options, and new features, see the NewStuff file next to this ChangeLog.
+Exim version 4.92
+-----------------
+
+JH/01 Remove code calling the customisable local_scan function, unless a new
+ definition "HAVE_LOCAL_SCAN=yes" is present in the Local/Makefile.
+
+JH/02 Bug 1007: Avoid doing logging from signal-handlers, as that can result in
+ non-signal-safe functions being used.
+
+JH/03 Bug 2269: When presented with a received message having a stupidly large
+ number of DKIM-Signature headers, disable DKIM verification to avoid
+ a resource-consumption attack. The limit is set at twenty.
+
+JH/04 Add variables $arc_domains, $arc_oldest_pass for ARC verify. Fix the
+ report of oldest_pass in ${authres } in consequence, and separate out
+ some descriptions of reasons for verification fail.
+
+JH/05 Bug 2273: Cutthrough delivery left a window where the received messsage
+ files in the spool were present and unlocked. A queue-runner could spot
+ them, resulting in a duplicate delivery. Fix that by doing the unlock
+ after the unlink. Investigation by Tim Stewart. Take the opportunity to
+ add more error-checking on spoolfile handling while that code is being
+ messed with.
+
+PP/01 Refuse to open a spool data file (*-D) if it's a symlink.
+ No known attacks, no CVE, this is defensive hardening.
+
+JH/06 Bug 2275: The MIME ACL unlocked the received message files early, and
+ a queue-runner could start a delivery while other operations were ongoing.
+ Cutthrough delivery was a common victim, resulting in duplicate delivery.
+ Found and investigated by Tim Stewart. Fix by using the open message data
+ file handle rather than opening another, and not locally closing it (which
+ releases a lock) for that case, while creating the temporary .eml format
+ file for the MIME ACL. Also applies to "regex" and "spam" ACL conditions.
+
+JH/07 Bug 177: Make a random-recipient callout success visible in ACL, by setting
+ $sender_verify_failure/$recipient_verify_failure to "random".
+
+JH/08 When generating a selfsigned cert, use serial number 1 since zero is not
+ legitimate.
+
+JH/09 Bug 2274: Fix logging of cmdline args when starting in an unlinked cwd.
+ Previously this would segfault.
+
+JH/10 Fix ARC signing for case when DKIM signing failed. Previously this would
+ segfault.
+
+JH/11 Bug 2264: Exim now only follows CNAME chains one step by default. We'd
+ like zero, since the resolver should be doing this for us, But we need one
+ as a CNAME but no MX presence gets the CNAME returned; we need to check
+ that doesn't point to an MX to declare it "no MX returned" rather than
+ "error, loop". A new main option is added so the older capability of
+ following some limited number of chain links is maintained.
+
+JH/12 Add client-ip info to non-pass iprev ${authres } lines.
+
+JH/13 For receent Openssl versions (1.1 onward) use modern generic protocol
+ methods. These should support TLS 1.3; they arrived with TLS 1.3 and the
+ now-deprecated earlier definitions used only specified the range up to TLS
+ 1.2 (in the older-version library docs).
+
+JH/14 Bug 2284: Fix DKIM signing for body lines starting with a pair of dots.
+
+JH/15 Rework TLS client-side context management. Stop using a global, and
+ explicitly pass a context around. This enables future use of TLS for
+ connections to service-daemons (eg. malware scanning) while a client smtp
+ connection is using TLS; with cutthrough connections this is quite likely.
+
+JH/16 Fix ARC verification to do AS checks in reverse order.
+
+JH/17 Support a "tls" option on the ${readsocket } expansion item.
+
+JH/18 Bug 2287: Fix the protocol name (eg utf8esmtp) for multiple messages
+ using the SMTPUTF8 option on their MAIL FROM commands, in one connection.
+ Previously the "utf8" would be re-prepended for every additional message.
+
+JH/19 Reject MAIL FROM commands with SMTPUTF8 when the facility was not advertised.
+ Previously thery were accepted, resulting in issues when attempting to
+ forward messages to a non-supporting MTA.
+
+PP/02 Let -n work with printing macros too, not just options.
+
+JH/20 Bug 2296: Fix cutthrough for >1 address redirection. Previously only
+ one parent address was copied, and bogus data was used at delivery-logging
+ time. Either a crash (after delivery) or bogus log data could result.
+ Discovery and analysis by Tim Stewart.
+
+PP/03 Make ${utf8clean:} expansion operator detect incomplete final character.
+ Previously if the string ended mid-character, we did not insert the
+ promised '?' replacement.
+
+PP/04 Documentation: current string operators work on bytes, not codepoints.
+
+JH/21 Change as many as possible of the global flags into one-bit bitfields; these
+ should pack well giving a smaller memory footprint so better caching and
+ therefore performance. Group the declarations where this can't be done so
+ that the byte-sized flag variables are not interspersed among pointer
+ variables, giving a better chance of good packing by the compiler.
+
+JH/22 Bug 1896: Fix the envelope from for DMARC forensic reports to be possibly
+ non-null, to avoid issues with sites running BATV. Previously reports were
+ sent with an empty envelope sender so looked like bounces.
+
+JH/23 Bug 2318: Fix the noerror command within filters. It wasn't working.
+ The ignore_error flag wasn't being returned from the filter subprocess so
+ was not set for later routers. Investigation and fix by Matthias Kurz.
+
+JH/24 Bug 2310: Raise a msg:fail:internal event for each undelivered recipient,
+ and a msg:complete for the whole, when a message is manually removed using
+ -Mrm. Developement by Matthias Kurz, hacked on by JH.
+
+JH/25 Avoid fixed-size buffers for pathnames in DB access. This required using
+ a "Gnu special" function, asprintf() in the DB utility binary builds; I
+ hope that is portable enough.
+
+JH/26 Bug 2311: Fix DANE-TA verification under GnuTLS. Previously it was also
+ requiring a known-CA anchor certificate; make it now rely entirely on the
+ TLSA as an anchor. Checking the name on the leaf cert against the name
+ on the A-record for the host is still done for TA (but not for EE mode).
+
+JH/27 Fix logging of proxy address. Previously, a pointless "PRX=[]:0" would be
+ included in delivery lines for non-proxied connections, when compiled with
+ SUPPORT_SOCKS and running with proxy logging enabled.
+
+JH/28 Bug 2314: Fire msg:fail:delivery event even when error is being ignored.
+ Developement by Matthias Kurz, tweaked by JH. While in that bit of code,
+ move the existing event to fire before the normal logging of message
+ failure so that custom logging is bracketed by normal logging.
+
+JH/29 Bug 2322: A "fail" command in a non-system filter (file) now fires the
+ msg:fail:internal event. Developement by Matthias Kurz.
+
+JH/30 Bug 2329: Increase buffer size used for dns lookup from 2k, which was
+ far too small for todays use of crypto signatures stored there. Go all
+ the way to the max DNS message size of 64kB, even though this might be
+ overmuch for IOT constrained device use.
+
+JH/31 Fix a bad use of a copy function, which could be used to pointlessly
+ copy a string over itself. The library routine is documented as not
+ supporting overlapping copies, and on MacOS it actually raised a SIGABRT.
+
+JH/32 For main options check_spool_space and check_inode_space, where the
+ platform supports 64b integers, support more than the previous 2^31 kB
+ (i.e. more than 2 TB). Accept E, P and T multipliers in addition to
+ the previous G, M, k.
+
+JH/33 Bug 2338: Fix the cyrus-sasl authenticator to fill in the
+ $authenticated_fail_id variable on authentication failure. Previously
+ it was unset.
+
+JH/34 Increase RSA keysize of autogen selfsign cert from 1024 to 2048. RHEL 8.0
+ OpenSSL didn't want to use such a weak key. Do for GnuTLS also, and for
+ more-modern GnuTLS move from GNUTLS_SEC_PARAM_LOW to
+ GNUTLS_SEC_PARAM_MEDIUM.
+
+JH/35 OpenSSL: fail the handshake when SNI processing hits a problem, server
+ side. Previously we would continue as if no SNI had been received.
+
+JH/36 Harden the handling of string-lists. When a list consisted of a sole
+ "<" character, which should be a list-separator specification, we walked
+ off past the nul-terimation.
+
+JH/37 Bug 2341: Send "message delayed" warning MDNs (restricted to external
+ causes) even when the retry time is not yet met. Previously they were
+ not, meaning that when (say) an account was over-quota and temp-rejecting,
+ and multiple senders' messages were queued, only one sender would get
+ notified on each configured delay_warning cycle.
+
+JH/38 Bug 2351: Log failures to extract envelope addresses from message headers.
+
+
Exim version 4.91
-----------------
+GF/01 DEFER rather than ERROR on redis cluster MOVED response.
+ When redis_servers is set to a list of > 1 element, and the Redis servers
+ in that list are in cluster configuration, convert the REDIS_REPLY_ERROR
+ case of MOVED into a DEFER case instead, thus moving the query onto the
+ next server in the list. For a cluster of N elements, all N servers must
+ be defined in redis_servers.
+
+GF/02 Catch and remove uninitialized value warning in exiqsumm
+ Check for existence of @ARGV before looking at $ARGV[0]
+
JH/01 Replace the store_release() internal interface with store_newblock(),
which internalises the check required to safely use the old one, plus
the allocate and data copy operations duplicated in both (!) of the
ignoring. This covers use with PRDR, frozen messages, queue-only and
fake-reject.
+HS/01 Fix Buffer overflow in base64d() (CVE-2018-6789)
+
+JH/16 Fix bug in DKIM verify: a buffer overflow could corrupt the malloc
+ metadata, resulting in a crash in free().
+
+PP/01 Fix broken Heimdal GSSAPI authenticator integration.
+ Broken in f2ed27cf5, missing an equals sign for specified-initialisers.
+ Broken also in d185889f4, with init system revamp.
+
+JH/17 Bug 2113: Fix conversation closedown with the Avast malware scanner.
+ Previously we abruptly closed the connection after reading a malware-
+ found indication; now we go on to read the "scan ok" response line,
+ and send a quit.
+
+JH/18 Bug 2239: Enforce non-usability of control=utf8_downconvert in the mail
+ ACL. Previously, a crash would result.
+
+JH/19 Speed up macro lookups during configuration file read, by skipping non-
+ macro text after a replacement (previously it was only once per line) and
+ by skipping builtin macros when searching for an uppercase lead character.
+
+JH/20 DANE support moved from Experimental to mainline. The Makefile control
+ for the build is renamed.
+
+JH/21 Fix memory leak during multi-message connections using STARTTLS. A buffer
+ was allocated for every new TLS startup, meaning one per message. Fix
+ by only allocating once (OpenSSL) or freeing on TLS-close (GnuTLS).
+
+JH/22 Bug 2236: When a DKIM verification result is overridden by ACL, DMARC
+ reported the original. Fix to report (as far as possible) the ACL
+ result replacing the original.
+
+JH/23 Fix memory leak during multi-message connections using STARTTLS under
+ OpenSSL. Certificate information is loaded for every new TLS startup,
+ and the resources needed to be freed.
+
+JH/24 Bug 2242: Fix exim_dbmbuild to permit directoryless filenames.
+
+JH/25 Fix utf8_downconvert propagation through a redirect router. Previously it
+ was not propagated.
+
+JH/26 Bug 2253: For logging delivery lines under PRDR, append the overall
+ DATA response info to the (existing) per-recipient response info for
+ the "C=" log element. It can have useful tracking info from the
+ destination system. Patch from Simon Arlott.
+
+JH/27 Bug 2251: Fix ldap lookups that return a single attribute having zero-
+ length value. Previously this would segfault.
+
+HS/02 Support Avast multiline protoocol, this allows passing flags to
+ newer versions of the scanner.
+
+JH/28 Ensure that variables possibly set during message acceptance are marked
+ dead before release of memory in the daemon loop. This stops complaints
+ about them when the debug_store option is enabled. Discovered specifically
+ for sender_rate_period, but applies to a whole set of variables.
+ Do the same for the queue-runner and queue-list loops, for variables set
+ from spool message files. Do the same for the SMTP per-message loop, for
+ certain variables indirectly set in ACL operations.
+
+JH/29 Bug 2250: Fix a longstanding bug in heavily-pipelined SMTP input (such
+ as a multi-recipient message from a mailinglist manager). The coding had
+ an arbitrary cutoff number of characters while checking for more input;
+ enforced by writing a NUL into the buffer. This corrupted long / fast
+ input. The problem was exposed more widely when more pipelineing of SMTP
+ responses was introduced, and one Exim system was feeding another.
+ The symptom is log complaints of SMTP syntax error (NUL chars) on the
+ receiving system, and refused recipients seen by the sending system
+ (propating to people being dropped from mailing lists).
+ Discovered and pinpointed by David Carter.
+
+JH/30 The (EXPERIMENTAL_DMARC) variable $dmarc_ar_header is withdrawn, being
+ replaced by the ${authresults } expansion.
+
+JH/31 Bug 2257: Fix pipe transport to not use a socket-only syscall.
+
+HS/03 Set a handler for SIGTERM and call exit(3) if running as PID 1. This
+ allows proper process termination in container environments.
+
+JH/32 Bug 2258: Fix spool_wireformat in combination with LMTP transport.
+ Previously the "final dot" had a newline after it; ensure it is CR,LF.
+
+JH/33 SPF: remove support for the "spf" ACL condition outcome values "err_temp"
+ and "err_perm", deprecated since 4.83 when the RFC-defined words
+ "temperror" and "permerror" were introduced.
+
+JH/34 Re-introduce enforcement of no cutthrough delivery on transports having
+ transport-filters or DKIM-signing. The restriction was lost in the
+ consolidation of verify-callout and delivery SMTP handling.
+ Extend the restriction to also cover ARC-signing.
+
+JH/35 Cutthrough: for a final-dot response timeout (and nonunderstood responses)
+ in defer=pass mode supply a 450 to the initiator. Previously the message
+ would be spooled.
+
+PP/02 DANE: add dane_require_tls_ciphers SMTP Transport option; if unset,
+ tls_require_ciphers is used as before.
+
+HS/03 Malware Avast: Better match the Avast multiline protocol. Add
+ "pass_unscanned". Only tmpfails from the scanner are written to
+ the paniclog, as they may require admin intervention (permission
+ denied, license issues). Other scanner errors (like decompression
+ bombs) do not cause a paniclog entry.
+
+JH/36 Fix reinitialisation of DKIM logging variable between messages.
+ Previously it was possible to log spurious information in receive log
+ lines.
+
+JH/37 Bug 2255: Revert the disable of the OpenSSL session caching. This
+ triggered odd behaviour from Outlook Express clients.
+
+PP/03 Add util/renew-opendmarc-tlds.sh script for safe renewal of public
+ suffix list.
+
+JH/38 DKIM: accept Ed25519 pubkeys in SubjectPublicKeyInfo-wrapped form,
+ since the IETF WG has not yet settled on that versus the original
+ "bare" representation.
+
+JH/39 Fix syslog logging for syslog_timestamp=no and log_selector +millisec.
+ Previously the millisecond value corrupted the output.
+ Fix also for syslog_pid=no and log_selector +pid, for which the pid
+ corrupted the output.
+
Exim version 4.90
-----------------
line, the header hash was calculated to an incorrect value thanks to
the (relaxed) space the fold became.
-HS/02 Fix Bug 2130: large writes from the transport subprocess where chunked
+HS/02 Fix Bug 2130: large writes from the transport subprocess were chunked
and confused the parent.
JH/27 Fix SOCKS bug: an unitialized pointer was deref'd by the transport process