4.78 -> 4.80
[exim.git] / src / README.UPDATING
CommitLineData
0f4f2a88
PH
1This document contains detailed information about incompatibilities that might
2be encountered when upgrading from one release of Exim to another. The
3information is in reverse order of release numbers. Mostly these are relatively
4small points, and the configuration file is normally upwards compatible, but
5there have been two big upheavals...
6
7
8**************************************************************************
9* There was a big reworking of the way mail routing works for release *
10* 4.00. Previously used "directors" were abolished, and all routing is *
11* now done by routers. Policy controls for incoming mail are now done by *
12* Access Control Lists instead of separate options. All this means that *
13* pre-4.00 configuration files have to be massively converted. If you *
14* are coming from a 3.xx release, please read the document in the file *
15* doc/Exim4.upgrade, and allow some time to complete the upgrade. *
16* *
17* There was a big reworking of the way domain/host/net/address lists are *
18* handled at release 3.00. If you are coming from a pre-3.00 release, it *
19* might be easier to start again from a default configuration. Otherwise *
20* you need to read doc/Exim3.upgrade and do a double conversion of your *
21* configuration file. *
22**************************************************************************
23
24
25The rest of this document contains information about changes in 4.xx releases
26that might affect a running system.
2eda48c6 27
e6acf885 28
83e2f8a2 29Exim version 4.80
dec5017e
PP
30-----------------
31
83e2f8a2
PP
32 * BEWARE backwards-incompatible changes in SSL libraries, thus the version
33 bump. See points below for details.
34
dec5017e
PP
35 * The value of $tls_peerdn is now print-escaped when written to the spool file
36 in a -tls_peerdn line, and unescaped when read back in. We received reports
37 of values with embedded newlines, which caused spool file corruption.
38
39 If you have a corrupt spool file and you wish to recover the contents after
40 upgrading, then lock the message, replace the new-lines that should be part
41 of the -tls_peerdn line with the two-character sequence \n and then unlock
42 the message. No tool has been provided as we believe this is a rare
43 occurence.
44
c80c5570
PP
45 * With OpenSSL 1.0.1+, Exim now supports TLS 1.1 and TLS 1.2. If built
46 against 1.0.1a then you will get a warning message and the
47 "openssl_options" value will not parse "no_tlsv1_1": the value changes
48 incompatibly between 1.0.1a and 1.0.1b, because the value chosen for 1.0.1a
49 is infelicitous. We advise avoiding 1.0.1a.
50
51 "openssl_options" gains "no_tlsv1_1", "no_tlsv1_2" and "no_compression".
52
da3ad30d
PP
53 COMPATIBILITY WARNING: The default value of "openssl_options" is no longer
54 "+dont_insert_empty_fragments". We default to unset. That old default was
55 grandfathered in from before openssl_options became a configuration option.
56 Empty fragments are inserted by default through TLS1.0, to partially defend
57 against certain attacks; TLS1.1+ change the protocol so that this is not
58 needed. The DIEF SSL option was required for some old releases of mail
59 clients which did not gracefully handle the empty fragments, and was
60 initially set in Exim release 4.31 (see ChangeLog, item 37).
61
62 If you still have affected mail-clients, and you see SSL protocol failures
63 with this release of Exim, set:
64 openssl_options = +dont_insert_empty_fragments
65 in the main section of your Exim configuration file. You're trading off
66 security for compatibility. Exim is now defaulting to higher security and
67 rewarding more modern clients.
68
5407bfff
JH
69 * Ldap lookups returning multi-valued attributes now separate the attributes
70 with only a comma, not a comma-space sequence. Also, an actual comma within
71 a returned attribute is doubled. This makes it possible to parse the
72 attribute as a comma-separated list. Note the distinction from multiple
73 attributes being returned, where each one is a name=value pair.
c80c5570 74
9cbad13b
PP
75 * accept_8bitmime now defaults on, which is not RFC compliant but is better
76 suited to today's Internet. See http://cr.yp.to/smtp/8bitmime.html for a
77 sane rationale. Those who wish to be strictly RFC compliant, or know that
78 they need to talk to servers that are not 8-bit-clean, now need to take
79 explicit configuration action to default this option off. This is not a
80 new option, you can safely force it off before upgrading, to decouple
81 configuration changes from the binary upgrade while remaining RFC compliant.
82
17c76198
PP
83 * The GnuTLS support has been mostly rewritten, to use 2.12.x APIs. As part
84 of this, these three options are no longer supported:
85
86 gnutls_require_kx
87 gnutls_require_mac
88 gnutls_require_protocols
89
90 Their functionality is entirely subsumed into tls_require_ciphers, which is
91 no longer parsed apart by Exim but is instead given to
92 gnutls_priority_init(3), which is no longer an Exim list. See:
93
94 http://www.gnu.org/software/gnutls/manual/html_node/Priority-Strings.html
95
96 for fuller documentation of the strings parsed. The three gnutls_require_*
97 options are still parsed by Exim and, for this release, silently ignored.
98 A future release will add warnings, before a later still release removes
99 parsing entirely and the presence of the options will be a configuration
100 error.
101
83e2f8a2
PP
102 Note that by default, GnuTLS will not accept RSA-MD5 signatures in chains.
103 A tls_require_ciphers value of NORMAL:%VERIFY_ALLOW_SIGN_RSA_MD5 may
104 re-enable support, but this is not supported by the Exim maintainers.
105 Our test suite no longer includes MD5-based certificates.
106
17c76198
PP
107 This rewrite means that Exim will continue to build against GnuTLS in the
108 future, brings Exim closer to other GnuTLS applications and lets us add
109 support for SNI and other features more readily. We regret that it wasn't
110 feasible to retain the three dropped options.
111
dec5017e 112
c566dd90
PP
113Exim version 4.77
114-----------------
115
116 * GnuTLS will now attempt to use TLS 1.2 and TLS 1.1 before TLS 1.0 and SSL3,
117 if supported by your GnuTLS library. Use the existing
118 "gnutls_require_protocols" option to downgrade this if that will be a
119 problem. Prior to this release, supported values were "TLS1" and "SSL3",
120 so you should be able to update configuration prior to update.
121
39257585
PP
122 * The match_<type>{string1}{string2} expansion conditions no longer subject
123 string2 to string expansion, unless Exim was built with the new
124 "EXPAND_LISTMATCH_RHS" option. Too many people have inadvertently created
125 insecure configurations that way. If you need the functionality and turn on
126 that build option, please let the developers know, and know why, so we can
127 try to provide a safer mechanism for you.
128
a7ee5955
PP
129 The match{}{} expansion condition (for regular expressions) is NOT affected.
130 For match_<type>{s1}{s2}, all list functionality is unchanged. The only
131 change is that a '$' appearing in s2 will not trigger expansion, but instead
132 will be treated as a literal $ sign; the effect is very similar to having
133 wrapped s2 with \N...\N. If s2 contains a named list and the list definition
134 uses $expansions then those _will_ be processed as normal. It is only the
135 point at which s2 is read where expansion is inhibited.
136
137 If you are trying to test if two email addresses are equal, use eqi{s1}{s2}.
138 If you are testing if the address in s1 occurs in the list of items given
139 in s2, either use the new inlisti{s1}{s2} condition (added in 4.77) or use
140 the pre-existing forany{s2}{eqi{$item}{s1}} condition.
141
c566dd90 142
e6acf885
PP
143Exim version 4.74
144-----------------
145
4050a044
PP
146 * The integrated support for dynamically loadable lookup modules has an ABI
147 change from the modules supported by some OS vendors through an unofficial
148 patch. Don't try to mix & match.
149
150 * Some parts of the build system are now beginning to assume that the host
151 environment is POSIX. If you're building on a system where POSIX tools are
152 not the default, you might have an easier time if you switch to the POSIX
153 tools. Feel free to report non-POSIX issues as a request for a feature
154 enhancement, but if the POSIX variants are available then the fix will
155 probably just involve some coercion. See the README instructions for
156 building on such hosts.
e6acf885
PP
157
158
159Exim version 4.73
160-----------------
161
162 * The Exim run-time user can no longer be root; this was always
163 strongly discouraged, but is now prohibited both at build and
164 run-time. If you need Exim to run routinely as root, you'll need to
165 patch the source and accept the risk. Here be dragons.
166
167 * Exim will no longer accept a configuration file owned by the Exim
168 run-time user, unless that account is explicitly the value in
169 CONFIGURE_OWNER, which we discourage. Exim now checks to ensure that
a7ee5955 170 files are not writeable by other accounts.
e6acf885
PP
171
172 * The ALT_CONFIG_ROOT_ONLY build option is no longer optional and is forced
173 on; the Exim user can, by default, no longer use -C/-D and retain privilege.
174 Two new build options mitigate this.
175
176 * TRUSTED_CONFIG_LIST defines a file containing a whitelist of config
177 files that are trusted to be selected by the Exim user; one per line.
178 This is the recommended approach going forward.
179
180 * WHITELIST_D_MACROS defines a colon-separated list of macro names which
181 the Exim run-time user may safely pass without dropping privileges.
182 Because changes to this involve a recompile, this is not the recommended
183 approach but may ease transition. The values of the macros, when
43236f35 184 overridden, are constrained to match this regex: ^[A-Za-z0-9_/.-]*$
e6acf885
PP
185
186 * The system_filter_user option now defaults to the Exim run-time user,
187 rather than root. You can still set it explicitly to root and this
188 can be done with prior versions too, letting you roll versions
189 without needing to change this configuration option.
190
191 * ClamAV must be at least version 0.95 unless WITH_OLD_CLAMAV_STREAM is
192 defined at build time.
193
194
2eda48c6
TK
195Exim version 4.70
196-----------------
197
1981. Experimental Yahoo! Domainkeys support has been dropped in this release.
199It has been superceded by a native implementation of its successor DKIM.
200
2012. Up to version 4.69, Exim came with an embedded version of the PCRE library.
202As of 4.70, this is no longer the case. To compile Exim, you will need PCRE
a7ee5955 203installed. Most OS distributions have ready-made library and development
2eda48c6 204packages.
0f4f2a88
PH
205
206
3c223874
PH
207Exim version 4.68
208-----------------
209
2101. The internal implementation of the database keys that are used for ACL
211ratelimiting has been tidied up. This means that an update to 4.68 might cause
212Exim to "forget" previous rates that it had calculated, and reset them to zero.
213
214
26da7e20
PH
215Exim version 4.64
216-----------------
217
2181. Callouts were setting the name used for EHLO/HELO from $smtp_active_
219hostname. This is wrong, because it relates to the incoming message (and
220probably the interface on which it is arriving) and not to the outgoing
221callout (which could be using a different interface). This has been
222changed to use the value of the helo_data option from the smtp transport
223instead - this is what is used when a message is actually being sent. If
224there is no remote transport (possible with a router that sets up host
225addresses), $smtp_active_hostname is used. This change is mentioned here in
226case somebody is relying on the use of $smtp_active_hostname.
227
ebc9d865
PH
2282. A bug has been fixed that might just possibly be something that is relied on
229in some configurations. In expansion items such as ${if >{xxx}{yyy}...} an
230empty string (that is {}) was being interpreted as if it was {0} and therefore
231treated as the number zero. From release 4.64, such strings cause an error
232because a decimal number, possibly followed by K or M, is required (as has
233always been documented).
234
b6c27e28
PH
2353. There has been a change to the GnuTLS support (ChangeLog/PH/20) to improve
236Exim's performance. Unfortunately, this has the side effect of being slightly
237non-upwards compatible for versions 4.50 and earlier. If you are upgrading from
238one of these earlier versions and you use GnuTLS, you must remove the file
239called gnutls-params in Exim's spool directory. If you don't do this, you will
240see this error:
241
242 TLS error on connection from ... (DH params import): Base64 decoding error.
243
244Removing the file causes Exim to recompute the relevant encryption parameters
245and cache them in the new format that was introduced for release 4.51 (May
2462005). If you are upgrading from release 4.51 or later, there should be no
247problem.
248
26da7e20 249
a5bd321b
PH
250Exim version 4.63
251-----------------
252
253When an SMTP error message is specified in a "message" modifier in an ACL, or
254in a :fail: or :defer: message in a redirect router, Exim now checks the start
255of the message for an SMTP error code. This consists of three digits followed
256by a space, optionally followed by an extended code of the form n.n.n, also
257followed by a space. If this is the case and the very first digit is the same
258as the default error code, the code from the message is used instead. If the
259very first digit is incorrect, a panic error is logged, and the default code is
260used. This is an incompatible change, but it is not expected to affect many (if
261any) configurations. It is possible to suppress the use of the supplied code in
262a redirect router by setting the smtp_error_code option false. In this case,
263any SMTP code is quietly ignored.
264
265
47ca6d6c
PH
266Exim version 4.61
267-----------------
268
8def5aaf
PH
2691. The default number of ACL variables of each type has been increased to 20,
270and it's possible to compile Exim with more. You can safely upgrade to this
271release if you already have messages on the queue with saved ACL variable
272values. However, if you downgrade from this release with messages on the queue,
273any saved ACL values they may have will be lost.
274
2752. The default value for rfc1413_query_timeout has been changed from 30s to 5s.
47ca6d6c
PH
276
277
8857ccfd
PH
278Exim version 4.54
279-----------------
280
281There was a problem with 4.52/TF/02 in that a "name=" option on control=
282submission terminated at the next slash, thereby not allowing for slashes in
283the name. This has been changed so that "name=" takes the rest of the string as
284its data. It must therefore be the last option.
285
286
f3f0a1f0
PH
287Version 4.53
288------------
289
290If you are using the experimental Domain Keys support, you must upgrade to
291at least libdomainkeys 0.67 in order to run this release of Exim.
292
293
b5aea5e1
PH
294Version 4.51
295------------
296
c688b954
PH
2971. The format in which GnuTLS parameters are cached (in the file gnutls-params
298in the spool directory) has been changed. The new format can also be generated
b5aea5e1
PH
299externally, so it is now possible to update the values from outside Exim. This
300has been implemented in an upwards, BUT NOT downwards, compatible manner.
301Upgrading should be seamless: when Exim finds that it cannot understand an
302existing cache file, it generates new parameters and writes them to the cache
303in the new format. If, however, you downgrade from 4.51 to a previous release,
304you MUST delete the gnutls-params file in the spool directory, because the
305older Exim will not recognize the new format.
306
c688b954
PH
3072. When doing a callout as part of verifying an address, Exim was not paying
308attention to any local part prefix or suffix that was matched by the router
309that accepted the address. It now behaves in the same way as it does for
310delivery: the affixes are removed from the local part unless
311rcpt_include_affixes is set on the transport. If you have a configuration that
312uses prefixes or suffixes on addresses that could be used for callouts, and you
313want the affixes to be retained, you must make sure that rcpt_include_affixes
314is set on the transport.
315
447d236c
PH
3163. Bounce and delay warning messages no longer contain details of delivery
317errors, except for explicit messages (e.g. generated by :fail:) and SMTP
318responses from remote hosts.
319
b5aea5e1 320
8b5af54d
PH
321Version 4.50
322------------
323
4964e932
PH
324The exicyclog script has been updated to use three-digit numbers in rotated log
325files if the maximum number to keep is greater than 99. If you are already
326keeping more than 99, there will be an incompatible change when you upgrade.
327You will probably want to rename your old log files to the new form before
c3af992c 328running the new exicyclog.
8b5af54d
PH
329
330
0f4f2a88
PH
331Version 4.42
332------------
333
334RFC 3848 specifies standard names for the "with" phrase in Received: header
335lines when AUTH and/or TLS are in use. This is the "received protocol"
336field. Exim used to use "asmtp" for authenticated SMTP, without any
337indication (in the protocol name) for TLS use. Now it follows the RFC and
338uses "esmtpa" if the connection is authenticated, "esmtps" if it is
339encrypted, and "esmtpsa" if it is both encrypted and authenticated. These names
340appear in log lines as well as in Received: header lines.
341
342
343Version 4.34
344------------
345
346Change 4.31/2 gave problems to data ACLs and local_scan() functions that
347expected to see a Received: header. I have changed to yet another scheme. The
348Received: header is now generated after the body is received, but before the
349ACL or local_scan() is called. After they have run, the timestamp in the
350Received: header is updated.
351
352Thus, change (a) of 4.31/2 has been reversed, but change (b) is still true,
353which is lucky, since I decided it was a bug fix.
354
355
356Version 4.33
357------------
358
359If an expansion in a condition on a "warn" statement fails because a lookup
360defers, the "warn" statement is abandoned, and the next ACL statement is
361processed. Previously this caused the whole ACL to be aborted.
362
363
364Version 4.32
365------------
366
367Change 4.31/2 has been reversed, as it proved contentious. Recipient callout
368verification now uses <> in the MAIL command by default, as it did before. A
369new callout option, "use_sender", has been added to request the other
370behaviour.
371
372
373Version 4.31
374------------
375
3761. If you compile Exim to use GnuTLS, it now requires the use of release 1.0.0
377 or greater. The interface to the obsolete 0.8.x releases is no longer
378 supported. There is one externally visible change: the format for the
379 display of Distinguished Names now uses commas as a separator rather than a
380 slash. This is to comply with RFC 2253.
381
3822. When a message is received, the Received: header line is now generated when
383 reception is complete, instead of at the start of reception. For messages
384 that take a long time to come in, this changes the meaning of the timestamp.
385 There are several side-effects of this change:
386
387 (a) If a message is rejected by a DATA or non-SMTP ACL, or by local_scan(),
388 the logged header lines no longer include the local Received: line,
389 because it has not yet been created. If the message is a non-SMTP one,
390 and the error is processed by sending a message to the sender, the copy
391 of the original message that is returned does not have an added
392 Received: line.
393
394 (b) When a filter file is tested using -bf, no additional Received: header
395 is added to the test message. After some thought, I decided that this
396 is a bug fix.
397
398 The contents of $received_for are not affected by this change. This
399 variable still contains the single recipient of a message, copied after
400 addresses have been rewritten, but before local_scan() is run.
401
4022. Recipient callout verification, like sender verification, was using <> in
403 the MAIL FROM command. This isn't really the right thing, since the actual
404 sender may affect whether the remote host accepts the recipient or not. I
405 have changed it to use the actual sender in the callout; this means that
406 the cache record is now keyed on a recipient/sender pair, not just the
407 recipient address. There doesn't seem to be a real danger of callout loops,
408 since a callout by the remote host to check the sender would use <>.
409
410
411Version 4.30
412------------
413
4141. I have abolished timeout_DNS as an error that can be detected in retry
415 rules, because it has never worked. Despite the fact that it has been
416 documented since at least release 1.62, there was no code to support it.
417 If you have used it in your retry rules, you will now get a warning message
418 to the log and panic log. It is now treated as plain "timeout".
419
4202. After discussion on the mailing list, Exim no longer adds From:, Date:, or
421 Message-Id: header lines to messages that do not originate locally, that is,
422 messages that have an associated sending host address.
423
4243. When looking up a host name from an IP address, Exim now tries the DNS
425 first, and only if that fails does it use gethostbyaddr() (or equivalent).
426 This change was made because on some OS, not all the names are given for
427 addresses with multiple PTR records via the gethostbyaddr() interface. The
428 order of lookup can be changed by setting host_lookup_order.
429
430
431Version 4.23
432------------
433
4341. The new FIXED_NEVER_USERS build-time option creates a list of "never users"
435 that cannot be overridden. The default in the distributed EDITME is "root".
436 If for some reason you were (against advice) running deliveries as root, you
437 will have to ensure that FIXED_NEVER_USERS is not set in your
438 Local/Makefile.
439
4402. The ${quote: operator now quotes an empty string, which it did not before.
441
4423. Version 4.23 saves the contents of the ACL variables with the message, so
443 that they can be used later. If one of these variables contains a newline,
444 there will be a newline character in the spool that will not be interpreted
445 correctely by a previous version of Exim. (Exim ignores keyed spool file
446 items that it doesn't understand - precisely for this kind of problem - but
447 it expects them all to be on one line.)
448
449 So the bottom line is: if you have newlines in your ACL variables, you
450 cannot retreat from 4.23.
451
452
453Version 4.21
454------------
455
4561. The idea of the "warn" ACL verb is that it adds a header or writes to the
457 log only when "message" or "log_message" are set. However, if one of the
458 conditions was an address verification, or a call to a nested ACL, the
459 messages generated by the underlying test were being passed through. This
460 no longer happens. The underlying message is available in $acl_verify_
461 message for both "message" and "log_message" expansions, so it can be
462 passed through if needed.
463
4642. The way that the $h_ (and $header_) expansions work has been changed by the
465 addition of RFC 2047 decoding. See the main documentation (the NewStuff file
466 until release 4.30, then the manual) for full details. Briefly, there are
467 now three forms:
468
469 $rh_xxx: and $rheader_xxx: give the original content of the header
470 line(s), with no processing at all.
471
472 $bh_xxx: and $bheader_xxx: remove leading and trailing white space, and
473 then decode base64 or quoted-printable "words" within the header text,
474 but do not do charset translation.
475
476 $h_xxx: and $header_xxx: attempt to translate the $bh_ string to a
477 standard character set.
478
479 If you have previously been using $h_ expansions to access the raw
480 characters, you should change to $rh_ instead.
481
4823. When Exim creates an RFC 2047 encoded word in a header line, it labels it
483 with the default character set from the headers_charset option instead of
484 always using iso-8859-1.
485
4864. If TMPDIR is defined in Local/Makefile (default in src/EDITME is
487 TMPDIR="/tmp"), Exim checks for the presence of an environment variable
488 called TMPDIR, and if it finds it is different, it changes its value.
489
4905. Following a discussion on the list, the rules by which Exim recognises line
491 endings on incoming messages have been changed. The -dropcr and drop_cr
492 options are now no-ops, retained only for backwards compatibility. The
493 following line terminators are recognized: LF CRLF CR. However, special
494 processing applies to CR:
495
496 (i) The sequence CR . CR does *not* terminate an incoming SMTP message,
497 nor a local message in the state where . is a terminator.
498
499 (ii) If a bare CR is encountered in a header line, an extra space is added
500 after the line terminator so as not to end the header. The reasoning
501 behind this is that bare CRs in header lines are most likely either
502 to be mistakes, or people trying to play silly games.
503
5046. The code for using daemon_smtp_port, local_interfaces, and the -oX options
505 has been reorganized. It is supposed to be backwards compatible, but it is
506 mentioned here just in case I've screwed up.
507
508
509
510Version 4.20
511------------
512
5131. I have tidied and re-organized the code that uses alarm() for imposing time
514 limits on various things. It shouldn't affect anything, but if you notice
515 processes getting stuck, it may be that I've broken something.
516
5172. The "arguments" log selector now also logs the current working directory
518 when Exim is called.
519
5203. An incompatible change has been made to the appendfile transport. This
521 affects the case when it is used for file deliveries that are set up by
522 .forward and filter files. Previously, any settings of the "file" or
523 "directory" options were ignored. It is hoped that, like the address_file
524 transport in the default configuration, these options were never in fact set
525 on such transports, because they were of no use.
526
527 Now, if either of these options is set, it is used. The path that is passed
528 by the router is in $address_file (this is not new), so it can be used as
529 part of a longer path, or modified in any other way that expansion permits.
530
531 If neither "file" nor "directory" is set, the behaviour is unchanged.
532
5334. Related to the above: in a filter, if a "save" command specifies a non-
534 absolute path, the value of $home/ is pre-pended. This no longer happens if
535 $home is unset or is set to an empty string.
536
5375. Multiple file deliveries from a filter or .forward file can never be
538 batched; the value of batch_max on the transport is ignored for file
539 deliveries. I'm assuming that nobody ever actually set batch_max on the
540 address_file transport - it would have had odd effects previously.
541
5426. DESTDIR is the more common variable that ROOT for use when installing
543 software under a different root filing system. The Exim install script now
544 recognizes DESTDIR first; if it is not set, ROOT is used.
545
5467. If DESTDIR is set when installing Exim, it no longer prepends its value to
547 the path of the system aliases file that appears in the default
548 configuration (when a default configuration is installed). If an aliases
549 file is actually created, its name *does* use the prefix.
550
551
552Version 4.14
553------------
554
5551. The default for the maximum number of unknown SMTP commands that Exim will
556accept before dropping a connection has been reduced from 5 to 3. However, you
557can now change the value by setting smtp_max_unknown_commands.
558
5592. The ${quote: operator has been changed so that it turns newline and carriage
560return characters into \n and \r, respectively.
561
5623. The file names used for maildir messages now include the microsecond time
563fraction as well as the time in seconds, to cope with systems where the process
564id can be re-used within the same second. The format is now
565
566 <time>.H<microsec>P<pid>.<host>
567
568This should be a compatible change, but is noted here just in case.
569
5704. The rules for creating message ids have changed, to cope with systems where
571the process id can be re-used within the same second. The format, however, is
572unchanged, so this should not cause any problems, except as noted in the next
573item.
574
5755. The maximum value for localhost_number has been reduced from 255 to 16, in
576order to implement the new message id rules. For operating systems that have
577case-insensitive file systems (Cygwin and Darwin), the limit is 10.
578
5796. verify = header_syntax was allowing unqualified addresses in all cases. Now
580it allows them only for locally generated messages and from hosts that match
581sender_unqualified_hosts or recipient_unqualified_hosts, respectively.
582
5837. For reasons lost in the mists of time, when a pipe transport was run, the
584environment variable MESSAGE_ID was set to the message ID preceded by 'E' (the
585form used in Message-ID: header lines). The 'E' has been removed.
586
587
588Version 4.11
589------------
590
5911. The handling of lines in the configuration file has changed. Previously,
592macro expansion was applied to logical lines, after continuations had been
593joined on. This meant that it could not be used in .include lines, which are
594handled as physical rather than logical lines. Macro expansion is now done on
595physical lines rather than logical lines. This means there are two
596incompatibilities:
597
598 (a) A macro that expands to # to turn a line into a comment now applies only
599 to the physical line where it appears. Previously, it would have caused
600 any following continuations also to be ignored.
601
602 (b) A macro name can no longer be split over the boundary between a line and
603 its continuation. Actually, this is more of a bug fix. :-)
604
6052. The -D command line option must now all be within one command line item.
606This makes it possible to use -D to set a macro to the empty string by commands
607such as
608
609 exim -DABC ...
610 exim -DABC= ...
611
612Previously, these items would have moved on to the next item on the command
613line. To include spaces in a macro definition item, quotes must be used, in
614which case you can also have spaces after -D and surrounding the equals. For
615example:
616
617 exim '-D ABC = something' ...
618
6193. The way that addresses that redirect to themselves are handled has been
620changed, in order to fix an obscure bug. This should not cause any problems
621except in the case of wanting to go back from a 4.11 (or later) release to an
622earlier release. If there are undelivered messages on the spool that contain
623addresses which redirect to themselves, and the redirected addresses have
624already been delivered, you might get a duplicate delivery if you revert to an
625earlier Exim.
626
6274. The default way of looking up IP addresses for hosts in the manualroute and
628queryprogram routers has been changed. If "byname" or "bydns" is explicitly
629specified, there is no change, but if no method is specified, Exim now behaves
630as follows:
631
632 First, a DNS lookup is done. If this yields anything other than
633 HOST_NOT_FOUND, that result is used. Otherwise, Exim goes on to try a call to
634 getipnodebyname() (or gethostbyname() on older systems) and the result of the
635 lookup is the result of that call.
636
637This change has been made because it has been discovered that on some systems,
638if a DNS lookup called via getipnodebyname() times out, HOST_NOT_FOUND is
639returned instead of TRY_AGAIN. Thus, it is safest to try a DNS lookup directly
640first, and only if that gives a definite "no such host" to try the local
641function.
642
6435. In fixing the minor security problem with pid_file_path, I have removed some
644backwards-compatible (undocumented) code which was present to ease conversion
645from Exim 3. In Exim 4, pid_file_path is a literal; in Exim 3 it was allowed to
646contain "%s", which was replaced by the port number for daemons listening on
647non-standard ports. In Exim 4, such daemons do not write a pid file. The
648backwards compatibility feature was to replace "%s" by nothing if it occurred
649in an Exim 4 setting of pid_file_path. The bug was in this code. I have solved
650the problem by removing the backwards compatibility feature. Thus, if you still
651have "%s" somewhere in a setting of pid_file_path, you should remove it.
652
6536. There has been an extension to lsearch files. The keys in these files may
654now be quoted in order to allow for whitespace and colons in them. This means
655that if you were previously using keys that began with a doublequote, you will
656now have to wrap them with extra quotes and escape the internal quotes. The
657possibility that anybody is actually doing this seems extremely remote, but it
658is documented just in case.
659
660
661Version 4.10
662------------
663
664The build-time parameter EXIWHAT_KILL_ARG has been renamed EXIWHAT_KILL_SIGNAL
665to better reflect its function. The OS-specific files have been updated. Only
666if you have explicitly set this in your Makefile (highly unlikely) do you need
667to change anything.
668
669****