aws-header-filter.pl

aws-header-filter.pl

#!/usr/bin/perl

use strict;
use warnings;

my @legal_headers = qw( Accept-Language Bcc Cc Comments Content-Type Content-Transfer-Encoding Content-ID Content-Description Content-Disposition Content-Language Date DKIM-Signature DomainKey-Signature From In-Reply-To Keywords List-Archive List-Help List-Id List-Owner List-Post List-Subscribe List-Unsubscribe Message-Id MIME-Version Received References Reply-To Return-Path Sender Subject Thread-Index Thread-Topic To User-Agent );

my %legal_headers;
@legal_headers{@legal_headers} = (1) x @legal_headers;

my $in_header = 1;
my $in_body = 0;

while(<>) {
        # Two linebreaks between header & body
        if ($in_header && ($_ =~ /^[\n\r]/)) {
                $in_header = 0;
                $in_body = 1;
        }
        if ($in_header) { # Once we leave the header, do nothing.
                if ($_ =~ /^([\w\d\-]+):/) { # skips indented lines
                        my $header = $1;
                        if ($legal_headers{$header}) {
                        #       print "Legal header: $header\n";
                                print;
                        } else {
                                if ($header =~ /^X-/) { # If it's already an X-header, don't touch
                                        print;
                                } else {
                                        $_ =~ s/^$header:/X-$header:/; # X-ify
                                        print;
                                }
                        }
                } else {
                        print;
                } 
        } 
#       print;

}