diff options
Diffstat (limited to 'OpenPGP-Keychain/src/main/java/org/sufficientlysecure/keychain/remote/RemoteService.java')
-rw-r--r-- | OpenPGP-Keychain/src/main/java/org/sufficientlysecure/keychain/remote/RemoteService.java | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/OpenPGP-Keychain/src/main/java/org/sufficientlysecure/keychain/remote/RemoteService.java b/OpenPGP-Keychain/src/main/java/org/sufficientlysecure/keychain/remote/RemoteService.java new file mode 100644 index 000000000..7e935d317 --- /dev/null +++ b/OpenPGP-Keychain/src/main/java/org/sufficientlysecure/keychain/remote/RemoteService.java @@ -0,0 +1,258 @@ +/* + * Copyright (C) 2013-2014 Dominik Schürmann <dominik@dominikschuermann.de> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +package org.sufficientlysecure.keychain.remote; + +import android.app.PendingIntent; +import android.app.Service; +import android.content.Context; +import android.content.Intent; +import android.content.pm.PackageInfo; +import android.content.pm.PackageManager; +import android.content.pm.PackageManager.NameNotFoundException; +import android.content.pm.Signature; +import android.net.Uri; +import android.os.Binder; + +import org.openintents.openpgp.OpenPgpError; +import org.openintents.openpgp.util.OpenPgpApi; +import org.sufficientlysecure.keychain.Constants; +import org.sufficientlysecure.keychain.R; +import org.sufficientlysecure.keychain.provider.KeychainContract; +import org.sufficientlysecure.keychain.provider.ProviderHelper; +import org.sufficientlysecure.keychain.remote.ui.RemoteServiceActivity; +import org.sufficientlysecure.keychain.util.Log; + +import java.util.ArrayList; +import java.util.Arrays; + +/** + * Abstract service class for remote APIs that handle app registration and user input. + */ +public abstract class RemoteService extends Service { + Context mContext; + + private static final int PRIVATE_REQUEST_CODE_REGISTER = 651; + private static final int PRIVATE_REQUEST_CODE_ERROR = 652; + + public Context getContext() { + return mContext; + } + + protected Intent isAllowed(Intent data) { + try { + if (isCallerAllowed(false)) { + return null; + } else { + String packageName = getCurrentCallingPackage(); + + byte[] packageSignature; + try { + packageSignature = getPackageSignature(packageName); + } catch (NameNotFoundException e) { + Log.e(Constants.TAG, "Should not happen, returning!", e); + // return error + Intent result = new Intent(); + result.putExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR); + result.putExtra(OpenPgpApi.RESULT_ERROR, + new OpenPgpError(OpenPgpError.GENERIC_ERROR, e.getMessage())); + return result; + } + Log.e(Constants.TAG, "Not allowed to use service! return PendingIntent for registration!"); + + Intent intent = new Intent(getBaseContext(), RemoteServiceActivity.class); + intent.setAction(RemoteServiceActivity.ACTION_REGISTER); + intent.putExtra(RemoteServiceActivity.EXTRA_PACKAGE_NAME, packageName); + intent.putExtra(RemoteServiceActivity.EXTRA_PACKAGE_SIGNATURE, packageSignature); + intent.putExtra(RemoteServiceActivity.EXTRA_DATA, data); + + PendingIntent pi = PendingIntent.getActivity(getBaseContext(), + PRIVATE_REQUEST_CODE_REGISTER, intent, 0); + + // return PendingIntent to be executed by client + Intent result = new Intent(); + result.putExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED); + result.putExtra(OpenPgpApi.RESULT_INTENT, pi); + + return result; + } + } catch (WrongPackageSignatureException e) { + Log.e(Constants.TAG, "wrong signature!", e); + + Intent intent = new Intent(getBaseContext(), RemoteServiceActivity.class); + intent.setAction(RemoteServiceActivity.ACTION_ERROR_MESSAGE); + intent.putExtra(RemoteServiceActivity.EXTRA_ERROR_MESSAGE, + getString(R.string.api_error_wrong_signature)); + intent.putExtra(RemoteServiceActivity.EXTRA_DATA, data); + + PendingIntent pi = PendingIntent.getActivity(getBaseContext(), + PRIVATE_REQUEST_CODE_ERROR, intent, 0); + + // return PendingIntent to be executed by client + Intent result = new Intent(); + result.putExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED); + result.putExtra(OpenPgpApi.RESULT_INTENT, pi); + + return result; + } + } + + private byte[] getPackageSignature(String packageName) throws NameNotFoundException { + PackageInfo pkgInfo = getPackageManager().getPackageInfo(packageName, + PackageManager.GET_SIGNATURES); + Signature[] signatures = pkgInfo.signatures; + // TODO: Only first signature?! + byte[] packageSignature = signatures[0].toByteArray(); + + return packageSignature; + } + + /** + * Returns package name associated with the UID, which is assigned to the process that sent you the + * current transaction that is being processed :) + * + * @return package name + */ + private String getCurrentCallingPackage() { + // TODO: + // callingPackages contains more than one entry when sharedUserId has been used... + String[] callingPackages = getPackageManager().getPackagesForUid(Binder.getCallingUid()); + String currentPkg = callingPackages[0]; + Log.d(Constants.TAG, "currentPkg: " + currentPkg); + + return currentPkg; + } + + /** + * Retrieves AccountSettings from database for the application calling this remote service + * + * @return + */ + protected AccountSettings getAccSettings(String accountName) { + String currentPkg = getCurrentCallingPackage(); + Log.d(Constants.TAG, "accountName: " + accountName); + + Uri uri = KeychainContract.ApiAccounts.buildByPackageAndAccountUri(currentPkg, accountName); + + AccountSettings settings = ProviderHelper.getApiAccountSettings(this, uri); + + return settings; // can be null! + } + + protected Intent getCreateAccountIntent(Intent data, String accountName) { + String packageName = getCurrentCallingPackage(); + Log.d(Constants.TAG, "accountName: " + accountName); + + Intent intent = new Intent(getBaseContext(), RemoteServiceActivity.class); + intent.setAction(RemoteServiceActivity.ACTION_CREATE_ACCOUNT); + intent.putExtra(RemoteServiceActivity.EXTRA_PACKAGE_NAME, packageName); + intent.putExtra(RemoteServiceActivity.EXTRA_ACC_NAME, accountName); + intent.putExtra(RemoteServiceActivity.EXTRA_DATA, data); + + PendingIntent pi = PendingIntent.getActivity(getBaseContext(), + PRIVATE_REQUEST_CODE_REGISTER, intent, 0); + + // return PendingIntent to be executed by client + Intent result = new Intent(); + result.putExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_USER_INTERACTION_REQUIRED); + result.putExtra(OpenPgpApi.RESULT_INTENT, pi); + + return result; + } + + /** + * Checks if process that binds to this service (i.e. the package name corresponding to the + * process) is in the list of allowed package names. + * + * @param allowOnlySelf allow only Keychain app itself + * @return true if process is allowed to use this service + * @throws WrongPackageSignatureException + */ + private boolean isCallerAllowed(boolean allowOnlySelf) throws WrongPackageSignatureException { + return isUidAllowed(Binder.getCallingUid(), allowOnlySelf); + } + + private boolean isUidAllowed(int uid, boolean allowOnlySelf) + throws WrongPackageSignatureException { + if (android.os.Process.myUid() == uid) { + return true; + } + if (allowOnlySelf) { // barrier + return false; + } + + String[] callingPackages = getPackageManager().getPackagesForUid(uid); + + // is calling package allowed to use this service? + for (int i = 0; i < callingPackages.length; i++) { + String currentPkg = callingPackages[i]; + + if (isPackageAllowed(currentPkg)) { + return true; + } + } + + Log.d(Constants.TAG, "Caller is NOT allowed!"); + return false; + } + + /** + * Checks if packageName is a registered app for the API. Does not return true for own package! + * + * @param packageName + * @return + * @throws WrongPackageSignatureException + */ + private boolean isPackageAllowed(String packageName) throws WrongPackageSignatureException { + Log.d(Constants.TAG, "packageName: " + packageName); + + ArrayList<String> allowedPkgs = ProviderHelper.getRegisteredApiApps(this); + Log.d(Constants.TAG, "allowed: " + allowedPkgs); + + // check if package is allowed to use our service + if (allowedPkgs.contains(packageName)) { + Log.d(Constants.TAG, "Package is allowed! packageName: " + packageName); + + // check package signature + byte[] currentSig; + try { + currentSig = getPackageSignature(packageName); + } catch (NameNotFoundException e) { + throw new WrongPackageSignatureException(e.getMessage()); + } + + byte[] storedSig = ProviderHelper.getApiAppSignature(this, packageName); + if (Arrays.equals(currentSig, storedSig)) { + Log.d(Constants.TAG, + "Package signature is correct! (equals signature from database)"); + return true; + } else { + throw new WrongPackageSignatureException( + "PACKAGE NOT ALLOWED! Signature wrong! (Signature not equals signature from database)"); + } + } + + return false; + } + + @Override + public void onCreate() { + super.onCreate(); + mContext = this; + } + +} |