Java使用RSA加密解密签名及校验
概述
由于项目要用到非对称加密解密签名校验什么的，于是参考《Java加密解密的艺术》写一个RSA进行加密解密签名及校验的Demo，代码很简单，特此分享！
详细
代码下载：http://www.demodashi.com/demo/10269.html
由于项目要用到非对称加密解密签名校验什么的，于是参考《Java加密解密的艺术》写一个RSA进行加密解密签名及校验的Demo，代码很简单，特此分享！
一、项目截图
代码下载后，导入到eclipse中，如下：
运行MainTest类即可。
二、具体代码类
RSA加密解密类：
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package com.ihep;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
public class RSAEncrypt {
/**
* 字节数据转字符串专用集合
*/
private static final char``[] HEX_CHAR = { '0'``, '1'``, '2'``, '3'``, '4'``, '5'``, '6'``,
'7'``, '8'``, '9'``, 'a'``, 'b'``, 'c'``, 'd'``, 'e'``, 'f' };
/**
* 随机生成密钥对
*/
public static void genKeyPair(String filePath) {
// KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
KeyPairGenerator keyPairGen = null``;
try {
keyPairGen = KeyPairGenerator.getInstance(``"RSA"``);
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// 初始化密钥对生成器，密钥大小为96-1024位
keyPairGen.initialize(``1024``,``new SecureRandom());
// 生成一个密钥对，保存在keyPair中
KeyPair keyPair = keyPairGen.generateKeyPair();
// 得到私钥
RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
// 得到公钥
RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
try {
// 得到公钥字符串
String publicKeyString = Base64.encode(publicKey.getEncoded());
// 得到私钥字符串
String privateKeyString = Base64.encode(privateKey.getEncoded());
// 将密钥对写入到文件
FileWriter pubfw = new FileWriter(filePath + "/publicKey.keystore"``);
FileWriter prifw = new FileWriter(filePath + "/privateKey.keystore"``);
BufferedWriter pubbw = new BufferedWriter(pubfw);
BufferedWriter pribw = new BufferedWriter(prifw);
pubbw.write(publicKeyString);
pribw.write(privateKeyString);
pubbw.flush();
pubbw.close();
pubfw.close();
pribw.flush();
pribw.close();
prifw.close();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 从文件中输入流中加载公钥
*
* @param in
* 公钥输入流
* @throws Exception
* 加载公钥时产生的异常
*/
public static String loadPublicKeyByFile(String path) throws Exception {
try {
BufferedReader br = new BufferedReader(``new FileReader(path
+ "/publicKey.keystore"``));
String readLine = null``;
StringBuilder sb = new StringBuilder();
while ((readLine = br.readLine()) != null``) {
sb.append(readLine);
}
br.close();
return sb.toString();
} catch (IOException e) {
throw new Exception(``"公钥数据流读取错误"``);
} catch (NullPointerException e) {
throw new Exception(``"公钥输入流为空"``);
}
}
/**
* 从字符串中加载公钥
*
* @param publicKeyStr
* 公钥数据字符串
* @throws Exception
* 加载公钥时产生的异常
*/
public static RSAPublicKey loadPublicKeyByStr(String publicKeyStr)
throws Exception {
try {
byte``[] buffer = Base64.decode(publicKeyStr);
KeyFactory keyFactory = KeyFactory.getInstance(``"RSA"``);
X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
return (RSAPublicKey) keyFactory.generatePublic(keySpec);
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此算法"``);
} catch (InvalidKeySpecException e) {
throw new Exception(``"公钥非法"``);
} catch (NullPointerException e) {
throw new Exception(``"公钥数据为空"``);
}
}
/**
* 从文件中加载私钥
*
* @param keyFileName
* 私钥文件名
* @return 是否成功
* @throws Exception
*/
public static String loadPrivateKeyByFile(String path) throws Exception {
try {
BufferedReader br = new BufferedReader(``new FileReader(path
+ "/privateKey.keystore"``));
String readLine = null``;
StringBuilder sb = new StringBuilder();
while ((readLine = br.readLine()) != null``) {
sb.append(readLine);
}
br.close();
return sb.toString();
} catch (IOException e) {
throw new Exception(``"私钥数据读取错误"``);
} catch (NullPointerException e) {
throw new Exception(``"私钥输入流为空"``);
}
}
public static RSAPrivateKey loadPrivateKeyByStr(String privateKeyStr)
throws Exception {
try {
byte``[] buffer = Base64.decode(privateKeyStr);
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
KeyFactory keyFactory = KeyFactory.getInstance(``"RSA"``);
return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此算法"``);
} catch (InvalidKeySpecException e) {
throw new Exception(``"私钥非法"``);
} catch (NullPointerException e) {
throw new Exception(``"私钥数据为空"``);
}
}
/**
* 公钥加密过程
*
* @param publicKey
* 公钥
* @param plainTextData
* 明文数据
* @return
* @throws Exception
* 加密过程中的异常信息
*/
public static byte``[] encrypt(RSAPublicKey publicKey, byte``[] plainTextData)
throws Exception {
if (publicKey == null``) {
throw new Exception(``"加密公钥为空, 请设置"``);
}
Cipher cipher = null``;
try {
// 使用默认RSA
cipher = Cipher.getInstance(``"RSA"``);
// cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte``[] output = cipher.doFinal(plainTextData);
return output;
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此加密算法"``);
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null``;
} catch (InvalidKeyException e) {
throw new Exception(``"加密公钥非法,请检查"``);
} catch (IllegalBlockSizeException e) {
throw new Exception(``"明文长度非法"``);
} catch (BadPaddingException e) {
throw new Exception(``"明文数据已损坏"``);
}
}
/**
* 私钥加密过程
*
* @param privateKey
* 私钥
* @param plainTextData
* 明文数据
* @return
* @throws Exception
* 加密过程中的异常信息
*/
public static byte``[] encrypt(RSAPrivateKey privateKey, byte``[] plainTextData)
throws Exception {
if (privateKey == null``) {
throw new Exception(``"加密私钥为空, 请设置"``);
}
Cipher cipher = null``;
try {
// 使用默认RSA
cipher = Cipher.getInstance(``"RSA"``);
cipher.init(Cipher.ENCRYPT_MODE, privateKey);
byte``[] output = cipher.doFinal(plainTextData);
return output;
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此加密算法"``);
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null``;
} catch (InvalidKeyException e) {
throw new Exception(``"加密私钥非法,请检查"``);
} catch (IllegalBlockSizeException e) {
throw new Exception(``"明文长度非法"``);
} catch (BadPaddingException e) {
throw new Exception(``"明文数据已损坏"``);
}
}
/**
* 私钥解密过程
*
* @param privateKey
* 私钥
* @param cipherData
* 密文数据
* @return 明文
* @throws Exception
* 解密过程中的异常信息
*/
public static byte``[] decrypt(RSAPrivateKey privateKey, byte``[] cipherData)
throws Exception {
if (privateKey == null``) {
throw new Exception(``"解密私钥为空, 请设置"``);
}
Cipher cipher = null``;
try {
// 使用默认RSA
cipher = Cipher.getInstance(``"RSA"``);
// cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
cipher.init(Cipher.DECRYPT_MODE, privateKey);
byte``[] output = cipher.doFinal(cipherData);
return output;
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此解密算法"``);
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null``;
} catch (InvalidKeyException e) {
throw new Exception(``"解密私钥非法,请检查"``);
} catch (IllegalBlockSizeException e) {
throw new Exception(``"密文长度非法"``);
} catch (BadPaddingException e) {
throw new Exception(``"密文数据已损坏"``);
}
}
/**
* 公钥解密过程
*
* @param publicKey
* 公钥
* @param cipherData
* 密文数据
* @return 明文
* @throws Exception
* 解密过程中的异常信息
*/
public static byte``[] decrypt(RSAPublicKey publicKey, byte``[] cipherData)
throws Exception {
if (publicKey == null``) {
throw new Exception(``"解密公钥为空, 请设置"``);
}
Cipher cipher = null``;
try {
// 使用默认RSA
cipher = Cipher.getInstance(``"RSA"``);
// cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
cipher.init(Cipher.DECRYPT_MODE, publicKey);
byte``[] output = cipher.doFinal(cipherData);
return output;
} catch (NoSuchAlgorithmException e) {
throw new Exception(``"无此解密算法"``);
} catch (NoSuchPaddingException e) {
e.printStackTrace();
return null``;
} catch (InvalidKeyException e) {
throw new Exception(``"解密公钥非法,请检查"``);
} catch (IllegalBlockSizeException e) {
throw new Exception(``"密文长度非法"``);
} catch (BadPaddingException e) {
throw new Exception(``"密文数据已损坏"``);
}
}
/**
* 字节数据转十六进制字符串
*
* @param data
* 输入数据
* @return 十六进制内容
*/
public static String byteArrayToString(``byte``[] data) {
StringBuilder stringBuilder = new StringBuilder();
for (``int i = 0``; i < data.length; i++) {
// 取出字节的高四位 作为索引得到相应的十六进制标识符 注意无符号右移
stringBuilder.append(HEX_CHAR[(data[i] & 0xf0``) >>> 4``]);
// 取出字节的低四位 作为索引得到相应的十六进制标识符
stringBuilder.append(HEX_CHAR[(data[i] & 0x0f``)]);
if (i < data.length - 1``) {
stringBuilder.append(``' '``);
}
}
return stringBuilder.toString();
}
}
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签名及校验类：
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package com.ihep;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
/**
* RSA签名验签类
*/
public class RSASignature{
/**
* 签名算法
*/
public static final String SIGN_ALGORITHMS = "SHA1WithRSA"``;
/**
* RSA签名
* @param content 待签名数据
* @param privateKey 商户私钥
* @param encode 字符集编码
* @return 签名值
*/
public static String sign(String content, String privateKey, String encode)
{
try
{
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec( Base64.decode(privateKey) );
KeyFactory keyf = KeyFactory.getInstance(``"RSA"``);
PrivateKey priKey = keyf.generatePrivate(priPKCS8);
java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
signature.initSign(priKey);
signature.update( content.getBytes(encode));
byte``[] signed = signature.sign();
return Base64.encode(signed);
}
catch (Exception e)
{
e.printStackTrace();
}
return null``;
}
public static String sign(String content, String privateKey)
{
try
{
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec( Base64.decode(privateKey) );
KeyFactory keyf = KeyFactory.getInstance(``"RSA"``);
PrivateKey priKey = keyf.generatePrivate(priPKCS8);
java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
signature.initSign(priKey);
signature.update( content.getBytes());
byte``[] signed = signature.sign();
return Base64.encode(signed);
}
catch (Exception e)
{
e.printStackTrace();
}
return null``;
}
/**
* RSA验签名检查
* @param content 待签名数据
* @param sign 签名值
* @param publicKey 分配给开发商公钥
* @param encode 字符集编码
* @return 布尔值
*/
public static boolean doCheck(String content, String sign, String publicKey,String encode)
{
try
{
KeyFactory keyFactory = KeyFactory.getInstance(``"RSA"``);
byte``[] encodedKey = Base64.decode(publicKey);
PublicKey pubKey = keyFactory.generatePublic(``new X509EncodedKeySpec(encodedKey));
java.security.Signature signature = java.security.Signature
.getInstance(SIGN_ALGORITHMS);
signature.initVerify(pubKey);
signature.update( content.getBytes(encode) );
boolean bverify = signature.verify( Base64.decode(sign) );
return bverify;
}
catch (Exception e)
{
e.printStackTrace();
}
return false``;
}
public static boolean doCheck(String content, String sign, String publicKey)
{
try
{
KeyFactory keyFactory = KeyFactory.getInstance(``"RSA"``);
byte``[] encodedKey = Base64.decode(publicKey);
PublicKey pubKey = keyFactory.generatePublic(``new X509EncodedKeySpec(encodedKey));
java.security.Signature signature = java.security.Signature
.getInstance(SIGN_ALGORITHMS);
signature.initVerify(pubKey);
signature.update( content.getBytes() );
boolean bverify = signature.verify( Base64.decode(sign) );
return bverify;
}
catch (Exception e)
{
e.printStackTrace();
}
return false``;
}
}
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再来一个Base64的类，当然你也可以用commons-codec-1.9.jar
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package com.ihep;
public final class Base64 {
static private final int BASELENGTH = 128``;
static private final int LOOKUPLENGTH = 64``;
static private final int TWENTYFOURBITGROUP = 24``;
static private final int EIGHTBIT = 8``;
static private final int SIXTEENBIT = 16``;
static private final int FOURBYTE = 4``;
static private final int SIGN = -``128``;
static private final char PAD = '='``;
static private final boolean fDebug = false``;
static final private byte``[] base64Alphabet = new byte``[BASELENGTH];
static final private char``[] lookUpBase64Alphabet = new char``[LOOKUPLENGTH];
static {
for (``int i = 0``; i < BASELENGTH; ++i) {
base64Alphabet[i] = -``1``;
}
for (``int i = 'Z'``; i >= 'A'``; i--) {
base64Alphabet[i] = (``byte``) (i - 'A'``);
}
for (``int i = 'z'``; i >= 'a'``; i--) {
base64Alphabet[i] = (``byte``) (i - 'a' + 26``);
}
for (``int i = '9'``; i >= '0'``; i--) {
base64Alphabet[i] = (``byte``) (i - '0' + 52``);
}
base64Alphabet[``'+'``] = 62``;
base64Alphabet[``'/'``] = 63``;
for (``int i = 0``; i <= 25``; i++) {
lookUpBase64Alphabet[i] = (``char``) (``'A' + i);
}
for (``int i = 26``, j = 0``; i <= 51``; i++, j++) {
lookUpBase64Alphabet[i] = (``char``) (``'a' + j);
}
for (``int i = 52``, j = 0``; i <= 61``; i++, j++) {
lookUpBase64Alphabet[i] = (``char``) (``'0' + j);
}
lookUpBase64Alphabet[``62``] = (``char``) '+'``;
lookUpBase64Alphabet[``63``] = (``char``) '/'``;
}
private static boolean isWhiteSpace(``char octect) {
return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9``);
}
private static boolean isPad(``char octect) {
return (octect == PAD);
}
private static boolean isData(``char octect) {
return (octect < BASELENGTH && base64Alphabet[octect] != -``1``);
}
/**
* Encodes hex octects into Base64
*
* @param binaryData Array containing binaryData
* @return Encoded Base64 array
*/
public static String encode(``byte``[] binaryData) {
if (binaryData == null``) {
return null``;
}
int lengthDataBits = binaryData.length * EIGHTBIT;
if (lengthDataBits == 0``) {
return ""``;
}
int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1 : numberTriplets;
char encodedData[] = null``;
encodedData = new char``[numberQuartet * 4``];
byte k = 0``, l = 0``, b1 = 0``, b2 = 0``, b3 = 0``;
int encodedIndex = 0``;
int dataIndex = 0``;
if (fDebug) {
System.out.println(``"number of triplets = " + numberTriplets);
}
for (``int i = 0``; i < numberTriplets; i++) {
b1 = binaryData[dataIndex++];
b2 = binaryData[dataIndex++];
b3 = binaryData[dataIndex++];
if (fDebug) {
System.out.println(``"b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);
}
l = (``byte``) (b2 & 0x0f``);
k = (``byte``) (b1 & 0x03``);
byte val1 = ((b1 & SIGN) == 0``) ? (``byte``) (b1 >> 2``) : (``byte``) ((b1) >> 2 ^ 0xc0``);
byte val2 = ((b2 & SIGN) == 0``) ? (``byte``) (b2 >> 4``) : (``byte``) ((b2) >> 4 ^ 0xf0``);
byte val3 = ((b3 & SIGN) == 0``) ? (``byte``) (b3 >> 6``) : (``byte``) ((b3) >> 6 ^ 0xfc``);
if (fDebug) {
System.out.println(``"val2 = " + val2);
System.out.println(``"k4 = " + (k << 4``));
System.out.println(``"vak = " + (val2 | (k << 4``)));
}
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4``)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2``) | val3];
encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f``];
}
// form integral number of 6-bit groups
if (fewerThan24bits == EIGHTBIT) {
b1 = binaryData[dataIndex];
k = (``byte``) (b1 & 0x03``);
if (fDebug) {
System.out.println(``"b1=" + b1);
System.out.println(``"b1<<2 = " + (b1 >> 2``));
}
byte val1 = ((b1 & SIGN) == 0``) ? (``byte``) (b1 >> 2``) : (``byte``) ((b1) >> 2 ^ 0xc0``);
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4``];
encodedData[encodedIndex++] = PAD;
encodedData[encodedIndex++] = PAD;
} else if (fewerThan24bits == SIXTEENBIT) {
b1 = binaryData[dataIndex];
b2 = binaryData[dataIndex + 1``];
l = (``byte``) (b2 & 0x0f``);
k = (``byte``) (b1 & 0x03``);
byte val1 = ((b1 & SIGN) == 0``) ? (``byte``) (b1 >> 2``) : (``byte``) ((b1) >> 2 ^ 0xc0``);
byte val2 = ((b2 & SIGN) == 0``) ? (``byte``) (b2 >> 4``) : (``byte``) ((b2) >> 4 ^ 0xf0``);
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4``)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2``];
encodedData[encodedIndex++] = PAD;
}
return new String(encodedData);
}
/**
* Decodes Base64 data into octects
*
* @param encoded string containing Base64 data
* @return Array containind decoded data.
*/
public static byte``[] decode(String encoded) {
if (encoded == null``) {
return null``;
}
char``[] base64Data = encoded.toCharArray();
// remove white spaces
int len = removeWhiteSpace(base64Data);
if (len % FOURBYTE != 0``) {
return null``;``//should be divisible by four
}
int numberQuadruple = (len / FOURBYTE);
if (numberQuadruple == 0``) {
return new byte``[``0``];
}
byte decodedData[] = null``;
byte b1 = 0``, b2 = 0``, b3 = 0``, b4 = 0``;
char d1 = 0``, d2 = 0``, d3 = 0``, d4 = 0``;
int i = 0``;
int encodedIndex = 0``;
int dataIndex = 0``;
decodedData = new byte``[(numberQuadruple) * 3``];
for (; i < numberQuadruple - 1``; i++) {
if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))
|| !isData((d3 = base64Data[dataIndex++]))
|| !isData((d4 = base64Data[dataIndex++]))) {
return null``;
}``//if found "no data" just return null
b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];
decodedData[encodedIndex++] = (``byte``) (b1 << 2 | b2 >> 4``);
decodedData[encodedIndex++] = (``byte``) (((b2 & 0xf``) << 4``) | ((b3 >> 2``) & 0xf``));
decodedData[encodedIndex++] = (``byte``) (b3 << 6 | b4);
}
if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))) {
return null``;``//if found "no data" just return null
}
b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];
d3 = base64Data[dataIndex++];
d4 = base64Data[dataIndex++];
if (!isData((d3)) || !isData((d4))) {``//Check if they are PAD characters
if (isPad(d3) && isPad(d4)) {
if ((b2 & 0xf``) != 0``)``//last 4 bits should be zero
{
return null``;
}
byte``[] tmp = new byte``[i * 3 + 1``];
System.arraycopy(decodedData, 0``, tmp, 0``, i * 3``);
tmp[encodedIndex] = (``byte``) (b1 << 2 | b2 >> 4``);
return tmp;
} else if (!isPad(d3) && isPad(d4)) {
b3 = base64Alphabet[d3];
if ((b3 & 0x3``) != 0``)``//last 2 bits should be zero
{
return null``;
}
byte``[] tmp = new byte``[i * 3 + 2``];
System.arraycopy(decodedData, 0``, tmp, 0``, i * 3``);
tmp[encodedIndex++] = (``byte``) (b1 << 2 | b2 >> 4``);
tmp[encodedIndex] = (``byte``) (((b2 & 0xf``) << 4``) | ((b3 >> 2``) & 0xf``));
return tmp;
} else {
return null``;
}
} else { //No PAD e.g 3cQl
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];
decodedData[encodedIndex++] = (``byte``) (b1 << 2 | b2 >> 4``);
decodedData[encodedIndex++] = (``byte``) (((b2 & 0xf``) << 4``) | ((b3 >> 2``) & 0xf``));
decodedData[encodedIndex++] = (``byte``) (b3 << 6 | b4);
}
return decodedData;
}
/**
* remove WhiteSpace from MIME containing encoded Base64 data.
*
* @param data the byte array of base64 data (with WS)
* @return the new length
*/
private static int removeWhiteSpace(``char``[] data) {
if (data == null``) {
return 0``;
}
// count characters that's not whitespace
int newSize = 0``;
int len = data.length;
for (``int i = 0``; i < len; i++) {
if (!isWhiteSpace(data[i])) {
data[newSize++] = data[i];
}
}
return newSize;
}
}
|
最后是一个MainTest：
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package com.ihep;
public class MainTest {
public static void main(String[] args) throws Exception {
String filepath=``"E:/tmp/"``;
//生成公钥和私钥文件
RSAEncrypt.genKeyPair(filepath);
System.out.println(``"--------------公钥加密私钥解密过程-------------------"``);
String plainText=``"ihep_公钥加密私钥解密"``;
//公钥加密过程
byte``[] cipherData=RSAEncrypt.encrypt(RSAEncrypt.loadPublicKeyByStr(RSAEncrypt.loadPublicKeyByFile(filepath)),plainText.getBytes());
String cipher=Base64.encode(cipherData);
//私钥解密过程
byte``[] res=RSAEncrypt.decrypt(RSAEncrypt.loadPrivateKeyByStr(RSAEncrypt.loadPrivateKeyByFile(filepath)), Base64.decode(cipher));
String restr=``new String(res);
System.out.println(``"原文："``+plainText);
System.out.println(``"加密："``+cipher);
System.out.println(``"解密："``+restr);
System.out.println();
System.out.println(``"--------------私钥加密公钥解密过程-------------------"``);
plainText=``"ihep_私钥加密公钥解密"``;
//私钥加密过程
cipherData=RSAEncrypt.encrypt(RSAEncrypt.loadPrivateKeyByStr(RSAEncrypt.loadPrivateKeyByFile(filepath)),plainText.getBytes());
cipher=Base64.encode(cipherData);
//公钥解密过程
res=RSAEncrypt.decrypt(RSAEncrypt.loadPublicKeyByStr(RSAEncrypt.loadPublicKeyByFile(filepath)), Base64.decode(cipher));
restr=``new String(res);
System.out.println(``"原文："``+plainText);
System.out.println(``"加密："``+cipher);
System.out.println(``"解密："``+restr);
System.out.println();
System.out.println(``"---------------私钥签名过程------------------"``);
String content=``"ihep_这是用于签名的原始数据"``;
String signstr=RSASignature.sign(content,RSAEncrypt.loadPrivateKeyByFile(filepath));
System.out.println(``"签名原串："``+content);
System.out.println(``"签名串："``+signstr);
System.out.println();
System.out.println(``"---------------公钥校验签名------------------"``);
System.out.println(``"签名原串："``+content);
System.out.println(``"签名串："``+signstr);
System.out.println(``"验签结果："``+RSASignature.doCheck(content, signstr, RSAEncrypt.loadPublicKeyByFile(filepath)));
System.out.println();
}
}
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