import java.io.File;
import java.math.BigInteger;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.security.MessageDigest;
import java.security.SecureRandom;
import java.util.List;

/**
 * @ClassName: SchnorrSignature
 * @date: 2020年6月16日 下午9:25:09
 * @Description:schnorr簽名
 */
public class SchnorrSignature {
 // 路徑前綴
 private static final String PERFIX_PATH = GetProjectPath.getPath() + "/ra/";
 // 存放公共參數(shù)
 private static final String PARAM_PATH = PERFIX_PATH + "initParams.properties";
 // 存放公鑰的路徑
 private static final String PUBLIC_KEY_PATH = PERFIX_PATH + "publicKey.properties";
 
 /**
 * @Description: 系統(tǒng)初始化階段，把初始化的密碼公共參數(shù)存放到文件中去
 * @param blq:選擇的q的bit長度
* @Date:下午9:28:20
 */
 public static void initPara(int blq) {
 File file = new File(PARAM_PATH);
 if(file.exists()) {
 System.out.println("已經(jīng)存在初始化參數(shù)，為不影響已經(jīng)頒發(fā)的證書，如果你強制要重新產(chǎn)生參數(shù)，請備份所有文件到其他路徑下，并重新生產(chǎn)密鑰對并重新簽名");
 }else {
 System.out.println("系統(tǒng)初始化中，生產(chǎn)公共參數(shù)... ...");
 BigInteger one = new BigInteger("1");
 BigInteger two = new BigInteger("2");
 BigInteger q, qp, p, a, g;
 int certainty = 100;
 SecureRandom sr = new SecureRandom();
 // blq長度的q， q是p-1的素因子 
 //生成BigInteger偽隨機數(shù)，它可能是（概率不小于1 - 1/2certainty）一個具有指定 bitLength 的素數(shù)
 q = new BigInteger(blq, certainty, sr);
 qp = BigInteger.ONE;
 do { // 選擇一個素數(shù) p 
 p = q.multiply(qp).multiply(two).add(one);
 if(p.isProbablePrime(certainty))
 break;
 qp = qp.add(BigInteger.ONE);
 } while(true);
 
 while(true) {
 a = (two.add(new BigInteger(blq, 100, sr))).mod(p);// (2+x) mod p
 BigInteger ga = (p.subtract(BigInteger.ONE)).divide(q);// (p-1)/q
 g = a.modPow(ga, p); // a^ga mod p = 1 
 if(g.compareTo(BigInteger.ONE) != 0) // g!=1
 break;
 }
 // 存放公共參數(shù)
 List<String> transArryToLi = KeyPairOperate.transArryToLi(new String[] {"blq=" + blq,"q=" + q, "p=" + p, "g=" + g});
 KeyPairOperate.writePublicKeyToFile(PARAM_PATH, transArryToLi, false);
 System.out.println("...");
 System.out.println("初始化完成！");
 }
 }
 
 /**
 * @Description: 為用戶生成公私鑰對
 * @param user：傳入用戶的身份
 * @Return:void
 * @Date:上午9:32:18
 */
 public static void generateKeyForUser(String user) {
 File file = new File(PERFIX_PATH + user + ".properties");
 if(file.exists()) {
 System.out.println(user + "已經(jīng)頒發(fā)了密鑰，請備份所有文件到其他路徑下，并重新簽名");
 }else {
 System.out.println("密鑰頒發(fā)中，請稍后");
 System.out.println("... ...");
 BigInteger sk,pk;// 私鑰和公鑰
 int blq = Integer.parseInt(KeyPairOperate.getDataFromFile(PARAM_PATH, "blq"));
 SecureRandom sr = new SecureRandom();
 // 隨機數(shù)作為私鑰
 sk = new BigInteger(blq, sr);
 
 // 私鑰的話名字命名
 List<String> toLiSK = KeyPairOperate.transArryToLi(new String[] {"sk=" + sk});
 KeyPairOperate.writePublicKeyToFile(PERFIX_PATH + user + ".properties", toLiSK, false);
 
 BigInteger g = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "g"));
 BigInteger p = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "p"));
 // 公鑰
 pk = g.modPow(sk, p);// g^w mod p -- 注意這兒是正，所以下面驗證的時候是用的負
 List<String> toLiPK = KeyPairOperate.transArryToLi(new String[] {user + "=" + pk});
 KeyPairOperate.writePublicKeyToFile(PUBLIC_KEY_PATH, toLiPK, true);
 System.out.println(user + " 密鑰頒發(fā)完成");
 }
 }
 
 /**
 * @Description: 產(chǎn)生簽名
 * @param sourcefilePath ： 待簽名文件路徑
 * @param user：傳入用戶的身份
 * @Date:下午10:41:37
 */
 public static void makeSign(String sourcefilePath, String user) {
 System.out.println(user+ "的文件" + KeyPairOperate.getFileName(sourcefilePath) + " 簽名開始");
 System.out.println("... ...");
 BigInteger q = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "q")); // 素數(shù) q
 BigInteger p = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "p")); // 素數(shù) p
 BigInteger g = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "g")); // q的原根 a
 
 // 私鑰
 BigInteger sk = new BigInteger(KeyPairOperate.getDataFromFile(PERFIX_PATH + user + ".properties", "sk")); // 私鑰
 
 SecureRandom sr = new SecureRandom();
 BigInteger r, x, e, y; 
 r = new BigInteger(q.bitLength(), sr); // 隨機數(shù)
 x = g.modPow(r, p); // g^r mod p
 // e=H(M||x)
 try {
 MessageDigest md5 = MessageDigest.getInstance("MD5");
 md5.update(Files.readAllBytes(Paths.get(sourcefilePath)));
 md5.update(x.toString().getBytes());
 byte[] digest = md5.digest();
 // e 將BigInteger的符號大小表示法轉(zhuǎn)換成一個BigInteger值
 e = new BigInteger(1, digest); 
 // y s2 = r
 y = (r.subtract(sk.multiply(e))).mod(q);
 List<String> transArryToLi = KeyPairOperate.transArryToLi(new String[] {"e="+e,"y="+y});
 String fileName =PERFIX_PATH + user + "_sign_" + KeyPairOperate.getFileName(sourcefilePath) + ".properties";
 KeyPairOperate.writePublicKeyToFile(fileName, transArryToLi, false);
 System.out.println(user+ "的文件" + KeyPairOperate.getFileName(sourcefilePath) + "簽名成功 !");
 } catch (Exception e1) {
 e1.printStackTrace();
 }
 }
 
 /**
 * @Description: 驗證簽名
 * @param sourcePath : 原文件路徑
 * @param user：傳入用戶的身份
 * @Return:void
 * @Date:上午11:07:04
 */
 public static void checkSign(String sourcefilePath, String user) {
 System.out.println("驗證簽名");
 
 BigInteger p = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "p")); // 素數(shù) p
 BigInteger g = new BigInteger(KeyPairOperate.getDataFromFile(PARAM_PATH, "g")); // q的原根 a
 
 BigInteger pk = new BigInteger(KeyPairOperate.getDataFromFile(PUBLIC_KEY_PATH, user));// 公鑰
 
 String fileName =PERFIX_PATH + user + "_sign_" + KeyPairOperate.getFileName(sourcefilePath) + ".properties"; 
 
 BigInteger e = new BigInteger(KeyPairOperate.getDataFromFile(fileName, "e")); // e 簽名信息1： 產(chǎn)生的簽名信息
 BigInteger y = new BigInteger(KeyPairOperate.getDataFromFile(fileName, "y"));; // y 簽名信息2: 加密后的消息
 
 // 計算的 x'
 BigInteger x1 = g.modPow(y, p); // g^y mod p -- y
 BigInteger x2 = (pk.modPow(e, p)).mod(p); // pk^e mod p 
 BigInteger x = x1.multiply(x2).mod(p); // x1*x2 mod p = (g^y)*(pk^e)mod p
 
 try {
 MessageDigest md5 = MessageDigest.getInstance("MD5");
 md5.update(Files.readAllBytes(Paths.get(sourcefilePath)));
 md5.update(x.toString().getBytes());
 byte[] digest = md5.digest();
 BigInteger h = new BigInteger(1, digest);
 System.out.println("... ...");
 if(e.equals(h))
 System.out.println(user+ "的文件" + KeyPairOperate.getFileName(sourcefilePath) + "驗證通過 !");
 else
 System.out.println(user+ "的文件" + KeyPairOperate.getFileName(sourcefilePath) + "驗證失敗 !");
 } catch (Exception e1) {
 e1.printStackTrace();
 }
 }
}

import java.io.File;

/**
 * @ClassName: GetProjectPath
 * @date: 2020年6月16日 下午10:58:53
 * @Description: 獲取項目絕對路徑
 */
public class GetProjectPath {
 
 public static String getPath() {
 File directory = new File("");
 String courseFile = null;
 try {
 courseFile = directory.getCanonicalPath().replace("\\", "/");
 }catch (Exception e) {
 e.printStackTrace();
 }
 return courseFile;
 }

}

import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

/**
 * @ClassName: KeyPairOperate
 * @date: 2020年6月16日 下午9:53:11
 * @Description: 密鑰對的管理與存儲
 */
public class KeyPairOperate {
 
 public static String getFileName(String path) {
 int indexOf = path.lastIndexOf("\\")+1;
 int last = path.lastIndexOf(".");
 return path.substring(indexOf, last);
 }
 
 /**
 * @Description: 工具類，數(shù)組轉(zhuǎn)集合
 * @param para
 * @return
 * @Return:List<String>
 * @Date:上午10:24:33
 */
 public static List<String> transArryToLi(String[] para){
 List<String> li = new ArrayList<String>();
 for(int i=0; i<para.length; i++) {
 li.add(para[i]);
 }
 return li;
 }
 
 /**
 * @Description: 獲取配置文件參數(shù)
 * @param path : 文件路徑
 * @param para ： 獲取參數(shù)的key
 * @Date:上午9:46:26
 */
 public static String getDataFromFile(String path, String key) {
 String para = null;
 try {
 Properties pro = new Properties();
 pro.load(new FileInputStream(path));
 para = (String) pro.get(key);
 } catch (Exception e) {
 e.printStackTrace();
 }
 return para;
 }
 
 /**
 * @Description:寫公共密鑰到文件 -- 公鑰證書列表
 * @param path : 存儲的路徑
 * @param param ： 參數(shù)
 * @param flag ： 是否是追加存儲，公共參數(shù)不是追加，公鑰是追加； 追加： true， 覆蓋： flase
 * @Return:void
 * @Date:上午10:20:25
 */
 public static void writePublicKeyToFile(String path, List<String> param, Boolean flag) {
 try {
 PrintWriter printWriter = new PrintWriter(new FileWriter(path,flag));
 for(String element : param) {
 printWriter.println(element);
 }
 printWriter.close();
 } catch (Exception e) {
 e.printStackTrace();
 }
 }
}

import org.junit.Test;
public class Shtest {
 String pathFile ="C:\\Users\\89763\\Desktop\\www.rtf";
 
 @Test
 public void initPara() {
 SchnorrSignature.initPara(12);
 }
 @Test
 public void generateKeyForUser() {
 SchnorrSignature.generateKeyForUser("xiaoming");
 SchnorrSignature.generateKeyForUser("xiaowang");
 }
 @Test
 public void makeSign() {
 SchnorrSignature.makeSign(pathFile,"xiaoming");
 SchnorrSignature.makeSign(pathFile,"xiaowang");
 }
 @Test
 public void checkSign() {
 
 SchnorrSignature.checkSign( pathFile ,"xiaoming");
 SchnorrSignature.checkSign( pathFile ,"xiaowang");
 }

}