chattr -i for log directory (#1398)

Co-authored-by: Howard Wu <40033067+Howard20181@users.noreply.github.com>

core/src/main/cpp/main/src/context.cpp

@@ -31,6 +31,11 @@
 #include "service.h"
 #include "symbol_cache.h"
 
+#include <linux/fs.h>
+#include <fcntl.h>
+
+static_assert(FS_IOC_SETFLAGS == LP_SELECT(0x40046602, 0x40086602));
+
 namespace lspd {
     extern int *allowUnload;
 

core/src/main/java/org/lsposed/lspd/service/ConfigFileManager.java

@@ -9,6 +9,7 @@ import android.os.ParcelFileDescriptor;
 import android.os.SELinux;
 import android.os.SharedMemory;
 import android.system.ErrnoException;
+import android.system.Os;
 import android.system.OsConstants;
 import android.util.Log;
 
@@ -45,6 +46,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.zip.ZipFile;
 
+import hidden.HiddenApiBridge;
+
 public class ConfigFileManager {
     static final Path basePath = Paths.get("/data/adb/lspd");
     static final Path managerApkPath = basePath.resolve("manager.apk");
@@ -144,11 +147,25 @@ public class ConfigFileManager {
         });
     }
 
+    public static boolean chattr0(Path path) {
+        try {
+            var dir = Os.open(path.toAbsolutePath().toString(), OsConstants.O_RDONLY, 0);
+            HiddenApiBridge.Os_ioctlInt(dir, HiddenApiBridge.VMRuntime_is64Bit() ? 0x40086602 : 0x40046602, 0);
+            Os.close(dir);
+            return true;
+        } catch (Throwable e) {
+            Log.d(TAG, "chattr 0", e);
+            return false;
+        }
+    }
+
     static void moveLogDir() {
         try {
             if (Files.exists(logDirPath)) {
-                deleteFolderIfExists(oldLogDirPath);
+                if (chattr0(logDirPath)) {
-                Files.move(logDirPath, oldLogDirPath);
+                    deleteFolderIfExists(oldLogDirPath);
+                    Files.move(logDirPath, oldLogDirPath);
+                }
             }
             Files.createDirectories(logDirPath);
         } catch (IOException e) {

core/src/main/java/org/lsposed/lspd/service/LogcatService.java

@@ -11,6 +11,7 @@ import org.lsposed.lspd.BuildConfig;
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.File;
+import java.io.FileDescriptor;
 import java.io.FileOutputStream;
 import java.io.FileWriter;
 import java.io.IOException;
@@ -19,7 +20,6 @@ import java.nio.file.Files;
 import java.nio.file.LinkOption;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.Arrays;
 
 public class LogcatService implements Runnable {
     private static final String TAG = "LSPosedLogcat";
@@ -27,8 +27,8 @@ public class LogcatService implements Runnable {
             ParcelFileDescriptor.MODE_CREATE |
             ParcelFileDescriptor.MODE_TRUNCATE |
             ParcelFileDescriptor.MODE_APPEND;
-    private Path modulesLog = null;
+    private int modulesFd = -1;
-    private Path verboseLog = null;
+    private int verboseFd = -1;
     private Thread thread = null;
 
     @SuppressLint("UnsafeDynamicallyLoadedCode")
@@ -56,42 +56,45 @@ public class LogcatService implements Runnable {
         try {
             File log;
             if (isVerboseLog) {
-                checkFdFile(verboseLog);
+                checkFd(verboseFd);
                 log = ConfigFileManager.getNewVerboseLogPath();
             } else {
-                checkFdFile(modulesLog);
+                checkFd(modulesFd);
                 log = ConfigFileManager.getNewModulesLogPath();
             }
             Log.i(TAG, "New log file: " + log);
+            ConfigFileManager.chattr0(log.toPath().getParent());
             int fd = ParcelFileDescriptor.open(log, mode).detachFd();
-            var fdFile = Paths.get("/proc/self/fd", String.valueOf(fd));
+            if (isVerboseLog) verboseFd = fd;
-            if (isVerboseLog) verboseLog = fdFile;
+            else modulesFd = fd;
-            else modulesLog = fdFile;
             return fd;
         } catch (IOException e) {
-            if (isVerboseLog) verboseLog = null;
+            if (isVerboseLog) verboseFd = -1;
-            else modulesLog = null;
+            else modulesFd = -1;
             Log.w(TAG, "refreshFd", e);
             return -1;
         }
     }
 
-    private static void checkFdFile(Path fdFile) {
+    private static void checkFd(int fd) {
-        if (fdFile == null) return;
+        if (fd == -1) return;
         try {
-            var file = Files.readSymbolicLink(fdFile);
+            var jfd = new FileDescriptor();
-            if (!Files.exists(file)) {
+            jfd.getClass().getDeclaredMethod("setInt$", int.class).invoke(jfd, fd);
+            var stat = Os.fstat(jfd);
+            if (stat.st_nlink == 0) {
+                var file = Files.readSymbolicLink(fdToPath(fd));
                 var parent = file.getParent();
                 if (!Files.isDirectory(parent, LinkOption.NOFOLLOW_LINKS)) {
-                    Files.deleteIfExists(parent);
+                    if (ConfigFileManager.chattr0(parent))
+                        Files.deleteIfExists(parent);
                 }
-                Files.createDirectories(parent);
                 var name = file.getFileName().toString();
                 var originName = name.substring(0, name.lastIndexOf(' '));
-                Files.copy(fdFile, parent.resolve(originName));
+                Files.copy(file, parent.resolve(originName));
             }
-        } catch (IOException e) {
+        } catch (Throwable e) {
-            Log.w(TAG, "checkFd " + fdFile, e);
+            Log.w(TAG, "checkFd " + fd, e);
         }
     }
 
@@ -133,7 +136,7 @@ public class LogcatService implements Runnable {
                         }
                     }
                 } catch (IOException e) {
-                    Log.e(TAG, "GetProp: " + e + ": " + Arrays.toString(e.getStackTrace()));
+                    Log.e(TAG, "GetProp: ", e);
                 }
             });
             t.start();
@@ -143,7 +146,7 @@ public class LogcatService implements Runnable {
                 writer.append(sb);
             }
         } catch (IOException | InterruptedException | NullPointerException e) {
-            Log.e(TAG, "GetProp: " + Arrays.toString(e.getStackTrace()));
+            Log.e(TAG, "GetProp: ", e);
         }
     }
 
@@ -163,24 +166,25 @@ public class LogcatService implements Runnable {
         }
     }
 
+    static private Path fdToPath(int fd) {
+        if (fd == -1) return null;
+        else return Paths.get("/proc/self/fd", String.valueOf(fd));
+    }
+
     public File getVerboseLog() {
-        return verboseLog.toFile();
+        var path = fdToPath(verboseFd);
+        return path == null ? null : path.toFile();
     }
 
     public File getModulesLog() {
-        return modulesLog.toFile();
+        var path = fdToPath(modulesFd);
+        return path == null ? null : path.toFile();
     }
 
     public void checkLogFile() {
-        try {
+        if (modulesFd == -1)
-            modulesLog.toRealPath();
-        } catch (IOException e) {
             refresh(false);
-        }
+        if (verboseFd == -1)
-        try {
-            verboseLog.toRealPath();
-        } catch (IOException e) {
             refresh(true);
-        }
     }
 }

hiddenapi-bridge/src/main/java/hidden/HiddenApiBridge.java

@@ -30,12 +30,20 @@ import android.content.res.CompatibilityInfo;
 import android.content.res.Resources;
 import android.content.res.ResourcesImpl;
 import android.os.Binder;
+import android.os.Build;
 import android.os.Environment;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.UserHandle;
+import android.system.ErrnoException;
+import android.system.Int32Ref;
+import android.system.Os;
+import android.util.MutableInt;
 
 import java.io.File;
+import java.io.FileDescriptor;
+
+import dalvik.system.VMRuntime;
 
 public class HiddenApiBridge {
     public static int AssetManager_addAssetPath(AssetManager am, String path) {
@@ -91,4 +99,18 @@ public class HiddenApiBridge {
     public static CompatibilityInfo Resources_getCompatibilityInfo(Resources res) {
         return res.getCompatibilityInfo();
     }
+
+    public static int Os_ioctlInt(FileDescriptor fd, int cmd, int arg) throws ErrnoException {
+        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1) {
+            return Os.ioctlInt(fd, cmd, new MutableInt(arg));
+        } else if (Build.VERSION.SDK_INT < Build.VERSION_CODES.S) {
+            return Os.ioctlInt(fd, cmd, new Int32Ref(arg));
+        } else {
+            return Os.ioctlInt(fd, cmd);
+        }
+    }
+
+    public static boolean VMRuntime_is64Bit() {
+        return VMRuntime.getRuntime().is64Bit();
+    }
 }

hiddenapi-stubs/src/main/java/android/os/Build.java

@@ -0,0 +1,15 @@
+package android.os;
+
+public class Build {
+    public static class VERSION {
+        public final static int SDK_INT = SystemProperties.getInt(
+                "ro.build.version.sdk", 0);
+    }
+    public static class VERSION_CODES {
+        public static final int O_MR1 = 27;
+        public static final int P = 28;
+        public static final int Q = 29;
+        public static final int R = 30;
+        public static final int S = 31;
+    }
+}

hiddenapi-stubs/src/main/java/android/system/ErrnoException.java

@@ -0,0 +1,5 @@
+package android.system;
+
+public final class ErrnoException extends Exception {
+
+}

hiddenapi-stubs/src/main/java/android/system/Int32Ref.java

@@ -0,0 +1,15 @@
+package android.system;
+
+import java.util.Objects;
+
+public class Int32Ref {
+    public int value;
+
+    public Int32Ref(int value) {
+        this.value = value;
+    }
+
+    @Override public String toString() {
+        return Objects.toString(this);
+    }
+}

hiddenapi-stubs/src/main/java/android/system/Os.java

@@ -0,0 +1,23 @@
+package android.system;
+
+import android.util.MutableInt;
+
+import androidx.annotation.RequiresApi;
+
+import java.io.FileDescriptor;
+
+public class Os {
+    public static int ioctlInt(FileDescriptor fd, int cmd, MutableInt arg) throws ErrnoException {
+        throw new ErrnoException();
+    }
+
+    @RequiresApi(27)
+    public static int ioctlInt(FileDescriptor fd, int cmd, Int32Ref arg) throws ErrnoException {
+        throw new ErrnoException();
+    }
+
+    @RequiresApi(31)
+    public static int ioctlInt(FileDescriptor fd, int cmd) throws ErrnoException {
+        throw new ErrnoException();
+    }
+}

hiddenapi-stubs/src/main/java/android/util/MutableInt.java

@@ -0,0 +1,9 @@
+package android.util;
+
+public final class MutableInt {
+    public int value;
+
+    public MutableInt(int value) {
+        this.value = value;
+    }
+}