/*
* Copyright (C) 2019 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 <netdb.h>
#include <array>
#include <atomic>
#include <chrono>
#include <ctime>
#include <thread>
#include <android-base/logging.h>
#include <android-base/stringprintf.h>
#include <android/multinetwork.h>
#include <arpa/inet.h>
#include <cutils/properties.h>
#include <gmock/gmock-matchers.h>
#include <gtest/gtest.h>
#include "resolv_cache.h"
#include "resolv_private.h"
#include "stats.h"
#include "tests/dns_responder/dns_responder.h"
#include "tests/resolv_test_utils.h"
using namespace std::chrono_literals;
using android::netdutils::IPSockAddr;
constexpr int TEST_NETID_2 = 31;
constexpr int DNS_PORT = 53;
// Constant values sync'd from res_cache.cpp
constexpr int DNS_HEADER_SIZE = 12;
constexpr int MAX_ENTRIES = 64 * 2 * 5;
namespace {
struct CacheEntry {
std::vector<char> query;
std::vector<char> answer;
};
struct SetupParams {
std::vector<std::string> servers;
std::vector<std::string> domains;
res_params params;
aidl::android::net::ResolverOptionsParcel resolverOptions;
std::vector<int32_t> transportTypes;
};
struct CacheStats {
SetupParams setup;
std::vector<res_stats> stats;
int pendingReqTimeoutCount;
};
std::vector<char> makeQuery(int op, const char* qname, int qclass, int qtype) {
uint8_t buf[MAXPACKET] = {};
const int len = res_nmkquery(op, qname, qclass, qtype, /*data=*/nullptr, /*datalen=*/0, buf,
sizeof(buf),
/*netcontext_flags=*/0);
return std::vector<char>(buf, buf + len);
}
std::vector<char> makeAnswer(const std::vector<char>& query, const char* rdata_str,
const unsigned ttl) {
test::DNSHeader header;
header.read(query.data(), query.data() + query.size());
for (const test::DNSQuestion& question : header.questions) {
std::string rname(question.qname.name);
test::DNSRecord record{
.name = {.name = question.qname.name},
.rtype = question.qtype,
.rclass = question.qclass,
.ttl = ttl,
};
test::DNSResponder::fillRdata(rdata_str, record);
header.answers.push_back(std::move(record));
}
char answer[MAXPACKET] = {};
char* answer_end = header.write(answer, answer + sizeof(answer));
return std::vector<char>(answer, answer_end);
}
// Get the current time in unix timestamp since the Epoch.
time_t currentTime() {
return std::time(nullptr);
}
// Comparison for res_sample.
bool operator==(const res_sample& a, const res_sample& b) {
return std::tie(a.at, a.rtt, a.rcode) == std::tie(b.at, b.rtt, b.rcode);
}
// Comparison for res_stats.
bool operator==(const res_stats& a, const res_stats& b) {
if (std::tie(a.sample_count, a.sample_next) != std::tie(b.sample_count, b.sample_next)) {
return false;
}
for (int i = 0; i < a.sample_count; i++) {
if (a.samples[i] != b.samples[i]) return false;
}
return true;
}
// Comparison for res_params.
bool operator==(const res_params& a, const res_params& b) {
return std::tie(a.sample_validity, a.success_threshold, a.min_samples, a.max_samples,
a.base_timeout_msec, a.retry_count) ==
std::tie(b.sample_validity, b.success_threshold, b.min_samples, b.max_samples,
b.base_timeout_msec, b.retry_count);
}
} // namespace
class ResolvCacheTest : public ::testing::Test {
protected:
static constexpr res_params kParams = {
.sample_validity = 300,
.success_threshold = 25,
.min_samples = 8,
.max_samples = 8,
.base_timeout_msec = 1000,
.retry_count = 2,
};
ResolvCacheTest() {
// Store the default one and conceal 10000+ lines of resolver cache logs.
defaultLogSeverity = android::base::SetMinimumLogSeverity(
static_cast<android::base::LogSeverity>(android::base::WARNING));
}
~ResolvCacheTest() {
cacheDelete(TEST_NETID);
cacheDelete(TEST_NETID_2);
// Restore the log severity.
android::base::SetMinimumLogSeverity(defaultLogSeverity);
}
[[nodiscard]] bool cacheLookup(ResolvCacheStatus expectedCacheStatus, uint32_t netId,
const CacheEntry& ce, uint32_t flags = 0) {
int anslen = 0;
std::vector<char> answer(MAXPACKET);
const auto cacheStatus = resolv_cache_lookup(netId, ce.query.data(), ce.query.size(),
answer.data(), answer.size(), &anslen, flags);
if (cacheStatus != expectedCacheStatus) {
ADD_FAILURE() << "cacheStatus: expected = " << expectedCacheStatus
<< ", actual =" << cacheStatus;
return false;
}
if (cacheStatus == RESOLV_CACHE_FOUND) {
answer.resize(anslen);
if (answer != ce.answer) {
ADD_FAILURE() << "The answer from the cache is not as expected.";
return false;
}
}
return true;
}
int cacheCreate(uint32_t netId) {
return resolv_create_cache_for_net(netId);
}
void cacheDelete(uint32_t netId) {
resolv_delete_cache_for_net(netId);
}
int cacheAdd(uint32_t netId, const CacheEntry& ce) {
return resolv_cache_add(netId, ce.query.data(), ce.query.size(), ce.answer.data(),
ce.answer.size());
}
int cacheAdd(uint32_t netId, const std::vector<char>& query, const std::vector<char>& answer) {
return resolv_cache_add(netId, query.data(), query.size(), answer.data(), answer.size());
}
int cacheGetExpiration(uint32_t netId, const std::vector<char>& query, time_t* expiration) {
return resolv_cache_get_expiration(netId, query, expiration);
}
void cacheQueryFailed(uint32_t netId, const CacheEntry& ce, uint32_t flags) {
_resolv_cache_query_failed(netId, ce.query.data(), ce.query.size(), flags);
}
int cacheSetupResolver(uint32_t netId, const SetupParams& setup) {
return resolv_set_nameservers(netId, setup.servers, setup.domains, setup.params,
setup.resolverOptions, setup.transportTypes);
}
void cacheAddStats(uint32_t netId, int revision_id, const IPSockAddr& ipsa,
const res_sample& sample, int max_samples) {
resolv_cache_add_resolver_stats_sample(netId, revision_id, ipsa, sample, max_samples);
}
int cacheFlush(uint32_t netId) { return resolv_flush_cache_for_net(netId); }
void expectCacheStats(const std::string& msg, uint32_t netId, const CacheStats& expected) {
int nscount = -1;
sockaddr_storage servers[MAXNS];
int dcount = -1;
char domains[MAXDNSRCH][MAXDNSRCHPATH];
res_stats stats[MAXNS];
res_params params = {};
int res_wait_for_pending_req_timeout_count;
android_net_res_stats_get_info_for_net(netId, &nscount, servers, &dcount, domains, ¶ms,
stats, &res_wait_for_pending_req_timeout_count);
// Server checking.
EXPECT_EQ(nscount, static_cast<int>(expected.setup.servers.size())) << msg;
for (int i = 0; i < nscount; i++) {
EXPECT_EQ(ToString(&servers[i]), expected.setup.servers[i]) << msg;
}
// Domain checking
EXPECT_EQ(dcount, static_cast<int>(expected.setup.domains.size())) << msg;
for (int i = 0; i < dcount; i++) {
EXPECT_EQ(std::string(domains[i]), expected.setup.domains[i]) << msg;
}
// res_params checking.
EXPECT_TRUE(params == expected.setup.params) << msg;
// res_stats checking.
if (expected.stats.size() == 0) {
for (int ns = 0; ns < nscount; ns++) {
EXPECT_EQ(0U, stats[ns].sample_count) << msg;
}
}
for (size_t i = 0; i < expected.stats.size(); i++) {
EXPECT_TRUE(stats[i] == expected.stats[i]) << msg;
}
// wait_for_pending_req_timeout_count checking.
EXPECT_EQ(res_wait_for_pending_req_timeout_count, expected.pendingReqTimeoutCount) << msg;
}
CacheEntry makeCacheEntry(int op, const char* qname, int qclass, int qtype, const char* rdata,
std::chrono::seconds ttl = 10s) {
CacheEntry ce;
ce.query = makeQuery(op, qname, qclass, qtype);
ce.answer = makeAnswer(ce.query, rdata, static_cast<unsigned>(ttl.count()));
return ce;
}
private:
android::base::LogSeverity defaultLogSeverity;
};
TEST_F(ResolvCacheTest, CreateAndDeleteCache) {
// Create the cache for network 1.
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(-EEXIST, cacheCreate(TEST_NETID));
EXPECT_TRUE(has_named_cache(TEST_NETID));
// Create the cache for network 2.
EXPECT_EQ(0, cacheCreate(TEST_NETID_2));
EXPECT_EQ(-EEXIST, cacheCreate(TEST_NETID_2));
EXPECT_TRUE(has_named_cache(TEST_NETID_2));
// Delete the cache in network 1.
cacheDelete(TEST_NETID);
EXPECT_FALSE(has_named_cache(TEST_NETID));
EXPECT_TRUE(has_named_cache(TEST_NETID_2));
}
// Missing checks for the argument 'answer'.
TEST_F(ResolvCacheTest, CacheAdd_InvalidArgs) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const std::vector<char> queryEmpty(MAXPACKET, 0);
const std::vector<char> queryTooSmall(DNS_HEADER_SIZE - 1, 0);
CacheEntry ce = makeCacheEntry(QUERY, "valid.cache", ns_c_in, ns_t_a, "1.2.3.4");
EXPECT_EQ(-EINVAL, cacheAdd(TEST_NETID, queryEmpty, ce.answer));
EXPECT_EQ(-EINVAL, cacheAdd(TEST_NETID, queryTooSmall, ce.answer));
// Cache not existent in TEST_NETID_2.
EXPECT_EQ(-ENONET, cacheAdd(TEST_NETID_2, ce));
}
TEST_F(ResolvCacheTest, CacheAdd_DuplicateEntry) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
CacheEntry ce = makeCacheEntry(QUERY, "existent.in.cache", ns_c_in, ns_t_a, "1.2.3.4");
time_t now = currentTime();
// Add the cache entry.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
// Get the expiration time and verify its value is greater than now.
time_t expiration1;
EXPECT_EQ(0, cacheGetExpiration(TEST_NETID, ce.query, &expiration1));
EXPECT_GT(expiration1, now);
// Adding the duplicate entry will return an error, and the expiration time won't be modified.
EXPECT_EQ(-EEXIST, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
time_t expiration2;
EXPECT_EQ(0, cacheGetExpiration(TEST_NETID, ce.query, &expiration2));
EXPECT_EQ(expiration1, expiration2);
}
TEST_F(ResolvCacheTest, CacheLookup) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(0, cacheCreate(TEST_NETID_2));
CacheEntry ce = makeCacheEntry(QUERY, "existent.in.cache", ns_c_in, ns_t_a, "1.2.3.4");
// Cache found in network 1.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
// No cache found in network 2.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID_2, ce));
ce = makeCacheEntry(QUERY, "existent.in.cache", ns_c_in, ns_t_aaaa, "2001:db8::1.2.3.4");
// type A and AAAA are independent.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
}
TEST_F(ResolvCacheTest, CacheLookup_CacheFlags) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
std::vector<char> answerFromCache;
CacheEntry ce = makeCacheEntry(QUERY, "existent.in.cache", ns_c_in, ns_t_a, "1.2.3.4");
// The entry can't be found when only no-cache-lookup bit is carried.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_LOOKUP));
// Ensure RESOLV_CACHE_SKIP is returned when there's no such the same entry in the cache.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_SKIP, TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_STORE));
// Skip the cache lookup if no-cache-lookup and no-cache-store bits are carried
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_SKIP, TEST_NETID, ce,
ANDROID_RESOLV_NO_CACHE_LOOKUP | ANDROID_RESOLV_NO_CACHE_STORE));
// Add the cache entry.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_LOOKUP));
// Now no-cache-store has no effect if a same entry is existent in the cache.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_SKIP, TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_STORE));
// Skip the cache lookup again regardless of a same entry being already in the cache.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_SKIP, TEST_NETID, ce,
ANDROID_RESOLV_NO_CACHE_LOOKUP | ANDROID_RESOLV_NO_CACHE_STORE));
}
TEST_F(ResolvCacheTest, CacheLookup_Types) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
static const struct QueryTypes {
int type;
std::string rdata;
} Types[] = {
{ns_t_a, "1.2.3.4"},
{ns_t_aaaa, "2001:db8::1.2.3.4"},
{ns_t_ptr, "4.3.2.1.in-addr.arpa."},
{ns_t_ptr, "4.0.3.0.2.0.1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa."},
};
for (const auto& t : Types) {
std::string name = android::base::StringPrintf("cache.lookup.type.%s", t.rdata.c_str());
SCOPED_TRACE(name);
CacheEntry ce = makeCacheEntry(QUERY, name.data(), ns_c_in, t.type, t.rdata.data());
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
}
}
TEST_F(ResolvCacheTest, CacheLookup_InvalidArgs) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const std::vector<char> queryEmpty(MAXPACKET, 0);
const std::vector<char> queryTooSmall(DNS_HEADER_SIZE - 1, 0);
std::vector<char> answerTooSmall(DNS_HEADER_SIZE - 1, 0);
const CacheEntry ce = makeCacheEntry(QUERY, "valid.cache", ns_c_in, ns_t_a, "1.2.3.4");
auto cacheLookupFn = [](const std::vector<char>& query,
std::vector<char> answer) -> ResolvCacheStatus {
int anslen = 0;
return resolv_cache_lookup(TEST_NETID, query.data(), query.size(), answer.data(),
answer.size(), &anslen, 0);
};
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_EQ(RESOLV_CACHE_UNSUPPORTED, cacheLookupFn(queryEmpty, ce.answer));
EXPECT_EQ(RESOLV_CACHE_UNSUPPORTED, cacheLookupFn(queryTooSmall, ce.answer));
EXPECT_EQ(RESOLV_CACHE_UNSUPPORTED, cacheLookupFn(ce.query, answerTooSmall));
// It can actually be found with valid arguments.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
// Cache not existent in TEST_NETID_2.
EXPECT_EQ(-ENONET, cacheAdd(TEST_NETID_2, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_UNSUPPORTED, TEST_NETID_2, ce));
}
TEST_F(ResolvCacheTest, CacheLookup_Expired) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
// An entry with zero ttl won't be stored in the cache.
CacheEntry ce = makeCacheEntry(QUERY, "expired.in.0s", ns_c_in, ns_t_a, "1.2.3.4", 0s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
// Create an entry expired in 1s.
ce = makeCacheEntry(QUERY, "expired.in.1s", ns_c_in, ns_t_a, "1.2.3.4", 1s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
// Cache found.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
time_t expiration;
EXPECT_EQ(0, cacheGetExpiration(TEST_NETID, ce.query, &expiration));
// Wait for the cache expired.
std::this_thread::sleep_for(1500ms);
EXPECT_GE(currentTime(), expiration);
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
}
TEST_F(ResolvCacheTest, PendingRequest_QueryDeferred) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(0, cacheCreate(TEST_NETID_2));
CacheEntry ce = makeCacheEntry(QUERY, "query.deferred", ns_c_in, ns_t_a, "1.2.3.4");
std::atomic_bool done(false);
// This is the first lookup. The following lookups from other threads will be in the
// pending request list.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
std::vector<std::thread> threads(5);
for (std::thread& thread : threads) {
thread = std::thread([&]() {
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
// Ensure this thread gets stuck in lookups before we wake it.
EXPECT_TRUE(done);
});
}
// Wait for a while for the threads performing lookups.
// TODO: Perhaps implement a test-only function to get the number of pending requests
// instead of sleep.
std::this_thread::sleep_for(100ms);
// The threads keep waiting regardless of any other networks or even if cache flag is set.
EXPECT_EQ(0, cacheAdd(TEST_NETID_2, ce));
cacheQueryFailed(TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_STORE);
cacheQueryFailed(TEST_NETID, ce, ANDROID_RESOLV_NO_CACHE_LOOKUP);
cacheQueryFailed(TEST_NETID_2, ce, ANDROID_RESOLV_NO_CACHE_STORE);
cacheQueryFailed(TEST_NETID_2, ce, ANDROID_RESOLV_NO_CACHE_LOOKUP);
cacheDelete(TEST_NETID_2);
// Ensure none of the threads has finished the lookups.
std::this_thread::sleep_for(100ms);
// Wake up the threads
done = true;
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
for (std::thread& thread : threads) {
thread.join();
}
}
TEST_F(ResolvCacheTest, PendingRequest_QueryFailed) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
CacheEntry ce = makeCacheEntry(QUERY, "query.failed", ns_c_in, ns_t_a, "1.2.3.4");
std::atomic_bool done(false);
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
std::vector<std::thread> threads(5);
for (std::thread& thread : threads) {
thread = std::thread([&]() {
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
// Ensure this thread gets stuck in lookups before we wake it.
EXPECT_TRUE(done);
});
}
// Wait for a while for the threads performing lookups.
std::this_thread::sleep_for(100ms);
// Wake up the threads
done = true;
cacheQueryFailed(TEST_NETID, ce, 0);
for (std::thread& thread : threads) {
thread.join();
}
}
TEST_F(ResolvCacheTest, PendingRequest_CacheDestroyed) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(0, cacheCreate(TEST_NETID_2));
CacheEntry ce = makeCacheEntry(QUERY, "query.failed", ns_c_in, ns_t_a, "1.2.3.4");
std::atomic_bool done(false);
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
std::vector<std::thread> threads(5);
for (std::thread& thread : threads) {
thread = std::thread([&]() {
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce));
// Ensure this thread gets stuck in lookups before we wake it.
EXPECT_TRUE(done);
});
}
// Wait for a while for the threads performing lookups.
std::this_thread::sleep_for(100ms);
// Deleting another network must not cause the threads to wake up.
cacheDelete(TEST_NETID_2);
// Ensure none of the threads has finished the lookups.
std::this_thread::sleep_for(100ms);
// Wake up the threads
done = true;
cacheDelete(TEST_NETID);
for (std::thread& thread : threads) {
thread.join();
}
}
TEST_F(ResolvCacheTest, MaxEntries) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
std::vector<CacheEntry> ces;
for (int i = 0; i < 2 * MAX_ENTRIES; i++) {
std::string qname = android::base::StringPrintf("cache.%04d", i);
SCOPED_TRACE(qname);
CacheEntry ce = makeCacheEntry(QUERY, qname.data(), ns_c_in, ns_t_a, "1.2.3.4");
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
ces.emplace_back(ce);
}
for (int i = 0; i < 2 * MAX_ENTRIES; i++) {
std::string qname = android::base::StringPrintf("cache.%04d", i);
SCOPED_TRACE(qname);
if (i < MAX_ENTRIES) {
// Because the cache is LRU, the oldest queries should have been purged,
// and the most recent MAX_ENTRIES ones should still be present.
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ces[i]));
} else {
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ces[i]));
}
}
}
TEST_F(ResolvCacheTest, CacheFull) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
CacheEntry ce1 = makeCacheEntry(QUERY, "cache.0000", ns_c_in, ns_t_a, "1.2.3.4", 100s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce1));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce1));
CacheEntry ce2 = makeCacheEntry(QUERY, "cache.0001", ns_c_in, ns_t_a, "1.2.3.4", 1s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce2));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce2));
// Stuff the resolver cache.
for (int i = 2; i < MAX_ENTRIES; i++) {
std::string qname = android::base::StringPrintf("cache.%04d", i);
SCOPED_TRACE(qname);
CacheEntry ce = makeCacheEntry(QUERY, qname.data(), ns_c_in, ns_t_a, "1.2.3.4", 50s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce));
}
// Wait for ce2 expired.
std::this_thread::sleep_for(1500ms);
// The cache is full now, and the expired ce2 will be removed first.
CacheEntry ce3 = makeCacheEntry(QUERY, "cache.overfilled.1", ns_c_in, ns_t_a, "1.2.3.4", 50s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce3));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce3));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce2));
// The cache is full again but there's no one expired, so the oldest ce1 will be removed.
CacheEntry ce4 = makeCacheEntry(QUERY, "cache.overfilled.2", ns_c_in, ns_t_a, "1.2.3.4", 50s);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce4));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_FOUND, TEST_NETID, ce4));
EXPECT_TRUE(cacheLookup(RESOLV_CACHE_NOTFOUND, TEST_NETID, ce1));
}
TEST_F(ResolvCacheTest, ResolverSetup) {
const SetupParams setup = {
.servers = {"127.0.0.1", "::127.0.0.2", "fe80::3"},
.domains = {"domain1.com", "domain2.com"},
.params = kParams,
};
// Failed to setup resolver because of the cache not created.
EXPECT_EQ(-ENONET, cacheSetupResolver(TEST_NETID, setup));
EXPECT_FALSE(resolv_has_nameservers(TEST_NETID));
// The cache is created now.
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
}
TEST_F(ResolvCacheTest, ResolverSetup_InvalidNameServers) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const std::string invalidServers[]{
"127.A.b.1",
"127.^.0",
"::^:1",
"",
};
SetupParams setup = {
.servers = {},
.domains = {"domain1.com"},
.params = kParams,
};
// Failed to setup resolver because of invalid name servers.
for (const auto& server : invalidServers) {
SCOPED_TRACE(server);
setup.servers = {"127.0.0.1", server, "127.0.0.2"};
EXPECT_EQ(-EINVAL, cacheSetupResolver(TEST_NETID, setup));
EXPECT_FALSE(resolv_has_nameservers(TEST_NETID));
}
}
TEST_F(ResolvCacheTest, ResolverSetup_DropDomain) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
// Setup with one domain which is too long.
const std::vector<std::string> servers = {"127.0.0.1", "fe80::1"};
const std::string domainTooLong(MAXDNSRCHPATH, '1');
const std::string validDomain1(MAXDNSRCHPATH - 1, '2');
const std::string validDomain2(MAXDNSRCHPATH - 1, '3');
SetupParams setup = {
.servers = servers,
.domains = {},
.params = kParams,
};
CacheStats expect = {
.setup = setup,
.stats = {},
.pendingReqTimeoutCount = 0,
};
// Overlength domains are dropped.
setup.domains = {validDomain1, domainTooLong, validDomain2};
expect.setup.domains = {validDomain1, validDomain2};
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
expectCacheStats("ResolverSetup_Domains drop overlength", TEST_NETID, expect);
// Duplicate domains are dropped.
setup.domains = {validDomain1, validDomain2, validDomain1, validDomain2};
expect.setup.domains = {validDomain1, validDomain2};
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
expectCacheStats("ResolverSetup_Domains drop duplicates", TEST_NETID, expect);
}
TEST_F(ResolvCacheTest, ResolverSetup_Prune) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const std::vector<std::string> servers = {"127.0.0.1", "::127.0.0.2", "fe80::1", "fe80::2",
"fe80::3"};
const std::vector<std::string> domains = {"d1.com", "d2.com", "d3.com", "d4.com",
"d5.com", "d6.com", "d7.com"};
const SetupParams setup = {
.servers = servers,
.domains = domains,
.params = kParams,
};
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
const CacheStats cacheStats = {
.setup = {.servers = std::vector(servers.begin(), servers.begin() + MAXNS),
.domains = std::vector(domains.begin(), domains.begin() + MAXDNSRCH),
.params = setup.params},
.stats = {},
.pendingReqTimeoutCount = 0,
};
expectCacheStats("ResolverSetup_Prune", TEST_NETID, cacheStats);
}
TEST_F(ResolvCacheTest, GetStats) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const SetupParams setup = {
.servers = {"127.0.0.1", "::127.0.0.2", "fe80::3"},
.domains = {"domain1.com", "domain2.com"},
.params = kParams,
};
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
const CacheStats cacheStats = {
.setup = setup,
.stats = {},
.pendingReqTimeoutCount = 0,
};
expectCacheStats("GetStats", TEST_NETID, cacheStats);
}
TEST_F(ResolvCacheTest, FlushCache) {
EXPECT_EQ(0, cacheCreate(TEST_NETID));
const SetupParams setup = {
.servers = {"127.0.0.1", "::127.0.0.2", "fe80::3"},
.domains = {"domain1.com", "domain2.com"},
.params = kParams,
};
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
EXPECT_TRUE(resolv_has_nameservers(TEST_NETID));
res_sample sample = {.at = time(NULL), .rtt = 100, .rcode = ns_r_noerror};
sockaddr_in sin = {.sin_family = AF_INET, .sin_port = htons(DNS_PORT)};
ASSERT_TRUE(inet_pton(AF_INET, setup.servers[0].c_str(), &sin.sin_addr));
cacheAddStats(TEST_NETID, 1 /*revision_id*/, IPSockAddr(sin), sample, setup.params.max_samples);
const CacheStats cacheStats = {
.setup = setup,
.stats = {{{sample}, 1 /*sample_count*/, 1 /*sample_next*/}},
.pendingReqTimeoutCount = 0,
};
expectCacheStats("FlushCache: a record in cache stats", TEST_NETID, cacheStats);
EXPECT_EQ(0, cacheFlush(TEST_NETID));
const CacheStats cacheStats_empty = {
.setup = setup,
.stats = {},
.pendingReqTimeoutCount = 0,
};
expectCacheStats("FlushCache: no record in cache stats", TEST_NETID, cacheStats_empty);
}
TEST_F(ResolvCacheTest, GetHostByAddrFromCache_InvalidArgs) {
char domain_name[NS_MAXDNAME] = {};
const char query_v4[] = "1.2.3.5";
// invalid buffer size
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME + 1, nullptr,
AF_INET));
EXPECT_STREQ("", domain_name);
// invalid query
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, nullptr,
AF_INET));
EXPECT_STREQ("", domain_name);
// unsupported AF
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v4,
AF_UNSPEC));
EXPECT_STREQ("", domain_name);
}
TEST_F(ResolvCacheTest, GetHostByAddrFromCache) {
char domain_name[NS_MAXDNAME] = {};
const char query_v4[] = "1.2.3.5";
const char query_v6[] = "2001:db8::102:304";
const char query_v6_unabbreviated[] = "2001:0db8:0000:0000:0000:0000:0102:0304";
const char query_v6_mixed[] = "2001:db8::1.2.3.4";
const char answer[] = "existent.in.cache";
// cache does not exist
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v4,
AF_INET));
EXPECT_STREQ("", domain_name);
// cache is empty
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v4,
AF_INET));
EXPECT_STREQ("", domain_name);
// no v4 match in cache
CacheEntry ce = makeCacheEntry(QUERY, "any.data", ns_c_in, ns_t_a, "1.2.3.4");
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v4,
AF_INET));
EXPECT_STREQ("", domain_name);
// v4 match
ce = makeCacheEntry(QUERY, answer, ns_c_in, ns_t_a, query_v4);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v4,
AF_INET));
EXPECT_STREQ(answer, domain_name);
// no v6 match in cache
memset(domain_name, 0, NS_MAXDNAME);
EXPECT_FALSE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v6,
AF_INET6));
EXPECT_STREQ("", domain_name);
// v6 match
ce = makeCacheEntry(QUERY, answer, ns_c_in, ns_t_aaaa, query_v6);
EXPECT_EQ(0, cacheAdd(TEST_NETID, ce));
EXPECT_TRUE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME, query_v6,
AF_INET6));
EXPECT_STREQ(answer, domain_name);
// v6 match with unabbreviated address format
memset(domain_name, 0, NS_MAXDNAME);
EXPECT_TRUE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME,
query_v6_unabbreviated, AF_INET6));
EXPECT_STREQ(answer, domain_name);
// v6 with mixed address format
memset(domain_name, 0, NS_MAXDNAME);
EXPECT_TRUE(resolv_gethostbyaddr_from_cache(TEST_NETID, domain_name, NS_MAXDNAME,
query_v6_mixed, AF_INET6));
EXPECT_STREQ(answer, domain_name);
}
TEST_F(ResolvCacheTest, GetResolverStats) {
const res_sample sample1 = {.at = time(nullptr), .rtt = 100, .rcode = ns_r_noerror};
const res_sample sample2 = {.at = time(nullptr), .rtt = 200, .rcode = ns_r_noerror};
const res_sample sample3 = {.at = time(nullptr), .rtt = 300, .rcode = ns_r_noerror};
const res_stats expectedStats[MAXNS] = {
{{sample1}, 1 /*sample_count*/, 1 /*sample_next*/},
{{sample2}, 1, 1},
{{sample3}, 1, 1},
};
std::vector<IPSockAddr> nameserverSockAddrs = {
IPSockAddr::toIPSockAddr("127.0.0.1", DNS_PORT),
IPSockAddr::toIPSockAddr("::127.0.0.2", DNS_PORT),
IPSockAddr::toIPSockAddr("fe80::3", DNS_PORT),
};
const SetupParams setup = {
.servers = {"127.0.0.1", "::127.0.0.2", "fe80::3"},
.domains = {"domain1.com", "domain2.com"},
.params = kParams,
};
EXPECT_EQ(0, cacheCreate(TEST_NETID));
EXPECT_EQ(0, cacheSetupResolver(TEST_NETID, setup));
int revision_id = 1;
cacheAddStats(TEST_NETID, revision_id, nameserverSockAddrs[0], sample1,
setup.params.max_samples);
cacheAddStats(TEST_NETID, revision_id, nameserverSockAddrs[1], sample2,
setup.params.max_samples);
cacheAddStats(TEST_NETID, revision_id, nameserverSockAddrs[2], sample3,
setup.params.max_samples);
res_stats cacheStats[MAXNS]{};
res_params params;
EXPECT_EQ(resolv_cache_get_resolver_stats(TEST_NETID, ¶ms, cacheStats, nameserverSockAddrs),
revision_id);
EXPECT_TRUE(params == kParams);
for (size_t i = 0; i < MAXNS; i++) {
EXPECT_TRUE(cacheStats[i] == expectedStats[i]);
}
// pass another list of IPSockAddr
const res_stats expectedStats2[MAXNS] = {
{{sample3, sample2}, 2, 2},
{{sample2}, 1, 1},
{{sample1}, 1, 1},
};
nameserverSockAddrs = {
IPSockAddr::toIPSockAddr("fe80::3", DNS_PORT),
IPSockAddr::toIPSockAddr("::127.0.0.2", DNS_PORT),
IPSockAddr::toIPSockAddr("127.0.0.1", DNS_PORT),
};
cacheAddStats(TEST_NETID, revision_id, nameserverSockAddrs[0], sample2,
setup.params.max_samples);
EXPECT_EQ(resolv_cache_get_resolver_stats(TEST_NETID, ¶ms, cacheStats, nameserverSockAddrs),
revision_id);
EXPECT_TRUE(params == kParams);
for (size_t i = 0; i < MAXNS; i++) {
EXPECT_TRUE(cacheStats[i] == expectedStats2[i]);
}
}
namespace {
constexpr int EAI_OK = 0;
constexpr char DNS_EVENT_SUBSAMPLING_MAP_FLAG[] =
"persist.device_config.netd_native.dns_event_subsample_map";
class ScopedCacheCreate {
public:
explicit ScopedCacheCreate(unsigned netid, const char* subsampling_map,
const char* property = DNS_EVENT_SUBSAMPLING_MAP_FLAG)
: mStoredNetId(netid), mStoredProperty(property) {
property_get(property, mStoredMap, "");
property_set(property, subsampling_map);
EXPECT_EQ(0, resolv_create_cache_for_net(netid));
}
~ScopedCacheCreate() {
resolv_delete_cache_for_net(mStoredNetId);
property_set(mStoredProperty, mStoredMap);
}
private:
unsigned mStoredNetId;
const char* mStoredProperty;
char mStoredMap[PROPERTY_VALUE_MAX]{};
};
} // namespace
TEST_F(ResolvCacheTest, DnsEventSubsampling) {
// Test defaults, default flag is "default:8 0:400 2:110 7:110" if no experiment flag is set
{
ScopedCacheCreate scopedCacheCreate(TEST_NETID, "");
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_AGAIN), 110U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_NODATA), 110U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_OK), 400U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_BADFLAGS),
8U); // default
EXPECT_THAT(resolv_cache_dump_subsampling_map(TEST_NETID),
testing::UnorderedElementsAreArray({"default:8", "0:400", "2:110", "7:110"}));
}
// Now change the experiment flag to "0:42 default:666"
{
ScopedCacheCreate scopedCacheCreate(TEST_NETID, "0:42 default:666");
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_OK), 42U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_NODATA),
666U); // default
EXPECT_THAT(resolv_cache_dump_subsampling_map(TEST_NETID),
testing::UnorderedElementsAreArray({"default:666", "0:42"}));
}
// Now change the experiment flag to something illegal
{
ScopedCacheCreate scopedCacheCreate(TEST_NETID, "asvaxx");
// 0(disable log) is the default value if experiment flag is invalid.
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_OK), 0U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_NODATA), 0U);
EXPECT_TRUE(resolv_cache_dump_subsampling_map(TEST_NETID).empty());
}
// Test negative and zero denom
{
ScopedCacheCreate scopedCacheCreate(TEST_NETID, "0:-42 default:-666 7:10 10:0");
// 0(disable log) is the default value if no valid denom is set
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_OK), 0U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_BADFLAGS), 0U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_NODATA), 10U);
EXPECT_EQ(resolv_cache_get_subsampling_denom(TEST_NETID, EAI_SOCKTYPE), 0U);
EXPECT_THAT(resolv_cache_dump_subsampling_map(TEST_NETID),
testing::UnorderedElementsAreArray({"7:10", "10:0"}));
}
}
// TODO: Tests for NetConfig, including:
// - res_stats
// -- _resolv_cache_add_resolver_stats_sample()
// -- android_net_res_stats_get_info_for_net()
// TODO: inject a mock timer into the cache to make TTL tests pass instantly
// TODO: test TTL of RFC 2308 negative caching