Add options to explicitly enable/disable DNS/proxy

DNS/proxy settings, when missing from configuration, fall back to
whatever the server pushes.

With isDNSEnabled/isProxyEnabled it's now possible to override this
behavior.

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - OpenVPN: Parse authentication requirement from `--auth-user-pass`.
 - OpenVPN: Handle multiple `--remote` options correctly.
+- OpenVPN: Explicitly enable/disable DNS/proxy settings.
 
 ### Changed
 

Sources/TunnelKitOpenVPNAppExtension/OpenVPNTunnelProvider.swift

@@ -644,8 +644,9 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
             return
         }
         
-        var dnsServers: [String] = []
         var dnsSettings: NEDNSSettings?
+        if cfg.configuration.isDNSEnabled ?? true {
+            var dnsServers: [String] = []
             if #available(iOS 14, macOS 11, *) {
                 switch cfg.configuration.dnsProtocol {
                 case .https:
@@ -721,8 +722,10 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
                     }
                 }
             }
+        }
         
         var proxySettings: NEProxySettings?
+        if cfg.configuration.isProxyEnabled ?? true {
             if let httpsProxy = cfg.configuration.httpsProxy ?? options.httpsProxy {
                 proxySettings = NEProxySettings()
                 proxySettings?.httpsServer = httpsProxy.neProxy()
@@ -751,6 +754,7 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
                 proxySettings?.exceptionList = bypass
                 log.info("Routing: Setting proxy by-pass list: \(bypass.maskedDescription)")
             }
+        }
 
         // block LAN if desired
         if routingPolicies?.contains(.blockLocal) ?? false {

Sources/TunnelKitOpenVPNCore/Configuration.swift

@@ -252,6 +252,9 @@ extension OpenVPN {
         /// The settings for IPv6. `OpenVPNSession` only evaluates this server-side.
         public var ipv6: IPv6Settings?
         
+        /// Set false to ignore DNS settings, even when pushed.
+        public var isDNSEnabled: Bool?
+        
         /// The DNS protocol, defaults to `.plain` (iOS 14+ / macOS 11+).
         public var dnsProtocol: DNSProtocol?
 
@@ -282,6 +285,9 @@ extension OpenVPN {
         /// The Proxy Auto-Configuration (PAC) url.
         public var proxyAutoConfigurationURL: URL?
         
+        /// Set false to ignore proxy settings, even when pushed.
+        public var isProxyEnabled: Bool?
+        
         /// The HTTP proxy.
         public var httpProxy: Proxy?
 
@@ -341,11 +347,13 @@ extension OpenVPN {
                 peerId: peerId,
                 ipv4: ipv4,
                 ipv6: ipv6,
+                isDNSEnabled: isDNSEnabled,
                 dnsProtocol: dnsProtocol,
                 dnsServers: dnsServers,
                 dnsHTTPSURL: dnsHTTPSURL,
                 dnsTLSServerName: dnsTLSServerName,
                 searchDomains: searchDomains,
+                isProxyEnabled: isProxyEnabled,
                 httpProxy: httpProxy,
                 httpsProxy: httpsProxy,
                 proxyAutoConfigurationURL: proxyAutoConfigurationURL,
@@ -436,6 +444,9 @@ extension OpenVPN {
         /// - Seealso: `ConfigurationBuilder.ipv6`
         public let ipv6: IPv6Settings?
 
+        /// - Seealso: `ConfigurationBuilder.isDNSEnabled`
+        public let isDNSEnabled: Bool?
+
         /// - Seealso: `ConfigurationBuilder.dnsProtocol`
         public let dnsProtocol: DNSProtocol?
         
@@ -451,6 +462,9 @@ extension OpenVPN {
         /// - Seealso: `ConfigurationBuilder.searchDomains`
         public let searchDomains: [String]?
 
+        /// - Seealso: `ConfigurationBuilder.isProxyEnabled`
+        public let isProxyEnabled: Bool?
+
         /// - Seealso: `ConfigurationBuilder.httpProxy`
         public let httpProxy: Proxy?
 
@@ -519,11 +533,13 @@ extension OpenVPN.Configuration {
         builder.peerId = peerId
         builder.ipv4 = ipv4
         builder.ipv6 = ipv6
+        builder.isDNSEnabled = isDNSEnabled
         builder.dnsProtocol = dnsProtocol
         builder.dnsServers = dnsServers
         builder.dnsHTTPSURL = dnsHTTPSURL
         builder.dnsTLSServerName = dnsTLSServerName
         builder.searchDomains = searchDomains
+        builder.isProxyEnabled = isProxyEnabled
         builder.httpProxy = httpProxy
         builder.httpsProxy = httpsProxy
         builder.proxyAutoConfigurationURL = proxyAutoConfigurationURL