Decrypt protect content inline

This commit is contained in:
M66B 2022-10-22 19:36:11 +02:00
parent 52f4f2acf9
commit 4a62e23cc4
5 changed files with 322 additions and 5 deletions

View File

@ -5854,6 +5854,16 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
Log.i("Opening uri=" + uri + " title=" + title);
uri = Uri.parse(uri.toString().replaceAll("\\s+", ""));
if (StyleHelper.isProtectedContent(uri)) {
Bundle args = new Bundle();
args.putParcelable("uri", uri);
FragmentDialogBase dialog = new StyleHelper.FragmentDialogDecrypt();
dialog.setArguments(args);
dialog.show(parentFragment.getParentFragmentManager(), "decrypt");
return true;
}
try {
String url = uri.getQueryParameter("url");
if (!TextUtils.isEmpty(url)) {

View File

@ -19,6 +19,7 @@ package eu.faircode.email;
Copyright 2018-2022 by Marcel Bokhorst (M66B)
*/
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
@ -28,6 +29,7 @@ import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Typeface;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.text.Editable;
@ -39,6 +41,7 @@ import android.text.Spanned;
import android.text.TextPaint;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.text.method.ArrowKeyMovementMethod;
import android.text.style.AlignmentSpan;
import android.text.style.BackgroundColorSpan;
import android.text.style.BulletSpan;
@ -54,17 +57,22 @@ import android.text.style.URLSpan;
import android.text.style.UnderlineSpan;
import android.util.Base64;
import android.util.Pair;
import android.view.GestureDetector;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.SubMenu;
import android.view.View;
import android.view.WindowManager;
import android.view.inputmethod.EditorInfo;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.widget.PopupMenu;
import androidx.core.content.ContextCompat;
@ -84,6 +92,7 @@ import java.io.ByteArrayOutputStream;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.SecureRandom;
import java.security.spec.KeySpec;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
@ -94,10 +103,16 @@ import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
public class StyleHelper {
private static final int MAX_PROTECTED_TEXT = 1500;
private static final int DECRYPT_ITERATIONS = 120000;
private static final int DECRYPT_KEYLEN = 256;
private static final String DECRYPT_DERIVATION = "PBKDF2WithHmacSHA512";
private static final int DECRYPT_TAGLEN = 128;
private static final String DECRYPT_TRANSFORMATION = "AES/GCM/NoPadding";
private static final String DECRYPT_URL = "https://fairemail.net/decrypt/";
private static final List<Class> CLEAR_STYLES = Collections.unmodifiableList(Arrays.asList(
@ -641,15 +656,15 @@ public class StyleHelper {
random.nextBytes(iv);
// Iterations = 120,000; Keylength = 256 bits = 32 bytes
PBEKeySpec spec = new PBEKeySpec(password.toCharArray(), salt, 120000, 256);
PBEKeySpec spec = new PBEKeySpec(password.toCharArray(), salt, DECRYPT_ITERATIONS, DECRYPT_KEYLEN);
SecretKeyFactory skf = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA512");
SecretKeyFactory skf = SecretKeyFactory.getInstance(DECRYPT_DERIVATION);
SecretKey key = skf.generateSecret(spec);
// Authentication tag length = 128 bits = 16 bytes
GCMParameterSpec parameterSpec = new GCMParameterSpec(128, iv);
GCMParameterSpec parameterSpec = new GCMParameterSpec(DECRYPT_TAGLEN, iv);
final Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
final Cipher cipher = Cipher.getInstance(DECRYPT_TRANSFORMATION);
cipher.init(Cipher.ENCRYPT_MODE, key, parameterSpec);
byte[] cipherText = cipher.doFinal(html.getBytes(StandardCharsets.UTF_8));
@ -1463,5 +1478,203 @@ public class StyleHelper {
}
}
public static boolean isProtectedContent(Uri uri) {
return uri.toString().startsWith(DECRYPT_URL);
}
public static final class FragmentDialogDecrypt extends FragmentDialogBase {
@NonNull
@Override
public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) {
Bundle args = getArguments();
final Context context = getContext();
final View view = LayoutInflater.from(context).inflate(R.layout.dialog_decrypt, null);
final TextInputLayout tilPassword = view.findViewById(R.id.tilPassword);
final Button btnDecrypt = view.findViewById(R.id.btnDecrypt);
final TextView tvContent = view.findViewById(R.id.tvContent);
final TextView tvError = view.findViewById(R.id.tvError);
final TextView tvErrorDetail = view.findViewById(R.id.tvErrorDetail);
tilPassword.setVisibility(View.VISIBLE);
btnDecrypt.setVisibility(View.VISIBLE);
tvContent.setVisibility(View.GONE);
tvError.setVisibility(View.GONE);
tvErrorDetail.setVisibility(View.GONE);
String password = args.getString("password");
tilPassword.getEditText().setText(password);
btnDecrypt.setEnabled(!TextUtils.isEmpty(password));
tilPassword.getEditText().addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// Do nothing
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// Do nothing
}
@Override
public void afterTextChanged(Editable s) {
String password = s.toString();
btnDecrypt.setEnabled(!TextUtils.isEmpty(password));
args.putString("password", password);
}
});
btnDecrypt.setEnabled(false);
tvContent.setMovementMethod(new ArrowKeyMovementMethod() {
private GestureDetector gestureDetector = new GestureDetector(context,
new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onSingleTapUp(MotionEvent event) {
return onClick(event);
}
private boolean onClick(MotionEvent event) {
Spannable buffer = (Spannable) tvContent.getText();
int off = Helper.getOffset(tvContent, buffer, event);
URLSpan[] link = buffer.getSpans(off, off, URLSpan.class);
if (link.length > 0) {
String url = link[0].getURL();
Uri uri = Uri.parse(url);
int start = buffer.getSpanStart(link[0]);
int end = buffer.getSpanEnd(link[0]);
String title = (start < 0 || end < 0 || end <= start
? null : buffer.subSequence(start, end).toString());
if (url.equals(title))
title = null;
Bundle args = new Bundle();
args.putParcelable("uri", uri);
args.putString("title", title);
FragmentDialogOpenLink fragment = new FragmentDialogOpenLink();
fragment.setArguments(args);
fragment.show(getParentFragmentManager(), "open:link");
return true;
}
return false;
}
});
@Override
public boolean onTouchEvent(TextView widget, Spannable buffer, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
});
btnDecrypt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
new SimpleTask<Spanned>() {
@Override
protected void onPreExecute(Bundle args) {
tilPassword.setEnabled(false);
btnDecrypt.setEnabled(false);
tvError.setVisibility(View.GONE);
tvErrorDetail.setVisibility(View.GONE);
}
@Override
protected void onPostExecute(Bundle args) {
tilPassword.setEnabled(true);
btnDecrypt.setEnabled(true);
}
@Override
protected Spanned onExecute(Context context, Bundle args) throws Throwable {
Uri uri = args.getParcelable("uri");
String password = args.getString("password");
byte[] msg = Base64.decode(uri.getFragment(), Base64.URL_SAFE | Base64.NO_WRAP);
int version = msg[0];
byte[] salt = new byte[16]; // 128 bits
System.arraycopy(msg, 1, salt, 0, salt.length);
byte[] iv = new byte[12]; // 96 bites
System.arraycopy(msg, 1 + salt.length, iv, 0, iv.length);
byte[] encrypted = new byte[msg.length - 1 - salt.length - iv.length];
System.arraycopy(msg, 1 + salt.length + iv.length, encrypted, 0, encrypted.length);
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DECRYPT_DERIVATION);
KeySpec keySpec = new PBEKeySpec(password.toCharArray(), salt, DECRYPT_ITERATIONS, DECRYPT_KEYLEN);
SecretKey secret = keyFactory.generateSecret(keySpec);
Cipher cipher = Cipher.getInstance(DECRYPT_TRANSFORMATION);
IvParameterSpec ivSpec = new IvParameterSpec(iv);
cipher.init(Cipher.DECRYPT_MODE, secret, ivSpec);
byte[] decrypted = cipher.doFinal(encrypted);
String html = new String(decrypted, StandardCharsets.UTF_8);
return HtmlHelper.fromHtml(html, new HtmlHelper.ImageGetterEx() {
@Override
public Drawable getDrawable(Element element) {
return ImageHelper.decodeImage(context,
-1, element, true, 0, 1.0f, tvContent);
}
}, null, context);
}
@Override
protected void onExecuted(Bundle args, Spanned content) {
tilPassword.setVisibility(View.GONE);
btnDecrypt.setVisibility(View.GONE);
tvContent.setText(content);
tvContent.setVisibility(View.VISIBLE);
}
@Override
protected void onException(Bundle args, Throwable ex) {
tvError.setText(ex.getMessage());
tvErrorDetail.setText(ex.toString());
tvError.setVisibility(View.VISIBLE);
tvErrorDetail.setVisibility(View.VISIBLE);
}
}.execute(FragmentDialogDecrypt.this, args, "decypt");
}
});
tilPassword.getEditText().setOnEditorActionListener(new TextView.OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_DONE) {
btnDecrypt.performClick();
return true;
} else
return false;
}
});
if (!TextUtils.isEmpty(password))
btnDecrypt.post(new Runnable() {
@Override
public void run() {
btnDecrypt.performClick();
}
});
Dialog dialog = new AlertDialog.Builder(context)
.setView(view)
.setNegativeButton(android.R.string.cancel, null)
.create();
dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
return dialog;
}
}
//TextUtils.dumpSpans(text, new LogPrinter(android.util.Log.INFO, "FairEmail"), "afterTextChanged ");
}

View File

@ -0,0 +1,92 @@
<?xml version="1.0" encoding="utf-8"?>
<eu.faircode.email.ScrollViewEx xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="24dp"
android:scrollbarStyle="outsideOverlay">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="@+id/tvCaption"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:drawableStart="@drawable/twotone_lock_24"
android:drawablePadding="6dp"
android:text="@string/title_style_protected"
android:textAppearance="@style/TextAppearance.AppCompat.Large"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/tilPassword"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="24dp"
app:endIconMode="password_toggle"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/tvCaption">
<com.google.android.material.textfield.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:autofillHints="password"
android:hint="@string/title_setup_password"
android:imeOptions="actionDone"
android:inputType="textPassword"
android:textAppearance="@style/TextAppearance.AppCompat.Medium">
<requestFocus />
</com.google.android.material.textfield.TextInputEditText>
</com.google.android.material.textfield.TextInputLayout>
<Button
android:id="@+id/btnDecrypt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="12dp"
android:drawableEnd="@drawable/twotone_lock_open_24"
android:drawablePadding="6dp"
android:text="@string/title_decrypt"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/tilPassword" />
<TextView
android:id="@+id/tvContent"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="24dp"
android:text="Secret"
android:textAppearance="@style/TextAppearance.AppCompat.Medium"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/btnDecrypt" />
<TextView
android:id="@+id/tvError"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="24dp"
android:text="Error"
android:textAppearance="@style/TextAppearance.AppCompat.Medium"
android:textColor="?attr/colorWarning"
android:textStyle="bold"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/tvContent" />
<TextView
android:id="@+id/tvErrorDetail"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="12dp"
android:fontFamily="monospace"
android:text="Details"
android:textAppearance="@style/TextAppearance.AppCompat.Small"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/tvError" />
</androidx.constraintlayout.widget.ConstraintLayout>
</eu.faircode.email.ScrollViewEx>

View File

@ -1217,7 +1217,8 @@ Het blokkeren van een afzenderdomein maakt gebruik van filterregels, wat een pro
<string name="title_style_subscript">Subscript</string>
<string name="title_style_superscript">Superscript</string>
<string name="title_style_strikethrough">Doorhalen</string>
<string name="title_style_protect">Beveiligd met wachtwoord</string>
<string name="title_style_protect">Beveilig met wachtwoord</string>
<string name="title_style_protected" comment="title_style_protected&#10;Title of dialog to decrypt protect content">Beschermde inhoud</string>
<string name="title_style_protect_size">Te lange tekst</string>
<string name="title_style_clear">Opmaak wissen</string>
<string name="title_style_link">Koppeling invoegen</string>

View File

@ -1450,6 +1450,7 @@
<string name="title_style_strikethrough">Strikethrough</string>
<string name="title_style_code" translatable="false">Code</string>
<string name="title_style_protect">Password protect</string>
<string name="title_style_protected">Protected content</string>
<string name="title_style_protect_size">Text too long</string>
<string name="title_style_clear">Clear formatting</string>
<string name="title_style_link">Insert link</string>