SOCKETMAP_TABLE(5) File Formats Manual 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 with-
out one or more subdomains, network addresses without one or more
least-significant octets, or email addresses without the localpart, ad-
dress 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 parameter
(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 nei-
ther the connection nor the server are authenticated.
CONFIGURATION PARAMETERS
socketmap_max_reply_size (100000)
The maximum allowed reply size from a socketmap server, not in-
cluding 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
Use "postconf readme_directory" or "postconf html_directory" to locate
this information.
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)
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