1This document contains detailed information about incompatibilities that might 2be encountered when upgrading from one release of Exim to another. The 3information is in reverse order of release numbers. Mostly these are relatively 4small points, and the configuration file is normally upwards compatible, but 5there have been two big upheavals... 6 7 8************************************************************************** 9* There was a big reworking of the way mail routing works for release * 10* 4.00. Previously used "directors" were abolished, and all routing is * 11* now done by routers. Policy controls for incoming mail are now done by * 12* Access Control Lists instead of separate options. All this means that * 13* pre-4.00 configuration files have to be massively converted. If you * 14* are coming from a 3.xx release, please read the document in the file * 15* doc/Exim4.upgrade, and allow some time to complete the upgrade. * 16* * 17* There was a big reworking of the way domain/host/net/address lists are * 18* handled at release 3.00. If you are coming from a pre-3.00 release, it * 19* might be easier to start again from a default configuration. Otherwise * 20* you need to read doc/Exim3.upgrade and do a double conversion of your * 21* configuration file. * 22************************************************************************** 23 24 25The rest of this document contains information about changes in 4.xx releases 26that might affect a running system. 27 28 29Exim version 4.95 30----------------- 31 32Various length limits have been applied to Exim's parsing of its command-line. 33These are all set to be at least as long as any valid input, so we do not believe 34that any real use-cases have been affected by this. 35 36The names of various drivers (authenticators, routers, transports, ...) have 37always been limited to 64 characters, but before this release the names were 38silently truncated, inviting problems. Now the length limit should be enforced. 39If this affects you, then please rename to use shorter names. 40 41The default maximum number of recipients of a single email has changed from 42"unlimited" (ie: as much as CPU and memory will allow, until something breaks 43badly) to 50,000. You can raise or lower this as you see fit, but we strongly 44caution against using zero/unlimited. 45 46 47Exim version 4.94 48----------------- 49 50Some Transports now refuse to use tainted data in constructing their delivery 51location; this WILL BREAK configurations which are not updated accordingly. 52In particular: any Transport use of $local_part which has been relying upon 53check_local_user far away in the Router to make it safe, should be updated to 54replace $local_part with $local_part_data. 55 56Attempting to remove, in router or transport, a header name that ends with 57an asterisk (which is a standards-legal name) will now result in all headers 58named starting with the string before the asterisk being removed. We recommend 59staying away from such names, if they are private ones (and in case of future 60enhancements, alao header names that look like REs). 61 62 63Exim version 4.93 64----------------- 65 66For a detailed list of changes that might affect Exim's operation with 67an unchanged configuration, please see the doc/ChangeLog file. 68 69Build: 70 71 * SUPPORT_DMARC replaces EXPERIMENTAL_DMARC 72 73 * DISABLE_TLS replaces SUPPORT_TLS 74 75 * Bump the version for the local_scan API. 76 77Runtime: 78 79 * smtp transport option hosts_try_fastopen defaults to "*". 80 81 * DNSSec is requested (not required) for all queries. (This seemes to 82 ask for trouble if your resolver is a systemd-resolved.) 83 84 * Generic router option retry_use_local_part defaults to "true" under specific 85 pre-conditions. 86 87 * Introduce a tainting mechanism for values read from untrusted sources. 88 89 * Use longer file names for temporary spool files (this avoids 90 name conflicts with spool on a shared file system). 91 92 * Use dsn_from main config option (was ignored previously). 93 94 95Exim version 4.92 96----------------- 97 98 * Exim used to manually follow CNAME chains, to a limited depth. In this 99 day-and-age we expect the resolver to be doing this for us, so the loop 100 is limited to one retry unless the (new) config option dns_cname_loops 101 is changed. 102 103Exim version 4.91 104----------------- 105 106 * DANE and SPF have been promoted from Experimental to Supported status, thus 107 the options to enable them in Local/Makefile have been renamed. 108 See current src/EDITME for full details, including changes in dependencies, 109 but loosely: replace EXPERIMENTAL_SPF with SUPPORT_SPF and replace 110 EXPERIMENTAL_DANE with SUPPORT_DANE. 111 112 * Ancient ClamAV stream support, long deprecated by ClamAV, has been removed; 113 if you were building with WITH_OLD_CLAMAV_STREAM enabled then your problems 114 have marginally increased. 115 116 * A number of logging changes; if relying upon the previous DKIM additional 117 log-line, explicit log_selector configuration is needed to keep it. 118 119 * Other incompatible changes in EXPERIMENTAL_* features, read NewStuff and 120 ChangeLog carefully if relying upon an experimental feature such as DMARC. 121 Note that this includes changes to SPF as it was promoted into Supported. 122 123 124Exim version 4.89 125----------------- 126 127 * SMTP CHUNKING in Exim 4.88 did not ensure that received mails had a final 128 newline; attempts to deliver such messages onwards to non-chunking hosts 129 would probably hang, as Exim does not insert the newline before a ".". 130 In 4.89, the newline is added upon receipt. For already-received messages 131 in your queue, try util/chunking_fixqueue_finalnewlines.pl 132 to walk the queue, fixing any affected messages. Note that because a 133 delivery attempt will be hanging, attempts to lock the messages for fixing 134 them will stall; stopping all queue-runners temporarily is recommended. 135 136 * OpenSSL: oldest supported release series is now 1.0.2, which is the oldest 137 supported by the OpenSSL project. If you can build Exim with an older 138 release series, congratulations. If you can't, then upgrade. 139 The file doc/openssl.txt contains instructions for installing a current 140 OpenSSL outside the system library paths and building Exim to use it. 141 142 * FreeBSD: we now always use the system iconv in libc, as all versions of 143 FreeBSD supported by the FreeBSD project provide this functionality. 144 145 146Exim version 4.88 147----------------- 148 149 * The "demime" ACL condition, deprecated for the past 10 years, has 150 now been removed. 151 152 * Old GnuTLS configuration options "gnutls_require_kx", "gnutls_require_mac", 153 and "gnutls_require_protocols" have now been removed. (Inoperative from 154 4.80, per below; logging warnings since 4.83, again per below). 155 156 157Exim version 4.83 158----------------- 159 160 * SPF condition results renamed "permerror" and "temperror". The old 161 names are still accepted for back-compatibility, for this release. 162 163 * TLS details are now logged on rejects, subject to log selectors. 164 165 * Items in headers_remove lists must now have any embedded list-separators 166 doubled. 167 168 * Attempted use of the deprecated options "gnutls_require_kx" et. al. 169 now result in logged warning. 170 171 172Exim version 4.82 173----------------- 174 175 * New option gnutls_allow_auto_pkcs11 defaults false; if you have GnuTLS 2.12.0 176 or later and do want PKCS11 modules to be autoloaded, then set this option. 177 178 * A per-transport wait-<name> database is no longer updated if the transport 179 sets "connection_max_messages" to 1, as it can not be used and causes 180 unnecessary serialisation and load. External tools tracking the state of 181 Exim by the hints databases may need modification to take this into account. 182 183 * The av_scanner option can now accept multiple clamd TCP targets, all other 184 setting limitations remain. 185 186 187Exim version 4.80 188----------------- 189 190 * BEWARE backwards-incompatible changes in SSL libraries, thus the version 191 bump. See points below for details. 192 Also an LDAP data returned format change. 193 194 * The value of $tls_peerdn is now print-escaped when written to the spool file 195 in a -tls_peerdn line, and unescaped when read back in. We received reports 196 of values with embedded newlines, which caused spool file corruption. 197 198 If you have a corrupt spool file and you wish to recover the contents after 199 upgrading, then lock the message, replace the new-lines that should be part 200 of the -tls_peerdn line with the two-character sequence \n and then unlock 201 the message. No tool has been provided as we believe this is a rare 202 occurrence. 203 204 * For OpenSSL, SSLv2 is now disabled by default. (GnuTLS does not support 205 SSLv2). RFC 6176 prohibits SSLv2 and some informal surveys suggest no 206 actual usage. You can re-enable with the "openssl_options" Exim option, 207 in the main configuration section. Note that supporting SSLv2 exposes 208 you to ciphersuite downgrade attacks. 209 210 * With OpenSSL 1.0.1+, Exim now supports TLS 1.1 and TLS 1.2. If built 211 against 1.0.1a then you will get a warning message and the 212 "openssl_options" value will not parse "no_tlsv1_1": the value changes 213 incompatibly between 1.0.1a and 1.0.1b, because the value chosen for 1.0.1a 214 is infelicitous. We advise avoiding 1.0.1a. 215 216 "openssl_options" gains "no_tlsv1_1", "no_tlsv1_2" and "no_compression". 217 218 COMPATIBILITY WARNING: The default value of "openssl_options" is no longer 219 "+dont_insert_empty_fragments". We default to "+no_sslv2". 220 That old default was grandfathered in from before openssl_options became a 221 configuration option. 222 Empty fragments are inserted by default through TLS1.0, to partially defend 223 against certain attacks; TLS1.1+ change the protocol so that this is not 224 needed. The DIEF SSL option was required for some old releases of mail 225 clients which did not gracefully handle the empty fragments, and was 226 initially set in Exim release 4.31 (see ChangeLog, item 37). 227 228 If you still have affected mail-clients, and you see SSL protocol failures 229 with this release of Exim, set: 230 openssl_options = +dont_insert_empty_fragments 231 in the main section of your Exim configuration file. You're trading off 232 security for compatibility. Exim is now defaulting to higher security and 233 rewarding more modern clients. 234 235 If the option tls_dhparams is set and the parameters loaded from the file 236 have a bit-count greater than the new option tls_dh_max_bits, then the file 237 will now be ignored. If this affects you, raise the tls_dh_max_bits limit. 238 We suspect that most folks are using dated defaults and will not be affected. 239 240 * Ldap lookups returning multi-valued attributes now separate the attributes 241 with only a comma, not a comma-space sequence. Also, an actual comma within 242 a returned attribute is doubled. This makes it possible to parse the 243 attribute as a comma-separated list. Note the distinction from multiple 244 attributes being returned, where each one is a name=value pair. 245 246 If you are currently splitting the results from LDAP upon a comma, then you 247 should check carefully to see if adjustments are needed. 248 249 This change lets cautious folks distinguish "comma used as separator for 250 joining values" from "comma inside the data". 251 252 * accept_8bitmime now defaults on, which is not RFC compliant but is better 253 suited to today's Internet. See http://cr.yp.to/smtp/8bitmime.html for a 254 sane rationale. Those who wish to be strictly RFC compliant, or know that 255 they need to talk to servers that are not 8-bit-clean, now need to take 256 explicit configuration action to default this option off. This is not a 257 new option, you can safely force it off before upgrading, to decouple 258 configuration changes from the binary upgrade while remaining RFC compliant. 259 260 * The GnuTLS support has been mostly rewritten, to use APIs which don't cause 261 deprecation warnings in GnuTLS 2.12.x. As part of this, these three options 262 are no longer supported: 263 264 gnutls_require_kx 265 gnutls_require_mac 266 gnutls_require_protocols 267 268 Their functionality is entirely subsumed into tls_require_ciphers. In turn, 269 tls_require_ciphers is no longer an Exim list and is not parsed by Exim, but 270 is instead given to gnutls_priority_init(3), which expects a priority string; 271 this behaviour is much closer to the OpenSSL behaviour. See: 272 273 http://www.gnutls.org/manual/html_node/Priority-Strings.html 274 275 for fuller documentation of the strings parsed. The three gnutls_require_* 276 options are still parsed by Exim and, for this release, silently ignored. 277 A future release will add warnings, before a later still release removes 278 parsing entirely and the presence of the options will be a configuration 279 error. 280 281 Note that by default, GnuTLS will not accept RSA-MD5 signatures in chains. 282 A tls_require_ciphers value of NORMAL:%VERIFY_ALLOW_SIGN_RSA_MD5 may 283 re-enable support, but this is not supported by the Exim maintainers. 284 Our test suite no longer includes MD5-based certificates. 285 286 This rewrite means that Exim will continue to build against GnuTLS in the 287 future, brings Exim closer to other GnuTLS applications and lets us add 288 support for SNI and other features more readily. We regret that it wasn't 289 feasible to retain the three dropped options. 290 291 * If built with TLS support, then Exim will now validate the value of 292 the main section tls_require_ciphers option at start-up. Before, this 293 would cause a STARTTLS 4xx failure, now it causes a failure to start. 294 Running with a broken configuration which causes failures that may only 295 be left in the logs has been traded off for something more visible. This 296 change makes an existing problem more prominent, but we do not believe 297 anyone would deliberately be running with an invalid tls_require_ciphers 298 option. 299 300 This also means that library linkage issues caused by conflicts of some 301 kind might take out the main daemon, not just the delivery or receiving 302 process. Conceivably some folks might prefer to continue delivering 303 mail plaintext when their binary is broken in this way, if there is a 304 server that is a candidate to receive such mails that does not advertise 305 STARTTLS. Note that Exim is typically a setuid root binary and given 306 broken linkage problems that cause segfaults, we feel it is safer to 307 fail completely. (The check is not done as root, to ensure that problems 308 here are not made worse by the check). 309 310 * The "tls_dhparam" option has been updated, so that it can now specify a 311 path or an identifier for a standard DH prime from one of a few RFCs. 312 The default for OpenSSL is no longer to not use DH but instead to use 313 one of these standard primes. The default for GnuTLS is no longer to use 314 a file in the spool directory, but to use that same standard prime. 315 The option is now used by GnuTLS too. If it points to a path, then 316 GnuTLS will use that path, instead of a file in the spool directory; 317 GnuTLS will attempt to create it if it does not exist. 318 319 To preserve the previous behaviour of generating files in the spool 320 directory, set "tls_dhparam = historic". Since prior releases of Exim 321 ignored tls_dhparam when using GnuTLS, this can safely be done before 322 the upgrade. 323 324 325 326Exim version 4.77 327----------------- 328 329 * GnuTLS will now attempt to use TLS 1.2 and TLS 1.1 before TLS 1.0 and SSL3, 330 if supported by your GnuTLS library. Use the existing 331 "gnutls_require_protocols" option to downgrade this if that will be a 332 problem. Prior to this release, supported values were "TLS1" and "SSL3", 333 so you should be able to update configuration prior to update. 334 335 [nb: gnutls_require_protocols removed in Exim 4.80, instead use 336 tls_require_ciphers to provide a priority string; see notes above] 337 338 * The match_<type>{string1}{string2} expansion conditions no longer subject 339 string2 to string expansion, unless Exim was built with the new 340 "EXPAND_LISTMATCH_RHS" option. Too many people have inadvertently created 341 insecure configurations that way. If you need the functionality and turn on 342 that build option, please let the developers know, and know why, so we can 343 try to provide a safer mechanism for you. 344 345 The match{}{} expansion condition (for regular expressions) is NOT affected. 346 For match_<type>{s1}{s2}, all list functionality is unchanged. The only 347 change is that a '$' appearing in s2 will not trigger expansion, but instead 348 will be treated as a literal $ sign; the effect is very similar to having 349 wrapped s2 with \N...\N. If s2 contains a named list and the list definition 350 uses $expansions then those _will_ be processed as normal. It is only the 351 point at which s2 is read where expansion is inhibited. 352 353 If you are trying to test if two email addresses are equal, use eqi{s1}{s2}. 354 If you are testing if the address in s1 occurs in the list of items given 355 in s2, either use the new inlisti{s1}{s2} condition (added in 4.77) or use 356 the pre-existing forany{s2}{eqi{$item}{s1}} condition. 357 358 359Exim version 4.74 360----------------- 361 362 * The integrated support for dynamically loadable lookup modules has an ABI 363 change from the modules supported by some OS vendors through an unofficial 364 patch. Don't try to mix & match. 365 366 * Some parts of the build system are now beginning to assume that the host 367 environment is POSIX. If you're building on a system where POSIX tools are 368 not the default, you might have an easier time if you switch to the POSIX 369 tools. Feel free to report non-POSIX issues as a request for a feature 370 enhancement, but if the POSIX variants are available then the fix will 371 probably just involve some coercion. See the README instructions for 372 building on such hosts. 373 374 375Exim version 4.73 376----------------- 377 378 * The Exim run-time user can no longer be root; this was always 379 strongly discouraged, but is now prohibited both at build and 380 run-time. If you need Exim to run routinely as root, you'll need to 381 patch the source and accept the risk. Here be dragons. 382 383 * Exim will no longer accept a configuration file owned by the Exim 384 run-time user, unless that account is explicitly the value in 385 CONFIGURE_OWNER, which we discourage. Exim now checks to ensure that 386 files are not writeable by other accounts. 387 388 * The ALT_CONFIG_ROOT_ONLY build option is no longer optional and is forced 389 on; the Exim user can, by default, no longer use -C/-D and retain privilege. 390 Two new build options mitigate this. 391 392 * TRUSTED_CONFIG_LIST defines a file containing a whitelist of config 393 files that are trusted to be selected by the Exim user; one per line. 394 This is the recommended approach going forward. 395 396 * WHITELIST_D_MACROS defines a colon-separated list of macro names which 397 the Exim run-time user may safely pass without dropping privileges. 398 Because changes to this involve a recompile, this is not the recommended 399 approach but may ease transition. The values of the macros, when 400 overridden, are constrained to match this regex: ^[A-Za-z0-9_/.-]*$ 401 402 * The system_filter_user option now defaults to the Exim run-time user, 403 rather than root. You can still set it explicitly to root and this 404 can be done with prior versions too, letting you roll versions 405 without needing to change this configuration option. 406 407 * ClamAV must be at least version 0.95 unless WITH_OLD_CLAMAV_STREAM is 408 defined at build time. 409 410 411Exim version 4.70 412----------------- 413 4141. Experimental Yahoo! Domainkeys support has been dropped in this release. 415It has been superseded by a native implementation of its successor DKIM. 416 4172. Up to version 4.69, Exim came with an embedded version of the PCRE library. 418As of 4.70, this is no longer the case. To compile Exim, you will need PCRE 419installed. Most OS distributions have ready-made library and development 420packages. 421 422 423Exim version 4.68 424----------------- 425 4261. The internal implementation of the database keys that are used for ACL 427ratelimiting has been tidied up. This means that an update to 4.68 might cause 428Exim to "forget" previous rates that it had calculated, and reset them to zero. 429 430 431Exim version 4.64 432----------------- 433 4341. Callouts were setting the name used for EHLO/HELO from $smtp_active_ 435hostname. This is wrong, because it relates to the incoming message (and 436probably the interface on which it is arriving) and not to the outgoing 437callout (which could be using a different interface). This has been 438changed to use the value of the helo_data option from the smtp transport 439instead - this is what is used when a message is actually being sent. If 440there is no remote transport (possible with a router that sets up host 441addresses), $smtp_active_hostname is used. This change is mentioned here in 442case somebody is relying on the use of $smtp_active_hostname. 443 4442. A bug has been fixed that might just possibly be something that is relied on 445in some configurations. In expansion items such as ${if >{xxx}{yyy}...} an 446empty string (that is {}) was being interpreted as if it was {0} and therefore 447treated as the number zero. From release 4.64, such strings cause an error 448because a decimal number, possibly followed by K or M, is required (as has 449always been documented). 450 4513. There has been a change to the GnuTLS support (ChangeLog/PH/20) to improve 452Exim's performance. Unfortunately, this has the side effect of being slightly 453non-upwards compatible for versions 4.50 and earlier. If you are upgrading from 454one of these earlier versions and you use GnuTLS, you must remove the file 455called gnutls-params in Exim's spool directory. If you don't do this, you will 456see this error: 457 458 TLS error on connection from ... (DH params import): Base64 decoding error. 459 460Removing the file causes Exim to recompute the relevant encryption parameters 461and cache them in the new format that was introduced for release 4.51 (May 4622005). If you are upgrading from release 4.51 or later, there should be no 463problem. 464 465 466Exim version 4.63 467----------------- 468 469When an SMTP error message is specified in a "message" modifier in an ACL, or 470in a :fail: or :defer: message in a redirect router, Exim now checks the start 471of the message for an SMTP error code. This consists of three digits followed 472by a space, optionally followed by an extended code of the form n.n.n, also 473followed by a space. If this is the case and the very first digit is the same 474as the default error code, the code from the message is used instead. If the 475very first digit is incorrect, a panic error is logged, and the default code is 476used. This is an incompatible change, but it is not expected to affect many (if 477any) configurations. It is possible to suppress the use of the supplied code in 478a redirect router by setting the smtp_error_code option false. In this case, 479any SMTP code is quietly ignored. 480 481 482Exim version 4.61 483----------------- 484 4851. The default number of ACL variables of each type has been increased to 20, 486and it's possible to compile Exim with more. You can safely upgrade to this 487release if you already have messages on the queue with saved ACL variable 488values. However, if you downgrade from this release with messages on the queue, 489any saved ACL values they may have will be lost. 490 4912. The default value for rfc1413_query_timeout has been changed from 30s to 5s. 492 493 494Exim version 4.54 495----------------- 496 497There was a problem with 4.52/TF/02 in that a "name=" option on control= 498submission terminated at the next slash, thereby not allowing for slashes in 499the name. This has been changed so that "name=" takes the rest of the string as 500its data. It must therefore be the last option. 501 502 503Version 4.53 504------------ 505 506If you are using the experimental Domain Keys support, you must upgrade to 507at least libdomainkeys 0.67 in order to run this release of Exim. 508 509 510Version 4.51 511------------ 512 5131. The format in which GnuTLS parameters are cached (in the file gnutls-params 514in the spool directory) has been changed. The new format can also be generated 515externally, so it is now possible to update the values from outside Exim. This 516has been implemented in an upwards, BUT NOT downwards, compatible manner. 517Upgrading should be seamless: when Exim finds that it cannot understand an 518existing cache file, it generates new parameters and writes them to the cache 519in the new format. If, however, you downgrade from 4.51 to a previous release, 520you MUST delete the gnutls-params file in the spool directory, because the 521older Exim will not recognize the new format. 522 5232. When doing a callout as part of verifying an address, Exim was not paying 524attention to any local part prefix or suffix that was matched by the router 525that accepted the address. It now behaves in the same way as it does for 526delivery: the affixes are removed from the local part unless 527rcpt_include_affixes is set on the transport. If you have a configuration that 528uses prefixes or suffixes on addresses that could be used for callouts, and you 529want the affixes to be retained, you must make sure that rcpt_include_affixes 530is set on the transport. 531 5323. Bounce and delay warning messages no longer contain details of delivery 533errors, except for explicit messages (e.g. generated by :fail:) and SMTP 534responses from remote hosts. 535 536 537Version 4.50 538------------ 539 540The exicyclog script has been updated to use three-digit numbers in rotated log 541files if the maximum number to keep is greater than 99. If you are already 542keeping more than 99, there will be an incompatible change when you upgrade. 543You will probably want to rename your old log files to the new form before 544running the new exicyclog. 545 546 547Version 4.42 548------------ 549 550RFC 3848 specifies standard names for the "with" phrase in Received: header 551lines when AUTH and/or TLS are in use. This is the "received protocol" 552field. Exim used to use "asmtp" for authenticated SMTP, without any 553indication (in the protocol name) for TLS use. Now it follows the RFC and 554uses "esmtpa" if the connection is authenticated, "esmtps" if it is 555encrypted, and "esmtpsa" if it is both encrypted and authenticated. These names 556appear in log lines as well as in Received: header lines. 557 558 559Version 4.34 560------------ 561 562Change 4.31/2 gave problems to data ACLs and local_scan() functions that 563expected to see a Received: header. I have changed to yet another scheme. The 564Received: header is now generated after the body is received, but before the 565ACL or local_scan() is called. After they have run, the timestamp in the 566Received: header is updated. 567 568Thus, change (a) of 4.31/2 has been reversed, but change (b) is still true, 569which is lucky, since I decided it was a bug fix. 570 571 572Version 4.33 573------------ 574 575If an expansion in a condition on a "warn" statement fails because a lookup 576defers, the "warn" statement is abandoned, and the next ACL statement is 577processed. Previously this caused the whole ACL to be aborted. 578 579 580Version 4.32 581------------ 582 583Change 4.31/2 has been reversed, as it proved contentious. Recipient callout 584verification now uses <> in the MAIL command by default, as it did before. A 585new callout option, "use_sender", has been added to request the other 586behaviour. 587 588 589Version 4.31 590------------ 591 5921. If you compile Exim to use GnuTLS, it now requires the use of release 1.0.0 593 or greater. The interface to the obsolete 0.8.x releases is no longer 594 supported. There is one externally visible change: the format for the 595 display of Distinguished Names now uses commas as a separator rather than a 596 slash. This is to comply with RFC 2253. 597 5982. When a message is received, the Received: header line is now generated when 599 reception is complete, instead of at the start of reception. For messages 600 that take a long time to come in, this changes the meaning of the timestamp. 601 There are several side-effects of this change: 602 603 (a) If a message is rejected by a DATA or non-SMTP ACL, or by local_scan(), 604 the logged header lines no longer include the local Received: line, 605 because it has not yet been created. If the message is a non-SMTP one, 606 and the error is processed by sending a message to the sender, the copy 607 of the original message that is returned does not have an added 608 Received: line. 609 610 (b) When a filter file is tested using -bf, no additional Received: header 611 is added to the test message. After some thought, I decided that this 612 is a bug fix. 613 614 The contents of $received_for are not affected by this change. This 615 variable still contains the single recipient of a message, copied after 616 addresses have been rewritten, but before local_scan() is run. 617 6182. Recipient callout verification, like sender verification, was using <> in 619 the MAIL FROM command. This isn't really the right thing, since the actual 620 sender may affect whether the remote host accepts the recipient or not. I 621 have changed it to use the actual sender in the callout; this means that 622 the cache record is now keyed on a recipient/sender pair, not just the 623 recipient address. There doesn't seem to be a real danger of callout loops, 624 since a callout by the remote host to check the sender would use <>. 625 626 627Version 4.30 628------------ 629 6301. I have abolished timeout_DNS as an error that can be detected in retry 631 rules, because it has never worked. Despite the fact that it has been 632 documented since at least release 1.62, there was no code to support it. 633 If you have used it in your retry rules, you will now get a warning message 634 to the log and panic log. It is now treated as plain "timeout". 635 6362. After discussion on the mailing list, Exim no longer adds From:, Date:, or 637 Message-Id: header lines to messages that do not originate locally, that is, 638 messages that have an associated sending host address. 639 6403. When looking up a host name from an IP address, Exim now tries the DNS 641 first, and only if that fails does it use gethostbyaddr() (or equivalent). 642 This change was made because on some OS, not all the names are given for 643 addresses with multiple PTR records via the gethostbyaddr() interface. The 644 order of lookup can be changed by setting host_lookup_order. 645 646 647Version 4.23 648------------ 649 6501. The new FIXED_NEVER_USERS build-time option creates a list of "never users" 651 that cannot be overridden. The default in the distributed EDITME is "root". 652 If for some reason you were (against advice) running deliveries as root, you 653 will have to ensure that FIXED_NEVER_USERS is not set in your 654 Local/Makefile. 655 6562. The ${quote: operator now quotes an empty string, which it did not before. 657 6583. Version 4.23 saves the contents of the ACL variables with the message, so 659 that they can be used later. If one of these variables contains a newline, 660 there will be a newline character in the spool that will not be interpreted 661 correctly by a previous version of Exim. (Exim ignores keyed spool file 662 items that it doesn't understand - precisely for this kind of problem - but 663 it expects them all to be on one line.) 664 665 So the bottom line is: if you have newlines in your ACL variables, you 666 cannot retreat from 4.23. 667 668 669Version 4.21 670------------ 671 6721. The idea of the "warn" ACL verb is that it adds a header or writes to the 673 log only when "message" or "log_message" are set. However, if one of the 674 conditions was an address verification, or a call to a nested ACL, the 675 messages generated by the underlying test were being passed through. This 676 no longer happens. The underlying message is available in $acl_verify_ 677 message for both "message" and "log_message" expansions, so it can be 678 passed through if needed. 679 6802. The way that the $h_ (and $header_) expansions work has been changed by the 681 addition of RFC 2047 decoding. See the main documentation (the NewStuff file 682 until release 4.30, then the manual) for full details. Briefly, there are 683 now three forms: 684 685 $rh_xxx: and $rheader_xxx: give the original content of the header 686 line(s), with no processing at all. 687 688 $bh_xxx: and $bheader_xxx: remove leading and trailing white space, and 689 then decode base64 or quoted-printable "words" within the header text, 690 but do not do charset translation. 691 692 $h_xxx: and $header_xxx: attempt to translate the $bh_ string to a 693 standard character set. 694 695 If you have previously been using $h_ expansions to access the raw 696 characters, you should change to $rh_ instead. 697 6983. When Exim creates an RFC 2047 encoded word in a header line, it labels it 699 with the default character set from the headers_charset option instead of 700 always using iso-8859-1. 701 7024. If TMPDIR is defined in Local/Makefile (default in src/EDITME is 703 TMPDIR="/tmp"), Exim checks for the presence of an environment variable 704 called TMPDIR, and if it finds it is different, it changes its value. 705 7065. Following a discussion on the list, the rules by which Exim recognises line 707 endings on incoming messages have been changed. The -dropcr and drop_cr 708 options are now no-ops, retained only for backwards compatibility. The 709 following line terminators are recognized: LF CRLF CR. However, special 710 processing applies to CR: 711 712 (i) The sequence CR . CR does *not* terminate an incoming SMTP message, 713 nor a local message in the state where . is a terminator. 714 715 (ii) If a bare CR is encountered in a header line, an extra space is added 716 after the line terminator so as not to end the header. The reasoning 717 behind this is that bare CRs in header lines are most likely either 718 to be mistakes, or people trying to play silly games. 719 7206. The code for using daemon_smtp_port, local_interfaces, and the -oX options 721 has been reorganized. It is supposed to be backwards compatible, but it is 722 mentioned here just in case I've screwed up. 723 724 725 726Version 4.20 727------------ 728 7291. I have tidied and re-organized the code that uses alarm() for imposing time 730 limits on various things. It shouldn't affect anything, but if you notice 731 processes getting stuck, it may be that I've broken something. 732 7332. The "arguments" log selector now also logs the current working directory 734 when Exim is called. 735 7363. An incompatible change has been made to the appendfile transport. This 737 affects the case when it is used for file deliveries that are set up by 738 .forward and filter files. Previously, any settings of the "file" or 739 "directory" options were ignored. It is hoped that, like the address_file 740 transport in the default configuration, these options were never in fact set 741 on such transports, because they were of no use. 742 743 Now, if either of these options is set, it is used. The path that is passed 744 by the router is in $address_file (this is not new), so it can be used as 745 part of a longer path, or modified in any other way that expansion permits. 746 747 If neither "file" nor "directory" is set, the behaviour is unchanged. 748 7494. Related to the above: in a filter, if a "save" command specifies a non- 750 absolute path, the value of $home/ is pre-pended. This no longer happens if 751 $home is unset or is set to an empty string. 752 7535. Multiple file deliveries from a filter or .forward file can never be 754 batched; the value of batch_max on the transport is ignored for file 755 deliveries. I'm assuming that nobody ever actually set batch_max on the 756 address_file transport - it would have had odd effects previously. 757 7586. DESTDIR is the more common variable that ROOT for use when installing 759 software under a different root filing system. The Exim install script now 760 recognizes DESTDIR first; if it is not set, ROOT is used. 761 7627. If DESTDIR is set when installing Exim, it no longer prepends its value to 763 the path of the system aliases file that appears in the default 764 configuration (when a default configuration is installed). If an aliases 765 file is actually created, its name *does* use the prefix. 766 767 768Version 4.14 769------------ 770 7711. The default for the maximum number of unknown SMTP commands that Exim will 772accept before dropping a connection has been reduced from 5 to 3. However, you 773can now change the value by setting smtp_max_unknown_commands. 774 7752. The ${quote: operator has been changed so that it turns newline and carriage 776return characters into \n and \r, respectively. 777 7783. The file names used for maildir messages now include the microsecond time 779fraction as well as the time in seconds, to cope with systems where the process 780id can be re-used within the same second. The format is now 781 782 <time>.H<microsec>P<pid>.<host> 783 784This should be a compatible change, but is noted here just in case. 785 7864. The rules for creating message ids have changed, to cope with systems where 787the process id can be re-used within the same second. The format, however, is 788unchanged, so this should not cause any problems, except as noted in the next 789item. 790 7915. The maximum value for localhost_number has been reduced from 255 to 16, in 792order to implement the new message id rules. For operating systems that have 793case-insensitive file systems (Cygwin and Darwin), the limit is 10. 794 7956. verify = header_syntax was allowing unqualified addresses in all cases. Now 796it allows them only for locally generated messages and from hosts that match 797sender_unqualified_hosts or recipient_unqualified_hosts, respectively. 798 7997. For reasons lost in the mists of time, when a pipe transport was run, the 800environment variable MESSAGE_ID was set to the message ID preceded by 'E' (the 801form used in Message-ID: header lines). The 'E' has been removed. 802 803 804Version 4.11 805------------ 806 8071. The handling of lines in the configuration file has changed. Previously, 808macro expansion was applied to logical lines, after continuations had been 809joined on. This meant that it could not be used in .include lines, which are 810handled as physical rather than logical lines. Macro expansion is now done on 811physical lines rather than logical lines. This means there are two 812incompatibilities: 813 814 (a) A macro that expands to # to turn a line into a comment now applies only 815 to the physical line where it appears. Previously, it would have caused 816 any following continuations also to be ignored. 817 818 (b) A macro name can no longer be split over the boundary between a line and 819 its continuation. Actually, this is more of a bug fix. :-) 820 8212. The -D command line option must now all be within one command line item. 822This makes it possible to use -D to set a macro to the empty string by commands 823such as 824 825 exim -DABC ... 826 exim -DABC= ... 827 828Previously, these items would have moved on to the next item on the command 829line. To include spaces in a macro definition item, quotes must be used, in 830which case you can also have spaces after -D and surrounding the equals. For 831example: 832 833 exim '-D ABC = something' ... 834 8353. The way that addresses that redirect to themselves are handled has been 836changed, in order to fix an obscure bug. This should not cause any problems 837except in the case of wanting to go back from a 4.11 (or later) release to an 838earlier release. If there are undelivered messages on the spool that contain 839addresses which redirect to themselves, and the redirected addresses have 840already been delivered, you might get a duplicate delivery if you revert to an 841earlier Exim. 842 8434. The default way of looking up IP addresses for hosts in the manualroute and 844queryprogram routers has been changed. If "byname" or "bydns" is explicitly 845specified, there is no change, but if no method is specified, Exim now behaves 846as follows: 847 848 First, a DNS lookup is done. If this yields anything other than 849 HOST_NOT_FOUND, that result is used. Otherwise, Exim goes on to try a call to 850 getipnodebyname() (or gethostbyname() on older systems) and the result of the 851 lookup is the result of that call. 852 853This change has been made because it has been discovered that on some systems, 854if a DNS lookup called via getipnodebyname() times out, HOST_NOT_FOUND is 855returned instead of TRY_AGAIN. Thus, it is safest to try a DNS lookup directly 856first, and only if that gives a definite "no such host" to try the local 857function. 858 8595. In fixing the minor security problem with pid_file_path, I have removed some 860backwards-compatible (undocumented) code which was present to ease conversion 861from Exim 3. In Exim 4, pid_file_path is a literal; in Exim 3 it was allowed to 862contain "%s", which was replaced by the port number for daemons listening on 863non-standard ports. In Exim 4, such daemons do not write a pid file. The 864backwards compatibility feature was to replace "%s" by nothing if it occurred 865in an Exim 4 setting of pid_file_path. The bug was in this code. I have solved 866the problem by removing the backwards compatibility feature. Thus, if you still 867have "%s" somewhere in a setting of pid_file_path, you should remove it. 868 8696. There has been an extension to lsearch files. The keys in these files may 870now be quoted in order to allow for whitespace and colons in them. This means 871that if you were previously using keys that began with a doublequote, you will 872now have to wrap them with extra quotes and escape the internal quotes. The 873possibility that anybody is actually doing this seems extremely remote, but it 874is documented just in case. 875 876 877Version 4.10 878------------ 879 880The build-time parameter EXIWHAT_KILL_ARG has been renamed EXIWHAT_KILL_SIGNAL 881to better reflect its function. The OS-specific files have been updated. Only 882if you have explicitly set this in your Makefile (highly unlikely) do you need 883to change anything. 884 885**** 886