X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/a5bd321b2f16ff323e3e268d59606e89b747a901..e9eb345703f60f91a25b474ad3f85ebee5193e9e:/src/README.UPDATING?ds=inline diff --git a/src/README.UPDATING b/src/README.UPDATING index e4975ba6a..3ee3035e9 100644 --- a/src/README.UPDATING +++ b/src/README.UPDATING @@ -1,5 +1,3 @@ -$Cambridge: exim/src/README.UPDATING,v 1.12 2006/07/13 13:53:33 ph10 Exp $ - This document contains detailed information about incompatibilities that might be encountered when upgrading from one release of Exim to another. The information is in reverse order of release numbers. Mostly these are relatively @@ -28,6 +26,143 @@ The rest of this document contains information about changes in 4.xx releases that might affect a running system. +Exim version 4.77 +----------------- + + * GnuTLS will now attempt to use TLS 1.2 and TLS 1.1 before TLS 1.0 and SSL3, + if supported by your GnuTLS library. Use the existing + "gnutls_require_protocols" option to downgrade this if that will be a + problem. Prior to this release, supported values were "TLS1" and "SSL3", + so you should be able to update configuration prior to update. + + * The match_{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 + insecure configurations that way. If you need the functionality and turn on + that build option, please let the developers know, and know why, so we can + try to provide a safer mechanism for you. + + The match{}{} expansion condition (for regular expressions) is NOT affected. + For match_{s1}{s2}, all list functionality is unchanged. The only + change is that a '$' appearing in s2 will not trigger expansion, but instead + will be treated as a literal $ sign; the effect is very similar to having + wrapped s2 with \N...\N. If s2 contains a named list and the list definition + uses $expansions then those _will_ be processed as normal. It is only the + point at which s2 is read where expansion is inhibited. + + If you are trying to test if two email addresses are equal, use eqi{s1}{s2}. + If you are testing if the address in s1 occurs in the list of items given + in s2, either use the new inlisti{s1}{s2} condition (added in 4.77) or use + the pre-existing forany{s2}{eqi{$item}{s1}} condition. + + +Exim version 4.74 +----------------- + + * The integrated support for dynamically loadable lookup modules has an ABI + change from the modules supported by some OS vendors through an unofficial + patch. Don't try to mix & match. + + * Some parts of the build system are now beginning to assume that the host + environment is POSIX. If you're building on a system where POSIX tools are + not the default, you might have an easier time if you switch to the POSIX + tools. Feel free to report non-POSIX issues as a request for a feature + enhancement, but if the POSIX variants are available then the fix will + probably just involve some coercion. See the README instructions for + building on such hosts. + + +Exim version 4.73 +----------------- + + * The Exim run-time user can no longer be root; this was always + strongly discouraged, but is now prohibited both at build and + run-time. If you need Exim to run routinely as root, you'll need to + patch the source and accept the risk. Here be dragons. + + * Exim will no longer accept a configuration file owned by the Exim + run-time user, unless that account is explicitly the value in + CONFIGURE_OWNER, which we discourage. Exim now checks to ensure that + files are not writeable by other accounts. + + * The ALT_CONFIG_ROOT_ONLY build option is no longer optional and is forced + on; the Exim user can, by default, no longer use -C/-D and retain privilege. + Two new build options mitigate this. + + * TRUSTED_CONFIG_LIST defines a file containing a whitelist of config + files that are trusted to be selected by the Exim user; one per line. + This is the recommended approach going forward. + + * WHITELIST_D_MACROS defines a colon-separated list of macro names which + the Exim run-time user may safely pass without dropping privileges. + Because changes to this involve a recompile, this is not the recommended + approach but may ease transition. The values of the macros, when + overridden, are constrained to match this regex: ^[A-Za-z0-9_/.-]*$ + + * The system_filter_user option now defaults to the Exim run-time user, + rather than root. You can still set it explicitly to root and this + can be done with prior versions too, letting you roll versions + without needing to change this configuration option. + + * ClamAV must be at least version 0.95 unless WITH_OLD_CLAMAV_STREAM is + defined at build time. + + +Exim version 4.70 +----------------- + +1. Experimental Yahoo! Domainkeys support has been dropped in this release. +It has been superceded by a native implementation of its successor DKIM. + +2. Up to version 4.69, Exim came with an embedded version of the PCRE library. +As of 4.70, this is no longer the case. To compile Exim, you will need PCRE +installed. Most OS distributions have ready-made library and development +packages. + + +Exim version 4.68 +----------------- + +1. The internal implementation of the database keys that are used for ACL +ratelimiting has been tidied up. This means that an update to 4.68 might cause +Exim to "forget" previous rates that it had calculated, and reset them to zero. + + +Exim version 4.64 +----------------- + +1. Callouts were setting the name used for EHLO/HELO from $smtp_active_ +hostname. This is wrong, because it relates to the incoming message (and +probably the interface on which it is arriving) and not to the outgoing +callout (which could be using a different interface). This has been +changed to use the value of the helo_data option from the smtp transport +instead - this is what is used when a message is actually being sent. If +there is no remote transport (possible with a router that sets up host +addresses), $smtp_active_hostname is used. This change is mentioned here in +case somebody is relying on the use of $smtp_active_hostname. + +2. A bug has been fixed that might just possibly be something that is relied on +in some configurations. In expansion items such as ${if >{xxx}{yyy}...} an +empty string (that is {}) was being interpreted as if it was {0} and therefore +treated as the number zero. From release 4.64, such strings cause an error +because a decimal number, possibly followed by K or M, is required (as has +always been documented). + +3. There has been a change to the GnuTLS support (ChangeLog/PH/20) to improve +Exim's performance. Unfortunately, this has the side effect of being slightly +non-upwards compatible for versions 4.50 and earlier. If you are upgrading from +one of these earlier versions and you use GnuTLS, you must remove the file +called gnutls-params in Exim's spool directory. If you don't do this, you will +see this error: + + TLS error on connection from ... (DH params import): Base64 decoding error. + +Removing the file causes Exim to recompute the relevant encryption parameters +and cache them in the new format that was introduced for release 4.51 (May +2005). If you are upgrading from release 4.51 or later, there should be no +problem. + + Exim version 4.63 -----------------