Add hosts_verify_avoid_tls option to smtp transport.

[exim.git] / doc / doc-docbook / spec.xfpt

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 9637b5194188538ae1397cb9746947db5eac3f96..85843843189956eae65b2a36e8da6c51a50e2300 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -2678,6 +2678,15 @@ no arguments.
 This option is an alias for &%-bV%& and causes version information to be
 displayed.
 
 This option is an alias for &%-bV%& and causes version information to be
 displayed.
 

+.new
+.vitem &%-Ac%& &&&
+       &%-Am%&
+.oindex "&%-Ac%&"
+.oindex "&%-Am%&"
+These options are used by Sendmail for selecting configuration files and are
+ignored by Exim.
+.wen
+

 .vitem &%-B%&<&'type'&>
 .oindex "&%-B%&"
 .cindex "8-bit characters"
 .vitem &%-B%&<&'type'&>
 .oindex "&%-B%&"
 .cindex "8-bit characters"


@@ -2937,6 +2946,8 @@ use the &'exim_dbmbuild'& utility, or some other means, to rebuild alias files
 if this is required. If the &%bi_command%& option is not set, calling Exim with
 &%-bi%& is a no-op.
 
 if this is required. If the &%bi_command%& option is not set, calling Exim with
 &%-bi%& is a no-op.
 

+.new
+. // Keep :help first, then the rest in alphabetical order

 .vitem &%-bI:help%&
 .oindex "&%-bI:help%&"
 .cindex "querying exim information"
 .vitem &%-bI:help%&
 .oindex "&%-bI:help%&"
 .cindex "querying exim information"


@@ -2946,6 +2957,12 @@ consumption.  This one is not.  The &%-bI:help%& option asks Exim for a
 synopsis of supported options beginning &`-bI:`&.  Use of any of these
 options shall cause Exim to exit after producing the requested output.
 
 synopsis of supported options beginning &`-bI:`&.  Use of any of these
 options shall cause Exim to exit after producing the requested output.
 

+.vitem &%-bI:dscp%&
+.oindex "&%-bI:dscp%&"
+.cindex "DSCP" "values"
+This option causes Exim to emit an alphabetically sorted list of all
+recognised DSCP names.
+

 .vitem &%-bI:sieve%&
 .oindex "&%-bI:sieve%&"
 .cindex "Sieve filter" "capabilities"
 .vitem &%-bI:sieve%&
 .oindex "&%-bI:sieve%&"
 .cindex "Sieve filter" "capabilities"


@@ -2955,6 +2972,7 @@ useful for ManageSieve (RFC 5804) implementations, in providing that protocol's
 &`SIEVE`& capability response line.  As the precise list may depend upon
 compile-time build options, which this option will adapt to, this is the only
 way to guarantee a correct response.
 &`SIEVE`& capability response line.  As the precise list may depend upon
 compile-time build options, which this option will adapt to, this is the only
 way to guarantee a correct response.

+.wen

 
 .vitem &%-bm%&
 .oindex "&%-bm%&"
 
 .vitem &%-bm%&
 .oindex "&%-bm%&"


@@ -3069,6 +3087,12 @@ configuration file is output.
 If a list of configuration files was supplied, the value that is output here
 is the name of the file that was actually used.
 
 If a list of configuration files was supplied, the value that is output here
 is the name of the file that was actually used.
 

+.new
+.cindex "options" "hiding name of"
+If the &%-n%& flag is given, then for most modes of &%-bP%& operation the
+name will not be output.
+.wen
+

 .cindex "daemon" "process id (pid)"
 .cindex "pid (process id)" "of daemon"
 If &%log_file_path%& or &%pid_file_path%& are given, the names of the
 .cindex "daemon" "process id (pid)"
 .cindex "pid (process id)" "of daemon"
 If &%log_file_path%& or &%pid_file_path%& are given, the names of the


@@ -3671,8 +3695,19 @@ if &%-f%& is also present, it overrides &"From&~"&.
 
 .vitem &%-G%&
 .oindex "&%-G%&"
 
 .vitem &%-G%&
 .oindex "&%-G%&"

-.cindex "Sendmail compatibility" "&%-G%& option ignored"
-This is a Sendmail option which is ignored by Exim.
+.cindex "submission fixups, suppressing (command-line)"
+.new
+This option is equivalent to an ACL applying:
+.code
+control = suppress_local_fixups
+.endd
+for every message received.  Note that Sendmail will complain about such
+bad formatting, where Exim silently just does not fix it up.  This may change
+in future.
+
+As this affects audit information, the caller must be a trusted user to use
+this option.
+.wen

 
 .vitem &%-h%&&~<&'number'&>
 .oindex "&%-h%&"
 
 .vitem &%-h%&&~<&'number'&>
 .oindex "&%-h%&"


@@ -3690,6 +3725,19 @@ line by itself should not terminate an incoming, non-SMTP message. I can find
 no documentation for this option in Solaris 2.4 Sendmail, but the &'mailx'&
 command in Solaris 2.4 uses it. See also &%-ti%&.
 
 no documentation for this option in Solaris 2.4 Sendmail, but the &'mailx'&
 command in Solaris 2.4 uses it. See also &%-ti%&.
 

+.new
+.vitem &%-L%&&~<&'tag'&>
+.oindex "&%-L%&"
+.cindex "syslog" "process name; set with flag"
+This option is equivalent to setting &%syslog_processname%& in the config
+file and setting &%log_file_path%& to &`syslog`&.
+Its use is restricted to administrators.  The configuration file has to be
+read and parsed, to determine access rights, before this is set and takes
+effect, so early configuration file errors will not honour this flag.
+
+The tag should not be longer than 32 characters.
+.wen
+

 .vitem &%-M%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
 .oindex "&%-M%&"
 .cindex "forcing delivery"
 .vitem &%-M%&&~<&'message&~id'&>&~<&'message&~id'&>&~...
 .oindex "&%-M%&"
 .cindex "forcing delivery"


@@ -3930,9 +3978,9 @@ for that message.
 
 .vitem &%-n%&
 .oindex "&%-n%&"
 
 .vitem &%-n%&
 .oindex "&%-n%&"

-.cindex "Sendmail compatibility" "&%-n%& option ignored"
-This option is interpreted by Sendmail to mean &"no aliasing"&. It is ignored
-by Exim.
+This option is interpreted by Sendmail to mean &"no aliasing"&.
+For normal modes of operation, it is ignored by Exim.
+When combined with &%-bP%& it suppresses the name of an option from being output.

 
 .vitem &%-O%&&~<&'data'&>
 .oindex "&%-O%&"
 
 .vitem &%-O%&&~<&'data'&>
 .oindex "&%-O%&"


@@ -4551,6 +4599,13 @@ AIX uses &%-x%& for a private purpose (&"mail from a local mail program has
 National Language Support extended characters in the body of the mail item"&).
 It sets &%-x%& when calling the MTA from its &%mail%& command. Exim ignores
 this option.
 National Language Support extended characters in the body of the mail item"&).
 It sets &%-x%& when calling the MTA from its &%mail%& command. Exim ignores
 this option.

+
+.new
+.vitem &%-X%&&~<&'logfile'&>
+.oindex "&%-X%&"
+This option is interpreted by Sendmail to cause debug information to be sent
+to the named file.  It is ignored by Exim.
+.wen

 .endlist
 
 .ecindex IIDclo1
 .endlist
 
 .ecindex IIDclo1


@@ -11679,6 +11734,31 @@ driver that successfully authenticated the client from which the message was
 received. It is empty if there was no successful authentication. See also
 &$authenticated_id$&.
 
 received. It is empty if there was no successful authentication. See also
 &$authenticated_id$&.
 

+.new
+.vitem &$sender_host_dnssec$&
+.vindex "&$sender_host_dnssec$&"
+If &$sender_host_name$& has been populated (by reference, &%hosts_lookup%& or
+otherwise) then this boolean will have been set true if, and only if, the
+resolver library states that the reverse DNS was authenticated data.  At all
+other times, this variable is false.
+
+It is likely that you will need to coerce DNSSEC support on in the resolver
+library, by setting:
+.code
+dns_use_dnssec = 1
+.endd
+
+Exim does not perform DNSSEC validation itself, instead leaving that to a
+validating resolver (eg, unbound, or bind with suitable configuration).
+
+Exim does not (currently) check to see if the forward DNS was also secured
+with DNSSEC, only the reverse DNS.
+
+If you have changed &%host_lookup_order%& so that &`bydns`& is not the first
+mechanism in the list, then this variable will be false.
+.wen
+
+

 .vitem &$sender_host_name$&
 .vindex "&$sender_host_name$&"
 When a message is received from a remote host, this variable contains the
 .vitem &$sender_host_name$&
 .vindex "&$sender_host_name$&"
 When a message is received from a remote host, this variable contains the


@@ -12828,6 +12908,9 @@ See also the &'Policy controls'& section above.
 .row &%dns_ipv4_lookup%&             "only v4 lookup for these domains"
 .row &%dns_retrans%&                 "parameter for resolver"
 .row &%dns_retry%&                   "parameter for resolver"
 .row &%dns_ipv4_lookup%&             "only v4 lookup for these domains"
 .row &%dns_retrans%&                 "parameter for resolver"
 .row &%dns_retry%&                   "parameter for resolver"

+.new
+.row &%dns_use_dnssec%&              "parameter for resolver"
+.wen

 .row &%dns_use_edns0%&               "parameter for resolver"
 .row &%hold_domains%&                "hold delivery for these domains"
 .row &%local_interfaces%&            "for routing checks"
 .row &%dns_use_edns0%&               "parameter for resolver"
 .row &%hold_domains%&                "hold delivery for these domains"
 .row &%local_interfaces%&            "for routing checks"


@@ -13468,6 +13551,18 @@ to set in them.
 See &%dns_retrans%& above.
 
 
 See &%dns_retrans%& above.
 
 

+.new
+.option dns_use_dnssec main integer -1
+.cindex "DNS" "resolver options"
+.cindex "DNS" "DNSSEC"
+If this option is set to a non-negative number then Exim will initialise the
+DNS resolver library to either use or not use DNSSEC, overriding the system
+default. A value of 0 coerces DNSSEC off, a value of 1 coerces DNSSEC on.
+
+If the resolver library does not support DNSSEC then this option has no effect.
+.wen
+
+

 .option dns_use_edns0 main integer -1
 .cindex "DNS" "resolver options"
 .cindex "DNS" "EDNS0"
 .option dns_use_edns0 main integer -1
 .cindex "DNS" "resolver options"
 .cindex "DNS" "EDNS0"


@@ -18362,6 +18457,18 @@ quote just the command. An item such as
 .endd
 is interpreted as a pipe with a rather strange command name, and no arguments.
 
 .endd
 is interpreted as a pipe with a rather strange command name, and no arguments.
 

+.new
+Note that the above example assumes that the text comes from a lookup source
+of some sort, so that the quotes are part of the data.  If composing a
+redirect router with a &%data%& option directly specifying this command, the
+quotes will be used by the configuration parser to define the extent of one
+string, but will not be passed down into the redirect router itself.  There
+are two main approaches to get around this: escape quotes to be part of the
+data itself, or avoid using this mechanism and instead create a custom
+transport with the &%command%& option set and reference that transport from
+an &%accept%& router.
+.wen
+

 .next
 .cindex "file" "in redirection list"
 .cindex "address redirection" "to file"
 .next
 .cindex "file" "in redirection list"
 .cindex "address redirection" "to file"


@@ -22046,6 +22153,22 @@ See the &%search_parents%& option in chapter &<<CHAPdnslookup>>& for more
 details.
 
 
 details.
 
 

+.new
+.option dscp smtp string&!! unset
+.cindex "DCSP" "outbound"
+This option causes the DSCP value associated with a socket to be set to one
+of a number of fixed strings or to numeric value.
+The &%-bI:dscp%& option may be used to ask Exim which names it knows of.
+Common values include &`throughput`&, &`mincost`&, and on newer systems
+&`ef`&, &`af41`&, etc.  Numeric values may be in the range 0 to 0x3F.
+
+The outbound packets from Exim will be marked with this value in the header
+(for IPv4, the TOS field; for IPv6, the TCLASS field); there is no guarantee
+that these values will have any effect, not be stripped by networking
+equipment, or do much of anything without cooperation with your Network
+Engineer and those of all network operators between the source and destination.
+.wen
+

 
 .option fallback_hosts smtp "string list" unset
 .cindex "fallback" "hosts specified on transport"
 
 .option fallback_hosts smtp "string list" unset
 .cindex "fallback" "hosts specified on transport"


@@ -22179,6 +22302,13 @@ that matches this list, even if the server host advertises PIPELINING support.
 Exim will not try to start a TLS session when delivering to any host that
 matches this list. See chapter &<<CHAPTLS>>& for details of TLS.
 
 Exim will not try to start a TLS session when delivering to any host that
 matches this list. See chapter &<<CHAPTLS>>& for details of TLS.
 

+.option hosts_verify_avoid_tls smtp "host list&!!" *
+.cindex "TLS" "avoiding for certain hosts"
+Exim will not try to start a TLS session for a verify callout,
+or when delivering in cutthrough mode,
+to any host that matches this list.
+Note that the default is to not use TLS.
+

 
 .option hosts_max_try smtp integer 5
 .cindex "host" "maximum number to try"
 
 .option hosts_max_try smtp integer 5
 .cindex "host" "maximum number to try"


@@ -22443,6 +22573,19 @@ This option specifies a certificate revocation list. The expanded value must
 be the name of a file that contains a CRL in PEM format.
 
 
 be the name of a file that contains a CRL in PEM format.
 
 

+.new
+.option tls_dh_min_bits smtp integer 1024
+.cindex "TLS" "Diffie-Hellman minimum acceptable size"
+When establishing a TLS session, if a ciphersuite which uses Diffie-Hellman
+key agreement is negotiated, the server will provide a large prime number
+for use.  This option establishes the minimum acceptable size of that number.
+If the parameter offered by the server is too small, then the TLS handshake
+will fail.
+
+Only supported when using GnuTLS.
+.wen
+
+

 .option tls_privatekey smtp string&!! unset
 .cindex "TLS" "client private key, location of"
 .vindex "&$host$&"
 .option tls_privatekey smtp string&!! unset
 .cindex "TLS" "client private key, location of"
 .vindex "&$host$&"


@@ -24996,6 +25139,13 @@ option).
 The &%tls_require_ciphers%& options operate differently, as described in the
 sections &<<SECTreqciphssl>>& and &<<SECTreqciphgnu>>&.
 .next
 The &%tls_require_ciphers%& options operate differently, as described in the
 sections &<<SECTreqciphssl>>& and &<<SECTreqciphgnu>>&.
 .next

+.new
+The &%tls_dh_min_bits%& SMTP transport option is only honoured by GnuTLS.
+When using OpenSSL, this option is ignored.
+(If an API is found to let OpenSSL be configured in this way,
+let the Exim Maintainers know and we'll likely use it).
+.wen
+.next

 Some other recently added features may only be available in one or the other.
 This should be documented with the feature.  If the documentation does not
 explicitly state that the feature is infeasible in the other TLS
 Some other recently added features may only be available in one or the other.
 This should be documented with the feature.  If the documentation does not
 explicitly state that the feature is infeasible in the other TLS


@@ -26707,6 +26857,25 @@ Notice that we put back the lower cased version afterwards, assuming that
 is what is wanted for subsequent tests.
 
 
 is what is wanted for subsequent tests.
 
 

+.new
+.vitem &*control&~=&~dscp/*&<&'value'&>
+.cindex "&ACL;" "setting DSCP value"
+.cindex "DSCP" "inbound"
+This option causes the DSCP value associated with the socket for the inbound
+connection to be adjusted to a given value, given as one of a number of fixed
+strings or to numeric value.
+The &%-bI:dscp%& option may be used to ask Exim which names it knows of.
+Common values include &`throughput`&, &`mincost`&, and on newer systems
+&`ef`&, &`af41`&, etc.  Numeric values may be in the range 0 to 0x3F.
+
+The outbound packets from Exim will be marked with this value in the header
+(for IPv4, the TOS field; for IPv6, the TCLASS field); there is no guarantee
+that these values will have any effect, not be stripped by networking
+equipment, or do much of anything without cooperation with your Network
+Engineer and those of all network operators between the source and destination.
+.wen
+
+

 .vitem &*control&~=&~debug/*&<&'options'&>
 .cindex "&ACL;" "enabling debug logging"
 .cindex "debugging" "enabling from an ACL"
 .vitem &*control&~=&~debug/*&<&'options'&>
 .cindex "&ACL;" "enabling debug logging"
 .cindex "debugging" "enabling from an ACL"