From 1d26ab1de6ee514cd836eb6b181a0b38614afffc Mon Sep 17 00:00:00 2001
From: milkbone57 <milkbone57>
Date: Sun, 13 Jul 2003 05:44:00 +0000
Subject: [PATCH] *** empty log message ***
---
plugins/Tk-Logon/Crypt/Solitaire.pm | 192 ++++++++++++++++++++++++++++
1 file changed, 192 insertions(+)
create mode 100644 plugins/Tk-Logon/Crypt/Solitaire.pm
diff --git a/plugins/Tk-Logon/Crypt/Solitaire.pm b/plugins/Tk-Logon/Crypt/Solitaire.pm
new file mode 100644
index 0000000..99cac4c
--- /dev/null
+++ b/plugins/Tk-Logon/Crypt/Solitaire.pm
@@ -0,0 +1,192 @@
+#------------------------------------------------------------------------------#
+# Crypt::Solitaire
+#
+# Solitaire cryptosystem, as used in Neal Stephenson's novel _Cryptonomicon_
+# Designed by Bruce Schneier (President, Counterpane Systems)
+# Original Perl Code by Ian Goldberg <ian@cypherpunks.ca>, 19980817
+# Minor changes and module-ification by Kurt Kincaid <sifukurt@yahoo.com>
+#
+# Last Modified: 28-Nov-2001 04:20:10 PM
+# Copyright(c) 2001, Kurt Kincaid. All Rights Reserved.
+#
+# This is free software and may be modified and/or redistributed under the
+# same terms as perl itself.
+#------------------------------------------------------------------------------#
+
+package Crypt::Solitaire;
+use strict;
+use vars qw($VERSION @ISA @EXPORT @EXPORT_OK $multFactor $k $D $c $v $Deck $text $passphrase $mode $class );
+
+require Exporter;
+
+@ISA = qw(Exporter AutoLoader);
+@EXPORT_OK = qw(Pontifex);
+
+$VERSION = "2.0";
+
+sub new {
+ ( $class, $passphrase ) = @_;
+ $passphrase =~ y/a-z/A-Z/;
+ $passphrase =~ s/[A-Z]/$k=ord($&)-64,&e/eg;
+ my $self = bless {}, $class;
+ return $self;
+}
+
+sub encrypt {
+ my $self = shift;
+ ( $text, $passphrase ) = @_;
+ return Pontifex( $text, $passphrase, "e" );
+}
+
+sub decrypt {
+ my $self = shift;
+ ( $text, $passphrase ) = @_;
+ return Pontifex( $text, $passphrase, "d" );
+}
+
+sub Pontifex {
+ if ( ref $_[ 0 ] ) {
+ my $self = shift;
+ }
+ ( $text, $passphrase, $mode ) = @_;
+ if ( $mode =~ /^e/i ) {
+ $multFactor = 1;
+ } elsif ( $mode =~ /^d/i ) {
+ $multFactor = -1;
+ } else {
+ return undef;
+ }
+
+ $Deck = pack( 'C*', 33 .. 86 );
+
+ $k = 0;
+
+ $text =~ y/a-z/A-Z/;
+ $text =~ y/A-Z//dc;
+ if ( $multFactor == 1 ) {
+ $text .= "X" while length( $text ) % 5;
+ }
+ $text =~ s/./chr((ord($&)-13+$multFactor*&e)%26+65)/eg;
+
+ if ( $multFactor == -1 ) {
+ $text =~ s/X*$//;
+ }
+ $text =~ s/.{5}/$& /g;
+ return $text;
+}
+
+sub v {
+ $v = ord( substr( $D, $_[ 0 ] ) ) - 32;
+ $v > 53 ? 53 : $v;
+}
+
+sub e {
+ $D =~ s/(.*)U$/U$1/;
+ $D =~ s/U(.)/$1U/;
+
+ $D =~ s/(.*)V$/V$1/;
+ $D =~ s/V(.)/$1V/;
+ $D =~ s/(.*)V$/V$1/;
+ $D =~ s/V(.)/$1V/;
+
+ $D =~ s/(.*)([UV].*[UV])(.*)/$3$2$1/;
+
+ $c = &v( 53 );
+ $D =~ s/(.{$c})(.*)(.)/$2$1$3/;
+
+ if ( $k ) {
+ $D =~ s/(.{$k})(.*)(.)/$2$1$3/;
+ return;
+ }
+
+ $c = &v( &v( 0 ) );
+
+ $c > 52 ? &e : $c;
+}
+
+1;
+__END__
+
+
+=head1 NAME
+
+Crypt::Solitaire - Solitaire encryption
+
+=head1 SYNOPSIS
+
+# OO Interface
+ use Crypt::Solitaire;
+ $ref = Crypt::Solitaire->new( $passphrase );
+ $encrypted = $ref->encrypt( $text );
+
+ $ref2 = Crypt::Solitaire->new( $passphrase );
+ $decrypted = $ref2->decrypt( $encrypted );
+
+# Functional Interface
+
+ use Crypt::Solitaire;
+ my $encrypted = Pontifex( $plaintext, $passphrase, $mode );
+
+=head1 DESCRIPTION
+
+Solitaire is a top-notch pencil-and-paper encryption system developed by Bruce Schneier.
+Here is the description in Schneier's own words:
+
+"In Neal Stephenson's novel Cryptonomicon, the character Enoch Root describes a
+cryptosystem code-named "Pontifex" to another character named Randy Waterhouse, and later
+reveals that the steps of the algorithm are intended to be carried out using a deck of
+playing cards. These two characters go on to exchange several encrypted messages using
+this system. The system is called "Solitaire" (in the novel, "Pontifex" is a code name
+intended to temporarily conceal the fact that it employs a deck of cards) and I designed
+it to allow field agents to communicate securely without having to rely on electronics or
+having to carry incriminating tools. An agent might be in a situation where he just does
+not have access to a computer, or may be prosecuted if he has tools for secret
+communication. But a deck of cards...what harm is that?
+
+"Solitaire gets its security from the inherent randomness in a shuffled deck of cards. By
+manipulating this deck, a communicant can create a string of "random" letters that he
+then combines with his message. Of course Solitaire can be simulated on a computer, but
+it is designed to be implemented by hand.
+
+"Solitaire may be low-tech, but its security is intended to be high-tech. I designed
+Solitaire to be secure even against the most well-funded military adversaries with the
+biggest computers and the smartest cryptanalysts. Of course, there is no guarantee that
+someone won't find a clever attack against Solitaire, but the algorithm is certainly
+better than any other pencil-and-paper cipher I've ever seen."
+
+Simple system, easy to use, and relatively fast.
+
+=head1 LIMITATIONS
+
+Restricted only to letters A..Z. Lower case letters are converted to upper
+case, and due to the fact that Solitaire applies its own formatting to the text, the
+output can be a little tricky at first glance.
+
+It also should be noted that there is a verified bias in the algorithm. Fore more
+information on this, go here: http://www.ciphergoth.org/crypto/solitaire/
+
+=head1 METHODS
+
+=over 4
+
+=item B<Pontifex> $text, $passphrase, $mode
+
+$text is encrypted using $passphrase. Encrypts or decrypts, based on $mode. Mode must
+be set to "e" or "d," for encrypting and decrypting, respectively.
+
+=back
+
+=head1 AUTHOR
+
+Designed by Bruce Schneier (President, Counterpane Systems)
+
+Original Perl Code by Ian Goldberg <ian@cypherpunks.ca>, 19980817
+
+Minor changes and module-ification by Kurt Kincaid <sifukurt@yahoo.com>
+
+=head1 SEE ALSO
+
+perl(1), Counterpane System (http://www.counterpane.com).
+
+=cut
+