Initial release of the Key Attestation Verifier app.

Key changes include:
- Relocating all source files and resources.
- Updating the package name to com.android.attestation.app.
- Generalizing UI strings and colors.
- Moving the "Attest Device IDs" toggle to the main activity layout.
- Adding BUILD targets for the Android library and binary.

PiperOrigin-RevId: 893416680

Author: naznia-dev

java/com/android/attestation/app/AndroidManifest.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.attestation.app">
+
+    <uses-sdk android:minSdkVersion="33" android:targetSdkVersion="33"/>
+    <application
+        android:allowBackup="true"
+        android:label="@string/app_name"
+        android:supportsRtl="true"
+        android:theme="@style/AppTheme"
+        android:icon="@drawable/ic_launcher_verifier"
+        android:roundIcon="@drawable/ic_launcher_verifier">
+
+        <activity android:name=".MainActivity" android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+</manifest>

java/com/android/attestation/app/AttestationUiManager.java

@@ -0,0 +1,99 @@
+/*
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.attestation.app;
+
+import android.app.Activity;
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.Network;
+import android.net.NetworkCapabilities;
+import android.security.KeyStoreException;
+import com.google.android.material.dialog.MaterialAlertDialogBuilder;
+import java.net.ConnectException;
+import java.net.SocketTimeoutException;
+import java.net.UnknownHostException;
+
+/**
+ * Utility class providing helper methods to verify Android device states, build configurations, and
+ * user profile environments.
+ */
+public final class AttestationUtils {
+
+  public static void showAlertDialog(
+      Activity activity, String title, String message, String buttonText) {
+    new MaterialAlertDialogBuilder(activity)
+        .setTitle(title)
+        .setMessage(message)
+        .setPositiveButton(buttonText, null)
+        .setCancelable(false)
+        .show();
+  }
+
+  /**
+   * Returns {@code true} if the network is likely available, or if its status cannot be determined.
+   *
+   * <p>This method fails open: it returns {@code false} only when it's definitively known that the
+   * network is unavailable. If there's insufficient information or an exception occurs during the
+   * check, it defaults to returning {@code true}.
+   */
+  public static boolean isNetworkAvailable(Context context) {
+    try {
+      ConnectivityManager cm =
+          (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
+
+      if (cm == null) {
+        return true;
+      }
+
+      Network activeNetwork = cm.getActiveNetwork();
+      if (activeNetwork == null) {
+        return false;
+      }
+
+      NetworkCapabilities capabilities = cm.getNetworkCapabilities(activeNetwork);
+      return capabilities == null
+          || capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+
+    } catch (RuntimeException e) {
+      return true;
+    }
+  }
+
+  public static boolean isCannotAttestIdsError(Exception e) {
+    int errorCode = getKeystoreErrorCode(e);
+
+    return errorCode == KeyStoreException.ERROR_ID_ATTESTATION_FAILURE;
+  }
+
+  public static boolean isNetworkError(Exception e) {
+    int errorCode = getKeystoreErrorCode(e);
+
+    return errorCode == KeyStoreException.RETRY_WHEN_CONNECTIVITY_AVAILABLE
+        || e instanceof UnknownHostException
+        || e instanceof SocketTimeoutException
+        || e instanceof ConnectException;
+  }
+
+  private static int getKeystoreErrorCode(Exception e) {
+    Throwable throwable = e instanceof KeyStoreException ? e : e.getCause();
+    if (throwable instanceof KeyStoreException kse) {
+      return kse.getNumericErrorCode();
+    }
+    return Integer.MAX_VALUE;
+  }
+
+  private AttestationUtils() {}
+}