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@Seldaek
Created February 3, 2012 13:37
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SHA1 + HMAC in JS
var Crypto = {};
Crypto.sha1_hmac = function (msg, key) {
"use strict";
var oKeyPad, iKeyPad, iPadRes, bytes, i, len;
if (key.length > 64) {
// keys longer than blocksize are shortened
key = Crypto.sha1(key, true);
}
bytes = [];
len = key.length;
for (i = 0; i < 64; ++i) {
bytes[i] = len > i ? key.charCodeAt(i) : 0x00;
}
oKeyPad = "";
iKeyPad = "";
for (i = 0; i < 64; ++i) {
oKeyPad += String.fromCharCode(bytes[i] ^ 0x5C);
iKeyPad += String.fromCharCode(bytes[i] ^ 0x36);
}
iPadRes = Crypto.sha1(iKeyPad + msg, true);
return Crypto.sha1(oKeyPad + iPadRes);
};
Crypto.sha1 = function (msg, raw) {
function rotate_left(n,s) {
var t4 = ( n<<s ) | (n>>>(32-s));
return t4;
}
function lsb_hex(val) {
var str="";
var i;
var vh;
var vl;
for( i=0; i<=6; i+=2 ) {
vh = (val>>>(i*4+4))&0x0f;
vl = (val>>>(i*4))&0x0f;
str += vh.toString(16) + vl.toString(16);
}
return str;
}
function cvt_hex(val, raw) {
var str="";
var i;
var v;
for( i=7; i>=0; i-- ) {
v = (val>>>(i*4))&0x0f;
str += raw ? String.fromCharCode(v) : v.toString(16);
}
return str;
}
var blockstart;
var i, j;
var W = new Array(80);
var H0 = 0x67452301;
var H1 = 0xEFCDAB89;
var H2 = 0x98BADCFE;
var H3 = 0x10325476;
var H4 = 0xC3D2E1F0;
var A, B, C, D, E;
var result, rawResult;
var msg_len = msg.length;
var word_array = [];
for( i=0; i<msg_len-3; i+=4 ) {
j = msg.charCodeAt(i)<<24 | msg.charCodeAt(i+1)<<16 |
msg.charCodeAt(i+2)<<8 | msg.charCodeAt(i+3);
word_array.push( j );
}
switch( msg_len % 4 ) {
case 0:
i = 0x080000000;
break;
case 1:
i = msg.charCodeAt(msg_len-1)<<24 | 0x0800000;
break;
case 2:
i = msg.charCodeAt(msg_len-2)<<24 | msg.charCodeAt(msg_len-1)<<16 | 0x08000;
break;
case 3:
i = msg.charCodeAt(msg_len-3)<<24 | msg.charCodeAt(msg_len-2)<<16 | msg.charCodeAt(msg_len-1)<<8 | 0x80;
break;
}
word_array.push( i );
while( (word_array.length % 16) != 14 ) word_array.push( 0 );
word_array.push( msg_len>>>29 );
word_array.push( (msg_len<<3)&0x0ffffffff );
for ( blockstart=0; blockstart<word_array.length; blockstart+=16 ) {
for( i=0; i<16; i++ ) W[i] = word_array[blockstart+i];
for( i=16; i<=79; i++ ) W[i] = rotate_left(W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16], 1);
A = H0;
B = H1;
C = H2;
D = H3;
E = H4;
for( i= 0; i<=19; i++ ) {
temp = (rotate_left(A,5) + ((B&C) | (~B&D)) + E + W[i] + 0x5A827999) & 0x0ffffffff;
E = D;
D = C;
C = rotate_left(B,30);
B = A;
A = temp;
}
for( i=20; i<=39; i++ ) {
temp = (rotate_left(A,5) + (B ^ C ^ D) + E + W[i] + 0x6ED9EBA1) & 0x0ffffffff;
E = D;
D = C;
C = rotate_left(B,30);
B = A;
A = temp;
}
for( i=40; i<=59; i++ ) {
temp = (rotate_left(A,5) + ((B&C) | (B&D) | (C&D)) + E + W[i] + 0x8F1BBCDC) & 0x0ffffffff;
E = D;
D = C;
C = rotate_left(B,30);
B = A;
A = temp;
}
for( i=60; i<=79; i++ ) {
temp = (rotate_left(A,5) + (B ^ C ^ D) + E + W[i] + 0xCA62C1D6) & 0x0ffffffff;
E = D;
D = C;
C = rotate_left(B,30);
B = A;
A = temp;
}
H0 = (H0 + A) & 0x0ffffffff;
H1 = (H1 + B) & 0x0ffffffff;
H2 = (H2 + C) & 0x0ffffffff;
H3 = (H3 + D) & 0x0ffffffff;
H4 = (H4 + E) & 0x0ffffffff;
}
result = (cvt_hex(H0) + cvt_hex(H1) + cvt_hex(H2) + cvt_hex(H3) + cvt_hex(H4)).toLowerCase();
if (!raw) {
return result;
}
rawResult = "";
while (result.length) {
rawResult += String.fromCharCode(parseInt(result.substr(0, 2), 16));
result = result.substr(2);
}
return rawResult;
};
@vaibhavr2709
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can u pls tell me the syntax to call the sha1_hmac function

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ghost commented Jan 13, 2020

can u pls tell me the syntax to call the sha1_hmac function

1 year but if other need help:
Crypto.sha1_hmac("your input","your key")

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