js-encrypt/bin/lib/jsbn/base64.js

A Javascript library to perform OpenSSL RSA Encryption, Decryption, and Key Generation.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.hex2b64 = hex2b64;
exports.b64tohex = b64tohex;
exports.b64toBA = b64toBA;

var _jsbn = require("./jsbn");

var b64map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var b64pad = "=";

function hex2b64(h) {
  var i;
  var c;
  var ret = "";
  for (i = 0; i + 3 <= h.length; i += 3) {
    c = parseInt(h.substring(i, i + 3), 16);
    ret += b64map.charAt(c >> 6) + b64map.charAt(c & 63);
  }
  if (i + 1 == h.length) {
    c = parseInt(h.substring(i, i + 1), 16);
    ret += b64map.charAt(c << 2);
  } else if (i + 2 == h.length) {
    c = parseInt(h.substring(i, i + 2), 16);
    ret += b64map.charAt(c >> 2) + b64map.charAt((c & 3) << 4);
  }
  while ((ret.length & 3) > 0) {
    ret += b64pad;
  }return ret;
}

// convert a base64 string to hex
function b64tohex(s) {
  var ret = "";
  var i;
  var k = 0; // b64 state, 0-3
  var slop;
  for (i = 0; i < s.length; ++i) {
    if (s.charAt(i) == b64pad) break;
    var v = b64map.indexOf(s.charAt(i));
    if (v < 0) continue;
    if (k == 0) {
      ret += (0, _jsbn.int2char)(v >> 2);
      slop = v & 3;
      k = 1;
    } else if (k == 1) {
      ret += (0, _jsbn.int2char)(slop << 2 | v >> 4);
      slop = v & 0xf;
      k = 2;
    } else if (k == 2) {
      ret += (0, _jsbn.int2char)(slop);
      ret += (0, _jsbn.int2char)(v >> 2);
      slop = v & 3;
      k = 3;
    } else {
      ret += (0, _jsbn.int2char)(slop << 2 | v >> 4);
      ret += (0, _jsbn.int2char)(v & 0xf);
      k = 0;
    }
  }
  if (k == 1) ret += (0, _jsbn.int2char)(slop << 2);
  return ret;
}

// convert a base64 string to a byte/number array
function b64toBA(s) {
  //piggyback on b64tohex for now, optimize later
  var h = b64tohex(s);
  var i;
  var a = [];
  for (i = 0; 2 * i < h.length; ++i) {
    a[i] = parseInt(h.substring(2 * i, 2 * i + 2), 16);
  }
  return a;
}