    ACCESS(5)                                               ACCESS(5)

    NAME
           access - format of Postfix access table

    SYNOPSIS
           postmap /etc/postfix/access

           postmap -q "string" /etc/postfix/access

           postmap -q - /etc/postfix/access <inputfile

    DESCRIPTION
           The  optional access table directs the Postfix SMTP server
           to selectively  reject  or  accept  mail.  Access  can  be
           allowed  or  denied for specific host names, domain names,
           networks, host network 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,  or lookups can be directed to TCP-based server. In
           that case, the lookups are done in  a  slightly  different
           way  as  described below under "REGULAR EXPRESSION TABLES"
           and "TCP-BASED TABLES".

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

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

           blank lines and comments
                  Empty  lines and whitespace-only lines are ignored,
                  as are lines whose first  non-whitespace  character
                  is a `#'.

           multi-line text
                  A  logical  line starts with non-whitespace text. A
                  line that starts with whitespace continues a  logi-
                  cal line.

    EMAIL ADDRESS PATTERNS
           With lookups from indexed files such as DB or DBM, or from
           networked tables such as NIS, LDAP or SQL,  the  following
           lookup patterns are examined in the order as listed:

           user@domain
                  Matches the specified mail address.

           domain.tld
                  Matches  domain.tld  as the domain part of an email
                  address.

                  The pattern domain.tld also matches subdomains, but
                  only when the string smtpd_access_maps is listed in
                  the Postfix  parent_domain_matches_subdomains  con-
                  figuration setting.  Otherwise, specify .domain.tld
                  (note the initial dot) in  order  to  match  subdo-
                  mains.

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

           Note: lookup of the null sender address  is  not  possible
           with  some types of lookup table. By default, Postfix uses
           <> as the lookup key for  such  addresses.  The  value  is
           specified  with the smtpd_null_access_lookup_key parameter
           in the Postfix main.cf file.

    EMAIL ADDRESS EXTENSION
           When a mail address localpart contains the optional recip-
           ient  delimiter  (e.g., user+foo@domain), the lookup order
           becomes: user+foo@domain, user@domain, domain,  user+foo@,
           and user@.

    HOST NAME/ADDRESS PATTERNS
           With lookups from indexed files such as DB or DBM, or from
           networked tables such as NIS, LDAP or SQL,  the  following
           lookup patterns are examined in the order as listed:

           domain.tld
                  Matches domain.tld.

                  The pattern domain.tld also matches subdomains, but
                  only when the string smtpd_access_maps is listed in
                  the  Postfix  parent_domain_matches_subdomains con-
                  figuration setting.  Otherwise, specify .domain.tld
                  (note  the  initial  dot)  in order to match subdo-
                  mains.

           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 ".".

                  NOTE: use the cidr lookup  table  type  to  specify
                  network/netmask  patterns.  See  cidr_table(5)  for
                  details.

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

           REJECT

           REJECT optional text...
                  Reject  the  address etc. that matches the pattern.
                  Reply with $reject_code optional text...  when  the
                  optional  text is specified, otherwise reply with a
                  generic error response message.

           OK     Accept the address etc. that matches the pattern.

           all-numerical
                  An all-numerical result is treated as OK. This for-
                  mat  is generated by address-based relay authoriza-
                  tion schemes.

           DUNNO  Pretend that the lookup key was not found  in  this
                  table. This prevents Postfix from trying substrings
                  of the lookup key (such as a subdomain name,  or  a
                  network address subnetwork).

           HOLD

           HOLD optional text...
                  Place  the message on the hold queue, where it will
                  sit until someone either deletes it or releases  it
                  for  delivery.  Log the optional text if specified,
                  otherwise log a generic message.

                  Mail that is placed on hold can  be  examined  with
                  the  postcat(1)  command,  and  can be destroyed or
                  released with the postsuper(1) command.

                  Note: this action currently affects all  recipients
                  of the message.

           DISCARD

           DISCARD optional text...
                  Claim  successful delivery and silently discard the
                  message.  Log the optional text if specified,  oth-
                  erwise log a generic message.

                  Note:  this action currently affects all recipients
                  of the message.

           FILTER transport:destination
                  After the message is queued, send the  entire  mes-
                  sage  through  a  content filter.  More information
                  about  content  filters  is  in  the  Postfix  FIL-
                  TER_README file.

                  Note:   this  action  overrides  the  main.cf  con-
                  tent_filter  setting,  and  currently  affects  all
                  recipients of the message.

           REDIRECT user@domain
                  After  the  message  is queued, send the message to
                  the  specified  address  instead  of  the  intended
                  recipient(s).

                  Note:  this action overrides the FILTER action, and
                  currently affects all recipients of the message.

           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,
           user@domain  mail  addresses  are not broken up into their
           user@ and domain constituent parts, nor is user+foo broken
           up into user and foo.

           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 indexed file lookups, with
           the additional feature that parenthesized substrings  from
           the pattern can be interpolated as $1, $2 and so on.

    TCP-BASED TABLES
           This  section  describes how the table lookups change when
           lookups are directed to a TCP-based server. For a descrip-
           tion   of  the  TCP  client/server  lookup  protocol,  see
           tcp_table(5).

           Each lookup operation uses the entire query  string  once.
           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, user@domain mail addresses are not  broken
           up  into  their user@ and domain constituent parts, nor is
           user+foo broken up into user and foo.

           Actions are the same as with indexed file lookups.

    BUGS
           The table format does not understand quoting  conventions.

    SEE ALSO
           postmap(1) create lookup table
           smtpd(8) smtp server
           cidr_table(5) format of CIDR tables
           pcre_table(5) format of PCRE tables
           regexp_table(5) format of POSIX regular expression tables
           tcp_table(5) TCP client/server table lookup protocol

    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

                                                            ACCESS(5)