.TH qmail-mfrules 8
.SH NAME
qmail-mfrules \- prepare mfrules for qmail-smtpd
.SH SYNOPSIS
.B qmail-mfrules
.SH DESCRIPTION
.B qmail-mfrules
reads the addresses provided in
.BR /var/qmail/control/mailfromrules ,
converts them into lowercase, and writes them into
.B /var/qmail/control/mailfromrules.cdb
in a binary format suited
for quick access by
.BR qmail-smtpd .

If there is a problem with
.BR control/mailfromrules ,
.B qmail-mfrules
complains and leaves
.B control/mailfromrules.cdb
alone.

.B qmail-mfrules
ensures that
.B control/mailfromrules.cdb
is updated atomically,
so
.B qmail-smtpd
never has to wait for
.B qmail-mfrules
to finish.
However,
.B qmail-mfrules
makes no attempt to protect against two simultaneous updates of
.BR control/mailfromrules.cdb .

The binary
.B control/mailfromrules.cdb
format is portable across machines.

.SH "RULE FORMAT"
A rule is one line. A file containing rules may also contain comments: lines
beginning with # are ignored. All addresses are evaluated case-insensitive.

Each rule contains an address, a colon, and a list of strings separated by 
commas to be used for 'Mail From: Address Verification' (MAV). When
.BR qmail-smtpd (8)
receives a connection from that address, it checks whether the received 
envelope sender address correspondes with a MAV string (from the right 
to the left). 
The MAV string for an address may be NULL in order to allow any envelope
sender address. NULLSENDER envelope addresses are not subject of the MAV.

.SH ADDRESSES
.BR qmail-smtpd (8)
looks for rules with various addresses in the following order:
.IP 1
$TCPREMOTEINNFO, if $TCPREMOTEINFO is set (e.g. by SMTP Authentication);
.IP 2.
$TCPREMOTEINFO@$TCPREMOTEIP, if $TCPREMOTEINFO is set;
.IP 3.
$TCPREMOTEINFO@=$TCPREMOTEHOST, if $TCPREMOTEINFO is set and $TCPREMOTEHOST is
set;
.IP 4.
$TCPREMOTEIP;
.IP 5.
=$TCPREMOTEHOST, if $TCPREMOTEHOST is set;
.IP 6.
shorter and shorter prefixes of $TCPREMOTEIP ending with a dot;
.IP 7.
shorter and shorter suffixes of $TCPREMOTEHOST starting with a dot, preceded
by =, if $TCPREMOTEHOST is set; and finally
.IP 8.
=, if $TCPREMOTEHOST is set.
.P
.BR qmail-smtpd (1)
employes the first matching rule for the MAV check. You should use the
.B -p
option to
.BR tcpserver (1)
if you rely on $TCPREMOTEHOST here.

For example, here are some rules:

     jsmith@virtualdomain.com:john.smith@virtualdomain.com
     joe@18.23.0.32:joe@example.com
     18.23.0.32:@example.com
     =.heaven.mil:god@heaven.mil,st.peter@heaven.mil,-angles@heaven.mil
     127.:localhost


.SH ADDRESS RANGES
.B qmail-smtpd
treats 1.2.3.37-53:ins as an abbreviation for the rules 1.2.3.37:ins,
1.2.3.38:ins, and so on up through 1.2.3.53:ins. Similarly, 10.2-3.:ins is an
abbreviation for 10.2.:ins and 10.3.:ins.

.SH "SEE ALSO"
qmail-smtpd(8)