mirror of https://github.com/1disk/edp445.git
97 lines
2.9 KiB
JavaScript
97 lines
2.9 KiB
JavaScript
(function() {
|
|
var base64map
|
|
= 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/',
|
|
|
|
crypt = {
|
|
// Bit-wise rotation left
|
|
rotl: function(n, b) {
|
|
return (n << b) | (n >>> (32 - b));
|
|
},
|
|
|
|
// Bit-wise rotation right
|
|
rotr: function(n, b) {
|
|
return (n << (32 - b)) | (n >>> b);
|
|
},
|
|
|
|
// Swap big-endian to little-endian and vice versa
|
|
endian: function(n) {
|
|
// If number given, swap endian
|
|
if (n.constructor == Number) {
|
|
return crypt.rotl(n, 8) & 0x00FF00FF | crypt.rotl(n, 24) & 0xFF00FF00;
|
|
}
|
|
|
|
// Else, assume array and swap all items
|
|
for (var i = 0; i < n.length; i++)
|
|
n[i] = crypt.endian(n[i]);
|
|
return n;
|
|
},
|
|
|
|
// Generate an array of any length of random bytes
|
|
randomBytes: function(n) {
|
|
for (var bytes = []; n > 0; n--)
|
|
bytes.push(Math.floor(Math.random() * 256));
|
|
return bytes;
|
|
},
|
|
|
|
// Convert a byte array to big-endian 32-bit words
|
|
bytesToWords: function(bytes) {
|
|
for (var words = [], i = 0, b = 0; i < bytes.length; i++, b += 8)
|
|
words[b >>> 5] |= bytes[i] << (24 - b % 32);
|
|
return words;
|
|
},
|
|
|
|
// Convert big-endian 32-bit words to a byte array
|
|
wordsToBytes: function(words) {
|
|
for (var bytes = [], b = 0; b < words.length * 32; b += 8)
|
|
bytes.push((words[b >>> 5] >>> (24 - b % 32)) & 0xFF);
|
|
return bytes;
|
|
},
|
|
|
|
// Convert a byte array to a hex string
|
|
bytesToHex: function(bytes) {
|
|
for (var hex = [], i = 0; i < bytes.length; i++) {
|
|
hex.push((bytes[i] >>> 4).toString(16));
|
|
hex.push((bytes[i] & 0xF).toString(16));
|
|
}
|
|
return hex.join('');
|
|
},
|
|
|
|
// Convert a hex string to a byte array
|
|
hexToBytes: function(hex) {
|
|
for (var bytes = [], c = 0; c < hex.length; c += 2)
|
|
bytes.push(parseInt(hex.substr(c, 2), 16));
|
|
return bytes;
|
|
},
|
|
|
|
// Convert a byte array to a base-64 string
|
|
bytesToBase64: function(bytes) {
|
|
for (var base64 = [], i = 0; i < bytes.length; i += 3) {
|
|
var triplet = (bytes[i] << 16) | (bytes[i + 1] << 8) | bytes[i + 2];
|
|
for (var j = 0; j < 4; j++)
|
|
if (i * 8 + j * 6 <= bytes.length * 8)
|
|
base64.push(base64map.charAt((triplet >>> 6 * (3 - j)) & 0x3F));
|
|
else
|
|
base64.push('=');
|
|
}
|
|
return base64.join('');
|
|
},
|
|
|
|
// Convert a base-64 string to a byte array
|
|
base64ToBytes: function(base64) {
|
|
// Remove non-base-64 characters
|
|
base64 = base64.replace(/[^A-Z0-9+\/]/ig, '');
|
|
|
|
for (var bytes = [], i = 0, imod4 = 0; i < base64.length;
|
|
imod4 = ++i % 4) {
|
|
if (imod4 == 0) continue;
|
|
bytes.push(((base64map.indexOf(base64.charAt(i - 1))
|
|
& (Math.pow(2, -2 * imod4 + 8) - 1)) << (imod4 * 2))
|
|
| (base64map.indexOf(base64.charAt(i)) >>> (6 - imod4 * 2)));
|
|
}
|
|
return bytes;
|
|
}
|
|
};
|
|
|
|
module.exports = crypt;
|
|
})();
|