Cache Plugin: return non-fixed TTL for cached entries (refactor)

dnscrypt-proxy/dnsutils.go

@@ -85,22 +85,33 @@ func getMinTTL(msg *dns.Msg, minTTL uint32, maxTTL uint32, negCacheMinTTL uint32
 
 func setMaxTTL(msg *dns.Msg, ttl uint32, force bool) {
 	for _, rr := range msg.Answer {
-		if (ttl < rr.Header().Ttl) || force {
+		if ttl < rr.Header().Ttl {
 			rr.Header().Ttl = ttl
 		}
 	}
 	for _, rr := range msg.Ns {
-    if (ttl < rr.Header().Ttl) || force {
+	  if ttl < rr.Header().Ttl {
 			rr.Header().Ttl = ttl
 		}
 	}
 	for _, rr := range msg.Extra {
-    if (ttl < rr.Header().Ttl) || force {
+	  if ttl < rr.Header().Ttl {
 			rr.Header().Ttl = ttl
 		}
 	}
 }
 
 func updateTTL(msg *dns.Msg, expiration time.Time) {
-  setMaxTTL(msg, uint32(time.Until(expiration) / time.Second), true)
+
+	ttl := uint32(time.Until(expiration) / time.Second)
+
+	for _, rr := range msg.Answer {
+	    rr.Header().Ttl = ttl
+	}
+	for _, rr := range msg.Ns {
+	    rr.Header().Ttl = ttl
+	}
+	for _, rr := range msg.Extra {
+	    rr.Header().Ttl = ttl
+	}
 }

dnscrypt-proxy/plugin_cache.go

@@ -71,7 +71,7 @@ func (plugin *PluginCacheResponse) Eval(pluginsState *PluginsState, msg *dns.Msg
 	}
 	plugin.cachedResponses.cache.Add(cacheKey, cachedResponse)
 
-  updateTTL(msg, cachedResponse.expiration)
+	updateTTL(msg, cachedResponse.expiration)
 	return nil
 }
 
@@ -120,7 +120,7 @@ func (plugin *PluginCache) Eval(pluginsState *PluginsState, msg *dns.Msg) error
 		return nil
 	}
 
-  updateTTL(&cached.msg, cached.expiration)
+	updateTTL(&cached.msg, cached.expiration)
 
 	synth := cached.msg
 	synth.Id = msg.Id

dnscrypt-proxy/plugins.go

@@ -178,7 +178,7 @@ func (pluginsState *PluginsState) ApplyResponsePlugins(pluginsGlobals *PluginsGl
 	}
 	pluginsGlobals.RUnlock()
 	if ttl != nil {
-		setMaxTTL(&msg, *ttl, false)
+		setMaxTTL(&msg, *ttl)
 	}
 	packet2, err := msg.PackBuffer(packet)
 	if err != nil {