session-ios/SessionMessagingKit/Sending & Receiving/MessageReceiver+Handling.swift

1312 lines
56 KiB
Swift

// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.
import Foundation
import GRDB
import Sodium
import Curve25519Kit
import SignalCoreKit
import SessionSnodeKit
import SessionUtilitiesKit
extension MessageReceiver {
public static func handle(_ db: Database, message: Message, associatedWithProto proto: SNProtoContent, openGroupId: String?, isBackgroundPoll: Bool) throws {
switch message {
case let message as ReadReceipt: try handleReadReceipt(db, message: message)
case let message as TypingIndicator: try handleTypingIndicator(db, message: message)
case let message as ClosedGroupControlMessage: try handleClosedGroupControlMessage(db, message)
case let message as DataExtractionNotification:
try handleDataExtractionNotification(db, message: message)
case let message as ExpirationTimerUpdate: try handleExpirationTimerUpdate(db, message: message)
case let message as ConfigurationMessage: try handleConfigurationMessage(db, message)
case let message as UnsendRequest: try handleUnsendRequest(db, message: message)
case let message as MessageRequestResponse: try handleMessageRequestResponse(db, message)
case let message as VisibleMessage:
try handleVisibleMessage(db, message: message, associatedWithProto: proto, openGroupId: openGroupId, isBackgroundPoll: isBackgroundPoll)
default: fatalError()
}
// When handling any non-typing indicator message we want to make sure the thread becomes
// visible (the only other spot this flag gets set is when sending messages)
switch message {
case is TypingIndicator: break
default:
guard let threadInfo: (id: String, variant: SessionThread.Variant) = threadInfo(db, message: message, openGroupId: openGroupId) else {
return
}
_ = try SessionThread
.fetchOrCreate(db, id: threadInfo.id, variant: threadInfo.variant)
.with(shouldBeVisible: true)
.saved(db)
}
}
// MARK: - Convenience
private static func threadInfo(_ db: Database, message: Message, openGroupId: String?) -> (id: String, variant: SessionThread.Variant)? {
if let openGroupId: String = openGroupId {
// Note: We don't want to create a thread for an open group if it doesn't exist
if (try? SessionThread.exists(db, id: openGroupId)) != true { return nil }
return (openGroupId, .openGroup)
}
if let groupPublicKey: String = message.groupPublicKey {
// Note: We don't want to create a thread for a closed group if it doesn't exist
if (try? SessionThread.exists(db, id: groupPublicKey)) != true { return nil }
return (groupPublicKey, .closedGroup)
}
// Extract the 'syncTarget' value if there is one
let maybeSyncTarget: String?
switch message {
case let message as VisibleMessage: maybeSyncTarget = message.syncTarget
case let message as ExpirationTimerUpdate: maybeSyncTarget = message.syncTarget
default: maybeSyncTarget = nil
}
// Note: We don't want to create a thread for a closed group if it doesn't exist
guard let contactId: String = (maybeSyncTarget ?? message.sender) else { return nil }
return (contactId, .contact)
}
// MARK: - Read Receipts
private static func handleReadReceipt(_ db: Database, message: ReadReceipt) throws {
guard let sender: String = message.sender else { return }
guard let timestampMsValues: [Double] = message.timestamps?.map({ Double($0) }) else { return }
guard let readTimestampMs: Double = message.receivedTimestamp.map({ Double($0) }) else { return }
try Interaction.markAsRead(
db,
recipientId: sender,
timestampMsValues: timestampMsValues,
readTimestampMs: readTimestampMs
)
}
// MARK: - Typing Indicators
private static func handleTypingIndicator(_ db: Database, message: TypingIndicator) throws {
guard
let senderPublicKey: String = message.sender,
let thread: SessionThread = try SessionThread.fetchOne(db, id: senderPublicKey)
else { return }
switch message.kind {
case .started:
TypingIndicators.didStartTyping(
db,
threadId: thread.id,
threadVariant: thread.variant,
threadIsMessageRequest: thread.isMessageRequest(db),
direction: .incoming,
timestampMs: message.sentTimestamp.map { Int64($0) }
)
case .stopped:
TypingIndicators.didStopTyping(db, threadId: thread.id, direction: .incoming)
default:
SNLog("Unknown TypingIndicator Kind ignored")
return
}
}
// MARK: - Data Extraction Notification
private static func handleDataExtractionNotification(_ db: Database, message: DataExtractionNotification) throws {
guard
let sender: String = message.sender,
let messageKind: DataExtractionNotification.Kind = message.kind,
let thread: SessionThread = try? SessionThread.fetchOne(db, id: sender),
thread.variant == .contact
else { return }
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: sender,
variant: {
switch messageKind {
case .screenshot: return .infoScreenshotNotification
case .mediaSaved: return .infoMediaSavedNotification
}
}()
).inserted(db)
}
// MARK: - Expiration Timers
private static func handleExpirationTimerUpdate(_ db: Database, message: ExpirationTimerUpdate) throws {
// Get the target thread
guard
let targetId: String = threadInfo(db, message: message, openGroupId: nil)?.id,
let sender: String = message.sender,
let thread: SessionThread = try? SessionThread.fetchOne(db, id: targetId)
else { return }
// Update the configuration
//
// Note: Messages which had been sent during the previous configuration will still
// use it's settings (so if you enable, send a message and then disable disappearing
// message then the message you had sent will still disappear)
let config: DisappearingMessagesConfiguration = try thread.disappearingMessagesConfiguration
.fetchOne(db)
.defaulting(to: DisappearingMessagesConfiguration.defaultWith(thread.id))
.with(
// If there is no duration then we should disable the expiration timer
isEnabled: ((message.duration ?? 0) > 0),
durationSeconds: (
message.duration.map { TimeInterval($0) } ??
DisappearingMessagesConfiguration.defaultDuration
)
)
// Add an info message for the user
_ = try Interaction(
serverHash: nil, // Intentionally null so sync messages are seen as duplicates
threadId: thread.id,
authorId: sender,
variant: .infoDisappearingMessagesUpdate,
body: config.messageInfoString(
with: (sender != getUserHexEncodedPublicKey(db) ?
Profile.displayName(db, id: sender) :
nil
)
),
timestampMs: Int64(message.sentTimestamp ?? 0) // Default to `0` if not set
).inserted(db)
// Finally save the changes to the DisappearingMessagesConfiguration (If it's a duplicate
// then the interaction unique constraint will prevent the code from getting here)
try config.save(db)
}
// MARK: - Configuration Messages
private static func handleConfigurationMessage(_ db: Database, _ message: ConfigurationMessage) throws {
let userPublicKey = getUserHexEncodedPublicKey(db)
guard message.sender == userPublicKey else { return }
SNLog("Configuration message received.")
// Note: `message.sentTimestamp` is in ms (convert to TimeInterval before converting to
// seconds to maintain the accuracy)
let isInitialSync: Bool = (!UserDefaults.standard[.hasSyncedInitialConfiguration])
let messageSentTimestamp: TimeInterval = TimeInterval((message.sentTimestamp ?? 0) / 1000)
let lastConfigTimestamp: TimeInterval = UserDefaults.standard[.lastConfigurationSync]
.defaulting(to: Date(timeIntervalSince1970: 0))
.timeIntervalSince1970
// Profile
try updateProfileIfNeeded(
db,
publicKey: userPublicKey,
name: message.displayName,
profilePictureUrl: message.profilePictureUrl,
profileKey: OWSAES256Key(data: message.profileKey),
sentTimestamp: messageSentTimestamp
)
if isInitialSync || messageSentTimestamp > lastConfigTimestamp {
if isInitialSync {
UserDefaults.standard[.hasSyncedInitialConfiguration] = true
NotificationCenter.default.post(name: .initialConfigurationMessageReceived, object: nil)
}
UserDefaults.standard[.lastConfigurationSync] = Date(timeIntervalSince1970: messageSentTimestamp)
// Contacts
try message.contacts.forEach { contactInfo in
guard let sessionId: String = contactInfo.publicKey else { return }
let contact: Contact = Contact.fetchOrCreate(db, id: sessionId)
let profile: Profile = Profile.fetchOrCreate(db, id: sessionId)
try profile
.with(
name: contactInfo.displayName,
profilePictureUrl: .updateIf(contactInfo.profilePictureUrl),
profileEncryptionKey: .updateIf(
contactInfo.profileKey.map { OWSAES256Key(data: $0) }
)
)
.save(db)
/// We only update these values if the proto actually has values for them (this is to prevent an
/// edge case where an old client could override the values with default values since they aren't included)
///
/// **Note:** Since message requests have no reverse, we should only handle setting `isApproved`
/// and `didApproveMe` to `true`. This may prevent some weird edge cases where a config message
/// swapping `isApproved` and `didApproveMe` to `false`
try contact
.with(
isApproved: (contactInfo.hasIsApproved && contactInfo.isApproved ?
true :
.existing
),
isBlocked: (contactInfo.hasIsBlocked ?
.update(contactInfo.isBlocked) :
.existing
),
didApproveMe: (contactInfo.hasDidApproveMe && contactInfo.didApproveMe ?
true :
.existing
)
)
.save(db)
// If the contact is blocked
if contactInfo.hasIsBlocked && contactInfo.isBlocked {
// If this message changed them to the blocked state and there is an existing thread
// associated with them that is a message request thread then delete it (assume
// that the current user had deleted that message request)
if
contactInfo.isBlocked != contact.isBlocked,
let thread: SessionThread = try? SessionThread.fetchOne(db, id: sessionId),
thread.isMessageRequest(db)
{
_ = try thread.delete(db)
}
}
}
// Closed groups
//
// Note: Only want to add these for initial sync to avoid re-adding closed groups the user
// intentionally left (any closed groups joined since the first processed sync message should
// get added via the 'handleNewClosedGroup' method anyway as they will have come through in the
// past two weeks)
if isInitialSync {
let existingClosedGroupsIds: [String] = (try? SessionThread
.filter(SessionThread.Columns.variant == SessionThread.Variant.closedGroup)
.fetchAll(db))
.defaulting(to: [])
.map { $0.id }
try message.closedGroups.forEach { closedGroup in
guard !existingClosedGroupsIds.contains(closedGroup.publicKey) else { return }
let keyPair: Box.KeyPair = Box.KeyPair(
publicKey: closedGroup.encryptionKeyPublicKey.bytes,
secretKey: closedGroup.encryptionKeySecretKey.bytes
)
try handleNewClosedGroup(
db,
groupPublicKey: closedGroup.publicKey,
name: closedGroup.name,
encryptionKeyPair: keyPair,
members: [String](closedGroup.members),
admins: [String](closedGroup.admins),
expirationTimer: closedGroup.expirationTimer,
messageSentTimestamp: message.sentTimestamp!
)
}
}
// Open groups
for openGroupURL in message.openGroups {
if let (room, server, publicKey) = OpenGroupManagerV2.parseV2OpenGroup(from: openGroupURL) {
OpenGroupManagerV2.shared
.add(db, room: room, server: server, publicKey: publicKey)
.retainUntilComplete()
}
}
}
}
// MARK: - Unsend Requests
public static func handleUnsendRequest(_ db: Database, message: UnsendRequest) throws {
let userPublicKey: String = getUserHexEncodedPublicKey(db)
guard message.sender == message.author || userPublicKey == message.sender else { return }
guard let author: String = message.author, let timestampMs: UInt64 = message.timestamp else { return }
let maybeInteraction: Interaction? = try Interaction
.filter(Interaction.Columns.timestampMs == Int64(timestampMs))
.filter(Interaction.Columns.authorId == author)
.fetchOne(db)
guard
let interactionId: Int64 = maybeInteraction?.id,
let interaction: Interaction = maybeInteraction
else { return }
// Mark incoming messages as read and remove any of their notifications
if interaction.variant == .standardIncoming {
try Interaction.markAsRead(
db,
interactionId: interactionId,
threadId: interaction.threadId,
includingOlder: false,
trySendReadReceipt: false
)
UNUserNotificationCenter.current().removeDeliveredNotifications(withIdentifiers: interaction.notificationIdentifiers)
UNUserNotificationCenter.current().removePendingNotificationRequests(withIdentifiers: interaction.notificationIdentifiers)
}
if author == message.sender, let serverHash: String = interaction.serverHash {
SnodeAPI.deleteMessage(publicKey: author, serverHashes: [serverHash]).retainUntilComplete()
}
switch (interaction.variant, (author == message.sender)) {
case (.standardOutgoing, _), (_, false):
_ = try interaction.delete(db)
case (_, true):
_ = try interaction
.markingAsDeleted()
.saved(db)
_ = try interaction.attachments
.deleteAll(db)
}
}
// MARK: - Visible Messages
@discardableResult public static func handleVisibleMessage(
_ db: Database,
message: VisibleMessage,
associatedWithProto proto: SNProtoContent,
openGroupId: String?,
isBackgroundPoll: Bool
) throws -> Int64 {
guard let sender: String = message.sender, let dataMessage = proto.dataMessage else {
throw MessageReceiverError.invalidMessage
}
// Note: `message.sentTimestamp` is in ms (convert to TimeInterval before converting to
// seconds to maintain the accuracy)
let messageSentTimestamp: TimeInterval = (TimeInterval(message.sentTimestamp ?? 0) / 1000)
let isMainAppActive: Bool = (UserDefaults.sharedLokiProject?[.isMainAppActive]).defaulting(to: false)
// Update profile if needed (want to do this regardless of whether the message exists or
// not to ensure the profile info gets sync between a users devices at every chance)
if let profile = message.profile {
var contactProfileKey: OWSAES256Key? = nil
if let profileKey = profile.profileKey { contactProfileKey = OWSAES256Key(data: profileKey) }
try updateProfileIfNeeded(
db,
publicKey: sender,
name: profile.displayName,
profilePictureUrl: profile.profilePictureUrl,
profileKey: contactProfileKey,
sentTimestamp: messageSentTimestamp
)
}
// Get or create thread
guard let threadInfo: (id: String, variant: SessionThread.Variant) = threadInfo(db, message: message, openGroupId: openGroupId) else {
throw MessageReceiverError.noThread
}
// Store the message variant so we can run variant-specific behaviours
let currentUserPublicKey: String = getUserHexEncodedPublicKey(db)
let thread: SessionThread = try SessionThread
.fetchOrCreate(db, id: threadInfo.id, variant: threadInfo.variant)
let variant: Interaction.Variant = (sender == currentUserPublicKey ?
.standardOutgoing :
.standardIncoming
)
// Retrieve the disappearing messages config to set the 'expiresInSeconds' value
// accoring to the config
let disappearingMessagesConfiguration: DisappearingMessagesConfiguration = (try? thread.disappearingMessagesConfiguration.fetchOne(db))
.defaulting(to: DisappearingMessagesConfiguration.defaultWith(thread.id))
// Try to insert the interaction
//
// Note: There are now a number of unique constraints on the database which
// prevent the ability to insert duplicate interactions at a database level
// so we don't need to check for the existance of a message beforehand anymore
let interaction: Interaction
do {
interaction = try Interaction(
serverHash: message.serverHash, // Keep track of server hash
threadId: thread.id,
authorId: sender,
variant: variant,
body: message.text,
timestampMs: Int64(messageSentTimestamp * 1000),
wasRead: (variant == .standardOutgoing), // Auto-mark sent messages as read
hasMention: (
message.text?.contains("@\(currentUserPublicKey)") == true ||
dataMessage.quote?.author == currentUserPublicKey
),
// Note: Ensure we don't ever expire open group messages
expiresInSeconds: (disappearingMessagesConfiguration.isEnabled && message.openGroupServerMessageId == nil ?
disappearingMessagesConfiguration.durationSeconds :
nil
),
expiresStartedAtMs: nil,
// OpenGroupInvitations are stored as LinkPreview's in the database
linkPreviewUrl: (message.linkPreview?.url ?? message.openGroupInvitation?.url),
// Keep track of the open group server message ID message ID relationship
openGroupServerMessageId: message.openGroupServerMessageId.map { Int64($0) },
openGroupWhisperMods: false,
openGroupWhisperTo: nil
).inserted(db)
}
catch {
switch error {
case DatabaseError.SQLITE_CONSTRAINT_UNIQUE:
guard
variant == .standardOutgoing,
let existingInteractionId: Int64 = try? thread.interactions
.select(.id)
.filter(Interaction.Columns.timestampMs == (messageSentTimestamp * 1000))
.filter(Interaction.Columns.variant == variant)
.filter(Interaction.Columns.authorId == sender)
.asRequest(of: Int64.self)
.fetchOne(db)
else { break }
// If we receive an outgoing message that already exists in the database
// then we still need up update the recipient and read states for the
// message (even if we don't need to do anything else)
try updateRecipientAndReadStates(
db,
thread: thread,
interactionId: existingInteractionId,
variant: variant,
syncTarget: message.syncTarget
)
default: break
}
throw error
}
guard let interactionId: Int64 = interaction.id else { throw StorageError.failedToSave }
// Update and recipient and read states as needed
try updateRecipientAndReadStates(
db,
thread: thread,
interactionId: interactionId,
variant: variant,
syncTarget: message.syncTarget
)
// Parse & persist attachments
let attachments: [Attachment] = try dataMessage.attachments
.compactMap { proto -> Attachment? in
let attachment: Attachment = Attachment(proto: proto)
// Attachments on received messages must have a 'downloadUrl' otherwise
// they are invalid and we can ignore them
return (attachment.downloadUrl != nil ? attachment : nil)
}
.enumerated()
.map { index, attachment in
let savedAttachment: Attachment = try attachment.saved(db)
// Link the attachment to the interaction and add to the id lookup
try InteractionAttachment(
albumIndex: index,
interactionId: interactionId,
attachmentId: savedAttachment.id
).insert(db)
return savedAttachment
}
message.attachmentIds = attachments.map { $0.id }
// Persist quote if needed
let quote: Quote? = try? Quote(
db,
proto: dataMessage,
interactionId: interactionId,
thread: thread
)?.inserted(db)
// Parse link preview if needed
let linkPreview: LinkPreview? = try? LinkPreview(
db,
proto: dataMessage,
body: message.text,
sentTimestampMs: (messageSentTimestamp * 1000)
)?.saved(db)
// Open group invitations are stored as LinkPreview values so create one if needed
if
let openGroupInvitationUrl: String = message.openGroupInvitation?.url,
let openGroupInvitationName: String = message.openGroupInvitation?.name
{
try LinkPreview(
url: openGroupInvitationUrl,
timestamp: LinkPreview.timestampFor(sentTimestampMs: (messageSentTimestamp * 1000)),
variant: .openGroupInvitation,
title: openGroupInvitationName
).save(db)
}
// Start attachment downloads if needed (ie. trusted contact or group thread)
let isContactTrusted: Bool = ((try? Contact.fetchOne(db, id: sender))?.isTrusted ?? false)
if isContactTrusted || thread.variant != .contact {
attachments
.map { $0.id }
.appending(quote?.attachmentId)
.appending(linkPreview?.attachmentId)
.forEach { attachmentId in
JobRunner.add(
db,
job: Job(
variant: .attachmentDownload,
threadId: thread.id,
interactionId: interactionId,
details: AttachmentDownloadJob.Details(
attachmentId: attachmentId
)
),
canStartJob: isMainAppActive
)
}
}
// Cancel any typing indicators if needed
if isMainAppActive {
TypingIndicators.didStopTyping(db, threadId: thread.id, direction: .incoming)
}
// Update the contact's approval status of the current user if needed (if we are getting messages from
// them outside of a group then we can assume they have approved the current user)
//
// Note: This is to resolve a rare edge-case where a conversation was started with a user on an old
// version of the app and their message request approval state was set via a migration rather than
// by using the approval process
if thread.variant == .contact {
try updateContactApprovalStatusIfNeeded(
db,
senderSessionId: sender,
threadId: thread.id,
forceConfigSync: false
)
}
// Notify the user if needed
guard variant == .standardIncoming else { return interactionId }
// Use the same identifier for notifications when in backgroud polling to prevent spam
SSKEnvironment.shared.notificationsManager.wrappedValue?
.notifyUser(
db,
for: interaction,
in: thread,
isBackgroundPoll: isBackgroundPoll
)
return interactionId
}
private static func updateRecipientAndReadStates(
_ db: Database,
thread: SessionThread,
interactionId: Int64,
variant: Interaction.Variant,
syncTarget: String?
) throws {
guard variant == .standardOutgoing else { return }
if let syncTarget: String = syncTarget {
try RecipientState(
interactionId: interactionId,
recipientId: syncTarget,
state: .sent
).save(db)
}
else if thread.variant == .closedGroup {
try GroupMember
.filter(GroupMember.Columns.groupId == thread.id)
.fetchAll(db)
.forEach { member in
try RecipientState(
interactionId: interactionId,
recipientId: member.profileId,
state: .sent
).save(db)
}
}
// For outgoing messages mark all older interactions as read (the user should have seen
// them if they send a message - also avoids a situation where the user has "phantom"
// unread messages that they need to scroll back to before they become marked as read)
try Interaction.markAsRead(
db,
interactionId: interactionId,
threadId: thread.id,
includingOlder: true,
trySendReadReceipt: true
)
}
// MARK: - Profile Updating
private static func updateProfileIfNeeded(
_ db: Database,
publicKey: String,
name: String?,
profilePictureUrl: String?,
profileKey: OWSAES256Key?,
sentTimestamp: TimeInterval
) throws {
let isCurrentUser = (publicKey == getUserHexEncodedPublicKey(db))
var profile: Profile = Profile.fetchOrCreate(id: publicKey)
// Name
if let name = name, name != profile.name {
let shouldUpdate: Bool
if isCurrentUser {
shouldUpdate = given(UserDefaults.standard[.lastDisplayNameUpdate]) {
sentTimestamp > $0.timeIntervalSince1970
}
.defaulting(to: true)
}
else {
shouldUpdate = true
}
if shouldUpdate {
if isCurrentUser {
UserDefaults.standard[.lastDisplayNameUpdate] = Date(timeIntervalSince1970: sentTimestamp)
}
profile = profile.with(name: name)
}
}
// Profile picture & profile key
if
let profileKey: OWSAES256Key = profileKey,
let profilePictureUrl: String = profilePictureUrl,
profileKey.keyData.count == kAES256_KeyByteLength,
profileKey != profile.profileEncryptionKey
{
let shouldUpdate: Bool
if isCurrentUser {
shouldUpdate = given(UserDefaults.standard[.lastProfilePictureUpdate]) {
sentTimestamp > $0.timeIntervalSince1970
}
.defaulting(to: true)
}
else {
shouldUpdate = true
}
if shouldUpdate {
if isCurrentUser {
UserDefaults.standard[.lastProfilePictureUpdate] = Date(timeIntervalSince1970: sentTimestamp)
}
profile = profile.with(
profilePictureUrl: .update(profilePictureUrl),
profileEncryptionKey: .update(profileKey)
)
}
}
// Persist changes
try profile.save(db)
// Download the profile picture if needed
db.afterNextTransactionCommit { _ in
ProfileManager.downloadAvatar(for: profile)
}
}
// MARK: - Closed Groups
public static func handleClosedGroupControlMessage(_ db: Database, _ message: ClosedGroupControlMessage) throws {
switch message.kind! {
case .new: try handleNewClosedGroup(db, message: message)
case .encryptionKeyPair: try handleClosedGroupEncryptionKeyPair(db, message: message)
case .nameChange: try handleClosedGroupNameChanged(db, message: message)
case .membersAdded: try handleClosedGroupMembersAdded(db, message: message)
case .membersRemoved: try handleClosedGroupMembersRemoved(db, message: message)
case .memberLeft: try handleClosedGroupMemberLeft(db, message: message)
case .encryptionKeyPairRequest:
handleClosedGroupEncryptionKeyPairRequest(db, message: message) // Currently not used
}
}
private static func handleNewClosedGroup(_ db: Database, message: ClosedGroupControlMessage) throws {
guard case let .new(publicKeyAsData, name, encryptionKeyPair, membersAsData, adminsAsData, expirationTimer) = message.kind else {
return
}
guard let sentTimestamp: UInt64 = message.sentTimestamp else { return }
try handleNewClosedGroup(
db,
groupPublicKey: publicKeyAsData.toHexString(),
name: name,
encryptionKeyPair: encryptionKeyPair,
members: membersAsData.map { $0.toHexString() },
admins: adminsAsData.map { $0.toHexString() },
expirationTimer: expirationTimer,
messageSentTimestamp: sentTimestamp
)
}
private static func handleNewClosedGroup(
_ db: Database,
groupPublicKey: String,
name: String,
encryptionKeyPair: Box.KeyPair,
members: [String],
admins: [String],
expirationTimer: UInt32,
messageSentTimestamp: UInt64
) throws {
// With new closed groups we only want to create them if the admin creating the closed group is an
// approved contact (to prevent spam via closed groups getting around message requests if users are
// on old or modified clients)
var hasApprovedAdmin: Bool = false
for adminId in admins {
if let contact: Contact = try? Contact.fetchOne(db, id: adminId), contact.isApproved {
hasApprovedAdmin = true
break
}
}
guard hasApprovedAdmin else { return }
// Create the group
let groupAlreadyExisted: Bool = ((try? SessionThread.exists(db, id: groupPublicKey)) ?? false)
let thread: SessionThread = try SessionThread
.fetchOrCreate(db, id: groupPublicKey, variant: .closedGroup)
.with(shouldBeVisible: true)
.saved(db)
let closedGroup: ClosedGroup = try ClosedGroup(
threadId: groupPublicKey,
name: name,
formationTimestamp: (TimeInterval(messageSentTimestamp) / 1000)
).saved(db)
// Clear the zombie list if the group wasn't active (ie. had no keys)
if ((try? closedGroup.keyPairs.fetchCount(db)) ?? 0) == 0 {
try closedGroup.zombies.deleteAll(db)
}
// Notify the user
if !groupAlreadyExisted {
// Create the GroupMember records
try members.forEach { memberId in
try GroupMember(
groupId: groupPublicKey,
profileId: memberId,
role: .standard
).save(db)
}
try admins.forEach { adminId in
try GroupMember(
groupId: groupPublicKey,
profileId: adminId,
role: .admin
).save(db)
}
// Note: We don't provide a `serverHash` in this case as we want to allow duplicates
// to avoid the following situation:
// The app performed a background poll or received a push notification
// This method was invoked and the received message timestamps table was updated
// Processing wasn't finished
// The user doesn't see the new closed group
_ = try Interaction(
threadId: thread.id,
authorId: getUserHexEncodedPublicKey(db),
variant: .infoClosedGroupCreated,
timestampMs: Int64(messageSentTimestamp)
).inserted(db)
}
// Update the DisappearingMessages config
try thread.disappearingMessagesConfiguration
.fetchOne(db)
.defaulting(to: DisappearingMessagesConfiguration.defaultWith(thread.id))
.with(
isEnabled: (expirationTimer > 0),
durationSeconds: TimeInterval(expirationTimer > 0 ?
expirationTimer :
(24 * 60 * 60)
)
)
.save(db)
// Store the key pair
try ClosedGroupKeyPair(
threadId: groupPublicKey,
publicKey: Data(encryptionKeyPair.publicKey),
secretKey: Data(encryptionKeyPair.secretKey),
receivedTimestamp: Date().timeIntervalSince1970
).insert(db)
// Start polling
ClosedGroupPoller.shared.startPolling(for: groupPublicKey)
// Notify the PN server
let _ = PushNotificationAPI.performOperation(.subscribe, for: groupPublicKey, publicKey: getUserHexEncodedPublicKey())
}
/// Extracts and adds the new encryption key pair to our list of key pairs if there is one for our public key, AND the message was
/// sent by the group admin.
private static func handleClosedGroupEncryptionKeyPair(_ db: Database, message: ClosedGroupControlMessage) throws {
guard
case let .encryptionKeyPair(explicitGroupPublicKey, wrappers) = message.kind,
let groupPublicKey: String = (explicitGroupPublicKey?.toHexString() ?? message.groupPublicKey)
else { return }
guard let userKeyPair: Box.KeyPair = Identity.fetchUserKeyPair(db) else {
return SNLog("Couldn't find user X25519 key pair.")
}
guard let thread: SessionThread = try? SessionThread.fetchOne(db, id: groupPublicKey) else {
return SNLog("Ignoring closed group encryption key pair for nonexistent group.")
}
guard let closedGroup: ClosedGroup = try? thread.closedGroup.fetchOne(db) else { return }
guard let groupAdmins: [GroupMember] = try? closedGroup.admins.fetchAll(db) else { return }
guard let sender: String = message.sender, groupAdmins.contains(where: { $0.profileId == sender }) else {
return SNLog("Ignoring closed group encryption key pair from non-admin.")
}
// Find our wrapper and decrypt it if possible
let userPublicKey: String = userKeyPair.publicKey.toHexString()
guard
let wrapper = wrappers.first(where: { $0.publicKey == userPublicKey }),
let encryptedKeyPair = wrapper.encryptedKeyPair
else { return }
let plaintext: Data
do {
plaintext = try MessageReceiver.decryptWithSessionProtocol(
ciphertext: encryptedKeyPair,
using: userKeyPair
).plaintext
}
catch {
return SNLog("Couldn't decrypt closed group encryption key pair.")
}
// Parse it
let proto: SNProtoKeyPair
do {
proto = try SNProtoKeyPair.parseData(plaintext)
}
catch {
return SNLog("Couldn't parse closed group encryption key pair.")
}
do {
try ClosedGroupKeyPair(
threadId: groupPublicKey,
publicKey: proto.publicKey.removing05PrefixIfNeeded(),
secretKey: proto.privateKey,
receivedTimestamp: Date().timeIntervalSince1970
).insert(db)
}
catch {
return SNLog("Ignoring duplicate closed group encryption key pair.")
}
SNLog("Received a new closed group encryption key pair.")
}
private static func handleClosedGroupNameChanged(_ db: Database, message: ClosedGroupControlMessage) throws {
guard case let .nameChange(name) = message.kind else { return }
try performIfValid(db, message: message) { id, sender, thread, closedGroup in
try closedGroup
.with(name: name)
.save(db)
// Notify the user if needed
guard name != closedGroup.name else { return }
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: sender,
variant: .infoClosedGroupUpdated,
body: ClosedGroupControlMessage.Kind
.nameChange(name: name)
.infoMessage(db, sender: sender),
timestampMs: (
message.sentTimestamp.map { Int64($0) } ??
Int64(floor(Date().timeIntervalSince1970 * 1000))
)
).inserted(db)
}
}
private static func handleClosedGroupMembersAdded(_ db: Database, message: ClosedGroupControlMessage) throws {
guard case let .membersAdded(membersAsData) = message.kind else { return }
try performIfValid(db, message: message) { id, sender, thread, closedGroup in
guard let groupMembers: [GroupMember] = try? closedGroup.members.fetchAll(db) else { return }
guard let groupAdmins: [GroupMember] = try? closedGroup.admins.fetchAll(db) else { return }
// Update the group
let addedMembers: [String] = membersAsData.map { $0.toHexString() }
let currentMemberIds: Set<String> = groupMembers.map { $0.profileId }.asSet()
let members: Set<String> = currentMemberIds.union(addedMembers)
// Create records for any new members
try addedMembers
.filter { !currentMemberIds.contains($0) }
.forEach { memberId in
try GroupMember(
groupId: id,
profileId: memberId,
role: .standard
).insert(db)
}
// Send the latest encryption key pair to the added members if the current user is
// the admin of the group
//
// This fixes a race condition where:
// A member removes another member.
// A member adds someone to the group and sends them the latest group key pair.
// The admin is offline during all of this.
// When the admin comes back online they see the member removed message and generate +
// distribute a new key pair, but they don't know about the added member yet.
// Now they see the member added message.
//
// Without the code below, the added member(s) would never get the key pair that was
// generated by the admin when they saw the member removed message.
let userPublicKey: String = getUserHexEncodedPublicKey(db)
if groupAdmins.contains(where: { $0.profileId == userPublicKey }) {
addedMembers.forEach { memberId in
MessageSender.sendLatestEncryptionKeyPair(db, to: memberId, for: id)
}
}
// Remove any 'zombie' versions of the added members (in case they were re-added)
_ = try closedGroup
.zombies
.filter(addedMembers.contains(GroupMember.Columns.profileId))
.deleteAll(db)
// Notify the user if needed
guard members != Set(groupMembers.map { $0.profileId }) else { return }
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: sender,
variant: .infoClosedGroupUpdated,
body: ClosedGroupControlMessage.Kind
.membersAdded(
members: addedMembers
.asSet()
.subtracting(groupMembers.map { $0.profileId })
.map { Data(hex: $0) }
)
.infoMessage(db, sender: sender),
timestampMs: (
message.sentTimestamp.map { Int64($0) } ??
Int64(floor(Date().timeIntervalSince1970 * 1000))
)
).inserted(db)
}
}
/// Removes the given members from the group IF
/// it wasn't the admin that was removed (that should happen through a `MEMBER_LEFT` message).
/// the admin sent the message (only the admin can truly remove members).
/// If we're among the users that were removed, delete all encryption key pairs and the group public key, unsubscribe
/// from push notifications for this closed group, and remove the given members from the zombie list for this group.
private static func handleClosedGroupMembersRemoved(_ db: Database, message: ClosedGroupControlMessage) throws {
guard case let .membersRemoved(membersAsData) = message.kind else { return }
try performIfValid(db, message: message) { id, sender, thread, closedGroup in
// Check that the admin wasn't removed
guard let groupMembers: [GroupMember] = try? closedGroup.members.fetchAll(db) else { return }
guard let groupAdmins: [GroupMember] = try? closedGroup.admins.fetchAll(db) else { return }
let removedMembers = membersAsData.map { $0.toHexString() }
let members = Set(groupMembers.map { $0.profileId }).subtracting(removedMembers)
guard let firstAdminId: String = groupAdmins.first?.profileId, members.contains(firstAdminId) else {
return SNLog("Ignoring invalid closed group update.")
}
// Check that the message was sent by the group admin
guard groupAdmins.contains(where: { $0.profileId == sender }) else {
return SNLog("Ignoring invalid closed group update.")
}
// If the current user was removed:
// Stop polling for the group
// Remove the key pairs associated with the group
// Notify the PN server
let userPublicKey: String = getUserHexEncodedPublicKey(db)
let wasCurrentUserRemoved: Bool = !members.contains(userPublicKey)
if wasCurrentUserRemoved {
ClosedGroupPoller.shared.stopPolling(for: id)
try closedGroup
.allMembers
.deleteAll(db)
_ = try closedGroup
.keyPairs
.deleteAll(db)
let _ = PushNotificationAPI.performOperation(
.unsubscribe,
for: id,
publicKey: userPublicKey
)
}
else {
// Remove the member from the group and it's zombies
try closedGroup.members
.filter(removedMembers.contains(GroupMember.Columns.profileId))
.deleteAll(db)
try closedGroup.zombies
.filter(removedMembers.contains(GroupMember.Columns.profileId))
.deleteAll(db)
}
// Notify the user if needed
guard members != Set(groupMembers.map { $0.profileId }) else { return }
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: sender,
variant: (wasCurrentUserRemoved ? .infoClosedGroupCurrentUserLeft : .infoClosedGroupUpdated),
body: ClosedGroupControlMessage.Kind
.membersRemoved(
members: removedMembers
.asSet()
.subtracting(groupMembers.map { $0.profileId })
.map { Data(hex: $0) }
)
.infoMessage(db, sender: sender),
timestampMs: (
message.sentTimestamp.map { Int64($0) } ??
Int64(floor(Date().timeIntervalSince1970 * 1000))
)
).inserted(db)
}
}
/// If a regular member left:
/// Mark them as a zombie (to be removed by the admin later).
/// If the admin left:
/// Unsubscribe from PNs, delete the group public key, etc. as the group will be disbanded.
private static func handleClosedGroupMemberLeft(_ db: Database, message: ClosedGroupControlMessage) throws {
guard case .memberLeft = message.kind else { return }
try performIfValid(db, message: message) { id, sender, thread, closedGroup in
guard let allGroupMembers: [GroupMember] = try? closedGroup.allMembers.fetchAll(db) else {
return
}
let userPublicKey: String = getUserHexEncodedPublicKey(db)
let didAdminLeave: Bool = allGroupMembers.contains(where: { member in
member.role == .admin && member.profileId == sender
})
let members: [GroupMember] = allGroupMembers.filter { $0.role == .standard }
let membersToRemove: [GroupMember] = members
.filter { member in
didAdminLeave || // If the admin leaves the group is disbanded
member.profileId == sender
}
let updatedMemberIds: Set<String> = members
.map { $0.profileId }
.asSet()
.subtracting(membersToRemove.map { $0.profileId })
if didAdminLeave || sender == userPublicKey {
// Remove the group from the database and unsubscribe from PNs
ClosedGroupPoller.shared.stopPolling(for: id)
try closedGroup
.allMembers
.deleteAll(db)
_ = try closedGroup
.keyPairs
.deleteAll(db)
let _ = PushNotificationAPI.performOperation(
.unsubscribe,
for: id,
publicKey: userPublicKey
)
}
else {
// Delete all old user roles and re-add them as a zombie
try closedGroup
.allMembers
.filter(GroupMember.Columns.profileId == sender)
.deleteAll(db)
try GroupMember(
groupId: id,
profileId: sender,
role: .zombie
).insert(db)
}
// Notify the user if needed
guard updatedMemberIds != Set(members.map { $0.profileId }) else { return }
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: sender,
variant: .infoClosedGroupUpdated,
body: ClosedGroupControlMessage.Kind
.memberLeft
.infoMessage(db, sender: sender),
timestampMs: (
message.sentTimestamp.map { Int64($0) } ??
Int64(floor(Date().timeIntervalSince1970 * 1000))
)
).inserted(db)
}
}
private static func handleClosedGroupEncryptionKeyPairRequest(_ db: Database, message: ClosedGroupControlMessage) {
/*
guard case .encryptionKeyPairRequest = message.kind else { return }
let transaction = transaction as! YapDatabaseReadWriteTransaction
guard let groupPublicKey = message.groupPublicKey else { return }
performIfValid(for: message, using: transaction) { groupID, _, group in
let publicKey = message.sender!
// Guard against self-sends
guard publicKey != getUserHexEncodedPublicKey() else {
return SNLog("Ignoring invalid closed group update.")
}
MessageSender.sendLatestEncryptionKeyPair(to: publicKey, for: groupPublicKey, using: transaction)
}
*/
}
private static func performIfValid(
_ db: Database,
message: ClosedGroupControlMessage,
_ update: (String, String, SessionThread, ClosedGroup
) throws -> Void) throws {
guard let groupPublicKey: String = message.groupPublicKey else { return }
guard let thread: SessionThread = try? SessionThread.fetchOne(db, id: groupPublicKey) else {
return SNLog("Ignoring closed group update for nonexistent group.")
}
guard let closedGroup: ClosedGroup = try? thread.closedGroup.fetchOne(db) else { return }
// Check that the message isn't from before the group was created
guard Double(message.sentTimestamp ?? 0) > closedGroup.formationTimestamp else {
return SNLog("Ignoring closed group update from before thread was created.")
}
guard let sender: String = message.sender else { return }
guard let members: [GroupMember] = try? closedGroup.members.fetchAll(db) else { return }
// Check that the sender is a member of the group
guard members.contains(where: { $0.profileId == sender }) else {
return SNLog("Ignoring closed group update from non-member.")
}
try update(groupPublicKey, sender, thread, closedGroup)
}
// MARK: - Message Requests
private static func updateContactApprovalStatusIfNeeded(
_ db: Database,
senderSessionId: String,
threadId: String?,
forceConfigSync: Bool
) throws {
let userPublicKey: String = getUserHexEncodedPublicKey(db)
// If the sender of the message was the current user
if senderSessionId == userPublicKey {
// Retrieve the contact for the thread the message was sent to (excluding 'NoteToSelf'
// threads) and if the contact isn't flagged as approved then do so
guard
let threadId: String = threadId,
let thread: SessionThread = try? SessionThread.fetchOne(db, id: threadId),
!thread.isNoteToSelf(db),
let contact: Contact = try? thread.contact.fetchOne(db),
!contact.isApproved
else { return }
try? contact
.with(isApproved: true)
.update(db)
}
else {
// The message was sent to the current user so flag their 'didApproveMe' as true (can't send a message to
// someone without approving them)
guard
let contact: Contact = try? Contact.fetchOne(db, id: senderSessionId),
!contact.didApproveMe
else { return }
try? contact
.with(didApproveMe: true)
.update(db)
}
// Force a config sync to ensure all devices know the contact approval state if desired
guard forceConfigSync else { return }
try MessageSender.syncConfiguration(db, forceSyncNow: true).retainUntilComplete()
}
private static func handleMessageRequestResponse(_ db: Database, _ message: MessageRequestResponse) throws {
let userPublicKey = getUserHexEncodedPublicKey(db)
// Ignore messages which were sent from the current user
guard message.sender != userPublicKey else { return }
guard let senderId: String = message.sender else { return }
// Get the existing thead and notify the user
if let thread: SessionThread = try? SessionThread.fetchOne(db, id: senderId) {
_ = try Interaction(
serverHash: message.serverHash,
threadId: thread.id,
authorId: senderId,
variant: .infoMessageRequestAccepted,
timestampMs: (
message.sentTimestamp.map { Int64($0) } ??
Int64(floor(Date().timeIntervalSince1970 * 1000))
)
).inserted(db)
}
try updateContactApprovalStatusIfNeeded(
db,
senderSessionId: senderId,
threadId: nil,
forceConfigSync: true
)
}
}