學習筆記，JAVA 3DES 加解密學習

引入 bouncycastle-jce-jdk13-112.jar  [ 在我的資原始檔中可以進行下載 ]

import java.security.Security;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

public class Double3DES {
	
	
	public static byte[] strToBCDBytes(String str,boolean isLeft) {		
		if( str == null || "".equals(str.replaceAll("　"," ").trim())){			
			return null;
		}
		int len = str.length();    
		int mod = len % 2;   

		if (mod != 0) {   
			if(isLeft){
				str =  str + "0";
			}else{
				str = "0" + str;
			}
			len = str.length();    
		}
		byte abt[] = new byte[len];    
		if (len >= 2) {    
			len = len / 2;    
		}
		byte bbt[] = new byte[len];    
		abt = str.getBytes();    
		int j, k;   

		for (int p = 0; p < str.length()/2; p++) {    
			if ( (abt[2 * p] >= '0') && (abt[2 * p] <= '9')) {    
				j = abt[2 * p] - '0';    
			} else if ( (abt[2 * p] >= 'a') && (abt[2 * p] <= 'z')) {    
				j = abt[2 * p] - 'a' + 0x0a;    
			} else {    
				j = abt[2 * p] - 'A' + 0x0a;    
			}
			if ( (abt[2 * p + 1] >= '0') && (abt[2 * p + 1] <= '9')) {    
				k = abt[2 * p + 1] - '0';    
			} else if ( (abt[2 * p + 1] >= 'a') && (abt[2 * p + 1] <= 'z')) {    
				k = abt[2 * p + 1] - 'a' + 0x0a;    
			}else {    
				k = abt[2 * p + 1] - 'A' + 0x0a;    
			}
			int a = (j << 4) + k;    
			byte b = (byte) a;    
			bbt[p] = b;    
		}    
		return bbt;    
	} 	
	
		
	private static byte uniteBytes(String src0, String src1) {
		byte b0 = Byte.decode("0x" + src0).byteValue();
		b0 = (byte) (b0 << 4);
		byte b1 = Byte.decode("0x" + src1).byteValue();
		byte ret = (byte) (b0 | b1);
		return ret;
	}

	
	/**
	 * 十六進位制字串轉換成bytes
	 * 
	 * @param src
	 * @return
	 */
	public static byte[] hexStr2Bytes(String src) {
		int m = 0, n = 0;
		int l = src.length() / 2;
		byte[] ret = new byte[l];
		for (int i = 0; i < l; i++) {
			m = i * 2 + 1;
			n = m + 1;
			ret[i] = uniteBytes(src.substring(i * 2, m), src.substring(m, n));
		}
		return ret;
	}
	
	public static String byte2HexStr(byte[] b) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = (Integer.toHexString(b[n] & 0XFF));
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
		}
		return hs.toUpperCase();
	}
	
	/**
	 * 
	 * @param mainKey  主金鑰
	 * @param plainKey 
	 * @param isEncry true 表示加密   false 表示解密
	 * @return
	 */
	public static String desOrEncryptKey(String mainKey,String plainKey,boolean isEncry){  
        String descryptKey = "";  
        try{  
            Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());   
            String Algorithm = "DESede/ECB/NoPadding";   
            byte[] hb = strToBCDBytes(mainKey, true);                     
            byte[] k = new byte[24];  
            System.arraycopy(hb,0,k,0,16);  
            System.arraycopy(hb,0,k,16,8);    
            SecretKey deskey = new SecretKeySpec(k, Algorithm);  
            Cipher c1 = Cipher.getInstance(Algorithm);  
            if(isEncry){
            	c1.init(Cipher.ENCRYPT_MODE, deskey);
            }else{
            	c1.init(Cipher.DECRYPT_MODE, deskey); 
            }
            descryptKey = byte2HexStr((c1.doFinal(hexStr2Bytes(plainKey))));  
        }catch(Exception e){  
           e.printStackTrace();
        }  
        return descryptKey;  
    }
	
	
	/**
	 * 
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {
		//加密
		System.out.println("\tencryp:::: "+desOrEncryptKey("11111113111111710123456789ABCDEF","ADF55D08B48B18E3BDF55D08D48B18E3",true));
		//解密
		System.out.println("\tdescryp:::: "+desOrEncryptKey("11111113111111710123456789ABCDEF","ADF55D08B48B18E3BDF55D08D48B18E3",false));
	}
	
}