1 files changed, 102 insertions, 55 deletions
diff --git a/proto/ADDRESS_REWRITING_README.html b/proto/ADDRESS_REWRITING_README.html
index c858410..631a7d3 100644
--- a/proto/ADDRESS_REWRITING_README.html
+++ b/proto/ADDRESS_REWRITING_README.html
@@ -94,9 +94,7 @@ as invalid </a>
 
 <ul>
 
-<li> <a href="#resolve"> Resolve address to destination </a>
-
-<li> <a href="#transport"> Mail transport switch </a>
+<li> <a href="#resolve"> Resolve address to (transport, next-hop destination) </a>
 
 <li> <a href="#relocated"> Relocated users table </a>
 
@@ -312,8 +310,8 @@ find what you need.  </p>
 <table border="1">
 
 <tr> <th nowrap> Address manipulation </th> <th nowrap> Scope </th>
-<th> Daemon </th> <th nowrap> Global turn-on control </th> <th nowrap> Selective
-turn-off control </th> </tr>
+<th> Daemon </th> <th nowrap> Turn-on controls </th> <th nowrap> 
+Turn-off controls </th> </tr>
 
 <tr> <td> <a href="#standard"> Rewrite addresses to standard form</a>
 </td> <td nowrap> all mail </td> <td> trivial-<br>rewrite(8) </td>
@@ -340,13 +338,12 @@ sender_bcc_maps, recipient_bcc_maps </td> <td> receive_override_options
 nowrap> all mail </td> <td> cleanup(8) </td> <td> virtual_alias_maps
 </td> <td> receive_override_options </td> </tr>
 
-<tr> <td> <a href="#resolve"> Resolve address to destination </a>
-</td> <td nowrap> all mail </td> <td> trivial-<br>rewrite(8) </td>
-<td> none </td> <td> none </td> </tr>
-
-<tr> <td> <a href="#transport"> Mail transport switch</a> </td>
-<td nowrap> all mail </td> <td> trivial-<br>rewrite(8) </td> <td>
-transport_maps </td> <td> none </td> </tr>
+<tr> <td> <a href="#resolve"> Resolve address to (transport, next-hop
+destination) </a> </td> <td nowrap> all mail </td> <td>
+trivial-<br>rewrite(8) </td> <td> local_transport, virtual_transport,
+relay_transport, default_transport, relayhost,
+sender_dependent_relayhost_maps, sender_dependent_default_transport_maps
+</td> <td> content_filter </td> </tr>
 
 <tr> <td> <a href="#relocated"> Relocated users table</a> </td>
 <td nowrap> all mail </td> <td> trivial-<br>rewrite(8) </td> <td>
@@ -774,6 +771,11 @@ may be a more appropriate vehicle. See the VIRTUAL_README document
 for an overview of methods to host virtual domains with Postfix.
 </p>
 
+<p> Note: virtual aliasing (virtual_alias_maps) applies to all
+recipients: local(8), virtual, and remote.  <!-- wrap filler -->
+This is unlike local aliasing (alias_maps) which applies only to
+local(8) recipients. </p>
+
 <p> Virtual aliasing is disabled by default. To enable, edit the
 virtual_alias_maps parameter in the main.cf file and
 specify one or more lookup tables, separated by whitespace or
@@ -833,9 +835,8 @@ trivial-rewrite(8) server. </p>
 
 <ul>
 
-<li> <a href="#resolve"> Resolve address to destination </a>
-
-<li> <a href="#transport"> Mail transport switch</a>
+<li> <a href="#resolve"> Resolve address to (transport, next-hop
+destination) </a>
 
 <li> <a href="#relocated"> Relocated users table</a>
 
@@ -873,67 +874,108 @@ via the local(8) delivery agent: </p>
 step in more detail, with specific examples or with pointers to
 documentation with examples. </p>
 
-<h3> <a name="resolve"> Resolve address to destination </a> </h3>
+<h3> <a name="resolve"> Resolve address to (transport, next-hop
+destination) </a> </h3>
 
 <p> The Postfix qmgr(8) queue manager selects new mail from the
-incoming queue or old mail from the deferred queue, and asks the
-trivial-rewrite(8) address rewriting and resolving daemon where it
-should be delivered. </p>
+incoming queue or old mail from the deferred queue. First it
+looks for overrides: </p>
+
+<ul>
 
-<p> As of version 2.0, Postfix distinguishes four major address
-classes. Each class has its own list of domain names, and each
-class has its own default delivery method, as shown in the table
-below.  See the ADDRESS_CLASS_README document for the fine details.
-Postfix versions before 2.0 only distinguish between local delivery
-and everything else.  </p>
+<li> <p> The REDIRECT action in access(5), header_checks(5) or
+body_checks(5) overrides all recipients of the message, and overrides
+a content_filter setting, and FILTER action in access(5),
+header_checks(5) or body_checks(5). The REDIRECT action was implemented
+as a short-cut to retaliate for abuse. </p>
+
+<li> <p> A content_filter setting and FILTER action in access(5),
+header_checks(5) or body_checks(5) provide their own (transport,
+next-hop destination) information. This bypasses all the steps that
+are described in the remainder of this section. </p>
+
+</ul>
+
+<p> When there is no content filter override, the qmgr(8) queue
+manager asks the trivial-rewrite(8) address rewriting and resolving
+daemon for each recipient how to deliver it (which message delivery
+transport) and where to deliver it (what next-hop destination). </p>
+
+<p> As of version 2.0, Postfix distinguishes four major domain
+classes. Each class has its own list of recipient domain names, and
+each class has its own delivery method, as shown in the table below.
+See the ADDRESS_CLASS_README document for the fine details.  Postfix
+versions before 2.0 only distinguish between local delivery and
+everything else. </p>
+
+<p> Note that the table does not match recipients against
+virtual_alias_domains. The reason is that all valid recipients in
+a virtual alias domain must be aliased to an address in a different
+domain. All other recipients in a virtual alias domain are by
+definition undeliverable, and do not need to be considered here.
+</p>
 
 <blockquote>
 
 <table border="1">
 
-<tr><th align="left">Destination domain list </th> <th
-align="left">Default delivery method </th> <th>Availability
-</th> </tr>
+<tr> <th align="left">Domain class</th> <th align="left">Recipient
+domain match </th> <th> Delivery method </th> <th>Availability </th>
+</tr>
 
-<tr><td>$mydestination, $inet_interfaces, $proxy_interfaces </td>
-<td>$local_transport </td> <td>Postfix 1.0</td></tr>
+<tr><td>Local</td> <td>mydestination, inet_interfaces, proxy_interfaces
+</td> <td>local_transport </td> <td>Postfix 1.0</td></tr>
 
-<tr><td>$virtual_mailbox_domains </td> <td>$virtual_transport </td>
-<td>Postfix 2.0</td> </tr>
+<tr><td>Virtual mailbox</td> <td>virtual_mailbox_domains </td>
+<td>virtual_transport </td> <td>Postfix 2.0</td> </tr>
 
-<tr><td>$relay_domains </td> <td>$relay_transport </td> <td>Postfix
-2.0</td> </tr>
+<tr><td>Relay</td> <td>relay_domains </td> <td>relay_transport
+</td> <td>Postfix 2.0</td> </tr>
 
-<tr><td>none </td> <td>$default_transport </td> <td>Postfix 1.0</td>
-</tr>
+<tr><td>Default</td><td> none </td> <td>default_transport </td>
+<td>Postfix 1.0</td> </tr>
 
 </table>
 
 </blockquote>
 
-<h3> <a name="transport"> Mail transport switch </a> </h3>
+<p> The delivery methods in the above table may include a next-hop
+destination in addition to a delivery transport. This may override
+the next-hop destination that is by default taken from the recipient
+domain. </p>
 
-<p> Once the trivial-rewrite(8) daemon has determined a default
-delivery method it searches the optional transport(5) table for
-information that overrides the message destination and/or delivery
-method.  Typical use of the transport(5) table is to send mail to
-a system
-that is not connected to the Internet, or to use a special SMTP
-client configuration for destinations that have special requirements.
-See, for example, the STANDARD_CONFIGURATION_README and UUCP_README
-documents, and the examples in the transport(5) manual page.  </p>
+<p> Over time, features have been added to override the above
+transport and/or next-hop destination information. The following
+table lists where a transport or next-hop destination may be taken
+from, depending on the recipient domain class. </p>
 
-<p> Transport table lookups are disabled by default. To enable,
-edit the transport_maps parameter in the main.cf file and specify
-one or more lookup tables, separated by whitespace or commas. </p>
+<blockquote>
 
-<p> Example: </p>
+<table border="1">
+
+<tr> <th>Domain class</th> <th>Transport sources (in order of
+descending precedence)</th> <th> Next hop sources (in order of
+descending precedence)</th> </tr>
+
+<tr> <td> Local </td> <td> transport_maps, local_transport</td>
+<td> transport_maps, local_transport, recipient domain</td> </tr>
+
+<tr> <td> Virtual mailbox </td> <td> transport_maps,
+virtual_transport</td> <td> transport_maps, virtual_transport,
+recipient domain</td> </tr>
+
+<tr> <td> Relay </td> <td> transport_maps, relay_transport</td>
+<td> transport_maps, relay_transport, sender_dependent_relayhost_maps,
+relayhost, recipient domain</td> </tr>
+
+<tr> <td> Default </td> <td> transport_maps,
+sender_dependent_default_transport_maps, default_transport</td>
+<td> transport_maps, sender_dependent_default_transport_maps,
+default_transport, sender_dependent_relayhost_maps, relayhost,
+recipient domain</td> </tr>
+
+</table>
 
-<blockquote>
-<pre>
-/etc/postfix/main.cf:
-    transport_maps = hash:/etc/postfix/transport
-</pre>
 </blockquote>
 
 <h3> <a name="relocated"> Relocated users table </a> </h3>
@@ -1019,6 +1061,11 @@ direct mail for standard aliases such as postmaster to real people.
 The table can also be used to map "Firstname.Lastname" addresses
 to login names. </p>
 
+<p> Note: local aliasing (alias_maps) applies only to local(8)
+recipients. This is  unlike virtual aliasing (virtual_alias_maps)
+which applies to all recipients: local(8), virtual, and remote.
+</p>
+
 <p> Alias lookups are enabled by default. The default configuration
 depends on the operating system environment, but it is typically
 one of the following: </p>