#!/usr/bin/perl

# Approve Majordomo requests or "resend" bounces.
#
# Given arguments, approves the requests in those files;
# given no arguments, reads standard input.
#
# If the "Subject: " line is "APPROVE <list>", the message is treated as
# a request for approval from Majordomo.  An appropriate command is generated
# and mailed to Majordomo to approve the request.
#
# If the "Subject: " line is "BOUNCE <list>: <reason>", the message is treated
# as a posting rejected by "resend" for some reason, and is reformatted with
# appropriate "Approved:" headers to cause it to succeed, then resubmitted
# for posting.
#
# Assumes that the "approve" password for each list is the same as the
# "approval" password used by "resend", and that this password is stored
# in a file called ".majordomo" in the user's home directory, in the
# following format:
# 
# 	List		Password	Majordomo-Address
# 
# Assumes that the "Majordomo-Address" field is an Internet-style 
# "something@somewhere" address, and that postings for "List" should
# be sent to "List@somewhere".
#
# Here's an example of what a .majordomo file should look like:
# 
# 	this-list	passwd1		Majordomo@This.COM
# 	other-list	passwd2		Majordomo@Other.GOV
# 
# If, for instance, /tmp/request contains a standard request from Majordomo
# to a list manager, such as:
#
#	From: Majordomo@This.COM
#	To: this-list-approval@This.COM
#
#	User@Fubar.COM (Joe User) requests you approve the following:
#
#		subscribe this-list User@Fubar.COM (Joe User)
#
#	If you approve, send a line such as the following to Majordomo@This.COM:
#
#		approve PASSWD subscribe this-list User@Fubar.COM (Joe User)
# 
# Then, if you run "approve /tmp/request" or "approve < /tmp/request", the
# following message will be sent to Majordomo@This.COM:
#
#	To: Majordomo@This.COM
#
# 	approve passwd1 subscribe this-list User@Fubar.COM (Joe User)
# 
# Brent Chapman                                   Great Circle Associates
# Brent@GreatCircle.COM                           1057 West Dana Street
# +1 415 962 0841                                 Mountain View, CA  94041

# $Source: /sources/cvsrepos/majordomo/approve,v $
# $Revision: 1.15 $
# $Date: 1997/04/05 19:18:36 $
# $Author: cwilson $
# $State: Exp $
#
# $Locker:  $

$MAILER = '/usr/lib/sendmail' if -x '/usr/lib/sendmail';
$MAILER = '/usr/sbin/sendmail' if -x '/usr/sbin/sendmail';

die "Couldn't find a sendmail to invoke, please define!" 
    if !$MAILER;


require "getopts.pl";

&Getopts("df:") ||
    die("USAGE: approve [-f <config-file>] [-d] [<file> ...]\nStopped");

if (!defined($opt_f)) {
    $opt_f = "$ENV{HOME}/.majordomo";
}

&read_config();

# Read the headers.  Look at the "Reply-To:" header to figure out where to
# respond to.  Look at the "Subject:" header to figure out if this is an
# APPROVE or a BOUNCE request.

if (@ARGV) {
    foreach $file (@ARGV) {
	open(FILE, $file) || (warn("can't open \"$file\"; skipping"), next);
	&process_file(FILE);
	close(FILE);
    }
} else {
    &process_file(STDIN);
}

exit(0);

sub process_file {
    local($FILE) = shift;
    local($reply_to);
    local($subject);
    local($request);
    local($list);

    while (<$FILE>) {
	s/\n$//;
	if (/^reply-to:/i) {
	    s/^\S*:\s+//;
	    $reply_to = $_;
	    $reply_to =~ tr/A-Z/a-z/;
	    next;
	}
	if (/^subject:/i) {
	    s/^\S*:\s+//;
	    $subject = $_;
	    $subject =~ tr/A-Z/a-z/;
	    ($request, $list) = split(/\s/, $subject, 2);
	    $list =~ s/:.*//;
	    next;
	}
	if (/^$/) {
	    last;
	}
    }

    # we've read the headers, so we should know now if this is an "APPROVE"
    # or a "BOUNCE" that we're processing.

    if ($request eq "approve") { &process_approve($FILE); }
    elsif ($request eq "bounce") { &process_bounce($FILE); }
    else {
	warn("unknown request type '$request' in file '$file'; skipping");
    }
}

sub process_approve {
    local($FILE) = shift;
    while (<$FILE>) {
	if ((/^\tsubscribe\s/) || (/^\tunsubscribe\s/)) {
	    if (!defined($reply_to)) {
		warn("No \"Reply-To:\"; exiting");
		exit(1);
	    }
	    s/^\t//;
	    split;
	    $list = $_[1];
	    $list =~ tr/A-Z/a-z/;
	    $passwd = $passwd{"$list\@$reply_to"};
	    if (! $passwd) {
		warn("no password for list $list; skipping \"$_\"");
		next;
	    }
	    if (defined($opt_d)) {
		open(MAIL, ">&STDOUT");
		print MAIL "-" x 20, "\n";
	    } else {
		open(MAIL, "|$MAILER $reply_to") ||
		    die ("open(\"|$MAILER ...\"): $!");
	    }

	    print MAIL "To: $reply_to\n\n";
	    print MAIL "approve $passwd $_";
	    close(MAIL);
	    last;
	}
    }
    print STDERR "Mailed approved command to $list list.\n"
	unless defined $opt_d;
}

sub process_bounce {
    local($FILE) = shift;
    local ($from_skipped);

    # we've already skipped the header, so set up to approve the message

    # first, figure out where to send it
    if (defined($reply_to)) {
	# if there's a "Reply-To:" field set, use it.
	$post_to = $reply_to;
    } elsif ($list =~ /\@/) {
	# if the list name already appears fully qualified, use it
	$post_to = $list;
    } else {
	# Well, can we figure it out?
	if ($site{$list} eq "MULTIPLE") {
	    warn("Can't distinguish between multiple lists named '$list'\nSkipping '$file'");
	    return;
	} else {
	    $post_to = $list . "\@" . $site{$list};
	}
    }

    if (!defined($passwd{$list})) {
	warn "Can't find password for list $list, Stopped";
	return;
    }

    if (defined($opt_d)) {
	open(MAIL, ">&STDOUT");
	print MAIL "-" x 20, "\n";
	print MAIL "To: $post_to\n\n";
    } else {
	open(MAIL, "|$MAILER $post_to") || die("open(\"|$MAILER...\"): $!");
    }

    print MAIL "Approved: $passwd{$list}\n";

    while (<$FILE>) {
	if (/^>?From / && ! defined($from_skipped)) {
	    # Skip any initial "From " or ">From " line
	    $from_skipped = 1;
	    next;
	}
	s/^~/~~/;
	print MAIL $_;
    }
    close(MAIL);
    print STDERR "Mailed approved message to $list list.\n";
}

sub read_config {
    local($l);
    local($p);
    local($m);
    local($s);
    open(CONF, $opt_f) || die("open(CONF, \"$opt_f\"): $!");
    while (<CONF>) {
	s/\n$//;
	s/#.*//;
	if (/^$/) { next; }
	split;
	$l = $_[0];	$l =~ tr/A-Z/a-z/;	# list
	$p = $_[1];				# password
	$m = $_[2];	$m =~ tr/A-Z/a-z/;	# majordomo@site
	split(/\@/, $m);
	$s = $_[1];	$s =~ tr/A-Z/a-z/;	# site

	$passwd{$l} = $p;
	$passwd{"$l\@$m"} = $p;
	$passwd{"$l\@$s"} = $p;
	if (defined($site{$l})) {
	    # if it's already defined, there's more than one list by this name
	    $site{$l} = "MULTIPLE";
	} else {
	    $site{$l} = $s;
	}
    }
    close(CONF);
}