.cindex "tainted data"
If the origin of the data is an incoming message,
-the result of expanding this variable is tainted.
+the result of expanding this variable is tainted and may not
+be further expanded or used as a filename.
When an untainted version is needed, one should be obtained from
looking up the value in a local (therefore trusted) database.
Often &$domain_data$& is usable in this role.
.cindex "tainted data"
If the origin of the data is an incoming message,
-the result of expanding this variable is tainted.
+the result of expanding this variable is tainted and
+may not be further expanded or used as a filename.
&*Warning*&: the content of this variable is usually provided by a potential
attacker.
.vindex "&$tls_in_sni$&"
.vindex "&$tls_sni$&"
.cindex "TLS" "Server Name Indication"
+.cindex "TLS" SNI
+.cindex SNI "observability on server"
When a TLS session is being established, if the client sends the Server
Name Indication extension, the value will be placed in this variable.
If the variable appears in &%tls_certificate%& then this option and
.vitem &$tls_out_sni$&
.vindex "&$tls_out_sni$&"
.cindex "TLS" "Server Name Indication"
+.cindex "TLS" SNI
+.cindex SNI "observability in client"
During outbound
SMTP deliveries, this variable reflects the value of the &%tls_sni%& option on
the transport.
file is used, the &$tls_in_ourcert$& variable is unreliable.
The macro "_TLS_BAD_MULTICERT_IN_OURCERT" will be defined for those versions.
+.cindex SNI "selecting server certificate based on"
If the option contains &$tls_out_sni$& and Exim is built against OpenSSL, then
if the OpenSSL build supports TLS extensions and the TLS client sends the
Server Name Indication extension, then this option and others documented in
.option tls_sni smtp string&!! unset
.cindex "TLS" "Server Name Indication"
+.cindex "TLS" SNI
+.cindex SNI "setting in client"
.vindex "&$tls_sni$&"
If this option is set then it sets the $tls_out_sni variable and causes any
TLS session to pass this value as the Server Name Indication extension to
.section "Use of TLS Server Name Indication" "SECTtlssni"
.cindex "TLS" "Server Name Indication"
+.cindex "TLS" SNI
+.cindex SNI
.vindex "&$tls_in_sni$&"
.oindex "&%tls_in_sni%&"
With TLS1.0 or above, there is an extension mechanism by which extra
.section "Per-address filtering" "SECTperaddfil"
-.vindex "&$domain$&"
-.vindex "&$local_part$&"
+.vindex "&$domain_data$&"
+.vindex "&$local_part_data$&"
In contrast to the system filter, which is run just once per message for each
delivery attempt, it is also possible to set up a system-wide filtering
operation that runs once for each recipient address. In this case, variables
-such as &$local_part$& and &$domain$& can be used, and indeed, the choice of
-filter file could be made dependent on them. This is an example of a router
-which implements such a filter:
+such as &$local_part_data$& and &$domain_data$& can be used,
+and indeed, the choice of filter file could be made dependent on them.
+This is an example of a router which implements such a filter:
.code
central_filter:
check_local_user
.code
my_mailboxes:
driver = appendfile
- file = /var/mail/$domain/$local_part_data
+ file = /var/mail/$domain_data/$local_part_data
user = mail
.endd
This uses a directory of mailboxes for each domain. The &%user%& setting is
cases by testing the variable &$local_part_suffix$&. For example:
.code
if $local_part_suffix contains -special then
-save /home/$local_part/Mail/special
+save /home/$local_part_data/Mail/special
endif
.endd
If the filter file does not exist, or does not deal with such addresses, they
.next
.cindex "log" "TLS SNI"
.cindex "TLS" "logging SNI"
+.cindex SNI logging
&%tls_sni%&: When a message is received over an encrypted connection, and
the remote host provided the Server Name Indication extension, the SNI is
added to the log line, preceded by SNI=.