diff --git a/staticlibs/device/android/net/NetworkFactory.java b/staticlibs/device/android/net/NetworkFactory.java
index 4bc45cf..bcc6089 100644
--- a/staticlibs/device/android/net/NetworkFactory.java
+++ b/staticlibs/device/android/net/NetworkFactory.java
@@ -247,7 +247,7 @@
     /** @deprecated None of the implementors use the score, remove this method */
     @Deprecated
     public boolean acceptRequest(NetworkRequest request, int score) {
-        return true;
+        return acceptRequest(request);
     }
 
     /**
diff --git a/staticlibs/framework/com/android/net/module/util/PermissionUtils.java b/staticlibs/framework/com/android/net/module/util/PermissionUtils.java
new file mode 100644
index 0000000..ce8a745
--- /dev/null
+++ b/staticlibs/framework/com/android/net/module/util/PermissionUtils.java
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2021 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.android.net.module.util;
+
+import static android.content.pm.PackageManager.PERMISSION_GRANTED;
+
+import android.annotation.NonNull;
+import android.content.Context;
+
+/**
+ * Collection of permission utilities.
+ * @hide
+ */
+public final class PermissionUtils {
+    /**
+     * Return true if the context has one of given permission.
+     */
+    public static boolean checkAnyPermissionOf(@NonNull Context context,
+            @NonNull String... permissions) {
+        for (String permission : permissions) {
+            if (context.checkCallingOrSelfPermission(permission) == PERMISSION_GRANTED) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Enforce permission check on the context that should have one of given permission.
+     */
+    public static void enforceAnyPermissionOf(@NonNull Context context,
+            @NonNull String... permissions) {
+        if (!checkAnyPermissionOf(context, permissions)) {
+            throw new SecurityException("Requires one of the following permissions: "
+                    + String.join(", ", permissions) + ".");
+        }
+    }
+}
diff --git a/staticlibs/native/bpf_syscall_wrappers/Android.bp b/staticlibs/native/bpf_syscall_wrappers/Android.bp
new file mode 100644
index 0000000..ae6eee0
--- /dev/null
+++ b/staticlibs/native/bpf_syscall_wrappers/Android.bp
@@ -0,0 +1,35 @@
+// Copyright (C) 2021 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.
+
+cc_library_headers {
+    name: "bpf_syscall_wrappers",
+    vendor_available: false,
+    host_supported: false,
+    native_bridge_supported: true,
+    export_include_dirs: ["include"],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    sdk_version: "30",
+    min_sdk_version: "30",
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.tethering",
+    ],
+    visibility: [
+        "//packages/modules/Connectivity/Tethering",
+        "//system/bpf/libbpf_android",
+    ],
+}
diff --git a/staticlibs/native/bpf_syscall_wrappers/include/BpfSyscallWrappers.h b/staticlibs/native/bpf_syscall_wrappers/include/BpfSyscallWrappers.h
new file mode 100644
index 0000000..72eebf3
--- /dev/null
+++ b/staticlibs/native/bpf_syscall_wrappers/include/BpfSyscallWrappers.h
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#pragma once
+
+#include <linux/bpf.h>
+#include <linux/unistd.h>
+
+#ifdef BPF_FD_JUST_USE_INT
+  #define BPF_FD_TYPE int
+  #define BPF_FD_TO_U32(x) static_cast<__u32>(x)
+#else
+  #include <android-base/unique_fd.h>
+  #define BPF_FD_TYPE base::unique_fd&
+  #define BPF_FD_TO_U32(x) static_cast<__u32>((x).get())
+#endif
+
+#define ptr_to_u64(x) ((uint64_t)(uintptr_t)(x))
+
+namespace android {
+namespace bpf {
+
+/* Note: bpf_attr is a union which might have a much larger size then the anonymous struct portion
+ * of it that we are using.  The kernel's bpf() system call will perform a strict check to ensure
+ * all unused portions are zero.  It will fail with E2BIG if we don't fully zero bpf_attr.
+ */
+
+inline int bpf(int cmd, const bpf_attr& attr) {
+    return syscall(__NR_bpf, cmd, &attr, sizeof(attr));
+}
+
+inline int createMap(bpf_map_type map_type, uint32_t key_size, uint32_t value_size,
+                     uint32_t max_entries, uint32_t map_flags) {
+    return bpf(BPF_MAP_CREATE, {
+                                       .map_type = map_type,
+                                       .key_size = key_size,
+                                       .value_size = value_size,
+                                       .max_entries = max_entries,
+                                       .map_flags = map_flags,
+                               });
+}
+
+inline int writeToMapEntry(const BPF_FD_TYPE map_fd, const void* key, const void* value,
+                           uint64_t flags) {
+    return bpf(BPF_MAP_UPDATE_ELEM, {
+                                            .map_fd = BPF_FD_TO_U32(map_fd),
+                                            .key = ptr_to_u64(key),
+                                            .value = ptr_to_u64(value),
+                                            .flags = flags,
+                                    });
+}
+
+inline int findMapEntry(const BPF_FD_TYPE map_fd, const void* key, void* value) {
+    return bpf(BPF_MAP_LOOKUP_ELEM, {
+                                            .map_fd = BPF_FD_TO_U32(map_fd),
+                                            .key = ptr_to_u64(key),
+                                            .value = ptr_to_u64(value),
+                                    });
+}
+
+inline int deleteMapEntry(const BPF_FD_TYPE map_fd, const void* key) {
+    return bpf(BPF_MAP_DELETE_ELEM, {
+                                            .map_fd = BPF_FD_TO_U32(map_fd),
+                                            .key = ptr_to_u64(key),
+                                    });
+}
+
+inline int getNextMapKey(const BPF_FD_TYPE map_fd, const void* key, void* next_key) {
+    return bpf(BPF_MAP_GET_NEXT_KEY, {
+                                             .map_fd = BPF_FD_TO_U32(map_fd),
+                                             .key = ptr_to_u64(key),
+                                             .next_key = ptr_to_u64(next_key),
+                                     });
+}
+
+inline int getFirstMapKey(const BPF_FD_TYPE map_fd, void* firstKey) {
+    return getNextMapKey(map_fd, NULL, firstKey);
+}
+
+inline int bpfFdPin(const BPF_FD_TYPE map_fd, const char* pathname) {
+    return bpf(BPF_OBJ_PIN, {
+                                    .pathname = ptr_to_u64(pathname),
+                                    .bpf_fd = BPF_FD_TO_U32(map_fd),
+                            });
+}
+
+inline int bpfFdGet(const char* pathname, uint32_t flag) {
+    return bpf(BPF_OBJ_GET, {
+                                    .pathname = ptr_to_u64(pathname),
+                                    .file_flags = flag,
+                            });
+}
+
+inline int mapRetrieve(const char* pathname, uint32_t flag) {
+    return bpfFdGet(pathname, flag);
+}
+
+inline int mapRetrieveRW(const char* pathname) {
+    return mapRetrieve(pathname, 0);
+}
+
+inline int mapRetrieveRO(const char* pathname) {
+    return mapRetrieve(pathname, BPF_F_RDONLY);
+}
+
+inline int mapRetrieveWO(const char* pathname) {
+    return mapRetrieve(pathname, BPF_F_WRONLY);
+}
+
+inline int retrieveProgram(const char* pathname) {
+    return bpfFdGet(pathname, BPF_F_RDONLY);
+}
+
+inline int attachProgram(bpf_attach_type type, const BPF_FD_TYPE prog_fd,
+                         const BPF_FD_TYPE cg_fd) {
+    return bpf(BPF_PROG_ATTACH, {
+                                        .target_fd = BPF_FD_TO_U32(cg_fd),
+                                        .attach_bpf_fd = BPF_FD_TO_U32(prog_fd),
+                                        .attach_type = type,
+                                });
+}
+
+inline int detachProgram(bpf_attach_type type, const BPF_FD_TYPE cg_fd) {
+    return bpf(BPF_PROG_DETACH, {
+                                        .target_fd = BPF_FD_TO_U32(cg_fd),
+                                        .attach_type = type,
+                                });
+}
+
+}  // namespace bpf
+}  // namespace android
+
+#undef ptr_to_u64
+#undef BPF_FD_TO_U32
+#undef BPF_FD_TYPE
+#undef BPF_FD_JUST_USE_INT