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diff --git a/man/man5/pcre_table.5 b/man/man5/pcre_table.5 new file mode 100644 index 0000000..a9fd7b6 --- /dev/null +++ b/man/man5/pcre_table.5 @@ -0,0 +1,275 @@ +.TH PCRE_TABLE 5 +.ad +.fi +.SH NAME +pcre_table +\- +format of Postfix PCRE tables +.SH "SYNOPSIS" +.na +.nf +\fBpostmap \-q "\fIstring\fB" pcre:/etc/postfix/\fIfilename\fR + +\fBpostmap \-q \- pcre:/etc/postfix/\fIfilename\fB <\fIinputfile\fR + +\fBpostmap \-hmq \- pcre:/etc/postfix/\fIfilename\fB <\fIinputfile\fR + +\fBpostmap \-bmq \- pcre:/etc/postfix/\fIfilename\fB <\fIinputfile\fR +.SH DESCRIPTION +.ad +.fi +The Postfix mail system uses optional tables for address +rewriting, mail routing, or access control. These tables +are usually in \fBdbm\fR or \fBdb\fR format. + +Alternatively, lookup tables can be specified in Perl Compatible +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 "\fBpostconf \-m\fR" command. + +To test lookup tables, use the "\fBpostmap \-q\fR" command +as described in the SYNOPSIS above. Use "\fBpostmap \-hmq +\-\fR <\fIfile\fR" for header_checks(5) patterns, and +"\fBpostmap \-bmq \-\fR <\fIfile\fR" for body_checks(5) +(Postfix 2.6 and later). + +This driver can be built with the pcre2 library (Postfix +3.7 and later), or with the legacy pcre library (all Postfix +versions). +.SH "COMPATIBILITY" +.na +.nf +.ad +.fi +With Postfix version 2.2 and earlier specify "\fBpostmap +\-fq\fR" to query a table that contains case sensitive +patterns. Patterns are case insensitive by default. +.SH "TABLE FORMAT" +.na +.nf +.ad +.fi +The general form of a PCRE table is: +.IP "\fB/\fIpattern\fB/\fIflags result\fR" +When \fIpattern\fR matches the input string, use +the corresponding \fIresult\fR value. +.IP "\fB!/\fIpattern\fB/\fIflags result\fR" +When \fIpattern\fR does \fBnot\fR match the input string, use +the corresponding \fIresult\fR value. +.IP "\fBif /\fIpattern\fB/\fIflags\fR" +.IP "\fBendif\fR" +If the input string matches /\fIpattern\fR/, then match that +input string against the patterns between \fBif\fR and +\fBendif\fR. The \fBif\fR..\fBendif\fR can nest. +.sp +Note: do not prepend whitespace to patterns inside +\fBif\fR..\fBendif\fR. +.sp +This feature is available in Postfix 2.1 and later. +.IP "\fBif !/\fIpattern\fB/\fIflags\fR" +.IP "\fBendif\fR" +If the input string does not match /\fIpattern\fR/, then +match that input string against the patterns between \fBif\fR +and \fBendif\fR. The \fBif\fR..\fBendif\fR can nest. +.sp +Note: do not prepend whitespace to patterns inside +\fBif\fR..\fBendif\fR. +.sp +This feature is available in Postfix 2.1 and later. +.IP "blank lines and comments" +Empty lines and whitespace\-only lines are ignored, as +are lines whose first non\-whitespace character is a `#'. +.IP "multi\-line text" +A logical line starts with non\-whitespace text. A line that +starts with whitespace continues a logical line. +.PP +Each pattern is a perl\-like regular expression. The expression +delimiter can be any non\-alphanumeric 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: +.IP "\fBi\fR (default: on)" +Toggles the case sensitivity flag. By default, matching is case +insensitive. +.IP "\fBm\fR (default: off)" +Toggles the pcre MULTILINE flag. When this flag is on, the \fB^\fR +and \fB$\fR metacharacters match immediately after and immediately +before a newline character, respectively, in addition to +matching at the start and end of the subject string. +.IP "\fBs\fR (default: on)" +Toggles the pcre DOTALL flag. When this flag is on, the \fB.\fR +metacharacter matches the newline character. With +Postfix versions prior to 2.0, the flag is off by +default, which is inconvenient for multi\-line message header +matching. +.IP "\fBx\fR (default: off)" +Toggles the pcre extended flag. When this flag is on, whitespace +characters in the pattern (other than in a character class) +are ignored. To include a whitespace character as part of +the pattern, escape it with backslash. +.sp +Note: do not use \fB#\fIcomment\fR after patterns. +.IP "\fBA\fR (default: off)" +Toggles the pcre ANCHORED flag. When this flag is on, +the pattern is forced to be "anchored", that is, it is +constrained to match only at the start of the string which +is being searched (the "subject string"). This effect can +also be achieved by appropriate constructs in the pattern +itself. +.IP "\fBE\fR (default: off)" +Toggles the pcre DOLLAR_ENDONLY flag. When this flag is on, +a \fB$\fR metacharacter in the pattern matches only at the +end of the subject string. Without this flag, a dollar also +matches immediately before the final character if it is a +newline character (but not before any other newline +characters). This flag is ignored if the pcre MULTILINE +flag is set. +.IP "\fBU\fR (default: off)" +Toggles the pcre UNGREEDY flag. When this flag is on, +the pattern matching engine inverts the "greediness" of +the quantifiers so that they are not greedy by default, +but become greedy if followed by "?". This flag can also +set by a (?U) modifier within the pattern. +.IP "\fBX\fR (default: off)" +Toggles the pcre EXTRA flag. +When this flag is on, any backslash in a pattern that is +followed by a letter that has no special meaning causes an +error, thus reserving these combinations for future expansion. + +This feature is not supported with PCRE2. +.SH "SEARCH ORDER" +.na +.nf +.ad +.fi +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 +\fIuser@domain\fR mail addresses are not broken up into their +\fIuser\fR and \fIdomain\fR constituent parts, nor is \fIuser+foo\fR +broken up into \fIuser\fR and \fIfoo\fR. +.SH "TEXT SUBSTITUTION" +.na +.nf +.ad +.fi +Substitution of substrings (text that matches patterns +inside "()") from the matched expression into the result +string is requested with $1, $2, etc.; specify $$ to produce +a $ character as output. +The macros in the result string may need to be written as +${n} or $(n) if they aren't followed by whitespace. +This feature does not support pcre2 substring names. + +Note: since negated patterns (those preceded by \fB!\fR) return a +result when the expression does not match, substitutions are not +available for negated patterns. +.SH "INLINE SPECIFICATION" +.na +.nf +.ad +.fi +The contents of a table may be specified in the table name +(Postfix 3.7 and later). +The basic syntax is: + +.nf +main.cf: + \fIparameter\fR \fB= .. pcre:{ { \fIrule\-1\fB }, { \fIrule\-2\fB } .. } ..\fR + +master.cf: + \fB.. \-o { \fIparameter\fR \fB= .. pcre:{ { \fIrule\-1\fB }, { \fIrule\-2\fB } .. } .. } ..\fR +.fi + +Postfix ignores whitespace after '{' and before '}', and +writes each \fIrule\fR as one text line to an in\-memory +file: + +.nf +in\-memory file: + rule\-1 + rule\-2 + .. +.fi + +Postfix parses the result as if it is a file in /etc/postfix. + +Note: if a rule contains \fB$\fR, specify \fB$$\fR to keep +Postfix from trying to do \fI$name\fR expansion as it +evaluates a parameter value. +.SH "EXAMPLE SMTPD ACCESS MAP" +.na +.nf +# Protect your outgoing majordomo exploders +/^(?!owner\-)(.*)\-outgoing@(.*)/ 550 Use ${1}@${2} instead + +# Bounce friend@whatever, except when whatever is our domain (you would +# be better just bouncing all friend@ mail \- this is just an example). +/^(friend@(?!my\\.domain$).*)$/ 550 Stick this in your pipe $1 + +# A multi\-line entry. The text is sent as one line. +# +/^noddy@my\\.domain$/ +\ 550 This user is a funny one. You really don't want to send mail to +\ them as it only makes their head spin. +.SH "EXAMPLE HEADER FILTER MAP" +.na +.nf +/^Subject: make money fast/ REJECT +/^To: friend@public\\.com/ REJECT +.SH "EXAMPLE BODY FILTER MAP" +.na +.nf +# First skip over base 64 encoded text to save CPU cycles. +# Requires PCRE version 3. +~^[[:alnum:]+/]{60,}$~ OK + +# Put your own body patterns here. +.SH "SEE ALSO" +.na +.nf +postmap(1), Postfix lookup table manager +postconf(5), configuration parameters +regexp_table(5), format of POSIX regular expression tables +.SH "README FILES" +.na +.nf +.ad +.fi +Use "\fBpostconf readme_directory\fR" or +"\fBpostconf html_directory\fR" to locate this information. +.na +.nf +DATABASE_README, Postfix lookup table overview +.SH "AUTHOR(S)" +.na +.nf +The PCRE table lookup code was originally written 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 |