    ACCESS(5)                                               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 expres-
           sions.  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 pre-
                  vious 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.

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    ACCESS(5)                                               ACCESS(5)

                  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 appli-
           cation, 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.

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    ACCESS(5)                                               ACCESS(5)

    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

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