#!/bin/sh
#
# mail->fax gateway
#
#
# limited usability: only exactly one person, pete@54.rahul.net,
# may use it.
#

# get phone number
if [ $# -ne 1 ]
then
    echo "faxmail <faxnumber>" >&2
    exit 1
fi
faxphone=$1

#
# copy mail (on stdin) to separate files for header and body,
# extracting "From:" and "Reply-To:" headers on the way
#
head=/tmp/mf$$.head
body=/tmp/mf$$.body
fax=/tmp/mf$$.fax
tmp=/tmp/mf$$.tmp
#
eval `awk ' function getaddr(line) {
		b = index( line, "<" );
		if ( b != 0 )
		{
		    f=substr( line, b+1 );
		    return substr( f, 1, index( f, ">" ) -1 );
		}
		split( line, broken );
		return broken[2];
	    }
	    BEGIN { header=1; from=""; replyto=""; subject=""; fullfrom="" }
	    NF == 0 { if ( header ) { header = 0; next; } }
	            { if ( header ) print >> "'$head'";
                               else print >> "'$body'" }
	    /^From:[ \t]/ \
                    { if ( header ) from=getaddr($0); }
	    /^Reply-To:[ \t]/ \
                    { if ( header ) replyto=getaddr($0); }
	    /^Subject:[ \t]/ \
                    { if ( header ) subject=substr($0, 10); }
	    /^From:[ \t]/ \
                    { if ( header ) fullfrom=substr($0, 7); }
	    END { printf "subject=\"%s\"; from=\"%s\"; replyto=\"%s\"; fullfrom=\"%s\"\n", \
			 subject, from, replyto, fullfrom }
           ' - `

# determine reply address
mailto=${replyto:-$from}

test -w /tmp/mf.adrlog && echo "$from $replyto -> $mailto" >>/tmp/mf.adrlog

# which is my host???
whoami=`hostname 2>/dev/null` || whoami=`uname -n`

# authentication: base on $from and $faxphone

# very simple, for now
if expr "$from" : "gert@.*.muc.de" >/dev/null || \
   expr "$from" : ".*@RockyMountain.rahul.net" >/dev/null
#if expr "$from" : "gert@.*.muc.de" >/dev/null 
then
#
# ok. Authentication granted. Queue fax.
#
    echo "faxspool -f $mailto $faxphone $body" >>/tmp/mf.test

    cat <<EOF >$fax

    FAX FROM: $fullfrom
          TO: $faxphone
     SUBJECT: $subject

    This fax was converted automatically from an electronic mail, so 
    please don't wonder too much about the unusual form. Thanks.

    If you have any questions about it, contact Gert Doering, Muenchen,
    telephone ++49-89-3243228.


    --- original message text follows ---

EOF
    cat $body >>$fax

    faxspool -f "$mailto" -F "Electronic Mail Gateway" $faxphone $fax >$tmp 2>&1

    ( cat <<EOF
To: $mailto
Cc: postmaster
From: root@$whoami (The Automatic Fax Robot)
Subject: Your fax to $faxphone

Dear user,

your fax to $faxphone has been queued. Upon delivery (or failure)
you will be notified.

regards,
	your fax daemon

--- queue log: ---
EOF
    cat $tmp
    ) | /usr/sbin/sendmail -t
else
#
# fax denied
#
    ( cat <<EOF
To: $mailto
CC: postmaster
From: root@$whoami (The Automatic Fax Robot)
Subject: Your fax to $faxphone

Dear user,

you are not authorized to use greenie's mail-to-fax gateway service.

If you want to use it, please contact the system administrator,
root@$whoami.

Thanks,
	your fax robot

------ your mail follows -------
EOF
    cat $head
    echo ""
    head -50 $body
    ) | /usr/sbin/sendmail -t
fi

# clean up
rm -f $head $body $fax $tmp

exit 0
