webauthn: provide caBLE status updates.

Plumb though better error information (for a future change) and some
status updates. Use the status updates to visually indicate the progress
of a QR transaction.

BUG=1002262

Change-Id: I94ce3abf4accb5b28273fc5ee6a9f07386f64d0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2511975
Commit-Queue: Adam Langley <agl@chromium.org>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Cr-Commit-Position: refs/heads/master@{#825952}

chrome/android/features/cablev2_authenticator/BUILD.gn

@@ -47,6 +47,8 @@ android_resources("java_resources") {
     "java/res/layout/cablev2_fcm.xml",
     "java/res/layout/cablev2_qr_scan.xml",
     "java/res/layout/cablev2_usb_attached.xml",
+    "java/res/values/attrs.xml",
+    "java/res/values/styles.xml",
   ]
   deps = [ "//chrome/android:chrome_app_java_resources" ]
 }

chrome/android/features/cablev2_authenticator/java/res/drawable/header.xml

@@ -12,12 +12,15 @@
       android:fillColor="@color/modern_grey_200"
       android:fillType="nonZero"/>
   <path
-      android:pathData="M329.278,37.36L329.278,32.145c10.735,0 19.175,-3 25.1,-8.955 9.3,-9.36 9.325,-23.015 9.325,-23.15l5.25,-0.04c0,0.645 0,15.9 -10.815,26.82 -6.935,6.995 -16.645,10.54 -28.85,10.54z"
+      android:pathData="m358.92,31.398v-4.363c8.982,0 16.043,-2.51 21.001,-7.493 7.781,-7.831 7.802,-19.256 7.802,-19.369l4.393,-0.033c0,0.54 0,13.303 -9.049,22.44 -5.802,5.853 -13.927,8.819 -24.138,8.819z"
+      android:strokeWidth="0.836685"
       android:fillColor="@color/modern_grey_200"
       android:fillType="nonZero"/>
   <path
-      android:pathData="m294.563,68.145h-5.245a40.45,40.45 0,0 1,5 -18c4.605,-8.2 14.4,-18 34.96,-18v5.215c-14.465,0 -24.685,5.17 -30.385,15.36A35.35,35.35 0,0 0,294.563 68.145Z"
+      android:pathData="m329.875,57.155h-4.388a33.844,33.844 0,0 1,4.183 -15.06c3.853,-6.861 12.048,-15.06 29.251,-15.06v4.363c-12.103,0 -20.654,4.326 -25.423,12.851a29.577,29.577 0,0 0,-3.623 12.906z"
+      android:strokeWidth="0.836685"
       android:fillColor="@color/google_blue_grey_500"
+      android:fillAlpha="1"
       android:fillType="nonZero"/>
   <path
       android:pathData="m285.609,35.639h-17.28a8.64,8.64 0,0 1,17.28 0zM203.784,55.404h20v4h-20z"
@@ -55,7 +58,7 @@
       android:pathData="M39.297,23.65L69.526,23.65A8.613,8.613 0,0 1,78.139 32.263L78.139,100.309A8.613,8.613 0,0 1,69.526 108.923L39.297,108.923A8.613,8.613 0,0 1,30.684 100.309L30.684,32.263A8.613,8.613 0,0 1,39.297 23.65z"
       android:strokeAlpha="1"
       android:strokeWidth="1.368"
-      android:strokeColor="@color/modern_grey_500"
+      android:strokeColor="?attr/phone_stroke"
       android:strokeLineCap="round"/>
   <path
       android:pathData="M84.304,41.552m-18.974,0a18.974,18.974 0,1 1,37.948 0a18.974,18.974 0,1 1,-37.948 0"
@@ -72,9 +75,9 @@
       android:fillAlpha="1"
       android:strokeLineCap="round"/>
   <path
-      android:pathData="m370.758,33.052c-2.393,0 -4.318,1.926 -4.318,4.318v59.451c0,0.185 0.03,0.362 0.053,0.541h90.072c0.022,-0.179 0.055,-0.356 0.055,-0.541L456.619,37.37c0,-2.393 -1.926,-4.318 -4.318,-4.318z"
+      android:pathData="m370.758,33.052c-2.393,0 -4.318,1.926 -4.318,4.318v59.451c0,0.185 0.03,0.362 0.053,0.541h90.072c0.022,-0.179 0.055,-0.356 0.055,-0.541V37.37c0,-2.393 -1.926,-4.318 -4.318,-4.318z"
       android:strokeWidth="1.368"
-      android:strokeColor="@color/modern_grey_500"
+      android:strokeColor="?attr/laptop_stroke"
       android:fillAlpha="1"
       android:strokeLineCap="round"/>
   <path
@@ -82,7 +85,7 @@
       android:strokeAlpha="1"
       android:strokeLineJoin="miter"
       android:strokeWidth="1.368"
-      android:strokeColor="@color/modern_grey_500"
+      android:strokeColor="?attr/laptop_stroke"
       android:fillType="evenOdd"
       android:strokeLineCap="butt"/>
   <path
@@ -91,4 +94,22 @@
       android:strokeWidth="1.92357"
       android:strokeColor="@color/modern_grey_500"
       android:strokeLineCap="round"/>
+  <path
+      android:pathData="M80.268,67.561H209.122"
+      android:strokeAlpha="?attr/link1_alpha"
+      android:strokeLineJoin="miter"
+      android:strokeWidth="2.26772"
+      android:strokeColor="@color/google_green_600"
+      android:fillType="evenOdd"
+      android:fillAlpha="0"
+      android:strokeLineCap="round"/>
+  <path
+      android:pathData="m260.684,67.561 l103.061,0"
+      android:strokeAlpha="?attr/link2_alpha"
+      android:strokeLineJoin="miter"
+      android:strokeWidth="2.26772"
+      android:strokeColor="@color/google_green_600"
+      android:fillType="evenOdd"
+      android:fillAlpha="0"
+      android:strokeLineCap="round"/>
 </vector>

chrome/android/features/cablev2_authenticator/java/res/layout/cablev2_qr_scan.xml

@@ -13,8 +13,7 @@
       android:layout_width="match_parent"
       android:layout_height="100dp"
       android:layout_marginBottom="24dp"
-      android:background ="@color/modern_grey_50"
-      android:src="@drawable/header" />
+      android:background ="@color/modern_grey_50" />
 
   <LinearLayout
       android:id="@+id/qr_scan"

chrome/android/features/cablev2_authenticator/java/res/values/attrs.xml

+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <declare-styleable name="header">
+        <attr name="phone_stroke" format="color" />
+        <attr name="laptop_stroke" format="color" />
+        <attr name="link1_alpha" format="float" />
+        <attr name="link2_alpha" format="float" />
+    </declare-styleable>
+</resources>

chrome/android/features/cablev2_authenticator/java/res/values/styles.xml

+<resources>
+    <style name="idle">
+        <item name="phone_stroke">@color/modern_grey_500</item>
+        <item name="laptop_stroke">@color/modern_grey_500</item>
+        <item name="link1_alpha">0</item>
+        <item name="link2_alpha">0</item>
+    </style>
+
+    <style name="step1">
+        <item name="phone_stroke">@color/modern_blue_800</item>
+        <item name="laptop_stroke">@color/modern_grey_500</item>
+        <item name="link1_alpha">0</item>
+        <item name="link2_alpha">0</item>
+    </style>
+
+    <style name="step2">
+        <item name="phone_stroke">@color/modern_blue_800</item>
+        <item name="laptop_stroke">@color/modern_grey_500</item>
+        <item name="link1_alpha">1</item>
+        <item name="link2_alpha">0</item>
+    </style>
+
+    <style name="step3">
+        <item name="phone_stroke">@color/modern_blue_800</item>
+        <item name="laptop_stroke">@color/modern_grey_500</item>
+        <item name="link1_alpha">1</item>
+        <item name="link2_alpha">1</item>
+    </style>
+
+    <style name="step4">
+        <item name="phone_stroke">@color/modern_blue_800</item>
+        <item name="laptop_stroke">@color/modern_blue_800</item>
+        <item name="link1_alpha">1</item>
+        <item name="link2_alpha">1</item>
+    </style>
+</resources>

chrome/android/features/cablev2_authenticator/java/src/org/chromium/chrome/browser/webauth/authenticator/CableAuthenticator.java

@@ -104,6 +104,9 @@ class CableAuthenticator {
         void onAuthenticatorResult(Result result);
         // Invoked when the authenticator has finished. The UI should be dismissed at this point.
         void onComplete();
+        // Called when an informative status update is available. The argument has the same values
+        // as the Status enum from v2_authenticator.h.
+        void onStatus(int code);
     }
 
     public CableAuthenticator(Context context, CableAuthenticatorUI ui, long networkContext,
@@ -162,6 +165,13 @@ class CableAuthenticator {
 
     // Calls from native code.
 
+    // Called when an informative status update is available. The argument has the same values
+    // as the Status enum from v2_authenticator.h.
+    @CalledByNative
+    public void onStatus(int code) {
+        mCallback.onStatus(code);
+    }
+
     @CalledByNative
     public static BLEAdvert newBLEAdvert(byte[] payload) {
         return new BLEAdvert(payload);

chrome/android/features/cablev2_authenticator/java/src/org/chromium/chrome/browser/webauth/authenticator/CableAuthenticatorUI.java

@@ -10,15 +10,19 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
+import android.graphics.drawable.Drawable;
 import android.hardware.usb.UsbAccessory;
 import android.hardware.usb.UsbManager;
 import android.os.Bundle;
+import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
+import android.widget.ImageView;
 import android.widget.LinearLayout;
 
+import androidx.core.content.res.ResourcesCompat;
 import androidx.fragment.app.Fragment;
 
 import org.chromium.ui.base.ActivityAndroidPermissionDelegate;
@@ -41,6 +45,7 @@ public class CableAuthenticatorUI extends Fragment
     private AndroidPermissionDelegate mPermissionDelegate;
     private CableAuthenticator mAuthenticator;
     private LinearLayout mQRButton;
+    private ImageView mHeader;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -94,6 +99,9 @@ public class CableAuthenticatorUI extends Fragment
                 mQRButton = v.findViewById(R.id.qr_scan);
                 mQRButton.setOnClickListener(this);
 
+                mHeader = v.findViewById(R.id.qr_image);
+                setHeader(R.style.idle);
+
                 return v;
         }
 
@@ -101,6 +109,18 @@ public class CableAuthenticatorUI extends Fragment
         return null;
     }
 
+    /**
+     * Updates the header image to be shown in a new "style". The Android
+     * style system is used to make certain elements appear as a QR handshake
+     * progresses.
+     */
+    private void setHeader(int style) {
+        ContextThemeWrapper theme = new ContextThemeWrapper(getContext(), style);
+        Drawable drawable =
+                ResourcesCompat.getDrawable(getResources(), R.drawable.header, theme.getTheme());
+        mHeader.setImageDrawable(drawable);
+    }
+
     /**
      * Called when the button to scan a QR code is pressed.
      */
@@ -135,9 +155,28 @@ public class CableAuthenticatorUI extends Fragment
     @Override
     @SuppressLint("SetTextI18n")
     public void onQRCode(String value) {
+        setHeader(R.style.step1);
         mAuthenticator.onQRCode(value);
     }
 
+    @Override
+    public void onStatus(int code) {
+        if (mMode != Mode.QR) {
+            // In FCM mode, the handshake is done before the UI appears. For
+            // USB everything should happen immediately.
+            return;
+        }
+
+        // These values must match up with the Status enum in v2_authenticator.h
+        if (code == 1) {
+            setHeader(R.style.step2);
+        } else if (code == 2) {
+            setHeader(R.style.step3);
+        } else if (code == 3) {
+            setHeader(R.style.step4);
+        }
+    }
+
     /**
      * Called when camera permission has been requested and the user has resolved the permission
      * request.

chrome/android/features/cablev2_authenticator/native/cablev2_authenticator_android.cc

@@ -235,7 +235,18 @@ class AndroidPlatform : public device::cablev2::authenticator::Platform {
     NeedInteractive();
   }
 
-  void OnCompleted(bool success) override {
+  void OnStatus(Status status) override {
+    DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+
+    if (!cable_authenticator_) {
+      return;
+    }
+
+    Java_CableAuthenticator_onStatus(env_, cable_authenticator_,
+                                     static_cast<int>(status));
+  }
+
+  void OnCompleted(base::Optional<Error> maybe_error) override {
     // The transaction might fail before interactive mode, thus
     // |cable_authenticator_| may be empty.
     if (cable_authenticator_) {
@@ -357,9 +368,8 @@ class USBTransport : public device::cablev2::authenticator::Transport {
 
   // Transport:
   void StartReading(
-      base::RepeatingCallback<void(base::Optional<std::vector<uint8_t>>)>
-          read_callback) override {
-    callback_ = read_callback;
+      base::RepeatingCallback<void(Update)> update_callback) override {
+    callback_ = update_callback;
     Java_USBHandler_startReading(env_, usb_device_);
   }
 
@@ -370,7 +380,7 @@ class USBTransport : public device::cablev2::authenticator::Transport {
  private:
   void OnData(base::Optional<base::span<const uint8_t>> data) {
     if (!data) {
-      callback_.Run(base::nullopt);
+      callback_.Run(Disconnected::kDisconnected);
     } else {
       callback_.Run(device::fido_parsing_utils::Materialize(*data));
     }
@@ -378,7 +388,7 @@ class USBTransport : public device::cablev2::authenticator::Transport {
 
   JNIEnv* const env_;
   const ScopedJavaGlobalRef<jobject> usb_device_;
-  base::RepeatingCallback<void(base::Optional<std::vector<uint8_t>>)> callback_;
+  base::RepeatingCallback<void(Update)> callback_;
   base::WeakPtrFactory<USBTransport> weak_factory_{this};
 };
 

device/fido/cable/v2_authenticator.cc

@@ -283,12 +283,11 @@ class TunnelTransport : public Transport {
   // Transport:
 
   void StartReading(
-      base::RepeatingCallback<void(base::Optional<std::vector<uint8_t>>)>
-          read_callback) override {
+      base::RepeatingCallback<void(Update)> update_callback) override {
     DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-    DCHECK(!read_callback_);
+    DCHECK(!update_callback_);
 
-    read_callback_ = std::move(read_callback);
+    update_callback_ = std::move(update_callback);
 
     network_context_->CreateWebSocket(
         target_, {device::kCableWebSocketProtocol}, net::SiteForCookies(),
@@ -336,7 +335,7 @@ class TunnelTransport : public Transport {
 
     if (!ok) {
       FIDO_LOG(ERROR) << "Failed to connect to tunnel server";
-      read_callback_.Run(base::nullopt);
+      update_callback_.Run(Platform::Error::TUNNEL_SERVER_CONNECT_FAILED);
       return;
     }
 
@@ -363,6 +362,8 @@ class TunnelTransport : public Transport {
     std::vector<uint8_t> msg =
         handshaker_->BuildInitialMessage(BuildGetInfoResponse());
     websocket_client_->Write(msg);
+
+    update_callback_.Run(Platform::Status::TUNNEL_SERVER_CONNECT);
   }
 
   void OnTunnelData(base::Optional<base::span<const uint8_t>> msg) {
@@ -370,7 +371,7 @@ class TunnelTransport : public Transport {
 
     if (!msg) {
       FIDO_LOG(DEBUG) << "WebSocket tunnel closed";
-      read_callback_.Run(base::nullopt);
+      update_callback_.Run(Disconnected::kDisconnected);
       return;
     }
 
@@ -383,10 +384,11 @@ class TunnelTransport : public Transport {
         handshaker_.reset();
         if (!result) {
           FIDO_LOG(ERROR) << "caBLE handshake failure";
-          read_callback_.Run(base::nullopt);
+          update_callback_.Run(Platform::Error::HANDSHAKE_FAILED);
           return;
         }
         FIDO_LOG(DEBUG) << "caBLE handshake complete";
+        update_callback_.Run(Platform::Status::HANDSHAKE_COMPLETE);
         crypter_ = std::move(result->first);
 
         if (state_ == State::kConnected) {
@@ -409,11 +411,15 @@ class TunnelTransport : public Transport {
         std::vector<uint8_t> plaintext;
         if (!crypter_->Decrypt(*msg, &plaintext)) {
           FIDO_LOG(ERROR) << "failed to decrypt caBLE message";
-          read_callback_.Run(base::nullopt);
+          update_callback_.Run(Platform::Error::DECRYPT_FAILURE);
           return;
         }
 
-        read_callback_.Run(plaintext);
+        if (first_message_) {
+          update_callback_.Run(Platform::Status::REQUEST_RECEIVED);
+          first_message_ = false;
+        }
+        update_callback_.Run(std::move(plaintext));
         break;
       }
 
@@ -450,8 +456,8 @@ class TunnelTransport : public Transport {
   bssl::UniquePtr<EC_KEY> local_identity_;
   GURL target_;
   std::unique_ptr<Platform::BLEAdvert> ble_advert_;
-  base::RepeatingCallback<void(base::Optional<std::vector<uint8_t>>)>
-      read_callback_;
+  base::RepeatingCallback<void(Update)> update_callback_;
+  bool first_message_ = true;
 
   SEQUENCE_CHECKER(sequence_checker_);
 };
@@ -461,25 +467,34 @@ class CTAP2Processor : public Transaction {
   CTAP2Processor(std::unique_ptr<Transport> transport,
                  std::unique_ptr<Platform> platform)
       : transport_(std::move(transport)), platform_(std::move(platform)) {
-    transport_->StartReading(
-        base::BindRepeating(&CTAP2Processor::OnData, base::Unretained(this)));
+    transport_->StartReading(base::BindRepeating(
+        &CTAP2Processor::OnTransportUpdate, base::Unretained(this)));
   }
 
  private:
-  void OnData(base::Optional<std::vector<uint8_t>> msg) {
+  void OnTransportUpdate(Transport::Update update) {
     DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 
-    if (!msg) {
-      FIDO_LOG(ERROR) << "Closing transaction due to transport EOF";
-      platform_->OnCompleted(transaction_done_);
+    if (auto* error = absl::get_if<Platform::Error>(&update)) {
+      platform_->OnCompleted(*error);
+      return;
+    } else if (auto* status = absl::get_if<Platform::Status>(&update)) {
+      platform_->OnStatus(*status);
+      return;
+    } else if (absl::get_if<Transport::Disconnected>(&update)) {
+      base::Optional<Platform::Error> maybe_error;
+      if (!transaction_done_) {
+        maybe_error = Platform::Error::UNEXPECTED_EOF;
+      }
+      platform_->OnCompleted(maybe_error);
       return;
     }
 
-    base::Optional<std::vector<uint8_t>> response = ProcessCTAPMessage(*msg);
+    std::vector<uint8_t>& msg = absl::get<std::vector<uint8_t>>(update);
+    base::Optional<std::vector<uint8_t>> response = ProcessCTAPMessage(msg);
     if (!response) {
-      // Fatal error.
-      // TODO: need to signal this to the UI.
-      platform_->OnCompleted(false);
+      // TODO(agl): expose more error information from |ProcessCTAPMessage|.
+      platform_->OnCompleted(Platform::Error::INVALID_CTAP);
       return;
     }
 

device/fido/cable/v2_authenticator.h

@@ -16,6 +16,7 @@
 #include "device/fido/cable/v2_constants.h"
 #include "device/fido/fido_constants.h"
 #include "services/network/public/mojom/network_context.mojom-forward.h"
+#include "third_party/abseil-cpp/absl/types/variant.h"
 
 namespace device {
 namespace cablev2 {
@@ -35,6 +36,23 @@ class Platform {
 
   virtual ~Platform();
 
+  enum class Status {
+    TUNNEL_SERVER_CONNECT = 1,
+    HANDSHAKE_COMPLETE = 2,
+    REQUEST_RECEIVED = 3,
+  };
+
+  enum class Error {
+    UNEXPECTED_EOF = 100,
+    TUNNEL_SERVER_CONNECT_FAILED = 101,
+    HANDSHAKE_FAILED = 102,
+    DECRYPT_FAILURE = 103,
+    INVALID_CBOR = 104,
+    INVALID_CTAP = 105,
+    UNKNOWN_COMMAND = 106,
+    INTERNAL_ERROR = 107,
+  };
+
   using MakeCredentialCallback =
       base::OnceCallback<void(uint32_t status,
                               base::span<const uint8_t> client_data_json,
@@ -82,10 +100,13 @@ class Platform {
 
   virtual void GetAssertion(std::unique_ptr<GetAssertionParams> params) = 0;
 
+  // OnStatus is called when a new informative status is available.
+  virtual void OnStatus(Status) = 0;
+
   // OnCompleted is called when the transaction has completed. Note that calling
   // this may result in the |Transaction| that owns this |Platform| being
   // deleted.
-  virtual void OnCompleted(bool success) = 0;
+  virtual void OnCompleted(base::Optional<Error>) = 0;
 
   virtual std::unique_ptr<BLEAdvert> SendBLEAdvert(
       base::span<const uint8_t, kAdvertSize> payload) = 0;
@@ -95,13 +116,23 @@ class Platform {
 // The framing of messages must be preserved.
 class Transport {
  public:
+  // Disconnected is a fresh type in order to be distinguishable in |Update|.
+  enum class Disconnected { kDisconnected = 200 };
+
+  // Update is a sum type of all the possible signals that a transport can
+  // report. The first element is a message from the peer. |Disconnected| is
+  // handled separately because it's context dependent whether that is an error
+  // or not.
+  using Update = absl::variant<std::vector<uint8_t>,
+                               Platform::Error,
+                               Platform::Status,
+                               Disconnected>;
   virtual ~Transport();
 
   // StartReading requests that the given callback be called whenever a message
-  // arrives from the peer.
+  // arrives from the peer, an error occurs, or the status of the link changes.
   virtual void StartReading(
-      base::RepeatingCallback<void(base::Optional<std::vector<uint8_t>>)>
-          read_callback) = 0;
+      base::RepeatingCallback<void(Update)> update_callback) = 0;
   virtual void Write(std::vector<uint8_t> data) = 0;
 };
 

device/fido/cable/v2_test_util.cc

@@ -378,7 +378,8 @@ class TestPlatform : public authenticator::Platform {
     NOTREACHED();
   }
 
-  void OnCompleted(bool success) override {}
+  void OnStatus(Status status) override {}
+  void OnCompleted(base::Optional<Error> maybe_error) override {}
 
   std::unique_ptr<authenticator::Platform::BLEAdvert> SendBLEAdvert(
       base::span<const uint8_t, kAdvertSize> payload) override {