Implements MD5 functionality on a stream.
/*
* Implements MD5 functionality on a stream.
*
* written Santeri Paavolainen, Helsinki Finland 1996
* (c) Santeri Paavolainen, Helsinki Finland 1996
* modifications Copyright (C) 2002 Stephen Ostermiller
* http://ostermiller.org/contact.pl?regarding=Java+Utilities
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* See COPYING.TXT for details.
*
* The original work by Santeri Paavolainen can be found a
* http://www.helsinki.fi/~sjpaavol/programs/md5/
*/
import java.io.*;
/**
* Implements MD5 functionality on a stream.
* More information about this class is available from <a target="_top" href=
* "http://ostermiller.org/utils/MD5.html">ostermiller.org</a>.
* <p>
* This class produces a 128-bit "fingerprint" or "message digest" for
* all data written to this stream.
* It is conjectured that it is computationally infeasible to produce
* two messages having the same message digest, or to produce any
* message having a given pre-specified target message digest. The MD5
* algorithm is intended for digital signature applications, where a
* large file must be "compressed" in a secure manner before being
* encrypted with a private (secret) key under a public-key cryptosystem
* such as RSA.
* <p>
* For more information see RFC1321.
*
* @see MD5
* @see MD5InputStream
*
* @author Santeri Paavolainen http://www.helsinki.fi/~sjpaavol/programs/md5/
* @author Stephen Ostermiller http://ostermiller.org/contact.pl?regarding=Java+Utilities
* @since ostermillerutils 1.00.00
*/
public class MD5OutputStream extends FilterOutputStream {
/**
* MD5 context
*/
private MD5 md5;
/**
* Creates MD5OutputStream
* @param out The output stream
*
* @since ostermillerutils 1.00.00
*/
public MD5OutputStream(OutputStream out) {
super(out);
md5 = new MD5();
}
/**
* Writes the specified byte to this output stream.
*
* @param b the byte.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
@Override public void write(int b) throws IOException {
out.write(b);
md5.update((byte)(b & 0xff));
}
/**
* Writes length bytes from the specified byte array starting a
* offset off to this output stream.
*
* @param b the data.
* @param off the start offset in the data.
* @param len the number of bytes to write.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
@Override public void write(byte b[], int off, int len) throws IOException {
out.write(b, off, len);
md5.update(b, off, len);
}
/**
* Returns array of bytes representing hash of the stream so far.
*
* @return Array of 16 bytes, the hash of all written bytes.
*
* @since ostermillerutils 1.00.00
*/
public byte[] getHash(){
return md5.getHash();
}
/**
* Get a 32-character hex representation representing hash of the stream so far.
*
* @return A string containing the hash of all written bytes.
*
* @since ostermillerutils 1.00.00
*/
public String getHashString(){
return md5.getHashString();
}
}
class MD5 {
/**
* Class constructor
*
* @since ostermillerutils 1.00.00
*/
public MD5 () {
reset();
}
/**
* Command line program that will take files as arguments
* and output the MD5 sum for each file.
*
* @param args command line arguments
*
* @since ostermillerutils 1.00.00
*/
public static void main (String[] args){
if (args.length == 0){
System.err.println("Please specify a file.");
} else {
for (String element: args) {
try {
System.out.println(MD5.getHashString(new File(element)) + " " + element);
} catch (IOException x){
System.err.println(x.getMessage());
}
}
}
}
/**
* Gets this hash sum as an array of 16 bytes.
*
* @return Array of 16 bytes, the hash of all updated bytes.
*
* @since ostermillerutils 1.00.00
*/
public byte[] getHash() {
if (!finalState.valid) {
finalState.copy(workingState);
long bitCount = finalState.bitCount;
// Compute the number of left over bits
int leftOver = (int) (((bitCount >>> 3)) & 0x3f);
// Compute the amount of padding to add based on number of left over bits.
int padlen = (leftOver < 56) ? (56 - leftOver) : (120 - leftOver);
// add the padding
update(finalState, padding, 0, padlen);
// add the length (computed before padding was added)
update(finalState, encode(bitCount), 0, 8);
finalState.valid = true;
}
// make a copy of the hash before returning it.
return encode(finalState.state, 16);
}
/**
* Returns 32-character hex representation of this hash.
*
* @return String representation of this object's hash.
*
* @since ostermillerutils 1.00.00
*/
public String getHashString(){
return toHex(this.getHash());
}
/**
* Gets the MD5 hash of the given byte array.
*
* @param b byte array for which an MD5 hash is desired.
* @return Array of 16 bytes, the hash of all updated bytes.
*
* @since ostermillerutils 1.00.00
*/
public static byte[] getHash(byte[] b){
MD5 md5 = new MD5();
md5.update(b);
return md5.getHash();
}
/**
* Gets the MD5 hash of the given byte array.
*
* @param b byte array for which an MD5 hash is desired.
* @return 32-character hex representation the data's MD5 hash.
*
* @since ostermillerutils 1.00.00
*/
public static String getHashString(byte[] b){
MD5 md5 = new MD5();
md5.update(b);
return md5.getHashString();
}
/**
* Gets the MD5 hash the data on the given InputStream.
*
* @param in byte array for which an MD5 hash is desired.
* @return Array of 16 bytes, the hash of all updated bytes.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static byte[] getHash(InputStream in) throws IOException {
MD5 md5 = new MD5();
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1){
md5.update(buffer, read);
}
return md5.getHash();
}
/**
* Gets the MD5 hash the data on the given InputStream.
*
* @param in byte array for which an MD5 hash is desired.
* @return 32-character hex representation the data's MD5 hash.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static String getHashString(InputStream in) throws IOException {
MD5 md5 = new MD5();
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1){
md5.update(buffer, read);
}
return md5.getHashString();
}
/**
* Gets the MD5 hash of the given file.
*
* @param f file for which an MD5 hash is desired.
* @return Array of 16 bytes, the hash of all updated bytes.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static byte[] getHash(File f) throws IOException {
InputStream is = new FileInputStream(f);
byte[] hash = getHash(is);
is.close();
return hash;
}
/**
* Gets the MD5 hash of the given file.
*
* @param f file array for which an MD5 hash is desired.
* @return 32-character hex representation the data's MD5 hash.
* @throws IOException if an I/O error occurs.
*
* @since ostermillerutils 1.00.00
*/
public static String getHashString(File f) throws IOException {
InputStream is = new FileInputStream(f);
String hash = getHashString(is);
is.close();
return hash;
}
/**
* Gets the MD5 hash of the given String.
* The string is converted to bytes using the current
* platform's default character encoding.
*
* @param s String for which an MD5 hash is desired.
* @return Array of 16 bytes, the hash of all updated bytes.
*
* @since ostermillerutils 1.00.00
*/
public static byte[] getHash(String s){
MD5 md5 = new MD5();
md5.update(s);
return md5.getHash();
}
/**
* Gets the MD5 hash of the given String.
* The string is converted to bytes using the current
* platform's default character encoding.
*
* @param s String for which an MD5 hash is desired.
* @return 32-character hex representation the data's MD5 hash.
*
* @since ostermillerutils 1.00.00
*/
public static String getHashString(String s){
MD5 md5 = new MD5();
md5.update(s);
return md5.getHashString();
}
/**
* Gets the MD5 hash of the given String.
*
* @param s String for which an MD5 hash is desired.
* @param enc The name of a supported character encoding.
* @return Array of 16 bytes, the hash of all updated bytes.
* @throws UnsupportedEncodingException If the named encoding is not supported.
*
* @since ostermillerutils 1.00.00
*/
public static byte[] getHash(String s, String enc) throws UnsupportedEncodingException {
MD5 md5 = new MD5();
md5.update(s, enc);
return md5.getHash();
}
/**
* Gets the MD5 hash of the given String.
*
* @param s String for which an MD5 hash is desired.
* @param enc The name of a supported character encoding.
* @return 32-character hex representation the data's MD5 hash.
* @throws UnsupportedEncodingException If the named encoding is not supported.
*
* @since ostermillerutils 1.00.00
*/
public static String getHashString(String s, String enc) throws UnsupportedEncodingException {
MD5 md5 = new MD5();
md5.update(s, enc);
return md5.getHashString();
}
/**
* Reset the MD5 sum to its initial state.
*
* @since ostermillerutils 1.00.00
*/
public void reset() {
workingState.reset();
finalState.valid = false;
}
/**
* Returns 32-character hex representation of this hash.
*
* @return String representation of this object's hash.
*
* @since ostermillerutils 1.00.00
*/
@Override public String toString(){
return getHashString();
}
/**
* Update this hash with the given data.
* <p>
* A state may be passed into this method so that we can add padding
* and finalize a md5 hash without limiting our ability to update
* more data later.
* <p>
* If length bytes are not available to be hashed, as many bytes as
* possible will be hashed.
*
* @param state Which state is updated.
* @param buffer Array of bytes to be hashed.
* @param offset Offset to buffer array.
* @param length number of bytes to hash.
*
* @since ostermillerutils 1.00.00
*/
private void update (MD5State state, byte buffer[], int offset, int length) {
finalState.valid = false;
// if length goes beyond the end of the buffer, cut it short.
if ((length + offset) > buffer.length){
length = buffer.length - offset;
}
// compute number of bytes mod 64
// this is what we have sitting in a buffer
// that have not been hashed yet
int index = (int) (state.bitCount >>> 3) & 0x3f;
// add the length to the count (translate bytes to bits)
state.bitCount += length << 3;
int partlen = 64 - index;
int i = 0;
if (length >= partlen) {
System.arraycopy(buffer, offset, state.buffer, index, partlen);
transform(state, decode(state.buffer, 64, 0));
for (i = partlen; (i + 63) < length; i+= 64){
transform(state, decode(buffer, 64, i));
}
index = 0;
}
// buffer remaining input
if (i < length) {
for (int start = i; i < length; i++) {
state.buffer[index + i - start] = buffer[i + offset];
}
}
}
/**
* Update this hash with the given data.
* <p>
* If length bytes are not available to be hashed, as many bytes as
* possible will be hashed.
*
* @param buffer Array of bytes to be hashed.
* @param offset Offset to buffer array.
* @param length number of bytes to hash.
*
* @since ostermillerutils 1.00.00
*/
public void update (byte buffer[], int offset, int length) {
update(workingState, buffer, offset, length);
}
/**
* Update this hash with the given data.
* <p>
* If length bytes are not available to be hashed, as many bytes as
* possible will be hashed.
*
* @param buffer Array of bytes to be hashed.
* @param length number of bytes to hash.
*
* @since ostermillerutils 1.00.00
*/
public void update (byte buffer[], int length) {
update(buffer, 0, length);
}
/**
* Update this hash with the given data.
*
* @param buffer Array of bytes to be hashed.
*
* @since ostermillerutils 1.00.00
*/
public void update (byte buffer[]) {
update(buffer, 0, buffer.length);
}
/**
* Updates this hash with a single byte.
*
* @param b byte to be hashed.
*
* @since ostermillerutils 1.00.00
*/
public void update (byte b) {
byte buffer[] = new byte[1];
buffer[0] = b;
update(buffer, 1);
}
/**
* Update this hash with a String.
* The string is converted to bytes using the current
* platform's default character encoding.
*
* @param s String to be hashed.
*
* @since ostermillerutils 1.00.00
*/
public void update (String s) {
update(s.getBytes());
}
/**
* Update this hash with a String.
*
* @param s String to be hashed.
* @param enc The name of a supported character encoding.
* @throws UnsupportedEncodingException If the named encoding is not supported.
*
* @since ostermillerutils 1.00.00
*/
public void update (String s, String enc) throws UnsupportedEncodingException {
update(s.getBytes(enc));
}
/**
* The current state from which the hash sum
* can be computed or updated.
*
* @since ostermillerutils 1.00.00
*/
private MD5State workingState = new MD5State();
/**
* Cached copy of the final MD5 hash sum. This is created when
* the hash is requested and it is invalidated when the hash
* is updated.
*
* @since ostermillerutils 1.00.00
*/
private MD5State finalState = new MD5State();
/**
* Temporary buffer cached here for performance reasons.
*
* @since ostermillerutils 1.00.00
*/
private int[] decodeBuffer = new int[16];
/**
* 64 bytes of padding that can be added if the length
* is not divisible by 64.
*
* @since ostermillerutils 1.00.00
*/
private static final 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,
};
/**
* Contains internal state of the MD5 class.
* Passes MD5 test suite as defined in RFC1321.
*
* @since ostermillerutils 1.00.00
*/
private class MD5State {
/**
* True if this state is valid.
*
* @since ostermillerutils 1.00.00
*/
private boolean valid = true;
/**
* Reset to initial state.
*
* @since ostermillerutils 1.00.00
*/
private void reset(){
state[0] = 0x67452301;
state[1] = 0xefcdab89;
state[2] = 0x98badcfe;
state[3] = 0x10325476;
bitCount = 0;
}
/**
* 128-byte state
*
* @since ostermillerutils 1.00.00
*/
private int state[] = new int[4];
/**
* 64-bit count of the number of bits that have been hashed.
*
* @since ostermillerutils 1.00.00
*/
private long bitCount;
/**
* 64-byte buffer (512 bits) for storing to-be-hashed characters
*
* @since ostermillerutils 1.00.00
*/
private byte buffer[] = new byte[64];
private MD5State() {
reset();
}
/**
* Set this state to be exactly the same as some other.
*
* @param from state to copy from.
*
* @since ostermillerutils 1.00.00
*/
private void copy(MD5State from) {
System.arraycopy(from.buffer, 0, this.buffer, 0, this.buffer.length);
System.arraycopy(from.state, 0, this.state, 0, this.state.length);
this.valid = from.valid;
this.bitCount = from.bitCount;
}
}
/**
* Turns array of bytes into string representing each byte as
* a two digit unsigned hex number.
*
* @param hash Array of bytes to convert to hex-string
* @return Generated hex string
*
* @since ostermillerutils 1.00.00
*/
private static String toHex(byte hash[]){
StringBuffer buf = new StringBuffer(hash.length * 2);
for (byte element: hash) {
int intVal = element & 0xff;
if (intVal < 0x10){
// append a zero before a one digit hex
// number to make it two digits.
buf.append("0");
}
buf.append(Integer.toHexString(intVal));
}
return buf.toString();
}
private static int FF (int a, int b, int c, int d, int x, int s, int ac) {
a += ((b & c) | (~b & d));
a += x;
a += ac;
//return rotateLeft(a, s) + b;
a = (a << s) | (a >>> (32 - s));
return a + b;
}
private static int GG (int a, int b, int c, int d, int x, int s, int ac) {
a += ((b & d) | (c & ~d));
a += x;
a += ac;
//return rotateLeft(a, s) + b;
a = (a << s) | (a >>> (32 - s));
return a + b;
}
private static int HH (int a, int b, int c, int d, int x, int s, int ac) {
a += (b ^ c ^ d);
a += x;
a += ac;
//return rotateLeft(a, s) + b;
a = (a << s) | (a >>> (32 - s));
return a + b;
}
private static int II (int a, int b, int c, int d, int x, int s, int ac) {
a += (c ^ (b | ~d));
a += x;
a += ac;
//return rotateLeft(a, s) + b;
a = (a << s) | (a >>> (32 - s));
return a + b;
}
private static byte[] encode(long l){
byte[] out = new byte[8];
out[0] = (byte) (l & 0xff);
out[1] = (byte) ((l >>> 8) & 0xff);
out[2] = (byte) ((l >>> 16) & 0xff);
out[3] = (byte) ((l >>> 24) & 0xff);
out[4] = (byte) ((l >>> 32) & 0xff);
out[5] = (byte) ((l >>> 40) & 0xff);
out[6] = (byte) ((l >>> 48) & 0xff);
out[7] = (byte) ((l >>> 56) & 0xff);
return out;
}
private static byte[] encode(int input[], int len){
byte[] out = new byte[len];
int i, j;
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;
}
private int[] decode(byte buffer[], int len, int offset){
int i, j;
for (i = j = 0; j < len; i++, j += 4) {
decodeBuffer[i] = (
(buffer[j + offset] & 0xff)) |
(((buffer[j + 1 + offset] & 0xff)) << 8) |
(((buffer[j + 2 + offset] & 0xff)) << 16) |
(((buffer[j + 3 + offset] & 0xff)) << 24
);
}
return decodeBuffer;
}
private static void transform(MD5State state, int[] x){
int a = state.state[0];
int b = state.state[1];
int c = state.state[2];
int d = state.state[3];
/* 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, 0x02441453); /* 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, 0x04881d05); /* 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;
}
}
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