Digest::BubbleBabble − Create bubble−babble fingerprints


# Create a fingerprint of a simple string.
use Digest::BubbleBabble qw( bubblebabble );
my $fingerprint = bubblebabble( Digest => "Pineapple" );
# Create a fingerprint of a SHA−1 hash.
use Digest::SHA1 qw( sha1 );
$fingerprint = bubblebabble( Digest => sha1("hello") );


Digest::BubbleBabble takes a message digest (often generated by either of the MD5 or SHA−1 message digest algorithms) and creates a fingerprint of that digest in "bubble babble" format. Bubble babble is a method of representing a message digest as a string of "real" words, to make the fingerprint easier to remember. The "words" are not necessarily real words, but they look more like words than a string of hex characters.

Bubble babble fingerprinting is used by the SSH2 suite (and, consequently, by Net::SSH::Perl, the Perl SSH implementation) to display easy-to-remember key fingerprints. The key (a DSA or RSA key) is converted into a textual form, digested using Digest::SHA1, and run through bubblebabble to create the key fingerprint.


Digest::BubbleBabble conditionally exports one function called bubblebabble; to import the function you must choose to import it, like this:

use Digest::BubbleBabble qw( bubblebabble );

bubblebabble( Digest => $digest )
Currently takes only one pair of arguments, the key of which must be Digest, the value of which is the actual message digest $digest. You should generate this message digest yourself using either Digest::MD5 of Digest::SHA1.

Returns the bubble babble form of the digest.


The BubbleBabble specification is available at: http://web.mit.edu/kenta/www/one/bubblebabble/spec/jrtrjwzi/draft−huima−01.txt


Digest::BubbleBabble is free software; you may redistribute it and/or modify it under the same terms as Perl itself.


Benjamin Trott, cpan@stupidfool.org

Except where otherwise noted, Digest::BubbleBabble is Copyright 2001 Benjamin Trott. All rights reserved.