File Coverage

lib/Mail/DMARC/Base.pm

Criterion	Covered	Total	%
statement	176	210	83.8
branch	67	108	62.0
condition	12	28	42.8
subroutine	38	40	95.0
pod	7	24	29.1
total	300	410	73.1

package Mail::DMARC::Base;
our $VERSION = '1.20230215';
use strict;
use warnings;
use 5.10.0;

use Carp;
use Config::Tiny;
use File::ShareDir;
use HTTP::Tiny;
use IO::File;
use Net::DNS::Resolver;
use Net::IDN::Encode qw/domain_to_unicode/;
use Net::IP;
use Regexp::Common 2013031301 qw /net/;
use Socket;
use Socket6 qw//;    # don't export symbols

sub new {
    my ( $class, @args ) = @_;
    croak "invalid args" if scalar @args % 2 != 0;
    return bless {
        config_file => 'mail-dmarc.ini',
        @args,       # this may override config_file
    }, $class;
}

my $_fake_time;
sub time { ## no critic
    # Ability to return a fake time for testing
    my ( $self ) = @_;
    my $time = defined $Mail::DMARC::Base::_fake_time ? $Mail::DMARC::Base::_fake_time : time;
    return $time;
}
sub set_fake_time {
    my ( $self, $time ) = @_;
    $Mail::DMARC::Base::_fake_time = $time;
    return;
}

sub config {
    my ( $self, $file, @too_many ) = @_;
    croak "invalid args" if scalar @too_many;
    return $self->{config} if ref $self->{config} && !$file;
    return $self->{config} = $self->get_config($file);
}

sub get_prefix {
    my ($self, $subdir) = @_;
    return map { $_ . ($subdir ? $subdir : '') } qw[ /usr/local/ /opt/local/ / ./ ];
}

sub get_sharefile {
    my ($self, $file) = @_;

    my $match = File::ShareDir::dist_file( 'Mail-DMARC', $file );
    print "using $match for $file\n" if $self->verbose;
    return $match;
}

sub get_config {
    my $self = shift;
    my $file = shift || $ENV{MAIL_DMARC_CONFIG_FILE} || $self->{config_file} or croak;
    return Config::Tiny->read($file) if -r $file;  # fully qualified
    foreach my $d ($self->get_prefix('etc')) {
        next                              if !-d $d;
        next                              if !-e "$d/$file";
        croak "unreadable file: $d/$file" if !-r "$d/$file";
        my $Config = Config::Tiny->new;
        return Config::Tiny->read("$d/$file");
    }

    if ($file ne 'mail-dmarc.ini') {
        croak "unable to find requested config file $file\n";
    }
    return Config::Tiny->read( $self->get_sharefile('mail-dmarc.ini') );
}

sub any_inet_ntop {
    my ( $self, $ip_bin ) = @_;
    $ip_bin or croak "missing IP in request";

    if ( length $ip_bin == 16 ) {
        return Socket6::inet_ntop( AF_INET6, $ip_bin );
    }

    return Socket6::inet_ntop( AF_INET, $ip_bin );
}

sub any_inet_pton {
    my ( $self, $ip_txt ) = @_;
    $ip_txt or croak "missing IP in request";

    if ( $ip_txt =~ /:/ ) {
        return Socket6::inet_pton( AF_INET6, $ip_txt )
            || croak "invalid IPv6: $ip_txt";
    }

    return Socket6::inet_pton( AF_INET, $ip_txt )
        || croak "invalid IPv4: $ip_txt";
}

{
    my $public_suffixes;
    my $public_suffixes_stamp;

    sub get_public_suffix_list {
        my ( $self ) = @_;
        if ( $public_suffixes ) { return $public_suffixes; }
        no warnings 'once';  ## no critic
        $Mail::DMARC::psl_loads++;
        my $file = $self->find_psl_file();
        $public_suffixes_stamp = ( stat( $file ) )[9];

        open my $fh, '<:encoding(UTF-8)', $file
            or croak "unable to open $file for read: $!\n";
        # load PSL into hash for fast lookups, esp. for long running daemons
        my %psl = map { $_ => 1 }
                  grep { $_ !~ /^[\/\s]/ } # weed out comments & whitespace
                  map { chomp($_); $_ }    ## no critic, remove line endings
                  <$fh>;
        close $fh;
        return $public_suffixes = \%psl;
    }

    sub check_public_suffix_list {
        my ( $self ) = @_;
        my $file = $self->find_psl_file();
        my $new_public_suffixes_stamp = ( stat( $file ) )[9];
        if ( $new_public_suffixes_stamp != $public_suffixes_stamp ) {
            $public_suffixes = undef;
            $self->get_public_suffix_list();
            return 1;
        }
        return 0;
     }
 }

sub is_public_suffix {
    my ( $self, $zone ) = @_;

    croak "missing zone name!" if !$zone;

    my $public_suffixes = $self->get_public_suffix_list();

    $zone = domain_to_unicode( $zone ) if $zone =~ /xn--/;

    return 1 if $public_suffixes->{$zone};

    my @labels = split /\./, $zone;
    $zone = join '.', '*', (@labels)[ 1 .. scalar(@labels) - 1 ];

    return 1 if $public_suffixes->{$zone};
    return 0;
}

sub update_psl_file {
    my ($self, $dryrun) = @_;

    my $psl_file = $self->find_psl_file();

    die "No Public Suffix List file found\n"                  if ( ! $psl_file );
    die "Public suffix list file $psl_file not found\n"       if ( ! -f $psl_file );
    die "Cannot write to Public Suffix List file $psl_file\n" if ( ! -w $psl_file );

    my $url = 'https://publicsuffix.org/list/effective_tld_names.dat';
    if ( $dryrun ) {
        print "Will attempt to update the Public Suffix List file at $psl_file (dryrun mode)\n";
        return;
    }

    my $response = HTTP::Tiny->new->mirror( $url, $psl_file );
    my $content = $response->{'content'};
    if ( !$response->{'success'} ) {
        my $status = $response->{'status'};
        die "HTTP Request for Public Suffix List file failed with error $status ($content)\n";
    }
    else {
        if ( $response->{'status'} eq '304' ) {
            print "Public Suffix List file $psl_file not modified\n";
        }
        else {
            print "Public Suffix List file $psl_file updated\n";
        }
    }
    return;
}

sub find_psl_file {
    my ($self) = @_;

    my $file = $self->config->{dns}{public_suffix_list} || 'share/public_suffix_list';
    if ( $file =~ /^\// && -f $file && -r $file ) {
        print "using $file for Public Suffix List\n" if $self->verbose;
        return $file;
    }
    my $path;
    foreach $path ($self->get_prefix('share/' . $file)) {    ## no critic
        last if ( -f $path && -r $path );
    }
    if ($path && -r $path) {
        print "using $path for Public Suffix List\n" if $self->verbose;
        return $path;
    };

    # Fallback to included suffic list
    return $self->get_sharefile('public_suffix_list');
}

sub has_dns_rr {
    my ( $self, $type, $domain ) = @_;

    my @matches;
    my $res     = $self->get_resolver();
    my $query   = $res->query( $domain, $type ) or do {
        return 0 if ! wantarray;
        return @matches;
    };
    for my $rr ( $query->answer ) {
        next if $rr->type ne $type;
        push @matches, $rr->type eq  'A'   ? $rr->address
                     : $rr->type eq 'PTR'  ? $rr->ptrdname
                     : $rr->type eq  'NS'  ? $rr->nsdname
                     : $rr->type eq  'TXT' ? $rr->txtdata
                     : $rr->type eq  'SPF' ? $rr->txtdata
                     : $rr->type eq 'AAAA' ? $rr->address
                     : $rr->type eq  'MX'  ? $rr->exchange
                     : $rr->answer;
    }
    return scalar @matches if ! wantarray;
    return @matches;
}

sub epoch_to_iso {
    my ($self, $epoch) = @_;

    my @fields = localtime( $epoch );

    my $ss = sprintf( "%02i", $fields[0] );    # seconds
    my $mn = sprintf( "%02i", $fields[1] );    # minutes
    my $hh = sprintf( "%02i", $fields[2] );    # hours (24 hour clock)

    my $dd = sprintf( "%02i", $fields[3] );        # day of month
    my $mm = sprintf( "%02i", $fields[4] + 1 );    # month
    my $yy = ( $fields[5] + 1900 );                # year

    return "$yy-$mm-$dd" .'T'."$hh:$mn:$ss";
}

sub get_resolver {
    my $self = shift;
    my $timeout = shift || $self->config->{dns}{timeout} || 5;
    return $self->{resolver} if defined $self->{resolver};
    $self->{resolver} = Net::DNS::Resolver->new( dnsrch => 0 );
    $self->{resolver}->tcp_timeout($timeout);
    $self->{resolver}->udp_timeout($timeout);
    return $self->{resolver};
}

sub set_resolver {
    my ($self,$resolver) = @_;
    $self->{resolver} = $resolver;
    return;
}

sub is_valid_ip {
    my ( $self, $ip ) = @_;

    # Using Regexp::Common removes perl 5.8 compat
    # Perl 5.008009 does not support the pattern $RE{net}{IPv6}.
    # You need Perl 5.01 or later

    if ( $ip =~ /:/ ) {
        return Net::IP->new( $ip, 6 );
    }

    return Net::IP->new( $ip, 4 );
}

sub is_valid_domain {
    my ( $self, $domain ) = @_;
    return 0 if $domain !~ /^$RE{net}{domain}{-rfc1101}{-nospace}$/x;
    my $tld = ( split /\./, lc $domain )[-1];
    return 1 if $self->is_public_suffix($tld);
    $tld = join( '.', ( split /\./, $domain )[ -2, -1 ] );
    return 1 if $self->is_public_suffix($tld);
    return 0;
}

sub is_valid_spf_scope {
    my ($self, $scope ) = @_;
    return lc $scope if grep { lc $scope eq $_ } qw/ mfrom helo /;
    carp "$scope is not a valid SPF scope";
    return;
}

sub is_valid_spf_result {
    my ($self, $result ) = @_;
    return 1 if grep { lc $result eq $_ }
        qw/ fail neutral none pass permerror softfail temperror /;
    carp "$result is not a valid SPF result";
    return;
}

sub slurp {
    my ( $self, $file ) = @_;
    open my $FH, '<', $file or croak "unable to read $file: $!";
    my $contents = do { local $/; <$FH> };    ## no critic (Local)
    close $FH;
    return $contents;
}

sub verbose {
    return $_[0]->{verbose} if 1 == scalar @_;
    return $_[0]->{verbose} = $_[1];
}

1;

__END__