v2.3.13 2021-01-04	Aki Tuomi <aki.tuomi@open-xchange.com>

	* CVE-2020-24386: Specially crafted command can cause IMAP hibernate to
	  allow logged in user to access other people's emails and filesystem
	  information.
	* Metric filter and global event filter variable syntax changed to a
	  SQL-like format. See https://doc.dovecot.org/configuration_manual/event_filter/
	* auth: Added new aliases for %{variables}. Usage of the old ones is
	  possible, but discouraged.
	* auth: Removed RPA auth mechanism, SKEY auth mechanism, NTLM auth
	  mechanism and related password schemes.
	* auth: Removed passdb-sia, passdb-vpopmail and userdb-vpopmail.
	* auth: Removed postfix postmap socket
	+ auth: Added new fields for auth server events. These fields are now
	  also available for all auth events. See
	  https://doc.dovecot.org/admin_manual/list_of_events/#authentication-server
	  for details.
	+ imap-hibernate: Added imap_client_hibernated, imap_client_unhibernated
	  and imap_client_unhibernate_retried events. See
	  https://doc.dovecot.org/admin_manual/list_of_events/ for details.
	+ lib-index: Added new mail_index_recreated event. See
	  https://doc.dovecot.org/admin_manual/list_of_events/#mail-index-recreated
	+ lib-sql: Support TLS options for cassandra driver. This requires
	  cpp-driver v2.15 (or later) to work reliably.
	+ lib-storage: Missing $HasAttachment / $HasNoAttachment flags are now
	  added to existing mails if mail_attachment_detection_option=add-flags
	  and it can be done inexpensively.
	+ login proxy: Added login_proxy_max_reconnects setting (default 3) to
	  control how many reconnections are attempted.
	+ login proxy: imap/pop3/submission/managesieve proxying now supports
	  reconnection retrying on more than just connect() failure. Any error
	  except a non-temporary authentication failure will result in reconnect
	  attempts.
	- auth: Lua passdb/userdb leaks stack elements per call, eventually
	  causing the stack to become too deep and crashing the auth or
	  auth-worker process.
	- auth: SASL authentication PLAIN mechanism could be used to trigger
	  read buffer overflow. However, this doesn't seem to be exploitable in
	  any way.
	- auth: v2.3.11 regression: GSSAPI authentication fails because dovecot
	  disallows NUL bytes for it.
	- dict: Process used too much CPU when iterating keys, because each key
	  used a separate write() syscall.
	- doveadm-server: Crash could occur if logging was done outside command
	  handling. For example http-client could have done debug logging
	  afterwards, resulting in either segfault or
	  Panic: file http-client.c: line 642 (http_client_context_close):
	  assertion failed: (cctx->clients_list == NULL).
	- doveadm-server: v2.3.11 regression: Trying to connect to doveadm server
	  process via starttls assert-crashed if there were no ssl=yes listeners:
	  Panic: file master-service-ssl.c: line 22 (master_service_ssl_init):
	  assertion failed: (service->ssl_ctx_initialized).
	- fts-solr: HTTP requests may have assert-crashed:
	  Panic: file http-client-request.c: line 1232 (http_client_request_send_more):
	  assertion failed: (req->payload_input != NULL)
	- imap: IMAP NOTIFY could crash with a segmentation fault due to a bad
	  configuration that causes errors. Sending the error responses to the
	  client can cause the segmentation fault. This can for example happen
	  when several namespaces use the same mail storage location.
	- imap: IMAP NOTIFY used on a shared namespace that doesn't actually
	  exist (e.g. public namespace for a nonexistent user) can crash with a panic:
	  Panic: Leaked view for index /tmp/home/asdf/mdbox/dovecot.list.index: Opened in (null):0
	- imap: IMAP session can crash with QRESYNC extension if many changes
	  are done before asking for expunged mails since last sync.
	- imap: Process might hang indefinitely if client disconnects after
	  sending some long-running commands pipelined, for example FETCH+LOGOUT.
	- lib-compress: Mitigate crashes when configuring a not compiled in
	  compression. Errors with compression configuration now distinguish
	  between not supported and unknown.
	- lib-compression: Using xz/lzma compression in v2.3.11 could have
	  written truncated output in some situations. This would result in
	  "Broken pipe" read errors when trying to read it back.
	- lib-compression: zstd compression could have crashed in some situations:
	  Panic: file ostream.c: line 287 (o_stream_sendv_int): assertion failed: (!stream->blocking)
	- lib-dict: dict client could have crashed in some rare situations when
	  iterating keys.
	- lib-http: Fix several assert-crashes in HTTP client.
	- lib-index: v2.3.11 regression: When mails were expunged at the same
	  time as lots of new content was being saved to the cache (e.g. cache
	  file was lost and is being re-filled) a deadlock could occur with
	  dovecot.index.cache / dovecot.index.log.
	- lib-index: v2.3.11 regression: dovecot.index.cache file was being
	  purged (rewritten) too often when it had a field that hadn't been
	  accessed for over 1 month, but less than 2 months. Every cache file
	  change caused a purging in this situation.
	- lib-mail: MIME parts were not returned correctly by Dovecot MIME parser.
	  Regression caused by fixing CVE-2020-12100.
	- lib-mail: When max nested MIME parts were reached, IMAP BODYSTRUCTURE
	  was written in a way that may have caused confusion for both IMAP
	  clients and Dovecot itself when parsing it. The truncated part is now
	  written out using application/octet-stream MIME type.
	- lib-mail: v2.3.11 regression: Mail delivery / parsing crashed when the
	  10000th MIME part was message/rfc822 (or if parent was multipart/digest):
	  Panic: file message-parser.c: line 167 (message_part_append):
	  assertion failed: (ctx->total_parts_count <= ctx->max_total_mime_parts).
	- lib-oauth2: Dovecot incorrectly required oauth2 server introspection
	  reply to contain username with invalid token.
	- lib-ssl-iostream, lib-dcrypt: Fix building with OpenSSL that has
	  deprecated APIs disabled.
	- lib-storage: When mail's size is different from the cached one (in
	  dovecot.index.cache or Maildir S=size in the filename), this is
	  handled by logging "Cached message size smaller/larger than expected"
	  error. However, in some situations this also ended up crashing with:
	  Panic: file istream.c: line 315 (i_stream_read_memarea):
	  assertion failed: (old_size <= _stream->pos - _stream->skip).
	- lib-storage: v2.3 regression: Copying/moving mails was taking much more
	  memory than before. This was mainly visible when copying/moving
	  thousands of mails in a single transaction.
	- lib-storage: v2.3.11 regression: Searching messages assert-crashed
	  (without FTS): Panic: file message-parser.c: line 174 (message_part_finish):
	  assertion failed: (ctx->nested_parts_count > 0).
	- lib: Dovecot v2.3 moved signal handlers around in ioloops,
	  causing more CPU usage than in v2.2.
	- lib: Fixed JSON parsing: '\' escape sequence may have wrongly resulted
	  in error if it happened to be at read boundary. Any NUL characters and
	  '\u0000' will now result in parsing error instead of silently
	  truncating the data.
	- lmtp, submission: Server may hang if SSL client connection disconnects
	  during the delivery. If this happened repeated, it could have ended
	  up reaching process_limit and preventing any further lmtp/submission
	  deliveries.
	- lmtp: Proxy does not always properly log TLS connection problems as
	  errors; in some cases, only a debug message is logged if enabled.
	- lmtp: The LMTP service can hang when commands are pipelined. This can
	  particularly occur when one command in the middle of the pipeline fails.
	  One example of this occurs for proxied LMTP transactions in which the
	  final DATA or BDAT command is pipelined after a failing RCPT command.
	- login-proxy: The login_source_ips setting has no effect, and therefore
	  the proxy source IPs are not cycled through as they should be.
	- master: Process was using 100% CPU in some situations when a broken
	  service was being throttled.
	- pop3-login: POP3 login would fail with "Input buffer full" if the
	  initial response for SASL was too long.
	- stats: Crash would occur when generating openmetrics data for metrics
	  using aggregating functions.

v2.3.11.3 2020-07-29	Aki Tuomi <aki.tuomi@open-xchange.com>

	- pop3-login: Login didn't handle commands in multiple IP packets properly.
	  This mainly affected large XCLIENT commands or a large SASL initial
	  response parameter in the AUTH command.
	- pop3: pop3_deleted_flag setting was broken, causing:
	  Panic: file seq-range-array.c: line 472 (seq_range_array_invert):
	  assertion failed: (range[count-1].seq2 <= max_seq)

v2.3.11.2 2020-07-13	Aki Tuomi <aki.tuomi@open-xchange.com>

	- auth: Lua passdb/userdb leaks stack elements per call, eventually
	  causing the stack to become too deep and crashing the auth or
	  auth-worker process.
	- lib-mail: v2.3.11 regression: MIME parts not returned correctly by
	  Dovecot MIME parser.
	- pop3-login: Login would fail with "Input buffer full" if the initial
	  response for SASL was too long.

v2.3.11 2020-06-17  Aki Tuomi <aki.tuomi@open-xchange.com>

	* CVE-2020-12100: Parsing mails with a large number of MIME parts could
	  have resulted in excessive CPU usage or a crash due to running out of
	  stack memory.
	* CVE-2020-12673: Dovecot's NTLM implementation does not correctly check
	  message buffer size, which leads to reading past allocation which can
	  lead to crash.
	* CVE-2020-10967: lmtp/submission: Issuing the RCPT command with an
	  address that has the empty quoted string as local-part causes the lmtp
	  service to crash.
	* CVE-2020-12674: Dovecot's RPA mechanism implementation accepts
	  zero-length message, which leads to assert-crash later on.
	* Events: Fix inconsistency in events. See event documentation in
	  https://doc.dovecot.org.
	* imap_command_finished event's cmd_name field now contains "unknown"
	  for unknown commands. A new "cmd_input_name" field contains the
	  command name exactly as it was sent.
	* lib-index: Renamed mail_cache_compress_* settings to mail_cache_purge_*.
	  Note that these settings are mainly intended for testing and usually
	  shouldn't be changed.
	* events: Renamed "index" event category to "mail-index".
	* events: service:<name> category is now using the name from
	  configuration file.
	* dns-client: service dns_client was renamed to dns-client.
	* log: Prefixes generally use the service name from configuration file.
	  For example dict-async service will now use
	  "dict-async(pid): " log prefix instead of "dict(pid): "
	* *-login: Changed logging done by proxying to use a consistent prefix
	  containing the IP address and port.
	* *-login: Changed disconnection log messages to be slightly clearer.
	+ dict: Add events for dictionaries.
	+ lib-index: Finish logging with events.
	+ oauth2: Support local validation of JWT tokens.
	+ stats: Add support for dynamic histograms and grouping. See
	  https://doc.dovecot.org/configuration_manual/stats/.
	+ imap: Implement RFC 8514: IMAP SAVEDATE
	+ lib-index: If a long-running transaction (e.g. SORT/FETCH on a huge
	  folder) adds a lot of data to dovecot.index.cache file, commit those
	  changes periodically to make them visible to other concurrent sessions
	  as well.
	+ stats: Add OpenMetrics exporter for statistics. See
	  https://doc.dovecot.org/configuration_manual/stats/openmetrics/.
	+ stats: Support disabling stats-writer socket by setting
	  stats_writer_socket_path="".
	- auth-worker: Process keeps slowly increasing its memory usage and
	  eventually dies with "out of memory" due to reaching vsz_limit.
	- auth: Prevent potential timing attacks in authentication secret
	  comparisons: OAUTH2 JWT-token HMAC, imap-urlauth token, crypt() result.
	- auth: Several auth-mechanisms allowed input to be truncated by NUL
	  which can potentially lead to unintentional issues or even successful
	  logins which should have failed.
	- auth: When auth policy returned a delay, auth_request_finished event
	  had policy_result=ok field instead of policy_result=delayed.
	- auth: auth process crash when auth_policy_server_url is set to an
	  invalid URL.
	- dict-ldap: Crash occurs if var_expand template expansion fails.
	- dict: If dict client disconnected while iteration was still running,
	  dict process could have started using 100% CPU, although it was still
	  handling clients.
	- doveadm: Running doveadm commands via proxying may hang, especially
	  when doveadm is printing a lot of output.
	- imap: "MOVE * destfolder" goes to a loop copying the last mail to the
	  destination until the imap process dies due to running out of memory.
	- imap: Running "UID MOVE 1:* Trash" on an empty folder goes to infinite
	  loop.
	- imap: SEARCH doesn't support $.
	- lib-compress: Buffer over-read in zlib stream read.
	- lib-dns: If DNS lookup times out, lib-dns can cause crash in calling
	  process.
	- lib-index: Fixed several bugs in dovecot.index.cache handling that
	  could have caused cached data to be lost.
	- lib-index: Writing to >=1 GB dovecot.index.cache files may cause
	  assert-crashes:
	  Panic: file mail-index-util.c: line 37 (mail_index_uint32_to_offset):
	  assertion failed: (offset < 0x40000000)
	- lib-ssl-iostream: Fix buggy OpenSSL error handling without
	  assert-crashing. If there is no error available, log it as an error
	  instead of crashing:
	  Panic: file iostream-openssl.c: line 599 (openssl_iostream_handle_error):
	  assertion failed: (errno != 0)
	- lib-ssl-iostream: ssl_key_password setting did not work.
	- submission: A segfault crash may occur when the client or server
	  disconnects while a non-transaction command like NOOP or VRFY is still
	  being processed.
	- virtual: Copying/moving mails with IMAP into a virtual folder assert-crashes:
	  Panic: file cmd-copy.c: line 152 (fetch_and_copy): assertion failed:
	  (copy_ctx->copy_count == seq_range_count(&copy_ctx->saved_uids))

v2.3.10  2020-03-06  Aki Tuomi <aki.tuomi@open-xchange.com>

	* Disable retpoline migitations by default. These can cause severe
	  performance regressions, so they should be only enabled when
	  applicable.
	* IMAP MOVE now commits transactions in batches of 1000 mails. This
	  helps especially with lazy_expunge when moving a lot of mails. It
	  mainly avoids situations where multiple IMAP sessions are running the
	  same MOVE command and duplicating the mails in the lazy_expunge folder.
	  With this change there can still be some duplication, but the MOVE
	  always progresses forward. Also if the MOVE fails at some point, the
	  changes up to the last 1000 mails are still committed instead of
	  rolled back. Note that the COPY command behavior hasn't changed,
	  because it is required by IMAP standard to be an atomic operation.
	* IMAP EXPUNGE and CLOSE now expunges mails in batches of 1000 mails.
	  This helps especially with lazy_expunge when expunging a lot of mails
	  (e.g. millions) to make sure that the progress always moves forward
	  even if the process is killed.
	* Autoexpunging now expunges mails in batches of 1000 mails. This helps
	  especially with lazy_expunge when expunging a lot of mails
	  (e.g. millions) to make sure that the progress always moves forward
	  even if the process is killed.
	+ Add tool for generating sysreport called dovecot-sysreport.
	  This generates a bundle of information usually needed for support
	  requests.
	+ Add support for the new IMAP \Important SPECIAL-USE flag (RFC 8457).
	+ Add metric { group_by } setting. This allows automatically creating
	  new metrics based on the fields you want to group statistics by.
	  NOTE: This feature is considered experimental and syntax is subject
	  to change in future release.
	+ auth: Support SCRAM-SHA-256 authentication mechanism.
	+ imap: Support the new IMAP STATUS=SIZE extension.
	+ Use TCP_QUICKACK to reduce latency for some TCP connections.
	+ quota-status: Made the service more robust against erroneous use with
	  Postfix ACL policies other than smtpd_recipient_restrictions.
	+ Add "revision" field support to imap_id_send setting. Using
	  "revision *" will send in IMAP ID command response the short commit
	  hash of the Dovecot git source tree HEAD (same as in dovecot --version).
	+ IMAP ENVELOPE includes now all addresses when there are multiple
	  headers (From, To, Cc, etc.) The standard way of having multiple
	  addresses is to just list them all in a single header. It's
	  non-standard to have multiple headers. However, since MTAs allow these
	  mails to pass through and different software may handle them in
	  different ways, it's better from security point of view to show all
	  the addresses.
	+ Event filters now support using "field_name=" to match a field that
	  doesn't exist or has an empty value. For example use "error=" to match
	  only events that didn't fail.
	- acl: INBOX ACLs shouldn't apply for IMAP GETMETADATA/SETMETADATA
	  commands.
	- cassandra: CASS_ERROR_SERVER_WRITE_FAILURE error should also be
	  treated as "uncertain write failure".
	- dict-redis: Using quota_clone configured with dict-redis could have
	  crashed when Redis responded slowly.
	- imap-hibernate: Communication trouble with imap-master leads to
	  segfault.
	- imap-hibernate: Unhibernation retrying wasn't working.
	- imap: Fixed auth lookup privilege problem when imap process was reused
	  and user was being un-hibernated.
	- Fix potential crash when copying/moving mails within the same folder.
	  This happened only when there were a lot of fields in dovecot.index.cache.
	- lib-index: Recreating dovecot.index.cache file could have crashed when
	  merging bitmask fields.
	- lib-index: Using public/shared folders with INDEXPVT configured to use
	  private \Seen flags, trying to search seen/unseen in an empty folder
	  crashes with segfault.
	- lib-mail: Large base64-encoded mails weren't decoded properly.
	  This could have affected searching/indexing mails and message snippet
	  generation.
	- lib-mail: Message with only quoted text could have caused message
	  snippet to ignore its 200 character limit and return the entire
	  message. This was added also to dovecot.index.cache file, which
	  increased disk space and memory usage unnecessarily.
	  v2.3.9.2 regression (previous versions cached the quoted snippet as
	  empty). In a large mail quoted text could have become wrongly added
	  to the snippet, possibly mixed together with non-quoted text.
	- lib-smtp: client could have assert-crashed if STARTTLS handshake
	  finished earlier than usually.
	- lib-ssl-iostream: remove -static flag for lib-ssl-iostream linking to
	  prevent a compile issue.
	- lib-storage: Mailbox synchronization may have assert-crashed in some
	  rare situations.
	- lib-storage: mdbox didn't preserve date.saved with dsync.
	- lib: Don't require EAI_{ADDRFAMILY,NODATA}, breaks FreeBSD
	- master: Some services could respawn unthrottled if they crash during
	  startup.
	- push-notification: Do not send push_notification_finished event if
	  nothing was done. This happens when mail transaction is started and
	  ended with no changes.
	- quota-status: Addresses with special characters in the local part caused
	  problems in the interaction between Postfix and Dovecot. Postfix sent
	  its own internal representation in the recipient field, while Dovecot
	  expected a valid RFC5321 mailbox address.
	- submission-login: SESSION was not correctly encoded field for the
	  XCLIENT command. Particularly, a '+' character introduced by the
	  session ID's Base64 encoding causes problems.
	- submission: Fix submission_max_mail_size to work correctly on 32-bit
	  systems.
	- submission: Trusted connections crashed in second connection's EHLO
	  if submission-login { service_count } is something else than 1 (which
	  is the default).
	- submission: XCLIENT command was never used in the protocol exchange
	  with the relay MTA when submission_backend_capabilities is configured,
	  even when the relay MTA was properly configured to accept the XCLIENT
	  command.

v2.3.9.3 2020-02-12  Aki Tuomi <aki.tuomi@open-xchange.com>

	* CVE-2020-7046: Truncated UTF-8 can be used to DoS
	  submission-login and lmtp processes.
	* CVE-2020-7957: Specially crafted mail can crash snippet generation.

v2.3.9.2 2019-12-13  Aki Tuomi <aki.tuomi@open-xchange.com>

	- Mails with empty From/To headers can also cause crash
	  in push notification drivers.

v2.3.9.1 2019-12-13  Aki Tuomi <aki.tuomi@open-xchange.com>

	* CVE-2019-19722: Mails with group addresses in From or To fields
	  caused crash in push notification drivers.

v2.3.9 2019-12-04  Aki Tuomi <aki.tuomi@open-xchange.com>

	* Changed several event field names for consistency and to avoid
	  conflicts in parent-child event relationships:
	   * SMTP server command events: Renamed "name" to "cmd_name"
	   * Events inheriting from a mailbox: Renamed "name" to "mailbox"
	   * Server connection events have only "remote_ip", "remote_port",
	     "local_ip" and "local_port".
	   * Removed duplicate "client_ip", "ip" and "port".
	   * Mail storage events: Removed "service" field.
	     Use "service:<name>" category instead.
	   * HTTP client connection events: Renamed "host" to "dest_host" and
	     "port" to "dest_port"
	* auth: Drop Postfix socketmap support. It hasn't been working
	  with recent Postfix versions for a while now.
	* push-notification-lua: The "subject" field is now decoded to UTF8
	  instead of kept as MIME-encoded.
	+ push-notification-lua: Added new "from_address", "from_display_name",
	  "to_address" and "to_display_name" fields. The display names are
	  decoded to UTF8.
	+ Added various new fields to existing events.
	  See http://doc.dovecot.net/admin_manual/list_of_events.html
	+ Add lmtp_add_received_header setting. It can be used to prevent LMTP
	  from adding "Received:" headers.
	+ doveadm: Support SSL/STARTTLS for proxied doveadm connections based on
	  doveadm_ssl setting and proxy ssl/tls settings.
	+ Log filters support now "service:<name>", which matches all events for
	  the given service. It can also be used as a category.
	+ lib: Use libunwind to get abort backtraces with function names
	  where available.
	+ lmtp: When the LMTP proxy changes the username (from passdb lookup)
	  add an appropriate ORCPT parameter.
	- lmtp: Add lmtp_client_workarounds setting to implement workarounds for
	  clients that send MAIL and RCPT commands with additional spaces before
	  the path and for clients that omit <> brackets around the path.
	  See example-config/conf.d/20-lmtp.conf.
	- lda/lmtp: Invalid MAIL FROM addresses were rejcted too aggressively.
	  Now mails from addresses with unicode characters are delivered, but
	  their Return-Path header will be <> instead of the given MAIL FROM
	  address.
	- lmtp: The lmtp_hdr_delivery_address setting is ignored.
	- imap: imap_command_finished event's "args" and "human_args" parameters
	  were always empty.
	- mbox: Seeking in zlib and bzip2 compressed input streams didn't work
	  correctly.
	- imap-hibernate: Process crashed when client got destroyed while it was
	  attempted to be unhibernated, and the unhibernation fails.
	- *-login: Proxying may have crashed if SSL handshake to the backend
	  failed immediately. This was unlikely to happen in normal operation.
	- *-login: If TLS handshake to upstream server failed during proxying,
	  login process could crash due to invalid memory access.
	- *-login: v2.3 regression: Using SASL authentication without initial
	  response may have caused SSL connections to hang. This happened often
	  at least with PHP's IMAP library.
	- *-login: When login processes are flooded with authentication attempts
	  it starts logging errors about "Authentication server sent unknown id".
	  This is still expected. However, it also caused the login process to
	  disconnect from auth server and potentially log some user's password
	  in the error message.
	- dict-sql: SQL prepared statements were not shared between sessions.
	  This resulted in creating a lot of prepared statements, which was
	  especially inefficient when using Cassandra backend with a lot of
	  Cassandra nodes.
	- auth: auth_request_finished event didn't have success=yes parameter
	  set for successful authentications.
	- auth: userdb dict - Trying to list users crashed.
	- submission: Service could be configured to allow anonymous
	  authentication mechanism and anonymous user access.
	- LAYOUT=index: Corrupted dovecot.list.index caused folder creation to
	  panic.
	- doveadm: HTTP server crashes if request target starts with double "/".
	- dsync: Remote dsync started hanging if the initial doveadm
	  "dsync-server" command was sent in the same TCP packet as the
	  following dsync handshake. v2.3.8 regression.
	- lib: Several "input streams" had a bug that in some rare situations
	  might cause it to access freed memory. This could lead to crashes or
	  corruption.
	  The only currently known effect of this is that using zlib plugin with
	  external mail attachments (mail_attachment_dir) could cause fetching
	  the mail to return a few bytes of garbage data at the beginning of the
	  header. Note that the mail wasn't saved corrupted, but fetching it
	  caused corrupted mail to be sent to the client.
	- lib-storage: If a mail only has quoted content, use the quoted text
	  for generating message snippet (IMAP PREVIEW) instead of returning
	  empty snippet.
	- lib-storage: When vsize header was rebuilt, newly calculated message
	  sizes were added to dovecot.index.cache instead of being directly
	  saved into vsize records in dovecot.index.
	- lib: JSON generator was escaping UTF-8 characters unnecessarily.

v2.3.8 2019-10-08  Aki Tuomi <aki.tuomi@open-xchange.com>

	+ Added mail_delivery_started and mail_delivery_finished events, see
	  https://doc.dovecot.org/admin_manual/list_of_events/ for details.
	+ dsync-replication: Don't replicate users who have "noreplicate" extra
	  field in userdb.
	+ doveadm service status: Show total number of processes created.
	+ When logging to syslog, use instance_name setting's value for the
	  ident. This commonly is added as a log prefix.
	+ Base64 encoding/decoding code was rewritten with additional features.
	  It shouldn't cause any user visible changes.
	- v2.3.7 regression: If a folder only receives new mails without any
	  other mail access, dovecot.index.log keeps growing forever and
	  dovecot.index keeps being rewritten for every mail delivery.
	- dsync-replication may lose keywords after syncing mails restored from
	  another replica. This only happened if the mail only had keywords and
	  no system flags.
	- event filters: Non-textual event fields could not be filtered using
	  wildcards.
	- auth: Scope parameter was missing from OAuth password grant
	  request.
	- doveadm client-server communication may hang in some situations.
	  It is also using unnecessarily small TCP/IP packet sizes.
	- doveadm who and kick did not flush protocol output correctly.
	- imap: SETMETADATA with literal value would delete the metadata value
	  instead of updating it.
	- imap: When client issues FETCH PREVIEW (LAZY=FUZZY) command, the
	  caching decisions should be updated so that newly saved mails will
	  have the preview cached.
	- With mail_nfs_index=yes and/or mail_nfs_storage=yes setuid/setgid
	  permission bits in some files may have become dropped with some NFS
	  servers. Changed NFS flushing to now use chmod() instead of chown().
	- quota: warnings did not work if quota root was noenforcing
	- acl: Global ACL file ignored the last line if it didn't end with LF.
	- doveadm stats dump: With JSON formatter output numbers using the
	  number type instead of as strings
	- lmtp_proxy: Ensure that real_* variables are correctly set when using
	  lmtp_proxy.
	- event exporter: http-post driver had hardcoded timeout and did not
	  support DNS lookups or TLS connections.
	- auth: Fix user iteration to work with userdb passwd with glibc v2.28.
	- auth: auth service can crash if auth-policy JSON response is invalid
	  or returned too fast.
	- In some rare situations "ps" output could have shown a lot of "?"
	  characters after Dovecot process titles.
	- When dovecot.index.pvt is empty, an unnecessary error is logged:
	  Error: .../dovecot.index.pvt reset, view is now inconsistent
	- SMTP address encoder duplicated initial double quote character when
	  the localpart of an address ended in '..'. For example
	  "user+..@example.com" became ""user+.."@example.com in a
	  sieve redirect.

v2.3.7.1 2019-07-23  Timo Sirainen <timo.sirainen@open-xchange.com>

	- Fix TCP_NODELAY errors being logged on non-Linux OSes
	- lmtp proxy: Fix assert-crash when client uses BODY=8BITMIME
	- Remove wrongly added checks in namespace prefix checking

v2.3.7 2019-07-12  Aki Tuomi <aki.tuomi@open-xchange.com>

	* fts-solr: Removed break-imap-search parameter
	+ Added more events for the new statistics, see
	  https://doc.dovecot.org/admin_manual/list_of_events/
	+ mail-lua: Add IMAP metadata accessors, see
	  https://doc.dovecot.org/admin_manual/lua/
	+ Add event exporters that allow exporting raw events to log files and
	  external systems, see
	  https://doc.dovecot.org/configuration_manual/event_export/
	+ SNIPPET is now PREVIEW and size has been increased to 200 characters.
	+ Add body option to fts_enforced. This triggers building FTS index only
	  on body search, and an error using FTS index fails the search rather
	  than reads through all the mails.
	- Submission/LMTP: Fixed crash when domain argument is invalid in a
	  second EHLO/LHLO command.
	- Copying/moving mails using Maildir format loses IMAP keywords in the
	  destination if the mail also has no system flags.
	- mail_attachment_detection_options=add-flags-on-save caused email body
	  to be unnecessarily opened when FETCHing mail headers that were
	  already cached.
	- mail attachment detection keywords not saved with maildir.
	- dovecot.index.cache may have grown excessively large in some
	  situations. This happened especially when using autoexpunging with
	  lazy_expunge folders. Also with mdbox format in general the cache file
	  wasn't recreated as often as it should have.
	- Autoexpunged mails weren't immediately deleted from the disk. Instead,
	  the deletion from disk happened the next time the folder was opened.
	  This could have caused unnecessary delays if the opening was done by
	  an interactive IMAP session.
	- Dovecot's TCP connections sometimes add extra 40ms latency due to not
	  enabling TCP_NODELAY. HTTP and SMTP/LMTP connections weren't
	  affected, but everything else was. This delay wasn't always visible -
	  only in some situations with some message/packet sizes.
	- imapc: Fix various crash conditions
	- Dovecot builds were not always reproducible.
	- login-proxy: With shutdown_clients=no after config reload the
	  existing connections could no longer be listed or kicked with doveadm.
	- "doveadm proxy kick" with -f parameter caused a crash in some
	  situations.
	- Auth policy can cause segmentation fault crash during auth process
	  shutdown if all auth requests have not been finished.
	- Fix various minor bugs leading into incorrect behaviour in mailbox
	  list index handling. These rarely caused noticeable problems.
	- LDAP auth: Iteration accesses freed memory, possibly crashing
	  auth-worker
	- local_name { .. } filter in dovecot.conf does not correctly support
	  multiple names and wildcards were matched incorrectly.
	- replicator: dsync assert-crashes if it can't connect to remote TCP
	  server.
	- config: Memory leak in config process when ssl_dh setting wasn't
	  set and there was no ssl-parameters.dat file.
	  This caused config process to die once in a while
	  with "out of memory".

v2.3.6 2019-04-30  Aki Tuomi <aki.tuomi@open-xchange.com>

	* CVE-2019-11494: Submission-login crashed with signal 11 due to null
	  pointer access when authentication was aborted by disconnecting.
	* CVE-2019-11499: Submission-login crashed when authentication was
	  started over TLS secured channel and invalid authentication message
	  was sent.
	* auth: Support password grant with passdb oauth2.
	+ Use system default CAs for outbound TLS connections.
	+ Simplify array handling with new helper macros.
	+ fts_solr: Enable configuring batch_size and soft_commit features.
	- lmtp/submission: Fixed various bugs in XCLIENT handling, including a
	  hang when XCLIENT commands were sent infinitely to the remote server.
	- lmtp/submission: Forwarded multi-line replies were erroneously sent
	  as two replies to the client.
	- lib-smtp: client: Message was not guaranteed to contain CRLF
	  consistently when CHUNKING was used.
	- fts_solr: Plugin was no longer compatible with Solr 7.
	- Make it possible to disable certificate checking without
	  setting ssl_client_ca_* settings.
	- pop3c: SSL support was broken.
	- mysql: Closing connection twice lead to crash on some systems.
	- auth: Multiple oauth2 passdbs crashed auth process on deinit.
	- HTTP client connection errors infrequently triggered a segmentation
	  fault when the connection was idle and not used for a particular
	  client instance.

v2.3.5.2 2019-04-18  Timo Sirainen <tss@iki.fi>

	* CVE-2019-10691: Trying to login with 8bit username containing
	  invalid UTF8 input causes auth process to crash if auth policy is
	  enabled. This could be used rather easily to cause a DoS. Similar
	  crash also happens during mail delivery when using invalid UTF8 in
	  From or Subject header when OX push notification driver is used.

v2.3.5.1 2019-03-28  Timo Sirainen <tss@iki.fi>

	* CVE-2019-7524: Missing input buffer size validation leads into
	  arbitrary buffer overflow when reading fts or pop3 uidl header
	  from Dovecot index. Exploiting this requires direct write access to
	  the index files.

v2.3.5 2019-03-05  Timo Sirainen <tss@iki.fi>

	+ Lua push notification driver: mail keywords and flags are provided
	  in MessageNew and MessageAppend events.
	+ submission: Implement support for plugins.
	+ auth: When auth_policy_log_only=yes, only log what the policy server
	  response would do without actually doing it.
	+ auth: Always log policy server decisions with auth_verbose=yes
	- v2.3.[34]: doveadm log errors: Output was missing user/session
	- lda: Debug log lines could have shown slightly corrupted
	- login proxy: Login processes may have crashed in various ways when
	  login_proxy_max_disconnect_delay was set.
	- imap: Fix crash with Maildir+zlib if client disconnects during APPEND
	- lmtp proxy: Fix potential assert-crash
	- lmtp/submission: Fix crash when SMTP client transaction times out
	- submission: Split large XCLIENT commands to 512 bytes per command,
	  so Postfix accepts them.
	- submission: Fix crash when client sends invalid BURL command
	- submission: relay backend: VRFY command: Avoid forwarding 500 and
	  502 replies back to client.
	- lib-http: Fix potential assert-crash when DNS lookup fails
	- lib-fts: Fix search query generation when one language ignores a
	  token (e.g. via stopwords).

v2.3.4 2018-11-23  Timo Sirainen <tss@iki.fi>

	* The default postmaster_address is now "postmaster@<user domain or
	  server hostname>". If username contains the @domain part, that's
	  used. If not, then the server's hostname is used.
	* "doveadm stats dump" now returns two decimals for the "avg" field.

	+ Added push notification driver that uses a Lua script
	+ Added new SQL, DNS and connection events.
	  See https://wiki2.dovecot.org/Events
	+ Added "doveadm mailbox cache purge" command.
	+ Added events API support for Lua scripts
	+ doveadm force-resync -f parameter performs "index fsck" while opening
	  the index. This may be useful to fix some types of broken index files.
	  This may become the default behavior in a later version.
	- director: Kicking a user crashes if login process is very slow
	- pop3_no_flag_updates=no: Don't expunge DELEted and RETRed messages
	  unless QUIT is sent.
	- auth: Fix crypt() segfault with glibc-2.28+
	- imap: Running UID FILTER script with errors assert-crashes
	- dsync, pop3-migration: POP3 UIDLs weren't added to
	  dovecot.index.cache while mails were saved.
	- dict clients may have been using 100% CPU while waiting for dict
	  server to finish commands.
	- doveadm user: Fixed user listing via HTTP API
	- All levels of Cassandra log messages were logged as Dovecot errors.
	- http/smtp client may have crashed after SSL handshake
	- Lua auth converted strings that looked like numbers into numbers.


v2.3.3 2018-10-01  Timo Sirainen <tss@iki.fi>

	* doveconf hides more secrets now in the default output.
	* ssl_dh setting is no longer enforced at startup. If it's not set and
	  non-ECC DH key exchange happens, error is logged and client is
	  disconnected.

	+ Added log_debug=<filter> setting.
	+ Added log_core_filter=<log filter> setting.
	+ quota-clone: Write to dict asynchronously
	+ --enable-hardening attempts to use retpoline Spectre 2 mitigations
	+ lmtp proxy: Support source_ip passdb extra field.
	+ doveadm stats dump: Support more fields and output stddev by default.
	+ push-notification: Add SSL support for OX backend.
	- NUL bytes in mail headers can cause truncated replies when fetched.
	- director: Conflicting host up/down state changes may in some rare
	  situations ended up in a loop of two directors constantly overwriting
	  each others' changes.
	- director: Fix hang/crash when multiple doveadm commands are being
	  handled concurrently.
	- director: Fix assert-crash if doveadm disconnects too early
	- virtual plugin: Some searches used 100% CPU for many seconds
	- dsync assert-crashed with acl plugin in some situations.
	- mail_attachment_detection_options=add-flags-on-save assert-crashed
	  with some specific Sieve scripts.
	- Mail snippet generation crashed with mails containing invalid
	  Content-Type:multipart header.
	- Log prefix ordering was different for some log lines.
	- quota: With noenforcing option current quota usage wasn't updated.
	- auth: Kerberos authentication against Samba assert-crashed.
	- stats clients were unnecessarily chatty with the stats server.
	- imapc: Fixed various assert-crashes when reconnecting to server.
	- lmtp, submission: Fix potential crash if client disconnects while
	  handling a command.
	- quota: Fixed compiling with glibc-2.26 / support libtirpc.
	- fts-solr: Empty search values resulted in 400 Bad Request errors
	- fts-solr: default_ns parameter couldn't be used
	- submission server crashed if relay server returned over 7 lines in
	  a reply (e.g. to EHLO)

v2.3.2.1 2018-07-09  Timo Sirainen <tss@iki.fi>

	- SSL/TLS servers may have crashed during client disconnection
	- lmtp: With lmtp_rcpt_check_quota=yes mail deliveries may have
	  sometimes assert-crashed.
	- v2.3.2: "make check" may have crashed with 32bit systems

v2.3.2 2018-06-29  Timo Sirainen <tss@iki.fi>

	* old-stats plugin: Don't temporarily enable PR_SET_DUMPABLE while
	  opening /proc/self/io. This may still cause security problems if the
	  process is ptrace()d at the same time. Instead, open it while still
	  running as root.
	+ doveadm: Added mailbox cache decision&remove commands. See
	  doveadm-mailbox(1) man page for details.
	+ doveadm: Added rebuild attachments command for rebuilding
	  $HasAttachment or $HasNoAttachment flags for matching mails. See
	  doveadm-rebuild(1) man page for details.
	+ cassandra: Use fallback_consistency on more types of errors
	+ lmtp proxy: Support outgoing SSL/TLS connections
	+ lmtp: Add lmtp_rawlog_dir and lmtp_proxy_rawlog_dir settings.
	+ submission: Add support for rawlog_dir
	+ submission: Add submission_client_workarounds setting.
	+ lua auth: Add password_verify() function and additional fields in
	  auth request.
	- doveadm-server: TCP connections are hanging when there is a lot of
	  network output. This especially caused hangs in dsync-replication.
	- Using multiple type=shared mdbox namespaces crashed
	- mail_fsync setting was ignored. It was always set to "optimized".
	- lua auth: Fix potential crash at deinit
	- SSL/TLS servers may have crashed if client disconnected during
	  handshake.
	- SSL/TLS servers: Don't send extraneous certificates to client when
	  alt certs are used.
	- lda, lmtp: Return-Path header without '<' may have assert-crashed.
	- lda, lmtp: Unencoded UTF-8 in email address headers may assert-crash
	- lda: -f parameter didn't allow empty/null/domainless address
	- lmtp, submission: Message size limit was hardcoded to 40 MB.
	  Exceeding it caused the connection to get dropped during transfer.
	- lmtp: Fix potential crash when delivery fails at DATA stage
	- lmtp: login_greeting setting was ignored
	- Fix to work with OpenSSL v1.0.2f
	- systemd unit restrictions were too strict by default
	- Fix potential crashes when a lot of log output was produced
	- SMTP client may have assert-crashed when sending mail
	- IMAP COMPRESS: Send "end of compression" marker when disconnecting.
	- cassandra: Fix consistency=quorum to work
	- dsync: Lock file generation failed if home directory didn't exist
	- Snippet generation for HTML mails didn't ignore &entities inside
	  blockquotes, producing strange looking snippets.
	- imapc: Fix assert-crash if getting disconnected and after
	  reconnection all mails in the selected mailbox are gone.
	- pop3c: Handle unexpected server disconnections without assert-crash
	- fts: Fixes to indexing mails via virtual mailboxes.
	- fts: If mails contained NUL characters, the text around it wasn't
	  indexed.
	- Obsolete dovecot.index.cache offsets were sometimes used. Trying to
	  fetch a field that was just added to cache file may not have always
	  found it.

v2.3.1 2018-02-29  Aki Tuomi <aki.tuomi@dovecot.fi>

	* Submission server support improvements and bug fixes
	  - Lots of bug fixes to submission server
	* API CHANGE: array_idx_modifiable will no longer allocate space
	  - Particularly affects how you should check MODULE_CONTEXT result, or
	    use REQUIRE_MODULE_CONTEXT.

	+ mail_attachment_detection_options setting controls when
	  $HasAttachment and $HasNoAttachment keywords are set for mails.
	+ imap: Support fetching body snippets using FETCH (SNIPPET) or
	  (SNIPPET (LAZY=FUZZY))
	+ fs-compress: Automatically detect whether input is compressed or not.
	  Prefix the compression algorithm with "maybe-" to enable the
	  detection, for example: "compress:maybe-gz:6:..."
	+ Added settings to change dovecot.index* files' optimization behavior.
	  See https://wiki2.dovecot.org/IndexFiles#Settings
	+ Auth cache can now utilize auth workers to do password hash
	  verification by setting auth_cache_verify_password_with_worker=yes.
	+ Added charset_alias plugin. See
	  https://wiki2.dovecot.org/Plugins/CharsetAlias
	+ imap_logout_format and pop3_logout_format settings now support all of
	  the generic variables (e.g. %{rip}, %{session}, etc.)
	+ Added auth_policy_check_before_auth, auth_policy_check_after_auth
	  and auth_policy_report_after_auth settings.
	+ master: Support HAProxy PP2_TYPE_SSL command and set "secured"
	  variable appropriately
	- Invalid UCS4 escape in HTML can cause crashes
	- imap: IMAP COMPRESS -enabled clietn crashes on disconnect
	- lmtp: Fix crash when user is over quota
	- lib-lda: Parsing Return-Path header address fails when it contains
	  CFWS
	- auth: SASL with Exim fails for AUTH commands without an initial
	  response
	- imap: SPECIAL-USE capability isn't automatically added
	- auth: LDAP subqueries do not support standard auth variables in
	  var-expand
	- auth: SHA256-CRYPT and SHA512-CRYPT schemes do not work
	- lib-index: mail_always/never_cache_fields are not used for existing
	  cache files
	- imap: Fetching headers leaks memory if search doesn't find any mails
	- lmtp: ORCPT support in RCPT TO
	- imap-login: Process sometimes ends up in infinite loop
	- sdbox: Rolled back save/copy transaction doesn't delete temp files
	- mail: lock_method=dotlock causes crashes

v2.3.0.1 2018-02-28  Timo Sirainen <tss@iki.fi>

	* CVE-2017-15130: TLS SNI config lookups may lead to excessive
	  memory usage, causing imap-login/pop3-login VSZ limit to be reached
	  and the process restarted. This happens only if Dovecot config has
	  local_name { } or local { } configuration blocks and attacker uses
	  randomly generated SNI servernames.
	* CVE-2017-14461: Parsing invalid email addresses may cause a crash or
	  leak memory contents to attacker. For example, these memory contents
	  might contain parts of an email from another user if the same imap
	  process is reused for multiple users. First discovered by Aleksandar
	  Nikolic of Cisco Talos. Independently also discovered by "flxflndy"
	  via HackerOne.
	* CVE-2017-15132: Aborted SASL authentication leaks memory in login
	  process.
	* Linux: Core dumping is no longer enabled by default via
	  PR_SET_DUMPABLE, because this may allow attackers to bypass
	  chroot/group restrictions. Found by cPanel Security Team. Nowadays
	  core dumps can be safely enabled by using "sysctl -w
	  fs.suid_dumpable=2". If the old behaviour is wanted, it can still be
	  enabled by setting:
	  import_environment=$import_environment PR_SET_DUMPABLE=1
	- imap-login with SSL/TLS connections may end up in infinite loop

v2.3.0 2017-12-22  Timo Sirainen <tss@iki.fi>

	* Various setting changes, see https://wiki2.dovecot.org/Upgrading/2.3
	* Logging rewrite started: Logging is now based on hierarchical events.
	  This makes it possible to do various things, like: 1) giving
	  consistent log prefixes, 2) enabling debug logging with finer
	  granularity, 3) provide logs in more machine readable formats
	  (e.g. json). Everything isn't finished yet, especially a lot of the
	  old logging code still needs to be translated to the new way.
	* Statistics rewrite started: Stats are now based on (log) events.
	  It's possible to gather statistics about any event that is logged.
	  See http://wiki2.dovecot.org/Statistics for details
	* ssl_dh setting replaces the old generated ssl-parameters.dat
	* IMAP: When BINARY FETCH finds a broken mails, send [PARSE] error
	  instead of [UNKNOWNCTE]
	* Linux: core dumping via PR_SET_DUMPABLE is no longer enabled by
	  default due to potential security reasons (found by cPanel Security
	  Team).

	+ Added support for SMTP submission proxy server, which includes
	  support for BURL and CHUNKING extension.
	+ LMTP rewrite. Supports now CHUNKING extension and mixing of
	  local/proxy recipients.
	+ auth: Support libsodium to add support for ARGON2I and ARGON2ID
	  password schemes.
	+ auth: Support BLF-CRYPT password scheme in all platforms
	+ auth: Added LUA scripting support for passdb/userdb.
	  See https://wiki2.dovecot.org/AuthDatabase/Lua
	- Input streams are more reliable now when there are errors or when
	  the maximum buffer size is reached. Previously in some situations
	  this could have caused Dovecot to try to read already freed memory.
	- Output streams weren't previously handling failures when writing a
	  trailer at the end of the stream. This mainly affected encrypt and
	  zlib compress ostreams, which could have silently written truncated
	  files if the last write happened to fail (which shouldn't normally
	  have ever happened).
	- virtual plugin: Fixed panic when fetching mails from virtual
	  mailboxes with IMAP BINARY extension.
	- doveadm-server: Fix potential hangs with SSL connections
	- doveadm proxy: Reading commands' output from v2.2.33+ servers could
	  have caused the output to be corrupted or caused a crash.
	- Many other smaller fixes

v2.2.36.3 2019-03-28  Timo Sirainen <tss@iki.fi>

	* CVE-2019-7524: Missing input buffer size validation leads into
	  arbitrary buffer overflow when reading fts or pop3 uidl header
	  from Dovecot index. Exploiting this requires direct write access to
	  the index files.

v2.2.36.1 2019-02-05  Timo Sirainen <tss@iki.fi>

	* CVE-2019-3814: If imap/pop3/managesieve/submission client has
	  trusted certificate with missing username field
	  (ssl_cert_username_field), under some configurations Dovecot
	  mistakenly trusts the username provided via authentication instead
	  of failing.
	* ssl_cert_username_field setting was ignored with external SMTP AUTH,
	  because none of the MTAs (Postfix, Exim) currently send the
	  cert_username field. This may have allowed users with trusted
	  certificate to specify any username in the authentication. This bug
	  didn't affect Dovecot's Submission service.

	- pop3_no_flag_updates=no: Don't expunge RETRed messages without QUIT
	- director: Kicking a user assert-crashes if login process is very slow
	- lda/lmtp: Fix assert-crash with some Sieve scripts when
	  mail_attachment_detection_options=add-flags-on-save
	- fs-compress: Using maybe-gz assert-crashed when reading 0 sized file
	- Snippet generation crashed with invalid Content-Type:multipart

v2.2.36 2018-05-23  Timo Sirainen <tss@iki.fi>

	* login-proxy: If ssl_require_crl=no, allow revoked certificates.
	  Also don't do CRL checks for incoming client certificates.
	* stats plugin: Don't temporarily enable PR_SET_DUMPABLE while opening
	  /proc/self/io. This may still cause security problems if the process
	  is ptrace()d at the same time. Instead, open it while still running
	  as root.

	+ doveadm: Added mailbox cache decision&remove commands. See
	  doveadm-mailbox(1) man page for details.
	+ doveadm: Added rebuild attachments command for rebuilding
	  $HasAttachment or $HasNoAttachment flags for matching mails. See
	  doveadm-rebuild(1) man page for details.
	+ cassandra: Use fallback_consistency on more types of errors
	- cassandra: Fix consistency=quorum to work
	- dsync: Lock file generation failed if home directory didn't exist
	- In some configs if namespace root directory didn't yet exist, Dovecot
	  failed to create mailboxes.lock when trying to create mailboxes
	- Snippet generation for HTML mails didn't ignore &entities inside
	  blockquotes, producing strange looking snippets.
	- imapc: Fix assert-crash if getting disconnected and after
	  reconnection all mails in the selected mailbox are gone.
	- pop3c: Handle unexpected server disconnections without assert-crash
	- fts: Fixes to indexing mails via virtual mailboxes.
	- fts: If mails contained NUL characters, the text around it wasn't
	  indexed.
	- Obsolete dovecot.index.cache offsets were sometimes used. Trying to
	  fetch a field that was just added to cache file may not have always
	  found it.
	- dict-sql: Fix crash when reading NULL value from database

v2.2.35 2018-03-19  Aki Tuomi <aki.tuomi@dovecot.fi>

	- charset_alias: compile fails with Solaris Studio, reported by
	  John Woods.
	- Fix local name handling in v2.2.34 SNI code, bug found by cPanel.
	- imapc: Don't try to add mails to index if they already exist there.
	- imapc: If email is modified in istream_opened hook, mail size isn't
	  updated.
	- lib-dcrypt: When reading encrypted data, more data would not be
	  read if buffer was not consumed causing panic or hang.
	- notify: When notify plugin is used and transaction commit fails in
	  dsync, crash occurs.
	- sdbox: When delivering to a mailbox that is over quota, temp files
	  are not cleaned up when saving or copying fails.

v2.2.34 2018-02-28  Timo Sirainen <tss@iki.fi>

	* CVE-2017-15130: TLS SNI config lookups may lead to excessive
	  memory usage, causing imap-login/pop3-login VSZ limit to be reached
	  and the process restarted. This happens only if Dovecot config has
	  local_name { } or local { } configuration blocks and attacker uses
	  randomly generated SNI servernames.
	* CVE-2017-14461: Parsing invalid email addresses may cause a crash or
	  leak memory contents to attacker. For example, these memory contents
	  might contain parts of an email from another user if the same imap
	  process is reused for multiple users. First discovered by Aleksandar
	  Nikolic of Cisco Talos. Independently also discovered by "flxflndy"
	  via HackerOne.
	* CVE-2017-15132: Aborted SASL authentication leaks memory in login
	  process.
	* Linux: Core dumping is no longer enabled by default via
	  PR_SET_DUMPABLE, because this may allow attackers to bypass
	  chroot/group restrictions. Found by cPanel Security Team. Nowadays
	  core dumps can be safely enabled by using "sysctl -w
	  fs.suid_dumpable=2". If the old behaviour is wanted, it can still be
	  enabled by setting:
	  import_environment=$import_environment PR_SET_DUMPABLE=1
	* doveconf output now includes the hostname.

	+ mail_attachment_detection_options setting controls when
	  $HasAttachment and $HasNoAttachment keywords are set for mails.
	+ imap: Support fetching body snippets using FETCH (SNIPPET) or
	  (SNIPPET (LAZY=FUZZY))
	+ fs-compress: Automatically detect whether input is compressed or not.
	  Prefix the compression algorithm with "maybe-" to enable the
	  detection, for example: "compress:maybe-gz:6:..."
	+ Added settings to change dovecot.index* files' optimization behavior.
	  See https://wiki2.dovecot.org/IndexFiles#Settings
	+ Auth cache can now utilize auth workers to do password hash
	  verification by setting auth_cache_verify_password_with_worker=yes.
	+ Added charset_alias plugin. See
	  https://wiki2.dovecot.org/Plugins/CharsetAlias
	+ imap_logout_format and pop3_logout_format settings now support all of
	  the generic variables (e.g. %{rip}, %{session}, etc.)
	+ Added auth_policy_check_before_auth, auth_policy_check_after_auth
	  and auth_policy_report_after_auth settings.
	- v2.2.33: doveadm-server: Various fixes related to log handling.
	- v2.2.33: doveadm failed when trying to access UNIX socket that didn't
	  require authentication.
	- v2.2.33: doveadm log reopen stopped working
	- v2.2.30+: IMAP stopped advertising SPECIAL-USE capability
	- v2.2.30+: IMAP stopped sending untagged OK/NO storage notifications
	- replication: dsync sends unnecessary replication notification for
