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Implement Noise Protocol Framework and peer ID rotation for enhanced security and privacy

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This major update replaces the basic encryption with the Noise Protocol Framework
and adds ephemeral peer ID rotation for enhanced privacy.

Key Changes:

Security Infrastructure:
- Implemented Noise Protocol Framework (XX handshake pattern)
- End-to-end encryption with forward secrecy and identity hiding
- Session management with automatic rekey support
- Channel encryption with password-derived keys

Privacy Enhancements:
- Ephemeral peer ID rotation (5-15 minute random intervals)
- Persistent identity through public key fingerprints
- Favorites and verification persist across ID rotations
- Block list based on fingerprints, not ephemeral IDs

Core Components Added:
- NoiseEncryptionService: Main encryption service
- NoiseSession: Individual peer session management
- NoiseChannelEncryption: Password-protected channel support
- SecureIdentityStateManager: Persistent identity storage
- FingerprintView: Visual fingerprint verification UI

Bug Fixes:
- Fixed handshake storm with tie-breaker mechanism
- Fixed missing connect messages during peer rotation
- Fixed delivery ACK compression issues
- Fixed race conditions in message queue
- Fixed nickname resolution for rotated peer IDs

Testing:
- Comprehensive test suite for Noise implementation
- Security validator tests
- Channel encryption tests
- Identity persistence tests
- Rate limiter tests

Documentation:
- BRING_THE_NOISE.md: Technical implementation details
- Updated WHITEPAPER.md: Simplified and focused on core innovations
- Removed temporary debug documentation

The implementation maintains backward compatibility while significantly
improving security and privacy. All existing features (channels, private
messages, favorites, blocking) work seamlessly with the new system.
This commit is contained in:
jack
2025-07-15 13:15:31 +02:00
parent 6d39222ea0
commit 3070a4d307
42 changed files with 10952 additions and 2233 deletions
Download Patch File Download Diff File Expand all files Collapse all files
bitchat/Protocols/BinaryProtocol.swift
+42 -21
View File
@@ -49,17 +49,22 @@ struct BinaryProtocol {
static func encode(_ packet: BitchatPacket) -> Data? {
var data = Data()
// Try to compress payload if beneficial
var payload = packet.payload
var originalPayloadSize: UInt16? = nil
var isCompressed = false
if CompressionUtil.shouldCompress(payload),
let compressedPayload = CompressionUtil.compress(payload) {
// Store original size for decompression (2 bytes after payload)
originalPayloadSize = UInt16(payload.count)
payload = compressedPayload
isCompressed = true
if CompressionUtil.shouldCompress(payload) {
if let compressedPayload = CompressionUtil.compress(payload) {
// Store original size for decompression (2 bytes after payload)
originalPayloadSize = UInt16(payload.count)
payload = compressedPayload
isCompressed = true
} else {
}
} else {
}
// Header
@@ -88,6 +93,8 @@ struct BinaryProtocol {
// Payload length (2 bytes, big-endian) - includes original size if compressed
let payloadDataSize = payload.count + (isCompressed ? 2 : 0)
let payloadLength = UInt16(payloadDataSize)
data.append(UInt8((payloadLength >> 8) & 0xFF))
data.append(UInt8(payloadLength & 0xFF))
@@ -120,37 +127,49 @@ struct BinaryProtocol {
data.append(signature.prefix(signatureSize))
}
return data
// Apply padding to standard block sizes for traffic analysis resistance
let optimalSize = MessagePadding.optimalBlockSize(for: data.count)
let paddedData = MessagePadding.pad(data, toSize: optimalSize)
return paddedData
}
// Decode binary data to BitchatPacket
static func decode(_ data: Data) -> BitchatPacket? {
guard data.count >= headerSize + senderIDSize else { return nil }
// Remove padding first
let unpaddedData = MessagePadding.unpad(data)
guard unpaddedData.count >= headerSize + senderIDSize else {
return nil
}
var offset = 0
// Header
let version = data[offset]; offset += 1
let version = unpaddedData[offset]; offset += 1
// Only support version 1
guard version == 1 else { return nil }
let type = data[offset]; offset += 1
let ttl = data[offset]; offset += 1
let type = unpaddedData[offset]; offset += 1
let ttl = unpaddedData[offset]; offset += 1
// Timestamp
let timestampData = data[offset..<offset+8]
let timestampData = unpaddedData[offset..<offset+8]
let timestamp = timestampData.reduce(0) { result, byte in
(result << 8) | UInt64(byte)
}
offset += 8
// Flags
let flags = data[offset]; offset += 1
let flags = unpaddedData[offset]; offset += 1
let hasRecipient = (flags & Flags.hasRecipient) != 0
let hasSignature = (flags & Flags.hasSignature) != 0
let isCompressed = (flags & Flags.isCompressed) != 0
// Payload length
let payloadLengthData = data[offset..<offset+2]
let payloadLengthData = unpaddedData[offset..<offset+2]
let payloadLength = payloadLengthData.reduce(0) { result, byte in
(result << 8) | UInt16(byte)
}
@@ -165,16 +184,18 @@ struct BinaryProtocol {
expectedSize += signatureSize
}
guard data.count >= expectedSize else { return nil }
guard unpaddedData.count >= expectedSize else {
return nil
}
// SenderID
let senderID = data[offset..<offset+senderIDSize]
let senderID = unpaddedData[offset..<offset+senderIDSize]
offset += senderIDSize
// RecipientID
var recipientID: Data?
if hasRecipient {
recipientID = data[offset..<offset+recipientIDSize]
recipientID = unpaddedData[offset..<offset+recipientIDSize]
offset += recipientIDSize
}
@@ -183,14 +204,14 @@ struct BinaryProtocol {
if isCompressed {
// First 2 bytes are original size
guard Int(payloadLength) >= 2 else { return nil }
let originalSizeData = data[offset..<offset+2]
let originalSizeData = unpaddedData[offset..<offset+2]
let originalSize = Int(originalSizeData.reduce(0) { result, byte in
(result << 8) | UInt16(byte)
})
offset += 2
// Compressed payload
let compressedPayload = data[offset..<offset+Int(payloadLength)-2]
let compressedPayload = unpaddedData[offset..<offset+Int(payloadLength)-2]
offset += Int(payloadLength) - 2
// Decompress
@@ -199,14 +220,14 @@ struct BinaryProtocol {
}
payload = decompressedPayload
} else {
payload = data[offset..<offset+Int(payloadLength)]
payload = unpaddedData[offset..<offset+Int(payloadLength)]
offset += Int(payloadLength)
}
// Signature
var signature: Data?
if hasSignature {
signature = data[offset..<offset+signatureSize]
signature = unpaddedData[offset..<offset+signatureSize]
}
return BitchatPacket(
bitchat/Protocols/BitchatProtocol.swift
+228 -4
View File
@@ -41,9 +41,20 @@ struct MessagePadding {
// Last byte tells us how much padding to remove
let paddingLength = Int(data[data.count - 1])
guard paddingLength > 0 && paddingLength <= data.count else { return data }
guard paddingLength > 0 && paddingLength <= data.count else {
// Debug logging for 243-byte packets
if data.count == 243 {
}
return data
}
return data.prefix(data.count - paddingLength)
let result = data.prefix(data.count - paddingLength)
// Debug logging for 243-byte packets
if data.count == 243 {
}
return result
}
// Find optimal block size for data
@@ -66,7 +77,7 @@ struct MessagePadding {
enum MessageType: UInt8 {
case announce = 0x01
case keyExchange = 0x02
// 0x02 was legacy keyExchange - removed
case leave = 0x03
case message = 0x04 // All user messages (private and broadcast)
case fragmentStart = 0x05
@@ -77,6 +88,40 @@ enum MessageType: UInt8 {
case deliveryAck = 0x0A // Acknowledge message received
case deliveryStatusRequest = 0x0B // Request delivery status update
case readReceipt = 0x0C // Message has been read/viewed
// Noise Protocol messages
case noiseHandshakeInit = 0x10 // Noise handshake initiation
case noiseHandshakeResp = 0x11 // Noise handshake response
case noiseEncrypted = 0x12 // Noise encrypted transport message
case noiseIdentityAnnounce = 0x13 // Announce static public key for discovery
case channelKeyVerifyRequest = 0x14 // Request key verification for a channel
case channelKeyVerifyResponse = 0x15 // Response to key verification request
case channelPasswordUpdate = 0x16 // Distribute new password to channel members
case channelMetadata = 0x17 // Announce channel creator and metadata
var description: String {
switch self {
case .announce: return "announce"
case .leave: return "leave"
case .message: return "message"
case .fragmentStart: return "fragmentStart"
case .fragmentContinue: return "fragmentContinue"
case .fragmentEnd: return "fragmentEnd"
case .channelAnnounce: return "channelAnnounce"
case .channelRetention: return "channelRetention"
case .deliveryAck: return "deliveryAck"
case .deliveryStatusRequest: return "deliveryStatusRequest"
case .readReceipt: return "readReceipt"
case .noiseHandshakeInit: return "noiseHandshakeInit"
case .noiseHandshakeResp: return "noiseHandshakeResp"
case .noiseEncrypted: return "noiseEncrypted"
case .noiseIdentityAnnounce: return "noiseIdentityAnnounce"
case .channelKeyVerifyRequest: return "channelKeyVerifyRequest"
case .channelKeyVerifyResponse: return "channelKeyVerifyResponse"
case .channelPasswordUpdate: return "channelPasswordUpdate"
case .channelMetadata: return "channelMetadata"
}
}
}
// Special recipient ID for broadcast messages
@@ -109,7 +154,17 @@ struct BitchatPacket: Codable {
init(type: UInt8, ttl: UInt8, senderID: String, payload: Data) {
self.version = 1
self.type = type
self.senderID = senderID.data(using: .utf8)!
// Convert hex string peer ID to binary data (8 bytes)
var senderData = Data()
var tempID = senderID
while tempID.count >= 2 {
let hexByte = String(tempID.prefix(2))
if let byte = UInt8(hexByte, radix: 16) {
senderData.append(byte)
}
tempID = String(tempID.dropFirst(2))
}
self.senderID = senderData
self.recipientID = nil
self.timestamp = UInt64(Date().timeIntervalSince1970 * 1000) // milliseconds
self.payload = payload
@@ -182,6 +237,151 @@ struct ReadReceipt: Codable {
}
}
// Channel key verification request
struct ChannelKeyVerifyRequest: Codable {
let channel: String
let requesterID: String
let keyCommitment: String // SHA256 hash of the key they have
let timestamp: Date
init(channel: String, requesterID: String, keyCommitment: String) {
self.channel = channel
self.requesterID = requesterID
self.keyCommitment = keyCommitment
self.timestamp = Date()
}
func encode() -> Data? {
return try? JSONEncoder().encode(self)
}
static func decode(from data: Data) -> ChannelKeyVerifyRequest? {
try? JSONDecoder().decode(ChannelKeyVerifyRequest.self, from: data)
}
}
// Channel key verification response
struct ChannelKeyVerifyResponse: Codable {
let channel: String
let responderID: String
let verified: Bool // Whether the key commitment matches
let timestamp: Date
init(channel: String, responderID: String, verified: Bool) {
self.channel = channel
self.responderID = responderID
self.verified = verified
self.timestamp = Date()
}
func encode() -> Data? {
return try? JSONEncoder().encode(self)
}
static func decode(from data: Data) -> ChannelKeyVerifyResponse? {
try? JSONDecoder().decode(ChannelKeyVerifyResponse.self, from: data)
}
}
// Channel password update (sent by owner to members)
struct ChannelPasswordUpdate: Codable {
let channel: String
let ownerID: String // Deprecated, kept for backward compatibility
let ownerFingerprint: String // Noise protocol fingerprint of owner
let encryptedPassword: Data // New password encrypted with recipient's Noise session
let newKeyCommitment: String // SHA256 of new key for verification
let timestamp: Date
init(channel: String, ownerID: String, ownerFingerprint: String, encryptedPassword: Data, newKeyCommitment: String) {
self.channel = channel
self.ownerID = ownerID
self.ownerFingerprint = ownerFingerprint
self.encryptedPassword = encryptedPassword
self.newKeyCommitment = newKeyCommitment
self.timestamp = Date()
}
func encode() -> Data? {
return try? JSONEncoder().encode(self)
}
static func decode(from data: Data) -> ChannelPasswordUpdate? {
try? JSONDecoder().decode(ChannelPasswordUpdate.self, from: data)
}
}
// Channel metadata announcement
struct ChannelMetadata: Codable {
let channel: String
let creatorID: String
let creatorFingerprint: String // Noise protocol fingerprint
let createdAt: Date
let isPasswordProtected: Bool
let keyCommitment: String? // SHA256 of channel key if password-protected
init(channel: String, creatorID: String, creatorFingerprint: String, isPasswordProtected: Bool, keyCommitment: String?) {
self.channel = channel
self.creatorID = creatorID
self.creatorFingerprint = creatorFingerprint
self.createdAt = Date()
self.isPasswordProtected = isPasswordProtected
self.keyCommitment = keyCommitment
}
func encode() -> Data? {
return try? JSONEncoder().encode(self)
}
static func decode(from data: Data) -> ChannelMetadata? {
try? JSONDecoder().decode(ChannelMetadata.self, from: data)
}
}
// MARK: - Peer Identity Rotation
// Enhanced identity announcement with rotation support
struct NoiseIdentityAnnouncement: Codable {
let peerID: String // Current ephemeral peer ID
let publicKey: Data // Noise static public key
let nickname: String // Current nickname
let timestamp: Date // When this binding was created
let previousPeerID: String? // Previous peer ID (for smooth transition)
let signature: Data // Signature proving ownership
init(peerID: String, publicKey: Data, nickname: String, previousPeerID: String? = nil, signature: Data) {
self.peerID = peerID
self.publicKey = publicKey
self.nickname = nickname
self.timestamp = Date()
self.previousPeerID = previousPeerID
self.signature = signature
}
func encode() -> Data? {
return try? JSONEncoder().encode(self)
}
static func decode(from data: Data) -> NoiseIdentityAnnouncement? {
try? JSONDecoder().decode(NoiseIdentityAnnouncement.self, from: data)
}
}
// Binding between ephemeral peer ID and cryptographic identity
struct PeerIdentityBinding {
let currentPeerID: String // Current ephemeral ID
let fingerprint: String // Permanent cryptographic identity
let publicKey: Data // Noise static public key
let nickname: String // Last known nickname
let bindingTimestamp: Date // When this binding was created
let signature: Data // Cryptographic proof of binding
// Verify the binding signature
func verify() -> Bool {
// TODO: Implement signature verification
return true
}
}
// Delivery status for messages
enum DeliveryStatus: Codable, Equatable {
case sending
@@ -260,6 +460,14 @@ protocol BitchatDelegate: AnyObject {
func didReceiveDeliveryAck(_ ack: DeliveryAck)
func didReceiveReadReceipt(_ receipt: ReadReceipt)
func didUpdateMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus)
// Channel key verification methods
func didReceiveChannelKeyVerifyRequest(_ request: ChannelKeyVerifyRequest, from peerID: String)
func didReceiveChannelKeyVerifyResponse(_ response: ChannelKeyVerifyResponse, from peerID: String)
func didReceiveChannelPasswordUpdate(_ update: ChannelPasswordUpdate, from peerID: String)
// Channel metadata methods
func didReceiveChannelMetadata(_ metadata: ChannelMetadata, from peerID: String)
}
// Provide default implementation to make it effectively optional
@@ -296,4 +504,20 @@ extension BitchatDelegate {
func didUpdateMessageDeliveryStatus(_ messageID: String, status: DeliveryStatus) {
// Default empty implementation
}
func didReceiveChannelKeyVerifyRequest(_ request: ChannelKeyVerifyRequest, from peerID: String) {
// Default empty implementation
}
func didReceiveChannelKeyVerifyResponse(_ response: ChannelKeyVerifyResponse, from peerID: String) {
// Default empty implementation
}
func didReceiveChannelPasswordUpdate(_ update: ChannelPasswordUpdate, from peerID: String) {
// Default empty implementation
}
func didReceiveChannelMetadata(_ metadata: ChannelMetadata, from peerID: String) {
// Default empty implementation
}
}