/* A JavaScript implementation of the Secure Hash Algorithm, SHA-256
 * Version 0.3 Copyright Angel Marin 2003-2004 - http://anmar.eu.org/
 * Distributed under the BSD License
 * Some bits taken from Paul Johnston's SHA-1 implementation
 */

var chrsz=8
function safe_add(x,y){
var lsw=(x&0xFFFF)+(y&0xFFFF)
var msw=(x>>16)+(y>>16)+(lsw>>16)
return(msw<<16)|(lsw&0xFFFF)}
function S(X,n){return(X>>>n)|(X<<(32-n));}
function R(X,n){return(X>>>n);}
function Ch(x,y,z){return((x&y)^((~x)&z));}
function Maj(x,y,z){return((x&y)^(x&z)^(y&z));}
function Sigma0256(x){return(S(x,2)^ S(x,13)^ S(x,22));}
function Sigma1256(x){return(S(x,6)^ S(x,11)^ S(x,25));}
function Gamma0256(x){return(S(x,7)^ S(x,18)^ R(x,3));}
function Gamma1256(x){return(S(x,17)^ S(x,19)^ R(x,10));}
function core_sha256(m,l){
var K=new Array(0x428A2F98,0x71374491,0xB5C0FBCF,0xE9B5DBA5,0x3956C25B,0x59F111F1,0x923F82A4,0xAB1C5ED5,0xD807AA98,0x12835B01,0x243185BE,0x550C7DC3,0x72BE5D74,0x80DEB1FE,0x9BDC06A7,0xC19BF174,0xE49B69C1,0xEFBE4786,0xFC19DC6,0x240CA1CC,0x2DE92C6F,0x4A7484AA,0x5CB0A9DC,0x76F988DA,0x983E5152,0xA831C66D,0xB00327C8,0xBF597FC7,0xC6E00BF3,0xD5A79147,0x6CA6351,0x14292967,0x27B70A85,0x2E1B2138,0x4D2C6DFC,0x53380D13,0x650A7354,0x766A0ABB,0x81C2C92E,0x92722C85,0xA2BFE8A1,0xA81A664B,0xC24B8B70,0xC76C51A3,0xD192E819,0xD6990624,0xF40E3585,0x106AA070,0x19A4C116,0x1E376C08,0x2748774C,0x34B0BCB5,0x391C0CB3,0x4ED8AA4A,0x5B9CCA4F,0x682E6FF3,0x748F82EE,0x78A5636F,0x84C87814,0x8CC70208,0x90BEFFFA,0xA4506CEB,0xBEF9A3F7,0xC67178F2)
var HASH=new Array(0x6A09E667,0xBB67AE85,0x3C6EF372,0xA54FF53A,0x510E527F,0x9B05688C,0x1F83D9AB,0x5BE0CD19)
var W=new Array(64)
var a,b,c,d,e,f,g,h,i,j
var T1,T2
m[l>>5] |=0x80<<(24-l % 32)
m[((l+64>>9)<<4)+15]=l
for(var i=0;i<m.length;i+=16){
a=HASH[0];b=HASH[1];c=HASH[2];d=HASH[3];e=HASH[4];f=HASH[5];g=HASH[6];h=HASH[7]
for(var j=0;j<64;j++){
if(j<16)W[j]=m[j+i]
else W[j]=safe_add(safe_add(safe_add(Gamma1256(W[j-2]),W[j-7]),Gamma0256(W[j-15])),W[j-16])
T1=safe_add(safe_add(safe_add(safe_add(h,Sigma1256(e)),Ch(e,f,g)),K[j]),W[j])
T2=safe_add(Sigma0256(a),Maj(a,b,c))
h=g;g=f;f=e;e=safe_add(d,T1);d=c;c=b;b=a;a=safe_add(T1,T2)}
HASH[0]=safe_add(a,HASH[0]);HASH[1]=safe_add(b,HASH[1]);HASH[2]=safe_add(c,HASH[2]);HASH[3]=safe_add(d,HASH[3]);HASH[4]=safe_add(e,HASH[4]);HASH[5]=safe_add(f,HASH[5]);HASH[6]=safe_add(g,HASH[6]);HASH[7]=safe_add(h,HASH[7])}
return HASH}
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)<<(24-i%32)
return bin}
function binb2hex(binarray){
var hexcase=0
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}
function hex_sha256(s){return binb2hex(core_sha256(str2binb(s),s.length*chrsz));}