| 1 | $Cambridge: exim/doc/doc-txt/NewStuff,v 1.97 2006/03/16 11:51:09 ph10 Exp $ |
| 2 | |
| 3 | New Features in Exim |
| 4 | -------------------- |
| 5 | |
| 6 | This file contains descriptions of new features that have been added to Exim, |
| 7 | but have not yet made it into the main manual (which is most conveniently |
| 8 | updated when there is a relatively large batch of changes). The doc/ChangeLog |
| 9 | file contains a listing of all changes, including bug fixes. |
| 10 | |
| 11 | Version 4.61 |
| 12 | ------------ |
| 13 | |
| 14 | PH/01 There is a new global option called disable_ipv6, which does exactly what |
| 15 | its name implies. If set true, even if the Exim binary has IPv6 support, |
| 16 | no IPv6 activities take place. AAAA records are never looked up for host |
| 17 | names given in manual routing data or elsewhere. AAAA records that are |
| 18 | received from the DNS as additional data for MX records are ignored. Any |
| 19 | IPv6 addresses that are listed in local_interfaces, manualroute route |
| 20 | data, etc. are also ignored. If IP literals are enabled, the ipliteral |
| 21 | router declines to handle IPv6 literal addresses. |
| 22 | |
| 23 | PH/02 There are now 20 of each type of ACL variable by default (instead of 10). |
| 24 | It is also possible to change the numbers by setting ACL_CVARS and/or |
| 25 | ACL_MVARS in Local/Makefile. Backward compatibility is maintained if you |
| 26 | upgrade to this release with existing messages containing ACL variable |
| 27 | settings on the queue. However, going in the other direction |
| 28 | (downgrading) will not be compatible; the values of ACL variables will be |
| 29 | lost. |
| 30 | |
| 31 | PH/03 If quota_warn_message contains a From: header, Exim now refrains from |
| 32 | adding the default one. Similarly, if it contains a Reply-To: header, the |
| 33 | errors_reply_to option, if set, is not used. |
| 34 | |
| 35 | PH/04 The variables $auth1, $auth2, $auth3 are now available in authenticators, |
| 36 | containing the same values as $1, $2, $3. The new variables are provided |
| 37 | because the numerical variables can be reset during string expansions |
| 38 | (for example, during a "match" operation) and so may lose the |
| 39 | authentication data. The preferred variables are now the new ones, with |
| 40 | the use of the numerical ones being deprecated, though the support will |
| 41 | not be removed, at least, not for a long time. |
| 42 | |
| 43 | PH/05 The "control=freeze" ACL modifier can now be followed by /no_tell. If |
| 44 | the global option freeze_tell is set, it is ignored for the current |
| 45 | message (that is, nobody is told about the freezing), provided all the |
| 46 | "control=freeze" modifiers that are obeyed in the current message have |
| 47 | the /no_tell option. |
| 48 | |
| 49 | PH/06 In both GnuTLS and OpenSSL, an expansion of tls_privatekey that results |
| 50 | in an empty string is now treated as unset. |
| 51 | |
| 52 | PH/07 There is a new log selector called sender_verify_fail, which is set by |
| 53 | default. If it is unset, the separate log line that gives details of a |
| 54 | sender verification failure is not written. Log lines for the rejection |
| 55 | of SMTP commands (e.g. RCPT) contain just "sender verify failed", so some |
| 56 | detail is lost. |
| 57 | |
| 58 | PH/08 The default for dns_check_names_pattern now allows slashes within names, |
| 59 | as there are now some PTR records that contain slashes. This check is |
| 60 | only to protect against broken name servers that fall over on strange |
| 61 | characters, so the fact that it applies to all lookups doesn't matter. |
| 62 | |
| 63 | PH/09 The default for rfc4131_query_timeout has been changed from 30s to 5s. |
| 64 | |
| 65 | PH/10 When compiled on FreeBSD, NetBSD, or BSD/OS, the pipe transport has a new |
| 66 | Boolean option called use_classresources, defaulting false. If it is set |
| 67 | true, the setclassresources() function is used to set resource limits |
| 68 | when a pipe transport is run to perform a delivery. The limits for the |
| 69 | uid under which the pipe is to run are obtained from the login class |
| 70 | database. |
| 71 | |
| 72 | PH/11 If retry_interval_max is set greater than 24 hours, it is quietly reset |
| 73 | to 24 hours. This avoids potential overflow problems when processing G |
| 74 | and H retry rules, and it seems reasonable to require a retry at least |
| 75 | once a day. |
| 76 | |
| 77 | PH/12 When the plaintext authenticator is running as a client, the server |
| 78 | challenges are now checked to ensure they are valid base64 strings. The |
| 79 | default action on failure is to abort the authentication. However, if |
| 80 | client_ignore_invalid_base64 is set true, invalid responses are ignored. |
| 81 | |
| 82 | PH/13 When the plaintext authenticator is running as a client, the challenges |
| 83 | from the server are placed in $auth1, $auth2, etc. as they are received. |
| 84 | Thus, the challege that is received in response to sending the first |
| 85 | string (with the AUTH command) can be used in the expansion of the second |
| 86 | string, and so on. Currently, up to 3 challenge strings are available in |
| 87 | this way. If an invalid base64 string is received when client_ignore_ |
| 88 | invalid_base64 is set, an empty string is put in the $auth<n> variable. |
| 89 | |
| 90 | PH/14 Messages created by the autoreply transport now contain a References: |
| 91 | header. This is constructed in accordance with rules that are described |
| 92 | in section 3.64 of RFC 2822, which states that replies should contain |
| 93 | such a header line, and section 3.14 of RFC 3834, which states that |
| 94 | automatic responses are not different in this respect. However, because |
| 95 | some mail processing software does not cope well with very long header |
| 96 | lines, no more than 12 message IDs are copied from the References: header |
| 97 | line in the incoming message. If there are more than 12, the first one |
| 98 | and then the final 11 are copied, before adding the message ID of the |
| 99 | incoming message. |
| 100 | |
| 101 | PH/15 The smtp transport has a new option called authenticated_sender_force. |
| 102 | When set true, it allows the authenticated_sender option's value to be |
| 103 | used, even if Exim has not authenticated as a client. |
| 104 | |
| 105 | PH/16 The expansion ${time_eval:<string>} converts an Exim time string such as |
| 106 | 2d4h1m into a number of seconds. |
| 107 | |
| 108 | PH/17 The ACL modifier control=allow_auth_unadvertised can be used to permit a |
| 109 | client host to use the SMTP AUTH command even when it has not been |
| 110 | advertised in response to EHLO. Furthermore, because there are apparently |
| 111 | some really broken clients that do this, Exim will even accept AUTH after |
| 112 | HELO when this control is set. It should only be used if you really need |
| 113 | it, and you should limit its use to those broken hosts that do not work |
| 114 | without it. For example: |
| 115 | |
| 116 | warn hosts = 192.168.34.25 |
| 117 | control = allow_auth_unadvertised |
| 118 | |
| 119 | This control is permitted only in the connection and HELO ACLs. |
| 120 | |
| 121 | PH/18 There is a new ACL modifier called "add_header" which does what its name |
| 122 | implies. It specifies one of more header lines that are to be added to an |
| 123 | incoming message, assuming, of course, that the message is ultimately |
| 124 | accepted. |
| 125 | |
| 126 | This modifier is permitted in the MAIL, RCPT, PREDATA, DATA, MIME, and |
| 127 | non-SMTP ACLs (in other words, those that are concerned with accepting a |
| 128 | message). Added header lines are accumulated during the MAIL, RCPT, and |
| 129 | PREDATA ACLs, with any duplicates being discarded. They are then added to |
| 130 | the message before processing the DATA and MIME ACLs, during which |
| 131 | further added header lines are accumulated, again with duplicates |
| 132 | discarded. Thus, it is possible to add two identical header lines to an |
| 133 | SMTP message, but only if one is added before DATA and one after. |
| 134 | |
| 135 | In the case of non-SMTP messages, new headers are accumulated during the |
| 136 | non-SMTP ACL, and added to the message at the end. |
| 137 | |
| 138 | The add_header modifier is available for use with all ACL verbs. In the |
| 139 | case of the WARN verb, add_header supersedes the use of "message" for |
| 140 | this purpose; for the other verbs, it provides a new facility. If both |
| 141 | add_header and "message" are present on a WARN verb, both are processed |
| 142 | according to their specifications. |
| 143 | |
| 144 | The add_header modifier acts immediately it is encountered during the |
| 145 | processing of an ACL. This is different to the (now-deprecated) use of |
| 146 | "message" on a WARN verb, where the action is taken only if all the |
| 147 | conditions are true. Notice the difference between these two cases on a |
| 148 | RCPT ACL: |
| 149 | |
| 150 | deny add_header = ADDED: some text |
| 151 | <some condition> |
| 152 | |
| 153 | deny <some condition> |
| 154 | add_header = ADDED: some text |
| 155 | |
| 156 | In the first case, the header is always added, whether or not the current |
| 157 | recipient is rejected. In the second case, the header is added only if |
| 158 | the recipient is rejected. |
| 159 | |
| 160 | If add_header appears more than once on an ACL statement, multiple |
| 161 | headers are added, provided that they have different content. (In the |
| 162 | case of WARN with "message", only the last value of "message" is used.) |
| 163 | |
| 164 | The facility for specifying where the new header is to be inserted, as |
| 165 | described for WARN with "message" in section 39.19 of the 4.60 manual, is |
| 166 | supported. |
| 167 | |
| 168 | PH/19 The following errors can now be detected in retry rules: |
| 169 | |
| 170 | mail_4xx This is like rcpt_4xx, but applies to MAIL commands |
| 171 | |
| 172 | data_4xx This is like rcpt_4xx, but applies to DATA commands and the |
| 173 | response code after the end of the data |
| 174 | |
| 175 | lost_connection This error occurs when the server unexpectedly closes |
| 176 | the SMTP connection. There may, of course, legitmate reasons |
| 177 | for this (host died, network died), but if it repeats a lot |
| 178 | for the same host, it indicates something odd. |
| 179 | |
| 180 | tls_required The server was required to use TLS (hosts_require_tls), |
| 181 | but either did not offer it, or responded with 4xx to |
| 182 | STARTTLS, or there was a problem setting up the TLS connection |
| 183 | |
| 184 | Note that a 5xx response to STARTTLS is a permanent error. |
| 185 | |
| 186 | PH/20 There are now two options for the exicyclog script: |
| 187 | |
| 188 | -k <days> specifies the number of old logs to keep, overriding the |
| 189 | default that is set when Exim is built. |
| 190 | |
| 191 | -l <path> specifies the log file path, in the same format as the |
| 192 | log_file_path option (e.g. /var/log/exim_%slog), again, |
| 193 | overriding the script's default - which is to find the setting |
| 194 | from Exim's configuration. |
| 195 | |
| 196 | |
| 197 | Version 4.60 |
| 198 | ------------ |
| 199 | |
| 200 | The documentation is up-to-date for the 4.60 release. Major new features since |
| 201 | the 4.50 release are: |
| 202 | |
| 203 | . Support for SQLite. |
| 204 | |
| 205 | . Support for IGNOREQUOTA in LMTP. |
| 206 | |
| 207 | . Extensions to the "submission mode" features. |
| 208 | |
| 209 | . Support for Client SMTP Authorization (CSA). |
| 210 | |
| 211 | . Support for ratelimiting hosts and users. |
| 212 | |
| 213 | . New expansion items to help with the BATV "prvs" scheme. |
| 214 | |
| 215 | . A "match_ip" condition, that matches an IP address against a list. |
| 216 | |
| 217 | There are many more minor changes. |
| 218 | |
| 219 | **** |