Android、iPhone和Java三个平台一致的加密工具

1import java.security.Key;  
2  
3import javax.crypto.Cipher;  
4import javax.crypto.SecretKeyFactory;  
5import javax.crypto.spec.DESedeKeySpec;  
6import javax.crypto.spec.IvParameterSpec;  
7  
8/** 
9 * 3DES加密工具类 
10 *  
11 * @author liufeng  
12 * @date 2012-10-11 
13 */  
14public class Des3 {  
15    // 密钥  
16    private final static String secretKey = "liuyunqiang@lx100$#365#$";  
17    // 向量  
18    private final static String iv = "01234567";  
19    // 加解密统一使用的编码方式  
20    private final static String encoding = "utf-8";  
21  
22    /** 
23     * 3DES加密 
24     *  
25     * @param plainText 普通文本 
26     * @return 
27     * @throws Exception  
28     */  
29    public static String encode(String plainText) throws Exception {  
30        Key deskey = null;  
31        DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());  
32        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");  
33        deskey = keyfactory.generateSecret(spec);  
34  
35        Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");  
36        IvParameterSpec ips = new IvParameterSpec(iv.getBytes());  
37        cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);  
38        byte[] encryptData = cipher.doFinal(plainText.getBytes(encoding));  
39        return Base64.encode(encryptData);  
40    }  
41  
42    /** 
43     * 3DES解密 
44     *  
45     * @param encryptText 加密文本 
46     * @return 
47     * @throws Exception 
48     */  
49    public static String decode(String encryptText) throws Exception {  
50        Key deskey = null;  
51        DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());  
52        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");  
53        deskey = keyfactory.generateSecret(spec);  
54        Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");  
55        IvParameterSpec ips = new IvParameterSpec(iv.getBytes());  
56        cipher.init(Cipher.DECRYPT_MODE, deskey, ips);  
57  
58        byte[] decryptData = cipher.doFinal(Base64.decode(encryptText));  
59  
60        return new String(decryptData, encoding);  
61    }  
62}  

上面的加密工具类会使用到Base64这个类，该类的源代码如下：

1import java.io.ByteArrayOutputStream;  
2import java.io.IOException;  
3import java.io.OutputStream;  
4  
5/** 
6 * Base64编码工具类 
7 *  
8 * @author liufeng  
9 * @date 2012-10-11 
10 */  
11public class Base64 {  
12    private static final char[] legalChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray();  
13  
14    public static String encode(byte[] data) {  
15        int start = 0;  
16        int len = data.length;  
17        StringBuffer buf = new StringBuffer(data.length * 3 / 2);  
18  
19        int end = len - 3;  
20        int i = start;  
21        int n = 0;  
22  
23        while (i <= end) {  
24            int d = ((((int) data[i]) & 0x0ff) << 16) | ((((int) data[i + 1]) & 0x0ff) << 8) | (((int) data[i + 2]) & 0x0ff);  
25  
26            buf.append(legalChars[(d >> 18) & 63]);  
27            buf.append(legalChars[(d >> 12) & 63]);  
28            buf.append(legalChars[(d >> 6) & 63]);  
29            buf.append(legalChars[d & 63]);  
30  
31            i += 3;  
32  
33            if (n++ >= 14) {  
34                n = 0;  
35                buf.append(" ");  
36            }  
37        }  
38  
39        if (i == start + len - 2) {  
40            int d = ((((int) data[i]) & 0x0ff) << 16) | ((((int) data[i + 1]) & 255) << 8);  
41  
42            buf.append(legalChars[(d >> 18) & 63]);  
43            buf.append(legalChars[(d >> 12) & 63]);  
44            buf.append(legalChars[(d >> 6) & 63]);  
45            buf.append("=");  
46        } else if (i == start + len - 1) {  
47            int d = (((int) data[i]) & 0x0ff) << 16;  
48  
49            buf.append(legalChars[(d >> 18) & 63]);  
50            buf.append(legalChars[(d >> 12) & 63]);  
51            buf.append("==");  
52        }  
53  
54        return buf.toString();  
55    }  
56  
57    private static int decode(char c) {  
58        if (c >= 'A' && c <= 'Z')  
59            return ((int) c) - 65;  
60        else if (c >= 'a' && c <= 'z')  
61            return ((int) c) - 97 + 26;  
62        else if (c >= '0' && c <= '9')  
63            return ((int) c) - 48 + 26 + 26;  
64        else  
65            switch (c) {  
66            case '+':  
67                return 62;  
68            case '/':  
69                return 63;  
70            case '=':  
71                return 0;  
72            default:  
73                throw new RuntimeException("unexpected code: " + c);  
74            }  
75    }  
76  
77    /** 
78     * Decodes the given Base64 encoded String to a new byte array. The byte array holding the decoded data is returned. 
79     */  
80  
81    public static byte[] decode(String s) {  
82  
83        ByteArrayOutputStream bos = new ByteArrayOutputStream();  
84        try {  
85            decode(s, bos);  
86        } catch (IOException e) {  
87            throw new RuntimeException();  
88        }  
89        byte[] decodedBytes = bos.toByteArray();  
90        try {  
91            bos.close();  
92            bos = null;  
93        } catch (IOException ex) {  
94            System.err.println("Error while decoding BASE64: " + ex.toString());  
95        }  
96        return decodedBytes;  
97    }  
98  
99    private static void decode(String s, OutputStream os) throws IOException {  
100        int i = 0;  
101  
102        int len = s.length();  
103  
104        while (true) {  
105            while (i < len && s.charAt(i) <= ' ')  
106                i++;  
107  
108            if (i == len)  
109                break;  
110  
111            int tri = (decode(s.charAt(i)) << 18) + (decode(s.charAt(i + 1)) << 12) + (decode(s.charAt(i + 2)) << 6) + (decode(s.charAt(i + 3)));  
112  
113            os.write((tri >> 16) & 255);  
114            if (s.charAt(i + 2) == '=')  
115                break;  
116            os.write((tri >> 8) & 255);  
117            if (s.charAt(i + 3) == '=')  
118                break;  
119            os.write(tri & 255);  
120  
121            i += 4;  
122        }  
123    }  
124}  

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：

1//  
2//  DES3Util.h  
3//  lx100-gz  
4//  
5//  Created by  柳峰 on 12-10-10.  
6//  Copyright 2012 http://blog.csdn.net/lyq8479. All rights reserved.  
7//  
8  
9#import <Foundation/Foundation.h>  
10  
11  
12@interface DES3Util : NSObject {  
13  
14}  
15  
16// 加密方法  
17+ (NSString*)encrypt:(NSString*)plainText;  
18  
19// 解密方法  
20+ (NSString*)decrypt:(NSString*)encryptText;  
21  
22@end  
23
24
25//  
26//  DES3Util.m  
27//  lx100-gz  
28//  
29//  Created by  柳峰 on 12-9-17.  
30//  Copyright 2012 http://blog.csdn.net/lyq8479. All rights reserved.  
31//  
32  
33#import "DES3Util.h"  
34#import <CommonCrypto/CommonCryptor.h>  
35#import "GTMBase64.h"  
36  
37#define gkey            @"liuyunqiang@lx100$#365#$"  
38#define gIv             @"01234567"  
39  
40@implementation DES3Util  
41  
42// 加密方法  
43+ (NSString*)encrypt:(NSString*)plainText {  
44    NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];  
45    size_t plainTextBufferSize = [data length];  
46    const void *vplainText = (const void *)[data bytes];  
47      
48    CCCryptorStatus ccStatus;  
49    uint8_t *bufferPtr = NULL;  
50    size_t bufferPtrSize = 0;  
51    size_t movedBytes = 0;  
52      
53    bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);  
54    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));  
55    memset((void *)bufferPtr, 0x0, bufferPtrSize);  
56      
57    const void *vkey = (const void *) [gkey UTF8String];  
58    const void *vinitVec = (const void *) [gIv UTF8String];  
59      
60    ccStatus = CCCrypt(kCCEncrypt,  
61                       kCCAlgorithm3DES,  
62                       kCCOptionPKCS7Padding,  
63                       vkey,  
64                       kCCKeySize3DES,  
65                       vinitVec,  
66                       vplainText,  
67                       plainTextBufferSize,  
68                       (void *)bufferPtr,  
69                       bufferPtrSize,  
70                       &movedBytes);  
71      
72    NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];  
73    NSString *result = [GTMBase64 stringByEncodingData:myData];  
74    return result;  
75}  
76  
77// 解密方法  
78+ (NSString*)decrypt:(NSString*)encryptText {  
79    NSData *encryptData = [GTMBase64 decodeData:[encryptText dataUsingEncoding:NSUTF8StringEncoding]];  
80    size_t plainTextBufferSize = [encryptData length];  
81    const void *vplainText = [encryptData bytes];  
82      
83    CCCryptorStatus ccStatus;  
84    uint8_t *bufferPtr = NULL;  
85    size_t bufferPtrSize = 0;  
86    size_t movedBytes = 0;  
87      
88    bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);  
89    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));  
90    memset((void *)bufferPtr, 0x0, bufferPtrSize);  
91      
92    const void *vkey = (const void *) [gkey UTF8String];  
93    const void *vinitVec = (const void *) [gIv UTF8String];  
94      
95    ccStatus = CCCrypt(kCCDecrypt,  
96                       kCCAlgorithm3DES,  
97                       kCCOptionPKCS7Padding,  
98                       vkey,  
99                       kCCKeySize3DES,  
100                       vinitVec,  
101                       vplainText,  
102                       plainTextBufferSize,  
103                       (void *)bufferPtr,  
104                       bufferPtrSize,  
105                       &movedBytes);  
106      
107    NSString *result = [[[NSString alloc] initWithData:[NSData dataWithBytes:(const void *)bufferPtr   
108                                length:(NSUInteger)movedBytes] encoding:NSUTF8StringEncoding] autorelease];  
109    return result;  
110}  
111  
112@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，就不在这里贴出相关代码了，需要的百度一下就能找到，实在找不到就回复留言给我。

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？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？