options, and new features, see the NewStuff file next to this ChangeLog.
-Since Exim version 4.90
------------------------
+Exim version 4.93
+-----------------
+
+JH/01 OpenSSL: With debug enabled output keying information sufficient, server
+ side, to decode a TLS 1.3 packet capture.
+
+JH/02 OpenSSL: suppress the sending of (stateful) TLS1.3 session tickets.
+ Previously the default library behaviour applied, sending two, each in
+ its own TCP segment.
+
+JH/03 Debug output for ACL now gives the config file name and line number for
+ each verb.
+
+JH/04 The default received_header_text now uses the RFC 8314 tls cipher clause.
+
+JH/05 DKIM: ensure that dkim_domain elements are lowercased before use.
+
+
+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.
+
+JH/39 OpenSSL: clear the error stack after an SSL_accept(). With anon-auth
+ cipher-suites, an error can be left on the stack even for a succeeding
+ accept; this results in impossible error messages when a later operation
+ actually does fail.
+
+AM/01 Bug 2359: GnuTLS: repeat lowlevel read and write operations while they
+ return error codes indicating retry. Under TLS1.3 this becomes required.
+
+JH/40 Fix the feature-cache refresh for EXPERIMENTAL_PIPE_CONNECT. Previously
+ it only wrote the new authenticators, resulting in a lack of tracking of
+ peer changes of ESMTP extensions until the next cache flush.
+
+JH/41 Fix the loop reading a message header line to check for integer overflow,
+ and more-often against header_maxsize. Previously a crafted message could
+ induce a crash of the recive process; now the message is cleanly rejected.
+
+JH/42 Bug 2366: Fix the behaviour of the dkim_verify_signers option. It had
+ been totally disabled for all of 4.91. Discovery and fix by "Mad Alex".
+
+
+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
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