+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+JH/30 The (EXPERIMENTAL_DMARC) variable $dmarc_ar_header is withdrawn, being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.
+
+
+Exim version 4.90
+-----------------
+
+JH/01 Rework error string handling in TLS interface so that the caller in
+ more cases is responsible for logging. This permits library-sourced
+ string to be attached to addresses during delivery, and collapses
+ pairs of long lines into single ones.
+
+PP/01 Allow PKG_CONFIG_PATH to be set in Local/Makefile and use it correctly
+ during configuration. Wildcards are allowed and expanded.
+
+JH/02 Rework error string handling in DKIM to pass more info back to callers.
+ This permits better logging.
+
+JH/03 Rework the transport continued-connection mechanism: when TLS is active,
+ do not close it down and have the child transport start it up again on
+ the passed-on TCP connection. Instead, proxy the child (and any
+ subsequent ones) for TLS via a unix-domain socket channel. Logging is
+ affected: the continued delivery log lines do not have any DNSSEC, TLS
+ Certificate or OCSP information. TLS cipher information is still logged.
+
+JH/04 Shorten the log line for daemon startup by collapsing adjacent sets of
+ identical IP addresses on different listening ports. Will also affect
+ "exiwhat" output.
+
+PP/02 Bug 2070: uClibc defines __GLIBC__ without providing glibc headers;
+ add noisy ifdef guards to special-case this sillyness.
+ Patch from Bernd Kuhls.
+
+JH/05 Tighten up the checking in isip4 (et al): dotted-quad components larger
+ than 255 are no longer allowed.
+
+JH/06 Default openssl_options to include +no_ticket, to reduce load on peers.
+ Disable the session-cache too, which might reduce our load. Since we
+ currrectly use a new context for every connection, both as server and
+ client, there is no benefit for these.
+ GnuTLS appears to not support tickets server-side by default (we don't
+ call gnutls_session_ticket_enable_server()) but client side is enabled
+ by default on recent versions (3.1.3 +) unless the PFS priority string
+ is used (3.2.4 +).
+
+PP/03 Add $SOURCE_DATE_EPOCH support for reproducible builds, per spec at
+ <https://reproducible-builds.org/specs/source-date-epoch/>.
+
+JH/07 Fix smtp transport use of limited max_rcpt under mua_wrapper. Previously
+ the check for any unsuccessful recipients did not notice the limit, and
+ erroneously found still-pending ones.
+
+JH/08 Pipeline CHUNKING command and data together, on kernels that support
+ MSG_MORE. Only in-clear (not on TLS connections).
+
+JH/09 Avoid using a temporary file during transport using dkim. Unless a
+ transport-filter is involved we can buffer the headers in memory for
+ creating the signature, and read the spool data file once for the
+ signature and again for transmission.
+
+JH/10 Enable use of sendfile in Linux builds as default. It was disabled in
+ 4.77 as the kernel support then wasn't solid, having issues in 64bit
+ mode. Now, it's been long enough. Add support for FreeBSD also.
+
+JH/11 Bug 2104: Fix continued use of a transport connection with TLS. In the
+ case where the routing stage had gathered several addresses to send to
+ a host before calling the transport for the first, we previously failed
+ to close down TLS in the old transport process before passing the TCP
+ connection to the new process. The new one sent a STARTTLS command
+ which naturally failed, giving a failed delivery and bloating the retry
+ database. Investigation and fix prototype from Wolfgang Breyha.
+
+JH/12 Fix check on SMTP command input synchronisation. Previously there were
+ false-negatives in the check that the sender had not preempted a response
+ or prompt from Exim (running as a server), due to that code's lack of
+ awareness of the SMTP input buffering.
+
+PP/04 Add commandline_checks_require_admin option.
+ Exim drops privileges sanely, various checks such as -be aren't a
+ security problem, as long as you trust local users with access to their
+ own account. When invoked by services which pass untrusted data to
+ Exim, this might be an issue. Set this option in main configuration
+ AND make fixes to the calling application, such as using `--` to stop
+ processing options.
+
+JH/13 Do pipelining under TLS. Previously, although safe, no advantage was
+ taken. Now take care to pack both (client) MAIL,RCPT,DATA, and (server)
+ responses to those, into a single TLS record each way (this usually means
+ a single packet). As a side issue, smtp_enforce_sync now works on TLS
+ connections.
+
+PP/05 OpenSSL/1.1: use DH_bits() for more accurate DH param sizes. This
+ affects you only if you're dancing at the edge of the param size limits.
+ If you are, and this message makes sense to you, then: raise the
+ configured limit or use OpenSSL 1.1. Nothing we can do for older
+ versions.
+
+JH/14 For the "sock" variant of the malware scanner interface, accept an empty
+ cmdline element to get the documented default one. Previously it was
+ inaccessible.
+
+JH/15 Fix a crash in the smtp transport caused when two hosts in succession
+ are unsuable for non-message-specific reasons - eg. connection timeout,
+ banner-time rejection.
+
+JH/16 Fix logging of delivery remote port, when specified by router, under
+ callout/hold.
+
+PP/06 Repair manualroute's ability to take options in any order, even if one
+ is the name of a transport.
+ Fixes bug 2140.
+
+HS/01 Cleanup, prevent repeated use of -p/-oMr (CVE-2017-1000369)
+
+JH/17 Change the list-building routines interface to use the expanding-string
+ triplet model, for better allocation and copying behaviour.
+
+JH/18 Prebuild the data-structure for "builtin" macros, for faster startup.
+ Previously it was constructed the first time a possibly-matching string
+ was met in the configuration file input during startup; now it is done
+ during compilation.
+
+JH/19 Bug 2141: Use the full-complex API for Berkeley DB rather than the legacy-
+ compatible one, to avoid the (poorly documented) possibility of a config
+ file in the working directory redirecting the DB files, possibly correpting
+ some existing file. CVE-2017-10140 assigned for BDB.
+
+JH/20 Bug 2147: Do not defer for a verify-with-callout-and-random which is not
+ cache-hot. Previously, although the result was properly cached, the
+ initial verify call returned a defer.
+
+JH/21 Bug 2151: Avoid using SIZE on the MAIL for a callout verify, on any but
+ the main verify for receipient in uncached-mode.
+
+JH/22 Retire historical build files to an "unsupported" subdir. These are
+ defined as "ones for which we have no current evidence of testing".
+
+JH/23 DKIM: enforce the DNS pubkey record "h" permitted-hashes optional field,
+ if present. Previously it was ignored.
+
+JH/24 Start using specified-initialisers in C structure init coding. This is
+ a C99 feature (it's 2017, so now considered safe).
+
+JH/25 Use one-bit bitfields for flags in the "addr" data structure. Previously
+ if was a fixed-sized field and bitmask ops via macros; it is now more
+ extensible.
+
+PP/07 GitHub PR 56: Apply MariaDB build fix.
+ Patch provided by Jaroslav Škarvada.
+
+PP/08 Bug 2161: Fix regression in sieve quoted-printable handling introduced
+ during Coverity cleanups [4.87 JH/47]
+ Diagnosis and fix provided by Michael Fischer v. Mollard.
+
+JH/26 Fix DKIM bug: when the pseudoheader generated for signing was exactly
+ the right size to place the terminating semicolon on its own folded
+ 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
+ and confused the parent.
+
+JH/27 Fix SOCKS bug: an unitialized pointer was deref'd by the transport process
+ which could crash as a result. This could lead to undeliverable messages.
+
+JH/28 Logging: "next input sent too soon" now shows where input was truncated
+ for log purposes.
+
+JH/29 Fix queue_run_in_order to ignore the PID portion of the message ID. This
+ matters on fast-turnover and PID-randomising systems, which were getting
+ out-of-order delivery.
+
+JH/30 Fix a logging bug on aarch64: an unsafe routine was previously used for
+ a possibly-overlapping copy. The symptom was that "Remote host closed
+ connection in response to HELO" was logged instead of the actual 4xx
+ error for the HELO.
+
+JH/31 Fix CHUNKING code to properly flush the unwanted chunk after an error.
+ Previously only that bufferd was discarded, resulting in SYMTP command
+ desynchronisation.
+
+JH/32 DKIM: when a message has multiple signatures matching an identity given
+ in dkim_verify_signers, run the dkim acl once for each. Previously only
+ one run was done. Bug 2189.
+
+JH/33 Downgrade an unfound-list name (usually a typo in the config file) from
+ "panic the current process" to "deliberately defer". The panic log is
+ still written with the problem list name; the mail and reject logs now
+ get a temp-reject line for the message that was being handled, saying
+ something like "domains check lookup or other defer". The SMTP 451
+ message is still "Temporary local problem".
+
+JH/34 Bug 2199: Fix a use-after-free while reading smtp input for header lines.
+ A crafted sequence of BDAT commands could result in in-use memory beeing
+ freed. CVE-2017-16943.
+
+HS/03 Bug 2201: Fix checking for leading-dot on a line during headers reading
+ from SMTP input. Previously it was always done; now only done for DATA
+ and not BDAT commands. CVE-2017-16944.
+
+JH/35 Bug 2201: Flush received data in BDAT mode after detecting an error fatal
+ to the message (such as an overlong header line). Previously this was
+ not done and we did not exit BDAT mode. Followon from the previous item
+ though a different problem.
+
+
+Exim version 4.89
+-----------------
+
+JH/01 Bug 1922: Support IDNA2008. This has slightly different conversion rules
+ than -2003 did; needs libidn2 in addition to libidn.
+
+JH/02 The path option on a pipe transport is now expanded before use.
+
+PP/01 GitHub PR 50: Do not call ldap_start_tls_s on ldapi:// connections.
+ Patch provided by "Björn", documentation fix added too.
+
+JH/03 Bug 2003: fix Proxy Protocol v2 handling: the address size field was
+ missing a wire-to-host endian conversion.
+
+JH/04 Bug 2004: fix CHUNKING in non-PIPELINEING mode. Chunk data following
+ close after a BDAT command line could be taken as a following command,
+ giving a synch failure. Fix by only checking for synch immediately
+ before acknowledging the chunk.
+
+PP/02 GitHub PR 52: many spelling fixes, which include fixing parsing of
+ no_require_dnssec option and creation of _HAVE_TRANSPORT_APPEND_MAILDIR
+ macro. Patches provided by Josh Soref.
+
+JH/05 Have the EHLO response advertise VRFY, if there is a vrfy ACL defined.
+ Previously we did not; the RFC seems ambiguous and VRFY is not listed
+ by IANA as a service extension. However, John Klensin suggests that we
+ should.
+
+JH/06 Bug 2017: Fix DKIM verification in -bh test mode. The data feed into
+ the dkim code may be unix-mode line endings rather than smtp wire-format
+ CRLF, so prepend a CR to any bare LF.
+
+JH/07 Rationalise the coding for callout smtp conversations and transport ones.
+ As a side-benfit, callouts can now use PIPELINING hence fewer round-trips.
+
+JH/08 Bug 2016: Fix DKIM verification vs. CHUNKING. Any BDAT commands after
+ the first were themselves being wrongly included in the feed into dkim
+ processing; with most chunk sizes in use this resulted in an incorrect
+ body hash calculated value.
+
+JH/09 Bug 2014: permit inclusion of a DKIM-Signature header in a received
+ DKIM signature block, for verification. Although advised against by
+ standards it is specifically not ruled illegal.
+
+JH/10 Bug 2025: Fix reception of (quoted) local-parts with embedded spaces.
+
+JH/11 Bug 2029: Fix crash in DKIM verification when a message signature block is
+ missing a body hash (the bh= tag).
+
+JH/12 Bug 2018: Re-order Proxy Protocol startup versus TLS-on-connect startup.
+ It seems that HAProxy sends the Proxy Protocol information in clear and
+ only then does a TLS startup, so do the same.
+
+JH/13 Bug 2027: Avoid attempting to use TCP Fast Open for non-transport client
+ TCP connections (such as for Spamd) unless the daemon successfully set
+ Fast Open mode on its listening sockets. This fixes breakage seen on
+ too-old kernels or those not configured for Fast Open, at the cost of
+ requiring both directions being enabled for TFO, and TFO never being used
+ by non-daemon-related Exim processes.
+
+JH/14 Bug 2000: Reject messages recieved with CHUNKING but with malformed line
+ endings, at least on the first header line. Try to canonify any that get
+ past that check, despite the cost.
+
+JH/15 Angle-bracket nesting (an error inserted by broken sendmails) levels are
+ now limited to an arbitrary five deep, while parsing addresses with the
+ strip_excess_angle_brackets option enabled.
+
+PP/03 Bug 2018: For Proxy Protocol and TLS-on-connect, do not over-read and
+ instead leave the unprompted TLS handshake in socket buffer for the
+ TLS library to consume.
+
+PP/04 Bug 2018: Also handle Proxy Protocol v2 safely.
+
+PP/05 FreeBSD compat: handle that Ports no longer create /usr/bin/perl
+
+JH/16 Drop variables when they go out of scope. Memory management drops a whole
+ region in one operation, for speed, and this leaves assigned pointers
+ dangling. Add checks run only under the testsuite which checks all
+ variables at a store-reset and panics on a dangling pointer; add code
+ explicitly nulling out all the variables discovered. Fixes one known
+ bug: a transport crash, where a dangling pointer for $sending_ip_address
+ originally assigned in a verify callout, is re-used.
+
+PP/06 Drop '.' from @INC in various Perl scripts.
+
+PP/07 Switch FreeBSD iconv to always use the base-system libc functions.
+
+PP/08 Reduce a number of compilation warnings under clang; building with
+ CC=clang CFLAGS+=-Wno-dangling-else -Wno-logical-op-parentheses
+ should be warning-free.
+
+JH/17 Fix inbound CHUNKING when DKIM disabled at runtime.
+
+HS/01 Fix portability problems introduced by PP/08 for platforms where
+ realloc(NULL) is not equivalent to malloc() [SunOS et al].
+
+HS/02 Bug 1974: Fix missing line terminator on the last received BDAT
+ chunk. This allows us to accept broken chunked messages. We need a more
+ general solution here.
+
+PP/09 Wrote util/chunking_fixqueue_finalnewlines.pl to help recover
+ already-broken messages in the queue.
+
+JH/18 Bug 2061: Fix ${extract } corrupting an enclosing ${reduce } $value.
+
+JH/19 Fix reference counting bug in routing-generated-address tracking.
+
+
+Exim version 4.88