#!/usr/bin/perl -w
#
#  cram-md5.pl
#  -----------
#  
#  Generate responses to CRAM-MD5 challenges for IMAP4 and SMTP authentication.
#
#  See RFCs 2195 (CRAM-MD5), 1731 (IMAP AUTH) and 2554 (SMTP AUTH)
#
#  $Id: cram-md5.pl,v 1.2 2004/01/28 12:03:46 tjd Exp $
#

use strict;
use Digest::HMAC_MD5 qw(hmac_md5_hex);
use MIME::Base64;

if ($#ARGV != 2) {
    print "Usage: $0 <challenge> <username> <password>\n";
    exit(1);
}

my ($challenge, $username, $password) = @ARGV;
my $response = hmac_md5_hex(decode_base64($challenge), $password);
print encode_base64("$username $response");

#
#  EOF (cram-md5.pl)
#