Fix spool space check to account for SIZE. Bug 2552

[exim.git] / doc / doc-txt / ChangeLog

This document describes *changes* to previous versions, that might
affect Exim's operation, with an unchanged configuration file.  For new
options, and new features, see the NewStuff file next to this ChangeLog.


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 receipients as tainted.

JH/06 Bug 340: Remove the daemon pid file on exit, whe 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.


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.

JH/06 Fix buggy handling of autoreply bounce_return_size_limit, and a possible
      buffer overrun for (non-chunking) other transports.

JH/07 GnuTLS: Our use of late (post-handshake) certificate verification, under
      TLS1.3, means that a server rejecting a client certificate is not visible
      to the client until the first read of encrypted data (typically the
      response to EHLO).  Add detection for that case and treat it as a failed
      TLS connection attempt, so that the normal retry-in-clear can work (if
      suitably configured).

JB/01 Bug 2375: fix expansions of 822 addresses having comments in local-part
      and/or domain.  Found and fixed by Jason Betts.

JH/08 Add hardening against SRV & TLSA lookups the hit CNAMEs (a nonvalid
      configuration).  If a CNAME target was not a wellformed name pattern, a
      crash could result.

JH/09 Logging: Fix initial listening-on line for multiple ports for an IP when
      the OS reports them interleaved with other addresses.

JH/10 OpenSSL: Fix aggregation of messages.  Previously, when PIPELINING was
      used both for input and for a verify callout, both encrypted, SMTP
      responses being sent by the server could be lost.  This resulted in
      dropped connections and sometimes bounces generated by a peer sending
      to this system.

JH/11 Harden plaintext authenticator against a badly misconfigured client-send
      string.  Previously it was possible to cause undefined behaviour in a
      library routine (usually a crash).  Found by "zerons".

JH/12 Bug 2384: fix "-bP smtp_receive_timeout".  Previously it returned no
      output.

JH/13 Bug 2386: Fix builds with Dane under LibreSSL 2.9.0 onward.  Some old
      API was removed, so update to use the newer ones.

JH/14 Bug 1891: Close the log file if receiving a non-smtp message, without
      any timeout set, is taking a long time.  Previously we would hang on to a
      rotated logfile "forever" if the input was arriving with long gaps
      (a previous attempt to fix addressed lack, for a long time, of initial
      input).

HS/01 Bug 2390: Use message_id for tempfile creation to avoid races in a
      shared (NFS) environment. The length of the tempfile name is now
      4 + 16 ("hdr.$message_exim_id") which might break on file
      systems which restrict the file name length to lower values.
      (It was "hdr.$pid".)

HS/02 Bug 2390: Use message_id for tempfile creation to avoid races in a
      shared (NFS) environment.

HS/03 Bug 2392: exigrep does case sensitive *option* processing (as it
      did for all versions <4.90). Notably -M, -m, --invert, -I may be
      affected.

JH/15 Use unsigned when creating bitmasks in macros, to avoid build errors
      on some platforms for bit 31.

JH/16 GnuTLS: rework ciphersuite strings under recent library versions.  Thanks
      to changes apparently associated with TLS1.3 handling some of the APIs
      previously used were either nonfunctional or inappropriate.  Strings
      like TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM__AEAD:256
      and TLS1.2:ECDHE_SECP256R1__RSA_SHA256__AES_128_CBC__SHA256:128 replace
      the previous TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256 .
      This affects log line X= elements, the $tls_{in,out}_cipher variables,
      and the use of specific cipher names in the encrypted= ACL condition.

JH/17 OpenSSL: the default openssl_options now disables ssl_v3.

JH/18 GnuTLS: fix $tls_out_ocsp under hosts_request_ocsp. Previously the
      verification result was not updated unless hosts_require_ocsp applied.

JH/19 Bug 2398: fix listing of a named-queue.  Previously, even with the option
      queue_list_requires_admin set to false, non-admin users were denied the
      facility.

JH/20 Bug 2389: fix server advertising of usable certificates, under GnuTLS in
      directory-of-certs mode.  Previously they were advertised despite the
      documentation.

JH/21 The smtp transport option "hosts_noproxy_tls" is now unset by default.
      A single TCP connection by a client will now hold a TLS connection open
      for multiple message deliveries, by default.  Previoud the default was to
      not do so.

JH/22 The smtp transport option "hosts_try_dane" now enables all hosts by
      default.  If built with the facility, DANE will be used.  The facility
      SUPPORT_DANE is now enabled in the prototype build Makefile "EDITME".

JH/23 The build default is now for TLS to be included; the SUPPORT_TLS define
      is replaced with DISABLE_TLS.  Either USE_GNUTLS or (the new) USE_OPENSSL
      must be defined and you must still, unless you define DISABLE_TLS, manage
      the the include-dir and library-file requirements that go with that
      choice.  Non-TLS builds are still supported.

JH/24 Fix duplicated logging of peer name/address, on a transport connection-
      reject under TFO.

JH/25 The smtp transport option "hosts_try_fastopen" now enables all hosts by
      default.  If the platform supports and has the facility enabled, it will
      be requested on all coneections.

JH/26 The PIPE_CONNECT facility is promoted from experimental status and is now
      controlled by the build-time option SUPPORT_PIPE_CONNECT.

PP/01 Unbreak heimdal_gssapi, broken in 4.92.

JH/27 Bug 2404: Use the main-section configuration option "dsn_from" for
      success-DSN messages.  Previously the From: header was always the default
      one for these; the option was ignored.

JH/28 Fix the timeout on smtp response to apply to the whole response.
      Previously it was reset for every read, so a teergrubing peer sending
      single bytes within the time limit could extend the connection for a
      long time.  Credit to Qualsys Security Advisory Team for the discovery.

JH/29 Fix DSN Final-Recipient: field.  Previously it was the post-routing
      delivery address, which leaked information of the results of local
      forwarding.  Change to the original envelope recipient address, per
      standards.

JH/30 Bug 2411: Fix DSN generation when RFC 3461 failure notification is
      requested.  Previously not bounce was generated and a log entry of
      error ignored was made.

JH/31 Avoid re-expansion in ${sort } expansion. (CVE-2019-13917)

JH/32 Introduce a general tainting mechanism for values read from the input
      channel, and values derived from them.  Refuse to expand any tainted
      values, to catch one form of exploit.

JH/33 Bug 2413: Fix dkim_strict option.  Previously the expansion result
      was unused and the unexpanded text used for the test.  Found and
      fixed by Ruben Jenster.

JH/34 Fix crash after TLS shutdown.  When the TCP/SMTP channel was left open,
      an attempt to use a TLS library read routine dereffed a nul pointer,
      causing a segfault.

JH/35 Bug 2409: filter out-of-spec chars from callout response before using
      them in our smtp response.

JH/36 Have the general router option retry_use_local_part default to true when
      any of the restrictive preconditions are set (to anything).  Previously it
      was only for check_local user.  The change removes one item of manual
      configuration which is required for proper retries when a remote router
      handles a subset of addresses for a domain.

JH/37 Appendfile: when evaluating quota use (non-quota_size_regex) take the file
      link count into consideration.

HS/04 Fix handling of very log lines in -H files. If a -<key> <value> line
      caused the extension of big_buffer, the following lines were ignored.

JH/38 Bug 1395: Teach the DNS negative-cache about TTL value from the SOA in
      accordance with RFC 2308.  Previously there was no expiry, so a longlived
      receive process (eg. due to ACL delays) versus a short SOA value could
      surprise.

HS/05 Handle trailing backslash gracefully. (CVE-2019-15846)

JH/39 Promote DMARC support to mainline.

JH/40 Bug 2452: Add a References: header to DSNs.

JH/41 With GnuTLS 3.6.0 (and later) do not attempt to manage Diffie-Hellman
      parameters.  The relevant library call is documented as "Deprecated: This
      function is unnecessary and discouraged on GnuTLS 3.6.0 or later. Since
      3.6.0, DH parameters are negotiated following RFC7919."

HS/06 Change the default of dnssec_request_domains to "*"

JH/42 Bug 2545: Fix CHUNKING for all RCPT commands rejected.  Previously we
      carried on and emitted a BDAT command, even when PIPELINING was not
      active.

JH/43 Bug 2465: Fix taint-handling in dsearch lookup.  Previously a nontainted
      buffer was used for the filename, resulting in a trap when tainted
      arguments (eg. $domain) were used.

JH/44 With OpenSSL 1.1.1 (onwards) disable renegotiation for TLS1.2 and below;
      recommended to avoid a possible server-load attack.  The feature can be
      re-enabled via the openssl_options main cofiguration option.

JH/45 local_scan API: documented the current smtp_printf() call. This changed
      for version 4.90 - adding a "more data" boolean to the arguments.
      Bumped the ABI version number also, this having been missed previously;
      release versions 4.90 to 4.92.3 inclusive were effectively broken in
      respect of usage of smtp_printf() by either local_scan code or libraries
      accessed via the ${dlfunc } expansion item.  Both will need coding
      adjustment for any calls to smtp_printf() to match the new function
      signature; a FALSE value for the new argument is always safe.

JH/46 FreeBSD: fix use of the sendfile() syscall.  The shim was not updating
      the file-offset (which the Linux syscall does, and exim expects); this
      resulted in an indefinite loop.

JH/47 ARC: fix crash in signing, triggered when a configuration error failed
      to do ARC verification.  The Authentication-Results: header line added
      by the configuration then had no ARC item.


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
      the allocate and data copy operations duplicated in both (!) of the
      extant use locations.

JH/02 Disallow '/' characters in queue names specified for the "queue=" ACL
      modifier.  This matches the restriction on the commandline.

JH/03 Fix pgsql lookup for multiple result-tuples with a single column.
      Previously only the last row was returned.

JH/04 Bug 2217: Tighten up the parsing of DKIM signature headers. Previously
      we assumed that tags in the header were well-formed, and parsed the
      element content after inspecting only the first char of the tag.
      Assumptions at that stage could crash the receive process on malformed
      input.

JH/05 Bug 2215: Fix crash associated with dnsdb lookup done from DKIM ACL.
      While running the DKIM ACL we operate on the Permanent memory pool so that
      variables created with "set" persist to the DATA ACL.  Also (at any time)
      DNS lookups that fail create cache records using the Permanent pool.  But
      expansions release any allocations made on the current pool - so a dnsdb
      lookup expansion done in the DKIM ACL releases the memory used for the
      DNS negative-cache, and bad things result.  Solution is to switch to the
      Main pool for expansions.
      While we're in that code, add checks on the DNS cache during store_reset,
      active in the testsuite.
      Problem spotted, and debugging aided, by Wolfgang Breyha.

JH/06 Fix issue with continued-connections when the DNS shifts unreliably.
      When none of the hosts presented to a transport match an already-open
      connection, close it and proceed with the list.  Previously we would
      queue the message.  Spotted by Lena with Yahoo, probably involving
      round-robin DNS.

JH/07 Bug 2214: Fix SMTP responses resulting from non-accept result of MIME ACL.
      Previously a spurious "250 OK id=" response was appended to the proper
      failure response.

JH/08 The "support for" informational output now, which built with Content
      Scanning support, has a line for the malware scanner interfaces compiled
      in.  Interface can be individually included or not at build time.

JH/09 The "aveserver", "kavdaemon" and "mksd" interfaces are now not included
      by the template makefile "src/EDITME".  The "STREAM" support for an older
      ClamAV interface method is removed.

JH/10 Bug 2223: Fix mysql lookup returns for the no-data case (when the number of
      rows affected is given instead).

JH/11 The runtime Berkeley DB library version is now additionally output by
      "exim -d -bV".  Previously only the compile-time version was shown.

JH/12 Bug 2230: Fix cutthrough routing for nonfirst messages in an initiating
      SMTP connection.  Previously, when one had more receipients than the
      first, an abortive onward connection was made.  Move to full support for
      multiple onward connections in sequence, handling cutthrough connection
      for all multi-message initiating connections.

JH/13 Bug 2229: Fix cutthrough routing for nonstandard port numbers defined by
      routers.  Previously, a multi-recipient message would fail to match the
      onward-connection opened for the first recipient, and cause its closure.

JH/14 Bug 2174: A timeout on connect for a callout was also erroneously seen as
      a timeout on read on a GnuTLS initiating connection, resulting in the
      initiating connection being dropped.  This mattered most when the callout
      was marked defer_ok.  Fix to keep the two timeout-detection methods
      separate.

JH/15 Relax results from ACL control request to enable cutthrough, in
      unsupported situations, from error to silently (except under debug)
      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
-----------------

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 were 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
-----------------

JH/01 Use SIZE on MAIL FROM in a cutthrough connection, if the destination
      supports it and a size is available (ie. the sending peer gave us one).

JH/02 The obsolete acl condition "demime" is removed (finally, after ten
      years of being deprecated). The replacements are the ACLs
      acl_smtp_mime and acl_not_smtp_mime.

JH/03 Upgrade security requirements imposed for hosts_try_dane: previously
      a downgraded non-dane trust-anchor for the TLS connection (CA-style)
      or even an in-clear connection were permitted.  Now, if the host lookup
      was dnssec and dane was requested then the host is only used if the
      TLSA lookup succeeds and is dnssec.  Further hosts (eg. lower priority
      MXs) will be tried (for hosts_try_dane though not for hosts_require_dane)
      if one fails this test.
      This means that a poorly-configured remote DNS will make it incommunicado;
      but it protects against a DNS-interception attack on it.

JH/04 Bug 1810: make continued-use of an open smtp transport connection
      non-noisy when a race steals the message being considered.

JH/05 If main configuration option tls_certificate is unset, generate a
      self-signed certificate for inbound TLS connections.

JH/06 Bug 165: hide more cases of password exposure - this time in expansions
      in rewrites and routers.

JH/07 Retire gnutls_require_mac et.al.  These were nonfunctional since 4.80
      and logged a warning sing 4.83; now they are a configuration file error.

JH/08 Bug 1836: Fix crash in VRFY handling when handed an unqualified name
      (lacking @domain).  Apply the same qualification processing as RCPT.

JH/09 Bug 1804: Avoid writing msglog files when in -bh or -bhc mode.

JH/10 Support ${sha256:} applied to a string (as well as the previous
      certificate).

JH/11 Cutthrough: avoid using the callout hints db on a verify callout when
      a cutthrough deliver is pending, as we always want to make a connection.
      This also avoids re-routing the message when later placing the cutthrough
      connection after a verify cache hit.
      Do not update it with the verify result either.

JH/12 Cutthrough: disable when verify option success_on_redirect is used, and
      when routing results in more than one destination address.

JH/13 Cutthrough: expand transport dkim_domain option when testing for dkim
      signing (which inhibits the cutthrough capability).  Previously only
      the presence of an option was tested; now an expansion evaluating as
      empty is permissible (obviously it should depend only on data available
      when the cutthrough connection is made).

JH/14 Fix logging of errors under PIPELINING.  Previously the log line giving
      the relevant preceding SMTP command did not note the pipelining mode.

JH/15 Fix counting of empty lines in $body_linecount and $message_linecount.
      Previously they were not counted.

JH/16 DANE: treat a TLSA lookup response having all non-TLSA RRs, the same
      as one having no matching records.  Previously we deferred the message
      that needed the lookup.

JH/17 Fakereject: previously logged as a normal message arrival "<="; now
      distinguished as "(=".

JH/18 Bug 1867: make the fail_defer_domains option on a dnslookup router work
      for missing MX records.  Previously it only worked for missing A records.

JH/19 Bug 1850: support Radius libraries that return REJECT_RC.

JH/20 Bug 1872: Ensure that acl_smtp_notquit is run when the connection drops
      after the data-go-ahead and data-ack.  Patch from Jason Betts.

JH/21 Bug 1846: Send DMARC forensic reports for reject and quarantine results,
      even for a "none" policy.  Patch from Tony Meyer.

JH/22 Fix continued use of a connection for further deliveries. If a port was
      specified by a router, it must also match for the delivery to be
      compatible.

JH/23 Bug 1874: fix continued use of a connection for further deliveries.
      When one of the recipients of a message was unsuitable for the connection
      (has no matching addresses), we lost track of needing to mark it
      deferred.  As a result mail would be lost.

JH/24 Bug 1832: Log EHLO response on getting conn-close response for HELO.

JH/25 Decoding ACL controls is now done using a binary search; the source code
      takes up less space and should be simpler to maintain.  Merge the ACL
      condition decode tables also, with similar effect.

JH/26 Fix problem with one_time used on a redirect router which returned the
      parent address unchanged.  A retry would see the parent address marked as
      delivered, so not attempt the (identical) child.  As a result mail would
      be lost.

JH/27 Fix a possible security hole, wherein a process operating with the Exim
      UID can gain a root shell.  Credit to http://www.halfdog.net/ for
      discovery and writeup.  Ubuntu bug 1580454; no bug raised against Exim
      itself :(

JH/28 Enable {spool,log} filesystem space and inode checks as default.
      Main config options check_{log,spool}_{inodes,space} are now
      100 inodes, 10MB unless set otherwise in the configuration.

JH/29 Fix the connection_reject log selector to apply to the connect ACL.
      Previously it only applied to the main-section connection policy
      options.

JH/30 Bug 1897: fix callouts connection fallback from TLS to cleartext.

PP/01 Changed default Diffie-Hellman parameters to be Exim-specific, created
      by me.  Added RFC7919 DH primes as an alternative.

PP/02 Unbreak build via pkg-config with new hash support when crypto headers
      are not in the system include path.

JH/31 Fix longstanding bug with aborted TLS server connection handling.  Under
      GnuTLS, when a session startup failed (eg because the client disconnected)
      Exim did stdio operations after fclose.  This was exposed by a recent
      change which nulled out the file handle after the fclose.

JH/32 Bug 1909: Fix OCSP proof verification for cases where the proof is
      signed directly by the cert-signing cert, rather than an intermediate
      OCSP-signing cert.  This is the model used by LetsEncrypt.

JH/33 Bug 1914: Ensure socket is nonblocking before draining after SMTP QUIT.

HS/01 Fix leak in verify callout under GnuTLS, about 3MB per recipient on
      an incoming connection.

HS/02 Bug 1802: Do not half-close the connection after sending a request
      to rspamd.

HS/03 Use "auto" as the default EC curve parameter. For OpenSSL < 1.0.2
      fallback to "prime256v1".

JH/34 SECURITY: Use proper copy of DATA command in error message.
      Could leak key material.  Remotely exploitable.  CVE-2016-9963.


Exim version 4.87
-----------------

JH/01 Bug 1664: Disable OCSP for GnuTLS library versions at/before 3.3.16
      and 3.4.4 - once the server is enabled to respond to an OCSP request
      it does even when not requested, resulting in a stapling non-aware
      client dropping the TLS connection.

TF/01 Code cleanup: Overhaul the debug_selector and log_selector machinery to
      support variable-length bit vectors. No functional change.

TF/02 Improve the consistency of logging incoming and outgoing interfaces.
      The I= interface field on outgoing lines is now after the H= remote
      host field, same as incoming lines. There is a separate
      outgoing_interface log selector which allows you to disable the
      outgoing I= field.

JH/02 Bug 728: Close logfiles after a daemon-process "exceptional" log write.
      If not running log_selector +smtp_connection the mainlog would be held
      open indefinitely after a "too many connections" event, including to a
      deleted file after a log rotate. Leave the per net connection logging
      leaving it open for efficiency as that will be quickly detected by the
      check on the next write.

HS/01 Bug 1671: Fix post transport crash.
      Processing the wait-<transport> messages could crash the delivery
      process if the message IDs didn't exist for some reason. When
      using 'split_spool_directory=yes' the construction of the spool
      file name failed already, exposing the same netto behaviour.

JH/03 Bug 425: Capture substrings in $regex1, $regex2 etc from regex &
      mime_regex ACL conditions.

JH/04 Bug 1686: When compiled with EXPERIMENTAL_DSN_INFO: Add extra information
      to DSN fail messages (bounces): remote IP, remote greeting, remote response
      to HELO, local diagnostic string.

JH/05 Downgrade message for a TLS-certificate-based authentication fail from
      log line to debug.  Even when configured with a tls authenticator many
      client connections are expected to not authenticate in this way, so
      an authenticate fail is not an error.

HS/02 Add the Exim version string to the process info.  This way exiwhat
      gives some more detail about the running daemon.

JH/06 Bug 1395: time-limit caching of DNS lookups, to the TTL value.  This may
      matter for fast-change records such as DNSBLs.

JH/07 Bug 1678: Always record an interface option value, if set,  as part of a
      retry record, even if constant.  There may be multiple transports with
      different interface settings and the retry behaviour needs to be kept
      distinct.

JH/08 Bug 1586: exiqgrep now refuses to run if there are unexpected arguments.

JH/09 Bug 1700: ignore space & tab embedded in base64 during decode.

JH/10 Bug 840: fix log_defer_output option of pipe transport

JH/11 Bug 830: use same host for all RCPTS of a message, even under
      hosts_randomize.  This matters a lot when combined with mua_wrapper.

JH/12 Bug 1706: percent and underbar characters are no longer escaped by the
      ${quote_pgsql:<string>} operator.

JH/13 Bug 1708: avoid misaligned access in cached lookup.

JH/14 Change header file name for freeradius-client.  Relevant if compiling
      with Radius support; from the Gentoo tree and checked under Fedora.

JH/15 Bug 1712: Introduce $prdr_requested flag variable

JH/16 Bug 1714: Permit an empty string as expansion result for transport
      option transport_filter, meaning no filtering.

JH/17 Bug 1713: Fix non-PDKIM_DEBUG build.  Patch from Jasen Betts.

JH/18 Bug 1709: When built with TLS support, the tls_advertise_hosts option now
      defaults to "*" (all hosts).  The variable is now available when not built
      with TLS, default unset, mainly to enable keeping the testsuite sane.
      If a server certificate is not supplied (via tls_certificate) an error is
      logged, and clients will find TLS connections fail on startup.  Presumably
      they will retry in-clear.
      Packagers of Exim are strongly encouraged to create a server certificate
      at installation time.

HS/03 Add -bP config_file as a synonym for -bP configure_file, for consistency
      with the $config_file variable.

JH/19 Two additional event types: msg:rcpt:defer and msg:rcpt:host:defer. Both
      in transport context, after the attempt, and per-recipient. The latter type
      is per host attempted.  The event data is the error message, and the errno
      information encodes the lookup type (A vs. MX) used for the (first) host,
      and the trailing two digits of the smtp 4xx response.

GF/01 Bug 1715: Fix for race condition in exicyclog, where exim could attempt
      to write to mainlog (or rejectlog, paniclog) in the window between file
      creation and permissions/ownership being changed. Particularly affects
      installations where exicyclog is run as root, rather than exim user;
      result is that the running daemon panics and dies.

JH/20 Bug 1701: For MySQL lookups, support MySQL config file option group names.

JH/21 Bug 1720: Add support for priority groups and weighted-random proxy
      selection for the EXPERIMENTAL_SOCKS feature, via new per-proxy options
      "pri" and "weight".  Note that the previous implicit priority given by the
      list order is no longer honoured.

JH/22 Bugs 963, 1721: Fix some corner cases in message body canonicalization
      for DKIM processing.

JH/23 Move SOCKS5 support from Experimental to mainline, enabled for a build
      by defining SUPPORT_SOCKS.

JH/26 Move PROXY support from Experimental to mainline, enabled for a build
      by defining SUPPORT_PROXY.  Note that the proxy_required_hosts option
      is renamed to hosts_proxy, and the proxy_{host,target}_{address,port}.
      variables are renamed to proxy_{local,external}_{address,port}.

JH/27 Move Internationalisation support from Experimental to mainline, enabled
      for a build by defining SUPPORT_I18N

JH/28 Bug 1745: Fix redis lookups to handle (quoted) spaces embedded in parts
      of the query string, and make ${quote_redis:} do that quoting.

JH/29 Move Events support from Experimental to mainline, enabled by default
      and removable for a build by defining DISABLE_EVENT.

JH/30 Updated DANE implementation code to current from Viktor Dukhovni.

JH/31 Fix bug with hosts_connection_nolog and named-lists which were wrongly
      cached by the daemon.

JH/32 Move Redis support from Experimental to mainline, enabled for a build
      by defining LOOKUP_REDIS. The libhiredis library is required.

JH/33 Bug 1748: Permit ACL dnslists= condition in non-smtp ACLs if explicit
      keys are given for lookup.

JH/34 Bug 1192: replace the embedded copy of PolarSSL RSA routines in the DKIM
      support, by using OpenSSL or GnuTLS library ones.  This means DKIM is
      only supported when built with TLS support.  The PolarSSL SHA routines
      are still used when the TLS library is too old for convenient support.

JH/35 Require SINGLE_DH_USE by default in OpenSSL (main config option
      openssl_options), for security.  OpenSSL forces this from version 1.1.0
      server-side so match that on older versions.

JH/36 Bug 1778: longstanding bug in memory use by the ${run } expansion: A fresh
      allocation for $value could be released as the expansion processing
      concluded, but leaving the global pointer active for it.

JH/37 Bug 1769: Permit a VRFY ACL to override the default 252 response,
      and to use the domains and local_parts ACL conditions.

JH/38 Fix cutthrough bug with body lines having a single dot. The dot was
      incorrectly not doubled on cutthrough transmission, hence seen as a
      body-termination at the receiving system - resulting in truncated mails.
      Commonly the sender saw a TCP-level error, and retransmitted the message
      via the normal store-and-forward channel. This could result in duplicates
      received - but deduplicating mailstores were liable to retain only the
      initial truncated version.

JH/39 Bug 1781: Fix use of DKIM private-keys having trailing '=' in the base-64.

JH/40 Fix crash in queryprogram router when compiled with EXPERIMENTAL_SRS.

JH/41 Bug 1792: Fix selection of headers to sign for DKIM: bottom-up.  While
      we're in there, support oversigning also; bug 1309.

JH/42 Bug 1796: Fix error logged on a malware scanner connection failure.

HS/04 Add support for keep_environment and add_environment options.

JH/43 Tidy coding issues detected by gcc --fsanitize=undefined.  Some remain;
      either intentional arithmetic overflow during PRNG, or testing config-
      induced overflows.

JH/44 Bug 1800: The combination of a -bhc commandline option and cutthrough
      delivery resulted in actual delivery.  Cancel cutthrough before DATA
      stage.

JH/45 Fix cutthrough, when connection not opened by verify and target hard-
      rejects a recipient: pass the reject to the originator.

JH/46 Multiple issues raised by Coverity. Some were obvious or plausible bugs.
      Many were false-positives and ignorable, but it's worth fixing the
      former class.

JH/47 Fix build on HP-UX and older Solaris, which need (un)setenv now also
      for the new environment-manipulation done at startup.  Move the routines
      from being local to tls.c to being global via the os.c file.

JH/48 Bug 1807: Fix ${extract } for the numeric/3-string case. While preparsing
      an extract embedded as result-arg for a map, the first arg for extract
      is unavailable so we cannot tell if this is a numbered or keyed
      extraction.  Accept either.


Exim version 4.86
-----------------

JH/01 Bug 1545: The smtp transport option "retry_include_ip_address" is now
      expanded.

JH/02 The smtp transport option "multi_domain" is now expanded.

JH/03 The smtp transport now requests PRDR by default, if the server offers
      it.

JH/04 Certificate name checking on server certificates, when exim is a client,
      is now done by default.  The transport option tls_verify_cert_hostnames
      can be used to disable this per-host.  The build option
      EXPERIMENTAL_CERTNAMES is withdrawn.

JH/05 The value of the tls_verify_certificates smtp transport and main options
      default to the word "system" to access the system default CA bundle.
      For GnuTLS, only version 3.0.20 or later.

JH/06 Verification of the server certificate for a TLS connection is now tried
      (but not required) by default.  The verification status is now logged by
      default, for both outbound TLS and client-certificate supplying inbound
      TLS connections

JH/07 Changed the default rfc1413 lookup settings to disable calls.  Few
      sites use this now.

JH/08 The EXPERIMENTAL_DSN compile option is no longer needed; all Delivery
      Status Notification (bounce) messages are now MIME format per RFC 3464.
      Support for RFC 3461 DSN options NOTIFY,ENVID,RET,ORCPT can be advertised
      under the control of the dsn_advertise_hosts option, and routers may
      have a dsn_lasthop option.

JH/09 A timeout of 2 minutes is now applied to all malware scanner types by
      default, modifiable by a malware= option.  The list separator for
      the options can now be changed in the usual way.  Bug 68.

JH/10 The smtp_receive_timeout main option is now expanded before use.

JH/11 The incoming_interface log option now also enables logging of the
      local interface on delivery outgoing connections.

JH/12 The cutthrough-routing facility now supports multi-recipient mails,
      if the interface and destination host and port all match.

JH/13 Bug 344: The verify = reverse_host_lookup ACL condition now accepts a
      /defer_ok option.

JH/14 Bug 1573: The spam= ACL condition now additionally supports Rspamd.
      Patch from Andrew Lewis.

JH/15 Bug 670: The spamd_address main option (for the spam= ACL condition)
      now supports optional time-restrictions, weighting, and priority
      modifiers per server.  Patch originally by <rommer@active.by>.

JH/16 The spamd_address main option now supports a mixed list of local
      and remote servers.  Remote servers can be IPv6 addresses, and
      specify a port-range.

JH/17 Bug 68: The spamd_address main option now supports an optional
      timeout value per server.

JH/18 Bug 1581: Router and transport options headers_add/remove can
      now have the list separator specified.

JH/19 Bug 392: spamd_address, and clamd av_scanner, now support retry
      option values.

JH/20 Bug 1571: Ensure that $tls_in_peerdn is set, when verification fails
      under OpenSSL.

JH/21 Support for the A6 type of dns record is withdrawn.

JH/22 Bug 608: The result of a QUIT or not-QUIT toplevel ACL now matters
      rather than the verbs used.

JH/23 Bug 1572: Increase limit on SMTP confirmation message copy size
      from 255 to 1024 chars.

JH/24 Verification callouts now attempt to use TLS by default.

HS/01 DNSSEC options (dnssec_require_domains, dnssec_request_domains)
      are generic router options now. The defaults didn't change.

JH/25 Bug 466: Add RFC2322 support for MIME attachment filenames.
      Original patch from Alexander Shikoff, worked over by JH.

HS/02 Bug 1575: exigrep falls back to autodetection of compressed
      files if ZCAT_COMMAND is not executable.

JH/26 Bug 1539: Add timeout/retry options on dnsdb lookups.

JH/27 Bug 286: Support SOA lookup in dnsdb lookups.

JH/28 Bug 1588: Do not use the A lookup following an AAAA for setting the FQDN.
      Normally benign, it bites when the pair was led to by a CNAME;
      modern usage is to not canonicalize the domain to a CNAME target
      (and we were inconsistent anyway for A-only vs AAAA+A).

JH/29 Bug 1632: Removed the word "rejected" from line logged for ACL discards.

JH/30 Check the forward DNS lookup for DNSSEC, in addition to the reverse,
      when evaluating $sender_host_dnssec.

JH/31 Check the HELO verification lookup for DNSSEC, adding new
      $sender_helo_dnssec variable.

JH/32 Bug 1397: Enable ECDHE on OpenSSL, just the NIST P-256 curve.

JH/33 Bug 1346: Note MAIL cmd seen in -bS batch, to avoid smtp_no_mail log.

JH/34 Bug 1648: Fix a memory leak seen with "mailq" and large queues.

JH/35 Bug 1642: Fix support of $spam_ variables at delivery time.  Was
      documented as working, but never had.  Support all but $spam_report.

JH/36 Bug 1659: Guard checking of input smtp commands again pseudo-command
      added for tls authenticator.

HS/03 Add perl_taintmode main config option


Exim version 4.85
-----------------

TL/01 When running the test suite, the README says that variables such as
      no_msglog_check are global and can be placed anywhere in a specific
      test's script, however it was observed that placement needed to be near
      the beginning for it to behave that way. Changed the runtest perl
      script to read through the entire script once to detect and set these
      variables, reset to the beginning of the script, and then run through
      the script parsing/test process like normal.

TL/02 The BSD's have an arc4random API. One of the functions to induce
      adding randomness was arc4random_stir(), but it has been removed in
      OpenBSD 5.5. Detect this OpenBSD version and skip calling this
      function when detected.

JH/01 Expand the EXPERIMENTAL_TPDA feature.  Several different events now
      cause callback expansion.

TL/03 Bugzilla 1518: Clarify "condition" processing in routers; that
      syntax errors in an expansion can be treated as a string instead of
      logging or causing an error, due to the internal use of bool_lax
      instead of bool when processing it.

JH/02 Add EXPERIMENTAL_DANE, allowing for using the DNS as trust-anchor for
      server certificates when making smtp deliveries.

JH/03 Support secondary-separator specifier for MX, SRV, TLSA lookups.

JH/04 Add ${sort {list}{condition}{extractor}} expansion item.

TL/04 Bugzilla 1216: Add -M (related messages) option to exigrep.

TL/05 GitHub Issue 18: Adjust logic testing for true/false in redis lookups.
      Merged patch from Sebastian Wiedenroth.

JH/05 Fix results-pipe from transport process.  Several recipients, combined
      with certificate use, exposed issues where response data items split
      over buffer boundaries were not parsed properly.  This eventually
      resulted in duplicates being sent.  This issue only became common enough
      to notice due to the introduction of connection certificate information,
      the item size being so much larger.  Found and fixed by Wolfgang Breyha.

JH/06 Bug 1533: Fix truncation of items in headers_remove lists.  A fixed
      size buffer was used, resulting in syntax errors when an expansion
      exceeded it.

JH/07 Add support for directories of certificates when compiled with a GnuTLS
      version 3.3.6 or later.

JH/08 Rename the TPDA experimental facility to Event Actions.  The #ifdef
      is EXPERIMENTAL_EVENT, the main-configuration and transport options
      both become "event_action", the variables become $event_name, $event_data
      and $event_defer_errno.  There is a new variable $verify_mode, usable in
      routers, transports and related events.  The tls:cert event is now also
      raised for inbound connections, if the main configuration event_action
      option is defined.

TL/06 In test suite, disable OCSP for old versions of openssl which contained
      early OCSP support, but no stapling (appears to be less than 1.0.0).

JH/09 When compiled with OpenSSL and EXPERIMENTAL_CERTNAMES, the checks on
      server certificate names available under the smtp transport option
      "tls_verify_cert_hostname" now do not permit multi-component wildcard
      matches.

JH/10 Time-related extraction expansions from certificates now use the main
      option "timezone" setting for output formatting, and are consistent
      between OpenSSL and GnuTLS compilations.  Bug 1541.

JH/11 Fix a crash in mime ACL when meeting a zero-length, quoted or RFC2047-
      encoded parameter in the incoming message.  Bug 1558.

JH/12 Bug 1527: Autogrow buffer used in reading spool files.  Since they now
      include certificate info, eximon was claiming there were spoolfile
      syntax errors.

JH/13 Bug 1521: Fix ldap lookup for single-attr request, multiple-attr return.

JH/14 Log delivery-related information more consistently, using the sequence
      "H=<name> [<ip>]" wherever possible.

TL/07 Bug 1547: Omit RFCs from release. Draft and RFCs have licenses which
      are problematic for Debian distribution, omit them from the release
      tarball.

JH/15 Updates and fixes to the EXPERIMENTAL_DSN feature.

JH/16 Fix string representation of time values on 64bit time_t architectures.
      Bug 1561.

JH/17 Fix a null-indirection in certextract expansions when a nondefault
      output list separator was used.


Exim version 4.84
-----------------
TL/01 Bugzilla 1506: Re-add a 'return NULL' to silence complaints from static
      checkers that were complaining about end of non-void function with no
      return.

JH/01 Bug 1513: Fix parsing of quoted parameter values in MIME headers.
      This was a regression introduced in 4.83 by another bugfix.

JH/02 Fix broken compilation when EXPERIMENTAL_DSN is enabled.

TL/02 Bug 1509: Fix exipick for enhanced spoolfile specification used when
      EXPERIMENTAL_DSN is enabled.  Fix from Wolfgang Breyha.


Exim version 4.83
-----------------

TF/01 Correctly close the server side of TLS when forking for delivery.

      When a message was received over SMTP with TLS, Exim failed to clear up
      the incoming connection properly after forking off the child process to
      deliver the message. In some situations the subsequent outgoing
      delivery connection happened to have the same fd number as the incoming
      connection previously had. Exim would try to use TLS and fail, logging
      a "Bad file descriptor" error.

TF/02 Portability fix for building lookup modules on Solaris when the xpg4
      utilities have not been installed.

JH/01 Fix memory-handling in use of acl as a conditional; avoid free of
      temporary space as the ACL may create new global variables.

TL/01 LDAP support uses per connection or global context settings, depending
      upon the detected version of the libraries at build time.

TL/02 Experimental Proxy Protocol support: allows a proxied SMTP connection
      to extract and use the src ip:port in logging and expansions as if it
      were a direct connection from the outside internet. PPv2 support was
      updated based on HAProxy spec change in May 2014.

JH/02 Add ${listextract {number}{list}{success}{fail}}.

TL/03 Bugzilla 1433: Fix DMARC SEGV with specific From header contents.
      Properly escape header and check for NULL return.

PP/01 Continue incomplete 4.82 PP/19 by fixing docs too: use dns_dnssec_ok
      not dns_use_dnssec.

JH/03 Bugzilla 1157: support log_selector smtp_confirmation for lmtp.

TL/04 Add verify = header_names_ascii check to reject email with non-ASCII
      characters in header names, implemented as a verify condition.
      Contributed by Michael Fischer v. Mollard.

TL/05 Rename SPF condition results err_perm and err_temp to standardized
      results permerror and temperror.  Previous values are deprecated but
      still accepted.  In a future release, err_perm and err_temp will be
      completely removed, which will be a backward incompatibility if the
      ACL tests for either of these two old results. Patch contributed by
      user bes-internal on the mailing list.

JH/04 Add ${utf8clean:} operator. Contributed by Alex Rau.

JH/05 Bugzilla 305: Log incoming-TLS details on rejects, subject to log
      selectors, in both main and reject logs.

JH/06 Log outbound-TLS and port details, subject to log selectors, for a
      failed delivery.

JH/07 Add malware type "sock" for talking to simple daemon.

JH/08 Bugzilla 1371: Add tls_{,try_}verify_hosts to smtp transport.

JH/09 Bugzilla 1431: Support (with limitations) headers_add/headers_remove in
      routers/transports under cutthrough routing.

JH/10 Bugzilla 1005: ACL "condition =" should accept values which are negative
      numbers.  Touch up "bool" conditional to keep the same definition.

TL/06 Remove duplicated language in spec file from 4.82 TL/16.

JH/11 Add dnsdb tlsa lookup.  From Todd Lyons.

JH/12 Expand items in router/transport headers_add or headers_remove lists
      individually rather than the list as a whole.  Bug 1452.

      Required for reasonable handling of multiple headers_ options when
      they may be empty; requires that headers_remove items with embedded
      colons must have them doubled (or the list-separator changed).

TL/07 Add new dmarc expansion variable $dmarc_domain_policy to directly
      view the policy declared in the DMARC record. Currently, $dmarc_status
      is a combined value of both the record presence and the result of the
      analysis.

JH/13 Fix handling of $tls_cipher et.al. in (non-verify) transport.  Bug 1455.

JH/14 New options dnssec_request_domains, dnssec_require_domains on the
      dnslookup router and the smtp transport (applying to the forward
      lookup).

TL/08 Bugzilla 1453: New LDAP "SERVERS=" option allows admin to override list
      of ldap servers used for a specific lookup.  Patch provided by Heiko
      Schlichting.

JH/18 New options dnssec_lax, dnssec_strict on dnsdb lookups.
      New variable $lookup_dnssec_authenticated for observability.

TL/09 Bugzilla 609: Add -C option to exiqgrep, specify which exim.conf to use.
      Patch submitted by Lars Timman.

JH/19 EXPERIMENTAL_OCSP support under GnuTLS.  Bug 1459.

TL/10 Bugzilla 1454: New -oMm option to pass message reference to Exim.
      Requires trusted mode and valid format message id, aborts otherwise.
      Patch contributed by Heiko Schlichting.

JH/20 New expansion variables tls_(in,out)_(our,peer)cert, and expansion item
      certextract with support for various fields.  Bug 1358.

JH/21 Observability of OCSP via variables tls_(in,out)_ocsp.  Stapling
      is requested by default, modifiable by smtp transport option
      hosts_request_ocsp.

JH/22 Expansion operators ${md5:string} and ${sha1:string} can now
      operate on certificate variables to give certificate fingerprints
      Also new ${sha256:cert_variable}.

JH/23 The PRDR feature is moved from being Experimental into the mainline.

TL/11 Bug 1119: fix memory allocation in string_printing2().  Patch from
      Christian Aistleitner.

JH/24 The OCSP stapling feature is moved from Experimental into the mainline.

TL/12 Bug 1444: Fix improper \r\n sequence handling when writing spool
      file.  Patch from Wolfgang Breyha.

JH/25 Expand the coverage of the delivery $host and $host_address to
      client authenticators run in verify callout.  Bug 1476.

JH/26 Port service names are now accepted for tls_on_connect_ports, to
      align with daemon_smtp_ports.  Bug 72.

TF/03 Fix udpsend. The ip_connectedsocket() function's socket type
      support and error reporting did not work properly.

TL/13 Bug 1495: Exiqgrep check if -C config file specified on cli exists
      and is readable.  Patch from Andrew Colin Kissa.

TL/14 Enhance documentation of ${run expansion and how it parses the
      commandline after expansion, particularly in the case when an
      unquoted variable expansion results in an empty value.

JH/27 The TLS SNI feature was broken in 4.82.  Fix it.

PP/02 Fix internal collision of T_APL on systems which support RFC3123
      by renaming away from it.  Addresses GH issue 15, reported by
      Jasper Wallace.

JH/28 Fix parsing of MIME headers for parameters with quoted semicolons.

TL/15 SECURITY: prevent double expansion in math comparison functions
      (can expand unsanitized data). Not remotely exploitable.
      CVE-2014-2972


Exim version 4.82
-----------------

PP/01 Add -bI: framework, and -bI:sieve for querying sieve capabilities.

PP/02 Make -n do something, by making it not do something.
      When combined with -bP, the name of an option is not output.

PP/03 Added tls_dh_min_bits SMTP transport driver option, only honoured
      by GnuTLS.

PP/04 First step towards DNSSEC, provide $sender_host_dnssec for
      $sender_host_name and config options to manage this, and basic check
      routines.

PP/05 DSCP support for outbound connections and control modifier for inbound.

PP/06 Cyrus SASL: set local and remote IP;port properties for driver.
      (Only plugin which currently uses this is kerberos4, which nobody should
      be using, but we should make it available and other future plugins might
      conceivably use it, even though it would break NAT; stuff *should* be
      using channel bindings instead).

PP/07 Handle "exim -L <tag>" to indicate to use syslog with tag as the process
      name; added for Sendmail compatibility; requires admin caller.
      Handle -G as equivalent to "control = suppress_local_fixups" (we used to
      just ignore it); requires trusted caller.
      Also parse but ignore: -Ac -Am -X<logfile>
      Bugzilla 1117.

TL/01 Bugzilla 1258 - Refactor MAIL FROM optional args processing.

TL/02 Add +smtp_confirmation as a default logging option.

TL/03 Bugzilla 198 - Implement remove_header ACL modifier.
      Patch by Magnus Holmgren from 2007-02-20.

TL/04 Bugzilla 1281 - Spec typo.
      Bugzilla 1283 - Spec typo.
      Bugzilla 1290 - Spec grammar fixes.

TL/05 Bugzilla 1285 - Spec omission, fix docbook errors for spec.txt creation.

TL/06 Add Experimental DMARC support using libopendmarc libraries.

TL/07 Fix an out of order global option causing a segfault.  Reported to dev
      mailing list by by Dmitry Isaikin.

JH/01 Bugzilla 1201 & 304 - New cutthrough-delivery feature, with TLS support.

JH/02 Support "G" suffix to numbers in ${if comparisons.

PP/08 Handle smtp transport tls_sni option forced-fail for OpenSSL.

NM/01 Bugzilla 1197 - Spec typo
      Bugzilla 1196 - Spec examples corrections

JH/03 Add expansion operators ${listnamed:name} and ${listcount:string}

PP/09 Add gnutls_allow_auto_pkcs11 option (was originally called
      gnutls_enable_pkcs11, but renamed to more accurately indicate its
      function.

PP/10 Let Linux makefile inherit CFLAGS/CFLAGS_DYNAMIC.
      Pulled from Debian 30_dontoverridecflags.dpatch by Andreas Metzler.

JH/04 Add expansion item ${acl {name}{arg}...}, expansion condition
      "acl {{name}{arg}...}", and optional args on acl condition
      "acl = name arg..."

JH/05 Permit multiple router/transport headers_add/remove lines.

JH/06 Add dnsdb pseudo-lookup "a+" to do an "aaaa" + "a" combination.

JH/07 Avoid using a waiting database for a single-message-only transport.
      Performance patch from Paul Fisher.  Bugzilla 1262.

JH/08 Strip leading/trailing newlines from add_header ACL modifier data.
      Bugzilla 884.

JH/09 Add $headers_added variable, with content from use of ACL modifier
      add_header (but not yet added to the message).  Bugzilla 199.

JH/10 Add 8bitmime log_selector, for 8bitmime status on the received line.
      Pulled from Bugzilla 817 by Wolfgang Breyha.

PP/11 SECURITY: protect DKIM DNS decoding from remote exploit.
      CVE-2012-5671
      (nb: this is the same fix as in Exim 4.80.1)

JH/11 Add A= logging on delivery lines, and a client_set_id option on
      authenticators.

JH/12 Add optional authenticated_sender logging to A= and a log_selector
      for control.

PP/12 Unbreak server_set_id for NTLM/SPA auth, broken by 4.80 PP/29.

PP/13 Dovecot auth: log better reason to rejectlog if Dovecot did not
      advertise SMTP AUTH mechanism to us, instead of a generic
      protocol violation error.  Also, make Exim more robust to bad
      data from the Dovecot auth socket.

TF/01 Fix ultimate retry timeouts for intermittently deliverable recipients.

      When a queue runner is handling a message, Exim first routes the
      recipient addresses, during which it prunes them based on the retry
      hints database. After that it attempts to deliver the message to
      any remaining recipients. It then updates the hints database using
      the retry rules.

      So if a recipient address works intermittently, it can get repeatedly
      deferred at routing time. The retry hints record remains fresh so the
      address never reaches the final cutoff time.

      This is a fairly common occurrence when a user is bumping up against
      their storage quota. Exim had some logic in its local delivery code
      to deal with this. However it did not apply to per-recipient defers
      in remote deliveries, e.g. over LMTP to a separate IMAP message store.

      This change adds a proper retry rule check during routing so that the
      final cutoff time is checked against the message's age. We only do
      this check if there is an address retry record and there is not a
      domain retry record; this implies that previous attempts to handle
      the address had the retry_use_local_parts option turned on. We use
      this as an approximation for the destination being like a local
      delivery, as in LMTP.

      I suspect this new check makes the old local delivery cutoff check
      redundant, but I have not verified this so I left the code in place.

TF/02 Correct gecos expansion when From: is a prefix of the username.

      Test 0254 submits a message to Exim with the header

        Resent-From: f

      When I ran the test suite under the user fanf2, Exim expanded
      the header to contain my full name, whereas it should have added
      a Resent-Sender: header. It erroneously treats any prefix of the
      username as equal to the username.

      This change corrects that bug.

GF/01 DCC debug and logging tidyup
      Error conditions log to paniclog rather than rejectlog.
      Debug lines prefixed by "DCC: " to remove any ambiguity.

TF/03 Avoid unnecessary rebuilds of lookup-related code.

PP/14 Fix OCSP reinitialisation in SNI handling for Exim/TLS as server.
      Bug spotted by Jeremy Harris; was flawed since initial commit.
      Would have resulted in OCSP responses post-SNI triggering an Exim
      NULL dereference and crash.

JH/13 Add $router_name and $transport_name variables.  Bugzilla 308.

PP/15 Define SIOCGIFCONF_GIVES_ADDR for GNU Hurd.
      Bug detection, analysis and fix by Samuel Thibault.
      Bugzilla 1331, Debian bug #698092.

SC/01 Update eximstats to watch out for senders sending 'HELO [IpAddr]'

JH/14 SMTP PRDR (http://www.eric-a-hall.com/specs/draft-hall-prdr-00.txt).
      Server implementation by Todd Lyons, client by JH.
      Only enabled when compiled with EXPERIMENTAL_PRDR.  A new
      config variable "prdr_enable" controls whether the server
      advertises the facility.  If the client requests PRDR a new
      acl_data_smtp_prdr ACL is called once for each recipient, after
      the body content is received and before the acl_smtp_data ACL.
      The client is controlled by both of: a hosts_try_prdr option
      on the smtp transport, and the server advertisement.
      Default client logging of deliveries and rejections involving
      PRDR are flagged with the string "PRDR".

PP/16 Fix problems caused by timeouts during quit ACLs trying to double
      fclose().  Diagnosis by Todd Lyons.

PP/17 Update configure.default to handle IPv6 localhost better.
      Patch by Alain Williams (plus minor tweaks).
      Bugzilla 880.

PP/18 OpenSSL made graceful with empty tls_verify_certificates setting.
      This is now consistent with GnuTLS, and is now documented: the
      previous undocumented portable approach to treating the option as
      unset was to force an expansion failure.  That still works, and
      an empty string is now equivalent.

PP/19 Renamed DNSSEC-enabling option to "dns_dnssec_ok", to make it
      clearer that Exim is using the DO (DNSSEC OK) EDNS0 resolver flag,
      not performing validation itself.

PP/20 Added force_command boolean option to pipe transport.
      Patch from Nick Koston, of cPanel Inc.

JH/15 AUTH support on callouts (and hence cutthrough-deliveries).
      Bugzilla 321, 823.

TF/04 Added udpsend ACL modifier and hexquote expansion operator

PP/21 Fix eximon continuous updating with timestamped log-files.
      Broken in a format-string cleanup in 4.80, missed when I repaired the
      other false fix of the same issue.
      Report and fix from Heiko Schlichting.
      Bugzilla 1363.

PP/22 Guard LDAP TLS usage against Solaris LDAP variant.
      Report from Prashanth Katuri.

PP/23 Support safari_ecdhe_ecdsa_bug for openssl_options.
      It's SecureTransport, so affects any MacOS clients which use the
      system-integrated TLS libraries, including email clients.

PP/24 Fix segfault from trying to fprintf() to a NULL stdio FILE* if
      using a MIME ACL for non-SMTP local injection.
      Report and assistance in diagnosis by Warren Baker.

TL/08 Adjust exiqgrep to be case-insensitive for sender/receiver.

JH/16 Fix comparisons for 64b.  Bugzilla 1385.

TL/09 Add expansion variable $authenticated_fail_id to keep track of
      last id that failed so it may be referenced in subsequent ACL's.

TL/10 Bugzilla 1375 - Prevent TLS rebinding in ldap. Patch provided by
      Alexander Miroch.

TL/11 Bugzilla 1382 - Option ldap_require_cert overrides start_tls
      ldap library initialization, allowing self-signed CA's to be
      used. Also properly sets require_cert option later in code by
      using NULL (global ldap config) instead of ldap handle (per
      session). Bug diagnosis and testing by alxgomz.

TL/12 Enhanced documentation in the ratelimit.pl script provided in
      the src/util/ subdirectory.

TL/13 Bug 1031 - Imported transport SQL logging patch from Axel Rau
      renamed to Transport Post Delivery Action by Jeremy Harris, as
      EXPERIMENTAL_TPDA.

TL/14 Bugzilla 1217 - Redis lookup support has been added. It is only enabled
      when Exim is compiled with EXPERIMENTAL_REDIS. A new config variable
      redis_servers = needs to be configured which will be used by the redis
      lookup.  Patch from Warren Baker, of The Packet Hub.

TL/15 Fix exiqsumm summary for corner case. Patch provided by Richard Hall.

TL/16 Bugzilla 1289 - Clarify host/ip processing when have errors looking up a
      hostname or reverse DNS when processing a host list. Used suggestions
      from multiple comments on this bug.

TL/17 Bugzilla 1057 - Multiple clamd TCP targets patch from Mark Zealey.

TL/18 Had previously added a -CONTINUE option to runtest in the test suite.
      Missed a few lines, added it to make the runtest require no keyboard
      interaction.

TL/19 Bugzilla 1402 - Test 533 fails if any part of the path to the test suite
      contains upper case chars. Make router use caseful_local_part.

TL/20 Bugzilla 1400 - Add AVOID_GNUTLS_PKCS11 build option. Allows GnuTLS
      support when GnuTLS has been built with p11-kit.


Exim version 4.80.1
-------------------

PP/01 SECURITY: protect DKIM DNS decoding from remote exploit.
      CVE-2012-5671
      This, or similar/improved, will also be change PP/11 of 4.82.


Exim version 4.80
-----------------

PP/01 Handle short writes when writing local log-files.
      In practice, only affects FreeBSD (8 onwards).
      Bugzilla 1053, with thanks to Dmitry Isaikin.

NM/01 Bugzilla 949 - Documentation tweak

NM/02 Bugzilla 1093 - eximstats DATA reject detection regexps
      improved.

NM/03 Bugzilla 1169 - primary_hostname spelling was incorrect in docs.

PP/02 Implemented gsasl authenticator.

PP/03 Implemented heimdal_gssapi authenticator with "server_keytab" option.

PP/04 Local/Makefile support for (AUTH|LOOKUP)_*_PC=foo to use
      `pkg-config foo` for cflags/libs.

PP/05 Swapped $auth1/$auth2 for gsasl GSSAPI mechanism, to be more consistent
      with rest of GSASL and with heimdal_gssapi.

PP/06 Local/Makefile support for USE_(GNUTLS|OPENSSL)_PC=foo to use
      `pkg-config foo` for cflags/libs for the TLS implementation.

PP/07 New expansion variable $tls_bits; Cyrus SASL server connection
      properties get this fed in as external SSF.  A number of robustness
      and debugging improvements to the cyrus_sasl authenticator.

PP/08 cyrus_sasl server now expands the server_realm option.

PP/09 Bugzilla 1214 - Log authentication information in reject log.
      Patch by Jeremy Harris.

PP/10 Added dbmjz lookup type.

PP/11 Let heimdal_gssapi authenticator take a SASL message without an authzid.

PP/12 MAIL args handles TAB as well as SP, for better interop with
      non-compliant senders.
      Analysis and variant patch by Todd Lyons.

NM/04 Bugzilla 1237 - fix cases where printf format usage not indicated
      Bug report from Lars Müller <lars@samba.org> (via SUSE),
      Patch from Dirk Mueller <dmueller@suse.com>

PP/13 tls_peerdn now print-escaped for spool files.
      Observed some $tls_peerdn in wild which contained \n, which resulted
      in spool file corruption.

PP/14 TLS fixes for OpenSSL: support TLS 1.1 & 1.2; new "openssl_options"
      values; set SSL_MODE_AUTO_RETRY so that OpenSSL will retry a read
      or write after TLS renegotiation, which otherwise led to messages
      "Got SSL error 2".

TK/01 Bugzilla 1239 - fix DKIM verification when signature was not inserted
      as a tracking header (ie: a signed header comes before the signature).
      Patch from Wolfgang Breyha.

JH/01 Bugzilla 660 - Multi-valued attributes from ldap now parseable as a
      comma-sep list; embedded commas doubled.

JH/02 Refactored ACL "verify =" logic to table-driven dispatch.

PP/15 LDAP: Check for errors of TLS initialisation, to give correct
      diagnostics.
      Report and patch from Dmitry Banschikov.

PP/16 Removed "dont_insert_empty_fragments" from "openssl_options".
      Removed SSL_clear() after SSL_new() which led to protocol negotiation
      failures.  We appear to now support TLS1.1+ with Exim.

PP/17 OpenSSL: new expansion var $tls_sni, which if used in tls_certificate
      lets Exim select keys and certificates based upon TLS SNI from client.
      Also option tls_sni on SMTP Transports.  Also clear $tls_bits correctly
      before an outbound SMTP session.  New log_selector, +tls_sni.

PP/18 Bugzilla 1122 - check localhost_number expansion for failure, avoid
      NULL dereference.  Report and patch from Alun Jones.

PP/19 DNS resolver init changes for NetBSD compatibility.  (Risk of breakage
      on less well tested platforms).  Obviates NetBSD pkgsrc patch-ac.
      Not seeing resolver debug output on NetBSD, but suspect this is a
      resolver implementation change.

PP/20 Revert part of NM/04, it broke log_path containing %D expansions.
      Left warnings.  Added "eximon gdb" invocation mode.

PP/21 Defaulting "accept_8bitmime" to true, not false.

PP/22 Added -bw for inetd wait mode support.

PP/23 Added PCRE_CONFIG=yes support to Makefile for using pcre-config to
      locate the relevant includes and libraries.  Made this the default.

PP/24 Fixed headers_only on smtp transports (was not sending trailing dot).
      Bugzilla 1246, report and most of solution from Tomasz Kusy.

JH/03 ${eval } now uses 64-bit and supports a "g" suffix (like to "k" and "m").
      This may cause build issues on older platforms.

PP/25 Revamped GnuTLS support, passing tls_require_ciphers to
      gnutls_priority_init, ignoring Exim options gnutls_require_kx,
      gnutls_require_mac & gnutls_require_protocols (no longer supported).
      Added SNI support via GnuTLS too.
      Made ${randint:..} supplier available, if using not-too-old GnuTLS.

PP/26 Added EXPERIMENTAL_OCSP for OpenSSL.

PP/27 Applied dnsdb SPF support patch from Janne Snabb.
      Applied second patch from Janne, implementing suggestion to default
      multiple-strings-in-record handling to match SPF spec.

JH/04 Added expansion variable $tod_epoch_l for a higher-precision time.

PP/28 Fix DCC dcc_header content corruption (stack memory referenced,
      read-only, out of scope).
      Patch from Wolfgang Breyha, report from Stuart Northfield.

PP/29 Fix three issues highlighted by clang analyser static analysis.
      Only crash-plausible issue would require the Cambridge-specific
      iplookup router and a misconfiguration.
      Report from Marcin Mirosław.

PP/30 Another attempt to deal with PCRE_PRERELEASE, this one less buggy.

PP/31 %D in printf continues to cause issues (-Wformat=security), so for
      now guard some of the printf checks behind WANT_DEEPER_PRINTF_CHECKS.
      As part of this, removing so much warning spew let me fix some minor
      real issues in debug logging.

PP/32 GnuTLS was always using default tls_require_ciphers, due to a missing
      assignment on my part.  Fixed.

PP/33 Added tls_dh_max_bits option, defaulting to current hard-coded limit
      of NSS, for GnuTLS/NSS interop.  Problem root cause diagnosis by
      Janne Snabb (who went above and beyond: thank you).

PP/34 Validate tls_require_ciphers on startup, since debugging an invalid
      string otherwise requires a connection and a bunch more work and it's
      relatively easy to get wrong.  Should also expose TLS library linkage
      problems.

PP/35 Pull in <features.h> on Linux, for some portability edge-cases of
      64-bit ${eval} (JH/03).

PP/36 Define _GNU_SOURCE in exim.h; it's needed for some releases of
      GNU libc to support some of the 64-bit stuff, should not lead to
      conflicts.  Defined before os.h is pulled in, so if a given platform
      needs to override this, it can.

PP/37 Unbreak Cyrus SASL auth: SSF retrieval was incorrect, Exim thought
      protection layer was required, which is not implemented.
      Bugzilla 1254, patch from Wolfgang Breyha.

PP/38 Overhaul DH prime handling, supply RFC-specified DH primes as built
      into Exim, default to IKE id 23 from RFC 5114 (2048 bit).  Make
      tls_dhparam take prime identifiers.  Also unbreak combination of
      OpenSSL+DH_params+TLSSNI.

PP/39 Disable SSLv2 by default in OpenSSL support.


Exim version 4.77
-----------------

PP/01 Solaris build fix for Oracle's LDAP libraries.
      Bugzilla 1109, patch from Stephen Usher.

TF/01 HP/UX build fix: avoid arithmetic on a void pointer.

TK/01 DKIM Verification: Fix relaxed canon for empty headers w/o
      whitespace trailer

TF/02 Fix a couple more cases where we did not log the error message
      when unlink() failed. See also change 4.74-TF/03.

TF/03 Make the exiwhat support code safe for signals. Previously Exim might
      lock up or crash if it happened to be inside a call to libc when it
      got a SIGUSR1 from exiwhat.

      The SIGUSR1 handler appends the current process status to the process
      log which is later printed by exiwhat. It used to use the general
      purpose logging code to do this, but several functions it calls are
      not safe for signals.

      The new output code in the SIGUSR1 handler is specific to the process
      log, and simple enough that it's easy to inspect for signal safety.
      Removing some special cases also simplifies the general logging code.
      Removing the spurious timestamps from the process log simplifies
      exiwhat.

TF/04 Improved ratelimit ACL condition.

      The /noupdate option has been deprecated in favour of /readonly which
      has clearer semantics. The /leaky, /strict, and /readonly update modes
      are mutually exclusive. The update mode is no longer included in the
      database key; it just determines when the database is updated. (This
      means that when you upgrade Exim will forget old rate measurements.)

      Exim now checks that the per_* options are used with an update mode that
      makes sense for the current ACL. For example, when Exim is processing a
      message (e.g. acl_smtp_rcpt or acl_smtp_data, etc.) you can specify
      per_mail/leaky or per_mail/strict; otherwise (e.g. in acl_smtp_helo) you
      must specify per_mail/readonly. If you omit the update mode it defaults to
      /leaky where that makes sense (as before) or /readonly where required.

      The /noupdate option is now undocumented but still supported for
      backwards compatibility. It is equivalent to /readonly except that in
      ACLs where /readonly is required you may specify /leaky/noupdate or
      /strict/noupdate which are treated the same as /readonly.

      A useful new feature is the /count= option. This is a generalization
      of the per_byte option, so that you can measure the throughput of other
      aggregate values. For example, the per_byte option is now equivalent
      to per_mail/count=${if >{0}{$message_size} {0} {$message_size} }.

      The per_rcpt option has been generalized using the /count= mechanism
      (though it's more complicated than the per_byte equivalence). When it is
      used in acl_smtp_rcpt, the per_rcpt option adds recipients to the
      measured rate one at a time; if it is used later (e.g. in acl_smtp_data)
      or in a non-SMTP ACL it adds all the recipients in one go. (The latter
      /count=$recipients_count behaviour used to work only in non-SMTP ACLs.)
      Note that using per_rcpt with a non-readonly update mode in more than
      one ACL will cause the recipients to be double-counted. (The per_mail
      and per_byte options don't have this problem.)

      The handling of very low rates has changed slightly. If the computed rate
      is less than the event's count (usually one) then this event is the first
      after a long gap. In this case the rate is set to the same as this event's
      count, so that the first message of a spam run is counted properly.

      The major new feature is a mechanism for counting the rate of unique
      events. The new per_addr option counts the number of different
      recipients that someone has sent messages to in the last time period. It
      behaves like per_rcpt if all the recipient addresses are different, but
      duplicate recipient addresses do not increase the measured rate. Like
      the /count= option this is a general mechanism, so the per_addr option
      is equivalent to per_rcpt/unique=$local_part@$domain. You can, for
      example, measure the rate that a client uses different sender addresses
      with the options per_mail/unique=$sender_address. There are further
      details in the main documentation.

TF/05 Removed obsolete $Cambridge$ CVS revision strings.

TF/06 Removed a few PCRE remnants.

TF/07 Automatically extract Exim's version number from tags in the git
      repository when doing development or release builds.

PP/02 Raise smtp_cmd_buffer_size to 16kB.
      Bugzilla 879.  Patch from Paul Fisher.

PP/03 Implement SSL-on-connect outbound with protocol=smtps on smtp transport.
      Heavily based on revision 40f9a89a from Simon Arlott's tree.
      Bugzilla 97.

PP/04 Use .dylib instead of .so for dynamic library loading on MacOS.

PP/05 Variable $av_failed, true if the AV scanner deferred.
      Bugzilla 1078.  Patch from John Horne.

PP/06 Stop make process more reliably on build failure.
      Bugzilla 1087.  Patch from Heiko Schlittermann.

PP/07 Make maildir_use_size_file an _expandable_ boolean.
      Bugzilla 1089.  Patch from Heiko Schlittermann.

PP/08 Handle ${run} returning more data than OS pipe buffer size.
      Bugzilla 1131.  Patch from Holger Weiß.

PP/09 Handle IPv6 addresses with SPF.
      Bugzilla 860.  Patch from Wolfgang Breyha.

PP/10 GnuTLS: support TLS 1.2 & 1.1.
      Bugzilla 1156.
      Use gnutls_certificate_verify_peers2() [patch from Andreas Metzler].
      Bugzilla 1095.

PP/11 match_* no longer expand right-hand-side by default.
      New compile-time build option, EXPAND_LISTMATCH_RHS.
      New expansion conditions, "inlist", "inlisti".

PP/12 fix uninitialised greeting string from PP/03 (smtps client support).

PP/13 shell and compiler warnings fixes for RC1-RC4 changes.

PP/14 fix log_write() format string regression from TF/03.
      Bugzilla 1152.  Patch from Dmitry Isaikin.


Exim version 4.76
-----------------

PP/01 The new ldap_require_cert option would segfault if used.  Fixed.

PP/02 Harmonised TLS library version reporting; only show if debugging.
      Layout now matches that introduced for other libraries in 4.74 PP/03.

PP/03 New openssl_options items: no_sslv2 no_sslv3 no_ticket no_tlsv1

PP/04 New "dns_use_edns0" global option.

PP/05 Don't segfault on misconfiguration of ref:name exim-user as uid.
      Bugzilla 1098.

PP/06 Extra paranoia around buffer usage at the STARTTLS transition.
      nb: Exim is not vulnerable to http://www.kb.cert.org/vuls/id/555316

TK/01 Updated PolarSSL code to 0.14.2.
      Bugzilla 1097. Patch from Andreas Metzler.

PP/07 Catch divide-by-zero in ${eval:...}.
      Fixes bugzilla 1102.

PP/08 Condition negation of bool{}/bool_lax{} did not negate.  Fixed.
      Bugzilla 1104.

TK/02 Bugzilla 1106: CVE-2011-1764 - DKIM log line was subject to a
      format-string attack -- SECURITY: remote arbitrary code execution.

TK/03 SECURITY - DKIM signature header parsing was double-expanded, second
      time unintentionally subject to list matching rules, letting the header
      cause arbitrary Exim lookups (of items which can occur in lists, *not*
      arbitrary string expansion). This allowed for information disclosure.

PP/09 Fix another SIGFPE (x86) in ${eval:...} expansion, this time related to
      INT_MIN/-1 -- value coerced to INT_MAX.


Exim version 4.75
-----------------

NM/01 Workaround for PCRE version dependency in version reporting
      Bugzilla 1073

TF/01 Update valgrind.h and memcheck.h to copies from valgrind-3.6.0.
      This fixes portability to compilers other than gcc, notably
      Solaris CC and HP-UX CC. Fixes Bugzilla 1050.

TF/02 Bugzilla 139: Avoid using the += operator in the modular lookup
      makefiles for portability to HP-UX and POSIX correctness.

PP/01 Permit LOOKUP_foo enabling on the make command-line.
      Also via indented variable definition in the Makefile.
      (Debugging by Oliver Heesakkers).

PP/02 Restore caching of spamd results with expanded spamd_address.
      Patch from author of expandable spamd_address patch, Wolfgang Breyha.

PP/03 Build issue: lookups-Makefile now exports LC_ALL=C
      Improves build reliability.  Fix from: Frank Elsner

NM/02 Fix wide character breakage in the rfc2047 coding
      Fixes bug 1064. Patch from Andrey N. Oktyabrski

NM/03 Allow underscore in dnslist lookups
      Fixes bug 1026. Patch from Graeme Fowler

PP/04 Bugzilla 230: Support TLS-enabled LDAP (in addition to ldaps).
      Code patches from Adam Ciarcinski of NetBSD.

NM/04 Fixed exiqgrep to cope with mailq missing size issue
      Fixes bug 943.

PP/05 Bugzilla 1083: when lookup expansion defers, escape the output which
      is logged, to avoid truncation. Patch from John Horne.

PP/06 Bugzilla 1042: implement freeze_signal on pipe transports.
      Patch from Jakob Hirsch.

PP/07 Bugzilla 1061: restrict error messages sent over SMTP to not reveal
      SQL string expansion failure details.
      Patch from Andrey Oktyabrski.

PP/08 Bugzilla 486: implement %M datestamping in log filenames.
      Patch from Simon Arlott.

PP/09 New lookups functionality failed to compile on old gcc which rejects
      extern declarations in function scope.
      Patch from Oliver Fleischmann

PP/10 Use sig_atomic_t for flags set from signal handlers.
      Check getgroups() return and improve debugging.
      Fixed developed for diagnosis in bug 927 (which turned out to be
      a kernel bug).

PP/11 Bugzilla 1055: Update $message_linecount for maildir_tag.
      Patch from Mark Zealey.

PP/12 Bugzilla 1056: Improved spamd server selection.
      Patch from Mark Zealey.

PP/13 Bugzilla 1086: Deal with maildir quota file races.
      Based on patch from Heiko Schlittermann.

PP/14 Bugzilla 1019: DKIM multiple signature generation fix.
      Patch from Uwe Doering, sign-off by Michael Haardt.

NM/05 Fix to spam.c to accommodate older gcc versions which dislike
      variable declaration deep within a block.  Bug and patch from
      Dennis Davis.

PP/15 lookups-Makefile IRIX compatibility coercion.

PP/16 Make DISABLE_DKIM build knob functional.

NM/06 Bugzilla 968: child_open_uid: restore default SIGPIPE handler
      Patch by Simon Arlott

TF/03 Fix valgrind.h portability to C89 compilers that do not support
      variable argument macros. Our copy now differs from upstream.


Exim version 4.74
-----------------

TF/01 Failure to get a lock on a hints database can have serious
      consequences so log it to the panic log.

TF/02 Log LMTP confirmation messages in the same way as SMTP,
      controlled using the smtp_confirmation log selector.

TF/03 Include the error message when we fail to unlink a spool file.

DW/01 Bugzilla 139: Support dynamically loaded lookups as modules.
      With thanks to Steve Haslam, Johannes Berg & Serge Demonchaux
      for maintaining out-of-tree patches for some time.

PP/01 Bugzilla 139: Documentation and portability issues.
      Avoid GNU Makefile-isms, let Exim continue to build on BSD.
      Handle per-OS dynamic-module compilation flags.

PP/02 Let /dev/null have normal permissions.
      The 4.73 fixes were a little too stringent and complained about the
      permissions on /dev/null.  Exempt it from some checks.
      Reported by Andreas M. Kirchwitz.

PP/03 Report version information for many libraries, including
      Exim version information for dynamically loaded libraries.  Created
      version.h, now support a version extension string for distributors
      who patch heavily. Dynamic module ABI change.

PP/04 CVE-2011-0017 - check return value of setuid/setgid. This is a
      privilege escalation vulnerability whereby the Exim run-time user
      can cause root to append content of the attacker's choosing to
      arbitrary files.

PP/05 Bugzilla 1041: merged DCC maintainer's fixes for return code.
      (Wolfgang Breyha)

PP/06 Bugzilla 1071: fix delivery logging with untrusted macros.
      If dropping privileges for untrusted macros, we disabled normal logging
      on the basis that it would fail; for the Exim run-time user, this is not
      the case, and it resulted in successful deliveries going unlogged.
      Fixed.  Reported by Andreas Metzler.


Exim version 4.73
-----------------

PP/01 Date: & Message-Id: revert to normally being appended to a message,
      only prepend for the Resent-* case.  Fixes regression introduced in
      Exim 4.70 by NM/22 for Bugzilla 607.

PP/02 Include check_rfc2047_length in configure.default because we're seeing
      increasing numbers of administrators be bitten by this.

JJ/01 Added DISABLE_DKIM and comment to src/EDITME

PP/03 Bugzilla 994: added openssl_options main configuration option.

PP/04 Bugzilla 995: provide better SSL diagnostics on failed reads.

PP/05 Bugzilla 834: provide a permit_coredump option for pipe transports.

PP/06 Adjust NTLM authentication to handle SASL Initial Response.

PP/07 If TLS negotiated an anonymous cipher, we could end up with SSL but
      without a peer certificate, leading to a segfault because of an
      assumption that peers always have certificates.  Be a little more
      paranoid.  Problem reported by Martin Tscholak.

PP/08 Bugzilla 926: switch ClamAV to use the new zINSTREAM API for content
      filtering; old API available if built with WITH_OLD_CLAMAV_STREAM=yes
      NB: ClamAV planning to remove STREAM in "middle of 2010".
      CL also introduces -bmalware, various -d+acl logging additions and
      more caution in buffer sizes.

PP/09 Implemented reverse_ip expansion operator.

PP/10 Bugzilla 937: provide a "debug" ACL control.

PP/11 Bugzilla 922: Documentation dusting, patch provided by John Horne.

PP/12 Bugzilla 973: Implement --version.

PP/13 Bugzilla 752: Refuse to build/run if Exim user is root/0.

PP/14 Build without WITH_CONTENT_SCAN. Path from Andreas Metzler.

PP/15 Bugzilla 816: support multiple condition rules on Routers.

PP/16 Add bool_lax{} expansion operator and use that for combining multiple
      condition rules, instead of bool{}.  Make both bool{} and bool_lax{}
      ignore trailing whitespace.

JJ/02 prevent non-panic DKIM error from being sent to paniclog

JJ/03 added tcp_wrappers_daemon_name to allow host entries other than
      "exim" to be used

PP/17 Fix malware regression for cmdline scanner introduced in PP/08.
      Notification from Dr Andrew Aitchison.

PP/18 Change ClamAV response parsing to be more robust and to handle ClamAV's
      ExtendedDetectionInfo response format.
      Notification from John Horne.

PP/19 OpenSSL 1.0.0a compatibility const-ness change, should be backwards
      compatible.

PP/20 Added a CONTRIBUTING file.  Fixed the documentation build to use http:
      XSL and documented dependency on system catalogs, with examples of how
      it normally works.

DW/21 Added Valgrind hooks in store.c to help it capture out-of-bounds store
      access.

DW/22 Bugzilla 1044: CVE-2010-4345 - partial fix: restrict default behaviour
      of CONFIGURE_OWNER and CONFIGURE_GROUP options to no longer allow a
      configuration file which is writeable by the Exim user or group.

DW/23 Bugzilla 1044: CVE-2010-4345 - part two: extend checks for writeability
      of configuration files to cover files specified with the -C option if
      they are going to be used with root privileges, not just the default
      configuration file.

DW/24 Bugzilla 1044: CVE-2010-4345 - part three: remove ALT_CONFIG_ROOT_ONLY
      option (effectively making it always true).

DW/25 Add TRUSTED_CONFIG_PREFIX_FILE option to allow alternative configuration
      files to be used while preserving root privileges.

DW/26 Set FD_CLOEXEC on SMTP sockets after forking in the daemon, to ensure
      that rogue child processes cannot use them.

PP/27 Bugzilla 1047: change the default for system_filter_user to be the Exim
      run-time user, instead of root.

PP/28 Add WHITELIST_D_MACROS option to let some macros be overridden by the
      Exim run-time user without dropping privileges.

DW/29 Remove use of va_copy() which breaks pre-C99 systems. Duplicate the
      result string, instead of calling string_vformat() twice with the same
      arguments.

DW/30 Allow TRUSTED_CONFIG_PREFIX_FILE only for Exim or CONFIGURE_OWNER, not
      for other users. Others should always drop root privileges if they use
      -C on the command line, even for a whitelisted configure file.

DW/31 Turn TRUSTED_CONFIG_PREFIX_FILE into TRUSTED_CONFIG_FILE. No prefixes.

NM/01 Fixed bug #1002 - Message loss when using multiple deliveries


Exim version 4.72
-----------------

JJ/01 installed exipick 20100104.1, adding $max_received_linelength,
      $data_path, and $header_path variables; fixed documentation bugs and
      typos

JJ/02 installed exipick 20100222.0, added --input-dir and --finput to allow
      exipick to access non-standard spools, including the "frozen" queue
      (Finput)

NM/01 Bugzilla 965: Support mysql stored procedures.
      Patch from Alain Williams

NM/02 Bugzilla 961: Spacing fix (syntax error) on Makefile directives for NetBSD

NM/03 Bugzilla 955: Documentation fix for max_rcpts.
      Patch from Andreas Metzler

NM/04 Bugzilla 954: Fix for unknown responses from Dovecot authenticator.
      Patch from Kirill Miazine

NM/05 Bugzilla 671: Added umask to procmail example.

JJ/03 installed exipick 20100323.0, fixing doc bug

NM/06 Bugzilla 988: CVE-2010-2023 - prevent hardlink attack on sticky mail
      directory.  Notification and patch from Dan Rosenberg.

TK/01 PDKIM: Upgrade PolarSSL files to upstream version 0.12.1.

TK/02 Improve log output when DKIM signing operation fails.

MH/01 Treat the transport option dkim_domain as a colon separated
      list, not as a single string, and sign the message with each element,
      omitting multiple occurences of the same signer.

NM/07 Null terminate DKIM strings, Null initialise DKIM variable
      Bugzilla 985, 986.  Patch by Simon Arlott

NM/08 Bugzilla 967. dnsdb DNS TXT record bug fix (DKIM-related)
      Patch by Simon Arlott

PP/01 Bugzilla 989: CVE-2010-2024 - work round race condition on
      MBX locking.  Notification from Dan Rosenberg.


Exim version 4.71
-----------------

TK/01 Bugzilla 912: Fix DKIM segfault on empty headers/body.

NM/01 Bugzilla 913: Documentation fix for gnutls_* options.

NM/02 Bugzilla 722: Documentation for randint.  Better randomness defaults.

NM/03 Bugzilla 847: Enable DNSDB lookup by default.

NM/04 Bugzilla 915: Flag broken perl installation during build.


Exim version 4.70
-----------------

TK/01 Added patch by Johannes Berg that expands the main option
      "spamd_address" if it starts with a dollar sign.

TK/02 Write list of recipients to X-Envelope-Sender header when building
      the mbox-format spool file for content scanning (suggested by Jakob
      Hirsch).

TK/03 Added patch by Wolfgang Breyha that adds experimental DCC
      (http://www.dcc-servers.net/) support via dccifd. Activated by
      setting EXPERIMENTAL_DCC=yes in Local/Makefile.

TK/04 Bugzilla 673: Add f-protd malware scanner support. Patch submitted
      by Mark Daniel Reidel <mr@df.eu>.

NM/01 Bugzilla 657: Embedded PCRE removed from the exim source tree.
      When building exim an external PCRE library is now needed -
      PCRE is a system library on the majority of modern systems.
      See entry on PCRE_LIBS in EDITME file.

NM/02 Bugzilla 646: Removed unwanted C/R in Dovecot authenticator
      conversation.  Added nologin parameter to request.
      Patch contributed by Kirill Miazine.

TF/01 Do not log submission mode rewrites if they do not change the address.

TF/02 Bugzilla 662: Fix stack corruption before exec() in daemon.c.

NM/03 Bugzilla 602: exicyclog now handles panic log, and creates empty
      log files in place.  Contributed by Roberto Lima.

NM/04 Bugzilla 667: Close socket used by dovecot authenticator.

TF/03 Bugzilla 615: When checking the local_parts router precondition
      after a local_part_suffix or local_part_prefix option, Exim now
      does not use the address's named list lookup cache, since this
      contains cached lookups for the whole local part.

NM/05 Bugzilla 521: Integrated SPF Best Guess support contributed by
      Robert Millan.  Documentation is in experimental-spec.txt.

TF/04 Bugzilla 668: Fix parallel build (make -j).

NM/05.2 Bugzilla 437: Prevent Maildir aux files being created with mode 000.

NM/05.3 Bugzilla 598: Improvement to Dovecot authenticator handling.
      Patch provided by Jan Srzednicki.

TF/05 Leading white space used to be stripped from $spam_report which
      wrecked the formatting. Now it is preserved.

TF/06 Save $spam_score, $spam_bar, and $spam_report in spool files, so
      that they are available at delivery time.

TF/07 Fix the way ${extract is skipped in the untaken branch of a conditional.

TF/08 TLS error reporting now respects the incoming_interface and
      incoming_port log selectors.

TF/09 Produce a more useful error message if an SMTP transport's hosts
      setting expands to an empty string.

NM/06 Bugzilla 744: EXPN did not work under TLS.
      Patch provided by Phil Pennock.

NM/07 Bugzilla 769: Extraneous comma in usage fprintf
      Patch provided by Richard Godbee.

NM/08 Fixed erroneous documentation references to smtp_notquit_acl to be
      acl_smtp_notquit, added index entry.

NM/09 Bugzilla 787: Potential buffer overflow in string_format.
      Patch provided by Eugene Bujak.

NM/10 Bugzilla 770: Problem on some platforms modifying the len parameter to
      accept(). Patch provided by Maxim Dounin.

NM/11 Bugzilla 749: Preserve old behaviour of blanks comparing equal to zero.
      Patch provided by Phil Pennock.

NM/12 Bugzilla 497: Correct behaviour of exiwhat when no config exists.

NM/13 Bugzilla 590: Correct handling of Resent-Date headers.
      Patch provided by Brad "anomie" Jorsch.

NM/14 Bugzilla 622: Added timeout setting to transport filter.
      Patch provided by Dean Brooks.

TK/05 Add native DKIM support (does not depend on external libraries).

NM/15 Bugzilla 854: Removed code that symlinks to pcre as its no longer useful.
      Patch provided by Graeme Fowler.

NM/16 Bugzilla 851: Documentation example syntax fix.

NM/17 Changed NOTICE file to remove references to embedded PCRE.

NM/18 Bugzilla 894: Fix issue with very long lines including comments in
      lsearch.

NM/19 Bugzilla 745: TLS version reporting.
      Patch provided by Phil Pennock.

NM/20 Bugzilla 167: bool: condition support.
      Patch provided by Phil Pennock.

NM/21 Bugzilla 665: gnutls_compat_mode to allow compatibility with broken
      clients. Patch provided by Phil Pennock.

NM/22 Bugzilla 607: prepend (not append) Resent-Message-ID and Resent-Date.
      Patch provided by Brad "anomie" Jorsch.

NM/23 Bugzilla 687: Fix misparses in eximstats.
      Patch provided by Heiko Schlittermann.

NM/24 Bugzilla 688: Fix exiwhat to handle log_selector = +pid.
      Patch provided by Heiko Schlittermann.

NM/25 Bugzilla 727: Use transport mode as default mode for maildirsize file.
      plus update to original patch.

NM/26 Bugzilla 799: Documentation correction for ratelimit.

NM/27 Bugzilla 802: Improvements to local interface IP addr detection.
      Patch provided by David Brownlee.

NM/28 Bugzilla 807: Improvements to LMTP delivery logging.

NM/29 Bugzilla 862, 866, 875: Documentation bugfixes.

NM/30 Bugzilla 888: TLS documentation bugfixes.

NM/31 Bugzilla 896: Dovecot buffer overrun fix.

NM/32 Bugzilla 889: Change all instances of "expr" in shell scripts to "expr --"
      Unlike the original bugzilla I have changed all shell scripts in src tree.

NM/33 Bugzilla 898: Transport filter timeout fix.
      Patch by Todd Rinaldo.

NM/34 Bugzilla 901: Fix sign/unsigned and UTF mismatches.
      Patch by Serge Demonchaux.

NM/35 Bugzilla 39: Base64 decode bug fixes.
      Patch by Jakob Hirsch.

NM/36 Bugzilla 909: Correct connect() call in dcc code.

NM/37 Bugzilla 910: Correct issue with relaxed/simple handling.

NM/38 Bugzilla 908: Removed NetBSD3 support as no longer needed.

NM/39 Bugzilla 911: Fixed MakeLinks build script.


Exim version 4.69
-----------------

TK/01 Add preliminary DKIM support. Currently requires a forked version of
      ALT-N's libdkim that I have put here:
      http://duncanthrax.net/exim-experimental/

      Note to Michael Haardt: I had to rename some vars in sieve.c. They
      were called 'true' and it seems that C99 defines that as a reserved
      keyword to be used with 'bool' variable types. That means you could
      not include C99-style headers which use bools without triggering
      build errors in sieve.c.

NM/01 Bugzilla 592: --help option is handled incorrectly if exim is invoked
      as mailq or other aliases.  Changed the --help handling significantly
      to do whats expected.  exim_usage() emits usage/help information.

SC/01 Added the -bylocaldomain option to eximstats.

NM/02 Bugzilla 619: Defended against bad data coming back from gethostbyaddr.

NM/03 Bugzilla 613: Documentation fix for acl_not_smtp.

NM/04 Bugzilla 628: PCRE update to 7.4 (work done by John Hall).


Exim version 4.68
-----------------

PH/01 Another patch from the Sieve maintainer.

PH/02 When an IPv6 address is converted to a string for single-key lookup
      in an address list (e.g. for an item such as "net24-dbm;/net/works"),
      dots are used instead of colons so that keys in lsearch files need not
      contain colons. This was done some time before quoting was made available
      in lsearch files. However, iplsearch files do require colons in IPv6 keys
      (notated using the quote facility) so as to distinguish them from IPv4
      keys. This meant that lookups for IP addresses in host lists did not work
      for iplsearch lookups.

      This has been fixed by arranging for IPv6 addresses to be expressed with
      colons if the lookup type is iplsearch. This is not incompatible, because
      previously such lookups could never work.

      The situation is now rather anomalous, since one *can* have colons in
      ordinary lsearch keys. However, making the change in all cases is
      incompatible and would probably break a number of configurations.

TK/01 Change PRVS address formatting scheme to reflect latests BATV draft
      version.

MH/01 The "spam" ACL condition code contained a sscanf() call with a %s
      conversion specification without a maximum field width, thereby enabling
      a rogue spamd server to cause a buffer overflow. While nobody in their
      right mind would setup Exim to query an untrusted spamd server, an
      attacker that gains access to a server running spamd could potentially
      exploit this vulnerability to run arbitrary code as the Exim user.

TK/02 Bugzilla 502: Apply patch to make the SPF-Received: header use
      $primary_hostname instead of what libspf2 thinks the hosts name is.

MH/02 The dsearch lookup now uses lstat(2) instead of stat(2) to look for
      a directory entry by the name of the lookup key. Previously, if a
      symlink pointed to a non-existing file or a file in a directory that
      Exim lacked permissions to read, a lookup for a key matching that
      symlink would fail. Now it is enough that a matching directory entry
      exists, symlink or not. (Bugzilla 503.)

PH/03 The body_linecount and body_zerocount variables are now exported in the
      local_scan API.

PH/04 Added the $dnslist_matched variable.

PH/05 Unset $tls_cipher and $tls_peerdn before making a connection as a client.
      This means they are set thereafter only if the connection becomes
      encrypted.

PH/06 Added the client_condition to authenticators so that some can be skipped
      by clients under certain conditions.

PH/07 The error message for a badly-placed control=no_multiline_responses left
      "_responses" off the end of the name.

PH/08 Added -Mvc to output a copy of a message in RFC 2822 format.

PH/09 Tidied the code for creating ratelimiting keys, creating them explicitly
      (without spaces) instead of just copying the configuration text.

PH/10 Added the /noupdate option to the ratelimit ACL condition.

PH/11 Added $max_received_linelength.

PH/12 Added +ignore_defer and +include_defer to host lists.

PH/13 Installed PCRE version 7.2. This needed some changes because of the new
      way in which PCRE > 7.0 is built.

PH/14 Implemented queue_only_load_latch.

PH/15 Removed an incorrect (int) cast when reading the value of SIZE in a
      MAIL command. The effect was to mangle the value on 64-bit systems.

PH/16 Another patch from the Sieve maintainer.

PH/17 Added the NOTQUIT ACL, based on a patch from Ted Cooper.

PH/18 If a system quota error occurred while trying to create the file for
      a maildir delivery, the message "Mailbox is full" was not appended to the
      bounce if the delivery eventually timed out. Change 4.67/27 below applied
      only to a quota excession during the actual writing of the file.

PH/19 It seems that peer DN values may contain newlines (and other non-printing
      characters?) which causes problems in log lines. The DN values are now
      passed through string_printing() before being added to log lines.

PH/20 Added the "servers=" facility to MySQL and PostgreSQL lookups. (Oracle
      and InterBase are left for another time.)

PH/21 Added message_body_newlines option.

PH/22 Guard against possible overflow in moan_check_errorcopy().

PH/23 POSIX allows open() to be a macro; guard against that.

PH/24 If the recipient of an error message contained an @ in the local part
      (suitably quoted, of course), incorrect values were put in $domain and
      $local_part during the evaluation of errors_copy.


Exim version 4.67
-----------------

MH/01 Fix for bug #448, segfault in Dovecot authenticator when interface_address
      is unset (happens when testing with -bh and -oMi isn't used). Thanks to
      Jan Srzednicki.

PH/01 Added a new log selector smtp_no_mail, to log SMTP sessions that do not
      issue a MAIL command.

PH/02 In an ACL statement such as

        deny dnslists = X!=127.0.0.2 : X=127.0.0.2

      if a client was not listed at all, or was listed with a value other than
      127.0.0.2, in the X list, but was listed with 127.0.0.2 in the Y list,
      the condition was not true (as it should be), so access was not denied.
      The bug was that the ! inversion was incorrectly passed on to the second
      item. This has been fixed.

PH/03 Added additional dnslists conditions == and =& which are different from
      = and & when the dns lookup returns more than one IP address.

PH/04 Added gnutls_require_{kx,mac,protocols} to give more control over the
      cipher suites used by GnuTLS. These options are ignored by OpenSSL.

PH/05 After discussion on the list, added a compile time option ENABLE_DISABLE_
      FSYNC, which compiles an option called disable_fsync that allows for
      bypassing fsync(). The documentation is heavily laced with warnings.

SC/01 Updated eximstats to collate all SpamAssassin rejects into one bucket.

PH/06 Some tidies to the infrastructure of the Test Suite that is concerned
      with the auxiliary C programs that it uses: (1) Arrange for BIND_8_COMPAT
      to be defined when compiling on OSX (Darwin); (2) Tidies to the Makefile,
      including adding "make clean"; (3) Added -fPIC when compiling the test
      dynamically loaded module, to get rid of a warning.

MH/02 Fix for bug #451, causing paniclog entries to be written if a bounce
      message fails, move_frozen_messages = true and ignore_bounce_errors_after
      = 0s. The bug is otherwise harmless.

PH/07 There was a bug in the dovecot authenticator such that the value of
      $auth1 could be overwritten, and so not correctly preserved, after a
      successful authentication. This usually meant that the value preserved by
      the server_setid option was incorrect.

PH/08 Added $smtp_count_at_connection_start, deliberately with a long name.

PH/09 Installed PCRE release 7.0.

PH/10 The acl_not_smtp_start ACL was, contrary to the documentation, not being
      run for batched SMTP input. It is now run at the start of every message
      in the batch. While fixing this I discovered that the process information
      (output by running exiwhat) was not always getting set for -bs and -bS
      input. This is fixed, and it now also says "batched" for BSMTP.

PH/11 Added control=no_pipelining.

PH/12 Added $sending_ip_address and $sending_port (mostly Magnus Holmgren's
      patch, slightly modified), and move the expansion of helo_data till after
      the connection is made in the smtp transport (so it can use these
      values).

PH/13 Added ${rfc2047d: to decoded RFC 2047 strings.

PH/14 Added log_selector = +pid.

PH/15 Flush SMTP output before delaying, unless control=no_delay_flush is set.

PH/16 Add ${if forany and ${if forall.

PH/17 Added dsn_from option to vary the From: line in DSNs.

PH/18 Flush SMTP output before performing a callout, unless control =
      no_callout_flush is set.

PH/19 Change 4.64/PH/36 introduced a bug: when address_retry_include_sender
      was true (the default) a successful delivery failed to delete the retry
      item, thus causing premature timeout of the address. The bug is now
      fixed.

PH/20 Added hosts_avoid_pipelining to the smtp transport.

PH/21 Long custom messages for fakedefer and fakereject are now split up
      into multiline responses in the same way that messages for "deny" and
      other ACL rejections are.

PH/22 Applied Jori Hamalainen's speed-up changes and typo fixes to exigrep,
      with slight modification.

PH/23 Applied sieve patches from the maintainer "tracking the latest notify
      draft, changing the syntax and factoring some duplicate code".

PH/24 When the log selector "outgoing_port" was set, the port was shown as -1
      for deliveries of the second and subsequent messages over the same SMTP
      connection.

PH/25 Applied Magnus Holmgren's patch for ${addresses, ${map, ${filter, and
      ${reduce, with only minor "tidies".

SC/02 Applied Daniel Tiefnig's patch to improve the '($parent) =' pattern match.

PH/26 Added a "continue" ACL modifier that does nothing, for the benefit of its
      expansion side effects.

PH/27 When a message times out after an over-quota error from an Exim-imposed
      quota, the bounce message says "mailbox is full". This message was not
      being given when it was a system quota that was exceeded. It now should
      be the same.

MH/03 Made $recipients available in local_scan(). local_scan() already has
      better access to the recipient list through recipients_list[], but
      $recipients can be useful in postmaster-provided expansion strings.

PH/28 The $smtp_command and $smtp_command_argument variables were not correct
      in the case of a MAIL command with additional options following the
      address, for example: MAIL FROM:<foo@bar> SIZE=1234. The option settings
      were accidentally chopped off.

PH/29 SMTP synchronization checks are implemented when a command is read -
      there is a check that no more input is waiting when there shouldn't be
      any. However, for some commands, a delay in an ACL can mean that it is
      some time before the response is written. In this time, more input might
      arrive, invalidly. So now there are extra checks after an ACL has run for
      HELO/EHLO and after the predata ACL, and likewise for MAIL and RCPT when
      pipelining has not been advertised.

PH/30 MH's patch to allow iscntrl() characters to be list separators.

PH/31 Unlike :fail:, a custom message specified with :defer: was not being
      returned in the SMTP response when smtp_return_error_details was false.
      This has been fixed.

PH/32 Change the Dovecot authenticator to use read() and write() on the socket
      instead of the C I/O that was originally supplied, because problems were
      reported on Solaris.

PH/33 Compile failed with OpenSSL 0.9.8e. This was due to a coding error in
      Exim which did not show up earlier: it was assuming that a call to
      SSL_CTX_set_info_callback() might give an error value. In fact, there is
      no error. In previous releases of OpenSSL, SSL_CTX_set_info_callback()
      was a macro that became an assignment, so it seemed to work. This has
      changed to a proper function call with a void return, hence the compile
      error. Exim's code has been fixed.

PH/34 Change HDA_SIZE in oracle.c from 256 to 512. This is needed for 64-bit
      cpus.

PH/35 Applied a patch from the Sieve maintainer which fixes a bug in "notify".

PH/36 Applied John Jetmore's patch to add -v functionality to exigrep.

PH/37 If a message is not accepted after it has had an id assigned (e.g.
      because it turns out to be too big or there is a timeout) there is no
      "Completed" line in the log. When some messages of this type were
      selected by exigrep, they were listed as "not completed". Others were
      picked up by some special patterns. I have improved the selection
      criteria to be more general.

PH/38 The host_find_failed option in the manualroute router can now be set
      to "ignore", to completely ignore a host whose IP address cannot be
      found. If all hosts are ignored, the behaviour is controlled by the new
      host_all_ignored option.

PH/39 In a list of hosts for manualroute, if one item (either because of multi-
      homing or because of multiple MX records with /mx) generated more than
      one IP address, and the following item turned out to be the local host,
      all the secondary addresses of the first item were incorrectly removed
      from the list, along with the local host and any following hosts (which
      is what is supposed to happen).

PH/40 When Exim receives a message, it writes the login name, uid, and gid of
      whoever called Exim into the -H file. In the case of the daemon it was
      behaving confusingly. When first started, it used values for whoever
      started the daemon, but after a SIGHUP it used the Exim user (because it
      calls itself on a restart). I have changed the code so that it now always
      uses the Exim user.

PH/41 (Following a suggestion from Tony Finch) If all the RCPT commands in a
      message are rejected with the same error (e.g. no authentication or bad
      sender address), and a DATA command is nevertheless sent (as can happen
      with PIPELINING or a stupid MUA), the error message that was given to the
      RCPT commands is included in the rejection of the DATA command. This is
      intended to be helpful for MUAs that show only the final error to their
      users.

PH/42 Another patch from the Sieve maintainer.

SC/02 Eximstats - Differentiate between permanent and temporary rejects.
      Eximstats - Fixed some broken HTML links and added missing column headers
                  (Jez Hancock).
      Eximstats - Fixed Grand Total Summary Domains, Edomains, and Email
                  columns for Rejects, Temp Rejects, Ham, and Spam rows.

SC/03 Eximstats - V1.58 Fix to get <> and blackhole to show in edomain tables.

PH/43 Yet another patch from the Sieve maintainer.

PH/44 I found a way to check for a TCP/IP connection going away before sending
      the response to the final '.' that terminates a message, but only in the
      case where the client has not sent further data following the '.'
      (unfortunately, this is allowed). However, in many cases there won't be
      any further data because there won't be any more messages to send. A call
      to select() can be used: if it shows that the input is "ready", there is
      either input waiting, or the socket has been closed. An attempt to read
      the next input character can distinguish the two cases. Previously, Exim
      would have sent an OK response which the client would never have see.
      This could lead to message repetition. This fix should cure that, at
      least in a lot of common cases.

PH/45 Do not advertise STARTTLS in response to HELP unless it would be
      advertised in response to EHLO.


Exim version 4.66
-----------------

PH/01 Two more bugs that were introduced by 4.64/PH/07, in addition to the one
      fixed by 4.65/MH/01 (is this a record?) are fixed:

      (i)  An empty string was always treated as zero by the numeric comparison
           operators. This behaviour has been restored.

      (ii) It is documented that the numeric comparison operators always treat
           their arguments as decimal numbers. This was broken in that numbers
           starting with 0 were being interpreted as octal.

      While fixing these problems I realized that there was another issue that
      hadn't been noticed. Values of message_size_limit (both the global option
      and the transport option) were treated as octal if they started with 0.
      The documentation was vague. These values are now always treated as
      decimal, and I will make that clear in the documentation.


Exim version 4.65
-----------------

TK/01 Disable default definition of HAVE_LINUX_SENDFILE. Clashes with
      Linux large file support (_FILE_OFFSET_BITS=64) on older glibc
      versions. (#438)

MH/01 Don't check that the operands of numeric comparison operators are
      integers when their expansion is in "skipping" mode (fixes bug
      introduced by 4.64-PH/07).

PH/01 If a system filter or a router generates more than SHRT_MAX (32767)
      child addresses, Exim now panics and dies. Previously, because the count
      is held in a short int, deliveries were likely to be lost. As such a
      large number of recipients for a single message is ridiculous
      (performance will be very, very poor), I have chosen to impose a limit
      rather than extend the field.


Exim version 4.64
-----------------

TK/01 Bugzilla #401. Fix DK spooling code so that it can overwrite a
      leftover -K file (the existence of which was triggered by #402).
      While we were at it, introduced process PID as part of the -K
      filename. This should rule out race conditions when creating
      these files.

TK/02 Bugzilla #402. Apply patch from Simon Arlott, speeding up DK signing
      processing considerably. Previous code took too long for large mails,
      triggering a timeout which in turn triggers #401.

TK/03 Introduced HAVE_LINUX_SENDFILE to os.h-Linux. Currently only used
      in the DK code in transports.c. sendfile() is not really portable,
      hence the _LINUX specificness.

TF/01 In the add_headers option to the mail command in an Exim filter,
      there was a bug that Exim would claim a syntax error in any
      header after the first one which had an odd number of characters
      in the field name.

PH/01 If a server that rejects MAIL FROM:<> was the target of a sender
      callout verification, Exim cached a "reject" for the entire domain. This
      is correct for most verifications, but it is not correct for a recipient
      verification with use_sender or use_postmaster set, because in that case
      the callout does not use MAIL FROM:<>. Exim now distinguishes the special
      case of MAIL FROM:<> rejection from other early rejections (e.g.
      rejection of HELO). When verifying a recipient using a non-null MAIL
      address, the cache is ignored if it shows MAIL FROM:<> rejection.
      Whatever the result of the callout, the value of the domain cache is
      left unchanged (for any other kind of callout, getting as far as trying
      RCPT means that the domain itself is ok).

PH/02 Tidied a number of unused variable and signed/unsigned warnings that
      gcc 4.1.1 threw up.

PH/03 On Solaris, an unexpectedly close socket (dropped connection) can
      manifest itself as EPIPE rather than ECONNECT. When tidying away a
      session, the daemon ignores ECONNECT errors and logs others; it now
      ignores EPIPE as well.

PH/04 Applied Nico Erfurth's refactoring patch to tidy up mime.c
      (quoted-printable decoding).

PH/05 Applied Nico Erfurth's refactoring patch to tidy up spool_mbox.c, and
      later the small subsequent patch to fix an introduced bug.

PH/06 Installed the latest Cygwin Makefile from the Cygwin maintainer.

PH/07 There was no check for overflow in expansions such as ${if >{1}{4096M}}.

PH/08 An error is now given if message_size_limit is specified negative.

PH/09 Applied and tidied up Jakob Hirsch's patch for allowing ACL variables
      to be given (somewhat) arbitrary names.

JJ/01 exipick 20060919.0, allow for arbitrary acl_ variables introduced
      in 4.64-PH/09.

JJ/02 exipick 20060919.0, --show-vars args can now be regular expressions,
      miscellaneous code fixes

PH/10 Added the log_reject_target ACL modifier to specify where to log
      rejections.

PH/11 Callouts were setting the name used for EHLO/HELO from $smtp_active_
      hostname. This is wrong, because it relates to the incoming message (and
      probably the interface on which it is arriving) and not to the outgoing
      callout (which could be using a different interface). This has been
      changed to use the value of the helo_data option from the smtp transport
      instead - this is what is used when a message is actually being sent. If
      there is no remote transport (possible with a router that sets up host
      addresses), $smtp_active_hostname is used.

PH/12 Installed Andrey Panin's patch to add a dovecot authenticator. Various
      tweaks were necessary in order to get it to work (see also 21 below):
      (a) The code assumed that strncpy() returns a negative number on buffer
          overflow, which isn't the case. Replaced with Exim's string_format()
          function.
      (b) There were several signed/unsigned issues. I just did the minimum
          hacking in of casts. There is scope for a larger refactoring.
      (c) The code used strcasecmp() which is not a standard C function.
          Replaced with Exim's strcmpic() function.
      (d) The code set only $1; it now sets $auth1 as well.
      (e) A simple test gave the error "authentication client didn't specify
          service in request". It would seem that Dovecot has changed its
          interface. Fortunately there's a specification; I followed it and
          changed what the client sends and it appears to be working now.

PH/13 Added $message_headers_raw to provide the headers without RFC 2047
      decoding.

PH/14 Corrected misleading output from -bv when -v was also used. Suppose the
      address A is aliased to B and C, where B exists and C does not. Without
      -v the output is "A verified" because verification stops after a
      successful redirection if more than one address is generated. However,
      with -v the child addresses are also verified. Exim was outputting "A
      failed to verify" and then showing the successful verification for C,
      with its parentage. It now outputs "B failed to verify", showing B's
      parentage before showing the successful verification of C.

PH/15 Applied Michael Deutschmann's patch to allow DNS black list processing to
      look up a TXT record in a specific list after matching in a combined
      list.

PH/16 It seems that the options setting for the resolver (RES_DEFNAMES and
      RES_DNSRCH) can affect the behaviour of gethostbyname() and friends when
      they consult the DNS. I had assumed they would set it the way they
      wanted; and indeed my experiments on Linux seem to show that in some
      cases they do (I could influence IPv6 lookups but not IPv4 lookups).
      To be on the safe side, however, I have now made the interface to
      host_find_byname() similar to host_find_bydns(), with an argument
      containing the DNS resolver options. The host_find_byname() function now
      sets these options at its start, just as host_find_bydns() does. The smtp
      transport options dns_qualify_single and dns_search_parents are passed to
      host_find_byname() when gethostbyname=TRUE in this transport. Other uses
      of host_find_byname() use the default settings of RES_DEFNAMES
      (qualify_single) but not RES_DNSRCH (search_parents).

PH/17 Applied (a modified version of) Nico Erfurth's patch to make
      spool_read_header() do less string testing, by means of a preliminary
      switch on the second character of optional "-foo" lines. (This is
      overdue, caused by the large number of possibilities that now exist.
      Originally there were few.) While I was there, I also converted the
      str(n)cmp tests so they don't re-test the leading "-" and the first
      character, in the hope this might squeeze out yet more improvement.

PH/18 Two problems with "group" syntax in header lines when verifying: (1) The
      flag allowing group syntax was set by the header_syntax check but not
      turned off, possible causing trouble later; (2) The flag was not being
      set at all for the header_verify test, causing "group"-style headers to
      be rejected. I have now set it in this case, and also caused header_
      verify to ignore an empty address taken from a group. While doing this, I
      came across some other cases where the code for allowing group syntax
      while scanning a header line wasn't quite right (mostly, not resetting
      the flag correctly in the right place). These bugs could have caused
      trouble for malformed header lines. I hope it is now all correct.

PH/19 The functions {pwcheck,saslauthd}_verify_password() are always called
      with the "reply" argument non-NULL. The code, however (which originally
      came from elsewhere) had *some* tests for NULL when it wrote to *reply,
      but it didn't always do it. This confused somebody who was copying the
      code for some other use. I have removed all the tests.

PH/20 It was discovered that the GnuTLS code had support for RSA_EXPORT, a
      feature that was used to support insecure browsers during the U.S. crypto
      embargo. It requires special client support, and Exim is probably the
      only MTA that supported it -- and would never use it because real RSA is
      always available. This code has been removed, because it had the bad
      effect of slowing Exim down by computing (never used) parameters for the
      RSA_EXPORT functionality.

PH/21 On the advice of Timo Sirainen, added a check to the dovecot
      authenticator to fail if there's a tab character in the incoming data
      (there should never be unless someone is messing about, as it's supposed
      to be base64-encoded). Also added, on Timo's advice, the "secured" option
      if the connection is using TLS or if the remote IP is the same as the
      local IP, and the "valid-client-cert option" if a client certificate has
      been verified.

PH/22 As suggested by Dennis Davis, added a server_condition option to *all*
      authenticators. This can be used for authorization after authentication
      succeeds. (In the case of plaintext, it servers for both authentication
      and authorization.)

PH/23 Testing for tls_required and lost_connection in a retry rule didn't work
      if any retry times were supplied.

PH/24 Exim crashed if verify=helo was activated during an incoming -bs
      connection, where there is no client IP address to check. In this
      situation, the verify now always succeeds.

PH/25 Applied John Jetmore's -Mset patch.

PH/26 Added -bem to be like -Mset, but loading a message from a file.

PH/27 In a string expansion for a processed (not raw) header when multiple
      headers of the same name were present, leading whitespace was being
      removed from all of them, but trailing whitespace was being removed only
      from the last one. Now trailing whitespace is removed from each header
      before concatenation. Completely empty headers in a concatenation (as
      before) are ignored.

PH/28 Fixed bug in backwards-compatibility feature of PH/09 (thanks to John
      Jetmore). It would have mis-read ACL variables from pre-4.61 spool files.

PH/29 [Removed. This was a change that I later backed out, and forgot to
      correct the ChangeLog entry (that I had efficiently created) before
      committing the later change.]

PH/30 Exim was sometimes attempting to deliver messages that had suffered
      address errors (4xx response to RCPT) over the same connection as other
      messages routed to the same hosts. Such deliveries are always "forced",
      so retry times are not inspected. This resulted in far too many retries
      for the affected addresses. The effect occurred only when there were more
      hosts than the hosts_max_try setting in the smtp transport when it had
      the 4xx errors. Those hosts that it had tried were not added to the list
      of hosts for which the message was waiting, so if all were tried, there
      was no problem. Two fixes have been applied:

      (i)  If there are any address or message errors in an SMTP delivery, none
           of the hosts (tried or untried) are now added to the list of hosts
           for which the message is waiting, so the message should not be a
           candidate for sending over the same connection that was used for a
           successful delivery of some other message. This seems entirely
           reasonable: after all the message is NOT "waiting for some host".
           This is so "obvious" that I'm not sure why it wasn't done
           previously. Hope I haven't missed anything, but it can't do any
           harm, as the worst effect is to miss an optimization.

      (ii) If, despite (i), such a delivery is accidentally attempted, the
           routing retry time is respected, so at least it doesn't keep
           hammering the server.

PH/31 Installed Andrew Findlay's patch to close the writing end of the socket
      in ${readsocket because some servers need this prod.

PH/32 Added some extra debug output when updating a wait-xxx database.

PH/33 The hint "could be header name not terminated by colon", which has been
      given for certain expansion errors for a long time, was not being given
      for the ${if def:h_colon_omitted{...  case.

PH/34 The spec says: "With one important exception, whenever a domain list is
      being scanned, $domain contains the subject domain." There was at least
      one case where this was not true.

PH/35 The error "getsockname() failed: connection reset by peer" was being
      written to the panic log as well as the main log, but it isn't really
      panic-worthy as it just means the connection died rather early on. I have
      removed the panic log writing for the ECONNRESET error when getsockname()
      fails.

PH/36 After a 4xx response to a RCPT error, that address was delayed (in queue
      runs only) independently of the message's sender address. This meant
      that, if the 4xx error was in fact related to the sender, a different
      message to the same recipient with a different sender could confuse
      things. In particular, this can happen when sending to a greylisting
      server, but other circumstances could also provoke similar problems.
      I have changed the default so that the retry time for these errors is now
      based a combination of the sender and recipient addresses. This change
      can be overridden by setting address_retry_include_sender=false in the
      smtp transport.

PH/37 For LMTP over TCP/IP (the smtp transport), error responses from the
      remote server are returned as part of bounce messages. This was not
      happening for LMTP over a pipe (the lmtp transport), but now it is the
      same for both kinds of LMTP.

PH/38 Despite being documented as not happening, Exim was rewriting addresses
      in header lines that were in fact CNAMEs. This is no longer the case.

PH/39 If -R or -S was given with -q<time>, the effect of -R or -S was ignored,
      and queue runs started by the daemon processed all messages. This has
      been fixed so that -R and -S can now usefully be given with -q<time>.

PH/40 Import PCRE release 6.7 (fixes some bugs).

PH/41 Add bitwise logical operations to eval (courtesy Brad Jorsch).

PH/42 Give an error if -q is specified more than once.

PH/43 Renamed the variables $interface_address and $interface_port as
      $received_ip_address and $received_port, to make it clear that these
      values apply to message reception, and not to the outgoing interface when
      a message is delivered. (The old names remain recognized, of course.)

PH/44 There was no timeout on the connect() call when using a Unix domain
      socket in the ${readsocket expansion. There now is.

PH/45 Applied a modified version of Brad Jorsch's patch to allow "message" to
      b