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- (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;
- })();
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