-$Cambridge: exim/doc/doc-misc/WishList,v 1.64 2006/03/08 09:43:10 ph10 Exp $
-
EXIM 4 WISH LIST
----------------
+This Wish List is now obsolete. The items it contains have been imported into
+the Exim Bugzilla, which is where all new wishes should be added. This file is
+no longer maintained. Some day it should be deleted.
+
+
+===============================================================================
Even when it was first released, Exim 4 had a Wish List because not all the
things suggested for it were implemented. The list has not stopped growing...
So several warnings could be generated as the mailbox got bigger and bigger.
------------------------------------------------------------------------------
-(146) 15-May-2000 M Allow SMTP error codes in retry rules
-
-This would allow special handling of certain errors from certain hosts. In
-particular, it would allow failing of certain 4xx codes.
-
-This is now available for 4xx responses to RCPT commands. Is anything more
-needed? Apparently, yes; there's been a request for a similar feature for MAIL
-commands.
-------------------------------------------------------------------------------
-
(148) 15-May-2000 S Warn recipient if message rejected for quota excession.
Heinz Ekker
that it can be used as a safety-net while testing configurations. Instead of a
local bounce, the message stays on the queue; instead of 5xx SMTP responses,
4xx ones are given.
-
-The ability to do the opposite - turn 4xx into 5xx under certain circumstances
-might also be useful (e.g. after a certain time). This might best be done by
-extending the retry logic to recognize 4xx as a special error. (This is now
-done.)
------------------------------------------------------------------------------
(202) 10-Oct-03 S -bvsomething to do a callout after the verify
------------------------------------------------------------------------------
(209) 31-Oct-03 S a way of making crashes in pipe commands temporary errors
-
------------------------------------------------------------------------------
(210) 31-Oct-03 S runtime option to change the daemon name used for tcprwappers
changed.)
------------------------------------------------------------------------------
-(216) 27-Nov-03 S Option to bounce if required TLS doesn't happen
-
-This is for the smtp transport with hosts_require_tls set. Currently, it
-defers. Possibly the best approach is to make the error one that can be seen by
-the retry logic.
-------------------------------------------------------------------------------
-
(217) 27-Nov-03 M A function to pass back variables from Perl
This is a function that can be called from Perl, to take a name and a value and
both of them.
------------------------------------------------------------------------------
-(286) 21-Jul-04 M Distinguishing a larger number of errors
-
-For instance, detecting "connection reset by peer" (ENETRESET or ECONNRESET)
-might be useful.
-------------------------------------------------------------------------------
-
(288) 10-Aug-04 M Option for verify to require MX
e.g. verify=sender/require_mx
enwildlsearch.
------------------------------------------------------------------------------
-(350) 28-Feb-06 S Additional errors for retry rules
+(351) 31-Mar-06 ? Allow some/all/a few internal variables to be set
+
+The original idea was to allow "set authenticated = x" to pretend a connection
+is authenticated after other conditions are true. This can, of course, be
+packaged up using macros in other ways. Setting other variables could cause
+problems.
+------------------------------------------------------------------------------
+
+(352) 04-Apr-06 S Add +accept_defer for host lists (and maybe others)
+
+At present, a defer causes a delivery defer. For non-critical ACLs there are
+times when it may be better to accept. See also 226 and 289.
+------------------------------------------------------------------------------
+
+(354) 30-Jun-06 ? Extensions to SMTP error codes
+
+A number of ideas arose following a discussion on the mailing list. I record
+them here so that they don't get lost. The motivations were to support the 551
+bounce code and enhanced status codes. Suggestions are to add a new ACL
+feature, possibly one of:
+
+ errorcode = 511
+ control = errorcode=551
+ message = 551 xxxx
+
+where in the last case, it's recognized by being 3 digits. In all cases, the
+first digit must be "right" for the circumstance - ignore or fault if not?
+
+To handle ESC, perhaps a new variable called $smtp_errorcode, settable by an
+option in a router when it fails, would do the trick. It could be used in any
+of the above modifiers.
+------------------------------------------------------------------------------
+
+(355) 30-Jun-06 ? Facility to permit experiments with SMTP extensions
+
+This is what was suggested:
+
+- adding some expansion variables: $ehlo_extensions (which will
+ hold the remote server supported smtp extensions announced
+ in the ehlo) and $rcpt_arguments with any RCPT extra argument
+
+- a main configuration option for adding ehlo extensions to the
+ ehlo response, like:
+
+ extra_ehlo_extensions = XFOO : XBAR
+
+- a extra option for the smtp transport to add arguments to
+ the RCPT TO command, like:
+
+ rcpt_args = FOO=BAR (will make exim issue RCPT TO:<a@b.c> FOO=BAR
+ when delivering that message)
+
+- a new acl for unknown smtp commands
-(i) Unexpected connection close; (ii) mail_4xx.
+This should be very simple to implement and will allow to make
+some experiments and implement custom extensions, i.e. one to
+known if remote client will redirect on 551 or not. Also the acl
+for unknown smpt command could be used for other purposes, like
+to dectect and react to some kiddies that send things like
+http://... on the smtp port.
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---- HWM 350 ------------------------------------------------------------------
+--- HWM 355 ------------------------------------------------------------------
---------------------------- End of WishList ---------------------------------