Implement password-protected rooms with encryption

- Room creators can set/remove passwords for their rooms
- Passwords are used to derive encryption keys via PBKDF2
- All messages in password-protected rooms are encrypted with AES-GCM
- Room protection status is announced to all peers
- Password and room data persists across app launches
- Visual lock indicators for password-protected rooms
- Password prompts when joining protected rooms
- Only room creators can modify password settings
- Encrypted messages show placeholder text if password is unknown
This commit is contained in:
jack
2025-07-05 19:35:37 +02:00
parent 4dec23e216
commit 8d553adc0c
5 changed files with 434 additions and 26 deletions
+28 -6
View File
@@ -180,14 +180,14 @@ extension BitchatMessage {
var data = Data()
// Message format:
// - Flags: 1 byte (bit 0: isRelay, bit 1: isPrivate, bit 2: hasOriginalSender, bit 3: hasRecipientNickname, bit 4: hasSenderPeerID, bit 5: hasMentions, bit 6: hasVoiceNote)
// - Flags: 1 byte (bit 0: isRelay, bit 1: isPrivate, bit 2: hasOriginalSender, bit 3: hasRecipientNickname, bit 4: hasSenderPeerID, bit 5: hasMentions, bit 6: hasRoom, bit 7: isEncrypted)
// - Timestamp: 8 bytes (seconds since epoch)
// - ID length: 1 byte
// - ID: variable
// - Sender length: 1 byte
// - Sender: variable
// - Content length: 2 bytes
// - Content: variable
// - Content: variable (or encrypted content if isEncrypted)
// Optional fields based on flags:
// - Original sender length + data
// - Recipient nickname length + data
@@ -203,6 +203,7 @@ extension BitchatMessage {
if senderPeerID != nil { flags |= 0x10 }
if mentions != nil && !mentions!.isEmpty { flags |= 0x20 }
if room != nil { flags |= 0x40 }
if isEncrypted { flags |= 0x80 }
data.append(flags)
@@ -229,8 +230,14 @@ extension BitchatMessage {
data.append(0)
}
// Content
if let contentData = content.data(using: .utf8) {
// Content or encrypted content
if isEncrypted, let encryptedContent = encryptedContent {
let length = UInt16(min(encryptedContent.count, 65535))
// Encode length as 2 bytes, big-endian
data.append(UInt8((length >> 8) & 0xFF))
data.append(UInt8(length & 0xFF))
data.append(encryptedContent.prefix(Int(length)))
} else if let contentData = content.data(using: .utf8) {
let length = UInt16(min(contentData.count, 65535))
// Encode length as 2 bytes, big-endian
data.append(UInt8((length >> 8) & 0xFF))
@@ -301,6 +308,7 @@ extension BitchatMessage {
let hasSenderPeerID = (flags & 0x10) != 0
let hasMentions = (flags & 0x20) != 0
let hasRoom = (flags & 0x40) != 0
let isEncrypted = (flags & 0x80) != 0
// Timestamp
guard offset + 8 <= dataCopy.count else {
@@ -347,7 +355,19 @@ extension BitchatMessage {
guard offset + contentLength <= dataCopy.count else {
return nil
}
let content = String(data: dataCopy[offset..<offset+contentLength], encoding: .utf8) ?? ""
let content: String
let encryptedContent: Data?
if isEncrypted {
// Content is encrypted, store as Data
encryptedContent = dataCopy[offset..<offset+contentLength]
content = "" // Empty placeholder
} else {
// Normal string content
content = String(data: dataCopy[offset..<offset+contentLength], encoding: .utf8) ?? ""
encryptedContent = nil
}
offset += contentLength
// Optional fields
@@ -418,7 +438,9 @@ extension BitchatMessage {
recipientNickname: recipientNickname,
senderPeerID: senderPeerID,
mentions: mentions,
room: room
room: room,
encryptedContent: encryptedContent,
isEncrypted: isEncrypted
)
return message
}
+17 -1
View File
@@ -69,6 +69,7 @@ enum MessageType: UInt8 {
case fragmentStart = 0x05
case fragmentContinue = 0x06
case fragmentEnd = 0x07
case roomAnnounce = 0x08 // Announce password-protected room status
}
// Special recipient ID for broadcast messages
@@ -134,8 +135,10 @@ struct BitchatMessage: Codable, Equatable {
let senderPeerID: String?
let mentions: [String]? // Array of mentioned nicknames
let room: String? // Room hashtag (e.g., "#general")
let encryptedContent: Data? // For password-protected rooms
let isEncrypted: Bool // Flag to indicate if content is encrypted
init(sender: String, content: String, timestamp: Date, isRelay: Bool, originalSender: String? = nil, isPrivate: Bool = false, recipientNickname: String? = nil, senderPeerID: String? = nil, mentions: [String]? = nil, room: String? = nil) {
init(sender: String, content: String, timestamp: Date, isRelay: Bool, originalSender: String? = nil, isPrivate: Bool = false, recipientNickname: String? = nil, senderPeerID: String? = nil, mentions: [String]? = nil, room: String? = nil, encryptedContent: Data? = nil, isEncrypted: Bool = false) {
self.id = UUID().uuidString
self.sender = sender
self.content = content
@@ -147,6 +150,8 @@ struct BitchatMessage: Codable, Equatable {
self.senderPeerID = senderPeerID
self.mentions = mentions
self.room = room
self.encryptedContent = encryptedContent
self.isEncrypted = isEncrypted
}
}
@@ -156,6 +161,8 @@ protocol BitchatDelegate: AnyObject {
func didDisconnectFromPeer(_ peerID: String)
func didUpdatePeerList(_ peers: [String])
func didReceiveRoomLeave(_ room: String, from peerID: String)
func didReceivePasswordProtectedRoomAnnouncement(_ room: String, isProtected: Bool, creatorID: String?)
func decryptRoomMessage(_ encryptedContent: Data, room: String) -> String?
// Optional method to check if a fingerprint belongs to a favorite peer
func isFavorite(fingerprint: String) -> Bool
@@ -170,4 +177,13 @@ extension BitchatDelegate {
func didReceiveRoomLeave(_ room: String, from peerID: String) {
// Default empty implementation
}
func didReceivePasswordProtectedRoomAnnouncement(_ room: String, isProtected: Bool, creatorID: String?) {
// Default empty implementation
}
func decryptRoomMessage(_ encryptedContent: Data, room: String) -> String? {
// Default returns nil (unable to decrypt)
return nil
}
}
+122 -2
View File
@@ -685,6 +685,88 @@ class BluetoothMeshService: NSObject {
}
}
func announcePasswordProtectedRoom(_ room: String, isProtected: Bool = true, creatorID: String? = nil) {
messageQueue.async { [weak self] in
guard let self = self else { return }
// Payload format: room|isProtected|creatorID
let protectedFlag = isProtected ? "1" : "0"
let creator = creatorID ?? self.myPeerID
let payload = "\(room)|\(protectedFlag)|\(creator)"
let packet = BitchatPacket(
type: MessageType.roomAnnounce.rawValue,
senderID: Data(self.myPeerID.utf8),
recipientID: SpecialRecipients.broadcast,
timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
payload: Data(payload.utf8),
signature: nil,
ttl: 5 // Allow wider propagation for room announcements
)
bitchatLog("Announcing room \(room) protection status: \(isProtected)", category: "room")
self.broadcastPacket(packet)
}
}
func sendEncryptedRoomMessage(_ content: String, mentions: [String], room: String, roomKey: SymmetricKey) {
messageQueue.async { [weak self] in
guard let self = self else { return }
let nickname = self.delegate as? ChatViewModel
let senderNick = nickname?.nickname ?? self.myPeerID
// Encrypt the content
guard let contentData = content.data(using: .utf8) else { return }
do {
let sealedBox = try AES.GCM.seal(contentData, using: roomKey)
let encryptedData = sealedBox.combined!
// Create message with encrypted content
let message = BitchatMessage(
sender: senderNick,
content: "", // Empty placeholder since actual content is encrypted
timestamp: Date(),
isRelay: false,
originalSender: nil,
isPrivate: false,
recipientNickname: nil,
senderPeerID: self.myPeerID,
mentions: mentions.isEmpty ? nil : mentions,
room: room,
encryptedContent: encryptedData,
isEncrypted: true
)
if let messageData = message.toBinaryPayload() {
// Sign the message payload
let signature: Data?
do {
signature = try self.encryptionService.sign(messageData)
} catch {
signature = nil
}
let packet = BitchatPacket(
type: MessageType.message.rawValue,
senderID: Data(self.myPeerID.utf8),
recipientID: SpecialRecipients.broadcast,
timestamp: UInt64(Date().timeIntervalSince1970 * 1000),
payload: messageData,
signature: signature,
ttl: self.adaptiveTTL
)
self.broadcastPacket(packet)
bitchatLog("Sent encrypted message to room \(room)", category: "room")
}
} catch {
bitchatLog("Failed to encrypt room message: \(error)", category: "crypto")
}
}
}
private func sendAnnouncementToPeer(_ peerID: String) {
guard let vm = delegate as? ChatViewModel else { return }
@@ -1224,9 +1306,21 @@ class BluetoothMeshService: NSObject {
peerNicknames[senderID] = message.sender
peerNicknamesLock.unlock()
// Handle encrypted room messages
var finalContent = message.content
if message.isEncrypted, let room = message.room, let encryptedData = message.encryptedContent {
// Try to decrypt the content
if let decryptedContent = self.delegate?.decryptRoomMessage(encryptedData, room: room) {
finalContent = decryptedContent
} else {
// Unable to decrypt - show placeholder
finalContent = "[Encrypted message - password required]"
}
}
let messageWithPeerID = BitchatMessage(
sender: message.sender,
content: message.content,
content: finalContent,
timestamp: message.timestamp,
isRelay: message.isRelay,
originalSender: message.originalSender,
@@ -1234,7 +1328,9 @@ class BluetoothMeshService: NSObject {
recipientNickname: nil,
senderPeerID: senderID,
mentions: message.mentions,
room: message.room
room: message.room,
encryptedContent: message.encryptedContent,
isEncrypted: message.isEncrypted
)
DispatchQueue.main.async {
@@ -1664,6 +1760,30 @@ class BluetoothMeshService: NSObject {
self.broadcastPacket(relayPacket)
}
case .roomAnnounce:
if let payloadStr = String(data: packet.payload, encoding: .utf8) {
// Parse payload: room|isProtected|creatorID
let components = payloadStr.split(separator: "|").map(String.init)
if components.count >= 3 {
let room = components[0]
let isProtected = components[1] == "1"
let creatorID = components[2]
bitchatLog("Received room announcement: \(room) is \(isProtected ? "protected" : "public") by \(creatorID)", category: "room")
DispatchQueue.main.async {
self.delegate?.didReceivePasswordProtectedRoomAnnouncement(room, isProtected: isProtected, creatorID: creatorID)
}
// Relay announcement
if packet.ttl > 1 {
var relayPacket = packet
relayPacket.ttl -= 1
self.broadcastPacket(relayPacket)
}
}
}
default:
break
}
+180 -3
View File
@@ -10,6 +10,7 @@ import Foundation
import SwiftUI
import Combine
import CryptoKit
import CommonCrypto
#if os(iOS)
import UIKit
#endif
@@ -40,12 +41,21 @@ class ChatViewModel: ObservableObject {
@Published var roomMessages: [String: [BitchatMessage]] = [:] // room -> messages
@Published var unreadRoomMessages: [String: Int] = [:] // room -> unread count
@Published var roomMembers: [String: Set<String>] = [:] // room -> set of peer IDs who have sent messages
@Published var roomPasswords: [String: String] = [:] // room -> password (stored locally only)
@Published var roomKeys: [String: SymmetricKey] = [:] // room -> derived encryption key
@Published var passwordProtectedRooms: Set<String> = [] // Set of rooms that require passwords
@Published var roomCreators: [String: String] = [:] // room -> creator peerID
@Published var showPasswordPrompt: Bool = false
@Published var passwordPromptRoom: String? = nil
let meshService = BluetoothMeshService()
private let userDefaults = UserDefaults.standard
private let nicknameKey = "bitchat.nickname"
private let favoritesKey = "bitchat.favorites"
private let joinedRoomsKey = "bitchat.joinedRooms"
private let passwordProtectedRoomsKey = "bitchat.passwordProtectedRooms"
private let roomCreatorsKey = "bitchat.roomCreators"
private let roomPasswordsKey = "bitchat.roomPasswords"
private var nicknameSaveTimer: Timer?
@Published var favoritePeers: Set<String> = [] // Now stores public key fingerprints instead of peer IDs
@@ -57,6 +67,7 @@ class ChatViewModel: ObservableObject {
loadNickname()
loadFavorites()
loadJoinedRooms()
loadRoomData()
meshService.delegate = self
// Log startup info
@@ -109,9 +120,53 @@ class ChatViewModel: ObservableObject {
userDefaults.synchronize()
}
func joinRoom(_ room: String) {
private func loadRoomData() {
// Load password protected rooms
if let savedProtectedRooms = userDefaults.stringArray(forKey: passwordProtectedRoomsKey) {
passwordProtectedRooms = Set(savedProtectedRooms)
}
// Load room creators
if let savedCreators = userDefaults.dictionary(forKey: roomCreatorsKey) as? [String: String] {
roomCreators = savedCreators
}
// Load room passwords (encrypted would be better, but keeping simple for now)
if let savedPasswords = userDefaults.dictionary(forKey: roomPasswordsKey) as? [String: String] {
roomPasswords = savedPasswords
// Derive keys for all saved passwords
for (room, password) in savedPasswords {
roomKeys[room] = deriveRoomKey(from: password, roomName: room)
}
}
}
private func saveRoomData() {
userDefaults.set(Array(passwordProtectedRooms), forKey: passwordProtectedRoomsKey)
userDefaults.set(roomCreators, forKey: roomCreatorsKey)
userDefaults.set(roomPasswords, forKey: roomPasswordsKey)
userDefaults.synchronize()
}
func joinRoom(_ room: String, password: String? = nil) {
// Ensure room starts with #
let roomTag = room.hasPrefix("#") ? room : "#\(room)"
// If room is password protected and we don't have the key yet
if passwordProtectedRooms.contains(roomTag) && roomKeys[roomTag] == nil {
if let password = password {
// Derive key from password
let key = deriveRoomKey(from: password, roomName: roomTag)
roomKeys[roomTag] = key
roomPasswords[roomTag] = password // Store for convenience (local only)
} else {
// Show password prompt
passwordPromptRoom = roomTag
showPasswordPrompt = true
return
}
}
joinedRooms.insert(roomTag)
saveJoinedRooms()
@@ -144,6 +199,87 @@ class ChatViewModel: ObservableObject {
unreadRoomMessages.removeValue(forKey: room)
roomMessages.removeValue(forKey: room)
roomMembers.removeValue(forKey: room)
roomKeys.removeValue(forKey: room)
roomPasswords.removeValue(forKey: room)
}
// Password management
func setRoomPassword(_ password: String, for room: String) {
guard joinedRooms.contains(room) else { return }
// If room has no creator yet, make current user the creator
if roomCreators[room] == nil {
roomCreators[room] = meshService.myPeerID
}
// Only room creator can set password
guard roomCreators[room] == meshService.myPeerID else {
bitchatLog("Only room creator can set password", category: "room")
return
}
// Derive encryption key from password
let key = deriveRoomKey(from: password, roomName: room)
roomKeys[room] = key
roomPasswords[room] = password
passwordProtectedRooms.insert(room)
// Save room data
saveRoomData()
// Announce that this room is now password protected
meshService.announcePasswordProtectedRoom(room, creatorID: meshService.myPeerID)
bitchatLog("Set password for room \(room)", category: "room")
}
func removeRoomPassword(for room: String) {
// Only room creator can remove password
guard roomCreators[room] == meshService.myPeerID else {
bitchatLog("Only room creator can remove password", category: "room")
return
}
roomKeys.removeValue(forKey: room)
roomPasswords.removeValue(forKey: room)
passwordProtectedRooms.remove(room)
// Save room data
saveRoomData()
// Announce that this room is no longer password protected
meshService.announcePasswordProtectedRoom(room, isProtected: false, creatorID: meshService.myPeerID)
bitchatLog("Removed password for room \(room)", category: "room")
}
private func deriveRoomKey(from password: String, roomName: String) -> SymmetricKey {
// Use PBKDF2 to derive a key from the password
let salt = roomName.data(using: .utf8)! // Use room name as salt for consistency
let keyData = pbkdf2(password: password, salt: salt, iterations: 100000, keyLength: 32)
return SymmetricKey(data: keyData)
}
private func pbkdf2(password: String, salt: Data, iterations: Int, keyLength: Int) -> Data {
var derivedKey = Data(count: keyLength)
let passwordData = password.data(using: .utf8)!
derivedKey.withUnsafeMutableBytes { derivedKeyBytes in
salt.withUnsafeBytes { saltBytes in
passwordData.withUnsafeBytes { passwordBytes in
CCKeyDerivationPBKDF(
CCPBKDFAlgorithm(kCCPBKDF2),
passwordBytes.baseAddress, passwordData.count,
saltBytes.baseAddress, salt.count,
CCPseudoRandomAlgorithm(kCCPRFHmacAlgSHA256),
UInt32(iterations),
derivedKeyBytes.baseAddress, keyLength
)
}
}
}
return derivedKey
}
func switchToRoom(_ room: String?) {
@@ -271,8 +407,14 @@ class ChatViewModel: ObservableObject {
}
}
// Send via mesh with mentions and room
meshService.sendMessage(content, mentions: mentions, room: messageRoom)
// Check if room is password protected and encrypt if needed
if let room = messageRoom, roomKeys[room] != nil {
// Send encrypted room message
meshService.sendEncryptedRoomMessage(content, mentions: mentions, room: room, roomKey: roomKeys[room]!)
} else {
// Send via mesh with mentions and room (unencrypted)
meshService.sendMessage(content, mentions: mentions, room: messageRoom)
}
}
}
@@ -644,6 +786,41 @@ extension ChatViewModel: BitchatDelegate {
}
}
func didReceivePasswordProtectedRoomAnnouncement(_ room: String, isProtected: Bool, creatorID: String?) {
if isProtected {
passwordProtectedRooms.insert(room)
if let creator = creatorID {
roomCreators[room] = creator
}
} else {
passwordProtectedRooms.remove(room)
// If we're in this room and it's no longer protected, clear the key
roomKeys.removeValue(forKey: room)
roomPasswords.removeValue(forKey: room)
}
// Save updated room data
saveRoomData()
bitchatLog("Room \(room) is now \(isProtected ? "password protected" : "public")", category: "room")
}
func decryptRoomMessage(_ encryptedContent: Data, room: String) -> String? {
guard let roomKey = roomKeys[room] else {
bitchatLog("No key available for encrypted room \(room)", category: "room")
return nil
}
do {
let sealedBox = try AES.GCM.SealedBox(combined: encryptedContent)
let decryptedData = try AES.GCM.open(sealedBox, using: roomKey)
return String(data: decryptedData, encoding: .utf8)
} catch {
bitchatLog("Failed to decrypt room message: \(error)", category: "crypto")
return nil
}
}
func didReceiveMessage(_ message: BitchatMessage) {
bitchatLog("Received message from \(message.sender), room: \(message.room ?? "nil"), senderPeerID: \(message.senderPeerID ?? "nil")", category: "message")
+87 -14
View File
@@ -18,6 +18,11 @@ struct ContentView: View {
@State private var showSidebar = false
@State private var sidebarDragOffset: CGFloat = 0
@State private var showAppInfo = false
@State private var showPasswordInput = false
@State private var passwordInputRoom: String? = nil
@State private var passwordInput = ""
@State private var showPasswordPrompt = false
@State private var passwordPromptInput = ""
private var backgroundColor: Color {
colorScheme == .dark ? Color.black : Color.white
@@ -160,6 +165,40 @@ struct ContentView: View {
.sheet(isPresented: $showAppInfo) {
AppInfoView()
}
.alert("Set Room Password", isPresented: $showPasswordInput) {
SecureField("Password", text: $passwordInput)
Button("Cancel", role: .cancel) {
passwordInput = ""
passwordInputRoom = nil
}
Button("Set Password") {
if let room = passwordInputRoom, !passwordInput.isEmpty {
viewModel.setRoomPassword(passwordInput, for: room)
passwordInput = ""
passwordInputRoom = nil
}
}
} message: {
Text("Enter a password to protect \(passwordInputRoom ?? "room"). Others will need this password to read messages.")
}
.alert("Enter Room Password", isPresented: Binding(
get: { viewModel.showPasswordPrompt },
set: { viewModel.showPasswordPrompt = $0 }
)) {
SecureField("Password", text: $passwordPromptInput)
Button("Cancel", role: .cancel) {
passwordPromptInput = ""
viewModel.passwordPromptRoom = nil
}
Button("Join") {
if let room = viewModel.passwordPromptRoom, !passwordPromptInput.isEmpty {
viewModel.joinRoom(room, password: passwordPromptInput)
passwordPromptInput = ""
}
}
} message: {
Text("This room is password protected. Enter the password to join.")
}
}
private var headerView: some View {
@@ -517,6 +556,13 @@ struct ContentView: View {
}
}) {
HStack {
// Lock icon for password protected rooms
if viewModel.passwordProtectedRooms.contains(room) {
Image(systemName: "lock.fill")
.font(.system(size: 10))
.foregroundColor(secondaryTextColor)
}
Text(room)
.font(.system(size: 14, design: .monospaced))
.foregroundColor(viewModel.currentRoom == room ? Color.blue : textColor)
@@ -534,22 +580,49 @@ struct ContentView: View {
.clipShape(Capsule())
}
// Leave button
// Room controls
if viewModel.currentRoom == room {
Button(action: {
viewModel.leaveRoom(room)
}) {
Text("leave")
.font(.system(size: 10, design: .monospaced))
.foregroundColor(secondaryTextColor)
.padding(.horizontal, 8)
.padding(.vertical, 2)
.overlay(
RoundedRectangle(cornerRadius: 4)
.stroke(secondaryTextColor.opacity(0.5), lineWidth: 1)
)
HStack(spacing: 4) {
// Password button for room creator
if viewModel.roomCreators[room] == viewModel.meshService.myPeerID {
Button(action: {
// Toggle password protection
if viewModel.passwordProtectedRooms.contains(room) {
viewModel.removeRoomPassword(for: room)
} else {
// Show password input
showPasswordInput = true
passwordInputRoom = room
}
}) {
Image(systemName: viewModel.passwordProtectedRooms.contains(room) ? "lock.open" : "lock")
.font(.system(size: 10))
.foregroundColor(secondaryTextColor)
.padding(4)
.overlay(
RoundedRectangle(cornerRadius: 4)
.stroke(secondaryTextColor.opacity(0.5), lineWidth: 1)
)
}
.buttonStyle(.plain)
}
// Leave button
Button(action: {
viewModel.leaveRoom(room)
}) {
Text("leave")
.font(.system(size: 10, design: .monospaced))
.foregroundColor(secondaryTextColor)
.padding(.horizontal, 8)
.padding(.vertical, 2)
.overlay(
RoundedRectangle(cornerRadius: 4)
.stroke(secondaryTextColor.opacity(0.5), lineWidth: 1)
)
}
.buttonStyle(.plain)
}
.buttonStyle(.plain)
}
}
.padding(.horizontal, 12)