Contains internal state of the MD5 class
/*
* MD5 in Java JDK Beta-2
* written Santeri Paavolainen, Helsinki Finland 1996
* (c) Santeri Paavolainen, Helsinki Finland 1996
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* See http://www.cs.hut.fi/~santtu/java/ for more information on this
* class.
*
* This is rather straight re-implementation of the reference implementation
* given in RFC1321 by RSA.
*
* Passes MD5 test suite as defined in RFC1321.
*
*
* This Java class has been derived from the RSA Data Security, Inc. MD5
* Message-Digest Algorithm and its reference implementation.
*
*
* Moved to the net.matuschek.util package for JoBo integration
* replaced deprecated use of String.getBytes()
*/
/**
* Contains internal state of the MD5 class
*/
class MD5State {
/**
* 128-byte state
*/
int state[];
/**
* 64-bit character count (could be true Java long?)
*/
int count[];
/**
* 64-byte buffer (512 bits) for storing to-be-hashed characters
*/
byte buffer[];
public MD5State() {
buffer = new byte[64];
count = new int[2];
state = new int[4];
state[0] = 0x67452301;
state[1] = 0xefcdab89;
state[2] = 0x98badcfe;
state[3] = 0x10325476;
count[0] = count[1] = 0;
}
/** Create this State as a copy of another state */
public MD5State (MD5State from) {
this();
int i;
for (i = 0; i < buffer.length; i++)
this.buffer[i] = from.buffer[i];
for (i = 0; i < state.length; i++)
this.state[i] = from.state[i];
for (i = 0; i < count.length; i++)
this.count[i] = from.count[i];
}
};
/**
* Implementation of RSA's MD5 hash generator
*
* @version $Revision: 1.1 $
* @author Santeri Paavolainen <sjpaavol@cc.helsinki.fi>
*/
public class MD5 {
/**
* MD5 state
*/
MD5State state;
/**
* If Final() has been called, finals is set to the current finals
* state. Any Update() causes this to be set to null.
*/
MD5State finals;
/**
* Padding for Final()
*/
static byte padding[] = {
(byte) 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/**
* Initialize MD5 internal state (object can be reused just by
* calling Init() after every Final()
*/
public synchronized void Init () {
state = new MD5State();
finals = null;
}
/**
* Class constructor
*/
public MD5 () {
this.Init();
}
/**
* Initialize class, and update hash with ob.toString()
*
* @param ob Object, ob.toString() is used to update hash
* after initialization
*/
public MD5 (Object ob) {
this();
Update(ob.toString());
}
private int rotate_left (int x, int n) {
return (x << n) | (x >>> (32 - n));
}
/* I wonder how many loops and hoops you'll have to go through to
get unsigned add for longs in java */
private int uadd (int a, int b) {
long aa, bb;
aa = ((long) a) & 0xffffffffL;
bb = ((long) b) & 0xffffffffL;
aa += bb;
return (int) (aa & 0xffffffffL);
}
private int uadd (int a, int b, int c) {
return uadd(uadd(a, b), c);
}
private int uadd (int a, int b, int c, int d) {
return uadd(uadd(a, b, c), d);
}
private int FF (int a, int b, int c, int d, int x, int s, int ac) {
a = uadd(a, ((b & c) | (~b & d)), x, ac);
return uadd(rotate_left(a, s), b);
}
private int GG (int a, int b, int c, int d, int x, int s, int ac) {
a = uadd(a, ((b & d) | (c & ~d)), x, ac);
return uadd(rotate_left(a, s), b);
}
private int HH (int a, int b, int c, int d, int x, int s, int ac) {
a = uadd(a, (b ^ c ^ d), x, ac);
return uadd(rotate_left(a, s) , b);
}
private int II (int a, int b, int c, int d, int x, int s, int ac) {
a = uadd(a, (c ^ (b | ~d)), x, ac);
return uadd(rotate_left(a, s), b);
}
private int[] Decode (byte buffer[], int len, int shift) {
int out[];
int i, j;
out = new int[16];
for (i = j = 0; j < len; i++, j += 4) {
out[i] = ((int) (buffer[j + shift] & 0xff)) |
(((int) (buffer[j + 1 + shift] & 0xff)) << 8) |
(((int) (buffer[j + 2 + shift] & 0xff)) << 16) |
(((int) (buffer[j + 3 + shift] & 0xff)) << 24);
/* System.out.println("out[" + i + "] = \t" +
((int) buffer[j + 0 + shift] & 0xff) + "\t|\t" +
((int) buffer[j + 1 + shift] & 0xff) + "\t|\t" +
((int) buffer[j + 2 + shift] & 0xff) + "\t|\t" +
((int) buffer[j + 3 + shift] & 0xff));*/
}
return out;
}
private void Transform (MD5State state, byte buffer[], int shift) {
int
a = state.state[0],
b = state.state[1],
c = state.state[2],
d = state.state[3],
x[];
x = Decode(buffer, 64, shift);
/* Round 1 */
a = FF (a, b, c, d, x[ 0], 7, 0xd76aa478); /* 1 */
d = FF (d, a, b, c, x[ 1], 12, 0xe8c7b756); /* 2 */
c = FF (c, d, a, b, x[ 2], 17, 0x242070db); /* 3 */
b = FF (b, c, d, a, x[ 3], 22, 0xc1bdceee); /* 4 */
a = FF (a, b, c, d, x[ 4], 7, 0xf57c0faf); /* 5 */
d = FF (d, a, b, c, x[ 5], 12, 0x4787c62a); /* 6 */
c = FF (c, d, a, b, x[ 6], 17, 0xa8304613); /* 7 */
b = FF (b, c, d, a, x[ 7], 22, 0xfd469501); /* 8 */
a = FF (a, b, c, d, x[ 8], 7, 0x698098d8); /* 9 */
d = FF (d, a, b, c, x[ 9], 12, 0x8b44f7af); /* 10 */
c = FF (c, d, a, b, x[10], 17, 0xffff5bb1); /* 11 */
b = FF (b, c, d, a, x[11], 22, 0x895cd7be); /* 12 */
a = FF (a, b, c, d, x[12], 7, 0x6b901122); /* 13 */
d = FF (d, a, b, c, x[13], 12, 0xfd987193); /* 14 */
c = FF (c, d, a, b, x[14], 17, 0xa679438e); /* 15 */
b = FF (b, c, d, a, x[15], 22, 0x49b40821); /* 16 */
/* Round 2 */
a = GG (a, b, c, d, x[ 1], 5, 0xf61e2562); /* 17 */
d = GG (d, a, b, c, x[ 6], 9, 0xc040b340); /* 18 */
c = GG (c, d, a, b, x[11], 14, 0x265e5a51); /* 19 */
b = GG (b, c, d, a, x[ 0], 20, 0xe9b6c7aa); /* 20 */
a = GG (a, b, c, d, x[ 5], 5, 0xd62f105d); /* 21 */
d = GG (d, a, b, c, x[10], 9, 0x2441453); /* 22 */
c = GG (c, d, a, b, x[15], 14, 0xd8a1e681); /* 23 */
b = GG (b, c, d, a, x[ 4], 20, 0xe7d3fbc8); /* 24 */
a = GG (a, b, c, d, x[ 9], 5, 0x21e1cde6); /* 25 */
d = GG (d, a, b, c, x[14], 9, 0xc33707d6); /* 26 */
c = GG (c, d, a, b, x[ 3], 14, 0xf4d50d87); /* 27 */
b = GG (b, c, d, a, x[ 8], 20, 0x455a14ed); /* 28 */
a = GG (a, b, c, d, x[13], 5, 0xa9e3e905); /* 29 */
d = GG (d, a, b, c, x[ 2], 9, 0xfcefa3f8); /* 30 */
c = GG (c, d, a, b, x[ 7], 14, 0x676f02d9); /* 31 */
b = GG (b, c, d, a, x[12], 20, 0x8d2a4c8a); /* 32 */
/* Round 3 */
a = HH (a, b, c, d, x[ 5], 4, 0xfffa3942); /* 33 */
d = HH (d, a, b, c, x[ 8], 11, 0x8771f681); /* 34 */
c = HH (c, d, a, b, x[11], 16, 0x6d9d6122); /* 35 */
b = HH (b, c, d, a, x[14], 23, 0xfde5380c); /* 36 */
a = HH (a, b, c, d, x[ 1], 4, 0xa4beea44); /* 37 */
d = HH (d, a, b, c, x[ 4], 11, 0x4bdecfa9); /* 38 */
c = HH (c, d, a, b, x[ 7], 16, 0xf6bb4b60); /* 39 */
b = HH (b, c, d, a, x[10], 23, 0xbebfbc70); /* 40 */
a = HH (a, b, c, d, x[13], 4, 0x289b7ec6); /* 41 */
d = HH (d, a, b, c, x[ 0], 11, 0xeaa127fa); /* 42 */
c = HH (c, d, a, b, x[ 3], 16, 0xd4ef3085); /* 43 */
b = HH (b, c, d, a, x[ 6], 23, 0x4881d05); /* 44 */
a = HH (a, b, c, d, x[ 9], 4, 0xd9d4d039); /* 45 */
d = HH (d, a, b, c, x[12], 11, 0xe6db99e5); /* 46 */
c = HH (c, d, a, b, x[15], 16, 0x1fa27cf8); /* 47 */
b = HH (b, c, d, a, x[ 2], 23, 0xc4ac5665); /* 48 */
/* Round 4 */
a = II (a, b, c, d, x[ 0], 6, 0xf4292244); /* 49 */
d = II (d, a, b, c, x[ 7], 10, 0x432aff97); /* 50 */
c = II (c, d, a, b, x[14], 15, 0xab9423a7); /* 51 */
b = II (b, c, d, a, x[ 5], 21, 0xfc93a039); /* 52 */
a = II (a, b, c, d, x[12], 6, 0x655b59c3); /* 53 */
d = II (d, a, b, c, x[ 3], 10, 0x8f0ccc92); /* 54 */
c = II (c, d, a, b, x[10], 15, 0xffeff47d); /* 55 */
b = II (b, c, d, a, x[ 1], 21, 0x85845dd1); /* 56 */
a = II (a, b, c, d, x[ 8], 6, 0x6fa87e4f); /* 57 */
d = II (d, a, b, c, x[15], 10, 0xfe2ce6e0); /* 58 */
c = II (c, d, a, b, x[ 6], 15, 0xa3014314); /* 59 */
b = II (b, c, d, a, x[13], 21, 0x4e0811a1); /* 60 */
a = II (a, b, c, d, x[ 4], 6, 0xf7537e82); /* 61 */
d = II (d, a, b, c, x[11], 10, 0xbd3af235); /* 62 */
c = II (c, d, a, b, x[ 2], 15, 0x2ad7d2bb); /* 63 */
b = II (b, c, d, a, x[ 9], 21, 0xeb86d391); /* 64 */
state.state[0] += a;
state.state[1] += b;
state.state[2] += c;
state.state[3] += d;
}
/**
* Updates hash with the bytebuffer given (using at maximum length bytes from
* that buffer)
*
* @param state Which state is updated
* @param buffer Array of bytes to be hashed
* @param offset Offset to buffer array
* @param length Use at maximum `length' bytes (absolute
* maximum is buffer.length)
*/
public void Update (MD5State stat, byte buffer[], int offset, int length) {
int index, partlen, i, start;
finals = null;
/* Length can be told to be shorter, but not inter */
if ((length - offset)> buffer.length)
length = buffer.length - offset;
/* compute number of bytes mod 64 */
index = (int) (stat.count[0] >>> 3) & 0x3f;
if ((stat.count[0] += (length << 3)) <
(length << 3))
stat.count[1]++;
stat.count[1] += length >>> 29;
partlen = 64 - index;
if (length >= partlen) {
for (i = 0; i < partlen; i++)
stat.buffer[i + index] = buffer[i + offset];
Transform(stat, stat.buffer, 0);
for (i = partlen; (i + 63) < length; i+= 64)
Transform(stat, buffer, i);
index = 0;
} else
i = 0;
/* buffer remaining input */
if (i < length) {
start = i;
for (; i < length; i++)
stat.buffer[index + i - start] = buffer[i + offset];
}
}
/*
* Update()s for other datatypes than byte[] also. Update(byte[], int)
* is only the main driver.
*/
/**
* Plain update, updates this object
*/
public void Update (byte buffer[], int offset, int length) {
Update(this.state, buffer, offset, length);
}
public void Update (byte buffer[], int length) {
Update(this.state, buffer, 0, length);
}
/**
* Updates hash with given array of bytes
*
* @param buffer Array of bytes to use for updating the hash
*/
public void Update (byte buffer[]) {
Update(buffer, 0, buffer.length);
}
/**
* Updates hash with a single byte
*
* @param b Single byte to update the hash
*/
public void Update (byte b) {
byte buffer[] = new byte[1];
buffer[0] = b;
Update(buffer, 1);
}
/**
* Update buffer with given string.
*
* @param s String to be update to hash (is used as
* s.getBytes())
*/
public void Update (String s) {
byte chars[];
chars = s.getBytes();
Update(chars, chars.length);
}
/**
* Update buffer with a single integer (only & 0xff part is used,
* as a byte)
*
* @param i Integer value, which is then converted to
* byte as i & 0xff
*/
public void Update (int i) {
Update((byte) (i & 0xff));
}
private byte[] Encode (int input[], int len) {
int i, j;
byte out[];
out = new byte[len];
for (i = j = 0; j < len; i++, j += 4) {
out[j] = (byte) (input[i] & 0xff);
out[j + 1] = (byte) ((input[i] >>> 8) & 0xff);
out[j + 2] = (byte) ((input[i] >>> 16) & 0xff);
out[j + 3] = (byte) ((input[i] >>> 24) & 0xff);
}
return out;
}
/**
* Returns array of bytes (16 bytes) representing hash as of the
* current state of this object. Note: getting a hash does not
* invalidate the hash object, it only creates a copy of the real
* state which is finalized.
*
* @return Array of 16 bytes, the hash of all updated bytes
*/
public synchronized byte[] Final () {
byte bits[];
int index, padlen;
MD5State fin;
if (finals == null) {
fin = new MD5State(state);
bits = Encode(fin.count, 8);
index = (int) ((fin.count[0] >>> 3) & 0x3f);
padlen = (index < 56) ? (56 - index) : (120 - index);
Update(fin, padding, 0, padlen);
/**/
Update(fin, bits, 0, 8);
/* Update() sets finalds to null */
finals = fin;
}
return Encode(finals.state, 16);
}
/**
* Turns array of bytes into string representing each byte as
* unsigned hex number.
*
* @param hash Array of bytes to convert to hex-string
* @return Generated hex string
*/
public static String asHex (byte hash[]) {
StringBuffer buf = new StringBuffer(hash.length * 2);
int i;
for (i = 0; i < hash.length; i++) {
if (((int) hash[i] & 0xff) < 0x10)
buf.append("0");
buf.append(Long.toString((int) hash[i] & 0xff, 16));
}
return buf.toString();
}
/**
* Returns 32-character hex representation of this objects hash
*
* @return String of this object's hash
*/
public String asHex () {
return asHex(this.Final());
}
}
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