KeyStoreManager.java

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.motorolamobility.studio.android.certmanager.core;

import java.io.File;
import java.io.IOException;
import java.security.KeyStore;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import com.motorola.studio.android.common.log.StudioLogger;
import com.motorolamobility.studio.android.certmanager.exception.InvalidPasswordException;
import com.motorolamobility.studio.android.certmanager.exception.KeyStoreManagerException;
import com.motorolamobility.studio.android.certmanager.ui.model.IKeyStore;
import com.motorolamobility.studio.android.certmanager.ui.model.KeyStoreNode;
import com.motorolamobility.studio.android.certmanager.ui.model.KeyStoreRootNode;
import com.motorolamobility.studio.android.certmanager.views.KeystoreManagerView;

/**
 * Provides a common interface to manipulate keystores.
 * Other plugins need to use it (to avoid knowing {@link KeyStoreRootNode} model and {@link SaveStateManager}).
 * 
 * The {@link KeystoreManagerView} also need to call its methods to guarantee persistence of its operations. 
 */
public class KeyStoreManager
{
    public static final String KEYSTORE_TYPE_PKCS12 = "PKCS12";

    public static final String KEYSTORE_TYPE_JCEKS = "JCEKS";

    public static final String KEYSTORE_TYPE_JKS = "JKS";

    private static final String ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE =
            "Error to access keystore mapping persistence";

    private static KeyStoreManager _instance;

    private List<IKeyStore> keyStores = null;

    /**
     * This class is a singleton.
     * @return The unique instance of this class.
     * */
    public synchronized static KeyStoreManager getInstance()
    {
        if (_instance == null)
        {
            _instance = new KeyStoreManager();
        }
        return _instance;
    }

    private KeyStoreManager()
    {
    }

    /**
     * Add a new keystore to the manager.
     * @param keystore The keystore to be added.
     * @throws KeyStoreManagerException if an error occurs while accessing persistence file where keystores are mapped. 
     */
    public void addKeyStore(IKeyStore keystore) throws KeyStoreManagerException
    {
        SaveStateManager manager = null;
        try
        {
            manager = SaveStateManager.getInstance();
            manager.addEntry(keystore.getFile(), keystore.getType());
            getKeyStores().add(keystore);
        }
        catch (Exception e)
        {
            throw new KeyStoreManagerException(ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE, e);
        }
    }

    /**
     * Remove a keystore from the manager. 
     * @param keystore The keystore to be removed.
     * @throws KeyStoreManagerException if an error occurs while accessing persistence file where keystores are mapped. 
     */
    public void removeKeyStore(IKeyStore keystore) throws KeyStoreManagerException
    {
        SaveStateManager manager = null;
        try
        {
            manager = SaveStateManager.getInstance();
            manager.removeEntry(keystore.getFile());
            getKeyStores().remove(keystore);
        }
        catch (Exception e)
        {
            throw new KeyStoreManagerException(ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE, e);
        }
    }

    /**
     * Set the date which the keystore was added to a backup file.
     * @param keyStore The keystore to be set.
     * @param backupDate The date of the backup. 
     * @throws KeyStoreManagerException If there were problems while persisting the information.
     * */
    public void setBackupDate(IKeyStore keyStore, Date backupDate) throws KeyStoreManagerException
    {
        if ((keyStore != null) && (backupDate != null))
        {
            try
            {
                SaveStateManager manager = SaveStateManager.getInstance();
                manager.setBackupDate(keyStore.getFile(), backupDate);
            }
            catch (Exception e)
            {
                throw new KeyStoreManagerException(ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE, e);
            }
        }
    }

    /**
     * Update the type of a managed keystore, using solely the information provided by the keystore. 
     * @param keystore The keystore which type needs to be updated.
     * @throws KeyStoreManagerException If there were problems while persisting the information.
     * */
    public void updateKeyStoreType(IKeyStore keyStore) throws KeyStoreManagerException
    {
        SaveStateManager manager;
        try
        {
            manager = SaveStateManager.getInstance();
            if (manager.isKeystoreMapped(keyStore.getFile()))
            {
                manager.addEntry(keyStore.getFile(), keyStore.getType());
            }
        }
        catch (IOException e)
        {
            throw new KeyStoreManagerException(ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE, e);
        }

    }

    /**
     * @return The list of mapped keystores in the persistence, or empty list if there is no keystore mapped.
     * @throws KeyStoreManagerException if an error occurs to access persistence file where keystores are mapped. 
     */
    public List<IKeyStore> getKeyStores() throws KeyStoreManagerException
    {
        if (keyStores == null)
        {
            keyStores = new ArrayList<IKeyStore>();
            SaveStateManager manager = null;
            try
            {
                manager = SaveStateManager.getInstance();
                if (manager.getMappedKeystores() != null)
                {
                    for (File keystoreFile : manager.getMappedKeystores())
                    {
                        SaveStateManager.ViewStateEntry stateEntry = manager.getEntry(keystoreFile);
                        if (stateEntry != null)
                        {
                            IKeyStore keyStoreNode = new KeyStoreNode(keystoreFile);
                            keyStoreNode.setType(stateEntry.getKeystoreType());
                            keyStoreNode.setLastBackupDate(stateEntry.getBackupDate());
                            keyStores.add(keyStoreNode);
                        }
                    }
                }
            }
            catch (IOException e)
            {
                throw new KeyStoreManagerException(ERROR_TO_ACCESS_KEYSTORE_MAPPING_PERSISTENCE, e);
            }
        }
        return keyStores;
    }

    /**
     * Check if a keystore file is already mapped.
     * The input parameter is a File, instead of a String, to ensure that File.getCanonicalPath() will be used in the filenames comparison.
     * @param keystoreFile A file representing the keystore.
     * @return True if the file is already mapped, false otherwise.   
     * */
    public boolean isKeystoreMapped(File keystoreFile)
    {
        boolean result = false;
        SaveStateManager manager = null;

        try
        {
            manager = SaveStateManager.getInstance();
            if (manager.getMappedKeystores() != null)
            {
                for (File mappedKeystoreFile : manager.getMappedKeystores())
                {
                    if (mappedKeystoreFile.getCanonicalPath().equals(
                            keystoreFile.getCanonicalPath()))
                    {
                        result = true;
                        break;
                    }
                }
            }
        }
        catch (IOException e)
        {
            result = false;
            StudioLogger
                    .error(getClass(),
                            "IOException while trying to check if a file is mapped on Signing and Keys view.");
        }

        return result;
    }

    /**
     * The current available keystore types are:
     * <ul>
     * <li>JKS</li>
     * <li>JCEKS</li>
     * <li>PKCS12</li>
     * </ul> 
     * @return The list of available keystore types.
     * */
    public List<String> getAvailableTypes()
    {
        List<String> availableKeystoreTypes = new ArrayList<String>();

        availableKeystoreTypes.add(KEYSTORE_TYPE_JKS);
        availableKeystoreTypes.add(KEYSTORE_TYPE_JCEKS);
        availableKeystoreTypes.add(KEYSTORE_TYPE_PKCS12);

        if (!availableKeystoreTypes.contains(getDefaultType()))
        {
            availableKeystoreTypes.add(getDefaultType());
        }

        return availableKeystoreTypes;
    }

    /**
     * When no store type is specified, the manager define a type that should be used as the default one.
     * @return The default keystore type used in the Signing and Keys view.
     * */
    public String getDefaultType()
    {
        return KeyStore.getDefaultType().toUpperCase();
    }

    /**
     * Create a new keystore given a file, a store type and a password.
     */
    public static IKeyStore createKeyStore(File keyStoreFile, String keyStoreType, char[] password)
            throws KeyStoreManagerException
    {
        IKeyStore keyStoreNode = null;
        try
        {
            KeyStore keyStore = KeyStoreUtils.createKeystore(keyStoreFile, keyStoreType, password);
            keyStoreNode = new KeyStoreNode(keyStoreFile, keyStore);
        }
        catch (InvalidPasswordException e)
        {
            StudioLogger.error("Invalid password when creating a keystore: " + e.getMessage());
        }
        return keyStoreNode;
    }

    /**
     * Create a new keystore given a file and a password.
     * The store type is set to be the default.
     */
    public static IKeyStore createKeyStore(File keyStoreFile, char[] password)
            throws KeyStoreManagerException
    {
        IKeyStore keyStoreNode = null;
        try
        {
            KeyStore keyStore = KeyStoreUtils.createKeystore(keyStoreFile, password);
            keyStoreNode = new KeyStoreNode(keyStoreFile, keyStore);
        }
        catch (InvalidPasswordException e)
        {
            StudioLogger.error("Invalid password when creating a keystore: " + e.getMessage());
        }

        return keyStoreNode;
    }
}