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 4.98
+-----------------
+
+JH/01 Use fewer forks & execs for sending many messages to a single host.
+ By passing back more info from the transport to the delivery process,
+ we can loop there. A two-phase queue run will benefit, particularly for
+ mailinglist and smarthost cases.
+
+JH/02 Add transaction support for hintsdbs. The providers supported are tdb and
+ sqlite. Transactions are used for the wait-transport and retry DBs.
+ They imply locking internal to the DB. We no longer need a separate
+ lockfile, can keep the DB handle open for extended periods, yet
+ potentially benefit from concurrency on non-conflicting record uses.
+
+JH/03 With dkim_verify_minimal, avoid calling the DKIM ACL after the first
+ good verify.
+
+JH/04 Remove the docs and support scripts dealing with conversion of Exim
+ version 3 installations.
+
+JH/05 Fix hintsdb support for dbmjz when compiled using sqlite3. Previously
+ the backend support assumed keys would be simple C strings, but dbmjz
+ uses keys with embedded NUL bytes. The builtin hintsdb use is unaffected,
+ but installations using dbmjz will need to rebuild those DBs.
+
+JH/06 Bug 1141: When operating a continued-connection transport, verify that
+ the interface option, if specified, evaluates to match the connection.
+ Previously, a queued message for the same host was sent without checking.
+
+JH/07 Bug 3106: Fix coding in SPA authenticator. A macro argument was not
+ properly parenthesized, resulting in a logic error. While the simple
+ fix was provided by Andrew Aitchison, the over-large code block resulting
+ from this macro made me want to replace it with a real function so more
+ extensive rework becamse needed.
+
+JH/08 The output of "exim -bV" now includes lookup types built as dynamic-load
+ modules.
+
+JH/09 Not a change, but worthy of note: There is no test coverage of the
+ heimdall-gssapi authenticator driver. It does build, though with (on at
+ least one platform) library version conflicts with the gsasl auth
+ driver). Confidence in its operation is lacking.
+
+JH/10 Bug 3108: On platforms not providing strchrnul() [OpenBSD] supply a proper
+ prototype (as well as implementaton). Previously, a return type "int"
+ was assumed, resulting in type-conversion bugs when int and pointer had
+ different size. This resulted in crashes while processing DKIM signatures
+ of received messages. Identification and fix from Qualys Security.
+
+JH/11 Lookups built as dynamic-load modules which support a single lookup
+ type are now only loaded if required by the config. Previously all lookup
+ modules present in the modules directory were loaded; this now applies
+ only to those supporting multiple types.
+
+JH/12 Bug 3112: Fix logging of config-file position for "obsolete lookup
+ syntax". Previously, the end of the top-level file was reported.
+
+JH/13 Bug 3120: Fix parsing of DKIM pubkey DNS record. Previously a crafted
+ record could crash the meesage recieve process. Investigation by
+ Maxim Galaganov.
+
+JH/14 Bug 3116: Fix crash in dkim signing. On kernels supporting immutable
+ memory segments, a write was done into one when a constant string was
+ configured for a transport's dkim private key.
+
+JH/15 Disallow tainted metadata in lists.
+ - Change-of-separator prefixes are handled specially when they are
+ explicit text; only the remainder of the list is expanded. A change-of-
+ separator resulting from expansion will not take effect if tainted.
+ - Elements starting with a plus-sign (named-list inclusion,
+ case-interpretation etc) and (hostlist) @[] (et al) are not handled
+ specially and are still operative at this time - but warnings are logged;
+ if any of these are needed in a list with a tainted element (which taints
+ the entire list at string-expansion time) then a named-list can be used
+ for that element.
+ - Exclamation-marks ("!" signifying negation) are not checked for taint
+ at this time.
+
+Exim version 4.98
+-----------------
+
+JH/01 Support list of dkim results in the dkim_status ACL condition, making
+ it more usable in the data ACL.
+
+JH/02 Bug 3040: Handle error on close of the spool data file during reception.
+ Previously This was only logged, on the assumption that errors would be
+ seen for a previous fflush(). However, a fuse filesystem has been
+ reported as showing this an error for the fclose(). The spool is now in
+ an uncertain state, and we have logged and responded acceptance. Change
+ this to respond with a temp-reject, wipe spoolfiles, and log the error
+ detail.
+
+JH/03 Bug 3030: Fix handling of DNS servfail respons for DANE TLSA. When hit
+ during a recipient verify callout, a QUIT command was attempted on the
+ now-closed callout channel, causing a paniclog entry.
+
+JH/04 Bug 3039: Fix handling of of an empty log_reject_target, with
+ a connection_reject log_selector, under tls_on_connect. Previously
+ with this combination, when the connect ACL rejected, a spurious
+ paniclog entry was made.
+
+JH/05 Fix TLS resumption for TLS-on-connect. This was broken by the advent
+ of loadbalancer-detection for resumption, in 4.96 - which tries to
+ use the EHLO response. SMTPS does not have one at the time it is starting
+ TLS. Change the default for the smtp transport host_name_extract option
+ to be a static string, for TLS-on-connect cases; meaning that resumption
+ will always be attempted (unless deliberately overriden).
+
+JH/06 Bug 3054: Fix dnsdb lookup for a TXT record with multiple chunks, with a
+ chunk-separator specification. This was broken by hardening introduced
+ for Bug 3031.
+
+JH/07 Bug 3050: Fix -bp for old message_id format spoolfiles. Previously it
+ included the -H with the id; this also messed up exiqgrep.
+
+JH/08 Bug 3056: Tighten up parsing of DKIM DNS records. Previously, whitespace
+ was not properly skipped and empty elements would cause mis-parsing.
+ Tighten parsing of DKIM header records. Previously, all but lowercase
+ alpha chars would be ignored in potential tag names.
+
+JH/09 Bug 3057: Add heuristic for spotting mistyped IPv6 addresses in lists
+ being searched. Previously we only had one for IPv4 addresses. Per the
+ documentation, the error results by default in a no-match result for the
+ list. It is logged if the unknown_in_list log_selector is used.
+
+JH/10 Bug 3058: Ensure that a failing expansion in a router "set" option defers
+ the routing operation. Previously it would silently stop routing the
+ message.
+
+JH/11 Bug 3046: Fix queue-runs. Previously, the arrivel of a notification or
+ info-request event close in time to a scheduled run timer could result in
+ the latter being missed, and no further queue scheduled runs being
+ initiated. This ouwld be more likely on high-load systems.
+
+JH/12 Refuse to accept a line "dot, LF" as end-of-DATA unless operating in
+ LF-only mode (as detected from the first header line). Previously we did
+ accept that in (normal) CRLF mode; this has been raised as a possible
+ attack scenario (under the name "smtp smuggling").
+
+JH/13 Add an fdatasync call for the received message data file in spool, before
+ loggging reception and sending the SMTP ack. Previously we only flushed
+ the stdio buffer so there was still the possibility of a disk error.
+
+JH/14 Bug 3061: Avoid a split log line when trying to rewrite a malformed
+ address. Previously, for the last address in a header line (commonly
+ there is only one) the terminating newline was part of the logged
+ information.
+
+JH/15 Bug 3061: Ensure a log line is written for a malformed address in a
+ header, when parsing for address-qualification. Previously one was only
+ written if there were rewrite rules.
+
+JH/16 Two-phase queue runs are now reported in the daemon startup log line and
+ in exiwhat output.
+
+JH/17 Bug 3064: Fix combination of "-q<period> -R <recipients>". Introduction of
+ the multiple-queue-runners facility for 4.97 broke this, giving only a
+ one-time run of the queue.
+
+JH/18 Bug 3068: Log a warning for use of deprecated syntax in query-style
+ lookups.
+
+JH/19 Fix TLS startup. When the last expansion done before the initiation of a
+ TLS session resulted in a forced-fail, a misleading error was logged for
+ the expansino of tls_certificates. This would affect the common case of
+ that option being set (main-section options) but not having any variable
+ parts. It could also potentially affect tls_privatekeys. The underlyding
+ coding errors go back to 4.90 but were only exposed in 4.97.
+
+JH/20 Bug 3047: A recent (somewhere between 10.34 and 10.42) version of the
+ pcre2 library starting allocating 20kB rather than 112 bytes per match
+ call, which broke the 2GB total limitation on Exim's memory management
+ when a user had over 104207 messages stored and the appendfile
+ maildir_quota_directory_regex option is in use. Release the allocated
+ memory every thosand files to avoid this.
+ The same issue arises with the ACL regex condition, which is applied
+ to every line of a received message.
+
+JH/21 Bug 3059: Fix crash in smtp transport. When running for a message for
+ which all recipients had been handled (itself an issue) a null-pointer
+ deref was done on trying to write a retry record. Fix that by counting
+ the outstanding recipients before trying to transmit the message.
+ The situation arose for a second MX try within a transport run, when the
+ first had perm-rejected a recipient (the only one for the connection, in
+ the case seen) during pipelining, and then closed the TCP connection.
+ The transport classified that as an I/O error, leaving the message
+ outstanding but having marked up the recipient as dealt-with. It then
+ tried another MX because of the I/O error. Fix this by converting the
+ message-level status to ok if there was a close but all recipients were
+ dealt with. Thanks to Wolfgand Breyha for debug runs.
+
+JH/22 The ESMTP_LIMITS facility (RFC 9422) is promoted from experimental status
+ and is now controlled by the build-time option DISABLE_ESMTP_LIMITS.
+
+JH/23 Bug 3066: Avoid leaking lookup database credentials to log.
+
+JH/24 Bug 3081: Fix a delivery process crash. When the router "errors_to"
+ option specified a fixed address, later rewriting on that address would
+ trip on the configuration data being readonly. Instead of modifying
+ in-place, copy data. Found and fixed by Peter Benie.
+
+JH/25 Bug 3079: Fix crash in dbmnz. When a key was present for zero-length
+ data a null pointer was followed. Find and testcase by Sebastian Bugge.
+
+JH/26 Fix encoding for an AUTH parameter on a MAIL FROM command. Previously
+ decimal 127 chars were not encoded, and lowercase hex was used for
+ encoded values. Outstanding since at least 1999.
+
+JH/27 Fix crash in logging. When a message with a large number of recipients
+ had been received, and logging of recipients is enabled, the buffer used
+ for logging could reach limit. A read using a null pointer would then
+ be done, resulting in a crash of the receiving process before an SMTP
+ ACK for the message was returned to the sending system. Duplicate
+ messages were created as a result.
+ Find and debug help by Mateusz Krawczyk
+
+JH/28 Bug 3086: Fix exinext for ipv6. Change the format of keys in the retry
+ DB, wrapping transport record bare-ip "host names" and ipv6
+ "host addresses" in square-brackets. This makes the parsing that
+ exinext does more reliable.
+
+JH/29 Bug 3087: Fix SRS encode. A zero-length quoted element in the local-part
+ would cause a crash.
+
+JH/30 Bug 3029: Avoid feeding Resent-From: to DMARC.
+
+JH/31 Bug 3027: For -bh / -bhc tests change to using the compressed form of
+ ipv6 addresses for the sender. Previously the uncompressed form was used,
+ and if used in textual form this would result in behavior difference
+ versus non-bh.
+
+JH/32 Bug 3096: MAIL before HELO/EHLO, where required by hosts_require_helo, is
+ now classed as a protocol error and subject to smtp_max_synprot_errors.
+
+JH/33 Bug 2994: A subdir dsearch lookup should permit a directory name that starts
+ ".." and has following characters.
+
+JH/34 Fix delivery ordering for 2-phase queue run combined with
+ queue_run_in_order.
+
+JH/35 Bug 3099: fix parsing of MIME filename= split over multiple paramemters.
+ Previously the $mime_filename variable would have an incorrect value.
+ While in the code, extend coverage to name= which previously was only
+ supported for single parameters, despite also filling in $mime_filename.
+
+
+Exim version 4.97
+-----------------
+
+JH/01 The hosts_connection_nolog main option now also controls "no MAIL in
+ SMTP connection" log lines.
+
+JH/02 Option default value updates:
+ - queue_fast_ramp (main) true (was false)
+ - remote_max_parallel (main) 4 (was 2)
+
+JH/03 Cache static regex pattern compilations, for use by ACLs.
+
+JH/04 Bug 2903: avoid exit on an attempt to rewrite a malformed address.
+ Make the rewrite never match and keep the logging. Trust the
+ admin to be using verify=header-syntax (to actually reject the message).
+
+JH/05 Follow symlinks for placing a watch on TLS creds files. This means
+ (under Linux) we watch the dir containing the final file; previously
+ it would be the dir with the first symlink. We still do not monitor
+ the entire path.
+
+JH/06 Check for bad chars in rDNS for sender_host_name. The OpenBSD (at least)
+ dn_expand() is happy to pass them through.
+
+JH/07 OpenSSL Fix auto-reload of changed server OCSP proof. Previously, if
+ the file with the proof had an unchanged name, the new proof(s) were
+ loaded on top of the old ones (and nover used; the old ones were stapled).
+
+JH/08 Bug 2915: Fix use-after-free for $regex<n> variables. Previously when
+ more than one message arrived in a single connection a reference from
+ the earlier message could be re-used. Often a sigsegv resulted.
+ These variables were introduced in Exim 4.87.
+ Debug help from Graeme Fowler.
+
+JH/09 Fix ${filter } for conditions that modify $value. Previously the
+ modified version would be used in construction the result, and a memory
+ error would occur.
+
+JH/10 GnuTLS: fix for (IOT?) clients offering no TLS extensions at all.
+ Find and fix by Jasen Betts.
+
+JH/11 OpenSSL: fix for ancient clients needing TLS support for versions earlier
+ than TLSv1,2, Previously, more-recent versions of OpenSSL were permitting
+ the systemwide configuration to override the Exim config.
+
+HS/01 Bug 2728: Introduce EDITME option "DMARC_API" to work around incompatible
+ API changes in libopendmarc.
+
+JH/12 Bug 2930: Fix daemon startup. When started from any process apart from
+ pid 1, in the normal "background daemon" mode, having to drop process-
+ group leadership also lost track of needing to create listener sockets.
+
+JH/13 Bug 2929: Fix using $recipients after ${run...}. A change made for 4.96
+ resulted in the variable appearing empty. Find and fix by Ruben Jenster.
+
+JH/14 Bug 2933: Fix regex substring match variables for null matches. Since 4.96
+ a capture group which obtained no text (eg. "(abc)*" matching zero
+ occurrences) could cause a segfault if the corresponding $<n> was
+ expanded.
+
+JH/15 Fix argument parsing for ${run } expansion. Previously, when an argument
+ included a close-brace character (eg. it itself used an expansion) an
+ error occurred.
+
+JH/16 Move running the smtp connect ACL to before, for TLS-on-connect ports,
+ starting TLS. Previously it was after, meaning that attackers on such
+ ports had to be screened using the host_reject_connection main config
+ option. The new sequence aligns better with the STARTTLS behaviour, and
+ permits defences against crypto-processing load attacks, even though it
+ is strictly an incompatible change.
+ Also, avoid sending any SMTP fail response for either the connect ACL
+ or host_reject_connection, for TLS-on-connect ports.
+
+JH/17 Permit the ACL "encrypted" condition to be used in a HELO/EHLO ACL,
+ Previously this was not permitted, but it makes reasonable sense.
+ While there, restore a restriction on using it from a connect ACL; given
+ the change JH/16 it could only return false (and before 4.91 was not
+ permitted).
+
+JH/18 Fix a fencepost error in logging. Previously (since 4.92) when a log line
+ was exactly sized compared to the log buffer, a crash occurred with the
+ misleading message "bad memory reference; pool not found".
+ Found and traced by Jasen Betts.
+
+JH/19 Bug 2911: Fix a recursion in DNS lookups. Previously, if the main option
+ dns_again_means_nonexist included an element causing a DNS lookup which
+ itself returned DNS_AGAIN, unbounded recursion occurred. Possible results
+ included (though probably not limited to) a process crash from stack
+ memory limit, or from excessive open files. Replace this with a paniclog
+ whine (as this is likely a configuration error), and returning
+ DNS_NOMATCH.
+
+JH/20 Bug 2954: (OpenSSL) Fix setting of explicit EC curve/group. Previously
+ this always failed, probably leading to the usual downgrade to in-clear
+ connections.
+
+JH/21 Fix TLSA lookups. Previously dns_again_means_nonexist would affect
+ SERVFAIL results, which breaks the downgrade resistance of DANE. Change
+ to not checking that list for these lookups.
+
+JH/22 Bug 2434: Add connection-elapsed "D=" element to more connection
+ closure log lines.
+
+JH/23 Fix crash in string expansions. Previously, if an empty variable was
+ immediately followed by an expansion operator, a null-indirection read
+ was done, killing the process.
+
+JH/24 Bug 2997: When built with EXPERIMENTAL_DSN_INFO, bounce messages can
+ include an SMTP response string which is longer than that supported
+ by the delivering transport. Alleviate by wrapping such lines before
+ column 80.
+
+JH/25 Bug 2827: Restrict size of References: header in bounce messages to 998
+ chars (RFC limit). Previously a limit of 12 items was made, which with
+ a not-impossible References: in the message being bounced could still
+ be over-large and get stopped in the transport.
+
+JH/26 For a ${readsocket } in TLS mode, send a TLS Close Alert before the TCP
+ close. Previously a bare socket close was done.
+
+JH/27 Fix ${srs_encode ..}. Previously it would give a bad result for one day
+ every 1024 days.
+
+JH/28 Bug 2996: Fix a crash in the smtp transport. When finding that the
+ message being considered for delivery was already being handled by
+ another process, and having an SMTP connection already open, the function
+ to close it tried to use an uninitialized variable. This would afftect
+ high-volume sites more, especially when running mailing-list-style loads.
+ Pollution of logs was the major effect, as the other process delivered
+ the message. Found and partly investigated by Graeme Fowler.
+
+JH/29 Change format of the internal ID used for message identification. The old
+ version only supported 31 bits for a PID element; the new 64 (on systems
+ which can use Base-62 encoding, which is all currently supported ones
+ but not Darwin (MacOS) or Cygwin, which have case-insensitive filesystems
+ and must use Base-36). The new ID is 23 characters rather than 16, and is
+ visible in various places - notably logs, message headers, and spool file
+ names. Various of the ancillary utilities also have to know the format.
+ As well as the expanded PID portion, the sub-second part of the time
+ recorded in the ID is expanded to support finer precision. Theoretically
+ this permits a receive rate from a single comms channel of better than the
+ previous 2000/sec.
+ The major timestamp part of the ID is not changed; at 6 characters it is
+ usable until about year 3700.
+ Updating from previously releases is fully supported: old-format spool
+ files are still usable, and the utilities support both formats. New
+ message will use the new format. The one hints-DB file type which uses
+ message-IDs (the transport wait- DB) will be discarded if an old-format ID
+ is seen; new ones will be built with only new-format IDs.
+ Optionally, a utility can be used to convert spool files from old to new,
+ but this is only an efficiency measure not a requirement for operation
+ Downgrading from new to old requires running a provided utility, having
+ first stopped all operations. This will convert any spool files from new
+ back to old (losing time-precision and PID information) and remove any
+ wait- hints databases.
+
+JH/30 Bug 3006: Fix handling of JSON strings having embedded commas. Previously
+ we treated them as item separators when parsing for a list item, but they
+ need to be protected by the doublequotes. While there, add handling for
+ backslashes.
+
+JH/31 Bug 2998: Fix ${utf8clean:...} to disallow UTF-16 surrogate codepoints.
+ Found and fixed by Jasen Betts. No testcase for this as my usual text
+ editor insists on emitting only valid UTF-8.
+
+JH/32 Fix "tls_dhparam = none" under GnuTLS. At least with 3.7.9 this gave
+ a null-indirection SIGSEGV for the receive process.
+
+JH/33 Fix free for live variable $value created by a ${run ...} expansion during
+ -bh use. Internal checking would spot this and take a panic.
+
+JH/34 Bug 3013: Fix use of $recipients within arguments for ${run...}.
+ In 4.96 this would expand to empty.
+
+JH/35 Bug 3014: GnuTLS: fix expiry date for an auto-generated server
+ certificate. Find and fix by Andreas Metzler.
+
+JH/36 Add ARC info to DMARC hostory records.
+
+JH/37 Bug 3016: Avoid sending DSN when message was accepted under fakereject
+ or fakedefer. Previously the sender could discover that the message
+ had in fact been accepted.
+
+JH/38 Taint-track intermediate values from the peer in multi-stage authentation
+ sequences. Previously the input was not noted as being tainted; notably
+ this resulted in behaviour of LOGIN vs. PLAIN being inconsistent under
+ bad coding of authenticators.
+
+JH/39 Bug 3023: Fix crash induced by some combinations of zero-length strings
+ and ${tr...}. Found and diagnosed by Heiko Schlichting.
+
+JH/40 Bug 2999: Fix a possible OOB write in the external authenticator, which
+ could be triggered by externally-supplied input. Found by Trend Micro.
+ CVE-2023-42115
+
+JH/41 Bug 3000: Fix a possible OOB write in the SPA authenticator, which could
+ be triggered by externally-controlled input. Found by Trend Micro.
+ CVE-2023-42116
+
+JH/42 Bug 3001: Fix a possible OOB read in the SPA authenticator, which could
+ be triggered by externally-controlled input. Found by Trend Micro.
+ CVE-2023-42114
+
+JH/43 Bug 2903: avoid exit on an attempt to rewrite a malformed address.
+ Make the rewrite never match and keep the logging. Trust the
+ admin to be using verify=header-syntax (to actually reject the message).
+
+JH/44 Bug 3033: Harden dnsdb lookups against crafted DNS responses.
+ CVE-2023-42219
+
+HS/02 Fix string_is_ip_address() CVE-2023-42117 (Bug 3031)
+
+
Exim version 4.96
-----------------
-JH/01 Move the wait-for-next-tick (needed for unique messmage IDs) from
+JH/01 Move the wait-for-next-tick (needed for unique message IDs) from
after reception to before a subsequent reception. This should
mean slightly faster delivery, and also confirmation of reception
to senders.
was touched.
JH/16 Debugging initiated by an ACL control now continues through into routing
- and transport processes, when delivery is immediate. Previously debugging
- stopped any time Exim re-execs.
+ and transport processes. Previously debugging stopped any time Exim
+ re-execs, or for processing a queued message.
JH/17 The "expand" debug selector now gives more detail, specifically on the
result of expansion operators and items.
overlapping memcpy for newly allocated destination soon after a
source string shorter than the limit. Found/investigated by KM.
+JH/31 Bug 2886: GnuTLS: Do not free the cached creds on transport connection
+ close; it may be needed for a subsequent connection. This caused a
+ SEGV on primary-MX defer. Found/investigated by Gedalya & Andreas.
+
+JH/32 Fix CHUNKING for a second message on a connection when the first was
+ rejected. Previously we did not reset the chunking-offered state, and
+ erroneously rejected the BDAT command. Investigation help from
+ Jesse Hathaway.
+
+JH/33 Fis ${srs_encode ...} to handle an empty sender address, now returning
+ an empty address. Previously the expansion returned an error.
+
+HS/01 Bug 2855: Handle a v4mapped sender address given us by a frontending
+ proxy. Previously these were misparsed, leading to paniclog entries.
+
Exim version 4.95
-----------------
mx_fail_domains.
JH/45 Use a (new) separate store pool-pair for DKIM verify working data.
- Previously the permanent pool was used, so the sore could not be freed.
+ Previously the permanent pool was used, so the store could not be freed.
This meant a connection with many messages would use continually-growing
memory.
git://git.exim.org / exim.git / blobdiff