# 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.
# 
#        For an example, see the EXAMPLE section at the end of this
#        manual page.
# 
#        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 input format for the postmap(1) command 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,  patterns  are
#        tried in the order as listed below:
# 
#        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  (note that this is the default
#               for some versions of Postfix).  Otherwise,  specify
#               .domain.tld  (note  the  initial  dot)  in order to
#               match subdomains.
# 
#        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.
# 
# ACCEPT ACTIONS
#        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.
# 
# REJECT ACTIONS
#        4NN text
# 
#        5NN text
#               Reject  the  address etc. that matches the pattern,
#               and respond with the numerical three-digit code and
#               text.  4NN means "try again later", while 5NN means
#               "do not try again".
# 
#        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.
# 
#        DEFER_IF_REJECT optional text...
#               Defer  the  request if some later restriction would
#               result in a REJECT action. Reply with "450 optional
#               text... when the optional text is specified, other-
#               wise reply with a generic error response message.
# 
#               This feature is available in Postfix 2.1 and later.
# 
#        DEFER_IF_PERMIT optional text...
#               Defer  the  request if some later restriction would
#               result in a an explicit or implicit PERMIT  action.
#               Reply  with "450 optional text... when the optional
#               text is specified, otherwise reply with  a  generic
#               error response message.
# 
#               This feature is available in Postfix 2.1 and later.
# 
# OTHER ACTIONS
#        restriction...
#               Apply the named UCE restriction(s) (permit, reject,
#               reject_unauth_destination, and so on).
# 
#        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.
# 
#               This feature is available in Postfix 2.0 and later.
# 
#        DUNNO  Pretend  that  the  lookup  key was not found. This
#               prevents Postfix  from  trying  substrings  of  the
#               lookup  key (such as a subdomain name, or a network
#               address subnetwork).
# 
#               This feature is available in Postfix 2.0 and later.
# 
#        FILTER transport:destination
#               After  the  message is queued, send the entire mes-
#               sage through the specified external content filter.
#               The  transport:destination  syntax  is described in
#               the transport(5)  manual  page.   More  information
#               about  external  content  filters is in the Postfix
#               FILTER_README file.
# 
#               Note:  this  action  overrides  the  main.cf   con-
#               tent_filter  setting,  and  currently  affects  all
#               recipients of the message.
# 
#               This feature is available in Postfix 2.0 and later.
# 
#        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.
# 
#               This feature is available in Postfix 2.0 and later.
# 
#        PREPEND headername: headervalue
#               Prepend the specified message header  to  the  mes-
#               sage.  When this action is used multiple times, the
#               first prepended header appears  before  the  second
#               etc. prepended header.
# 
#               Note:  this action does not support multi-line mes-
#               sage headers.
# 
#               This feature is available in Postfix 2.1 and later.
# 
#        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.
# 
#               This feature is available in Postfix 2.1 and later.
# 
#        WARN optional text...
#               Log a warning with the optional text, together with
#               client information and  if  available,  with  helo,
#               sender, recipient and protocol information.
# 
#               This feature is available in Postfix 2.1 and later.
# 
# 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).   This  feature  is not available in Postfix
#        version 2.1.
# 
#        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.
# 
# EXAMPLE
#        The following example uses an indexed file,  so  that  the
#        order  of  table entries does not matter. The example per-
#        mits access by the client at address 1.2.3.4  but  rejects
#        all  other clients in 1.2.3.0/24. Instead of "hash" lookup
#        tables, some systems use "dbm".  Use the command "postconf
#        -m"  to  find  out  what lookup tables Postfix supports on
#        your system.
# 
#        /etc/postfix/main.cf:
#            smtpd_client_restrictions =
#                check_client_access hash:/etc/postfix/access
# 
#        /etc/postfix/access:
#            1.2.3   REJECT
#            1.2.3.4 OK
# 
#        Execute the command "postmap /etc/postfix/access" after
#        editing the file.
# 
# BUGS
#        The table format does not understand quoting  conventions.
# 
# SEE ALSO
#        postmap(1), Postfix lookup table manager
#        smtpd(8), SMTP server
#        postconf(5), configuration parameters
#        transport(5), transport:nexthop syntax
# 
# README FILES
#        Use  "postconf  readme_directory" or "postconf html_direc-
#        tory" to locate this information.
#        SMTPD_ACCESS_README, built-in SMTP server access control
#        DATABASE_README, Postfix lookup table overview
# 
# 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)
