md5.java

MD5加密源码

package cn.gov.eq.util;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.io.UnsupportedEncodingException;

public class MD5 {
    private static final int BUFFER_SIZE = 1024;

    private static final int S11 = 7;
    private static final int S12 = 12;
    private static final int S13 = 17;
    private static final int S14 = 22;
    private static final int S21 = 5;
    private static final int S22 = 9;
    private static final int S23 = 14;
    private static final int S24 = 20;
    private static final int S31 = 4;
    private static final int S32 = 11;
    private static final int S33 = 16;
    private static final int S34 = 23;
    private static final int S41 = 6;
    private static final int S42 = 10;
    private static final int S43 = 15;
    private static final int S44 = 21;

    private static byte padding[] = {
      (byte) 0x80, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0,
      (byte) 0, (byte) 0,
      (byte) 0, (byte) 0, (byte) 0, (byte) 0
    };

    private InputStream in = null;
    private boolean stringp = false;
    private int state[] = null;
    private long count = 0;
    private byte buffer[] = null;
    private byte digest[] = null;

    private static String stringify(byte buf[]) {
        StringBuffer sb = new StringBuffer(2 * buf.length);
        for (int i = 0; i < buf.length; i++) {
            int h = (buf[i] & 0xf0) >> 4;
            int l = (buf[i] & 0x0f);
            sb.append(new Character((char) ((h > 9) ? 'a' + h - 10 : '0' + h)));
            sb.append(new Character((char) ((l > 9) ? 'a' + l - 10 : '0' + l)));
        }
        return sb.toString();
    }

    private final int F(int x, int y, int z) {
        return ((x & y) | ((~x) & z));
    }

    private final int G(int x, int y, int z) {
        return ((x & z) | (y & (~z)));
    }

    private final int H(int x, int y, int z) {
        return (x ^ y ^ z);
    }

    private final int I(int x, int y, int z) {
        return (y ^ (x | (~z)));
    }

    private final int rotate_left(int x, int n) {
        return ((x << n) | (x >>> (32 - n)));
    }

    private final int FF(int a, int b, int c, int d, int x, int s, int ac) {
        a += (F(b, c, d) + x + ac);
        a = rotate_left(a, s);
        a += b;
        return a;
    }

    private final int GG(int a, int b, int c, int d, int x, int s, int ac) {
        a += (G(b, c, d) + x + ac);
        a = rotate_left(a, s);
        a += b;
        return a;
    }

    private final int HH(int a, int b, int c, int d, int x, int s, int ac) {
        a += (H(b, c, d) + x + ac);
        a = rotate_left(a, s);
        a += b;
        return a;
    }

    private final int II(int a, int b, int c, int d, int x, int s, int ac) {
        a += (I(b, c, d) + x + ac);
        a = rotate_left(a, s);
        a += b;
        return a;
    }

    private final void decode(int output[], byte input[], int off, int len) {
        int i = 0;
        int j = 0;
        for (; j < len; i++, j += 4) {
            output[i] = (((int) (input[off + j] & 0xff))
                         | (((int) (input[off + j + 1] & 0xff)) << 8)
                         | (((int) (input[off + j + 2] & 0xff)) << 16)
                         | (((int) (input[off + j + 3] & 0xff)) << 24));
        }
    }

    private final void transform(byte block[], int offset) {
        int a = state[0];
        int b = state[1];
        int c = state[2];
        int d = state[3];
        int x[] = new int[16];

        decode(x, block, offset, 64);
        /* Round 1 */
        a = FF(a, b, c, d, x[0], S11, 0xd76aa478); /* 1 */
        d = FF(d, a, b, c, x[1], S12, 0xe8c7b756); /* 2 */
        c = FF(c, d, a, b, x[2], S13, 0x242070db); /* 3 */
        b = FF(b, c, d, a, x[3], S14, 0xc1bdceee); /* 4 */
        a = FF(a, b, c, d, x[4], S11, 0xf57c0faf); /* 5 */
        d = FF(d, a, b, c, x[5], S12, 0x4787c62a); /* 6 */
        c = FF(c, d, a, b, x[6], S13, 0xa8304613); /* 7 */
        b = FF(b, c, d, a, x[7], S14, 0xfd469501); /* 8 */
        a = FF(a, b, c, d, x[8], S11, 0x698098d8); /* 9 */
        d = FF(d, a, b, c, x[9], S12, 0x8b44f7af); /* 10 */
        c = FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
        b = FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
        a = FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
        d = FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
        c = FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
        b = FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
        /* Round 2 */
        a = GG(a, b, c, d, x[1], S21, 0xf61e2562); /* 17 */
        d = GG(d, a, b, c, x[6], S22, 0xc040b340); /* 18 */
        c = GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
        b = GG(b, c, d, a, x[0], S24, 0xe9b6c7aa); /* 20 */
        a = GG(a, b, c, d, x[5], S21, 0xd62f105d); /* 21 */
        d = GG(d, a, b, c, x[10], S22, 0x2441453); /* 22 */
        c = GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
        b = GG(b, c, d, a, x[4], S24, 0xe7d3fbc8); /* 24 */
        a = GG(a, b, c, d, x[9], S21, 0x21e1cde6); /* 25 */
        d = GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
        c = GG(c, d, a, b, x[3], S23, 0xf4d50d87); /* 27 */
        b = GG(b, c, d, a, x[8], S24, 0x455a14ed); /* 28 */
        a = GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
        d = GG(d, a, b, c, x[2], S22, 0xfcefa3f8); /* 30 */
        c = GG(c, d, a, b, x[7], S23, 0x676f02d9); /* 31 */
        b = GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */

        /* Round 3 */
        a = HH(a, b, c, d, x[5], S31, 0xfffa3942); /* 33 */
        d = HH(d, a, b, c, x[8], S32, 0x8771f681); /* 34 */
        c = HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
        b = HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
        a = HH(a, b, c, d, x[1], S31, 0xa4beea44); /* 37 */
        d = HH(d, a, b, c, x[4], S32, 0x4bdecfa9); /* 38 */
        c = HH(c, d, a, b, x[7], S33, 0xf6bb4b60); /* 39 */
        b = HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
        a = HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
        d = HH(d, a, b, c, x[0], S32, 0xeaa127fa); /* 42 */
        c = HH(c, d, a, b, x[3], S33, 0xd4ef3085); /* 43 */
        b = HH(b, c, d, a, x[6], S34, 0x4881d05); /* 44 */
        a = HH(a, b, c, d, x[9], S31, 0xd9d4d039); /* 45 */
        d = HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
        c = HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
        b = HH(b, c, d, a, x[2], S34, 0xc4ac5665); /* 48 */

        /* Round 4 */
        a = II(a, b, c, d, x[0], S41, 0xf4292244); /* 49 */
        d = II(d, a, b, c, x[7], S42, 0x432aff97); /* 50 */
        c = II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
        b = II(b, c, d, a, x[5], S44, 0xfc93a039); /* 52 */
        a = II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
        d = II(d, a, b, c, x[3], S42, 0x8f0ccc92); /* 54 */
        c = II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
        b = II(b, c, d, a, x[1], S44, 0x85845dd1); /* 56 */
        a = II(a, b, c, d, x[8], S41, 0x6fa87e4f); /* 57 */
        d = II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
        c = II(c, d, a, b, x[6], S43, 0xa3014314); /* 59 */
        b = II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
        a = II(a, b, c, d, x[4], S41, 0xf7537e82); /* 61 */
        d = II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
        c = II(c, d, a, b, x[2], S43, 0x2ad7d2bb); /* 63 */
        b = II(b, c, d, a, x[9], S44, 0xeb86d391); /* 64 */

        state[0] += a;
        state[1] += b;
        state[2] += c;
        state[3] += d;
    }

    private final void update(byte input[], int len) {
        int index = ((int) (count >> 3)) & 0x3f;
        count += (len << 3);
        int partLen = 64 - index;
        int i = 0;
        if (len >= partLen) {
            System.arraycopy(input, 0, buffer, index, partLen);
            transform(buffer, 0);
            for (i = partLen; i + 63 < len; i += 64)
                transform(input, i);
            index = 0;
        } else {
            i = 0;
        }
        System.arraycopy(input, i, buffer, index, len - i);
    }

    private byte[] end() {
        byte bits[] = new byte[8];
        for (int i = 0; i < 8; i++)
            bits[i] = (byte) ((count >>> (i * 8)) & 0xff);
        int index = ((int) (count >> 3)) & 0x3f;
        int padlen = (index < 56) ? (56 - index) : (120 - index);
        update(padding, padlen);
        update(bits, 8);
        return encode(state, 16);
    }

    // Encode the content.state array into 16 bytes array
    private byte[] encode(int input[], int len) {
        byte output[] = new byte[len];
        int i = 0;
        int j = 0;
        for (; j < len; i++, j += 4) {
            output[j] = (byte) ((input[i]) & 0xff);
            output[j + 1] = (byte) ((input[i] >> 8) & 0xff);
            output[j + 2] = (byte) ((input[i] >> 16) & 0xff);
            output[j + 3] = (byte) ((input[i] >> 24) & 0xff);
        }
        return output;
    }

    /**
     * Get the digest for our input stream.
     * This method constructs the input stream digest, and return it, as a
     * a String, following the MD5 (rfc1321) algorithm,
     * @return An instance of String, giving the message digest.
     * @exception IOException Thrown if the digestifier was unable to read the
     *    input stream.
     */

    public byte[] getDigest() throws IOException {
        byte buffer[] = new byte[BUFFER_SIZE];
        int got = -1;

        if (digest != null)
            return digest;
        while ((got = in.read(buffer)) > 0)
            update(buffer, got);
        this.digest = end();
        return digest;
    }

    /**
     * Get the digest, for this string digestifier.
     * This method doesn't throw any IOException, since it knows that the
     * underlying stream ws built from a String.
     */

    public byte[] processString() {
        if (!stringp)
            throw new RuntimeException(this.getClass().getName()
                                       + "[processString]"
                                       + " not a string.");
        try {
            return getDigest();
        } catch (IOException ex) {
        }
        throw new RuntimeException(this.getClass().getName()
                                   + "[processString]"
                                   + ": implementation error.");
    }

    /**
     * Get the digest, as a proper string.
     */

    public String getStringDigest() {
        if (digest == null)
            throw new RuntimeException(this.getClass().getName()
                                       + "[getStringDigest]"
                                       + ": called before processing.");
        return stringify(digest);
    }

    /**
     * Construct a digestifier for the given string.
     * @param input The string to be digestified.
     * @param encoding the encoding name used (such as UTF8)
     */

    public MD5(String input, String enc) {
        byte bytes[] = null;
        try {
            bytes = input.getBytes(enc);
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException("no " + enc + " encoding!!!");
        }
        this.stringp = true;
        this.in = new ByteArrayInputStream(bytes);
        this.state = new int[4];
        this.buffer = new byte[64];
        this.count = 0;
        state[0] = 0x67452301;
        state[1] = 0xefcdab89;
        state[2] = 0x98badcfe;
        state[3] = 0x10325476;
    }

    /**
     * Construct a digestifier for the given string.
     * @param input The string to be digestified.
     */

    public MD5(String input) {
        this(input, "UTF8");
    }

    /**
     * Construct a digestifier for the given input stream.
     * @param in The input stream to be digestified.
     */

    public MD5(InputStream in) {
        this.stringp = false;
        this.in = in;
        this.state = new int[4];
        this.buffer = new byte[64];
        this.count = 0;
        state[0] = 0x67452301;
        state[1] = 0xefcdab89;
        state[2] = 0x98badcfe;
        state[3] = 0x10325476;
    }

    public static String generateDigest(String sSrc) {
        if (sSrc == null)
            return null;

        MD5 md5 = new MD5(sSrc);
        try {
            byte bs[] = md5.getDigest();
            return MD5.stringify(bs);
        } catch (Exception e) {
            return null;
        }
    }

    public static void main(String args[]) throws IOException {
        MD5 md5 = new MD5("Beijing2008");
        byte bs[] = md5.getDigest();
        System.out.println(MD5.stringify(bs));
        System.out.println("1.9bd429854baffea1bb26bf75b9033a5f");
        System.out.println("2." + md5.getStringDigest());
        System.out.print("3." + MD5.generateDigest(null));
    }
}