simplify netd updatable

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I8987f33b3f3427683e5ae9b2931528f91d6f0aeb
diff --git a/netd/BpfHandler.cpp b/netd/BpfHandler.cpp
index 2810d80..994db1d 100644
--- a/netd/BpfHandler.cpp
+++ b/netd/BpfHandler.cpp
@@ -134,18 +134,16 @@
 
 int BpfHandler::tagSocket(int sockFd, uint32_t tag, uid_t chargeUid, uid_t realUid) {
     std::lock_guard guard(mMutex);
-    if (chargeUid != realUid && !hasUpdateDeviceStatsPermission(realUid)) {
-        return -EPERM;
-    }
+    if (!mCookieTagMap.isValid()) return -EPERM;
+
+    if (chargeUid != realUid && !hasUpdateDeviceStatsPermission(realUid)) return -EPERM;
 
     // Note that tagging the socket to AID_CLAT is only implemented in JNI ClatCoordinator.
     // The process is not allowed to tag socket to AID_CLAT via tagSocket() which would cause
     // process data usage accounting to be bypassed. Tagging AID_CLAT is used for avoiding counting
     // CLAT traffic data usage twice. See packages/modules/Connectivity/service/jni/
     // com_android_server_connectivity_ClatCoordinator.cpp
-    if (chargeUid == AID_CLAT) {
-        return -EPERM;
-    }
+    if (chargeUid == AID_CLAT) return -EPERM;
 
     // The socket destroy listener only monitors on the group {INET_TCP, INET_UDP, INET6_TCP,
     // INET6_UDP}. Tagging listener unsupported socket causes that the tag can't be removed from
@@ -180,6 +178,7 @@
 
     uint64_t sock_cookie = getSocketCookie(sockFd);
     if (sock_cookie == NONEXISTENT_COOKIE) return -errno;
+
     UidTagValue newKey = {.uid = (uint32_t)chargeUid, .tag = tag};
 
     uint32_t totalEntryCount = 0;
@@ -242,9 +241,11 @@
 
 int BpfHandler::untagSocket(int sockFd) {
     std::lock_guard guard(mMutex);
-    uint64_t sock_cookie = getSocketCookie(sockFd);
 
+    uint64_t sock_cookie = getSocketCookie(sockFd);
     if (sock_cookie == NONEXISTENT_COOKIE) return -errno;
+
+    if (!mCookieTagMap.isValid()) return -EPERM;
     base::Result<void> res = mCookieTagMap.deleteValue(sock_cookie);
     if (!res.ok()) {
         ALOGE("Failed to untag socket: %s", strerror(res.error().code()));
diff --git a/netd/NetdUpdatable.cpp b/netd/NetdUpdatable.cpp
index f0997fc..41b1fdb 100644
--- a/netd/NetdUpdatable.cpp
+++ b/netd/NetdUpdatable.cpp
@@ -16,19 +16,20 @@
 
 #define LOG_TAG "NetdUpdatable"
 
-#include "NetdUpdatable.h"
+#include "BpfHandler.h"
 
 #include <android-base/logging.h>
 #include <netdutils/Status.h>
 
 #include "NetdUpdatablePublic.h"
 
+static android::net::BpfHandler sBpfHandler;
+
 int libnetd_updatable_init(const char* cg2_path) {
     android::base::InitLogging(/*argv=*/nullptr);
     LOG(INFO) << __func__ << ": Initializing";
 
-    android::net::gNetdUpdatable = android::net::NetdUpdatable::getInstance();
-    android::netdutils::Status ret = android::net::gNetdUpdatable->mBpfHandler.init(cg2_path);
+    android::netdutils::Status ret = sBpfHandler.init(cg2_path);
     if (!android::netdutils::isOk(ret)) {
         LOG(ERROR) << __func__ << ": BPF handler init failed";
         return -ret.code();
@@ -37,25 +38,9 @@
 }
 
 int libnetd_updatable_tagSocket(int sockFd, uint32_t tag, uid_t chargeUid, uid_t realUid) {
-    if (android::net::gNetdUpdatable == nullptr) return -EPERM;
-    return android::net::gNetdUpdatable->mBpfHandler.tagSocket(sockFd, tag, chargeUid, realUid);
+    return sBpfHandler.tagSocket(sockFd, tag, chargeUid, realUid);
 }
 
 int libnetd_updatable_untagSocket(int sockFd) {
-    if (android::net::gNetdUpdatable == nullptr) return -EPERM;
-    return android::net::gNetdUpdatable->mBpfHandler.untagSocket(sockFd);
+    return sBpfHandler.untagSocket(sockFd);
 }
-
-namespace android {
-namespace net {
-
-NetdUpdatable* gNetdUpdatable = nullptr;
-
-NetdUpdatable* NetdUpdatable::getInstance() {
-    // Instantiated on first use.
-    static NetdUpdatable instance;
-    return &instance;
-}
-
-}  // namespace net
-}  // namespace android
diff --git a/netd/NetdUpdatable.h b/netd/NetdUpdatable.h
deleted file mode 100644
index 333037f..0000000
--- a/netd/NetdUpdatable.h
+++ /dev/null
@@ -1,37 +0,0 @@
-/**
- * Copyright (c) 2022, 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 "BpfHandler.h"
-
-namespace android {
-namespace net {
-
-class NetdUpdatable {
-  public:
-    NetdUpdatable() = default;
-    NetdUpdatable(const NetdUpdatable&) = delete;
-    NetdUpdatable& operator=(const NetdUpdatable&) = delete;
-    static NetdUpdatable* getInstance();
-
-    BpfHandler mBpfHandler;
-};
-
-extern NetdUpdatable* gNetdUpdatable;
-
-}  // namespace net
-}  // namespace android
\ No newline at end of file