一般為了安全采用的是私鑰加密，公鑰解密（公鑰可以用Base64轉換後公開）
package com.chitic.supplywater.common.service;
import org.apache.commons.codec.binary.Base64;
import javax.crypto.Cipher;
import java.security.*;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Arrays;
/**
* <p>
* 封裝同RSA非對稱加密算法有關的方法，可用于數字簽名，RSA加密解密
* </p>
*
* @Copyright:WDSsoft
*/
public class RSATool {
public RSATool() {
}
/**
* 使用私鑰加密資料
* 用一個已打包成byte[]形式的私鑰加密資料，即數字簽名
*
* @param keyInByte 打包成byte[]的私鑰
* @param source 要簽名的資料，一般應是數字摘要
* @return 簽名 byte[]
*/
public static byte[] sign(byte[] keyInByte, byte[] source) {
try {
PKCS8EncodedKeySpec priv_spec = new PKCS8EncodedKeySpec(keyInByte);
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
PrivateKey privKey = mykeyFactory.generatePrivate(priv_spec);
Signature sig = Signature.getInstance("SHA1withRSA");
sig.initSign(privKey);
sig.update(source);
return sig.sign();
} catch (Exception e) {
return null;
}
}
/**
* 驗證數字簽名
*
* @param keyInByte 打包成byte[]形式的公鑰
* @param source 原文的數字摘要
* @param sign 簽名（對原文的數字摘要的簽名）
* @return 是否證明 boolean
*/
public static boolean verify(byte[] keyInByte, byte[] source, byte[] sign) {
try {
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
Signature sig = Signature.getInstance("SHA1withRSA");
X509EncodedKeySpec pub_spec = new X509EncodedKeySpec(keyInByte);
PublicKey pubKey = mykeyFactory.generatePublic(pub_spec);
sig.initVerify(pubKey);
sig.update(source);
return sig.verify(sign);
} catch (Exception e) {
return false;
}
}
/**
* 建立新的密鑰對，傳回打包的byte[]形式私鑰和公鑰
*
* @return 包含打包成byte[]形式的私鑰和公鑰的object[], 其中，object[0]為私鑰byte[],object[1]為公鑰byte[]
*/
public static Object[] giveRSAKeyPairInByte() {
KeyPair newKeyPair = creatmyKey();
if (newKeyPair == null) {
return null;
}
Object[] re = new Object[2];
if (newKeyPair != null) {
PrivateKey priv = newKeyPair.getPrivate();
byte[] b_priv = priv.getEncoded();
PublicKey pub = newKeyPair.getPublic();
byte[] b_pub = pub.getEncoded();
re[0] = b_priv;
re[1] = b_pub;
return re;
}
return null;
}
/**
* 建立密鑰對
*
* @return KeyPair對象
*/
public static KeyPair creatmyKey() {
KeyPair myPair;
long mySeed;
mySeed = System.currentTimeMillis();
try {
KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
SecureRandom random = SecureRandom.getInstance("SHA1PRNG", "SUN");
random.setSeed(mySeed);
keyGen.initialize(1024, random);
myPair = keyGen.generateKeyPair();
} catch (Exception e1) {
return null;
}
return myPair;
}
/**
* 使用RSA公鑰加密資料
*
* @param pubKeyInByte 打包的byte[]形式公鑰
* @param data 要加密的資料
* @return 加密資料
*/
public static byte[] encryptByRSA(byte[] pubKeyInByte, byte[] data) {
try {
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
X509EncodedKeySpec pub_spec = new X509EncodedKeySpec(pubKeyInByte);
PublicKey pubKey = mykeyFactory.generatePublic(pub_spec);
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
return cipher.doFinal(data);
} catch (Exception e) {
return null;
}
}
/**
* 用RSA私鑰解密
*
* @param privKeyInByte 私鑰打包成byte[]形式
* @param data 要解密的資料
* @return 解密資料
*/
public static byte[] decryptByRSA(byte[] privKeyInByte, byte[] data) {
try {
PKCS8EncodedKeySpec priv_spec = new PKCS8EncodedKeySpec(
privKeyInByte);
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
PrivateKey privKey = mykeyFactory.generatePrivate(priv_spec);
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
cipher.init(Cipher.DECRYPT_MODE, privKey);
return cipher.doFinal(data);
} catch (Exception e) {
return null;
}
}
/**
* 使用RSA私鑰加密資料
*
* @param privKeyInByte 打包的byte[]形式私鑰
* @param data 要加密的資料
* @return 加密資料
*/
public static byte[] encryptByRSA1(byte[] privKeyInByte, byte[] data) {
try {
PKCS8EncodedKeySpec priv_spec = new PKCS8EncodedKeySpec(
privKeyInByte);
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
PrivateKey privKey = mykeyFactory.generatePrivate(priv_spec);
Cipher cipher = Cipher.getInstance(mykeyFactory.getAlgorithm());
cipher.init(Cipher.ENCRYPT_MODE, privKey);
return cipher.doFinal(data);
} catch (Exception e) {
return null;
}
}
/**
* 用RSA公鑰解密
*
* @param pubKeyInByte 公鑰打包成byte[]形式
* @param data 要解密的資料
* @return 解密資料
*/
public static byte[] decryptByRSA1(byte[] pubKeyInByte, byte[] data) {
try {
KeyFactory mykeyFactory = KeyFactory.getInstance("RSA");
X509EncodedKeySpec pub_spec = new X509EncodedKeySpec(pubKeyInByte);
PublicKey pubKey = mykeyFactory.generatePublic(pub_spec);
Cipher cipher = Cipher.getInstance(mykeyFactory.getAlgorithm());
cipher.init(Cipher.DECRYPT_MODE, pubKey);
return cipher.doFinal(data);
} catch (Exception e) {
return null;
}
}
/**
* 計算字元串的SHA數字摘要，以byte[]形式傳回
*/
public static byte[] MdigestSHA(String source) {
//byte[] nullreturn = { 0 };
try {
MessageDigest thisMD = MessageDigest.getInstance("SHA");
byte[] digest = thisMD.digest(source.getBytes("UTF-8"));
return digest;
} catch (Exception e) {
return null;
}
}
/**
* 測試
*/
public static void main(String[] args) {
try {
//私鑰加密 公鑰解密
//生成私鑰-公鑰對
Object[] v = giveRSAKeyPairInByte();
//獲得摘要
byte[] source = MdigestSHA("假設這是要加密的客戶資料");
//使用私鑰對摘要進行加密 獲得密文 即數字簽名
byte[] sign = sign((byte[]) v[0], source);
//使用公鑰對密文進行解密,解密後與摘要進行比對
boolean yes = verify((byte[]) v[1], source, sign);
if (yes) {
System.out.println("比對成功 合法的簽名!");
}
//公鑰加密私鑰解密
//獲得摘要
byte[] sourcepub_pri = ("13265986584||316494646546486498||01||public").getBytes("UTF-8");
//使用公鑰對摘要進行加密 獲得密文
byte[] signpub_pri = encryptByRSA((byte[]) v[1], sourcepub_pri);
//System.out.println("公鑰加密密文："+new String(Base64.encodeBase64(signpub_pri)));
//使用私鑰對密文進行解密 傳回解密後的資料
byte[] newSourcepub_pri = decryptByRSA((byte[]) v[0], signpub_pri);
System.out.println("私鑰解密：" + new String(newSourcepub_pri, "UTF-8"));
//對比源資料與解密後的資料
if (Arrays.equals(sourcepub_pri, newSourcepub_pri)) {
System.out.println("比對成功 合法的私鑰!");
}
//私鑰加密公鑰解密
//獲得摘要
//byte[] sourcepri_pub = MdigestSHA("假設這是要加密的客戶資料");
byte[] sourcepri_pub = ("13265986584||316494646546486498||01||private").getBytes("UTF-8");
//使用私鑰對摘要進行加密 獲得密文
byte[] signpri_pub = encryptByRSA1((byte[]) v[0], sourcepri_pub);
// System.out.println("私鑰加密密文："+new String(Base64.encodeBase64(sign11)));
//使用公鑰對密文進行解密 傳回解密後的資料
byte[] newSourcepri_pub = decryptByRSA1((byte[]) v[1], signpri_pub);
System.out.println("公鑰解密：" + new String(newSourcepri_pub, "UTF-8"));
String PUBLICKEY = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCEGENnf3rdiO20isoLQqezw12FoWXII9FBw8nR1MWQ3X0CVzOsqY1hOmxD/YI9OB7WVIaVax5tj1l+wk6A0v85Z4OpGWqz4B5L3fCUlBwf/M6DXHlSN1OZttvQF3OeWvc6gvJHihR7pp18zc4KfCJx0Ry6IrGH/2SNOVE1AIgvRQIDAQAB";
String PRIVATEKEY = "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";
byte[] signPrivate = Base64.decodeBase64(PRIVATEKEY.getBytes());
byte[] signPublic = Base64.decodeBase64(PUBLICKEY.getBytes());
String publicpwd = "N/b4nYbbLFVq0yTAIOpNNydtNQUCQxQy0B7bD6kzxLMW2guYxXtWOC/9Z5dpWecx/y7d5CezUJ6cf/8++msiNie4DcKBaFDFPh5rPbjeEB+DRfhjcdR2BsVGXWLsq3dLYLgZObQXG6Tb9rXakuH34Y+6KIIwCjiODH2QAU+PSiM=";
String privatepwd = "MTMyNjU5ODY1ODR8fDMxNjQ5NDY0NjU0NjQ4NjQ5OHx8MDF8fHByaXZhdGU=";
//使用私鑰對密文進行解密 傳回解密後的資料
byte[] newSource111 = decryptByRSA(signPrivate, Base64.decodeBase64(publicpwd.getBytes()));
System.out.println("私鑰解密1：" + new String(newSource111, "UTF-8"));
} catch (Exception e) {
e.printStackTrace();
}
/*運作結果：
比對成功 合法的簽名!
私鑰解密：13265986584||316494646546486498||01||public
比對成功 合法的私鑰!
公鑰解密：13265986584||316494646546486498||01||private
私鑰解密1：13265986584||316494646546486498||01||3156464564*/
}
}
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