SMAILDRCT(5) Local SMAILDRCT(5)NAME
/etc/smail/directors - smail configuration of local address handling
THE DIRECTORS FILE
The directors file describes the operations, and their order, for han‐
dling local addresses. For example, some possibilities are to expand a
local address into a list of local and remote addresses through an
alias file, forward file or mailing list, or to cause mail to be deliv‐
ered to a local user.
The following list describes the possible generic attributes for direc‐
tors file entries:
caution
type: boolean
If set then be cautious of addresses produced by this director. If
the nobody attribute is not set, then reject file, shell command or
:include:filename-style mailing list addresses.
default_group
type: string
If the driver does not associate a group to an address returned by
it, then associate the group id for this group name. This will
override the gid set by a default_user attribute.
default_home
type: string
If the driver does not associate a home directory with an address
returned by it, then use this home directory.
The value will be expanded to form the actual directory pathname.
At the present time, the $user variable is not available for this
expansion. If the string expansion fails, it is ignored.
default_user
type: string
If the driver does not associate a user or group to an address
returned by it, then associate the user-ID and group-ID of this
user.
domains
type: string
This attribute specifies a colon-separated list of domains. If it
is present, the actual local domain given in an address (or the
visible name if no domain is given) is tested against this list,
and if it does not match any entry, the director is skipped. This
makes it possible to set up differential handling of local domains.
For example, if both foo.ac.uk and lists.foo.ac.uk are defined as
local domains, the following configuration ensures that messages
sent to foo.ac.uk are handled by their own director.
# handle messages addressed to lists on the local host
lists:
driver = forwardfile,
caution,
nobody,
domains="lists.foo.ac.uk",
owner = $user-request@lists.foo.ac.uk;
file = lists/${lc:user}
# match users on the local host
user:
domains="foo.ac.uk",
driver = user;
transport = local
driver
type: string
The driver attribute names a specific set of low-level functions
which will do the work of directing local mail. This attribute is
required for all director instances.
ignore_alias_match
type: boolean
If the new address found by the director driver is the same as the
input address it will normally be sent to the next director. Eg.,
``foo'' aliased to ``foo'' will probably end up being delivered to
the local user named ``foo''. However if the ignore_alias_match
attribute is set on the director, and that director returns an
address identical to the input address, the whole thing will just
be dropped, provided the returned address was not escaped (e.g.
``\foo''), of course. This attribute is hardly ever used, and is
not used in any of the default director configurations.
nobody
type: boolean
If set, then access files, or run shell commands as the user speci‐
fied by the nobody attribute, for addresses flagged with caution by
either the caution generic attribute or by the driver.
Association of nobody with an address overrides the default_user,
default_group, set_user, and set_group attributes. This attribute
is set by default.
owner
type: string
The owner attribute names the address to be sent mail if an error
occurs in processing the addresses produced by this director
instance, i.e. the sender address to be used. This string is
expanded with the variable $user set to the local-form address
passed to the director. Commonly the value will be
``owner-$user''. If this string expansion fails, it is treated as
if it were not set. This attribute should generally be set to
``owner-$user'' in all director instances that might return non-
local addresses.
Owner addresses are verified at the time this director instance
matches an input address. If the owner address is not valid then
``postmaster'' will be used as the sender address instead.
sender_okay
type: boolean
If set, then it is always okay for this attribute to produce an
address equal to the sender. This effectively turns on the ``me
too'' flag for this director. This attribute should generally be
set true for forwarding directors and should not be set (set false)
for aliasing and mailing list directors.
set_group
type: string
Associate the group-ID of this group with the addresses returned by
the driver. This overrides any group-ID set by the set_user
attribute.
set_home
type: string
Associate this home directory with all addresses returned by the
driver. This will be expanded in the same manner as default_home.
set_user
type: string
Associate the user-ID, and group-ID (unless set_group is also
given), of this user with addresses returned by this director
instance's driver. This overrides any values set by the director
driver.
There are two addresses which are required by the mailer software to
exist: the address Postmaster (also required by by RFC 822 and RFC
2142!) and the address Mailer-Daemon. To avoid the necessity of an
alias for these two users, smail contains two implicit directors embed‐
ded into the directing code. These implicit directors are used as a
last resort. The first such director maps the address Mailer-Daemon
onto the address Postmaster and the second maps Postmaster onto the
address root.
THE DIRECTOR DRIVERS
This section details the usage and driver-specific attributes for all
of the director drivers distributed with smail.
The Aliasfile Driver
The base standard for the format of the aliases and forward files
should be the format used by the BSD sendmail program. This format is
simple yet powerful enough for most needs.
A sendmail-compatible aliases file consists of relations between alias
names and the lists of entities to that the aliases expand. Each entry
is of the form:
alias-name: address, ...
If an aliasinclude director (see the sub-section The Mailing-list Driv‐
ers below) is defined then any address may also be of the form
:include:/pathname/to/list/of/addresses
The following is a sample alias file for a machine nsavax:
# Sample aliasing file for nsavax
#
# redirect root's mail
root: brown, casey
#
# mail sent to MAILER-DAEMON should go to postmaster
MAILER-DAEMON: postmaster
#
# brown maintains netnews and mail
postmaster: brown
netnews: brown
#
# copy fawn on all north's mail
north: north, fawn
#
# post important information to network
msgs: local-msgs@ciacray, local-msgs@nscprofs, local-msgs@nsavax
local-msgs: "|/usr/ucb/msgs -s" # deliver to msgs program
#
# administrivia
rnews: "|/usr/lib/news/uurec" # read news messages from mail
#
# mailing lists for accessing users on the local network
nsavax-users: :include:/usr/lib/mail/nsavax-users
ciacray-users: :include:/usr/lib/mail/ciacray-users
nscprofs-users: :include:/usr/lib/mail/nscprofs-users
#
# mail to everybody on the local network
everybody: nsavax-users, # well, almost everybody
ciacray-users,
nscprofs-users
#
# save mail to mailing list requests and send to moderator
funding-request: /usr/log/funding-req, reagan@nscprofs
covert-bugs-request: /usr/log/covert-bugs-req, james.bond@ciacray
#
# broadcast to mailing lists, and save a copy
funding: # excludes congress
:include:/usr/list/funding,
# save all messages here
/usr/log/funding
#
covert-bugs: # includes kgb
:include:/usr/list/covert-bugs,
/usr/log/covert-bugs # save all messages here
The aliasfile driver searches for matches between a local address on
input and an alias-name from the alias file. If a match is found, it
returns the associated list.
It has the following driver attributes:
file
type: string
Define the name of the file containing the database. Except when
this is not appropriate for the proto being used, if this does not
begin with a slash (``/''), it will be referenced relative to the
smail_lib_dir directory.
interval
type: number
A sleep interval between open retries, in seconds. On systems
which have one second granularities on wakeup times and where, as a
result, sleep times can be nearly 0 seconds, this number should be
at least 2.
modemask
type: number
A mask, ala umask(2), defining the maximum permissiveness allowed
for the permissions on the alias file. For example, a modemask of
022 disallows write access to all but the file owner. This value
should be chosen to strike a reasonable compromise between security
and user convenience. It should also take into account the use of
the owners and owngroups attributes described below. A paragraph
below describes the consequences for a file not meeting this crite‐
ria.
optional
type: boolean
If set, then if the open fails, assume an empty alias file. This
is useful for optional databases. For example, in a networking
environment, workstations may be configured with the option of hav‐
ing a private alias file, without the necessity of creating such a
file on each host.
owners
type: string
A list of permissible owners for the alias file. A paragraph below
describes the consequences for a file not meeting this criteria.
owngroups
type: string
A list of permissible owning groups for the alias file. A para‐
graph below describes the consequences for a file not meeting this
criteria.
proto
type: string
Names the protocol used in opening and searching the database.
Possibilities are discussed below.
reopen
type: boolean
If this attribute is on, the alias file will be closed and reopened
after each call to the driver. This is useful for systems that
have a shortage of file descriptors yet wish to access a large num‐
ber of databases.
retries
type: number
the maximum count of open retries. This should be greater than
zero if the system does not have an atomic rename(2) system call,
as the alias file may not always exist while being modified.
tryagain
type: boolean
If set, then if the open fails, the resolution of local addresses
will be attempted at a later time. This is useful in a networking
environment where failure to open a database (such as a remote YP
database) may be a result of a server machine being down or tempo‐
rarily inaccessible.
If any of the attributes modemask, owners, or owngroups reject the file
as a possible security problem, all addresses returned are flagged with
the caution bit set. See the generic director attribute nobody for
more information.
The current list of possible values for the proto attribute is:
bsearch Use a binary search to look through a sorted file arranged as
lines which begin with a key and are followed by the value
associated with the key, separated by a colon or whitespace.
The file should be sorted by the key, not by the line. The
mksort(8) utility sorts lines correctly. Care should be
taken when using the regular sort(1) to ensure that the sort
uses proper delimiters.
dbm Use the BSD dbm(3x) or ndbm(3x) [or the db(3x) emulation of
ndbm] routines to search for the key. The keys and data in
the dbm database must end in a NUL byte. If only the dbm
library is available then only one dbm database can be used
by smail, while the ndbm routines will allow any number of
databases to be used simultaneously. Note that it is always
okay for multiple routers and directors to use the same dbm
database, if this is useful.
aliasyp This is a variant of the yp protocol that is compatible with
the standard Sun mail.aliases YP service. This database has
a different format from other databases which must be taken
into account when sending requests. Typically this is not
useful for a path database.
lsearch Use a linear search using the same read routine used to read
config files. `#'-style comments are allowed and the begin‐
ning of each file entry should be the key, followed by white‐
space or a colon character. The rest of the entry should be
the value associated with the key.
yp Use the Sun YP service to access a paths database stored on a
remote machine. In this case the value for the file
attribute is of the form:
domain_name:database_name
where the ``domain_name:'' part is optional and defaults to
the default YP domain for the local host.
nialias Use the NeXT NetInfo database, for getting user aliasing
information.
nisplus Look up the key in a remote Sun NIS+ (Sun NIS version 3)
database. NIS+ is not compatible with NIS (otherwise known
as YP). The file parameter must be a NIS+ indexed name,
which is described in the nis(1) manual page. The search
string is replaced with ``%s'' where it can be filled in by
smail's NIS+ lookup routine.
# search for alias expansions stored in a NIS+ database
nisaliases:
driver = aliasfile;
file = "[alias=%s],mail_aliases.org_dir",
proto = nisplus
The lookup routine within smail allows you to choose which
field to get from the NIS+ database by prepending the file
with a string like ``@2,''. That example would use field
number 2 from the table. The default action, as in the
nisaliases example above, is to use field 1. (Field 0 is
usually the index value.)
Though you wouldn't necessarily want to do this, the follow‐
ing example allows you to send mail to all the members of
groups in your NIS+ group list as if each were a separate
mail list.
# use NIS+ groups as mail lists
nisgroups:
driver = aliasfile;
file = "@3,[name=%s],group.org_dir",
proto = nisplus
A simple entry in the director file is:
# don't perform any authentication on the alias file
aliases: driver=aliasfile;
file=/usr/lib/aliases, proto=dbm
The Forwardfile Driver
Sendmail-compatible forward files have the same structure as mailing
lists. This format is:
address, address, ...
Where newlines can be included wherever whitespace is allowed, and
where a `#' character begins a comment that ends at the end of the
line. Comments are treated as whitespace.
If a forwardinclude director (see the sub-section The Mailing-list
Drivers below) is defined then any address may also be of the form
:include:/pathname/to/list/of/addresses
An example forward file for the user ``james.bond'' on the host
``nsavax'' is:
# send to my own machine, but keep a copy here
# just in case it doesn't make it there.
bond%british-ss@ciacray, james.bond
A useful forward file might be something like this:
"|$HOME/bin/gone-fishing myuserid"
and in your ~/bin/gone-fishing script writing something like the fol‐
lowing:
#! /bin/sh
:
cat > /dev/null
mailx -s 'Yep, gone fishing' \"$SENDER\" < $HOME/.fishing.msg
where the ``cat > /dev/null'' will read all input from the standard
input, preventing a write error on the pipeline command. Note that the
ignore_write_errors attribute is normally turned off in the pipe trans‐
port, thus any command which does not read the entire message from
stdin will cause mail to be returned to the sender stating that a write
error occurred on the pipe, usually with the cause ``Broken pipe''.
Similarly the ignore_status attribute is also normally off by default
and thus any pipe program that exits with a non-zero status will also
cause mail to be returned to the sender.
In the above script the variables shown are available from the com‐
mand's environment. See the smailtrns(5) manual page for list of the
available environment variables.
Also note that some value unique to the user should appear on the com‐
mand line. This will ensure that if a given message is delivered to
more than one user who uses the same command line then each will indeed
receive a copy. If the command lines were identical duplicate delivery
suppression done by smail would cause only one user to receive a copy
of the message.
The current list of private driver attributes for the forwardfile
driver is:
caution
type: string
This string defines a list of users and directories which should
cause addresses to be flagged with the caution bit.
Each entry in the list is expanded individually. If this string
expansion fails, it is ignored.
A number, or a number range (in the form low_number-high_number)
can be used to indicate numerical user-ID numbers that should be
treated with caution. Typically, this string is ``0'', thus pre‐
venting file and shell command from being performed as the supe‐
ruser, or ``0-99'' to prevent access with any so-called ``system''
ID.
checkowner
type: boolean
If set, then one of the permissible owners will be the user-ID
associated with the address (in addition to any listed in the own‐
ers attribute).
file
type: string
The name of a file containing the forward information for a user.
This string will be expanded with the local name passed to the
director available as $user and any associated home directory
available as $HOME. If this string expansion fails, it is ignored.
forwardto
type: boolean
If set, then the file must begin with ``Forward to '' to be consid‐
ered a forward file. Also, only the first line is scanned for
addresses. This ``feature'' mimics the capability found in some
systems for storing forwarding information in user mailboxes.
lock
type: boolean
Makes the director lock the file before reading it (assuming that
your Unix supports locking of files for reading).
modemask
type: number
A mode mask defining the maximum permissiveness allowed for the
permissions on a forward file. Analogous to the modemask attribute
for the aliasfile driver.
prefix
type: string
This attribute requires that an address begin with the specified
string to be matched by the director. Any use of the $user vari‐
able in the file or owner attribute will expand with this prefix
already removed.
suffix
type: string
This attribute requires that an address end with the specified
string to be matched by the director. Any use of the $user vari‐
able in the file or owner attribute will expand with this suffix
already removed.
Both a prefix and a suffix attribute can be specified for a for‐
wardfile director instance. In this case both the prefix and the
suffix strings are required to match for the director to match an
address.
owners
type: string
Specifies an optional colon-separated list of users who may own the
forward file (in addition to the user-ID associated with the
address if the checkowner attribute is also set).
owngroups
type: string
Specifies an optional colon-separated list of groups who may own
the forward file.
unsecure
type: string
This string defines a list of users and directories which should
cause addresses to be flagged with the unsecure bit. This will
prevent delivery to pipes or files. Each list entry is expanded.
If this string expansion fails, it is ignored. A number, or a num‐
ber range (in the form low_number-high_number) can be used to indi‐
cate numerical user-IDs that should be treated with caution.
If none of the attributes owners, owngroups, or checkowner is given, no
checks are made on ownership restrictions. The default modemask is 0,
effectively disabling checks for file mode restrictions.
NOTE: Unless the file attribute references $HOME or begins with the
string ``~/'' the forward file driver can be used to provide forward
files for users or names that are not listed in the passwd file. In
this case $user merely expands to the address passed to the forwardfile
driver. This feature can be used for setting up forwarding for obso‐
lete accounts or mailing list directories.
An example of useful forwardfile director entries are:
# Put forwarding addresses for obsolete accounts under
# the /u/obsolete directory. These will contain only
# forwarding addresses. This is maintained by users in
# the group "admin" or "staff".
#
obsolete:
driver=forwardfile;
file=/u/obsolete/$user,
owngroups=admin:staff
#
# Handle per-user forward files in each user's home
# directory. This is roughly compatible with BSD
# sendmail, though performs some access checks, and
# is very cautious of directories which are remotely
# accessible. ~/.forward entries for root, uucp, and
# daemon will operate from the nobody uid. Root may
# also own a user's ~/.forward file. The ~/.forward
# files must not be group or world writable.
#
dotforward:
driver=forwardfile, nobody;
file=~/.forward, unsecure=~uucp:~ftp,
caution=root:uucp:daemon, checkowner,
owners=root, modemask=022
#
# allow the "Forward to " feature to be used from user
# mailbox files as used in AT&T UNIX System V.
#
forwardto:
driver=forwardfile, nobody;
file=/usr/spool/mail/$user, caution=root,
checkowner, modemask=002
#
# define a mailing list directory, with any shell commands
# executed under the nobody user-ID. Any file in this
# directory defines the name and contents of a mailing list.
#
lists:
driver=forwardfile, caution, sender_okay,
owner="owner-${strip:lc:user}";
file=/usr/lib/smail/lists/${strip:lc:user}
The Mailing-list Drivers
Mailing-list drivers match addresses of the form
:include:/pathname/to/list/of/addresses
The mailing list file is given by the pathname following the :include:
prefix string.
Mailing-list drivers come in two forms, one form for mailing-lists
derived by aliasing drivers (aliasinclude), and another form for mail‐
ing-lists derived by forwarding drivers (forwardinclude). The reason
for having two forms is that security options take different forms
depending on where mailing-lists come from. Also, by having them sepa‐
rately recognised it is possible to allow pipes and files in mailing-
lists from alias files but not from forward files. Note that if a new
driver is written that does not comply to the standards for alias driv‐
ers and forwarding drivers, and that can produce mailing lists, a new
mailing-list driver may need to be written for it as well.
The format of a mailing list file is the same as that of a forward
file: a simple list of addresses, with optional comments.
The driver attributes are common to both of the mailing-list drivers:
copyowners
type: boolean
If set, attributes related to ownership restrictions are taken from
the director which produced the mailing list address.
copysecure
type: boolean
The modemask is copied from the director which produced the mailing
list address.
interval
type: number
The sleep interval, in seconds, between retries. For some systems
that have one second timing granularity, this number must be at
least 2 to guarantee a non-zero sleep interval.
match_director
type: string
Names the specific director that this entry matches expansions of.
This can be used to assign different attributes from alternate uses
of the aliasfile and forwardfile directors.
modemask
type: number
The maximum permissiveness of file modes.
owners
type: string
A list of allowed owners.
owngroups
type: string
A list of allowed owning groups.
retries
type: number
The maximum count of open retries.
The User Driver
The user director driver routes mail to local users. When the mailbox
name matches the username a director instance using this driver will
mark this address as fully-resolved and tag it with a transport name.
The user driver's attributes are:
prefix
type: string
The prefix attribute specifies a regular expression which must
match at the beginning of the mailbox name. The string matching
the prefix is removed from the mailbox name prior to determining if
the remaining string matches a valid username on the local host.
If the remaining part of the mailbox does match a local username
then the matching prefix string will be saved in the $user_prefix
variable, as well as being exported in the MBOX_PREFIX environment
variable by any transport using the pipe driver. Note that on sys‐
tems with POSIX RE libraries case is ignored if the ignore-case
attribute is set.
suffix
type: string
The suffix attribute specifies a regular expression which must
match at the end of the mailbox name. The string matching the suf‐
fix is removed from the mailbox name prior to determining if the
remaining string matches a valid username on the local host. If
the remaining part of the mailbox does match a local username then
the matching suffix string will be saved in the $user_suffix vari‐
able, as well as being exported in the MBOX_SUFFIX environment
variable by any transport using the pipe driver. Note that on sys‐
tems with POSIX RE libraries case is ignored if the ignore-case
attribute is set.
transport
type: string
The name of the transport instance to associate with an address if
this director matches the address to a local username.
ignore-case
type: boolean
If set, the user director driver ignores the case of the username
when matching. Note that names from the password file are lower‐
cased when they are inserted into the internal username cache, so
unless you wish to bounce mail when the address contains upper-case
characters, this attribute should always be set, and it is set by
default.
A typical user director entry in the director file is:
user: driver=user; transport=local
This will associate any mail destined for a user on the local host with
the local transport.
The AltUser Driver
The altuser director directs mail to a mailbox for known user on the
local host as per the user director, but using an alternate file with a
format like that of /etc/passwd. This file may be accessed by any of
the standard search methods, and so the interface looks just like that
of aliasfile. This director succeeds if the local address matches a
user in the alternate passwd file and will put an entry on the list of
fully-resolved addresses.
The driver attributes are:
pwfile
type: string
The name of a file which contains the key/value association data‐
base.
proto
type: string
Names the protocol used in opening and searching the database.
Possible values are bsearch, lsearch, or dbm , with the same mean‐
ings as for these attributes in the aliasfile driver.
modemask
type: number
A mask, ala umask(2), defining the maximum permissiveness allowed
for the permissions on the pwfile. For example, a modemask of 022
disallows write access to all but the file owner. This value
should be chosen to strike a reasonable compromise between security
and user convenience. If some of these bits are set, the secure
flag is not set for the related addresses. It should also take
into account the use of the owners and owngroups attributes
described below.
owners
type: string
A list of permissible owners for the pwfile. If the pwfile is
owned by another user, the caution bit is set for the returned
addresses.
owngroups
type: string
A list of permissible groups owners for the pwfile. If the pwfile
is owned by some other group, the caution bit is set for the
returned addresses.
retries
type: number
The maximum count of open(2) retries. This should be greater than
zero if the system does not have an atomic rename(2) system call,
as the pwfile may not always exist while being edited, etc.
interval
type: number
The sleep interval, in seconds, between retries of the pwfile open.
For systems that have one second timing granularity, this number
must be at least 2 to guarantee a non-zero sleep interval.
The private driver attribute flags are:
reopen
type: boolean
If this attribute is on, the alias file will be closed and reopened
after each call to the driver. This is useful for systems that
have a shortage of file descriptors yet wish to access a large num‐
ber of databases.
tryagain
type: boolean
If set, then if the open fails, the resolution of local addresses
will be attempted at a later time. This is useful in a networking
environment where failure to open a database may be a result of a
server machine being down or temporarily inaccessible.
The Smartuser Driver
It may be that you wish all local addresses that you don't recognise to
be sent elsewhere. For example, there could be a host in your domain
that knows where most of the domain's users reside. The smartuser
driver is a convenient way of handling this case, by redirecting mail
for unknown users to another host. Note that this must be the last
director entry, if it is used, because it is generally non-discrimina‐
tory.
The possible driver attributes for the smartuser driver are:
new_user
type: string
This defines the new address to direct mail to. This string will
be string expanded with $user set to the local address name, and
with $HOME being any the associated home directory, if there is
one. It is a configuration error for this string expansion to
fail.
It is possible to set the new_user value in the config file. This
is done by setting the config attribute called smart_user to a
valid e-mail address, possibly including an expansion of the $user
variable. For example, the config file could contain the following
line:
smart_user = $user@gateway.domain
WARNING: Do not forget the quoting rules if you set smart_user to
a pipe command. The contents of variables such as $user, $sender,
etc., are under the control of the remote user. If this string is
passed to the pipe transport and thus to a shell command line it is
extremely important that expansion of these variables be very care‐
fully protected by proper shell quoting.
For example:
new_user="|/local/sbin/phquery -f ${shquote:sender} ${shquote:user}"
Note also that if this command is itself a script it must also
treat the values of these arguments as potentially containing meta
characters and such. Similarly for any program which may pass
these values on to another via another shell comamnd line.
well_formed_only
type: boolean
If set, the smartuser driver only matches an address if it contains
characters exclusively from the set of letters, digits, whitespace,
as well as `-', `_', `+', and `.'.
If the well_formed_only attribute is on, any use of the $user vari‐
able in the new_user value will have any groups of one or more
whitespace characters or ``.'' characters collapsed into exactly
one dot. If it is off, the $user value may be enclosed in double-
quotes, with backslash escapes where appropriate. This prevents
the the value of $user from changing the form of the address.
transport
type: string
If set, this defines a transport that unknown user's mail is passed
to. This would be useful for either passing to a program that
really can deliver the mail, or alternatively specifying a trans‐
port (probably a piped program), which can generate a more detailed
error message and help information than the default smail diagnos‐
tics. The well_formed_only and new_user attributes work as
detailed above - if no new user is specified by either new_user or
the system smartuser configurations, then the user is passed on
unchanged.
prefix
type: string
The prefix attribute specifies a regular expression which must
match at the beginning of the mailbox name. the matching prefix
string will be saved in the $user_prefix variable, as well as being
exported in the MBOX_PREFIX environment variable by any transport
using the pipe driver. Note that on systems with POSIX RE
libraries case of the prefix string is ignored.
suffix
type: string
The suffix attribute specifies a regular expression which must
match at the end of the mailbox name. The matching suffix string
will be saved in the $user_suffix variable, as well as being
exported in the MBOX_SUFFIX environment variable by any transport
using the pipe driver. Note that on systems with POSIX RE
libraries case of the suffix string is ignored.
A sample entry is:
smartuser:
driver=smartuser;
new_user=$user@gateway.domain,
well_formed_only
With this entry, the input addresses:
john
and
John Q. Public
will become:
john@gateway.domain
and
John.Q.Public@gateway.domain
respectively. If well_formed_only had not been set, the second address
would have been:
"John Q. Public"@gateway.domain
whereas the input address:
\unusual"address"in\deed
would become:
"\\unusual\"address\"in\\deed"@gateway.domain
Addresses which are produced by the smartuser driver are flagged as
such and will not themselves be matched by the smartuser driver. Thus,
infinite loops will not occur if ``gateway.domain,'' from the example,
happens to be the local host.
DEFAULT CONFIGURATION
The default internal directors configuration can be viewed by typing
smail -oD /no-such-file -v -bP DIRECTORS
The default director configuration is normally something like this:
aliasinclude
a director using the aliasinclude driver. The owner address is
set to ``owner-${lc:user}'' to send bounces to a specified mail‐
box instead of to the sender (since the address the sender spec‐
ified was fine and valid, and since only the person responsible
for the alias can fix it).
forwardinclude
a director using the forwardinclude driver.
aliases
a director using the aliasfile driver with an alias database
stored as an ASCII text file in /etc/aliases. The owner address
is set to ``owner-${lc:user}'' to send bounces to a specified
mailbox instead of to the sender (since the address the sender
specified was fine and valid, and since only the person respon‐
sible for the alias can fix it).
dotforward
a director using the forwardfile driver for forwarding informa‐
tion stored in user home directories in the file .forward. The
owner address is set to ``real-$user'' to prevent forwarding
loops with bounces (see the real_user director below).
user a director using the user driver to match local users for deliv‐
ery using the local transport.
real_user
a director using the user driver which matches local usernames
after stripping a prefix of ``real-'' from the mailbox name (and
thus bypassing further matching by the dotforward and aliases
directors) so that mail can be guaranteed to be delivered to a
local user on a specific host. Delivery is done using the local
transport.
lists a director using the forwardfile driver to deliver to mailing
lists stored in the directory /etc/smail/lists/. The owner
address is set to ``owner-${lc:user}'' to send bounces to a
specified mailbox instead of the sender or the entire list.
owner a director using the smartuser driver which matches only
addresses with a prefix of ``owner-'' and which rewrites those
which match to ``postmaster''. Note that this is only a last-
ditch catch-all director since normally owner addresses which
cannot be verified will default to ``postmaster'' anyway.
smart_user
a director using the smartuser driver, but normally without a
new_user or transport specified directly.
FILES
/etc/smail/directors
Optional configuration for smail directors, i.e., configured meth‐
ods for resolving local addresses. This file replaces the com‐
piled-in director configuration.
/var/log/smail/logfile
A log of smail transactions.
/var/log/smail/paniclog
A log of configuration or system errors encountered by smail.
SEE ALSOsmail(5). smailconf(5), smailmeth(5), smailqual(5), smailrtrs(5),
smailrtry(5), smailtrns(5), smail(8). Smail Administration and Instal‐
lation Guide. DARPA Internet Requests for Comments RFC 821, RFC 822,
RFC 974, RFC 976, and RFC 1123.
Regular expression documentation for your host, perhaps in re_for‐
mat(7), regex(3), ed(1), or grep(1).
BUGS
Colons cannot be included in the value of a list element.
Database files cannot contain ``#'' in the left-hand field.
COPYRIGHT
Copyright (C) 1987, 1988 Ronald S. Karr and Landon Curt Noll
Copyright (C) 1992 Ronald S. Karr
See a file COPYING, distributed with the source code, or type smail
-bc, to view distribution rights and restrictions associated with this
software.
Smail-3 RELEASE-3_2_0_115 SMAILDRCT(5)
