.\" $OpenBSD: table.5,v 1.14 2024/05/02 18:14:33 op Exp $ .\" .\" Copyright (c) 2013 Eric Faurot .\" Copyright (c) 2013 Gilles Chehade .\" .\" Permission to use, copy, modify, and distribute this software for any .\" purpose with or without fee is hereby granted, provided that the above .\" copyright notice and this permission notice appear in all copies. .\" .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. .\" .\" .Dd $Mdocdate: May 2 2024 $ .Dt TABLE 5 .Os .Sh NAME .Nm table .Nd format description for smtpd tables .Sh DESCRIPTION This manual page documents the file format for the various tables used in the .Xr smtpd 8 mail daemon. .Pp The format described here applies to tables as defined in .Xr smtpd.conf 5 . .Sh TABLE TYPES There are two types of tables: lists and mappings. A list consists of a series of values, while a mapping consists of a series of keys and their associated values. The following illustrates how to declare them as static tables: .Bd -literal -offset indent table mylist { value1, value2, value3 } table mymapping { key1 = value1, key2 = value2, key3 = value3 } .Ed .Pp When using a .Ql file table, a list will be written with each value on a line by itself. .Bd -literal -offset indent value1 value2 value3 .Ed .Pp A mapping will be written with each key and value on a line, whitespace and an optional colon separating both columns: .Bd -literal -offset indent key1: value1 key2 value2 key3 value3 .Ed .Pp Blank lines, leading and trailing spaces and tabs are ignored. Lines whose first non-space character is a hash mark .Pq Sq # are comments and are ignored. To force the parsing of a file table as a list rather than a mapping, use this special comment: .Pp .Dl # @list .Pp A file table can be converted to a Berkeley database using the .Xr makemap 8 utility with no syntax change. .Pp Tables using a .Ql file or Berkeley DB backend will be referenced as follows: .Bd -unfilled -offset indent .Ic table Ar name Cm file : Ns Pa /path/to/file .Ic table Ar name Cm db : Ns Pa /path/to/file.db .Ed .Ss Aliasing tables Aliasing tables are mappings that associate a recipient to one or many destinations. They can be used in two contexts: primary domain aliases and virtual domain mapping. .Bd -unfilled -offset indent .Ic action Ar name method Cm alias Pf < table Ns > .Ic action Ar name method Cm virtual Pf < table Ns > .Ed .Pp In a primary domain context, the key is the user part of the recipient address, whilst the value is one or many recipients as described in .Xr aliases 5 : .Bd -literal -offset indent user1 otheruser user2 otheruser1,otheruser2 user3 otheruser@example.com .Ed .Pp In a virtual domain context, the key is either a user part, a full email address or a catch-all, following selection rules described in .Xr smtpd.conf 5 , and the value is one or many recipients as described in .Xr aliases 5 : .Bd -literal -offset indent user1 otheruser user2@example.org otheruser1,otheruser2 @example.org otheruser@example.com @ catchall@example.com .Ed .Pp The following directive shares the same table format, but with a different meaning. Here, the user is allowed to send mail from the listed addresses: .Bd -unfilled -offset indent .Ic listen on Ar interface Cm auth Oo Ar ... Oc Cm senders Pf < Ar table Ns > .Ed .Ss Domain tables Domain tables are simple lists of domains or hosts. .Bd -unfilled -offset indent .Ic match Cm for domain Pf < table Ns > Cm action Ar name .Ic match Cm helo Pf < table Ns > Oo Ar ... Oc Cm action Ar name .Ed .Pp In that context, the list of domains will be matched against the recipient domain or against the HELO name advertised by the sending host, respectively. For .Ql static , .Ql file and .Xr dbopen 3 backends, a wildcard may be used so the domain table may contain: .Bd -literal -offset indent example.org *.example.org .Ed .Ss Credentials tables Credentials tables are mappings of credentials. They can be used in two contexts: .Bd -unfilled -offset indent .Ic listen on Ar interface Cm tls Oo Ar ... Oc Cm auth Pf < Ar table Ns > .Ic action Ar name Cm relay host Ar relay-url Cm auth Pf < Ar table Ns > .Ed .Pp In a listener context, the credentials are a mapping of username and encrypted passwords: .Bd -literal -offset indent user1 $2b$10$hIJ4QfMcp.90nJwKqGbKM.MybArjHOTpEtoTV.DgLYAiThuoYmTSe user2 $2b$10$bwSmUOBGcZGamIfRuXGTvuTo3VLbPG9k5yeKNMBtULBhksV5KdGsK .Ed .Pp The passwords are to be encrypted using the .Xr smtpctl 8 encrypt subcommand. .Pp In a relay context, the credentials are a mapping of labels and username:password pairs: .Bd -literal -offset indent label1 user:password .Ed .Pp The label must be unique and is used as a selector for the proper credentials when multiple credentials are valid for a single destination. The password is not encrypted as it must be provided to the remote host. .Ss Netaddr tables Netaddr tables are lists of IPv4 and IPv6 network addresses. They can only be used in the following context: .Pp .D1 Ic match Cm from src Pf < Ar table Ns > Cm action Ar name .Pp When used as a "from source", the address of a client is compared to the list of addresses in the table until a match is found. .Pp A netaddr table can contain exact addresses or netmasks, and looks as follow: .Bd -literal -offset indent 192.168.1.1 [::1] 192.168.1.0/24 .Ed .Pp IPv6 addresses must be enclosed in square brackets. .Ss Userinfo tables Userinfo tables are used in rule context to specify an alternate userbase, mapping virtual users to local system users by UID, GID and home directory. .Pp .D1 Ic action Ar name method Cm userbase Pf < Ar table Ns > .Pp A userinfo table looks as follows: .Bd -literal -offset indent joe 1000:100:/home/virtual/joe jack 1000:100:/home/virtual/jack .Ed .Pp In this example, both joe and jack are virtual users mapped to the local system user with UID 1000 and GID 100, but different home directories. These directories may contain a .Xr forward 5 file. This can be used in conjunction with an alias table that maps an email address or the domain part to the desired virtual username. For example: .Bd -literal -offset indent joe@example.org joe jack@example.com jack .Ed .Ss Source tables Source tables are lists of IPv4 and IPv6 addresses. They can only be used in the following context: .Pp .D1 Ic action Ar name Cm relay src Pf < Ar table Ns > .Pp Successive queries to the source table will return the elements one by one. .Pp A source table looks as follow: .Bd -literal -offset indent 192.168.1.2 192.168.1.3 [::1] [::2] .Ed .Pp IPv6 address must be enclosed in square brackets. .Ss Mailaddr tables Mailaddr tables are lists of email addresses. They can be used in the following contexts: .Bd -unfilled -offset indent .Ic match Cm mail\-from Pf < Ar table Ns > Cm action Ar name .Ic match Cm rcpt\-to Pf < Ar table Ns > Cm action Ar name .Ed .Pp A mailaddr entry is used to match an email address against a username, a domain or a full email address. A "*" wildcard may be used in part of the domain name. .Pp A mailaddr table looks as follow: .Bd -literal -offset indent user @domain user@domain user@*.domain .Ed .Ss Addrname tables Addrname tables are used to map IP addresses to hostnames. They can be used in both listen context and relay context: .Bd -unfilled -offset indent .Ic listen on Ar interface Cm hostnames Pf < Ar table Ns > .Ic action Ar name Cm relay helo\-src Pf < Ar table Ns > .Ed .Pp In listen context, the table is used to look up the server name to advertise depending on the local address of the socket on which a connection is accepted. In relay context, the table is used to determine the hostname for the HELO sequence of the SMTP protocol, depending on the local address used for the outgoing connection. .Pp The format is a mapping from inet4 or inet6 addresses to hostnames: .Bd -literal -offset indent [::1] localhost 127.0.0.1 localhost 88.190.23.165 www.opensmtpd.org .Ed .Pp IPv6 addresses must be enclosed in square brackets. .Sh SEE ALSO .Xr smtpd.conf 5 , .Xr makemap 8 , .Xr smtpd 8