X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/caba963291bb43dfc0e2cc0d0c6b3347aec09ce5..b0e63c7efdc2133c61545b051042d3617ecd2bbd:/doc/doc-docbook/spec.xfpt diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt index 2bdb2bbdf..dc8f5cc4d 100644 --- a/doc/doc-docbook/spec.xfpt +++ b/doc/doc-docbook/spec.xfpt @@ -22792,8 +22792,11 @@ If unset, or expanding to an empty string, no filtering is done. When the message is about to be written out, the command specified by &%transport_filter%& is started up in a separate, parallel process, and the entire message, including the header lines, is passed to it on its standard -input (this in fact is done from a third process, to avoid deadlock). The -command must be specified as an absolute path. +input (this in fact is done from a third process, to avoid deadlock). +The command must be specified as an absolute path. + +The process run by the command must use its standard input as the message +data to be transformed, and write the results on its standard output. The lines of the message that are written to the transport filter are terminated by newline (&"\n"&). The message is passed to the filter before any @@ -24828,7 +24831,7 @@ Exim, and each argument is separately expanded, as described in section No part of the resulting command may be tainted. -.option environment pipe string&!! unset +.option environment pipe "string list&!!" unset .cindex "&(pipe)& transport" "environment for command" .cindex "environment" "&(pipe)& transport" This option is used to add additional variables to the environment in which the @@ -25546,15 +25549,24 @@ load-balancer, matching the session stored in the client's cache. Exim can pull out a server name, if there is one, from the response to the client's SMTP EHLO command. -The default value of this option: +For normal STARTTLS use, the default value of this option: .code ${if and { {match {$host} {.outlook.com\$}} \ {match {$item} {\N^250-([\w.]+)\s\N}} \ } {$1}} .endd suffices for one known case. + During the expansion of this option the &$item$& variable will have the server's EHLO response. + +.new +For TLS-on-connect connections we do not have an EHLO +response to use. Because of this the default value of this option is +set to a static string for those cases, meaning that resumption will +always be attempted if permitted by the &%tls_resumption_hosts%& option. +.wen + The result of the option expansion is included in the key used to store and retrieve the TLS session, for session resumption. @@ -35323,9 +35335,10 @@ The arguments are as follows: (the -D file). The file is open for reading and writing, but updating it is not recommended. &*Warning*&: You must &'not'& close this file descriptor. -The descriptor is positioned at character 19 of the file, which is the first -character of the body itself, because the first 19 characters are the message -id followed by &`-D`& and a newline. If you rewind the file, you should use the +The descriptor is positioned at character 26 of the file, which is the first +character of the body itself, because the first 26 characters (19 characters +before Exim 4.97) are the message id followed by &`-D`& and a newline. +If you rewind the file, you should use the macro SPOOL_DATA_START_OFFSET to reset to the start of the data, just in case this changes in some future version. .next @@ -39084,7 +39097,7 @@ selection marked by asterisks: .irow &`tls_peerdn`&   "TLS peer DN on <= and => lines" .irow &`tls_resumption`&   "append * to cipher field" .irow &`tls_sni`&   "TLS SNI on <= lines" -.irow &`unknown_in_list`&   "DNS lookup failed in list match" +.irow &`unknown_in_list`&   "lookup failed in list match" .irow &`all`&   "&*all of the above*&" .endtable See also the &%slow_lookup_log%& main configuration option, @@ -39503,7 +39516,8 @@ added to the log line, preceded by SNI=. .next .cindex "log" "DNS failure in list" &%unknown_in_list%&: This setting causes a log entry to be written when the -result of a list match is failure because a DNS lookup failed. +result of a list match is failure because a DNS lookup failed, or because +a bad IP address was in the list. .endlist @@ -41698,7 +41712,7 @@ variables here. .option dkim_sign_headers smtp string&!! "see below" If set, this option must expand to a colon-separated list of header names. -Headers with these names, or the absence or such a header, will be included +Headers with these names, or the absence of such a header, will be included in the message signature. When unspecified, the header names listed in RFC4871 will be used, whether or not each header is present in the message. @@ -41733,8 +41747,9 @@ RFC 6376 lists these tags as RECOMMENDED. Verification of DKIM signatures in SMTP incoming email is done for all messages for which an ACL control &%dkim_disable_verify%& has not been set. + .cindex DKIM "selecting signature algorithms" -Individual classes of signature algorithm can be ignored by changing +Individual classes of DKIM signature algorithm can be ignored by changing the main options &%dkim_verify_hashes%& or &%dkim_verify_keytypes%&. The &%dkim_verify_minimal%& option can be set to cease verification processing for a message once the first passing signature is found. @@ -41747,7 +41762,7 @@ For most purposes the default option settings suffice and the remainder of this section can be ignored. The results of verification are made available to the -&%acl_smtp_dkim%& ACL, which can examine and modify them. +&%acl_smtp_dkim%& ACL, which (for complex needs) can examine and modify them. A missing ACL definition defaults to accept. By default, the ACL is called once for each syntactically(!) correct signature in the incoming message. @@ -41812,6 +41827,12 @@ an identity. This is one of the list items from the expanded main option &%dkim_verify_signers%& (see above). .vitem &%$dkim_verify_status%& +So long as a DKIM ACL is defined +(it need do no more than accept, which is the default), +after all the DKIM ACL runs have completed, the value becomes a +colon-separated list of the values after each run. +The value is maintained for the MIME, PRDR and DATA ACLs. + Within the DKIM ACL, a string describing the general status of the signature. One of .ilist @@ -41840,11 +41861,6 @@ hash-method or key-size: set dkim_verify_reason = hash too weak or key too short .endd -So long as a DKIM ACL is defined (it need do no more than accept), -after all the DKIM ACL runs have completed, the value becomes a -colon-separated list of the values after each run. -This is maintained for the mime, prdr and data ACLs. - .vitem &%$dkim_verify_reason%& A string giving a little bit more detail when &%$dkim_verify_status%& is either "fail" or "invalid". One of @@ -41969,13 +41985,15 @@ option. .endlist -In addition, two ACL conditions are provided, usable only in a DKIM ACL: +In addition, two ACL conditions are provided: .vlist .vitem &%dkim_signers%& ACL condition that checks a colon-separated list of domains or identities for a match against the domain or identity that the ACL is currently verifying -(reflected by &%$dkim_cur_signer%&). This is typically used to restrict an ACL +(reflected by &%$dkim_cur_signer%&). +This condition is only usable in a DKIM ACL. +This is typically used to restrict an ACL verb to a group of domains or identities. For example: .code @@ -41991,7 +42009,18 @@ for that check for empty &$h_DKIM-Signature:$& in the data ACL. .vitem &%dkim_status%& ACL condition that checks a colon-separated list of possible DKIM verification -results against the actual result of verification. This is typically used +results against the actual result of verification, +given by &$dkim_verify_status$& if that is non-empty or "none" if empty. +.new +This condition may be used in DKIM, MIME, PRDR and DATA ACLs. +.wen + +A basic verification might be: +.code +deny !dkim_status = pass:none:invalid +.endd + +A more complex use could be to restrict an ACL verb to a list of verification outcomes, for example: .code @@ -42004,6 +42033,12 @@ deny sender_domains = paypal.com:paypal.de The possible status keywords are: 'none','invalid','fail' and 'pass'. Please see the documentation of the &%$dkim_verify_status%& expansion variable above for more information of what they mean. + +The condition is true if the status +.new +(or any of the list of status values) +.wen +is any one of the supplied list. .endlist