Synnefo » Pithos Android Client

package com.rackspacecloud.android;

import java.security.MessageDigest;

import java.security.NoSuchAlgorithmException;

import java.util.Arrays;

import android.content.SharedPreferences;

public class PasswordManager {

        private SharedPreferences settings;

        public PasswordManager(SharedPreferences sp) {

                settings = sp;

        }

        /*

         * checks the parameter string against the stored password

         */

        public boolean verifyEnteredPassword(String password) {

                return Arrays.toString(getHash(password)).equals(getStoredPassword());

        }

        /*

         * return the hash of the password that is stored in shared preferences

         */

        private String getStoredPassword() {

                return settings.getString(Preferences.PREF_KEY_PASSCODE_HASH, "");

        }

        /*

         * turns off password requirement

         */

        public void turnOffPassword() {

                SharedPreferences.Editor editor = settings.edit();

                editor.putString(Preferences.PREF_KEY_PASSCODE_HASH, "");

                editor.putBoolean(Preferences.PREF_KEY_PASSWORD_LOCK, false);

                editor.commit();

        }

        /*

         * submits a password change into memory stores the sha-256 hash of the

         * password

         */

        private void storeNewPassword(String hashedPassword) {

                SharedPreferences.Editor editor = settings.edit();

                editor.putString(Preferences.PREF_KEY_PASSCODE_HASH, hashedPassword);

                editor.putBoolean(Preferences.PREF_KEY_PASSWORD_LOCK, true);

                editor.commit();

        }

        /*

         * changes the password for

         */

        public void changePassword(String password) {

                storeNewPassword(Arrays.toString(getHash(password)));

        }

        /*

         * returns the sha-256 hash for a given string

         */

        private byte[] getHash(String password) {

                MessageDigest m = null;

                try {

                        m = MessageDigest.getInstance("SHA-256");

                        m.update(password.getBytes());

                } catch (NoSuchAlgorithmException e) {

                        // TODO Auto-generated catch block

                        e.printStackTrace();

                } catch (NullPointerException e) {

                        // TODO Auto-generated catch block

                        e.printStackTrace();

                }

                return m.digest();

        }

        /*

         * returns true if their is a password requirement

         */

        public boolean hasPassword() {

                return settings.getBoolean(Preferences.PREF_KEY_PASSWORD_LOCK, false);

        }

}