Here's a quick sample of how to do bitwise encoding in javascript:
  2. var Encryption = (function() {
  4. function generateKey(seed) {
  5. var key = ""
  6. while (key.length < seed) key += Math.srand(seed)
  7. return key
  8. }
  10. /*
  11. * @param 'val' - a String to encode or a byte[] to decode.
  12. * @param 'salt' - (Optional) salt to perform bitwise encode/decode operation.
  13. */
  14. function xorHash(val, salt) {
  15. var encrypt = typeof val == 'string'
  16. var byteArr = encrypt ? val.toByteArr() : val
  17. var keyBytes = typeof salt == 'undefined' ?
  18. generateKey(byteArr.length).toByteArr() : salt.toByteArr()
  19. for (var i = 0; i < byteArr.length; i++) {
  20. byteArr[i] = byteArr[i] ^ keyBytes[i % keyBytes.length]
  21. }
  22. return (encrypt ? byteArr : String.fromCharCode.apply(String, byteArr))
  23. }
  25. return {
  26. /**
  27. *
  28. */
  29. encode : function(str, salt) {
  30. var encoded = []
  31. var bytes = xorHash(str, salt)
  32. for (var i = 0; i < bytes.length; i++) encoded.push(bytes[i].toString(16))
  33. return encoded.join(",")
  34. },
  35. /**
  36. *
  37. */
  38. decode : function(hsh, salt) {
  39. var decoded = []
  40. var hshArr = hsh.split(",")
  41. for (var i = 0; i < hshArr.length; i++) decoded.push(parseInt(hshArr[i], 16))
  42. return xorHash(decoded, salt)
  43. }
  44. }
  45. })()
  47. Math.srand = function(seed) {
  48. if (!seed) seed = new Date().getTime()
  49. seed = (seed*9301+49297) % 233280
  50. return seed/(233280.0)
  51. }
  53. String.prototype.toByteArr = function() {
  54. var arr = []
  55. for (var i = 0;i < this.length; i++) arr.push(this.charCodeAt(i))
  56. return arr
  57. }