因为项目的需求,最近几天一直在看关于加密的问题,将项目中使用到的DES加密整理一下,它可以使用适用于NET,Android,iOS三个平台.

DES加密,DES有两种,一种是DES,对每组分组进行一次加密,另一种是DES的升级版3DES,就是对每组分组进行3此加密,前者最大可使用8位的密匙,后者最大可使用24为密匙。

看代码:

.NET


//////
/// 密匙
//////
public static string sKey = "12345678";

///
/// 解密
///
/// 要解密的以Base64
/// 密钥,且必须为8位
/// 已解密的字符串
public static string DesDecrypt(string pToDecrypt)
{
     //转义特殊字符
     pToDecrypt = pToDecrypt.Replace("-", "+");
     pToDecrypt = pToDecrypt.Replace("_", "/");
     pToDecrypt = pToDecrypt.Replace("~", "=");
     byte[] inputByteArray = Convert.FromBase64String(pToDecrypt);
     using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())
     {
         des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
         des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
         System.IO.MemoryStream ms = new System.IO.MemoryStream();
         using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))
         {
             cs.Write(inputByteArray, 0, inputByteArray.Length);
             cs.FlushFinalBlock();
             cs.Close();
         }
         string str = Encoding.UTF8.GetString(ms.ToArray());
         ms.Close();
         return str;
     }
}




/// 对字符串进行DES加密
///
/// 待加密的字符串
/// 加密后的BASE64编码的字符串
public string Encrypt(string sourceString)
{
   byte[] btKey = Encoding.UTF8.GetBytes(sKey);
   byte[] btIV = Encoding.UTF8.GetBytes(sKey);
   DESCryptoServiceProvider des = new DESCryptoServiceProvider();
   using (MemoryStream ms = new MemoryStream())
    {
        byte[] inData = Encoding.UTF8.GetBytes(sourceString);
        try
       {
           using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(btKey, btIV), CryptoStreamMode.Write))
           {
               cs.Write(inData, 0, inData.Length);
               cs.FlushFinalBlock();
            }
            return Convert.ToBase64String(ms.ToArray());
        }
       catch
        {
            throw;
        }
    }
}

Android


// 加密
public static String DecryptDoNet(String message, String key)

       throws Exception {

    byte[] bytesrc = Base64.decode(message.getBytes(), Base64.DEFAULT);

    Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

    DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));

    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

   SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

    IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));

    cipher.init(Cipher.DECRYPT_MODE, secretKey, iv);

    byte[] retByte = cipher.doFinal(bytesrc);

    return new String(retByte);

}



// 解密
public static String EncryptAsDoNet(String message, String key)  throws Exception {

   Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

    DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));

    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

    SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

    IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));

    cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

    byte[] encryptbyte = cipher.doFinal(message.getBytes());

    return new String(Base64.encode(encryptbyte, Base64.DEFAULT));

}

iOS



/**
 *  DES加密解密(封装参数为NSString)
 *
 *  @param content 加解密内容
 *  @param type    加/解密
 *  @param aKey    密匙
 *
 *  @return 加/解密后的内容
 */
+(NSString*)encryptWithContent:(NSString*)content type:(CCOperation)type key:(NSString*)aKey
{
    const char * contentChar =[content UTF8String];
    char * keyChar =(char*)[aKey UTF8String];
    const char *miChar;
    miChar = encryptWithKeyAndType(contentChar, type, keyChar);
    return [NSString stringWithCString:miChar encoding:NSUTF8StringEncoding];
}


/**
 *  DES加密解密
 *
 *  @param text             需要加/解密的内容
 *  @param encryptOperation 加/解密
 *  @param key              密匙
 *
 *  @return 加/解密后的内容
 */
static const char* encryptWithKeyAndType(const char *text,CCOperation encryptOperation,char *key)
{
    NSString *textString=[[NSString alloc]initWithCString:text encoding:NSUTF8StringEncoding];
    const void *dataIn;//
    size_t dataInLength;
    if (encryptOperation == kCCDecrypt)//传递过来的是decrypt 解码
    {
        //解码 base64   //   !!!!!!!!!!!!!!!!!-------->【解密进行了Base64字符串处理】,加密时使用,如要使用,去除Base64即可
        NSData *decryptData = [GTMBase64 decodeData:[textString dataUsingEncoding:NSUTF8StringEncoding]];//转成utf-8并decode
        dataInLength = [decryptData length];
        dataIn = [decryptData bytes];
     }
    else //encrypt
     {
         NSData* encryptData = [textString dataUsingEncoding:NSUTF8StringEncoding];
         dataInLength = [encryptData length];
         dataIn = (const void *)[encryptData bytes];
     }

     CCCryptorStatus ccStatus;
     uint8_t *dataOut = NULL; //可以理解位type/typedef 的缩写(有效的维护了代码,比如:一个人用int,一个人用long。最好用typedef来定义)
     size_t dataOutAvailable = 0; //size_t 是操作符sizeof返回的结果类型
     size_t dataOutMoved = 0;

     dataOutAvailable = (dataInLength + kCCBlockSizeDES) & ~(kCCBlockSizeDES - 1);
     dataOut = malloc( dataOutAvailable * sizeof(uint8_t));
     memset((void *)dataOut, 00, dataOutAvailable);//将已开辟内存空间buffer的首 1 个字节的值设为值 0
     const void *vkey = key;
    const void *iv = (const void *) key; //[initIv UTF8String];

    //CCCrypt函数 加密/解密
    ccStatus = CCCrypt(encryptOperation,// 加密/解密
                kCCAlgorithmDES,// 加密根据哪个标准(des,3des,aes。。。。)
                kCCOptionPKCS7Padding,// 选项分组密码算法(des:对每块分组加一次密 3DES:对每块分组加三个不同的密)
                vkey, //密钥 加密和解密的密钥必须一致
                kCCKeySizeDES,// DES 密钥的大小(kCCKeySizeDES=8)
                iv, // 可选的初始矢量
                dataIn, // 数据的存储单元
                dataInLength,// 数据的大小
                (void *)dataOut,// 用于返回数据
                dataOutAvailable,
                &dataOutMoved);

     NSString *result = nil;

     if (encryptOperation == kCCDecrypt)//encryptOperation==1 解码
     {
                 //得到解密出来的data数据,改变为utf-8的字符串
         result = [[NSString alloc] initWithData:[NSData dataWithBytes:(const void *)dataOut length:(NSUInteger)dataOutMoved] encoding:NSUTF8StringEncoding];
    }
     else //encryptOperation==0 (加密过程中,把加好密的数据转成base64的)
     {
         //编码 base64
         NSData *data = [NSData dataWithBytes:(const void *)dataOut length:(NSUInteger)dataOutMoved];
         result = [GTMBase64 stringByEncodingData:data];
     }
    return [result UTF8String];
}

iOS中需要用到的GTMBase64库

如果只需要DES加密的话,将Base64去掉即可

END