Make return value explicit

Author: Frank Denis

dnscrypt-proxy/proxy.go

@@ -572,10 +572,10 @@ func (proxy *Proxy) clientsCountDec() {
 	}
 }
 
-func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string, query []byte, clientAddr *net.Addr, clientPc net.Conn, start time.Time, onlyCached bool) (response []byte) {
-	response = nil
+func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string, query []byte, clientAddr *net.Addr, clientPc net.Conn, start time.Time, onlyCached bool) []byte {
+	var response []byte = nil
 	if len(query) < MinDNSPacketSize {
-		return
+		return response
 	}
 	pluginsState := NewPluginsState(proxy, clientProto, clientAddr, serverProto, start)
 	serverName := "-"
@@ -587,25 +587,25 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 	}
 	query, _ = pluginsState.ApplyQueryPlugins(&proxy.pluginsGlobals, query, needsEDNS0Padding)
 	if len(query) < MinDNSPacketSize || len(query) > MaxDNSPacketSize {
-		return
+		return response
 	}
 	if pluginsState.action == PluginsActionDrop {
 		pluginsState.returnCode = PluginsReturnCodeDrop
 		pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-		return
+		return response
 	}
 	var err error
 	if pluginsState.synthResponse != nil {
 		response, err = pluginsState.synthResponse.PackBuffer(response)
 		if err != nil {
 			pluginsState.returnCode = PluginsReturnCodeParseError
 			pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-			return
+			return response
 		}
 	}
 	if onlyCached {
 		if len(response) == 0 {
-			return
+			return response
 		}
 		serverInfo = nil
 	}
@@ -622,7 +622,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 			if err != nil {
 				pluginsState.returnCode = PluginsReturnCodeParseError
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-				return
+				return response
 			}
 			serverInfo.noticeBegin(proxy)
 			if serverProto == "udp" {
@@ -640,7 +640,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 					if err != nil {
 						pluginsState.returnCode = PluginsReturnCodeParseError
 						pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-						return
+						return response
 					}
 					response, err = proxy.exchangeWithTCPServer(serverInfo, sharedKey, encryptedQuery, clientNonce)
 				}
@@ -661,7 +661,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 				}
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 				serverInfo.noticeFailure(proxy)
-				return
+				return response
 			}
 		} else if serverInfo.Proto == stamps.StampProtoTypeDoH {
 			tid := TransactionID(query)
@@ -680,7 +680,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 				pluginsState.returnCode = PluginsReturnCodeNetworkError
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 				serverInfo.noticeFailure(proxy)
-				return
+				return response
 			}
 			if response == nil {
 				response = serverResponse
@@ -691,7 +691,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 		} else if serverInfo.Proto == stamps.StampProtoTypeODoHTarget {
 			tid := TransactionID(query)
 			if len(serverInfo.odohTargetConfigs) == 0 {
-				return
+				return response
 			}
 			target := serverInfo.odohTargetConfigs[rand.Intn(len(serverInfo.odohTargetConfigs))]
 			odohQuery, err := target.encryptQuery(query)
@@ -738,7 +738,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 				pluginsState.returnCode = PluginsReturnCodeNetworkError
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 				serverInfo.noticeFailure(proxy)
-				return
+				return response
 			}
 		} else {
 			dlog.Fatal("Unsupported protocol")
@@ -747,26 +747,26 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 			pluginsState.returnCode = PluginsReturnCodeParseError
 			pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 			serverInfo.noticeFailure(proxy)
-			return
+			return response
 		}
 		response, err = pluginsState.ApplyResponsePlugins(&proxy.pluginsGlobals, response, ttl)
 		if err != nil {
 			pluginsState.returnCode = PluginsReturnCodeParseError
 			pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 			serverInfo.noticeFailure(proxy)
-			return
+			return response
 		}
 		if pluginsState.action == PluginsActionDrop {
 			pluginsState.returnCode = PluginsReturnCodeDrop
 			pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-			return
+			return response
 		}
 		if pluginsState.synthResponse != nil {
 			response, err = pluginsState.synthResponse.PackBuffer(response)
 			if err != nil {
 				pluginsState.returnCode = PluginsReturnCodeParseError
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-				return
+				return response
 			}
 		}
 		if rcode := Rcode(response); rcode == dns.RcodeServerFailure { // SERVFAIL
@@ -790,15 +790,15 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 		if serverInfo != nil {
 			serverInfo.noticeFailure(proxy)
 		}
-		return
+		return response
 	}
 	if clientProto == "udp" {
 		if len(response) > pluginsState.maxUnencryptedUDPSafePayloadSize {
 			response, err = TruncatedResponse(response)
 			if err != nil {
 				pluginsState.returnCode = PluginsReturnCodeParseError
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
-				return
+				return response
 			}
 		}
 		clientPc.(net.PacketConn).WriteTo(response, *clientAddr)
@@ -815,7 +815,7 @@ func (proxy *Proxy) processIncomingQuery(clientProto string, serverProto string,
 			if serverInfo != nil {
 				serverInfo.noticeFailure(proxy)
 			}
-			return
+			return response
 		}
 		if clientPc != nil {
 			clientPc.Write(response)