X-Git-Url: https://git.exim.org/users/jgh/exim.git/blobdiff_plain/8800895ae8a1e9c49c739839a6623292d7a473d0..d78371933afdcbdb420e40a2855b548a4673dc3d:/doc/doc-txt/NewStuff?ds=inline diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff index 15cf0b44d..67901a28c 100644 --- a/doc/doc-txt/NewStuff +++ b/doc/doc-txt/NewStuff @@ -1,721 +1,355 @@ -$Cambridge: exim/doc/doc-txt/NewStuff,v 1.67 2005/09/12 10:08:53 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/NewStuff,v 1.123 2006/11/14 16:40:36 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. -Exim version 4.53 ------------------ - -TK/01 Added the "success_on_redirect" address verification option. When an - address generates new addresses during routing, Exim will abort - verification with "success" when more than one address has been - generated, but continue to verify a single new address. The latter - does not happen when the new "success_on_redirect" option is set, like - - require verify = recipient/success_on_redirect/callout=10s - - In that case, verification will succeed when a router generates a new - address. - -PH/01 Support for SQLite database lookups has been added. This is another - query-style lookup, but it is slightly different from the others because - a file name is required in addition to the SQL query. This is because an - SQLite database is a single file and there is no daemon as in other SQL - databases. The interface to Exim requires the name of the file, as an - absolute path, to be given at the start of the query. It is separated - from the query by white space. This means that the path name cannot - contain white space. Here is a lookup expansion example: - - ${lookup sqlite {/some/thing/sqlitedb \ - select name from aliases where id='ph10';}} - - In a list, the syntax is similar. For example: - domainlist relay_domains = sqlite;/some/thing/sqlitedb \ - select * from relays where ip='$sender_host_address'; - - The only character affected by the ${quote_sqlite: operator is a single - quote, which it doubles. - - The SQLite library handles multiple simultaneous accesses to the database - internally. Multiple readers are permitted, but only one process can - update at once. Attempts to access the database while it is being updated - are rejected after a timeout period, during which the SQLite library - waits for the lock to be released. In Exim, the default timeout is set - to 5 seconds, but it can be changed by means of the sqlite_lock_timeout - option. - - Note that you must set LOOKUP_SQLITE=yes in Local/Makefile in order to - obtain SQLite support, and you will also need to add -lsqlite3 to the - EXTRALIBS setting. And of course, you have to install SQLite on your - host first. - -PH/02 The variable $message_id is now deprecated, to be replaced by - $message_exim_id, which makes it clearer which ID is being referenced. - -PH/03 The use of forbid_filter_existstest now also locks out the use of the - ${stat: expansion item. - -PH/04 The IGNOREQUOTA extension to the LMTP protocol is now available in both - the lmtp transport and the smtp transport running in LMTP mode. In the - lmtp transport there is a new Boolean option called ignore_quota, and in - the smtp transport there is a new Boolean option called - lmtp_ignore_quota. If either of these options is set TRUE, the string - "IGNOREQUOTA" is added to RCPT commands when using the LMTP protocol, - provided that the server has advertised support for IGNOREQUOTA in its - response to the LHLO command. - -PH/05 Previously, if "verify = helo" was set in an ACL, the condition was true - only if the host matched helo_try_verify_hosts, which caused the - verification to occur when the EHLO/HELO command was issued. The ACL just - tested the remembered result. Now, if a previous verification attempt has - not happened, "verify = helo" does it there and then. - -PH/06 It is now possible to specify a port number along with a host name or - IP address in the list of hosts defined in the manualroute or - queryprogram routers, fallback_hosts, or the "hosts" option of the smtp - transport. These all override any port specification on the transport. - The relatively standard syntax of using a colon separator has been - adopted, but there are some gotchas that need attention: - - * In all these lists of hosts, colon is the default separator, so either - the colon that specifies a port must be doubled, or the separator must - be changed. The following two examples have the same effect: - - fallback_hosts = host1.tld::1225 : host2.tld::1226 - fallback_hosts = <; host1.tld:1225 ; host2.tld:1226 - - * When IPv6 addresses are involved, it gets worse, because they contain - colons of their own. To make this case easier, it is permitted to - enclose an IP address (either v4 or v6) in square brackets if a port - number follows. Here's an example from a manualroute router: - - route_list = * " - -TF/03 The control = fakereject ACL modifier now has a fakedefer counterpart, - which works in exactly the same way except it causes a fake SMTP 450 - response after the message data instead of a fake SMTP 550 response. - You must take care when using fakedefer because it will cause messages - to be duplicated when the sender retries. Therefore you should not use - fakedefer if the message will be delivered normally. - -TF/04 There is a new ratelimit ACL condition which can be used to measure - and control the rate at which clients can send email. This is more - powerful than the existing smtp_ratelimit_* options, because those - options only control the rate of commands in a single SMTP session, - whereas the new ratelimit condition works across all connections - (concurrent and sequential) to the same host. - - The syntax of the ratelimit condition is: - - ratelimit = /

/ / - - If the average client sending rate is less than m messages per time - period p then the condition is false, otherwise it is true. - - The parameter p is the smoothing time constant, in the form of an Exim - time interval e.g. 8h for eight hours. A larger time constant means it - takes Exim longer to forget a client's past behaviour. The parameter m is - the maximum number of messages that a client can send in a fast burst. By - increasing both m and p but keeping m/p constant, you can allow a client - to send more messages in a burst without changing its overall sending - rate limit. Conversely, if m and p are both small then messages must be - sent at an even rate. - - The key is used to look up the data used to calcluate the client's - average sending rate. This data is stored in a database maintained by - Exim in its spool directory alongside the retry database etc. For - example, you can limit the sending rate of each authenticated user, - independent of the computer they are sending from, by setting the key - to $authenticated_id. The default key is $sender_host_address. - Internally, Exim includes the smoothing constant p and the options in - the lookup key because they alter the meaning of the stored data. - This is not true for the limit m, so you can alter the configured - maximum rate and Exim will still remember clients' past behaviour, - but if you alter the other ratelimit parameters Exim will effectively - forget their past behaviour. - - Each ratelimit condition can have up to two options. The first option - specifies what Exim measures the rate of, and the second specifies how - Exim handles excessively fast clients. - - The per_mail option means that it measures the client's rate of sending - messages. This is the default if none of the per_* options is specified. - - The per_conn option means that it measures the client's connection rate. - - The per_byte option limits the sender's email bandwidth. Note that it - is best to use this option in the DATA ACL; if it is used in an earlier - ACL it relies on the SIZE parameter on the MAIL command, which may be - inaccurate or completely missing. You can follow the limit m in the - configuration with K, M, or G to specify limits in kilobytes, - megabytes, or gigabytes respectively. - - The per_cmd option means that Exim recomputes the rate every time the - condition is processed, which can be used to limit the SMTP command rate. - The alias per_rcpt is provided for use in the RCPT ACL instead of per_cmd - to make it clear that the effect is to limit the rate at which recipients - are accepted. Note that in this case the rate limiting engine will see a - message with many recipients as a large high-speed burst. - - If a client's average rate is greater than the maximum, the rate - limiting engine can react in two possible ways, depending on the - presence of the strict or leaky options. This is independent of the - other counter-measures (e.g. rejecting the message) that may be - specified by the rest of the ACL. The default mode is leaky, which - avoids a sender's over-aggressive retry rate preventing it from getting - any email through. - - The strict option means that the client's recorded rate is always - updated. The effect of this is that Exim measures the client's average - rate of attempts to send email, which can be much higher than the - maximum. If the client is over the limit it will be subjected to - counter-measures until it slows down below the maximum rate. - - The leaky option means that the client's recorded rate is not updated - if it is above the limit. The effect of this is that Exim measures the - client's average rate of successfully sent email, which cannot be - greater than the maximum. If the client is over the limit it will - suffer some counter-measures, but it will still be able to send email - at the configured maximum rate, whatever the rate of its attempts. - - As a side-effect, the ratelimit condition will set the expansion - variables $sender_rate containing the client's computed rate, - $sender_rate_limit containing the configured value of m, and - $sender_rate_period containing the configured value of p. - - Exim's other ACL facilities are used to define what counter-measures - are taken when the rate limit is exceeded. This might be anything from - logging a warning (e.g. while measuring existing sending rates in order - to define our policy), through time delays to slow down fast senders, - up to rejecting the message. For example, - - # Log all senders' rates - warn - ratelimit = 0 / 1h / strict - log_message = \ - Sender rate $sender_rate > $sender_rate_limit / $sender_rate_period - - # Slow down fast senders - warn - ratelimit = 100 / 1h / per_rcpt / strict - delay = ${eval: 10 * ($sender_rate - $sender_rate_limit) } - - # Keep authenticated users under control - deny - ratelimit = 100 / 1d / strict / $authenticated_id - - # System-wide rate limit - defer - message = Sorry, too busy. Try again later. - ratelimit = 10 / 1s / $primary_hostname - - # Restrict incoming rate from each host, with a default rate limit - # set using a macro and special cases looked up in a table. - defer - message = Sender rate $sender_rate exceeds \ - $sender_rate_limit messages per $sender_rate_period - ratelimit = ${lookup {$sender_host_address} \ - cdb {DB/ratelimits.cdb} \ - {$value} {RATELIMIT} } - - Warning: if you have a busy server with a lot of ratelimit tests, - especially with the per_rcpt option, you may suffer from a performance - bottleneck caused by locking on the ratelimit hints database. Apart from - making your ACLs less complicated, you can reduce the problem by using a - RAM disk for Exim's hints directory, /var/spool/exim/db/. However this - means that Exim will lose its hints data after a reboot (including retry - hints, the callout cache, and ratelimit data). - -TK/01 Added an 'spf' lookup type that will return an SPF result for a given - email address (the key) and an IP address (the database): - - ${lookup {tom@duncanthrax.net} spf{217.115.139.137}} - - The lookup will return the same result strings as they can appear in - $spf_result (pass,fail,softfail,neutral,none,err_perm,err_temp). The - lookup is armored in EXPERIMENTAL_SPF. Currently, only IPv4 addresses - are supported. - - Patch submitted by Chris Webb . - -PH/02 There's a new verify callout option, "fullpostmaster", which first acts - as "postmaster" and checks the recipient . If that - fails, it tries just , without a domain, in accordance with - the specification in RFC 2821. - -PH/03 The action of the auto_thaw option has been changed. It no longer applies - to frozen bounce messages. - -TK/02 There are two new expansion items to help with the implementation of - the BATV "prvs" scheme in an Exim configuration: - - - ${prvs {

}{}{[KEYNUM]}} - - The "prvs" expansion item takes three arguments: A qualified RFC2821 - email address, a key and an (optional) key number. All arguments are - expanded before being used, so it is easily possible to lookup a key - and key number using the address as the lookup key. The key number is - optional and defaults to "0". The item will expand to a "prvs"-signed - email address, to be typically used with the "return_path" option on - a smtp transport. The decision if BATV should be used with a given - sender/recipient pair should be done on router level, to avoid having - to set "max_rcpt = 1" on the transport. - - - ${prvscheck {
}{}{}} - - The "prvscheck" expansion item takes three arguments. Argument 1 is - expanded first. When the expansion does not yield a SYNTACTICALLY - valid "prvs"-scheme address, the whole "prvscheck" item expands to - the empty string. If
is a "prvs"-encoded address after - expansion, two expansion variables are set up: - - $prvscheck_address Contains the "prvs"-decoded version of - the address from argument 1. - - $prvscheck_keynum Contains the key number extracted from - the "prvs"-address in argument 1. - - These two variables can be used in the expansion code of argument 2 - to retrieve the . The VALIDITY of the "prvs"-signed address - is then checked. The result is stored in yet another expansion - variable: - - $prvscheck_result Contains the result of a "prvscheck" - expansion: Unset (the empty string) for - failure, "1" for success. - - The "prvscheck" expansion expands to the empty string if
- is not a SYNTACTICALLY valid "prvs"-scheme address. Otherwise, - argument 3 defines what "prvscheck" expands to: If argument 3 - is the empty string, "prvscheck" expands to the decoded version - of the address (no matter if it is CRYPTOGRAPHICALLY valid or not). - If argument 3 expands to a non-empty string, "prvscheck" expands - to that string. - - - Usage example - ------------- - - Macro: - - PRVSCHECK_SQL = ${lookup mysql{SELECT secret FROM batv_prvs WHERE \ - sender='${quote_mysql:$prvscheck_address}'}{$value}} - - RCPT ACL: - - # Bounces: drop unsigned addresses for BATV senders - deny message = This address does not send an unsigned reverse path. - senders = : - recipients = +batv_recipients - - # Bounces: In case of prvs-signed address, check signature. - deny message = Invalid reverse path signature. - senders = : - condition = ${prvscheck {$local_part@$domain}{PRVSCHECK_SQL}{1}} - !condition = $prvscheck_result +Version 4.64 +------------ - Top-Level Router: + 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 + + If the SMTP connection is encrypted, or if $sender_host_address is equal to + $interface_address (that is, the connection is local), the "secured" option + is passed in the Dovecot authentication command. If, for a TLS connection, + a client certificate has been verified, the "valid-client-cert" option is + passed. + + 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. + + 6. All authenticators now have a server_condition option. Previously, only + plaintext had this, and this has not changed: it must be set to the + authenticator as a server. For the others, if server_condition is set, it + is expanded if authentication is successful, and treated exactly as it is + in plaintext. This can serve as a means of adding authorization to an + authenticator. + + 7. There is a new command-line option called -Mset. It is useful only in + conjunction with -be (that is, when testing string expansions). It must be + followed by a message id; Exim loads the given message from its spool + before doing the expansions, thus setting message-specific variables such + as $message_size and the header variables. The $recipients variable is + available. This feature is provided to make it easier to test expansions + that make use of these variables. However, Exim must be called by an admin + user when -Mset is used. + + 8. Another similar new command-line option is called -bem. It operates like + -be except that it must be followed by the name of a file. For example: + + exim -bem /tmp/testmessage + + The file is read as a message (as if receiving a locally-submitted non-SMTP + message) before any of the test expansions are done. Thus, message-specific + variables such as $message_size and $h_from: are available. However, no + Received: header is added to the message. If the -t option is set, + recipients are read from the headers in the normal way, and are shown in + the $recipients variable. Note that recipients cannot be given on the + command line, because further arguments are taken as strings to expand + (just like -be). + + 9. When an address is delayed because of a 4xx response to a RCPT command, it + is now the combination of sender and recipient that is delayed in + subsequent queue runs until its retry time is reached. You can revert to + the previous behavious, that is, delay the recipient independent of the + sender, by setting address_retry_include_sender=false in the smtp + transport. However, this can lead to problems with servers that regularly + issue 4xx responses to RCPT commands. + +10. Unary negation and the bitwise logical operators and, or, xor, not, and + shift, have been added to the eval: and eval10: expansion items. These + items may now contain arithmetic operators (plus, minus, times, divide, + remainder, negate), bitwise operators (and, or, xor, not, shift), and + parentheses. All operations are carried out using signed integer + arithmetic. Operator priorities are as in C, namely: + + (highest) not, negate + times, divide, remainder + plus, minus + shift-left, shift-right + and + xor + (lowest) or + + Binary operators with the same priority are evaluated from left to right. + For example: + + ${eval:1+1} yields 2 + ${eval:1+2*3} yields 7 + ${eval:(1+2)*3} yields 9 + ${eval:2+42%5} yields 4 + ${eval:0xc&5} yields 4 + ${eval:0xc|5} yields 13 + ${eval:0xc^5} yields 9 + ${eval:0xc>>1} yields 6 + ${eval:0xc<<1} yields 24 + ${eval:~255&0x1234} yields 4608 + ${eval:-(~255&0x1234)} yields -4608 + +11. The variables $interface_address and $interface_port have been renamed + as $received_ip_address and $received_port, to make it clear that they + relate to message reception rather than delivery. (The old names remain + available for compatibility.) + +12. The "message" modifier can now be used on acl verbs to vary the message + that is sent when an SMTP command. For example, in a RCPT ACL you could + have: + + accept + message = OK, I'll allow you through today + + Previously, this message modifier would have had no effect whatsoever. + + IMPORTANT: The new behaviour applies to "accept" (and "discard") only if + there is no occurrence of "endpass" in the statement. If "endpass" is + present, the behaviour reverts to the old case, where "message" applies to + rejection. This is for backwards compatibility. + + It is always possible to rewrite ACL statements so that "endpass" is not + needed (and indeed it is no longer used in the default configuration, and + is somewhat not recommended nowadays because it causes confusion.) + + It is now generally true that the "message" modifier sets up a text string + that is expanded and used as a response message if the current statement + terminates the ACL. The expansion happens at the time Exim decides that the + ACL is to end, not at the time it processes "message". If the expansion + fails, or generates an empty string, the modifier is ignored. + + For ACLs that are triggered by SMTP commands, the message is returned as + part of the SMTP response. In this situation, the message may begin with an + overriding SMTP response code, optionally followed by an "extended response + code". However, the first digit of the supplied response code must be the + same as would be sent by default. A panic occurs if it is not. For the + predata ACL, note that the default success code is 354, not 2xx. + + However, notwithstanding the previous paragraph, for the QUIT ACL, unlike + the others, the message modifier cannot override the 221 response code. + + In the case of the "connect" ACL, accepting with a message modifier + overrides the value of smtp_banner. + + The ACL test specified by acl_smtp_helo happens when the client issues the + HELO or EHLO commands, after the tests specified by helo_accept_junk_hosts, + helo_allow_chars and helo(_try)_verify_hosts. An acceptance message + modifier for EHLO/HELO may not contain more than one line (it will be + truncated at the first newline and a panic logged), and it cannot affect + the EHLO options. + + + +Version 4.63 +------------ - batv_redirect: - driver = redirect - data = ${prvscheck {$local_part@$domain}{PRVSCHECK_SQL}{}} +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 +------------ - Transport (referenced by router that makes decision if - BATV is applicable): +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: - external_smtp_batv: - driver = smtp - return_path = ${prvs {$return_path} \ - {${lookup mysql{SELECT \ - secret FROM batv_prvs WHERE \ - sender='${quote_mysql:$sender_address}'} \ - {$value}fail}}} + ${readsocket{inet:[::1]:1234}{}... -PH/04 There are two new options that control the retrying done by the daemon - at startup when it cannot immediately bind a socket (typically because - the socket is already in use). The default values reproduce what were - built-in constants previously: daemon_startup_retries defines the number - of retries after the first failure (default 9); daemon_startup_sleep - defines the length of time to wait between retries (default 30s). + 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. -PH/05 There is now a new ${if condition called "match_ip". It is similar to - match_domain, etc. It must be followed by two argument strings. The first - (after expansion) must be an IP address or an empty string. The second - (after expansion) is a restricted host list that can match only an IP - address, not a host name. For example: +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. - ${if match_ip{$sender_host_address}{1.2.3.4:5.6.7.8}{...}{...}} +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. - The specific types of host list item that are permitted in the list are - shown below. Consult the manual section on host lists for further - details. - . An IP address, optionally with a CIDR mask. +Version 4.61 +------------ - . A single asterisk matches any IP address. +The documentation is up-to-date for the 4.61 release. Major new features since +the 4.60 release are: - . An empty item matches only if the IP address is empty. This could be - useful for testing for a locally submitted message or one from specific - hosts in a single test such as +. An option called disable_ipv6, to disable the use of IPv6 completely. - ${if match_ip{$sender_host_address}{:4.3.2.1:...}{...}{...}} +. An increase in the number of ACL variables to 20 of each type. - where the first item in the list is the empty string. +. 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 item @[] matches any of the local host's interface addresses. +. The default for rfc1413_query_timeout has been changed from 30s to 5s. - . Lookups are assumed to be "net-" style lookups, even if "net-" is not - specified. Thus, the following are equivalent: +. It is possible to use setclassresources() on some BSD OS to control the + resources used in pipe deliveries. - ${if match_ip{$sender_host_address}{lsearch;/some/file}... - ${if match_ip{$sender_host_address}{net-lsearch;/some/file}... +. A new ACL modifier called add_header, which can be used with any verb. - You do need to specify the "net-" prefix if you want to specify a - specific address mask, for example, by using "net24-". +. More errors are detectable in retry rules. -PH/06 The "+all" debug selector used to set the flags for all possible output; - it is something that people tend to use semi-automatically when - generating debug output for me or for the list. However, by including - "+memory", an awful lot of output that is very rarely of interest was - generated. I have changed this so that "+all" no longer includes - "+memory". However, "-all" still turns everything off. +There are a number of other additions too. -Version 4.51 +Version 4.60 ------------ -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 documentation is up-to-date for the 4.60 release. Major new features since +the 4.50 release are: - 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. +. Support for SQLite. - 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: +. Support for IGNOREQUOTA in LMTP. - # 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 +. Extensions to the "submission mode" features. - If Exim never has to generate the parameters itself, the possibility of - stalling is removed. +. Support for Client SMTP Authorization (CSA). -PH/02 A new expansion item for dynamically loading and calling a locally- - written C function is now provided, if Exim is compiled with +. Support for ratelimiting hosts and users. - EXPAND_DLFUNC=yes +. New expansion items to help with the BATV "prvs" scheme. - 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.) - - If you enable EXPAND_DLFUNC, you should also be aware of the new redirect - router option forbid_filter_dlfunc. If you have unprivileged users on - your system who are permitted to create filter files, you might want to - set forbid_filter_dlfunc=true in the appropriate router, to stop them - using ${dlfunc to run code within Exim. - - You load and call an external function like this: - - ${dlfunc{/some/file}{function}{arg1}{arg2}...} - - Once loaded, Exim remembers the dynamically loaded object so that it - doesn't reload the same object file in the same Exim process (but of - course Exim does start new processes frequently). - - There may be from zero to eight arguments to the function. When compiling - a local function that is to be called in this way, local_scan.h should be - included. The Exim variables and functions that are defined by that API - are also available for dynamically loaded functions. The function itself - must have the following type: - - int dlfunction(uschar **yield, int argc, uschar *argv[]) - - Where "uschar" is a typedef for "unsigned char" in local_scan.h. The - function should return one of the following values: - - OK Success. The string that is placed in "yield" is put into - the expanded string that is being built. - - FAIL A non-forced expansion failure occurs, with the error - message taken from "yield", if it is set. - - FAIL_FORCED A forced expansion failure occurs, with the error message - taken from "yield" if it is set. - - ERROR Same as FAIL, except that a panic log entry is written. - - When compiling a function that is to be used in this way with gcc, - you need to add -shared to the gcc command. Also, in the Exim build-time - configuration, you must add -export-dynamic to EXTRALIBS. - -TF/01 $received_time is a new expansion variable containing the time and date - as a number of seconds since the start of the Unix epoch when the - current message was received. - -PH/03 There is a new value for RADIUS_LIB_TYPE that can be set in - Local/Makefile. It is RADIUSCLIENTNEW, and it requests that the new API, - in use from radiusclient 0.4.0 onwards, be used. It does not appear to be - possible to detect the different versions automatically. - -PH/04 There is a new option called acl_not_smtp_mime that allows you to scan - MIME parts in non-SMTP messages. It operates in exactly the same way as - acl_smtp_mime - -PH/05 It is now possible to redefine a macro within the configuration file. - The macro must have been previously defined within the configuration (or - an included file). A definition on the command line using the -D option - causes all definitions and redefinitions within the file to be ignored. - In other words, -D overrides any values that are set in the file. - Redefinition is specified by using '==' instead of '='. For example: - - MAC1 = initial value - ... - MAC1 == updated value - - Redefinition does not alter the order in which the macros are applied to - the subsequent lines of the configuration file. It is still the same - order in which the macros were originally defined. All that changes is - the macro's value. Redefinition makes it possible to accumulate values. - For example: - - MAC1 = initial value - ... - MAC1 == MAC1 and something added - - This can be helpful in situations where the configuration file is built - from a number of other files. - -PH/06 Macros may now be defined or redefined between router, transport, - authenticator, or ACL definitions, as well as in the main part of the - configuration. They may not, however, be changed within an individual - driver or ACL, or in the local_scan, retry, or rewrite sections of the - configuration. - -PH/07 $acl_verify_message is now set immediately after the failure of a - verification in an ACL, and so is available in subsequent modifiers. In - particular, the message can be preserved by coding like this: - - warn !verify = sender - set acl_m0 = $acl_verify_message - - Previously, $acl_verify_message was set only while expanding "message" - and "log_message" when a very denied access. - -PH/08 The redirect router has two new options, sieve_useraddress and - sieve_subaddress. These are passed to a Sieve filter to specify the :user - and :subaddress parts of an address. Both options are unset by default. - However, when a Sieve filter is run, if sieve_useraddress is unset, the - entire original local part (including any prefix or suffix) is used for - :user. An unset subaddress is treated as an empty subaddress. - -PH/09 Quota values can be followed by G as well as K and M. - -PH/10 $message_linecount is a new variable that contains the total number of - lines in the header and body of the message. Compare $body_linecount, - which is the count for the body only. During the DATA and - content-scanning ACLs, $message_linecount contains the number of lines - received. Before delivery happens (that is, before filters, routers, and - transports run) the count is increased to include the Received: header - line that Exim standardly adds, and also any other header lines that are - added by ACLs. The blank line that separates the message header from the - body is not counted. Here is an example of the use of this variable in a - DATA ACL: - - deny message = Too many lines in message header - condition = \ - ${if <{250}{${eval: $message_linecount - $body_linecount}}} - - In the MAIL and RCPT ACLs, the value is zero because at that stage the - message has not yet been received. - -PH/11 In a ${run expansion, the variable $value (which contains the standard - output) is now also usable in the "else" string. - -PH/12 In a pipe transport, although a timeout while waiting for the pipe - process to complete was treated as a delivery failure, a timeout while - writing the message to the pipe was logged, but erroneously treated as a - successful delivery. Such timeouts include transport filter timeouts. For - consistency with the overall process timeout, these timeouts are now - treated as errors, giving rise to delivery failures by default. However, - there is now a new Boolean option for the pipe transport called - timeout_defer, which, if set TRUE, converts the failures into defers for - both kinds of timeout. A transport filter timeout is now identified in - the log output. - - -Version 4.50 ------------- +. A "match_ip" condition, that matches an IP address against a list. -The documentation is up-to-date for the 4.50 release. +There are many more minor changes. ****