Java实现RSA签名以及验签代码示例
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2022-07-10 21:28:39
项目介绍最近需要实现对接口的签名和加密，特此整理一下，方便以后查看。使用的是RSA非对称加密，签名方法用的是RSA自带的。签名原理，私钥签名，公钥验签需要三个工具类：BASE64.java RSAEncrypt.java RSASignature.java流程图如下(无证书情况) 如果第三方不想让接口提供方知道他们的私钥，可以让第三方自己生成公私钥，把公钥公开出来 验签得双方验证才行，就是说双方都得有自己的公私钥，传输过程带上自己的公钥去验证，但是这有个问题，这个公私钥...
项目介绍
最近需要实现对接口的签名和加密，特此整理一下，方便以后查看。
使用的是RSA非对称加密，签名方法用的是RSA自带的。
签名原理，私钥签名，公钥验签
需要三个工具类：BASE64.java RSAEncrypt.java RSASignature.java
流程图如下(无证书情况) 如果第三方不想让接口提供方知道他们的私钥，可以让第三方自己生成公私钥，把公钥公开出来 验签得双方验证才行，就是说双方都得有自己的公私钥，传输过程带上自己的公钥去验证，但是这有个问题，这个公私钥的合法性，如果是用证书可以用证书链的验证解决
***
签名生成通用规则
签名原文组装说明：
无论是请求还是响应，签名原文组装规则如下：
1)除sign字段外，所有参数按照字段名的ASCII字码从小到大排序。排序完成之后，再把所有键值对以“&”字符连接起来(如key1=value1&key2=value2)。
2)如果参数值是一个子JSONObject，则先将子JSON按照字段名的ASCII字码从小到大排序，把子JSON中的所有键值对以“&”字符连接起来，以此作为该参数的值，再进行拼接。
3)如果参数值是一个JSON数组，需要把JSON数组里面的内容转换成字符串，然后按照字段名的ASCII字码从小到大排序，把子JSON中的所有键值对以“&”字符连接起来，以此作为该参数的值，再进行拼接。
4)所有参数是指实际出现的所有非空参数，即使是没有事先描述的非空字段，也需要参与签名组串。
5)签名原始串中，各字段和字段值都采用原始值，不进行URLEncoder。
6)参数名区分大小写。
签名(sign)生成通用步骤：
对上述拼接好的data_to_sign使用商户的私钥进行RSA签名
示例如下：
假设传递的json串如下：
{"area":"郑州",
"email":"1234567@qq.com",
"frimname":"张三",
"idNumber":"320206198611222555",
"name":"赵六",
"phone":"17839949863"}
1、拼接的待签原文(data_to_sign)：
email=1234567@qq.com&frimname=张三&idNumber=320206198611222555&name=赵六&phone=17839949869
2、使用线下拿到的私钥进行签名,sign=sign(data_to_sign,私钥));
3、执行成功后，会得到一个sign，是由接口返回的签名，再用data_to_sign和
服务商的公钥验证签名，保证数据没被篡改。
BASE64
import org.apache.tomcat.util.codec.binary.Base64;
import sun.misc.BASE64Encoder;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
public 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) '/';
}
/**
* 将本地图片进行Base64位编码
*
* @param imgUrl 图片的url路径，如D:\\photo\\1.png
*
* @return
*/
public static String encodeImgageToBase64(File imageFile) {
// 将图片文件转化为字节数组字符串，并对其进行Base64编码处理
// 其进行Base64编码处理
byte[] data = null;
// 读取图片字节数组
try {
InputStream in = new FileInputStream(imageFile);
data = new byte[in.available()];
in.read(data);
in.close();
} catch (Exception e) {
e.printStackTrace();
}
// 对字节数组Base64编码
BASE64Encoder encoder = new BASE64Encoder();
// 返回Base64编码过的字节数组字符串
return encoder.encode(data);
}
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;
}
/**
*
* 功能描述：Base64加密（将byte[]转换成字符串） 方法。
* <P/>
* 创建时间：2017-02-14
* <P/>
* 创建人： 董耀明
*
* @param data byte[]类型 要加密的数据
*
* @return String类型 加密后结果
*
*/
public static String encryptBASE64(byte[] data)
{
return Base64.encodeBase64String(data);
//return (new BASE64Encoder()).encodeBuffer(data);
}
/**
*
* 功能描述：Base64加密（将byte[]转换成字符串） 方法。
* <P/>
* 创建时间：2017-02-14
* <P/>
* 创建人： 董耀明
*
* @param data String类型 要加密的数据
*
* @return String类型 加密后结果
*
*/
public static String encryptBASE64(String data)
{
try {
//return (new BASE64Encoder()).encodeBuffer(data.getBytes("UTF-8"));
return Base64.encodeBase64String(data.getBytes("UTF-8"));
} catch (Exception e) {
return null;
}
}
/**
*
* 功能描述：Base64加密（将byte[]转换成字符串） 方法。
* <P/>
* 创建时间：2017-02-14
* <P/>
* 创建人： 董耀明
*
* @param data String类型 要加密的数据
*
* @param encode String类型 编码类型
*
* @return String类型 加密后结果
*
*/
public static String encryptBASE64(String data,String encode)
{
try
{
if (encode == null || "".equals(encode))
{
return Base64.encodeBase64String(data.getBytes());
} else
{
return Base64.encodeBase64String(data.getBytes(encode));
}
} catch (UnsupportedEncodingException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
}
}
RSAEncrypt
因为业务需求，我把自己用的公私钥分别命名为 publicKey.keystore 和 privateKey.keystore 保存在了FTP服务器里，
读取也是从FTP服务器读。(接口提供方只需要生成一次公私钥，把公钥给第三方，用于加密)
/**
* @author: zph
* @Date: 2020/7/10 15:28
* @Description: RSA加密解密工具类
*/
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' };
// FTP服务器hostname
public static String HOST = "";
// FTP服务器端口
public static Integer PORT = ;
// FTP登录账号
public static String USERNAME = "";
// FTP登录密码
public static String PASSWORD = "";
// FTP上传路径
public static String INVOICE_BASE_PATH = "";
/**
* 随机生成密钥对
*/
public static void genKeyPair() {
// 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());
System.err.println(publicKeyString);
System.err.println(privateKeyString);
// 将公密钥对写入到文件
/*InputStream is = null;
InputStream is1 = null;
is = new ByteArrayInputStream(publicKeyString.getBytes());
is1 = new ByteArrayInputStream(privateKeyString.getBytes());
FTPClient ftpClient = new FTPClient();
ftpClient.connect(HOST);
ftpClient.login(USERNAME,PASSWORD);
ftpClient.changeWorkingDirectory(INVOICE_BASE_PATH);
ftpClient.setFileType(FTPClient.LOCAL_FILE_TYPE);
ftpClient.storeFile(new String("publicKey.keystore".getBytes(),"iso-8859-1"),is);
ftpClient.storeFile(new String("privateKey.keystore".getBytes(),"iso-8859-1"),is1);
is.close();
is1.close();*/
//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
*
* @throws Exception
* 加载公钥时产生的异常
*/
public static String loadPublicKeyByFile() throws Exception {
try {
FTPClient ftpClient = new FTPClient();
ftpClient.connect(HOST);
ftpClient.login(USERNAME,PASSWORD);
ftpClient.changeWorkingDirectory(INVOICE_BASE_PATH);
InputStream is = ftpClient.retrieveFileStream("publicKey.keystore");
BufferedReader br = new BufferedReader(new InputStreamReader(is,"UTF-8"));
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
*
* @return 是否成功
* @throws Exception
*/
public static String loadPrivateKeyByFile() throws Exception {
try {
FTPClient ftpClient = new FTPClient();
ftpClient.connect(HOST);
ftpClient.login(USERNAME,PASSWORD);
ftpClient.changeWorkingDirectory(INVOICE_BASE_PATH);
InputStream is = ftpClient.retrieveFileStream("privateKey.keystore");
BufferedReader br = new BufferedReader(new InputStreamReader(is,"UTF-8"));
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();
}
}
RSASignature
import java.lang.reflect.Field;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Map;
/**
* @author: zph
* @Date: 2020/7/10 15:29
* @Description: 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;
}
/**
* 根据 content 和 私钥 生成签名
* @param content 按字典顺序排序的内容
* @param privateKey ftp上保存的私钥
* @return
*/
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;
}
/**
* 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
* @return 布尔值
*/
public static boolean doCheck(String content, String sign, String publicKey)
{
try
{
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
byte[] encodedKey = BASE64.decode(publicKey);
if (encodedKey==null){
return false;
}
PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));
// 用私钥对信息生成数字签名
java.security.Signature signature = java.security.Signature
.getInstance(SIGN_ALGORITHMS);
signature.initVerify(pubKey);
signature.update( content.getBytes() );
// 验证方法 返回true则为比对成功
boolean bverify = signature.verify( BASE64.decode(sign) );
return bverify;
}
catch (Exception e)
{
e.printStackTrace();
}
return false;
}
/**
* 对象转HashMap
* @param obj
* @return
*/
public static Map<String, Object> objectToMap(Object obj) {
if (obj == null) {
return null;
}
Map<String, Object> map = new HashMap<String, Object>();
try {
Field[] declaredFields = obj.getClass().getDeclaredFields();
for (Field field : declaredFields) {
field.setAccessible(true);
map.put(field.getName(), field.get(obj));
}
} catch (Exception e) {
}
return map;
}
/**
* @author: zph
* @Date: 2020/7/14 17:45
* @Description: 将签名的参数内容按参数名的字典顺序进行排序，并拼接为字符串
*/
public static String getContent(Map<String,Object> map){
//得到第三方签名 第三方会把sign也放在json里，故转map的时候需要把sign删除
map.remove("sign");
map.entrySet().removeIf(entry -> entry.getValue() == null);
// 将签名的参数内容按参数名的字典顺序进行排序，并拼接为字符串
StringBuilder sb = new StringBuilder();
map.entrySet().stream().sorted(Comparator.comparing(Map.Entry::getKey)).forEach(entry ->
sb.append(entry.getKey()).append("=").append(entry.getValue()).append("&")
);
return sb.toString().substring(0, sb.length() - 1);
}
/**
* 签名方法
* 因为很多处都需要用，特地封装一下，方便调用
* @param paramStr 按字典顺序拼接过的字符串
* @param publicKey 从数据库查询出来的第三方公钥
* @param sign 第三方签名
* @return
*/
public static boolean signVerify(String paramStr,String publicKey,String sign){
System.err.println(paramStr);
try {
//String privateSign = RSASignature.sign(paramStr, RSAEncrypt.loadPrivateKeyByFile());
// 使用公钥进行验签
boolean result = RSASignature.doCheck(paramStr, sign, publicKey);
if (result){
return true;
}
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
}
Main方法
public static void main(String[] args) {
try {
// 生成密钥对
KeyPair keyPair = getKeyPair();
String privateKey = new String(Base64.encodeBase64(keyPair.getPrivate().getEncoded()));
String publicKey = new String(Base64.encodeBase64(keyPair.getPublic().getEncoded()));
System.out.println("私钥:" + privateKey);
System.out.println("公钥:" + publicKey);
// RSA加密
String data = "待加密的文字内容";
String encryptData = encrypt(data, getPublicKey(publicKey));
System.out.println("加密后内容:" + encryptData);
// RSA解密
String decryptData = decrypt(encryptData, getPrivateKey(privateKey));
System.out.println("解密后内容:" + decryptData);
// RSA签名
String sign = sign(data, getPrivateKey(privateKey));
// RSA验签
boolean result = verify(data, getPublicKey(publicKey), sign);
System.out.print("验签结果:" + result);
} catch (Exception e) {
e.printStackTrace();
System.out.print("加解密异常");
}
}
本文地址：https://blog.csdn.net/qq_38799009/article/details/107359515