#! /usr/bin/perl -w
#
# reads an article on STDIN, mails any copies if requied,
# signs the article and posts it.
#
#
# Copyright (c) 2002-2014 Urs Janssen <urs@tin.org>,
#                         Marc Brockschmidt <marc@marcbrockschmidt.de>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote
#    products derived from this software without specific prior written
#    permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
#
# TODO: - add debug mode which doesn't delete tmp-files and is verbose
#       - add pid to pgptmpf to allow multiple simultaneous instances
#       - check for /etc/nntpserver (and /etc/news/server)
#       - add $PGPOPTS, $PGPPATH and $GNUPGHOME support
#       - cleanup and remove duplicated code
#       - option to convert CRLF to LF in input
#

use strict;
use warnings;

# version Number
my $version = "1.1.39";

my %config;

# configuration, may be overwritten via ~/.tinewsrc
$config{'NNTPServer'}	= 'news';	# your NNTP servers name, may be set via $NNTPSERVER
$config{'NNTPPort'}		= 119;	# NNTP-port, may be set via $NNTPPORT
$config{'NNTPUser'}		= '';	# username for nntp-auth, may be set via ~/.newsauth or ~/.nntpauth
$config{'NNTPPass'}		= '';	# password for nntp-auth, may be set via ~/.newsauth or ~/.nntpauth

$config{'PGPSigner'}	= '';	# sign as who?
$config{'PGPPass'}		= '';	# pgp2 only
$config{'PathtoPGPPass'}= '';	# pgp2, pgp5, pgp6 and gpg
$config{'PGPPassFD'}	= 9;	# file descriptor used for input redirection of PathtoPGPPass, GPG, PGP5 and PGP6 only

$config{'pgp'}			= '/usr/bin/pgp';	# path to pgp
$config{'PGPVersion'}	= '2';	# Use 2 for 2.X, 5 for PGP5, 6 for PGP6 and GPG for GPG
$config{'digest-algo'}	= 'MD5';# Digest Algorithm for GPG. Must be supported by your installation

$config{'Interactive'}	= 'yes';# allow interactive usage

$config{'sig_path'}		= glob('~/.signature');	# path to signature
$config{'add_signature'}= 'yes';# Add $config{'sig_path'} to posting if there is no sig
$config{'sig_max_lines'}= 4;	# max number of signatures lines

$config{'sendmail'}		= '| /usr/sbin/sendmail -i -t'; # set to '' to disable mail-actions

$config{'pgptmpf'}		= 'pgptmp';	# temporary file for PGP.

$config{'pgpheader'}	= 'X-PGP-Sig';
$config{'pgpbegin'}		= '-----BEGIN PGP SIGNATURE-----';	# Begin of PGP-Signature
$config{'pgpend'}		= '-----END PGP SIGNATURE-----';	# End of PGP-Signature

# $config{'canlock_secret'}	= '~/.cancelsecret';		# Path to canlock secret file

$config{'PGPSignHeaders'} = ['From', 'Newsgroups', 'Subject', 'Control',
	'Supersedes', 'Followup-To', 'Date', 'Injection-Date', 'Sender', 'Approved',
	'Message-ID', 'Reply-To', 'Cancel-Key', 'Also-Control',
	'Distribution'];
$config{'PGPorderheaders'} = ['from', 'newsgroups', 'subject', 'control',
	'supersedes', 'followup-To', 'date', 'injection-date', 'organization',
	'lines', 'sender', 'approved', 'distribution', 'message-id',
	'references', 'reply-to', 'mime-version', 'content-type',
	'content-transfer-encoding', 'summary', 'keywords', 'cancel-lock',
	'cancel-key', 'also-control', 'x-pgp', 'user-agent'];

################################################################################

use Getopt::Long qw(GetOptions);
use Net::NNTP;
use Time::Local;
use Term::ReadLine;

(my $pname = $0) =~ s#^.*/##;

# read config file (first match counts) from
# $XDG_CONFIG_HOME/tinewsrc ~/.config/tinewsrc ~/.tinewsrc
# if present
my $TINEWSRC = undef;
my (@try, %seen);
if ($ENV{'XDG_CONFIG_HOME'}) {
	push(@try, (glob("$ENV{'XDG_CONFIG_HOME'}/tinewsrc"))[0]);
}
push(@try, (glob('~/.config/tinewsrc'))[0], (glob('~/.tinewsrc'))[0]);

foreach (grep { ! $seen{$_}++ } @try) {
	last if (open($TINEWSRC, '<', $_));
	$TINEWSRC = undef;
}
if (defined($TINEWSRC)) {
	while (defined($_ = <$TINEWSRC>)) {
		if (m/^([^#\s=]+)\s*=\s*(\S[^#]+)/io) {
			chomp($config{$1} = $2);
		}
	}
	close($TINEWSRC);
}

# digest-algo is case sensitive and should be all uppercase
$config{'digest-algo'} = uc($config{'digest-algo'});

# these env-vars have higher priority
$config{'NNTPServer'} = $ENV{'NNTPSERVER'} if ($ENV{'NNTPSERVER'});
$config{'NNTPPort'} = $ENV{'NNTPPORT'} if ($ENV{'NNTPPORT'});

# Get options:
$Getopt::Long::ignorecase=0;
$Getopt::Long::bundling=1;
GetOptions('A|V|W|O|no-organization|h|headers' => [], # do nothing
	'debug|D|N'	=> \$config{'debug'},
	'port|p=i'	=> \$config{'NNTPPort'},
	'no-sign|X'	=> \$config{'no_sign'},
	'no-control|R'	=> \$config{'no_control'},
	'no-signature|S'	=> \$config{'no_signature'},
	'no-canlock|L'	=> \$config{'no_canlock'},
	'force-auth|Y'	=> \$config{'force_auth'},
	'approved|a=s'	=> \$config{'approved'},
	'control|c=s'	=> \$config{'control'},
	'distribution|d=s'	=> \$config{'distribution'},
	'expires|e=s'	=> \$config{'expires'},
	'from|f=s'	=> \$config{'from'},
	'followupto|w=s'	=> \$config{'followup-to'},
	'newsgroups|n=s'	=> \$config{'newsgroups'},
	'replyto|r=s'	=> \$config{'reply-to'},
	'savedir|s=s'	=> \$config{'savedir'},
	'subject|t=s'	=> \$config{'subject'},
	'references|F=s'	=> \$config{'references'},
	'organization|o=s'	=> \$config{'organization'},
	'path|x=s'	=> \$config{'path'},
	'help|H'	=> \$config{'help'},
	'version|v'	=> \$config{'version'}
);

foreach (@ARGV) {
	print STDERR "Unknown argument $_.";
	usage();
}

if ($config{'version'}) {
	version();
	exit 0;
}

usage() if ($config{'help'});

my $sha_mod=undef;
# Cancel-Locks require some more modules
if ($config{'canlock_secret'} && !$config{'no_canlock'}) {
	foreach ('Digest::SHA qw(sha1)', 'Digest::SHA1()') {
		eval "use $_";
		if (!$@) {
			($sha_mod = $_) =~ s#( qw\(sha1\)|\(\))##;
			last;
		}
	}
	foreach ('MIME::Base64()', 'Digest::HMAC_SHA1()') {
		eval "use $_";
		if ($@ || !defined($sha_mod)) {
			$config{'no_canlock'} = 1;
			warn "Cancel-Locks disabled: Can't locate ".$_."\n" if $config{'debug'};
			last;
		}
	}
}

my $term = Term::ReadLine->new('tinews');
my $attribs = $term->Attribs;
my $in_header = 1;
my (%Header, @Body, $PGPCommand);

if (! $config{'no_sign'}) {
	$config{'PGPSigner'} = $ENV{'SIGNER'} if ($ENV{'SIGNER'});
	$config{'PathtoPGPPass'} = $ENV{'PGPPASSFILE'} if ($ENV{'PGPPASSFILE'});
	if ($config{'PathtoPGPPass'}) {
		open(my $PGPPass, '<', (glob($config{'PathtoPGPPass'}))[0]) or
			$config{'Interactive'} && die("$0: Can't open ".$config{'PathtoPGPPass'}.": $!");
		chomp($config{'PGPPass'} = <$PGPPass>);
		close($PGPPass);
	}
	if ($config{'PGPVersion'} eq '2' && $ENV{'PGPPASS'}) {
		$config{'PGPPass'} = $ENV{'PGPPASS'};
	}
}


# Read the message and split the header
readarticle(\%Header, \@Body);

# Add signature if there is none
if (!$config{'no_signature'}) {
	if ($config{'add_signature'} && !grep {/^-- /} @Body) {
		if (-r $config{'sig_path'}) {
			my $l = 0;
			push @Body, "-- \n";
			open(my $SIGNATURE, '<', $config{'sig_path'}) or die("Can't open " . $config{'sig_path'} . ": $!");
			while (<$SIGNATURE>){
				die $config{'sig_path'} . " longer than " . $config{'sig_max_lines'}. " lines!" if (++$l > $config{'sig_max_lines'});
				push @Body, $_;
			}
			close($SIGNATURE);
		} else {
			if ($config{'debug'}) {
				warn "Tried to add " . $config{'sig_path'} . ", but it is unreadable";
			}
		}
	}
}

# import headers set in the environment
if (!defined($Header{'reply-to'})) {
	if ($ENV{'REPLYTO'}) {
		chomp($Header{'reply-to'} = "Reply-To: " . $ENV{'REPLYTO'});
		$Header{'reply-to'} .= "\n";
	}
}
foreach ('DISTRIBUTION', 'ORGANIZATION') {
	if (!defined($Header{lc($_)}) && $ENV{$_}) {
		chomp($Header{lc($_)} = ucfirst($_).": " . $ENV{$_});
		$Header{lc($_)} .= "\n";
	}
}

# overwrite headers if specified via cmd-line
foreach ('Approved', 'Control', 'Distribution', 'Expires',
	'From', 'Followup-To', 'Newsgroups',' Reply-To', 'Subject',
	'References', 'Organization', 'Path') {
	next if (!defined($config{lc($_)}));
	chomp($Header{lc($_)} = $_ . ": " . $config{lc($_)});
	$Header{lc($_)} .= "\n";
}

# verify/add/remove headers
foreach ('From', 'Subject') {
	die("$0: No $_:-header defined.") if (!defined($Header{lc($_)}));
}

$Header{'date'} = "Date: ".getdate()."\n" if (!defined($Header{'date'}) || $Header{'date'} !~ m/^[^\s:]+: .+/o);
$Header{'injection-date'} = "Injection-Date: ".getdate()."\n";

if (defined($Header{'user-agent'})) {
	chomp $Header{'user-agent'};
	$Header{'user-agent'} = $Header{'user-agent'}." ".$pname."/".$version."\n";
}

delete $Header{'x-pgp-key'} if (!$config{'no_sign'} && defined($Header{'x-pgp-key'}));


# No control messages allowed when using -R|--no-control
if ($config{'no_control'} and $Header{control}) {
	print STDERR "No control messages allowed.\n";
	exit 1;
}

# various checks
if ($config{'debug'}) {
	foreach (keys %Header) {
		warn "Raw 8-bit data in the following header:\n$Header{$_}" if ($Header{$_} =~ m/[\x80-\xff]/o);
	}
	if (!defined($Header{'mime-version'}) || !defined($Header{'content-type'}) || !defined($Header{'content-transfer-encoding'})) {
		warn "8bit body without MIME-headers\n" if (grep {/[\x80-\xff]/} @Body);
	}
}

# try ~/.newsauth if no $config{'NNTPPass'} was set
if (!$config{'NNTPPass'}) {
	my ($l, $server, $pass, $user);
	if (-r (glob("~/.newsauth"))[0]) {
		open (my $NEWSAUTH, '<', (glob("~/.newsauth"))[0]) or die("Can't open ~/.newsauth: $!");
		while ($l = <$NEWSAUTH>) {
			chomp $l;
			next if ($l =~ m/^[#\s]/);
			($server, $pass, $user) = split(/\s+\b/, $l);
			last if ($server =~ m/\Q$config{'NNTPServer'}\E/);
		}
		close($NEWSAUTH);
		if ($pass && $server =~ m/\Q$config{'NNTPServer'}\E/) {
			$config{'NNTPPass'} = $pass;
			$config{'NNTPUser'} = $user || getlogin || getpwuid($<) || $ENV{USER};
		} else {
			$pass = $user = "";
		}
	}
	# try ~/.nntpauth if we still got no password
	if (!$pass) {
		if (-r (glob("~/.nntpauth"))[0]) {
			open (my $NNTPAUTH, '<', (glob("~/.nntpauth"))[0]) or die("Can't open ~/.nntpauth: $!");
			while ($l = <$NNTPAUTH>) {
				chomp $l;
				next if ($l =~ m/^[#\s]/);
				($server, $user, $pass) = split(/\s+\b/, $l);
				last if ($server =~ m/\Q$config{'NNTPServer'}\E/);
			}
			close($NNTPAUTH);
			if ($pass && $server =~ m/\Q$config{'NNTPServer'}\E/) {
				$config{'NNTPPass'} = $pass;
				$config{'NNTPUser'} = $user || getlogin || getpwuid($<) || $ENV{USER};
			}
		}
	}
}

if (! $config{'savedir'} && defined($Header{'newsgroups'}) && !defined($Header{'message-id'})) {
	my $Server = AuthonNNTP();
	my $ServerMsg = $Server->message();
	$Server->datasend('.');
	$Server->dataend();
	$Server->quit();
	$Header{'message-id'} = "Message-ID: $1\n" if ($ServerMsg =~ m/(<\S+\@\S+>)/o);
}

if (!defined($Header{'message-id'})) {
	my $hname;
	eval "use Sys::Hostname";
	if ($@) {
		chomp($hname = `hostname`);
	} else {
		$hname = hostname();
	}
	my ($hostname,) = gethostbyname($hname);
	if (defined($hostname) && $hostname =~ m/\./io) {
		$Header{'message-id'} = "Message-ID: " . sprintf("<N%xI%xT%x@%s>\n", $>, timelocal(localtime), $$, $hostname);
	}
}

# add Cancel-Lock (and Cancel-Key) header(s) if requested
if ($config{'canlock_secret'} && !$config{'no_canlock'} && defined($Header{'message-id'})) {
	open(my $CANLock, '<', (glob($config{'canlock_secret'}))[0]) or die("$0: Can't open " . $config{'canlock_secret'} . ": $!");
	chomp(my $key = <$CANLock>);
	close($CANLock);
	(my $data = $Header{'message-id'}) =~ s#^Message-ID: ##i;
	chomp $data;
	my $digest = Digest::HMAC_SHA1::hmac_sha1($data, $key);
	my $cancel_key = MIME::Base64::encode($digest, '');
	my $cancel_lock;
	if ($sha_mod =~ m/SHA1/) {
		$cancel_lock = MIME::Base64::encode(Digest::SHA1::sha1($cancel_key, ''));
	} else {
		$cancel_lock = MIME::Base64::encode(Digest::SHA::sha1($cancel_key, ''));
	}
	if (defined($Header{'cancel-lock'})) {
		chomp $Header{'cancel-lock'};
		$Header{'cancel-lock'} .= " sha1:" . $cancel_lock;
	} else {
		$Header{'cancel-lock'} = "Cancel-Lock: sha1:" . $cancel_lock;
	}

	if ((defined($Header{'supersedes'}) && $Header{'supersedes'} =~ m/^Supersedes:\s+<\S+>\s*$/i) || (defined($Header{'control'}) && $Header{'control'} =~ m/^Control:\s+cancel\s+<\S+>\s*$/i) ||(defined($Header{'also-control'}) && $Header{'also-control'} =~ m/^Also-Control:\s+cancel\s+<\S+>\s*$/i)) {
		if (defined($Header{'also-control'}) && $Header{'also-control'} =~ m/^Also-Control:\s+cancel\s+/i) {
			($data = $Header{'also-control'}) =~ s#^Also-Control:\s+cancel\s+##i;
			chomp $data;
			$cancel_key = MIME::Base64::encode(Digest::HMAC_SHA1::hmac_sha1($data, $key),'');
		} else {
			if (defined($Header{'control'}) && $Header{'control'} =~ m/^Control: cancel /i) {
				($data = $Header{'control'})=~ s#^Control:\s+cancel\s+##i;
				chomp $data;
				$cancel_key = MIME::Base64::encode(Digest::HMAC_SHA1::hmac_sha1($data, $key),'');
			} else {
				if (defined($Header{'supersedes'})) {
					($data = $Header{'supersedes'}) =~ s#^Supersedes: ##i;
					chomp $data;
					$cancel_key = MIME::Base64::encode(Digest::HMAC_SHA1::hmac_sha1($data, $key),'');
				}
			}
		}
		if (defined($Header{'cancel-key'})) {
			chomp $Header{'cancel-key'};
			$Header{'cancel-key'} .= " sha1:" . $cancel_key . "\n";
		} else {
			$Header{'cancel-key'} = "Cancel-Key: sha1:" . $cancel_key . "\n";
		}
	}
}

# set Posted-And-Mailed if we send a mailcopy to someone else
if ($config{'sendmail'} && defined($Header{'newsgroups'}) && (defined($Header{'to'}) || defined($Header{'cc'}) || defined($Header{'bcc'}))) {
	foreach ('to', 'bcc', 'cc') {
		if (defined($Header{$_}) && $Header{$_} ne $Header{'from'}) {
			$Header{'posted-and-mailed'} = "Posted-And-Mailed: yes\n";
			last;
		}
	}
}

if (! $config{'no_sign'}) {
	if (!$config{'PGPSigner'}) {
		chomp($config{'PGPSigner'} = $Header{'from'});
		$config{'PGPSigner'} =~ s/^[^\s:]+: (.*)/$1/;
	}
	$PGPCommand = getpgpcommand($config{'PGPVersion'});
}

# (re)move mail-headers
my ($To, $Cc, $Bcc, $Newsgroups) = '';
$To = $Header{'to'} if (defined($Header{'to'}));
$Cc = $Header{'cc'} if (defined($Header{'cc'}));
$Bcc = $Header{'bcc'} if (defined($Header{'bcc'}));
delete $Header{$_} foreach ('to', 'cc', 'bcc');
$Newsgroups = $Header{'newsgroups'} if (defined($Header{'newsgroups'}));

my $MessageR = [];

if ($config{'no_sign'}) {
	# don't sign article
	push @$MessageR, $Header{$_} for (keys %Header);
	push @$MessageR, "\n", @Body;
} else {
	# sign article
	$MessageR = signarticle(\%Header, \@Body);
}

# post or save article
if (! $config{'savedir'}) {
	postarticle($MessageR) if ($Newsgroups);
} else {
	savearticle($MessageR) if ($Newsgroups);
}

# mail article
if (($To || $Cc || $Bcc) && $config{'sendmail'}) {
	open(my $MAIL, $config{'sendmail'}) || die("$!");
	unshift @$MessageR, "$To" if ($To);
	unshift @$MessageR, "$Cc" if ($Cc);
	unshift @$MessageR, "$Bcc" if ($Bcc);
	print($MAIL @$MessageR);
	close($MAIL);
}

# Game over. Insert new coin.
exit;


#-------- sub readarticle
#
sub readarticle {
	my ($HeaderR, $BodyR) = @_;
	my $currentheader;
	while (defined($_ = <>)) {
		if ($in_header) {
			if (m/^$/o) { #end of header
				$in_header = 0;
			} elsif (m/^([^\s:]+): (.*)$/s) {
				$currentheader = lc($1);
				$$HeaderR{$currentheader} = "$1: $2";
			} elsif (m/^[ \t]/o) {
				$$HeaderR{$currentheader} .= $_;
#			} elsif (m/^([^\s:]+):$/) { # skip over empty headers
#				next;
			} else {
				chomp($_);
				# TODO: quote esc. sequences?
				die("'$_' is not a correct header-line");
			}
		} else {
			push @$BodyR, $_;
		}
	}
	return;
}

#-------- sub getdate
# getdate generates a date and returns it.
#
sub getdate {
	my @time = localtime;
	my $ss = ($time[0]<10) ? "0".$time[0] : $time[0];
	my $mm = ($time[1]<10) ? "0".$time[1] : $time[1];
	my $hh = ($time[2]<10) ? "0".$time[2] : $time[2];
	my $day = $time[3];
	my $month = ($time[4]+1 < 10) ? "0".($time[4]+1) : $time[4]+1;
	my $monthN = ("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec")[$time[4]];
	my $wday = ("Sun","Mon","Tue","Wed","Thu","Fri","Sat")[$time[6]];
	my $year = $time[5] + 1900;
	my $offset = timelocal(localtime) - timelocal(gmtime);
	my $sign ="+";
	if ($offset < 0) {
		$sign ="-";
		$offset *= -1;
	}
	my $offseth = int($offset/3600);
	my $offsetm = int(($offset - $offseth*3600)/60);
	my $tz = sprintf ("%s%0.2d%0.2d", $sign, $offseth, $offsetm);
	return "$wday, $day $monthN $year $hh:$mm:$ss $tz";
}


#-------- sub AuthonNNTP
# AuthonNNTP opens the connection to a Server and returns a Net::NNTP-Object.
#
# User, Password and Server are defined before as elements
# of the global hash %config. If no values for user or password
# are defined, the sub will try to ask the user (only if
# $config{'Interactive'} is != 0).
sub AuthonNNTP {
	my $Server = Net::NNTP->new($config{'NNTPServer'}, Reader => 1, Debug => 0, Port => $config{'NNTPPort'})
		or die("$0: Can't connect to ".$config{'NNTPServer'}.":".$config{'NNTPPort'}."!\n");
	my $ServerMsg = "";
	my $ServerCod = $Server->code();

	# no read and/or write access - give up
	if ($ServerCod < 200 || $ServerCod > 201) {
		$ServerMsg = $Server->message();
		$Server->quit();
		die($0.": ".$ServerCod." ".$ServerMsg."\n");
	}

	# read access - try auth
	if ($ServerCod == 201 || $config{'force_auth'}) {
		if ($config{'NNTPPass'} eq "") {
			if ($config{'Interactive'}) {
				$config{'NNTPUser'} = $term->readline("Your Username at ".$config{'NNTPServer'}.": ");
				$attribs->{redisplay_function} = $attribs->{shadow_redisplay};
				$config{'NNTPPass'} = $term->readline("Password for ".$config{'NNTPUser'}." at ".$config{'NNTPServer'}.": ");
			} else {
				$ServerMsg = $Server->message();
				$Server->quit();
				die($0.": ".$ServerCod." ".$ServerMsg."\n");
			}
		}
		$Server->authinfo($config{'NNTPUser'}, $config{'NNTPPass'});
		$ServerCod = $Server->code();
		$ServerMsg = $Server->message();
		if ($ServerCod != 281) { # auth failed
			$Server->quit();
			die $0.": ".$ServerCod." ".$ServerMsg."\n";
		}
	}

	$Server->post();
	$ServerCod = $Server->code();
	if ($ServerCod == 480) {
		if ($config{'NNTPPass'} eq "") {
			if ($config{'Interactive'}) {
				$config{'NNTPUser'} = $term->readline("Your Username at ".$config{'NNTPServer'}.": ");
				$attribs->{redisplay_function} = $attribs->{shadow_redisplay};
				$config{'NNTPPass'} = $term->readline("Password for ".$config{'NNTPUser'}." at ".$config{'NNTPServer'}.": ");
			} else {
				$ServerMsg = $Server->message();
				$Server->quit();
				die($0.": ".$ServerCod." ".$ServerMsg."\n");
			}
		}
		$Server->authinfo($config{'NNTPUser'}, $config{'NNTPPass'});
		$Server->post();
	}
	return $Server;
}


#-------- sub getpgpcommand
# getpgpcommand generates the command to sign the message and returns it.
#
# Receives:
# 	- $PGPVersion: A scalar holding the PGPVersion
sub getpgpcommand {
	my ($PGPVersion) = @_;
	my $found = 0;

	if ($config{'pgp'} !~ /^\//) {
		foreach(split(/:/, $ENV{'PATH'})) {
			if (-x $_."/".$config{'pgp'}) {
				$found++;
				last;
			}
		}
	}
	if (!-x $config{'pgp'} && ! $found) {
		warn "PGP signing disabled: Can't locate executable ".$config{'pgp'}."\n" if $config{'debug'};
		$config{'no_sign'} = 1;
	}

	if ($PGPVersion eq '2') {
		if ($config{'PGPPass'}) {
			$PGPCommand = "PGPPASS=\"".$config{'PGPPass'}."\" ".$config{'pgp'}." -z -u \"".$config{'PGPSigner'}."\" +verbose=0 language='en' -saft <".$config{'pgptmpf'}.".txt >".$config{'pgptmpf'}.".txt.asc";
		} elsif ($config{'Interactive'}) {
			$PGPCommand = $config{'pgp'}." -z -u \"".$config{'PGPSigner'}."\" +verbose=0 language='en' -saft <".$config{'pgptmpf'}.".txt >".$config{'pgptmpf'}.".txt.asc";
		} else {
			die("$0: Passphrase is unknown!\n");
		}
	} elsif ($PGPVersion eq '5') {
		if ($config{'PathtoPGPPass'}) {
			$PGPCommand = "PGPPASSFD=".$config{'PGPPassFD'}." ".$config{'pgp'}."s -u \"".$config{'PGPSigner'}."\" -t --armor -o ".$config{'pgptmpf'}.".txt.asc -z -f < ".$config{'pgptmpf'}.".txt ".$config{'PGPPassFD'}."<".$config{'PathtoPGPPass'};
		} elsif ($config{'Interactive'}) {
			$PGPCommand = $config{'pgp'}."s -u \"".$config{'PGPSigner'}."\" -t --armor -o ".$config{'pgptmpf'}.".txt.asc -z -f < ".$config{'pgptmpf'}.".txt";
		} else {
			die("$0: Passphrase is unknown!\n");
		}
	} elsif ($PGPVersion eq '6') { # this is untested
		if ($config{'PathtoPGPPass'}) {
			$PGPCommand = "PGPPASSFD=".$config{'PGPPassFD'}." ".$config{'pgp'}." -u \"".$config{'PGPSigner'}."\" -saft -o ".$config{'pgptmpf'}.".txt.asc < ".$config{'pgptmpf'}.".txt ".$config{'PGPPassFD'}."<".$config{'PathtoPGPPass'};
		} elsif ($config{'Interactive'}) {
			$PGPCommand = $config{'pgp'}." -u \"".$config{'PGPSigner'}."\" -saft -o ".$config{'pgptmpf'}.".txt.asc < ".$config{'pgptmpf'}.".txt";
		} else {
			die("$0: Passphrase is unknown!\n");
		}
	} elsif ($PGPVersion =~ m/GPG/io) {
		if ($config{'PathtoPGPPass'}) {
			$PGPCommand = $config{'pgp'}." --digest-algo $config{'digest-algo'} -a -u \"".$config{'PGPSigner'}."\" -o ".$config{'pgptmpf'}.".txt.asc --no-tty --batch --passphrase-fd ".$config{'PGPPassFD'}." ".$config{'PGPPassFD'}."<".$config{'PathtoPGPPass'}." --clearsign ".$config{'pgptmpf'}.".txt";
		} elsif ($config{'Interactive'}) {
			$PGPCommand = $config{'pgp'}." --digest-algo $config{'digest-algo'} -a -u \"".$config{'PGPSigner'}."\" -o ".$config{'pgptmpf'}.".txt.asc --no-secmem-warning --no-batch --clearsign ".$config{'pgptmpf'}.".txt";
		} else {
			die("$0: Passphrase is unknown!\n");
		}
	} else {
		die("$0: Unknown PGP-Version $PGPVersion!");
	}
	return $PGPCommand;
}


#-------- sub postarticle
# postarticle posts your article to your Newsserver.
#
# Receives:
# 	- $ArticleR: A reference to an array containing the article
sub postarticle {
	my ($ArticleR) = @_;

	my $Server = AuthonNNTP();
	my $ServerCod = $Server->code();
	if ($ServerCod == 340) {
		$Server->datasend(@$ArticleR);
		$Server->dataend();
		if (!$Server->ok()) {
			my $ServerMsg = $Server->message();
			$Server->quit();
			die("\n$0: Posting failed! Response from news server:\n", $Server->code(), ' ', $ServerMsg);
		}
		$Server->quit();
	} else {
		die("\n".$0.": Posting failed!\n");
	}
	return;
}


#-------- sub savearticle
# savearticle saves your article to the directory $config{'savedir'}
#
# Receives:
# 	- $ArticleR: A reference to an array containing the article
sub savearticle {
	my ($ArticleR) = @_;
	my $timestamp = timelocal(localtime);
	(my $ng = $Newsgroups) =~ s#^Newsgroups:\s*([^,\s]+).*#$1#i;
	my $gn = join "", map { substr($_,0,1) } (split(/\./, $ng));
	my $filename = $config{'savedir'}."/".$timestamp."-".$gn."-".$$;
	open(my $SH, '>', $filename) or die("$0: can't open $filename: $!\n");
	print $SH @$ArticleR;
	close($SH) or warn "$0: Couldn't close: $!\n";
	return;
}


#-------- sub signarticle
# signarticle signs an article and returns a reference to an array
# 	containing the whole signed Message.
#
# Receives:
# 	- $HeaderR: A reference to a hash containing the articles headers.
# 	- $BodyR: A reference to an array containing the body.
#
# Returns:
# 	- $MessageRef: A reference to an array containing the whole message.
sub signarticle {
	my ($HeaderR, $BodyR) = @_;
	my (@pgphead, @pgpbody, $pgphead, $pgpbody, $signheaders, @signheaders);

	foreach (@{$config{'PGPSignHeaders'}}) {
		if (defined($$HeaderR{lc($_)}) && $$HeaderR{lc($_)} =~ m/^[^\s:]+: .+/o) {
			push @signheaders, $_;
		}
	}

	$pgpbody = join("", @$BodyR);

	# Delete and create the temporary pgp-Files
	unlink $config{'pgptmpf'}.".txt";
	unlink $config{'pgptmpf'}.".txt.asc";
	$signheaders = join(",", @signheaders);

	$pgphead = "X-Signed-Headers: $signheaders\n";
	foreach my $header (@signheaders) {
		if ($$HeaderR{lc($header)} =~ m/^[^\s:]+: (.+?)\n?$/so) {
			$pgphead .= $header.": ".$1."\n";
		}
	}

	unless (substr($pgpbody,-1,1)=~ /\n/ ) {$pgpbody.="\n"};
	open(my $FH, '>', $config{'pgptmpf'} . ".txt") or die("$0: can't open ".$config{'pgptmpf'}.": $!\n");
	print $FH $pgphead, "\n", $pgpbody;
	print $FH "\n" if ($config{'PGPVersion'} =~ m/GPG/io); # workaround a pgp/gpg incompatibility - should IMHO be fixed in pgpverify
	close($FH) or warn "$0: Couldn't close TMP: $!\n";

	# Start PGP, then read the signature;
	`$PGPCommand`;

	open($FH, '<', $config{'pgptmpf'} . ".txt.asc") or die("$0: can't open ".$config{'pgptmpf'}.".txt.asc: $!\n");
	local $/ = "\n".$config{'pgpbegin'}."\n";
	$_ = <$FH>;
	unless (m/\Q$config{'pgpbegin'}\E$/o) {
		unlink $config{'pgptmpf'} . ".txt";
		unlink $config{'pgptmpf'} . ".txt.asc";
		die("$0: ".$config{'pgpbegin'}." not found in ".$config{'pgptmpf'}.".txt.asc\n");
	}
	unlink($config{'pgptmpf'} . ".txt") or warn "$0: Couldn't unlink ".$config{'pgptmpf'}.".txt: $!\n";

	local $/ = "\n";
	$_ = <$FH>;
	unless (m/^Version: (\S+)(?:\s(\S+))?/o) {
		unlink $config{'pgptmpf'} . ".txt.asc";
		die("$0: didn't find PGP Version line where expected.\n");
	}
	if (defined($2)) {
		$$HeaderR{$config{'pgpheader'}} = $1."-".$2." ".$signheaders;
	} else {
		$$HeaderR{$config{'pgpheader'}} = $1." ".$signheaders;
	}
	do {			# skip other pgp headers like
		$_ = <$FH>;	# "charset:"||"comment:" until empty line
	} while ! /^$/;

	while (<$FH>) {
		chomp;
		last if /^\Q$config{'pgpend'}\E$/;
		$$HeaderR{$config{'pgpheader'}} .= "\n\t$_";
	}
	$$HeaderR{$config{'pgpheader'}} .= "\n" unless ($$HeaderR{$config{'pgpheader'}} =~ /\n$/s);

	$_ = <$FH>;
	unless (eof($FH)) {
		unlink $config{'pgptmpf'} . ".txt.asc";
		die("$0: unexpected data following ".$config{'pgpend'}."\n");
	}
	close($FH);
	unlink $config{'pgptmpf'} . ".txt.asc";

	my $tmppgpheader = $config{'pgpheader'} . ": " . $$HeaderR{$config{'pgpheader'}};
	delete $$HeaderR{$config{'pgpheader'}};

	@pgphead = ();
	foreach my $header (@{$config{PGPorderheaders}}) {
		if ($$HeaderR{$header} && $$HeaderR{$header} ne "\n") {
			push(@pgphead, "$$HeaderR{$header}");
			delete $$HeaderR{$header};
		}
	}

	foreach my $header (keys %$HeaderR) {
		if ($$HeaderR{$header} && $$HeaderR{$header} ne "\n") {
			push(@pgphead, "$$HeaderR{$header}");
			delete $$HeaderR{$header};
		}
	}

	push @pgphead, ("X-PGP-Hash: " . $config{'digest-algo'} . "\n") if (defined($config{'digest-algo'}));
	push @pgphead, ("X-PGP-Key: " . $config{'PGPSigner'} . "\n"), $tmppgpheader;
	undef $tmppgpheader;

	@pgpbody = split(/$/m, $pgpbody);
	my @pgpmessage = (@pgphead, "\n", @pgpbody);
	return \@pgpmessage;
}

sub version {
	print $pname." ".$version."\n";
	return;
}

sub usage {
	version();
	print "Usage: ".$pname." [OPTS] < article\n";
	print "  -a string  set Approved:-header to string\n";
	print "  -c string  set Control:-header to string\n";
	print "  -d string  set Distribution:-header to string\n";
	print "  -e string  set Expires:-header to string\n";
	print "  -f string  set From:-header to string\n";
	print "  -n string  set Newsgroups:-header to string\n";
	print "  -o string  set Organization:-header to string\n";
	print "  -p port    use port as NNTP port [default=".$config{'NNTPPort'}."]\n";
	print "  -r string  set Reply-To:-header to string\n";
	print "  -s string  save signed article to directory string instead of posting\n";
	print "  -t string  set Subject:-header to string\n";
	print "  -v         show version\n";
	print "  -w string  set Followup-To:-header to string\n";
	print "  -x string  set Path:-header to string\n";
	print "  -H         show help\n";
	print "  -L         do not add Cancel-Lock: / Cancel-Key: headers\n";
	print "  -R         disallow control messages\n";
	print "  -S         do not append " . $config{'sig_path'} . "\n";
	print "  -X         do not sign article\n";
	print "  -Y         force authentication on connect\n";
	exit 0;
}

__END__

=head1 NAME

tinews.pl - Post and sign an article via NNTP

=head1 SYNOPSIS

B<tinews.pl> [B<OPTIONS>] E<lt> I<input>

=head1 DESCRIPTION

B<tinews.pl> reads an article on STDIN, signs it via B<pgp>(1) or
B<gpg>(1) and posts it to a newsserver.

If the article contains To:, Cc: or Bcc: headers and mail-actions are
configured it will automatically add a "Posted-And-Mailed: yes" header
to the article and send out the mail-copies.

If a Cancel-Lock secret file is defined it will automatically add a
Cancel-Lock: (and Cancel-Key: if required) header.

The input should have unix line endings (<LF>, '\n').

=head1 OPTIONS
X<tinews, commandline options>

=over 4

=item -B<a> C<Approved> | --B<approved> C<Approved>
X<-a> X<--approved>

Set the article header field Approved: to the given value.

=item -B<c> C<Control> | --B<control> C<Control>
X<-c> X<--control>

Set the article header field Control: to the given value.

=item -B<d> C<Distribution> | --B<distribution> C<Distribution>
X<-d> X<--distribution>

Set the article header field Distribution: to the given value.

=item -B<e> C<Expires> | --B<expires> C<Expires>
X<-e> X<--expires>

Set the article header field Expires: to the given value.

=item -B<f> C<From> | --B<from> C<From>
X<-f> X<--from>

Set the article header field From: to the given value.

=item -B<n> C<Newsgroups> | --B<newsgroups> C<Newsgroups>
X<-n> X<--newsgroups>

Set the article header field Newsgroups: to the given value.

=item -B<o> C<Organization> | --B<organization> C<Organization>
X<-o> X<--organization>

Set the article header field Organization: to the given value.

=item -B<p> C<port> | --B<port> C<port>
X<-p> X<--port>

use C<port> as NNTP-port

=item -B<r> C<Reply-To> | --B<replyto> C<Reply-To>
X<-r> X<--replyto>

Set the article header field Reply-To: to the given value.

=item -B<s> F<directory> | --B<savedir> F<directory>
X<-s> X<--savedir>

Save signed article to directory F<directory> instead of posting.

=item -B<t> C<Subject> | --B<subject> C<Subject>
X<-t> X<--subject>

Set the article header field Subject: to the given value.

=item -B<v> | --B<version>
X<-v> X<--version>

Show version.

=item -B<w> C<Followup-To> | --B<followupto> C<Followup-To>
X<-w> X<--followupto>

Set the article header field Followup-To: to the given value.

=item -B<x> C<Path> | --B<path> C<Path>
X<-x> X<--path>

Set the article header field Path: to the given value.

=item -B<H> | --B<help>
X<-H> X<--help>

Show help-page.

=item -B<L> | --B<no-canlock>
X<-L> X<--no-canlock>

Do not add Cancel-Lock: / Cancel-Key: headers.

=item -B<R> | --B<no-control>
X<-R> X<--no-control>

Restricted mode, disallow control-messages.

=item -B<S> | --B<no-signature>
X<-s> X<--no-signature>

Do not append F<$HOME/.signature>.

=item -B<X> | --B<no-sign>
X<-X> X<--no-sign>

Do not sign the article.

=item -B<Y> | --B<force-auth>
X<-Y> X<--force-auth>

Force authentication on connect even if not required by the server.

=item -B<A> -B<V> -B<W>
X<-A> X<-V> X<-W>

These options are accepted for compatibility reasons but ignored.

=item -B<h> | --B<headers>
X<-h> X<--headers>

These options are accepted for compatibility reasons but ignored.

=item -B<O> | --B<no-organization>
X<-O> X<--no-organization>

These options are accepted for compatibility reasons but ignored.

=item -B<D> | -B<N> | --B<debug>
X<-D> X<-N> X<--debug>

These options are accepted but do not have any functionality yet.

=back

=head1 EXIT STATUS

The following exit values are returned:

=over 4

=item S< 0>

Successful completion.

=item S<!=0>

An error occurred.

=back

=head1 ENVIRONMENT
X<tinews, environment variables>

=over 4

=item B<$NNTPSERVER>
X<$NNTPSERVER> X<NNTPSERVER>

Set to override the NNTP server configured in the source.

=item B<$NNTPPORT>
X<$NNTPPORT> X<NNTPPORT>

The NNTP TCP-port to post news to. This variable only needs to be set if the
TCP-port is not 119 (the default). The '-B<p>' command-line option overrides
B<$NNTPPORT>.

=item B<$PGPPASS>
X<$PGPPASS> X<PGPPASS>

Set to override the passphrase configured in the source (used for
B<pgp>(1)-2.6.3).

=item B<$PGPPASSFILE>
X<$PGPPASSFILE> X<PGPPASSFILE>

Passphrase file used for B<pgp>(1) or B<gpg>(1).

=item B<$SIGNER>
X<$SIGNER> X<SIGNER>

Set to override the user-id for signing configured in the source. If you
neither set B<$SIGNER> nor configure it in the source the contents of the
From:-field will be used.

=item B<$REPLYTO>
X<$REPLYTO> X<REPLYTO>

Set the article header field Reply-To: to the return address specified by
the variable if there isn't already a Reply-To: header in the article.
The '-B<r>' command-line option overrides B<$REPLYTO>.

=item B<$ORGANIZATION>
X<$ORGANIZATION> X<ORGANIZATION>

Set the article header field Organization: to the contents of the variable
if there isn't already a Organization: header in the article. The '-B<o>'
command-line option overrides B<$ORGANIZATION>.

=item B<$DISTRIBUTION>
X<$DISTRIBUTION> X<DISTRIBUTION>

Set the article header field Distribution: to the contents of the variable
if there isn't already a Distribution: header in the article. The '-B<d>'
command-line option overrides B<$DISTRIBUTION>.

=back

=head1 FILES

=over 4

=item F<pgptmp.txt>

Temporary file used to store the reformatted article.

=item F<pgptmp.txt.asc>

Temporary file used to store the reformatted and signed article.

=item F<$PGPPASSFILE>

The passphrase file to be used for B<pgp>(1) or B<gpg>(1).

=item F<$HOME/.signature>

Signature file which will be automatically included.

=item F<$HOME/.cancelsecret>

The passphrase file to be used for Cancel-Locks. This feature is turned
off by default.

=item F<$HOME/.newsauth>

"nntpserver password [user]" pairs for NNTP servers that require
authorization. Any line that starts with "#" is a comment. Blank lines are
ignored. This file should be readable only for the user as it contains the
user's uncrypted password for reading news. First match counts. If no
matching entry is found F<$HOME/.nntpauth> is checked.

=item F<$HOME/.nntpauth>

"nntpserver user password" pairs for NNTP servers that require
authorization. First match counts. Lines starting with "#" are skipped and
blank lines are ignored. This file should be readable only for the user as
it contains the user's uncrypted password for reading news.
F<$HOME/.newsauth> is checked first.

=item F<$XDG_CONFIG_HOME/tinewsrc> F<$HOME/.config/tinewsrc> F<$HOME/.tinewsrc>

"option=value" configuration pairs. Lines that start with "#" are ignored.
If the file contains uncrypted passwords (e.g. NNTPPass or PGPPass), it
should be readable for the user only.

=back

=head1 SECURITY

If you've configured or entered a password, even if the variable that
contained that password has been erased, it may be possible for someone to
find that password, in plaintext, in a core dump. In short, if serious
security is an issue, don't use this script.

=head1 NOTES

B<tinews.pl> is designed to be used with B<pgp>(1)-2.6.3,
B<pgp>(1)-5, B<pgp>(1)-6 and B<gpg>(1).

B<tinews.pl> requires the following standard modules to be installed:
B<Getopt::Long>(3pm), B<Net::NNTP>(3pm), B<Time::Local>(3pm) and
B<Term::Readline>(3pm).

If the Cancel-Lock feature is enabled the following additional modules
must be installed: B<MIME::Base64>(3pm), B<Digest::SHA>(3pm) or
B<Digest::SHA1>(3pm) and B<Digest::HMAC_SHA1>(3pm)

=head1 AUTHOR

Urs Janssen E<lt>urs@tin.orgE<gt>,
Marc Brockschmidt E<lt>marc@marcbrockschmidt.deE<gt>

=head1 SEE ALSO

B<pgp>(1), B<gpg>(1), B<pgps>(1), B<Digest::HMAC_SHA1>(3pm),
B<Digest::SHA>(3pm), B<Digest::SHA1>(3pm), B<Getopt::Long>(3pm),
B<MIME::Base64>(3pm), B<Net::NNTP>(3pm), B<Time::Local>(3pm),
B<Term::Readline>(3pm)

=cut
