Move in/out states to a generic struct

.jazzy.yaml

@@ -18,6 +18,7 @@ custom_categories:
         - LinkInterface
         - TunnelInterface
         - PacketStream
+        - BidirectionalState
         - SessionProxy
         - SessionProxyDelegate
         - SessionReply

TunnelKit.xcodeproj/project.pbxproj

@@ -30,6 +30,8 @@
 		0E1108B31F77B9F900A92462 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 0E1108B21F77B9F900A92462 /* Assets.xcassets */; };
 		0E1108B61F77B9F900A92462 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 0E1108B41F77B9F900A92462 /* LaunchScreen.storyboard */; };
 		0E12B2A32145341B00B4BAE9 /* PacketTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0E12B2A22145341B00B4BAE9 /* PacketTests.swift */; };
+		0E12B2A521454F7F00B4BAE9 /* BidirectionalState.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0E12B2A421454F7F00B4BAE9 /* BidirectionalState.swift */; };
+		0E12B2A621454F7F00B4BAE9 /* BidirectionalState.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0E12B2A421454F7F00B4BAE9 /* BidirectionalState.swift */; };
 		0E245D692135972800B012A2 /* PushTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0E245D682135972800B012A2 /* PushTests.swift */; };
 		0E245D6C2137F73600B012A2 /* CompressionFramingNative.h in Headers */ = {isa = PBXBuildFile; fileRef = 0E245D6B2137F73600B012A2 /* CompressionFramingNative.h */; };
 		0E39BCE8214B2AB60035E9DE /* ControlPacket.h in Headers */ = {isa = PBXBuildFile; fileRef = 0E39BCE6214B2AB60035E9DE /* ControlPacket.h */; };
@@ -195,6 +197,7 @@
 		0E1108B51F77B9F900A92462 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/LaunchScreen.storyboard; sourceTree = "<group>"; };
 		0E1108B71F77B9F900A92462 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		0E12B2A22145341B00B4BAE9 /* PacketTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PacketTests.swift; sourceTree = "<group>"; };
+		0E12B2A421454F7F00B4BAE9 /* BidirectionalState.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BidirectionalState.swift; sourceTree = "<group>"; };
 		0E17D7F91F730D9F009EE129 /* TunnelKit.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = TunnelKit.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		0E245D682135972800B012A2 /* PushTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PushTests.swift; sourceTree = "<group>"; };
 		0E245D6B2137F73600B012A2 /* CompressionFramingNative.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = CompressionFramingNative.h; sourceTree = "<group>"; };
@@ -424,6 +427,7 @@
 			children = (
 				0EFEB42E2006D3C800F81029 /* Allocation.h */,
 				0EFEB4462006D3C800F81029 /* Allocation.m */,
+				0E12B2A421454F7F00B4BAE9 /* BidirectionalState.swift */,
 				0E245D6B2137F73600B012A2 /* CompressionFramingNative.h */,
 				0E39BCE6214B2AB60035E9DE /* ControlPacket.h */,
 				0E39BCE7214B2AB60035E9DE /* ControlPacket.m */,
@@ -884,6 +888,7 @@
 				0EFEB4782006D3C800F81029 /* TunnelKitProvider+Configuration.swift in Sources */,
 				0E3E0F212108A8CC00B371C1 /* SessionProxy+PushReply.swift in Sources */,
 				0EFEB4752006D3C800F81029 /* Errors.m in Sources */,
+				0E12B2A521454F7F00B4BAE9 /* BidirectionalState.swift in Sources */,
 				0EBBF2E52084FE6F00E36B40 /* GenericSocket.swift in Sources */,
 				0EFEB4762006D3C800F81029 /* DataPath.m in Sources */,
 				0E0C2127212ED29D008AB282 /* SessionProxy+Configuration.swift in Sources */,
@@ -936,6 +941,7 @@
 				0EFEB4A42006D7F300F81029 /* DataPath.m in Sources */,
 				0EBBF2E62084FE6F00E36B40 /* GenericSocket.swift in Sources */,
 				0E3E0F222108A8CC00B371C1 /* SessionProxy+PushReply.swift in Sources */,
+				0E12B2A621454F7F00B4BAE9 /* BidirectionalState.swift in Sources */,
 				0EFEB4912006D7F300F81029 /* TLSBox.m in Sources */,
 				0EFEB49D2006D7F300F81029 /* IOInterface.swift in Sources */,
 				0E0C2128212ED29D008AB282 /* SessionProxy+Configuration.swift in Sources */,

TunnelKit/Sources/AppExtension/TunnelKitProvider.swift

@@ -281,8 +281,8 @@ open class TunnelKitProvider: NEPacketTunnelProvider {
         case .dataCount:
             if let proxy = proxy {
                 response = Data()
-                response?.append(UInt64(proxy.bytesIn))
+                response?.append(UInt64(proxy.bytesCount.inbound))
-                response?.append(UInt64(proxy.bytesOut))
+                response?.append(UInt64(proxy.bytesCount.outbound))
             }
             
         default:

TunnelKit/Sources/Core/BidirectionalState.swift

@@ -0,0 +1,65 @@
+//
+//  BidirectionalState.swift
+//  TunnelKit
+//
+//  Created by Davide De Rosa on 9/9/18.
+//  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/>.
+//
+
+import Foundation
+
+/// A generic structure holding a pair of inbound/outbound states.
+public class BidirectionalState<T> {
+    private let resetValue: T
+
+    /// The inbound state.
+    public var inbound: T
+    
+    /// The outbound state.
+    public var outbound: T
+    
+    /**
+     Returns current state as a pair.
+     
+     - Returns: Current state as a pair, inbound first.
+     */
+    public var pair: (T, T) {
+        return (inbound, outbound)
+    }
+    
+    /**
+     Inits state with a value that will later be reused by `reset()`.
+     
+     - Parameter value: The value to initialize with and reset to.
+     */
+    public init(withResetValue value: T) {
+        inbound = value
+        outbound = value
+        resetValue = value
+    }
+    
+    /**
+     Resets state to the value provided with `init(withResetValue:)`.
+     */
+    public func reset() {
+        inbound = resetValue
+        outbound = resetValue
+    }
+}

TunnelKit/Sources/Core/SessionProxy.swift

@@ -146,9 +146,7 @@ public class SessionProxy {
     
     private var connectedDate: Date?
 
-    private var lastPingOut: Date
+    private var lastPing: BidirectionalState<Date>
-    
-    private var lastPingIn: Date
     
     private var isStopping: Bool
     
@@ -159,23 +157,17 @@ public class SessionProxy {
     
     private let controlPlainBuffer: ZeroingData
 
-    private var controlQueueOut: [ControlPacket]
+    private var controlQueue: BidirectionalState<[ControlPacket]>
-
-    private var controlQueueIn: [ControlPacket]
 
     private var controlPendingAcks: Set<UInt32>
     
-    private var controlPacketIdOut: UInt32
+    private var controlPacketId: BidirectionalState<UInt32>
-
-    private var controlPacketIdIn: UInt32
     
     private var authenticator: Authenticator?
     
     // MARK: Data
     
-    private(set) var bytesIn: Int
+    private(set) var bytesCount: BidirectionalState<Int>
-    
-    private(set) var bytesOut: Int
     
     // MARK: Init
 
@@ -192,18 +184,14 @@ public class SessionProxy {
         keys = [:]
         oldKeys = []
         negotiationKeyIdx = 0
-        lastPingOut = Date.distantPast
+        lastPing = BidirectionalState(withResetValue: Date.distantPast)
-        lastPingIn = Date.distantPast
         isStopping = false
         
         controlPlainBuffer = Z(count: TLSBoxMaxBufferLength)
-        controlQueueOut = []
+        controlQueue = BidirectionalState(withResetValue: [])
-        controlQueueIn = []
         controlPendingAcks = []
-        controlPacketIdOut = 0
+        controlPacketId = BidirectionalState(withResetValue: 0)
-        controlPacketIdIn = 0
+        bytesCount = BidirectionalState(withResetValue: 0)
-        bytesIn = 0
-        bytesOut = 0
     }
     
     deinit {
@@ -433,7 +421,7 @@ public class SessionProxy {
             return
         }
         
-        lastPingIn = Date()
+        lastPing.inbound = Date()
 
         var dataPacketsByKey = [UInt8: [Data]]()
         
@@ -545,22 +533,22 @@ public class SessionProxy {
             }
 
             let controlPacket = ControlPacket(code: code, key: key, sessionId: sessionId, packetId: packetId, payload: payload)
-            controlQueueIn.append(controlPacket)
+            controlQueue.inbound.append(controlPacket)
-            controlQueueIn.sort { $0.packetId < $1.packetId }
+            controlQueue.inbound.sort { $0.packetId < $1.packetId }
             
-            for queuedControlPacket in controlQueueIn {
+            for queuedControlPacket in controlQueue.inbound {
-                if (queuedControlPacket.packetId < controlPacketIdIn) {
+                if (queuedControlPacket.packetId < controlPacketId.inbound) {
-                    controlQueueIn.removeFirst()
+                    controlQueue.inbound.removeFirst()
                     continue
                 }
-                if (queuedControlPacket.packetId != controlPacketIdIn) {
+                if (queuedControlPacket.packetId != controlPacketId.inbound) {
                     continue
                 }
 
                 handleControlPacket(queuedControlPacket)
 
-                controlPacketIdIn += 1
+                controlPacketId.inbound += 1
-                controlQueueIn.removeFirst()
+                controlQueue.inbound.removeFirst()
             }
         }
 
@@ -580,7 +568,7 @@ public class SessionProxy {
             return
         }
         sendDataPackets(packets)
-        lastPingOut = Date()
+        lastPing.outbound = Date()
     }
     
     // Ruby: ping
@@ -590,14 +578,14 @@ public class SessionProxy {
         }
         
         let now = Date()
-        guard (now.timeIntervalSince(lastPingIn) <= CoreConfiguration.pingTimeout) else {
+        guard (now.timeIntervalSince(lastPing.inbound) <= CoreConfiguration.pingTimeout) else {
             deferStop(.shutdown, SessionError.pingTimeout)
             return
         }
 
         // postpone ping if elapsed less than keep-alive
         if let interval = keepAliveInterval {
-            let elapsed = now.timeIntervalSince(lastPingOut)
+            let elapsed = now.timeIntervalSince(lastPing.outbound)
             guard (elapsed >= interval) else {
                 scheduleNextPing(elapsed: elapsed)
                 return
@@ -606,7 +594,7 @@ public class SessionProxy {
 
         log.debug("Send ping")
         sendDataPackets([DataPacket.pingString])
-        lastPingOut = Date()
+        lastPing.outbound = Date()
 
         scheduleNextPing()
     }
@@ -626,14 +614,11 @@ public class SessionProxy {
     // Ruby: reset_ctrl
     private func resetControlChannel() {
         controlPlainBuffer.zero()
-        controlQueueOut.removeAll()
+        controlQueue.reset()
-        controlQueueIn.removeAll()
         controlPendingAcks.removeAll()
-        controlPacketIdOut = 0
+        controlPacketId.reset()
-        controlPacketIdIn = 0
         authenticator = nil
-        bytesIn = 0
+        bytesCount.reset()
-        bytesOut = 0
     }
     
     // Ruby: hard_reset
@@ -942,7 +927,7 @@ public class SessionProxy {
             fatalError("Missing sessionId, do hardReset() first")
         }
         
-        let oldIdOut = controlPacketIdOut
+        let oldIdOut = controlPacketId.outbound
         let maxCount = link.mtu
         var queuedCount = 0
         var offset = 0
@@ -950,19 +935,19 @@ public class SessionProxy {
         repeat {
             let subPayloadLength = min(maxCount, payload.count - offset)
             let subPayloadData = payload.subdata(offset: offset, count: subPayloadLength)
-            let packet = ControlPacket(code: code, key: key, sessionId: sessionId, packetId: controlPacketIdOut, payload: subPayloadData)
+            let packet = ControlPacket(code: code, key: key, sessionId: sessionId, packetId: controlPacketId.outbound, payload: subPayloadData)
             
-            controlQueueOut.append(packet)
+            controlQueue.outbound.append(packet)
-            controlPacketIdOut += 1
+            controlPacketId.outbound += 1
             offset += maxCount
             queuedCount += subPayloadLength
         } while (offset < payload.count)
         
         assert(queuedCount == payload.count)
         
-        let packetCount = controlPacketIdOut - oldIdOut
+        let packetCount = controlPacketId.outbound - oldIdOut
         if (packetCount > 1) {
-            log.debug("Enqueued \(packetCount) control packets [\(oldIdOut)-\(controlPacketIdOut - 1)]")
+            log.debug("Enqueued \(packetCount) control packets [\(oldIdOut)-\(controlPacketId.outbound - 1)]")
         } else {
             log.debug("Enqueued 1 control packet [\(oldIdOut)]")
         }
@@ -972,7 +957,7 @@ public class SessionProxy {
     
     // Ruby: flush_ctrl_q_out
     private func flushControlQueue() {
-        for controlPacket in controlQueueOut {
+        for controlPacket in controlQueue.outbound {
             if let sentDate = controlPacket.sentDate {
                 let timeAgo = -sentDate.timeIntervalSinceNow
                 guard (timeAgo >= CoreConfiguration.retransmissionLimit) else {
@@ -1083,7 +1068,7 @@ public class SessionProxy {
 
     // Ruby: handle_data_pkt
     private func handleDataPackets(_ packets: [Data], key: SessionKey) {
-        bytesIn += packets.flatCount
+        bytesCount.inbound += packets.flatCount
         do {
             guard let decryptedPackets = try key.decrypt(packets: packets) else {
                 log.warning("Could not decrypt packets, is SessionKey properly configured (dataPath, peerId)?")
@@ -1118,7 +1103,7 @@ public class SessionProxy {
             }
             
             // WARNING: runs in Network.framework queue
-            bytesOut += encryptedPackets.flatCount
+            bytesCount.outbound += encryptedPackets.flatCount
             link?.writePackets(encryptedPackets) { [weak self] (error) in
                 if let error = error {
                     self?.queue.sync {
@@ -1151,9 +1136,9 @@ public class SessionProxy {
         }
         
         // drop queued out packets if ack-ed
-        for (i, controlPacket) in controlQueueOut.enumerated() {
+        for (i, controlPacket) in controlQueue.outbound.enumerated() {
             if packetIds.contains(controlPacket.packetId) {
-                controlQueueOut.remove(at: i)
+                controlQueue.outbound.remove(at: i)
             }
         }