wire bpf_base_test into netd_updatable_unit_test

The 3 pre-existing //system/netd tests are:
  TEST_F(BpfBasicTest, TestCgroupMounted)
  TEST_F(BpfBasicTest, TestTagSocket)
  TEST_F(BpfBasicTest, TestCloseSocketWithoutUntag)
which are directly related to BpfHandler.cpp implementation,
as it implements:
  Status BpfHandler::init(const char* cg2_path)
  BpfHandler::tagSocket()
  BpfHandler::untagSocket()

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I1c01ae90904faaea54b427495c7a5deab8b1b900

netd/BpfBaseTest.cpp

@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+#include <string>
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <linux/inet_diag.h>
+#include <linux/sock_diag.h>
+#include <net/if.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <gtest/gtest.h>
+
+#include <cutils/qtaguid.h>
+#include <processgroup/processgroup.h>
+
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+#include <netdutils/NetNativeTestBase.h>
+
+#include "bpf/BpfMap.h"
+#include "bpf/BpfUtils.h"
+#include "netd.h"
+
+using android::base::Result;
+
+namespace android {
+namespace bpf {
+
+// Use the upper limit of uid to avoid conflict with real app uids. We can't use UID_MAX because
+// it's -1, which is INVALID_UID.
+constexpr uid_t TEST_UID = UID_MAX - 1;
+constexpr uint32_t TEST_TAG = 42;
+
+class BpfBasicTest : public NetNativeTestBase {
+  protected:
+    BpfBasicTest() {}
+};
+
+TEST_F(BpfBasicTest, TestCgroupMounted) {
+    std::string cg2_path;
+    ASSERT_EQ(true, CgroupGetControllerPath(CGROUPV2_CONTROLLER_NAME, &cg2_path));
+    ASSERT_EQ(0, access(cg2_path.c_str(), R_OK));
+    ASSERT_EQ(0, access((cg2_path + "/cgroup.controllers").c_str(), R_OK));
+}
+
+TEST_F(BpfBasicTest, TestTagSocket) {
+    BpfMap<uint64_t, UidTagValue> cookieTagMap(COOKIE_TAG_MAP_PATH);
+    ASSERT_TRUE(cookieTagMap.isValid());
+    int sock = socket(AF_INET6, SOCK_STREAM | SOCK_CLOEXEC, 0);
+    ASSERT_LE(0, sock);
+    uint64_t cookie = getSocketCookie(sock);
+    ASSERT_NE(NONEXISTENT_COOKIE, cookie);
+    ASSERT_EQ(0, qtaguid_tagSocket(sock, TEST_TAG, TEST_UID));
+    Result<UidTagValue> tagResult = cookieTagMap.readValue(cookie);
+    ASSERT_RESULT_OK(tagResult);
+    ASSERT_EQ(TEST_UID, tagResult.value().uid);
+    ASSERT_EQ(TEST_TAG, tagResult.value().tag);
+    ASSERT_EQ(0, qtaguid_untagSocket(sock));
+    tagResult = cookieTagMap.readValue(cookie);
+    ASSERT_FALSE(tagResult.ok());
+    ASSERT_EQ(ENOENT, tagResult.error().code());
+}
+
+TEST_F(BpfBasicTest, TestCloseSocketWithoutUntag) {
+    BpfMap<uint64_t, UidTagValue> cookieTagMap(COOKIE_TAG_MAP_PATH);
+    ASSERT_TRUE(cookieTagMap.isValid());
+    int sock = socket(AF_INET6, SOCK_STREAM | SOCK_CLOEXEC, 0);
+    ASSERT_LE(0, sock);
+    uint64_t cookie = getSocketCookie(sock);
+    ASSERT_NE(NONEXISTENT_COOKIE, cookie);
+    ASSERT_EQ(0, qtaguid_tagSocket(sock, TEST_TAG, TEST_UID));
+    Result<UidTagValue> tagResult = cookieTagMap.readValue(cookie);
+    ASSERT_RESULT_OK(tagResult);
+    ASSERT_EQ(TEST_UID, tagResult.value().uid);
+    ASSERT_EQ(TEST_TAG, tagResult.value().tag);
+    ASSERT_EQ(0, close(sock));
+    // Check map periodically until sk destroy handler have done its job.
+    for (int i = 0; i < 10; i++) {
+        usleep(5000);  // 5ms
+        tagResult = cookieTagMap.readValue(cookie);
+        if (!tagResult.ok()) {
+            ASSERT_EQ(ENOENT, tagResult.error().code());
+            return;
+        }
+    }
+    FAIL() << "socket tag still exist after 50ms";
+}
+
+}
+}