add answer-cookie as a obsolete option

CHANGES

@@ -1,3 +1,7 @@
+4967.	[cleanup]	Add "answer-cookie" to the parser, marked obsolete.
+
+4966.	[placeholder]
+
 4965.	[func]		Add support for marking options as deprecated.
 			[GL #322]
 

bin/named/config.c

@@ -47,6 +47,7 @@
 /*% default configuration */
 static char defaultconf[] = "\
 options {\n\
+#	answer-cookie <obsolete>;\n\
 	automatic-interface-scan yes;\n\
 	bindkeys-file \"" NAMED_SYSCONFDIR "/bind.keys\";\n\
 #	blackhole {none;};\n"

doc/arm/Bv9ARM-book.xml

@@ -5776,7 +5776,7 @@ options {
 	      <term><command>fetch-glue</command></term>
 	      <listitem>
 		<para>
-		  This option is obsolete.
+		  <emphasis>This option is obsolete</emphasis>.
 		  In BIND 8, <userinput>fetch-glue yes</userinput>
 		  caused the server to attempt to fetch glue resource records
 		  it
@@ -6080,6 +6080,18 @@ options {
 	      </listitem>
 	    </varlistentry>
 
+	    <varlistentry>
+	      <term><command>answer-cookie</command></term>
+	      <listitem>
+		<para>
+		  <emphasis>This option is obsolete</emphasis>.
+		  This option was used to prevent the sending of
+		  a DNS COOKIE option in response to a request with
+		  one present in BIND 9.11 and BIND 9.12.
+		</para>
+	      </listitem>
+	    </varlistentry>
+
 	    <varlistentry>
 	      <term><command>send-cookie</command></term>
 	      <listitem>

lib/isccfg/namedconf.c

@@ -1030,6 +1030,7 @@ static cfg_type_t cfg_type_fstrm_model = {
  */
 static cfg_clausedef_t
 options_clauses[] = {
+	{ "answer-cookie", &cfg_type_boolean, CFG_CLAUSEFLAG_OBSOLETE },
 	{ "automatic-interface-scan", &cfg_type_boolean, 0 },
 	{ "avoid-v4-udp-ports", &cfg_type_bracketed_portlist, 0 },
 	{ "avoid-v6-udp-ports", &cfg_type_bracketed_portlist, 0 },