Use device ID to distinguish remotes

Sesame/API/Message.swift

@@ -50,14 +50,17 @@ extension Message {
         /// The counter of the message (for freshness)
         let id: UInt32
         
+        let deviceId: UInt8?
+
         /**
          Create new message content.
          - Parameter time: The time of message creation,
          - Parameter id: The counter of the message
          */
-        init(time: UInt32, id: UInt32) {
+        init(time: UInt32, id: UInt32, device: UInt8) {
             self.time = time
             self.id = id
+            self.deviceId = device
         }
 
         /**
@@ -69,17 +72,18 @@ extension Message {
          */
         init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
             self.time = UInt32(data: Data(data.prefix(MemoryLayout<UInt32>.size)))
-            self.id = UInt32(data: Data(data.dropFirst(MemoryLayout<UInt32>.size)))
+            self.id = UInt32(data: Data(data.dropLast().suffix(MemoryLayout<UInt32>.size)))
+            self.deviceId = data.suffix(1).last!
         }
 
         /// The byte length of an encoded message content
         static var length: Int {
-            MemoryLayout<UInt32>.size * 2
+            MemoryLayout<UInt32>.size * 2 + 1
         }
 
         /// The message content encoded to data
         var encoded: Data {
-            time.encoded + id.encoded
+            time.encoded + id.encoded + Data([deviceId ?? 0])
         }
     }
 }
@@ -89,6 +93,7 @@ extension Message.Content: Codable {
     enum CodingKeys: Int, CodingKey {
         case time = 1
         case id = 2
+        case deviceId = 3
     }
 }
 

Sesame/API/MessageResult.swift

@@ -26,6 +26,9 @@ enum MessageResult: UInt8 {
     /// The key was accepted by the device, and the door will be opened
     case messageAccepted = 7
     
+    /// The device id is invalid
+    case messageDeviceInvalid = 8
+
 
     /// The request did not contain body data with the key
     case noBodyData = 10
@@ -61,6 +64,8 @@ extension MessageResult: CustomStringConvertible {
             return "Message counter invalid"
         case .messageAccepted:
             return "Message accepted"
+        case .messageDeviceInvalid:
+            return "Invalid device ID"
         case .noBodyData:
             return "No body data included in the request"
         case .deviceNotConnected:

Sesame/ClientState.swift

@@ -19,6 +19,7 @@ extension ConnectionError: CustomStringConvertible {
 }
 
 enum RejectionCause {
+    case invalidDeviceId
     case invalidCounter
     case invalidTime
     case invalidAuthentication
@@ -30,6 +31,8 @@ extension RejectionCause: CustomStringConvertible {
 
     var description: String {
         switch self {
+        case .invalidDeviceId:
+            return "Invalid device ID"
         case .invalidCounter:
             return "Invalid counter"
         case .invalidTime:
@@ -92,6 +95,8 @@ enum ClientState {
             self = .messageRejected(.timeout)
         case .messageAccepted:
             self = .openSesame
+        case .messageDeviceInvalid:
+            self = .messageRejected(.invalidDeviceId)
         case .noBodyData, .invalidMessageData, .textReceived, .unexpectedSocketEvent:
             self = .internalError(keyResult.description)
         case .deviceNotConnected:
@@ -207,6 +212,8 @@ extension ClientState {
             return 6
         case .messageRejected(let rejectionCause):
             switch rejectionCause {
+            case .invalidDeviceId:
+                return 19
             case .invalidCounter:
                 return 7
             case .invalidTime:
@@ -230,6 +237,8 @@ extension ClientState {
                 return 15
             case .missingKey:
                 return 16
+            case .invalidDeviceId:
+                return 20
             }
         case .openSesame:
             return 17
@@ -276,6 +285,10 @@ extension ClientState {
             self = .openSesame
         case 18:
             self = .internalError("")
+        case 19:
+            self = .messageRejected(.invalidDeviceId)
+        case 20:
+            self = .responseRejected(.invalidDeviceId)
         default:
             self = .internalError("Unknown code \(code)")
         }

Sesame/ContentView.swift

@@ -18,6 +18,9 @@ struct ContentView: View {
     @AppStorage("local")
     private var useLocalConnection = false
     
+    @AppStorage("deviceID")
+    private var deviceID: Int = 0
+
     @State
     var keyManager = KeyManagement()
 
@@ -133,6 +136,8 @@ struct ContentView: View {
                     keyManager: $keyManager,
                     serverAddress: $serverPath,
                     localAddress: $localAddress,
+                    deviceID: $deviceID,
+                    nextMessageCounter: $nextMessageCounter,
                     isCompensatingDaylightTime: $isCompensatingDaylightTime,
                     useLocalConnection: $useLocalConnection)
             }
@@ -145,7 +150,8 @@ struct ContentView: View {
     
     func mainButtonPressed() {
         guard let key = keyManager.get(.remoteKey),
-              let token = keyManager.get(.authToken)?.data else {
+              let token = keyManager.get(.authToken)?.data,
+              let deviceId = UInt8(exactly: deviceID) else {
             return
         }
 
@@ -154,7 +160,8 @@ struct ContentView: View {
         // Add time to compensate that the device is using daylight savings time
         let content = Message.Content(
             time: sentTime.timestamp + compensationTime,
-            id: count)
+            id: count,
+            device: deviceId)
         let message = content.authenticate(using: key)
         let historyItem = HistoryItem(sent: message.content, date: sentTime, local: useLocalConnection)
         state = .waitingForResponse

Sesame/HistoryItem.swift

@@ -123,8 +123,8 @@ extension HistoryItem: Comparable {
 extension HistoryItem {
 
     static var mock: HistoryItem {
-        let content = Message.Content(time: Date.now.timestamp, id: 123)
+        let content = Message.Content(time: Date.now.timestamp, id: 123, device: 0)
-        let content2 = Message.Content(time: (Date.now + 1).timestamp, id: 124)
+        let content2 = Message.Content(time: (Date.now + 1).timestamp, id: 124, device: 0)
         return .init(sent: content, date: .now, local: false)
             .didReceive(response: .openSesame, date: .now + 2, message: content2)
     }

Sesame/KeyManagement.swift

@@ -17,11 +17,11 @@ extension KeyManagement {
         var displayName: String {
             switch self {
             case .deviceKey:
-                return "Device Key"
+                return "Unlock Key"
             case .remoteKey:
-                return "Remote Key"
+                return "Response Key"
             case .authToken:
-                return "Authentication Token"
+                return "Server Token"
             }
         }
 
@@ -148,6 +148,15 @@ final class KeyManagement: ObservableObject {
 
     func generate(_ type: KeyType) {
         let key = SymmetricKey(size: type.keyLength)
+        save(type, key: key)
+    }
+    
+    func save(_ type: KeyType, data: Data) {
+        let key = SymmetricKey(data: data)
+        save(type, key: key)
+    }
+    
+    private func save(_ type: KeyType, key: SymmetricKey) {
         if keyChain.has(type) {
             keyChain.delete(type)
         }

Sesame/SettingsView.swift

@@ -11,12 +11,31 @@ struct SettingsView: View {
     @Binding
     var localAddress: String
     
+    @Binding
+    var deviceID: Int
+    
+    @Binding
+    var nextMessageCounter: Int
+
     @Binding
     var isCompensatingDaylightTime: Bool
     
     @Binding
     var useLocalConnection: Bool
     
+    @State
+    private var showDeviceIdInput = false
+    
+    @State
+    private var deviceIdText = ""
+    
+    @State
+    private var showCounterInput = false
+    
+    @State
+    private var counterText = ""
+    
+    
     var body: some View {
         NavigationView {
             ScrollView {
@@ -25,12 +44,14 @@ struct SettingsView: View {
                         Text("Server address")
                             .bold()
                         TextField("Server address", text: $serverAddress)
+                            .foregroundColor(.secondary)
                             .padding(.leading, 8)
                     }.padding(.vertical, 8)
                     VStack(alignment: .leading) {
                         Text("Local address")
                             .bold()
                         TextField("Local address", text: $localAddress)
+                            .foregroundColor(.secondary)
                             .padding(.leading, 8)
                     }.padding(.vertical, 8)
                     Toggle(isOn: $useLocalConnection) {
@@ -39,6 +60,32 @@ struct SettingsView: View {
                     Text("Attempt to communicate directly with the device. This is useful if the server is unavailable. Requires a WiFi connection on the same network as the device.")
                         .font(.caption)
                         .foregroundColor(.secondary)
+                    VStack(alignment: .leading) {
+                        Text("Device id")
+                            .bold()
+                        HStack(alignment: .bottom) {
+                            Text("\(deviceID)")
+                                .font(.system(.body, design: .monospaced))
+                                .foregroundColor(.secondary)
+                                .padding([.trailing, .bottom])
+                            Button("Edit", action: showAlertToChangeDeviceID)
+                                .padding([.horizontal, .bottom])
+                                .padding(.top, 4)
+                        }
+                    }.padding(.vertical, 8)
+                    VStack(alignment: .leading) {
+                        Text("Message counter")
+                            .bold()
+                        HStack(alignment: .bottom) {
+                            Text("\(nextMessageCounter)")
+                                .font(.system(.body, design: .monospaced))
+                                .foregroundColor(.secondary)
+                                .padding([.trailing, .bottom])
+                            Button("Edit", action: showAlertToChangeCounter)
+                                .padding([.horizontal, .bottom])
+                                .padding(.top, 4)
+                        }
+                    }.padding(.vertical, 8)
                     ForEach(KeyManagement.KeyType.allCases) { keyType in
                         SingleKeyView(
                             keyManager: $keyManager,
@@ -57,8 +104,54 @@ struct SettingsView: View {
                 }
             }
             .navigationTitle("Settings")
+            .alert("Update device ID", isPresented: $showDeviceIdInput, actions: {
+                TextField("Device ID", text: $deviceIdText)
+                    .keyboardType(.decimalPad)
+                    .font(.system(.body, design: .monospaced))
+                    .foregroundColor(.black)
+                Button("Save", action: saveDeviceID)
+                Button("Cancel", role: .cancel, action: {})
+            }, message: {
+                Text("Enter the device ID")
+            })
+            .alert("Update message counter", isPresented: $showCounterInput, actions: {
+                TextField("Message counter", text: $counterText)
+                    .keyboardType(.decimalPad)
+                    .font(.system(.body, design: .monospaced))
+                    .foregroundColor(.black)
+                Button("Save", action: saveCounter)
+                Button("Cancel", role: .cancel, action: {})
+            }, message: {
+                Text("Enter the message counter")
+            })
         }
     }
+    
+    private func showAlertToChangeDeviceID() {
+        deviceIdText = "\(deviceID)"
+        showDeviceIdInput = true
+    }
+    
+    private func saveDeviceID() {
+        guard let id = UInt8(deviceIdText) else {
+            print("Invalid device id '\(deviceIdText)'")
+            return
+        }
+        self.deviceID = Int(id)
+    }
+    
+    private func showAlertToChangeCounter() {
+        counterText = "\(nextMessageCounter)"
+        showCounterInput = true
+    }
+    
+    private func saveCounter() {
+        guard let id = UInt32(counterText) else {
+            print("Invalid message counter '\(counterText)'")
+            return
+        }
+        self.nextMessageCounter = Int(id)
+    }
 }
 
 struct SettingsView_Previews: PreviewProvider {
@@ -67,6 +160,8 @@ struct SettingsView_Previews: PreviewProvider {
             keyManager: .constant(KeyManagement()),
             serverAddress: .constant("https://example.com"),
             localAddress: .constant("192.168.178.42"),
+            deviceID: .constant(0),
+            nextMessageCounter: .constant(12345678),
             isCompensatingDaylightTime: .constant(true),
             useLocalConnection: .constant(false))
     }

Sesame/SingleKeyView.swift

@@ -9,6 +9,12 @@ struct SingleKeyView: View {
     @Binding
     var keyManager: KeyManagement
     
+    @State
+    private var showEditWindow = false
+    
+    @State
+    private var keyText = ""
+
     let type: KeyManagement.KeyType
 
     private var generateText: String {
@@ -54,9 +60,41 @@ struct SingleKeyView: View {
                 .disabled(!hasKey)
                 .padding([.horizontal, .bottom])
                 .padding(.top, 4)
+                Button("Edit") {
+                    keyText = keyManager.get(type)?.displayString ?? ""
+                    print("Set key text to '\(keyText)'")
+                    showEditWindow = true
+                }
+                .padding([.horizontal, .bottom])
+                .padding(.top, 4)
                 Spacer()
             }
         }
+        .alert("Update key", isPresented: $showEditWindow, actions: {
+            TextField("Key data", text: $keyText)
+                .lineLimit(4)
+                .font(.system(.body, design: .monospaced))
+                .foregroundColor(.black)
+            Button("Save", action: saveKey)
+            Button("Cancel", role: .cancel, action: {})
+        }, message: {
+            Text("Enter the hex encoded key")
+        })
+    }
+    
+    private func saveKey() {
+        let cleanText = keyText.replacingOccurrences(of: " ", with: "")
+        guard let keyData = Data(fromHexEncodedString: cleanText) else {
+            print("Invalid key string")
+            return
+        }
+        let keyLength = type.keyLength.bitCount
+        guard keyData.count * 8 == keyLength else {
+            print("Invalid key length \(keyData.count * 8) bits, expected \(keyLength)")
+            return
+        }
+        keyManager.save(type, data: keyData)
+        print("Key \(type) saved")
     }
 }
 
@@ -65,5 +103,6 @@ struct SingleKeyView_Previews: PreviewProvider {
         SingleKeyView(
             keyManager: .constant(KeyManagement()),
             type: .deviceKey)
+        .previewLayout(.fixed(width: 350, height: 100))
     }
 }