The implementation of MD5 algorithm in JS

js| algorithm

<script language= "JavaScript" >
<!--
/**********************************************************

* Md5.js
*
* A JavaScript Implementation of the RSA Data Security, Inc. MD5
* Message-digest algorithm.
*
* Copyright (C) Paul Johnston 1999. Distributed under the LGPL.
***********************************************************/

* To convert strings to a list of ASCII values * *
var sascii = "!\" #$%& ' () *+,-./0123456789:;<=>? @ABCDEFGHIJKLMNOPQRSTUVWXYZ "
var sascii = Sascii + "[\\]^_ ' abcdefghijklmnopqrstuvwxyz{|}" ~";

/* Convert integer to hex String * *
var ShEx = "0123456789ABCDEF";
function Hex (i)
{
h = "";
for (j = 0; J <= 3; j + +)
{
H + + Shex.charat ((i >> (J * 8 + 4)) & 0x0f) +
Shex.charat ((I >> (J * 8)) & 0x0f);
}
return h;
}

/* Add, handling overflows correctly * *
function add (x, y)
{
Return ((X&0X7FFFFFFF) + (Y&0X7FFFFFFF)) ^ (x&0x80000000) ^ (y&0x80000000);
}

/* MD5 rounds functions * *
function R1 (A, B, C, D, X, S, T)
{
Q = Add (Add (A, (B & C) | (~b & D)), add (X, T));
return Add (q << S) | (q >> (32-s)) & (Math.pow (2, S)-1), B);
}

function R2 (A, B, C, D, X, S, T)
{
Q = Add (Add (A, (B & D) | (C & ~d)), add (X, T));
return Add (q << S) | (q >> (32-s)) & (Math.pow (2, S)-1), B);
}

function R3 (A, B, C, D, X, S, T)
{
Q = Add (Add (A, B ^ C ^ D), add (X, T));
return Add (q << S) | (q >> (32-s)) & (Math.pow (2, S)-1), B);
}

function R4 (A, B, C, D, X, S, T)
{
Q = Add (Add (A, C ^ (B | ~d)), add (X, T));
return Add (q << S) | (q >> (32-s)) & (Math.pow (2, S)-1), B);
}

/* Main entry point * *
function CalcMD5 (SINP) {

/* Calculate length in machine words, including padding * *
Wlen = ((Sinp.length + 8) >> 6) + 1) << 4;
var X = new Array (Wlen);

/* Convert string to array of words * *
j = 4;
for (i = 0; (i * 4) < sinp.length; i++)
{
X[i] = 0;
for (j = 0; (J < 4) && ((j + i * 4) < sinp.length); J + +)
{
X[i] + + (Sascii.indexof (Sinp.charat (i * 4) + j)) << (J * 8);
}
}

/* Append padding bits and length * *
if (j = = 4)
{
x[i++] = 0x80;
}
Else
{
X[I-1] + + 0x80 << (J * 8);
}
for (; i < Wlen; i++) {x[i] = 0;}
X[WLEN-2] = sinp.length * 8;

/* hard-coded Initial values * *
A = 0x67452301;
b = 0xefcdab89;
c = 0x98badcfe;
D = 0x10325476;

/* Process each 16-word blocks in turn * *
for (i = 0; i < Wlen i + + 16) {
AO = A;
BO = b;
CO = C;
do = D;

A = R1 (A, B, C, D, x[i+ 0], 7, 0xd76aa478);
D = R1 (d, a, B, C, x[i+ 1], 0xe8c7b756);
C = R1 (c, D, a, B, x[i+ 2], 0x242070db);
B = R1 (b, C, D, A, x[i+ 3], 0xc1bdceee);
A = R1 (A, B, C, D, x[i+ 4], 7, 0XF57C0FAF);
D = R1 (d, a, B, C, x[i+ 5], 0x4787c62a);
C = R1 (c, D, a, B, x[i+ 6], 0xa8304613);
B = R1 (b, C, D, A, x[i+ 7], 0xfd469501);
A = R1 (A, B, C, D, x[i+ 8], 7, 0X698098D8);
D = R1 (d, a, B, C, x[i+ 9], 0X8B44F7AF);
C = R1 (c, D, a, B, x[i+10], 0XFFFF5BB1);
B = R1 (b, C, D, A, x[i+11], 0x895cd7be);
A = R1 (A, B, C, D, X[i+12], 7, 0x6b901122);
D = R1 (d, a, B, C, x[i+13], 0xfd987193);
C = R1 (c, D, a, B, x[i+14], 0xa679438e);
B = R1 (b, C, D, A, x[i+15], 0x49b40821);

A = R2 (A, B, C, D, x[i+ 1], 5, 0xf61e2562);
D = R2 (d, a, B, C, x[i+ 6], 9, 0xc040b340);
C = R2 (c, D, a, B, x[i+11], 0x265e5a51);
B = R2 (b, C, D, A, x[i+ 0], 0XE9B6C7AA);
A = R2 (A, B, C, D, x[i+ 5], 5, 0xd62f105d);
D = R2 (d, a, B, C, x[i+10], 9, 0x2441453);
C = R2 (c, D, a, B, x[i+15], 0xd8a1e681);
B = R2 (b, C, D, A, x[i+ 4], 0XE7D3FBC8);
A = R2 (A, B, C, D, x[i+ 9], 5, 0x21e1cde6);
D = R2 (d, a, B, C, x[i+14], 9, 0xc33707d6);
C = R2 (c, D, a, B, x[i+ 3], 0xf4d50d87);
B = R2 (b, C, D, A, x[i+ 8], 0x455a14ed);
A = R2 (A, B, C, D, X[i+13], 5, 0xa9e3e905);
D = R2 (d, a, B, C, x[i+ 2], 9, 0XFCEFA3F8);
C = R2 (c, D, a, B, x[i+ 7], 0x676f02d9);
B = R2 (b, C, D, A, x[i+12], 0x8d2a4c8a);

A = R3 (A, B, C, D, x[i+ 5], 4, 0xfffa3942);
D = R3 (d, a, B, C, x[i+ 8], one, 0x8771f681);
C = R3 (c, D, a, B, x[i+11], 0x6d9d6122);
B = R3 (b, C, D, A, x[i+14], 0xfde5380c);
A = R3 (A, B, C, D, x[i+ 1], 4, 0xa4beea44);
D = R3 (d, a, B, C, x[i+ 4], one, 0x4bdecfa9);
C = R3 (c, D, a, B, x[i+ 7], 0xf6bb4b60);
B = R3 (b, C, D, A, x[i+10], 0XBEBFBC70);
A = R3 (A, B, C, D, X[i+13], 4, 0X289B7EC6);
D = R3 (d, a, B, C, x[i+ 0], one, 0XEAA127FA);
C = R3 (c, D, a, B, x[i+ 3], 0xd4ef3085);
B = R3 (b, C, D, A, x[i+ 6], 0x4881d05);
A = R3 (A, B, C, D, x[i+ 9], 4, 0xd9d4d039);
D = R3 (d, a, B, C, x[i+12], one, 0xe6db99e5);
C = R3 (c, D, a, B, x[i+15], 0x1fa27cf8);
B = R3 (b, C, D, A, x[i+ 2], 0xc4ac5665);

A = R4 (A, B, C, D, x[i+ 0], 6, 0xf4292244);
D = R4 (d, a, B, C, x[i+ 7], 0x432aff97);
c = R4 (c, D, a, B, x[i+14], 0xab9423a7);
b = R4 (b, C, D, A, x[i+ 5], 0xfc93a039);
A = R4 (A, B, C, D, X[i+12], 6, 0X655B59C3);
D = R4 (d, a, B, C, x[i+ 3], 0x8f0ccc92);
c = R4 (c, D, a, B, x[i+10], 0xffeff47d);
b = R4 (b, C, D, A, x[i+ 1], 0X85845DD1);
A = R4 (A, B, C, D, x[i+ 8], 6, 0x6fa87e4f);
D = R4 (d, a, B, C, x[i+15], 0xfe2ce6e0);
c = R4 (c, D, a, B, x[i+ 6], 0xa3014314);
b = R4 (b, C, D, A, x[i+13], 0X4E0811A1);
A = R4 (A, B, C, D, x[i+ 4], 6, 0xf7537e82);
D = R4 (d, a, B, C, x[i+11], 0xbd3af235);
c = R4 (c, D, a, B, x[i+ 2], 0X2AD7D2BB);
b = R4 (b, C, D, A, x[i+ 9], 0xeb86d391);

A = Add (A, AO);
b = Add (b, BO);
c = Add (c, CO);
D = Add (d, do);
}
Return Hex (a) + hex (b) + hex (c) + hex (d);
}

Alert (Hex ("123456"))
-->
</script>