

    Public classAescode { Public stringKey {Get;Set; }  Public stringEncrypt (stringval) {            if(string. IsNullOrEmpty (val))return NULL;#ifCspusing(Aescryptoserviceprovider des =NewAescryptoserviceprovider ())#else            using(Aesmanaged des =Newaesmanaged ())#endif            {                byte[] Inputbytearray =Encoding.UTF8.GetBytes (Val); byte[] _key; byte[] _iv; Generalkeyiv ( This. Key, out_key, out_iv); Des. Key=_key; Des.iv=_iv; using(MemoryStream ms =NewMemoryStream ()) {                    using(CryptoStream cs =NewCryptoStream (MS, Des. CreateEncryptor (), cryptostreammode.write)) {cs. Write (Inputbytearray,0, inputbytearray.length); Cs.                        FlushFinalBlock (); byte[] bytes = (byte[]) Ms.                        ToArray (); returnconvert.tobase64string (bytes); }                }            }        }         Public stringDecrypt (stringval) {            if(string. IsNullOrEmpty (val))return NULL;#ifCspusing(Aescryptoserviceprovider des =NewAescryptoserviceprovider ())#else            using(Aesmanaged des =Newaesmanaged ())#endif            {                byte[] Inputbytearray =Convert.frombase64string (Val); byte[] _key; byte[] _iv; Generalkeyiv ( This. Key, out_key, out_iv); Des. Key=_key; Des.iv=_iv; using(MemoryStream ms =NewMemoryStream ()) {                    using(CryptoStream cs =NewCryptoStream (MS, Des. CreateDecryptor (), cryptostreammode.write)) {cs. Write (Inputbytearray,0, inputbytearray.length); Cs.                        FlushFinalBlock (); returnEncoding.UTF8.GetString (Ms.                    ToArray ()); }                }            }        }         Public voidGeneralkeyiv (stringKEYSTR, out byte[] Key, out byte[] iv) {byte[] bytes =Encoding.UTF8.GetBytes (KEYSTR); Key=sha256managed.create ().            ComputeHash (bytes); IV=MD5. Create ().        ComputeHash (bytes); }}

Second, Java version of the algorithm

Importjava.security.MessageDigest;ImportJavax.crypto.Cipher;ImportJavax.crypto.spec.IvParameterSpec;ImportJavax.crypto.spec.SecretKeySpec;Importorg.apache.commons.codec.binary.Base64; Public classAescode {/*** provide key and vector for encryption * *@paramSSRC *@paramKey *@paramIV *@return     * @throwsException*/     Public StaticString Encrypt (String sSrc,byte[] Key,byte[] IV)throwsException {secretkeyspec Skeyspec=NewSecretkeyspec (Key, "AES"); Cipher Cipher= Cipher.getinstance ("aes/cbc/pkcs5padding");//"algorithm/Mode/complement Method"Ivparameterspec _iv =NewIvparameterspec (iv);//using CBC mode, a vector IV is required to increase the strength of the encryption algorithmCipher.init (Cipher.encrypt_mode, Skeyspec, _iv); byte[] encrypted = Cipher.dofinal (Ssrc.getbytes ("Utf-8")); returnBase64.encodebase64string (encrypted);    }    /*** provide key and vector for decryption * *@paramSSRC *@paramKey *@paramIV *@return     * @throwsException*/     Public StaticString Decrypt (String sSrc,byte[] Key,byte[] IV)throwsException {secretkeyspec Skeyspec=NewSecretkeyspec (Key, "AES"); Cipher Cipher= Cipher.getinstance ("aes/cbc/pkcs5padding"); Ivparameterspec _iv=NewIvparameterspec (iv);        Cipher.init (Cipher.decrypt_mode, Skeyspec, _iv); byte[] encrypted = Base64.decodebase64 (SSRC);byte[] Original =cipher.dofinal (encrypted); return NewString (Original, "Utf-8"); }    /*** Use key for encryption * *@paramSSRC *@paramKeystr *@return     * @throwsException*/     Public StaticString Encrypt (String sSrc, String keystr)throwsException {byte[] key =Generalkey (KEYSTR); byte[] IV =Generaliv (KEYSTR); Secretkeyspec Skeyspec=NewSecretkeyspec (Key, "AES"); Cipher Cipher= Cipher.getinstance ("aes/cbc/pkcs5padding");//"algorithm/Mode/complement Method"Ivparameterspec _iv =NewIvparameterspec (iv);Cipher.init (Cipher.encrypt_mode, Skeyspec, _iv); byte[] encrypted = Cipher.dofinal (Ssrc.getbytes ("Utf-8")); returnBase64.encodebase64string (encrypted);    }    /*** Use key to decrypt * *@paramSSRC *@paramKeystr *@return     * @throwsException*/     Public StaticString Decrypt (String sSrc, String keystr)throwsException {byte[] key =Generalkey (KEYSTR); byte[] IV =Generaliv (KEYSTR); Secretkeyspec Skeyspec=NewSecretkeyspec (Key, "AES"); Cipher Cipher= Cipher.getinstance ("aes/cbc/pkcs5padding"); Ivparameterspec _iv=NewIvparameterspec (iv);        Cipher.init (Cipher.decrypt_mode, Skeyspec, _iv); byte[] encrypted = Base64.decodebase64 (SSRC);//first decode with base64        byte[] Original =cipher.dofinal (encrypted); return NewString (Original, "Utf-8"); }    /*** Build Key byte code * *@paramKeystr *@return     * @throwsException*/    Private Static byte[] Generalkey (String keystr)throwsException {byte[] bytes = Keystr.getbytes ("Utf-8"); MessageDigest MD= Messagedigest.getinstance ("SHA-256");        Md.update (bytes); returnmd.digest (); }    /*** Build and decrypt vector byte code * *@paramKeystr *@return     * @throwsException*/    Private Static byte[] Generaliv (String keystr)throwsException {byte[] bytes = Keystr.getbytes ("Utf-8"); MessageDigest MD= Messagedigest.getinstance ("MD5");        Md.update (bytes); returnmd.digest (); }}

Java Edition requires Commons-codec-1.10.jar,local_policy.jar,us_export_policy.jar

AES Encryption-decryption algorithm in C # and Java