Develop Reference

App Intent Problem | Your app contains an Intent Redirection vulnerability

I got this message after updating app in play console. I am sharing code of a method where the error is, as suggested by Google. I never updated this part of the code and it never showed any problem before. I am not sure why it is showing me an error. Do I need to update the way of saving a file? I hope to find a solution here.
public void saveDocument(ScannedDocument scannedDocument) {
Mat doc = (scannedDocument.processed != null) ? scannedDocument.processed : scannedDocument.original;
Intent intent = getIntent();
String fileName;
boolean isIntent = false;
Uri fileUri = null;
if (intent.getAction().equals("android.media.action.IMAGE_CAPTURE")) {
fileUri = ((Uri) intent.getParcelableExtra(MediaStore.EXTRA_OUTPUT));
Log.d(TAG, "intent uri: " + fileUri.toString());
try {
fileName = File.createTempFile("onsFile", ".jpg", this.getCacheDir()).getPath();
} catch (IOException e) {
e.printStackTrace();
return;
}
isIntent = true;
} else {
String folderName = mSharedPref.getString("storage_folder", FOLDER_NAME);
File folder = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM).toString()
+ "/" + folderName);
if (!folder.exists()) {
folder.mkdirs();
Log.d(TAG, "wrote: created folder " + folder.getPath());
}
fileName = folder.getAbsolutePath()
+ "/DOC-"
+ new SimpleDateFormat("yyyyMMdd-HHmmss").format(new Date())
+ ".jpg";
}
Mat endDoc = new Mat(Double.valueOf(doc.size().width).intValue(),
Double.valueOf(doc.size().height).intValue(), CvType.CV_8UC4);
Core.flip(doc.t(), endDoc, 1);
Imgcodecs.imwrite(fileName, endDoc);
endDoc.release();
try {
ExifInterface exif = new ExifInterface(fileName);
exif.setAttribute("UserComment", "Generated");
String nowFormatted = mDateFormat.format(new Date().getTime());
exif.setAttribute(ExifInterface.TAG_DATETIME, nowFormatted);
exif.setAttribute(ExifInterface.TAG_DATETIME_DIGITIZED, nowFormatted);
// exif.setAttribute("Software", "OpenNoteScanner " + BuildConfig.VERSION_NAME + "");
exif.saveAttributes();
} catch (IOException e) {
e.printStackTrace();
}
if (isIntent) {
InputStream inputStream = null;
OutputStream realOutputStream = null;
try {
inputStream = new FileInputStream(fileName);
realOutputStream = this.getContentResolver().openOutputStream(fileUri);
// Transfer bytes from in to out
byte[] buffer = new byte[1024];
int len;
while ((len = inputStream.read(buffer)) > 0) {
realOutputStream.write(buffer, 0, len);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
return;
} catch (IOException e) {
e.printStackTrace();
return;
} finally {
try {
inputStream.close();
realOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
animateDocument(fileName, scannedDocument);
Log.d(TAG, "wrote: " + fileName);
if (isIntent) {
new File(fileName).delete();
setResult(RESULT_OK, intent);
finish();
} else {
addImageToGallery(fileName, this);
}
refreshCamera();
}

Google has a page on Mitigating Intent Redirection vulnerabilities that you should read carefully.
The short version is that the vulnerability could potentially1 be exploited by a malicious app to allow it to access private app components or files.
The document explains three possible ways to mitigate this vulnerability. Unfortunately, there is not enough context to be sure which of the three is most appropriate for your app. However, the first one is straightforward:
"If the affected app component does not need to receive Intents from other apps then you can make that app component private by setting `android:exported="false" in your Manifest."
I never updated this part of the code and it never showed any problem before.
That could mean that this is a relatively new kind of Android vulnerability, or that Google's methodology for detecting it has become more rigorous since last time you published your app.
Do I need to update the way of saving a file?
Possibly yes. Or possibly one of the mitigations will be sufficient.
I hope to find a solution here.
There are some possible solutions in the Google document I linked to.
1 - It is moot if it is actually possible to exploit the vulnerability in your app. The point is that Google Play Store's scanning / analysis / testing methodology has found what they believe to be a problem. Their goal is to protect Play Store users.

Reading Large file A, Search Records matching records from file B and write file C in java

I have two files assume its already sorted.
This is just example data, in real ill have around 30-40 Millions of records each file Size 7-10 GB file as row length is big, and fixed.
It's a simple text file, once searched record is found. ill do some update and write to file.
File A may contain 0 or more records of matching ID from File B
Motive is to complete this processing in least amount of time possible.
I am able to do but its time taking process...
Suggestions are welcome.
File A
1000000001,A
1000000002,B
1000000002,C
1000000002,D
1000000002,D
1000000003,E
1000000004,E
1000000004,E
1000000004,E
1000000004,E
1000000005,E
1000000006,A
1000000007,A
1000000008,B
1000000009,B
1000000010,C
1000000011,C
1000000012,C
File B
1000000002
1000000004
1000000006
1000000008
1000000010
1000000012
1000000014
1000000016
1000000018\
// Not working as of now. due to logic is wrong.
private static void readAndWriteFile() {
System.out.println("Read Write File Started.");
long time = System.currentTimeMillis();
try(
BufferedReader in = new BufferedReader(new FileReader(Commons.ROOT_PATH+"input.txt"));
BufferedReader search = new BufferedReader(new FileReader(Commons.ROOT_PATH+"search.txt"));
FileWriter myWriter = new FileWriter(Commons.ROOT_PATH+"output.txt");
) {
String inLine = in.readLine();
String searchLine = search.readLine();
boolean isLoopEnd = true;
while(isLoopEnd) {
if(searchLine == null || inLine == null) {
isLoopEnd = false;
break;
}
if(searchLine.substring(0, 10).equalsIgnoreCase(inLine.substring(0,10))) {
System.out.println("Record Found - " + inLine.substring(0, 10) + " | " + searchLine.substring(0, 10) );
myWriter.write(inLine + System.lineSeparator());
inLine = in.readLine();
}else {
inLine = in.readLine();
}
}
in.close();
myWriter.close();
search.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("Read and Write to File done in - " + (System.currentTimeMillis() - time));
}

My suggestion would be to use a database. As said in this answer. Using txt files has a big disadvantage over DBs. Mostly because of the lack of indexes and the other points mentioned in the answer.
So what I would do, is create a Database (there are lots of good ones out there such as MySQL, PostgreSQL, etc). Create the tables that are needed, and read the file afterward. Insert each line of the file into the DB and use the db to search and update them.
Maybe this would not be an answer to your concrete question on
Motive is to complete this processing in the least amount of time possible.
But this would be a worthy suggestion. Good luck.

With this approach I am able to process 50M Records in 150 Second on i-3, 4GB Ram and SSD Hardrive.
private static void readAndWriteFile() {
System.out.println("Read Write File Started.");
long time = System.currentTimeMillis();
try(
BufferedReader in = new BufferedReader(new FileReader(Commons.ROOT_PATH+"input.txt"));
BufferedReader search = new BufferedReader(new FileReader(Commons.ROOT_PATH+"search.txt"));
FileWriter myWriter = new FileWriter(Commons.ROOT_PATH+"output.txt");
) {
String inLine = in.readLine();
String searchLine = search.readLine();
boolean isLoopEnd = true;
while(isLoopEnd) {
if(searchLine == null || inLine == null) {
isLoopEnd = false;
break;
}
// Since file is already sorted, i was looking for the //ans i found here..
long seachInt = Long.parseLong(searchLineSubString);
long inInt = Long.parseLong(inputLineSubString);
if(searchLine.substring(0, 10).equalsIgnoreCase(inLine.substring(0,10))) {
System.out.println("Record Found - " + inLine.substring(0, 10) + " | " + searchLine.substring(0, 10) );
myWriter.write(inLine + System.lineSeparator());
}
// Which pointer to move..
if(seachInt < inInt) {
searchLine = search.readLine();
}else {
inLine = in.readLine();
}
}
in.close();
myWriter.close();
search.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("Read and Write to File done in - " + (System.currentTimeMillis() - time));
}

How to find directory for File Output Stream in Android app?

I have an app which gets data from an Arduino via bluetooth. The data are written into various ArrayLists and saved in files afterwards. Here is the code:
public boolean SaveValues(ArrayList<String> arrayList1, ArrayList<String> arrayList2, String valueType, String timeStart, String timeStop) {
String filename = "File_" + valueType + "_" + timeStart + " bis " + timeStop;
FileOutputStream outputStream = null;
if(arrayList1.size() == 0)
return false;
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
for (int i = 0; i < arrayList1.size(); i++) {
outputStream.write(arrayList1.get(i).getBytes());
outputStream.write("\n".getBytes());
outputStream.write(arrayList2.get(i).getBytes());
outputStream.write("\n".getBytes());
}
outputStream.close();
return true;
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
I also save the valuetype, timeStart and timeStop into a database to be able to find the files. My problem is, that somehow the table where I save these values got deleted, so I am not able to find the files in the app. I would like to find the files maybe on the phone or something. Actually, I just need the filenames to be able to open them in the app, because they contain data I need. So, where can I find these files?
I have tried searching in the phones files. The files, and all the other apps data, should be saved in Android/data/package-name but I can't find the package name in Android/data. I also tried to search for "File_" in the files, because that's what every one of my files start with. But no file gets found.

Downloading an image in java

I have to download an image from the nasa website. Problem is, that my code sometimes works, sucessfully downloading an image, while sometimes saves only 186B (don't know why exactly 186).
Problems is for sure connected with the way nasa sahres those photos. For instance, an image from that link https://mars.jpl.nasa.gov/msl-raw-images/msss/00001/mcam/0001ML0000001000I1_DXXX.jpg is saved sucessfully, while from that link https://mars.nasa.gov/mer/gallery/all/2/f/001/2F126468064EDN0000P1001L0M1-BR.JPG fails.
Here is my code
public static void saveImage(String imageUrl, String destinationFile){
URL url;
try {
url = new URL(imageUrl);
System.out.println(url);
InputStream is = url.openStream();
OutputStream os = new FileOutputStream(destinationFile);
byte[] b = new byte[2048];
int length;
while ((length = is.read(b)) != -1) {
os.write(b, 0, length);
}
is.close();
os.close();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Does someone have an idea, why is doesn't work?
public boolean downloadPhotosSol(int i) throws JSONException, IOException {
String url0 = "https://api.nasa.gov/mars-photos/api/v1/rovers/spirit/photos?sol=" + this.chosenMarsDate + "&camera=" + this.chosenCamera + "&page=" + i + "&api_key=###";
JSONObject json = JsonReader.readJsonFromUrl(url0);
if(json.getJSONArray("photos").length() == 0) return true;
String workspace = new File(".").getCanonicalPath();
String pathToFolder = workspace+File.separator+this.getManifest().getName() + this.chosenMarsDate + this.chosenCamera +"Strona"+i;
new File(pathToFolder).mkdirs();
for(int j = 0;j<json.getJSONArray("photos").length();j++) {
String url = ((JSONObject) json.getJSONArray("photos").get(j)).getString("img_src");
SaveImage.saveImage(url, pathToFolder+File.separator+"img"+j+".jpg");
}
return false;
}

When you get a 186 byte file, open it with a text editor and see what is inside. It could contain an HTTP error message in HTML format. If instead you see the first 186 bytes of your image file, then something is not working right with your program.
EDIT: From your comments it looks like you are getting an HTTP 301 response, which is a redirect to another location. A web browser handles this automatically without you noticing. However, your Java program is not following the redirect to the new location. You need to use an HTTP Java library that handles redirects.

Best and short way of doing it:
try(InputStream in = new URL("http://example.com/image.jpg").openStream()){
Files.copy(in, Paths.get("C:/File/To/Save/To/image.jpg"));
}

Get percentage of extraction with XZ Java for android

I am using the XZ Java library to extract a .xz file on Android of size around 16MB. I am running the extraction/decompression code as an AsyncTask and so, I would like to see the percentage of extraction via the onProgressUpdate(Integer ... values) method.
My decompression code looks something like this.
byte[] buf = new byte[8192];
String name = null;
try {
name = "my_archive.xz";
InputStream in = getResources().openRawResource(R.raw.my_archive);//new FileInputStream(name); //
FileOutputStream out = openFileOutput("my_archive.sqlite", Context.MODE_PRIVATE);
label = (TextView)findViewById(R.id.textLabel);
try {
in = new XZInputStream(in);
label.setText("Writing db file.");
int size;
while ((size = in.read(buf)) != -1) {
out.write(buf,0,size);
progress++;
publishProgress(progress);
}
}
catch (Exception e)
{
System.err.println("Input Stream error: "+e.getMessage());
}
finally {
// Close FileInputStream (directly or indirectly
// via LZMAInputStream, it doesn't matter).
in.close();
}
} catch (FileNotFoundException e) {
System.err.println("LZMADecDemo: Cannot open " + name + ": "
+ e.getMessage());
System.exit(1);
} catch (EOFException e) {
System.err.println("LZMADecDemo: Unexpected end of input on "
+ name);
System.exit(1);
} catch (IOException e) {
System.err.println("LZMADecDemo: Error decompressing from "
+ name + ": " + e.getMessage());
System.exit(1);
}
The progress variable should actually hold the percentage value. If anyone has worked with this library, and if you figured out an easy way to calculate the percentage of progress please help me out here.
Thanks in advance for the help.

I tried to get the size of the archive file using the available() method on the inputstream like below.
InputStream in = getResources().openRawResource(R.raw.my_archive);
int fileSize = in.available();
And during extraction process, I calculated progress like below:
int size;
int counter=0;
while ((size = in.read(buf)) != -1) {
out.write(buf,0,size);
counter++;
progress = (int) (counter*100*1024/(double)fileSize);
publishProgress(progress);
}
However, this doesn't result in the right progress for some reason. The progress goes upto 108% before its finished. I know I'm doing something wrong here, so please improve this answer with the right calculation.
Thanks