X-Git-Url: https://git.exim.org/users/jgh/exim.git/blobdiff_plain/8b5af54dcce3034b7893ad66e685a668b3470053..d690cbdcc1eae1eb60e83caf6800f768b733dadd:/src/README.UPDATING?ds=sidebyside diff --git a/src/README.UPDATING b/src/README.UPDATING index 41375584d..8a0533b10 100644 --- a/src/README.UPDATING +++ b/src/README.UPDATING @@ -1,5 +1,3 @@ -$Cambridge: exim/src/README.UPDATING,v 1.2 2005/01/11 15:15:33 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 @@ -28,34 +26,209 @@ 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. + + +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 writable 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 develoment +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 +----------------- + +When an SMTP error message is specified in a "message" modifier in an ACL, or +in a :fail: or :defer: message in a redirect router, Exim now checks the start +of the message for an SMTP error code. This consists of three digits followed +by a space, optionally followed by an extended code of the form n.n.n, also +followed by a space. If this is the case and the very first digit is the same +as the default error code, the code from the message is used instead. If the +very first digit is incorrect, a panic error is logged, and the default code is +used. This is an incompatible change, but it is not expected to affect many (if +any) configurations. It is possible to suppress the use of the supplied code in +a redirect router by setting the smtp_error_code option false. In this case, +any SMTP code is quietly ignored. + + +Exim version 4.61 +----------------- + +1. The default number of ACL variables of each type has been increased to 20, +and it's possible to compile Exim with more. You can safely upgrade to this +release if you already have messages on the queue with saved ACL variable +values. However, if you downgrade from this release with messages on the queue, +any saved ACL values they may have will be lost. + +2. The default value for rfc1413_query_timeout has been changed from 30s to 5s. + + +Exim version 4.54 +----------------- + +There was a problem with 4.52/TF/02 in that a "name=" option on control= +submission terminated at the next slash, thereby not allowing for slashes in +the name. This has been changed so that "name=" takes the rest of the string as +its data. It must therefore be the last option. + + +Version 4.53 +------------ + +If you are using the experimental Domain Keys support, you must upgrade to +at least libdomainkeys 0.67 in order to run this release of Exim. + + +Version 4.51 +------------ + +1. The format in which GnuTLS parameters are cached (in the file gnutls-params +in the spool directory) has been changed. The new format can also be generated +externally, so it is now possible to update the values from outside Exim. This +has been implemented in an upwards, BUT NOT downwards, compatible manner. +Upgrading should be seamless: when Exim finds that it cannot understand an +existing cache file, it generates new parameters and writes them to the cache +in the new format. If, however, you downgrade from 4.51 to a previous release, +you MUST delete the gnutls-params file in the spool directory, because the +older Exim will not recognize the new format. + +2. When doing a callout as part of verifying an address, Exim was not paying +attention to any local part prefix or suffix that was matched by the router +that accepted the address. It now behaves in the same way as it does for +delivery: the affixes are removed from the local part unless +rcpt_include_affixes is set on the transport. If you have a configuration that +uses prefixes or suffixes on addresses that could be used for callouts, and you +want the affixes to be retained, you must make sure that rcpt_include_affixes +is set on the transport. + +3. Bounce and delay warning messages no longer contain details of delivery +errors, except for explicit messages (e.g. generated by :fail:) and SMTP +responses from remote hosts. + + Version 4.50 ------------ -The exicyclog script has been updated to use three-digit numbers in rotated log -files if the maximum number to keep is greater than 99. If you are already -keeping more than 99, there will be an incompatible change when you upgrade. -You will probably want to rename your old log files to the new form before -running the new exicyclog. The following script, by Mick Swisher, can do this -for you: - -# Begin conversion -# Rename all the old files by adding additional leading zeros. -count=99 -while [ $count -gt 0 ]; do -if [ $count -lt 100 ]; then newt=0$count; oldt=$count; fi -if [ $count -lt 10 ]; then newt=00$count; oldt=0$count; fi -if [ -f $mainlog.$oldt ]; then - $mv $mainlog.$oldt $mainlog.$newt -elif [ -f $mainlog.$oldt.$suffix ]; then - $mv $mainlog.$oldt.$suffix $mainlog.$newt.$suffix -fi -if [ -f $rejectlog.$oldt ]; then - $mv $rejectlog.$oldt $rejectlog.$newt -elif [ -f $rejectlog.$oldt.$suffix ]; then - $mv $rejectlog.$oldt.$suffix $rejectlog.$newt.$suffix -fi -count=`expr $count - 1` -done +The exicyclog script has been updated to use three-digit numbers in rotated log +files if the maximum number to keep is greater than 99. If you are already +keeping more than 99, there will be an incompatible change when you upgrade. +You will probably want to rename your old log files to the new form before +running the new exicyclog. Version 4.42