Java tutorial
/* * 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 android.os; import android.annotation.UnsupportedAppUsage; import android.util.Slog; import java.io.File; import java.io.FileDescriptor; import java.io.IOException; /** * This class provides access to the centralized jni bindings for * SELinux interaction. * {@hide} */ public class SELinux { private static final String TAG = "SELinux"; /** Keep in sync with ./external/selinux/libselinux/include/selinux/android.h */ private static final int SELINUX_ANDROID_RESTORECON_NOCHANGE = 1; private static final int SELINUX_ANDROID_RESTORECON_VERBOSE = 2; private static final int SELINUX_ANDROID_RESTORECON_RECURSE = 4; private static final int SELINUX_ANDROID_RESTORECON_FORCE = 8; private static final int SELINUX_ANDROID_RESTORECON_DATADATA = 16; private static final int SELINUX_ANDROID_RESTORECON_SKIPCE = 32; private static final int SELINUX_ANDROID_RESTORECON_CROSS_FILESYSTEMS = 64; private static final int SELINUX_ANDROID_RESTORECON_SKIP_SEHASH = 128; /** * Determine whether SELinux is disabled or enabled. * @return a boolean indicating whether SELinux is enabled. */ @UnsupportedAppUsage public static final native boolean isSELinuxEnabled(); /** * Determine whether SELinux is permissive or enforcing. * @return a boolean indicating whether SELinux is enforcing. */ @UnsupportedAppUsage public static final native boolean isSELinuxEnforced(); /** * Sets the security context for newly created file objects. * @param context a security context given as a String. * @return a boolean indicating whether the operation succeeded. */ public static final native boolean setFSCreateContext(String context); /** * Change the security context of an existing file object. * @param path representing the path of file object to relabel. * @param context new security context given as a String. * @return a boolean indicating whether the operation succeeded. */ public static final native boolean setFileContext(String path, String context); /** * Get the security context of a file object. * @param path the pathname of the file object. * @return a security context given as a String. */ @UnsupportedAppUsage public static final native String getFileContext(String path); /** * Get the security context of a peer socket. * @param fd FileDescriptor class of the peer socket. * @return a String representing the peer socket security context. */ public static final native String getPeerContext(FileDescriptor fd); /** * Get the security context of a file descriptor of a file. * @param fd FileDescriptor of a file. * @return a String representing the file descriptor security context. */ public static final native String getFileContext(FileDescriptor fd); /** * Gets the security context of the current process. * @return a String representing the security context of the current process. */ @UnsupportedAppUsage public static final native String getContext(); /** * Gets the security context of a given process id. * @param pid an int representing the process id to check. * @return a String representing the security context of the given pid. */ @UnsupportedAppUsage public static final native String getPidContext(int pid); /** * Check permissions between two security contexts. * @param scon The source or subject security context. * @param tcon The target or object security context. * @param tclass The object security class name. * @param perm The permission name. * @return a boolean indicating whether permission was granted. */ @UnsupportedAppUsage public static final native boolean checkSELinuxAccess(String scon, String tcon, String tclass, String perm); /** * Restores a file to its default SELinux security context. * If the system is not compiled with SELinux, then {@code true} * is automatically returned. * If SELinux is compiled in, but disabled, then {@code true} is * returned. * * @param pathname The pathname of the file to be relabeled. * @return a boolean indicating whether the relabeling succeeded. * @exception NullPointerException if the pathname is a null object. */ public static boolean restorecon(String pathname) throws NullPointerException { if (pathname == null) { throw new NullPointerException(); } return native_restorecon(pathname, 0); } /** * Restores a file to its default SELinux security context. * If the system is not compiled with SELinux, then {@code true} * is automatically returned. * If SELinux is compiled in, but disabled, then {@code true} is * returned. * * @param pathname The pathname of the file to be relabeled. * @return a boolean indicating whether the relabeling succeeded. */ private static native boolean native_restorecon(String pathname, int flags); /** * Restores a file to its default SELinux security context. * If the system is not compiled with SELinux, then {@code true} * is automatically returned. * If SELinux is compiled in, but disabled, then {@code true} is * returned. * * @param file The File object representing the path to be relabeled. * @return a boolean indicating whether the relabeling succeeded. * @exception NullPointerException if the file is a null object. */ public static boolean restorecon(File file) throws NullPointerException { try { return native_restorecon(file.getCanonicalPath(), 0); } catch (IOException e) { Slog.e(TAG, "Error getting canonical path. Restorecon failed for " + file.getPath(), e); return false; } } /** * Recursively restores all files under the given path to their default * SELinux security context. If the system is not compiled with SELinux, * then {@code true} is automatically returned. If SELinux is compiled in, * but disabled, then {@code true} is returned. * * @return a boolean indicating whether the relabeling succeeded. */ @UnsupportedAppUsage public static boolean restoreconRecursive(File file) { try { return native_restorecon(file.getCanonicalPath(), SELINUX_ANDROID_RESTORECON_RECURSE | SELINUX_ANDROID_RESTORECON_SKIP_SEHASH); } catch (IOException e) { Slog.e(TAG, "Error getting canonical path. Restorecon failed for " + file.getPath(), e); return false; } } }