tunnelkit/TunnelKit/Sources/AppExtension/TunnelKitProvider+Interaction.swift

//
//  TunnelKitProvider+Interaction.swift
//  TunnelKit
//
//  Created by Davide De Rosa on 9/24/17.
//  Copyright (c) 2018 Davide De Rosa. All rights reserved.
//
//  https://github.com/keeshux
//
//  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/>.
//
//  This file incorporates work covered by the following copyright and
//  permission notice:
//
//      Copyright (c) 2018-Present Private Internet Access
//
//      Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
//
//      The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
//      THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//

import Foundation

extension TunnelKitProvider {

    // MARK: Interaction

    /// The messages accepted by `TunnelKitProvider`.
    public class Message: Equatable {
        
        /// Requests a snapshot of the latest debug log. Returns the log data decoded from UTF-8.
        public static let requestLog = Message(0xff)
        
        /// Requests the current bytes count from data channel (if connected).
        ///
        /// Data is 16 bytes: low 8 = received, high 8 = sent.
        public static let dataCount = Message(0xfe)
        
        /// The underlying raw message `Data` to forward to the tunnel via IPC.
        public let data: Data
        
        private init(_ byte: UInt8) {
            data = Data(bytes: [byte])
        }
        
        init(_ data: Data) {
            self.data = data
        }
        
        // MARK: Equatable

        /// :nodoc:
        public static func ==(lhs: Message, rhs: Message) -> Bool {
            return (lhs.data == rhs.data)
        }
    }

    // mostly programming errors by host app
    enum ProviderConfigurationError: Error {
        
        /// A field in the `TunnelKitProvider.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 ProviderError: String, Error {
        
        /// Socket endpoint could not be resolved.
        case dnsFailure
        
        /// No more protocols available to try.
        case exhaustedProtocols
        
        /// Socket failed to reach active state.
        case socketActivity
        
        /// Credentials authentication failed.
        case authentication
        
        /// TLS could not be initialized (e.g. malformed CA or client PEMs).
        case tlsInitialization

        /// TLS server verification failed.
        case tlsServerVerification

        /// TLS handshake failed.
        case tlsHandshake
        
        /// The encryption logic could not be initialized (e.g. PRNG, algorithms).
        case encryptionInitialization
        
        /// Data encryption/decryption failed.
        case encryptionData
        
        /// Server uses compression and this is not supported.
        case serverCompression
        
        /// Tunnel timed out.
        case timeout
        
        /// An error occurred at the link level.
        case linkError
        
        /// The current network changed (e.g. switched from WiFi to data connection).
        case networkChanged
        
        /// The server replied in an unexpected way.
        case unexpectedReply
    }
}