tcp_table(5)

1TCP_TABLE(5)                  File Formats Manual                 TCP_TABLE(5)
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NAME

6       tcp_table - Postfix client/server table lookup protocol
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SYNOPSIS

9       postmap -q "string" tcp:host:port
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11       postmap -q - tcp:host:port <inputfile
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DESCRIPTION

14       The  Postfix  mail system uses optional tables for address rewriting or
15       mail routing. These tables are usually in dbm or  db  format.  Alterna‐
16       tively, table lookups can be directed to a TCP server.
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18       To  find  out  what types of lookup tables your Postfix system supports
19       use the "postconf -m" command.
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21       To test lookup tables, use the "postmap -q" command as described in the
22       SYNOPSIS above.
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PROTOCOL DESCRIPTION

25       The TCP map class implements a very simple protocol: the client sends a
26       request, and the server sends one reply. Requests and replies are  sent
27       as  one  line of ASCII text, terminated by the ASCII newline character.
28       Request and reply parameters (see below) are separated by whitespace.
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30       Send and receive operations must complete in 100 seconds.
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REQUEST FORMAT

33       The tcp_table protocol supports only the lookup request.   The  request
34       has the following form:
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36       get SPACE key NEWLINE
37              Look up data under the specified key.
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39       Postfix  will  not  generate  partial  search keys such as domain names
40       without one or more subdomains, network addresses without one  or  more
41       least-significant  octets,  or  email  addresses without the localpart,
42       address extension or domain portion. This behavior is also  found  with
43       cidr:, pcre:, and regexp: tables.
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REPLY FORMAT

46       Each  reply specifies a status code and text. Replies must be no longer
47       than 4096 characters including the newline terminator.
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49       500 SPACE text NEWLINE
50              In case of a lookup request, the requested data does not  exist.
51              The text describes the nature of the problem.
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53       400 SPACE text NEWLINE
54              This indicates an error condition. The text describes the nature
55              of the problem. The client should retry the request later.
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57       200 SPACE text NEWLINE
58              The request was successful. In the case of a lookup request, the
59              text contains an encoded version of the requested data.
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ENCODING

62       In  request  and  reply  parameters, the character %, each non-printing
63       character, and each whitespace character must be replaced by %XX, where
64       XX is the corresponding ASCII hexadecimal character value. The hexadec‐
65       imal codes can be specified in any case (upper, lower, mixed).
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67       The Postfix client always encodes a request.  The server may  omit  the
68       encoding  as  long  as  the reply is guaranteed to not contain the % or
69       NEWLINE character.
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SECURITY

72       Do not use TCP lookup  tables  for  security  critical  purposes.   The
73       client-server connection is not protected and the server is not authen‐
74       ticated.
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BUGS

77       Only the lookup method is currently implemented.
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79       The client does not hang up when the connection  is  idle  for  a  long
80       time.
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README FILES

89       Use  "postconf readme_directory" or "postconf html_directory" to locate
90       this information.
91       DATABASE_README, Postfix lookup table overview
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LICENSE

94       The Secure Mailer license must be distributed with this software.
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AUTHOR(S)

97       Wietse Venema
98       IBM T.J. Watson Research
99       P.O. Box 704
100       Yorktown Heights, NY 10598, USA
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102       Wietse Venema
103       Google, Inc.
104       111 8th Avenue
105       New York, NY 10011, USA
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