fix(mac): add tailnet discovery fallback and debug CLI

This commit is contained in:
Peter Steinberger
2026-01-10 23:39:14 +01:00
parent c731a87d07
commit 621f710d60
19 changed files with 759 additions and 50 deletions

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import ClawdbotKit
import Foundation
import Network
public enum BridgeEndpointID {
public static func stableID(_ endpoint: NWEndpoint) -> String {
switch endpoint {
case let .service(name, type, domain, _):
// Keep stable across encoded/decoded differences (e.g. \032 for spaces).
let normalizedName = Self.normalizeServiceNameForID(name)
return "\(type)|\(domain)|\(normalizedName)"
default:
return String(describing: endpoint)
}
}
public static func prettyDescription(_ endpoint: NWEndpoint) -> String {
BonjourEscapes.decode(String(describing: endpoint))
}
private static func normalizeServiceNameForID(_ rawName: String) -> String {
let decoded = BonjourEscapes.decode(rawName)
let normalized = decoded.split(whereSeparator: \.isWhitespace).joined(separator: " ")
return normalized.trimmingCharacters(in: .whitespacesAndNewlines)
}
}

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import ClawdbotKit
import Foundation
import Network
import Observation
import OSLog
@MainActor
@Observable
public final class GatewayDiscoveryModel {
public struct LocalIdentity: Equatable, Sendable {
public var hostTokens: Set<String>
public var displayTokens: Set<String>
public init(hostTokens: Set<String>, displayTokens: Set<String>) {
self.hostTokens = hostTokens
self.displayTokens = displayTokens
}
}
public struct DiscoveredGateway: Identifiable, Equatable, Sendable {
public var id: String { self.stableID }
public var displayName: String
public var lanHost: String?
public var tailnetDns: String?
public var sshPort: Int
public var gatewayPort: Int?
public var cliPath: String?
public var stableID: String
public var debugID: String
public var isLocal: Bool
public init(
displayName: String,
lanHost: String? = nil,
tailnetDns: String? = nil,
sshPort: Int,
gatewayPort: Int? = nil,
cliPath: String? = nil,
stableID: String,
debugID: String,
isLocal: Bool)
{
self.displayName = displayName
self.lanHost = lanHost
self.tailnetDns = tailnetDns
self.sshPort = sshPort
self.gatewayPort = gatewayPort
self.cliPath = cliPath
self.stableID = stableID
self.debugID = debugID
self.isLocal = isLocal
}
}
public var gateways: [DiscoveredGateway] = []
public var statusText: String = "Idle"
private var browsers: [String: NWBrowser] = [:]
private var resultsByDomain: [String: Set<NWBrowser.Result>] = [:]
private var gatewaysByDomain: [String: [DiscoveredGateway]] = [:]
private var statesByDomain: [String: NWBrowser.State] = [:]
private var localIdentity: LocalIdentity
private let localDisplayName: String?
private let filterLocalGateways: Bool
private var resolvedTXTByID: [String: [String: String]] = [:]
private var pendingTXTResolvers: [String: GatewayTXTResolver] = [:]
private var wideAreaFallbackTask: Task<Void, Never>?
private var wideAreaFallbackGateways: [DiscoveredGateway] = []
private let logger = Logger(subsystem: "com.clawdbot", category: "gateway-discovery")
public init(
localDisplayName: String? = nil,
filterLocalGateways: Bool = true)
{
self.localDisplayName = localDisplayName
self.filterLocalGateways = filterLocalGateways
self.localIdentity = Self.buildLocalIdentityFast(displayName: localDisplayName)
self.refreshLocalIdentity()
}
public func start() {
if !self.browsers.isEmpty { return }
for domain in ClawdbotBonjour.bridgeServiceDomains {
let params = NWParameters.tcp
params.includePeerToPeer = true
let browser = NWBrowser(
for: .bonjour(type: ClawdbotBonjour.bridgeServiceType, domain: domain),
using: params)
browser.stateUpdateHandler = { [weak self] state in
Task { @MainActor in
guard let self else { return }
self.statesByDomain[domain] = state
self.updateStatusText()
}
}
browser.browseResultsChangedHandler = { [weak self] results, _ in
Task { @MainActor in
guard let self else { return }
self.resultsByDomain[domain] = results
self.updateGateways(for: domain)
self.recomputeGateways()
}
}
self.browsers[domain] = browser
browser.start(queue: DispatchQueue(label: "com.clawdbot.macos.gateway-discovery.\(domain)"))
}
self.scheduleWideAreaFallback()
}
public func stop() {
for browser in self.browsers.values {
browser.cancel()
}
self.browsers = [:]
self.resultsByDomain = [:]
self.gatewaysByDomain = [:]
self.statesByDomain = [:]
self.resolvedTXTByID = [:]
self.pendingTXTResolvers.values.forEach { $0.cancel() }
self.pendingTXTResolvers = [:]
self.wideAreaFallbackTask?.cancel()
self.wideAreaFallbackTask = nil
self.wideAreaFallbackGateways = []
self.gateways = []
self.statusText = "Stopped"
}
private func recomputeGateways() {
var next = self.gatewaysByDomain.values
.flatMap(\.self)
.sorted { $0.displayName.localizedCaseInsensitiveCompare($1.displayName) == .orderedAscending }
if self.gatewaysByDomain[ClawdbotBonjour.wideAreaBridgeServiceDomain]?.isEmpty ?? true,
!self.wideAreaFallbackGateways.isEmpty
{
next.append(contentsOf: self.wideAreaFallbackGateways)
}
var seen = Set<String>()
let deduped = next.filter { gateway in
if seen.contains(gateway.stableID) { return false }
seen.insert(gateway.stableID)
return true
}
let sorted = deduped.sorted {
$0.displayName.localizedCaseInsensitiveCompare($1.displayName) == .orderedAscending
}
self.gateways = self.filterLocalGateways
? sorted.filter { !$0.isLocal }
: sorted
}
private func updateGateways(for domain: String) {
guard let results = self.resultsByDomain[domain] else {
self.gatewaysByDomain[domain] = []
return
}
self.gatewaysByDomain[domain] = results.compactMap { result -> DiscoveredGateway? in
guard case let .service(name, type, resultDomain, _) = result.endpoint else { return nil }
let decodedName = BonjourEscapes.decode(name)
let stableID = BridgeEndpointID.stableID(result.endpoint)
let resolvedTXT = self.resolvedTXTByID[stableID] ?? [:]
let txt = Self.txtDictionary(from: result).merging(
resolvedTXT,
uniquingKeysWith: { _, new in new })
let advertisedName = txt["displayName"]
.map(Self.prettifyInstanceName)
.flatMap { $0.isEmpty ? nil : $0 }
let prettyName =
advertisedName ?? Self.prettifyServiceName(decodedName)
let parsedTXT = Self.parseGatewayTXT(txt)
if parsedTXT.lanHost == nil || parsedTXT.tailnetDns == nil {
self.ensureTXTResolution(
stableID: stableID,
serviceName: name,
type: type,
domain: resultDomain)
}
let isLocal = Self.isLocalGateway(
lanHost: parsedTXT.lanHost,
tailnetDns: parsedTXT.tailnetDns,
displayName: prettyName,
serviceName: decodedName,
local: self.localIdentity)
return DiscoveredGateway(
displayName: prettyName,
lanHost: parsedTXT.lanHost,
tailnetDns: parsedTXT.tailnetDns,
sshPort: parsedTXT.sshPort,
gatewayPort: parsedTXT.gatewayPort,
cliPath: parsedTXT.cliPath,
stableID: stableID,
debugID: BridgeEndpointID.prettyDescription(result.endpoint),
isLocal: isLocal)
}
.sorted { $0.displayName.localizedCaseInsensitiveCompare($1.displayName) == .orderedAscending }
if domain == ClawdbotBonjour.wideAreaBridgeServiceDomain,
!(self.gatewaysByDomain[domain]?.isEmpty ?? true)
{
self.wideAreaFallbackGateways = []
}
}
private func scheduleWideAreaFallback() {
let domain = ClawdbotBonjour.wideAreaBridgeServiceDomain
guard self.wideAreaFallbackTask == nil else { return }
self.wideAreaFallbackTask = Task.detached(priority: .utility) { [weak self] in
guard let self else { return }
if Task.isCancelled { return }
let hasResults = await MainActor.run {
!(self.gatewaysByDomain[domain]?.isEmpty ?? true)
}
if hasResults { return }
let beacons = WideAreaGatewayDiscovery.discover(timeoutSeconds: 3.0)
if beacons.isEmpty { return }
await MainActor.run { [weak self] in
guard let self else { return }
self.wideAreaFallbackGateways = beacons.map { beacon in
let stableID = "wide-area|\(domain)|\(beacon.instanceName)"
let isLocal = Self.isLocalGateway(
lanHost: beacon.lanHost,
tailnetDns: beacon.tailnetDns,
displayName: beacon.displayName,
serviceName: beacon.instanceName,
local: self.localIdentity)
return DiscoveredGateway(
displayName: beacon.displayName,
lanHost: beacon.lanHost,
tailnetDns: beacon.tailnetDns,
sshPort: beacon.sshPort ?? 22,
gatewayPort: beacon.gatewayPort,
cliPath: beacon.cliPath,
stableID: stableID,
debugID: "\(beacon.instanceName)@\(beacon.host):\(beacon.port)",
isLocal: isLocal)
}
self.recomputeGateways()
}
}
}
private func updateGatewaysForAllDomains() {
for domain in self.resultsByDomain.keys {
self.updateGateways(for: domain)
}
}
private func updateStatusText() {
let states = Array(self.statesByDomain.values)
if states.isEmpty {
self.statusText = self.browsers.isEmpty ? "Idle" : "Setup"
return
}
if let failed = states.first(where: { state in
if case .failed = state { return true }
return false
}) {
if case let .failed(err) = failed {
self.statusText = "Failed: \(err)"
return
}
}
if let waiting = states.first(where: { state in
if case .waiting = state { return true }
return false
}) {
if case let .waiting(err) = waiting {
self.statusText = "Waiting: \(err)"
return
}
}
if states.contains(where: { if case .ready = $0 { true } else { false } }) {
self.statusText = "Searching…"
return
}
if states.contains(where: { if case .setup = $0 { true } else { false } }) {
self.statusText = "Setup"
return
}
self.statusText = "Searching…"
}
private static func txtDictionary(from result: NWBrowser.Result) -> [String: String] {
var merged: [String: String] = [:]
if case let .bonjour(txt) = result.metadata {
merged.merge(txt.dictionary, uniquingKeysWith: { _, new in new })
}
if let endpointTxt = result.endpoint.txtRecord?.dictionary {
merged.merge(endpointTxt, uniquingKeysWith: { _, new in new })
}
return merged
}
public struct GatewayTXT: Equatable {
public var lanHost: String?
public var tailnetDns: String?
public var sshPort: Int
public var gatewayPort: Int?
public var cliPath: String?
}
public static func parseGatewayTXT(_ txt: [String: String]) -> GatewayTXT {
var lanHost: String?
var tailnetDns: String?
var sshPort = 22
var gatewayPort: Int?
var cliPath: String?
if let value = txt["lanHost"] {
let trimmed = value.trimmingCharacters(in: .whitespacesAndNewlines)
lanHost = trimmed.isEmpty ? nil : trimmed
}
if let value = txt["tailnetDns"] {
let trimmed = value.trimmingCharacters(in: .whitespacesAndNewlines)
tailnetDns = trimmed.isEmpty ? nil : trimmed
}
if let value = txt["sshPort"],
let parsed = Int(value.trimmingCharacters(in: .whitespacesAndNewlines)),
parsed > 0
{
sshPort = parsed
}
if let value = txt["gatewayPort"],
let parsed = Int(value.trimmingCharacters(in: .whitespacesAndNewlines)),
parsed > 0
{
gatewayPort = parsed
}
if let value = txt["cliPath"] {
let trimmed = value.trimmingCharacters(in: .whitespacesAndNewlines)
cliPath = trimmed.isEmpty ? nil : trimmed
}
return GatewayTXT(
lanHost: lanHost,
tailnetDns: tailnetDns,
sshPort: sshPort,
gatewayPort: gatewayPort,
cliPath: cliPath)
}
public static func buildSSHTarget(user: String, host: String, port: Int) -> String {
var target = "\(user)@\(host)"
if port != 22 {
target += ":\(port)"
}
return target
}
private func ensureTXTResolution(
stableID: String,
serviceName: String,
type: String,
domain: String)
{
guard self.resolvedTXTByID[stableID] == nil else { return }
guard self.pendingTXTResolvers[stableID] == nil else { return }
let resolver = GatewayTXTResolver(
name: serviceName,
type: type,
domain: domain,
logger: self.logger)
{ [weak self] result in
Task { @MainActor in
guard let self else { return }
self.pendingTXTResolvers[stableID] = nil
switch result {
case let .success(txt):
self.resolvedTXTByID[stableID] = txt
self.updateGatewaysForAllDomains()
self.recomputeGateways()
case .failure:
break
}
}
}
self.pendingTXTResolvers[stableID] = resolver
resolver.start()
}
private nonisolated static func prettifyInstanceName(_ decodedName: String) -> String {
let normalized = decodedName.split(whereSeparator: \.isWhitespace).joined(separator: " ")
let stripped = normalized.replacingOccurrences(of: " (Clawdbot)", with: "")
.replacingOccurrences(of: #"\s+\(\d+\)$"#, with: "", options: .regularExpression)
return stripped.trimmingCharacters(in: .whitespacesAndNewlines)
}
private nonisolated static func prettifyServiceName(_ decodedName: String) -> String {
let normalized = Self.prettifyInstanceName(decodedName)
var cleaned = normalized.replacingOccurrences(of: #"\s*-?bridge$"#, with: "", options: .regularExpression)
cleaned = cleaned
.replacingOccurrences(of: "_", with: " ")
.replacingOccurrences(of: "-", with: " ")
.replacingOccurrences(of: #"\s+"#, with: " ", options: .regularExpression)
.trimmingCharacters(in: .whitespacesAndNewlines)
if cleaned.isEmpty {
cleaned = normalized
}
let words = cleaned.split(separator: " ")
let titled = words.map { word -> String in
let lower = word.lowercased()
guard let first = lower.first else { return "" }
return String(first).uppercased() + lower.dropFirst()
}.joined(separator: " ")
return titled.isEmpty ? normalized : titled
}
public nonisolated static func isLocalGateway(
lanHost: String?,
tailnetDns: String?,
displayName: String?,
serviceName: String?,
local: LocalIdentity) -> Bool
{
if let host = normalizeHostToken(lanHost),
local.hostTokens.contains(host)
{
return true
}
if let host = normalizeHostToken(tailnetDns),
local.hostTokens.contains(host)
{
return true
}
if let name = normalizeDisplayToken(displayName),
local.displayTokens.contains(name)
{
return true
}
if let service = normalizeServiceToken(serviceName) {
for token in local.hostTokens where service.contains(token) {
return true
}
}
return false
}
private func refreshLocalIdentity() {
let fastIdentity = self.localIdentity
let displayName = self.localDisplayName
Task.detached(priority: .utility) {
let slowIdentity = Self.buildLocalIdentitySlow(displayName: displayName)
let merged = Self.mergeLocalIdentity(fast: fastIdentity, slow: slowIdentity)
await MainActor.run { [weak self] in
guard let self else { return }
guard self.localIdentity != merged else { return }
self.localIdentity = merged
self.recomputeGateways()
}
}
}
private nonisolated static func mergeLocalIdentity(
fast: LocalIdentity,
slow: LocalIdentity) -> LocalIdentity
{
LocalIdentity(
hostTokens: fast.hostTokens.union(slow.hostTokens),
displayTokens: fast.displayTokens.union(slow.displayTokens))
}
private nonisolated static func buildLocalIdentityFast(displayName: String?) -> LocalIdentity {
var hostTokens: Set<String> = []
var displayTokens: Set<String> = []
let hostName = ProcessInfo.processInfo.hostName
if let token = normalizeHostToken(hostName) {
hostTokens.insert(token)
}
if let token = normalizeDisplayToken(displayName) {
displayTokens.insert(token)
}
return LocalIdentity(hostTokens: hostTokens, displayTokens: displayTokens)
}
private nonisolated static func buildLocalIdentitySlow(displayName: String?) -> LocalIdentity {
var hostTokens: Set<String> = []
var displayTokens: Set<String> = []
if let host = Host.current().name,
let token = normalizeHostToken(host)
{
hostTokens.insert(token)
}
if let token = normalizeDisplayToken(displayName) {
displayTokens.insert(token)
}
if let token = normalizeDisplayToken(Host.current().localizedName) {
displayTokens.insert(token)
}
return LocalIdentity(hostTokens: hostTokens, displayTokens: displayTokens)
}
private nonisolated static func normalizeHostToken(_ raw: String?) -> String? {
guard let raw else { return nil }
let trimmed = raw.trimmingCharacters(in: .whitespacesAndNewlines)
if trimmed.isEmpty { return nil }
let lower = trimmed.lowercased()
let strippedTrailingDot = lower.hasSuffix(".")
? String(lower.dropLast())
: lower
let withoutLocal = strippedTrailingDot.hasSuffix(".local")
? String(strippedTrailingDot.dropLast(6))
: strippedTrailingDot
let firstLabel = withoutLocal.split(separator: ".").first.map(String.init)
let token = (firstLabel ?? withoutLocal).trimmingCharacters(in: .whitespacesAndNewlines)
return token.isEmpty ? nil : token
}
private nonisolated static func normalizeDisplayToken(_ raw: String?) -> String? {
guard let raw else { return nil }
let prettified = Self.prettifyInstanceName(raw)
let trimmed = prettified.trimmingCharacters(in: .whitespacesAndNewlines)
if trimmed.isEmpty { return nil }
return trimmed.lowercased()
}
private nonisolated static func normalizeServiceToken(_ raw: String?) -> String? {
guard let raw else { return nil }
let trimmed = raw.trimmingCharacters(in: .whitespacesAndNewlines)
if trimmed.isEmpty { return nil }
return trimmed.lowercased()
}
}
final class GatewayTXTResolver: NSObject, NetServiceDelegate {
private let service: NetService
private let completion: (Result<[String: String], Error>) -> Void
private let logger: Logger
private var didFinish = false
init(
name: String,
type: String,
domain: String,
logger: Logger,
completion: @escaping (Result<[String: String], Error>) -> Void)
{
self.service = NetService(domain: domain, type: type, name: name)
self.completion = completion
self.logger = logger
super.init()
self.service.delegate = self
}
func start(timeout: TimeInterval = 2.0) {
self.service.schedule(in: .main, forMode: .common)
self.service.resolve(withTimeout: timeout)
}
func cancel() {
self.finish(result: .failure(GatewayTXTResolverError.cancelled))
}
func netServiceDidResolveAddress(_ sender: NetService) {
let txt = Self.decodeTXT(sender.txtRecordData())
if !txt.isEmpty {
let payload = self.formatTXT(txt)
self.logger.debug(
"discovery: resolved TXT for \(sender.name, privacy: .public): \(payload, privacy: .public)")
}
self.finish(result: .success(txt))
}
func netService(_ sender: NetService, didNotResolve errorDict: [String: NSNumber]) {
self.finish(result: .failure(GatewayTXTResolverError.resolveFailed(errorDict)))
}
private func finish(result: Result<[String: String], Error>) {
guard !self.didFinish else { return }
self.didFinish = true
self.service.stop()
self.service.remove(from: .main, forMode: .common)
self.completion(result)
}
private static func decodeTXT(_ data: Data?) -> [String: String] {
guard let data else { return [:] }
let dict = NetService.dictionary(fromTXTRecord: data)
var out: [String: String] = [:]
out.reserveCapacity(dict.count)
for (key, value) in dict {
if let str = String(data: value, encoding: .utf8) {
out[key] = str
}
}
return out
}
private func formatTXT(_ txt: [String: String]) -> String {
txt.sorted(by: { $0.key < $1.key })
.map { "\($0.key)=\($0.value)" }
.joined(separator: " ")
}
}
enum GatewayTXTResolverError: Error {
case cancelled
case resolveFailed([String: NSNumber])
}

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import ClawdbotKit
import Foundation
struct WideAreaGatewayBeacon: Sendable, Equatable {
var instanceName: String
var displayName: String
var host: String
var port: Int
var lanHost: String?
var tailnetDns: String?
var gatewayPort: Int?
var bridgePort: Int?
var sshPort: Int?
var cliPath: String?
}
enum WideAreaGatewayDiscovery {
private static let maxCandidates = 40
private static let digPath = "/usr/bin/dig"
private static let defaultTimeoutSeconds: TimeInterval = 0.2
struct DiscoveryContext: Sendable {
var tailscaleStatus: @Sendable () -> String?
var dig: @Sendable (_ args: [String], _ timeout: TimeInterval) -> String?
static let live = DiscoveryContext(
tailscaleStatus: { readTailscaleStatus() },
dig: { args, timeout in
runDig(args: args, timeout: timeout)
})
}
static func discover(
timeoutSeconds: TimeInterval = 2.0,
context: DiscoveryContext = .live) -> [WideAreaGatewayBeacon]
{
let startedAt = Date()
let remaining = {
timeoutSeconds - Date().timeIntervalSince(startedAt)
}
guard let ips = collectTailnetIPv4s(
statusJson: context.tailscaleStatus()).nonEmpty else { return [] }
var candidates = Array(ips.prefix(self.maxCandidates))
guard let nameserver = findNameserver(
candidates: &candidates,
remaining: remaining,
dig: context.dig)
else {
return []
}
let domain = ClawdbotBonjour.wideAreaBridgeServiceDomain
let domainTrimmed = domain.trimmingCharacters(in: CharacterSet(charactersIn: "."))
let probeName = "_clawdbot-bridge._tcp.\(domainTrimmed)"
guard let ptrLines = context.dig(
["+short", "+time=1", "+tries=1", "@\(nameserver)", probeName, "PTR"],
min(defaultTimeoutSeconds, remaining()))?.split(whereSeparator: \.isNewline),
!ptrLines.isEmpty
else {
return []
}
var beacons: [WideAreaGatewayBeacon] = []
for raw in ptrLines {
let ptr = raw.trimmingCharacters(in: .whitespacesAndNewlines)
if ptr.isEmpty { continue }
let ptrName = ptr.hasSuffix(".") ? String(ptr.dropLast()) : ptr
let suffix = "._clawdbot-bridge._tcp.\(domainTrimmed)"
let rawInstanceName = ptrName.hasSuffix(suffix)
? String(ptrName.dropLast(suffix.count))
: ptrName
let instanceName = self.decodeDnsSdEscapes(rawInstanceName)
guard let srv = context.dig(
["+short", "+time=1", "+tries=1", "@\(nameserver)", ptrName, "SRV"],
min(defaultTimeoutSeconds, remaining()))
else { continue }
guard let (host, port) = parseSrv(srv) else { continue }
let txtRaw = context.dig(
["+short", "+time=1", "+tries=1", "@\(nameserver)", ptrName, "TXT"],
min(self.defaultTimeoutSeconds, remaining()))
let txtTokens = txtRaw.map(self.parseTxtTokens) ?? []
let txt = self.mapTxt(tokens: txtTokens)
let displayName = txt["displayName"] ?? instanceName
let beacon = WideAreaGatewayBeacon(
instanceName: instanceName,
displayName: displayName,
host: host,
port: port,
lanHost: txt["lanHost"],
tailnetDns: txt["tailnetDns"],
gatewayPort: parseInt(txt["gatewayPort"]),
bridgePort: parseInt(txt["bridgePort"]),
sshPort: parseInt(txt["sshPort"]),
cliPath: txt["cliPath"])
beacons.append(beacon)
}
return beacons
}
private static func collectTailnetIPv4s(statusJson: String?) -> [String] {
guard let statusJson else { return [] }
let decoder = JSONDecoder()
guard let data = statusJson.data(using: .utf8),
let status = try? decoder.decode(TailscaleStatus.self, from: data)
else { return [] }
var ips: [String] = []
ips.append(contentsOf: status.selfNode?.resolvedIPs ?? [])
if let peers = status.peer {
for peer in peers.values {
ips.append(contentsOf: peer.resolvedIPs)
}
}
var seen = Set<String>()
let ordered = ips.filter { value in
guard self.isTailnetIPv4(value) else { return false }
if seen.contains(value) { return false }
seen.insert(value)
return true
}
return ordered
}
private static func readTailscaleStatus() -> String? {
let candidates = [
"/usr/local/bin/tailscale",
"/opt/homebrew/bin/tailscale",
"/Applications/Tailscale.app/Contents/MacOS/Tailscale",
"tailscale",
]
var output: String?
for candidate in candidates {
if let result = run(
path: candidate,
args: ["status", "--json"],
timeout: 0.7)
{
output = result
break
}
}
return output
}
private static func findNameserver(
candidates: inout [String],
remaining: () -> TimeInterval,
dig: @Sendable (_ args: [String], _ timeout: TimeInterval) -> String?) -> String?
{
let domain = ClawdbotBonjour.wideAreaBridgeServiceDomain
let domainTrimmed = domain.trimmingCharacters(in: CharacterSet(charactersIn: "."))
let probeName = "_clawdbot-bridge._tcp.\(domainTrimmed)"
while !candidates.isEmpty {
if remaining() <= 0 { break }
let ip = candidates.removeFirst()
if let stdout = dig(
["+short", "+time=1", "+tries=1", "@\(ip)", probeName, "PTR"],
min(defaultTimeoutSeconds, remaining())),
stdout.split(whereSeparator: \.isNewline).isEmpty == false
{
return ip
}
}
return nil
}
private static func runDig(args: [String], timeout: TimeInterval) -> String? {
self.run(path: self.digPath, args: args, timeout: timeout)
}
private static func run(path: String, args: [String], timeout: TimeInterval) -> String? {
let process = Process()
process.executableURL = URL(fileURLWithPath: path)
process.arguments = args
let outPipe = Pipe()
let errPipe = Pipe()
process.standardOutput = outPipe
process.standardError = errPipe
do {
try process.run()
} catch {
return nil
}
let deadline = Date().addingTimeInterval(timeout)
while process.isRunning, Date() < deadline {
Thread.sleep(forTimeInterval: 0.02)
}
if process.isRunning {
process.terminate()
}
process.waitUntilExit()
let data = outPipe.fileHandleForReading.readDataToEndOfFile()
let output = String(data: data, encoding: .utf8)?.trimmingCharacters(in: .whitespacesAndNewlines)
return output?.isEmpty == false ? output : nil
}
private static func parseSrv(_ stdout: String) -> (String, Int)? {
let line = stdout
.split(whereSeparator: \.isNewline)
.map { $0.trimmingCharacters(in: .whitespacesAndNewlines) }
.first(where: { !$0.isEmpty })
guard let line else { return nil }
let parts = line.split(whereSeparator: { $0 == " " || $0 == "\t" }).map(String.init)
guard parts.count >= 4 else { return nil }
guard let port = Int(parts[2]), port > 0 else { return nil }
let host = parts[3].hasSuffix(".") ? String(parts[3].dropLast()) : parts[3]
return (host, port)
}
private static func parseTxtTokens(_ stdout: String) -> [String] {
let lines = stdout.split(whereSeparator: \.isNewline)
var tokens: [String] = []
for raw in lines {
let line = raw.trimmingCharacters(in: .whitespacesAndNewlines)
if line.isEmpty { continue }
let matches = line.matches(of: /"([^"]*)"/)
for match in matches {
tokens.append(self.unescapeTxt(String(match.1)))
}
}
return tokens
}
private static func unescapeTxt(_ value: String) -> String {
value
.replacingOccurrences(of: "\\\\", with: "\\")
.replacingOccurrences(of: "\\\"", with: "\"")
.replacingOccurrences(of: "\\n", with: "\n")
}
private static func mapTxt(tokens: [String]) -> [String: String] {
var out: [String: String] = [:]
for token in tokens {
guard let idx = token.firstIndex(of: "=") else { continue }
let key = String(token[..<idx]).trimmingCharacters(in: .whitespacesAndNewlines)
let rawValue = String(token[token.index(after: idx)...])
.trimmingCharacters(in: .whitespacesAndNewlines)
let value = self.decodeDnsSdEscapes(rawValue)
if !key.isEmpty { out[key] = value }
}
return out
}
private static func parseInt(_ value: String?) -> Int? {
guard let value else { return nil }
let trimmed = value.trimmingCharacters(in: .whitespacesAndNewlines)
return Int(trimmed)
}
private static func isTailnetIPv4(_ value: String) -> Bool {
let parts = value.split(separator: ".")
if parts.count != 4 { return false }
let octets = parts.compactMap { Int($0) }
if octets.count != 4 { return false }
let a = octets[0]
let b = octets[1]
return a == 100 && b >= 64 && b <= 127
}
private static func decodeDnsSdEscapes(_ value: String) -> String {
var bytes: [UInt8] = []
var pending = ""
func flushPending() {
guard !pending.isEmpty else { return }
bytes.append(contentsOf: pending.utf8)
pending = ""
}
let chars = Array(value)
var i = 0
while i < chars.count {
let ch = chars[i]
if ch == "\\", i + 3 < chars.count {
let digits = String(chars[(i + 1)...(i + 3)])
if digits.allSatisfy(\.isNumber),
let byte = UInt8(digits)
{
flushPending()
bytes.append(byte)
i += 4
continue
}
}
pending.append(ch)
i += 1
}
flushPending()
if bytes.isEmpty { return value }
if let decoded = String(bytes: bytes, encoding: .utf8) {
return decoded
}
return value
}
}
private struct TailscaleStatus: Decodable {
struct Node: Decodable {
let tailscaleIPs: [String]?
var resolvedIPs: [String] {
self.tailscaleIPs ?? []
}
private enum CodingKeys: String, CodingKey {
case tailscaleIPs = "TailscaleIPs"
}
}
let selfNode: Node?
let peer: [String: Node]?
private enum CodingKeys: String, CodingKey {
case selfNode = "Self"
case peer = "Peer"
}
}
extension Collection {
fileprivate var nonEmpty: Self? { isEmpty ? nil : self }
}