Release v2.4.0

* Change configuration syntax to match new Dovecot configuration syntax.
* vacation: Reduce default days to 60 from infinity
* vacation: vacation_max_period=0 is now an error.
* Version has been changed to match Dovecot version.
+ Added i;unicode-casecmp comparator.
- Lots of bugs have been fixed.

Release v0.5.21.1

- sieve: When saving to local storage failed after a successful action
  in sieve (e.g. redirect, vacation), the mail was reported as
  successfully delivered, although it was lost locally.

Release v0.5.21

- sieve: Using the deleteheader action on a message with a broken/invalid
  header can cause the Sieve interpreter to crash with an assert panic.
  This can happen e.g. when the message is missing the empty EOH line
  between the headers and the body of the message. Fixes:
  Panic: file edit-mail.c: line 820 (edit_mail_headers_parse):
  assertion failed: (body_offset > 0).
- sieve: Pigeonhole added an extra Message-ID header during mail
  forwarding when the existing one was invalid. Now it adds the
  Message-ID only if it is entirely missing. Existing Message-ID(s) are
  left unchanged.

Release v0.5.20

* No changes - release done to keep version numbers synced.

Release v0.5.19

* No updates

Release v0.5.18

- duplicate: Users without a home directory can crash with Sieve when
  using duplicate database. v2.3.17 regression.
- imapsieve: When mail was expunged when processing imapsieve events, a
  crash could occur. Fixes Panic: file mail-index-map.c:
  line 558 (mail_index_map_lookup_seq_range): assertion failed: (first_uid > 0)
- managesieve-login: Proxy didn't support forwarding the forward_* passdb fields.
- redirect: Sieve would crash if redirect after keep-equivalent action failed.
- sieve: Interpreter crashes when the Sieve index extension is used with
  index zero.
- vnd.dovecot.filter: Envelope sender string may become corrupted when
  Sieve scripts are using vnd.dovecot.filter. This could end up
  corrupting mbox's From line and return wrong envelope sender string in

Release v0.5.17.1

- managesieve: Dovecot failed to start if ssl_ca was too large.
- lib-sieve-tool: Binaries failed to run if ssl_ca was too large.

Release v0.5.17

- duplicate: The Sieve duplicate test is prone to false negatives when
  the user receives many e-mails concurrently, meaning that duplicate
  deliveries can still occur.
- fileinto: v2.3.16 regression: Sieve delivery crashes if mail is
  delivered to non-existing and existing folder.
- imap-filter-sieve: v2.3.15 regression: The CPU limits on Sieve
  execution are too easily exceeded in IMAP context (the IMAPSieve and
  FILTER=SIEVE capabilities). Changed the default to unlimited CPU time
  for IMAP context, since similar excessive resource usage can be caused
  by other means as well. The CPU limits on Sieve scripts executed at
  LDA/LMTP delivery are still enforced by default.
- redirect:  The Sieve redirect action has protections against users
  triggering mail loops. Unfortunately, the detection of a redirect mail
  loop sometimes causes the message to get lost if no other Sieve action
  is applied that delivers the message somewhere else.
- redirect: v2.3.16 regression: With certain Sieve scripts if redirect
  fails due to temporary failure, the lmtp process may crash after the
  delivery. Fixes:
  Panic: file mail-user.c: line 229 (mail_user_deinit):
  assertion failed: ((*user)->refcount == 1).

Released 0.5.16

 * .dovecot.sieve.log file now includes year in the header.
 * Change Sieve script result execution to delay definitive action
   execution to the end of a successful Sieve script execution session.
   This is part of an effort to solve problems with the Sieve duplicate
   test. As a side-effect, some rare temporary-error cases yield
   different results, in which partial failure is more likely.

Release v0.5.15

 * CVE-2020-28200: Sieve interpreter is not protected against abusive
   scripts that claim excessive resource usage. Fixed by limiting the
   user CPU time per single script execution and cumulatively over
   several script runs within a configurable timeout period. Sufficiently
   large CPU time usage is summed in the Sieve script binary and execution
   is blocked when the sum exceeds the limit within that time. The block
   is lifted when the script is updated after the resource usage times out.
 * Disconnection log messages are now more standardized across services.
   They also always now start with "Disconnected" prefix.
 - managesieve: Commands pipelined together with and just after the
   authenticate command cause these commands to be executed twice.