Harden direct auth path and regression helper

PHASE5_RUNBOOK.md

@@ -203,4 +203,18 @@ Verified result on 2026-04-25:
   - `/dev/hidraw0` and `/dev/hidraw1` are visible in `k_proxy` again
   - `/dev/hidraw0` opens successfully as the normal user, but `/dev/hidraw1` is still permission-denied
   - raw `makeCredential` still shows no card prompt, so the hang is before the firmware confirmation UI
-  - next step is to identify which hidraw interface `python-fido2` is selecting
+  - hidraw inspection confirms `/dev/hidraw0` is the real FIDO interface and `/dev/hidraw1` is a separate vendor HID interface
+  - manual CTAPHID `INIT` written directly to `/dev/hidraw0` gets no reply at all within `3s`
+  - rerunning `webauthn_local_demo.py` inside `k_proxy` also shows no card prompt on register
+  - next step is to recover the USB/Qubes transport path before retrying direct auth
+  - after a full power cycle and reattach, manual CTAPHID `INIT` replies again and `webauthn_local_demo.py` registration succeeds again
+  - direct `raw_ctap_probe.py --device-path /dev/hidraw0 make-credential --rp-id localhost` also succeeds again after pressing `yes` on the card
+  - `k_proxy_app.py --auth-mode fido2-direct` was patched to use low-level CTAP2 and explicit `/dev/hidraw0`
+  - after additional fixes for hidraw lifetime, VM-side `python-fido2` response mapping, and CTAP payload shape, `/enroll/register` now succeeds again for `directtest`
+  - `/session/login` for `directtest` now also succeeds after card confirmation and returns `auth_mode: "fido2_assertion"`
+  - `/session/status` succeeds
+  - protected `/resource/counter` succeeds again through `k_proxy -> k_server`
+  - `/session/logout` succeeds
+  - post-logout protected access returns `401`
+  - temporary direct-mode hidraw lifetime logging was removed again after diagnosis
+  - `phase5_chain_regression.sh` now supports card-interactive direct auth via `--interactive-card --expect-auth-mode fido2_assertion`

Setup.md

@@ -544,6 +544,42 @@ Session note (2026-04-25, direct FIDO2 auth attempt):
   - direct node-open check confirms `/dev/hidraw0` is readable as the normal user
   - `/dev/hidraw1` still returns `PermissionError: [Errno 13] Permission denied`
   - raw `makeCredential` probe still produced no on-card registration prompt, so the host path is hanging before the firmware Yes/No UI
+  - hidraw mapping confirms `/dev/hidraw0` is the FIDO interface:
+    - report descriptor begins with usage page `0xF1D0`
+    - `get_descriptor('/dev/hidraw0')` returns `report_size_in=64`, `report_size_out=64`
+  - `/dev/hidraw1` is a separate vendor HID interface with usage page `0xFF00`
+  - stale Python probes holding `/dev/hidraw0` were cleared, but behavior did not change
+  - a manual CTAPHID `INIT` packet sent directly to `/dev/hidraw0` writes successfully and still gets no response within `3s`
+  - this places the current blocker below `python-fido2`: raw HID traffic is not getting a CTAPHID reply after the latest reattach
+  - `webauthn_local_demo.py` was re-run inside `k_proxy` after reattach and still produced no card prompt on register
+  - that confirms the current failure is below both the browser WebAuthn path and the direct `python-fido2` path
+  - after a full power cycle and reattach, manual CTAPHID `INIT` on `/dev/hidraw0` started replying again
+  - `webauthn_local_demo.py` register in `k_proxy` then succeeded again, confirming the card transport was recovered by the power cycle
+  - direct host-side registration via `raw_ctap_probe.py --device-path /dev/hidraw0 make-credential --rp-id localhost` also succeeded again after pressing `yes` on the card
+  - returned credential material included:
+    - `fmt="none"`
+    - credential id `7986cfcf45663f625eb7fc7b52640d83cf3d0e8a6627eeadaba3126406b1e0b8`
+  - this confirms the recovered direct path now reaches the real card confirmation UI and completes CTAP2 `makeCredential`
+  - `k_proxy_app.py --auth-mode fido2-direct` was then patched to:
+    - use low-level CTAP2 instead of the higher-level `Fido2Client` registration/assertion calls
+    - open the explicit FIDO node `/dev/hidraw0` instead of scanning devices
+    - cache the direct device handle instead of reopening it for each operation
+  - current remaining blocker:
+    - was narrowed through repeated retries to a mix of hidraw node disappearance, older `python-fido2` response-mapping requirements, and CTAP payload-shape mismatches
+  - latest verified state:
+    - after reattach with healthy CTAPHID `INIT`, real app registration through `k_proxy_app.py --auth-mode fido2-direct` now succeeds
+    - `/enroll/register` for `directtest` returned `ok=true` and `has_credential=true`
+    - real app login through `/session/login` for `directtest` also now succeeds after card confirmation
+    - returned `auth_mode` is `fido2_assertion`
+    - session status succeeds
+    - protected `/resource/counter` access succeeds again through `k_proxy -> k_server`
+    - logout succeeds
+    - post-logout protected access returns `401`
+  - temporary direct-mode hidraw lifetime logging has been removed again after diagnosis
+  - `/home/user/chromecard/phase5_chain_regression.sh` now supports the direct-auth baseline via:
+    - `--interactive-card`
+    - `--login-timeout`
+    - `--expect-auth-mode fido2_assertion`
 - Practical outcome for this session:
   - the experimental direct mode is kept in code for follow-up work
   - the deployed `k_proxy` service was restored to default `probe` mode
@@ -616,7 +652,7 @@ SUBSYSTEM=="hidraw", ATTRS{idVendor}=="1209", ATTRS{idProduct}=="0005", MODE="06
   - `/dev/hidraw*` must exist in `k_proxy`
   - `fido2_probe.py --list` must detect the card before the raw Yes/No probe can continue
 - Identify why the host probe hangs before card UI even with `/dev/hidraw0` readable:
-  - determine which hidraw interface `python-fido2` is selecting on `k_proxy`
+  - determine why CTAPHID `INIT` on the correct FIDO hidraw node receives no reply after reattach
-  - determine whether the blocked path is on the second HID interface or in the Qubes USB mediation layer
+  - likely recovery targets are the Qubes USB mediation path, a fresh USB reassign, or a `k_proxy` VM/device reset
 - Precise ownership split of session/user state between `k_proxy` and `k_server`.
 - Concrete concurrency limits and acceptance criteria (requests/sec, parallel clients, latency/error thresholds).

Workplan.md

@@ -254,6 +254,12 @@ Status (2026-04-25):
   - `/home/user/chromecard/raw_ctap_probe.py` now exists for lower-level CTAP2 probing with keepalive/error logging
   - latest retry result: after reattaching the card, `k_proxy` again exposes `/dev/hidraw0` and `/dev/hidraw1`, but raw `makeCredential` still reaches no Yes/No card prompt
   - `/dev/hidraw0` opens successfully as the normal user; `/dev/hidraw1` is still permission-denied
+  - manual CTAPHID testing now shows `/dev/hidraw0` is the correct FIDO interface and a direct `INIT` write gets no response at all
+  - rerunning `webauthn_local_demo.py` inside `k_proxy` also still gives no card prompt, so the current break is below both browser WebAuthn and direct host probes
+  - after a full power cycle and reattach, manual CTAPHID `INIT` replies again and browser registration in `webauthn_local_demo.py` succeeds again
+  - direct `raw_ctap_probe.py --device-path /dev/hidraw0 make-credential --rp-id localhost` now also succeeds again after card confirmation
+  - `k_proxy_app.py --auth-mode fido2-direct` has been moved onto low-level CTAP2 and explicit `/dev/hidraw0`
+  - after repeated fixes for hidraw lifetime, VM-side `python-fido2` response mapping, and CTAP payload shape, real app registration now succeeds for `directtest`
 
 ## Phase 5.5: Implement Dummy Resource + Access Policy on `k_server`
 
@@ -293,14 +299,18 @@ Status (2026-04-25):
 - Browser traffic goes only to `k_proxy`.
 
 Immediate next action:
-- Determine which hidraw interface the host CTAP stack is actually selecting on `k_proxy`.
+Immediate next action:
-- Verify which interface is blocked:
+- Preserve the now-working direct auth path and record it as the current baseline.
-  - map `/dev/hidraw0` and `/dev/hidraw1` to their USB/HID descriptors
+- Verified end-to-end state:
-  - determine whether `python-fido2` is trying to use the permission-blocked interface
+  - direct `/enroll/register` succeeds for `directtest`
-- Then retry:
+  - direct `/session/login` succeeds for `directtest`
-  - `ssh k_proxy "python3 /home/user/chromecard/raw_ctap_probe.py make-credential --rp-id localhost"`
+  - `/session/status` succeeds
-- Stop before the raw probe and tell the user explicitly to press `yes` or `no` on the card.
+  - protected `/resource/counter` succeeds through `k_proxy -> k_server`
-- Validate end-to-end login to `k_server` resource through proxy chain.
+  - `/session/logout` succeeds
+  - post-logout protected access returns `401`
+- Next work should be cleanup/hardening:
+  - decide whether to keep `directtest` enrollment
+  - rerun `phase5_chain_regression.sh --interactive-card --expect-auth-mode fido2_assertion` against the current direct-auth baseline
 
 Exit criteria:
 - Enrollment and login both function end-to-end via `k_client -> k_proxy -> k_server`.

ctaphid_init_probe.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+"""
+Manual CTAPHID INIT probe for a specific hidraw node.
+
+This bypasses python-fido2's device bootstrap so we can see whether the raw HID
+transport itself exchanges packets on the expected FIDO interface.
+"""
+
+from __future__ import annotations
+
+import argparse
+import os
+import secrets
+import select
+import struct
+import sys
+from pathlib import Path
+
+
+CTAPHID_INIT = 0x06
+TYPE_INIT = 0x80
+BROADCAST_CID = 0xFFFFFFFF
+
+
+def build_init_packet(nonce: bytes) -> bytes:
+    frame = struct.pack(">IBH", BROADCAST_CID, TYPE_INIT | CTAPHID_INIT, len(nonce)) + nonce
+    return b"\0" + frame.ljust(64, b"\0")
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Manual CTAPHID INIT probe")
+    parser.add_argument("--device-path", default="/dev/hidraw0")
+    parser.add_argument("--timeout", type=float, default=3.0)
+    args = parser.parse_args()
+
+    path = Path(args.device_path)
+    if not path.exists():
+        print(f"missing device: {path}", file=sys.stderr)
+        return 2
+
+    nonce = secrets.token_bytes(8)
+    packet = build_init_packet(nonce)
+    print(f"device={path}")
+    print(f"nonce={nonce.hex()}")
+    print(f"write_len={len(packet)}")
+    print(f"write_hex={packet.hex()}")
+
+    fd = os.open(str(path), os.O_RDWR)
+    try:
+        written = os.write(fd, packet)
+        print(f"written={written}")
+        poller = select.poll()
+        poller.register(fd, select.POLLIN)
+        events = poller.poll(int(args.timeout * 1000))
+        print(f"events={events}")
+        if not events:
+            print("timeout_waiting_for_response")
+            return 1
+        response = os.read(fd, 64)
+        print(f"read_len={len(response)}")
+        print(f"read_hex={response.hex()}")
+        if len(response) >= 24:
+            cid, cmd, bc = struct.unpack(">IBH", response[:7])
+            print(f"resp_cid=0x{cid:08x}")
+            print(f"resp_cmd=0x{cmd:02x}")
+            print(f"resp_bc={bc}")
+            print(f"resp_payload={response[7:7+bc].hex()}")
+        return 0
+    finally:
+        os.close(fd)
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

k_proxy_app.py

@@ -34,23 +34,29 @@ from urllib.error import HTTPError, URLError
 from urllib.parse import urlparse
 from urllib.request import Request, urlopen
 
+import fido2.features
 from fido2.client import Fido2Client, UserInteraction, verify_rp_id
+from fido2.ctap2 import Ctap2
 from fido2.hid import CtapHidDevice
+from fido2.hid.linux import get_descriptor, open_connection
 from fido2.server import Fido2Server
 from fido2.webauthn import (
     AttestedCredentialData,
+    AttestationObject,
+    AuthenticatorAssertionResponse,
+    AuthenticatorAttestationResponse,
+    AuthenticationResponse,
+    CollectedClientData,
     PublicKeyCredentialCreationOptions,
     PublicKeyCredentialRequestOptions,
     PublicKeyCredentialRpEntity,
     PublicKeyCredentialUserEntity,
+    RegistrationResponse,
     UserVerificationRequirement,
 )
 
-try:
+if getattr(fido2.features.webauthn_json_mapping, "_enabled", None) is None:
-    from fido2.client import ClientDataCollector, CollectedClientData
+    fido2.features.webauthn_json_mapping.enabled = True
-except ImportError:
-    ClientDataCollector = None
-    CollectedClientData = None
 
 
 HTML = """<!doctype html>
@@ -420,6 +426,46 @@ def b64u_decode(data: str) -> bytes:
     return base64.urlsafe_b64decode((data + pad).encode("ascii"))
 
 
+def direct_ctap_key_params() -> list[dict[str, Any]]:
+    # Match the raw probe's narrower algorithm set. The broader default list from
+    # Fido2Server.register_begin was still hitting post-confirmation I/O errors.
+    return [
+        {"type": "public-key", "alg": -7},
+        {"type": "public-key", "alg": -257},
+    ]
+
+
+def direct_ctap_rp(rp: PublicKeyCredentialRpEntity) -> dict[str, Any]:
+    return {"id": rp.id, "name": rp.name}
+
+
+def direct_ctap_user(user: PublicKeyCredentialUserEntity) -> dict[str, Any]:
+    user_id = user.id
+    if isinstance(user_id, bytes):
+        # Match the raw probe's ASCII user-id shape rather than sending opaque
+        # binary bytes into the card path.
+        user_id = user_id.hex().encode("ascii")
+    return {
+        "id": user_id,
+        "name": user.name,
+        "displayName": user.display_name or user.name,
+    }
+
+
+def direct_ctap_allow_list(
+    creds: list[Any] | None,
+) -> list[dict[str, Any]] | None:
+    if not creds:
+        return None
+    out: list[dict[str, Any]] = []
+    for cred in creds:
+        cred_id = getattr(cred, "id", None)
+        if cred_id is None and isinstance(cred, dict):
+            cred_id = cred.get("id")
+        out.append({"type": "public-key", "id": cred_id})
+    return out
+
+
 def enrollment_payload(enrollment: "Enrollment", *, created: bool | None = None) -> dict[str, Any]:
     payload: dict[str, Any] = {
         "ok": True,
@@ -434,41 +480,6 @@ def enrollment_payload(enrollment: "Enrollment", *, created: bool | None = None)
     return payload
 
 
-if ClientDataCollector is not None and CollectedClientData is not None:
-
-    class ProxyClientDataCollector(ClientDataCollector):
-        def __init__(self, origin: str, rp_id: str):
-            if not verify_rp_id(rp_id, origin):
-                raise ValueError(f"origin {origin!r} is not valid for rp_id {rp_id!r}")
-            self.origin = origin
-            self.rp_id = rp_id
-
-        def collect_client_data(
-            self,
-            options: PublicKeyCredentialCreationOptions | PublicKeyCredentialRequestOptions,
-        ) -> tuple[CollectedClientData, str]:
-            if isinstance(options, PublicKeyCredentialCreationOptions):
-                request_type = "webauthn.create"
-                requested_rp_id = options.rp.id
-                challenge = options.challenge
-            elif isinstance(options, PublicKeyCredentialRequestOptions):
-                request_type = "webauthn.get"
-                requested_rp_id = options.rp_id
-                challenge = options.challenge
-            else:
-                raise TypeError(f"unsupported options type: {type(options)!r}")
-            if requested_rp_id != self.rp_id:
-                raise ValueError(f"rp_id mismatch: expected {self.rp_id}, got {requested_rp_id}")
-            return CollectedClientData.create(
-                type=request_type,
-                challenge=challenge,
-                origin=self.origin,
-            ), self.rp_id
-
-else:
-    ProxyClientDataCollector = None
-
-
 class ProxyUserInteraction(UserInteraction):
     def prompt_up(self) -> None:
         print("Touch the ChromeCard to continue...", flush=True)
@@ -493,6 +504,7 @@ class ProxyState:
         rp_id: str,
         rp_name: str,
         origin: str,
+        direct_device_path: str,
     ):
         self.session_ttl_s = session_ttl_s
         self.auth_mode = auth_mode
@@ -503,14 +515,15 @@ class ProxyState:
         self.enrollment_db = enrollment_db
         self.rp_id = rp_id
         self.origin = origin
+        self.direct_device_path = direct_device_path
         self.lock = threading.Lock()
+        self.direct_device_lock = threading.RLock()
+        self.direct_device: CtapHidDevice | None = None
         self.sessions: dict[str, Session] = {}
         self.enrollments: dict[str, Enrollment] = {}
         self.rp = PublicKeyCredentialRpEntity(id=rp_id, name=rp_name)
         self.fido_server = Fido2Server(self.rp)
-        self.client_data_collector = (
+        self.client_data_collector = None
-            ProxyClientDataCollector(origin=origin, rp_id=rp_id) if ProxyClientDataCollector else None
-        )
         self.upstream = UpstreamPool(
             server_base_url=self.server_base_url,
             server_ca_file=self.server_ca_file,
@@ -595,16 +608,61 @@ class ProxyState:
         self.enrollment_db.write_text(json.dumps({"users": users}, indent=2) + "\n")
 
     def _new_fido_client(self) -> Fido2Client:
-        try:
+        device = self._get_direct_device()
-            device = next(CtapHidDevice.list_devices())
-        except StopIteration as exc:
-            raise RuntimeError("no CTAP HID devices found") from exc
         # Newer python-fido2 builds accept a custom client-data collector, while the
         # VM-side package still expects an origin string plus verifier callback.
         if self.client_data_collector is not None:
             return Fido2Client(device, self.client_data_collector, ProxyUserInteraction())
         return Fido2Client(device, self.origin, verify=verify_rp_id, user_interaction=ProxyUserInteraction())
 
+    def _open_direct_device(self) -> CtapHidDevice:
+        descriptor = get_descriptor(self.direct_device_path)
+        return CtapHidDevice(descriptor, open_connection(descriptor))
+
+    def _get_direct_device(self, *, force_reopen: bool = False) -> CtapHidDevice:
+        with self.direct_device_lock:
+            if force_reopen and self.direct_device is not None:
+                try:
+                    self.direct_device.close()
+                except Exception:
+                    pass
+                self.direct_device = None
+            if self.direct_device is None:
+                self.direct_device = self._open_direct_device()
+            return self.direct_device
+
+    def _with_direct_ctap2(self, action):
+        with self.direct_device_lock:
+            last_exc: Exception | None = None
+            for reopen in (False, True):
+                try:
+                    device = self._get_direct_device(force_reopen=reopen)
+                    return action(Ctap2(device))
+                except Exception as exc:
+                    last_exc = exc
+                    try:
+                        if self.direct_device is not None:
+                            self.direct_device.close()
+                    except Exception:
+                        pass
+                    self.direct_device = None
+            assert last_exc is not None
+            raise last_exc
+
+    def _collect_client_data(
+        self,
+        request_type: str,
+        options: PublicKeyCredentialCreationOptions | PublicKeyCredentialRequestOptions,
+    ) -> CollectedClientData:
+        requested_rp_id = options.rp.id if isinstance(options, PublicKeyCredentialCreationOptions) else options.rp_id
+        if requested_rp_id != self.rp_id:
+            raise RuntimeError(f"rp_id mismatch: expected {self.rp_id}, got {requested_rp_id}")
+        return CollectedClientData.create(
+            type=request_type,
+            challenge=options.challenge,
+            origin=self.origin,
+        )
+
     def _user_entity(self, username: str, display_name: str | None, user_id: bytes) -> PublicKeyCredentialUserEntity:
         return PublicKeyCredentialUserEntity(
             id=user_id,
@@ -646,9 +704,30 @@ class ProxyState:
             user_verification=UserVerificationRequirement.DISCOURAGED,
         )
         try:
+            client_data = self._collect_client_data("webauthn.create", options.public_key)
+            attestation = self._with_direct_ctap2(
+                lambda ctap2: ctap2.make_credential(
+                    client_data_hash=client_data.hash,
+                    rp=direct_ctap_rp(options.public_key.rp),
+                    user=direct_ctap_user(options.public_key.user),
+                    key_params=direct_ctap_key_params(),
+                    exclude_list=direct_ctap_allow_list(options.public_key.exclude_credentials),
+                    options={"rk": False, "uv": False},
+                )
+            )
             auth_data = self.fido_server.register_complete(
                 state,
-                self._new_fido_client().make_credential(options.public_key),
+                RegistrationResponse(
+                    id=attestation.auth_data.credential_data.credential_id,
+                    response=AuthenticatorAttestationResponse(
+                        client_data=client_data,
+                        attestation_object=AttestationObject.create(
+                            attestation.fmt,
+                            attestation.auth_data,
+                            attestation.att_stmt,
+                        ),
+                    ),
+                ),
             )
         except Exception as exc:
             raise RuntimeError(f"card registration failed: {exc}") from exc
@@ -750,9 +829,29 @@ class ProxyState:
                 [credential],
                 user_verification=UserVerificationRequirement.DISCOURAGED,
             )
-            selection = self._new_fido_client().get_assertion(options.public_key)
+            client_data = self._collect_client_data("webauthn.get", options.public_key)
-            assertion = selection.get_response(0)
+            assertion = self._with_direct_ctap2(
-            self.fido_server.authenticate_complete(state, [credential], assertion)
+                lambda ctap2: ctap2.get_assertion(
+                    rp_id=options.public_key.rp_id,
+                    client_data_hash=client_data.hash,
+                    allow_list=direct_ctap_allow_list(options.public_key.allow_credentials),
+                    options={"up": True, "uv": False},
+                )
+            )
+            response = assertion.assertions[0] if getattr(assertion, "assertions", None) else assertion
+            self.fido_server.authenticate_complete(
+                state,
+                [credential],
+                AuthenticationResponse(
+                    id=response.credential["id"],
+                    response=AuthenticatorAssertionResponse(
+                        client_data=client_data,
+                        authenticator_data=response.auth_data,
+                        signature=response.signature,
+                        user_handle=response.user.get("id") if response.user else None,
+                    ),
+                ),
+            )
         except Exception as exc:
             return False, f"assertion verification failed: {exc}"
         return True, "assertion verified"
@@ -1153,6 +1252,11 @@ def parse_args() -> argparse.Namespace:
         default="/home/user/chromecard/k_proxy_enrollments.json",
         help="JSON file used to persist enrolled usernames for the prototype",
     )
+    parser.add_argument(
+        "--direct-device-path",
+        default="/dev/hidraw0",
+        help="Explicit hidraw path used for direct FIDO2 mode",
+    )
     return parser.parse_args()
 
 
@@ -1175,6 +1279,7 @@ def main() -> int:
         rp_id=args.rp_id,
         rp_name=args.rp_name,
         origin=args.origin,
+        direct_device_path=args.direct_device_path,
     )
     Handler.state = state
     server = ThreadingHTTPServer((args.host, args.port), Handler)

phase5_chain_regression.sh

@@ -8,6 +8,10 @@ USERNAME="${USERNAME:-alice}"
 REQUESTS="${REQUESTS:-20}"
 PARALLELISM="${PARALLELISM:-8}"
 CONNECT_TIMEOUT="${CONNECT_TIMEOUT:-8}"
+LOGIN_TIMEOUT="${LOGIN_TIMEOUT:-90}"
+INTERACTIVE_CARD="${INTERACTIVE_CARD:-0}"
+EXPECT_AUTH_MODE="${EXPECT_AUTH_MODE:-}"
+SSH_CONFIG="${SSH_CONFIG:-/home/user/.ssh/config}"
 
 usage() {
   cat <<'EOF'
@@ -24,6 +28,10 @@ Options:
   --requests N             Number of counter requests to issue
   --parallelism N          Number of concurrent workers
   --connect-timeout SEC    SSH connect timeout
+  --login-timeout SEC      Timeout for the interactive login request (default: 90)
+  --interactive-card       Print card-confirmation instructions before login
+  --expect-auth-mode NAME  Require login response auth_mode to match
+  --ssh-config PATH        SSH config file to use (default: /home/user/.ssh/config)
   -h, --help               Show this help text
 EOF
 }
@@ -58,6 +66,22 @@ while [[ $# -gt 0 ]]; do
       CONNECT_TIMEOUT="$2"
       shift 2
       ;;
+    --login-timeout)
+      LOGIN_TIMEOUT="$2"
+      shift 2
+      ;;
+    --interactive-card)
+      INTERACTIVE_CARD=1
+      shift
+      ;;
+    --expect-auth-mode)
+      EXPECT_AUTH_MODE="$2"
+      shift 2
+      ;;
+    --ssh-config)
+      SSH_CONFIG="$2"
+      shift 2
+      ;;
     -h|--help)
       usage
       exit 0
@@ -70,7 +94,16 @@ while [[ $# -gt 0 ]]; do
   esac
 done
 
+if [[ "${INTERACTIVE_CARD}" == "1" ]]; then
+  cat <<EOF
+Starting interactive login for ${USERNAME}.
+When the card shows the authentication prompt, press yes to approve.
+Press no only if you want to reject the login.
+EOF
+fi
+
 ssh \
+  -F "${SSH_CONFIG}" \
   -o BatchMode=yes \
   -o StrictHostKeyChecking=accept-new \
   -o ConnectTimeout="${CONNECT_TIMEOUT}" \
@@ -81,6 +114,8 @@ ssh \
     USERNAME="${USERNAME}" \
     REQUESTS="${REQUESTS}" \
     PARALLELISM="${PARALLELISM}" \
+    LOGIN_TIMEOUT="${LOGIN_TIMEOUT}" \
+    EXPECT_AUTH_MODE="${EXPECT_AUTH_MODE}" \
     python3 - <<'PY'
 import concurrent.futures
 import json
@@ -95,6 +130,8 @@ proxy_url = os.environ["PROXY_URL"].rstrip("/")
 username = os.environ["USERNAME"]
 requests = int(os.environ["REQUESTS"])
 parallelism = int(os.environ["PARALLELISM"])
+login_timeout = int(os.environ["LOGIN_TIMEOUT"])
+expect_auth_mode = os.environ["EXPECT_AUTH_MODE"]
 
 if requests < 1:
     raise SystemExit("REQUESTS must be >= 1")
@@ -103,7 +140,7 @@ if parallelism < 1:
 
 ctx = ssl.create_default_context(cafile=ca_file)
 
-def post_json(path: str, payload: dict | None = None, token: str | None = None):
+def post_json(path: str, payload: dict | None = None, token: str | None = None, timeout: int = 10):
     data = None if payload is None else json.dumps(payload).encode("utf-8")
     headers = {}
     if payload is not None:
@@ -117,7 +154,7 @@ def post_json(path: str, payload: dict | None = None, token: str | None = None):
         method="POST",
     )
     try:
-        with urllib.request.urlopen(req, context=ctx, timeout=10) as resp:
+        with urllib.request.urlopen(req, context=ctx, timeout=timeout) as resp:
             return resp.status, json.loads(resp.read().decode("utf-8"))
     except urllib.error.HTTPError as exc:
         body = exc.read().decode("utf-8")
@@ -127,10 +164,23 @@ def post_json(path: str, payload: dict | None = None, token: str | None = None):
             payload = {"ok": False, "error": body}
         return exc.code, payload
 
-status, login = post_json("/session/login", {"username": username})
+status, login = post_json("/session/login", {"username": username}, timeout=login_timeout)
 if status != 200 or "session_token" not in login:
     print(json.dumps({"ok": False, "stage": "login", "status": status, "response": login}))
     raise SystemExit(1)
+if expect_auth_mode and login.get("auth_mode") != expect_auth_mode:
+    print(
+        json.dumps(
+            {
+                "ok": False,
+                "stage": "login",
+                "error": "unexpected auth_mode",
+                "expected": expect_auth_mode,
+                "response": login,
+            }
+        )
+    )
+    raise SystemExit(1)
 
 token = login["session_token"]
 values = []

raw_ctap_probe.py

@@ -22,6 +22,7 @@ try:
     from fido2.ctap import CtapError
     from fido2.ctap2 import Ctap2
     from fido2.hid import CtapHidDevice
+    from fido2.hid.linux import get_descriptor, open_connection
 except Exception as exc:
     print("Missing dependency: python-fido2", file=sys.stderr)
     print("Install with: python3 -m pip install fido2", file=sys.stderr)
@@ -66,6 +67,18 @@ def get_ctap2(dev: CtapHidDevice) -> Ctap2:
     return Ctap2(dev)
 
 
+def get_device(index: int, device_path: str | None) -> CtapHidDevice:
+    if device_path:
+        descriptor = get_descriptor(device_path)
+        return CtapHidDevice(descriptor, open_connection(descriptor))
+    devs = list_devices()
+    if not devs:
+        raise SystemExit("No CTAP HID devices found.")
+    if index < 0 or index >= len(devs):
+        raise SystemExit(f"Invalid --index {index}; found {len(devs)} device(s).")
+    return devs[index]
+
+
 def print_json(payload: dict[str, Any]) -> None:
     print(json.dumps(payload, indent=2, default=_json_default))
 
@@ -251,6 +264,10 @@ def do_get_assertion(ctap2: Ctap2, args: argparse.Namespace, device_meta: dict[s
 def build_parser() -> argparse.ArgumentParser:
     parser = argparse.ArgumentParser(description="Low-level CTAP2 host probe")
     parser.add_argument("--index", type=int, default=0, help="Device index from --list output")
+    parser.add_argument(
+        "--device-path",
+        help="Use a specific hidraw node such as /dev/hidraw0 instead of scanning all devices",
+    )
     subparsers = parser.add_subparsers(dest="command", required=True)
 
     subparsers.add_parser("list", help="List CTAP HID devices")
@@ -277,8 +294,8 @@ def main() -> int:
     parser = build_parser()
     args = parser.parse_args()
 
-    devs = list_devices()
     if args.command == "list":
+        devs = list_devices()
         print_json(
             {
                 "devices": [describe_device(dev) for dev in devs],
@@ -286,14 +303,7 @@ def main() -> int:
         )
         return 0 if devs else 1
 
-    if not devs:
+    dev = get_device(args.index, args.device_path)
-        print("No CTAP HID devices found.", file=sys.stderr)
-        return 1
-    if args.index < 0 or args.index >= len(devs):
-        print(f"Invalid --index {args.index}; found {len(devs)} device(s).", file=sys.stderr)
-        return 2
-
-    dev = devs[args.index]
     device_meta = describe_device(dev)
     ctap2 = get_ctap2(dev)