Implement device linking message receiving

Signal/src/Loki/DeviceLinkingModal.swift

@@ -5,10 +5,6 @@ import NVActivityIndicatorView
 @objc(LKDeviceLinkingModal)
 final class DeviceLinkingModal : UIViewController, LokiDeviceLinkingSessionDelegate {
     
-    private lazy var deviceLinkingSession: LokiDeviceLinkingSession = {
-        return LokiDeviceLinkingSession(delegate: self)
-    }()
-    
     // MARK: Components
     private lazy var contentView: UIView = {
         let result = UIView()
@@ -55,7 +51,7 @@ final class DeviceLinkingModal : UIViewController, LokiDeviceLinkingSessionDeleg
     override func viewDidLoad() {
         super.viewDidLoad()
         setUpViewHierarchy()
-        deviceLinkingSession.startListeningForLinkingRequests()
+        LokiDeviceLinkingSession.startListeningForLinkingRequests(with: self)
     }
     
     private func setUpViewHierarchy() {
@@ -109,7 +105,7 @@ final class DeviceLinkingModal : UIViewController, LokiDeviceLinkingSessionDeleg
     }
     
     @objc private func cancel() {
-        deviceLinkingSession.stopListeningForLinkingRequests()
+        LokiDeviceLinkingSession.current?.stopListeningForLinkingRequests()
         dismiss(animated: true, completion: nil)
     }
 }

SignalServiceKit/src/Loki/API/Multi Device/LokiDeviceLinkingSession.swift

@@ -6,13 +6,18 @@ public final class LokiDeviceLinkingSession : NSObject {
     @objc public var isListeningForLinkingRequests = false
     
     // MARK: Lifecycle
-    @objc public init(delegate: LokiDeviceLinkingSessionDelegate) {
+    @objc public static var current: LokiDeviceLinkingSession?
+    
+    private init(delegate: LokiDeviceLinkingSessionDelegate) {
         self.delegate = delegate
     }
 
     // MARK: Public API
-    @objc public func startListeningForLinkingRequests() {
-        isListeningForLinkingRequests = true
+    public static func startListeningForLinkingRequests(with delegate: LokiDeviceLinkingSessionDelegate) -> LokiDeviceLinkingSession {
+        let session = LokiDeviceLinkingSession(delegate: delegate)
+        session.isListeningForLinkingRequests = true
+        LokiDeviceLinkingSession.current = session
+        return session
     }
     
     @objc public func processLinkingRequest(from slaveHexEncodedPublicKey: String, with slaveSignature: Data) {
@@ -25,11 +30,12 @@ public final class LokiDeviceLinkingSession : NSObject {
         delegate.requestUserAuthorization(for: deviceLink)
     }
     
-    @objc public func stopListeningForLinkingRequests() {
+    public func stopListeningForLinkingRequests() {
+        LokiDeviceLinkingSession.current = nil
         isListeningForLinkingRequests = false
     }
     
-    @objc public func authorizeDeviceLink(_ deviceLink: LokiDeviceLink) {
+    public func authorizeDeviceLink(_ deviceLink: LokiDeviceLink) {
         // TODO: Send a device link authorized message
     }
     

SignalServiceKit/src/Messages/OWSMessageManager.m

@@ -417,7 +417,7 @@ NS_ASSUME_NONNULL_BEGIN
     // Loki: Handle friend request acceptance if needed
     // TODO: We'll need to fix this up if we ever start using sync messages
     [self handleFriendRequestAcceptanceIfNeededWithEnvelope:envelope transaction:transaction];
-
+    
     if (envelope.content != nil) {
         NSError *error;
         SSKProtoContent *_Nullable contentProto = [SSKProtoContent parseData:plaintextData error:&error];
@@ -427,17 +427,27 @@ NS_ASSUME_NONNULL_BEGIN
         }
         OWSLogInfo(@"handling content: <Content: %@>", [self descriptionForContent:contentProto]);
         
+        // Loki: Handle device linking message
+        if (contentProto.lokiDeviceLinkingMessage != nil) {
+            OWSLogInfo(@"[Loki] Received a device linking request from: %@", envelope.source);
+            NSData *signature = [contentProto.lokiDeviceLinkingMessage.slaveSignature];
+            if (signature == nil) {
+                OWSFailDebug(@"Received a device linking request without an attached slave signature.");
+            }
+            [LKDeviceLinkingSession.current processLinkingRequestFrom:envelope.source with:signature];
+        }
+        
         // Loki: Handle pre key bundle message
         if (contentProto.prekeyBundleMessage) {
-            OWSLogInfo(@"Received a pre key bundle message from: %@.", envelope.source);
+            OWSLogInfo(@"[Loki] Received a pre key bundle message from: %@.", envelope.source);
             PreKeyBundle *_Nullable bundle = [contentProto.prekeyBundleMessage createPreKeyBundleWithTransaction:transaction];
             if (!bundle) {
-                OWSFailDebug(@"Failed to create PreKeyBundle from message.");
+                OWSFailDebug(@"Failed to create a pre key bundle.");
             }
             [self.primaryStorage setPreKeyBundle:bundle forContact:envelope.source transaction:transaction];
         }
         
-        // Loki: Check if we got p2p address
+        // Loki: Check if we got a P2P address
         if (contentProto.lokiAddressMessage) {
             NSString *address = contentProto.lokiAddressMessage.ptpAddress;
             uint32_t port = contentProto.lokiAddressMessage.ptpPort;
@@ -1572,6 +1582,10 @@ NS_ASSUME_NONNULL_BEGIN
     }
 }
 
+- (void)handleDeviceLinkingMessageIfNeeded:(TSIncomingMessage *)message transaction:(YapDatabaseReadWriteTransaction *)transaction {
+    
+}
+
 - (void)finalizeIncomingMessage:(TSIncomingMessage *)incomingMessage
                          thread:(TSThread *)thread
                        envelope:(SSKProtoEnvelope *)envelope