that might affect a running system.
-Exim version 4.78
+Exim version 4.82
-----------------
+ * New option gnutls_allow_auto_pkcs11 defaults false; if you have GnuTLS 2.12.0
+ or later and do want PKCS11 modules to be autoloaded, then set this option.
+
+ * A per-transport wait-<name> database is no longer updated if the transport
+ sets "connection_max_messages" to 1, as it can not be used and causes
+ unnecessary serialisation and load. External tools tracking the state of
+ Exim by the hints databases may need modification to take this into account.
+
+ * The av_scanner option can now accept multiple clamd TCP targets, all other
+ setting limitations remain.
+
+
+Exim version 4.80
+-----------------
+
+ * BEWARE backwards-incompatible changes in SSL libraries, thus the version
+ bump. See points below for details.
+ Also an LDAP data returned format change.
+
* The value of $tls_peerdn is now print-escaped when written to the spool file
in a -tls_peerdn line, and unescaped when read back in. We received reports
of values with embedded newlines, which caused spool file corruption.
the message. No tool has been provided as we believe this is a rare
occurence.
+ * For OpenSSL, SSLv2 is now disabled by default. (GnuTLS does not support
+ SSLv2). RFC 6176 prohibits SSLv2 and some informal surveys suggest no
+ actual usage. You can re-enable with the "openssl_options" Exim option,
+ in the main configuration section. Note that supporting SSLv2 exposes
+ you to ciphersuite downgrade attacks.
+
* With OpenSSL 1.0.1+, Exim now supports TLS 1.1 and TLS 1.2. If built
against 1.0.1a then you will get a warning message and the
"openssl_options" value will not parse "no_tlsv1_1": the value changes
"openssl_options" gains "no_tlsv1_1", "no_tlsv1_2" and "no_compression".
+ COMPATIBILITY WARNING: The default value of "openssl_options" is no longer
+ "+dont_insert_empty_fragments". We default to "+no_sslv2".
+ That old default was grandfathered in from before openssl_options became a
+ configuration option.
+ Empty fragments are inserted by default through TLS1.0, to partially defend
+ against certain attacks; TLS1.1+ change the protocol so that this is not
+ needed. The DIEF SSL option was required for some old releases of mail
+ clients which did not gracefully handle the empty fragments, and was
+ initially set in Exim release 4.31 (see ChangeLog, item 37).
+
+ If you still have affected mail-clients, and you see SSL protocol failures
+ with this release of Exim, set:
+ openssl_options = +dont_insert_empty_fragments
+ in the main section of your Exim configuration file. You're trading off
+ security for compatibility. Exim is now defaulting to higher security and
+ rewarding more modern clients.
+
+ If the option tls_dhparams is set and the parameters loaded from the file
+ have a bit-count greater than the new option tls_dh_max_bits, then the file
+ will now be ignored. If this affects you, raise the tls_dh_max_bits limit.
+ We suspect that most folks are using dated defaults and will not be affected.
+
* Ldap lookups returning multi-valued attributes now separate the attributes
with only a comma, not a comma-space sequence. Also, an actual comma within
a returned attribute is doubled. This makes it possible to parse the
attribute as a comma-separated list. Note the distinction from multiple
attributes being returned, where each one is a name=value pair.
+ If you are currently splitting the results from LDAP upon a comma, then you
+ should check carefully to see if adjustments are needed.
+
+ This change lets cautious folks distinguish "comma used as separator for
+ joining values" from "comma inside the data".
+
+ * accept_8bitmime now defaults on, which is not RFC compliant but is better
+ suited to today's Internet. See http://cr.yp.to/smtp/8bitmime.html for a
+ sane rationale. Those who wish to be strictly RFC compliant, or know that
+ they need to talk to servers that are not 8-bit-clean, now need to take
+ explicit configuration action to default this option off. This is not a
+ new option, you can safely force it off before upgrading, to decouple
+ configuration changes from the binary upgrade while remaining RFC compliant.
+
+ * The GnuTLS support has been mostly rewritten, to use APIs which don't cause
+ deprecation warnings in GnuTLS 2.12.x. As part of this, these three options
+ are no longer supported:
+
+ gnutls_require_kx
+ gnutls_require_mac
+ gnutls_require_protocols
+
+ Their functionality is entirely subsumed into tls_require_ciphers. In turn,
+ tls_require_ciphers is no longer an Exim list and is not parsed by Exim, but
+ is instead given to gnutls_priority_init(3), which expects a priority string;
+ this behaviour is much closer to the OpenSSL behaviour. See:
+
+ http://www.gnutls.org/manual/html_node/Priority-Strings.html
+
+ for fuller documentation of the strings parsed. The three gnutls_require_*
+ options are still parsed by Exim and, for this release, silently ignored.
+ A future release will add warnings, before a later still release removes
+ parsing entirely and the presence of the options will be a configuration
+ error.
+
+ Note that by default, GnuTLS will not accept RSA-MD5 signatures in chains.
+ A tls_require_ciphers value of NORMAL:%VERIFY_ALLOW_SIGN_RSA_MD5 may
+ re-enable support, but this is not supported by the Exim maintainers.
+ Our test suite no longer includes MD5-based certificates.
+
+ This rewrite means that Exim will continue to build against GnuTLS in the
+ future, brings Exim closer to other GnuTLS applications and lets us add
+ support for SNI and other features more readily. We regret that it wasn't
+ feasible to retain the three dropped options.
+
+ * If built with TLS support, then Exim will now validate the value of
+ the main section tls_require_ciphers option at start-up. Before, this
+ would cause a STARTTLS 4xx failure, now it causes a failure to start.
+ Running with a broken configuration which causes failures that may only
+ be left in the logs has been traded off for something more visible. This
+ change makes an existing problem more prominent, but we do not believe
+ anyone would deliberately be running with an invalid tls_require_ciphers
+ option.
+
+ This also means that library linkage issues caused by conflicts of some
+ kind might take out the main daemon, not just the delivery or receiving
+ process. Conceivably some folks might prefer to continue delivering
+ mail plaintext when their binary is broken in this way, if there is a
+ server that is a candidate to receive such mails that does not advertise
+ STARTTLS. Note that Exim is typically a setuid root binary and given
+ broken linkage problems that cause segfaults, we feel it is safer to
+ fail completely. (The check is not done as root, to ensure that problems
+ here are not made worse by the check).
+
+ * The "tls_dhparam" option has been updated, so that it can now specify a
+ path or an identifier for a standard DH prime from one of a few RFCs.
+ The default for OpenSSL is no longer to not use DH but instead to use
+ one of these standard primes. The default for GnuTLS is no longer to use
+ a file in the spool directory, but to use that same standard prime.
+ The option is now used by GnuTLS too. If it points to a path, then
+ GnuTLS will use that path, instead of a file in the spool directory;
+ GnuTLS will attempt to create it if it does not exist.
+
+ To preserve the previous behaviour of generating files in the spool
+ directory, set "tls_dhparam = historic". Since prior releases of Exim
+ ignored tls_dhparam when using GnuTLS, this can safely be done before
+ the upgrade.
+
+
Exim version 4.77
-----------------
problem. Prior to this release, supported values were "TLS1" and "SSL3",
so you should be able to update configuration prior to update.
+ [nb: gnutls_require_protocols removed in Exim 4.80, instead use
+ tls_require_ciphers to provide a priority string; see notes above]
+
* The match_<type>{string1}{string2} expansion conditions no longer subject
string2 to string expansion, unless Exim was built with the new
"EXPAND_LISTMATCH_RHS" option. Too many people have inadvertently created
git://git.exim.org / users / jgh / exim.git / blobdiff