Initial checkin for bpf project

Copied the files from system/netd into system/bpf. No modification is
made to the files.

Test: this doesn't build since the Android.bp file is missing
Bug: 112334572

Change-Id: Ia090a429dd416e07c46766784fb3dd2037201525
diff --git a/libbpf/BpfMapTest.cpp b/libbpf/BpfMapTest.cpp
new file mode 100644
index 0000000..e367bdb
--- /dev/null
+++ b/libbpf/BpfMapTest.cpp
@@ -0,0 +1,276 @@
+/*
+ * 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 <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include <fcntl.h>
+#include <inttypes.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 <android-base/stringprintf.h>
+#include <android-base/strings.h>
+
+#include <netdutils/MockSyscalls.h>
+#include "bpf/BpfMap.h"
+#include "bpf/BpfNetworkStats.h"
+#include "bpf/BpfUtils.h"
+
+using ::testing::_;
+using ::testing::ByMove;
+using ::testing::Invoke;
+using ::testing::Return;
+using ::testing::StrictMock;
+using ::testing::Test;
+
+namespace android {
+namespace bpf {
+
+using base::unique_fd;
+using netdutils::StatusOr;
+
+constexpr uint32_t TEST_MAP_SIZE = 10;
+constexpr uint32_t TEST_KEY1 = 1;
+constexpr uint32_t TEST_VALUE1 = 10;
+constexpr const char PINNED_MAP_PATH[] = "/sys/fs/bpf/testMap";
+
+class BpfMapTest : public testing::Test {
+  protected:
+    BpfMapTest() {}
+    int mMapFd;
+
+    void SetUp() {
+        if (!access(PINNED_MAP_PATH, R_OK)) {
+            EXPECT_EQ(0, remove(PINNED_MAP_PATH));
+        }
+        mMapFd = createMap(BPF_MAP_TYPE_HASH, sizeof(uint32_t), sizeof(uint32_t), TEST_MAP_SIZE,
+                           BPF_F_NO_PREALLOC);
+    }
+
+    void TearDown() {
+        if (!access(PINNED_MAP_PATH, R_OK)) {
+            EXPECT_EQ(0, remove(PINNED_MAP_PATH));
+        }
+        close(mMapFd);
+    }
+
+    void checkMapInvalid(BpfMap<uint32_t, uint32_t>& map) {
+        EXPECT_FALSE(map.isValid());
+        EXPECT_EQ(-1, map.getMap().get());
+        EXPECT_TRUE(map.getPinnedPath().empty());
+    }
+
+    void checkMapValid(BpfMap<uint32_t, uint32_t>& map) {
+        EXPECT_LE(0, map.getMap().get());
+        EXPECT_TRUE(map.isValid());
+    }
+
+    void writeToMapAndCheck(BpfMap<uint32_t, uint32_t>& map, uint32_t key, uint32_t value) {
+        ASSERT_TRUE(isOk(map.writeValue(key, value, BPF_ANY)));
+        uint32_t value_read;
+        ASSERT_EQ(0, findMapEntry(map.getMap(), &key, &value_read));
+        checkValueAndStatus(value, value_read);
+    }
+
+    void checkValueAndStatus(uint32_t refValue, StatusOr<uint32_t> value) {
+        ASSERT_TRUE(isOk(value.status()));
+        ASSERT_EQ(refValue, value.value());
+    }
+
+    void populateMap(uint32_t total, BpfMap<uint32_t, uint32_t>& map) {
+        for (uint32_t key = 0; key < total; key++) {
+            uint32_t value = key * 10;
+            EXPECT_TRUE(isOk(map.writeValue(key, value, BPF_ANY)));
+        }
+    }
+
+    void expectMapEmpty(BpfMap<uint32_t, uint32_t>& map) {
+        auto isEmpty = map.isEmpty();
+        ASSERT_TRUE(isOk(isEmpty));
+        ASSERT_TRUE(isEmpty.value());
+    }
+};
+
+TEST_F(BpfMapTest, constructor) {
+    BpfMap<uint32_t, uint32_t> testMap1;
+    checkMapInvalid(testMap1);
+
+    BpfMap<uint32_t, uint32_t> testMap2(mMapFd);
+    checkMapValid(testMap2);
+    EXPECT_TRUE(testMap2.getPinnedPath().empty());
+
+    BpfMap<uint32_t, uint32_t> testMap3(BPF_MAP_TYPE_HASH, TEST_MAP_SIZE, BPF_F_NO_PREALLOC);
+    checkMapValid(testMap3);
+    EXPECT_TRUE(testMap3.getPinnedPath().empty());
+}
+
+TEST_F(BpfMapTest, basicHelpers) {
+    BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+    uint32_t key = TEST_KEY1;
+    uint32_t value_write = TEST_VALUE1;
+    writeToMapAndCheck(testMap, key, value_write);
+    StatusOr<uint32_t> value_read = testMap.readValue(key);
+    checkValueAndStatus(value_write, value_read);
+    StatusOr<uint32_t> key_read = testMap.getFirstKey();
+    checkValueAndStatus(key, key_read);
+    ASSERT_TRUE(isOk(testMap.deleteValue(key)));
+    ASSERT_GT(0, findMapEntry(testMap.getMap(), &key, &value_read));
+    ASSERT_EQ(ENOENT, errno);
+}
+
+TEST_F(BpfMapTest, reset) {
+    BpfMap<uint32_t, uint32_t> testMap;
+    testMap.reset(mMapFd);
+    uint32_t key = TEST_KEY1;
+    uint32_t value_write = TEST_VALUE1;
+    writeToMapAndCheck(testMap, key, value_write);
+    testMap.reset();
+    checkMapInvalid(testMap);
+    unique_fd invalidFd(mMapFd);
+    ASSERT_GT(0, findMapEntry(invalidFd, &key, &value_write));
+    ASSERT_EQ(EBADF, errno);
+}
+
+TEST_F(BpfMapTest, moveConstructor) {
+    BpfMap<uint32_t, uint32_t> testMap1(mMapFd);
+    BpfMap<uint32_t, uint32_t> testMap2;
+    testMap2 = std::move(testMap1);
+    uint32_t key = TEST_KEY1;
+    checkMapInvalid(testMap1);
+    uint32_t value = TEST_VALUE1;
+    writeToMapAndCheck(testMap2, key, value);
+}
+
+TEST_F(BpfMapTest, pinnedToPath) {
+    BpfMap<uint32_t, uint32_t> testMap1(mMapFd);
+    EXPECT_OK(testMap1.pinToPath(PINNED_MAP_PATH));
+    EXPECT_EQ(0, access(PINNED_MAP_PATH, R_OK));
+    EXPECT_EQ(0, testMap1.getPinnedPath().compare(PINNED_MAP_PATH));
+    BpfMap<uint32_t, uint32_t> testMap2(mapRetrieve(PINNED_MAP_PATH, 0));
+    checkMapValid(testMap2);
+    uint32_t key = TEST_KEY1;
+    uint32_t value = TEST_VALUE1;
+    writeToMapAndCheck(testMap1, key, value);
+    StatusOr<uint32_t> value_read = testMap2.readValue(key);
+    checkValueAndStatus(value, value_read);
+}
+
+TEST_F(BpfMapTest, SetUpMap) {
+    BpfMap<uint32_t, uint32_t> testMap1;
+    EXPECT_OK(testMap1.getOrCreate(TEST_MAP_SIZE, PINNED_MAP_PATH, BPF_MAP_TYPE_HASH));
+    EXPECT_EQ(0, access(PINNED_MAP_PATH, R_OK));
+    checkMapValid(testMap1);
+    EXPECT_EQ(0, testMap1.getPinnedPath().compare(PINNED_MAP_PATH));
+    BpfMap<uint32_t, uint32_t> testMap2;
+    EXPECT_OK(testMap2.getOrCreate(TEST_MAP_SIZE, PINNED_MAP_PATH, BPF_MAP_TYPE_HASH));
+    checkMapValid(testMap2);
+    EXPECT_EQ(0, testMap2.getPinnedPath().compare(PINNED_MAP_PATH));
+    uint32_t key = TEST_KEY1;
+    uint32_t value = TEST_VALUE1;
+    writeToMapAndCheck(testMap1, key, value);
+    StatusOr<uint32_t> value_read = testMap2.readValue(key);
+    checkValueAndStatus(value, value_read);
+}
+
+TEST_F(BpfMapTest, iterate) {
+    BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+    populateMap(TEST_MAP_SIZE, testMap);
+    int totalCount = 0;
+    int totalSum = 0;
+    const auto iterateWithDeletion = [&totalCount, &totalSum](const uint32_t& key,
+                                                              BpfMap<uint32_t, uint32_t>& map) {
+        EXPECT_GE((uint32_t)TEST_MAP_SIZE, key);
+        totalCount++;
+        totalSum += key;
+        return map.deleteValue(key);
+    };
+    EXPECT_OK(testMap.iterate(iterateWithDeletion));
+    EXPECT_EQ((int)TEST_MAP_SIZE, totalCount);
+    EXPECT_EQ(((1 + TEST_MAP_SIZE - 1) * (TEST_MAP_SIZE - 1)) / 2, (uint32_t)totalSum);
+    expectMapEmpty(testMap);
+}
+
+TEST_F(BpfMapTest, iterateWithValue) {
+    BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+    populateMap(TEST_MAP_SIZE, testMap);
+    int totalCount = 0;
+    int totalSum = 0;
+    const auto iterateWithDeletion = [&totalCount, &totalSum](const uint32_t& key,
+                                                              const uint32_t& value,
+                                                              BpfMap<uint32_t, uint32_t>& map) {
+        EXPECT_GE((uint32_t)TEST_MAP_SIZE, key);
+        EXPECT_EQ(value, key * 10);
+        totalCount++;
+        totalSum += value;
+        return map.deleteValue(key);
+    };
+    EXPECT_OK(testMap.iterateWithValue(iterateWithDeletion));
+    EXPECT_EQ((int)TEST_MAP_SIZE, totalCount);
+    EXPECT_EQ(((1 + TEST_MAP_SIZE - 1) * (TEST_MAP_SIZE - 1)) * 5, (uint32_t)totalSum);
+    expectMapEmpty(testMap);
+}
+
+TEST_F(BpfMapTest, mapIsEmpty) {
+    BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+    expectMapEmpty(testMap);
+    uint32_t key = TEST_KEY1;
+    uint32_t value_write = TEST_VALUE1;
+    writeToMapAndCheck(testMap, key, value_write);
+    auto isEmpty = testMap.isEmpty();
+    ASSERT_TRUE(isOk(isEmpty));
+    ASSERT_FALSE(isEmpty.value());
+    ASSERT_TRUE(isOk(testMap.deleteValue(key)));
+    ASSERT_GT(0, findMapEntry(testMap.getMap(), &key, &value_write));
+    ASSERT_EQ(ENOENT, errno);
+    expectMapEmpty(testMap);
+    int entriesSeen = 0;
+    EXPECT_OK(testMap.iterate(
+            [&entriesSeen](const unsigned int&,
+                           const BpfMap<unsigned int, unsigned int>&) -> netdutils::Status {
+                entriesSeen++;
+                return netdutils::status::ok;
+            }));
+    EXPECT_EQ(0, entriesSeen);
+    EXPECT_OK(testMap.iterateWithValue(
+            [&entriesSeen](const unsigned int&, const unsigned int&,
+                           const BpfMap<unsigned int, unsigned int>&) -> netdutils::Status {
+                entriesSeen++;
+                return netdutils::status::ok;
+            }));
+    EXPECT_EQ(0, entriesSeen);
+}
+
+TEST_F(BpfMapTest, mapClear) {
+    BpfMap<uint32_t, uint32_t> testMap(mMapFd);
+    populateMap(TEST_MAP_SIZE, testMap);
+    auto isEmpty = testMap.isEmpty();
+    ASSERT_TRUE(isOk(isEmpty));
+    ASSERT_FALSE(isEmpty.value());
+    ASSERT_TRUE(isOk(testMap.clear()));
+    expectMapEmpty(testMap);
+}
+
+}  // namespace bpf
+}  // namespace android