Deal with some xcode warnings (#216)

This performs the recommended setting updates from xcode, though I needed to turn off `ENABLE_USER_SCRIPT_SANDBOXING` as it does not seem to be fully compatible with flutter.

I also dealt with a warning of: "Extension declares a conformance of imported type 'String' to imported protocol 'Error'; this will not behave correctly if the owners of 'Swift' introduce this conformance in the future", by creating and using some custom error types.

Lastly, I fixed our podfile to ensure that the `IPHONEOS_DEPLOYMENT_TARGET` is at least 12, which is our project setting.

ios/NebulaNetworkExtension/PacketTunnelProvider.swift

@@ -10,6 +10,20 @@ enum VPNStartError: Error {
     case noProviderConfig
 }
 
+enum AppMessageError: Error {
+    case unknownIPCType(command: String)
+}
+
+extension AppMessageError: LocalizedError {
+    public var description: String? {
+        switch self {
+        case .unknownIPCType(let command):
+            return NSLocalizedString("Unknown IPC message type \(String(command))", comment: "")
+        }
+    }
+}
+
+
 class PacketTunnelProvider: NEPacketTunnelProvider {
     private var networkMonitor: NWPathMonitor?
     
@@ -221,7 +235,7 @@ class PacketTunnelProvider: NEPacketTunnelProvider {
         case "closeTunnel": (data, error) = closeTunnel(args: call.arguments!)
             
         default:
-            error = "Unknown IPC message type \(call.command)"
+            error = AppMessageError.unknownIPCType(command: call.command)
         }
         
         if (error != nil) {

ios/NebulaNetworkExtension/Site.swift

@@ -5,7 +5,41 @@ import os.log
 
 let log = Logger(subsystem: "net.defined.mobileNebula", category: "Site")
 
-extension String: Error {}
+enum SiteError: Error {
+    case nonConforming(site: [String : Any]?)
+    case noCertificate
+    case keyLoad
+    case keySave
+    case unmanagedGetCredentials
+    case dnCredentialLoad
+    case dnCredentialSave
+
+    // Throw in all other cases
+    case unexpected(code: Int)
+}
+
+extension SiteError: CustomStringConvertible {
+    public var description: String {
+        switch self {
+        case .nonConforming(let site):
+            return String("Non-conforming site \(String(describing: site))")
+        case .noCertificate:
+            return "No certificate found"
+        case .keyLoad:
+            return "failed to get key from keychain"
+        case .keySave:
+            return "failed to store key material in keychain"
+        case .unmanagedGetCredentials:
+            return "Cannot get dn credentials for unmanaged site"
+        case .dnCredentialLoad:
+            return "failed to find dn credentials in keychain"
+        case .dnCredentialSave:
+            return "failed to store dn credentials in keychain"
+        case .unexpected(_):
+            return "An unexpected error occurred."
+        }
+    }
+}
 
 enum IPCResponseType: String, Codable {
     case error = "error"
@@ -174,7 +208,7 @@ class Site: Codable {
 
         let id = dict?["id"] as? String ?? nil
         if id == nil {
-            throw("Non-conforming site \(String(describing: dict))")
+            throw SiteError.nonConforming(site: dict)
         }
 
         try self.init(path: SiteList.getSiteConfigFile(id: id!, createDir: false))
@@ -218,7 +252,7 @@ class Site: Codable {
 
             certs = try JSONDecoder().decode([CertificateInfo].self, from: rawDetails.data(using: .utf8)!)
             if (certs.count == 0) {
-                throw "No certificate found"
+                throw SiteError.noCertificate
             }
             cert = certs[0]
             if (!cert!.validity.valid) {
@@ -285,7 +319,7 @@ class Site: Codable {
     // Gets the private key from the keystore, we don't always need it in memory
     func getKey() throws -> String {
         guard let keyData = KeyChain.load(key: "\(id).key") else {
-            throw "failed to get key from keychain"
+            throw SiteError.keyLoad
         }
 
         //TODO: make sure this is valid on return!
@@ -294,12 +328,12 @@ class Site: Codable {
 
     func getDNCredentials() throws -> DNCredentials {
         if (!managed) {
-            throw "unmanaged site has no dn credentials"
+            throw SiteError.unmanagedGetCredentials
         }
 
         let rawDNCredentials = KeyChain.load(key: "\(id).dnCredentials")
         if rawDNCredentials == nil {
-            throw "failed to find dn credentials in keychain"
+            throw SiteError.dnCredentialLoad
         }
 
         let decoder = JSONDecoder()
@@ -311,7 +345,7 @@ class Site: Codable {
         creds.invalid = true
 
         if (!(try creds.save(siteID: self.id))) {
-            throw "failed to store dn credentials in keychain"
+            throw SiteError.dnCredentialLoad
         }
     }
 
@@ -320,7 +354,7 @@ class Site: Codable {
         creds.invalid = false
 
         if (!(try creds.save(siteID: self.id))) {
-            throw "failed to store dn credentials in keychain"
+            throw SiteError.dnCredentialSave
         }
     }
 
@@ -438,13 +472,13 @@ struct IncomingSite: Codable {
             if (self.key != nil) {
                 let data = self.key!.data(using: .utf8)
                 if (!KeyChain.save(key: "\(self.id).key", data: data!, managed: self.managed ?? false)) {
-                    return callback("failed to store key material in keychain")
+                    return callback(SiteError.keySave)
                 }
             }
 
             do {
                 if ((try self.dnCredentials?.save(siteID: self.id)) == false) {
-                    return callback("failed to store dn credentials in keychain")
+                    return callback(SiteError.dnCredentialSave)
                 }
             } catch {
                 return callback(error)

ios/Podfile

@@ -47,7 +47,7 @@ post_install do |installer|
   installer.generated_projects.each do |project|
     project.targets.each do |target|
       target.build_configurations.each do |config|
-        if Gem::Version.new('11.0') > Gem::Version.new(config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'])
+        if Gem::Version.new('12.0') > Gem::Version.new(config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'])
           config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '12.0'
         end
       end

ios/Podfile.lock

@@ -67,6 +67,6 @@ SPEC CHECKSUMS:
   SwiftyJSON: f5b1bf1cd8dd53cd25887ac0eabcfd92301c6a5a
   url_launcher_ios: 5334b05cef931de560670eeae103fd3e431ac3fe
 
-PODFILE CHECKSUM: 6c27958b72564ad432c3d7024daffcc9edb8534a
+PODFILE CHECKSUM: b44d9de9944d89118a4ff4bfffe1c2dab91de156
 
 COCOAPODS: 1.15.2

ios/Runner.xcodeproj/project.pbxproj

@@ -20,7 +20,7 @@
 		43871C9D2444E2EC004F9075 /* Sites.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43871C9C2444E2EC004F9075 /* Sites.swift */; };
 		43AA894F2444D8BC00EDC39C /* NetworkExtension.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 43AA894E2444D8BC00EDC39C /* NetworkExtension.framework */; };
 		43AA89572444DA6500EDC39C /* PacketTunnelProvider.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43AA89562444DA6500EDC39C /* PacketTunnelProvider.swift */; };
-		43AA895C2444DA6500EDC39C /* NebulaNetworkExtension.appex in Embed App Extensions */ = {isa = PBXBuildFile; fileRef = 43AA89542444DA6500EDC39C /* NebulaNetworkExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
+		43AA895C2444DA6500EDC39C /* NebulaNetworkExtension.appex in Embed Foundation Extensions */ = {isa = PBXBuildFile; fileRef = 43AA89542444DA6500EDC39C /* NebulaNetworkExtension.appex */; settings = {ATTRIBUTES = (RemoveHeadersOnCopy, ); }; };
 		43AA89622444DAA500EDC39C /* NetworkExtension.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 43AA894E2444D8BC00EDC39C /* NetworkExtension.framework */; };
 		43ED87842912D0DD004DAFC5 /* DNUpdate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43ED87832912D0DD004DAFC5 /* DNUpdate.swift */; };
 		43ED87852912D0DD004DAFC5 /* DNUpdate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 43ED87832912D0DD004DAFC5 /* DNUpdate.swift */; };
@@ -47,15 +47,15 @@
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXCopyFilesBuildPhase section */
-		43AA89612444DA6500EDC39C /* Embed App Extensions */ = {
+		43AA89612444DA6500EDC39C /* Embed Foundation Extensions */ = {
 			isa = PBXCopyFilesBuildPhase;
 			buildActionMask = 2147483647;
 			dstPath = "";
 			dstSubfolderSpec = 13;
 			files = (
-				43AA895C2444DA6500EDC39C /* NebulaNetworkExtension.appex in Embed App Extensions */,
+				43AA895C2444DA6500EDC39C /* NebulaNetworkExtension.appex in Embed Foundation Extensions */,
 			);
-			name = "Embed App Extensions";
+			name = "Embed Foundation Extensions";
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 		9705A1C41CF9048500538489 /* Embed Frameworks */ = {
@@ -266,7 +266,7 @@
 				97C146EB1CF9000F007C117D /* Frameworks */,
 				97C146EC1CF9000F007C117D /* Resources */,
 				9705A1C41CF9048500538489 /* Embed Frameworks */,
-				43AA89612444DA6500EDC39C /* Embed App Extensions */,
+				43AA89612444DA6500EDC39C /* Embed Foundation Extensions */,
 				00C7A79AE88792090BDAC68B /* [CP] Embed Pods Frameworks */,
 				3B06AD1E1E4923F5004D2608 /* Thin Binary */,
 			);
@@ -286,8 +286,9 @@
 		97C146E61CF9000F007C117D /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
+				BuildIndependentTargetsInParallel = YES;
 				LastSwiftUpdateCheck = 1140;
-				LastUpgradeCheck = 1510;
+				LastUpgradeCheck = 1600;
 				ORGANIZATIONNAME = "The Chromium Authors";
 				TargetAttributes = {
 					43AA89532444DA6500EDC39C = {
@@ -538,6 +539,7 @@
 				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
 				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
 				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
@@ -548,6 +550,7 @@
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				ENABLE_NS_ASSERTIONS = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_USER_SCRIPT_SANDBOXING = NO;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
@@ -569,7 +572,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_ENTITLEMENTS = Runner/Runner.entitlements;
@@ -740,6 +742,7 @@
 				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
 				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
 				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
@@ -750,6 +753,7 @@
 				DEBUG_INFORMATION_FORMAT = dwarf;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				ENABLE_TESTABILITY = YES;
+				ENABLE_USER_SCRIPT_SANDBOXING = NO;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
 				GCC_NO_COMMON_BLOCKS = YES;
@@ -795,6 +799,7 @@
 				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
 				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
 				CLANG_WARN_STRICT_PROTOTYPES = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
@@ -805,6 +810,7 @@
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				ENABLE_NS_ASSERTIONS = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_USER_SCRIPT_SANDBOXING = NO;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_NO_COMMON_BLOCKS = YES;
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
@@ -817,6 +823,7 @@
 				MTL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				SUPPORTED_PLATFORMS = iphoneos;
+				SWIFT_COMPILATION_MODE = wholemodule;
 				SWIFT_OPTIMIZATION_LEVEL = "-Owholemodule";
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VALIDATE_PRODUCT = YES;
@@ -827,7 +834,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 9740EEB21CF90195004384FC /* Debug.xcconfig */;
 			buildSettings = {
-				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_ENTITLEMENTS = Runner/Runner.entitlements;
@@ -863,7 +869,6 @@
 			isa = XCBuildConfiguration;
 			baseConfigurationReference = 7AFA3C8E1D35360C0083082E /* Release.xcconfig */;
 			buildSettings = {
-				ALWAYS_EMBED_SWIFT_STANDARD_LIBRARIES = YES;
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_ENTITLEMENTS = Runner/Runner.entitlements;

ios/Runner.xcodeproj/xcshareddata/xcschemes/Runner.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1510"
+   LastUpgradeVersion = "1600"
    version = "1.7">
    <BuildAction
       parallelizeBuildables = "YES"