1. New command-line option -bI:sieve will list all supported sieve extensions
of this Exim build on standard output, one per line.
ManageSieve (RFC 5804) providers managing scripts for use by Exim should
query this to establish the correct list to include in the protocol's
SIEVE capability line.
2. If the -n option is combined with the -bP option, then the name of an
emitted option is not output, only the value (if visible to you).
For instance, "exim -n -bP pid_file_path" should just emit a pathname
followed by a newline, and no other text.
3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
has a "tls_dh_min_bits" option, to set the minimum acceptable number of
bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
acceptable for security. (Option accepted but ignored if using OpenSSL).
Defaults to 1024, the old value. May be lowered only to 512, or raised as
far as you like. Raising this may hinder TLS interoperability with other
sites and is not currently recommended. Lowering this will permit you to
establish a TLS session which is not as secure as you might like.
Unless you really know what you are doing, leave it alone.
4. If not built with DISABLE_DNSSEC, Exim now has the main option
dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
to send the DO flag to your recursive resolver. If you have a recursive
resolver, which can set the Authenticated Data (AD) flag in results, Exim
can now detect this. Exim does not perform validation itself, instead
relying upon a trusted path to the resolver.
Current status: work-in-progress; $sender_host_dnssec variable added.
5. DSCP support for outbound connections: on a transport using the smtp driver,
set "dscp = ef", for instance, to cause the connections to have the relevant
DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
Similarly for inbound connections, there is a new control modifier, dscp,
so "warn control = dscp/ef" in the connect ACL, or after authentication.
Supported values depend upon system libraries. "exim -bI:dscp" to list the
ones Exim knows of. You can also set a raw number 0..0x3F.
6. The -G command-line flag is no longer ignored; it is now equivalent to an
ACL setting "control = suppress_local_fixups". The -L command-line flag
is now accepted and forces use of syslog, with the provided tag as the
process name. A few other flags used by Sendmail are now accepted and
ignored.
7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
ACL modifier; works for single-recipient mails which are recieved on and
deliverable via SMTP. Using the connection made for a recipient verify,
if requested before the verify, or a new one made for the purpose while
the inbound connection is still active. The bulk of the mail item is copied
direct from the inbound socket to the outbound (as well as the spool file).
When the source notifies the end of data, the data acceptance by the destination
is negociated before the acceptance is sent to the source. If the destination
does not accept the mail item, for example due to content-scanning, the item
is not accepted from the source and therefore there is no need to generate
a bounce mail. This is of benefit when providing a secondary-MX service.
The downside is that delays are under the control of the ultimate destination
system not your own.
The Recieved-by: header on items delivered by cutthrough is generated
early in reception rather than at the end; this will affect any timestamp
included. The log line showing delivery is recorded before that showing
reception; it uses a new ">>" tag instead of "=>".
To support the feature, verify-callout connections can now use ESMTP and TLS.
The usual smtp transport options are honoured, plus a (new, default everything)
hosts_verify_avoid_tls.
New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
for specific access to the information for each connection. The old names
are present for now but deprecated.
Not yet supported: IGNOREQUOTA, SIZE, PIPELINING.
8. New expansion operators ${listnamed:name} to get the content of a named list
and ${listcount:string} to count the items in a list.
9. New global option "gnutls_allow_auto_pkcs11", defaults false. The GnuTLS
rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
modules. For some situations this is desirable, but we expect admin in
those situations to know they want the feature. More commonly, it means
that GUI user modules get loaded and are broken by the setuid Exim being
unable to access files specified in environment variables and passed
through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
unless this new option is set.
Some older OS's with earlier versions of GnuTLS might not have pkcs11 ability,
so have also added a build option which can be used to build Exim with GnuTLS
but without trying to use any kind of PKCS11 support. Uncomment this in the
Local/Makefile:
AVOID_GNUTLS_PKCS11=yes
10. The "acl = name" condition on an ACL now supports optional arguments.
New expansion item "${acl {name}{arg}...}" and expansion condition
"acl {{name}{arg}...}" are added. In all cases up to nine arguments
can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
Variable $acl_narg contains the number of arguments. If the ACL sets
a "message =" value this becomes the result of the expansion item,
or the value of $value for the expansion condition. If the ACL returns
accept the expansion condition is true; if reject, false. A defer
return results in a forced fail.
11. Routers and transports can now have multiple headers_add and headers_remove
option lines. The concatenated list is used.
12. New ACL modifier "remove_header" can remove headers before message gets
handled by routers/transports.
13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
"aaaa" and "a" lookups is done and the full set of results returned.
14. New expansion variable $headers_added with content from ACL add_header
modifier (but not yet added to messsage).
15. New 8bitmime status logging option for received messages. Log field "M8S".
16. New authenticated_sender logging option, adding to log field "A".
17. New expansion variables $router_name and $transport_name. Useful
particularly for debug_print as -bt commandline option does not
require privilege whereas -d does.
18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
proposed extension to SMTP from Eric Hall.
19. The pipe transport has gained the force_command option, to allow
decorating commands from user .forward pipe aliases with prefix
wrappers, for instance.
20. Callout connections can now AUTH; the same controls as normal delivery
connections apply.
21. Support for DMARC, using opendmarc libs, can be enabled. It adds new
options: dmarc_forensic_sender, dmarc_history_file, and dmarc_tld_file.
It adds new expansion variables $dmarc_ar_header, $dmarc_status,
$dmarc_status_text, and $dmarc_used_domain. It adds a new acl modifier
dmarc_status. It adds new control flags dmarc_disable_verify and
dmarc_enable_forensic.
22. Add expansion variable $authenticated_fail_id, which is the username
provided to the authentication method which failed. It is available
for use in subsequent ACL processing (typically quit or notquit ACLs).
23. New ACL modifer "udpsend" can construct a UDP packet to send to a given
UDP host and port.
24. New ${hexquote:..string..} expansion operator converts non-printable
characters in the string to \xNN form.
25. Experimental TPDA (Transport Post Delivery Action) function added.
Patch provided by Axel Rau.
26. Experimental Redis lookup added. Patch provided by Warren Baker.
9f0cc65797