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 4.95
+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 Move the wait-for-next-tick (needed for unique messmage IDs) from
+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 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.
the command line may be tainted, in default mode the executable name
may not be tainted.
+JH/26 Fix CHUNKING on a continued-transport. Previously the usabliility of
+ the the facility was not passed across execs, and only the first message
+ passed over a connection could use BDAT; any further ones using DATA.
+
+JH/27 Support the PIPECONNECT facility in the smtp transport when the helo_data
+ uses $sending_ip_address and an interface is specified.
+ Previously any use of the local address in the EHLO name disabled
+ PIPECONNECT, the common case being to use the rDNS of it.
+
+JH/28 OpenSSL: fix transport-required OCSP stapling verification under session
+ resumption. Previously verify failed because no certificate status is
+ passed on the wire for the restarted session. Fix by using the recorded
+ ocsp status of the stored session for the new connection.
+
+JH/29 TLS resumption: the key for session lookup in the client now includes
+ more info that a server could potentially use in configuring a TLS
+ session, avoiding oferring mismatching sessions to such a server.
+ Previously only the server IP was used.
+
+JH/30 Fix string_copyn() for limit greater than actual string length.
+ Previously the copied amount was the limit, which could result in a
+ overlapping memcpy for newly allocated destination soon after a
+ source string shorter than the limit. Found/investigated by KM.
+
+JH/31 Bug 2886: GnuTLS: Do not free the cached creds on transport connection
+ close; it may be needed for a subsequent connection. This caused a
+ SEGV on primary-MX defer. Found/investigated by Gedalya & Andreas.
+
+JH/32 Fix CHUNKING for a second message on a connection when the first was
+ rejected. Previously we did not reset the chunking-offered state, and
+ erroneously rejected the BDAT command. Investigation help from
+ Jesse Hathaway.
+
+JH/33 Fis ${srs_encode ...} to handle an empty sender address, now returning
+ an empty address. Previously the expansion returned an error.
+
+HS/01 Bug 2855: Handle a v4mapped sender address given us by a frontending
+ proxy. Previously these were misparsed, leading to paniclog entries.
+
Exim version 4.95
-----------------
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