SOCKETMAP_TABLE(5)                                          SOCKETMAP_TABLE(5)

NAME
       socketmap_table - Postfix socketmap table lookup client

SYNOPSIS
       postmap -q "string" socketmap:inet:host:port:name
       postmap -q "string" socketmap:unix:pathname:name

       postmap -q - socketmap:inet:host:port:name <inputfile
       postmap -q - socketmap:unix:pathname:name <inputfile

DESCRIPTION
       The  Postfix  mail  system  uses optional tables for address rewriting,
       mail routing or policy lookup.

       The Postfix socketmap client expects TCP endpoint  names  of  the  form
       inet:host:port:name,  or  UNIX-domain  endpoints of the form unix:path-
       name:name.  In both cases, name specifies the name field in a socketmap
       client request (see "REQUEST FORMAT" below).

PROTOCOL
       Socketmaps use a simple protocol: the client sends one request, and the
       server sends one reply.  Each request and each reply are  sent  as  one
       netstring object.

REQUEST FORMAT
       The  socketmap  protocol supports only the lookup request.  The request
       has the following form:

       name <space> key
              Search the named socketmap for the specified key.

       Postfix will not generate partial search  keys  such  as  domain  names
       without  one  or more subdomains, network addresses without one or more
       least-significant octets, or email  addresses  without  the  localpart,
       address  extension  or domain portion. This behavior is also found with
       cidr:, pcre:, and regexp: tables.

REPLY FORMAT
       Replies must have the following form:

       OK <space> data
              The requested data was found.

       NOTFOUND <space>
              The requested data was not found.

       TEMP <space> reason

       TIMEOUT <space> reason

       PERM <space> reason
              The request failed. The reason,  if  non-empty,  is  descriptive
              text.

PROTOCOL LIMITS
       The  Postfix  socketmap client requires that replies are no longer than
       100000 bytes (not including the netstring  encapsulation).  This  limit
       can  be changed with the socketmap_max_reply_size configuration parame-
       ter (Postfix 3.10 and later).

       The Postfix socketmap client enforces a 100s time limit to connect to a
       socketmap  server, to send a request, and to receive a reply. It closes
       an idle connection after 10s, and closes  an  active  connection  after
       100s. These limits are not (yet) configurable.

SECURITY
       This  map  cannot  be  used for security-sensitive information, because
       neither the connection nor the server are authenticated.

CONFIGURATION PARAMETERS
       socketmap_max_reply_size (100000)
              The maximum allowed reply size  from  a  socketmap  server,  not
              including the netstring encapsulation.

SEE ALSO
       https://cr.yp.to/proto/netstrings.txt, netstring definition
       postconf(1), Postfix supported lookup tables
       postmap(1), Postfix lookup table manager
       regexp_table(5), format of regular expression tables
       pcre_table(5), format of PCRE tables
       cidr_table(5), format of CIDR tables

README FILES
       DATABASE_README, Postfix lookup table overview

BUGS
       The protocol time limits are not yet configurable.

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

HISTORY
       Socketmap support was introduced with Postfix version 2.10.

       The socketmap protocol was published with Sendmail v8.13.

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

       Wietse Venema
       Google, Inc.
       111 8th Avenue
       New York, NY 10011, USA

       Wietse Venema
       porcupine.org

                                                            SOCKETMAP_TABLE(5)