/* * Copyright (C) 2011 The Android Open Source Project * * 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.nfc; import android.app.ActivityManager; import android.bluetooth.BluetoothAdapter; import android.os.UserManager; import com.android.nfc.RegisteredComponentCache.ComponentInfo; import com.android.nfc.handover.HandoverDataParser; import com.android.nfc.handover.PeripheralHandoverService; import android.app.Activity; import android.app.ActivityManager; import android.app.ActivityManagerNative; import android.app.IActivityManager; import android.app.PendingIntent; import android.app.PendingIntent.CanceledException; import android.content.ComponentName; import android.content.ContentResolver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.pm.PackageManager; import android.content.pm.PackageManager.NameNotFoundException; import android.content.pm.ResolveInfo; import android.content.res.Resources.NotFoundException; import android.net.Uri; import android.nfc.NdefMessage; import android.nfc.NdefRecord; import android.nfc.NfcAdapter; import android.nfc.Tag; import android.nfc.tech.Ndef; import android.nfc.tech.NfcBarcode; import android.os.RemoteException; import android.os.UserHandle; import android.util.Log; import java.io.FileDescriptor; import java.io.PrintWriter; import java.nio.charset.StandardCharsets; import java.util.ArrayList; import java.util.Arrays; import java.util.LinkedList; import java.util.List; /** * Dispatch of NFC events to start activities */ class NfcDispatcher { private static final boolean DBG = false; private static final String TAG = "NfcDispatcher"; static final int DISPATCH_SUCCESS = 1; static final int DISPATCH_FAIL = 2; static final int DISPATCH_UNLOCK = 3; private final Context mContext; private final IActivityManager mIActivityManager; private final RegisteredComponentCache mTechListFilters; private final ContentResolver mContentResolver; private final HandoverDataParser mHandoverDataParser; private final String[] mProvisioningMimes; private final ScreenStateHelper mScreenStateHelper; private final NfcUnlockManager mNfcUnlockManager; private final boolean mDeviceSupportsBluetooth; // Locked on this private PendingIntent mOverrideIntent; private IntentFilter[] mOverrideFilters; private String[][] mOverrideTechLists; private boolean mProvisioningOnly; NfcDispatcher(Context context, HandoverDataParser handoverDataParser, boolean provisionOnly) { mContext = context; mIActivityManager = ActivityManagerNative.getDefault(); mTechListFilters = new RegisteredComponentCache(mContext, NfcAdapter.ACTION_TECH_DISCOVERED, NfcAdapter.ACTION_TECH_DISCOVERED); mContentResolver = context.getContentResolver(); mHandoverDataParser = handoverDataParser; mScreenStateHelper = new ScreenStateHelper(context); mNfcUnlockManager = NfcUnlockManager.getInstance(); mDeviceSupportsBluetooth = BluetoothAdapter.getDefaultAdapter() != null; synchronized (this) { mProvisioningOnly = provisionOnly; } String[] provisionMimes = null; if (provisionOnly) { try { // Get accepted mime-types provisionMimes = context.getResources(). getStringArray(R.array.provisioning_mime_types); } catch (NotFoundException e) { provisionMimes = null; } } mProvisioningMimes = provisionMimes; } public synchronized void setForegroundDispatch(PendingIntent intent, IntentFilter[] filters, String[][] techLists) { if (DBG) Log.d(TAG, "Set Foreground Dispatch"); mOverrideIntent = intent; mOverrideFilters = filters; mOverrideTechLists = techLists; } public synchronized void disableProvisioningMode() { mProvisioningOnly = false; } /** * Helper for re-used objects and methods during a single tag dispatch. */ static class DispatchInfo { public final Intent intent; final Intent rootIntent; final Uri ndefUri; final String ndefMimeType; final PackageManager packageManager; final Context context; public DispatchInfo(Context context, Tag tag, NdefMessage message) { intent = new Intent(); intent.putExtra(NfcAdapter.EXTRA_TAG, tag); intent.putExtra(NfcAdapter.EXTRA_ID, tag.getId()); if (message != null) { intent.putExtra(NfcAdapter.EXTRA_NDEF_MESSAGES, new NdefMessage[] {message}); ndefUri = message.getRecords()[0].toUri(); ndefMimeType = message.getRecords()[0].toMimeType(); } else { ndefUri = null; ndefMimeType = null; } rootIntent = new Intent(context, NfcRootActivity.class); rootIntent.putExtra(NfcRootActivity.EXTRA_LAUNCH_INTENT, intent); rootIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK); this.context = context; packageManager = context.getPackageManager(); } public Intent setNdefIntent() { intent.setAction(NfcAdapter.ACTION_NDEF_DISCOVERED); if (ndefUri != null) { intent.setData(ndefUri); return intent; } else if (ndefMimeType != null) { intent.setType(ndefMimeType); return intent; } return null; } public Intent setTechIntent() { intent.setData(null); intent.setType(null); intent.setAction(NfcAdapter.ACTION_TECH_DISCOVERED); return intent; } public Intent setTagIntent() { intent.setData(null); intent.setType(null); intent.setAction(NfcAdapter.ACTION_TAG_DISCOVERED); return intent; } /** * Launch the activity via a (single) NFC root task, so that it * creates a new task stack instead of interfering with any existing * task stack for that activity. * NfcRootActivity acts as the task root, it immediately calls * start activity on the intent it is passed. */ boolean tryStartActivity() { // Ideally we'd have used startActivityForResult() to determine whether the // NfcRootActivity was able to launch the intent, but startActivityForResult() // is not available on Context. Instead, we query the PackageManager beforehand // to determine if there is an Activity to handle this intent, and base the // result of off that. List activities = packageManager.queryIntentActivitiesAsUser(intent, 0, ActivityManager.getCurrentUser()); if (activities.size() > 0) { context.startActivityAsUser(rootIntent, UserHandle.CURRENT); return true; } return false; } boolean tryStartActivity(Intent intentToStart) { List activities = packageManager.queryIntentActivitiesAsUser( intentToStart, 0, ActivityManager.getCurrentUser()); if (activities.size() > 0) { rootIntent.putExtra(NfcRootActivity.EXTRA_LAUNCH_INTENT, intentToStart); context.startActivityAsUser(rootIntent, UserHandle.CURRENT); return true; } return false; } } /** Returns: * */ public int dispatchTag(Tag tag) { PendingIntent overrideIntent; IntentFilter[] overrideFilters; String[][] overrideTechLists; String[] provisioningMimes; boolean provisioningOnly; synchronized (this) { overrideFilters = mOverrideFilters; overrideIntent = mOverrideIntent; overrideTechLists = mOverrideTechLists; provisioningOnly = mProvisioningOnly; provisioningMimes = mProvisioningMimes; } boolean screenUnlocked = false; if (!provisioningOnly && mScreenStateHelper.checkScreenState() == ScreenStateHelper.SCREEN_STATE_ON_LOCKED) { screenUnlocked = handleNfcUnlock(tag); if (!screenUnlocked) { return DISPATCH_FAIL; } } NdefMessage message = null; Ndef ndef = Ndef.get(tag); if (ndef != null) { message = ndef.getCachedNdefMessage(); } else { NfcBarcode nfcBarcode = NfcBarcode.get(tag); if (nfcBarcode != null && nfcBarcode.getType() == NfcBarcode.TYPE_KOVIO) { message = decodeNfcBarcodeUri(nfcBarcode); } } if (DBG) Log.d(TAG, "dispatch tag: " + tag.toString() + " message: " + message); DispatchInfo dispatch = new DispatchInfo(mContext, tag, message); resumeAppSwitches(); if (tryOverrides(dispatch, tag, message, overrideIntent, overrideFilters, overrideTechLists)) { return screenUnlocked ? DISPATCH_UNLOCK : DISPATCH_SUCCESS; } if (tryPeripheralHandover(message)) { if (DBG) Log.i(TAG, "matched BT HANDOVER"); return screenUnlocked ? DISPATCH_UNLOCK : DISPATCH_SUCCESS; } if (NfcWifiProtectedSetup.tryNfcWifiSetup(ndef, mContext)) { if (DBG) Log.i(TAG, "matched NFC WPS TOKEN"); return screenUnlocked ? DISPATCH_UNLOCK : DISPATCH_SUCCESS; } if (provisioningOnly) { if (message == null) { // We only allow NDEF-message dispatch in provisioning mode return DISPATCH_FAIL; } // Restrict to mime-types in whitelist. String ndefMimeType = message.getRecords()[0].toMimeType(); if (provisioningMimes == null || !(Arrays.asList(provisioningMimes).contains(ndefMimeType))) { Log.e(TAG, "Dropping NFC intent in provisioning mode."); return DISPATCH_FAIL; } } if (tryNdef(dispatch, message)) { return screenUnlocked ? DISPATCH_UNLOCK : DISPATCH_SUCCESS; } if (screenUnlocked) { // We only allow NDEF-based mimeType matching in case of an unlock return DISPATCH_UNLOCK; } // Only allow NDEF-based mimeType matching for unlock tags if (tryTech(dispatch, tag)) { return DISPATCH_SUCCESS; } dispatch.setTagIntent(); if (dispatch.tryStartActivity()) { if (DBG) Log.i(TAG, "matched TAG"); return DISPATCH_SUCCESS; } if (DBG) Log.i(TAG, "no match"); return DISPATCH_FAIL; } private boolean handleNfcUnlock(Tag tag) { return mNfcUnlockManager.tryUnlock(tag); } /** * Checks for the presence of a URL stored in a tag with tech NfcBarcode. * If found, decodes URL and returns NdefMessage message containing an * NdefRecord containing the decoded URL. If not found, returns null. * * URLs are decoded as follows: * * Ignore first byte (which is 0x80 ORd with a manufacturer ID, corresponding * to ISO/IEC 7816-6). * The second byte describes the payload data format. There are four defined data * format values that identify URL data. Depending on the data format value, the * associated prefix is appended to the URL data: * * 0x01: URL with "http://www." prefix * 0x02: URL with "https://www." prefix * 0x03: URL with "http://" prefix * 0x04: URL with "https://" prefix * * Other data format values do not identify URL data and are not handled by this function. * URL payload is encoded in US-ASCII, following the limitations defined in RFC3987. * see http://www.ietf.org/rfc/rfc3987.txt * * The final two bytes of a tag with tech NfcBarcode are always reserved for CRC data, * and are therefore not part of the payload. They are ignored in the decoding of a URL. * * The default assumption is that the URL occupies the entire payload of the NfcBarcode * ID and all bytes of the NfcBarcode payload are decoded until the CRC (final two bytes) * is reached. However, the OPTIONAL early terminator byte 0xfe can be used to signal * an early end of the URL. Once this function reaches an early terminator byte 0xfe, * URL decoding stops and the NdefMessage is created and returned. Any payload data after * the first early terminator byte is ignored for the purposes of URL decoding. */ private NdefMessage decodeNfcBarcodeUri(NfcBarcode nfcBarcode) { final byte URI_PREFIX_HTTP_WWW = (byte) 0x01; // "http://www." final byte URI_PREFIX_HTTPS_WWW = (byte) 0x02; // "https://www." final byte URI_PREFIX_HTTP = (byte) 0x03; // "http://" final byte URI_PREFIX_HTTPS = (byte) 0x04; // "https://" NdefMessage message = null; byte[] tagId = nfcBarcode.getTag().getId(); // All tags of NfcBarcode technology and Kovio type have lengths of a multiple of 16 bytes if (tagId.length >= 4 && (tagId[1] == URI_PREFIX_HTTP_WWW || tagId[1] == URI_PREFIX_HTTPS_WWW || tagId[1] == URI_PREFIX_HTTP || tagId[1] == URI_PREFIX_HTTPS)) { // Look for optional URI terminator (0xfe), used to indicate the end of a URI prior to // the end of the full NfcBarcode payload. No terminator means that the URI occupies the // entire length of the payload field. Exclude checking the CRC in the final two bytes // of the NfcBarcode tagId. int end = 2; for (; end < tagId.length - 2; end++) { if (tagId[end] == (byte) 0xfe) { break; } } byte[] payload = new byte[end - 1]; // Skip also first byte (manufacturer ID) System.arraycopy(tagId, 1, payload, 0, payload.length); NdefRecord uriRecord = new NdefRecord( NdefRecord.TNF_WELL_KNOWN, NdefRecord.RTD_URI, tagId, payload); message = new NdefMessage(uriRecord); } return message; } boolean tryOverrides(DispatchInfo dispatch, Tag tag, NdefMessage message, PendingIntent overrideIntent, IntentFilter[] overrideFilters, String[][] overrideTechLists) { if (overrideIntent == null) { return false; } Intent intent; // NDEF if (message != null) { intent = dispatch.setNdefIntent(); if (intent != null && isFilterMatch(intent, overrideFilters, overrideTechLists != null)) { try { overrideIntent.send(mContext, Activity.RESULT_OK, intent); if (DBG) Log.i(TAG, "matched NDEF override"); return true; } catch (CanceledException e) { return false; } } } // TECH intent = dispatch.setTechIntent(); if (isTechMatch(tag, overrideTechLists)) { try { overrideIntent.send(mContext, Activity.RESULT_OK, intent); if (DBG) Log.i(TAG, "matched TECH override"); return true; } catch (CanceledException e) { return false; } } // TAG intent = dispatch.setTagIntent(); if (isFilterMatch(intent, overrideFilters, overrideTechLists != null)) { try { overrideIntent.send(mContext, Activity.RESULT_OK, intent); if (DBG) Log.i(TAG, "matched TAG override"); return true; } catch (CanceledException e) { return false; } } return false; } boolean isFilterMatch(Intent intent, IntentFilter[] filters, boolean hasTechFilter) { if (filters != null) { for (IntentFilter filter : filters) { if (filter.match(mContentResolver, intent, false, TAG) >= 0) { return true; } } } else if (!hasTechFilter) { return true; // always match if both filters and techlists are null } return false; } boolean isTechMatch(Tag tag, String[][] techLists) { if (techLists == null) { return false; } String[] tagTechs = tag.getTechList(); Arrays.sort(tagTechs); for (String[] filterTechs : techLists) { if (filterMatch(tagTechs, filterTechs)) { return true; } } return false; } boolean tryNdef(DispatchInfo dispatch, NdefMessage message) { if (message == null) { return false; } Intent intent = dispatch.setNdefIntent(); // Bail out if the intent does not contain filterable NDEF data if (intent == null) return false; // Try to start AAR activity with matching filter List aarPackages = extractAarPackages(message); for (String pkg : aarPackages) { dispatch.intent.setPackage(pkg); if (dispatch.tryStartActivity()) { if (DBG) Log.i(TAG, "matched AAR to NDEF"); return true; } } // Try to perform regular launch of the first AAR if (aarPackages.size() > 0) { String firstPackage = aarPackages.get(0); PackageManager pm; try { UserHandle currentUser = new UserHandle(ActivityManager.getCurrentUser()); pm = mContext.createPackageContextAsUser("android", 0, currentUser).getPackageManager(); } catch (NameNotFoundException e) { Log.e(TAG, "Could not create user package context"); return false; } Intent appLaunchIntent = pm.getLaunchIntentForPackage(firstPackage); if (appLaunchIntent != null && dispatch.tryStartActivity(appLaunchIntent)) { if (DBG) Log.i(TAG, "matched AAR to application launch"); return true; } // Find the package in Market: Intent marketIntent = getAppSearchIntent(firstPackage); if (marketIntent != null && dispatch.tryStartActivity(marketIntent)) { if (DBG) Log.i(TAG, "matched AAR to market launch"); return true; } } // regular launch dispatch.intent.setPackage(null); if (dispatch.tryStartActivity()) { if (DBG) Log.i(TAG, "matched NDEF"); return true; } return false; } static List extractAarPackages(NdefMessage message) { List aarPackages = new LinkedList(); for (NdefRecord record : message.getRecords()) { String pkg = checkForAar(record); if (pkg != null) { aarPackages.add(pkg); } } return aarPackages; } boolean tryTech(DispatchInfo dispatch, Tag tag) { dispatch.setTechIntent(); String[] tagTechs = tag.getTechList(); Arrays.sort(tagTechs); // Standard tech dispatch path ArrayList matches = new ArrayList(); List registered = mTechListFilters.getComponents(); PackageManager pm; try { UserHandle currentUser = new UserHandle(ActivityManager.getCurrentUser()); pm = mContext.createPackageContextAsUser("android", 0, currentUser).getPackageManager(); } catch (NameNotFoundException e) { Log.e(TAG, "Could not create user package context"); return false; } // Check each registered activity to see if it matches for (ComponentInfo info : registered) { // Don't allow wild card matching if (filterMatch(tagTechs, info.techs) && isComponentEnabled(pm, info.resolveInfo)) { // Add the activity as a match if it's not already in the list if (!matches.contains(info.resolveInfo)) { matches.add(info.resolveInfo); } } } if (matches.size() == 1) { // Single match, launch directly ResolveInfo info = matches.get(0); dispatch.intent.setClassName(info.activityInfo.packageName, info.activityInfo.name); if (dispatch.tryStartActivity()) { if (DBG) Log.i(TAG, "matched single TECH"); return true; } dispatch.intent.setComponent(null); } else if (matches.size() > 1) { // Multiple matches, show a custom activity chooser dialog Intent intent = new Intent(mContext, TechListChooserActivity.class); intent.putExtra(Intent.EXTRA_INTENT, dispatch.intent); intent.putParcelableArrayListExtra(TechListChooserActivity.EXTRA_RESOLVE_INFOS, matches); if (dispatch.tryStartActivity(intent)) { if (DBG) Log.i(TAG, "matched multiple TECH"); return true; } } return false; } public boolean tryPeripheralHandover(NdefMessage m) { if (m == null || !mDeviceSupportsBluetooth) return false; if (DBG) Log.d(TAG, "tryHandover(): " + m.toString()); HandoverDataParser.BluetoothHandoverData handover = mHandoverDataParser.parseBluetooth(m); if (handover == null || !handover.valid) return false; if (UserManager.get(mContext).hasUserRestriction( UserManager.DISALLOW_CONFIG_BLUETOOTH, // hasUserRestriction does not support UserHandle.CURRENT UserHandle.of(ActivityManager.getCurrentUser()))) { return false; } Intent intent = new Intent(mContext, PeripheralHandoverService.class); intent.putExtra(PeripheralHandoverService.EXTRA_PERIPHERAL_DEVICE, handover.device); intent.putExtra(PeripheralHandoverService.EXTRA_PERIPHERAL_NAME, handover.name); intent.putExtra(PeripheralHandoverService.EXTRA_PERIPHERAL_TRANSPORT, handover.transport); if (handover.oobData != null) { intent.putExtra(PeripheralHandoverService.EXTRA_PERIPHERAL_OOB_DATA, handover.oobData); } mContext.startServiceAsUser(intent, UserHandle.CURRENT); return true; } /** * Tells the ActivityManager to resume allowing app switches. * * If the current app called stopAppSwitches() then our startActivity() can * be delayed for several seconds. This happens with the default home * screen. As a system service we can override this behavior with * resumeAppSwitches(). */ void resumeAppSwitches() { try { mIActivityManager.resumeAppSwitches(); } catch (RemoteException e) { } } /** Returns true if the tech list filter matches the techs on the tag */ boolean filterMatch(String[] tagTechs, String[] filterTechs) { if (filterTechs == null || filterTechs.length == 0) return false; for (String tech : filterTechs) { if (Arrays.binarySearch(tagTechs, tech) < 0) { return false; } } return true; } static String checkForAar(NdefRecord record) { if (record.getTnf() == NdefRecord.TNF_EXTERNAL_TYPE && Arrays.equals(record.getType(), NdefRecord.RTD_ANDROID_APP)) { return new String(record.getPayload(), StandardCharsets.US_ASCII); } return null; } /** * Returns an intent that can be used to find an application not currently * installed on the device. */ static Intent getAppSearchIntent(String pkg) { Intent market = new Intent(Intent.ACTION_VIEW); market.setData(Uri.parse("market://details?id=" + pkg)); return market; } static boolean isComponentEnabled(PackageManager pm, ResolveInfo info) { boolean enabled = false; ComponentName compname = new ComponentName( info.activityInfo.packageName, info.activityInfo.name); try { // Note that getActivityInfo() will internally call // isEnabledLP() to determine whether the component // enabled. If it's not, null is returned. if (pm.getActivityInfo(compname,0) != null) { enabled = true; } } catch (PackageManager.NameNotFoundException e) { enabled = false; } if (!enabled) { Log.d(TAG, "Component not enabled: " + compname); } return enabled; } void dump(FileDescriptor fd, PrintWriter pw, String[] args) { synchronized (this) { pw.println("mOverrideIntent=" + mOverrideIntent); pw.println("mOverrideFilters=" + mOverrideFilters); pw.println("mOverrideTechLists=" + mOverrideTechLists); } } }