From 28fd80f4e09e60401685b0d587236b9331ef5cbd Mon Sep 17 00:00:00 2001
From: Davide De Rosa <keeshux@gmail.com>
Date: Wed, 17 Apr 2019 00:42:07 +0200
Subject: [PATCH 1/3] Treat empty DNS servers as nil

Empty local DNS array was pretty much hiding server-pushed DNS.
---
 TunnelKit/Sources/AppExtension/TunnelKitProvider.swift | 5 ++++-
 TunnelKit/Sources/Core/ConfigurationParser.swift       | 7 +++++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
index 83e3fef..6152ac8 100644
--- a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
+++ b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
@@ -560,7 +560,10 @@ extension TunnelKitProvider: SessionProxyDelegate {
             ipv6Settings?.excludedRoutes = []
         }
         
-        let dnsServers = cfg.sessionConfiguration.dnsServers ?? reply.options.dnsServers
+        var dnsServers = cfg.sessionConfiguration.dnsServers
+        if dnsServers?.isEmpty ?? true {
+            dnsServers = reply.options.dnsServers
+        }
         let searchDomain = cfg.sessionConfiguration.searchDomain ?? reply.options.searchDomain
         let dnsSettings = NEDNSSettings(servers: dnsServers ?? [])
         dnsSettings.domainName = searchDomain
diff --git a/TunnelKit/Sources/Core/ConfigurationParser.swift b/TunnelKit/Sources/Core/ConfigurationParser.swift
index 390ac20..fbfe683 100644
--- a/TunnelKit/Sources/Core/ConfigurationParser.swift
+++ b/TunnelKit/Sources/Core/ConfigurationParser.swift
@@ -199,7 +199,7 @@ public class ConfigurationParser {
         var optGateway4Arguments: [String]?
         var optRoutes4: [(String, String, String?)] = [] // address, netmask, gateway
         var optRoutes6: [(String, UInt8, String?)] = [] // destination, prefix, gateway
-        var optDNSServers: [String] = []
+        var optDNSServers: [String]?
         var optSearchDomain: String?
         var optHTTPProxy: Proxy?
         var optHTTPSProxy: Proxy?
@@ -482,7 +482,10 @@ public class ConfigurationParser {
                 guard $0.count == 2 else {
                     return
                 }
-                optDNSServers.append($0[1])
+                if optDNSServers == nil {
+                    optDNSServers = []
+                }
+                optDNSServers?.append($0[1])
             }
             Regex.domain.enumerateArguments(in: line) {
                 guard $0.count == 2 else {

From b199064b94c994a0c80b178863b2e3c17f668184 Mon Sep 17 00:00:00 2001
From: Davide De Rosa <keeshux@gmail.com>
Date: Wed, 17 Apr 2019 00:45:08 +0200
Subject: [PATCH 2/3] Only override domain if non-nil

---
 TunnelKit/Sources/AppExtension/TunnelKitProvider.swift | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
index 6152ac8..c9b8142 100644
--- a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
+++ b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
@@ -564,10 +564,9 @@ extension TunnelKitProvider: SessionProxyDelegate {
         if dnsServers?.isEmpty ?? true {
             dnsServers = reply.options.dnsServers
         }
-        let searchDomain = cfg.sessionConfiguration.searchDomain ?? reply.options.searchDomain
         let dnsSettings = NEDNSSettings(servers: dnsServers ?? [])
-        dnsSettings.domainName = searchDomain
-        if let searchDomain = searchDomain {
+        if let searchDomain = cfg.sessionConfiguration.searchDomain ?? reply.options.searchDomain {
+            dnsSettings.domainName = searchDomain
             dnsSettings.searchDomains = [searchDomain]
         }
         

From 233aa02169ba59a72edac18310838bd1049dcb63 Mon Sep 17 00:00:00 2001
From: Davide De Rosa <keeshux@gmail.com>
Date: Wed, 17 Apr 2019 00:46:34 +0200
Subject: [PATCH 3/3] Add FIXME for default DNS from network interface

---
 TunnelKit/Sources/AppExtension/TunnelKitProvider.swift | 1 +
 1 file changed, 1 insertion(+)

diff --git a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
index c9b8142..5f2ae7e 100644
--- a/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
+++ b/TunnelKit/Sources/AppExtension/TunnelKitProvider.swift
@@ -564,6 +564,7 @@ extension TunnelKitProvider: SessionProxyDelegate {
         if dnsServers?.isEmpty ?? true {
             dnsServers = reply.options.dnsServers
         }
+        // FIXME: default to DNS servers from current network instead
         let dnsSettings = NEDNSSettings(servers: dnsServers ?? [])
         if let searchDomain = cfg.sessionConfiguration.searchDomain ?? reply.options.searchDomain {
             dnsSettings.domainName = searchDomain