1#++ 2# NAME 3# regexp_table 5 4# SUMMARY 5# format of Postfix regular expression tables 6# SYNOPSIS 7# \fBpostmap -q "\fIstring\fB" regexp:/etc/postfix/\fIfilename\fR 8# 9# \fBpostmap -q - regexp:/etc/postfix/\fIfilename\fB <\fIinputfile\fR 10# DESCRIPTION 11# The Postfix mail system uses optional tables for address 12# rewriting, mail routing, or access control. These tables 13# are usually in \fBdbm\fR or \fBdb\fR format. 14# 15# Alternatively, lookup tables can be specified in POSIX regular 16# expression form. In this case, each input is compared against a 17# list of patterns. When a match is found, the corresponding 18# result is returned and the search is terminated. 19# 20# To find out what types of lookup tables your Postfix system 21# supports use the "\fBpostconf -m\fR" command. 22# 23# To test lookup tables, use the "\fBpostmap -q\fR" command 24# as described in the SYNOPSIS above. Use "\fBpostmap -hmq 25# -\fR <\fIfile\fR" for header_checks(5) patterns, and 26# "\fBpostmap -bmq -\fR <\fIfile\fR" for body_checks(5) 27# (Postfix 2.6 and later). 28# COMPATIBILITY 29# .ad 30# .fi 31# With Postfix version 2.2 and earlier specify "\fBpostmap 32# -fq\fR" to query a table that contains case sensitive 33# patterns. Patterns are case insensitive by default. 34# TABLE FORMAT 35# .ad 36# .fi 37# The general form of a Postfix regular expression table is: 38# .IP "\fB/\fIpattern\fB/\fIflags result\fR" 39# When \fIpattern\fR matches the input string, 40# use the corresponding \fIresult\fR value. 41# .IP "\fB!/\fIpattern\fB/\fIflags result\fR" 42# When \fIpattern\fR does \fBnot\fR match the input string, 43# use the corresponding \fIresult\fR value. 44# .IP "\fBif /\fIpattern\fB/\fIflags\fR" 45# .IP "\fBendif\fR" 46# If the input string matches /\fIpattern\fR/, then match that 47# input string against the patterns between \fBif\fR and 48# \fBendif\fR. The \fBif\fR..\fBendif\fR can nest. 49# .sp 50# Note: do not prepend whitespace to patterns inside 51# \fBif\fR..\fBendif\fR. 52# .sp 53# This feature is available in Postfix 2.1 and later. 54# .IP "\fBif !/\fIpattern\fB/\fIflags\fR" 55# .IP "\fBendif\fR" 56# If the input string does not match /\fIpattern\fR/, then 57# match that input string against the patterns between \fBif\fR 58# and \fBendif\fR. The \fBif\fR..\fBendif\fR can nest. 59# .sp 60# Note: do not prepend whitespace to patterns inside 61# \fBif\fR..\fBendif\fR. 62# .sp 63# This feature is available in Postfix 2.1 and later. 64# .IP "blank lines and comments" 65# Empty lines and whitespace-only lines are ignored, as 66# are lines whose first non-whitespace character is a `#'. 67# .IP "multi-line text" 68# A logical line starts with non-whitespace text. A line that 69# starts with whitespace continues a logical line. 70# .PP 71# Each pattern is a POSIX regular expression enclosed by a pair of 72# delimiters. The regular expression syntax is documented in 73# \fBre_format\fR(7) with 4.4BSD, in \fBregex\fR(5) with Solaris, and in 74# \fBregex\fR(7) with Linux. Other systems may use other document names. 75# 76# The expression delimiter can be any non-alphanumerical 77# character, except whitespace 78# or characters that have special meaning (traditionally the forward 79# slash is used). The regular expression can contain whitespace. 80# 81# By default, matching is case-insensitive, and newlines are not 82# treated as special characters. The behavior is controlled by flags, 83# which are toggled by appending one or more of the following 84# characters after the pattern: 85# .IP "\fBi\fR (default: on)" 86# Toggles the case sensitivity flag. By default, matching is case 87# insensitive. 88# .IP "\fBm\fR (default: off)" 89# Toggle the multi-line mode flag. When this flag is on, the \fB^\fR 90# and \fB$\fR metacharacters match immediately after and immediately 91# before a newline character, respectively, in addition to 92# matching at the start and end of the input string. 93# .IP "\fBx\fR (default: on)" 94# Toggles the extended expression syntax flag. By default, support 95# for extended expression syntax is enabled. 96# TABLE SEARCH ORDER 97# .ad 98# .fi 99# Patterns are applied in the order as specified in the table, until a 100# pattern is found that matches the input string. 101# 102# Each pattern is applied to the entire input string. 103# Depending on the application, that string is an entire client 104# hostname, an entire client IP address, or an entire mail address. 105# Thus, no parent domain or parent network search is done, and 106# \fIuser@domain\fR mail addresses are not broken up into their 107# \fIuser\fR and \fIdomain\fR constituent parts, nor is \fIuser+foo\fR 108# broken up into \fIuser\fR and \fIfoo\fR. 109# TEXT SUBSTITUTION 110# .ad 111# .fi 112# Substitution of substrings (text that matches patterns 113# inside "()") from the matched expression into the result 114# string is requested with $1, $2, etc.; specify $$ to produce 115# a $ character as output. 116# The macros in the result string may need to be written as 117# ${n} or $(n) if they aren't followed by whitespace. 118# 119# Note: since negated patterns (those preceded by \fB!\fR) return a 120# result when the expression does not match, substitutions are not 121# available for negated patterns. 122# EXAMPLE SMTPD ACCESS MAP 123# # Disallow sender-specified routing. This is a must if you relay mail 124# # for other domains. 125# /[%!@].*[%!@]/ 550 Sender-specified routing rejected 126# 127# # Postmaster is OK, that way they can talk to us about how to fix 128# # their problem. 129# /^postmaster@/ OK 130# 131# # Protect your outgoing majordomo exploders 132# if !/^owner-/ 133# /^(.*)-outgoing@(.*)$/ 550 Use ${1}@${2} instead 134# endif 135# EXAMPLE HEADER FILTER MAP 136# # These were once common in junk mail. 137# /^Subject: make money fast/ REJECT 138# /^To: friend@public\\.com/ REJECT 139# EXAMPLE BODY FILTER MAP 140# # First skip over base 64 encoded text to save CPU cycles. 141# ~^[[:alnum:]+/]{60,}$~ OK 142# 143# # Put your own body patterns here. 144# SEE ALSO 145# postmap(1), Postfix lookup table manager 146# pcre_table(5), format of PCRE tables 147# cidr_table(5), format of CIDR tables 148# README FILES 149# .ad 150# .fi 151# Use "\fBpostconf readme_directory\fR" or 152# "\fBpostconf html_directory\fR" to locate this information. 153# .na 154# .nf 155# DATABASE_README, Postfix lookup table overview 156# AUTHOR(S) 157# The regexp table lookup code was originally written by: 158# LaMont Jones 159# lamont@hp.com 160# 161# That code was based on the PCRE dictionary contributed by: 162# Andrew McNamara 163# andrewm@connect.com.au 164# connect.com.au Pty. Ltd. 165# Level 3, 213 Miller St 166# North Sydney, NSW, Australia 167# 168# Adopted and adapted by: 169# Wietse Venema 170# IBM T.J. Watson Research 171# P.O. Box 704 172# Yorktown Heights, NY 10598, USA 173# 174# Wietse Venema 175# Google, Inc. 176# 111 8th Avenue 177# New York, NY 10011, USA 178#-- 179