postmap -q "string" regexp:/etc/postfix/filename postmap -q - regexp:/etc/postfix/filename <inputfile
Alternatively, lookup tables can be specified in POSIX regular expression form. In this case, each input is compared against a list of patterns. When a match is found, the corresponding result is returned and the search is terminated.
To find out what types of lookup tables your Postfix system supports use the "postconf -m" command.
To test lookup tables, use the "postmap -q" command as described in the SYNOPSIS above. Use "postmap -hmq - <file" for header_checks(5) patterns, and "postmap -bmq - <file" for body_checks(5) (Postfix 2.6 and later).
With Postfix version 2.2 and earlier specify "postmap -fq" to query a table that contains case sensitive patterns. Patterns are case insensitive by default.
The general form of a Postfix regular expression table is:
Note: do not prepend whitespace to patterns inside if..endif.
This feature is available in Postfix 2.1 and later.
Note: do not prepend whitespace to patterns inside if..endif.
This feature is available in Postfix 2.1 and later.
Each pattern is a POSIX regular expression enclosed by a pair of delimiters. The regular expression syntax is documented in re_format(7) with 4.4BSD, in regex(5) with Solaris, and in regex(7) with Linux. Other systems may use other document names.
The expression delimiter can be any non-alphanumerical character, except whitespace or characters that have special meaning (traditionally the forward slash is used). The regular expression can contain whitespace.
By default, matching is case-insensitive, and newlines are not treated as special characters. The behavior is controlled by flags, which are toggled by appending one or more of the following characters after the pattern:
Patterns are applied in the order as specified in the table, until a pattern is found that matches the input string.
Each pattern is applied to the entire input string. 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, and 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.
Substitution of substrings (text that matches patterns inside "()") from the matched expression into the result string is requested with $1, $2, etc.; specify $$ to produce a $ character as output. The macros in the result string may need to be written as ${n} or $(n) if they aren't followed by whitespace.
Note: since negated patterns (those preceded by !) return a result when the expression does not match, substitutions are not available for negated patterns.
# Disallow sender-specified routing. This is a must if you relay mail
# for other domains.
/[%!@].*[%!@]/ 550 Sender-specified routing rejected
# Postmaster is OK, that way they can talk to us about how to fix
# their problem.
/^postmaster@/ OK
# Protect your outgoing majordomo exploders
if !/^owner-/
/^(.*)-outgoing@(.*)$/ 550 Use ${1}@${2} instead
endif
# These were once common in junk mail. /^Subject: make money fast/ REJECT /^To: friend@public\.com/ REJECT
# First skip over base 64 encoded text to save CPU cycles.
~^[[:alnum:]+/]{60,}$~ OK
# Put your own body patterns here.
postmap(1), Postfix lookup table manager pcre_table(5), format of PCRE tables cidr_table(5), format of CIDR tables
Use "postconf readme_directory" or "postconf html_directory" to locate this information.
DATABASE_README, Postfix lookup table overview
The regexp table lookup code was originally written by: LaMont Jones lamont@hp.com That code was based on the PCRE dictionary contributed by: Andrew McNamara andrewm@connect.com.au connect.com.au Pty. Ltd. Level 3, 213 Miller St North Sydney, NSW, Australia Adopted and adapted by: 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