Copy shared content local

app/src/main/java/eu/faircode/email/ActivityMain.java

@@ -26,11 +26,17 @@ import android.content.res.Configuration;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
+import android.text.TextUtils;
 
+import androidx.core.content.FileProvider;
+import androidx.documentfile.provider.DocumentFile;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
 import androidx.preference.PreferenceManager;
 
+import java.io.File;
+import java.io.FileOutputStream;
+import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
 
@@ -97,6 +103,7 @@ public class ActivityMain extends ActivityBase implements FragmentManager.OnBack
                                 (Intent.ACTION_SENDTO.equals(action) && mailto) ||
                                 Intent.ACTION_SEND.equals(action) ||
                                 Intent.ACTION_SEND_MULTIPLE.equals(action)) {
+                            processStreams(intent);
                             intent.setClass(ActivityMain.this, ActivityCompose.class);
                             startActivity(intent);
                             finish();
@@ -139,6 +146,60 @@ public class ActivityMain extends ActivityBase implements FragmentManager.OnBack
                 protected void onException(Bundle args, Throwable ex) {
                     Log.unexpectedError(getSupportFragmentManager(), ex);
                 }
+
+                // Copy content local to prevent security exceptions
+                private void processStreams(Intent intent) {
+                    intent.setClipData(null);
+
+                    if (intent.hasExtra(Intent.EXTRA_STREAM)) {
+                        if (Intent.ACTION_SEND_MULTIPLE.equals(intent.getAction())) {
+                            ArrayList<Uri> uris = intent.getParcelableArrayListExtra(Intent.EXTRA_STREAM);
+                            if (uris == null)
+                                intent.removeExtra(Intent.EXTRA_STREAM);
+                            else {
+                                ArrayList<Uri> processed = new ArrayList<>();
+                                for (Uri uri : uris)
+                                    processed.add(processUri(uri));
+                                intent.putParcelableArrayListExtra(Intent.EXTRA_STREAM, processed);
+                            }
+                        } else {
+                            Uri uri = intent.getParcelableExtra(Intent.EXTRA_STREAM);
+                            if (uri == null)
+                                intent.removeExtra(Intent.EXTRA_STREAM);
+                            else
+                                intent.putExtra(Intent.EXTRA_STREAM, processUri(uri));
+                        }
+                    }
+                }
+
+                private Uri processUri(Uri uri) {
+                    try {
+                        String fname = null;
+                        try {
+                            DocumentFile dfile = DocumentFile.fromSingleUri(ActivityMain.this, uri);
+                            if (dfile != null)
+                                fname = dfile.getName();
+                        } catch (SecurityException ex) {
+                            Log.e(ex);
+                        }
+
+                        if (TextUtils.isEmpty(fname))
+                            fname = uri.getLastPathSegment();
+
+                        File dir = new File(getCacheDir(), "shared");
+                        if (!dir.exists())
+                            dir.mkdir();
+                        File file = new File(dir, fname);
+
+                        Log.i("Copying shared file to " + file);
+                        Helper.copy(getContentResolver().openInputStream(uri), new FileOutputStream(file));
+
+                        return FileProvider.getUriForFile(ActivityMain.this, BuildConfig.APPLICATION_ID, file);
+                    } catch (Throwable ex) {
+                        Log.w(ex);
+                        return uri;
+                    }
+                }
             };
 
             if (Helper.shouldAuthenticate(this))

app/src/main/res/xml/fileprovider_paths.xml

@@ -12,4 +12,7 @@
     <cache-path
         name="calendar"
         path="calendar" />
+    <cache-path
+        name="shared"
+        path="shared" />
 </paths>