From: Vladimír Čunát <vladimir.cunat@nic.cz>
Date: Tue, 10 Aug 2021 08:42:54 +0000 (+0200)
Subject: modules/dns64: add kr_query::flags.DNS64_DISABLE
X-Git-Tag: v5.4.2~8^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=447654a51fa04120dfb14ec2c1b25690b2b2e312;p=thirdparty%2Fknot-resolver.git

modules/dns64: add kr_query::flags.DNS64_DISABLE

It's not a perfect solution and with the future policy engine it will
hopefully be better, but it's really trivial to add this already.
(should've done that years ago)
---

diff --git a/NEWS b/NEWS
index 8926b2f3f..c64950e01 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,7 @@ Knot Resolver 5.4.2 (2021-0m-dd)
 Improvements
 ------------
 - dns64 module: also map the reverse (PTR) subtree (#478, !1201)
+- dns64 module: allow disabling based on client address (#368, !1201)
 
 
 Knot Resolver 5.4.1 (2021-08-19)
diff --git a/daemon/lua/kres-gen-29.lua b/daemon/lua/kres-gen-29.lua
index 6a8a4cf3e..6861466b0 100644
--- a/daemon/lua/kres-gen-29.lua
+++ b/daemon/lua/kres-gen-29.lua
@@ -134,6 +134,7 @@ struct kr_qflags {
 	_Bool CACHE_TRIED : 1;
 	_Bool NO_NS_FOUND : 1;
 	_Bool PKT_IS_SANE : 1;
+	_Bool DNS64_DISABLE : 1;
 };
 typedef struct ranked_rr_array_entry {
 	uint32_t qry_uid;
diff --git a/daemon/lua/kres-gen-31.lua b/daemon/lua/kres-gen-31.lua
index af069ba61..b8dd5e336 100644
--- a/daemon/lua/kres-gen-31.lua
+++ b/daemon/lua/kres-gen-31.lua
@@ -134,6 +134,7 @@ struct kr_qflags {
 	_Bool CACHE_TRIED : 1;
 	_Bool NO_NS_FOUND : 1;
 	_Bool PKT_IS_SANE : 1;
+	_Bool DNS64_DISABLE : 1;
 };
 typedef struct ranked_rr_array_entry {
 	uint32_t qry_uid;
diff --git a/lib/rplan.h b/lib/rplan.h
index 5120521d7..73fe6f7f0 100644
--- a/lib/rplan.h
+++ b/lib/rplan.h
@@ -53,6 +53,7 @@ struct kr_qflags {
 	bool NO_NS_FOUND : 1;    /**< No valid NS found during last PRODUCE stage. */
 	bool PKT_IS_SANE : 1;    /**< Set by iterator in consume phase to indicate whether
 				  * some basic aspects of the packet are OK, e.g. QNAME. */
+	bool DNS64_DISABLE : 1;  /**< Don't do any DNS64 stuff (meant for view:addr). */
 };
 
 /** Combine flags together.  This means set union for simple flags. */
diff --git a/modules/dns64/dns64.lua b/modules/dns64/dns64.lua
index f4a68e063..af8926f8f 100644
--- a/modules/dns64/dns64.lua
+++ b/modules/dns64/dns64.lua
@@ -43,7 +43,7 @@ function M.layer.consume(state, req, pkt)
 	if state == kres.FAIL then return state end
 	local qry = req:current()
 	-- Observe only final answers in IN class where request has no CD flag.
-	if M.proxy == nil or not qry.flags.RESOLVED
+	if M.proxy == nil or not qry.flags.RESOLVED or qry.flags.DNS64_DISABLE
 			or pkt:qclass() ~= kres.class.IN or req.qsource.packet:cd() then
 		return state
 	end
@@ -131,7 +131,7 @@ end
 function M.layer.produce(_, req, pkt)
 	local qry = req.current_query
 	local sname = qry.sname
-	if ffi.C.knot_dname_in_bailiwick(sname, M.rev_suffix) < 0
+	if ffi.C.knot_dname_in_bailiwick(sname, M.rev_suffix) < 0 or qry.flags.DNS64_DISABLE
 		then return end
 	-- Update packet question if it was minimized.
 	qry.flags.NO_MINIMIZE = true