TM-SGNL-iOS/SignalServiceKit/Groups/GroupV2Params.swift
TeleMessage developers dde0620daf initial commit
2025-05-03 12:28:28 -07:00

296 lines
11 KiB
Swift

//
// Copyright 2020 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//
import Foundation
public import LibSignalClient
public struct GroupV2Params {
public let groupSecretParams: GroupSecretParams
public let groupSecretParamsData: Data
public let groupPublicParams: GroupPublicParams
public let groupPublicParamsData: Data
public init(groupSecretParams: GroupSecretParams) throws {
self.groupSecretParams = groupSecretParams
self.groupSecretParamsData = groupSecretParams.serialize().asData
let groupPublicParams = try groupSecretParams.getPublicParams()
self.groupPublicParams = groupPublicParams
self.groupPublicParamsData = groupPublicParams.serialize().asData
}
}
// MARK: -
public extension TSGroupModelV2 {
func groupV2Params() throws -> GroupV2Params {
return try GroupV2Params(groupSecretParams: try GroupSecretParams(contents: [UInt8](secretParamsData)))
}
}
// MARK: -
public extension GroupV2Params {
fileprivate func encryptString(_ value: String) throws -> Data {
guard let plaintext: Data = value.data(using: .utf8) else {
throw OWSAssertionError("Could not encrypt value.")
}
return try encryptBlob(plaintext)
}
fileprivate func decryptString(_ data: Data) throws -> String {
let plaintext = try decryptBlob(data)
guard let string = String(bytes: plaintext, encoding: .utf8) else {
throw OWSAssertionError("Could not decrypt value.")
}
return string
}
fileprivate func encryptBlob(_ plaintext: Data) throws -> Data {
let clientZkGroupCipher = ClientZkGroupCipher(groupSecretParams: groupSecretParams)
let ciphertext = try clientZkGroupCipher.encryptBlob(plaintext: [UInt8](plaintext)).asData
assert(ciphertext != plaintext)
assert(!ciphertext.isEmpty)
if plaintext.count <= Self.decryptedBlobCacheMaxItemSize {
let cacheKey = (ciphertext + groupSecretParamsData)
Self.decryptedBlobCache.setObject(plaintext, forKey: cacheKey)
}
return ciphertext
}
private static let decryptedBlobCache = LRUCache<Data, Data>(maxSize: 16,
shouldEvacuateInBackground: true)
private static let decryptedBlobCacheMaxItemSize: UInt = 4 * 1024
fileprivate func decryptBlob(_ ciphertext: Data) throws -> Data {
let cacheKey = (ciphertext + groupSecretParamsData)
if let plaintext = Self.decryptedBlobCache.object(forKey: cacheKey) {
return plaintext
}
let clientZkGroupCipher = ClientZkGroupCipher(groupSecretParams: groupSecretParams)
let plaintext = try clientZkGroupCipher.decryptBlob(blobCiphertext: [UInt8](ciphertext)).asData
assert(ciphertext != plaintext)
if plaintext.count <= Self.decryptedBlobCacheMaxItemSize {
Self.decryptedBlobCache.setObject(plaintext, forKey: cacheKey)
}
return plaintext
}
func aci(for userId: Data) throws -> Aci {
guard let aci = try serviceId(for: userId) as? Aci else {
throw ServiceIdError.wrongServiceIdKind
}
return aci
}
func serviceId(for userId: Data) throws -> ServiceId {
let uuidCiphertext = try UuidCiphertext(contents: [UInt8](userId))
return try serviceId(for: uuidCiphertext)
}
func aci(for uuidCiphertext: UuidCiphertext) throws -> Aci {
guard let aci = try serviceId(for: uuidCiphertext) as? Aci else {
throw ServiceIdError.wrongServiceIdKind
}
return aci
}
private static var maxGroupSize: Int {
return Int(RemoteConfig.current.groupsV2MaxGroupSizeHardLimit)
}
private static let decryptedServiceIdCache = LRUCache<Data, ServiceId>(
maxSize: Self.maxGroupSize,
nseMaxSize: Self.maxGroupSize
)
func serviceId(for uuidCiphertext: UuidCiphertext) throws -> ServiceId {
let cacheKey = (uuidCiphertext.serialize().asData + groupSecretParamsData)
if let plaintext = Self.decryptedServiceIdCache.object(forKey: cacheKey) {
return plaintext
}
let clientZkGroupCipher = ClientZkGroupCipher(groupSecretParams: self.groupSecretParams)
let serviceId = try clientZkGroupCipher.decrypt(uuidCiphertext)
Self.decryptedServiceIdCache.setObject(serviceId, forKey: cacheKey)
return serviceId
}
func userId(for serviceId: ServiceId) throws -> Data {
let clientZkGroupCipher = ClientZkGroupCipher(groupSecretParams: self.groupSecretParams)
let uuidCiphertext = try clientZkGroupCipher.encrypt(serviceId)
let userId = uuidCiphertext.serialize().asData
let cacheKey = (userId + groupSecretParamsData)
Self.decryptedServiceIdCache.setObject(serviceId, forKey: cacheKey)
return userId
}
private static let decryptedProfileKeyCache = LRUCache<Data, Data>(maxSize: Self.maxGroupSize,
nseMaxSize: Self.maxGroupSize)
func profileKey(forProfileKeyCiphertext profileKeyCiphertext: ProfileKeyCiphertext, aci: Aci) throws -> Data {
let cacheKey = (profileKeyCiphertext.serialize().asData + aci.serviceIdBinary + groupSecretParamsData)
if let plaintext = Self.decryptedProfileKeyCache.object(forKey: cacheKey) {
return plaintext
}
let clientZkGroupCipher = ClientZkGroupCipher(groupSecretParams: self.groupSecretParams)
let profileKey = try clientZkGroupCipher.decryptProfileKey(profileKeyCiphertext: profileKeyCiphertext, userId: aci)
let plaintext = profileKey.serialize().asData
Self.decryptedProfileKeyCache.setObject(plaintext, forKey: cacheKey)
return plaintext
}
}
// MARK: -
public extension GroupV2Params {
func decryptDisappearingMessagesTimer(_ ciphertext: Data?) -> DisappearingMessageToken {
guard let ciphertext = ciphertext else {
// Treat a missing value as disabled.
return DisappearingMessageToken.disabledToken
}
do {
let blobProtoData = try decryptBlob(ciphertext)
let blobProto = try GroupsProtoGroupAttributeBlob(serializedData: blobProtoData)
if let blobContent = blobProto.content {
switch blobContent {
case .disappearingMessagesDuration(let value):
return .token(forProtoExpireTimerSeconds: value)
default:
owsFailDebug("Invalid disappearing messages value.")
}
}
} catch {
owsFailDebug("Could not decrypt and parse disappearing messages state: \(error).")
}
return DisappearingMessageToken.disabledToken
}
func encryptDisappearingMessagesTimer(_ token: DisappearingMessageToken) throws -> Data {
do {
let duration = (token.isEnabled
? token.durationSeconds
: 0)
var blobBuilder = GroupsProtoGroupAttributeBlob.builder()
blobBuilder.setContent(GroupsProtoGroupAttributeBlobOneOfContent.disappearingMessagesDuration(duration))
let blobData = try blobBuilder.buildSerializedData()
let encryptedTimerData = try encryptBlob(blobData)
return encryptedTimerData
} catch {
owsFailDebug("Error: \(error)")
throw error
}
}
func decryptGroupName(_ ciphertext: Data?) -> String? {
guard let ciphertext = ciphertext else {
// Treat a missing value as no value.
return nil
}
do {
let blobProtoData = try decryptBlob(ciphertext)
let blobProto = try GroupsProtoGroupAttributeBlob(serializedData: blobProtoData)
if let blobContent = blobProto.content {
switch blobContent {
case .title(let value):
return value
default:
owsFailDebug("Invalid group name value.")
}
}
} catch {
owsFailDebug("Could not decrypt group name: \(error).")
}
return nil
}
func encryptGroupName(_ value: String) throws -> Data {
do {
var blobBuilder = GroupsProtoGroupAttributeBlob.builder()
blobBuilder.setContent(GroupsProtoGroupAttributeBlobOneOfContent.title(value))
let blobData = try blobBuilder.buildSerializedData()
let encryptedTimerData = try encryptBlob(blobData)
return encryptedTimerData
} catch {
owsFailDebug("Error: \(error)")
throw error
}
}
func decryptGroupDescription(_ ciphertext: Data?) -> String? {
guard let ciphertext = ciphertext else {
// Treat a missing value as no value.
return nil
}
do {
let blobProtoData = try decryptBlob(ciphertext)
let blobProto = try GroupsProtoGroupAttributeBlob(serializedData: blobProtoData)
if let blobContent = blobProto.content {
switch blobContent {
case .descriptionText(let value):
return value
default:
owsFailDebug("Invalid group description value.")
}
}
} catch {
owsFailDebug("Could not decrypt group name: \(error).")
}
return nil
}
func encryptGroupDescription(_ value: String) throws -> Data {
do {
var blobBuilder = GroupsProtoGroupAttributeBlob.builder()
blobBuilder.setContent(GroupsProtoGroupAttributeBlobOneOfContent.descriptionText(value))
let blobData = try blobBuilder.buildSerializedData()
let ciphertext = try encryptBlob(blobData)
return ciphertext
} catch {
owsFailDebug("Error: \(error)")
throw error
}
}
func decryptGroupAvatar(_ ciphertext: Data) throws -> Data? {
do {
let blobProtoData = try decryptBlob(ciphertext)
let blobProto = try GroupsProtoGroupAttributeBlob(serializedData: blobProtoData)
if let blobContent = blobProto.content {
switch blobContent {
case .avatar(let value):
return value
default:
owsFailDebug("Invalid group avatar value.")
}
}
return nil
} catch {
owsFailDebug("Error: \(error)")
throw error
}
}
func encryptGroupAvatar(_ value: Data) throws -> Data {
do {
var blobBuilder = GroupsProtoGroupAttributeBlob.builder()
blobBuilder.setContent(GroupsProtoGroupAttributeBlobOneOfContent.avatar(value))
let blobData = try blobBuilder.buildSerializedData()
return try encryptBlob(blobData)
} catch {
owsFailDebug("Error: \(error)")
throw error
}
}
}