Hide errors behind façade TunnelKit*Error (#325)

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Changed
+
+- Hide errors behind façade TunnelKit\*Error. [#325](https://github.com/passepartoutvpn/tunnelkit/pull/325)
+
 ## 6.0.0 (2023-04-02)
 
 ### Added

Sources/TunnelKitCore/DNSResolver.swift

@@ -53,8 +53,11 @@ public struct DNSRecord {
 
 /// Errors coming from `DNSResolver`.
 public enum DNSError: Error {
+
+    /// Resolution failed.
     case failure
 
+    /// Resolution timed out.
     case timeout
 }
 
@@ -71,8 +74,8 @@ public class DNSResolver {
      - Parameter queue: The queue to execute the `completionHandler` in.
      - Parameter completionHandler: The completion handler with the resolved addresses and an optional error.
      */
-    public static func resolve(_ hostname: String, timeout: Int, queue: DispatchQueue, completionHandler: @escaping (Result<[DNSRecord], DNSError>) -> Void) {
+    public static func resolve(_ hostname: String, timeout: Int, queue: DispatchQueue, completionHandler: @escaping (Result<[DNSRecord], Error>) -> Void) {
-        var pendingHandler: ((Result<[DNSRecord], DNSError>) -> Void)? = completionHandler
+        var pendingHandler: ((Result<[DNSRecord], Error>) -> Void)? = completionHandler
         let host = CFHostCreateWithName(nil, hostname as CFString).takeRetainedValue()
         DNSResolver.queue.async {
             CFHostStartInfoResolution(host, .addresses, nil)
@@ -91,15 +94,15 @@ public class DNSResolver {
                 return
             }
             CFHostCancelInfoResolution(host, .addresses)
-            handler(.failure(.timeout))
+            handler(.failure(TunnelKitCoreError.dnsResolver(.timeout)))
             pendingHandler = nil
         }
     }
 
-    private static func didResolve(host: CFHost, completionHandler: @escaping (Result<[DNSRecord], DNSError>) -> Void) {
+    private static func didResolve(host: CFHost, completionHandler: @escaping (Result<[DNSRecord], Error>) -> Void) {
         var success: DarwinBoolean = false
         guard let rawAddresses = CFHostGetAddressing(host, &success)?.takeUnretainedValue() as Array? else {
-            completionHandler(.failure(.failure))
+            completionHandler(.failure(TunnelKitCoreError.dnsResolver(.failure)))
             return
         }
 
@@ -129,7 +132,7 @@ public class DNSResolver {
             }
         }
         guard !records.isEmpty else {
-            completionHandler(.failure(.failure))
+            completionHandler(.failure(TunnelKitCoreError.dnsResolver(.failure)))
             return
         }
         completionHandler(.success(records))

Sources/TunnelKitCore/IPv4Settings.swift

@@ -62,23 +62,10 @@ public struct IPv4Settings: Codable, Equatable, CustomStringConvertible {
     /// The address of the default gateway.
     public let defaultGateway: String
 
-    /// The additional routes.
-    @available(*, deprecated, message: "Store routes separately")
-    public let routes: [Route]
-
     public init(address: String, addressMask: String, defaultGateway: String) {
         self.address = address
         self.addressMask = addressMask
         self.defaultGateway = defaultGateway
-        self.routes = []
-    }
-
-    @available(*, deprecated, message: "Store routes separately")
-    public init(address: String, addressMask: String, defaultGateway: String, routes: [Route]) {
-        self.address = address
-        self.addressMask = addressMask
-        self.defaultGateway = defaultGateway
-        self.routes = routes
     }
 
     // MARK: CustomStringConvertible

Sources/TunnelKitCore/IPv6Settings.swift

@@ -62,23 +62,10 @@ public struct IPv6Settings: Codable, Equatable, CustomStringConvertible {
     /// The address of the default gateway.
     public let defaultGateway: String
 
-    /// The additional routes.
-    @available(*, deprecated, message: "Store routes separately")
-    public let routes: [Route]
-
     public init(address: String, addressPrefixLength: UInt8, defaultGateway: String) {
         self.address = address
         self.addressPrefixLength = addressPrefixLength
         self.defaultGateway = defaultGateway
-        self.routes = []
-    }
-
-    @available(*, deprecated, message: "Store routes separately")
-    public init(address: String, addressPrefixLength: UInt8, defaultGateway: String, routes: [Route]) {
-        self.address = address
-        self.addressPrefixLength = addressPrefixLength
-        self.defaultGateway = defaultGateway
-        self.routes = routes
     }
 
     // MARK: CustomStringConvertible

Sources/TunnelKitCore/SecureRandom.swift

@@ -54,7 +54,7 @@ public class SecureRandom {
         var randomBuffer = [UInt8](repeating: 0, count: 4)
 
         guard SecRandomCopyBytes(kSecRandomDefault, 4, &randomBuffer) == 0 else {
-            throw SecureRandomError.randomGenerator
+            throw TunnelKitCoreError.secureRandom(.randomGenerator)
         }
 
         var randomNumber: UInt32 = 0
@@ -71,7 +71,7 @@ public class SecureRandom {
         try withUnsafeMutablePointer(to: &randomNumber) {
             try $0.withMemoryRebound(to: UInt8.self, capacity: 4) { (randomBytes: UnsafeMutablePointer<UInt8>) -> Void in
                 guard SecRandomCopyBytes(kSecRandomDefault, 4, randomBytes) == 0 else {
-                    throw SecureRandomError.randomGenerator
+                    throw TunnelKitCoreError.secureRandom(.randomGenerator)
                 }
             }
         }
@@ -85,7 +85,7 @@ public class SecureRandom {
         try randomData.withUnsafeMutableBytes {
             let randomBytes = $0.bytePointer
             guard SecRandomCopyBytes(kSecRandomDefault, length, randomBytes) == 0 else {
-                throw SecureRandomError.randomGenerator
+                throw TunnelKitCoreError.secureRandom(.randomGenerator)
             }
         }
 
@@ -101,7 +101,7 @@ public class SecureRandom {
         }
 
         guard SecRandomCopyBytes(kSecRandomDefault, length, randomBytes) == 0 else {
-            throw SecureRandomError.randomGenerator
+            throw TunnelKitCoreError.secureRandom(.randomGenerator)
         }
 
         return Z(bytes: randomBytes, count: length)

Sources/TunnelKitCore/TunnelKitCoreError.swift

@@ -1,8 +1,8 @@
 //
-//  Errors.swift
+//  TunnelKitCoreError.swift
 //  TunnelKit
 //
-//  Created by Davide De Rosa on 5/19/19.
+//  Created by Davide De Rosa on 6/16/23.
 //  Copyright (c) 2023 Davide De Rosa. All rights reserved.
 //
 //  https://github.com/passepartoutvpn
@@ -24,19 +24,10 @@
 //
 
 import Foundation
-import CTunnelKitOpenVPNCore
 
-extension Error {
+/// Errors returned by Core library.
-    public func isOpenVPNError() -> Bool {
+public enum TunnelKitCoreError: Error {
-        let te = self as NSError
+    case secureRandom(_ error: SecureRandomError)
-        return te.domain == OpenVPNErrorDomain
-    }
 
-    public func openVPNErrorCode() -> OpenVPNErrorCode? {
+    case dnsResolver(_ error: DNSError)
-        let te = self as NSError
-        guard te.domain == OpenVPNErrorDomain else {
-            return nil
-        }
-        return OpenVPNErrorCode(rawValue: te.code)
-    }
 }

Sources/TunnelKitManager/Keychain.swift

@@ -92,11 +92,11 @@ public class Keychain {
                 return try passwordReference(for: username, context: context)
             }
             removePassword(for: username, context: context)
-        } catch let e as KeychainError {
+        } catch let error as KeychainError {
 
             // rethrow cancelation
-            if e == .userCancelled {
+            if error == .userCancelled {
-                throw e
+                throw error
             }
 
             // otherwise, no pre-existing password
@@ -114,7 +114,7 @@ public class Keychain {
         var ref: CFTypeRef?
         let status = SecItemAdd(query as CFDictionary, &ref)
         guard status == errSecSuccess, let refData = ref as? Data else {
-            throw KeychainError.add
+            throw TunnelKitManagerError.keychain(.add)
         }
         return refData
     }
@@ -160,16 +160,16 @@ public class Keychain {
             break
 
         case errSecUserCanceled:
-            throw KeychainError.userCancelled
+            throw TunnelKitManagerError.keychain(.userCancelled)
 
         default:
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         guard let data = result as? Data else {
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         guard let password = String(data: data, encoding: .utf8) else {
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         return password
     }
@@ -197,13 +197,13 @@ public class Keychain {
             break
 
         case errSecUserCanceled:
-            throw KeychainError.userCancelled
+            throw TunnelKitManagerError.keychain(.userCancelled)
 
         default:
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         guard let data = result as? Data else {
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         return data
     }
@@ -226,16 +226,16 @@ public class Keychain {
             break
 
         case errSecUserCanceled:
-            throw KeychainError.userCancelled
+            throw TunnelKitManagerError.keychain(.userCancelled)
 
         default:
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         guard let data = result as? Data else {
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         guard let password = String(data: data, encoding: .utf8) else {
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
         return password
     }
@@ -265,7 +265,7 @@ public class Keychain {
 
         let status = SecItemAdd(query as CFDictionary, nil)
         guard status == errSecSuccess else {
-            throw KeychainError.add
+            throw TunnelKitManagerError.keychain(.add)
         }
         return try publicKey(withIdentifier: identifier)
     }
@@ -294,13 +294,13 @@ public class Keychain {
             break
 
         case errSecUserCanceled:
-            throw KeychainError.userCancelled
+            throw TunnelKitManagerError.keychain(.userCancelled)
 
         default:
-            throw KeychainError.notFound
+            throw TunnelKitManagerError.keychain(.notFound)
         }
 //        guard let key = result as? SecKey else {
-//            throw KeychainError.typeMismatch
+//            throw TunnelKitManagerError.keychain(.typeMismatch)
 //        }
 //        return key
         return result as! SecKey

Sources/TunnelKitManager/TunnelKitManagerError.swift

@@ -0,0 +1,31 @@
+//
+//  TunnelKitManagerError.swift
+//  TunnelKit
+//
+//  Created by Davide De Rosa on 6/16/23.
+//  Copyright (c) 2023 Davide De Rosa. All rights reserved.
+//
+//  https://github.com/passepartoutvpn
+//
+//  This file is part of TunnelKit.
+//
+//  TunnelKit is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  TunnelKit is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with TunnelKit.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+import Foundation
+
+/// Errors returned by Core library.
+public enum TunnelKitManagerError: Error {
+    case keychain(_ error: KeychainError)
+}

Sources/TunnelKitOpenVPNAppExtension/ConnectionStrategy.swift

@@ -94,7 +94,7 @@ class ConnectionStrategy {
         from provider: NEProvider,
         timeout: Int,
         queue: DispatchQueue,
-        completionHandler: @escaping (Result<GenericSocket, OpenVPNProviderError>) -> Void) {
+        completionHandler: @escaping (Result<GenericSocket, TunnelKitOpenVPNError>) -> Void) {
         guard let remote = currentRemote else {
             completionHandler(.failure(.exhaustedEndpoints))
             return

Sources/TunnelKitOpenVPNAppExtension/OpenVPNTunnelProvider.swift

@@ -145,28 +145,28 @@ open class OpenVPNTunnelProvider: NEPacketTunnelProvider {
         // required configuration
         do {
             guard let tunnelProtocol = protocolConfiguration as? NETunnelProviderProtocol else {
-                throw OpenVPNProviderConfigurationError.parameter(name: "protocolConfiguration")
+                throw ConfigurationError.parameter(name: "protocolConfiguration")
             }
             guard let _ = tunnelProtocol.serverAddress else {
-                throw OpenVPNProviderConfigurationError.parameter(name: "protocolConfiguration.serverAddress")
+                throw ConfigurationError.parameter(name: "protocolConfiguration.serverAddress")
             }
             guard let providerConfiguration = tunnelProtocol.providerConfiguration else {
-                throw OpenVPNProviderConfigurationError.parameter(name: "protocolConfiguration.providerConfiguration")
+                throw ConfigurationError.parameter(name: "protocolConfiguration.providerConfiguration")
             }
             cfg = try fromDictionary(OpenVPN.ProviderConfiguration.self, providerConfiguration)
-        } catch let e {
+        } catch let cfgError as ConfigurationError {
-            var message: String?
+            switch cfgError {
-            if let te = e as? OpenVPNProviderConfigurationError {
-                switch te {
             case .parameter(let name):
-                    message = "Tunnel configuration incomplete: \(name)"
+                NSLog("Tunnel configuration incomplete: \(name)")
 
             default:
-                    break
+                NSLog("Tunnel configuration error: \(cfgError)")
             }
-            }
+            completionHandler(cfgError)
-            NSLog(message ?? "Unexpected error in tunnel configuration: \(e)")
+            return
-            completionHandler(e)
+        } catch {
+            NSLog("Unexpected error in tunnel configuration: \(error)")
+            completionHandler(error)
             return
         }
 
@@ -188,7 +188,7 @@ open class OpenVPNTunnelProvider: NEPacketTunnelProvider {
         let credentials: OpenVPN.Credentials?
         if let username = protocolConfiguration.username, let passwordReference = protocolConfiguration.passwordReference {
             guard let password = try? Keychain.password(forReference: passwordReference) else {
-                completionHandler(OpenVPNProviderConfigurationError.credentials(details: "Keychain.password(forReference:)"))
+                completionHandler(ConfigurationError.credentials(details: "Keychain.password(forReference:)"))
                 return
             }
             credentials = OpenVPN.Credentials(username, password)
@@ -200,7 +200,7 @@ open class OpenVPNTunnelProvider: NEPacketTunnelProvider {
         cfg._appexSetLastError(nil)
 
         guard OpenVPN.prepareRandomNumberGenerator(seedLength: prngSeedLength) else {
-            completionHandler(OpenVPNProviderConfigurationError.prngInitialization)
+            completionHandler(ConfigurationError.prngInitialization)
             return
         }
 
@@ -216,8 +216,8 @@ open class OpenVPNTunnelProvider: NEPacketTunnelProvider {
         do {
             session = try OpenVPNSession(queue: tunnelQueue, configuration: cfg.configuration, cachesURL: cachesURL)
             refreshDataCount()
-        } catch let e {
+        } catch {
-            completionHandler(e)
+            completionHandler(error)
             return
         }
         session.credentials = credentials
@@ -359,7 +359,7 @@ open class OpenVPNTunnelProvider: NEPacketTunnelProvider {
             // from stopTunnel(), in which case we don't need to feed an error parameter to
             // the stop completion handler
             //
-            pendingStartHandler?(error ?? OpenVPNProviderError.socketActivity)
+            pendingStartHandler?(error ?? TunnelKitOpenVPNError.socketActivity)
             pendingStartHandler = nil
         }
         // stopped intentionally
@@ -434,9 +434,13 @@ extension OpenVPNTunnelProvider: GenericSocketDelegate {
         // look for error causing shutdown
         shutdownError = session.stopError
         if failure && (shutdownError == nil) {
-            shutdownError = OpenVPNProviderError.linkError
+            shutdownError = TunnelKitOpenVPNError.linkError
+        }
+        if case .negotiationTimeout = shutdownError as? OpenVPNError {
+            didTimeoutNegotiation = true
+        } else {
+            didTimeoutNegotiation = false
         }
-        didTimeoutNegotiation = (shutdownError as? OpenVPNError == .negotiationTimeout)
 
         // only try upgrade on network errors
         if shutdownError as? OpenVPNError == nil {
@@ -479,7 +483,7 @@ extension OpenVPNTunnelProvider: GenericSocketDelegate {
     public func socketHasBetterPath(_ socket: GenericSocket) {
         log.debug("Stopping tunnel due to a new better path")
         logCurrentSSID()
-        session?.reconnect(error: OpenVPNProviderError.networkChanged)
+        session?.reconnect(error: TunnelKitOpenVPNError.networkChanged)
     }
 }
 
@@ -546,7 +550,7 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
         let newSettings = NetworkSettingsBuilder(remoteAddress: remoteAddress, localOptions: localOptions, remoteOptions: remoteOptions)
 
         guard !newSettings.isGateway || newSettings.hasGateway else {
-            session?.shutdown(error: OpenVPNProviderError.gatewayUnattainable)
+            session?.shutdown(error: TunnelKitOpenVPNError.gatewayUnattainable)
             return
         }
 
@@ -594,7 +598,7 @@ extension OpenVPNTunnelProvider: OpenVPNSessionDelegate {
 extension OpenVPNTunnelProvider {
     private func tryNextEndpoint() -> Bool {
         guard strategy.tryNextEndpoint() else {
-            disposeTunnel(error: OpenVPNProviderError.exhaustedEndpoints)
+            disposeTunnel(error: TunnelKitOpenVPNError.exhaustedEndpoints)
             return false
         }
         return true
@@ -647,16 +651,61 @@ extension OpenVPNTunnelProvider {
 //        let anyObject = object as AnyObject
 //        return Unmanaged<AnyObject>.passUnretained(anyObject).toOpaque()
 //    }
+}
 
-    // MARK: Errors
+// MARK: Errors
 
-    private func setErrorStatus(with error: Error) {
+private extension OpenVPNTunnelProvider {
+    enum ConfigurationError: Error {
+
+        /// A field in the `OpenVPNProvider.Configuration` provided is incorrect or incomplete.
+        case parameter(name: String)
+
+        /// Credentials are missing or inaccessible.
+        case credentials(details: String)
+
+        /// The pseudo-random number generator could not be initialized.
+        case prngInitialization
+
+        /// The TLS certificate could not be serialized.
+        case certificateSerialization
+    }
+
+    func setErrorStatus(with error: Error) {
         cfg._appexSetLastError(unifiedError(from: error))
     }
 
-    private func unifiedError(from error: Error) -> OpenVPNProviderError {
+    func unifiedError(from error: Error) -> TunnelKitOpenVPNError {
-        if let te = error.openVPNErrorCode() {
+
-            switch te {
+        // XXX: error handling is limited by lastError serialization
+        // requirement, cannot return a generic Error here
+//        openVPNError(from: error) ?? error
+        openVPNError(from: error) ?? .linkError
+    }
+
+    func openVPNError(from error: Error) -> TunnelKitOpenVPNError? {
+        if let specificError = error as? OpenVPNError {
+            switch specificError.asNativeOpenVPNError ?? specificError {
+            case .negotiationTimeout, .pingTimeout, .staleSession:
+                return .timeout
+
+            case .badCredentials:
+                return .authentication
+
+            case .serverCompression:
+                return .serverCompression
+
+            case .failedLinkWrite:
+                return .linkError
+
+            case .noRouting:
+                return .routing
+
+            case .serverShutdown:
+                return .serverShutdown
+
+            case .native(let code):
+                switch code {
                 case .cryptoRandomGenerator, .cryptoAlgorithm:
                     return .encryptionInitialization
 
@@ -683,34 +732,17 @@ extension OpenVPNTunnelProvider {
                 default:
                     break
                 }
-        } else if let se = error as? OpenVPNError {
-            switch se {
-            case .negotiationTimeout, .pingTimeout, .staleSession:
-                return .timeout
-
-            case .badCredentials:
-                return .authentication
-
-            case .serverCompression:
-                return .serverCompression
-
-            case .failedLinkWrite:
-                return .linkError
-
-            case .noRouting:
-                return .routing
-
-            case .serverShutdown:
-                return .serverShutdown
 
             default:
                 return .unexpectedReply
             }
         }
-        return error as? OpenVPNProviderError ?? .linkError
+        return nil
     }
 }
 
+// MARK: Hacks
+
 private extension NEPacketTunnelProvider {
     func forceExitOnMac() {
         #if os(macOS)

Sources/TunnelKitOpenVPNAppExtension/ResolvedRemote.swift

@@ -64,7 +64,7 @@ class ResolvedRemote: CustomStringConvertible {
         }
     }
 
-    private func handleResult(_ result: Result<[DNSRecord], DNSError>) {
+    private func handleResult(_ result: Result<[DNSRecord], Error>) {
         switch result {
         case .success(let records):
             log.debug("DNS resolved addresses: \(records.map { $0.address }.maskedDescription)")

Sources/TunnelKitOpenVPNCore/ConfigurationError.swift

@@ -44,5 +44,8 @@ extension OpenVPN {
 
         /// Encryption passphrase is incorrect or key is corrupt.
         case unableToDecrypt(error: Error)
+
+        /// The PUSH_REPLY is multipart.
+        case continuationPushReply
     }
 }

Sources/TunnelKitOpenVPNCore/ConfigurationParser.swift

@@ -339,7 +339,7 @@ extension OpenVPN {
                     isContinuation = ($0.first == "2")
                 }
                 guard !isContinuation else {
-                    throw OpenVPNError.continuationPushReply
+                    throw ConfigurationError.continuationPushReply
                 }
 
                 // MARK: Inline content
@@ -805,8 +805,8 @@ extension OpenVPN {
                 }
                 do {
                     sessionBuilder.clientKey = try clientKey.decrypted(with: passphrase)
-                } catch let e {
+                } catch {
-                    throw ConfigurationError.unableToDecrypt(error: e)
+                    throw ConfigurationError.unableToDecrypt(error: error)
                 }
             } else {
                 sessionBuilder.clientKey = optClientKey

Sources/TunnelKitOpenVPNCore/OpenVPNError.swift

@@ -35,9 +35,10 @@
 //
 
 import Foundation
+import CTunnelKitOpenVPNCore
 
 /// The possible errors raised/thrown during `OpenVPNSession` operation.
-public enum OpenVPNError: String, Error {
+public enum OpenVPNError: Error {
 
     /// The negotiation timed out.
     case negotiationTimeout
@@ -51,15 +52,15 @@ public enum OpenVPNError: String, Error {
     /// The connection key is wrong or wasn't expected.
     case badKey
 
+    /// Control channel failure.
+    case controlChannel(message: String)
+
     /// The control packet has an incorrect prefix payload.
     case wrongControlDataPrefix
 
     /// The provided credentials failed authentication.
     case badCredentials
 
-    /// The PUSH_REPLY is multipart.
-    case continuationPushReply
-
     /// The reply to PUSH_REQUEST is malformed.
     case malformedPushReply
 
@@ -80,4 +81,17 @@ public enum OpenVPNError: String, Error {
 
     /// Remote server shut down (--explicit-exit-notify).
     case serverShutdown
+
+    /// NSError from ObjC layer.
+    case native(code: OpenVPNErrorCode)
+}
+
+extension Error {
+    public var asNativeOpenVPNError: OpenVPNError? {
+        let nativeError = self as NSError
+        guard nativeError.domain == OpenVPNErrorDomain, let code = OpenVPNErrorCode(rawValue: nativeError.code) else {
+            return nil
+        }
+        return .native(code: code)
+    }
 }

Sources/TunnelKitOpenVPNManager/OpenVPN+ProviderConfiguration.swift

@@ -139,7 +139,7 @@ extension OpenVPN.ProviderConfiguration {
     /**
      The last error reported by the tunnel, if any.
      */
-    public var lastError: OpenVPNProviderError? {
+    public var lastError: TunnelKitOpenVPNError? {
         return defaults?.openVPNLastError
     }
 
@@ -164,7 +164,7 @@ extension OpenVPN.ProviderConfiguration {
         defaults?.openVPNServerConfiguration = newValue
     }
 
-    public func _appexSetLastError(_ newValue: OpenVPNProviderError?) {
+    public func _appexSetLastError(_ newValue: TunnelKitOpenVPNError?) {
         defaults?.openVPNLastError = newValue
     }
 
@@ -250,12 +250,12 @@ extension UserDefaults {
         }
     }
 
-    public fileprivate(set) var openVPNLastError: OpenVPNProviderError? {
+    public fileprivate(set) var openVPNLastError: TunnelKitOpenVPNError? {
         get {
             guard let rawValue = string(forKey: OpenVPN.ProviderConfiguration.Keys.lastError.rawValue) else {
                 return nil
             }
-            return OpenVPNProviderError(rawValue: rawValue)
+            return TunnelKitOpenVPNError(rawValue: rawValue)
         }
         set {
             guard let newValue = newValue else {

Sources/TunnelKitOpenVPNManager/TunnelKitOpenVPNError.swift

@@ -1,5 +1,5 @@
 //
-//  OpenVPNProviderError.swift
+//  TunnelKitOpenVPNError.swift
 //  TunnelKit
 //
 //  Created by Davide De Rosa on 11/8/21.
@@ -35,25 +35,10 @@
 //
 
 import Foundation
-
+import TunnelKitOpenVPNCore
-/// Mostly programming errors by host app.
-public enum OpenVPNProviderConfigurationError: Error {
-
-    /// A field in the `OpenVPNProvider.Configuration` provided is incorrect or incomplete.
-    case parameter(name: String)
-
-    /// Credentials are missing or inaccessible.
-    case credentials(details: String)
-
-    /// The pseudo-random number generator could not be initialized.
-    case prngInitialization
-
-    /// The TLS certificate could not be serialized.
-    case certificateSerialization
-}
 
 /// The errors causing a tunnel disconnection.
-public enum OpenVPNProviderError: String, Error {
+public enum TunnelKitOpenVPNError: String, Error {
 
     /// Socket endpoint could not be resolved.
     case dnsFailure

Sources/TunnelKitOpenVPNProtocol/ControlChannel.swift

@@ -33,14 +33,6 @@ import CTunnelKitOpenVPNProtocol
 private let log = SwiftyBeaver.self
 
 extension OpenVPN {
-    class ControlChannelError: Error, CustomStringConvertible {
-        let description: String
-
-        init(_ message: String) {
-            description = "\(String(describing: ControlChannelError.self))(\(message))"
-        }
-    }
-
     class ControlChannel {
         private let serializer: ControlChannelSerializer
 
@@ -101,12 +93,17 @@ extension OpenVPN {
         }
 
         func readInboundPacket(withData data: Data, offset: Int) throws -> ControlPacket {
+            do {
                 let packet = try serializer.deserialize(data: data, start: offset, end: nil)
                 log.debug("Control: Read packet \(packet)")
                 if let ackIds = packet.ackIds as? [UInt32], let ackRemoteSessionId = packet.ackRemoteSessionId {
                     try readAcks(ackIds, acksRemoteSessionId: ackRemoteSessionId)
                 }
                 return packet
+            } catch {
+                log.error("Control: Channel failure \(error)")
+                throw error
+            }
         }
 
         func enqueueInboundPacket(packet: ControlPacket) -> [ControlPacket] {

Sources/TunnelKitOpenVPNProtocol/ControlChannelSerializer.swift

@@ -54,11 +54,11 @@ extension OpenVPN.ControlChannel {
             let end = end ?? packet.count
 
             guard end >= offset + PacketOpcodeLength else {
-                throw OpenVPN.ControlChannelError("Missing opcode")
+                throw OpenVPNError.controlChannel(message: "Missing opcode")
             }
             let codeValue = packet[offset] >> 3
             guard let code = PacketCode(rawValue: codeValue) else {
-                throw OpenVPN.ControlChannelError("Unknown code: \(codeValue))")
+                throw OpenVPNError.controlChannel(message: "Unknown code: \(codeValue))")
             }
             let key = packet[offset] & 0b111
             offset += PacketOpcodeLength
@@ -66,13 +66,13 @@ extension OpenVPN.ControlChannel {
             log.debug("Control: Try read packet with code \(code) and key \(key)")
 
             guard end >= offset + PacketSessionIdLength else {
-                throw OpenVPN.ControlChannelError("Missing sessionId")
+                throw OpenVPNError.controlChannel(message: "Missing sessionId")
             }
             let sessionId = packet.subdata(offset: offset, count: PacketSessionIdLength)
             offset += PacketSessionIdLength
 
             guard end >= offset + 1 else {
-                throw OpenVPN.ControlChannelError("Missing ackSize")
+                throw OpenVPNError.controlChannel(message: "Missing ackSize")
             }
             let ackSize = packet[offset]
             offset += 1
@@ -81,7 +81,7 @@ extension OpenVPN.ControlChannel {
             var ackRemoteSessionId: Data?
             if ackSize > 0 {
                 guard end >= (offset + Int(ackSize) * PacketIdLength) else {
-                    throw OpenVPN.ControlChannelError("Missing acks")
+                    throw OpenVPNError.controlChannel(message: "Missing acks")
                 }
                 var ids: [UInt32] = []
                 for _ in 0..<ackSize {
@@ -91,7 +91,7 @@ extension OpenVPN.ControlChannel {
                 }
 
                 guard end >= offset + PacketSessionIdLength else {
-                    throw OpenVPN.ControlChannelError("Missing remoteSessionId")
+                    throw OpenVPNError.controlChannel(message: "Missing remoteSessionId")
                 }
                 let remoteSessionId = packet.subdata(offset: offset, count: PacketSessionIdLength)
                 offset += PacketSessionIdLength
@@ -102,16 +102,16 @@ extension OpenVPN.ControlChannel {
 
             if code == .ackV1 {
                 guard let ackIds = ackIds else {
-                    throw OpenVPN.ControlChannelError("Ack packet without ids")
+                    throw OpenVPNError.controlChannel(message: "Ack packet without ids")
                 }
                 guard let ackRemoteSessionId = ackRemoteSessionId else {
-                    throw OpenVPN.ControlChannelError("Ack packet without remoteSessionId")
+                    throw OpenVPNError.controlChannel(message: "Ack packet without remoteSessionId")
                 }
                 return ControlPacket(key: key, sessionId: sessionId, ackIds: ackIds as [NSNumber], ackRemoteSessionId: ackRemoteSessionId)
             }
 
             guard end >= offset + PacketIdLength else {
-                throw OpenVPN.ControlChannelError("Missing packetId")
+                throw OpenVPNError.controlChannel(message: "Missing packetId")
             }
             let packetId = packet.networkUInt32Value(from: offset)
             offset += PacketIdLength
@@ -192,7 +192,7 @@ extension OpenVPN.ControlChannel {
 
             // data starts with (prefix=(header + sessionId) + auth=(hmac + replayId))
             guard end >= preambleLength else {
-                throw OpenVPN.ControlChannelError("Missing HMAC")
+                throw OpenVPNError.controlChannel(message: "Missing HMAC")
             }
 
             // needs a copy for swapping
@@ -206,7 +206,12 @@ extension OpenVPN.ControlChannel {
 
             // TODO: validate replay packet id
 
+            do {
                 return try plain.deserialize(data: authPacket, start: authLength, end: nil)
+            } catch {
+                log.error("Control: Channel failure \(error)")
+                throw error
+            }
         }
     }
 }
@@ -269,7 +274,7 @@ extension OpenVPN.ControlChannel {
 
             // data starts with (ad=(header + sessionId + replayId) + tag)
             guard end >= start + adLength + tagLength else {
-                throw OpenVPN.ControlChannelError("Missing AD+TAG")
+                throw OpenVPNError.controlChannel(message: "Missing AD+TAG")
             }
 
             let encryptedCount = packet.count - adLength
@@ -288,7 +293,12 @@ extension OpenVPN.ControlChannel {
 
             // TODO: validate replay packet id
 
+            do {
                 return try plain.deserialize(data: decryptedPacket, start: 0, end: nil)
+            } catch {
+                log.error("Control: Channel failure \(error)")
+                throw error
+            }
         }
     }
 }

Sources/TunnelKitOpenVPNProtocol/OpenVPNSession.swift

@@ -477,8 +477,8 @@ public class OpenVPNSession: Session {
                     continue
                 }
                 controlPacket = parsedPacket
-            } catch let e {
+            } catch {
-                log.warning("Dropped malformed packet: \(e)")
+                log.warning("Dropped malformed packet: \(error)")
                 continue
 //                deferStop(.shutdown, e)
 //                return
@@ -573,8 +573,8 @@ public class OpenVPNSession: Session {
         authenticator = nil
         do {
             try controlChannel.reset(forNewSession: forNewSession)
-        } catch let e {
+        } catch {
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
         }
     }
 
@@ -658,18 +658,18 @@ public class OpenVPNSession: Session {
             authenticator = try OpenVPN.Authenticator(credentials?.username, pushReply?.options.authToken ?? credentials?.password)
             authenticator?.withLocalOptions = withLocalOptions
             try authenticator?.putAuth(into: negotiationKey.tls, options: configuration)
-        } catch let e {
+        } catch {
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
             return
         }
 
         let cipherTextOut: Data
         do {
             cipherTextOut = try negotiationKey.tls.pullCipherText()
-        } catch let e {
+        } catch {
-            if let _ = e.openVPNErrorCode() {
+            if let nativeError = error.asNativeOpenVPNError {
-                log.error("TLS.auth: Failed pulling ciphertext (error: \(e))")
+                log.error("TLS.auth: Failed pulling ciphertext (error: \(nativeError))")
-                shutdown(error: e)
+                shutdown(error: nativeError)
                 return
             }
             log.verbose("TLS.auth: Still can't pull ciphertext")
@@ -695,10 +695,10 @@ public class OpenVPNSession: Session {
         let cipherTextOut: Data
         do {
             cipherTextOut = try negotiationKey.tls.pullCipherText()
-        } catch let e {
+        } catch {
-            if let _ = e.openVPNErrorCode() {
+            if let nativeError = error.asNativeOpenVPNError {
-                log.error("TLS.auth: Failed pulling ciphertext (error: \(e))")
+                log.error("TLS.auth: Failed pulling ciphertext (error: \(nativeError))")
-                shutdown(error: e)
+                shutdown(error: nativeError)
                 return
             }
             log.verbose("TLS.ifconfig: Still can't pull ciphertext")
@@ -789,21 +789,21 @@ public class OpenVPNSession: Session {
             negotiationKey.tlsOptional = tls
             do {
                 try negotiationKey.tls.start()
-            } catch let e {
+            } catch {
-                deferStop(.shutdown, e)
+                deferStop(.shutdown, error)
                 return
             }
 
             let cipherTextOut: Data
             do {
                 cipherTextOut = try negotiationKey.tls.pullCipherText()
-            } catch let e {
+            } catch {
-                if let _ = e.openVPNErrorCode() {
+                if let nativeError = error.asNativeOpenVPNError {
-                    log.error("TLS.connect: Failed pulling ciphertext (error: \(e))")
+                    log.error("TLS.connect: Failed pulling ciphertext (error: \(nativeError))")
-                    shutdown(error: e)
+                    shutdown(error: nativeError)
                     return
                 }
-                deferStop(.shutdown, e)
+                deferStop(.shutdown, error)
                 return
             }
 
@@ -836,10 +836,10 @@ public class OpenVPNSession: Session {
                 cipherTextOut = try negotiationKey.tls.pullCipherText()
                 log.debug("TLS.connect: Send pulled ciphertext (\(cipherTextOut.count) bytes)")
                 enqueueControlPackets(code: .controlV1, key: negotiationKey.id, payload: cipherTextOut)
-            } catch let e {
+            } catch {
-                if let _ = e.openVPNErrorCode() {
+                if let nativeError = error.asNativeOpenVPNError {
-                    log.error("TLS.connect: Failed pulling ciphertext (error: \(e))")
+                    log.error("TLS.connect: Failed pulling ciphertext (error: \(nativeError))")
-                    shutdown(error: e)
+                    shutdown(error: nativeError)
                     return
                 }
                 log.verbose("TLS.connect: No available ciphertext to pull")
@@ -878,8 +878,8 @@ public class OpenVPNSession: Session {
                 guard try auth.parseAuthReply() else {
                     return
                 }
-            } catch let e {
+            } catch {
-                deferStop(.shutdown, e)
+                deferStop(.shutdown, error)
                 return
             }
 
@@ -962,12 +962,12 @@ public class OpenVPNSession: Session {
                     throw OpenVPNError.serverCompression
                 }
             }
-        } catch OpenVPNError.continuationPushReply {
+        } catch OpenVPN.ConfigurationError.continuationPushReply {
             continuatedPushReplyMessage = completeMessage.replacingOccurrences(of: "push-continuation", with: "")
             // FIXME: strip "PUSH_REPLY" and "push-continuation 2"
             return
-        } catch let e {
+        } catch {
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
             return
         }
 
@@ -1025,9 +1025,9 @@ public class OpenVPNSession: Session {
         let rawList: [Data]
         do {
             rawList = try controlChannel.writeOutboundPackets()
-        } catch let e {
+        } catch {
-            log.warning("Failed control packet serialization: \(e)")
+            log.warning("Failed control packet serialization: \(error)")
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
             return
         }
         for raw in rawList {
@@ -1110,8 +1110,8 @@ public class OpenVPNSession: Session {
                 sessionId,
                 remoteSessionId
             )
-        } catch let e {
+        } catch {
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
             return
         }
 
@@ -1141,12 +1141,12 @@ public class OpenVPNSession: Session {
             }
 
             tunnel?.writePackets(decryptedPackets, completionHandler: nil)
-        } catch let e {
+        } catch {
-            guard !e.isOpenVPNError() else {
+            if let nativeError = error.asNativeOpenVPNError {
-                deferStop(.shutdown, e)
+                deferStop(.shutdown, nativeError)
                 return
             }
-            deferStop(.reconnect, e)
+            deferStop(.reconnect, error)
         }
     }
 
@@ -1181,12 +1181,12 @@ public class OpenVPNSession: Session {
 //                    log.verbose("Data: \(encryptedPackets.count) packets successfully written to LINK")
                 }
             }
-        } catch let e {
+        } catch {
-            guard !e.isOpenVPNError() else {
+            if let nativeError = error.asNativeOpenVPNError {
-                deferStop(.shutdown, e)
+                deferStop(.shutdown, nativeError)
                 return
             }
-            deferStop(.reconnect, e)
+            deferStop(.reconnect, error)
         }
     }
 
@@ -1206,8 +1206,8 @@ public class OpenVPNSession: Session {
                 ackPacketIds: [controlPacket.packetId],
                 ackRemoteSessionId: controlPacket.sessionId
             )
-        } catch let e {
+        } catch {
-            deferStop(.shutdown, e)
+            deferStop(.shutdown, error)
             return
         }
 

Sources/TunnelKitWireGuardAppExtension/WireGuardTunnelProvider.swift

@@ -36,7 +36,7 @@ open class WireGuardTunnelProvider: NEPacketTunnelProvider {
             cfg = try fromDictionary(WireGuard.ProviderConfiguration.self, providerConfiguration)
             tunnelConfiguration = cfg.configuration.tunnelConfiguration
         } catch {
-            completionHandler(WireGuardProviderError.savedProtocolConfigurationIsInvalid)
+            completionHandler(TunnelKitWireGuardError.savedProtocolConfigurationIsInvalid)
             return
         }
 
@@ -59,24 +59,24 @@ open class WireGuardTunnelProvider: NEPacketTunnelProvider {
             case .cannotLocateTunnelFileDescriptor:
                 wg_log(.error, staticMessage: "Starting tunnel failed: could not determine file descriptor")
                 self.cfg._appexSetLastError(.couldNotDetermineFileDescriptor)
-                completionHandler(WireGuardProviderError.couldNotDetermineFileDescriptor)
+                completionHandler(TunnelKitWireGuardError.couldNotDetermineFileDescriptor)
 
             case .dnsResolution(let dnsErrors):
                 let hostnamesWithDnsResolutionFailure = dnsErrors.map(\.address)
                     .joined(separator: ", ")
                 wg_log(.error, message: "DNS resolution failed for the following hostnames: \(hostnamesWithDnsResolutionFailure)")
                 self.cfg._appexSetLastError(.dnsResolutionFailure)
-                completionHandler(WireGuardProviderError.dnsResolutionFailure)
+                completionHandler(TunnelKitWireGuardError.dnsResolutionFailure)
 
             case .setNetworkSettings(let error):
                 wg_log(.error, message: "Starting tunnel failed with setTunnelNetworkSettings returning \(error.localizedDescription)")
                 self.cfg._appexSetLastError(.couldNotSetNetworkSettings)
-                completionHandler(WireGuardProviderError.couldNotSetNetworkSettings)
+                completionHandler(TunnelKitWireGuardError.couldNotSetNetworkSettings)
 
             case .startWireGuardBackend(let errorCode):
                 wg_log(.error, message: "Starting tunnel failed with wgTurnOn returning \(errorCode)")
                 self.cfg._appexSetLastError(.couldNotStartBackend)
-                completionHandler(WireGuardProviderError.couldNotStartBackend)
+                completionHandler(TunnelKitWireGuardError.couldNotStartBackend)
 
             case .invalidState:
                 // Must never happen

Sources/TunnelKitWireGuardManager/TunnelKitWireGuardError.swift

@@ -3,7 +3,7 @@
 
 import Foundation
 
-public enum WireGuardProviderError: String, Error {
+public enum TunnelKitWireGuardError: String, Error {
     case savedProtocolConfigurationIsInvalid
     case dnsResolutionFailure
     case couldNotStartBackend

Sources/TunnelKitWireGuardManager/WireGuard+ProviderConfiguration.swift

@@ -91,7 +91,7 @@ extension WireGuard.ProviderConfiguration: NetworkExtensionConfiguration {
 // MARK: Shared data
 
 extension WireGuard.ProviderConfiguration {
-    public var lastError: WireGuardProviderError? {
+    public var lastError: TunnelKitWireGuardError? {
         return defaults?.wireGuardLastError
     }
 
@@ -105,7 +105,7 @@ extension WireGuard.ProviderConfiguration {
 }
 
 extension WireGuard.ProviderConfiguration {
-    public func _appexSetLastError(_ newValue: WireGuardProviderError?) {
+    public func _appexSetLastError(_ newValue: TunnelKitWireGuardError?) {
         defaults?.wireGuardLastError = newValue
     }
 
@@ -131,12 +131,12 @@ extension UserDefaults {
             .appendingPathComponent(path)
     }
 
-    public fileprivate(set) var wireGuardLastError: WireGuardProviderError? {
+    public fileprivate(set) var wireGuardLastError: TunnelKitWireGuardError? {
         get {
             guard let rawValue = string(forKey: WireGuard.ProviderConfiguration.Keys.lastError.rawValue) else {
                 return nil
             }
-            return WireGuardProviderError(rawValue: rawValue)
+            return TunnelKitWireGuardError(rawValue: rawValue)
         }
         set {
             guard let newValue = newValue else {

Tests/TunnelKitOpenVPNTests/ControlChannelTests.swift

@@ -82,8 +82,8 @@ class ControlChannelTests: XCTestCase {
         let packet: ControlPacket
         do {
             packet = try client.deserialize(data: original, start: 0, end: nil)
-        } catch let e {
+        } catch {
-            XCTAssertNil(e)
+            XCTAssertNil(error)
             return
         }
         XCTAssertEqual(packet.code, .hardResetClientV2)
@@ -94,8 +94,8 @@ class ControlChannelTests: XCTestCase {
         let raw: Data
         do {
             raw = try server.serialize(packet: packet, timestamp: timestamp)
-        } catch let e {
+        } catch {
-            XCTAssertNil(e)
+            XCTAssertNil(error)
             return
         }
         print("raw: \(raw.toHex())")
@@ -113,8 +113,8 @@ class ControlChannelTests: XCTestCase {
         let packet: ControlPacket
         do {
             packet = try client.deserialize(data: original, start: 0, end: nil)
-        } catch let e {
+        } catch {
-            XCTAssertNil(e)
+            XCTAssertNil(error)
             return
         }
         XCTAssertEqual(packet.code, .hardResetServerV2)
@@ -126,8 +126,8 @@ class ControlChannelTests: XCTestCase {
         let raw: Data
         do {
             raw = try server.serialize(packet: packet, timestamp: timestamp)
-        } catch let e {
+        } catch {
-            XCTAssertNil(e)
+            XCTAssertNil(error)
             return
         }
         print("raw: \(raw.toHex())")