-PH/01 The format in which GnuTLS parameters are written to the gnutls-param
- file in the spool directory has been changed. This change has been made
- to alleviate problems that some people had with the generation of the
- parameters by Exim when /dev/random was exhausted. In this situation,
- Exim would hang until /dev/random acquired some more entropy.
-
- The new code exports and imports the DH and RSA parameters in PEM
- format. This means that the parameters can be generated externally using
- the certtool command that is part of GnuTLS.
-
- To replace the parameters with new ones, instead of deleting the file
- and letting Exim re-create it, you can generate new parameters using
- certtool and, when this has been done, replace Exim's cache file by
- renaming. The relevant commands are something like this:
-
- # rm -f new.params
- # touch new.params
- # chown exim:exim new.params
- # chmod 0400 new.params
- # certtool --generate-privkey --bits 512 >new.params
- # echo "" >>new.params
- # certtool --generate-dh-params --bits 1024 >> new.params
- # mv new.params params
-
- If Exim never has to generate the parameters itself, the possibility of
- stalling is removed.
-
-PH/02 A new expansion item for dynamically loading and calling a locally-
- written C function is now provided, if Exim is compiled with
-
- EXPAND_DLFUNC=yes
-
- set in Local/Makefile. The facility is not included by default (a
- suitable error is given if you try to use it when it is not there.)
+1. ACL variables can now be given arbitrary names, as long as they start with
+ "acl_c" or "acl_m" (for connection variables and message variables), are
+ at least six characters long, with the sixth character being either a digit
+ or an underscore. The rest of the name can contain alphanumeric characters
+ and underscores. This is a compatible change because the old set of
+ variables such as acl_m12 are a subset of the allowed names. There may now
+ be any number of ACL variables. For example:
+
+ set acl_c13 = value for original ACL variable
+ set acl_c13b = whatever
+ set acl_m_foo = something
+
+ What happens if a syntactically valid but undefined ACL variable is
+ referenced depends on the setting of the strict_acl_vars option. If it is
+ false (the default), an empty string is substituted; if it is true, an error
+ is generated. This affects all ACL variables, including the "old" ones such
+ as acl_c4. (Previously there wasn't the concept of an undefined ACL
+ variable.)
+
+ The implementation has been done in such a way that spool files containing
+ ACL variable settings written by previous releases of Exim are compatible
+ and can be read by the new release. If only the original numeric names are
+ used, spool files written by the new release can be read by earlier
+ releases.
+
+2. There is a new ACL modifier called log_reject_target. It makes it possible
+ to specify which logs are used for messages about ACL rejections. Its
+ argument is a list of words which can be "main", "reject", or "panic". The
+ default is "main:reject". The list may be empty, in which case a rejection
+ is not logged at all. For example, this ACL fragment writes no logging
+ information when access is denied:
+
+ deny <some conditions>
+ log_reject_target =
+
+ The modifier can be used in SMTP and non-SMTP ACLs. It applies to both
+ permanent and temporary rejections.
+
+
+Version 4.63
+------------