NAME¶
base32 - base32 standard encoding
SYNOPSIS¶
package require
Tcl 8.4
package require
base32::core ?0.1?
package require
base32 ?0.1?
::base32::encode string
::base32::decode estring
DESCRIPTION¶
This package provides commands for encoding and decoding of strings into and out
of the standard base32 encoding as specified in RFC 3548.
API¶
- ::base32::encode string
- This command encodes the given string in base32 and
returns the encoded string as its result. The result may be padded with
the character = to signal a partial encoding at the end of the
input string.
- ::base32::decode estring
- This commands takes the estring and decodes it under
the assumption that it is a valid base32 encoded string. The result of the
decoding is returned as the result of the command.
Note that while the encoder will generate only uppercase characters this
decoder accepts input in lowercase as well.
The command will always throw an error whenever encountering conditions
which signal some type of bogus input, namely if
- [1]
- the input contains characters which are not valid output of
a base32 encoder,
- [2]
- the length of the input is not a multiple of eight,
- [3]
- padding appears not at the end of input, but in the
middle,
- [4]
- the padding has not of length six, four, three, or one
characters,
CODE MAP¶
The code map used to convert 5-bit sequences is shown below, with the numeric id
of the bit sequences to the left and the character used to encode it to the
right. It should be noted that the characters "0" and "1"
are not used by the encoding. This is done as these characters can be easily
confused with "O", "o" and "l" (L).
0 A 9 J 18 S 27 3
1 B 10 K 19 T 28 4
2 C 11 L 20 U 29 5
3 D 12 M 21 V 30 6
4 E 13 N 22 W 31 7
5 F 14 O 23 X
6 G 15 P 24 Y
7 H 16 Q 25 Z
8 I 17 R 26 2
BUGS, IDEAS, FEEDBACK¶
This document, and the package it describes, will undoubtedly contain bugs and
other problems. Please report such in the category
base32 of the
Tcllib SF Trackers [
http://sourceforge.net/tracker/?group_id=12883].
Please also report any ideas for enhancements you may have for either package
and/or documentation.
KEYWORDS¶
base32, rfc3548
CATEGORY¶
Text processing
COPYRIGHT¶
Copyright (c) Public domain