© 2005 Goetz Heller
Table of Contents Description Examples Copyright Note back /// JavaScript MD4 message digest algorithm
///
/// This software is derived from intellectual property of RSA Data
/// Security Inc. and therefore underlies the following copyright:
///
/// Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
/// rights reserved.
///
/// License to copy and use this software is granted provided that it
/// is identified as the "RSA Data Security, Inc. MD4 Message-Digest
/// Algorithm" in all material mentioning or referencing this software
/// or this function.
///
/// License is also granted to make and use derivative works provided
/// that such works are identified as "derived from the RSA Data
/// Security, Inc. MD4 Message-Digest Algorithm" in all material
/// mentioning or referencing the derived work.
///
/// RSA Data Security, Inc. makes no representations concerning either
/// the merchantability of this software or the suitability of this
/// software for any particular purpose. It is provided "as is"
/// without express or implied warranty of any kind.
///
/// These notices must be retained in any copies of any part of this
/// documentation and/or software.
///
/// This implementation is based on RFC 1320. The functions and their prototypes follow
/// the microsoft patterns for encryption service providers. Since JavaScript makes it
/// difficult to execute bit operations in a consistent way (these are done with signed
/// 32-bit integers, but mostly numbers are represented internally in a different manner)
/// we have tried to avoid them largely. Since it is not expected that this implementation
/// will handle large amounts of data efficiency was not considered a primary goal.
///
/// Goetz Heller
/// Dr.Heller Information Management
/// 08.02.2005
/// Dependencies
/// genhash.js
// class system.security.encryption.hash.MD4
try {
if (system.security.encryption.hash.MD4 == null) {
throw new Error('');
}
} catch(e) { // don't install twice
// dependencies
try {
eval('core');
} catch(e) {
throw new Error('MD4: class \'core\' not installed');
}
// get base class
var baseClass = core.getClassByID('system.security.encryption.hash.hashAlgorithm');
// constructor
var MD4 = function() {};
// provide for class information
MD4.classID = function() {
return 'system.security.encryption.hash.MD4';
};
//disallow subclassing
MD4.isFinal = function() {
return true;
};
// define class constants
MD4.iInputBlockSize = 64;
MD4.iOutputBlockSize = 16;
MD4.hashSize = 128;
// constants for the MD4 transform routine
MD4.S11 = 3;
MD4.S12 = 7;
MD4.S13 = 11;
MD4.S14 = 19;
MD4.S21 = 3;
MD4.S22 = 5;
MD4.S23 = 9;
MD4.S24 = 13;
MD4.S31 = 3;
MD4.S32 = 9;
MD4.S33 = 11;
MD4.S34 = 15;
MD4.PADDING = [
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
];
// make it a subclass of hashAlgorithm
core.derive(MD4, baseClass);
// setup data structure of instance
MD4.prototype.initialize = function() {
this.state = [0x0000, 0x0000, 0x0000, 0x0000]; // state (ABCD) (uint)
this.bcount = [0x00,0x00]; // number of bits, modulo 2^64 (2 * uint, lsb first)
core.getClassByID('system.security.encryption.hash.hashAlgorithm').prototype.initialize.call(this);
this.reset();
};
// reset data structures: begins an MD4 operation, writing a new context.
MD4.prototype.reset = function() {
// reset baseclass
core.getClassByID('system.security.encryption.hash.hashAlgorithm').prototype.reset.call(this);
// reset bit counter
for (var i = 0; i < this.bcount.length; i++) {
this.bcount[i] = 0x00;
}
// set magic initialization constants.
this.state[0] = 0x67452301;
this.state[1] = 0xefcdab89;
this.state[2] = 0x98badcfe;
this.state[3] = 0x10325476;
};
// F, G, and H are basic MD4 functions
MD4.prototype.F = function(x, y, z)
{
return ((x & y) | (~x & z));
}
MD4.prototype.G = function(x, y, z)
{
return ((x & y) | (x & z) | (y & z));
}
MD4.prototype.H = function(x, y, z)
{
return (x ^ y ^ z);
}
// ROTATE_LEFT rotates x left n bits.
MD4.prototype.ROTATE_LEFT = function(x, n)
{
// has been adapted to deal correctly with the javascript switching
// between 32-bit signed ints and standard representation correctly
if (n==0) return x;
var s = (x&0x80000000) ? 0x80000000 : 0;
x -= s;
var l = (((x << n) & 0x80000000) ? 0x80000000 : 0) + ((x << n) & 0x7fffffff);
var r = (((x >> (32 - n)) >> 31) ? 0x8000000 : 0) + ((x >> (32 - n)) & 0x7fffffff);
if (s > 0) s = (0x40000000 >> (31 - n));
return (s + l + r);
}
// FF, GG, and HH are transformations for rounds 1, 2, and 3.
// Rotation is separate from addition to prevent recomputation.
MD4.prototype.FF = function(a, b, c, d, x, s)
{
// argument a must be passed as an array!!
var t = this.F(b, c, d);
t = ((t&0x80000000) ? 0x80000000 : 0) + (t&0x7fffffff); // get value as unsigned
a[0] += t + x;
a[0] %= 0x100000000;
a[0] = this.ROTATE_LEFT(a[0], s);
}
MD4.prototype.GG = function(a, b, c, d, x, s) {
// argument a must be passed as an array!!
var t = this.G(b, c, d);
t = ((t&0x80000000) ? 0x80000000 : 0) + (t&0x7fffffff); // get value as unsigned
a[0] += t + x + 0x5a827999;
a[0] %= 0x100000000;
a[0] = this.ROTATE_LEFT(a[0], s);
}
MD4.prototype.HH = function(a, b, c, d, x, s)
{
// argument a must be passed as an array!!
var t = this.H(b, c, d);
t = ((t&0x80000000) ? 0x80000000 : 0) + (t&0x7fffffff); // get value as unsigned
a[0] += t + x + 0x6ed9eba1;
a[0] %= 0x100000000;
a[0] = this.ROTATE_LEFT(a[0], s);
}
/// Encodes input (UINT4) into output (unsigned char). Assumes len is
/// a multiple of 4.
MD4.prototype.Encode = function(out, inp, len) {
var i = 0;
for (var j = 0; j < len; i++, j += 4)
{
var t = inp[i];
for (var k = 0; k < 4; k++) {
out[j + k] = t & 0xff; t /= 0x100;
}
}
}
/// Decodes input (unsigned char) into output (UINT4). Assumes len is
/// a multiple of 4.
MD4.prototype.Decode = function(out, inp, start, len)
{
var i = 0;
if (typeof inp == 'string') {
for (var j = 0; j < len; i++, j += 4) {
out[i] = inp.charCodeAt(start + j) * 1
+ inp.charCodeAt(start + j + 1) * 0x100
+ inp.charCodeAt(start + j + 2) * 0x10000
+ inp.charCodeAt(start + j + 3) * 0x1000000;
}
} else {
for (var j = 0; j < len; i++, j += 4) {
out[i] = inp[start + j] * 1
+ inp[start + j + 1] * 0x100
+ inp[start + j + 2] * 0x10000
+ inp[start + j + 3] * 0x1000000;
}
}
}
/// MD4 basic transformation. Transforms state based on block.
MD4.prototype.Transform = function(block, start) {
var a = new Array(1);
var b = new Array(1);
var c = new Array(1);
var d = new Array(1);
a[0] = ((this.state[0]&0x80000000) ? 0x80000000 : 0) + (this.state[0]&0x7fffffff);
b[0] = ((this.state[1]&0x80000000) ? 0x80000000 : 0) + (this.state[1]&0x7fffffff);
c[0] = ((this.state[2]&0x80000000) ? 0x80000000 : 0) + (this.state[2]&0x7fffffff);
d[0] = ((this.state[3]&0x80000000) ? 0x80000000 : 0) + (this.state[3]&0x7fffffff);
var x = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
this.Decode (x, block, start, this.iInputBlockSize);
// Round 1
this.FF (a, b[0], c[0], d[0], x[ 0], this.S11); // 1
this.FF (d, a[0], b[0], c[0], x[ 1], this.S12); // 2
this.FF (c, d[0], a[0], b[0], x[ 2], this.S13); // 3
this.FF (b, c[0], d[0], a[0], x[ 3], this.S14); // 4
this.FF (a, b[0], c[0], d[0], x[ 4], this.S11); // 5
this.FF (d, a[0], b[0], c[0], x[ 5], this.S12); // 6
this.FF (c, d[0], a[0], b[0], x[ 6], this.S13); // 7
this.FF (b, c[0], d[0], a[0], x[ 7], this.S14); // 8
this.FF (a, b[0], c[0], d[0], x[ 8], this.S11); // 9
this.FF (d, a[0], b[0], c[0], x[ 9], this.S12); // 10
this.FF (c, d[0], a[0], b[0], x[10], this.S13); // 11
this.FF (b, c[0], d[0], a[0], x[11], this.S14); // 12
this.FF (a, b[0], c[0], d[0], x[12], this.S11); // 13
this.FF (d, a[0], b[0], c[0], x[13], this.S12); // 14
this.FF (c, d[0], a[0], b[0], x[14], this.S13); // 15
this.FF (b, c[0], d[0], a[0], x[15], this.S14); // 16
// Round 2
this.GG (a, b[0], c[0], d[0], x[ 0], this.S21); // 17
this.GG (d, a[0], b[0], c[0], x[ 4], this.S22); // 18
this.GG (c, d[0], a[0], b[0], x[ 8], this.S23); // 19
this.GG (b, c[0], d[0], a[0], x[12], this.S24); // 20
this.GG (a, b[0], c[0], d[0], x[ 1], this.S21); // 21
this.GG (d, a[0], b[0], c[0], x[ 5], this.S22); // 22
this.GG (c, d[0], a[0], b[0], x[ 9], this.S23); // 23
this.GG (b, c[0], d[0], a[0], x[13], this.S24); // 24
this.GG (a, b[0], c[0], d[0], x[ 2], this.S21); // 25
this.GG (d, a[0], b[0], c[0], x[ 6], this.S22); // 26
this.GG (c, d[0], a[0], b[0], x[10], this.S23); // 27
this.GG (b, c[0], d[0], a[0], x[14], this.S24); // 28
this.GG (a, b[0], c[0], d[0], x[ 3], this.S21); // 29
this.GG (d, a[0], b[0], c[0], x[ 7], this.S22); // 30
this.GG (c, d[0], a[0], b[0], x[11], this.S23); // 31
this.GG (b, c[0], d[0], a[0], x[15], this.S24); // 32
// Round 3
this.HH (a, b[0], c[0], d[0], x[ 0], this.S31); // 33
this.HH (d, a[0], b[0], c[0], x[ 8], this.S32); // 34
this.HH (c, d[0], a[0], b[0], x[ 4], this.S33); // 35
this.HH (b, c[0], d[0], a[0], x[12], this.S34); // 36
this.HH (a, b[0], c[0], d[0], x[ 2], this.S31); // 37
this.HH (d, a[0], b[0], c[0], x[10], this.S32); // 38
this.HH (c, d[0], a[0], b[0], x[ 6], this.S33); // 39
this.HH (b, c[0], d[0], a[0], x[14], this.S34); // 40
this.HH (a, b[0], c[0], d[0], x[ 1], this.S31); // 41
this.HH (d, a[0], b[0], c[0], x[ 9], this.S32); // 42
this.HH (c, d[0], a[0], b[0], x[ 5], this.S33); // 43
this.HH (b, c[0], d[0], a[0], x[13], this.S34); // 44
this.HH (a, b[0], c[0], d[0], x[ 3], this.S31); // 45
this.HH (d, a[0], b[0], c[0], x[11], this.S32); // 46
this.HH (c, d[0], a[0], b[0], x[ 7], this.S33); // 47
this.HH (b, c[0], d[0], a[0], x[15], this.S34); // 48
this.state[0] += ((a[0]&0x80000000) ? 0x80000000 : 0) + (a[0] & 0x7fffffff);
this.state[1] += ((b[0]&0x80000000) ? 0x80000000 : 0) + (b[0] & 0x7fffffff);
this.state[2] += ((c[0]&0x80000000) ? 0x80000000 : 0) + (c[0] & 0x7fffffff);
this.state[3] += ((d[0]&0x80000000) ? 0x80000000 : 0) + (d[0] & 0x7fffffff);
for (var j = 0; j < this.state.length; j++) {
this.state[j] %= 0x100000000;
}
// Zeroize sensitive information
for (var i = 0; i < x.length; i++) {
x[i] = 0x00;
}
return;
}
// MD4 finalization. Ends an MD4 message-digest operation, writing
// the message digest and zeroizing the context. Returns digest as string.
MD4.prototype.hashFinal = function() {
try
{
var bits = [0, 0, 0, 0, 0, 0, 0, 0];
// Save number of bits
this.Encode (bits, this.bcount, bits.length);
// Pad out to 56 mod 64.
var index = (this.bcount[0] >> 3) & 0x3f;
var padLen = (index < 56) ? (56 - index) : (120 - index);
this.hashCore(this.PADDING, 0, padLen);
// Append length (before padding)
this.hashCore(bits, 0, bits.length);
// Store state in digest
this.Encode (this.hashValue, this.state, this.hashValue.length);
// Zeroize sensitive information.
for (var i = 0; i < this.bcount.length; i++) {
this.bcount[i] = 0x00;
}
for (var i = 0; i < this.state.length; i++) {
this.state[i] = 0x0000;
}
}
catch(e) {}
this.buildHash();
return this.hash;
}
// MD4 block update operation. Continues an MD4 message-digest operation,
// processing another message block, and updating the context.
MD4.prototype.hashCore = function(inp, ibStart, cbSize)
{
var i = 0;
// Compute number of bytes mod 64
var index = ((this.bcount[0] - this.bcount[0]%8)/8)%0x40;
// Update number of bits
if ((this.bcount[0] += (cbSize * 8))%0x10000 < (cbSize * 8)%0x100000000) {
this.bcount[1]++;
}
this.bcount[1] += (cbSize - cbSize%0x20000000)/0x20000000;
this.bcount[1] %= 0x100000000;
var partLen = this.iInputBlockSize - index;
// Transform as many times as possible.
if (cbSize >= partLen)
{
if (typeof inp == 'string') {
for (var j = 0; j < partLen; j++) {
this.buffer[index + j] = inp.charCodeAt(ibStart + j);
}
} else {
for (var j = 0; j < partLen; j++) {
this.buffer[index + j] = inp[ibStart + j];
}
}
this.Transform(this.buffer, 0);
for (i = partLen; i + this.iInputBlockSize <= cbSize; i += this.iInputBlockSize)
{
this.Transform(inp, i);
}
index = 0;
}
// Buffer remaining input
if (typeof inp == 'string') {
for (var j = 0; j < cbSize - i; j++) {
this.buffer[index + j] = inp.charCodeAt(i+j);
}
} else {
for (var j = 0; j < cbSize - i; j++) {
this.buffer[index + j] = inp[i+j];
}
}
}
// install class
core.installClass(MD4);
} // end catch