JS常用加密编码与算法实例总结

本文实例讲述了JS常用加密编码与算法。分享给大家供大家参考，具体如下：

一：UTF8编码函数

function URLEncode(Str){
 if(Str==null||Str=="")
  return "";
 var newStr="";
 function toCase(sStr){
  return sStr.toString(16).toUpperCase();
  }
 for(var i=0,icode,len=Str.length;i=0x30&&icode<=0x39)||(icode>=0x41&&icode<=0x5A)||(icode>=0x61&&icode<=0x7A))
    newStr+=Str.charAt(i);
   else
    newStr+="%"+toCase(icode);
   }
  else if(icode<0x800){
   newStr+="%"+toCase(0xC0+(icode>>6));
   newStr+="%"+toCase(0x80+icode%0x40);
   }
  else{
   newStr+="%"+toCase(0xE0+(icode>>12));
   newStr+="%"+toCase(0x80+(icode>>6)%0x40);
   newStr+="%"+toCase(0x80+icode%0x40);
   }
  }
 return newStr;
 }

二：Base64编码,解码函数

var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var base64DecodeChars = new Array(
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
  52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
  -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
  15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
  -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
  41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1);
function base64encode(str) {
  var out, i, len;
  var c1, c2, c3;
  len = str.length;
  i = 0;
  out = "";
  while(i < len) {
  c1 = str.charCodeAt(i++) & 0xff;
  if(i == len)
  {
    out += base64EncodeChars.charAt(c1 >> 2);
    out += base64EncodeChars.charAt((c1 & 0x3) << 4);
    out += "==";
    break;
  }
  c2 = str.charCodeAt(i++);
  if(i == len)
  {
    out += base64EncodeChars.charAt(c1 >> 2);
    out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
    out += base64EncodeChars.charAt((c2 & 0xF) << 2);
    out += "=";
    break;
  }
  c3 = str.charCodeAt(i++);
  out += base64EncodeChars.charAt(c1 >> 2);
  out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
  out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6));
  out += base64EncodeChars.charAt(c3 & 0x3F);
  }
  return out;
}
function base64decode(str) {
  var c1, c2, c3, c4;
  var i, len, out;
  len = str.length;
  i = 0;
  out = "";
  while(i < len) {
  /* c1 */
  do {
    c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
  } while(i < len && c1 == -1);
  if(c1 == -1)
    break;
  /* c2 */
  do {
    c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff];
  } while(i < len && c2 == -1);
  if(c2 == -1)
    break;
  out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4));
  /* c3 */
  do {
    c3 = str.charCodeAt(i++) & 0xff;
    if(c3 == 61)
    return out;
    c3 = base64DecodeChars[c3];
  } while(i < len && c3 == -1);
  if(c3 == -1)
    break;
  out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2));
  /* c4 */
  do {
    c4 = str.charCodeAt(i++) & 0xff;
    if(c4 == 61)
    return out;
    c4 = base64DecodeChars[c4];
  } while(i < len && c4 == -1);
  if(c4 == -1)
    break;
  out += String.fromCharCode(((c3 & 0x03) << 6) | c4);
  }
  return out;
}
function utf16to8(str) {
  var out, i, len, c;
  out = "";
  len = str.length;
  for(i = 0; i < len; i++) {
  c = str.charCodeAt(i);
  if ((c >= 0x0001) && (c <= 0x007F)) {
    out += str.charAt(i);
  } else if (c > 0x07FF) {
    out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
    out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
    out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
  } else {
    out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
    out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
  }
  }
  return out;
}
function utf8to16(str) {
  var out, i, len, c;
  var char2, char3;
  out = "";
  len = str.length;
  i = 0;
  while(i < len) {
  c = str.charCodeAt(i++);
  switch(c >> 4)
  {
   case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
    // 0xxxxxxx
    out += str.charAt(i-1);
    break;
   case 12: case 13:
    // 110x xxxx 10xx xxxx
    char2 = str.charCodeAt(i++);
    out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F));
    break;
   case 14:
    // 1110 xxxx 10xx xxxx 10xx xxxx
    char2 = str.charCodeAt(i++);
    char3 = str.charCodeAt(i++);
    out += String.fromCharCode(((c & 0x0F) << 12) |
            ((char2 & 0x3F) << 6) |
            ((char3 & 0x3F) << 0));
    break;
  }
  }
  return out;
}
function doit() {
  var f = document.f
  f.output.value = base64encode(utf16to8(f.source.value))
  f.decode.value = utf8to16(base64decode(f.output.value))
}

三：MD5

/*
 * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
 * Digest Algorithm, as defined in RFC 1321.
 * Version 2.1 Copyright (C) Paul Johnston 1999 - 2002.
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for more info.
 */
/*
 * Configurable variables. You may need to tweak these to be compatible with
 * the server-side, but the defaults work in most cases.
 */
var hexcase = 0; /* hex output format. 0 - lowercase; 1 - uppercase    */
var b64pad = ""; /* base-64 pad character. "=" for strict RFC compliance  */
var chrsz  = 8; /* bits per input character. 8 - ASCII; 16 - Unicode   */
/*
 * These are the functions you'll usually want to call
 * They take string arguments and return either hex or base-64 encoded strings
 */
function hex_md5(s){ return binl2hex(core_md5(str2binl(s), s.length * chrsz));}
function b64_md5(s){ return binl2b64(core_md5(str2binl(s), s.length * chrsz));}
function str_md5(s){ return binl2str(core_md5(str2binl(s), s.length * chrsz));}
function hex_hmac_md5(key, data) { return binl2hex(core_hmac_md5(key, data)); }
function b64_hmac_md5(key, data) { return binl2b64(core_hmac_md5(key, data)); }
function str_hmac_md5(key, data) { return binl2str(core_hmac_md5(key, data)); }
/*
 * Perform a simple self-test to see if the VM is working
 */
function md5_vm_test()
{
 return hex_md5("abc") == "900150983cd24fb0d6963f7d28e17f72";
}
/*
 * Calculate the MD5 of an array of little-endian words, and a bit length
 */
function core_md5(x, len)
{
 /* append padding */
 x[len >> 5] |= 0x80 << ((len) % 32);
 x[(((len + 64) >>> 9) << 4) + 14] = len;
 var a = 1732584193;
 var b = -271733879;
 var c = -1732584194;
 var d = 271733878;
 for(var i = 0; i < x.length; i += 16)
 {
  var olda = a;
  var oldb = b;
  var oldc = c;
  var oldd = d;
  a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);
  d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);
  c = md5_ff(c, d, a, b, x[i+ 2], 17, 606105819);
  b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);
  a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);
  d = md5_ff(d, a, b, c, x[i+ 5], 12, 1200080426);
  c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);
  b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);
  a = md5_ff(a, b, c, d, x[i+ 8], 7 , 1770035416);
  d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);
  c = md5_ff(c, d, a, b, x[i+10], 17, -42063);
  b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162);
  a = md5_ff(a, b, c, d, x[i+12], 7 , 1804603682);
  d = md5_ff(d, a, b, c, x[i+13], 12, -40341101);
  c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290);
  b = md5_ff(b, c, d, a, x[i+15], 22, 1236535329);
  a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);
  d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
  c = md5_gg(c, d, a, b, x[i+11], 14, 643717713);
  b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);
  a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);
  d = md5_gg(d, a, b, c, x[i+10], 9 , 38016083);
  c = md5_gg(c, d, a, b, x[i+15], 14, -660478335);
  b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);
  a = md5_gg(a, b, c, d, x[i+ 9], 5 , 568446438);
  d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);
  c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);
  b = md5_gg(b, c, d, a, x[i+ 8], 20, 1163531501);
  a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);
  d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);
  c = md5_gg(c, d, a, b, x[i+ 7], 14, 1735328473);
  b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734);
  a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);
  d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);
  c = md5_hh(c, d, a, b, x[i+11], 16, 1839030562);
  b = md5_hh(b, c, d, a, x[i+14], 23, -35309556);
  a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
  d = md5_hh(d, a, b, c, x[i+ 4], 11, 1272893353);
  c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);
  b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640);
  a = md5_hh(a, b, c, d, x[i+13], 4 , 681279174);
  d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);
  c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);
  b = md5_hh(b, c, d, a, x[i+ 6], 23, 76029189);
  a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);
  d = md5_hh(d, a, b, c, x[i+12], 11, -421815835);
  c = md5_hh(c, d, a, b, x[i+15], 16, 530742520);
  b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);
  a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);
  d = md5_ii(d, a, b, c, x[i+ 7], 10, 1126891415);
  c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905);
  b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);
  a = md5_ii(a, b, c, d, x[i+12], 6 , 1700485571);
  d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);
  c = md5_ii(c, d, a, b, x[i+10], 15, -1051523);
  b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);
  a = md5_ii(a, b, c, d, x[i+ 8], 6 , 1873313359);
  d = md5_ii(d, a, b, c, x[i+15], 10, -30611744);
  c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);
  b = md5_ii(b, c, d, a, x[i+13], 21, 1309151649);
  a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);
  d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379);
  c = md5_ii(c, d, a, b, x[i+ 2], 15, 718787259);
  b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551);
  a = safe_add(a, olda);
  b = safe_add(b, oldb);
  c = safe_add(c, oldc);
  d = safe_add(d, oldd);
 }
 return Array(a, b, c, d);
}
/*
 * These functions implement the four basic operations the algorithm uses.
 */
function md5_cmn(q, a, b, x, s, t)
{
 return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b);
}
function md5_ff(a, b, c, d, x, s, t)
{
 return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t);
}
function md5_gg(a, b, c, d, x, s, t)
{
 return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t);
}
function md5_hh(a, b, c, d, x, s, t)
{
 return md5_cmn(b ^ c ^ d, a, b, x, s, t);
}
function md5_ii(a, b, c, d, x, s, t)
{
 return md5_cmn(c ^ (b | (~d)), a, b, x, s, t);
}
/*
 * Calculate the HMAC-MD5, of a key and some data
 */
function core_hmac_md5(key, data)
{
 var bkey = str2binl(key);
 if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz);
 var ipad = Array(16), opad = Array(16);
 for(var i = 0; i < 16; i++)
 {
  ipad[i] = bkey[i] ^ 0x36363636;
  opad[i] = bkey[i] ^ 0x5C5C5C5C;
 }
 var hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz);
 return core_md5(opad.concat(hash), 512 + 128);
}
/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */
function safe_add(x, y)
{
 var lsw = (x & 0xFFFF) + (y & 0xFFFF);
 var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
 return (msw << 16) | (lsw & 0xFFFF);
}
/*
 * Bitwise rotate a 32-bit number to the left.
 */
function bit_rol(num, cnt)
{
 return (num << cnt) | (num >>> (32 - cnt));
}
/*
 * Convert a string to an array of little-endian words
 * If chrsz is ASCII, characters >255 have their hi-byte silently ignored.
 */
function str2binl(str)
{
 var bin = Array();
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < str.length * chrsz; i += chrsz)
  bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);
 return bin;
}
/*
 * Convert an array of little-endian words to a string
 */
function binl2str(bin)
{
 var str = "";
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < bin.length * 32; i += chrsz)
  str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);
 return str;
}
/*
 * Convert an array of little-endian words to a hex string.
 */
function binl2hex(binarray)
{
 var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i++)
 {
  str += hex_tab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +
      hex_tab.charAt((binarray[i>>2] >> ((i%4)*8 )) & 0xF);
 }
 return str;
}
/*
 * Convert an array of little-endian words to a base-64 string
 */
function binl2b64(binarray)
{
 var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i += 3)
 {
  var triplet = (((binarray[i  >> 2] >> 8 * ( i  %4)) & 0xFF) << 16)
        | (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )
        | ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);
  for(var j = 0; j < 4; j++)
  {
   if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
   else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
  }
 }
 return str;
}

MD4算法

/*
 * A JavaScript implementation of the RSA Data Security, Inc. MD4 Message
 * Digest Algorithm, as defined in RFC 1320.
 * Version 2.1 Copyright (C) Jerrad Pierce, Paul Johnston 1999 - 2002.
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for more info.
 */
/*
 * Configurable variables. You may need to tweak these to be compatible with
 * the server-side, but the defaults work in most cases.
 */
var hexcase = 0; /* hex output format. 0 - lowercase; 1 - uppercase    */
var b64pad = ""; /* base-64 pad character. "=" for strict RFC compliance  */
var chrsz  = 8; /* bits per input character. 8 - ASCII; 16 - Unicode   */
/*
 * These are the functions you'll usually want to call
 */
function hex_md4(s){ return binl2hex(core_md4(str2binl(s), s.length * chrsz));}
function b64_md4(s){ return binl2b64(core_md4(str2binl(s), s.length * chrsz));}
function str_md4(s){ return binl2str(core_md4(str2binl(s), s.length * chrsz));}
function hex_hmac_md4(key, data) { return binl2hex(core_hmac_md4(key, data)); }
function b64_hmac_md4(key, data) { return binl2b64(core_hmac_md4(key, data)); }
function str_hmac_md4(key, data) { return binl2str(core_hmac_md4(key, data)); }
/*
 * Perform a simple self-test to see if the VM is working
 */
function md4_vm_test()
{
 return hex_md4("abc") == "a448017aaf21d8525fc10ae87aa6729d";
}
/*
 * Calculate the MD4 of an array of little-endian words, and a bit length
 */
function core_md4(x, len)
{
 /* append padding */
 x[len >> 5] |= 0x80 << (len % 32);
 x[(((len + 64) >>> 9) << 4) + 14] = len;
 var a = 1732584193;
 var b = -271733879;
 var c = -1732584194;
 var d = 271733878;
 for(var i = 0; i < x.length; i += 16)
 {
  var olda = a;
  var oldb = b;
  var oldc = c;
  var oldd = d;
  a = md4_ff(a, b, c, d, x[i+ 0], 3 );
  d = md4_ff(d, a, b, c, x[i+ 1], 7 );
  c = md4_ff(c, d, a, b, x[i+ 2], 11);
  b = md4_ff(b, c, d, a, x[i+ 3], 19);
  a = md4_ff(a, b, c, d, x[i+ 4], 3 );
  d = md4_ff(d, a, b, c, x[i+ 5], 7 );
  c = md4_ff(c, d, a, b, x[i+ 6], 11);
  b = md4_ff(b, c, d, a, x[i+ 7], 19);
  a = md4_ff(a, b, c, d, x[i+ 8], 3 );
  d = md4_ff(d, a, b, c, x[i+ 9], 7 );
  c = md4_ff(c, d, a, b, x[i+10], 11);
  b = md4_ff(b, c, d, a, x[i+11], 19);
  a = md4_ff(a, b, c, d, x[i+12], 3 );
  d = md4_ff(d, a, b, c, x[i+13], 7 );
  c = md4_ff(c, d, a, b, x[i+14], 11);
  b = md4_ff(b, c, d, a, x[i+15], 19);
  a = md4_gg(a, b, c, d, x[i+ 0], 3 );
  d = md4_gg(d, a, b, c, x[i+ 4], 5 );
  c = md4_gg(c, d, a, b, x[i+ 8], 9 );
  b = md4_gg(b, c, d, a, x[i+12], 13);
  a = md4_gg(a, b, c, d, x[i+ 1], 3 );
  d = md4_gg(d, a, b, c, x[i+ 5], 5 );
  c = md4_gg(c, d, a, b, x[i+ 9], 9 );
  b = md4_gg(b, c, d, a, x[i+13], 13);
  a = md4_gg(a, b, c, d, x[i+ 2], 3 );
  d = md4_gg(d, a, b, c, x[i+ 6], 5 );
  c = md4_gg(c, d, a, b, x[i+10], 9 );
  b = md4_gg(b, c, d, a, x[i+14], 13);
  a = md4_gg(a, b, c, d, x[i+ 3], 3 );
  d = md4_gg(d, a, b, c, x[i+ 7], 5 );
  c = md4_gg(c, d, a, b, x[i+11], 9 );
  b = md4_gg(b, c, d, a, x[i+15], 13);
  a = md4_hh(a, b, c, d, x[i+ 0], 3 );
  d = md4_hh(d, a, b, c, x[i+ 8], 9 );
  c = md4_hh(c, d, a, b, x[i+ 4], 11);
  b = md4_hh(b, c, d, a, x[i+12], 15);
  a = md4_hh(a, b, c, d, x[i+ 2], 3 );
  d = md4_hh(d, a, b, c, x[i+10], 9 );
  c = md4_hh(c, d, a, b, x[i+ 6], 11);
  b = md4_hh(b, c, d, a, x[i+14], 15);
  a = md4_hh(a, b, c, d, x[i+ 1], 3 );
  d = md4_hh(d, a, b, c, x[i+ 9], 9 );
  c = md4_hh(c, d, a, b, x[i+ 5], 11);
  b = md4_hh(b, c, d, a, x[i+13], 15);
  a = md4_hh(a, b, c, d, x[i+ 3], 3 );
  d = md4_hh(d, a, b, c, x[i+11], 9 );
  c = md4_hh(c, d, a, b, x[i+ 7], 11);
  b = md4_hh(b, c, d, a, x[i+15], 15);
  a = safe_add(a, olda);
  b = safe_add(b, oldb);
  c = safe_add(c, oldc);
  d = safe_add(d, oldd);
 }
 return Array(a, b, c, d);
}
/*
 * These functions implement the basic operation for each round of the
 * algorithm.
 */
function md4_cmn(q, a, b, x, s, t)
{
 return safe_add(rol(safe_add(safe_add(a, q), safe_add(x, t)), s), b);
}
function md4_ff(a, b, c, d, x, s)
{
 return md4_cmn((b & c) | ((~b) & d), a, 0, x, s, 0);
}
function md4_gg(a, b, c, d, x, s)
{
 return md4_cmn((b & c) | (b & d) | (c & d), a, 0, x, s, 1518500249);
}
function md4_hh(a, b, c, d, x, s)
{
 return md4_cmn(b ^ c ^ d, a, 0, x, s, 1859775393);
}
/*
 * Calculate the HMAC-MD4, of a key and some data
 */
function core_hmac_md4(key, data)
{
 var bkey = str2binl(key);
 if(bkey.length > 16) bkey = core_md4(bkey, key.length * chrsz);
 var ipad = Array(16), opad = Array(16);
 for(var i = 0; i < 16; i++)
 {
  ipad[i] = bkey[i] ^ 0x36363636;
  opad[i] = bkey[i] ^ 0x5C5C5C5C;
 }
 var hash = core_md4(ipad.concat(str2binl(data)), 512 + data.length * chrsz);
 return core_md4(opad.concat(hash), 512 + 128);
}
/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */
function safe_add(x, y)
{
 var lsw = (x & 0xFFFF) + (y & 0xFFFF);
 var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
 return (msw << 16) | (lsw & 0xFFFF);
}
/*
 * Bitwise rotate a 32-bit number to the left.
 */
function rol(num, cnt)
{
 return (num << cnt) | (num >>> (32 - cnt));
}
/*
 * Convert a string to an array of little-endian words
 * If chrsz is ASCII, characters >255 have their hi-byte silently ignored.
 */
function str2binl(str)
{
 var bin = Array();
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < str.length * chrsz; i += chrsz)
  bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);
 return bin;
}
/*
 * Convert an array of little-endian words to a string
 */
function binl2str(bin)
{
 var str = "";
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < bin.length * 32; i += chrsz)
  str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);
 return str;
}
/*
 * Convert an array of little-endian words to a hex string.
 */
function binl2hex(binarray)
{
 var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i++)
 {
  str += hex_tab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +
      hex_tab.charAt((binarray[i>>2] >> ((i%4)*8 )) & 0xF);
 }
 return str;
}
/*
 * Convert an array of little-endian words to a base-64 string
 */
function binl2b64(binarray)
{
 var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i += 3)
 {
  var triplet = (((binarray[i  >> 2] >> 8 * ( i  %4)) & 0xFF) << 16)
        | (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )
        | ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);
  for(var j = 0; j < 4; j++)
  {
   if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
   else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
  }
 }
 return str;
}

SHA1算法

/*
 * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
 * in FIPS PUB 180-1
 * Version 2.1a Copyright Paul Johnston 2000 - 2002.
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for details.
 */
/*
 * Configurable variables. You may need to tweak these to be compatible with
 * the server-side, but the defaults work in most cases.
 */
var hexcase = 0; /* hex output format. 0 - lowercase; 1 - uppercase    */
var b64pad = ""; /* base-64 pad character. "=" for strict RFC compliance  */
var chrsz  = 8; /* bits per input character. 8 - ASCII; 16 - Unicode   */
/*
 * These are the functions you'll usually want to call
 * They take string arguments and return either hex or base-64 encoded strings
 */
function hex_sha1(s){return binb2hex(core_sha1(str2binb(s),s.length * chrsz));}
function b64_sha1(s){return binb2b64(core_sha1(str2binb(s),s.length * chrsz));}
function str_sha1(s){return binb2str(core_sha1(str2binb(s),s.length * chrsz));}
function hex_hmac_sha1(key, data){ return binb2hex(core_hmac_sha1(key, data));}
function b64_hmac_sha1(key, data){ return binb2b64(core_hmac_sha1(key, data));}
function str_hmac_sha1(key, data){ return binb2str(core_hmac_sha1(key, data));}
/*
 * Perform a simple self-test to see if the VM is working
 */
function sha1_vm_test()
{
 return hex_sha1("abc") == "a9993e364706816aba3e25717850c26c9cd0d89d";
}
/*
 * Calculate the SHA-1 of an array of big-endian words, and a bit length
 */
function core_sha1(x, len)
{
 /* append padding */
 x[len >> 5] |= 0x80 << (24 - len % 32);
 x[((len + 64 >> 9) << 4) + 15] = len;
 var w = Array(80);
 var a = 1732584193;
 var b = -271733879;
 var c = -1732584194;
 var d = 271733878;
 var e = -1009589776;
 for(var i = 0; i < x.length; i += 16)
 {
  var olda = a;
  var oldb = b;
  var oldc = c;
  var oldd = d;
  var olde = e;
  for(var j = 0; j < 80; j++)
  {
   if(j < 16) w[j] = x[i + j];
   else w[j] = rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
   var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)),
            safe_add(safe_add(e, w[j]), sha1_kt(j)));
   e = d;
   d = c;
   c = rol(b, 30);
   b = a;
   a = t;
  }
  a = safe_add(a, olda);
  b = safe_add(b, oldb);
  c = safe_add(c, oldc);
  d = safe_add(d, oldd);
  e = safe_add(e, olde);
 }
 return Array(a, b, c, d, e);
}
/*
 * Perform the appropriate triplet combination function for the current
 * iteration
 */
function sha1_ft(t, b, c, d)
{
 if(t < 20) return (b & c) | ((~b) & d);
 if(t < 40) return b ^ c ^ d;
 if(t < 60) return (b & c) | (b & d) | (c & d);
 return b ^ c ^ d;
}
/*
 * Determine the appropriate additive constant for the current iteration
 */
function sha1_kt(t)
{
 return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 :
     (t < 60) ? -1894007588 : -899497514;
}
/*
 * Calculate the HMAC-SHA1 of a key and some data
 */
function core_hmac_sha1(key, data)
{
 var bkey = str2binb(key);
 if(bkey.length > 16) bkey = core_sha1(bkey, key.length * chrsz);
 var ipad = Array(16), opad = Array(16);
 for(var i = 0; i < 16; i++)
 {
  ipad[i] = bkey[i] ^ 0x36363636;
  opad[i] = bkey[i] ^ 0x5C5C5C5C;
 }
 var hash = core_sha1(ipad.concat(str2binb(data)), 512 + data.length * chrsz);
 return core_sha1(opad.concat(hash), 512 + 160);
}
/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */
function safe_add(x, y)
{
 var lsw = (x & 0xFFFF) + (y & 0xFFFF);
 var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
 return (msw << 16) | (lsw & 0xFFFF);
}
/*
 * Bitwise rotate a 32-bit number to the left.
 */
function rol(num, cnt)
{
 return (num << cnt) | (num >>> (32 - cnt));
}
/*
 * Convert an 8-bit or 16-bit string to an array of big-endian words
 * In 8-bit function, characters >255 have their hi-byte silently ignored.
 */
function str2binb(str)
{
 var bin = Array();
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < str.length * chrsz; i += chrsz)
  bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (32 - chrsz - i%32);
 return bin;
}
/*
 * Convert an array of big-endian words to a string
 */
function binb2str(bin)
{
 var str = "";
 var mask = (1 << chrsz) - 1;
 for(var i = 0; i < bin.length * 32; i += chrsz)
  str += String.fromCharCode((bin[i>>5] >>> (32 - chrsz - i%32)) & mask);
 return str;
}
/*
 * Convert an array of big-endian words to a hex string.
 */
function binb2hex(binarray)
{
 var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i++)
 {
  str += hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +
      hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8 )) & 0xF);
 }
 return str;
}
/*
 * Convert an array of big-endian words to a base-64 string
 */
function binb2b64(binarray)
{
 var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 var str = "";
 for(var i = 0; i < binarray.length * 4; i += 3)
 {
  var triplet = (((binarray[i  >> 2] >> 8 * (3 - i  %4)) & 0xFF) << 16)
        | (((binarray[i+1 >> 2] >> 8 * (3 - (i+1)%4)) & 0xFF) << 8 )
        | ((binarray[i+2 >> 2] >> 8 * (3 - (i+2)%4)) & 0xFF);
  for(var j = 0; j < 4; j++)
  {
   if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
   else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
  }
 }
 return str;
}

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