SHA256不断创建不同的盐值

Question

我编写了SHA256算法的简化版本，并尝试了一些输入。首先，它似乎可以正常工作（尽管输出与在线代码有所不同），但是当我尝试使用Input “ Admin”尝试时，它会输出相同的哈希，无论添加到输入中的盐字符串如何。出乎意料的是，如果输入为“ admi”，“ admin1”或“ admin1234”，它仍然会输出相同的哈希。我找不到其他有相同问题的输入。 这是代码：

package src.encrypt;

import java.time.Instant;
import java.util.ArrayList;
import java.util.Random;

public class Password {
  private String salt;
  private String hash;

  private String saltGen() {
    final String hex = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    Random rnd = new Random(Instant.now().toEpochMilli());
    char[] salt = new char[16];
    for (int i = 0; i < 16; i++) {
      int n = rnd.nextInt(hex.length());
      salt[i] = hex.charAt(n);
    }
    return String.valueOf(salt);
  }

  public Password() {
  };

  public Password(String pass) {
    salt = saltGen();
    String p = new String(pass + salt);
    hash = sha256(p);
  }

  public String getSalt() {
    return salt;
  }

  public String getHash() {
    return hash;
  }

  public boolean compareHash(String h) {
    return getHash().equals(sha256(h + getSalt()));
  }

  // SHA-256 Hashing Algorithm
  public String sha256(String str) {

    // Pre-processing
    ArrayList<String> hash = new ArrayList<>();
    byte[] bytes = str.getBytes();
    int i = 0;
    for (i = 0; i < bytes.length - 4; i += 4) {
      String tmp = String.format("%8s", Integer.toBinaryString(bytes[i] & 0xff)).replace(' ', '0')
          + String.format("%8s", Integer.toBinaryString(bytes[i + 1] & 0xff)).replace(' ', '0') +
          String.format("%8s", Integer.toBinaryString(bytes[i + 2] & 0xff)).replace(' ', '0') +
          String.format("%8s", Integer.toBinaryString(bytes[i + 3] & 0xff)).replace(' ', '0');
      hash.add(tmp);
    }
    String temp = new String();
    for (int j = i; j < bytes.length; j++)
      temp = new String(temp + String.format("%8s", Integer.toBinaryString(bytes[j] & 0xff)).replace(' ', '0'));
    if (temp.length() < 32)
      temp = new String(temp + "10000000");
    while (temp.length() < 32)
      temp = new String(temp + "00000000");
    hash.add(temp);
    int l = 14 - hash.size() % 16;
    for (i = 0; i < l; i++)
      hash.add(new String("00000000000000000000000000000000"));
    String tmp = String.format("%64s", Long.toBinaryString((long) (bytes.length * 8))).replace(' ', '0');
    hash.add(tmp.substring(0, 32));
    hash.add(tmp.substring(32));

    // Init Hash values
    int H[] = {
        0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
    };

    // Init Round Constants
    int K[] = {
        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
    };

    // Create Message Schedule and Compressing
    l = hash.size() / 16;
    int a = H[0], b = H[1], c = H[2], d = H[3], e = H[4], f = H[5], g = H[6], h = H[7];
    ArrayList<Integer> w = new ArrayList<>();
    for (i = 0; i < l; i++) {
      for (int j = i * 16; j < (i + 1) * 16; j++) {
        w.add(Integer.parseInt(hash.get(j), 2));
      }
      for (int j = 16; j < 64; j++) {
        int s0 = rightRotate1(w.get(j - 15));
        int s1 = rightRotate2(w.get(j - 15));
        w.add(w.get(j - 16) + s0 + w.get(j - 7) + s1);
      }
      for (int j = 0; j < 64; j++) {
        int temp1 = h + rightRotate3(e) + ((e & f) ^ (~e & g)) + K[i] + w.get(i);
        int temp2 = rightRotate4(a) + ((a & b) ^ (a & c) ^ (b & c));
        h = g;
        g = f;
        f = e;
        e = d + temp1;
        d = c;
        c = b;
        b = a;
        a = temp1 + temp2;
      }
      // Modify final values
      H[0] = H[0] + a;
      H[1] = H[1] + b;
      H[2] = H[2] + c;
      H[3] = H[3] + d;
      H[4] = H[4] + e;
      H[5] = H[5] + f;
      H[6] = H[6] + g;
      H[7] = H[7] + h;
    }
    // Concatenate final hash
    String s = new String();
    for (i = 0; i < 8; i++) {
      s = new String(s + String.format("%08X", H[i]).toLowerCase());
    }
    return s;
  };
  // right rotate
  private int rotr(int x, int n) {
    return (x >>> n) | (x << (32 - n));
  }

  private int rightRotate3(int x) {
    return rotr(x, 6) ^ rotr(x, 11) ^ rotr(x, 25);
  }

  private int rightRotate4(int x) {
    return rotr(x, 2) ^ rotr(x, 13) ^ rotr(x, 22);
  }

  private int rightRotate1(int x) {
    return rotr(x, 7) ^ rotr(x, 18) ^ x >>> 3;
  }

  private int rightRotate2(int x) {
    return rotr(x, 17) ^ rotr(x, 19) ^ x >>> 10;
  }

使用输入“ admin”，输出始终为“ 0920B401857E70A28C7B645C04195F2F2F2F15B54B98A7E78A7E7810F6D46D46D46C3A9C79C74ADF6A” 谁能发现我犯的一些错误或错误？
请注意，我是Java的新手，所以我使用的某些方法可能不效率。

编辑 这是我称呼该方法的方式：

// Main.java
import src.encrypt.Password;

public class Main {
  public static void main(String[] args) {
    String pass = "admin";
    Password p = new Password(pass);
    System.out.println(p.getSalt()); // different calls, different values
    System.out.println(p.getHash()); // different calls, same value
  }
}

Answer 1

错误发生在消息时间表数组的处理中（w arrayList，术语来自 https://en.wikipedia.org/wiki/sha-2 ）：

  for (int j = 0; j < 64; j++) {
    int temp1 = h + rightRotate3(e) + ((e & f) ^ (~e & g)) + K[i] + w.get(i);
    int temp2 = rightRotate4(a) + ((a & b) ^ (a & c) ^ (b & c));
    h = g;
    g = f;
    f = e;
    e = d + temp1;
    d = c;
    c = b;
    b = a;
    a = temp1 + temp2;
  }

您的循环变量是j，但是您使用变量i i < /代码>访问消息时间表阵列（i在处理消息块的外循环中使用）。

正确的代码是

  for (int j = 0; j < 64; j++) {
    int temp1 = h + rightRotate3(e) + ((e & f) ^ (~e & g)) + K[j] + w.get(j);
    int temp2 = rightRotate4(a) + ((a & b) ^ (a & c) ^ (b & c));
    h = g;
    g = f;
    f = e;
    e = d + temp1;
    d = c;
    c = b;
    b = a;
    a = temp1 + temp2;
  }