#!perl -Tw

=head1 NAME

syslog - Syslog logging plugin for qpsmtpd

=head1 DESCRIPTION

The syslog plugin for qpsmtpd passes qpsmtpd log messages into the standard
UNIX syslog facility, mapping qpsmtpd priorities to syslog priorities.

=head1 CONFIGURATION

To enable the logging plugin, add a line of this form to the qpsmtpd plugins
configuration file:

=over

logging/syslog [loglevel l] [priority p] [ident str] [facility f] [logsock t]

For example:

logging/syslog loglevel LOGINFO priority LOG_NOTICE

=back

The following optional configuration settings can be supplied:

=over

=item B<loglevel>

The internal log level below which messages will be logged.  Priorities count
downward as follows:

=over

=item B<LOGDEBUG>

=item B<LOGINFO>

=item B<LOGNOTICE>

=item B<LOGWARN>

=item B<LOGERROR>

=item B<LOGCRIT>

=item B<LOGALERT>

=item B<LOGEMERG>

=back


=item B<priority>

Normally, log messages will be mapped from the above log levels into the
syslog(3) log levels of their corresponding names.  This will cause various
messages to appear or not in syslog outputs according to your syslogd
configuration (typically /etc/syslog.conf).  However, if the B<priority>
setting is used, all messages will be logged at that priority regardless of
what the original priority might have been.

=item B<ident>

The ident string that will be attached to messages logged via this plugin.
The default is 'qpsmtpd'.

=item B<facility>

The syslog facility to which logged mesages will be directed.  See syslog(3)
for details.  The default is LOG_MAIL.

=item B<logsock>

The syslog socket where messages should be sent via syslogsock().  The valid
options are 'udp', 'tcp', 'unix', 'stream' and 'console'.  Not all are
available on all systems.  See Sys::Syslog for details.  The default is
the above list in that order.  To select specific sockets, use a comma to
separate the types.

=over

    logsock udp,unix
    logsock stream

=back

=back

=head1 AUTHOR

Devin Carraway <qpsmtpd@devin.com>
Peter Eisch <peter@boku.net> (logsock support)

=head1 LICENSE

Copyright (c) 2005, Devin Carraway.

This plugin is licensed under the same terms as the qpsmtpd package itself.
Please see the LICENSE file included with qpsmtpd for details.

=cut

use strict;
use warnings;

use Qpsmtpd::Constants;
use Sys::Syslog qw(:DEFAULT setlogsock);

sub register {
    my ($self, $qp, @args) = @_;
    my %args;

    if (@args % 2 == 0) {
        %args = @args;
    } else {
        warn "Malformed arguments to syslog plugin";
        return;
    }

    my $ident = 'qpsmtpd';
    my $logopt = 'pid';
    my $facility = 'LOG_MAIL';

    $self->{_loglevel} = LOGWARN;

    if ($args{loglevel}) {
        if ($args{loglevel} =~ /^(\d+)$/) {
            $self->{_loglevel} = $1;
        }
        elsif ($args{loglevel} =~ /^(LOG\w+)$/) {
            $self->{_loglevel} = log_level($1) || LOGWARN;
        }
    }

    if ($args{priority}) {
        if ($args{priority} =~ /^(\d+|LOG\w+)$/) {
            $self->{_priority} = $1;
        }
    }

    if ($args{ident} && $args{ident} =~ /^([\w\-.]+)$/) {
        $ident = $1;
    }
    if ($args{facility} && $args{facility} =~ /^(\w+)$/) {
        $facility = $1;
    }

    if ($args{logsock}) {
       my @logopt = split(/,/, $args{logsock});
       setlogsock(@logopt);
    }

    unless (openlog $ident, $logopt, $facility) {
        warn "Error opening syslog output";
        return;
    }
}

my %priorities_ = (
    0 => 'LOG_EMERG',
    1 => 'LOG_ALERT',
    2 => 'LOG_CRIT',
    3 => 'LOG_ERR',
    4 => 'LOG_WARNING',
    5 => 'LOG_NOTICE',
    6 => 'LOG_INFO',
    7 => 'LOG_DEBUG',
);

sub hook_logging {
    my ($self, $transaction, $trace, $hook, $plugin, @log) = @_;

    return DECLINED if $trace > $self->{_loglevel};
    return DECLINED if defined $plugin and $plugin eq $self->plugin_name;

    my $priority = $self->{_priority} ?
                   $self->{_priority} : $priorities_{$trace};

    syslog $priority, '%s', join(' ', @log);
    return DECLINED;
}