转载:
http://blog.csdn.net/forgotaboutgirl/article/details/7258109
java代码部分 亲测通过。
这里 就 只贴一下代码吧 。
动作只有 或与非,异或,位移 5个操作,但是组合得很复杂。
四个线性函数(&是与,|是或,~是非,^是异或)
<<<s表示循环左移s位
package com.md5Impl; public class MD5 { static final String hexs[] = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F"}; //下面这些S11-S44实际上是一个4*4的矩阵,在四轮循环运算中用到 static final int S11 = 7; static final int S12 = 12; static final int S13 = 17; static final int S14 = 22; static final int S21 = 5; static final int S22 = 9; static final int S23 = 14; static final int S24 = 20; static final int S31 = 4; static final int S32 = 11; static final int S33 = 16; static final int S34 = 23; static final int S41 = 6; static final int S42 = 10; static final int S43 = 15; static final int S44 = 21; //标准的幻数 private static final long A = 0x67452301L; private static final long B = 0xefcdab89L; private static final long C = 0x98badcfeL; private static final long D = 0x10325476L; //java不支持无符号的基本数据(unsigned) private long[] result = {A, B, C, D};//存储hash结果,共4×32=128位,初始化值为(幻数的级联) public static void main(String[] args) { MD5 md = new MD5(); // System.out.println("md5(abc)=" + md.digest("abc")); System.out.println("md5(abc)=" + md.digest("qwe")); } /** * 从inputBytes的index开始取512位,作为新的分组 * 将每一个512位的分组再细分成16个小组,每个小组64位(8个字节) * * @param inputBytes * @param index * @return */ private static long[] divGroup(byte[] inputBytes, int index) { long[] temp = new long[16]; for (int i = 0; i < 16; i++) { temp[i] = b2iu(inputBytes[4 * i + index]) | (b2iu(inputBytes[4 * i + 1 + index])) << 8 | (b2iu(inputBytes[4 * i + 2 + index])) << 16 | (b2iu(inputBytes[4 * i + 3 + index])) << 24; } return temp; } /** * 这时不存在符号位(符号位存储不再是代表正负),所以需要处理一下 * * @param b * @return */ public static long b2iu(byte b) { return b < 0 ? b & 0x7F + 128 : b; } /** * 下面是处理要用到的线性函数 */ private static long F(long x, long y, long z) { return (x & y) | ((~x) & z); } private static long G(long x, long y, long z) { return (x & z) | (y & (~z)); } private static long H(long x, long y, long z) { return x ^ y ^ z; } private static long I(long x, long y, long z) { return y ^ (x | (~z)); } private static long FF(long a, long b, long c, long d, long x, long s, long ac) { a += (F(b, c, d) & 0xFFFFFFFFL) + x + ac; a = ((a & 0xFFFFFFFFL) << s) | ((a & 0xFFFFFFFFL) >>> (32 - s)); a += b; return (a & 0xFFFFFFFFL); } private static long GG(long a, long b, long c, long d, long x, long s, long ac) { a += (G(b, c, d) & 0xFFFFFFFFL) + x + ac; a = ((a & 0xFFFFFFFFL) << s) | ((a & 0xFFFFFFFFL) >>> (32 - s)); a += b; return (a & 0xFFFFFFFFL); } private static long HH(long a, long b, long c, long d, long x, long s, long ac) { a += (H(b, c, d) & 0xFFFFFFFFL) + x + ac; a = ((a & 0xFFFFFFFFL) << s) | ((a & 0xFFFFFFFFL) >>> (32 - s)); a += b; return (a & 0xFFFFFFFFL); } private static long II(long a, long b, long c, long d, long x, long s, long ac) { a += (I(b, c, d) & 0xFFFFFFFFL) + x + ac; a = ((a & 0xFFFFFFFFL) << s) | ((a & 0xFFFFFFFFL) >>> (32 - s)); a += b; return (a & 0xFFFFFFFFL); } private String digest(String inputStr) { byte[] inputBytes = inputStr.getBytes(); int byteLen = inputBytes.length;//长度(字节) int groupCount = 0;//完整分组的个数 groupCount = byteLen / 64;//每组512位(64字节) long[] groups = null;//每个小组(64字节)再细分后的16个小组(4字节) //处理每一个完整的分组 for (int step = 0; step < groupCount; step++) { groups = divGroup(inputBytes, step * 64); trans(groups);//处理分组,核心算法 } //处理完整分组后的尾巴 int rest = byteLen % 64;//512位分组后的余数 byte[] tempBytes = new byte[64]; if (rest <= 56) { for (int i = 0; i < rest; i++) tempBytes[i] = inputBytes[byteLen - rest + i]; if (rest < 56) { tempBytes[rest] = (byte) (1 << 7); for (int i = 1; i < 56 - rest; i++) tempBytes[rest + i] = 0; } long len = (long) (byteLen << 3); for (int i = 0; i < 8; i++) { tempBytes[56 + i] = (byte) (len & 0xFFL); len = len >> 8; } groups = divGroup(tempBytes, 0); trans(groups);//处理分组 } else { for (int i = 0; i < rest; i++) tempBytes[i] = inputBytes[byteLen - rest + i]; tempBytes[rest] = (byte) (1 << 7); for (int i = rest + 1; i < 64; i++) tempBytes[i] = 0; groups = divGroup(tempBytes, 0); trans(groups);//处理分组 for (int i = 0; i < 56; i++) tempBytes[i] = 0; long len = (long) (byteLen << 3); for (int i = 0; i < 8; i++) { tempBytes[56 + i] = (byte) (len & 0xFFL); len = len >> 8; } groups = divGroup(tempBytes, 0); trans(groups);//处理分组 } //将Hash值转换成十六进制的字符串 String resStr = ""; long temp = 0; for (int i = 0; i < 4; i++) { for (int j = 0; j < 4; j++) { temp = result[i] & 0x0FL; String a = hexs[(int) (temp)]; result[i] = result[i] >> 4; temp = result[i] & 0x0FL; resStr += hexs[(int) (temp)] + a; result[i] = result[i] >> 4; } } return resStr; } /** * 主要的操作,四轮循环 * * @param groups[]--每一个分组512位(64字节) */ private void trans(long[] groups) { long a = result[0], b = result[1], c = result[2], d = result[3]; /*第一轮*/ a = FF(a, b, c, d, groups[0], S11, 0xd76aa478L); /* 1 */ d = FF(d, a, b, c, groups[1], S12, 0xe8c7b756L); /* 2 */ c = FF(c, d, a, b, groups[2], S13, 0x242070dbL); /* 3 */ b = FF(b, c, d, a, groups[3], S14, 0xc1bdceeeL); /* 4 */ a = FF(a, b, c, d, groups[4], S11, 0xf57c0fafL); /* 5 */ d = FF(d, a, b, c, groups[5], S12, 0x4787c62aL); /* 6 */ c = FF(c, d, a, b, groups[6], S13, 0xa8304613L); /* 7 */ b = FF(b, c, d, a, groups[7], S14, 0xfd469501L); /* 8 */ a = FF(a, b, c, d, groups[8], S11, 0x698098d8L); /* 9 */ d = FF(d, a, b, c, groups[9], S12, 0x8b44f7afL); /* 10 */ c = FF(c, d, a, b, groups[10], S13, 0xffff5bb1L); /* 11 */ b = FF(b, c, d, a, groups[11], S14, 0x895cd7beL); /* 12 */ a = FF(a, b, c, d, groups[12], S11, 0x6b901122L); /* 13 */ d = FF(d, a, b, c, groups[13], S12, 0xfd987193L); /* 14 */ c = FF(c, d, a, b, groups[14], S13, 0xa679438eL); /* 15 */ b = FF(b, c, d, a, groups[15], S14, 0x49b40821L); /* 16 */ /*第二轮*/ a = GG(a, b, c, d, groups[1], S21, 0xf61e2562L); /* 17 */ d = GG(d, a, b, c, groups[6], S22, 0xc040b340L); /* 18 */ c = GG(c, d, a, b, groups[11], S23, 0x265e5a51L); /* 19 */ b = GG(b, c, d, a, groups[0], S24, 0xe9b6c7aaL); /* 20 */ a = GG(a, b, c, d, groups[5], S21, 0xd62f105dL); /* 21 */ d = GG(d, a, b, c, groups[10], S22, 0x2441453L); /* 22 */ c = GG(c, d, a, b, groups[15], S23, 0xd8a1e681L); /* 23 */ b = GG(b, c, d, a, groups[4], S24, 0xe7d3fbc8L); /* 24 */ a = GG(a, b, c, d, groups[9], S21, 0x21e1cde6L); /* 25 */ d = GG(d, a, b, c, groups[14], S22, 0xc33707d6L); /* 26 */ c = GG(c, d, a, b, groups[3], S23, 0xf4d50d87L); /* 27 */ b = GG(b, c, d, a, groups[8], S24, 0x455a14edL); /* 28 */ a = GG(a, b, c, d, groups[13], S21, 0xa9e3e905L); /* 29 */ d = GG(d, a, b, c, groups[2], S22, 0xfcefa3f8L); /* 30 */ c = GG(c, d, a, b, groups[7], S23, 0x676f02d9L); /* 31 */ b = GG(b, c, d, a, groups[12], S24, 0x8d2a4c8aL); /* 32 */ /*第三轮*/ a = HH(a, b, c, d, groups[5], S31, 0xfffa3942L); /* 33 */ d = HH(d, a, b, c, groups[8], S32, 0x8771f681L); /* 34 */ c = HH(c, d, a, b, groups[11], S33, 0x6d9d6122L); /* 35 */ b = HH(b, c, d, a, groups[14], S34, 0xfde5380cL); /* 36 */ a = HH(a, b, c, d, groups[1], S31, 0xa4beea44L); /* 37 */ d = HH(d, a, b, c, groups[4], S32, 0x4bdecfa9L); /* 38 */ c = HH(c, d, a, b, groups[7], S33, 0xf6bb4b60L); /* 39 */ b = HH(b, c, d, a, groups[10], S34, 0xbebfbc70L); /* 40 */ a = HH(a, b, c, d, groups[13], S31, 0x289b7ec6L); /* 41 */ d = HH(d, a, b, c, groups[0], S32, 0xeaa127faL); /* 42 */ c = HH(c, d, a, b, groups[3], S33, 0xd4ef3085L); /* 43 */ b = HH(b, c, d, a, groups[6], S34, 0x4881d05L); /* 44 */ a = HH(a, b, c, d, groups[9], S31, 0xd9d4d039L); /* 45 */ d = HH(d, a, b, c, groups[12], S32, 0xe6db99e5L); /* 46 */ c = HH(c, d, a, b, groups[15], S33, 0x1fa27cf8L); /* 47 */ b = HH(b, c, d, a, groups[2], S34, 0xc4ac5665L); /* 48 */ /*第四轮*/ a = II(a, b, c, d, groups[0], S41, 0xf4292244L); /* 49 */ d = II(d, a, b, c, groups[7], S42, 0x432aff97L); /* 50 */ c = II(c, d, a, b, groups[14], S43, 0xab9423a7L); /* 51 */ b = II(b, c, d, a, groups[5], S44, 0xfc93a039L); /* 52 */ a = II(a, b, c, d, groups[12], S41, 0x655b59c3L); /* 53 */ d = II(d, a, b, c, groups[3], S42, 0x8f0ccc92L); /* 54 */ c = II(c, d, a, b, groups[10], S43, 0xffeff47dL); /* 55 */ b = II(b, c, d, a, groups[1], S44, 0x85845dd1L); /* 56 */ a = II(a, b, c, d, groups[8], S41, 0x6fa87e4fL); /* 57 */ d = II(d, a, b, c, groups[15], S42, 0xfe2ce6e0L); /* 58 */ c = II(c, d, a, b, groups[6], S43, 0xa3014314L); /* 59 */ b = II(b, c, d, a, groups[13], S44, 0x4e0811a1L); /* 60 */ a = II(a, b, c, d, groups[4], S41, 0xf7537e82L); /* 61 */ d = II(d, a, b, c, groups[11], S42, 0xbd3af235L); /* 62 */ c = II(c, d, a, b, groups[2], S43, 0x2ad7d2bbL); /* 63 */ b = II(b, c, d, a, groups[9], S44, 0xeb86d391L); /* 64 */ /*加入到之前计算的结果当中*/ result[0] += a; result[1] += b; result[2] += c; result[3] += d; result[0] = result[0] & 0xFFFFFFFFL; result[1] = result[1] & 0xFFFFFFFFL; result[2] = result[2] & 0xFFFFFFFFL; result[3] = result[3] & 0xFFFFFFFFL; } }
至于SHA-1算法,看了这两篇文章,就不想再研究了:
http://www.cnblogs.com/dacainiao/p/5554811.html
http://www.freebuf.com/news/topnews/44288.html
时间: 2024-10-12 12:43:29