From ac6fd3db3970e71e6a5eb182648386091fe73e0d Mon Sep 17 00:00:00 2001
From: Alison Winters <alisonatwork@outlook.com>
Date: Sat, 19 Oct 2019 16:15:41 +0800
Subject: [PATCH] differentiate between timeout and other error for dnscrypt
 servers

---
 dnscrypt-proxy/plugins.go | 2 ++
 dnscrypt-proxy/proxy.go   | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/dnscrypt-proxy/plugins.go b/dnscrypt-proxy/plugins.go
index a350f740..55287c12 100644
--- a/dnscrypt-proxy/plugins.go
+++ b/dnscrypt-proxy/plugins.go
@@ -44,6 +44,7 @@ const (
 	PluginsReturnCodeResponseError
 	PluginsReturnCodeServerError
 	PluginsReturnCodeCloak
+	PluginsReturnCodeServerTimeout
 )
 
 var PluginsReturnCodeToString = map[PluginsReturnCode]string{
@@ -57,6 +58,7 @@ var PluginsReturnCodeToString = map[PluginsReturnCode]string{
 	PluginsReturnCodeResponseError: "RESPONSE_ERROR",
 	PluginsReturnCodeServerError:   "SERVER_ERROR",
 	PluginsReturnCodeCloak:         "CLOAK",
+	PluginsReturnCodeServerTimeout: "SERVER_TIMEOUT",
 }
 
 type PluginsState struct {
diff --git a/dnscrypt-proxy/proxy.go b/dnscrypt-proxy/proxy.go
index 53ae94fc..feaf3640 100644
--- a/dnscrypt-proxy/proxy.go
+++ b/dnscrypt-proxy/proxy.go
@@ -419,7 +419,11 @@ func (proxy *Proxy) processIncomingQuery(serverInfo *ServerInfo, clientProto str
 				response, err = proxy.exchangeWithTCPServer(serverInfo, sharedKey, encryptedQuery, clientNonce)
 			}
 			if err != nil {
-				pluginsState.returnCode = PluginsReturnCodeServerError
+				if neterr, ok := err.(net.Error); ok && neterr.Timeout() {
+					pluginsState.returnCode = PluginsReturnCodeServerTimeout
+				} else {
+					pluginsState.returnCode = PluginsReturnCodeServerError
+				}
 				pluginsState.ApplyLoggingPlugins(&proxy.pluginsGlobals)
 				serverInfo.noticeFailure(proxy)
 				return