X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/48d6f3b6c68a33a4ff11650f9f0de858cb5fc256..04f8907ae05b4ac5af26d4a6080b9d787c27fa7f:/doc/doc-docbook/spec.xfpt?ds=inline diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt index 6ee615145..202c27659 100644 --- a/doc/doc-docbook/spec.xfpt +++ b/doc/doc-docbook/spec.xfpt @@ -1805,6 +1805,11 @@ suited to Exim's usage model. Yet another DBM library, called &'tdb'&, is available from &url(https://sourceforge.net/projects/tdb/files/). It has its own interface, and also operates on a single file. +.next +.new +It is possible to use sqlite3 (&url(https://www.sqlite.org/index.html)) +for the DBM library. +.wen .endlist .cindex "USE_DB" @@ -1816,8 +1821,9 @@ USE_DB in an appropriate configuration file (typically .code USE_DB=yes .endd -Similarly, for gdbm you set USE_GDBM, and for tdb you set USE_TDB. An -error is diagnosed if you set more than one of these. +Similarly, for gdbm you set USE_GDBM, for tdb you set USE_TDB, +and for sqlite3 you set USE_SQLITE. +An error is diagnosed if you set more than one of these. You can set USE_NDBM if needed to override an operating system default. At the lowest level, the build-time configuration sets none of these options, @@ -1833,6 +1839,7 @@ in one of these lines: .code DBMLIB = -ldb DBMLIB = -ltdb +DBMLIB = -lsqlite3 DBMLIB = -lgdbm -lgdbm_compat .endd The last of those was for a Linux having GDBM provide emulated NDBM facilities. @@ -3101,7 +3108,7 @@ options, as appropriate. The &%-bnq%& option (see below) provides a way of suppressing this for special cases. Policy checks on the contents of local messages can be enforced by means of -the non-SMTP ACL. See chapter &<>& for details. +the non-SMTP ACL. See section &<>& for details. .cindex "return code" "for &%-bm%&" The return code is zero if the message is successfully accepted. Otherwise, the @@ -3377,7 +3384,7 @@ dots doubled), terminated by a line containing just a single dot. An error is provoked if the terminating dot is missing. A further message may then follow. As for other local message submissions, the contents of incoming batch SMTP -messages can be checked using the non-SMTP ACL (see chapter &<>&). +messages can be checked using the non-SMTP ACL (see section &<>&). Unqualified addresses are automatically qualified using &%qualify_domain%& and &%qualify_recipient%&, as appropriate, unless the &%-bnq%& option is used. @@ -4715,7 +4722,7 @@ all selected messages, not just the first; frozen messages are included when The &%-R%& option makes it straightforward to initiate delivery of all messages to a given domain after a host has been down for some time. When the SMTP -command ETRN is accepted by its ACL (see chapter &<>&), its default +command ETRN is accepted by its ACL (see section &<>&), its default effect is to run Exim with the &%-R%& option, but it can be configured to run an arbitrary command instead. @@ -11585,6 +11592,19 @@ literal question mark). .cindex "&%utf8_localpart_from_alabel%& expansion item" These convert EAI mail name components between UTF-8 and a-label forms. For information on internationalisation support see &<>&. + + +.new +.vitem &*${xtextd:*&<&'string'&>&*}*& +.cindex "text forcing in strings" +.cindex "string" "xtext decoding" +.cindex "xtext" +.cindex "&%xtextd%& expansion item" +This performs xtext decoding of the string (per RFC 3461 section 4). +.wen + + + .endlist @@ -14836,6 +14856,7 @@ listed in more than one group. .row &%acl_smtp_rcpt%& "ACL for RCPT" .row &%acl_smtp_starttls%& "ACL for STARTTLS" .row &%acl_smtp_vrfy%& "ACL for VRFY" +.row &%acl_smtp_wellknown%& "ACL for WELLKNOWN" .row &%av_scanner%& "specify virus scanner" .row &%check_rfc2047_length%& "check length of RFC 2047 &""encoded &&& words""&" @@ -15002,6 +15023,7 @@ See also the &'Policy controls'& section above. .row &%prdr_enable%& "advertise PRDR to all hosts" .row &%smtputf8_advertise_hosts%& "advertise SMTPUTF8 to these hosts" .row &%tls_advertise_hosts%& "advertise TLS to these hosts" +.row &%wellknown_advertise_hosts%& "advertise WELLKNOWN to these hosts" .endtable @@ -15125,7 +15147,7 @@ log_selector = +8bitmime .cindex "&ACL;" "for non-SMTP messages" .cindex "non-SMTP messages" "ACLs for" This option defines the ACL that is run when a non-SMTP message has been -read and is on the point of being accepted. See chapter &<>& for +read and is on the point of being accepted. See section &<>& for further details. .option acl_not_smtp_mime main string&!! unset @@ -15137,24 +15159,26 @@ SMTP messages. .cindex "&ACL;" "at start of non-SMTP message" .cindex "non-SMTP messages" "ACLs for" This option defines the ACL that is run before Exim starts reading a -non-SMTP message. See chapter &<>& for further details. +non-SMTP message. See section &<>& for further details. .option acl_smtp_auth main string&!! unset .cindex "&ACL;" "setting up for SMTP commands" .cindex "AUTH" "ACL for" This option defines the ACL that is run when an SMTP AUTH command is -received. See chapter &<>& for further details. +received. +See chapter &<>& for general information on ACLs, and chapter +&<>& for details of authentication. .option acl_smtp_connect main string&!! unset .cindex "&ACL;" "on SMTP connection" This option defines the ACL that is run when an SMTP connection is received. -See chapter &<>& for further details. +See section &<>& for further details. .option acl_smtp_data main string&!! unset .cindex "DATA" "ACL for" This option defines the ACL that is run after an SMTP DATA command has been processed and the message itself has been received, but before the final -acknowledgment is sent. See chapter &<>& for further details. +acknowledgment is sent. See section &<>& for further details. .option acl_smtp_data_prdr main string&!! accept .cindex "PRDR" "ACL for" @@ -15165,7 +15189,7 @@ This option defines the ACL that, if the PRDR feature has been negotiated, is run for each recipient after an SMTP DATA command has been processed and the message itself has been received, but before the -acknowledgment is sent. See chapter &<>& for further details. +acknowledgment is sent. See section &<>& for further details. .option acl_smtp_dkim main string&!! unset .cindex DKIM "ACL for" @@ -15188,7 +15212,7 @@ received. See chapter &<>& for further details. .cindex "EHLO" "ACL for" .cindex "HELO" "ACL for" This option defines the ACL that is run when an SMTP EHLO or HELO -command is received. See chapter &<>& for further details. +command is received. See section &<>& for further details. .option acl_smtp_mail main string&!! unset @@ -15199,7 +15223,8 @@ received. See chapter &<>& for further details. .option acl_smtp_mailauth main string&!! unset .cindex "AUTH" "on MAIL command" This option defines the ACL that is run when there is an AUTH parameter on -a MAIL command. See chapter &<>& for details of ACLs, and chapter +a MAIL command. +See chapter &<>& for general information on ACLs, and chapter &<>& for details of authentication. .option acl_smtp_mime main string&!! unset @@ -15212,7 +15237,7 @@ section &<>& for details. .cindex "not-QUIT, ACL for" This option defines the ACL that is run when an SMTP session ends without a QUIT command being received. -See chapter &<>& for further details. +See section &<>& for further details. .option acl_smtp_predata main string&!! unset This option defines the ACL that is run when an SMTP DATA command is @@ -15227,7 +15252,7 @@ received. See chapter &<>& for further details. .option acl_smtp_rcpt main string&!! unset .cindex "RCPT" "ACL for" This option defines the ACL that is run when an SMTP RCPT command is -received. See chapter &<>& for further details. +received. See section &<>& for further details. .option acl_smtp_starttls main string&!! unset .cindex "STARTTLS, ACL for" @@ -15239,6 +15264,13 @@ received. See chapter &<>& for further details. This option defines the ACL that is run when an SMTP VRFY command is received. See chapter &<>& for further details. +.new +.option acl_smtp_wellknown main string&!! unset +.cindex "WELLKNOWN, ACL for" +This option defines the ACL that is run when an SMTP WELLKNOWN command is +received. See section &<>& for further details. +.wen + .option add_environment main "string list" empty .cindex "environment" "set values" This option adds individual environment variables that the @@ -16593,7 +16625,7 @@ If permitted, Exim as a servier will advertise in the EHLO response the limit for RCPT commands set by the &%recipients_max%& option (if it is set) and the limit for MAIL commands set by the &%smtp_accept_max_per_connection%& option. -,wen +.wen .option local_from_check main boolean true .cindex "&'Sender:'& header line" "disabling addition of" @@ -18910,6 +18942,14 @@ absolute and untainted. See also &%bounce_message_file%&. +.new +.option wellknown_advertise_hosts main boolean unset +.cindex WELLKNOWN advertisement +.cindex "ESMTP extensions" WELLKNOWN +This option enables the advertising of the SMTP WELLKNOWN extension. +See also the &%acl_smtp_wellknown%& ACL (&<>&). +.wen + .option write_rejectlog main boolean true .cindex "reject log" "disabling" If this option is set false, Exim no longer writes anything to the reject log. @@ -30642,6 +30682,7 @@ options in the main part of the configuration. These options are: .cindex "RCPT" "ACL for" .cindex "STARTTLS, ACL for" .cindex "VRFY" "ACL for" +.cindex "WELLKNOWN" "ACL for" .cindex "SMTP" "connection, ACL for" .cindex "non-SMTP messages" "ACLs for" .cindex "MIME content scanning" "ACL for" @@ -30668,6 +30709,7 @@ options in the main part of the configuration. These options are: .irow &%acl_smtp_rcpt%& "ACL for RCPT" .irow &%acl_smtp_starttls%& "ACL for STARTTLS" .irow &%acl_smtp_vrfy%& "ACL for VRFY" +.irow &%acl_smtp_wellknown%& "ACL for WELLKNOWN" .endtable For example, if you set @@ -30683,7 +30725,7 @@ trying to deliver the message. It is therefore recommended that you do as much testing as possible at RCPT time. -.subsection "The non-SMTP ACLs" SECID190 +.subsection "The non-SMTP ACLs" SECnonSMTP .cindex "non-SMTP messages" "ACLs for" The non-SMTP ACLs apply to all non-interactive incoming messages, that is, they apply to batched SMTP as well as to non-SMTP messages. (Batched SMTP is not @@ -30717,7 +30759,7 @@ kind of rejection is treated as permanent, because there is no way of sending a temporary error for these kinds of message. -.subsection "The SMTP connect ACL" SECID191 +.subsection "The SMTP connect ACL" SECconnectACL .cindex "SMTP" "connection, ACL for" .oindex &%smtp_banner%& The ACL test specified by &%acl_smtp_connect%& happens at the start of an SMTP @@ -30732,7 +30774,7 @@ is accepted; if the ACL does not accept then the TCP connection is dropped witho any TLS startup attempt and without any SMTP response being transmitted. -.subsection "The EHLO/HELO ACL" SECID192 +.subsection "The EHLO/HELO ACL" SECheloACL .cindex "EHLO" "ACL for" .cindex "HELO" "ACL for" The ACL test specified by &%acl_smtp_helo%& happens when the client issues an @@ -30753,7 +30795,7 @@ affect the EHLO options that are listed on the second and subsequent lines of an EHLO response. -.subsection "The DATA ACLs" SECID193 +.subsection "The DATA ACLs" SECdataACLS .cindex "DATA" "ACLs for" Two ACLs are associated with the DATA command, because it is two-stage command, with two responses being sent to the client. @@ -30850,6 +30892,62 @@ This ACL is evaluated after &%acl_smtp_dkim%& but before &%acl_smtp_data%&. If the ACL is not defined, processing completes as if the feature was not requested by the client. +.new +.subsection "The SMTP WELLKNOWN ACL" SECTWELLKNOWNACL +.cindex "WELLKNOWN" "ACL for" +.oindex "&%acl_smtp_wellknown%&" +The &%acl_smtp_wellknown%& ACL is available only when Exim is compiled +with WELLKNOWN support enabled. + +The ACL determines the response to an SMTP WELLKNOWN command, using the normal +accept/defer/deny verbs for the response code, +and a new &"control=wellknown"& modifier. +This modifier takes a single option, separated by a '/' +character, which must be the name of a file containing the response +cleartext. The modifier is expanded before use in the usual way before +it is used. The configuration is responsible for picking a suitable file +to return and, most importantly, not returning any unexpected file. +The argument for the SMTP verb will be available in the &$smtp_command_argument$& +variable and can be used for building the file path. +If the file path given in the modifier is empty or inacessible, the control will +fail. + +For example: +.code + check_wellknown: + accept control = wellknown/\ + ${lookup {${xtextd:$smtp_command_argument}} \ + dsearch,key=path,filter=file,ret=full \ + {$spooldir/wellknown.d}} +.endd +File content will be encoded in &"xtext"& form, and line-wrapping +for line-length limitation will be done before transmission. +A response summary line will be prepended, with the (pre-encoding) file size. + +The above example uses the expansion operator ${xtextd:} +which is needed to decode the xtext-encoded key from the SMTP verb. + +Under the util directory there is a "mailtest" utility which can be used +to test/retrieve WELLKNOWN items. Syntax is +.code + mailtest -h host.example.com -w security.txt +.endd + +WELLKNOWN is a ESMTP extension providing access to extended +information about the server. It is modelled on the webserver +facilities documented in RFC 8615 and can be used for a security.txt +file and could be used for ACME handshaking (RFC 8555). + +Exim will advertise WELLKNOWN support in the EHLO response +.oindex &%wellknown_advertise_hosts%& +(conditional on a new option &%wellknown_advertise_hosts%&) +and service WELLKNOWN smtp verbs having a single parameter +giving a key for an item of "site-wide metadata". +The verb and key are separated by whitespace, +and the key is xtext-encoded (per RFC 3461 section 4). +.wen + + .subsection "The QUIT ACL" SECTQUITACL .cindex "QUIT, ACL for" The ACL for the SMTP QUIT command is anomalous, in that the outcome of the ACL @@ -31020,12 +31118,15 @@ For &%acl_not_smtp%&, &%acl_smtp_auth%&, &%acl_smtp_connect%&, &%acl_smtp_mime%&, &%acl_smtp_predata%&, and &%acl_smtp_starttls%&, the action when the ACL is not defined is &"accept"&. -For the others (&%acl_smtp_etrn%&, &%acl_smtp_expn%&, &%acl_smtp_rcpt%&, and -&%acl_smtp_vrfy%&), the action when the ACL is not defined is &"deny"&. -This means that &%acl_smtp_rcpt%& must be defined in order to receive any -messages over an SMTP connection. For an example, see the ACL in the default -configuration file. - +For the others (&%acl_smtp_etrn%&, &%acl_smtp_expn%&, &%acl_smtp_rcpt%&, +&%acl_smtp_vrfy%& +.new +and &%acl_smtp_wellknown%&), +.wen +the action when the ACL +is not defined is &"deny"&. This means that &%acl_smtp_rcpt%& must be +defined in order to receive any messages over an SMTP connection. +For an example, see the ACL in the default configuration file. @@ -32130,6 +32231,13 @@ that are being submitted at the same time using &%-bs%& or &%-bS%&. This control enables conversion of UTF-8 in message envelope addresses to a-label form. For details see section &<>&. + +.new +.vitem &*control&~=&~wellknown*& +This control sets up a response data file for a WELLKNOWN SMTP command. +It may only be used in an ACL servicing that command. +For details see section &<>&. +.wen .endlist vlist