Skip to content
This repository has been archived by the owner on Mar 13, 2023. It is now read-only.
/ pseudohash Public archive

Short, reversable, alphanumeric pseudohash with hard-to-guess sequence.

License

Notifications You must be signed in to change notification settings

CliffS/pseudohash

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

8 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

Pseudohash

Short, reversable, alphanumeric pseudo-hash with hard-to-guess sequence.

This is designed to generate a string from a number so that it can be displayed to a user without similar numbers being easy to guess. It is generally used in creating URLs that map to IDs.

This code was ported from my Perl module at https://github.com/CliffS/crypt-pseudo. The code was originally ported from the PHP at http://blog.kevburnsjr.com/php-unique-hash (now defunct).

Install

npm install pseudohash

Usage

assert = require('assert');
Pseudo = require('pseudohash');
var pseudo = new Pseudo(62);

var number = Math.floor(Math.random() * 100000);
var hash = pseudo.hash(number, 5);
console.log(hash);

var newnum = pseudo.unhash(hash);
assert.equal(newnum, number);

The new Pseudo() command creates a "factory" for generating pseudo-hashes. Yuo can choose between 62 bit hashes (using A to Z, a to z, 0 to 9) and 36 bit hashes (using upper-case letters and digits only). It defaults to 62 bits if no value is passed.

The hash() routine can be passed a length. This is the length of the resulting pseudo-hash, defaulting to 5.

The precision depends on the number of bits and the length of the pseudo-hash.

Using the defaults of 62 bits and a string length of 5, the maximum number that can be encrypted is 916,132,831.

With 32 bits (lower case only) the maximum for 5 characters is 60,466,175.

With 32 bits and a 6 character string, the maximum is 2,176,782,335.

Please let me know if you find this useful. Any issues or comments would be appreciated at Github.

About

Short, reversable, alphanumeric pseudohash with hard-to-guess sequence.

Resources

License

Stars

Watchers

Forks

Packages

No packages published