JavaScript SHA1加密算法實現詳細代碼

fdpg 9年前發布 | 2K 次閱讀 JavaScript
/*

A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
in FIPS 180-1
Version 2.2 Copyright Paul Johnston 2000 - 2009.
Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
Distributed under the BSD License
See http://pajhome.org.uk/crypt/md5 for details.
http://www.sharejs.com
*/

/*

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   */

/*

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 rstr2hex(rstr_sha1(str2rstr_utf8(s))); }
function b64_sha1(s)    { return rstr2b64(rstr_sha1(str2rstr_utf8(s))); }
function any_sha1(s, e) { return rstr2any(rstr_sha1(str2rstr_utf8(s)), e); }
function hex_hmac_sha1(k, d)
{ return rstr2hex(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d))); }
function b64_hmac_sha1(k, d)
{ return rstr2b64(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d))); }
function any_hmac_sha1(k, d, e)
{ return rstr2any(rstr_hmac_sha1(str2rstr_utf8(k), str2rstr_utf8(d)), e); }

/*

Perform a simple self-test to see if the VM is working
*/
function sha1_vm_test()
{
return hex_sha1("abc").toLowerCase() == "a9993e364706816aba3e25717850c26c9cd0d89d";
}

/*

Calculate the SHA1 of a raw string
/
function rstr_sha1(s)
{
return binb2rstr(binb_sha1(rstr2binb(s), s.length  8));
}

/*

Calculate the HMAC-SHA1 of a key and some data (raw strings)
/
function rstr_hmac_sha1(key, data)
{
var bkey = rstr2binb(key);
if(bkey.length > 16) bkey = binb_sha1(bkey, key.length  8);
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 = binb_sha1(ipad.concat(rstr2binb(data)), 512 + data.length * 8);
return binb2rstr(binb_sha1(opad.concat(hash), 512 + 160));
}


/*

Convert a raw string to a hex string
*/
function rstr2hex(input)
{
try { hexcase } catch(e) { hexcase=0; }
var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
var output = "";
var x;
for(var i = 0; i < input.length; i++)
{
 x = input.charCodeAt(i);
 output += hex_tab.charAt((x >>> 4) & 0x0F)
    +  hex_tab.charAt( x        & 0x0F);

}
return output;
}

/*

Convert a raw string to a base-64 string
*/
function rstr2b64(input)
{
try { b64pad } catch(e) { b64pad=''; }
var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var output = "";
var len = input.length;
for(var i = 0; i < len; i += 3)
{
 var triplet = (input.charCodeAt(i) << 16)
         | (i + 1 < len ? input.charCodeAt(i+1) << 8 : 0)
         | (i + 2 < len ? input.charCodeAt(i+2)      : 0);

 for(var j = 0; j < 4; j++)
 {
   if(i  8 + j  6 > input.length  8) output += b64pad;
   else output += tab.charAt((triplet >>> 6(3-j)) & 0x3F);
 }
}
return output;
}

/*

Convert a raw string to an arbitrary string encoding
*/
function rstr2any(input, encoding)
{
var divisor = encoding.length;
var remainders = Array();
var i, q, x, quotient;
/ Convert to an array of 16-bit big-endian values, forming the dividend /
var dividend = Array(Math.ceil(input.length / 2));
for(i = 0; i < dividend.length; i++)
{
 dividend[i] = (input.charCodeAt(i  2) << 8) | input.charCodeAt(i  2 + 1);
}
/*

Repeatedly perform a long division. The binary array forms the dividend,
the length of the encoding is the divisor. Once computed, the quotient
forms the dividend for the next step. We stop when the dividend is zero.
All remainders are stored for later use.
/
while(dividend.length > 0)
{
quotient = Array();
x = 0;
for(i = 0; i < dividend.length; i++)
{
 x = (x << 16) + dividend[i];
 q = Math.floor(x / divisor);
 x -= q  divisor;
 if(quotient.length > 0 || q > 0)
   quotient[quotient.length] = q;
}
remainders[remainders.length] = x;
dividend = quotient;
}

/ Convert the remainders to the output string /
var output = "";
for(i = remainders.length - 1; i >= 0; i--)
 output += encoding.charAt(remainders[i]);
/ Append leading zero equivalents /
var full_length = Math.ceil(input.length * 8 /

                             (Math.log(encoding.length) / Math.log(2)))

for(i = output.length; i < full_length; i++)
 output = encoding[0] + output;
return output;
}


/*

Encode a string as utf-8.
For efficiency, this assumes the input is valid utf-16.
*/
function str2rstr_utf8(input)
{
var output = "";
var i = -1;
var x, y;
while(++i < input.length)
{
 / Decode utf-16 surrogate pairs /
 x = input.charCodeAt(i);
 y = i + 1 < input.length ? input.charCodeAt(i + 1) : 0;
 if(0xD800 <= x && x <= 0xDBFF && 0xDC00 <= y && y <= 0xDFFF)
 {
   x = 0x10000 + ((x & 0x03FF) << 10) + (y & 0x03FF);
   i++;
 }
/ Encode output as utf-8 /
 if(x <= 0x7F)
   output += String.fromCharCode(x);
 else if(x <= 0x7FF)
   output += String.fromCharCode(0xC0 | ((x >>> 6 ) & 0x1F),

                             0x80 | ( x         & 0x3F));

else if(x <= 0xFFFF)
   output += String.fromCharCode(0xE0 | ((x >>> 12) & 0x0F),

                             0x80 | ((x >>> 6 ) & 0x3F),
                             0x80 | ( x         & 0x3F));

else if(x <= 0x1FFFFF)
   output += String.fromCharCode(0xF0 | ((x >>> 18) & 0x07),

                             0x80 | ((x >>> 12) & 0x3F),
                             0x80 | ((x >>> 6 ) & 0x3F),
                             0x80 | ( x         & 0x3F));

}
return output;
}


/*

Encode a string as utf-16
*/
function str2rstr_utf16le(input)
{
var output = "";
for(var i = 0; i < input.length; i++)
 output += String.fromCharCode( input.charCodeAt(i)        & 0xFF,
                           (input.charCodeAt(i) >>> 8) & 0xFF);

return output;
}

function str2rstr_utf16be(input)
{
  var output = "";
  for(var i = 0; i < input.length; i++)
    output += String.fromCharCode((input.charCodeAt(i) >>> 8) & 0xFF,
                                   input.charCodeAt(i)        & 0xFF);
  return output;
}
/*

Convert a raw string to an array of big-endian words
Characters >255 have their high-byte silently ignored.
/
function rstr2binb(input)
{
var output = Array(input.length >> 2);
for(var i = 0; i < output.length; i++)
 output[i] = 0;
for(var i = 0; i < input.length  8; i += 8)
 output[i>>5] |= (input.charCodeAt(i / 8) & 0xFF) << (24 - i % 32);
return output;
}

/*

Convert an array of big-endian words to a string
/
function binb2rstr(input)
{
var output = "";
for(var i = 0; i < input.length  32; i += 8)
 output += String.fromCharCode((input[i>>5] >>> (24 - i % 32)) & 0xFF);
return output;
}

/*

Calculate the SHA-1 of an array of big-endian words, and a bit length
/
function binb_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] = bit_rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
   var t = safe_add(safe_add(bit_rol(a, 5), sha1_ft(j, b, c, d)),

                safe_add(safe_add(e, w[j]), sha1_kt(j)));

e = d;
   d = c;
   c = bit_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;

}

/*

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));
}
</pre>
本文由用戶 fdpg 自行上傳分享，僅供網友學習交流。所有權歸原作者，若您的權利被侵害，請聯系管理員。
轉載本站原創文章，請注明出處，并保留原始鏈接、圖片水印。
本站是一個以用戶分享為主的開源技術平臺，歡迎各類分享！
本文地址：http://www.baiduhome.net/code/view/1428130688240
JavaScript
JavaScript SHA1加密算法實現詳細代碼

相關代碼

相關文檔

相關經驗

目錄
