ACCESS(5)

NAME
access - format of Postfix access table

SYNOPSIS
postmap /etc/postfix/access

DESCRIPTION
The optional access table directs the Postfix SMTP server to selectively reject or accept mail from or to specific hosts, domains, networks, host addresses or mail addresses. Normally, the access table is specified as a text file that serves as input to the postmap(1) command. The result, an indexed file in dbm or db format, is used for fast searching by the mail system. Execute the command postmap /etc/postfix/access in order to rebuild the indexed file after changing the access table. When the table is provided via other means such as NIS, LDAP or SQL, the same lookups are done as for ordinary indexed files. Alternatively, the table can be provided as a regular-expression map where patterns are given as regular expressions. In that case, the lookups are done in a slightly different way as described below.

TABLE FORMAT
The format of the access table is as follows:

blanks and comments
    Blank lines are ignored, as are lines beginning with `#'.

leading whitespace
    Lines that begin with whitespace continue the previous line.

pattern action
    When pattern matches a mail address, domain or host address, perform the corresponding action.

PATTERNS
With lookups from indexed files such as DB or DBM, or from networked tables such as NIS, LDAP or SQL, patterns are tried in the order as listed below:

user@domain
    Matches the specified mail address.

domain.name
    Matches the domain.name itself and any subdomain thereof, either in hostnames or in mail addresses. Top-level domains will never be matched.

user@
    Matches all mail addresses with the specified user part.

net.work.addr.ess

net.work.addr

net.work

net Matches any host address in the specified network. A network address is a sequence of one or more octets separated by ".".

ACTIONS

[45]NN text
    Reject the address etc. that matches the pattern, and respond with the numerical code and text.

REJECT
    Reject the address etc. that matches the pattern. A generic error response message is generated.

OK  Accept the address etc. that matches the pattern.

restriction...
    Apply the named UCE restriction(s) (permit, reject, reject_unauth_destination, and so on).

REGULAR EXPRESSION TABLES
This section describes how the table lookups change when the table is given in the form of regular expressions. For a description of regular expression lookup table syntax, see regexp_table(5) or pcre_table(5). Each pattern is a regular expression that is applied to the entire string being looked up. Depending on the application, that string is an entire client hostname, an entire client IP address, or an entire mail address. Thus, no parent domain or parent network search is done, and user@domain mail addresses are not broken up into their user@ and domain constituent parts. Patterns are applied in the order as specified in the table, until a pattern is found that matches the search string. Actions are the same as with normal indexed file lookups, with the additional feature that parenthesized substrings from the pattern can be interpolated as $1, $2 and so on.

BUGS
The table format does not understand quoting conventions.

SEE ALSO
postmap(1) create mapping table
smtpd(8) smtp server
pcre_table(5) format of PCRE tables
regexp_table(5) format of POSIX regular expression tables

LICENSE
The Secure Mailer license must be distributed with this software.

AUTHOR(S)
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA