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diff --git a/man/man5/aliases.5 b/man/man5/aliases.5 new file mode 100644 index 0000000..1140d49 --- /dev/null +++ b/man/man5/aliases.5 @@ -0,0 +1,231 @@ +.TH ALIASES 5 +.ad +.fi +.SH NAME +aliases +\- +Postfix local alias database format +.SH "SYNOPSIS" +.na +.nf +.fi +\fBnewaliases\fR +.SH DESCRIPTION +.ad +.fi +The \fBaliases\fR(5) table provides a system\-wide mechanism to +redirect mail for local recipients. The redirections are +processed by the Postfix \fBlocal\fR(8) delivery agent. + +Normally, the \fBaliases\fR(5) table is specified as a text file +that serves as input to the \fBpostalias\fR(1) command. The +result, an indexed file in \fBdbm\fR or \fBdb\fR format, is +used for fast lookup by the mail system. Execute the command +\fBnewaliases\fR in order to rebuild the indexed file after +changing the Postfix alias database. + +When the table is provided via other means such as NIS, LDAP +or SQL, the same lookups are done as for ordinary indexed files. + +Alternatively, the table can be provided as a regular\-expression +map where patterns are given as regular expressions. In +this case, the lookups are done in a slightly different way +as described below under "REGULAR EXPRESSION TABLES". + +Users can control delivery of their own mail by setting +up \fB.forward\fR files in their home directory. +Lines in per\-user \fB.forward\fR files have the same syntax +as the right\-hand side of \fBaliases\fR(5) entries. + +The format of the alias database input file is as follows: +.IP \(bu +An alias definition has the form +.sp +.nf + \fIname\fR: \fIvalue1\fR, \fIvalue2\fR, \fI...\fR +.fi +.IP \(bu +Empty lines and whitespace\-only lines are ignored, as +are lines whose first non\-whitespace character is a `#'. +.IP \(bu +A logical line starts with non\-whitespace text. A line that +starts with whitespace continues a logical line. +.PP +The \fIname\fR is a local address (no domain part). +Use double quotes when the name contains any special characters +such as whitespace, `#', `:', or `@'. The \fIname\fR is folded to +lowercase, in order to make database lookups case insensitive. +.PP +In addition, when an alias exists for \fBowner\-\fIname\fR, +this will override the envelope sender address, so that +delivery diagnostics are directed to \fBowner\-\fIname\fR, +instead of the originator of the message (for details, see +\fBowner_request_special\fR, \fBexpand_owner_alias\fR and +\fBreset_owner_alias\fR). +This is typically used to direct delivery errors to the maintainer of +a mailing list, who is in a better position to deal with mailing +list delivery problems than the originator of the undelivered mail. +.PP +The \fIvalue\fR contains one or more of the following: +.IP \fIaddress\fR +Mail is forwarded to \fIaddress\fR, which is compatible +with the RFC 822 standard. +.IP \fI/file/name\fR +Mail is appended to \fI/file/name\fR. See \fBlocal\fR(8) +for details of delivery to file. +Delivery is not limited to regular files. For example, to dispose +of unwanted mail, deflect it to \fB/dev/null\fR. +.IP "|\fIcommand\fR" +Mail is piped into \fIcommand\fR. Commands that contain special +characters, such as whitespace, should be enclosed between double +quotes. See \fBlocal\fR(8) for details of delivery to command. +.sp +When the command fails, a limited amount of command output is +mailed back to the sender. The file \fB/usr/include/sysexits.h\fR +defines the expected exit status codes. For example, use +\fB"|exit 67"\fR to simulate a "user unknown" error, and +\fB"|exit 0"\fR to implement an expensive black hole. +.IP \fB:include:\fI/file/name\fR +Mail is sent to the destinations listed in the named file. +Lines in \fB:include:\fR files have the same syntax +as the right\-hand side of alias entries. +.sp +A destination can be any destination that is described in this +manual page. However, delivery to "|\fIcommand\fR" and +\fI/file/name\fR is disallowed by default. To enable, edit the +\fBallow_mail_to_commands\fR and \fBallow_mail_to_files\fR +configuration parameters. +.SH "ADDRESS EXTENSION" +.na +.nf +.ad +.fi +When alias database search fails, and the recipient localpart +contains the optional recipient delimiter (e.g., \fIuser+foo\fR), +the search is repeated for the unextended address (e.g., \fIuser\fR). + +The \fBpropagate_unmatched_extensions\fR parameter controls +whether an unmatched address extension (\fI+foo\fR) is +propagated to the result of table lookup. +.SH "CASE FOLDING" +.na +.nf +.ad +.fi +The local(8) delivery agent always folds the search string +to lowercase before database lookup. +.SH "REGULAR EXPRESSION TABLES" +.na +.nf +.ad +.fi +This section describes how the table lookups change when the table +is given in the form of regular expressions. For a description of +regular expression lookup table syntax, see \fBregexp_table\fR(5) +or \fBpcre_table\fR(5). NOTE: these formats do not use ":" at the +end of a pattern. + +Each regular expression is applied to the entire search +string. Thus, a search string \fIuser+foo\fR is not broken +up into \fIuser\fR and \fIfoo\fR. + +Regular expressions are applied in the order as specified +in the table, until a regular expression is found that +matches the search string. + +Lookup results are the same as with indexed file lookups. +For security reasons there is no support for \fB$1\fR, +\fB$2\fR etc. substring interpolation. +.SH "SECURITY" +.na +.nf +.ad +.fi +The \fBlocal\fR(8) delivery agent disallows regular expression +substitution of $1 etc. in \fBalias_maps\fR, because that +would open a security hole. + +The \fBlocal\fR(8) delivery agent will silently ignore +requests to use the \fBproxymap\fR(8) server within +\fBalias_maps\fR. Instead it will open the table directly. +Before Postfix version 2.2, the \fBlocal\fR(8) delivery +agent will terminate with a fatal error. +.SH "CONFIGURATION PARAMETERS" +.na +.nf +.ad +.fi +The following \fBmain.cf\fR parameters are especially relevant. +The text below provides only a parameter summary. See +\fBpostconf\fR(5) for more details including examples. +.IP "\fBalias_database (see 'postconf -d' output)\fR" +The alias databases for \fBlocal\fR(8) delivery that are updated with +"\fBnewaliases\fR" or with "\fBsendmail \-bi\fR". +.IP "\fBalias_maps (see 'postconf -d' output)\fR" +The alias databases that are used for \fBlocal\fR(8) delivery. +.IP "\fBallow_mail_to_commands (alias, forward)\fR" +Restrict \fBlocal\fR(8) mail delivery to external commands. +.IP "\fBallow_mail_to_files (alias, forward)\fR" +Restrict \fBlocal\fR(8) mail delivery to external files. +.IP "\fBexpand_owner_alias (no)\fR" +When delivering to an alias "\fIaliasname\fR" that has an +"owner\-\fIaliasname\fR" companion alias, set the envelope sender +address to the expansion of the "owner\-\fIaliasname\fR" alias. +.IP "\fBpropagate_unmatched_extensions (canonical, virtual)\fR" +What address lookup tables copy an address extension from the lookup +key to the lookup result. +.IP "\fBowner_request_special (yes)\fR" +Enable special treatment for owner\-\fIlistname\fR entries in the +\fBaliases\fR(5) file, and don't split owner\-\fIlistname\fR and +\fIlistname\fR\-request address localparts when the recipient_delimiter +is set to "\-". +.IP "\fBrecipient_delimiter (empty)\fR" +The set of characters that can separate a user name from its +extension (example: user+foo), or a .forward file name from its +extension (example: .forward+foo). +.PP +Available in Postfix version 2.3 and later: +.IP "\fBfrozen_delivered_to (yes)\fR" +Update the \fBlocal\fR(8) delivery agent's idea of the Delivered\-To: +address (see prepend_delivered_header) only once, at the start of +a delivery attempt; do not update the Delivered\-To: address while +expanding aliases or .forward files. +.SH "STANDARDS" +.na +.nf +RFC 822 (ARPA Internet Text Messages) +.SH "SEE ALSO" +.na +.nf +local(8), local delivery agent +newaliases(1), create/update alias database +postalias(1), create/update alias database +postconf(5), configuration parameters +.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 "LICENSE" +.na +.nf +.ad +.fi +The Secure Mailer license must be distributed with this software. +.SH "AUTHOR(S)" +.na +.nf +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 |