Add a check for wrong file selection during private key import

Also added some tests for PK import.

app/src/androidTest/java/com/gaurav/avnc/Helpers.kt

@@ -8,23 +8,31 @@
 
 package com.gaurav.avnc
 
+import android.app.Activity
+import android.app.Instrumentation
 import android.content.ClipData
 import android.content.ClipboardManager
 import android.content.Context
+import android.content.Intent
 import android.os.SystemClock
 import android.view.View
 import android.widget.ProgressBar
+import androidx.core.net.toUri
 import androidx.preference.PreferenceManager
 import androidx.test.espresso.NoMatchingViewException
 import androidx.test.espresso.ViewAssertion
 import androidx.test.espresso.ViewInteraction
 import androidx.test.espresso.action.ViewActions.*
 import androidx.test.espresso.assertion.ViewAssertions.matches
+import androidx.test.espresso.intent.Intents
+import androidx.test.espresso.intent.matcher.IntentMatchers
 import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
 import androidx.test.platform.app.InstrumentationRegistry
 import junit.framework.AssertionFailedError
 import org.hamcrest.core.IsNot.not
 import org.junit.Assert
+import java.io.BufferedWriter
+import java.io.File
 
 /**
  * Global accessors
@@ -93,4 +101,21 @@ class ProgressAssertion(private val test: (Int) -> Boolean) : ViewAssertion {
         if (view !is ProgressBar) throw AssertionFailedError("View is not a ProgressBar")
         Assert.assertTrue("Progress test failed for '${view.progress}'", test(view.progress))
     }
-}
+}
+
+/**
+ * Helper for testing file selection by user.
+ *
+ * It creates a temporary file, populated by invoking [fileWriter]
+ * Then Intent response is hooked up to return that file.
+ *
+ * Note: [Intents.init] must have been called before using this function
+ */
+fun setupFileOpenIntent(fileWriter: BufferedWriter.() -> Unit) {
+    val file = File.createTempFile("avnc", "test")
+    file.bufferedWriter().use { it.fileWriter() }
+    Intents.intending(IntentMatchers.hasAction(Intent.ACTION_OPEN_DOCUMENT))
+            .respondWith(Instrumentation.ActivityResult(Activity.RESULT_OK, Intent().setData(file.toUri())))
+}
+
+fun setupFileOpenIntent(fileContent: String) = setupFileOpenIntent { write(fileContent) }

app/src/androidTest/java/com/gaurav/avnc/ui/home/ProfileEditorTest.kt

@@ -8,21 +8,26 @@
 
 package com.gaurav.avnc.ui.home
 
+import androidx.core.content.edit
 import androidx.test.espresso.Espresso.closeSoftKeyboard
 import androidx.test.espresso.Espresso.onView
+import androidx.test.espresso.action.ScrollToAction
+import androidx.test.espresso.intent.Intents
 import androidx.test.espresso.matcher.RootMatchers.isDialog
 import androidx.test.espresso.matcher.ViewMatchers.*
 import androidx.test.ext.junit.rules.ActivityScenarioRule
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import com.gaurav.avnc.*
 import com.gaurav.avnc.model.ServerProfile
 import org.hamcrest.core.AllOf.allOf
+import org.junit.After
+import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 
 @RunWith(AndroidJUnit4::class)
-class ProfileEditorTest {
+class BasicEditorTest {
 
     private val testProfile = ServerProfile(name = "foo", host = "bar")
 
@@ -68,6 +73,70 @@ class ProfileEditorTest {
                 hasDescendant(withText(testProfile.host)))
         ).checkWillBeDisplayed()
     }
+}
 
-    //TODO add more tests
+@RunWith(AndroidJUnit4::class)
+class PrivateKeyTest {
+
+    private val SAMPLE_KEY = """
+        -----BEGIN EC PRIVATE KEY-----
+        MHcCAQEEIOlzJCBaTq2RpkLatMn+PMwsQ/ncijqK5M6y5kPns+BAoAoGCCqGSM49
+        AwEHoUQDQgAE5vfo9Is5+pnk+6dC3NlXA9rKNy0X6PdifyeI2OKKTGVA4cdhEOBh
+        MXTgJKarp26FiFnsFuWEGOO61Q/Plmv8Wg==
+        -----END EC PRIVATE KEY-----
+    """.trimIndent()
+
+    private val SAMPLE_ENCRYPTED_KEY = """
+        -----BEGIN EC PRIVATE KEY-----
+        Proc-Type: 4,ENCRYPTED
+        DEK-Info: AES-128-CBC,D18B845F2B9D4B9FEB3472809F270AD2
+
+        fNNjQEFap5uf3+gaQNI+A2ait7WZDjxPO6sT6MfOTQ34/HRxm7El4FWhhYMfIiGl
+        5j/A30Je2OMbOEqTpiKZKYxKxWIZ27te8HpxsQkC9xvU9rxPPsd0Vt/7na5rbx1S
+        Iqfy2ows7NJY3f3s/GlMY2ZmaAwk6TJ3DAJ+YK0KMrc=
+        -----END EC PRIVATE KEY-----
+    """.trimIndent()
+
+    @Rule
+    @JvmField
+    val activityRule = ActivityScenarioRule(HomeActivity::class.java)
+
+    @Before
+    fun before() {
+        Intents.init()
+        targetPrefs.edit { putBoolean("prefer_advanced_editor", true) }
+        onView(withContentDescription(R.string.desc_add_new_server_btn)).doClick()
+        onView(withId(R.id.use_ssh_tunnel)).perform(ScrollToAction())
+        onView(withId(R.id.use_ssh_tunnel)).doClick()
+        onView(withId(R.id.key_import_btn)).perform(ScrollToAction())
+    }
+
+    @After
+    fun after() {
+        targetPrefs.edit { putBoolean("prefer_advanced_editor", false) }
+        Intents.release()
+    }
+
+    @Test
+    fun importValidPK() {
+        setupFileOpenIntent(SAMPLE_KEY)
+        onView(withId(R.id.key_import_btn)).doClick()
+        onView(withText(R.string.msg_imported)).checkWillBeDisplayed()
+        onView(withId(R.id.ssh_key_password)).checkIsNotDisplayed()
+    }
+
+    @Test
+    fun importEncryptedPK() {
+        setupFileOpenIntent(SAMPLE_ENCRYPTED_KEY)
+        onView(withId(R.id.key_import_btn)).doClick()
+        onView(withText(R.string.msg_imported)).checkWillBeDisplayed()
+        onView(withId(R.id.ssh_key_password)).checkWillBeDisplayed()
+    }
+
+    @Test
+    fun importInvalidFile() {
+        setupFileOpenIntent("This is not a Private Key, right?")
+        onView(withId(R.id.key_import_btn)).doClick()
+        onView(withText(R.string.msg_invalid_key_file)).checkWillBeDisplayed()
+    }
 }

app/src/main/java/com/gaurav/avnc/ui/home/ProfileEditorFragment.kt

@@ -11,6 +11,7 @@ package com.gaurav.avnc.ui.home
 import android.app.Dialog
 import android.net.Uri
 import android.os.Bundle
+import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -304,20 +305,28 @@ class ProfileEditorFragment : DialogFragment() {
             return
 
         lifecycleScope.launch(Dispatchers.IO) {
-
-            val text = requireContext().contentResolver.openInputStream(uri).use { it?.reader()?.readText() ?: "" }
-            val pem = runCatching { PEMDecoder.parsePEM(text.toCharArray()) }
-            val encrypted = runCatching { PEMDecoder.isPEMEncrypted(pem.getOrNull()) }.getOrNull() ?: false
+            var key = ""
+            var encrypted = false
+            val result = runCatching {
+                requireContext().contentResolver.openAssetFileDescriptor(uri, "r")!!.use {
+                    // Valid key files are only few KBs. So if selected file is too big,
+                    // user has accidentally selected something else.
+                    check(it.length < 200 * 1024) { "File is too big [${it.length}]" }
+                    key = it.createInputStream().use { s -> s.reader().use { r -> r.readText() } }
+                }
+                encrypted = PEMDecoder.isPEMEncrypted(PEMDecoder.parsePEM(key.toCharArray()))
+            }
 
             lifecycleScope.launchWhenCreated {
-                if (pem.isSuccess) {
-                    profile.sshPrivateKey = text
+                result.onSuccess {
+                    profile.sshPrivateKey = key
                     binding.keyImportBtn.setText(R.string.title_change)
                     binding.keyImportBtn.error = null
                     binding.isPrivateKeyEncrypted = encrypted
                     Snackbar.make(requireView(), R.string.msg_imported, Snackbar.LENGTH_SHORT).show()
-                } else {
+                }.onFailure {
                     Snackbar.make(requireView(), R.string.msg_invalid_key_file, Snackbar.LENGTH_LONG).show()
+                    Log.e("ProfileEditor", "Error importing Private Key", it)
                 }
             }
         }