Android实现3DES加密
1. 步骤
常量
private final static String secretKey = "zhuxiaojie123@xx100$#963";//必须是至少24位
- // 向量
- private final static String iv = "12345678";
- // 加解密统一使用的编码方式
- private final static String encoding = "utf-8";
// 向量
private final static String iv = "12345678";
// 加解密统一使用的编码方式
private final static String encoding = "utf-8";- private String data = "这是原始数据将被加密";
private String data = "这是原始数据将被加密";1) 生成3DES算法秘钥
- Key deskey = null;
- DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());
- SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");//定义加密算法，可用des,desede,blowfish
- deskey = keyfactory.generateSecret(spec);//生成秘钥
Key deskey = null;
DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());
SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");//定义加密算法，可用des,desede,blowfish
deskey = keyfactory.generateSecret(spec);//生成秘钥
2) 加密
- Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");// 算法名称/加密模式/填充方式
- IvParameterSpec ips = new IvParameterSpec(iv.getBytes());
- cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
- byte[] encryptData = cipher.doFinal(plainText.getBytes(encoding));
- String encrypt = Base64.encode(encryptData);
Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");// 算法名称/加密模式/填充方式
IvParameterSpec ips = new IvParameterSpec(iv.getBytes());
cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
byte[] encryptData = cipher.doFinal(plainText.getBytes(encoding));
String encrypt = Base64.encode(encryptData);3)解密
解密获取算法秘钥和加密过程的获取算法秘钥过程一样，不同的如下
- 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));
- String decrypt = new String(decryptData,encoding);
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));
String decrypt = new String(decryptData,encoding);4) 整理
- /**
- * 3DES加密
- * @param plainText 待加密文本
- * @param secretKey 约定的key,至少24位，例如：String secretKey = "zhuxiaojie123@lx100$#365";
- * @param iv 向量 例如： String iv = "12345678";
- * @return 密文
- * @throws Exception : 如果secretKey小于24位，InvalidKeyException
- */
- public static String encrypt(String plainText,String secretKey,String iv) 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加密
* @param plainText 待加密文本
* @param secretKey 约定的key,至少24位，例如：String secretKey = "zhuxiaojie123@lx100$#365";
* @param iv 向量 例如： String iv = "12345678";
* @return 密文
* @throws Exception : 如果secretKey小于24位，InvalidKeyException
*/
public static String encrypt(String plainText,String secretKey,String iv) 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 密文
- * @param secretKey 加密时的key
- * @param iv 加密时使用的向量
- * @return 返回解密后的明文
- * @throws Exception
- */
- public static String decrypt(String encryptText,String secretKey,String iv) 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);
- }
/**
* 3DES解密
* @param encryptText 密文
* @param secretKey 加密时的key
* @param iv 加密时使用的向量
* @return 返回解密后的明文
* @throws Exception
*/
public static String decrypt(String encryptText,String secretKey,String iv) 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);
}- import java.io.ByteArrayOutputStream;
- import java.io.IOException;
- import java.io.OutputStream;
- /**
- * Base64编码工具类
- *
- */
- 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;
- }
- }
- }
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
/**
* Base64编码工具类
*
*/
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;
}
}
}
2. 3DES的加密、解密模式
CBC (key,iv,data)
ECB (key,data)
3. 补码方式
- Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");// 算法名称/加密模式/填充方式
Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");// 算法名称/加密模式/填充方式 - Cipher cipher = Cipher.getInstance("desede/ECB/PKCS5Padding");
Cipher cipher = Cipher.getInstance("desede/ECB/PKCS5Padding");
4. 加密后处理
为防止3DES加密后产生乱码，对加密后的数据使用Base64.decode()一下。同样的，解密前，对数据先Base64.decode();
- Base64.encode(encryptData);
Base64.encode(encryptData);- Base64.decode(encryptText);
Base64.decode(encryptText);
5.注意：加密和解密方法，客户端和后台要使用同一套。不然很难调试的。即使是同一串加密源和key，每次加密出来的密文也都是不一样的。