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.
b333d0b822