1
0
AES-secured-notepad/app/src/main/java/com/example/bsm_notatnik/MainActivity.java
2023-12-05 23:53:17 +01:00

416 lines
16 KiB
Java

package com.example.bsm_notatnik;
import android.annotation.SuppressLint;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import java.security.GeneralSecurityException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.util.ArrayList;
import java.util.Base64;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.crypto.BadPaddingException;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
public class MainActivity extends AppCompatActivity {
Button buttonLogout, buttonChangePassword, buttonAddNewNote;
private static final String SHARED_NAME_CREDENTIALS = "Credentials";
private static final String SHARED_NAME_NOTES = "Notes";
private static String HASHED_EMAIL = "";
private static String PAS = "";
private List<Note> noteList;
private LinearLayout notesContainer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent intent = getIntent();
String current_username_hashed = intent.getStringExtra("CURRENT_USER_EMAIL_HASH");
HASHED_EMAIL = current_username_hashed;
PAS = intent.getStringExtra("PAS");
notesContainer = findViewById(R.id.notesContainer);
noteList = new ArrayList<>();
try {
loadNotesFromPreferencesToList();
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
displayNotes();
buttonLogout = findViewById(R.id.btn_logout);
buttonChangePassword = findViewById(R.id.btn_change_password);
buttonAddNewNote = findViewById(R.id.btn_add_note);
buttonLogout.setOnClickListener(view -> logOut());
buttonChangePassword.setOnClickListener(view -> showPasswordChangeDialog(current_username_hashed));
buttonAddNewNote.setOnClickListener(view -> showAddNewNoteDialog());
}
private void logOut(){
Intent intent = new Intent(getApplicationContext(), Login.class);
startActivity(intent);
finish();
}
private void showPasswordChangeDialog(String hashedEmail){
LayoutInflater inflater = getLayoutInflater();
View dialogView = inflater.inflate(R.layout.password_change_dialog, null);
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setView(dialogView);
builder.setTitle("Change Password");
builder.setPositiveButton("Change", (dialogInterface, i) -> {
EditText editTextOldPassword = dialogView.findViewById(R.id.editTextOldPassword);
EditText editTextNewPassword = dialogView.findViewById(R.id.editTextNewPassword);
EditText editTextConfirmPassword = dialogView.findViewById(R.id.editTextConfirmPassword);
String oldPassword = editTextOldPassword.getText().toString();
String newPassword = editTextNewPassword.getText().toString();
String confirmPassword = editTextConfirmPassword.getText().toString();
if (TextUtils.isEmpty(oldPassword) || TextUtils.isEmpty(newPassword) || TextUtils.isEmpty(confirmPassword)) {
Toast.makeText(MainActivity.this, "Fill out all 3 fields!", Toast.LENGTH_SHORT).show();
return;
}
if(!validatePassword(newPassword)){
Toast.makeText(MainActivity.this, "New password to weak!", Toast.LENGTH_SHORT).show();
return;
}
if(!validateOldPassword(hashedEmail, oldPassword)){
Toast.makeText(MainActivity.this, "Old password not correct!", Toast.LENGTH_SHORT).show();
return;
}
if (newPassword.equals(confirmPassword)) {
try {
updatePassword(hashedEmail, newPassword);
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
} else {
Toast.makeText(MainActivity.this, "New passwords don't match!", Toast.LENGTH_SHORT).show();
}
});
builder.setNegativeButton("Cancel", (dialogInterface, i) -> dialogInterface.dismiss());
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
private void showAddNewNoteDialog(){
LayoutInflater inflater = getLayoutInflater();
View dialogView = inflater.inflate(R.layout.create_note_dialog, null);
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setView(dialogView);
builder.setTitle("Create new note");
builder.setPositiveButton("Save", (dialogInterface, i) -> {
EditText noteTitleEditText = dialogView.findViewById(R.id.noteTitleEditText);
EditText noteContentEditText = dialogView.findViewById(R.id.noteContentEditText);
String title = noteTitleEditText.getText().toString();
String content = noteContentEditText.getText().toString();
if (!title.isEmpty() && !content.isEmpty()){
Note note = new Note();
note.setTitle(title);
note.setContent(content);
noteList.add(note);
try {
saveNotesToPreferences("add");
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
createNoteView(note);
Toast.makeText(MainActivity.this, "Note saved!", Toast.LENGTH_SHORT).show();
}
});
builder.setNegativeButton("Cancel", (dialogInterface, i) -> dialogInterface.dismiss());
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
private void showEditNoteDialog(Note note){
LayoutInflater inflater = getLayoutInflater();
View dialogView = inflater.inflate(R.layout.create_note_dialog, null);
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setView(dialogView);
builder.setTitle("Edit note");
EditText noteTitleEditText = dialogView.findViewById(R.id.noteTitleEditText);
EditText noteContentEditText = dialogView.findViewById(R.id.noteContentEditText);
noteTitleEditText.setText(note.getTitle());
noteContentEditText.setText(note.getContent());
builder.setPositiveButton("Save", (dialogInterface, i) -> {
String title = noteTitleEditText.getText().toString();
String content = noteContentEditText.getText().toString();
if (!title.isEmpty() && !content.isEmpty()){
try {
deleteNoteAndRefresh(note);
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
note.setTitle(title);
note.setContent(content);
noteList.add(note);
try {
saveNotesToPreferences("add");
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
createNoteView(note);
}else {
Toast.makeText(MainActivity.this, "Enter title and content!", Toast.LENGTH_SHORT).show();
}
});
builder.setNegativeButton("Cancel", (dialogInterface, i) -> dialogInterface.dismiss());
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
private void showDeleteDialog(final Note note){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Delete this note");
builder.setMessage("Are you sure you want to delete it?");
builder.setPositiveButton("Delete", (dialogInterface, i) -> {
try {
deleteNoteAndRefresh(note);
} catch (GeneralSecurityException e) {
throw new RuntimeException(e);
}
});
builder.setNegativeButton("Cancel", null);
builder.show();
}
private boolean validatePassword(String password){
final String PASSWORD_PATTERN = "^(?=.*[0-9])(?=.*[A-Z])(.{8,})$";
Pattern pattern = Pattern.compile(PASSWORD_PATTERN);
Matcher matcher = pattern.matcher(password);
return matcher.matches();
}
private void updatePassword(String hashedEmail, String newPassword) throws InvalidAlgorithmParameterException, NoSuchPaddingException, IllegalBlockSizeException, NoSuchAlgorithmException, InvalidKeySpecException, BadPaddingException, InvalidKeyException {
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_CREDENTIALS, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
byte[] newSalt = Utility.generateSalt();
String newSaltString = Base64.getEncoder().encodeToString(newSalt);
editor.putString("salt_" + hashedEmail, newSaltString);
String hashedNewPassword = Utility.hashCredential(newPassword, newSalt);
editor.putString("user_" + hashedEmail, hashedNewPassword);
editor.apply();
PAS = newPassword;
saveNotesToPreferences("");
}
private boolean validateOldPassword(String hashedEmail, String oldPassword){
byte[] salt = getSaltForUser(hashedEmail, false);
String hashedOldPassword = Utility.hashCredential(oldPassword, salt);
String hashedCorrectPassword = gerPasswordHashFromShared(hashedEmail);
assert hashedOldPassword != null;
return hashedOldPassword.equals(hashedCorrectPassword);
}
private byte[] getSaltForUser(String hashedEmail, boolean salt2){
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_CREDENTIALS, MODE_PRIVATE);
String saltFromData;
if (salt2){
saltFromData = sharedPreferences.getString("salt_2_" + hashedEmail, "err");
}
else {
saltFromData = sharedPreferences.getString("salt_" + hashedEmail, "err");
}
return Base64.getDecoder().decode(saltFromData);
}
private String gerPasswordHashFromShared(String hashedEmail){
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_CREDENTIALS, MODE_PRIVATE);
return sharedPreferences.getString("user_" + hashedEmail, "err");
}
private void saveNotesToPreferences(String mode) throws NoSuchAlgorithmException, InvalidKeySpecException, InvalidAlgorithmParameterException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException, InvalidKeyException {
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_NOTES, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
if (mode.equals("del")){
int noteCount = sharedPreferences.getInt("notecount_"+HASHED_EMAIL, 0);
for(int i=0; i<noteCount; i++){
editor.remove(i + "_title_" + HASHED_EMAIL);
editor.remove(i + "_content_" + HASHED_EMAIL);
}
}
//tutaj muszę wygenerować randomowy iv. Używam go do enkrypcji i zapisuje do shared jako string
IvParameterSpec iv = UtilityAES.generateIv();
String ivString = ivToString(iv);
saveIvStringToShared(ivString);
editor.putInt("notecount_" + HASHED_EMAIL, noteList.size());
for(int i=0; i<noteList.size(); i++){
Note note = noteList.get(i);
editor.putString(i + "_title_" + HASHED_EMAIL, UtilityAES.encrypt("AES/CBC/PKCS5Padding", note.getTitle(), UtilityAES.getKeyFromPassword(PAS, getSaltForUser(HASHED_EMAIL, true)), iv));
editor.putString(i + "_content_" + HASHED_EMAIL, UtilityAES.encrypt("AES/CBC/PKCS5Padding", note.getContent(), UtilityAES.getKeyFromPassword(PAS, getSaltForUser(HASHED_EMAIL, true)), iv));
}
editor.apply();
}
private void loadNotesFromPreferencesToList() throws NoSuchAlgorithmException, InvalidKeySpecException, InvalidAlgorithmParameterException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException, InvalidKeyException {
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_NOTES, MODE_PRIVATE);
int noteCount = sharedPreferences.getInt("notecount_" + HASHED_EMAIL, 0);
//tutaj muszę pobrać iv z shared i skonvertować do dobrego formatu
String ivString = getIVStringFromShared();
IvParameterSpec iv = stringToIv(ivString);
for(int i=0; i<noteCount; i++){
String title = sharedPreferences.getString(i + "_title_" + HASHED_EMAIL, "");
String content = sharedPreferences.getString(i + "_content_" + HASHED_EMAIL, "");
Note note = new Note();
note.setTitle(UtilityAES.decrypt("AES/CBC/PKCS5Padding", title, UtilityAES.getKeyFromPassword(PAS, getSaltForUser(HASHED_EMAIL, true)), iv) );
note.setContent(UtilityAES.decrypt("AES/CBC/PKCS5Padding", content, UtilityAES.getKeyFromPassword(PAS, getSaltForUser(HASHED_EMAIL, true)), iv) );
noteList.add(note);
}
}
private void saveIvStringToShared(String ivString){
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_NOTES, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("iv_" + HASHED_EMAIL, ivString);
editor.apply();
}
private String getIVStringFromShared(){
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_NAME_NOTES, MODE_PRIVATE);
return sharedPreferences.getString("iv_" + HASHED_EMAIL, "err");
}
private static IvParameterSpec stringToIv(String ivString) {
byte[] ivBytes = Base64.getDecoder().decode(ivString);
return new IvParameterSpec(ivBytes);
}
private static String ivToString(IvParameterSpec ivParameterSpec) {
byte[] ivBytes = ivParameterSpec.getIV();
return Base64.getEncoder().encodeToString(ivBytes);
}
private void createNoteView(final Note note){
@SuppressLint("InflateParams") View noteView = getLayoutInflater().inflate(R.layout.note_item, null);
TextView noteTitleTextView = noteView.findViewById(R.id.noteTitleTextView);
TextView noteContentTextView = noteView.findViewById(R.id.noteContentTextView);
Button deleteNoteButton = noteView.findViewById(R.id.btnDeleteNote);
noteTitleTextView.setText(note.getTitle());
noteContentTextView.setText(note.getContent());
deleteNoteButton.setOnClickListener(view -> showDeleteDialog(note));
noteView.setOnLongClickListener(view -> {
showEditNoteDialog(note);
return true;
});
notesContainer.addView(noteView);
}
private void deleteNoteAndRefresh(Note note) throws InvalidAlgorithmParameterException, NoSuchPaddingException, IllegalBlockSizeException, NoSuchAlgorithmException, InvalidKeySpecException, BadPaddingException, InvalidKeyException {
noteList.remove(note);
saveNotesToPreferences("del");
refreshNotesView();
}
private void refreshNotesView(){
notesContainer.removeAllViews();
displayNotes();
}
private void displayNotes(){
for(Note note : noteList){
createNoteView(note);
}
}
}