Check return values of setgid/setuid.

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index bd658e55e46550d7d6bf4686cf432faf99d2cd6c..160410bd347204bfa981a5980220f7c8242a756e 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -1544,7 +1544,6 @@ If a host is unreachable for a period of time, a number of messages may be
 waiting for it by the time it recovers, and sending them in a single SMTP
 connection is clearly beneficial. Whenever a delivery to a remote host is
 deferred,
-
 .cindex "hints database"
 Exim makes a note in its hints database, and whenever a successful
 SMTP delivery has happened, it looks to see if any other messages are waiting
@@ -1947,6 +1946,36 @@ support has not been tested for some time.
 
 
 
+.section "Dynamically loaded lookup module support" "SECTdynamicmodules"
+.cindex "lookup modules"
+.cindex "dynamic modules"
+.cindex ".so building"
+On some platforms, Exim supports not compiling all lookup types directly into
+the main binary, instead putting some into external modules which can be loaded
+on demand.
+This permits packagers to build Exim with support for lookups with extensive
+library dependencies without requiring all users to install all of those
+dependencies.
+Most, but not all, lookup types can be built this way.
+
+Set &`LOOKUP_MODULE_DIR`& to the directory into which the modules will be
+installed; Exim will only load modules from that directory, as a security
+measure.  You will need to set &`CFLAGS_DYNAMIC`& if not already defined
+for your OS; see &_OS/Makefile-Linux_& for an example.
+Some other requirements for adjusting &`EXTRALIBS`& may also be necessary,
+see &_src/EDITME_& for details.
+
+Then, for each module to be loaded dynamically, define the relevant
+&`LOOKUP_`&<&'lookup_type'&> flags to have the value "2" instead of "yes".
+For example, this will build in lsearch but load sqlite and mysql support
+on demand:
+.code
+LOOKUP_LSEARCH=yes
+LOOKUP_SQLITE=2
+LOOKUP_MYSQL=2
+.endd
+
+
 .section "The building process" "SECID29"
 .cindex "build directory"
 Once &_Local/Makefile_& (and &_Local/eximon.conf_&, if required) have been
@@ -15402,6 +15431,13 @@ are using OpenSSL, you can set &%tls_verify_certificates%& to the name of a
 directory containing certificate files. This does not work with GnuTLS; the
 option must be set to the name of a single file if you are using GnuTLS.
 
+These certificates should be for the certificate authorities trusted, rather
+than the public cert of individual clients.  With both OpenSSL and GnuTLS, if
+the value is a file then the certificates are sent by Exim as a server to
+connecting clients, defining the list of accepted certificate authorities.
+Thus the values defined should be considered public data.  To avoid this,
+use OpenSSL with a directory.
+
 
 .option tls_verify_hosts main "host list&!!" unset
 .cindex "TLS" "client certificate verification"
@@ -23753,7 +23789,7 @@ login:
   driver = plaintext
   public_name = LOGIN
   server_prompts = Username:: : Password::
-  server_condition = ${if and{{
+  server_condition = ${if and{{ \
     !eq{}{$auth1} }{ \
     ldapauth{user="cn=${quote_ldap_dn:$auth1},ou=people,o=example.org" \
              pass=${quote:$auth2} \
@@ -24967,6 +25003,19 @@ and try again later, but that is their problem, though it does waste some of
 your resources.
 
 
+.new
+.section "The SMTP DKIM ACL" "SECTDKIMACL"
+The &%acl_smtp_dkim%& ACL is available only when Exim is compiled with DKIM support
+enabled (which is the default).
+
+The ACL test specified by &%acl_smtp_dkim%& happens after a message has been
+received, and is executed for each DKIM signature found in a message.  If not
+otherwise specified, the default action is to accept.
+
+For details on the operation of DKIM, see chapter &<<CHID12>>&.
+.wen
+
+
 .section "The SMTP MIME ACL" "SECID194"
 The &%acl_smtp_mime%& option is available only when Exim is compiled with the
 content-scanning extension. For details, see chapter &<<CHAPexiscan>>&.
@@ -31006,8 +31055,8 @@ rejected (there seems little point) but instead just get qualified. HELO
 and EHLO act as RSET; VRFY, EXPN, ETRN and  HELP, act
 as NOOP; QUIT quits.
 
-No policy checking is done for BSMTP input. That is, no ACL is run at anytime.
-In this respect it is like non-SMTP local input.
+Minimal policy checking is done for BSMTP input. Only the non-SMTP
+ACL is run in the same way as for non-SMTP local input.
 
 If an error is detected while reading a message, including a missing &"."& at
 the end, Exim gives up immediately. It writes details of the error to the
@@ -34196,6 +34245,13 @@ arbitrary program's being run as exim, not as root.
 
 
 
+.section "Dynamic module directory" "SECTdynmoddir"
+Any dynamically loadable modules must be installed into the directory
+defined in &`LOOKUP_MODULE_DIR`& in &_Local/Makefile_& for Exim to permit
+loading it.
+
+
+
 .section "Use of sprintf()" "SECID279"
 .cindex "&[sprintf()]&"
 A large number of occurrences of &"sprintf"& in the code are actually calls to