Merge pull request #125 from ThinkChaos/proxy_auto_conf

Add Proxy Auto-Configuration (PAC) support

TunnelKit/Sources/Protocols/OpenVPN/AppExtension/OpenVPNTunnelProvider+Configuration.swift

@@ -183,6 +183,8 @@ extension OpenVPNTunnelProvider {
             
             static let httpsProxy = "HTTPSProxy"
             
+            static let proxyAutoConfigurationURL = "ProxyAutoConfigurationURL"
+            
             static let proxyBypassDomains = "ProxyBypassDomains"
             
             static let routingPolicies = "RoutingPolicies"
@@ -603,6 +605,9 @@ private extension OpenVPN.Configuration {
         if let httpsProxy = httpsProxy {
             dict[S.httpsProxy] = httpsProxy.rawValue
         }
+        if let proxyAutoConfigurationURL = proxyAutoConfigurationURL {
+            dict[S.proxyAutoConfigurationURL] = proxyAutoConfigurationURL.absoluteString
+        }
         if let proxyBypassDomains = proxyBypassDomains {
             dict[S.proxyBypassDomains] = proxyBypassDomains
         }
@@ -681,6 +686,9 @@ private extension OpenVPN.Configuration {
         if let httpsProxy = httpsProxy {
             log.info("\tHTTPS proxy: \(httpsProxy.maskedDescription)")
         }
+        if let proxyAutoConfigurationURL = proxyAutoConfigurationURL {
+            log.info("\tPAC: \(proxyAutoConfigurationURL)")
+        }
         if let proxyBypassDomains = proxyBypassDomains {
             log.info("\tProxy bypass domains: \(proxyBypassDomains.maskedDescription)")
         }

TunnelKit/Sources/Protocols/OpenVPN/AppExtension/OpenVPNTunnelProvider.swift

@@ -514,6 +514,9 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
             if let proxy = options.httpsProxy {
                 log.info("\t\tHTTPS: \(proxy.maskedDescription)")
             }
+            if let pacURL = options.proxyAutoConfigurationURL {
+                log.info("\t\tPAC: \(pacURL)")
+            }
             if let bypass = options.proxyBypassDomains {
                 log.info("\t\tBypass domains: \(bypass.maskedDescription)")
             }
@@ -677,6 +680,14 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
             proxySettings?.httpEnabled = true
             log.info("Routing: Setting HTTP proxy \(httpProxy.address.maskedDescription):\(httpProxy.port)")
         }
+        if let pacURL = cfg.sessionConfiguration.proxyAutoConfigurationURL ?? options.proxyAutoConfigurationURL {
+            if proxySettings == nil {
+                proxySettings = NEProxySettings()
+            }
+            proxySettings?.proxyAutoConfigurationURL = pacURL
+            proxySettings?.autoProxyConfigurationEnabled = true
+            log.info("Routing: Setting PAC \(pacURL)")
+        }
 
         // only set if there is a proxy (proxySettings set to non-nil above)
         if let bypass = cfg.sessionConfiguration.proxyBypassDomains ?? options.proxyBypassDomains {

TunnelKit/Sources/Protocols/OpenVPN/Configuration.swift

@@ -247,6 +247,9 @@ extension OpenVPN {
         /// The search domain.
         public var searchDomain: String?
 
+        /// The Proxy Auto-Configuration (PAC) url.
+        public var proxyAutoConfigurationURL: URL?
+        
         /// The HTTP proxy.
         public var httpProxy: Proxy?
 
@@ -295,6 +298,7 @@ extension OpenVPN {
                 searchDomain: searchDomain,
                 httpProxy: httpProxy,
                 httpsProxy: httpsProxy,
+                proxyAutoConfigurationURL: proxyAutoConfigurationURL,
                 proxyBypassDomains: proxyBypassDomains,
                 routingPolicies: routingPolicies
             )
@@ -396,6 +400,9 @@ extension OpenVPN {
         /// - Seealso: `ConfigurationBuilder.httpsProxy`
         public let httpsProxy: Proxy?
         
+        /// - Seealso: `ConfigurationBuilder.proxyAutoConfigurationURL`
+        public let proxyAutoConfigurationURL: URL?
+
         /// - Seealso: `ConfigurationBuilder.proxyBypassDomains`
         public let proxyBypassDomains: [String]?
         
@@ -457,6 +464,7 @@ extension OpenVPN.Configuration {
         builder.searchDomain = searchDomain
         builder.httpProxy = httpProxy
         builder.httpsProxy = httpsProxy
+        builder.proxyAutoConfigurationURL = proxyAutoConfigurationURL
         builder.proxyBypassDomains = proxyBypassDomains
         builder.routingPolicies = routingPolicies
         return builder

TunnelKit/Sources/Protocols/OpenVPN/ConfigurationParser.swift

@@ -96,7 +96,7 @@ extension OpenVPN {
             
             static let domain = NSRegularExpression("^dhcp-option +DOMAIN +[^ ]+")
             
-            static let proxy = NSRegularExpression("^dhcp-option +PROXY_(HTTPS?) +[^ ]+ +\\d+")
+            static let proxy = NSRegularExpression("^dhcp-option +PROXY_(HTTPS? +[^ ]+ +\\d+|AUTO_CONFIG_URL +[^ ]+)")
             
             static let proxyBypass = NSRegularExpression("^dhcp-option +PROXY_BYPASS +.+")
             
@@ -228,6 +228,7 @@ extension OpenVPN {
             var optSearchDomain: String?
             var optHTTPProxy: Proxy?
             var optHTTPSProxy: Proxy?
+            var optProxyAutoConfigurationURL: URL?
             var optProxyBypass: [String]?
             var optRedirectGateway: Set<RedirectGateway>?
 
@@ -533,6 +534,15 @@ extension OpenVPN {
                     optSearchDomain = $0[1]
                 }
                 Regex.proxy.enumerateArguments(in: line) {
+                    if $0.count == 2 {
+                        guard let url = URL(string: $0[1]) else {
+                            unsupportedError = ConfigurationError.malformed(option: "dhcp-option PROXY_AUTO_CONFIG_URL has malformed URL")
+                            return
+                        }
+                        optProxyAutoConfigurationURL = url
+                        return
+                    }
+
                     guard $0.count == 3, let port = UInt16($0[2]) else {
                         return
                     }
@@ -731,6 +741,7 @@ extension OpenVPN {
             sessionBuilder.searchDomain = optSearchDomain
             sessionBuilder.httpProxy = optHTTPProxy
             sessionBuilder.httpsProxy = optHTTPSProxy
+            sessionBuilder.proxyAutoConfigurationURL = optProxyAutoConfigurationURL
             sessionBuilder.proxyBypassDomains = optProxyBypass
 
             if let flags = optRedirectGateway {

TunnelKitTests/OpenVPN/ConfigurationParserTests.swift

@@ -56,6 +56,7 @@ class ConfigurationParserTests: XCTestCase {
             "dhcp-option DOMAIN example.com",
             "dhcp-option PROXY_HTTP 1.2.3.4 8081",
             "dhcp-option PROXY_HTTPS 7.8.9.10 8082",
+            "dhcp-option PROXY_AUTO_CONFIG_URL https://pac/",
             "dhcp-option PROXY_BYPASS   foo.com   bar.org     net.chat"
         ]
         XCTAssertNoThrow(try OpenVPN.ConfigurationParser.parsed(fromLines: lines))
@@ -67,6 +68,7 @@ class ConfigurationParserTests: XCTestCase {
         XCTAssertEqual(parsed.httpProxy?.port, 8081)
         XCTAssertEqual(parsed.httpsProxy?.address, "7.8.9.10")
         XCTAssertEqual(parsed.httpsProxy?.port, 8082)
+        XCTAssertEqual(parsed.proxyAutoConfigurationURL?.absoluteString, "https://pac/")
         XCTAssertEqual(parsed.proxyBypassDomains, ["foo.com", "bar.org", "net.chat"])
     }