Checking volume paths before opening

app/src/main/java/sushi/hardcore/droidfs/ChangePasswordActivity.kt

@@ -110,7 +110,14 @@ class ChangePasswordActivity : BaseActivity() {
         if (rootCipherDir.isEmpty()) {
             Toast.makeText(this, R.string.enter_volume_path, Toast.LENGTH_SHORT).show()
         } else {
-            if (!File(rootCipherDir).canWrite()){
+            val rootCipherDirFile = File(rootCipherDir)
+            if (!GocryptfsVolume.isGocryptfsVolume(rootCipherDirFile)){
+                ColoredAlertDialogBuilder(this)
+                    .setTitle(R.string.error)
+                    .setMessage(R.string.error_not_a_volume)
+                    .setPositiveButton(R.string.ok, null)
+                    .show()
+            } else if (!rootCipherDirFile.canWrite()){
                 ColoredAlertDialogBuilder(this)
                     .setTitle(R.string.warning)
                     .setMessage(R.string.change_pwd_cant_write_error_msg)

app/src/main/java/sushi/hardcore/droidfs/ConstValues.kt

@@ -6,6 +6,7 @@ import java.io.File
 class ConstValues {
     companion object {
         const val creator = "DroidFS"
+        const val gocryptfsConfFilename = "gocryptfs.conf"
         const val saved_volumes_key = "saved_volumes"
         const val sort_order_key = "sort_order"
         val fakeUri: Uri = Uri.parse("fakeuri://droidfs")

app/src/main/java/sushi/hardcore/droidfs/OpenActivity.kt

@@ -115,7 +115,14 @@ class OpenActivity : BaseActivity() {
         if (rootCipherDir.isEmpty()) {
             Toast.makeText(this, R.string.enter_volume_path, Toast.LENGTH_SHORT).show()
         } else {
-            if (!File(rootCipherDir).canWrite()){
+            val rootCipherDirFile = File(rootCipherDir)
+            if (!GocryptfsVolume.isGocryptfsVolume(rootCipherDirFile)){
+                ColoredAlertDialogBuilder(this)
+                    .setTitle(R.string.error)
+                    .setMessage(R.string.error_not_a_volume)
+                    .setPositiveButton(R.string.ok, null)
+                    .show()
+            } else if (!rootCipherDirFile.canWrite()) {
                 ColoredAlertDialogBuilder(this)
                     .setTitle(R.string.warning)
                     .setMessage(R.string.open_cant_write_warning)

app/src/main/java/sushi/hardcore/droidfs/util/GocryptfsVolume.kt

@@ -2,7 +2,9 @@ package sushi.hardcore.droidfs.util
 
 import android.content.Context
 import android.net.Uri
+import sushi.hardcore.droidfs.ConstValues
 import sushi.hardcore.droidfs.explorers.ExplorerElement
+import java.io.File
 import java.io.FileOutputStream
 import java.io.InputStream
 import java.io.OutputStream
@@ -32,6 +34,13 @@ class GocryptfsVolume(var sessionID: Int) {
         external fun init(root_cipher_dir: String, password: CharArray?, givenHash: ByteArray?, returnedHash: ByteArray?): Int
         external fun changePassword(root_cipher_dir: String, old_password: CharArray?, givenHash: ByteArray?, new_password: CharArray, returnedHash: ByteArray?): Boolean
 
+        fun isGocryptfsVolume(path: File): Boolean {
+            if (path.isDirectory){
+                return File(path, ConstValues.gocryptfsConfFilename).isFile
+            }
+            return false
+        }
+
         init {
             System.loadLibrary("gocryptfs_jni")
         }

app/src/main/res/values/strings.xml

@@ -33,7 +33,7 @@
     <string name="success_volume_create_msg">The volume has been successfully created.</string>
     <string name="create_volume_failed">The volume creation has failed.</string>
     <string name="open_volume_failed">Open failed</string>
-    <string name="open_volume_failed_msg">Failed to open the volume. Check the selected volume path and the entered password.</string>
+    <string name="open_volume_failed_msg">Failed to open the volume. Please check your password.</string>
     <string name="share_chooser">Share File</string>
     <string name="storage_unavailable">Storage unavailable</string>
     <string name="storage_unavailable_msg">DroidFS can\'t work without storage access.</string>
@@ -68,7 +68,7 @@
     <string name="new_password_confirmation">New Password (confirmation):</string>
     <string name="success_change_password">Password successfully changed !</string>
     <string name="success_change_password_msg">The volume\'s password has been successfully changed.</string>
-    <string name="change_password_failed">Failed to change the volume\'s password. Check the selected volume path and the entered old password.</string>
+    <string name="change_password_failed">Operation failed. Please check your old password.</string>
     <string name="share_menu_label">Encrypt with DroidFS</string>
     <string name="share_intent_parsing_failed">Failed to handle the share request.</string>
     <string name="listdir_null_error_msg">Unable to access this directory</string>
@@ -177,4 +177,5 @@
     <string name="image_saved_successfully">Image changes successfully saved.</string>
     <string name="bitmap_compress_failed">Failed to compress the bitmap.</string>
     <string name="file_write_failed">Failed to write the file.</string>
+    <string name="error_not_a_volume">Gocryptfs volume not recognized. Please check the selected path.</string>
 </resources>