Files
bitchat/bitchat/Services/BLE/BLENoisePayloadFactory.swift
T
jackandGitHub 2d96fd99a1 Encrypt private media before BLE fragmentation (#1434)
Closes the last cleartext private-content path over BLE: private DM images/voice were sent as plaintext signed fileTransfer packets, TTL-relayed across the mesh, so every relay saw the full bytes. Now the complete BitchatFilePacket is encrypted as a single Noise AEAD message (inner type 0x20, matching Android) and the opaque ciphertext is fragmented. Adds an authenticated in-session capability proof (0x21 TLV: capabilities + Ed25519 key), TOFU-style downgrade pinning, a per-send consent dialog for the signed-cleartext fallback to legacy peers, and a cancellation/admission registry so cancel/delete cannot race a deferred cleartext send.

Android wire constants (0x20 / 0x21 / capability bit 8) confirmed shipping. The 256-fragment preflight cap applies only to the directed fileTransfer migration fallback; encrypted media to capable peers uses the full receiver ceiling.

Rebased over #1428/#1349: identity reads go through BLELocalIdentityStateStore; the session-bound authenticated signing-key check and the announce-path TOFU pin are kept as complementary checks. Full local suite green (1744+197 tests).
2026-07-26 12:17:22 +02:00

36 lines
1.2 KiB
Swift

import Foundation
enum BLENoisePayloadFactory {
static func privateMessage(content: String, messageID: String) -> Data? {
guard let payload = PrivateMessagePacket(messageID: messageID, content: content).encode() else {
return nil
}
return typedPayload(.privateMessage, payload: payload)
}
static func readReceipt(originalMessageID: String) -> Data {
typedPayload(.readReceipt, payload: Data(originalMessageID.utf8))
}
static func delivered(messageID: String) -> Data {
typedPayload(.delivered, payload: Data(messageID.utf8))
}
static func privateFile(_ filePacket: BitchatFilePacket) -> Data? {
guard let payload = filePacket.encode() else { return nil }
return typedPayload(.privateFile, payload: payload)
}
static func authenticatedPeerState(_ state: AuthenticatedPeerStatePacket) -> Data? {
guard let payload = state.encode() else { return nil }
return typedPayload(.authenticatedPeerState, payload: payload)
}
static func typedPayload(_ type: NoisePayloadType, payload: Data) -> Data {
var typed = Data([type.rawValue])
typed.append(payload)
return typed
}
}