Hi, I'd like to lazily enable encryption on my NWListener. Basically, right now, I've implemented encryption in the NWListener's initialization phase, like so:
import CryptoKit
import Network
extension NWParameters {
// Create parameters for use with Connection and Listener.
convenience init(secret: String, identity: String) {
let tcpOptions = NWProtocolTCP.Options()
tcpOptions.enableKeepalive = true
tcpOptions.keepaliveIdle = 2
let tlsOptions = NWProtocolTLS.Options()
let authenticationKey = SymmetricKey(data: secret.data(using: .utf8)!)
var authenticationCode = HMAC<SHA256>.authenticationCode(for: identity.data(using: .utf8)!, using: authenticationKey)
let authenticationDispatchData = withUnsafeBytes(of: &authenticationCode) { (ptr: UnsafeRawBufferPointer) in
DispatchData(bytes: ptr)
}
let psk = authenticationDispatchData as __DispatchData
var identityData = identity.data(using: .unicode)!
let identityDispatchData = withUnsafeBytes(of: &identityData) { (ptr: UnsafeRawBufferPointer) in
DispatchData(bytes: ptr)
}
let psk_identity = identityDispatchData as __DispatchData
sec_protocol_options_add_pre_shared_key(
tlsOptions.securityProtocolOptions, psk, psk_identity
)
let ciphersuite = tls_ciphersuite_t(rawValue: TLS_PSK_WITH_AES_128_GCM_SHA256)! sec_protocol_options_append_tls_ciphersuite(
tlsOptions.securityProtocolOptions, ciphersuite
)
self.init(tls: tlsOptions, tcp: tcpOptions)
self.includePeerToPeer = true
let customProtocol = NWProtocolFramer.Options(definition: TLVMessageProtocol.definition)
self.defaultProtocolStack.applicationProtocols.insert(customProtocol, at: 0)
}
}
The preshared key (secret) would be a combination of the user's and a peer's CLBeacon major/minor. However, I want to be able to create an NWListener before detecting a peer's CLBeacon, since it's quite a heavy and time-consuming operation.
Is there a way to create an NWListener first, and then give it the encryption / preshared key later?