X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/e97957bc478f60d32649b329659d4b72748745c1..1eccaa59eb366c180c36af219a142d8f934f73b0:/doc/doc-txt/NewStuff diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff index f3e34e773..4ee55fdcf 100644 --- a/doc/doc-txt/NewStuff +++ b/doc/doc-txt/NewStuff @@ -1,188 +1,209 @@ -$Cambridge: exim/doc/doc-txt/NewStuff,v 1.96 2006/03/09 15:10:16 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/NewStuff,v 1.115 2006/10/03 15:11:22 ph10 Exp $ New Features in Exim -------------------- -This file contains descriptions of new features that have been added to Exim, -but have not yet made it into the main manual (which is most conveniently -updated when there is a relatively large batch of changes). The doc/ChangeLog -file contains a listing of all changes, including bug fixes. +This file contains descriptions of new features that have been added to Exim. +Before a formal release, there may be quite a lot of detail so that people can +test from the snapshots or the CVS before the documentation is updated. Once +the documentation is updated, this file is reduced to a short list. + + +Version 4.64 +------------ + +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 + log_reject_target = + + The modifier can be used in SMTP and non-SMTP ACLs. It applies to both + permanent and temporary rejections. + +3. There is a new authenticator called "dovecot". This is an interface to the + authentication facility of the Dovecot POP/IMAP server, which can support a + number of authentication methods. If you are using Dovecot to authenticate + POP/IMAP clients, it might be helpful to use the same mechanisms for SMTP + authentication. This is a server authenticator only. The only option is + server_socket, which must specify the socket which is the interface to + Dovecot authentication. The public_name option must specify an + authentication mechanism that Dovecot is configured to support. You can have + several authenticators for different mechanisms. For example: + + dovecot_plain: + driver = dovecot + public_name = PLAIN + server_name = /var/run/dovecot/auth-client + server_setid = $auth1 + + dovecot_ntlm: + driver = dovecot + public_name = NTLM + server_name = /var/run/dovecot/auth-client + server_setid = $auth1 + +4. The variable $message_headers_raw provides a concatenation of all the + messages's headers without any decoding. This is in contrast to + $message_headers, which does RFC2047 decoding on the header contents. + +5. In a DNS black list, when the facility for restricting the matching IP + values is used, the text from the TXT record that is set in $dnslist_text + may not reflect the true reason for rejection. This happens when lists are + merged and the IP address in the A record is used to distinguish them; + unfortunately there is only one TXT record. One way round this is not to use + merged lists, but that can be inefficient because it requires multiple DNS + lookups where one would do in the vast majority of cases when the host of + interest is not on any of the lists. + + A less inefficient way of solving this problem has now been implemented. If + two domain names, comma-separated, are given, the second is used first to do + an initial check, making use of any IP value restrictions that are set. If + there is a match, the first domain is used, without any IP value + restrictions, to get the TXT record. As a byproduct of this, there is also a + check that the IP being tested is indeed on the first list. The first domain + is the one that is put in $dnslist_domain. For example: + + reject message = rejected because $sender_ip_address is blacklisted \ + at $dnslist_domain\n$dnslist_text + dnslists = sbl.spamhaus.org,sbl-xbl.spamhaus.org=127.0.0.2 : \ + dul.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.10 + + For the first blacklist item, this starts by doing a lookup in + sbl-xbl.spamhaus.org and testing for a 127.0.0.2 return. If there is a + match, it then looks in sbl.spamhaus.org, without checking the return value, + and as long as something is found, it looks for the corresponding TXT + record. If there is no match in sbl-xbl.spamhaus.org, nothing more is done. + The second blacklist item is processed similarly. + + If you are interested in more than one merged list, the same list must be + given several times, but because the results of the DNS lookups are cached, + the DNS calls themselves are not repeated. For example: + + reject dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \ + socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3 : \ + misc.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.4 : \ + dul.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.10 + + In this case there is a lookup in dnsbl.sorbs.net, and if none of the IP + values matches (or if no record is found), this is the only lookup that is + done. Only if there is a match is one of the more specific lists consulted. + + +Version 4.63 +------------ + +1. There is a new Boolean option called filter_prepend_home for the redirect + router. + +2. There is a new acl, set by acl_not_smtp_start, which is run right at the + start of receiving a non-SMTP message, before any of the message has been + read. + +3. 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. + +4. There is a new parameter for LDAP lookups called "referrals", which takes + one of the settings "follow" (the default) or "nofollow". + +5. Version 20070721.2 of exipick now included, offering these new options: + --reverse + After all other sorting options have bee processed, reverse order + before displaying messages (-R is synonym). + --random + Randomize order of matching messages before displaying. + --size + Instead of displaying the matching messages, display the sum + of their sizes. + --sort [,...] + Before displaying matching messages, sort the messages according to + each messages value for each variable. + --not + Negate the value for every test (returns inverse output from the + same criteria without --not). + + +Version 4.62 +------------ + +1. The ${readsocket expansion item now supports Internet domain sockets as well + as Unix domain sockets. If the first argument begins "inet:", it must be of + the form "inet:host:port". The port is mandatory; it may be a number or the + name of a TCP port in /etc/services. The host may be a name, or it may be an + IP address. An ip address may optionally be enclosed in square brackets. + This is best for IPv6 addresses. For example: + + ${readsocket{inet:[::1]:1234}{}... + + Only a single host name may be given, but if looking it up yield more than + one IP address, they are each tried in turn until a connection is made. Once + a connection has been made, the behaviour is as for ${readsocket with a Unix + domain socket. + +2. If a redirect router sets up file or pipe deliveries for more than one + incoming address, and the relevant transport has batch_max set greater than + one, a batch delivery now occurs. + +3. The appendfile transport has a new option called maildirfolder_create_regex. + Its value is a regular expression. For a maildir delivery, this is matched + against the maildir directory; if it matches, Exim ensures that a + maildirfolder file is created alongside the new, cur, and tmp directories. + Version 4.61 ------------ -PH/01 There is a new global option called disable_ipv6, which does exactly what - its name implies. If set true, even if the Exim binary has IPv6 support, - no IPv6 activities take place. AAAA records are never looked up for host - names given in manual routing data or elsewhere. AAAA records that are - received from the DNS as additional data for MX records are ignored. Any - IPv6 addresses that are listed in local_interfaces, manualroute route - data, etc. are also ignored. If IP literals are enabled, the ipliteral - router declines to handle IPv6 literal addresses. - -PH/02 There are now 20 of each type of ACL variable by default (instead of 10). - It is also possible to change the numbers by setting ACL_CVARS and/or - ACL_MVARS in Local/Makefile. Backward compatibility is maintained if you - upgrade to this release with existing messages containing ACL variable - settings on the queue. However, going in the other direction - (downgrading) will not be compatible; the values of ACL variables will be - lost. - -PH/03 If quota_warn_message contains a From: header, Exim now refrains from - adding the default one. Similarly, if it contains a Reply-To: header, the - errors_reply_to option, if set, is not used. - -PH/04 The variables $auth1, $auth2, $auth3 are now available in authenticators, - containing the same values as $1, $2, $3. The new variables are provided - because the numerical variables can be reset during string expansions - (for example, during a "match" operation) and so may lose the - authentication data. The preferred variables are now the new ones, with - the use of the numerical ones being deprecated, though the support will - not be removed, at least, not for a long time. - -PH/05 The "control=freeze" ACL modifier can now be followed by /no_tell. If - the global option freeze_tell is set, it is ignored for the current - message (that is, nobody is told about the freezing), provided all the - "control=freeze" modifiers that are obeyed in the current message have - the /no_tell option. - -PH/06 In both GnuTLS and OpenSSL, an expansion of tls_privatekey that results - in an empty string is now treated as unset. - -PH/07 There is a new log selector called sender_verify_fail, which is set by - default. If it is unset, the separate log line that gives details of a - sender verification failure is not written. Log lines for the rejection - of SMTP commands (e.g. RCPT) contain just "sender verify failed", so some - detail is lost. - -PH/08 The default for dns_check_names_pattern now allows slashes within names, - as there are now some PTR records that contain slashes. This check is - only to protect against broken name servers that fall over on strange - characters, so the fact that it applies to all lookups doesn't matter. - -PH/09 The default for rfc4131_query_timeout has been changed from 30s to 5s. - -PH/10 When compiled on FreeBSD, NetBSD, or BSD/OS, the pipe transport has a new - Boolean option called use_classresources, defaulting false. If it is set - true, the setclassresources() function is used to set resource limits - when a pipe transport is run to perform a delivery. The limits for the - uid under which the pipe is to run are obtained from the login class - database. - -PH/11 If retry_interval_max is set greater than 24 hours, it is quietly reset - to 24 hours. This avoids potential overflow problems when processing G - and H retry rules, and it seems reasonable to require a retry at least - once a day. - -PH/12 When the plaintext authenticator is running as a client, the server - challenges are now checked to ensure they are valid base64 strings. The - default action on failure is to abort the authentication. However, if - client_ignore_invalid_base64 is set true, invalid responses are ignored. - -PH/13 When the plaintext authenticator is running as a client, the challenges - from the server are placed in $auth1, $auth2, etc. as they are received. - Thus, the challege that is received in response to sending the first - string (with the AUTH command) can be used in the expansion of the second - string, and so on. Currently, up to 3 challenge strings are available in - this way. If an invalid base64 string is received when client_ignore_ - invalid_base64 is set, an empty string is put in the $auth variable. - -PH/14 Messages created by the autoreply transport now contain a References: - header. This is constructed in accordance with rules that are described - in section 3.64 of RFC 2822, which states that replies should contain - such a header line, and section 3.14 of RFC 3834, which states that - automatic responses are not different in this respect. However, because - some mail processing software does not cope well with very long header - lines, no more than 12 message IDs are copied from the References: header - line in the incoming message. If there are more than 12, the first one - and then the final 11 are copied, before adding the message ID of the - incoming message. - -PH/15 The smtp transport has a new option called authenticated_sender_force. - When set true, it allows the authenticated_sender option's value to be - used, even if Exim has not authenticated as a client. - -PH/16 The expansion ${time_eval:} converts an Exim time string such as - 2d4h1m into a number of seconds. - -PH/17 The ACL modifier control=allow_auth_unadvertised can be used to permit a - client host to use the SMTP AUTH command even when it has not been - advertised in response to EHLO. Furthermore, because there are apparently - some really broken clients that do this, Exim will even accept AUTH after - HELO when this control is set. It should only be used if you really need - it, and you should limit its use to those broken hosts that do not work - without it. For example: - - warn hosts = 192.168.34.25 - control = allow_auth_unadvertised - - This control is permitted only in the connection and HELO ACLs. - -PH/18 There is a new ACL modifier called "add_header" which does what its name - implies. It specifies one of more header lines that are to be added to an - incoming message, assuming, of course, that the message is ultimately - accepted. - - This modifier is permitted in the MAIL, RCPT, PREDATA, DATA, MIME, and - non-SMTP ACLs (in other words, those that are concerned with accepting a - message). Added header lines are accumulated during the MAIL, RCPT, and - PREDATA ACLs, with any duplicates being discarded. They are then added to - the message before processing the DATA and MIME ACLs, during which - further added header lines are accumulated, again with duplicates - discarded. Thus, it is possible to add two identical header lines to an - SMTP message, but only if one is added before DATA and one after. - - In the case of non-SMTP messages, new headers are accumulated during the - non-SMTP ACL, and added to the message at the end. - - The add_header modifier is available for use with all ACL verbs. In the - case of the WARN verb, add_header supersedes the use of "message" for - this purpose; for the other verbs, it provides a new facility. If both - add_header and "message" are present on a WARN verb, both are processed - according to their specifications. - - The add_header modifier acts immediately it is encountered during the - processing of an ACL. This is different to the (now-deprecated) use of - "message" on a WARN verb, where the action is taken only if all the - conditions are true. Notice the difference between these two cases on a - RCPT ACL: - - deny add_header = ADDED: some text - - - deny - add_header = ADDED: some text - - In the first case, the header is always added, whether or not the current - recipient is rejected. In the second case, the header is added only if - the recipient is rejected. - - If add_header appears more than once on an ACL statement, multiple - headers are added, provided that they have different content. (In the - case of WARN with "message", only the last value of "message" is used.) - - The facility for specifying where the new header is to be inserted, as - described for WARN with "message" in section 39.19 of the 4.60 manual, is - supported. - -PH/19 The following errors can now be detected in retry rules: - - mail_4xx This is like rcpt_4xx, but applies to MAIL commands - - data_4xx This is like rcpt_4xx, but applies to DATA commands and the - response code after the end of the data - - lost_connection This error occurs when the server unexpectedly closes - the SMTP connection. There may, of course, legitmate reasons - for this (host died, network died), but if it repeats a lot - for the same host, it indicates something odd. - - tls_required The server was required to use TLS (hosts_require_tls), - but either did not offer it, or responded with 4xx to - STARTTLS, or there was a problem setting up the TLS connection - - Note that a 5xx response to STARTTLS is a permanent error. +The documentation is up-to-date for the 4.61 release. Major new features since +the 4.60 release are: + +. An option called disable_ipv6, to disable the use of IPv6 completely. + +. An increase in the number of ACL variables to 20 of each type. + +. A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1, + $2, $3, (though those are still set) because the numeric variables get used + for other things in complicated expansions. + +. The default for rfc1413_query_timeout has been changed from 30s to 5s. + +. It is possible to use setclassresources() on some BSD OS to control the + resources used in pipe deliveries. + +. A new ACL modifier called add_header, which can be used with any verb. + +. More errors are detectable in retry rules. +There are a number of other additions too. Version 4.60