package com;
import ;
import ;
import ;
import ;
import ;
import ;
import ;
import ;
import ;
import ;
import .PKCS8EncodedKeySpec;
import .X509EncodedKeySpec;
import ;
import ;
import ;
import ;
import .BASE64Decoder;
import .BASE64Encoder;
public class CreateSecretKey {
public static final String KEY_ALGORITHM = "RSA";
private static final String PUBLIC_KEY = "RSAPublicKey";
private static final String PRIVATE_KEY = "RSAPrivateKey";
public static final String SIGNATURE_ALGORITHM="MD5withRSA";
/**
* RSA最大加密明文大小
*/
private static final int MAX_ENCRYPT_BLOCK = 117;
/**
* RSA最大解密密文大小
*/
private static final int MAX_DECRYPT_BLOCK = 128;
//获得公钥字符串
public static String getPublicKeyStr(Map<String, Object> keyMap) throws Exception {
//获得map中的公钥对象 转为key对象
Key key = (Key) (PUBLIC_KEY);
//编码返回字符串
return encryptBASE64(());
}
//获得私钥字符串
public static String getPrivateKeyStr(Map<String, Object> keyMap) throws Exception {
//获得map中的私钥对象 转为key对象
Key key = (Key) (PRIVATE_KEY);
//编码返回字符串
return encryptBASE64(());
}
//获取公钥
public static PublicKey getPublicKey(String key) throws Exception {
byte[] keyBytes;
keyBytes = (new BASE64Decoder()).decodeBuffer(key);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
KeyFactory keyFactory = (KEY_ALGORITHM);
PublicKey publicKey = (keySpec);
return publicKey;
}
//获取私钥
public static PrivateKey getPrivateKey(String key) throws Exception {
byte[] keyBytes;
keyBytes = (new BASE64Decoder()).decodeBuffer(key);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
KeyFactory keyFactory = (KEY_ALGORITHM);
PrivateKey privateKey = (keySpec);
return privateKey;
}
//解码返回byte
public static byte[] decryptBASE64(String key) throws Exception {
return (new BASE64Decoder()).decodeBuffer(key);
}
//编码返回字符串
public static String encryptBASE64(byte[] key) throws Exception {
return (new BASE64Encoder()).encodeBuffer(key);
}
//***************************签名和验证*******************************
public static byte[] sign(byte[] data,String privateKeyStr) throws Exception{
PrivateKey priK = getPrivateKey(privateKeyStr);
Signature sig = (SIGNATURE_ALGORITHM);
(priK);
(data);
return ();
}
public static boolean verify(byte[] data,byte[] sign,String publicKeyStr) throws Exception{
PublicKey pubK = getPublicKey(publicKeyStr);
Signature sig = (SIGNATURE_ALGORITHM);
(pubK);
(data);
return (sign);
}
//************************加密解密**************************
public static byte[] encrypt(byte[] plainText,String publicKeyStr)throws Exception{
PublicKey publicKey = getPublicKey(publicKeyStr);
Cipher cipher = (KEY_ALGORITHM);
(Cipher.ENCRYPT_MODE, publicKey);
int inputLen = ;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
int i = 0;
byte[] cache;
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {
cache = (plainText, offSet, MAX_ENCRYPT_BLOCK);
} else {
cache = (plainText, offSet, inputLen - offSet);
}
(cache, 0, );
i++;
offSet = i * MAX_ENCRYPT_BLOCK;
}
byte[] encryptText = ();
();
return encryptText;
}
public static byte[] decrypt(byte[] encryptText,String privateKeyStr)throws Exception{
PrivateKey privateKey = getPrivateKey(privateKeyStr);
Cipher cipher = (KEY_ALGORITHM);
(Cipher.DECRYPT_MODE, privateKey);
int inputLen = ;
ByteArrayOutputStream out = new ByteArrayOutputStream();
int offSet = 0;
byte[] cache;
int i = 0;
// 对数据分段解密
while (inputLen - offSet > 0) {
if (inputLen - offSet > MAX_DECRYPT_BLOCK) {
cache = (encryptText, offSet, MAX_DECRYPT_BLOCK);
} else {
cache = (encryptText, offSet, inputLen - offSet);
}
(cache, 0, );
i++;
offSet = i * MAX_DECRYPT_BLOCK;
}
byte[] plainText = ();
();
return plainText;
}
public static void main(String[] args) {
Map<String, Object> keyMap;
byte[] cipherText;
String input = "Hello World!";
try {
keyMap = initKey();
String publicKey = getPublicKeyStr(keyMap);
("公钥------------------");
(publicKey);
String privateKey = getPrivateKeyStr(keyMap);
("私钥------------------");
(privateKey);
("测试可行性-------------------");
("明文======="+input);
cipherText = encrypt((),publicKey);
//加密后的东西
("密文======="+new String(cipherText));
//开始解密
byte[] plainText = decrypt(cipherText,privateKey);
("解密后明文===== " + new String(plainText));
("验证签名-----------");
String str="被签名的内容";
("\n原文:"+str);
byte[] signature=sign((),privateKey);
boolean status=verify((), signature,publicKey);
("验证情况："+status);
} catch (Exception e) {
();
}
}
}
