hylianshield/base32-crockford

Implementation of Crockford's Base 32 encoder and decoder

1.0.1 2017-01-28 21:12 UTC

Requires

• php: ^7.0
• hylianshield/alphabet: ^1.0

Requires (Dev)

• hylianshield/validator-base-encoding: ^2.0.3
• phpunit/phpunit: ^5.7.5

Apache-2.0

• Jan-Marten de Boer

README

This package holds an encoder / decoder that implements Crockford's Base 32 implementation.

Installation

composer require hylianshield/base32-crockford:^1.0

Specification

Attribute	Value
Padding	0 (required)
Partitioning	- (optional)

Usage

<?php
use HylianShield\Encoding\Base32CrockfordEncoder;

$encoder = new Base32CrockfordEncoder();

$encoded = $encoder->encode(1337);        // 0000019S5
$decoded = $encoder->decode('0000019S5'); // 1337

Limitations

While big numbers can be properly encoded, the built-in multiply operation for PHP fails to return the correct response if a number gets too high.

This can be solved by using BC Math, however, since that is not installed by default, this implementation has an upper-limit.

On the tested system, the upper limit lies between 18.014.398.509.481.982 and 36.028.797.018.963.966. Read: 18 quadrillion and 36 quadrillion respectively. This may differ when using a different CPU architecture.

See the example script to reproduce these findings. Or simply run:

composer example

Which outputs:

... previous rows ...
#2251799813685246 => 000001ZZ-ZZZZZZZYN => 2251799813685246
#4503599627370494 => 000003ZZ-ZZZZZZZY7 => 4503599627370494
#9007199254740990 => 000007ZZ-ZZZZZZZYG => 9007199254740990
#18014398509481982 => 00000FZZ-ZZZZZZZY$ => 18014398509481982
#36028797018963966 => 00001000-0000000Y~ => 
	Check symbol "~" (33) mismatches "10000000000Y" (36028797018963998).

One can see that the number on the left no longer matches the number on the right.