how to encrypt data using sha1

[netcracker]

Hi there!I've been looking on the allmighty internet for a way to encrypt some data using sha1 algorithm. I have to use HMAC_SHA1 and nothing else! The thing is that most of what I have found were using JavaScript and the key is written in the js file in plain text. I find this quite vulnerable and I would like to use something more secure. Something that would encrypt the data using my SHA1 key on the server - serverside.Does anyone know an ASP script that does this?I'm so totally lost right now, please help!THX

[justsomeguy]

SHA-1 doesn't use a key, and cannot be de-crypted. But, regardless, here is a Javascript implementation of the SHA-1 algorithm you can use in ASP:

<%/* * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined * in FIPS PUB 180-1 * Version 2.1 Copyright Paul Johnston 2000 - 2002. * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet * Distributed under the BSD License * See [url="http://pajhome.org.uk/crypt/md5"]http://pajhome.org.uk/crypt/md5[/url] 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) | ((~ & 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) << (24 - 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] >>> (24 - 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;}%>

You include that file and use it like this in your ASP code:hex_sha1("your string to encrypt");And again, SHA-1 does not use any sort of key, it only uses some bitshifting and things like that to do the encryption.I just noticed that you are specifying HMAC, which I wasn't aware of, and which does use a key. That implementation I posted also has HMAC functions that take a key as a parameter. I use this code server-side, it would probably work client-side as well, but I use it for server-side ASP stuff. Since it's server-side, the key doesn't need to be exposed to the client at all, you can put it wherever you want it.

[netcracker]

txh alot!I was aware of http://pajhome.org.uk/crypt/md5 but wanted to check for other opinions.I think I'll stick with this one since it's the best regarded... txh again!