X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/a24e9982bdef1e7d738c8d4592705899d15d385d..cb45303cf2a8d9922702f13db42b3285c48f6aa7:/doc/doc-docbook/spec.xfpt
diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 6c0ac922d..7f96768f7 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -239,14 +239,6 @@
failure report
bounce message
-
- de-tainting
- tainting, de-tainting
-
-
- detainting
- tainting, de-tainting
-
dialup
intermittently connected hosts
@@ -1841,6 +1833,9 @@ 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.
+.new
+You can set USE_NDBM if needed to override an operating system default.
+.wen
At the lowest level, the build-time configuration sets none of these options,
thereby assuming an interface of type (1). However, some operating system
@@ -1855,7 +1850,11 @@ in one of these lines:
.code
DBMLIB = -ldb
DBMLIB = -ltdb
+DBMLIB = -lgdbm -lgdbm_compat
.endd
+.new
+The last of those was for a Linux having GDBM provide emulated NDBM facilities.
+.wen
Settings like that will work if the DBM library is installed in the standard
place. Sometimes it is not, and the library's header file may also not be in
the default path. You may need to set INCLUDE to specify where the header
@@ -6840,6 +6839,12 @@ version of the lookup key.
The &'query-style'& type accepts a generalized database query. No particular
key value is assumed by Exim for query-style lookups. You can use whichever
Exim variables you need to construct the database query.
+.cindex "tainted data" "quoting for lookups"
+.new
+If tainted data is used in the query then it should be quuted by
+using the &*${quote_*&<&'lookup-type'&>&*:*&<&'string'&>&*}*& expansion operator
+appropriate for the lookup.
+.wen
.endlist
The code for each lookup type is in a separate source file that is included in
@@ -6993,7 +6998,7 @@ IPv4, in dotted-quad form. (Exim converts IPv4-mapped IPv6 addresses to this
notation before executing the lookup.)
One option is supported, "ret=full", to request the return of the entire line
-rather than omitting the key porttion.
+rather than omitting the key portion.
Note however that the key portion will have been de-quoted.
.next
@@ -9621,8 +9626,6 @@ reasons,
.cindex expansion "tainted data"
and expansion of data deriving from the sender (&"tainted data"&)
is not permitted (including acessing a file using a tainted name).
-The main config option &%allow_insecure_tainted_data%& can be used as
-mitigation during uprades to more secure configurations.
Common ways of obtaining untainted equivalents of variables with
tainted values
@@ -10660,16 +10663,28 @@ expansion items.
This item inserts &"raw"& header lines. It is described with the &%header%&
expansion item in section &<>& above.
-.vitem "&*${run{*&<&'command'&>&*&~*&<&'args'&>&*}{*&<&'string1'&>&*}&&&
+.vitem "&*${run <&'options'&> {*&<&'command&~arg&~list'&>&*}{*&<&'string1'&>&*}&&&
{*&<&'string2'&>&*}}*&"
.cindex "expansion" "running a command"
.cindex "&%run%& expansion item"
-The command and its arguments are first expanded as one string. The string is
-split apart into individual arguments by spaces, and then the command is run
+This item runs an external command, as a subprocess.
+.new
+One option is supported after the word &'run'&, comma-separated.
+
+If the option &'preexpand'& is not used,
+the command string is split into individual arguments by spaces
+and then each argument is expanded.
+Then the command is run
in a separate process, but under the same uid and gid. As in other command
executions from Exim, a shell is not used by default. If the command requires
a shell, you must explicitly code it.
+The command name may not be tainted, but the remaining arguments can be.
+If the option &'preexpand'& is used,
+.wen
+the command and its arguments are first expanded as one string. The result is
+split apart into individual arguments by spaces, and then the command is run
+as above.
Since the arguments are split by spaces, when there is a variable expansion
which has an empty result, it will cause the situation that the argument will
simply be omitted when the program is actually executed by Exim. If the
@@ -10680,6 +10695,9 @@ in a string containing quotes, because it would interfere with the quotes
around the command arguments. A possible guard against this is to wrap the
variable in the &%sg%& operator to change any quote marks to some other
character.
+.new
+Neither the command nor any argument may be tainted.
+.wen
The standard input for the command exists, but is empty. The standard output
and standard error are set to the same file descriptor.
@@ -11899,6 +11917,19 @@ ${if inlisti{Needle}{fOo:NeeDLE:bAr}}
${if forany{fOo:NeeDLE:bAr}{eqi{$item}{Needle}}}
.endd
+.new
+The variable &$value$& will be set for a successful match and can be
+used in the success clause of an &%if%& expansion item using the condition.
+.cindex "tainted data" "de-tainting"
+It will have the same taint status as the list; expansions such as
+.code
+${if inlist {$h_mycode:} {0 : 1 : 42} {$value}}
+.endd
+can be used for de-tainting.
+Any previous &$value$& is restored after the if.
+.wen
+
+
.vitem &*isip&~{*&<&'string'&>&*}*& &&&
&*isip4&~{*&<&'string'&>&*}*& &&&
&*isip6&~{*&<&'string'&>&*}*&
@@ -12095,6 +12126,18 @@ item can be used, as in all address lists, to cause subsequent items to
have their local parts matched casefully. Domains are always matched
caselessly.
+.new
+The variable &$value$& will be set for a successful match and can be
+used in the success clause of an &%if%& expansion item using the condition.
+.cindex "tainted data" "de-tainting"
+It will have the same taint status as the list; expansions such as
+.code
+${if match_local_part {$local_part} {alice : bill : charlotte : dave} {$value}}
+.endd
+can be used for de-tainting.
+Any previous &$value$& is restored after the if.
+.wen
+
Note that <&'string2'&> is not itself subject to string expansion, unless
Exim was built with the EXPAND_LISTMATCH_RHS option.
@@ -14602,7 +14645,6 @@ listed in more than one group.
.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"
@@ -15216,17 +15258,6 @@ 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.
-.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.
-
-
-
.option allow_mx_to_ip main boolean false
.cindex "MX record" "pointing to IP address"
It appears that more and more DNS zone administrators are breaking the rules
@@ -25477,7 +25508,8 @@ servers or different local IP addresses. For example, if you want the string
that is used for &%helo_data%& to be obtained by a DNS lookup of the outgoing
interface address, you could use this:
.code
-helo_data = ${lookup dnsdb{ptr=$sending_ip_address}{$value}\
+helo_data = ${lookup dnsdb{ptr=$sending_ip_address} \
+ {${listextract{1}{<\n $value}}} \
{$primary_hostname}}
.endd
The use of &%helo_data%& applies both to sending messages and when doing
@@ -25550,7 +25582,10 @@ so combines well with TCP Fast Open.
See also the &%pipelining_connect_advertise_hosts%& main option.
Note:
-When the facility is used, the transport &%helo_data%& option
+.new
+When the facility is used, if the transport &%interface%& option is unset
+the &%helo_data%& option
+.wen
will be expanded before the &$sending_ip_address$& variable
is filled in.
A check is made for the use of that variable, without the
@@ -38894,7 +38929,6 @@ selection marked by asterisks:
&` 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
@@ -39288,11 +39322,6 @@ using a CA trust anchor,
&`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
@@ -39437,9 +39466,6 @@ or (in case &*-a*& switch is specified)
.code
exim -bp
.endd
-The &*-C*& option is used to specify an alternate &_exim.conf_& which might
-contain alternate exim configuration the queue management might be using.
-
to obtain a queue listing, and then greps the output to select messages
that match given criteria. The following selection options are available:
@@ -39496,7 +39522,22 @@ Display messages in reverse order.
Include delivered recipients in queue listing.
.endlist
+The following options give alternates for configuration:
+
+.vlist
+.vitem &*-C*&&~<&'config&~file'&>
+is used to specify an alternate &_exim.conf_& which might
+contain alternate exim configuration the queue management might be using.
+
+.vitem &*-E*&&~<&'path'&>
+can be used to specify a path for the exim binary,
+overriding the built-in one.
+.endlist
+
There is one more option, &%-h%&, which outputs a list of options.
+.new
+At least one selection option, or either the &*-c*& or &*-h*& option, must be given.
+.wen
@@ -41015,8 +41056,18 @@ was received, in the conventional Unix form &-- the number of seconds since the
start of the epoch. The second number is a count of the number of messages
warning of delayed delivery that have been sent to the sender.
-There follow a number of lines starting with a hyphen. These can appear in any
-order, and are omitted when not relevant:
+.new
+There follow a number of lines starting with a hyphen.
+These contain variables, can appear in any
+order, and are omitted when not relevant.
+
+If there is a second hyphen after the first,
+the corresponding data is tainted.
+If there is a value in parentheses, the data is quoted for a lookup.
+
+The following word specifies a variable,
+and the remainder of the item depends on the variable.
+.wen
.vlist
.vitem "&%-acl%&&~<&'number'&>&~<&'length'&>"
@@ -41172,9 +41223,6 @@ was received from the client, this records the Distinguished Name from that
certificate.
.endlist
-Any of the above may have an extra hyphen prepended, to indicate the the
-corresponding data is untrusted.
-
Following the options there is a list of those addresses to which the message
is not to be delivered. This set of addresses is initialized from the command
line when the &%-t%& option is used and &%extract_addresses_remove_arguments%&