Merge branch 'hs/taintwarn'

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 61abb70c0751b8f368f1706f75a38a979a22aea4..05d8e6ed17511ac2959b1fca616c2923561a2e53 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -239,6 +239,14 @@
   <secondary>failure report</secondary>
   <see><emphasis>bounce message</emphasis></see>
 </indexterm>
   <secondary>failure report</secondary>
   <see><emphasis>bounce message</emphasis></see>
 </indexterm>

+<indexterm role="concept">
+  <primary>de-tainting</primary>
+  <see><emphasis>tainting, de-tainting</emphasis></see>
+</indexterm>
+<indexterm role="concept">
+  <primary>detainting</primary>
+  <see><emphasis>tainting, de-tainting</emphasis></see>
+</indexterm>

 <indexterm role="concept">
   <primary>dialup</primary>
   <see><emphasis>intermittently connected hosts</emphasis></see>
 <indexterm role="concept">
   <primary>dialup</primary>
   <see><emphasis>intermittently connected hosts</emphasis></see>


@@ -9606,6 +9614,8 @@ reasons,
 and expansion of data deriving from the sender (&"tainted data"&)
 .new
 is not permitted (including acessing a file using a tainted name).
 and expansion of data deriving from the sender (&"tainted data"&)
 .new
 is not permitted (including acessing a file using a tainted name).

+The main config option &%allow_insecure_tainted_data%& can be used as
+mitigation during uprades to more secure configurations.

 .wen
 
 .new
 .wen
 
 .new


@@ -14590,6 +14600,7 @@ listed in more than one group.
 .section "Miscellaneous" "SECID96"
 .table2
 .row &%add_environment%&             "environment variables"
 .section "Miscellaneous" "SECID96"
 .table2
 .row &%add_environment%&             "environment variables"

+.row &%allow_insecure_tainted_data%& "turn taint errors into warnings"

 .row &%bi_command%&                  "to run for &%-bi%& command line option"
 .row &%debug_store%&                 "do extra internal checks"
 .row &%disable_ipv6%&                "do no IPv6 processing"
 .row &%bi_command%&                  "to run for &%-bi%& command line option"
 .row &%debug_store%&                 "do extra internal checks"
 .row &%disable_ipv6%&                "do no IPv6 processing"


@@ -14714,6 +14725,7 @@ listed in more than one group.
 .row &%notifier_socket%&             "override compiled-in value"
 .row &%pid_file_path%&               "override compiled-in value"
 .row &%queue_run_max%&               "maximum simultaneous queue runners"
 .row &%notifier_socket%&             "override compiled-in value"
 .row &%pid_file_path%&               "override compiled-in value"
 .row &%queue_run_max%&               "maximum simultaneous queue runners"

+.row &%smtp_backlog_monitor%&        "level to log listen backlog"

 .endtable
 
 
 .endtable
 
 


@@ -15200,6 +15212,18 @@ domains (defined in the named domain list &%local_domains%& in the default
 configuration). This &"magic string"& matches the domain literal form of all
 the local host's IP addresses.
 
 configuration). This &"magic string"& matches the domain literal form of all
 the local host's IP addresses.
 

+.new
+.option allow_insecure_tainted_data main boolean false
+.cindex "de-tainting"
+.oindex "allow_insecure_tainted_data"
+The handling of tainted data may break older (pre 4.94) configurations.
+Setting this option to "true" turns taint errors (which result in a temporary
+message rejection) into warnings. This option is meant as mitigation only
+and deprecated already today. Future releases of Exim may ignore it.
+The &%taint%& log selector can be used to suppress even the warnings.
+.wen
+
+

 
 .option allow_mx_to_ip main boolean false
 .cindex "MX record" "pointing to IP address"
 
 .option allow_mx_to_ip main boolean false
 .cindex "MX record" "pointing to IP address"


@@ -17394,7 +17418,7 @@ or if the message was submitted locally (not using TCP/IP), and the &%-bnq%&
 option was not set.
 
 
 option was not set.
 
 

-.option recipients_max main integer 0
+.option recipients_max main integer 50000

 .cindex "limit" "number of recipients"
 .cindex "recipient" "maximum number"
 If this option is set greater than zero, it specifies the maximum number of
 .cindex "limit" "number of recipients"
 .cindex "recipient" "maximum number"
 If this option is set greater than zero, it specifies the maximum number of


@@ -17732,6 +17756,14 @@ messages, it is also used as the default for HELO commands in callout
 verification if there is no remote transport from which to obtain a
 &%helo_data%& value.
 
 verification if there is no remote transport from which to obtain a
 &%helo_data%& value.
 

+.option smtp_backlog_monitor main integer 0
+.cindex "connection backlog" monitoring
+If this option is set to greater than zero, and the backlog of available
+TCP connections on a socket listening for SMTP is larger than it, a line
+is logged giving the value and the socket address and port.
+The value is retrived jsut before an accept call.
+This facility is only available on Linux.
+

 .option smtp_banner main string&!! "see below"
 .cindex "SMTP" "welcome banner"
 .cindex "banner for SMTP"
 .option smtp_banner main string&!! "see below"
 .cindex "SMTP" "welcome banner"
 .cindex "banner for SMTP"


@@ -17762,7 +17794,7 @@ is zero). If there isn't enough space, a temporary error code is returned.
 
 
 .option smtp_connect_backlog main integer 20
 
 
 .option smtp_connect_backlog main integer 20

-.cindex "connection backlog"
+.cindex "connection backlog" "set maximum"

 .cindex "SMTP" "connection backlog"
 .cindex "backlog of connections"
 This option specifies a maximum number of waiting SMTP connections. Exim passes
 .cindex "SMTP" "connection backlog"
 .cindex "backlog of connections"
 This option specifies a maximum number of waiting SMTP connections. Exim passes


@@ -21515,7 +21547,7 @@ The text is not included in the response to an EXPN command. In non-SMTP cases
 the text is included in the error message that Exim generates.
 
 .cindex "SMTP" "error codes"
 the text is included in the error message that Exim generates.
 
 .cindex "SMTP" "error codes"

-By default, Exim sends a 451 SMTP code for a &':defer:'&, and 550 for
+By default for verify, Exim sends a 451 SMTP code for a &':defer:'&, and 550 for

 &':fail:'&. However, if the message starts with three digits followed by a
 space, optionally followed by an extended code of the form &'n.n.n'&, also
 followed by a space, and the very first digit is the same as the default error
 &':fail:'&. However, if the message starts with three digits followed by a
 space, optionally followed by an extended code of the form &'n.n.n'&, also
 followed by a space, and the very first digit is the same as the default error


@@ -25632,6 +25664,11 @@ There will be no fallback to in-clear communication.
 See the &%dnssec_request_domains%& router and transport options.
 See section &<<SECDANE>>&.
 
 See the &%dnssec_request_domains%& router and transport options.
 See section &<<SECDANE>>&.
 

+.option hosts_require_helo smtp "host list&!!" *
+.cindex "HELO/EHLO" requiring
+Exim will require an accepted HELO or EHLO command from a host matching
+this list, before accepting a MAIL command.
+

 .option hosts_require_ocsp smtp "host list&!!" unset
 .cindex "TLS" "requiring for certain servers"
 Exim will request, and check for a valid Certificate Status being given, on a
 .option hosts_require_ocsp smtp "host list&!!" unset
 .cindex "TLS" "requiring for certain servers"
 Exim will request, and check for a valid Certificate Status being given, on a


@@ -38736,6 +38773,7 @@ selection marked by asterisks:
 &` smtp_protocol_error        `&  SMTP protocol errors
 &` smtp_syntax_error          `&  SMTP syntax errors
 &` subject                    `&  contents of &'Subject:'& on <= lines
 &` smtp_protocol_error        `&  SMTP protocol errors
 &` smtp_syntax_error          `&  SMTP syntax errors
 &` subject                    `&  contents of &'Subject:'& on <= lines

+&`*taint                      `&  taint errors or warnings

 &`*tls_certificate_verified   `&  certificate verification status
 &`*tls_cipher                 `&  TLS cipher suite on <= and => lines
 &` tls_peerdn                 `&  TLS peer DN on <= and => lines
 &`*tls_certificate_verified   `&  certificate verification status
 &`*tls_cipher                 `&  TLS cipher suite on <= and => lines
 &` tls_peerdn                 `&  TLS peer DN on <= and => lines


@@ -39131,6 +39169,11 @@ using a CA trust anchor,
 &`CV=dane`& if using a DNS trust anchor,
 and &`CV=no`& if not.
 .next
 &`CV=dane`& if using a DNS trust anchor,
 and &`CV=no`& if not.
 .next

+.cindex "log" "Taint warnings"
+&%taint%&: Log warnings about tainted data. This selector can't be
+turned of if &%allow_insecure_tainted_data%& is false (which is the
+default).
+.next

 .cindex "log" "TLS cipher"
 .cindex "TLS" "logging cipher"
 &%tls_cipher%&: When a message is sent or received over an encrypted
 .cindex "log" "TLS cipher"
 .cindex "TLS" "logging cipher"
 &%tls_cipher%&: When a message is sent or received over an encrypted