+Exim version 4.97
+-----------------
+
+JH/01 The hosts_connection_nolog main option now also controls "no MAIL in
+ SMTP connection" log lines.
+
+JH/02 Option default value updates:
+ - queue_fast_ramp (main) true (was false)
+ - remote_max_parallel (main) 4 (was 2)
+
+JH/03 Cache static regex pattern compilations, for use by ACLs.
+
+Exim version 4.96
+-----------------
+
+JH/01 Move the wait-for-next-tick (needed for unique messmage IDs) from
+ after reception to before a subsequent reception. This should
+ mean slightly faster delivery, and also confirmation of reception
+ to senders.
+
+JH/02 Move from using the pcre library to pcre2. The former is no longer
+ being developed or supported (by the original developer).
+
+JH/03 Constification work in the filters module required a major version
+ bump for the local-scan API. Specifically, the "headers_charset"
+ global which is visible via the API is now const and may therefore
+ not be modified by local-scan code.
+
+JH/04 Fix ClamAV TCP use under FreeBSD. Previously the OS-specific shim for
+ sendfile() didi not account for the way the ClamAV driver code called it.
+
+JH/05 Bug 2819: speed up command-line messages being read in. Previously a
+ time check was being done for every character; replace that with one
+ per buffer.
+
+JH/06 Bug 2815: Fix ALPN sent by server under OpenSSL. Previously the string
+ sent was prefixed with a length byte.
+
+JH/07 Change the SMTP feature name for pipelining connect to be compliant with
+ RFC 5321. Previously Dovecot (at least) would log errors during
+ submission.
+
+JH/08 Remove stripping of the binaries from the FreeBSD build. This was added
+ in 4.61 without a reason logged. Binaries will be bigger, which might
+ matter on diskspace-constrained systems, but debug is easier.
+
+JH/09 Fix macro-definition during "-be" expansion testing. The move to
+ write-protected store for macros had not accounted for these runtime
+ additions; fix by removing this protection for "-be" mode.
+
+JH/10 Convert all uses of select() to poll(). FreeBSD 12.2 was found to be
+ handing out large-numbered file descriptors, violating the usual Unix
+ assumption (and required by Posix) that the lowest possible number will be
+ allocated by the kernel when a new one is needed. In the daemon, and any
+ child procesees, values higher than 1024 (being bigger than FD_SETSIZE)
+ are not useable for FD_SET() [and hence select()] and overwrite the stack.
+ Assorted crashes happen.
+
+JH/11 Fix use of $sender_host_name in daemon process. When used in certain
+ main-section options or in a connect ACL, the value from the first ever
+ connection was never replaced for subsequent connections. Found by
+ Wakko Warner.
+
+JH/12 Bug 2838: Fix for i32lp64 hard-align platforms. Found for SPARC Linux,
+ though only once PCRE2 was introduced: the memory accounting used under
+ debug offset allocations by an int, giving a hard trap in early startup.
+ Change to using a size_t. Debug and fix by John Paul Adrian Glaubitz.
+
+JH/13 Bug 2845: Fix handling of tls_require_ciphers for OpenSSL when a value
+ with underbars is given. The write-protection of configuration introduced
+ in 4.95 trapped when normalisation was applied to an option not needing
+ expansion action.
+
+JH/14 Bug 1895: TLS: Deprecate RFC 5114 Diffie-Hellman parameters.
+
+JH/15 Fix a resource leak in *BSD. An off-by-one error resulted in the daemon
+ failing to close the certificates directory, every hour or any time it
+ was touched.
+
+JH/16 Debugging initiated by an ACL control now continues through into routing
+ and transport processes. Previously debugging stopped any time Exim
+ re-execs, or for processing a queued message.
+
+JH/17 The "expand" debug selector now gives more detail, specifically on the
+ result of expansion operators and items.
+
+JH/18 Bug 2751: Fix include_directory in redirect routers. Previously a
+ bad comparison between the option value and the name of the file to
+ be included was done, and a mismatch was wrongly identified.
+ 4.88 to 4.95 are affected.
+
+JH/19 Support for Berkeley DB versions 1 and 2 is withdrawn.
+
+JH/20 When built with NDBM for hints DB's check for nonexistence of a name
+ supplied as the db file-pair basename. Previously, if a directory
+ path was given, for example via the autoreply "once" option, the DB
+ file.pag and file.dir files would be created in that directory's
+ parent.
+
+JH/21 Remove the "allow_insecure_tainted_data" main config option and the
+ "taint" log_selector. These were previously deprecated.
+
+JH/22 Fix static address-list lookups to properly return the matched item.
+ Previously only the domain part was returned.
+
+JH/23 Bug 2864: FreeBSD: fix transport hang after 4xx/5xx response. Previously
+ the call into OpenSSL to send a TLS Close was being repeated; this
+ resulted in the library waiting for the peer's Close. If that was never
+ sent we waited forever. Fix by tracking send calls.
+
+JH/24 The ${run} expansion item now expands its command string elements after
+ splitting. Previously it was before; the new ordering makes handling
+ zero-length arguments simpler. The old ordering can be obtained by
+ appending a new option "preexpand", after a comma, to the "run".
+
+JH/25 Taint-check exec arguments for transport-initiated external processes.
+ Previously, tainted values could be used. This affects "pipe", "lmtp" and
+ "queryprogram" transport, transport-filter, and ETRN commands.
+ The ${run} expansion is also affected: in "preexpand" mode no part of
+ the command line may be tainted, in default mode the executable name
+ may not be tainted.
+
+JH/26 Fix CHUNKING on a continued-transport. Previously the usabliility of
+ the the facility was not passed across execs, and only the first message
+ passed over a connection could use BDAT; any further ones using DATA.
+
+JH/27 Support the PIPECONNECT facility in the smtp transport when the helo_data
+ uses $sending_ip_address and an interface is specified.
+ Previously any use of the local address in the EHLO name disabled
+ PIPECONNECT, the common case being to use the rDNS of it.
+
+JH/28 OpenSSL: fix transport-required OCSP stapling verification under session
+ resumption. Previously verify failed because no certificate status is
+ passed on the wire for the restarted session. Fix by using the recorded
+ ocsp status of the stored session for the new connection.
+
+JH/29 TLS resumption: the key for session lookup in the client now includes
+ more info that a server could potentially use in configuring a TLS
+ session, avoiding oferring mismatching sessions to such a server.
+ Previously only the server IP was used.
+
+JH/30 Fix string_copyn() for limit greater than actual string length.
+ Previously the copied amount was the limit, which could result in a
+ overlapping memcpy for newly allocated destination soon after a
+ source string shorter than the limit. Found/investigated by KM.
+
+JH/31 Bug 2886: GnuTLS: Do not free the cached creds on transport connection
+ close; it may be needed for a subsequent connection. This caused a
+ SEGV on primary-MX defer. Found/investigated by Gedalya & Andreas.
+
+JH/32 Fix CHUNKING for a second message on a connection when the first was
+ rejected. Previously we did not reset the chunking-offered state, and
+ erroneously rejected the BDAT command. Investigation help from
+ Jesse Hathaway.
+
+JH/33 Fis ${srs_encode ...} to handle an empty sender address, now returning
+ an empty address. Previously the expansion returned an error.
+
+HS/01 Bug 2855: Handle a v4mapped sender address given us by a frontending
+ proxy. Previously these were misparsed, leading to paniclog entries.
+
+
+Exim version 4.95
+-----------------
+
+JH/01 Bug 1329: Fix format of Maildir-format filenames to match other mail-
+ related applications. Previously an "H" was used where available info
+ says that "M" should be, so change to match.
+
+JH/02 Bug 2587: Fix pam expansion condition. Tainted values are commonly used
+ as arguments, so an implementation trying to copy these into a local
+ buffer was taking a taint-enforcement trap. Fix by using dynamically
+ created buffers. Similar fix for radius expansion condition.
+
+JH/03 Bug 2586: Fix listcount expansion operator. Using tainted arguments is
+ reasonable, eg. to count headers. Fix by using dynamically created
+ buffers rather than a local. Do similar fixes for ACL actions "dcc",
+ "log_reject_target", "malware" and "spam"; the arguments are expanded
+ so could be handling tainted values.
+
+JH/04 Bug 2590: Fix -bi (newaliases). A previous code rearrangement had
+ broken the (no-op) support for this sendmail command. Restore it
+ to doing nothing, silently, and returning good status.
+
+JH/05 Bug 2593: Fix "vacation" in Exim filter. Previously, when a "once"
+ record path was given (or the default used) without a leading directory
+ path, an error occurred on trying to open it. Use the transport's working
+ directory.
+
+JH/06 Bug 2594: Change the name used for certificate name checks in the smtp
+ transport. Previously it was the name on the DNS A-record; use instead
+ the head of the CNAME chain leading there (if there is one). This seems
+ to align better with RFC 6125.
+
+JH/07 Bug 2597: Fix a resource leak. Using a lookup in obtaining a value for
+ smtp_accept_max_per_host allocated resources which were not released
+ when the limit was exceeded. This eventually crashed the daemon. Fix
+ by adding a release action in that path.
+
+JH/08 Bug 2598: Fix verify ACL condition. The options for the condition are
+ expanded; previously using tainted values was rejected. Fix by using
+ dynamically-created buffers.
+
+JH/09 Relax restrictions on ACL verify condition needing access to message
+ headers. Previously they were only permitted in data and non-smtp ACLs;
+ permit also mime, dkim, prdr quit and notquit. Applies to header-syntax,
+ not_blind, header_sender and header_names_ascii verification.
+
+JH/10 Bug 2603: Fix coding of string copying to only evaluate arguments once.
+ Previously a macro used one argument twice; when called with the
+ argument as an expression having side-effects, incorrect operation
+ resulted. Use an inlineable function.
+
+JH/11 Bug 2604: Fix request to cutthrough-deliver when a connection is already
+ held open for a verify callout. Previously this wan not accounted for
+ and a corrupt onward SMTP conversation resulted.
+
+JH/12 Bug 2607: Fix the ${srs_encode } expansion to handle quoted local_parts.
+ Previously they were embedded naively in the constructed address; when
+ needed, strip the quoting and quote the entire local_part.
+ Also make the inbound_srs expansion condition handle quoting.
+
+JH/13 Fix dsearch "subdir" filter to ignore ".". Previously only ".." was
+ excluded, not matching the documentation.
+
+JH/14 Bug 2606: Fix a segfault in sqlite lookups. When no, or a bad, filename
+ was given for the sqlite_dbfile a trap resulted.
+
+JH/15 Bug 2620: Fix "spam" ACL condition. Previously, tainted values for the
+ "name" argument resulted in a trap. There is no reason to disallow such;
+ this was a coding error.
+
+JH/16 Bug 2615: Fix pause during message reception, on systems that have been
+ suspended/resumed. The Linux CLOCK_MONOTONIC does not account for time
+ spent suspended, ignoring the POSIX definition. Previously we assumed
+ it did and a constant offset from real time could be used as a correction.
+ Change to using the same clock source for the start-of-message and the
+ post-message next-tick-wait. Also change to using CLOCK_BOOTTIME if it
+ exists, just to get a clock slightly more aligned to reality.
+
+JH/17 Bug 2295: Fix DKIM signing to always semicolon-terminate. Although the
+ RFC says it is optional some validators care. The missing char was not
+ intended but triggered by a line-wrap alignment. Discovery and fix by
+ Guillaume Outters, hacked on by JH.
+
+JH/18 Bug 2617: Fix a taint trap in parse_fix_phrase(). Previously when the
+ name being quoted was tainted a trap would be taken. Fix by using
+ dynamically created buffers. The routine could have been called by a
+ rewrite with the "h" flag, by using the "-F" command-line option, or
+ by using a "name=" option on a control=submission ACL modifier.
+
+JH/19 SPF: change the Authentication-Results expansion component to give
+ smtp.helo when the sender domain is empty. Previously it gave
+ "smtp.mailfrom=<>"
+
+JH/20 Bug 2631: ACL dnslist conditions now ignore and log any lookups returns
+ not in 127.0.0.0/8 to help in spotting list domains taken over by a
+ domain-parking registrar.
+
+JH/21 Bug 2630: Fix eol-replacement string for the ${readsocket } expansion.
+ Previously when a whitespace character was specified it was not inserted
+ after removing the newline.
+
+JH/22 Bug 2265: Force SNI usage for smtp transport DANE'd connections, to be
+ the domain part of the recipient address. This overrides any tls_sni
+ option set, which was previously used.
+
+JH/23 Logging: with the +tls_sni log_selector, do not wrap the received SNI
+ in quotes.
+
+JH/24 Bug 2634: Fix a taint trap seen on NetBSD: the testing coded for
+ is_tainted() had an off-by-one error in the overenthusiastic direction.
+ Find and fix by Gavan. Although NetBSD is not a supported platform for
+ 4.94 this bug could affect other platforms.
+
+PP/01 Fix default prime selection to be consistent.
+ One path used ike23 still, instead of exim.dev.20160529.3; now both
+ execution flows will use the same DH primes (currently
+ exim.dev.20160529.3).
+
+JH/25 OpenSSL: Fix back-compatibility behaviour surrounding tls_certificates
+ option in smtp transport, to match the documentation. Previously
+ verification was not being done in some cases where it should have been.
+
+JH/26 Bug 2646: fix a memory usage issue in ldap lookups. Previously, when more
+ than one server was defined and depending on the platform memory layout
+ details, an internal consistency trap could be hit while walking the list
+ of servers.
+
+JH/27 Bug 2648: fix the passing of an authenticator public-name through spool
+ files. The value is used by the authresults expansion item. Previously
+ if this was used in a router or transport, a crash could result.
+
+JH/28 Fix spurious logging of select error. Some platforms, notably FreeBSD,
+ have a sufficient incidence of EINTR returns from select that an
+ interaction with other operations done by the main daemon loop exposed
+ a bug in the error-handling. This was benign apart from the log
+ messages.
+
+JH/29 Bug 2675: add outgoing-interface I= element to deferred "==" log lines,
+ for consistency with delivered "=>" and failed "**" lines. While we're
+ there, handle PRX and TFO.
+
+JH/30 Bug 2677: fix matching of long addresses. Since 4.93 a limit of 256 was
+ applied. This resulted, if any header-line rewrite rules were configured,
+ in a panic-log triggerable by sending a message with a long address in
+ a header. Fix by increasing the arbitrary limit to larger than a single
+ (dewrapped) 5322 header line maximum size.
+
+JH/31 The ESMTP option name advertised for the SUPPORT_EARLY_PIPE build option
+ is changed from X_PIPE_CONNECT to PIPE_CONNECT. This is in line with
+ RFC 6648 which deprecates X- options in protocols as a general practice.
+ Changeover between the implementations is handled by the mechanisms
+ already coded.
+
+JH/32 Bug 2599: fix delay of delivery to a local address where there is also
+ a remote which uses callout/hold. Previously the local was queued.
+
+JH/33 Fix a taint trap in the ${listextract } expansion when the source data
+ was tainted.
+
+JH/34 Fix the placement of a multiple-message delivery marker in the delivery
+ log line. The asterisk is now consistently appended to the remote IP
+ (and port, if given), and will also be provided on defer and fail log
+ lines. Previously it could be placed on the local IP if that was being
+ logged, and was only provided on delivery lines.
+
+JH/35 Bug 2343: Harden exim_tidydb against corrupt wait- files.
+
+JH/36 Bug 2687: Fix interpretation of multiple ^ chars in a plaintext
+ authenticator client_send option. Previously the next char, after a pair
+ was collapsed, was taken verbatim (so ^^^foo became ^^foo; ^^^^foo became
+ ^^\x00foo). Fixed to get ^\x00foo and ^^foo respectively to match the
+ documentation. There is still no way to get a leading ^ immediately
+ after a NUL (ie. for the password of a PLAIN method authenticator.
+
+JH/37 Enforce the expected size, for fixed-size records read from hints-DB
+ files. For bad sizes read, delete the record and whine to paniclog.
+
+JH/38 When logging an AUTH failure, as server, do not include sensitive
+ information. Previously, the credentials would be included if given
+ as part of the AUTH command line and an ACL denied authentication.
+
+JH/39 Bug 2691: fix $local_part_data. When the matching list element
+ referred to a file, bad data was returned. This likely also affected
+ $domain_part_data.
+
+JH/40 The gsasl authenticator now supports caching of the salted password
+ generated by the client-side implementation. This required the addition
+ of a new variable: $auth4.
+
+JH/41 Fix daemon SIGHUP on FreeBSD. Previously, a named socket for IPC was
+ left undeleted; the attempt to re-create it then failed - resulting in
+ the usual "SIGHUP tp have daemon reload configuration" to not work.
+ This affected any platform not supporting "abstract" Unix-domain
+ sockets (i.e. not Linux).
+
+JH/42 Bug 2693: Harden against a peer which reneges on a 452 "too many
+ recipients" response to RCPT in a later response, with a 250. The
+ previous coding assumed this would not happen, and under PIPELINING
+ would result in both lost and duplicate recipients for a message.
+
+JH/43 Bug 2694: Fix weighted distribution of work to multiple spamd servers.
+ Previously the weighting was incorrectly applied. Similar fix for socks
+ proxies. Found and fixed by Heiko Schlichting.
+
+JH/44 Bug 2701: Fix list-expansion of dns_ipv4_lookup. Previously, it did
+ not handle sub-lists included using the +namedlist syntax. While
+ investigating, the same found for dns_trust_aa, dns_again_means_nonexist,
+ dnssec_require_domains, dnssec_request_domains, srv_fail_domains,
+ mx_fail_domains.
+
+JH/45 Use a (new) separate store pool-pair for DKIM verify working data.
+ Previously the permanent pool was used, so the sore could not be freed.
+ This meant a connection with many messages would use continually-growing
+ memory.
+
+JH/46 Use an exponentially-increasing block size when malloc'ing store. Do it
+ per-pool so as not to waste too much space. Previously a constant size
+ was used which resulted in O(n^2) behaviour; now we get O(n log n) making
+ DOS attacks harder. The cost is wasted memory use in the larger blocks.
+
+JH/47 Use explicit alloc/free for DNS lookup workspace. This permits using the
+ same space repeatedly, and a smaller process footprint.
+
+JH/48 Use a less bogus-looking filename for a temporary used for DH-parameters
+ for GnuTLS. Previously the name started "%s" which, while not a bug,
+ looked as if if might be one.
+
+JH/49 Bug 2710: when using SOCKS for additional messages after the first (a
+ "continued connection") make the $proxy_* variables available. Previously
+ the information was not passed across the exec() call for subsequent
+ transport executions. This also mean that the log lines for the
+ messages can show the proxy information.
+
+JH/50 Bug 2672: QT elements in log lines, unless disabled, now exclude the
+ receive time. With modern systems the difference is significant.
+ The historical behaviour can be restored by disabling (a new) log_selector
+ "queue_time_exclusive".
+
+JH/51 Taint-check ACL line. Previously, only filenames (for out-of-line ACL
+ content) were specifically tested for. Now, also cover expansions
+ resulting in ACL names and inline ACL content.
+
+JH/52 Fix ${ip6norm:} operator. Previously, any trailing line text was dropped,
+ making it unusable in complex expressions.
+
+JH/53 Bug 2743: fix immediate-delivery via named queue. Previously this would
+ fail with a taint-check on the spoolfile name, and leave the message
+ queued.
+
+HS/01 Enforce absolute PID file path name.
+
+HS/02 Handle SIGINT as we handle SIGTERM: terminate the Exim process.
+
+PP/01 Add a too-many-bad-recipients guard to the default config's RCPT ACL.
+
+PP/02 Bug 2643: Correct TLS DH constants.
+ A missing NUL termination in our code-generation tool had led to some
+ incorrect Diffie-Hellman constants in the Exim source.
+ Reported by kylon94, code-gen tool fix by Simon Arlott.
+
+PP/03 Impose security length checks on various command-line options.
+ Fixes CVE-2020-SPRSS reported by Qualys.
+
+PP/04 Fix Linux security issue CVE-2020-SLCWD and guard against PATH_MAX
+ better. Reported by Qualys.
+
+PP/05 Fix security issue CVE-2020-PFPSN and guard against cmdline invoker
+ providing a particularly obnoxious sender full name.
+ Reported by Qualys.
+
+PP/06 Fix CVE-2020-28016 (PFPZA): Heap out-of-bounds write in parse_fix_phrase()
+
+PP/07 Refuse to allocate too little memory, block negative/zero allocations.
+ Security guard.
+
+PP/08 Change default for recipients_max from unlimited to 50,000.
+
+PP/09 Fix security issue with too many recipients on a message (to remove a
+ known security problem if someone does set recipients_max to unlimited,
+ or if local additions add to the recipient list).
+ Fixes CVE-2020-RCPTL reported by Qualys.
+
+PP/10 Fix security issue in SMTP verb option parsing
+ Fixes CVE-2020-EXOPT reported by Qualys.
+
+PP/11 Fix security issue in BDAT state confusion.
+ Ensure we reset known-good where we know we need to not be reading BDAT
+ data, as a general case fix, and move the places where we switch to BDAT
+ mode until after various protocol state checks.
+ Fixes CVE-2020-BDATA reported by Qualys.
+
+HS/03 Die on "/../" in msglog file names
+
+QS/01 Creation of (database) files in $spool_dir: only uid=0 or the uid of
+ the Exim runtime user are allowed to create files.
+
+QS/02 PID file creation/deletion: only possible if uid=0 or uid is the Exim
+ runtime user.
+
+QS/03 When reading the output from interpreted forward files we do not
+ pass the pipe between the parent and the interpreting process to
+ executed child processes (if any).
+
+QS/04 Always die if requested from internal logging, even is logging is
+ disabled.
+
+JH/54 DMARC: recent versions of the OpenDMARC library appear to have broken
+ the API; compilation noo longer completes with DMARC support included.
+ This affects 1.4.1-1 on Fedora 33 (1.3.2-3 is functional); and has
+ been reported on other platforms.
+
+JH/55 TLS: as server, reject connections with ALPN indicating non-smtp use.
+
+JH/56 Make the majority of info read from config files readonly, for defence-in-
+ depth against exploits. Suggestion by Qualys.
+ Not supported on Solaris 10.
+
+JH/57 Fix control=fakreject for a custom message containing tainted data.
+ Previously this resulted in a log complaint, due to a re-expansion present
+ since fakereject was originally introduced.
+
+JH/58 GnuTLS: Fix certextract expansion. If a second modifier after a tag
+ modifier was given, a loop resulted.
+
+JH/59 DKIM: Fix small-message verification under TLS with chunking. If a
+ pipelined SMTP command followed the BDAT LAST then it would be
+ incorrectly treated as part of the message body, causing a verification
+ fail.
+
+JH/60 Bug 2805: Fix logging of domain-literals in Message_ID: headers. They
+ require looser validation rules than those for 821-level addresses,
+ which only permit IP addresses.
+
+
+Exim version 4.94
+-----------------
+
+JH/01 Avoid costly startup code when not strictly needed. This reduces time
+ for some exim process initialisations. It does mean that the logging
+ of TLS configuration problems is only done for the daemon startup.
+
+JH/02 Early-pipelining support code is now included unless disabled in Makefile.
+
+JH/03 DKIM verification defaults no long accept sha1 hashes, to conform to
+ RFC 8301. They can still be enabled, using the dkim_verify_hashes main
+ option.
+
+JH/04 Support CHUNKING from an smtp transport using a transport_filter, when
+ DKIM signing is being done. Previously a transport_filter would always
+ disable CHUNKING, falling back to traditional DATA.
+
+JH/05 Regard command-line recipients as tainted.
+
+JH/06 Bug 340: Remove the daemon pid file on exit, when due to SIGTERM.
+
+JH/07 Bug 2489: Fix crash in the "pam" expansion condition. It seems that the
+ PAM library frees one of the arguments given to it, despite the
+ documentation. Therefore a plain malloc must be used.
+
+JH/08 Bug 2491: Use tainted buffers for the transport smtp context. Previously
+ on-stack buffers were used, resulting in a taint trap when DSN information
+ copied from a received message was written into the buffer.
+
+JH/09 Bug 2493: Harden ARC verify against Outlook, whick has been seen to mix
+ the ordering of its ARC headers. This caused a crash.
+
+JH/10 Bug 2492: Use tainted memory for retry record when needed. Previously when
+ a new record was being constructed with information from the peer, a trap
+ was taken.
+
+JH/11 Bug 2494: Unset the default for dmarc_tld_file. Previously a naiive
+ installation would get error messages from DMARC verify, when it hit the
+ nonexistent file indicated by the default. Distros wanting DMARC enabled
+ should both provide the file and set the option.
+ Also enforce no DMARC verification for command-line sourced messages.
+
+JH/12 Fix an uninitialised flag in early-pipelining. Previously connections
+ could, depending on the platform, hang at the STARTTLS response.
+
+JH/13 Bug 2498: Reset a counter used for ARC verify before handling another
+ message on a connection. Previously if one message had ARC headers and
+ the following one did not, a crash could result when adding an
+ Authentication-Results: header.
+
+JH/14 Bug 2500: Rewind some of the common-coding in string handling between the
+ Exim main code and Exim-related utities. The introduction of taint
+ tracking also did many adjustments to string handling. Since then, eximon
+ frequently terminated with an assert failure.
+
+JH/15 When PIPELINING, synch after every hundred or so RCPT commands sent and
+ check for 452 responses. This slightly helps the inefficieny of doing
+ a large alias-expansion into a recipient-limited target. The max_rcpt
+ transport option still applies (and at the current default, will override
+ the new feature). The check is done for either cause of synch, and forces
+ a fast-retry of all 452'd recipients using a new MAIL FROM on the same
+ connection. The new facility is not tunable at this time.
+
+JH/16 Fix the variables set by the gsasl authenticator. Previously a pointer to
+ library live data was being used, so the results became garbage. Make
+ copies while it is still usable.
+
+JH/17 Logging: when the deliver_time selector ise set, include the DT= field
+ on delivery deferred (==) and failed (**) lines (if a delivery was
+ attemtped). Previously it was only on completion (=>) lines.
+
+JH/18 Authentication: the gsasl driver not provides the $authN variables in time
+ for the expansion of the server_scram_iter and server_scram_salt options.
+
+WB/01 SPF: DNS lookups for the obsolete SPF RR type done by the libspf2 library
+ are now specifically given a NO_DATA response without hitting the system
+ resolver. The library goes on to do the now-standard TXT lookup.
+ Use of dnsdb lookups is not affected.
+
+JH/19 Bug 2507: Modules: on handling a dynamic-module (lookups) open failure,
+ only retrieve the errormessage once. Previously two calls to dlerror()
+ were used, and the second one (for mainlog/paniclog) retrieved null
+ information.
+
+JH/20 Taint checking: disallow use of tainted data for
+ - the appendfile transport file and directory options
+ - the pipe transport command
+ - the autoreply transport file, log and once options
+ - file names used by the redirect router (including filter files)
+ - named-queue names
+ - paths used by single-key lookups
+ Previously this was permitted.
+
+JH/21 Bug 2501: Fix init call in the heimdal authenticator. Previously it
+ adjusted the size of a major service buffer; this failed because the
+ buffer was in use at the time. Change to a compile-time increase in the
+ buffer size, when this authenticator is compiled into exim.
+
+JH/22 Taint-checking: move to safe-mode taint checking on all platforms. The
+ previous fast-mode was untenable in the face of glibs using mmap to
+ support larger malloc requests.
+
+PP/01 Update the openssl_options possible values through OpenSSL 1.1.1c.
+ New values supported, if defined on system where compiled:
+ allow_no_dhe_kex, cryptopro_tlsext_bug, enable_middlebox_compat,
+ no_anti_replay, no_encrypt_then_mac, prioritize_chacha, tlsext_padding
+
+JH/23 Performance improvement in the initial phase of a two-pass queue run. By
+ running a limited number of proceses in parallel, a benefit is gained. The
+ amount varies with the platform hardware and load. The use of the option
+ queue_run_in_order means we cannot do this, as ordering becomes
+ indeterminate.
+
+JH/24 Bug 2524: fix the cyrus_sasl auth driver gssapi usage. A previous fix
+ had introduced a string-copy (for ensuring NUL-termination) which was not
+ appropriate for that case, which can include embedded NUL bytes in the
+ block of data. Investigation showed the copy to actually be needless, the
+ data being length-specified.
+
+JH/25 Fix use of concurrent TLS connections under GnuTLS. When a callout was
+ done during a receiving connection, and both used TLS, global info was
+ used rather than per-connection info for tracking the state of data
+ queued for transmission. This could result in a connection hang.
+
+JH/26 Fix use of the SIZE parameter on MAIL commands, on continued connections.
+ Previously, when delivering serveral messages down a single connection
+ only the first would provide a SIZE. This was due to the size information
+ not being properly tracked.
+
+JH/27 Bug 2530: When operating in a timezone with sub-minute offset, such as
+ TAI (at 37 seconds currently), pretend to be in UTC for time-related
+ expansion and logging. Previously, spurious values such as a future
+ minute could be seen.
+
+JH/28 Bug 2533: Fix expansion of ${tr } item. When called in some situations
+ it could crash from a null-deref. This could also affect the
+ ${addresses: } operator and ${readsock } item.
+
+JH/29 Bug 2537: Fix $mime_part_count. When a single connection had a non-mime
+ message following a mime one, the variable was not reset.
+
+JH/30 When an pipelined-connect fails at the first response, assume incorrect
+ cached capability (perhaps the peer reneged?) and immediately retry in
+ non-pipelined mode.
+
+JH/31 Fix spurious detection of timeout while writing to transport filter.
+
+JH/32 Bug 2541: Fix segfault on bad cmdline -f (sender) argument. Previously
+ an attempt to copy the string was made before checking it.
+
+JH/33 Fix the dsearch lookup to return an untainted result. Previously the
+ taint of the lookup key was maintained; we now regard the presence in the
+ filesystem as sufficient validation.
+
+JH/34 Fix the readsocket expansion to not segfault when an empty "options"
+ argument is supplied.
+
+JH/35 The dsearch lookup now requires that the directory is an absolute path.
+ Previously this was not checked, and nonempty relative paths made an
+ access under Exim's current working directory.
+
+JH/36 Bug 2554: Fix msg:defer event for the hosts_max_try_hardlimit case.
+ Previously no event was raised.
+
+JH/37 Bug 2552: Fix the check on spool space during reception to use the SIZE
+ parameter supplied by the sender MAIL FROM command. Previously it was
+ ignored, and only the check_spool_space option value for the required
+ leeway checked.
+
+JH/38 Fix $dkim_key_length. This should, after a DKIM verification, present
+ the size of the signing public-key. Previously it was instead giving
+ the size of the signature hash.
+
+JH/39 DKIM verification: the RFC 8301 restriction on sizes of RSA keys is now
+ the default. See the (new) dkim_verify_min_keysizes option.
+
+JH/40 Fix a memory-handling bug: when a connection carried multiple messages
+ and an ACL use a lookup for checking either the local_part or domain,
+ stale data could be accessed. Ensure that variable references are
+ dropped between messages.
+
+JH/41 Bug 2571: Fix SPA authenticator. Running as a server, an offset supplied
+ by the client was not checked as pointing within response data before
+ being used. A malicious client could thus cause an out-of-bounds read and
+ possibly gain authentication. Fix by adding the check.
+
+JH/42 Internationalisation: change the default for downconversion in the smtp
+ transport to be "if needed". Previously it was "as previously set" for
+ the message, which usually meant "if needed" for message-submission but
+ "no" for everything else. However, MTAs have been seen using SMTPUTF8
+ even when the envelope addresses did not need it, resulting in forwarding
+ failures to non-supporting MTAs. A downconvert in such cases will be
+ a no-op on the addresses, merely dropping the use of SMTPUTF8 by the
+ transport. The change does mean that addresses needing conversion will
+ be converted when previously a delivery failure would occur.
+
+JH/43 Fix possible long line in DSN. Previously when a very long SMTP error
+ response was received it would be used unchecked in a fail-DSN, violating
+ standards on line-length limits. Truncate if needed.
+
+HS/01 Remove parameters of the link to www.open-spf.org. The linked form
+ doesn't work. (Additionally add a new main config option to configure the
+ spf_smtp_comment)
+