Add download request tokens and enforce destination clear (8763c625) · Commits · e / os / android_frameworks_base

telephony/java/android/telephony/MbmsDownloadManager.java

+54 −14

Original line number	Diff line number	Diff line
		@@ -388,21 +388,10 @@ public class MbmsDownloadManager {
		tempRootDirectory.mkdirs();
		setTempFileRootDirectory(tempRootDirectory);
		}

		request.setAppName(mDownloadAppName);
		// Check if the request is a multipart download. If so, validate that the destination is
		// a directory that exists.
		// TODO: figure out what qualifies a request as a multipart download request.
		if (request.getSourceUri().getLastPathSegment() != null &&
		request.getSourceUri().getLastPathSegment().contains("*")) {
		File toFile = new File(request.getDestinationUri().getSchemeSpecificPart());
		if (!toFile.isDirectory()) {
		throw new IllegalArgumentException("Multipart download must specify valid " +
		"destination directory.");
		}
		}
		// TODO: check to make sure destination is clear
		// TODO: write download request token

		checkValidDownloadDestination(request);
		writeDownloadRequestToken(request);
		try {
		downloadService.download(request, callback);
		} catch (RemoteException e) {
		@@ -435,6 +424,7 @@ public class MbmsDownloadManager {
		* <li>ERROR_MSDC_UNKNOWN_REQUEST</li>
		*/
		public int cancelDownload(DownloadRequest downloadRequest) {
		// TODO: don't forget to delete the token
		return 0;
		}

		@@ -518,4 +508,54 @@ public class MbmsDownloadManager {
		Log.i(LOG_TAG, "Remote exception while disposing of service");
		}
		}

		private void writeDownloadRequestToken(DownloadRequest request) {
		// TODO: figure out when this token eventually gets deleted
		File tempFileLocation = MbmsUtils.getEmbmsTempFileDirForRequest(mContext, request);
		if (!tempFileLocation.exists()) {
		tempFileLocation.mkdirs();
		}
		String downloadTokenFileName = request.getHash()
		+ MbmsDownloadReceiver.DOWNLOAD_TOKEN_SUFFIX;
		File token = new File(tempFileLocation, downloadTokenFileName);
		if (token.exists()) {
		Log.w(LOG_TAG, "Download token " + downloadTokenFileName + " already exists");
		return;
		}
		try {
		if (!token.createNewFile()) {
		throw new RuntimeException("Failed to create download token for request "
		+ request);
		}
		} catch (IOException e) {
		throw new RuntimeException("Failed to create download token for request " + request
		+ " due to IOException " + e);
		}
		}

		/**
		* Verifies the following:
		* If a request is multi-part,
		* 1. Destination Uri must exist and be a directory
		* 2. Directory specified must contain no files.
		* Otherwise
		* 1. The file specified by the destination Uri must not exist.
		*/
		private void checkValidDownloadDestination(DownloadRequest request) {
		File toFile = new File(request.getDestinationUri().getSchemeSpecificPart());
		if (request.isMultipartDownload()) {
		if (!toFile.isDirectory()) {
		throw new IllegalArgumentException("Multipart download must specify valid " +
		"destination directory.");
		}
		if (toFile.listFiles().length > 0) {
		throw new IllegalArgumentException("Destination directory must be clear of all " +
		"files.");
		}
		} else {
		if (toFile.exists()) {
		throw new IllegalArgumentException("Destination file must not exist.");
		}
		}
		}
		}

telephony/java/android/telephony/mbms/DownloadRequest.java

+55 −2

Original line number	Diff line number	Diff line
		@@ -20,15 +20,22 @@ import android.content.Intent;
		import android.net.Uri;
		import android.os.Parcel;
		import android.os.Parcelable;
		import android.util.Base64;

		import java.lang.IllegalStateException;
		import java.net.URISyntaxException;
		import java.nio.charset.StandardCharsets;
		import java.security.MessageDigest;
		import java.security.NoSuchAlgorithmException;

		/**
		* A Parcelable class describing a pending Cell-Broadcast download request
		* @hide
		*/
		public class DownloadRequest implements Parcelable {
		// Version code used to keep token calculation consistent.
		private static final int CURRENT_VERSION = 1;

		/** @hide */
		public static class Builder {
		private int id;
		@@ -37,6 +44,7 @@ public class DownloadRequest implements Parcelable {
		private Uri dest;
		private int subscriptionId;
		private String appIntent;
		private int version = CURRENT_VERSION;

		public Builder setId(int id) {
		this.id = id;
		@@ -68,9 +76,14 @@ public class DownloadRequest implements Parcelable {
		return this;
		}

		public Builder setVersion(int version) {
		this.version = version;
		return this;
		}

		public DownloadRequest build() {
		return new DownloadRequest(id, serviceInfo, source, dest,
		subscriptionId, appIntent, null);
		subscriptionId, appIntent, null, version);
		}
		}

		@@ -80,11 +93,12 @@ public class DownloadRequest implements Parcelable {
		private final Uri destinationUri;
		private final int subscriptionId;
		private final String serializedResultIntentForApp;
		private final int version;
		private String appName; // not the Android app Name, the embms app name

		private DownloadRequest(int id, FileServiceInfo serviceInfo,
		Uri source, Uri dest,
		int sub, String appIntent, String name) {
		int sub, String appIntent, String name, int version) {
		downloadId = id;
		fileServiceInfo = serviceInfo;
		sourceUri = source;
		@@ -92,6 +106,7 @@ public class DownloadRequest implements Parcelable {
		subscriptionId = sub;
		serializedResultIntentForApp = appIntent;
		appName = name;
		this.version = version;
		}

		public static DownloadRequest copy(DownloadRequest other) {
		@@ -106,6 +121,7 @@ public class DownloadRequest implements Parcelable {
		subscriptionId = dr.subscriptionId;
		serializedResultIntentForApp = dr.serializedResultIntentForApp;
		appName = dr.appName;
		version = dr.version;
		}

		private DownloadRequest(Parcel in) {
		@@ -116,6 +132,7 @@ public class DownloadRequest implements Parcelable {
		subscriptionId = in.readInt();
		serializedResultIntentForApp = in.readString();
		appName = in.readString();
		version = in.readInt();
		}

		public int describeContents() {
		@@ -130,6 +147,7 @@ public class DownloadRequest implements Parcelable {
		out.writeInt(subscriptionId);
		out.writeString(serializedResultIntentForApp);
		out.writeString(appName);
		out.writeInt(version);
		}

		public int getDownloadId() {
		@@ -172,6 +190,10 @@ public class DownloadRequest implements Parcelable {
		return appName;
		}

		public int getVersion() {
		return version;
		}

		public static final Parcelable.Creator<DownloadRequest> CREATOR =
		new Parcelable.Creator<DownloadRequest>() {
		public DownloadRequest createFromParcel(Parcel in) {
		@@ -181,4 +203,35 @@ public class DownloadRequest implements Parcelable {
		return new DownloadRequest[size];
		}
		};

		/**
		* @hide
		*/
		public boolean isMultipartDownload() {
		// TODO: figure out what qualifies a request as a multipart download request.
		return getSourceUri().getLastPathSegment() != null &&
		getSourceUri().getLastPathSegment().contains("*");
		}

		/**
		* Retrieves the hash string that should be used as the filename when storing a token for
		* this DownloadRequest.
		* @hide
		*/
		public String getHash() {
		MessageDigest digest;
		try {
		digest = MessageDigest.getInstance("SHA-256");
		} catch (NoSuchAlgorithmException e) {
		throw new RuntimeException("Could not get sha256 hash object");
		}
		if (version >= 1) {
		// Hash the source URI, destination URI, and the app intent
		digest.update(sourceUri.toString().getBytes(StandardCharsets.UTF_8));
		digest.update(destinationUri.toString().getBytes(StandardCharsets.UTF_8));
		digest.update(serializedResultIntentForApp.getBytes(StandardCharsets.UTF_8));
		}
		// Add updates for future versions here
		return Base64.encodeToString(digest.digest(), Base64.URL_SAFE \| Base64.NO_WRAP);
		}
		}

telephony/java/android/telephony/mbms/MbmsDownloadReceiver.java

+17 −17

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@ import java.util.UUID;
		public class MbmsDownloadReceiver extends BroadcastReceiver {
		private static final String LOG_TAG = "MbmsDownloadReceiver";
		private static final String TEMP_FILE_SUFFIX = ".embms.temp";
		public static final String DOWNLOAD_TOKEN_SUFFIX = ".download_token";
		private static final int MAX_TEMP_FILE_RETRIES = 5;

		public static final String MBMS_FILE_PROVIDER_META_DATA_KEY = "mbms-file-provider-authority";
		@@ -50,7 +51,7 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {

		@Override
		public void onReceive(Context context, Intent intent) {
		if (!verifyIntentContents(intent)) {
		if (!verifyIntentContents(context, intent)) {
		setResultCode(1 /* TODO: define error constants */);
		return;
		}
		@@ -69,7 +70,7 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {
		// TODO: Add handling for ACTION_CLEANUP
		}

		private boolean verifyIntentContents(Intent intent) {
		private boolean verifyIntentContents(Context context, Intent intent) {
		if (MbmsDownloadManager.ACTION_DOWNLOAD_RESULT_INTERNAL.equals(intent.getAction())) {
		if (!intent.hasExtra(MbmsDownloadManager.EXTRA_RESULT)) {
		Log.w(LOG_TAG, "Download result did not include a result code. Ignoring.");
		@@ -93,8 +94,19 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {
		"temp file. Ignoring.");
		return false;
		}
		DownloadRequest request = intent.getParcelableExtra(MbmsDownloadManager.EXTRA_REQUEST);
		String expectedTokenFileName = request.getHash() + DOWNLOAD_TOKEN_SUFFIX;
		File expectedTokenFile = new File(
		MbmsUtils.getEmbmsTempFileDirForRequest(context, request),
		expectedTokenFileName);
		if (!expectedTokenFile.exists()) {
		Log.w(LOG_TAG, "Supplied download request does not match a token that we have. " +
		"Expected " + expectedTokenFile);
		return false;
		}
		return true;
		} else if (MbmsDownloadManager.ACTION_FILE_DESCRIPTOR_REQUEST.equals(intent.getAction())) {
		// TODO: get rid of the request argument for a file descriptor request.
		if (!intent.hasExtra(MbmsDownloadManager.EXTRA_REQUEST)) {
		Log.w(LOG_TAG, "Temp file request not include the associated request. Ignoring.");
		return false;
		@@ -112,7 +124,6 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {

		private void moveDownloadedFile(Context context, Intent intent) {
		DownloadRequest request = intent.getParcelableExtra(MbmsDownloadManager.EXTRA_REQUEST);
		// TODO: check request against token
		Intent intentForApp = request.getIntentForApp();

		int result = intent.getIntExtra(MbmsDownloadManager.EXTRA_RESULT,
		@@ -149,7 +160,6 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {
		}

		private void cleanupPostMove(Context context, Intent intent) {
		// TODO: account for in-use temp files
		DownloadRequest request = intent.getParcelableExtra(MbmsDownloadManager.EXTRA_REQUEST);
		if (request == null) {
		Log.w(LOG_TAG, "Intent does not include a DownloadRequest. Ignoring.");
		@@ -199,7 +209,7 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {

		private ArrayList<UriPathPair> generateFreshTempFiles(Context context, DownloadRequest request,
		int freshFdCount) {
		File tempFileDir = getEmbmsTempFileDirForRequest(context, request);
		File tempFileDir = MbmsUtils.getEmbmsTempFileDirForRequest(context, request);
		if (!tempFileDir.exists()) {
		tempFileDir.mkdirs();
		}
		@@ -345,24 +355,14 @@ public class MbmsDownloadReceiver extends BroadcastReceiver {
		return false;
		}

		if (!MbmsUtils.isContainedIn(getEmbmsTempFileDirForRequest(context, request), tempFile)) {
		if (!MbmsUtils.isContainedIn(
		MbmsUtils.getEmbmsTempFileDirForRequest(context, request), tempFile)) {
		return false;
		}

		return true;
		}

		/**
		* Returns a File linked to the directory used to store temp files for this request
		*/
		private static File getEmbmsTempFileDirForRequest(Context context, DownloadRequest request) {
		File embmsTempFileDir = MbmsTempFileProvider.getEmbmsTempFileDir(context);

		// TODO: better naming scheme for temp file dirs
		String tempFileDirName = String.valueOf(request.getFileServiceInfo().getServiceId());
		return new File(embmsTempFileDir, tempFileDirName);
		}

		private String getFileProviderAuthorityCached(Context context) {
		if (mFileProviderAuthorityCache != null) {
		return mFileProviderAuthorityCache;

telephony/java/android/telephony/mbms/MbmsUtils.java

+10 −0

Original line number	Diff line number	Diff line
		@@ -85,4 +85,14 @@ public class MbmsUtils {

		context.bindService(bindIntent, serviceConnection, Context.BIND_AUTO_CREATE);
		}

		/**
		* Returns a File linked to the directory used to store temp files for this request
		*/
		public static File getEmbmsTempFileDirForRequest(Context context, DownloadRequest request) {
		File embmsTempFileDir = MbmsTempFileProvider.getEmbmsTempFileDir(context);

		String tempFileDirName = String.valueOf(request.getFileServiceInfo().getServiceId());
		return new File(embmsTempFileDir, tempFileDirName);
		}
		}