1 #! /usr/bin/perl

     2 # Heiko Schlittermann

     3 use 5.014;

     4 use warnings;

     5 use Sys::Hostname;

     6 

     7 sub url_encode {

     8     shift =~ s/(?i:([^a-z]))/sprintf '%%%02x', ord $1/rge;

     9 }

    10 

    11 sub main {

    12     if (@ARGV) { splice @ARGV, 1 }

    13     else       { @ARGV = ("$ENV{HOME}/.google_authenticator") }

    14 

    15     my $google = do { local $/ = undef; <> }

    16       or die "$0: Can't read any input from $ARGV.\n";

    17 

    18     my ($secret) = $google =~ /\A(\S+)/

    19       or die "$0: Can't read secret from $ARGV.\n";

    20 

    21     my ($method) = map { lc } $google =~ /^"\s(.)\S+_AUTH$/m

    22       or die "$0: Can't read method (time/hash) from $ARGV.\n";

    23 

    24     my $user = $ENV{USER} // $ENV{LOGNAME} // getpwuid $>;

    25     my $host = hostname;

    26 

    27     open my $qr, '|qrencode -t ansi256'

    28       or die "$0: Can't open qrencode: $!\n";

    29 

    30     $qr->printf(

    31         "otpauth://%sotp/%s?secret=%s\n", $method,

    32         url_encode("$user\@$host"),       $secret

    33     );

    34 

    35     close $qr;

    36 }

    37 

    38 exit main unless caller;