Simplify unlock logic, don't spam challenges

This commit is contained in:
Christoph Hagen 2023-12-12 23:46:51 +01:00
parent 941aebd9ca
commit b749a80f5d
3 changed files with 80 additions and 129 deletions

View File

@ -24,6 +24,13 @@ struct ContentView: View {
.white
}
private var stateText: String {
if coordinator.state == .notChecked {
return "Unlock"
}
return coordinator.state.description
}
var body: some View {
HStack {
Spacer()
@ -39,7 +46,7 @@ struct ContentView: View {
.progressViewStyle(CircularProgressViewStyle())
.frame(width: 20, height: 20)
} else {
Text("Unlock")
Text(stateText)
.font(.subheadline)
}
}

View File

@ -4,15 +4,9 @@ import SwiftData
final class RequestCoordinator: ObservableObject {
@Published
var serverChallenge: ServerChallenge? = nil
@Published
var state: MessageResult = .noKeyAvailable
@Published
private var timer: Timer?
@Published
var pendingRequests: [PendingOperation] = []
@ -22,6 +16,9 @@ final class RequestCoordinator: ObservableObject {
@Published
var keyManager = KeyManagement()
@Published
var isPerformingRequest: Bool = false
@AppStorage("server")
var serverPath: String = "https://christophhagen.de/sesame/"
@ -31,7 +28,11 @@ final class RequestCoordinator: ObservableObject {
@AppStorage("connectionType")
var connectionType: ConnectionStrategy = .remoteFirst
let modelContext: ModelContext
private let modelContext: ModelContext
private let client = Client()
private var timer: Timer?
init(modelContext: ModelContext) {
self.modelContext = modelContext
@ -40,151 +41,97 @@ final class RequestCoordinator: ObservableObject {
}
}
let client = Client()
var needsNewServerChallenge: Bool {
serverChallenge?.isExpired ?? true
}
@Published
var isPerformingRequest: Bool = false
func startUnlock() {
addOperations(.challenge, .unlock)
}
func startChallenge() {
addOperations(.challenge)
}
private func addOperations(_ operations: RequestType...) {
#warning("Only perform challenge when doing unlock? Remove code complexity")
// Just add all operations for an unlock
// For every completed operation, the unnecessary ones will be removed without executing them
let operations = connectionType.transmissionTypes.map { route in
operations.map { PendingOperation(route: route, operation: $0) }
}.joined()
pendingRequests.append(contentsOf: operations)
continueRequests()
}
private func continueRequests() {
guard activeRequest == nil else {
guard !isPerformingRequest else {
return
}
guard !pendingRequests.isEmpty else {
self.isPerformingRequest = false
return
}
let activeRequest = pendingRequests.removeFirst()
self.activeRequest = activeRequest
self.isPerformingRequest = true
isPerformingRequest = true
Task {
await process(request: activeRequest)
let finalResult = await performFullChallengeResponse()
DispatchQueue.main.async {
self.state = finalResult
self.isPerformingRequest = false
}
scheduleReturnToReadyState()
}
}
private func process(request: PendingOperation) async {
private func performFullChallengeResponse() async -> MessageResult {
let transmissionTypes = connectionType.transmissionTypes
for route in transmissionTypes.dropLast() {
if await performUnlockAndSaveItem(route: route) == .unlocked {
return .unlocked
}
}
guard let route = transmissionTypes.last else {
// No transmission types at all
return keyManager.hasAllKeys ? .notChecked : .noKeyAvailable
}
return await performUnlockAndSaveItem(route: route)
}
private func performUnlockAndSaveItem(route: TransmissionType) async -> MessageResult {
let startTime = Date.now
let (success, response, challenge) = await self.start(request)
let result = await performFullChallengeResponse(route: route)
let endTime = Date.now
let roundTripTime = endTime.timeIntervalSince(startTime)
if let s = challenge?.message {
print("\(s) took \(Int(roundTripTime * 1000)) ms")
} else {
print("\(request.operation.description) took \(Int(roundTripTime * 1000)) ms")
print("Unlock took \(Int(roundTripTime * 1000)) ms (\(result.result))")
let item = HistoryItem(message: result, startDate: startTime, route: route, finishDate: endTime)
modelContext.insert(item)
return result.result
}
private func performFullChallengeResponse(route: TransmissionType) async -> Message {
let (challengeResponse, challenge) = await performChallenge(route: route)
guard let challenge else {
return challengeResponse
}
if request.operation == .unlock, let response {
print("Saving history item")
let item = HistoryItem(message: response, startDate: startTime, route: request.route, finishDate: endTime)
modelContext.insert(item)
}
DispatchQueue.main.async {
self.filterPendingRequests(after: request, success: success, hasChallenge: challenge != nil)
if let response {
self.state = response.result
}
if let challenge {
self.serverChallenge = challenge
}
self.activeRequest = nil
self.continueRequests()
let (unlockResponse, secondaryChallenge) = await performUnlock(with: challenge.message, route: route)
guard let secondaryChallenge else {
return unlockResponse
}
let (secondUnlockResponse, _) = await performUnlock(with: secondaryChallenge.message, route: route)
return secondUnlockResponse
}
private func filterPendingRequests(after operation: PendingOperation, success: Bool, hasChallenge: Bool) {
if success {
// Filter all unlocks
if operation.operation == .unlock {
// Successful unlock means no need for next challenge or unlocks, so remove all
self.pendingRequests = []
} else {
// Successful challenge means no need for additional challenges, but keep unlocks
self.pendingRequests = pendingRequests.filter { $0.operation != .challenge }
}
} else {
// Filter all operations with the same route for connection errors
// And with type, depending on error?
}
}
private func start(_ operation: PendingOperation) async -> OptionalServerResponse {
switch operation.operation {
case .challenge:
if let serverChallenge, !serverChallenge.isExpired {
return (true, serverChallenge.message, serverChallenge)
}
return await performChallenge(route: operation.route)
case .unlock:
guard let serverChallenge, !serverChallenge.isExpired else {
return (false, nil, nil)
}
return await performUnlock(with: serverChallenge.message, route: operation.route)
}
}
private func performChallenge(route: TransmissionType) async -> OptionalServerResponse {
private func performChallenge(route: TransmissionType) async -> ServerResponse {
let initialMessage = Message.initial()
let (result, challenge) = await send(initialMessage, route: route)
guard let message = challenge?.message else {
return (false, result, nil)
return (result, nil)
}
// Can't get here without the message being accepted
guard message.messageType == .challenge else {
print("Invalid message type for challenge: \(message)")
return (false, result.with(result: .invalidMessageTypeFromDevice), nil)
return (result.with(result: .invalidMessageTypeFromDevice), nil)
}
return (true, result.with(result: .deviceAvailable), challenge)
return (result.with(result: .deviceAvailable), challenge)
}
private func performUnlock(with challenge: Message, route: TransmissionType) async -> OptionalServerResponse {
private func performUnlock(with challenge: Message, route: TransmissionType) async -> ServerResponse {
let request = challenge.requestMessage()
let (unlockState, responseData) = await send(request, route: route)
guard let response = responseData?.message else {
return (false, unlockState, nil)
return (unlockState, nil)
}
switch response.messageType {
case .initial, .request:
print("Invalid message type for response: \(response)")
return (false, response.with(result: .invalidMessageTypeFromDevice), nil)
return (response.with(result: .invalidMessageTypeFromDevice), nil)
case .challenge:
// New challenge received, challenge was expired
return (true, unlockState, responseData)
return (unlockState, responseData)
case .response:
break
}
guard response.serverChallenge == request.serverChallenge else {
print("Invalid server challenge for unlock: \(response)")
return (false, response.with(result: .invalidServerChallengeFromDevice), nil)
return (response.with(result: .invalidServerChallengeFromDevice), nil)
}
return (true, response.with(result: .unlocked), nil)
return (response.with(result: .unlocked), nil)
}
private func url(for route: TransmissionType) -> String {
@ -203,27 +150,26 @@ final class RequestCoordinator: ObservableObject {
let url = url(for: route)
return await client.send(message, to: url, through: route, using: keys)
}
func startUpdatingServerChallenge() {
guard timer == nil else {
return
}
func resetState() {
let hasKeys = keyManager.hasAllKeys
DispatchQueue.main.async {
self.timer = Timer.scheduledTimer(withTimeInterval: 3, repeats: true) { [weak self] timer in
self.state = hasKeys ? .notChecked : .noKeyAvailable
}
}
func scheduleReturnToReadyState() {
timer?.invalidate()
DispatchQueue.main.async {
self.timer = Timer.scheduledTimer(withTimeInterval: 3, repeats: false) { [weak self] timer in
defer { timer.invalidate() }
guard let self else {
timer.invalidate()
return
}
DispatchQueue.main.async {
self.startChallenge()
}
self.resetState()
self.timer = nil
}
self.timer!.fire()
}
}
func endUpdatingServerChallenge() {
timer?.invalidate()
timer = nil
}
}

View File

@ -65,8 +65,6 @@ struct ContentView: View {
.padding(.horizontal, 30)
}
.background(coordinator.state.color)
.onAppear(perform: coordinator.startUpdatingServerChallenge)
.onDisappear(perform: coordinator.endUpdatingServerChallenge)
.animation(.easeInOut, value: coordinator.state.color)
.sheet(isPresented: $showSettingsSheet) {
SettingsView(