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7CANONICAL(5)                                                      CANONICAL(5)
8
9<b>NAME</b>
10       canonical - Postfix canonical table format
11
12<b>SYNOPSIS</b>
13       <b>postmap /etc/postfix/canonical</b>
14
15       <b>postmap -q "</b><i>string</i><b>" /etc/postfix/canonical</b>
16
17       <b>postmap -q - /etc/postfix/canonical</b> &lt;<i>inputfile</i>
18
19<b>DESCRIPTION</b>
20       The  optional <a href="canonical.5.html"><b>canonical</b>(5)</a> table specifies an address mapping for local
21       and non-local addresses. The mapping is used by the <a href="cleanup.8.html"><b>cleanup</b>(8)</a>  daemon,
22       before  mail  is  stored into the queue.  The address mapping is recur-
23       sive.
24
25       Normally, the <a href="canonical.5.html"><b>canonical</b>(5)</a> table is  specified  as  a  text  file  that
26       serves as input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command.  The result, an indexed file
27       in <b>dbm</b> or <b>db</b> format, is used for fast searching  by  the  mail  system.
28       Execute  the  command  "<b>postmap  /etc/postfix/canonical</b>"  to rebuild an
29       indexed file after changing the corresponding text file.
30
31       When the table is provided via other means such as NIS,  LDAP  or  SQL,
32       the same lookups are done as for ordinary indexed files.
33
34       Alternatively,  the  table  can be provided as a regular-expression map
35       where patterns are given as regular  expressions,  or  lookups  can  be
36       directed to a TCP-based server. In those cases, the lookups are done in
37       a slightly different way as described below under  "REGULAR  EXPRESSION
38       TABLES" or "TCP-BASED TABLES".
39
40       By  default  the  <a href="canonical.5.html"><b>canonical</b>(5)</a>  mapping  affects  both  message  header
41       addresses (i.e. addresses that  appear  inside  messages)  and  message
42       envelope  addresses  (for  example, the addresses that are used in SMTP
43       protocol commands).  This  is  controlled  with  the  <b><a href="postconf.5.html#canonical_classes">canonical_classes</a></b>
44       parameter.
45
46       NOTE:  Postfix  versions  2.2  and  later  rewrite message headers from
47       remote SMTP clients only if the  client  matches  the  <a href="postconf.5.html#local_header_rewrite_clients">local_header_re</a>-
48       <a href="postconf.5.html#local_header_rewrite_clients">write_clients</a> parameter, or if the <a href="postconf.5.html#remote_header_rewrite_domain">remote_header_rewrite_domain</a> config-
49       uration parameter specifies a non-empty  value.  To  get  the  behavior
50       before    Postfix    2.2,   specify   "<a href="postconf.5.html#local_header_rewrite_clients">local_header_rewrite_clients</a>   =
51       <a href="DATABASE_README.html#types">static</a>:all".
52
53       Typically, one would use the <a href="canonical.5.html"><b>canonical</b>(5)</a> table to replace login  names
54       by <i>Firstname.Lastname</i>, or to clean up addresses produced by legacy mail
55       systems.
56
57       The <a href="canonical.5.html"><b>canonical</b>(5)</a> mapping is not to be confused with <i>virtual alias</i>  sup-
58       port  or  with  local  aliasing.  To change the destination but not the
59       headers, use the <a href="virtual.5.html"><b>virtual</b>(5)</a> or <a href="aliases.5.html"><b>aliases</b>(5)</a> map instead.
60
61<b>CASE FOLDING</b>
62       The search string is folded to lowercase before database lookup. As  of
63       Postfix  2.3,  the search string is not case folded with database types
64       such as <a href="regexp_table.5.html">regexp</a>: or <a href="pcre_table.5.html">pcre</a>: whose lookup fields can match both  upper  and
65       lower case.
66
67<b>TABLE FORMAT</b>
68       The input format for the <a href="postmap.1.html"><b>postmap</b>(1)</a> command is as follows:
69
70       <i>pattern address</i>
71              When  <i>pattern</i>  matches  a mail address, replace it by the corre-
72              sponding <i>address</i>.
73
74       blank lines and comments
75              Empty lines and whitespace-only lines are ignored, as are  lines
76              whose first non-whitespace character is a `#'.
77
78       multi-line text
79              A  logical  line  starts  with  non-whitespace text. A line that
80              starts with whitespace continues a logical line.
81
82<b>TABLE SEARCH ORDER</b>
83       With lookups from indexed files such as DB or DBM,  or  from  networked
84       tables  such  as  NIS,  LDAP  or SQL, each <i>user</i>@<i>domain</i> query produces a
85       sequence of query patterns as described below.
86
87       Each query pattern is sent to each specified lookup table before trying
88       the next query pattern, until a match is found.
89
90       <i>user</i>@<i>domain address</i>
91              Replace <i>user</i>@<i>domain</i> by <i>address</i>. This form has the highest prece-
92              dence.
93
94              This is useful to clean up addresses  produced  by  legacy  mail
95              systems.   It  can  also  be  used to produce <i>Firstname.Lastname</i>
96              style addresses, but see below for a simpler solution.
97
98       <i>user address</i>
99              Replace <i>user</i>@<i>site</i> by <i>address</i> when <i>site</i> is  equal  to  $<b><a href="postconf.5.html#myorigin">myorigin</a></b>,
100              when  <i>site</i>  is listed in $<b><a href="postconf.5.html#mydestination">mydestination</a></b>, or when it is listed in
101              $<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b> or $<b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a></b>.
102
103              This form is useful for replacing login names by <i>Firstname.Last-</i>
104              <i>name</i>.
105
106       @<i>domain address</i>
107              Replace other addresses in <i>domain</i> by <i>address</i>.  This form has the
108              lowest precedence.
109
110              Note: @<i>domain</i> is a wild-card.  When  this  form  is  applied  to
111              recipient  addresses,  the  Postfix SMTP server accepts mail for
112              any recipient in <i>domain</i>, regardless of  whether  that  recipient
113              exists.   This  may  turn  your  mail  system into a backscatter
114              source: Postfix first accepts mail for  non-existent  recipients
115              and  then  tries  to  return that mail as "undeliverable" to the
116              often forged sender address.
117
118              To avoid backscatter with mail for a wild-card  domain,  replace
119              the  wild-card  mapping  with  explicit  1:1  mappings, or add a
120              <a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipient</a> restriction for that domain:
121
122                  <a href="postconf.5.html#smtpd_recipient_restrictions">smtpd_recipient_restrictions</a> =
123                      ...
124                      <a href="postconf.5.html#reject_unauth_destination">reject_unauth_destination</a>
125                      <a href="postconf.5.html#check_recipient_access">check_recipient_access</a>
126                          <a href="DATABASE_README.html#types">inline</a>:{example.com=<a href="postconf.5.html#reject_unverified_recipient">reject_unverified_recipient</a>}
127                  <a href="postconf.5.html#unverified_recipient_reject_code">unverified_recipient_reject_code</a> = 550
128
129              In the above example, Postfix may contact a remote server if the
130              recipient is rewritten to a remote address.
131
132<b>RESULT ADDRESS REWRITING</b>
133       The lookup result is subject to address rewriting:
134
135       <b>o</b>      When  the  result  has the form @<i>otherdomain</i>, the result becomes
136              the same <i>user</i> in <i>otherdomain</i>.
137
138       <b>o</b>      When "<b><a href="postconf.5.html#append_at_myorigin">append_at_myorigin</a>=yes</b>", append "<b>@$<a href="postconf.5.html#myorigin">myorigin</a></b>" to  addresses
139              without "@domain".
140
141       <b>o</b>      When "<b><a href="postconf.5.html#append_dot_mydomain">append_dot_mydomain</a>=yes</b>", append "<b>.$<a href="postconf.5.html#mydomain">mydomain</a></b>" to addresses
142              without ".domain".
143
144<b>ADDRESS EXTENSION</b>
145       When a mail address localpart contains the optional recipient delimiter
146       (e.g.,  <i>user+foo</i>@<i>domain</i>),  the  lookup  order becomes: <i>user+foo</i>@<i>domain</i>,
147       <i>user</i>@<i>domain</i>, <i>user+foo</i>, <i>user</i>, and @<i>domain</i>.
148
149       The  <b><a href="postconf.5.html#propagate_unmatched_extensions">propagate_unmatched_extensions</a></b>  parameter  controls   whether   an
150       unmatched address extension (<i>+foo</i>) is propagated to the result of table
151       lookup.
152
153<b>REGULAR EXPRESSION TABLES</b>
154       This section describes how the table lookups change when the  table  is
155       given  in the form of regular expressions. For a description of regular
156       expression lookup table syntax, see <a href="regexp_table.5.html"><b>regexp_table</b>(5)</a> or <a href="pcre_table.5.html"><b>pcre_table</b>(5)</a>.
157
158       Each pattern is a regular expression that  is  applied  to  the  entire
159       address  being looked up. Thus, <i>user@domain</i> mail addresses are not bro-
160       ken up into their <i>user</i> and <i>@domain</i> constituent parts, nor  is  <i>user+foo</i>
161       broken up into <i>user</i> and <i>foo</i>.
162
163       Patterns  are  applied  in the order as specified in the table, until a
164       pattern is found that matches the search string.
165
166       Results are the same as with indexed file lookups, with the  additional
167       feature  that parenthesized substrings from the pattern can be interpo-
168       lated as <b>$1</b>, <b>$2</b> and so on.
169
170<b>TCP-BASED TABLES</b>
171       This section describes how the table lookups change  when  lookups  are
172       directed   to  a  TCP-based  server.  For  a  description  of  the  TCP
173       client/server lookup protocol, see <a href="tcp_table.5.html"><b>tcp_table</b>(5)</a>.  This feature  is  not
174       available up to and including Postfix version 2.4.
175
176       Each  lookup operation uses the entire address once.  Thus, <i>user@domain</i>
177       mail addresses are not broken up  into  their  <i>user</i>  and  <i>@domain</i>  con-
178       stituent parts, nor is <i>user+foo</i> broken up into <i>user</i> and <i>foo</i>.
179
180       Results are the same as with indexed file lookups.
181
182<b>BUGS</b>
183       The table format does not understand quoting conventions.
184
185<b>CONFIGURATION PARAMETERS</b>
186       The  following  <a href="postconf.5.html"><b>main.cf</b></a>  parameters  are especially relevant.  The text
187       below provides only a  parameter  summary.  See  <a href="postconf.5.html"><b>postconf</b>(5)</a>  for  more
188       details including examples.
189
190       <b><a href="postconf.5.html#canonical_classes">canonical_classes</a>  (envelope_sender, envelope_recipient, header_sender,</b>
191       <b>header_recipient)</b>
192              What addresses are subject to <a href="postconf.5.html#canonical_maps">canonical_maps</a> address mapping.
193
194       <b><a href="postconf.5.html#canonical_maps">canonical_maps</a> (empty)</b>
195              Optional  address  mapping lookup tables for message headers and
196              envelopes.
197
198       <b><a href="postconf.5.html#recipient_canonical_maps">recipient_canonical_maps</a> (empty)</b>
199              Optional address mapping lookup tables for envelope  and  header
200              recipient addresses.
201
202       <b><a href="postconf.5.html#sender_canonical_maps">sender_canonical_maps</a> (empty)</b>
203              Optional  address  mapping lookup tables for envelope and header
204              sender addresses.
205
206       <b><a href="postconf.5.html#propagate_unmatched_extensions">propagate_unmatched_extensions</a> (canonical, virtual)</b>
207              What address lookup tables copy an address  extension  from  the
208              lookup key to the lookup result.
209
210       Other parameters of interest:
211
212       <b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b>
213              The  network  interface addresses that this mail system receives
214              mail on.
215
216       <b><a href="postconf.5.html#local_header_rewrite_clients">local_header_rewrite_clients</a> (<a href="postconf.5.html#permit_inet_interfaces">permit_inet_interfaces</a>)</b>
217              Rewrite message header addresses in mail from these clients  and
218              update incomplete addresses with the domain name in $<a href="postconf.5.html#myorigin">myorigin</a> or
219              $<a href="postconf.5.html#mydomain">mydomain</a>; either  don't  rewrite  message  headers  from  other
220              clients at all, or rewrite message headers and update incomplete
221              addresses with the domain  specified  in  the  <a href="postconf.5.html#remote_header_rewrite_domain">remote_header_re</a>-
222              <a href="postconf.5.html#remote_header_rewrite_domain">write_domain</a> parameter.
223
224       <b><a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a> (empty)</b>
225              The  network  interface addresses that this mail system receives
226              mail on by way of a proxy or network address translation unit.
227
228       <b><a href="postconf.5.html#masquerade_classes">masquerade_classes</a> (envelope_sender, header_sender, header_recipient)</b>
229              What addresses are subject to address masquerading.
230
231       <b><a href="postconf.5.html#masquerade_domains">masquerade_domains</a> (empty)</b>
232              Optional list of  domains  whose  subdomain  structure  will  be
233              stripped off in email addresses.
234
235       <b><a href="postconf.5.html#masquerade_exceptions">masquerade_exceptions</a> (empty)</b>
236              Optional  list  of  user names that are not subjected to address
237              masquerading,  even  when  their   addresses   match   $<a href="postconf.5.html#masquerade_domains">masquer</a>-
238              <a href="postconf.5.html#masquerade_domains">ade_domains</a>.
239
240       <b><a href="postconf.5.html#mydestination">mydestination</a> ($<a href="postconf.5.html#myhostname">myhostname</a>, localhost.$<a href="postconf.5.html#mydomain">mydomain</a>, localhost)</b>
241              The  list of domains that are delivered via the $<a href="postconf.5.html#local_transport">local_transport</a>
242              mail delivery transport.
243
244       <b><a href="postconf.5.html#myorigin">myorigin</a> ($<a href="postconf.5.html#myhostname">myhostname</a>)</b>
245              The domain name that locally-posted mail appears to  come  from,
246              and that locally posted mail is delivered to.
247
248       <b><a href="postconf.5.html#owner_request_special">owner_request_special</a> (yes)</b>
249              Enable  special  treatment  for  owner-<i>listname</i>  entries  in the
250              <a href="aliases.5.html"><b>aliases</b>(5)</a>  file,  and  don't  split  owner-<i>listname</i>  and  <i>list-</i>
251              <i>name</i>-request  address localparts when the <a href="postconf.5.html#recipient_delimiter">recipient_delimiter</a> is
252              set to "-".
253
254       <b><a href="postconf.5.html#remote_header_rewrite_domain">remote_header_rewrite_domain</a> (empty)</b>
255              Don't rewrite message headers from remote clients  at  all  when
256              this  parameter is empty; otherwise, rewrite message headers and
257              append the specified domain name to incomplete addresses.
258
259<b>SEE ALSO</b>
260       <a href="cleanup.8.html">cleanup(8)</a>, canonicalize and enqueue mail
261       <a href="postmap.1.html">postmap(1)</a>, Postfix lookup table manager
262       <a href="postconf.5.html">postconf(5)</a>, configuration parameters
263       <a href="virtual.5.html">virtual(5)</a>, virtual aliasing
264
265<b>README FILES</b>
266       <a href="DATABASE_README.html">DATABASE_README</a>, Postfix lookup table overview
267       <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, address rewriting guide
268
269<b>LICENSE</b>
270       The Secure Mailer license must be distributed with this software.
271
272<b>AUTHOR(S)</b>
273       Wietse Venema
274       IBM T.J. Watson Research
275       P.O. Box 704
276       Yorktown Heights, NY 10598, USA
277
278       Wietse Venema
279       Google, Inc.
280       111 8th Avenue
281       New York, NY 10011, USA
282
283                                                                  CANONICAL(5)
284</pre> </body> </html>
285