| 1 | $Cambridge: exim/doc/doc-txt/NewStuff,v 1.161 2009/11/16 19:06:35 nm4 Exp $ |
| 2 | |
| 3 | New Features in Exim |
| 4 | -------------------- |
| 5 | |
| 6 | This file contains descriptions of new features that have been added to Exim. |
| 7 | Before a formal release, there may be quite a lot of detail so that people can |
| 8 | test from the snapshots or the CVS before the documentation is updated. Once |
| 9 | the documentation is updated, this file is reduced to a short list. |
| 10 | |
| 11 | |
| 12 | Version 4.70 / 4.71 |
| 13 | ------------------- |
| 14 | |
| 15 | 1. Native DKIM support without an external library. |
| 16 | |
| 17 | 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha). |
| 18 | |
| 19 | 3. There is now a bool{} expansion condition which maps certain strings to |
| 20 | true/false condition values (most likely of use in conjuction with the |
| 21 | and{} expansion operator). |
| 22 | |
| 23 | 4. The $spam_score, $spam_bar and $spam_report variables are now available |
| 24 | at delivery time. |
| 25 | |
| 26 | 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as |
| 27 | options, provided that Exim is invoked by an admin_user. |
| 28 | |
| 29 | 6. There is a new option gnutls_compat_mode, when linked against GnuTLS, |
| 30 | which increases compatibility with older clients at the cost of decreased |
| 31 | security. Don't set this unless you need to support such clients. |
| 32 | |
| 33 | 7. There is a new expansion operator, ${randint:...} which will produce a |
| 34 | "random" number less than the supplied integer. This randomness is |
| 35 | not guaranteed to be cryptographically strong, but depending upon how |
| 36 | Exim was built may be better than the most naive schemes. |
| 37 | |
| 38 | 8. Exim now explicitly ensures that SHA256 is available when linked against |
| 39 | OpenSSL. |
| 40 | |
| 41 | 9. The transport_filter_timeout option now applies to SMTP transports too. |
| 42 | |
| 43 | |
| 44 | Version 4.68 |
| 45 | ------------ |
| 46 | |
| 47 | 1. The body_linecount and body_zerocount C variables are now exported in the |
| 48 | local_scan API. |
| 49 | |
| 50 | 2. When a dnslists lookup succeeds, the key that was looked up is now placed |
| 51 | in $dnslist_matched. When the key is an IP address, it is not reversed in |
| 52 | this variable (though it is, of course, in the actual lookup). In simple |
| 53 | cases, for example: |
| 54 | |
| 55 | deny dnslists = spamhaus.example |
| 56 | |
| 57 | the key is also available in another variable (in this case, |
| 58 | $sender_host_address). In more complicated cases, however, this is not |
| 59 | true. For example, using a data lookup might generate a dnslists lookup |
| 60 | like this: |
| 61 | |
| 62 | deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|... |
| 63 | |
| 64 | If this condition succeeds, the value in $dnslist_matched might be |
| 65 | 192.168.6.7 (for example). |
| 66 | |
| 67 | 3. Authenticators now have a client_condition option. When Exim is running as |
| 68 | a client, it skips an authenticator whose client_condition expansion yields |
| 69 | "0", "no", or "false". This can be used, for example, to skip plain text |
| 70 | authenticators when the connection is not encrypted by a setting such as: |
| 71 | |
| 72 | client_condition = ${if !eq{$tls_cipher}{}} |
| 73 | |
| 74 | Note that the 4.67 documentation states that $tls_cipher contains the |
| 75 | cipher used for incoming messages. In fact, during SMTP delivery, it |
| 76 | contains the cipher used for the delivery. The same is true for |
| 77 | $tls_peerdn. |
| 78 | |
| 79 | 4. There is now a -Mvc <message-id> option, which outputs a copy of the |
| 80 | message to the standard output, in RFC 2822 format. The option can be used |
| 81 | only by an admin user. |
| 82 | |
| 83 | 5. There is now a /noupdate option for the ratelimit ACL condition. It |
| 84 | computes the rate and checks the limit as normal, but it does not update |
| 85 | the saved data. This means that, in relevant ACLs, it is possible to lookup |
| 86 | the existence of a specified (or auto-generated) ratelimit key without |
| 87 | incrementing the ratelimit counter for that key. |
| 88 | |
| 89 | In order for this to be useful, another ACL entry must set the rate |
| 90 | for the same key somewhere (otherwise it will always be zero). |
| 91 | |
| 92 | Example: |
| 93 | |
| 94 | acl_check_connect: |
| 95 | # Read the rate; if it doesn't exist or is below the maximum |
| 96 | # we update it below |
| 97 | deny ratelimit = 100 / 5m / strict / noupdate |
| 98 | log_message = RATE: $sender_rate / $sender_rate_period \ |
| 99 | (max $sender_rate_limit) |
| 100 | |
| 101 | [... some other logic and tests...] |
| 102 | |
| 103 | warn ratelimit = 100 / 5m / strict / per_cmd |
| 104 | log_message = RATE UPDATE: $sender_rate / $sender_rate_period \ |
| 105 | (max $sender_rate_limit) |
| 106 | condition = ${if le{$sender_rate}{$sender_rate_limit}} |
| 107 | |
| 108 | accept |
| 109 | |
| 110 | 6. The variable $max_received_linelength contains the number of bytes in the |
| 111 | longest line that was received as part of the message, not counting the |
| 112 | line termination character(s). |
| 113 | |
| 114 | 7. Host lists can now include +ignore_defer and +include_defer, analagous to |
| 115 | +ignore_unknown and +include_unknown. These options should be used with |
| 116 | care, probably only in non-critical host lists such as whitelists. |
| 117 | |
| 118 | 8. There's a new option called queue_only_load_latch, which defaults true. |
| 119 | If set false when queue_only_load is greater than zero, Exim re-evaluates |
| 120 | the load for each incoming message in an SMTP session. Otherwise, once one |
| 121 | message is queued, the remainder are also. |
| 122 | |
| 123 | 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most |
| 124 | cases when an SMTP session ends without sending QUIT. However, when Exim |
| 125 | itself is is bad trouble, such as being unable to write to its log files, |
| 126 | this ACL is not run, because it might try to do things (such as write to |
| 127 | log files) that make the situation even worse. |
| 128 | |
| 129 | Like the QUIT ACL, this new ACL is provided to make it possible to gather |
| 130 | statistics. Whatever it returns (accept or deny) is immaterial. The "delay" |
| 131 | modifier is forbidden in this ACL. |
| 132 | |
| 133 | When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set |
| 134 | to a string that indicates the reason for the termination of the SMTP |
| 135 | connection. The possible values are: |
| 136 | |
| 137 | acl-drop Another ACL issued a "drop" command |
| 138 | bad-commands Too many unknown or non-mail commands |
| 139 | command-timeout Timeout while reading SMTP commands |
| 140 | connection-lost The SMTP connection has been lost |
| 141 | data-timeout Timeout while reading message data |
| 142 | local-scan-error The local_scan() function crashed |
| 143 | local-scan-timeout The local_scan() function timed out |
| 144 | signal-exit SIGTERM or SIGINT |
| 145 | synchronization-error SMTP synchronization error |
| 146 | tls-failed TLS failed to start |
| 147 | |
| 148 | In most cases when an SMTP connection is closed without having received |
| 149 | QUIT, Exim sends an SMTP response message before actually closing the |
| 150 | connection. With the exception of acl-drop, the default message can be |
| 151 | overridden by the "message" modifier in the NOTQUIT ACL. In the case of a |
| 152 | "drop" verb in another ACL, it is the message from the other ACL that is |
| 153 | used. |
| 154 | |
| 155 | 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of |
| 156 | servers with individual queries. This is done by starting the query with |
| 157 | "servers=x:y:z;", where each item in the list may take one of two forms: |
| 158 | |
| 159 | (1) If it is just a host name, the appropriate global option (mysql_servers |
| 160 | or pgsql_servers) is searched for a host of the same name, and the |
| 161 | remaining parameters (database, user, password) are taken from there. |
| 162 | |
| 163 | (2) If it contains any slashes, it is taken as a complete parameter set. |
| 164 | |
| 165 | The list of servers is used in exactly the same was as the global list. |
| 166 | Once a connection to a server has happened and a query has been |
| 167 | successfully executed, processing of the lookup ceases. |
| 168 | |
| 169 | This feature is intended for use in master/slave situations where updates |
| 170 | are occurring, and one wants to update a master rather than a slave. If the |
| 171 | masters are in the list for reading, you might have: |
| 172 | |
| 173 | mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw |
| 174 | |
| 175 | In an updating lookup, you could then write |
| 176 | |
| 177 | ${lookup mysql{servers=master; UPDATE ...} |
| 178 | |
| 179 | If, on the other hand, the master is not to be used for reading lookups: |
| 180 | |
| 181 | pgsql_servers = slave1/db/name/pw:slave2/db/name/pw |
| 182 | |
| 183 | you can still update the master by |
| 184 | |
| 185 | ${lookup pgsql{servers=master/db/name/pw; UPDATE ...} |
| 186 | |
| 187 | 11. The message_body_newlines option (default FALSE, for backwards |
| 188 | compatibility) can be used to control whether newlines are present in |
| 189 | $message_body and $message_body_end. If it is FALSE, they are replaced by |
| 190 | spaces. |
| 191 | |
| 192 | |
| 193 | Version 4.67 |
| 194 | ------------ |
| 195 | |
| 196 | 1. There is a new log selector called smtp_no_mail, which is not included in |
| 197 | the default setting. When it is set, a line is written to the main log |
| 198 | whenever an accepted SMTP connection terminates without having issued a |
| 199 | MAIL command. |
| 200 | |
| 201 | 2. When an item in a dnslists list is followed by = and & and a list of IP |
| 202 | addresses, the behaviour was not clear when the lookup returned more than |
| 203 | one IP address. This has been solved by the addition of == and =& for "all" |
| 204 | rather than the default "any" matching. |
| 205 | |
| 206 | 3. Up till now, the only control over which cipher suites GnuTLS uses has been |
| 207 | for the cipher algorithms. New options have been added to allow some of the |
| 208 | other parameters to be varied. |
| 209 | |
| 210 | 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is |
| 211 | set, Exim compiles a runtime option called disable_fsync. |
| 212 | |
| 213 | 5. There is a new variable called $smtp_count_at_connection_start. |
| 214 | |
| 215 | 6. There's a new control called no_pipelining. |
| 216 | |
| 217 | 7. There are two new variables called $sending_ip_address and $sending_port. |
| 218 | These are set whenever an SMTP connection to another host has been set up. |
| 219 | |
| 220 | 8. The expansion of the helo_data option in the smtp transport now happens |
| 221 | after the connection to the server has been made. |
| 222 | |
| 223 | 9. There is a new expansion operator ${rfc2047d: that decodes strings that |
| 224 | are encoded as per RFC 2047. |
| 225 | |
| 226 | 10. There is a new log selector called "pid", which causes the current process |
| 227 | id to be added to every log line, in square brackets, immediately after the |
| 228 | time and date. |
| 229 | |
| 230 | 11. Exim has been modified so that it flushes SMTP output before implementing |
| 231 | a delay in an ACL. It also flushes the output before performing a callout, |
| 232 | as this can take a substantial time. These behaviours can be disabled by |
| 233 | obeying control = no_delay_flush or control = no_callout_flush, |
| 234 | respectively, at some earlier stage of the connection. |
| 235 | |
| 236 | 12. There are two new expansion conditions that iterate over a list. They are |
| 237 | called forany and forall. |
| 238 | |
| 239 | 13. There's a new global option called dsn_from that can be used to vary the |
| 240 | contents of From: lines in bounces and other automatically generated |
| 241 | messages ("delivery status notifications" - hence the name of the option). |
| 242 | |
| 243 | 14. The smtp transport has a new option called hosts_avoid_pipelining. |
| 244 | |
| 245 | 15. By default, exigrep does case-insensitive matches. There is now a -I option |
| 246 | that makes it case-sensitive. |
| 247 | |
| 248 | 16. A number of new features ("addresses", "map", "filter", and "reduce") have |
| 249 | been added to string expansions to make it easier to process lists of |
| 250 | items, typically addresses. |
| 251 | |
| 252 | 17. There's a new ACL modifier called "continue". It does nothing of itself, |
| 253 | and processing of the ACL always continues with the next condition or |
| 254 | modifier. It is provided so that the side effects of expanding its argument |
| 255 | can be used. |
| 256 | |
| 257 | 18. It is now possible to use newline and other control characters (those with |
| 258 | values less than 32, plus DEL) as separators in lists. |
| 259 | |
| 260 | 19. The exigrep utility now has a -v option, which inverts the matching |
| 261 | condition. |
| 262 | |
| 263 | 20. The host_find_failed option in the manualroute router can now be set to |
| 264 | "ignore". |
| 265 | |
| 266 | |
| 267 | Version 4.66 |
| 268 | ------------ |
| 269 | |
| 270 | No new features were added to 4.66. |
| 271 | |
| 272 | |
| 273 | Version 4.65 |
| 274 | ------------ |
| 275 | |
| 276 | No new features were added to 4.65. |
| 277 | |
| 278 | |
| 279 | Version 4.64 |
| 280 | ------------ |
| 281 | |
| 282 | 1. ACL variables can now be given arbitrary names, as long as they start with |
| 283 | "acl_c" or "acl_m" (for connection variables and message variables), are at |
| 284 | least six characters long, with the sixth character being either a digit or |
| 285 | an underscore. |
| 286 | |
| 287 | 2. There is a new ACL modifier called log_reject_target. It makes it possible |
| 288 | to specify which logs are used for messages about ACL rejections. |
| 289 | |
| 290 | 3. There is a new authenticator called "dovecot". This is an interface to the |
| 291 | authentication facility of the Dovecot POP/IMAP server, which can support a |
| 292 | number of authentication methods. |
| 293 | |
| 294 | 4. The variable $message_headers_raw provides a concatenation of all the |
| 295 | messages's headers without any decoding. This is in contrast to |
| 296 | $message_headers, which does RFC2047 decoding on the header contents. |
| 297 | |
| 298 | 5. In a DNS black list, if two domain names, comma-separated, are given, the |
| 299 | second is used first to do an initial check, making use of any IP value |
| 300 | restrictions that are set. If there is a match, the first domain is used, |
| 301 | without any IP value restrictions, to get the TXT record. |
| 302 | |
| 303 | 6. All authenticators now have a server_condition option. |
| 304 | |
| 305 | 7. There is a new command-line option called -Mset. It is useful only in |
| 306 | conjunction with -be (that is, when testing string expansions). It must be |
| 307 | followed by a message id; Exim loads the given message from its spool |
| 308 | before doing the expansions. |
| 309 | |
| 310 | 8. Another similar new command-line option is called -bem. It operates like |
| 311 | -be except that it must be followed by the name of a file that contains a |
| 312 | message. |
| 313 | |
| 314 | 9. When an address is delayed because of a 4xx response to a RCPT command, it |
| 315 | is now the combination of sender and recipient that is delayed in |
| 316 | subsequent queue runs until its retry time is reached. |
| 317 | |
| 318 | 10. Unary negation and the bitwise logical operators and, or, xor, not, and |
| 319 | shift, have been added to the eval: and eval10: expansion items. |
| 320 | |
| 321 | 11. The variables $interface_address and $interface_port have been renamed |
| 322 | as $received_ip_address and $received_port, to make it clear that they |
| 323 | relate to message reception rather than delivery. (The old names remain |
| 324 | available for compatibility.) |
| 325 | |
| 326 | 12. The "message" modifier can now be used on "accept" and "discard" acl verbs |
| 327 | to vary the message that is sent when an SMTP command is accepted. |
| 328 | |
| 329 | |
| 330 | Version 4.63 |
| 331 | ------------ |
| 332 | |
| 333 | 1. There is a new Boolean option called filter_prepend_home for the redirect |
| 334 | router. |
| 335 | |
| 336 | 2. There is a new acl, set by acl_not_smtp_start, which is run right at the |
| 337 | start of receiving a non-SMTP message, before any of the message has been |
| 338 | read. |
| 339 | |
| 340 | 3. When an SMTP error message is specified in a "message" modifier in an ACL, |
| 341 | or in a :fail: or :defer: message in a redirect router, Exim now checks the |
| 342 | start of the message for an SMTP error code. |
| 343 | |
| 344 | 4. There is a new parameter for LDAP lookups called "referrals", which takes |
| 345 | one of the settings "follow" (the default) or "nofollow". |
| 346 | |
| 347 | 5. Version 20070721.2 of exipick now included, offering these new options: |
| 348 | --reverse |
| 349 | After all other sorting options have bee processed, reverse order |
| 350 | before displaying messages (-R is synonym). |
| 351 | --random |
| 352 | Randomize order of matching messages before displaying. |
| 353 | --size |
| 354 | Instead of displaying the matching messages, display the sum |
| 355 | of their sizes. |
| 356 | --sort <variable>[,<variable>...] |
| 357 | Before displaying matching messages, sort the messages according to |
| 358 | each messages value for each variable. |
| 359 | --not |
| 360 | Negate the value for every test (returns inverse output from the |
| 361 | same criteria without --not). |
| 362 | |
| 363 | |
| 364 | Version 4.62 |
| 365 | ------------ |
| 366 | |
| 367 | 1. The ${readsocket expansion item now supports Internet domain sockets as well |
| 368 | as Unix domain sockets. If the first argument begins "inet:", it must be of |
| 369 | the form "inet:host:port". The port is mandatory; it may be a number or the |
| 370 | name of a TCP port in /etc/services. The host may be a name, or it may be an |
| 371 | IP address. An ip address may optionally be enclosed in square brackets. |
| 372 | This is best for IPv6 addresses. For example: |
| 373 | |
| 374 | ${readsocket{inet:[::1]:1234}{<request data>}... |
| 375 | |
| 376 | Only a single host name may be given, but if looking it up yield more than |
| 377 | one IP address, they are each tried in turn until a connection is made. Once |
| 378 | a connection has been made, the behaviour is as for ${readsocket with a Unix |
| 379 | domain socket. |
| 380 | |
| 381 | 2. If a redirect router sets up file or pipe deliveries for more than one |
| 382 | incoming address, and the relevant transport has batch_max set greater than |
| 383 | one, a batch delivery now occurs. |
| 384 | |
| 385 | 3. The appendfile transport has a new option called maildirfolder_create_regex. |
| 386 | Its value is a regular expression. For a maildir delivery, this is matched |
| 387 | against the maildir directory; if it matches, Exim ensures that a |
| 388 | maildirfolder file is created alongside the new, cur, and tmp directories. |
| 389 | |
| 390 | |
| 391 | Version 4.61 |
| 392 | ------------ |
| 393 | |
| 394 | The documentation is up-to-date for the 4.61 release. Major new features since |
| 395 | the 4.60 release are: |
| 396 | |
| 397 | . An option called disable_ipv6, to disable the use of IPv6 completely. |
| 398 | |
| 399 | . An increase in the number of ACL variables to 20 of each type. |
| 400 | |
| 401 | . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1, |
| 402 | $2, $3, (though those are still set) because the numeric variables get used |
| 403 | for other things in complicated expansions. |
| 404 | |
| 405 | . The default for rfc1413_query_timeout has been changed from 30s to 5s. |
| 406 | |
| 407 | . It is possible to use setclassresources() on some BSD OS to control the |
| 408 | resources used in pipe deliveries. |
| 409 | |
| 410 | . A new ACL modifier called add_header, which can be used with any verb. |
| 411 | |
| 412 | . More errors are detectable in retry rules. |
| 413 | |
| 414 | There are a number of other additions too. |
| 415 | |
| 416 | |
| 417 | Version 4.60 |
| 418 | ------------ |
| 419 | |
| 420 | The documentation is up-to-date for the 4.60 release. Major new features since |
| 421 | the 4.50 release are: |
| 422 | |
| 423 | . Support for SQLite. |
| 424 | |
| 425 | . Support for IGNOREQUOTA in LMTP. |
| 426 | |
| 427 | . Extensions to the "submission mode" features. |
| 428 | |
| 429 | . Support for Client SMTP Authorization (CSA). |
| 430 | |
| 431 | . Support for ratelimiting hosts and users. |
| 432 | |
| 433 | . New expansion items to help with the BATV "prvs" scheme. |
| 434 | |
| 435 | . A "match_ip" condition, that matches an IP address against a list. |
| 436 | |
| 437 | There are many more minor changes. |
| 438 | |
| 439 | **** |