feat(pairing): seamless no-PIN delegated approval (host parks the knock, clients add "Request access")

Web-console "Approve" (delegated pairing, roadmap §8b-1) was unreachable: every client routed a fresh pair=required host straight to the SPAKE2 PIN ceremony, so no "knock" was ever recorded; and an unpaired connect was rejected+closed with no way to resume after approval. The backend + console were complete but had no client-side trigger and no post-approval admit path. Host (native_pairing.rs, punktfunk1.rs): an unpaired identified knock is now PARKED instead of rejected — it releases its NVENC session permit, awaits an operator decision (NativePairing::wait_for_decision, woken by a Notify on approve/deny), and on approval re-acquires a slot and admits the SAME connection with no reconnect. QUIC keep-alive (4s/8s) holds the parked connection warm. The pairing gate moves out of the HANDSHAKE_TIMEOUT-bounded handshake future; approve_pending is reordered read-then-add and wait_for_decision double-checks is_paired to close a "neither pending nor paired" race. New PENDING_APPROVAL_WAIT (180s). Tests: delegated_approval_admits_after_knock now approves mid-park (no reconnect) + new wait_for_decision_approve_deny_timeout unit test (108 host tests green). Clients (Linux/Apple/Windows/Android): a fresh pair=required host now offers "Request access" alongside the PIN ceremony — a plain identified connect with a ~185s handshake budget and a cancelable "waiting for approval" UI; on success the host is saved as paired, and cancel returns the UI immediately while a late- resolving connect is torn down silently via a per-attempt flag. Apple reuses the existing C-ABI timeout_ms (no ABI change); Windows adds SessionParams.connect_timeout + a RequestAccess screen; Android adds a timeoutMs arg to the nativeConnect JNI seam (both sides + both callers). Linux built + clippy + fmt clean; Apple/Windows/ Android pending their CI/on-device compiles. SPAKE2 ceremony reviewed end-to-end against the spake2 0.4 contract — correct, no changes needed. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-29 06:41:09 +00:00
parent 705a8fa94e
commit d1d2ca293d
13 changed files with 1149 additions and 161 deletions
@@ -74,10 +74,31 @@ import io.unom.punktfunk.kit.security.KnownHostStore
 import io.unom.punktfunk.kit.security.obtainIdentity
 import io.unom.punktfunk.models.HostStatus
 import io.unom.punktfunk.models.PendingTrust
+import java.util.concurrent.atomic.AtomicBoolean
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext

+/** Handshake budget for a normal connect (the prior hardcoded value, now passed explicitly). */
+private const val CONNECT_TIMEOUT_MS = 10_000
+
+/**
+ * Handshake budget for the no-PIN "request access" connect. Must exceed the host's approval-park
+ * window (~180 s) so a slow operator approval still lands on this same parked connection rather than
+ * timing the client out first. Mirrors the Linux client's 185 s.
+ */
+private const val REQUEST_ACCESS_TIMEOUT_MS = 185_000
+
+/**
+ * A no-PIN "request access" connect in flight — the host being requested (drives the cancelable
+ * "Waiting for approval…" dialog) and a per-attempt flag the Cancel button trips. The connect is a
+ * blocking call with no abort, so Cancel returns the UI immediately and a late result checks
+ * [cancelled] and tears the (possibly just-approved) session down silently rather than navigating.
+ */
+private class RequestAccessState(val target: PendingTrust) {
+    val cancelled = AtomicBoolean(false)
+}
+
@OptIn(ExperimentalMaterial3Api::class)
@Composable
 fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
@@ -128,8 +149,11 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
            .onSuccess { identity = it }
            .onFailure { status = "Identity unavailable: ${it.message} — re-pair may be required" }
    }
-    // A trust decision awaiting the user (first-connect TOFU / fp changed / PIN pairing).
+    // A trust decision awaiting the user (first-connect TOFU / fp changed / PIN pairing / the
+    // request-access-or-PIN choice).
    var pendingTrust by remember { mutableStateOf<PendingTrust?>(null) }
+    // A no-PIN "request access" connect in flight (the cancelable "Waiting for approval…" dialog).
+    var awaiting by remember { mutableStateOf<RequestAccessState?>(null) }
    // A saved host whose label is being edited (the Rename dialog).
    var renameTarget by remember { mutableStateOf<KnownHost?>(null) }

@@ -163,7 +187,7 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
                    targetHost, targetPort, w, h, hz,
                    id.certPem, id.privateKeyPem, pinHex ?: "",
                    settings.bitrateKbps, settings.compositor, gamepadPref,
-                    hdrEnabled, settings.audioChannels,
+                    hdrEnabled, settings.audioChannels, CONNECT_TIMEOUT_MS,
                )
            }
            connecting = false
@@ -182,10 +206,66 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
        }
    }

-    // Decide pinned-reconnect vs fp-changed vs TOFU vs PIN pairing before connecting. Trust state is
+    // The no-PIN "request access" path (delegated approval): open a normal identified connect that
+    // the host PARKS until the operator clicks Approve in its console/web UI, showing a cancelable
+    // "Waiting for approval…" dialog meanwhile. The SAME connection is admitted on approval (no
+    // reconnect), so on success we record the host as PAIRED — the operator's approval IS the pairing.
+    // The connect can't be aborted, so Cancel returns the UI immediately and a late result is torn
+    // down silently via the per-attempt flag (mirrors the Linux client's request-access flow).
+    fun requestAccess(target: PendingTrust) {
+        val id = identity
+        if (id == null) {
+            status = "Identity not ready yet — try again in a moment"
+            return
+        }
+        val req = RequestAccessState(target)
+        awaiting = req
+        connecting = true
+        status = null
+        discovery.stop() // free the Wi-Fi radio before the (parked) stream session
+        scope.launch {
+            val hdrEnabled = displaySupportsHdr(context)
+            val gamepadPref = Gamepad.resolvePref(settings.gamepad)
+            // Pin the advertised fingerprint for a discovered host (defence against an impostor while
+            // we wait); a manually-typed host has none, so trust-on-first-use.
+            val pinHex = target.advertisedFp ?: ""
+            val handle = withContext(Dispatchers.IO) {
+                NativeBridge.nativeConnect(
+                    target.host, target.port, w, h, hz,
+                    id.certPem, id.privateKeyPem, pinHex,
+                    settings.bitrateKbps, settings.compositor, gamepadPref,
+                    hdrEnabled, settings.audioChannels, REQUEST_ACCESS_TIMEOUT_MS,
+                )
+            }
+            // Cancelled while we were parked: tear the (possibly just-approved) session down and
+            // don't touch UI a fresh action may now own.
+            if (req.cancelled.get()) {
+                if (handle != 0L) withContext(Dispatchers.IO) { NativeBridge.nativeClose(handle) }
+                return@launch
+            }
+            awaiting = null
+            connecting = false
+            if (handle != 0L) {
+                // Approved — save the host as PAIRED, pinning the fingerprint it presented, so
+                // future connects are silent (exactly like after a PIN ceremony).
+                val fp = NativeBridge.nativeHostFingerprint(handle)
+                if (fp.isNotEmpty()) {
+                    knownHostStore.save(KnownHost(target.host, target.port, target.name, fp, paired = true))
+                    savedHosts = knownHostStore.all()
+                }
+                onConnected(handle)
+            } else {
+                status = "Request timed out — approve this device in the host's console, then retry."
+                discovery.start()
+            }
+        }
+    }
+
+    // Decide pinned-reconnect vs fp-changed vs TOFU vs pairing before connecting. Trust state is
    // keyed by address:port, so a discovered and a manually-typed connection to the same host share
    // one record. Trust-on-first-use is permitted ONLY when the host advertised pair=optional; a
-    // pair=required host, or a manual/unknown-policy host, must pair by PIN.
+    // pair=required host, or a manual/unknown-policy host, must pair — either by no-PIN request
+    // access (approve in the console) or by the SPAKE2 PIN ceremony.
    fun connect(
        targetHost: String,
        targetPort: Int,
@@ -208,9 +288,10 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
            // clearly labeled, alongside PIN pairing). Smart-cast: this branch ⇒ dh != null.
            dh?.pairingRequired == false -> pendingTrust =
                PendingTrust(targetHost, targetPort, name, dh.fingerprint, PendingTrust.Kind.TRUST_NEW)
-            // pair=required, or a manual/unknown-policy host → PIN pairing is mandatory.
+            // pair=required, or a manual/unknown-policy host → offer the two ways in: a no-PIN
+            // "request access" (approve in the console) or the SPAKE2 PIN ceremony.
            else -> pendingTrust =
-                PendingTrust(targetHost, targetPort, name, adv, PendingTrust.Kind.PAIR)
+                PendingTrust(targetHost, targetPort, name, adv, PendingTrust.Kind.REQUEST_ACCESS)
        }
    }

@@ -471,6 +552,33 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
                    TextButton({ pendingTrust = null }) { Text("Cancel") }
                },
            )
+            // A fresh pair=required (or manual/unknown-policy) host: offer the two ways in. "Request
+            // access" is the no-PIN path — connect and wait for the operator to click Approve in the
+            // host's console; "Use a PIN…" switches to the SPAKE2 ceremony.
+            PendingTrust.Kind.REQUEST_ACCESS -> AlertDialog(
+                onDismissRequest = { pendingTrust = null },
+                title = { Text("Pairing required") },
+                text = {
+                    Column {
+                        Text("${pt.host}:${pt.port} requires pairing before it will stream.")
+                        Text(
+                            "Request access and approve this device in the host's console (or web " +
+                                "UI) — no PIN needed. Or pair with the 4-digit PIN the host displays.",
+                        )
+                    }
+                },
+                confirmButton = {
+                    TextButton({ pendingTrust = null; requestAccess(pt) }) { Text("Request access") }
+                },
+                dismissButton = {
+                    Row {
+                        TextButton({ pendingTrust = pt.copy(kind = PendingTrust.Kind.PAIR) }) {
+                            Text("Use a PIN…")
+                        }
+                        TextButton({ pendingTrust = null }) { Text("Cancel") }
+                    }
+                },
+            )
            PendingTrust.Kind.PAIR -> {
                var pin by remember(pt) { mutableStateOf("") }
                var name by remember(pt) { mutableStateOf(Build.MODEL ?: "Android") }
@@ -537,6 +645,44 @@ fun ConnectScreen(settings: Settings, onConnected: (Long) -> Unit) {
        }
    }

+    // The no-PIN "request access" wait: the connect is parked on the host until the operator
+    // approves this device. Cancel returns the UI immediately — it trips the per-attempt flag so a
+    // late approval is torn down silently (see requestAccess) and resumes discovery.
+    awaiting?.let { req ->
+        fun cancel() {
+            req.cancelled.set(true)
+            awaiting = null
+            connecting = false
+            discovery.start() // the request may still be pending on the host; keep scanning
+        }
+        AlertDialog(
+            onDismissRequest = { cancel() },
+            title = { Text("Waiting for approval") },
+            text = {
+                val deviceName = Build.MODEL ?: "this device"
+                Column(verticalArrangement = Arrangement.spacedBy(12.dp)) {
+                    Row(
+                        verticalAlignment = Alignment.CenterVertically,
+                        horizontalArrangement = Arrangement.spacedBy(12.dp),
+                    ) {
+                        CircularProgressIndicator(modifier = Modifier.size(20.dp), strokeWidth = 2.dp)
+                        Text("Approve this device on ${req.target.name}.")
+                    }
+                    Text(
+                        "Open the host's console (or web UI) and approve “$deviceName”. It connects " +
+                            "automatically once you approve — no PIN needed.",
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    )
+                }
+            },
+            confirmButton = {},
+            dismissButton = {
+                TextButton(onClick = { cancel() }) { Text("Cancel") }
+            },
+        )
+    }
+
    // Rename a saved host's label (discovered hosts are named by mDNS; this is how you give one a
    // friendly name like "Living Room" after pairing). Keyed by the host so reopening resets the field.
    renameTarget?.let { kh ->
@@ -14,8 +14,10 @@ enum class Tab(val label: String, val icon: ImageVector) {
 /**
 * A trust decision awaiting the user before a connect proceeds. [name] is the label to save the
 * host under. Trust-on-first-use ([Kind.TRUST_NEW]) is only ever offered when the host ADVERTISED
- * pair=optional; a pair=required host or a manually-typed/unknown-policy host goes straight to PIN
- * pairing ([Kind.PAIR]), and a changed fingerprint forces re-pairing — never a silent re-trust.
+ * pair=optional; a pair=required host or a manually-typed/unknown-policy host is offered the
+ * two ways in ([Kind.REQUEST_ACCESS]): a no-PIN "request access" connect the operator approves in
+ * the host's console, or the SPAKE2 PIN ceremony ([Kind.PAIR]). A changed fingerprint forces
+ * re-pairing by PIN ([Kind.FP_CHANGED]) — never a silent re-trust.
 */
 data class PendingTrust(
    val host: String,
@@ -24,7 +26,7 @@ data class PendingTrust(
    val advertisedFp: String?,
    val kind: Kind,
 ) {
-    enum class Kind { TRUST_NEW, FP_CHANGED, PAIR }
+    enum class Kind { TRUST_NEW, FP_CHANGED, PAIR, REQUEST_ACCESS }
 }

 /** Trust state of a host, shown as a colored pill on its card. */
@@ -29,8 +29,10 @@ object NativeBridge {
     * trust-on-first-use — read [nativeHostFingerprint] after; else 64-hex host SHA-256, mismatch →
     * `0`). [width]/[height]/[refreshHz] are the requested virtual-output mode (the host streams at
     * exactly this); [bitrateKbps] 0 = host default; [compositorPref]/[gamepadPref] are the
-     * `CompositorPref`/`GamepadPref` wire bytes (0 = Auto). Returns an opaque session handle, or `0`
-     * on failure. Pair with exactly one [nativeClose].
+     * `CompositorPref`/`GamepadPref` wire bytes (0 = Auto). [timeoutMs] is the handshake budget — the
+     * normal path passes a short value, the no-PIN "request access" path a long one (≥ the host's
+     * approval-park window) so a slow operator approval lands on this same parked connection. Returns
+     * an opaque session handle, or `0` on failure. Pair with exactly one [nativeClose].
     */
    external fun nativeConnect(
        host: String,
@@ -46,6 +48,7 @@ object NativeBridge {
        gamepadPref: Int,
        hdrEnabled: Boolean,
        audioChannels: Int,
+        timeoutMs: Int,
    ): Long

    /** 64-hex SHA-256 of the cert the host presented on [handle]; valid after a successful connect. */
@@ -140,13 +140,15 @@ pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeGenerateIde
 }

 /// `NativeBridge.nativeConnect(host, port, w, h, hz, certPem, keyPem, pinHex, bitrateKbps,
-/// compositorPref, gamepadPref, hdrEnabled, audioChannels): Long`. `certPem`/`keyPem` empty =
-/// anonymous, else presented as the persistent identity. `pinHex` empty = TOFU (read
+/// compositorPref, gamepadPref, hdrEnabled, audioChannels, timeoutMs): Long`. `certPem`/`keyPem`
+/// empty = anonymous, else presented as the persistent identity. `pinHex` empty = TOFU (read
 /// `nativeHostFingerprint` after), else 64-hex SHA-256 to pin the host (mismatch → 0). `bitrateKbps`
 /// 0 = host default. `compositorPref`/`gamepadPref` are `CompositorPref`/`GamepadPref` wire bytes
 /// (0 = Auto; unknown → Auto). `audioChannels` is the requested surround layout (2/6/8; normalized,
-/// anything else → stereo) — the host clamps it and the resolved count drives playback.
-/// Returns an opaque handle, or 0 on failure (logged).
+/// anything else → stereo) — the host clamps it and the resolved count drives playback. `timeoutMs`
+/// is the handshake budget: the normal path passes a short value, the no-PIN "request access" path a
+/// long one (≥ the host's approval-park window) so a slow operator approval lands on this same parked
+/// connection rather than timing the client out first. Returns an opaque handle, or 0 on failure.
 #[no_mangle]
 #[allow(clippy::too_many_arguments)]
 pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeConnect<'local>(
@@ -165,6 +167,7 @@ pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeConnect<'lo
    gamepad_pref: jint,
    hdr_enabled: jboolean,
    audio_channels: jint,
+    timeout_ms: jint,
 ) -> jlong {
    let host: String = match env.get_string(&host) {
        Ok(s) => s.into(),
@@ -224,7 +227,9 @@ pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeConnect<'lo
        None,     // launch: default app
        pin,      // Some → Crypto on host-fp mismatch
        identity, // owned (cert, key) PEM, or None (anonymous)
-        Duration::from_secs(10),
+        // Handshake budget from Kotlin: ~10 s for a normal connect, ~185 s for "request access"
+        // (the host parks the connection until the operator approves the device — see ConnectScreen).
+        Duration::from_millis(timeout_ms.max(0) as u64),
    ) {
        Ok(client) => {
            let handle = SessionHandle {