デバイスのセキュリティ状態を公開する

// Kotlin DSL (build.gradle.kts)
dependencies {
    // Core provider library for OTA and system update clients
    implementation("androidx.security:security-state-provider:1.0.0")
    // Required to construct UpdateInfo and DateBasedSecurityPatchLevel records
    implementation("androidx.security:security-state:1.1.0")
    // Optional: Guava ListenableFuture support for Java implementations
    implementation("androidx.concurrent:concurrent-futures:1.2.0")
    implementation("com.google.guava:guava:33.0.0-android")
}

// Groovy DSL (build.gradle)
dependencies {
    // Core provider library for OTA and system update clients
    implementation 'androidx.security:security-state-provider:1.0.0'
    // Required to construct UpdateInfo and DateBasedSecurityPatchLevel records
    implementation 'androidx.security:security-state:1.1.0'
    // Optional: Guava ListenableFuture support for Java implementations
    implementation 'androidx.concurrent:concurrent-futures:1.2.0'
    implementation 'com.google.guava:guava:33.0.0-android'
}

import android.content.Context
import androidx.security.state.SecurityPatchState
import androidx.security.state.SecurityPatchState.DateBasedSecurityPatchLevel
import androidx.security.state.UpdateInfo
import androidx.security.state.provider.UpdateInfoManager
import androidx.work.CoroutineWorker
import androidx.work.WorkerParameters
import kotlin.math.max

class OtaSyncWorker(context: Context, params: WorkerParameters) : CoroutineWorker(context, params) {
    override suspend fun doWork(): Result {
        val updateInfoManager = UpdateInfoManager(applicationContext)
        val securityPatchState = SecurityPatchState(applicationContext)
        val currentSpl = securityPatchState.getDeviceSecurityPatchLevel(SecurityPatchState.COMPONENT_SYSTEM)

        // 1. Fetch available update metadata from OEM backend
        val latestUpdate = MyOtaClient.fetchLatestSystemUpdate()
        val targetSplString = latestUpdate?.spl?.trim()
        val targetSpl = if (!targetSplString.isNullOrEmpty()) {
            DateBasedSecurityPatchLevel.fromString(targetSplString)
        } else {
            null
        }

        // 2. Defensively verify that target SPL is non-blank AND strictly newer than installed DSPL.
        // If an update is a maintenance patch with no SPL increment (or if no update is available),
        // unregister any stale cached record for this component.
        if (latestUpdate != null && targetSpl != null && targetSpl > currentSpl) {
            val updateInfo = UpdateInfo.Builder()
                .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                .setSecurityPatchLevel(targetSpl)
                .setPublishedDateMillis(latestUpdate.releaseTimeMillis)
                .setLastCheckTimeMillis(System.currentTimeMillis())
                .build()
            updateInfoManager.registerUpdate(updateInfo)
        } else {
            val clearTarget = UpdateInfo.Builder()
                .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                .build()
            updateInfoManager.unregisterUpdate(clearTarget)
        }

        // 3. Update global freshness timestamp (monotonic synchronization)
        val currentCheckTime = System.currentTimeMillis()
        val previousCheckTime = updateInfoManager.getLastCheckTimeMillis()
        updateInfoManager.setLastCheckTimeMillis(max(previousCheckTime, currentCheckTime))
        return Result.success()
    }
}

import android.content.Context;
import android.text.TextUtils;
import androidx.annotation.NonNull;
import androidx.security.state.SecurityPatchState;
import androidx.security.state.SecurityPatchState.DateBasedSecurityPatchLevel;
import androidx.security.state.SecurityPatchState.SecurityPatchLevel;
import androidx.security.state.UpdateInfo;
import androidx.security.state.provider.UpdateInfoManager;
import androidx.work.Worker;
import androidx.work.WorkerParameters;

public class OtaSyncWorker extends Worker {
    public OtaSyncWorker(@NonNull Context context, @NonNull WorkerParameters params) {
        super(context, params);
    }

    @NonNull
    @Override
    public Result doWork() {
        // In Java, pass null for customSecurityState because UpdateInfoManager does not declare @JvmOverloads
        UpdateInfoManager updateInfoManager =
                new UpdateInfoManager(getApplicationContext(), /* customSecurityState= */ null);
        SecurityPatchState securityPatchState = new SecurityPatchState(getApplicationContext());
        SecurityPatchLevel currentSpl =
                securityPatchState.getDeviceSecurityPatchLevel(SecurityPatchState.COMPONENT_SYSTEM);

        // 1. Fetch available update metadata from OEM backend
        MyOtaUpdate latestUpdate = MyOtaClient.fetchLatestSystemUpdate();
        String targetSplString = (latestUpdate != null && latestUpdate.getSpl() != null)
                ? latestUpdate.getSpl().trim()
                : null;
        DateBasedSecurityPatchLevel targetSpl =
                !TextUtils.isEmpty(targetSplString)
                        ? DateBasedSecurityPatchLevel.fromString(targetSplString)
                        : null;

        // 2. Defensively verify that target SPL is non-blank AND strictly newer than installed DSPL.
        // If an update is a maintenance patch with no SPL increment (or if no update is available),
        // unregister any stale cached record for this component.
        if (latestUpdate != null && targetSpl != null && targetSpl.compareTo(currentSpl) > 0) {
            UpdateInfo updateInfo = new UpdateInfo.Builder()
                    .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                    .setSecurityPatchLevel(targetSpl)
                    .setPublishedDateMillis(latestUpdate.getReleaseTimeMillis())
                    .setLastCheckTimeMillis(System.currentTimeMillis())
                    .build();
            updateInfoManager.registerUpdate(updateInfo);
        } else {
            UpdateInfo clearTarget = new UpdateInfo.Builder()
                    .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                    .build();
            updateInfoManager.unregisterUpdate(clearTarget);
        }

        // 3. Update global freshness timestamp (monotonic synchronization)
        long currentCheckTime = System.currentTimeMillis();
        long previousCheckTime = updateInfoManager.getLastCheckTimeMillis();
        updateInfoManager.setLastCheckTimeMillis(Math.max(previousCheckTime, currentCheckTime));
        return Result.success();
    }
}

import androidx.security.state.UpdateInfo
import androidx.security.state.provider.UpdateInfoService

class PushUpdateInfoService : UpdateInfoService() {
    // Cache is populated out-of-band by background sync tasks
    override fun shouldFetchUpdates(): Boolean = false

    // Never invoked under normal flow because shouldFetchUpdates() returns false
    override suspend fun fetchUpdates(): List<UpdateInfo> = emptyList()
}

import androidx.annotation.NonNull;
import androidx.security.state.UpdateInfo;
import androidx.security.state.provider.ListenableFutureUpdateInfoService;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.Collections;
import java.util.List;

public class PushUpdateInfoService extends ListenableFutureUpdateInfoService {
    @Override
    protected boolean shouldFetchUpdates() {
        return false;
    }

    @NonNull
    @Override
    protected ListenableFuture<List<UpdateInfo>> fetchUpdatesAsync() {
        return Futures.immediateFuture(Collections.emptyList());
    }
}

package com.example.android.updater

import androidx.security.state.SecurityPatchState
import androidx.security.state.SecurityPatchState.DateBasedSecurityPatchLevel
import androidx.security.state.UpdateInfo
import androidx.security.state.provider.UpdateInfoManager
import androidx.security.state.provider.UpdateInfoService
import java.util.concurrent.TimeUnit

class MyUpdateInfoService : UpdateInfoService() {
    // Manage local update records and check timestamps
    private val updateInfoManager by lazy { UpdateInfoManager(this) }

    override suspend fun fetchUpdates(): List<UpdateInfo> {
        val currentSpl = SecurityPatchState(this)
            .getDeviceSecurityPatchLevel(SecurityPatchState.COMPONENT_SYSTEM)

        // 1. Execute network request to OTA backend
        val response = MyOtaBackendClient.checkAvailableUpdates()

        // 2. Defensively filter out blank or non-advancing SPLs and map to UpdateInfo objects
        val validUpdates = response.updates
            .mapNotNull { updateItem ->
                val splString = updateItem.targetSpl?.trim()
                if (splString.isNullOrEmpty()) return@mapNotNull null
                val parsedSpl = DateBasedSecurityPatchLevel.fromString(splString)
                if (parsedSpl > currentSpl) {
                    UpdateInfo.Builder()
                        .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                        .setSecurityPatchLevel(parsedSpl)
                        .setPublishedDateMillis(updateItem.releaseTimestampMillis)
                        .setLastCheckTimeMillis(System.currentTimeMillis())
                        .build()
                } else {
                    null
                }
            }

        // 3. If no advancing SYSTEM update is available (or if a previously offered update was revoked),
        // proactively unregister any cached record for this component.
        if (validUpdates.isEmpty()) {
            val clearTarget = UpdateInfo.Builder()
                .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                .build()
            updateInfoManager.unregisterUpdate(clearTarget)
        }
        return validUpdates
    }

    override fun shouldFetchUpdates(): Boolean {
        // Enforce custom freshness threshold (for example, 4 hours instead of default 1 hour)
        val lastCheckMillis = updateInfoManager.getLastCheckTimeMillis()
        val dataAge = System.currentTimeMillis() - lastCheckMillis
        return dataAge > TimeUnit.HOURS.toMillis(4)
    }
}

package com.example.android.updater;

import android.text.TextUtils;
import androidx.annotation.NonNull;
import androidx.security.state.SecurityPatchState;
import androidx.security.state.SecurityPatchState.DateBasedSecurityPatchLevel;
import androidx.security.state.SecurityPatchState.SecurityPatchLevel;
import androidx.security.state.UpdateInfo;
import androidx.security.state.provider.ListenableFutureUpdateInfoService;
import androidx.security.state.provider.UpdateInfoManager;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;

public class MyUpdateInfoService extends ListenableFutureUpdateInfoService {
    private UpdateInfoManager updateInfoManager;

    @Override
    public void onCreate() {
        super.onCreate();
        // Pass null for customSecurityState because UpdateInfoManager does not declare @JvmOverloads
        updateInfoManager = new UpdateInfoManager(this, /* customSecurityState= */ null);
    }

    @NonNull
    @Override
    protected ListenableFuture<List<UpdateInfo>> fetchUpdatesAsync() {
        try {
            SecurityPatchLevel currentSpl = new SecurityPatchState(this)
                    .getDeviceSecurityPatchLevel(SecurityPatchState.COMPONENT_SYSTEM);
            MyOtaBackendResponse response = MyOtaBackendClient.checkAvailableUpdates();
            List<UpdateInfo> updates = new ArrayList<>();
            for (MyOtaUpdateItem item : response.getUpdates()) {
                String trimmedSpl = (item.getTargetSpl() != null) ? item.getTargetSpl().trim() : null;
                if (!TextUtils.isEmpty(trimmedSpl)) {
                    DateBasedSecurityPatchLevel parsedSpl =
                            DateBasedSecurityPatchLevel.fromString(trimmedSpl);
                    if (parsedSpl.compareTo(currentSpl) > 0) {
                        updates.add(new UpdateInfo.Builder()
                                .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                                .setSecurityPatchLevel(parsedSpl)
                                .setPublishedDateMillis(item.getReleaseTimestampMillis())
                                .setLastCheckTimeMillis(System.currentTimeMillis())
                                .build());
                    }
                }
            }

            // If no advancing SYSTEM update is available (or if a previously offered update was revoked),
            // proactively unregister any cached record for this component.
            if (updates.isEmpty()) {
                UpdateInfo clearTarget = new UpdateInfo.Builder()
                        .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
                        .build();
                updateInfoManager.unregisterUpdate(clearTarget);
            }
            return Futures.immediateFuture(updates);
        } catch (Exception e) {
            return Futures.immediateFailedFuture(e);
        }
    }

    @Override
    protected boolean shouldFetchUpdates() {
        long lastCheckMillis = updateInfoManager.getLastCheckTimeMillis();
        long dataAge = System.currentTimeMillis() - lastCheckMillis;
        return dataAge > TimeUnit.HOURS.toMillis(4);
    }
}

// Build target identifying the component to unregister
val target = UpdateInfo.Builder()
    .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
    .build()
// Unregister the update to remove it from disk cache
updateInfoManager.unregisterUpdate(target)
// Refresh last check timestamp to indicate up-to-date state
updateInfoManager.setLastCheckTimeMillis(System.currentTimeMillis())

// Build target identifying the component to unregister
UpdateInfo target = new UpdateInfo.Builder()
    .setComponent(SecurityPatchState.COMPONENT_SYSTEM)
    .build();
// Unregister the update to remove it from disk cache
updateInfoManager.unregisterUpdate(target);
// Refresh last check timestamp to indicate up-to-date state
updateInfoManager.setLastCheckTimeMillis(System.currentTimeMillis());

import androidx.security.state.provider.UpdateCheckTelemetry
import androidx.security.state.provider.UpdateFetchOutcome
import androidx.security.state.provider.UpdateInfoService

abstract class MonitoredUpdateInfoService : UpdateInfoService() {
    override fun onRequestCompleted(telemetry: UpdateCheckTelemetry) {
        val outcomeName = when (telemetry.outcome) {
            UpdateFetchOutcome.CACHE_HIT -> "CACHE_HIT"
            UpdateFetchOutcome.COALESCED -> "COALESCED"
            UpdateFetchOutcome.FETCHED -> "FETCHED"
            UpdateFetchOutcome.THROTTLED -> "THROTTLED"
            UpdateFetchOutcome.FAILED -> "FAILED"
            else -> "UNKNOWN"
        }
        MyAnalytics.logEvent("SECURITY_UPDATE_CHECK")
            .addParam("outcome", outcomeName)
            .addParam("total_duration_ms", telemetry.totalDurationMillis)
            .addParam("lock_wait_ms", telemetry.lockWaitDurationMillis)
            .addParam("processing_ms", telemetry.processingDurationMillis)
            .addParam("fetch_duration_ms", telemetry.fetchDurationMillis)
            .addParam("caller_uid", telemetry.callerUid)
            .send()
    }

    override fun onClientConnected(packageName: String, callerUid: Int) {
        // Track authenticated client sessions and adoption
        MyMetrics.incrementCounter("client_connected", "package", packageName)
    }

    override fun onClientDisconnected(packageName: String, callerUid: Int) {
        // Track session termination and cleanup resources
        MyMetrics.incrementCounter("client_disconnected", "package", packageName)
    }

    override fun onFetchFailed(e: Exception) {
        // Report exceptions caught during the update check workflow
        MyCrashReporter.recordException(e)
    }
}

import androidx.annotation.NonNull;
import androidx.security.state.provider.ListenableFutureUpdateInfoService;
import androidx.security.state.provider.UpdateCheckTelemetry;
import androidx.security.state.provider.UpdateFetchOutcome;

public abstract class MonitoredUpdateInfoService extends ListenableFutureUpdateInfoService {
    @Override
    protected void onRequestCompleted(@NonNull UpdateCheckTelemetry telemetry) {
        String outcomeName;
        switch (telemetry.getOutcome()) {
            case UpdateFetchOutcome.CACHE_HIT: outcomeName = "CACHE_HIT"; break;
            case UpdateFetchOutcome.COALESCED: outcomeName = "COALESCED"; break;
            case UpdateFetchOutcome.FETCHED: outcomeName = "FETCHED"; break;
            case UpdateFetchOutcome.THROTTLED: outcomeName = "THROTTLED"; break;
            case UpdateFetchOutcome.FAILED: outcomeName = "FAILED"; break;
            default: outcomeName = "UNKNOWN"; break;
        }
        MyAnalytics.logEvent("SECURITY_UPDATE_CHECK")
            .addParam("outcome", outcomeName)
            .addParam("total_duration_ms", telemetry.getTotalDurationMillis())
            .addParam("lock_wait_ms", telemetry.getLockWaitDurationMillis())
            .addParam("processing_ms", telemetry.getProcessingDurationMillis())
            .addParam("fetch_duration_ms", telemetry.getFetchDurationMillis())
            .addParam("caller_uid", telemetry.getCallerUid())
            .send();
    }

    @Override
    protected void onClientConnected(@NonNull String packageName, int callerUid) {
        MyMetrics.incrementCounter("client_connected", "package", packageName);
    }

    @Override
    protected void onClientDisconnected(@NonNull String packageName, int callerUid) {
        MyMetrics.incrementCounter("client_disconnected", "package", packageName);
    }

    @Override
    protected void onFetchFailed(@NonNull Exception e) {
        MyCrashReporter.recordException(e);
    }
}