python和java中Des加密初试

项目中需要做一个Des加密，牵扯好几家单位，但人家都用java来实现，只用调用相同的代码就好，而我们后台用的python。我初步想到有两种办法来解决这个问题：1、用python来实现des加密功能，保证相同的字符串通过java和python加密出来的密文相同；2、如果第一条行不通，就需要直接利用他们的加密算法，然后想办法用python来调用，以实现加密。

     首先对Des算法做简单了解，见百度百科：数据加密算法。此处对具体实现过程不做讨论。

     接下来看java实现Des加密的算法：

package comcoreutil;
 
javasecurityKey;
javatextSimpleDateFormat;
javautilDate;
 
javaxcryptoBadPaddingException;
javaxcryptoCipher;
javaxcryptoSecretKeyFactory;
javaxcryptospecDESedeKeySpec;
javaxcryptospecIvParameterSpec;
 
sunmiscBASE64Decoder;
sunmiscBASE64Encoder;
 
public DesUtil private final static String encoding ;
    
    private static String getIVTodaynew SimpleDateFormatformatnew Date;
    private static String getIVYesterdaynew SimpleDateFormatformatnew Datenew DategetTime;
    private static String getIVTomorrownew SimpleDateFormatformatnew Datenew DategetTime;
    private static String getSecretKeyTodaygetIVToday;
    private static String getSecretKeyYesterdaygetIVYesterday;
    private static String getSecretKeyTomorrowgetIVTomorrow;
    param plainText
     public static String encodeString plainTextKey deskey null;
        byteencryptData null;
        String secretKey getSecretKeyToday;
        DESedeKeySpec spec new DESedeKeySpecsecretKeygetBytes;
            SecretKeyFactory keyfactory SecretKeyFactorygetInstance;
            deskey keyfactorygenerateSecretspec;
 
            Cipher cipher CiphergetInstance;
            IvParameterSpec ips new IvParameterSpecgetIVTodaygetBytes;
            cipherinitCipherENCRYPT_MODEdeskeyips;
            encryptData cipherdoFinalplainTextgetBytesencoding;
            
            BASE64Encoder base64Encoder new BASE64Encoder;
            base64EncoderencodeencryptData;
        catch eeprintStackTrace;
        ;
    param data
     public static String decodeString dataKey deskey null;
            String secretKey getSecretKeyToday;
            DESedeKeySpec spec new DESedeKeySpecsecretKeygetBytes;
            SecretKeyFactory keyfactory SecretKeyFactorygetInstance;
            deskey keyfactorygenerateSecretspec;
            Cipher deCipher CiphergetInstance;
            IvParameterSpec ips new IvParameterSpecgetIVTodaygetBytes;
            deCipherinitCipherDECRYPT_MODEdeskeyips;
            
            BASE64Decoder base64Decoder new BASE64Decoder;
            bytepasByte null;
            pasBytedeCipherdoFinalbase64DecoderdecodeBufferdata;
            catchBadPaddingException esecretKey getSecretKeyYesterday;
                spec new DESedeKeySpecsecretKeygetBytes;
                deskey keyfactorygenerateSecretspec;
                ips new IvParameterSpecgetIVYesterdaygetBytes;
                deCipherinitCipherDECRYPT_MODEdeskeyips;
                pasBytedeCipherdoFinalbase64DecoderdecodeBufferdata;
                catchBadPaddingException e1secretKey getSecretKeyTomorrow;
                    spec new DESedeKeySpecsecretKeygetBytes;
                    deskey keyfactorygenerateSecretspec;
                    ips new IvParameterSpecgetIVTomorrowgetBytes;
                    deCipherinitCipherDECRYPT_MODEdeskeyips;
                    
                    pasBytedeCipherdoFinalbase64DecoderdecodeBufferdata;
                new StringpasByte;
        catch e;
    public static void mainStringargsSystemoutprintlnDesUtilencode;

以上代码中，最为关键的就是了解Cipher类，3.3.5 Cipher类。

python实现Des加密的基本思路：1、自己重写Des加密算法 python实现DES加密    2、调用pyDes：

pyDes data k triple_desCBCpadpadmodePAD_PKCS5d kencryptdatad
kdecryptdkdecryptdpadmodePAD_PKCS5data

其中triple_des中要求秘钥为16位或24位，des方法需要8位。

但两种形式中，可传递的参数只有需加密字符串和秘钥（长度为8的倍数），并没有java中那个随机向量的概念。由于没有时间研究Cipher的源码，所以用python来实现以上java算法算是泡汤了。下一篇文章说明如何使用JPype实现python调用java代码。