1 /*
2 * Copyright (C) 2019 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <regex>
18 #include <thread>
19
20 #include <android-base/strings.h>
21 #include <android-base/test_utils.h>
22 #include <gtest/gtest.h>
23
24 #include "DnsQueryLog.h"
25
26 using namespace std::chrono_literals;
27
28 namespace android::net {
29
30 namespace {
31
32 // Dump the log to STDOUT and capture it.
captureDumpOutput(const DnsQueryLog & queryLog)33 std::string captureDumpOutput(const DnsQueryLog& queryLog) {
34 netdutils::DumpWriter dw(STDOUT_FILENO);
35 CapturedStdout captured;
36 queryLog.dump(dw);
37 return captured.str();
38 }
39
40 // A simple check for the dump result by checking the netIds one by one.
verifyDumpOutput(const std::string & dumpLog,const std::vector<int> & expectedNetIds)41 void verifyDumpOutput(const std::string& dumpLog, const std::vector<int>& expectedNetIds) {
42 // Capture three matches: netId, hostname, and answer (empty allowed).
43 static const std::regex pattern(
44 R"(netId=(\d+).* hostname=([\w\*]+) answer=\[([\w:,\.\*\s]*)\])");
45
46 std::string str(dumpLog);
47 std::smatch sm;
48 for (const auto& netId : expectedNetIds) {
49 SCOPED_TRACE(netId);
50 EXPECT_TRUE(std::regex_search(str, sm, pattern));
51 EXPECT_EQ(sm[1], std::to_string(netId));
52 str = sm.suffix();
53 }
54
55 // Ensure the dumpLog is exactly as expected.
56 EXPECT_FALSE(std::regex_search(str, sm, pattern));
57 }
58
59 } // namespace
60
61 class DnsQueryLogTest : public ::testing::Test {
62 protected:
63 const std::vector<std::string> serversV4 = {"127.0.0.1", "1.2.3.4"};
64 const std::vector<std::string> serversV4V6 = {"127.0.0.1", "1.2.3.4", "2001:db8::1",
65 "fe80:1::2%testnet"};
66 };
67
TEST_F(DnsQueryLogTest,Push)68 TEST_F(DnsQueryLogTest, Push) {
69 std::vector<DnsQueryLog::Record> records = {
70 DnsQueryLog::Record(30, 1000, 1000, "example.com", serversV4, 10),
71 DnsQueryLog::Record(31, 1000, 1000, "", serversV4, 10), // Empty hostname.
72 DnsQueryLog::Record(32, 1000, 1000, "example.com", {}, 10), // No answer.
73 DnsQueryLog::Record(33, 1000, 1000, "example.com", serversV4V6, 10),
74 };
75 DnsQueryLog queryLog;
76 for (auto& r : records) {
77 queryLog.push(std::move(r));
78 }
79
80 std::string output = captureDumpOutput(queryLog);
81 verifyDumpOutput(output, {30, 31, 32, 33});
82 }
83
TEST_F(DnsQueryLogTest,PushStressTest)84 TEST_F(DnsQueryLogTest, PushStressTest) {
85 const int threadNum = 100;
86 const int pushNum = 1000;
87 const size_t size = 500;
88 DnsQueryLog queryLog(size);
89 std::vector<std::thread> threads(threadNum);
90
91 // Launch 'threadNum' threads to push the same queryLog 'pushNum' times.
92 for (auto& thread : threads) {
93 thread = std::thread([&]() {
94 for (int i = 0; i < pushNum; i++) {
95 DnsQueryLog::Record record(30, 1000, 1000, "www.example.com", serversV4, 10);
96 queryLog.push(std::move(record));
97 }
98 });
99 }
100 for (auto& thread : threads) {
101 thread.join();
102 }
103
104 // Verify there are exact 'size' records in queryLog.
105 std::string output = captureDumpOutput(queryLog);
106 verifyDumpOutput(output, std::vector(size, 30));
107 }
108
TEST_F(DnsQueryLogTest,ZeroSize)109 TEST_F(DnsQueryLogTest, ZeroSize) {
110 const size_t size = 0;
111 DnsQueryLog::Record r1(30, 1000, 1000, "www.example1.com", serversV4V6, 10);
112 DnsQueryLog::Record r2(31, 1000, 1000, "www.example2.com", serversV4V6, 10);
113 DnsQueryLog::Record r3(32, 1000, 1000, "www.example3.com", serversV4V6, 10);
114
115 DnsQueryLog queryLog(size);
116 queryLog.push(std::move(r1));
117 queryLog.push(std::move(r2));
118 queryLog.push(std::move(r3));
119
120 std::string output = captureDumpOutput(queryLog);
121 verifyDumpOutput(output, {});
122 }
123
TEST_F(DnsQueryLogTest,CapacityFull)124 TEST_F(DnsQueryLogTest, CapacityFull) {
125 const size_t size = 3;
126 DnsQueryLog::Record r1(30, 1000, 1000, "www.example1.com", serversV4V6, 10);
127 DnsQueryLog::Record r2(31, 1000, 1000, "www.example2.com", serversV4V6, 10);
128 DnsQueryLog::Record r3(32, 1000, 1000, "www.example3.com", serversV4V6, 10);
129 DnsQueryLog::Record r4(33, 1000, 1000, "www.example4.com", serversV4V6, 10);
130 const std::vector<int> expectedNetIds = {31, 32, 33};
131
132 DnsQueryLog queryLog(size);
133 queryLog.push(std::move(r1));
134 queryLog.push(std::move(r2));
135 queryLog.push(std::move(r3));
136 queryLog.push(std::move(r4));
137
138 std::string output = captureDumpOutput(queryLog);
139 verifyDumpOutput(output, expectedNetIds);
140 }
141
TEST_F(DnsQueryLogTest,ValidityTime)142 TEST_F(DnsQueryLogTest, ValidityTime) {
143 DnsQueryLog::Record r1(30, 1000, 1000, "www.example.com", serversV4, 10);
144 DnsQueryLog queryLog(3, 100ms);
145 queryLog.push(std::move(r1));
146
147 // Dump the output and verify the correctness by checking netId.
148 std::string output = captureDumpOutput(queryLog);
149 verifyDumpOutput(output, {30});
150
151 std::this_thread::sleep_for(150ms);
152
153 // The record is expired thus not shown in the output.
154 output = captureDumpOutput(queryLog);
155 verifyDumpOutput(output, {});
156
157 // Push another record to ensure it still works.
158 DnsQueryLog::Record r2(31, 1000, 1000, "example.com", serversV4V6, 10);
159 queryLog.push(std::move(r2));
160 output = captureDumpOutput(queryLog);
161 verifyDumpOutput(output, {31});
162 }
163
164 } // namespace android::net
165