Started working on `MessageRequestResponse` handling for SOGS message requests

Pointing Curve25519 to use a fork that exposes an XEd25519 conversion method
Fixed an issue where I had broken all message sending due to the SnodeAPI casting Onion responses to `Any`

Podfile

@@ -24,7 +24,8 @@ abstract_target 'GlobalDependencies' do
   
   # Dependencies to be included only in all extensions/frameworks
   abstract_target 'FrameworkAndExtensionDependencies' do
-    pod 'Curve25519Kit', git: 'https://github.com/signalapp/Curve25519Kit.git'
+    # TODO: Swap this to use an oxen-io fork
+    pod 'Curve25519Kit', git: 'https://github.com/mpretty-cyro/session-ios-curve-25519-kit.git', branch: 'session'
     pod 'SignalCoreKit', git: 'https://github.com/oxen-io/session-ios-core-kit', branch: 'session-version'
     
     target 'SessionNotificationServiceExtension'

Podfile.lock

@@ -123,7 +123,7 @@ PODS:
 DEPENDENCIES:
   - AFNetworking
   - CryptoSwift
-  - Curve25519Kit (from `https://github.com/signalapp/Curve25519Kit.git`)
+  - Curve25519Kit (from `https://github.com/mpretty-cyro/session-ios-curve-25519-kit.git`, branch `session`)
   - Mantle (from `https://github.com/signalapp/Mantle`, branch `signal-master`)
   - Nimble
   - NVActivityIndicatorView
@@ -156,7 +156,8 @@ SPEC REPOS:
 
 EXTERNAL SOURCES:
   Curve25519Kit:
-    :git: https://github.com/signalapp/Curve25519Kit.git
+    :branch: session
+    :git: https://github.com/mpretty-cyro/session-ios-curve-25519-kit.git
   Mantle:
     :branch: signal-master
     :git: https://github.com/signalapp/Mantle
@@ -174,8 +175,8 @@ EXTERNAL SOURCES:
 
 CHECKOUT OPTIONS:
   Curve25519Kit:
-    :commit: 4fc1c10e98fff2534b5379a9bb587430fdb8e577
+    :commit: a23049232dc6c18928cdacfbcef287dad954c5c6
-    :git: https://github.com/signalapp/Curve25519Kit.git
+    :git: https://github.com/mpretty-cyro/session-ios-curve-25519-kit.git
   Mantle:
     :commit: e7e46253bb01ce39525d90aa69ed9e85e758bfc4
     :git: https://github.com/signalapp/Mantle
@@ -213,6 +214,6 @@ SPEC CHECKSUMS:
   YYImage: f1ddd15ac032a58b78bbed1e012b50302d318331
   ZXingObjC: fdbb269f25dd2032da343e06f10224d62f537bdb
 
-PODFILE CHECKSUM: 42874150fd08761ee6907c5bacf22b95ae849d8c
+PODFILE CHECKSUM: b3b9b5446a109dbcdb5381176ebe431f7762558d
 
 COCOAPODS: 1.11.2

SessionMessagingKit/Database/Storage+Messaging.swift

@@ -2,6 +2,34 @@ import PromiseKit
 import Sodium
 
 extension Storage {
+    
+    public func getAllMessageRequestThreads() -> [String: TSContactThread] {
+        var result: [String: TSContactThread] = [:]
+        
+        Storage.read { transaction in
+            result = self.getAllMessageRequestThreads(using: transaction)
+        }
+        
+        return result
+    }
+    
+    public func getAllMessageRequestThreads(using transaction: YapDatabaseReadTransaction) -> [String: TSContactThread] {
+        var result = [String: TSContactThread]()
+        
+        // FIXME: We might be able to optimise this further by filtering the SQL query `WHERE uniqueId LIKE '_c15'
+        let blindedThreadPrefix: String = TSContactThread.threadID(fromContactSessionID: SessionId.Prefix.blinded.rawValue)
+        
+        transaction.enumerateKeysAndObjects(
+            inCollection: TSContactThread.collection(),
+            using: { threadID, object, _ in
+                guard let contactThread = object as? TSContactThread else { return }
+                result[threadID] = contactThread
+            },
+            withFilter: { key -> Bool in key.starts(with: blindedThreadPrefix) }
+        )
+        
+        return result
+    }
 
     /// Returns the ID of the thread.
     public func getOrCreateThread(for publicKey: String, groupPublicKey: String?, openGroupID: String?, using transaction: Any) -> String? {

SessionMessagingKit/Open Groups/OpenGroupAPI.swift

@@ -115,7 +115,7 @@ public final class OpenGroupAPI: NSObject {
                     // TODO: Limit?
 //                    queryParameters: [ .limit: 256 ]
                 ),
-                responseType: [DirectMessage].self
+                responseType: [DirectMessage]?.self // 'inboxSince' will return a `304` with an empty response if no messages
             )
         )
         
@@ -507,30 +507,30 @@ public final class OpenGroupAPI: NSObject {
     /// method, in order to call this directly remove the `@available` line and make sure to route the response of this method to the
     /// `OpenGroupManager.handleInbox` method to ensure things are processed correctly
     @available(*, unavailable, message: "Avoid using this directly, use the pre-build `poll()` method instead")
-    public static func inbox(on server: String, using dependencies: Dependencies = Dependencies()) -> Promise<(OnionRequestResponseInfoType, [DirectMessage])> {
+    public static func inbox(on server: String, using dependencies: Dependencies = Dependencies()) -> Promise<(OnionRequestResponseInfoType, [DirectMessage]?)> {
         let request: Request = Request<NoBody>(
             server: server,
             endpoint: .inbox
         )
         
         return send(request, using: dependencies)
-            .decoded(as: [DirectMessage].self, on: OpenGroupAPI.workQueue, error: Error.parsingFailed, using: dependencies)
+            .decoded(as: [DirectMessage]?.self, on: OpenGroupAPI.workQueue, error: Error.parsingFailed, using: dependencies)
     }
     
-    /// Polls for any DMs received since the given id
+    /// Polls for any DMs received since the given id, this method will return a `304` with an empty response if there are no messages
     ///
     /// **Note:** This is the direct request to retrieve messages requests for a specific Open Group since a given messages so should be retrieved
     /// automatically from the `poll()` method, in order to call this directly remove the `@available` line and make sure to route the response
     /// of this method to the `OpenGroupManager.handleInbox` method to ensure things are processed correctly
     @available(*, unavailable, message: "Avoid using this directly, use the pre-build `poll()` method instead")
-    public static func inboxSince(id: Int64, on server: String, using dependencies: Dependencies = Dependencies()) -> Promise<(OnionRequestResponseInfoType, [DirectMessage])> {
+    public static func inboxSince(id: Int64, on server: String, using dependencies: Dependencies = Dependencies()) -> Promise<(OnionRequestResponseInfoType, [DirectMessage]?)> {
         let request: Request = Request<NoBody>(
             server: server,
             endpoint: .inboxSince(id: id)
         )
         
         return send(request, using: dependencies)
-            .decoded(as: [DirectMessage].self, on: OpenGroupAPI.workQueue, error: Error.parsingFailed, using: dependencies)
+            .decoded(as: [DirectMessage]?.self, on: OpenGroupAPI.workQueue, error: Error.parsingFailed, using: dependencies)
     }
     
     /// Delivers a direct message to a user via their blinded Session ID

SessionMessagingKit/Open Groups/OpenGroupManager.swift

@@ -319,6 +319,8 @@ public final class OpenGroupManager: NSObject {
         isBackgroundPoll: Bool,
         using dependencies: OpenGroupAPI.Dependencies = OpenGroupAPI.Dependencies()
     ) {
+        // Don't need to do anything if we have no messages (it's a valid case)
+        guard !messages.isEmpty else { return }
         guard let serverPublicKey: String = dependencies.storage.getOpenGroupPublicKey(for: server) else {
             SNLog("Couldn't receive inbox message.")
             return

SessionMessagingKit/Open Groups/Types/SodiumProtocols.swift

@@ -15,6 +15,8 @@ public protocol SodiumType {
     
     func combineKeys(lhsKeyBytes: Bytes, rhsKeyBytes: Bytes) -> Bytes?
     func sharedBlindedEncryptionKey(secretKey a: Bytes, otherBlindedPublicKey: Bytes, fromBlindedPublicKey kA: Bytes, toBlindedPublicKey kB: Bytes, genericHash: GenericHashType) -> Bytes?
+    
+    func sessionId(_ sessionId: String, matchesBlindedId blindedSessionId: String, serverPublicKey: String) -> Bool
 }
 
 public protocol AeadXChaCha20Poly1305IetfType {

SessionMessagingKit/Sending & Receiving/Pollers/OpenGroupPoller.swift

@@ -124,13 +124,13 @@ extension OpenGroupAPI {
                         )
                         
                     case .inbox, .inboxSince:
-                        guard let responseData: BatchSubResponse<[DirectMessage]> = endpointResponse.data as? BatchSubResponse<[DirectMessage]>, let responseBody: [DirectMessage] = responseData.body else {
+                        guard let responseData: BatchSubResponse<[DirectMessage]?> = endpointResponse.data as? BatchSubResponse<[DirectMessage]?>, let responseBody: [DirectMessage]? = responseData.body else {
                             SNLog("Open group polling failed due to invalid data.")
                             return
                         }
                         
                         OpenGroupManager.handleInbox(
-                            responseBody,
+                            (responseBody ?? []),
                             on: server,
                             isBackgroundPoll: isBackgroundPoll
                         )

SessionMessagingKit/Storage.swift

@@ -80,6 +80,9 @@ public protocol SessionMessagingKitStorageProtocol {
 
     // MARK: - Message Handling
 
+    func getAllMessageRequestThreads() -> [String: TSContactThread]
+    func getAllMessageRequestThreads(using transaction: YapDatabaseReadTransaction) -> [String: TSContactThread]
+    
     func getReceivedMessageTimestamps(using transaction: Any) -> [UInt64]
     func addReceivedMessageTimestamp(_ timestamp: UInt64, using transaction: Any)
     /// Returns the ID of the thread.

SessionMessagingKit/Utilities/Sodium+Utilities.swift

@@ -1,5 +1,6 @@
 import Clibsodium
 import Sodium
+import Curve25519Kit
 
 extension Sign {
 
@@ -232,6 +233,33 @@ extension Sodium {
         
         return genericHash.hash(message: (combinedKeyBytes + kA + kB), outputLength: 32)
     }
+    
+    /// This method should be used to check if a users standard sessionId matches a blinded one
+    public func sessionId(_ standardSessionId: String, matchesBlindedId blindedSessionId: String, serverPublicKey: String) -> Bool {
+        // Only support generating blinded keys for standard session ids
+        guard let sessionId: SessionId = SessionId(from: standardSessionId), sessionId.prefix == .standard else { return false }
+        guard let blindedId: SessionId = SessionId(from: blindedSessionId), blindedId.prefix == .blinded else { return false }
+        guard let kBytes: Bytes = generateBlindingFactor(serverPublicKey: serverPublicKey) else { return false }
+
+        /// From the session id (ignoring 05 prefix) we have two possible ed25519 pubkeys; the first is the positive (which is what
+        /// Signal's XEd25519 conversion always uses)
+        ///
+        /// Note: The below method is code we have exposed from the `curve25519_verify` method within the Curve25519 library
+        /// rather than custom code we have written
+        guard let xEd25519Key: Data = try? Ed25519.publicKey(from: Data(hex: sessionId.publicKey)) else { return false }
+        
+        /// Blind the positive public key
+        guard let pk1: Bytes = combineKeys(lhsKeyBytes: kBytes, rhsKeyBytes: xEd25519Key.bytes) else { return false }
+        
+        /// For the negative, what we're going to get out of the above is simply the negative of pk1, so flip the sign bit to get pk2
+        ///     pk2 = pk1[0:31] + bytes([pk1[31] ^ 0b1000_0000])
+        let pk2: Bytes = (pk1[0..<31] + [(pk1[31] ^ 0b1000_0000)])
+        
+        return (
+            SessionId(.blinded, publicKey: pk1).publicKey == blindedId.publicKey ||
+            SessionId(.blinded, publicKey: pk2).publicKey == blindedId.publicKey
+        )
+    }
 }
 
 extension GenericHash {

SessionSnodeKit/OnionRequestAPI+Encryption.swift

@@ -14,44 +14,28 @@ internal extension OnionRequestAPI {
     }
 
     /// Encrypts `payload` for `destination` and returns the result. Use this to build the core of an onion request.
-    static func encrypt(_ payload: String, for destination: Destination) -> Promise<AESGCM.EncryptionResult> {
+    static func encrypt(_ payload: String, for destination: Destination, with version: Version) -> Promise<AESGCM.EncryptionResult> {
         let (promise, seal) = Promise<AESGCM.EncryptionResult>.pending()
         DispatchQueue.global(qos: .userInitiated).async {
             do {
-                guard let data = payload.data(using: .utf8) else {
+                guard let payloadAsData: Data = payload.data(using: .utf8) else { throw Error.invalidRequestInfo }
-                    throw Error.invalidRequestInfo
-                }
                 
-                let result = try encrypt(data, for: destination)
+                let data: Data
-                seal.fulfill(result)
-            }
-            catch (let error) {
-                seal.reject(error)
-            }
-        }
-        
-        return promise
-    }
-    
-    static func encrypt(_ payload: JSON, for destination: Destination) -> Promise<AESGCM.EncryptionResult> {
-        let (promise, seal) = Promise<AESGCM.EncryptionResult>.pending()
-        DispatchQueue.global(qos: .userInitiated).async {
-            do {
-                guard JSONSerialization.isValidJSONObject(payload) else { return seal.reject(HTTP.Error.invalidJSON) }
                 
-                // Wrapping isn't needed for file server or open group onion requests
+                switch version {
-                switch destination {
+                    case .v2, .v3:
-                    case .snode:
+                        // Wrapping is only needed for snode requests
-                        let payloadAsData = try JSONSerialization.data(withJSONObject: payload, options: [ .fragmentsAllowed ])
+                        switch destination {
-                        let data = try encode(ciphertext: payloadAsData, json: [ "headers" : "" ])
+                            case .snode: data = try encode(ciphertext: payloadAsData, json: [ "headers" : "" ])
-                        let result = try encrypt(data, for: destination)
+                            case .server: data = payloadAsData
-                        seal.fulfill(result)
+                        }
                         
-                    case .server:
+                    case .v4:
-                        let data = try JSONSerialization.data(withJSONObject: payload, options: [ .fragmentsAllowed ])
+                        data = payloadAsData
-                        let result = try encrypt(data, for: destination)
-                        seal.fulfill(result)
                 }
+                
+                let result = try encrypt(data, for: destination)
+                seal.fulfill(result)
             }
             catch (let error) {
                 seal.reject(error)

SessionSnodeKit/OnionRequestAPI.swift

@@ -245,7 +245,7 @@ public enum OnionRequestAPI: OnionRequestAPIType {
     }
 
     /// Builds an onion around `payload` and returns the result.
-    private static func buildOnion(around payload: String, targetedAt destination: Destination) -> Promise<OnionBuildingResult> {
+    private static func buildOnion(around payload: String, targetedAt destination: Destination, version: Version) -> Promise<OnionBuildingResult> {
         var guardSnode: Snode!
         var targetSnodeSymmetricKey: Data! // Needed by invoke(_:on:with:) to decrypt the response sent back by the destination
         var encryptionResult: AESGCM.EncryptionResult!
@@ -254,7 +254,7 @@ public enum OnionRequestAPI: OnionRequestAPIType {
         return getPath(excluding: snodeToExclude).then2 { path -> Promise<AESGCM.EncryptionResult> in
             guardSnode = path.first!
             // Encrypt in reverse order, i.e. the destination first
-            return encrypt(payload, for: destination).then2 { r -> Promise<AESGCM.EncryptionResult> in
+            return encrypt(payload, for: destination, with: version).then2 { r -> Promise<AESGCM.EncryptionResult> in
                 targetSnodeSymmetricKey = r.symmetricKey
                 // Recursively encrypt the layers of the onion (again in reverse order)
                 encryptionResult = r
@@ -328,7 +328,7 @@ public enum OnionRequestAPI: OnionRequestAPIType {
         let (promise, seal) = Promise<(OnionRequestResponseInfoType, Data?)>.pending()
         var guardSnode: Snode?
         Threading.workQueue.async { // Avoid race conditions on `guardSnodes` and `paths`
-            buildOnion(around: payload, targetedAt: destination).done2 { intermediate in
+            buildOnion(around: payload, targetedAt: destination, version: version).done2 { intermediate in
                 guardSnode = intermediate.guardSnode
                 let url = "\(guardSnode!.address):\(guardSnode!.port)/onion_req/v2"
                 let finalEncryptionResult = intermediate.finalEncryptionResult

SessionSnodeKit/SnodeAPI.swift

@@ -131,8 +131,15 @@ public final class SnodeAPI : NSObject {
     // MARK: Internal API
     internal static func invoke(_ method: Snode.Method, on snode: Snode, associatedWith publicKey: String? = nil, parameters: JSON) -> RawResponsePromise {
         if Features.useOnionRequests {
-            // TODO: Ensure this should use the v3 request?
+            return OnionRequestAPI.sendOnionRequest(to: snode, invoking: method, with: parameters, using: .v3, associatedWith: publicKey)
-            return OnionRequestAPI.sendOnionRequest(to: snode, invoking: method, with: parameters, using: .v3, associatedWith: publicKey).map2 { $0 as Any }
+                .map2 { responseData in
+                    guard let responseJson: JSON = try? JSONSerialization.jsonObject(with: responseData, options: [ .fragmentsAllowed ]) as? JSON else {
+                        throw Error.generic
+                    }
+                    
+                    // FIXME: Would be nice to change this to not send 'Any'
+                    return responseJson as Any
+                }
         } else {
             let url = "\(snode.address):\(snode.port)/storage_rpc/v1"
             return HTTP.execute(.post, url, parameters: parameters).map2 { $0 as Any }.recover2 { error -> Promise<Any> in