先前一直在做安卓,最近要开发iPhone客户端,这其中遇到的最让人纠结的要属Java、Android和iPhone三个平台加解密不一致的问题。因为手机端后台通常是用JAVA开发的Web Service,Android和iPhone客户端调用同样的Web Service接口,为了数据安全考虑,要对数据进行加密。头疼的问题就来了,很难编写出一套加密程序,在3个平台间加解密的结果一致,总不能为Android和iPhone两个客户端各写一套Web Service接口吧?我相信还会有很多朋友为此困惑,在此分享一套3DES加密程序,能够实现Java、Android和iPhone三个平台加解密一致。

       首先是JAVA端的加密工具类,它同样适用于Android端,无需任何修改,即可保证Java与Android端的加解密一致,并且中文不会乱码。


双击代码全选

package          org.liuyq.des3;           


                    


          import          java.security.Key;           


                    


          import          javax.crypto.Cipher;           


          import          javax.crypto.SecretKeyFactory;           


          import          javax.crypto.spec.DESedeKeySpec;           


          import          javax.crypto.spec.IvParameterSpec;           


                    


          /**          


                    * 3DES加密工具类          


                    *           


                    * @author liufeng           


                    * @date 2012-10-11          


                    */         


          public          class          Des3 {           


                    // 密钥           


                    private          final          static          String secretKey =           "liuyunqiang@lx100$#365#$"          ;           


                    // 向量           


                    private          final          static          String iv =           "01234567"          ;           


                    // 加解密统一使用的编码方式           


                    private          final          static          String encoding =           "utf-8"          ;           


                    


                    /**          


                    * 3DES加密          


                    *           


                    * @param plainText 普通文本          


                    * @return          


                    * @throws Exception           


                    */         


                    public          static          String encode(String plainText)           throws          Exception {           


                    Key deskey =           null          ;           


                    DESedeKeySpec spec =           new          DESedeKeySpec(secretKey.getBytes());           


                    SecretKeyFactory keyfactory = SecretKeyFactory.getInstance(          "desede"          );           


                    deskey = keyfactory.generateSecret(spec);           


                    


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


                    IvParameterSpec ips =           new          IvParameterSpec(iv.getBytes());           


                    cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);           


                    byte          [] encryptData = cipher.doFinal(plainText.getBytes(encoding));           


                    return          Base64.encode(encryptData);           


                    }           


                    


                    /**          


                    * 3DES解密          


                    *           


                    * @param encryptText 加密文本          


                    * @return          


                    * @throws Exception          


                    */         


                    public          static          String decode(String encryptText)           throws          Exception {           


                    Key deskey =           null          ;           


                    DESedeKeySpec spec =           new          DESedeKeySpec(secretKey.getBytes());           


                    SecretKeyFactory keyfactory = SecretKeyFactory.getInstance(          "desede"          );           


                    deskey = keyfactory.generateSecret(spec);           


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


                    IvParameterSpec ips =           new          IvParameterSpec(iv.getBytes());           


                    cipher.init(Cipher.DECRYPT_MODE, deskey, ips);           


                    


                    byte          [] decryptData = cipher.doFinal(Base64.decode(encryptText));           


                    


                    return          new          String(decryptData, encoding);           


                    }           


          }




上面的加密工具类会使用到Base64这个类,该类的源代码如下:



双击代码全选

package          org.liuyq.des3;           


          import          java.io.ByteArrayOutputStream;           


          import          java.io.IOException;           


          import          java.io.OutputStream;           


                    


          /**          


                    * Base64编码工具类          


                    *           


                    * @author liufeng           


                    * @date 2012-10-11          


                    */         


          public          class          Base64 {           


                    private          static          final          char          [] legalChars =           "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"          .toCharArray();           


                    


                    public          static          String encode(          byte          [] data) {           


                    int          start =           0          ;           


                    int          len = data.length;           


                    StringBuffer buf =           new          StringBuffer(data.length *           3          /           2          );           


                    


                    int          end = len -           3          ;           


                    int          i = start;           


                    int          n =           0          ;           


                    


                    while          (i <= end) {           


                    int          d = ((((          int          ) data[i]) &           0x0ff          ) <<           16          ) | ((((          int          ) data[i +           1          ]) &           0x0ff          ) <<           8          ) | (((          int          ) data[i +           2          ]) &           0x0ff          );           


                    


                    buf.append(legalChars[(d >>           18          ) &           63          ]);           


                    buf.append(legalChars[(d >>           12          ) &           63          ]);           


                    buf.append(legalChars[(d >>           6          ) &           63          ]);           


                    buf.append(legalChars[d &           63          ]);           


                    


                    i +=           3          ;           


                    


                    if          (n++ >=           14          ) {           


                    n =           0          ;           


                    buf.append(          " "          );           


                    }           


                    }           


                    


                    if          (i == start + len -           2          ) {           


                    int          d = ((((          int          ) data[i]) &           0x0ff          ) <<           16          ) | ((((          int          ) data[i +           1          ]) &           255          ) <<           8          );           


                    


                    buf.append(legalChars[(d >>           18          ) &           63          ]);           


                    buf.append(legalChars[(d >>           12          ) &           63          ]);           


                    buf.append(legalChars[(d >>           6          ) &           63          ]);           


                    buf.append(          "="          );           


                    }           else          if          (i == start + len -           1          ) {           


                    int          d = (((          int          ) data[i]) &           0x0ff          ) <<           16          ;           


                    


                    buf.append(legalChars[(d >>           18          ) &           63          ]);           


                    buf.append(legalChars[(d >>           12          ) &           63          ]);           


                    buf.append(          "=="          );           


                    }           


                    


                    return          buf.toString();           


                    }           


                    


                    private          static          int          decode(          char          c) {           


                    if          (c >=           'A'          && c <=           'Z'          )           


                    return          ((          int          ) c) -           65          ;           


                    else          if          (c >=           'a'          && c <=           'z'          )           


                    return          ((          int          ) c) -           97          +           26          ;           


                    else          if          (c >=           '0'          && c <=           '9'          )           


                    return          ((          int          ) c) -           48          +           26          +           26          ;           


                    else         


                    switch          (c) {           


                    case          '+'          :           


                    return          62          ;           


                    case          '/'          :           


                    return          63          ;           


                    case          '='          :           


                    return          0          ;           


                    default          :           


                    throw          new          RuntimeException(          "unexpected code: "          + c);           


                    }           


                    }           


                    


                    /**          


                    * Decodes the given Base64 encoded String to a new byte array. The byte array holding the decoded data is returned.          


                    */         


                    


                    public          static          byte          [] decode(String s) {           


                    


                    ByteArrayOutputStream bos =           new          ByteArrayOutputStream();           


                    try          {           


                    decode(s, bos);           


                    }           catch          (IOException e) {           


                    throw          new          RuntimeException();           


                    }           


                    byte          [] decodedBytes = bos.toByteArray();           


                    try          {           


                    bos.close();           


                    bos =           null          ;           


                    }           catch          (IOException ex) {           


                    System.err.println(          "Error while decoding BASE64: "          + ex.toString());           


                    }           


                    return          decodedBytes;           


                    }           


                    


                    private          static          void          decode(String s, OutputStream os)           throws          IOException {           


                    int          i =           0          ;           


                    


                    int          len = s.length();           


                    


                    while          (          true          ) {           


                    while          (i < len && s.charAt(i) <=           ' '          )           


                    i++;           


                    


                    if          (i == len)           


                    break          ;           


                    


                    int          tri = (decode(s.charAt(i)) <<           18          ) + (decode(s.charAt(i +           1          )) <<           12          ) + (decode(s.charAt(i +           2          )) <<           6          ) + (decode(s.charAt(i +           3          )));           


                    


                    os.write((tri >>           16          ) &           255          );           


                    if          (s.charAt(i +           2          ) ==           '='          )           


                    break          ;           


                    os.write((tri >>           8          ) &           255          );           


                    if          (s.charAt(i +           3          ) ==           '='          )           


                    break          ;           


                    os.write(tri &           255          );           


                    


                    i +=           4          ;           


                    }           


                    }           


          }




  接下来是iPhone端的加密程序,当然是用Ojbective-C写的3DES加密程序,源代码如下:



双击代码全选

//           


          //  DES3Util.h           


          //  lx100-gz           


          //           


          //  Created by  柳峰 on 12-10-10.           


          //  Copyright 2012 .         


          //           


                    


          #import <Foundation/Foundation.h>           


                    


                    


          @interface DES3Util : NSObject {           


                    


          }           


                    


          // 加密方法           


          + (NSString*)encrypt:(NSString*)plainText;           


                    


          // 解密方法           


          + (NSString*)decrypt:(NSString*)encryptText;           


                    


          @end



双击代码全选

//           


          //  DES3Util.m           


          //  lx100-gz           


          //           


          //  Created by  柳峰 on 12-9-17.           


          //  Copyright 2012 .         


          //           


                    


          #import "DES3Util.h"           


          #import <CommonCrypto/CommonCryptor.h>           


          #import "GTMBase64.h"           


                    


          #define gkey            @"liuyunqiang@lx100$#365#$"           


          #define gIv             @"01234567"           


                    


          @implementation DES3Util           


                    


          // 加密方法           


          + (NSString*)encrypt:(NSString*)plainText {           


                    NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];           


                    size_t plainTextBufferSize = [data length];           


                    const void *vplainText = (const void *)[data bytes];           


                    


                    CCCryptorStatus ccStatus;           


                    uint8_t *bufferPtr = NULL;           


                    size_t bufferPtrSize = 0;           


                    size_t movedBytes = 0;           


                    


                    bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);           


                    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));           


                    memset((void *)bufferPtr, 0x0, bufferPtrSize);           


                    


                    const void *vkey = (const void *) [gkey UTF8String];           


                    const void *vinitVec = (const void *) [gIv UTF8String];           


                    


                    ccStatus = CCCrypt(kCCEncrypt,           


                    kCCAlgorithm3DES,           


                    kCCOptionPKCS7Padding,           


                    vkey,           


                    kCCKeySize3DES,           


                    vinitVec,           


                    vplainText,           


                    plainTextBufferSize,           


                    (void *)bufferPtr,           


                    bufferPtrSize,           


                    &movedBytes);           


                    


                    NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];           


                    NSString *result = [GTMBase64 stringByEncodingData:myData];           


                    return result;           


          }           


                    


          // 解密方法           


          + (NSString*)decrypt:(NSString*)encryptText {           


                    NSData *encryptData = [GTMBase64 decodeData:[encryptText dataUsingEncoding:NSUTF8StringEncoding]];           


                    size_t plainTextBufferSize = [encryptData length];           


                    const void *vplainText = [encryptData bytes];           


                    


                    CCCryptorStatus ccStatus;           


                    uint8_t *bufferPtr = NULL;           


                    size_t bufferPtrSize = 0;           


                    size_t movedBytes = 0;           


                    


                    bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);           


                    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));           


                    memset((void *)bufferPtr, 0x0, bufferPtrSize);           


                    


                    const void *vkey = (const void *) [gkey UTF8String];           


                    const void *vinitVec = (const void *) [gIv UTF8String];           


                    


                    ccStatus = CCCrypt(kCCDecrypt,           


                    kCCAlgorithm3DES,           


                    kCCOptionPKCS7Padding,           


                    vkey,           


                    kCCKeySize3DES,           


                    vinitVec,           


                    vplainText,           


                    plainTextBufferSize,           


                    (void *)bufferPtr,           


                    bufferPtrSize,           


                    &movedBytes);           


                    


                    NSString *result = [[[NSString alloc] initWithData:[NSData dataWithBytes:(const void *)bufferPtr            


                    length:(NSUInteger)movedBytes] encoding:NSUTF8StringEncoding] autorelease];           


                    return result;           


          }           


                    


          @end




iPhone端的加密工具类中引入了“GTMBase64.h”,这是iOS平台的Base64编码工具类,见附件

       好了,赶紧试一下吧,JAVA,Android和iPhone三个平台的加密不一致问题是不是解决了呢?以上为3DES加密,也可将其改为AES加密。其实,对此问题,还有一种更好的实现方式,那就是用C语言写一套加密程序,这样在iOS平台是可以直接使用C程序的,而在Java和Android端通过JNI去调用C语言编写的加密方法,这是不是就实现了3个平台调用同一套加密程序呢?