#!perl
#########################################################################
#        This Perl script is Copyright (c) 2000, Peter J Billam         #
#               c/o P J B Computing, www.pjb.com.au                     #
#                                                                       #
#     This program is free software; you can redistribute it and/or     #
#            modify it under the same terms as Perl itself.             #
#########################################################################
use Crypt::Tea;

while ($ARGV[$[] =~ /^-/) {
	if ($ARGV[$[] =~ /^-c/)      { $encrypt='yes'; shift;
	} elsif ($ARGV[$[] =~ /^-s/) { $sign='yes'; shift;
	} elsif ($ARGV[$[] =~ /^-j/) { print &tea_in_javascript;  exit 1;
	} else { print <<EOT; exit;
usage:
   tea -c filename   # encrypts filename
   tea filename      # decrypts filename
   tea -s filename   # calculates ascii digital signature for filename
   tea -j            # outputs JavaScript code to do compatible encryption
   tea -h            # prints this message

For encryption and decryption, you will be asked for a password.
It should be a sufficiently longish string; say 17 random 8-bit bytes.
Version ${Crypt::Tea::VERSION},
#COMMENT#

EOT
	}
}
#    tea -c3 filename  # triple-encrypts filename
#    tea -3 filename   # triple-decrypts filename
# for single encryption, or 3 times that to justify triple encryption.

undef $/; my $text = <>; $/="\n";
if ($sign) { print &asciidigest ($text) . "\n"; exit 0; }

open(TTY,  ">/dev/tty")  || die "Can't write /dev/tty: $!\n";
open(TTYIN, "</dev/tty") || die "Can't read /dev/tty: $!\n";
print TTY 'Password: '; my $key = <TTYIN>;
close TTY; close TTYIN;
$key =~ s/[\r\n]*$//;
exit unless $key;

if ($encrypt) {
	print &encrypt ($text, $key), "\n";
} else {
	print &decrypt ($text, $key);
}
exit 0;

__END__

=pod

=head1 NAME

tea - Perl script to give command-line access to Crypt::Tea.pm

=head1 SYNOPSIS

  tea -c filename   # encrypts filename
  tea filename      # decrypts filename
  tea -s filename   # calculates ascii digital signature for filename
  tea -j            # outputs JavaScript doing compatible encryption
  tea -h            # prints this message
  ps axww | tea -s  # have the best password in town !

For encryption and decryption, you will be asked for a password.
It should be a sufficiently longish string; say 17 random 8-bit bytes.

=head1 DESCRIPTION

This script uses the Crypt::Tea.pm module to offer TEA, the Tiny
Encryption Algorithm, and some Modes of Use based on CBC, compatibly in
both Perl and JavaScript.

The various options offer encryption, decryption and digest, and all
cyphertext is ascii-encoded to prevent munging. Another option returns
JavaScript code which offers identical functions in JS, and this can
be used by CGIs to feed to the browser.  Triple encryption will be
offered later.

Version 2.12,
#COMMENT#

=head1 AUTHOR

Peter J Billam ( http://www.pjb.com.au/comp/contact.html )

=head1 CREDITS

Based on Crypt::Tea.pm

=head1 SEE ALSO

http://www.pjb.com.au/, Crypt::Tea, http://www.cpan.org, perl(1).

=cut