// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40284755): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif
#include "net/dns/dns_config_service_posix.h"
#include <resolv.h>
#include <memory>
#include <optional>
#include "base/cancelable_callback.h"
#include "base/files/file_util.h"
#include "base/functional/bind.h"
#include "base/run_loop.h"
#include "base/sys_byteorder.h"
#include "base/task/sequenced_task_runner.h"
#include "base/task/task_traits.h"
#include "base/task/thread_pool.h"
#include "base/test/task_environment.h"
#include "base/test/test_timeouts.h"
#include "build/build_config.h"
#include "net/base/ip_address.h"
#include "net/dns/dns_config.h"
#include "net/dns/public/dns_protocol.h"
#include "testing/gtest/include/gtest/gtest.h"
#if BUILDFLAG(IS_ANDROID)
#include "base/android/path_utils.h"
#endif // BUILDFLAG(IS_ANDROID)
// Required for inet_pton()
#if BUILDFLAG(IS_WIN)
#include <winsock2.h>
#else
#include <arpa/inet.h>
#endif
namespace net {
namespace {
// MAXNS is normally 3, but let's test 4 if possible.
const char* const kNameserversIPv4[] = {
"8.8.8.8",
"192.168.1.1",
"63.1.2.4",
"1.0.0.1",
};
#if BUILDFLAG(IS_CHROMEOS)
const char* const kNameserversIPv6[] = {
nullptr,
"2001:DB8:0::42",
nullptr,
"::FFFF:129.144.52.38",
};
#endif
void DummyConfigCallback(const DnsConfig& config) {
// Do nothing
}
// Fills in |res| with sane configuration.
void InitializeResState(res_state res) {
memset(res, 0, sizeof(*res));
res->options = RES_INIT | RES_RECURSE | RES_DEFNAMES | RES_DNSRCH |
RES_ROTATE;
res->ndots = 2;
res->retrans = 4;
res->retry = 7;
const char kDnsrch[] = "chromium.org" "\0" "example.com";
memcpy(res->defdname, kDnsrch, sizeof(kDnsrch));
res->dnsrch[0] = res->defdname;
res->dnsrch[1] = res->defdname + sizeof("chromium.org");
for (unsigned i = 0; i < std::size(kNameserversIPv4) && i < MAXNS; ++i) {
struct sockaddr_in sa;
sa.sin_family = AF_INET;
sa.sin_port = base::HostToNet16(NS_DEFAULTPORT + i);
inet_pton(AF_INET, kNameserversIPv4[i], &sa.sin_addr);
res->nsaddr_list[i] = sa;
++res->nscount;
}
#if BUILDFLAG(IS_CHROMEOS)
// Install IPv6 addresses, replacing the corresponding IPv4 addresses.
unsigned nscount6 = 0;
for (unsigned i = 0; i < std::size(kNameserversIPv6) && i < MAXNS; ++i) {
if (!kNameserversIPv6[i])
continue;
// Must use malloc to mimick res_ninit.
struct sockaddr_in6 *sa6;
sa6 = (struct sockaddr_in6 *)malloc(sizeof(*sa6));
sa6->sin6_family = AF_INET6;
sa6->sin6_port = base::HostToNet16(NS_DEFAULTPORT - i);
inet_pton(AF_INET6, kNameserversIPv6[i], &sa6->sin6_addr);
res->_u._ext.nsaddrs[i] = sa6;
memset(&res->nsaddr_list[i], 0, sizeof res->nsaddr_list[i]);
++nscount6;
}
res->_u._ext.nscount6 = nscount6;
#endif
}
void CloseResState(res_state res) {
#if BUILDFLAG(IS_CHROMEOS)
for (int i = 0; i < res->nscount; ++i) {
if (res->_u._ext.nsaddrs[i] != nullptr)
free(res->_u._ext.nsaddrs[i]);
}
#endif
}
void InitializeExpectedConfig(DnsConfig* config) {
config->ndots = 2;
config->fallback_period = base::Seconds(4);
config->attempts = 7;
config->rotate = true;
config->append_to_multi_label_name = true;
config->search.clear();
config->search.push_back("chromium.org");
config->search.push_back("example.com");
config->nameservers.clear();
for (unsigned i = 0; i < std::size(kNameserversIPv4) && i < MAXNS; ++i) {
IPAddress ip;
EXPECT_TRUE(ip.AssignFromIPLiteral(kNameserversIPv4[i]));
config->nameservers.push_back(IPEndPoint(ip, NS_DEFAULTPORT + i));
}
#if BUILDFLAG(IS_CHROMEOS)
for (unsigned i = 0; i < std::size(kNameserversIPv6) && i < MAXNS; ++i) {
if (!kNameserversIPv6[i])
continue;
IPAddress ip;
EXPECT_TRUE(ip.AssignFromIPLiteral(kNameserversIPv6[i]));
config->nameservers[i] = IPEndPoint(ip, NS_DEFAULTPORT - i);
}
#endif
}
TEST(DnsConfigServicePosixTest, CreateAndDestroy) {
// Regression test to verify crash does not occur if DnsConfigServicePosix
// instance is destroyed without calling WatchConfig()
base::test::TaskEnvironment task_environment(
base::test::TaskEnvironment::MainThreadType::IO);
auto service = std::make_unique<internal::DnsConfigServicePosix>();
service.reset();
task_environment.RunUntilIdle();
}
TEST(DnsConfigServicePosixTest, ConvertResStateToDnsConfig) {
struct __res_state res;
InitializeResState(&res);
std::optional<DnsConfig> config = internal::ConvertResStateToDnsConfig(res);
CloseResState(&res);
ASSERT_TRUE(config.has_value());
EXPECT_TRUE(config->IsValid());
DnsConfig expected_config;
EXPECT_FALSE(expected_config.EqualsIgnoreHosts(config.value()));
InitializeExpectedConfig(&expected_config);
EXPECT_TRUE(expected_config.EqualsIgnoreHosts(config.value()));
}
TEST(DnsConfigServicePosixTest, RejectEmptyNameserver) {
struct __res_state res = {};
res.options = RES_INIT | RES_RECURSE | RES_DEFNAMES | RES_DNSRCH;
const char kDnsrch[] = "chromium.org";
memcpy(res.defdname, kDnsrch, sizeof(kDnsrch));
res.dnsrch[0] = res.defdname;
struct sockaddr_in sa = {};
sa.sin_family = AF_INET;
sa.sin_port = base::HostToNet16(NS_DEFAULTPORT);
sa.sin_addr.s_addr = INADDR_ANY;
res.nsaddr_list[0] = sa;
sa.sin_addr.s_addr = 0xCAFE1337;
res.nsaddr_list[1] = sa;
res.nscount = 2;
EXPECT_FALSE(internal::ConvertResStateToDnsConfig(res));
sa.sin_addr.s_addr = 0xDEADBEEF;
res.nsaddr_list[0] = sa;
EXPECT_TRUE(internal::ConvertResStateToDnsConfig(res));
}
TEST(DnsConfigServicePosixTest, DestroyWhileJobsWorking) {
// Regression test to verify crash does not occur if DnsConfigServicePosix
// instance is destroyed while SerialWorker jobs have posted to worker pool.
base::test::TaskEnvironment task_environment(
base::test::TaskEnvironment::MainThreadType::IO,
base::test::TaskEnvironment::TimeSource::MOCK_TIME);
auto service = std::make_unique<internal::DnsConfigServicePosix>();
// Call WatchConfig() which also tests ReadConfig().
service->WatchConfig(base::BindRepeating(&DummyConfigCallback));
service.reset();
task_environment.FastForwardUntilNoTasksRemain();
}
TEST(DnsConfigServicePosixTest, DestroyOnDifferentThread) {
// Regression test to verify crash does not occur if DnsConfigServicePosix
// instance is destroyed on another thread.
base::test::TaskEnvironment task_environment;
scoped_refptr<base::SequencedTaskRunner> runner =
base::ThreadPool::CreateSequencedTaskRunner({base::MayBlock()});
std::unique_ptr<internal::DnsConfigServicePosix, base::OnTaskRunnerDeleter>
service(new internal::DnsConfigServicePosix(),
base::OnTaskRunnerDeleter(runner));
runner->PostTask(FROM_HERE,
base::BindOnce(&internal::DnsConfigServicePosix::WatchConfig,
base::Unretained(service.get()),
base::BindRepeating(&DummyConfigCallback)));
service.reset();
task_environment.RunUntilIdle();
}
} // namespace
} // namespace net
Codebase Browser
chromium