NEW SENDMAIL CONFIGURATION FILES
Eric Allman <eric@CS.Berkeley.EDU>
@(#)README 8.27 (Berkeley) 3/12/94
This document describes the sendmail configuration files being used
at Berkeley. These use features in the new (R8) sendmail, and although
there is an ``OLDSENDMAIL'' mode, they haven't really been tested on
old versions of sendmail and cannot be expected to work well.
These configuration files are probably not as general as previous
versions, and don't handle as many of the weird cases automagically.
I was able to simplify by them for two reasons. First, the network
has become more consistent -- for example, at this point, everyone
on the internet is supposed to be running a name server, so hacks to
handle NIC-registered hosts can go away. Second, I assumed that a
subdomain would be running SMTP internally -- UUCP is presumed to be
a long-haul protocol. I realize that this is not universal, but it
does describe the vast majority of sites with which I am familiar,
including those outside the US.
Of course, the downside of this is that if you do live in a weird
world, things are going to get weirder for you. I'm sorry about that,
but at the time we at Berkeley had a problem, and it seemed like the
right thing to do.
This package requires a post-V7 version of m4; if you are running the
4.2bsd, SysV.2, or 7th Edition version, I suggest finding a friend with
a newer version. You can m4-expand on their system, then run locally.
SunOS's /usr/5bin/m4 or BSD-Net/2's m4 both work. GNU m4 version 1.1
also works. Unfortunately, I'm told that the M4 on BSDI 1.0 doesn't
work -- you'll have to use a Net/2 or GNU version.
IF YOU DON'T HAVE A BERKELEY MAKE, don't despair! Just run
"m4 foo.mc > foo.cf" -- that should be all you need. There is also
a fairly crude (but functional) Makefile.dist that works on the
old version of make.
To get started, you may want to look at tcpproto.mc (for TCP-only
sites), uucpproto.mc (for UUCP-only sites), and clientproto.mc (for
clusters of clients using a single mail host). Others are versions
that we use at Berkeley, although not all are in current use. For
example, ucbarpa has gone away, but I've left ucbarpa.mc in because
it demonstrates some interesting techniques.
I'm not pretending that this README describes everything that these
configuration files can do; clever people can probably tweak them
to great effect. But it should get you started.
*******************************************************************
*** BE SURE YOU CUSTOMIZE THESE FILES! They have some ***
*** Berkeley-specific assumptions built in, such as the name ***
*** of our UUCP-relay. You'll want to create your own domain ***
*** description, and use that in place of domain/Berkeley.m4. ***
*******************************************************************
+--------------------------+
| INTRODUCTION AND EXAMPLE |
+--------------------------+
Configuration files are contained in the subdirectory "cf", with a
suffix ".mc". They must be run through "m4" to produce a ".cf" file.
Let's examine a typical .mc file (cf/cs-exposed.mc):
divert(-1)
#
# Copyright (c) 1983 Eric P. Allman
# Copyright (c) 1988 The Regents of the University of California.
# All rights reserved.
#
# Redistribution and use in source and binary forms are permitted
# provided that the above copyright notice and this paragraph are
# duplicated in all such forms and that any documentation,
# advertising materials, and other materials related to such
# distribution and use acknowledge that the software was developed
# by the University of California, Berkeley. The name of the
# University may not be used to endorse or promote products derived
# from this software without specific prior written permission.
# THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
# WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
#
The divert(-1) will delete the crud in the resulting output file.
The copyright notice is what your lawyers require. Our lawyers require
the one that I've included in my files. A copyleft is a copyright by
another name.
The next line MUST be
include(`../m4/cf.m4')
This will pull in the M4 macros you will need to make sense of
everything else. As the saying goes, don't think about it, just
do it. If you don't do it, don't bother reading the rest of this
file.
VERSIONID(`<SCCS or RCS version id>')
VERSIONID is a macro that stuffs the version information into the
resulting file. We use SCCS; you could use RCS, something else, or
omit it completely. This is not the same as the version id included
in SMTP greeting messages -- this is defined in m4/version.m4.
DOMAIN(cs.exposed)
This example exposes the host inside of the CS subdomain -- that is,
it doesn't try to hide the name of the workstation to the outside
world. Changing this to DOMAIN(cs.hidden) would have made outgoing
messages refer to "<username>@CS.Berkeley.EDU" instead of using the
local hostname. Internally this is effected by using
"MASQUERADE_AS(CS.Berkeley.EDU)".
MAILER(smtp)
These describe the mailers used at the default CS site site. The
local mailer is always included automatically.
+--------+
| OSTYPE |
+--------+
Note that cf/cs-exposed.mc omits an OSTYPE macro -- this assumes
default Computer Science Division environment. There are several
explicit environments available: bsd4.3, bsd4.4, hpux, irix, osf1,
riscos4.5, sunos3.5, sunos4.1, and ultrix4.1. These change things
like the location of the alias file and queue directory. Some of
these files are identical to one another.
Operating system definitions are easy to write. They may define
the following variables (everything defaults, so an ostype file
may be empty).
ALIAS_FILE [/etc/aliases] The location of the text version
of the alias file(s). It can be a comma-separated
list of names.
HELP_FILE [/usr/lib/sendmail.hf] The name of the file
containing information printed in response to
the SMTP HELP command.
QUEUE_DIR [/var/spool/mqueue] The directory containing
queue files.
STATUS_FILE [/etc/sendmail.st] The file containing status
information.
LOCAL_MAILER_PATH [/bin/mail] The program used to deliver local mail.
LOCAL_MAILER_FLAGS [rmn] The flags used by the local mailer. The
flags lsDFM are always included.
LOCAL_MAILER_ARGS [mail -d $u] The arguments passed to deliver local
mail.
LOCAL_SHELL_PATH [/bin/sh] The shell used to deliver piped email.
LOCAL_SHELL_FLAGS [eu] The flags used by the shell mailer. The
flags lsDFM are always included.
LOCAL_SHELL_ARGS [sh -c $u] The arguments passed to deliver "prog"
mail.
USENET_MAILER_PATH [/usr/lib/news/inews] The name of the program
used to submit news.
USENET_MAILER_FLAGS [rlsDFMmn] The mailer flags for the usenet mailer.
USENET_MAILER_ARGS [-m -h -n] The command line arguments for the
usenet mailer.
USENET_MAILER_MAX [100000] The maximum size of messages that will
be accepted by the usenet mailer.
SMTP_MAILER_FLAGS [undefined] Flags added to SMTP mailer. Default
flags are `mDFMUX' (and `a' for esmtp mailer).
SMTP_MAILER_MAX [undefined] The maximum size of messages that will
be transported using the smtp or esmtp mailers.
UUCP_MAILER_FLAGS [undefined] Flags added to UUCP mailer. Default
flags are `DFMhuU' (and `m' for suucp mailer, minus
`U' for uucp-dom mailer).
UUCP_MAILER_ARGS [uux - -r -z -a$f -gC $h!rmail ($u)] The arguments
passed to the UUCP mailer.
UUCP_MAX_SIZE [100000] The maximum size message accepted for
transmission by the UUCP mailers.
FAX_MAILER_PATH [/usr/local/lib/fax/mailfax] The program used to
submit FAX messages.
FAX_MAILER_MAX [100000] The maximum size message accepted for
transmission by FAX.
+---------+
| DOMAINS |
+---------+
You will probably want to collect domain-dependent defines into one
file, referenced by the DOMAIN macro. For example, our Berkeley
domain file includes definitions for several internal distinguished
hosts:
UUCP_RELAY The host that will forward UUCP-addressed email.
If not defined, all UUCP sites must be directly
connected.
BITNET_RELAY The host that will forward BITNET-addressed email.
If not defined, the .BITNET pseudo-domain won't work.
LOCAL_RELAY The site that will handle unqualified names -- that
is, names with out an @domain extension. If not set,
they are assumed to belong on this machine. This
allows you to have a central site to store a
company- or department-wide alias database. This
only works at small sites, and there are better
methods.
Each of these can be either ``mailer:hostname'' (in which case the
mailer is the internal mailer name, such as ``suucp'' and the hostname
is the name of the host as appropriate for that mailer) or just a
``hostname'', in which case a default mailer type (usually ``relay'',
a variant on SMTP) is used. WARNING: if you have a wildcard MX
record matching your domain, you probably want to define these to
have a trailing dot so that you won't get the mail diverted back
to yourself.
The domain file can also be used to define a domain name, if needed
(using "DD<domain>") and set certain site-wide features. If all hosts
at your site masquerade behind one email name, you could also use
MASQUERADE_AS here.
You do not have to define a domain -- in particular, if you are a
single machine sitting off somewhere, it is probably more work than
it's worth. This is just a mechanism for combining "domain dependent
knowledge" into one place.
+---------+
| MAILERS |
+---------+
There are fewer mailers supported in this version than the previous
version, owing mostly to a simpler world.
local The local and prog mailers. You will almost always
need these; the only exception is if you relay ALL
your mail to another site. This mailer is included
automatically.
smtp The Simple Mail Transport Protocol mailer. This does
not hide hosts behind a gateway or another other
such hack; it assumes a world where everyone is
running the name server. This file actually defines
three mailers: "smtp" for regular (old-style) SMTP to
other servers, "esmtp" for extended SMTP to other
servers, and "relay" for transmission to our
RELAY_HOST or MAILER_HUB.
uucp The Unix-to-Unix Copy Program mailer. Actually, this
defines two mailers, "uucp" and "suucp". The latter
is for when you know that the UUCP mailer at the other
end can handle multiple recipients in one transfer.
When you invoke this, sendmail looks for all names in
the $=U class and sends them to the uucp-old mailer; all
names in the $=Y class are sent to uucp-new; and all
names in the $=Z class are sent to uucp-uudom. Note that
this is a function of what version of rmail runs on
the receiving end, and hence may be out of your control.
If smtp is defined, it also defines "uucp-dom" and
"uucp-uudom" mailers that use domain-style rewriting.
See the section below describing UUCP mailers in more
detail.
usenet Usenet (network news) delivery. If this is specified,
an extra rule is added to ruleset 0 that forwards all
local email for users named ``group.usenet'' to the
``inews'' program. Note that this works for all groups,
and may be considered a security problem.
fax Facsimile transmission. This is experimental and based
on Sam Leffler's FlexFAX software. For more information,
see below.
pop Post Office Protocol.
+----------+
| FEATURES |
+----------+
Special features can be requested using the "FEATURE" macro. For
example, the .mc line:
FEATURE(use_cw_file)
tells sendmail that you want to have it read an /etc/sendmail.cw
file to get values for class $=w. The FEATURE may contain a single
optional parameter -- for example:
FEATURE(mailertable, dbm /usr/lib/mailertable)
Available features are:
use_cw_file Read the file /etc/sendmail.cw file to get alternate
names for this host. This might be used if you were
on a host that MXed for a dynamic set of other
hosts. If the set is static, just including the line
"Cw<name1> <name2> ..." is probably superior.
The actual filename can be overridden by redefining
confCW_FILE.
redirect Reject all mail addressed to "address.REDIRECT" with
a ``551 User not local; please try <address>'' message.
If this is set, you can alias people who have left
to their new address with ".REDIRECT" appended.
nouucp Don't do anything special with UUCP addresses at all.
nocanonify Don't pass addresses to $[ ... $] for canonification.
This would generally only be used by sites that only
act as mail gateways or which have user agents that do
full canonification themselves. You may also want to
use "define(`confBIND_OPTS',`-DNSRCH -DEFNAMES')" to
turn off the usual resolver options that do a similar
thing.
notsticky By default, email sent to "user@local.host" are marked
as "sticky" -- that is, the local addresses aren't
matched against UDB and don't go through ruleset 5.
This features disables this treatment. It would
normally be used on network gateway machines.
mailertable Include a "mailer table" which can be used to override
routing for particular domains. The argument of the
FEATURE may be the key definition. If none is specified,
the definition used is:
hash -o /etc/mailertable
Keys in this database are fully qualified domain names
or partial domains preceded by a dot -- for example,
"vangogh.CS.Berkeley.EDU" or ".CS.Berkeley.EDU".
Values must be of the form:
mailer:domain
where "mailer" is the internal mailer name, and "domain"
is where to send the message. These maps are not
reflected into the message header.
domaintable Include a "domain table" which can be used to provide
full domains on unqualified (single word) hosts. The
argument of the FEATURE may be the key definition. If
none is specified, the definition used is:
hash -o /etc/domaintable
The key in this table is the unqualified host name; the
value is the fully qualified domain. Anything in the
domaintable is reflected into headers; that is, this
is done in ruleset 3.
bitdomain Look up bitnet hosts in a table to try to turn them into
internet addresses. The table can be built using the
bitdomain program contributed by John Gardiner Myers.
The argument of the FEATURE may be the key definition; if
none is specified, the definition used is:
hash -o /etc/bitdomain.db
Keys are the bitnet hostname; values are the corresponding
internet hostname.
uucpdomain Similar feature for UUCP hosts. The default map definition
is:
hash -o /etc/uudomain.db
At the moment there is no automagic tool to build this
database.
always_add_domain
Include the local host domain even on locally delivered
mail. Normally it is not added unless it is already
present.
allmasquerade If masquerading is enabled (using MASQUERADE_AS), this
feature will cause recipient addresses to also masquerade
as being from the masquerade host. Normally they get
the local hostname. Although this may be right for
ordinary users, it can break local aliases. For example,
if you send to "localalias", the originating sendmail will
find that alias and send to all members, but send the
message with "To: localalias@masqueradehost". Since that
alias likely does not exist, replies will fail. Use this
feature ONLY if you can guarantee that the ENTIRE
namespace on your masquerade host supersets all the
local entries.
nodns We aren't running DNS at our site (for example,
we are UUCP-only connected). It's hard to consider
this a "feature", but hey, it had to go somewhere.
nullclient This is a special case -- it creates a stripped down
configuration file containing nothing but support for
forwarding all mail to a central hub via a local
SMTP-based network. The argument is the name of that
hub.
The only other feature that should be used in conjunction
with this one is "nocanonify" (this causes addresses to
be sent unqualified via the SMTP connection; normally
they are qualifed with the masquerade name, which
defaults to the name of the hub machine). No mailers
should be defined. No aliasing or forwarding is done.
+-------+
| HACKS |
+-------+
Some things just can't be called features. To make this clear,
they go in the hack subdirectory and are referenced using the HACK
macro. These will tend to be site-dependent. The release
includes the Berkeley-dependent "cssubdomain" hack (that makes
sendmail accept local names in either Berkeley.EDU or CS.Berkeley.EDU;
this is intended as a short-term aid while we move hosts into
subdomains.
+--------------------+
| SITE CONFIGURATION |
+--------------------+
Complex sites will need more local configuration information, such as
lists of UUCP hosts they speak with directly. This can get a bit more
tricky. For an example of a "complex" site, see cf/ucbvax.mc.
If your host is known by several different names, you need to augment
the $=w class. This is a list of names by which you are known, and
anything sent to an address using a host name in this list will be
treated as local mail. You can do this in two ways: either create
the file /etc/sendmail.cw containing a list of your aliases (one per
line), and use ``FEATURE(use_cw_file)'' in the .mc file, or add the
line:
Cw alias.host.name
at the end of that file. See the ``vangogh.mc'' file for an example.
Be sure you use the fully-qualified name of the host, rather than a
short name.
The SITECONFIG macro allows you to indirectly reference site-dependent
configuration information stored in the siteconfig subdirectory. For
example, the line
SITECONFIG(uucp.ucbvax, ucbvax, U)
reads the file uucp.ucbvax for local connection information. The
second parameter is the local name (in this case just "ucbvax" since
it is locally connected, and hence a UUCP hostname). The third
parameter is the name of both a macro to store the local name (in
this case, $U) and the name of the class (e.g., $=U) in which to store
the host information read from the file. Another SITECONFIG line reads
SITECONFIG(uucp.ucbarpa, ucbarpa.Berkeley.EDU, W)
This says that the file uucp.ucbarpa contains the list of UUCP sites
connected to ucbarpa.Berkeley.EDU. The $=W class will be used to
store this list, and $W is defined to be ucbarpa.Berkeley.EDU, that
is, the name of the relay to which the hosts listed in uucp.ucbarpa
are connected. [The machine ucbarpa is gone now, but I've left
this out-of-date configuration file around to demonstrate how you
might do this.]
Note that the case of SITECONFIG with a third parameter of ``U'' is
special; the second parameter is assumed to be the UUCP name of the
local site, rather than the name of a remote site, and the UUCP name
is entered into $=w (the list of local hostnames) as $U.UUCP.
The siteconfig file (e.g., siteconfig/uucp.ucbvax.m4) contains nothing
more than a sequence of SITE macros describing connectivity. For
example:
SITE(cnmat)
SITE(sgi olympus)
The second example demonstrates that you can use two names on the
same line; these are usually aliases for the same host (or are at
least in the same company).
+--------------------+
| USING UUCP MAILERS |
+--------------------+
It's hard to get UUCP mailers right because of the extremely ad hoc
nature of UUCP addressing. These config files are really designed
for domain-based addressing, even for UUCP sites.
There are four UUCP mailers available. The choice of which one to
use is partly a matter of local preferences and what is running at
the other end of your UUCP connection. Unlike good protocols that
define what will go over the wire, UUCP uses the policy that you
should do what is right for the other end; if they change, you have
to change. This makes it hard to do the right thing, and discourages
people from updating their software. In general, if you can avoid
UUCP, please do.
The major choice is whether to go for a domainized scheme or a
non-domainized scheme. This depends entirely on what the other
end will recognize. If at all possible, you should encourage the
other end to go to a domain-based system -- non-domainized addresses
don't work entirely properly.
The four mailers are:
uucp-old (obsolete name: "uucp")
This is the oldest, the worst (but the closest to UUCP) way of
sending messages accros UUCP connections. It does bangify
everything and prepends $U (your UUCP name) to the sender's
address (which can already be a bang path itself). It can
only send to one address at a time, so it spends a lot of
time copying duplicates of messages. Avoid this if at all
possible.
uucp-new (obsolete name: "suucp")
The same as above, except that it assumes that in one rmail
command you can specify several recipients. It still has a
lot of other problems.
uucp-dom
This UUCP mailer keeps everything as domain addresses.
Basically, it uses the SMTP mailer rewriting rules.
Unfortunately, a lot of UUCP mailer transport agents require
bangified addresses in the envelope, although you can use
domain-based addresses in the message header. (The envelope
shows up as the From_ line on UNIX mail.) So....
uucp-uudom
This is a cross between uucp-new (for the envelope addresses)
and uucp-dom (for the header addresses). It bangifies the
envelope sender (From_ line in messages) without adding the
local hostname, unless there is no host name on the address
at all (e.g., "wolf") or the host component is a UUCP host name
instead of a domain name ("somehost!wolf" instead of
"some.dom.ain!wolf").
Examples:
We are on host grasp.insa-lyon.fr (UUCP host name "grasp"). The
following summarizes the sender rewriting for various mailers.
Mailer sender rewriting in the envelope
------ ------ -------------------------
uucp-{old,new} wolf grasp!wolf
uucp-dom wolf wolf@grasp.insa-lyon.fr
uucp-uudom wolf grasp.insa-lyon.fr!wolf
uucp-{old,new} wolf@fr.net grasp!fr.net!wolf
uucp-dom wolf@fr.net wolf@fr.net
uucp-uudom wolf@fr.net fr.net!wolf
uucp-{old,new} somehost!wolf grasp!somehost!wolf
uucp-dom somehost!wolf somehost!wolf@grasp.insa-lyon.fr
uucp-uudom somehost!wolf grasp.insa-lyon.fr!somehost!wolf
If you are using one of the domainized UUCP mailers, you really want
to convert all UUCP addresses to domain format -- otherwise, it will
do it for you (and probably not the way you expected). For example,
if you have the address foo!bar!baz (and you are not sending to foo),
the heuristics will add the @uucp.relay.name or @local.host.name to
this address. However, if you map foo to foo.host.name first, it
will not add the local hostname. You can do this using the uucpdomain
feature.
+-------------------+
| TWEAKING RULESETS |
+-------------------+
For more complex configurations, you can define special rules.
The macro LOCAL_RULE_3 introduces rules that are used in canonicalizing
the names. Any modifications made here are reflected in the header.
A common use is to convert old UUCP addreses to SMTP addresses using
the UUCPSMTP macro. For example:
LOCAL_RULE_3
UUCPSMTP(decvax, decvax.dec.com)
UUCPSMTP(research, research.att.com)
will cause addresses of the form "decvax!user" and "research!user"
to be converted to "user@decvax.dec.com" and "user@research.att.com"
respectively.
This could also be used to look up hosts in a database map:
LOCAL_RULE_3
R$* < @ $+ > $* $: $1 < @ $(hostmap $2 $) > $3
This map would be defined in the LOCAL_CONFIG portion, as shown below.
Similarly, LOCAL_RULE_0 can be used to introduce new parsing rules.
For example, new rules are needed to parse hostnames that you accept
via MX records. For example, you might have:
LOCAL_RULE_0
R$+ <@ host.dom.ain.> $#uucp $@ cnmat $: $1 < @ host.dom.ain.>
You would use this if you had installed an MX record for cnmat.Berkeley.EDU
pointing at this host; this rule catches the message and forwards it on
using UUCP.
You can also tweak rulesets 1 and 2 using LOCAL_RULE_1 and LOCAL_RULE_2.
These rulesets are normally empty.
A similar macro is LOCAL_CONFIG. This introduces lines added after the
boilerplate option setting but before rulesets, and can be used to
declare local database maps or whatever. For example:
LOCAL_CONFIG
Khostmap hash /etc/hostmap.db
Kyplocal nis -m hosts.byname
+---------------------------+
| MASQUERADING AND RELAYING |
+---------------------------+
You can have your host masquerade as another using
MASQUERADE_AS(host.domain)
This causes outgoing SMTP mail to be labeled as coming from the
indicated domain, rather than $j. One normally masquerades as one
of one's own subdomains (for example, it's unlikely that I would
choose to masquerade as an MIT site).
The masquerade name is not normally canonified, so it is important
that it be your One True Name, that is, fully qualified and not a
CNAME.
there are always users that need to be "exposed" -- that is, their
internal site name should be displayed instead of the masquerade name.
Root is an example. You can add users to this list using
EXPOSED_USER(usernames)
This adds users to class E; you could also use something like
FE/etc/sendmail.cE
You can also arrange to relay all unqualified names (that is, names
without @host) to a relay host. For example, if you have a central
email server, you might relay to that host so that users don't have
to have .forward files or aliases. You can do this using
define(`LOCAL_RELAY', mailer:hostname)
The ``mailer:'' can be omitted, in which case the mailer defaults to
"smtp". There are some user names that you don't want relayed, perhaps
because of local aliases. A common example is root, which may be
locally aliased. You can add entries to this list using
LOCAL_USER(usernames)
This adds users to class L; you could also use something like
FL/etc/sendmail.cL
If you want all incoming mail sent to a centralized hub, as for a
shared /var/spool/mail scheme, use
define(`MAIL_HUB', mailer:hostname)
Again, ``mailer:'' defaults to "smtp". If you define both LOCAL_RELAY
and MAIL_HUB, unqualified names will be sent to the LOCAL_RELAY and
other local names will be sent to MAIL_HUB. Names in $=L will be
delivered locally, so you MUST have aliases or .forward files for them.
For example, if are on machine mastodon.CS.Berkeley.EDU, the following
combinations of settings will have the indicated effects:
email sent to.... eric eric@mastodon.CS.Berkeley.EDU
LOCAL_RELAY set to mail.CS.Berkeley.EDU (delivered locally)
mail.CS.Berkeley.EDU
MAIL_HUB set to mammoth.CS.Berkeley.EDU mammoth.CS.Berkeley.EDU
mammoth.CS.Berkeley.EDU
Both LOCAL_RELAY and mail.CS.Berkeley.EDU mammoth.CS.Berkeley.EDU
MAIL_HUB set as above
If you want all outgoing mail to go to a central relay site, define
SMART_HOST as well. Briefly:
LOCAL_RELAY applies to unqualifed names (e.g., "eric").
MAIL_HUB applies to names qualified with the name of the
local host (e.g., "eric@mastodon.CS.Berkeley.EDU").
SMART_HOST applies to names qualified with other hosts.
However, beware that other relays (e.g., UUCP_RELAY, BITNET_RELAY, and
FAX_RELAY) take precedence over SMART_HOST, so if you really want
absolutely everything to go to a single central site you will need to
unset all the other relays -- or better yet, find or build a minimal
config file that does this.
+-------------------------------+
| NON-SMTP BASED CONFIGURATIONS |
+-------------------------------+
These configuration files are designed primarily for use by SMTP-based
sites. I don't pretend that they are well tuned for UUCP-only or
UUCP-primarily nodes (the latter is defined as a small local net
connected to the rest of the world via UUCP). However, there is one
hook to handle some special cases.
You can define a ``smart host'' that understands a richer address syntax
using:
define(`SMART_HOST', mailer:hostname)
In this case, the ``mailer:'' defaults to "relay". Any messages that
can't be handled using the usual UUCP rules are passed to this host.
If you are on a local SMTP-based net that connects to the outside
world via UUCP, you can use LOCAL_NET_CONFIG to add appropriate rules.
For example:
define(`SMART_HOST', suucp:uunet)
LOCAL_NET_CONFIG
R$* < @ $* .$m. > $* $#smtp $@ $2.$m. $: $1 < @ $2.$m. > $3
This will cause all names that end in your domain name ($m) via
SMTP; anything else will be sent via suucp (smart UUCP) to uunet.
If you have FEATURE(nocanonify), you may need to omit the dots after
the $m. If you are running a local DNS inside your domain which is
not otherwise connected to the outside world, you probably want to
use:
define(`SMART_HOST', smtp:fire.wall.com)
LOCAL_NET_CONFIG
R$* < @ $* . > $* $#smtp $@ $2. $: $1 < @ $2. > $3
That is, send directly only to things you found in your DNS lookup;
anything else goes through SMART_HOST.
If you are not running DNS at all, it is important to use
FEATURE(nodns) to avoid having sendmail queue everything waiting
for the name server to come up.
+-----------+
| WHO AM I? |
+-----------+
Normally, the $j macro is automatically defined to be your fully
qualified domain name (FQDN). Sendmail does this by getting your
host name using gethostname and then calling gethostbyname on the
result. For example, in some environments gethostname returns
only the root of the host name (such as "foo"); gethostbyname is
supposed to return the FQDN ("foo.bar.com"). In some (fairly rare)
cases, gethostbyname may fail to return the FQDN. In this case
you MUST define confDOMAIN_NAME to be your fully qualified domain
name. This is usually done using:
Dmbar.com
define(`confDOMAIN_NAME', `$w.$m')dnl
+--------------------+
| USING MAILERTABLES |
+--------------------+
To use FEATURE(mailertable), you will have to create an external
database containing the routing information for various domains.
For example, a mailertable file in text format might be:
.my.domain xnet:%1.my.domain
uuhost1.my.domain suucp:uuhost1
.bitnet smtp:relay.bit.net
This should normally be stored in /etc/mailertable. The actual
database version of the mailertable is built using:
makemap hash /etc/mailertable.db < /etc/mailertable
The semantics are simple. Any LHS entry that does not begin with
a dot matches the full host name indicated. LHS entries beginning
with a dot match anything ending with that domain name -- that is,
they can be thought of as having a leading "*" wildcard. Matching
is done in order of most-to-least qualified -- for example, even
though ".my.domain" is listed first in the above example, an entry
of "uuhost1.my.domain" will match the second entry since it is
more explicit.
The RHS should always be a "mailer:host" pair. The mailer is the
configuration name of a mailer (that is, an `M' line in the
sendmail.cf file). The "host" will be the hostname passed to
that mailer. In domain-based matches (that is, those with leading
dots) the "%1" may be used to interpolate the wildcarded part of
the host name. For example, the first line above sends everything
addressed to "anything.my.domain" to that same host name, but using
the (presumably experimental) xnet mailer.
+--------------------------------+
| USING USERDB TO MAP FULL NAMES |
+--------------------------------+
The user database was not originally intended for mapping full names
to login names (e.g., Eric.Allman => eric), but some people are using
it that way. (I would recommend that you set up aliases for this
purpose instead -- since you can specify multiple alias files, this
is fairly easy.) The intent was to locate the default maildrop at
a site, but allow you to override this by sending to a specific host.
If you decide to set up the user database in this fashion, it is
imperative that you also specify FEATURE(notsticky) -- otherwise,
e-mail sent to Full.Name@local.host.name will be rejected.
To build the internal form of the user databae, use:
makemap btree /usr/data/base.db < /usr/data/base.txt
+------------------+
| FlexFAX SOFTWARE |
+------------------+
Sam Leffler's FlexFAX software is still in beta test -- but he expects a
public version out "later this week" [as of 3/1/93]. The following
blurb is direct from Sam:
$Header: /cvsroot/src/usr.sbin/sendmail/cf/Attic/README,v 1.8 1994/03/16 02:11:48 glass Exp $
How To Obtain This Software (in case all you get is this file)
--------------------------------------------------------------
The source code is available for public ftp on
sgi.com sgi/fax/v2.1.src.tar.Z
(192.48.153.1)
You can also obtain inst'able images for Silicon Graphics machines from
sgi.com sgi/fax/v2.1.inst.tar
(192.48.153.1)
For example,
% ftp -n sgi.com
....
ftp> user anonymous
... <type in password>
ftp> cd sgi/fax
ftp> binary
ftp> get v2.1.src.tar.Z
In general, the latest version of the 2.1 release of the software is
always available as "v2.1.src.tar.Z" or "v2.1.inst.tar" in the ftp
directory. This file is a link to the appropriate released version (so
don't waste your time retrieving the linked file as well!) Any files of
the form v2.1.*.patch are shell scripts that can be used to patch older
versions of the source code. For example, the file v2.1.0.patch would
contain patches to update v2.1.0.tar.Z. (Note to beta testers: this is
different than the naming conventions used during beta testing.) Patch
files only work to go between consecutive versions, so if you are
multiple versions behind the latest release, you will need to apply
each patch file between your current version and the latest.
Obtaining the Software by Electronic Mail
-----------------------------------------
Do not send me requests for the software; they will be ignored (without
response). If you cannot use FTP at all, there is a service called
"ftpmail" available from gatekeeper.dec.com: you can send e-mail to
this machine and it will use FTP to retrieve files for you and send you
the files back again via e-mail. To find out more about the ftpmail
service, send a message to "ftpmail@gatekeeper.dec.com" whose body
consists of the single line "help".
Obtaining the Software Within Silicon Graphics
----------------------------------------------
Internal to Silicon Graphics there are inst'able images on the host
flake.asd in the directory /usr/dist. Thus you can do something like:
% inst -f flake.asd.sgi.com:/usr/dist/flexfax
to install the latest version of the software on your machine.
What to do Once You've Retrieved Stuff
--------------------------------------
The external distributions come in a compressed or uncompressed tar
file. To extract the source distribution:
% zcat v2.1.src.tar.Z | tar xf -
(uncompress and extract individual files in current directory). To
unpack and install the client portion of the inst'able distribution:
% mkdir dist
% cd dist; tar xf ../v2.1.inst.tar; cd ..
% inst -f dist/flexfax
...
inst> go
(Note, the dist subdirectory is because some versions of inst fail if
the files are in the current directory.) Server binaries are also
included in the inst'able images as flexfax.server.*. They are not
installed by default, so to get them also you need to do:
% inst -f flexfax
...
inst> install flexfax.server.*
inst> go
The SGI binaries were built for Version 4.0.5H of the IRIX operating
system. They should work w/o problem on earlier versions of the
system, but I have not fully tested this. Also, note that to install a
server on an SGI machine, you need to have installed the Display
PostScript execution environment product (dps_eoe). Otherwise, the fax
server will not be able to convert PostScript to facsimile for
transmission.
If you are working from the source distribution, look at the file
README in the top of the source tree. If you are working from the inst
images, the subsystem flexfax.man.readme contains the README file and
other useful pieces of information--the installed files are placed in
the directory /usr/local/doc/flexfax). Basically you will need to run
the faxaddmodem script to setup and configure your fax modem. Consult
the README file and the manual page for faxaddmodem for information.
FlexFAX Mail List
-----------------
A mailing list for users of this software is located on sgi.com.
If you want to join this mailing list or have a list-related request
such as getting your name removed from it, send a request to
majordomo@whizzer.wpd.sgi.com
For example, to subscribe, send the line "subscribe flexfax" in
the body of your message. The line "help" will return a list of
the commands understood by the mailing list management software.
Submissions (including bug reports) should be directed to:
flexfax@sgi.com
When corresponding about this software please always specify what
version you have, what system you're running on, and, if the problem is
specific to your modem, identify the modem and firmware revision.
+--------------------------------+
| TWEAKING CONFIGURATION OPTIONS |
+--------------------------------+
There are a large number of configuration options that don't normally
need to be changed. However, if you feel you need to tweak them, you
can define the following M4 variables. This list is shown in four
columns: the name you define, the default value for that definition,
the option or macro that is affected (either Ox for an option or Dx
for a macro), and a brief description. Greater detail of the semantics
can be found in the Installation and Operations Guide.
Some options are likely to be deprecated in future versions -- that is,
the option is only included to provide back-compatibility. These are
marked with "*".
Remember that these options are M4 variables, and hence may need to
be quoted. In particular, arguments with commas will usually have to
be ``double quoted, like this phrase'' to avoid having the comma
confuse things. This is common for alias file definitions and for
the read timeout.
M4 Variable Name Default Mac/Opt Description
================ ======= ======= ===========
confMAILER_NAME MAILER-DAEMON Dn The sender name used for
internally generated
outgoing messages.
confFROM_LINE From $g $d Dl The From_ line used when
sending to files or programs.
confFROM_HEADER $?x$x <$g>$|$g$. The format of an internally
Dq generated From: address.
confOPERATORS .:%@!^/[] Do Address operator characters.
confSMTP_LOGIN_MSG $j Sendmail $v/$Z ready at $b
De The initial (spontaneous)
SMTP greeting message.
confSEVEN_BIT_INPUT False O7 Force input to seven bits?
confALIAS_WAIT 10 Oa Wait (in minutes) for alias
file rebuild.
confMIN_FREE_BLOCKS 4 Ob Minimum number of free blocks
on queue filesystem to accept
SMTP mail.
confBLANK_SUB . OB Blank (space) substitution
character.
confCON_EXPENSIVE False Oc Avoid connecting immediately
to mailers marked expensive?
confCHECKPOINT_INTERVAL 10 OC Checkpoint queue files
every N recipients.
confDELIVERY_MODE background Od Default delivery mode.
confAUTO_REBUILD False OD Automatically rebuild
alias file if needed.
confERROR_MODE (undefined) Oe Error message mode.
confERROR_MESSAGE (undefined) OE Error message header/file.
confSAVE_FROM_LINES False Of Save extra leading
From_ lines.
confTEMP_FILE_MODE 0600 OF Temporary file mode.
confDEF_GROUP_ID 1 Og Default group id.
confMATCH_GECOS False OG Match GECOS field.
confMAX_HOP 17 Oh Maximum hop count.
confIGNORE_DOTS False Oi * Ignore dot as terminator
for incoming messages?
confBIND_OPTS (empty) OI Default options for BIND.
confMIME_FORMAT_ERRORS True Oj * Send error messages as MIME-
encapsulated messages per
RFC 1344.
confFORWARD_PATH (undefined) OJ The colon-separated list of
places to search for .forward
files.
confMCI_CACHE_SIZE 2 Ok Size of open connection cache.
confMCI_CACHE_TIMEOUT 5m OK Open connection cache timeout.
confUSE_ERRORS_TO False Ol * Use the Errors-To: header to
deliver error messages. This
should not be necessary because
of general acceptance of the
envelope/header distinction.
confLOG_LEVEL 9 OL Log level.
confME_TOO False Om Include sender in group
expansions.
confCHECK_ALIASES True On Check RHS of aliases when
running newaliases.
confOLD_STYLE_HEADERS True Oo * Assume that headers without
special chars are old style.
confDAEMON_OPTIONS (undefined) OO SMTP daemon options.
confPRIVACY_FLAGS authwarnings Op Privacy flags.
confCOPY_ERRORS_TO (undefined) OP Address for additional copies
of all error messages.
confQUEUE_FACTOR (undefined) Oq Slope of queue-only function
confREAD_TIMEOUT (undefined) Or SMTP read timeouts.
confSAFE_QUEUE True Os * Commit all messages to disk
before forking.
confMESSAGE_TIMEOUT 5d/4h OT Timeout for messages before
sending error/warning message.
confTIME_ZONE USE_SYSTEM Ot Time zone info -- can be
USE_SYSTEM to use the system's
idea, USE_TZ to use the user's
TZ envariable, or something
else to force that value.
confDEF_USER_ID 1 Ou Default user id.
confUSERDB_SPEC (undefined) OU User database specification.
confFALLBACK_MX (undefined) OV Fallback MX host.
confTRY_NULL_MX_LIST False Ow If we are the best MX for a
host and haven't made other
arrangements, try connecting
to the host directly; normally
this would be a config error.
confQUEUE_LA 8 Ox Load average at which queue-only
function kicks in.
confREFUSE_LA 12 OX Load average at which incoming
SMTP connections are refused.
confWORK_RECIPIENT_FACTOR
(undefined) Oy Cost of each recipient.
confSEPARATE_PROC False OY Run all deliveries in a
separate process.
confWORK_CLASS_FACTOR (undefined) Oz Priority multiplier for class.
confWORK_TIME_FACTOR (undefined) OZ Cost of each delivery attempt.
confCW_FILE /etc/sendmail.cw Name of file used to get the
Fw local additions to the $=w
class.
confSMTP_MAILER smtp - The mailer name used when
SMTP connectivity is required.
Either "smtp" or "esmtp".
confLOCAL_MAILER local - The mailer name used when
local connectivity is required.
Almost always "local".
confRELAY_MAILER relay - The default mailer name used
for relaying any mail (e.g.,
to a BITNET_RELAY, a
SMART_HOST, or whatever).
This can reasonably be "suucp"
if you are on a UUCP-connected
site.
confDOMAIN_NAME (undefined) Dj If defined, sets $j.
+-----------+
| HIERARCHY |
+-----------+
Within this directory are several subdirectories, to wit:
m4 General support routines. These are typically
very important and should not be changed without
very careful consideration.
cf The configuration files themselves. They have
".mc" suffixes, and must be run through m4 to
become complete. The resulting output should
have a ".cf" suffix.
ostype Definitions describing a particular operating
system type. These should always be referenced
using the OSTYPE macro in the .mc file. Examples
include "bsd4.3", "bsd4.4", "sunos3.5", and
"sunos4.1".
domain Definitions describing a particular domain, referenced
using the DOMAIN macro in the .mc file. These are
site dependent; for example, we contribute "cs.exposed.m4"
and "cs.hidden.m4" which both describe hosts in the
CS.Berkeley.EDU subdomain; the former displays the local
hostname (e.g., mammoth.CS.Berkeley.EDU), whereas the
latter does its best to hide the identity of the local
workstation inside the CS subdomain.
mailer Descriptions of mailers. These are referenced using
the MAILER macro in the .mc file.
sh Shell files used when building the .cf file from the
.mc file in the cf subdirectory.
feature These hold special orthogonal features that you might
want to include. They should be referenced using
the FEATURE macro.
hack Local hacks. These can be referenced using the HACK
macro. They shouldn't be of more than voyeuristic
interest outside the .Berkeley.EDU domain, but who knows?
We've all got our own peccadillos.
siteconfig Site configuration -- e.g., tables of locally connected
UUCP sites.
+------------------------+
| ADMINISTRATIVE DETAILS |
+------------------------+
The following sections detail usage of certain internal parts of the
sendmail.cf file. Read them carefully if you are trying to modify
the current model. If you find the above descriptions adequate, these
should be {boring, confusing, tedious, ridiculous} (pick one or more).
RULESETS (* means built in to sendmail)
0 * Parsing
1 * Sender rewriting
2 * Recipient rewriting
3 * Canonicalization
4 * Post cleanup
5 * Local address rewrite (after aliasing)
1x mailer rules (sender qualification)
2x mailer rules (recipient qualification)
3x mailer rules (sender header qualification)
4x mailer rules (recipient header qualification)
5x mailer subroutines (general)
6x mailer subroutines (general)
7x mailer subroutines (general)
8x reserved
90 Mailertable host stripping
96 Bottom half of Ruleset 3 (ruleset 6 in old sendmail)
97 Hook for recursive ruleset 0 call (ruleset 7 in old sendmail)
98 Local part of ruleset 0 (ruleset 8 in old sendmail)
MAILERS
0 local, prog local and program mailers
1 [e]smtp, relay SMTP channel
2 uucp-* UNIX-to-UNIX Copy Program
3 netnews Network News delivery
4 fax Sam Leffler's FlexFAX software
MACROS
A
B Bitnet Relay
C
D The local domain -- usually not needed
E
F FAX Relay
G
H mail Hub (for mail clusters)
I
J
K
L
M Masquerade (who I claim to be)
N
O
P
Q
R Relay (for unqualified names)
S Smart Host
T
U my UUCP name (if I have a UUCP connection)
V UUCP Relay (class V hosts)
W UUCP Relay (class W hosts)
X UUCP Relay (class X hosts)
Y UUCP Relay (all other hosts)
Z Version number
CLASSES
A
B
C
D
E addresses that should not seem to come from $M
F hosts we forward for
G
H
I
J
K
L addresses that should not be forwarded to $R
M
N
O operators that indicate network operations (cannot be in local names)
P top level pseudo-domains: BITNET, FAX, UUCP, etc.
Q
R
S
T
U locally connected UUCP hosts
V UUCP hosts connected to relay $V
W UUCP hosts connected to relay $W
X UUCP hosts connected to relay $X
Y locally connected smart UUCP hosts
Z locally connected domain-ized UUCP hosts
. the class containing only a dot
M4 DIVERSIONS
1 Local host detection and resolution
2 Local Ruleset 3 additions
3 Local Ruleset 0 additions
4 UUCP Ruleset 0 additions
5 locally interpreted names (overrides $R)
6 local configuration (at top of file)
7 mailer definitions
8
9 special local rulesets (1 and 2)
