From: Vladimír Čunát <vladimir.cunat@nic.cz>
Date: Wed, 12 Dec 2018 14:29:23 +0000 (+0100)
Subject: modules/{policy,view}: do not act if FAIL or DONE
X-Git-Tag: v3.2.0~6^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c16728f5c155cdf569eae960bb68e5d9d8e3683d;p=thirdparty%2Fknot-resolver.git

modules/{policy,view}: do not act if FAIL or DONE

Not all actions are destructive, but it seems generally expected that if
an earlier module or other code already transitioned the request into
a FAIL or DONE state, we don't want to apply rules anymore.
In particular, later rule actions would "overwrite" what previous
actions did.
---

diff --git a/modules/policy/policy.lua b/modules/policy/policy.lua
index 7a3fb6bbc..6e9492fb7 100644
--- a/modules/policy/policy.lua
+++ b/modules/policy/policy.lua
@@ -549,12 +549,18 @@ end
 -- as a dependency chain, e.g. r1,r2,r3 -> r3(r2(r1(state)))
 policy.layer = {
 	begin = function(state, req)
+		-- Don't act on "resolved" cases.
+		if bit.band(state, bit.bor(kres.FAIL, kres.DONE)) ~= 0 then return state end
+
 		req = kres.request_t(req)
 		return policy.evaluate(policy.rules, req, req:current(), state) or
 		       policy.evaluate(policy.special_names, req, req:current(), state) or
 		       state
 	end,
 	finish = function(state, req)
+		-- Don't act on "resolved" cases.
+		if bit.band(state, bit.bor(kres.FAIL, kres.DONE)) ~= 0 then return state end
+
 		req = kres.request_t(req)
 		return policy.evaluate(policy.postrules, req, req:current(), state) or state
 	end
diff --git a/modules/view/view.lua b/modules/view/view.lua
index 7e84ff29d..41157eb8d 100644
--- a/modules/view/view.lua
+++ b/modules/view/view.lua
@@ -106,7 +106,9 @@ end
 -- @function Module layers
 view.layer = {
 	begin = function(state, req)
-		if state == kres.FAIL then return state end
+		-- Don't act on "resolved" cases.
+		if bit.band(state, bit.bor(kres.FAIL, kres.DONE)) ~= 0 then return state end
+
 		req = kres.request_t(req)
 		evaluate(state, req)
 		return req.state