qrserve

#!/usr/bin/perl
use strict;
use warnings;
use 5.10.0;

# serves up a QR code as a PNG in response to
# http://127.0.0.1:3536/qr/BASE32SECRET.  Note that the IP should not be
# changed, for security reasons, although the port is fine.

{

    package MyWebServer;

    use HTTP::Server::Simple::CGI;
    use base qw(HTTP::Server::Simple::CGI);

    sub handle_request {
        my $self = shift;
        my $cgi  = shift;
        $|++;

        if ( $cgi->path_info() =~ m(^/qr/([A-Z2-7]+)$)i ) {
            print "HTTP/1.0 200 OK\r\n";
            qrcode($1);
        } else {
            print "HTTP/1.0 404 Not found\r\n";
            print $cgi->header, $cgi->start_html('Bad Base32 string'), $cgi->h1('Bad Base32 string'), $cgi->end_html;
        }
    }

    sub qrcode {
        my $secret = shift;
        my $hn = `hostname -s`; chomp($hn);

        print "Content-Type: image/png\r\n";
        print "\r\n";

        # print $cgi->header('image/png');

        print `qrencode -s16 -m1 -o- otpauth://totp/$hn?secret=$secret`;
    }

}

my $x = MyWebServer->new;
$x->host('127.0.0.1');
$x->port(3536);
$x->background();