#++ # NAME # aliases 5 # SUMMARY # Postfix local alias database format # SYNOPSIS # .fi # \fBnewaliases\fR # DESCRIPTION # 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. # ADDRESS EXTENSION # .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. # CASE FOLDING # .ad # .fi # The local(8) delivery agent always folds the search string # to lowercase before database lookup. # REGULAR EXPRESSION TABLES # .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. # SECURITY # .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. # CONFIGURATION PARAMETERS # .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 an email address # localpart, user name, or a .forward file name from its extension. # .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. # STANDARDS # RFC 822 (ARPA Internet Text Messages) # SEE ALSO # local(8), local delivery agent # newaliases(1), create/update alias database # postalias(1), create/update alias database # postconf(5), configuration parameters # README FILES # .ad # .fi # Use "\fBpostconf readme_directory\fR" or # "\fBpostconf html_directory\fR" to locate this information. # .na # .nf # DATABASE_README, Postfix lookup table overview # LICENSE # .ad # .fi # The Secure Mailer license must be distributed with this software. # 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 #--