GNARWL(8)
GNARWL(8)
NAME
gnarwl - GNU Neat Autoreply With LDAP
SYNOPSIS
gnarwl [-h] [-c <cfgfile>] [-a <address>] [-s <address>]
DESCRIPTION
gnarwl is an email autoresponder, intended to be a succes-
sor to the old
vaction(1) program. Since a modern mailserver, usually
serves hundreds
(or even thousands) of mailaccounts, it is not
sensible to give
(untrusted) users shell access so they may create/maintain
the .forward
file, required by vacation(1).
With gnarwl , all user-suplied data is stored within an
LDAP database,
so there are no per user ".forward" files (or even home-
dirs) needed.
Configuration is conveniently done via one systemwide con-
figfile.
Like the old vacation(1) program, gnarwl accepts incomming
mail through
stdin, and will send outgoing mail via an external MTA (it
even main-
tains basic commandline compatibility, so it may be used
as a drop in
replacement).
Several gdbm databases are maintained, in order to make
sure, a) mail
does not bounce back and force between gnarwl and an-
other automated
MUA, b) mailing lists will not be bothered and c)
specifc local
addresses may never produce automatic replies. All
these database
files may be managed using the damnit(8) program.
OPTIONS
-c <cfgfile>
Use a different configfile than the one, compiled
in.
-a <alias>
Force <address> as receiving address.
-s <address>
Force <address> as sending address.
-h Print usage information.
CONFIGURATION
gnarwl typically uses one global configurationfile, but a
per user set-
up is also possible using the -c commandline switch. The
following key-
words are recognized in the configfile:
map_sender <macroname>
Binds a macroname (case insensitive), refering to
the sender of
an incomming email. Defaults to "$sender".
map_receiver <macroname>
Binds a macroname (case insensitive),
refering to the
receiver(s) of an incomming email. Defaults to
"$receiver".
map_subject <macroname>
Binds a macroname (case insensitive), refering to
the subject of
an incomming email. Defaults to "$subject".
map_field <ldapattribute> <macroname>
Binds a macroname (case insensitive), refering to a
field in the
resultset, returned by the database. There are no
defaults for
this directive.
server <address>
Address of the databaseserver to query. Defaults to
localhost.
port <portnumber>
Port, the LDAP server listens on. Defaults to 389.
scope <base|one|sub>
The scope used for searching the database. Default
is ";sub".
login <string>
Destinguished name to bind with to the LDAP data-
base. Default is
to bind anonymously.
password <string>
Password to use for binding to the LDAP database.
If a password
is required to access the server, then the con-
figfile should
belong to the gnarwl user and have file permission
0400.
base <destinguished name>
Entrypoint of the search. There is no default for
this direc-
tive, it must be supplied by the administrator.
protocol <0|2|3>
Select protocol to bind to the ldapserver. The
default is 0,
which means "autodetect".
queryfilter <ldap queryfilter>
Search pattern to match against the database.
Defaults to:
"(&(mail=$recepient)(vacationActive=TRUE)".
result <ldap attribute>
The name of the attribute, that is to be taken as
the emailbody.
The content of this field will be pasted in be-
tween the data
found via forceheader and forcefooter directives.
Afterwards all
remaining macros are expanded in the order of dec-
laration, and
the result will be piped through to the MTA.
blockfiles <directory>
The directory, where gnarwl stores it's block-
files. These files
are required to keep track on who was sent an au-
tomatic reply.
Default
is:
"/tmp/buildd/gnarwl-3.6.dfsg/debian/gnar-
wl/var/lib/gnarwl/block/".
umask <mode>
What permission to give newly generated data-
base files. The
default is 0600.
blockexpire <number>
How long (in hours) to block a certain sender/re-
cepient combo.
Default is 48 hours. Setting <number> to 0 dis-
ables the feature
(not recommended). No blockfiles are read/written
in this case.
maxreceivers <number>
Ignore incomming email, specifying too many receiv-
ing addresses.
It does not matter, whether these are local or
not, as gnarwl
doesn't know domains. Default is 256.
maxheader <number>
Ignore incomming email with more than this num-
ber of header
lines. Lines are counted before unfolding them, so
a folded line
really counts as at least two lines. Default is
256.
badheaders <filename>
Path to a database file, containing matching pat-
terns for the
mailheader. If an entry stored in this file
matches a line in
the header exactly, then this mail will be ignored
by gnarwl is
deactivated by default.
blacklist <filename>
Pointer to a database file, containing emailad-
dresses, gnarwl is
not allowed to generate automatic replies for (use-
ful to prevent
automatic replies from addresses, which are
shared by several
people). This feature is deactivated by default.
forceheader <filename>
Path to a text file, containing a standardized
header, that is
to be pasted in front of every outgoing mail.
This file should
end with a single empty line. Otherwise it is as-
sumed, that the
users are allowed to continue the header and
will provide the
separating empty line themselves. Default is not
to force any-
thing (that is: The user has to supply the
header in the
"result" attribute).
forcefooter <filename>
Path to a text file, containing a standardized
footer, that is
to be appended at the end of every generated mail.
Default is to
not to force anything.
mta <prog> [<args>]
Specify MTA for sending mail. It must be able to
accept mail on
STDIN. Default is "/usr/sbin/sendmail".
charset <encoding>
LDAP stores text in unicode, which is ok, as
long as outgoing
mail doesn't contain any non ASCII characters.
However, locale
specific characters (like german umlaute) end
up as strange
glyphs. With the "charset" directive, gnarwl tries
to convert
these to the correct symbols. The <encoding> argu-
ment must con-
tain a string recognized by iconv(3). Default is
not to try to
convert anything (assume US-ASCII charset / MIME
encoded mail).
recvheader <string>
A whitespace separated list of headers (case does
not matter),
which may contain receiving addresses. Defaults to:
"To Cc".
loglevel <0|1|2|3>
Specifies what to send to the syslog. A higher
loglevel automat-
ically includes all lower loglevels (see section
syslog for more
information).
SYSLOG
Since gnarwl is not meant to be invoked by anything but
the mailsystem,
it'll never print out messages to the systemconsole, but
logs them via
syslog(3), using the facility "mail". A log line is always
of the fol-
lowing format:
<level>/<origin> <message>
The <level> field indicates the severity of the message,
it corresponds
to the "loglevel" config directive. Possible values are:
CRIT (loglevel 0)
Critical messages. gnarwl cannot continue and will
die with a
non-zero exit code. This usually causes the mail-
system to bounce
mail.
WARN (loglevel 1)
A warning. gnarwl can will continue, but
not with the
full/intended functionality.
INFO (loglevel 2)
Status information. A message in the INFO
loglevel indicates
normal behaviour.
DEBUG (loglevel 3)
Debugging information. gnarwl will log a lot of
information on
how mail is processed.
The <origin> field gives a short hint about what caused
the log entry
in question, while <message> contains a short description
of what actu-
ally happened.
AUTHOR
Patrick Ahlbrecht <p.ahlbrecht@billiton.de>
SEE ALSO
vacation(1), postfix(1), iconv(1), damnit(8), rfc822
FILES
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/etc/gnarwl.cfg
main configuration file.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/.forward
forward file for the mailsystem.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/blacklist.db
gnarwl won't send an autoreply for anyone whose
emailaddress is
listed herin.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/badheaders.db
gnarwl will ignore mail, it is able to match a
headerline with
an entry in this file. Case is significant, no
wildcards are
expanded.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/header.txt
Standard header to paste in front of every outgoing
mail.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/footer.txt
Standard footer to append to every outgoing mail.
/tmp/buildd/gnarwl-3.6.dfsg/debian/gnarwl/var/lib/gnarwl/block/*
block files.
GNAR-
WL(8)