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-rw-r--r--netwerk/dns/nsHostResolver.cpp2325
1 files changed, 2325 insertions, 0 deletions
diff --git a/netwerk/dns/nsHostResolver.cpp b/netwerk/dns/nsHostResolver.cpp
new file mode 100644
index 0000000000..268e2ec38b
--- /dev/null
+++ b/netwerk/dns/nsHostResolver.cpp
@@ -0,0 +1,2325 @@
+/* vim:set ts=4 sw=2 sts=2 et cin: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if defined(HAVE_RES_NINIT)
+# include <sys/types.h>
+# include <netinet/in.h>
+# include <arpa/inet.h>
+# include <arpa/nameser.h>
+# include <resolv.h>
+# define RES_RETRY_ON_FAILURE
+#endif
+
+#include <stdlib.h>
+#include <ctime>
+#include "nsHostResolver.h"
+#include "nsError.h"
+#include "nsISupportsBase.h"
+#include "nsISupportsUtils.h"
+#include "nsIThreadManager.h"
+#include "nsComponentManagerUtils.h"
+#include "nsNetUtil.h"
+#include "nsPrintfCString.h"
+#include "nsXPCOMCIDInternal.h"
+#include "prthread.h"
+#include "prerror.h"
+#include "prtime.h"
+#include "mozilla/Logging.h"
+#include "PLDHashTable.h"
+#include "plstr.h"
+#include "nsQueryObject.h"
+#include "nsURLHelper.h"
+#include "nsThreadUtils.h"
+#include "nsThreadPool.h"
+#include "GetAddrInfo.h"
+#include "GeckoProfiler.h"
+#include "TRR.h"
+#include "TRRQuery.h"
+#include "TRRService.h"
+
+#include "mozilla/Atomics.h"
+#include "mozilla/HashFunctions.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/StaticPrefs_network.h"
+
+using namespace mozilla;
+using namespace mozilla::net;
+
+// None of our implementations expose a TTL for negative responses, so we use a
+// constant always.
+static const unsigned int NEGATIVE_RECORD_LIFETIME = 60;
+
+//----------------------------------------------------------------------------
+
+// Use a persistent thread pool in order to avoid spinning up new threads all
+// the time. In particular, thread creation results in a res_init() call from
+// libc which is quite expensive.
+//
+// The pool dynamically grows between 0 and MAX_RESOLVER_THREADS in size. New
+// requests go first to an idle thread. If that cannot be found and there are
+// fewer than MAX_RESOLVER_THREADS currently in the pool a new thread is created
+// for high priority requests. If the new request is at a lower priority a new
+// thread will only be created if there are fewer than HighThreadThreshold
+// currently outstanding. If a thread cannot be created or an idle thread
+// located for the request it is queued.
+//
+// When the pool is greater than HighThreadThreshold in size a thread will be
+// destroyed after ShortIdleTimeoutSeconds of idle time. Smaller pools use
+// LongIdleTimeoutSeconds for a timeout period.
+
+#define HighThreadThreshold MAX_RESOLVER_THREADS_FOR_ANY_PRIORITY
+#define LongIdleTimeoutSeconds 300 // for threads 1 -> HighThreadThreshold
+#define ShortIdleTimeoutSeconds \
+ 60 // for threads HighThreadThreshold+1 -> MAX_RESOLVER_THREADS
+
+static_assert(
+ HighThreadThreshold <= MAX_RESOLVER_THREADS,
+ "High Thread Threshold should be less equal Maximum allowed thread");
+
+//----------------------------------------------------------------------------
+
+namespace mozilla::net {
+LazyLogModule gHostResolverLog("nsHostResolver");
+#define LOG(args) \
+ MOZ_LOG(mozilla::net::gHostResolverLog, mozilla::LogLevel::Debug, args)
+#define LOG1(args) \
+ MOZ_LOG(mozilla::net::gHostResolverLog, mozilla::LogLevel::Error, args)
+#define LOG_ENABLED() \
+ MOZ_LOG_TEST(mozilla::net::gHostResolverLog, mozilla::LogLevel::Debug)
+} // namespace mozilla::net
+
+//----------------------------------------------------------------------------
+
+#if defined(RES_RETRY_ON_FAILURE)
+
+// this class represents the resolver state for a given thread. if we
+// encounter a lookup failure, then we can invoke the Reset method on an
+// instance of this class to reset the resolver (in case /etc/resolv.conf
+// for example changed). this is mainly an issue on GNU systems since glibc
+// only reads in /etc/resolv.conf once per thread. it may be an issue on
+// other systems as well.
+
+class nsResState {
+ public:
+ nsResState()
+ // initialize mLastReset to the time when this object
+ // is created. this means that a reset will not occur
+ // if a thread is too young. the alternative would be
+ // to initialize this to the beginning of time, so that
+ // the first failure would cause a reset, but since the
+ // thread would have just started up, it likely would
+ // already have current /etc/resolv.conf info.
+ : mLastReset(PR_IntervalNow()) {}
+
+ bool Reset() {
+ // reset no more than once per second
+ if (PR_IntervalToSeconds(PR_IntervalNow() - mLastReset) < 1) {
+ return false;
+ }
+
+ LOG(("Calling 'res_ninit'.\n"));
+
+ mLastReset = PR_IntervalNow();
+ return (res_ninit(&_res) == 0);
+ }
+
+ private:
+ PRIntervalTime mLastReset;
+};
+
+#endif // RES_RETRY_ON_FAILURE
+
+//----------------------------------------------------------------------------
+
+static inline bool IsHighPriority(uint16_t flags) {
+ return !(flags & (nsHostResolver::RES_PRIORITY_LOW |
+ nsHostResolver::RES_PRIORITY_MEDIUM));
+}
+
+static inline bool IsMediumPriority(uint16_t flags) {
+ return flags & nsHostResolver::RES_PRIORITY_MEDIUM;
+}
+
+static inline bool IsLowPriority(uint16_t flags) {
+ return flags & nsHostResolver::RES_PRIORITY_LOW;
+}
+
+//----------------------------------------------------------------------------
+// this macro filters out any flags that are not used when constructing the
+// host key. the significant flags are those that would affect the resulting
+// host record (i.e., the flags that are passed down to PR_GetAddrInfoByName).
+#define RES_KEY_FLAGS(_f) \
+ ((_f) & \
+ (nsHostResolver::RES_CANON_NAME | nsHostResolver::RES_DISABLE_TRR | \
+ nsIDNSService::RESOLVE_TRR_MODE_MASK | nsHostResolver::RES_IP_HINT))
+
+#define IS_ADDR_TYPE(_type) ((_type) == nsIDNSService::RESOLVE_TYPE_DEFAULT)
+#define IS_OTHER_TYPE(_type) ((_type) != nsIDNSService::RESOLVE_TYPE_DEFAULT)
+
+nsHostKey::nsHostKey(const nsACString& aHost, const nsACString& aTrrServer,
+ uint16_t aType, uint16_t aFlags, uint16_t aAf, bool aPb,
+ const nsACString& aOriginsuffix)
+ : host(aHost),
+ mTrrServer(aTrrServer),
+ type(aType),
+ flags(aFlags),
+ af(aAf),
+ pb(aPb),
+ originSuffix(aOriginsuffix) {}
+
+bool nsHostKey::operator==(const nsHostKey& other) const {
+ return host == other.host && mTrrServer == other.mTrrServer &&
+ type == other.type &&
+ RES_KEY_FLAGS(flags) == RES_KEY_FLAGS(other.flags) && af == other.af &&
+ originSuffix == other.originSuffix;
+}
+
+PLDHashNumber nsHostKey::Hash() const {
+ return AddToHash(HashString(host.get()), HashString(mTrrServer.get()), type,
+ RES_KEY_FLAGS(flags), af, HashString(originSuffix.get()));
+}
+
+size_t nsHostKey::SizeOfExcludingThis(
+ mozilla::MallocSizeOf mallocSizeOf) const {
+ size_t n = 0;
+ n += host.SizeOfExcludingThisIfUnshared(mallocSizeOf);
+ n += mTrrServer.SizeOfExcludingThisIfUnshared(mallocSizeOf);
+ n += originSuffix.SizeOfExcludingThisIfUnshared(mallocSizeOf);
+ return n;
+}
+
+NS_IMPL_ISUPPORTS0(nsHostRecord)
+
+nsHostRecord::nsHostRecord(const nsHostKey& key)
+ : nsHostKey(key),
+ mEffectiveTRRMode(nsIRequest::TRR_DEFAULT_MODE),
+ mTRRQuery("nsHostRecord.mTRRQuery"),
+ mResolving(0),
+ negative(false),
+ mDoomed(false) {}
+
+void nsHostRecord::Invalidate() { mDoomed = true; }
+
+void nsHostRecord::Cancel() {
+ RefPtr<TRRQuery> query;
+ {
+ auto lock = mTRRQuery.Lock();
+ query.swap(lock.ref());
+ }
+
+ if (query) {
+ query->Cancel();
+ }
+}
+
+nsHostRecord::ExpirationStatus nsHostRecord::CheckExpiration(
+ const mozilla::TimeStamp& now) const {
+ if (!mGraceStart.IsNull() && now >= mGraceStart && !mValidEnd.IsNull() &&
+ now < mValidEnd) {
+ return nsHostRecord::EXP_GRACE;
+ }
+ if (!mValidEnd.IsNull() && now < mValidEnd) {
+ return nsHostRecord::EXP_VALID;
+ }
+
+ return nsHostRecord::EXP_EXPIRED;
+}
+
+void nsHostRecord::SetExpiration(const mozilla::TimeStamp& now,
+ unsigned int valid, unsigned int grace) {
+ mValidStart = now;
+ if ((valid + grace) < 60) {
+ grace = 60 - valid;
+ LOG(("SetExpiration: artificially bumped grace to %d\n", grace));
+ }
+ mGraceStart = now + TimeDuration::FromSeconds(valid);
+ mValidEnd = now + TimeDuration::FromSeconds(valid + grace);
+}
+
+void nsHostRecord::CopyExpirationTimesAndFlagsFrom(
+ const nsHostRecord* aFromHostRecord) {
+ // This is used to copy information from a cache entry to a record. All
+ // information necessary for HasUsableRecord needs to be copied.
+ mValidStart = aFromHostRecord->mValidStart;
+ mValidEnd = aFromHostRecord->mValidEnd;
+ mGraceStart = aFromHostRecord->mGraceStart;
+ mDoomed = aFromHostRecord->mDoomed;
+}
+
+bool nsHostRecord::HasUsableResult(const mozilla::TimeStamp& now,
+ uint16_t queryFlags) const {
+ if (mDoomed) {
+ return false;
+ }
+
+ // don't use cached negative results for high priority queries.
+ if (negative && IsHighPriority(queryFlags)) {
+ return false;
+ }
+
+ if (CheckExpiration(now) == EXP_EXPIRED) {
+ return false;
+ }
+
+ if (negative) {
+ return true;
+ }
+
+ return HasUsableResultInternal();
+}
+
+static size_t SizeOfResolveHostCallbackListExcludingHead(
+ const mozilla::LinkedList<RefPtr<nsResolveHostCallback>>& aCallbacks,
+ MallocSizeOf mallocSizeOf) {
+ size_t n = aCallbacks.sizeOfExcludingThis(mallocSizeOf);
+
+ for (const nsResolveHostCallback* t = aCallbacks.getFirst(); t;
+ t = t->getNext()) {
+ n += t->SizeOfIncludingThis(mallocSizeOf);
+ }
+
+ return n;
+}
+
+NS_IMPL_ISUPPORTS_INHERITED(AddrHostRecord, nsHostRecord, AddrHostRecord)
+
+AddrHostRecord::AddrHostRecord(const nsHostKey& key)
+ : nsHostRecord(key),
+ addr_info_lock("AddrHostRecord.addr_info_lock"),
+ addr_info_gencnt(0),
+ addr_info(nullptr),
+ addr(nullptr),
+ mTRRUsed(false),
+ mTRRSuccess(0),
+ mNativeSuccess(0) {}
+
+AddrHostRecord::~AddrHostRecord() {
+ mCallbacks.clear();
+ Telemetry::Accumulate(Telemetry::DNS_BLACKLIST_COUNT, mUnusableCount);
+}
+
+bool AddrHostRecord::Blocklisted(const NetAddr* aQuery) {
+ addr_info_lock.AssertCurrentThreadOwns();
+ LOG(("Checking unusable list for host [%s], host record [%p].\n", host.get(),
+ this));
+
+ // skip the string conversion for the common case of no blocklist
+ if (!mUnusableItems.Length()) {
+ return false;
+ }
+
+ char buf[kIPv6CStrBufSize];
+ if (!aQuery->ToStringBuffer(buf, sizeof(buf))) {
+ return false;
+ }
+ nsDependentCString strQuery(buf);
+
+ for (uint32_t i = 0; i < mUnusableItems.Length(); i++) {
+ if (mUnusableItems.ElementAt(i).Equals(strQuery)) {
+ LOG(("Address [%s] is blocklisted for host [%s].\n", buf, host.get()));
+ return true;
+ }
+ }
+
+ return false;
+}
+
+void AddrHostRecord::ReportUnusable(const NetAddr* aAddress) {
+ addr_info_lock.AssertCurrentThreadOwns();
+ LOG(
+ ("Adding address to blocklist for host [%s], host record [%p]."
+ "used trr=%d\n",
+ host.get(), this, mTRRSuccess));
+
+ ++mUnusableCount;
+
+ char buf[kIPv6CStrBufSize];
+ if (aAddress->ToStringBuffer(buf, sizeof(buf))) {
+ LOG(
+ ("Successfully adding address [%s] to blocklist for host "
+ "[%s].\n",
+ buf, host.get()));
+ mUnusableItems.AppendElement(nsCString(buf));
+ }
+}
+
+void AddrHostRecord::ResetBlocklist() {
+ addr_info_lock.AssertCurrentThreadOwns();
+ LOG(("Resetting blocklist for host [%s], host record [%p].\n", host.get(),
+ this));
+ mUnusableItems.Clear();
+}
+
+size_t AddrHostRecord::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) const {
+ size_t n = mallocSizeOf(this);
+
+ n += nsHostKey::SizeOfExcludingThis(mallocSizeOf);
+ n += SizeOfResolveHostCallbackListExcludingHead(mCallbacks, mallocSizeOf);
+
+ n += addr_info ? addr_info->SizeOfIncludingThis(mallocSizeOf) : 0;
+ n += mallocSizeOf(addr.get());
+
+ n += mUnusableItems.ShallowSizeOfExcludingThis(mallocSizeOf);
+ for (size_t i = 0; i < mUnusableItems.Length(); i++) {
+ n += mUnusableItems[i].SizeOfExcludingThisIfUnshared(mallocSizeOf);
+ }
+ return n;
+}
+
+bool AddrHostRecord::HasUsableResultInternal() const {
+ return addr_info || addr;
+}
+
+// Returns true if the entry can be removed, or false if it should be left.
+// Sets ResolveAgain true for entries being resolved right now.
+bool AddrHostRecord::RemoveOrRefresh(bool aTrrToo) {
+ // no need to flush TRRed names, they're not resolved "locally"
+ MutexAutoLock lock(addr_info_lock);
+ if (addr_info && !aTrrToo && addr_info->IsTRR()) {
+ return false;
+ }
+ if (LoadNative()) {
+ if (!onQueue()) {
+ // The request has been passed to the OS resolver. The resultant DNS
+ // record should be considered stale and not trusted; set a flag to
+ // ensure it is called again.
+ StoreResolveAgain(true);
+ }
+ // if onQueue is true, the host entry is already added to the cache
+ // but is still pending to get resolved: just leave it in hash.
+ return false;
+ }
+ // Already resolved; not in a pending state; remove from cache
+ return true;
+}
+
+void AddrHostRecord::ResolveComplete() {
+ if (LoadNativeUsed()) {
+ if (mNativeSuccess) {
+ uint32_t millis = static_cast<uint32_t>(mNativeDuration.ToMilliseconds());
+ Telemetry::Accumulate(Telemetry::DNS_NATIVE_LOOKUP_TIME, millis);
+ }
+ AccumulateCategoricalKeyed(
+ TRRService::AutoDetectedKey(),
+ mNativeSuccess ? Telemetry::LABELS_DNS_LOOKUP_DISPOSITION2::osOK
+ : Telemetry::LABELS_DNS_LOOKUP_DISPOSITION2::osFail);
+ }
+
+ if (mTRRUsed) {
+ if (mTRRSuccess) {
+ uint32_t millis = static_cast<uint32_t>(mTrrDuration.ToMilliseconds());
+ Telemetry::Accumulate(Telemetry::DNS_TRR_LOOKUP_TIME2,
+ TRRService::AutoDetectedKey(), millis);
+ }
+ AccumulateCategoricalKeyed(
+ TRRService::AutoDetectedKey(),
+ mTRRSuccess ? Telemetry::LABELS_DNS_LOOKUP_DISPOSITION2::trrOK
+ : Telemetry::LABELS_DNS_LOOKUP_DISPOSITION2::trrFail);
+ }
+
+ if (nsHostResolver::Mode() == MODE_TRRFIRST) {
+ Telemetry::Accumulate(Telemetry::TRR_SKIP_REASON_TRR_FIRST,
+ mTRRTRRSkippedReason);
+
+ if (mNativeSuccess) {
+ Telemetry::Accumulate(Telemetry::TRR_SKIP_REASON_DNS_WORKED,
+ mTRRTRRSkippedReason);
+ }
+ }
+
+ if (mEffectiveTRRMode == nsIRequest::TRR_FIRST_MODE) {
+ if (flags & nsIDNSService::RESOLVE_DISABLE_TRR) {
+ // TRR is disabled on request, which is a next-level back-off method.
+ Telemetry::Accumulate(Telemetry::DNS_TRR_DISABLED2,
+ TRRService::AutoDetectedKey(), mNativeSuccess);
+ } else {
+ if (mTRRSuccess) {
+ AccumulateCategoricalKeyed(TRRService::AutoDetectedKey(),
+ Telemetry::LABELS_DNS_TRR_FIRST3::TRR);
+ } else if (mNativeSuccess) {
+ if (mTRRUsed) {
+ AccumulateCategoricalKeyed(
+ TRRService::AutoDetectedKey(),
+ Telemetry::LABELS_DNS_TRR_FIRST3::NativeAfterTRR);
+ } else {
+ AccumulateCategoricalKeyed(TRRService::AutoDetectedKey(),
+ Telemetry::LABELS_DNS_TRR_FIRST3::Native);
+ }
+ } else {
+ AccumulateCategoricalKeyed(
+ TRRService::AutoDetectedKey(),
+ Telemetry::LABELS_DNS_TRR_FIRST3::BothFailed);
+ }
+ }
+ }
+
+ switch (mEffectiveTRRMode) {
+ case nsIRequest::TRR_DISABLED_MODE:
+ AccumulateCategorical(Telemetry::LABELS_DNS_LOOKUP_ALGORITHM::nativeOnly);
+ break;
+ case nsIRequest::TRR_FIRST_MODE:
+ AccumulateCategorical(Telemetry::LABELS_DNS_LOOKUP_ALGORITHM::trrFirst);
+ break;
+ case nsIRequest::TRR_ONLY_MODE:
+ AccumulateCategorical(Telemetry::LABELS_DNS_LOOKUP_ALGORITHM::trrOnly);
+ break;
+ case nsIRequest::TRR_DEFAULT_MODE:
+ MOZ_ASSERT_UNREACHABLE("We should not have a default value here");
+ break;
+ }
+
+ if (mTRRUsed && !mTRRSuccess && mNativeSuccess && gTRRService) {
+ gTRRService->AddToBlocklist(nsCString(host), originSuffix, pb, true);
+ }
+}
+
+AddrHostRecord::DnsPriority AddrHostRecord::GetPriority(uint16_t aFlags) {
+ if (IsHighPriority(aFlags)) {
+ return AddrHostRecord::DNS_PRIORITY_HIGH;
+ }
+ if (IsMediumPriority(aFlags)) {
+ return AddrHostRecord::DNS_PRIORITY_MEDIUM;
+ }
+
+ return AddrHostRecord::DNS_PRIORITY_LOW;
+}
+
+NS_IMPL_ISUPPORTS_INHERITED(TypeHostRecord, nsHostRecord, TypeHostRecord,
+ nsIDNSTXTRecord, nsIDNSHTTPSSVCRecord)
+
+TypeHostRecord::TypeHostRecord(const nsHostKey& key)
+ : nsHostRecord(key),
+ DNSHTTPSSVCRecordBase(key.host),
+ mResultsLock("TypeHostRecord.mResultsLock"),
+ mAllRecordsExcluded(false) {}
+
+TypeHostRecord::~TypeHostRecord() { mCallbacks.clear(); }
+
+bool TypeHostRecord::HasUsableResultInternal() const {
+ return !mResults.is<Nothing>();
+}
+
+NS_IMETHODIMP TypeHostRecord::GetRecords(CopyableTArray<nsCString>& aRecords) {
+ // deep copy
+ MutexAutoLock lock(mResultsLock);
+
+ if (!mResults.is<TypeRecordTxt>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+ aRecords = mResults.as<CopyableTArray<nsCString>>();
+ return NS_OK;
+}
+
+NS_IMETHODIMP TypeHostRecord::GetRecordsAsOneString(nsACString& aRecords) {
+ // deep copy
+ MutexAutoLock lock(mResultsLock);
+
+ if (!mResults.is<TypeRecordTxt>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+ auto& results = mResults.as<CopyableTArray<nsCString>>();
+ for (uint32_t i = 0; i < results.Length(); i++) {
+ aRecords.Append(results[i]);
+ }
+ return NS_OK;
+}
+
+size_t TypeHostRecord::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) const {
+ size_t n = mallocSizeOf(this);
+
+ n += nsHostKey::SizeOfExcludingThis(mallocSizeOf);
+ n += SizeOfResolveHostCallbackListExcludingHead(mCallbacks, mallocSizeOf);
+
+ return n;
+}
+
+uint32_t TypeHostRecord::GetType() {
+ MutexAutoLock lock(mResultsLock);
+
+ return mResults.match(
+ [](TypeRecordEmpty&) {
+ MOZ_ASSERT(false, "This should never be the case");
+ return nsIDNSService::RESOLVE_TYPE_DEFAULT;
+ },
+ [](TypeRecordTxt&) { return nsIDNSService::RESOLVE_TYPE_TXT; },
+ [](TypeRecordHTTPSSVC&) { return nsIDNSService::RESOLVE_TYPE_HTTPSSVC; });
+}
+
+TypeRecordResultType TypeHostRecord::GetResults() {
+ MutexAutoLock lock(mResultsLock);
+ return mResults;
+}
+
+NS_IMETHODIMP
+TypeHostRecord::GetRecords(nsTArray<RefPtr<nsISVCBRecord>>& aRecords) {
+ MutexAutoLock lock(mResultsLock);
+ if (!mResults.is<TypeRecordHTTPSSVC>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ auto& results = mResults.as<TypeRecordHTTPSSVC>();
+
+ for (const SVCB& r : results) {
+ RefPtr<nsISVCBRecord> rec = new mozilla::net::SVCBRecord(r);
+ aRecords.AppendElement(rec);
+ }
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+TypeHostRecord::GetServiceModeRecord(bool aNoHttp2, bool aNoHttp3,
+ nsISVCBRecord** aRecord) {
+ MutexAutoLock lock(mResultsLock);
+ if (!mResults.is<TypeRecordHTTPSSVC>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ auto& results = mResults.as<TypeRecordHTTPSSVC>();
+ nsCOMPtr<nsISVCBRecord> result = GetServiceModeRecordInternal(
+ aNoHttp2, aNoHttp3, results, mAllRecordsExcluded);
+ if (!result) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ result.forget(aRecord);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+TypeHostRecord::GetAllRecordsWithEchConfig(
+ bool aNoHttp2, bool aNoHttp3, bool* aAllRecordsHaveEchConfig,
+ bool* aAllRecordsInH3ExcludedList,
+ nsTArray<RefPtr<nsISVCBRecord>>& aResult) {
+ MutexAutoLock lock(mResultsLock);
+ if (!mResults.is<TypeRecordHTTPSSVC>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ auto& records = mResults.as<TypeRecordHTTPSSVC>();
+ GetAllRecordsWithEchConfigInternal(aNoHttp2, aNoHttp3, records,
+ aAllRecordsHaveEchConfig,
+ aAllRecordsInH3ExcludedList, aResult);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+TypeHostRecord::GetHasIPAddresses(bool* aResult) {
+ NS_ENSURE_ARG(aResult);
+
+ if (!mResults.is<TypeRecordHTTPSSVC>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ auto& results = mResults.as<TypeRecordHTTPSSVC>();
+ *aResult = HasIPAddressesInternal(results);
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+TypeHostRecord::GetAllRecordsExcluded(bool* aResult) {
+ NS_ENSURE_ARG(aResult);
+
+ if (!mResults.is<TypeRecordHTTPSSVC>()) {
+ return NS_ERROR_NOT_AVAILABLE;
+ }
+
+ *aResult = mAllRecordsExcluded;
+ return NS_OK;
+}
+
+//----------------------------------------------------------------------------
+
+static const char kPrefGetTtl[] = "network.dns.get-ttl";
+static const char kPrefNativeIsLocalhost[] = "network.dns.native-is-localhost";
+static const char kPrefThreadIdleTime[] =
+ "network.dns.resolver-thread-extra-idle-time-seconds";
+static bool sGetTtlEnabled = false;
+mozilla::Atomic<bool, mozilla::Relaxed> gNativeIsLocalhost;
+
+static void DnsPrefChanged(const char* aPref, void* aSelf) {
+ MOZ_ASSERT(NS_IsMainThread(),
+ "Should be getting pref changed notification on main thread!");
+
+ MOZ_ASSERT(aSelf);
+
+ if (!strcmp(aPref, kPrefGetTtl)) {
+#ifdef DNSQUERY_AVAILABLE
+ sGetTtlEnabled = Preferences::GetBool(kPrefGetTtl);
+#endif
+ } else if (!strcmp(aPref, kPrefNativeIsLocalhost)) {
+ gNativeIsLocalhost = Preferences::GetBool(kPrefNativeIsLocalhost);
+ }
+}
+
+NS_IMPL_ISUPPORTS0(nsHostResolver)
+
+nsHostResolver::nsHostResolver(uint32_t maxCacheEntries,
+ uint32_t defaultCacheEntryLifetime,
+ uint32_t defaultGracePeriod)
+ : mMaxCacheEntries(maxCacheEntries),
+ mDefaultCacheLifetime(defaultCacheEntryLifetime),
+ mDefaultGracePeriod(defaultGracePeriod),
+ mLock("nsHostResolver.mLock"),
+ mIdleTaskCV(mLock, "nsHostResolver.mIdleTaskCV"),
+ mEvictionQSize(0),
+ mShutdown(true),
+ mNumIdleTasks(0),
+ mActiveTaskCount(0),
+ mActiveAnyThreadCount(0),
+ mPendingCount(0) {
+ mCreationTime = PR_Now();
+
+ mLongIdleTimeout = TimeDuration::FromSeconds(LongIdleTimeoutSeconds);
+ mShortIdleTimeout = TimeDuration::FromSeconds(ShortIdleTimeoutSeconds);
+}
+
+nsHostResolver::~nsHostResolver() = default;
+
+nsresult nsHostResolver::Init() {
+ MOZ_ASSERT(NS_IsMainThread());
+ if (NS_FAILED(GetAddrInfoInit())) {
+ return NS_ERROR_FAILURE;
+ }
+
+ LOG(("nsHostResolver::Init this=%p", this));
+
+ mShutdown = false;
+ mNCS = NetworkConnectivityService::GetSingleton();
+
+ // The preferences probably haven't been loaded from the disk yet, so we
+ // need to register a callback that will set up the experiment once they
+ // are. We also need to explicitly set a value for the props otherwise the
+ // callback won't be called.
+ {
+ DebugOnly<nsresult> rv = Preferences::RegisterCallbackAndCall(
+ &DnsPrefChanged, kPrefGetTtl, this);
+ NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+ "Could not register DNS TTL pref callback.");
+ rv = Preferences::RegisterCallbackAndCall(&DnsPrefChanged,
+ kPrefNativeIsLocalhost, this);
+ NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+ "Could not register DNS pref callback.");
+ }
+
+#if defined(HAVE_RES_NINIT)
+ // We want to make sure the system is using the correct resolver settings,
+ // so we force it to reload those settings whenever we startup a subsequent
+ // nsHostResolver instance. We assume that there is no reason to do this
+ // for the first nsHostResolver instance since that is usually created
+ // during application startup.
+ static int initCount = 0;
+ if (initCount++ > 0) {
+ LOG(("Calling 'res_ninit'.\n"));
+ res_ninit(&_res);
+ }
+#endif
+
+ // We can configure the threadpool to keep threads alive for a while after
+ // the last ThreadFunc task has been executed.
+ int32_t poolTimeoutSecs = Preferences::GetInt(kPrefThreadIdleTime, 60);
+ uint32_t poolTimeoutMs;
+ if (poolTimeoutSecs < 0) {
+ // This means never shut down the idle threads
+ poolTimeoutMs = UINT32_MAX;
+ } else {
+ // We clamp down the idle time between 0 and one hour.
+ poolTimeoutMs =
+ mozilla::clamped<uint32_t>(poolTimeoutSecs * 1000, 0, 3600 * 1000);
+ }
+
+ nsCOMPtr<nsIThreadPool> threadPool = new nsThreadPool();
+ MOZ_ALWAYS_SUCCEEDS(threadPool->SetThreadLimit(MAX_RESOLVER_THREADS));
+ MOZ_ALWAYS_SUCCEEDS(threadPool->SetIdleThreadLimit(MAX_RESOLVER_THREADS));
+ MOZ_ALWAYS_SUCCEEDS(threadPool->SetIdleThreadTimeout(poolTimeoutMs));
+ MOZ_ALWAYS_SUCCEEDS(
+ threadPool->SetThreadStackSize(nsIThreadManager::kThreadPoolStackSize));
+ MOZ_ALWAYS_SUCCEEDS(threadPool->SetName("DNS Resolver"_ns));
+ mResolverThreads = ToRefPtr(std::move(threadPool));
+
+ return NS_OK;
+}
+
+void nsHostResolver::ClearPendingQueue(
+ LinkedList<RefPtr<nsHostRecord>>& aPendingQ) {
+ // loop through pending queue, erroring out pending lookups.
+ if (!aPendingQ.isEmpty()) {
+ for (const RefPtr<nsHostRecord>& rec : aPendingQ) {
+ rec->Cancel();
+ if (rec->IsAddrRecord()) {
+ CompleteLookup(rec, NS_ERROR_ABORT, nullptr, rec->pb, rec->originSuffix,
+ rec->mTRRTRRSkippedReason);
+ } else {
+ mozilla::net::TypeRecordResultType empty(Nothing{});
+ CompleteLookupByType(rec, NS_ERROR_ABORT, empty, 0, rec->pb);
+ }
+ }
+ }
+}
+
+//
+// FlushCache() is what we call when the network has changed. We must not
+// trust names that were resolved before this change. They may resolve
+// differently now.
+//
+// This function removes all existing resolved host entries from the hash.
+// Names that are in the pending queues can be left there. Entries in the
+// cache that have 'Resolve' set true but not 'OnQueue' are being resolved
+// right now, so we need to mark them to get re-resolved on completion!
+
+void nsHostResolver::FlushCache(bool aTrrToo) {
+ MutexAutoLock lock(mLock);
+ mEvictionQSize = 0;
+
+ // Clear the evictionQ and remove all its corresponding entries from
+ // the cache first
+ if (!mEvictionQ.isEmpty()) {
+ for (const RefPtr<nsHostRecord>& rec : mEvictionQ) {
+ rec->Cancel();
+ mRecordDB.Remove(*static_cast<nsHostKey*>(rec));
+ }
+ mEvictionQ.clear();
+ }
+
+ // Refresh the cache entries that are resolving RIGHT now, remove the rest.
+ for (auto iter = mRecordDB.Iter(); !iter.Done(); iter.Next()) {
+ nsHostRecord* record = iter.UserData();
+ // Try to remove the record, or mark it for refresh.
+ // By-type records are from TRR. We do not need to flush those entry
+ // when the network has change, because they are not local.
+ if (record->IsAddrRecord()) {
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(record);
+ MOZ_ASSERT(addrRec);
+ if (addrRec->RemoveOrRefresh(aTrrToo)) {
+ if (record->isInList()) {
+ record->remove();
+ }
+ iter.Remove();
+ }
+ }
+ }
+}
+
+void nsHostResolver::Shutdown() {
+ LOG(("Shutting down host resolver.\n"));
+
+ {
+ DebugOnly<nsresult> rv =
+ Preferences::UnregisterCallback(&DnsPrefChanged, kPrefGetTtl, this);
+ NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+ "Could not unregister DNS TTL pref callback.");
+ }
+
+ LinkedList<RefPtr<nsHostRecord>> pendingQHigh, pendingQMed, pendingQLow,
+ evictionQ;
+
+ {
+ MutexAutoLock lock(mLock);
+
+ mShutdown = true;
+
+ // Move queues to temporary lists.
+ pendingQHigh = std::move(mHighQ);
+ pendingQMed = std::move(mMediumQ);
+ pendingQLow = std::move(mLowQ);
+ evictionQ = std::move(mEvictionQ);
+
+ mEvictionQSize = 0;
+ mPendingCount = 0;
+
+ if (mNumIdleTasks) {
+ mIdleTaskCV.NotifyAll();
+ }
+
+ for (auto iter = mRecordDB.Iter(); !iter.Done(); iter.Next()) {
+ iter.UserData()->Cancel();
+ }
+ // empty host database
+ mRecordDB.Clear();
+
+ mNCS = nullptr;
+ }
+
+ ClearPendingQueue(pendingQHigh);
+ ClearPendingQueue(pendingQMed);
+ ClearPendingQueue(pendingQLow);
+
+ if (!evictionQ.isEmpty()) {
+ for (const RefPtr<nsHostRecord>& rec : evictionQ) {
+ rec->Cancel();
+ }
+ }
+
+ pendingQHigh.clear();
+ pendingQMed.clear();
+ pendingQLow.clear();
+ evictionQ.clear();
+
+ // Shutdown the resolver threads, but with a timeout of 2 seconds (prefable).
+ // If the timeout is exceeded, any stuck threads will be leaked.
+ mResolverThreads->ShutdownWithTimeout(
+ StaticPrefs::network_dns_resolver_shutdown_timeout_ms());
+
+ {
+ mozilla::DebugOnly<nsresult> rv = GetAddrInfoShutdown();
+ NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "Failed to shutdown GetAddrInfo");
+ }
+}
+
+nsresult nsHostResolver::GetHostRecord(const nsACString& host,
+ const nsACString& aTrrServer,
+ uint16_t type, uint16_t flags,
+ uint16_t af, bool pb,
+ const nsCString& originSuffix,
+ nsHostRecord** result) {
+ MutexAutoLock lock(mLock);
+ nsHostKey key(host, aTrrServer, type, flags, af, pb, originSuffix);
+
+ RefPtr<nsHostRecord>& entry = mRecordDB.GetOrInsert(key);
+ if (!entry) {
+ entry = InitRecord(key);
+ }
+
+ RefPtr<nsHostRecord> rec = entry;
+ if (rec->IsAddrRecord()) {
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ if (addrRec->addr) {
+ return NS_ERROR_FAILURE;
+ }
+ }
+
+ if (rec->mResolving) {
+ return NS_ERROR_FAILURE;
+ }
+
+ *result = rec.forget().take();
+ return NS_OK;
+}
+
+nsHostRecord* nsHostResolver::InitRecord(const nsHostKey& key) {
+ if (IS_ADDR_TYPE(key.type)) {
+ return new AddrHostRecord(key);
+ }
+ return new TypeHostRecord(key);
+}
+
+already_AddRefed<nsHostRecord> nsHostResolver::InitLoopbackRecord(
+ const nsHostKey& key, nsresult* aRv) {
+ MOZ_ASSERT(aRv);
+ MOZ_ASSERT(IS_ADDR_TYPE(key.type));
+
+ *aRv = NS_ERROR_FAILURE;
+ RefPtr<nsHostRecord> rec = InitRecord(key);
+
+ nsTArray<NetAddr> addresses;
+ PRNetAddr prAddr;
+ memset(&prAddr, 0, sizeof(prAddr));
+ if (key.af == PR_AF_INET || key.af == PR_AF_UNSPEC) {
+ MOZ_RELEASE_ASSERT(PR_StringToNetAddr("127.0.0.1", &prAddr) == PR_SUCCESS);
+ addresses.AppendElement(NetAddr(&prAddr));
+ }
+ if (key.af == PR_AF_INET6 || key.af == PR_AF_UNSPEC) {
+ MOZ_RELEASE_ASSERT(PR_StringToNetAddr("::1", &prAddr) == PR_SUCCESS);
+ addresses.AppendElement(NetAddr(&prAddr));
+ }
+
+ RefPtr<AddrInfo> ai = new AddrInfo(rec->host, 0, std::move(addresses));
+
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MutexAutoLock lock(addrRec->addr_info_lock);
+ addrRec->addr_info = ai;
+ addrRec->SetExpiration(TimeStamp::NowLoRes(), mDefaultCacheLifetime,
+ mDefaultGracePeriod);
+ addrRec->negative = false;
+
+ *aRv = NS_OK;
+ return rec.forget();
+}
+
+nsresult nsHostResolver::ResolveHost(const nsACString& aHost,
+ const nsACString& aTrrServer,
+ uint16_t type,
+ const OriginAttributes& aOriginAttributes,
+ uint16_t flags, uint16_t af,
+ nsResolveHostCallback* aCallback) {
+ nsAutoCString host(aHost);
+ NS_ENSURE_TRUE(!host.IsEmpty(), NS_ERROR_UNEXPECTED);
+
+ nsAutoCString originSuffix;
+ aOriginAttributes.CreateSuffix(originSuffix);
+ LOG(("Resolving host [%s]<%s>%s%s type %d. [this=%p]\n", host.get(),
+ originSuffix.get(), flags & RES_BYPASS_CACHE ? " - bypassing cache" : "",
+ flags & RES_REFRESH_CACHE ? " - refresh cache" : "", type, this));
+
+ // ensure that we are working with a valid hostname before proceeding. see
+ // bug 304904 for details.
+ if (!net_IsValidHostName(host)) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+
+ // By-Type requests use only TRR. If TRR is disabled we can return
+ // immediately.
+ if (IS_OTHER_TYPE(type) && Mode() == MODE_TRROFF) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+
+ // Used to try to parse to an IP address literal.
+ PRNetAddr tempAddr;
+ // Unfortunately, PR_StringToNetAddr does not properly initialize
+ // the output buffer in the case of IPv6 input. See bug 223145.
+ memset(&tempAddr, 0, sizeof(PRNetAddr));
+
+ if (IS_OTHER_TYPE(type) &&
+ (PR_StringToNetAddr(host.get(), &tempAddr) == PR_SUCCESS)) {
+ // For by-type queries the host cannot be IP literal.
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+ memset(&tempAddr, 0, sizeof(PRNetAddr));
+
+ RefPtr<nsResolveHostCallback> callback(aCallback);
+ // if result is set inside the lock, then we need to issue the
+ // callback before returning.
+ RefPtr<nsHostRecord> result;
+ nsresult status = NS_OK, rv = NS_OK;
+ {
+ MutexAutoLock lock(mLock);
+
+ if (mShutdown) {
+ return NS_ERROR_NOT_INITIALIZED;
+ }
+
+ // check to see if there is already an entry for this |host|
+ // in the hash table. if so, then check to see if we can't
+ // just reuse the lookup result. otherwise, if there are
+ // any pending callbacks, then add to pending callbacks queue,
+ // and return. otherwise, add ourselves as first pending
+ // callback, and proceed to do the lookup.
+
+ bool excludedFromTRR = false;
+
+ if (gTRRService && gTRRService->IsExcludedFromTRR(host)) {
+ flags |= RES_DISABLE_TRR;
+ excludedFromTRR = true;
+
+ if (!aTrrServer.IsEmpty()) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+ }
+
+ nsHostKey key(host, aTrrServer, type, flags, af,
+ (aOriginAttributes.mPrivateBrowsingId > 0), originSuffix);
+
+ // Check if we have a localhost domain, if so hardcode to loopback
+ if (IS_ADDR_TYPE(type) && IsLoopbackHostname(host)) {
+ nsresult rv;
+ RefPtr<nsHostRecord> result = InitLoopbackRecord(key, &rv);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ MOZ_ASSERT(result);
+ aCallback->OnResolveHostComplete(this, result, NS_OK);
+ return NS_OK;
+ }
+
+ RefPtr<nsHostRecord>& entry = mRecordDB.GetOrInsert(key);
+ if (!entry) {
+ entry = InitRecord(key);
+ }
+
+ RefPtr<nsHostRecord> rec = entry;
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(rec, "Record should not be null");
+ MOZ_ASSERT((IS_ADDR_TYPE(type) && rec->IsAddrRecord() && addrRec) ||
+ (IS_OTHER_TYPE(type) && !rec->IsAddrRecord()));
+
+ if (excludedFromTRR) {
+ rec->RecordReason(nsHostRecord::TRR_EXCLUDED);
+ }
+
+ if (!(flags & RES_BYPASS_CACHE) &&
+ rec->HasUsableResult(TimeStamp::NowLoRes(), flags)) {
+ LOG((" Using cached record for host [%s].\n", host.get()));
+ // put reference to host record on stack...
+ result = rec;
+ if (IS_ADDR_TYPE(type)) {
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_HIT);
+ }
+
+ // For entries that are in the grace period
+ // or all cached negative entries, use the cache but start a new
+ // lookup in the background
+ ConditionallyRefreshRecord(rec, host);
+
+ if (rec->negative) {
+ LOG((" Negative cache entry for host [%s].\n", host.get()));
+ if (IS_ADDR_TYPE(type)) {
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2,
+ METHOD_NEGATIVE_HIT);
+ }
+ status = NS_ERROR_UNKNOWN_HOST;
+ }
+
+ // Check whether host is a IP address for A/AAAA queries.
+ // For by-type records we have already checked at the beginning of
+ // this function.
+ } else if (addrRec && addrRec->addr) {
+ // if the host name is an IP address literal and has been
+ // parsed, go ahead and use it.
+ LOG((" Using cached address for IP Literal [%s].\n", host.get()));
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_LITERAL);
+ result = rec;
+ } else if (addrRec &&
+ PR_StringToNetAddr(host.get(), &tempAddr) == PR_SUCCESS) {
+ // try parsing the host name as an IP address literal to short
+ // circuit full host resolution. (this is necessary on some
+ // platforms like Win9x. see bug 219376 for more details.)
+ LOG((" Host is IP Literal [%s].\n", host.get()));
+
+ // ok, just copy the result into the host record, and be
+ // done with it! ;-)
+ addrRec->addr = MakeUnique<NetAddr>();
+ PRNetAddrToNetAddr(&tempAddr, addrRec->addr.get());
+ // put reference to host record on stack...
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_LITERAL);
+ result = rec;
+
+ // Check if we have received too many requests.
+ } else if (mPendingCount >= MAX_NON_PRIORITY_REQUESTS &&
+ !IsHighPriority(flags) && !rec->mResolving) {
+ LOG(
+ (" Lookup queue full: dropping %s priority request for "
+ "host [%s].\n",
+ IsMediumPriority(flags) ? "medium" : "low", host.get()));
+ if (IS_ADDR_TYPE(type)) {
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_OVERFLOW);
+ }
+ // This is a lower priority request and we are swamped, so refuse it.
+ rv = NS_ERROR_DNS_LOOKUP_QUEUE_FULL;
+
+ // Check if the offline flag is set.
+ } else if (flags & RES_OFFLINE) {
+ LOG((" Offline request for host [%s]; ignoring.\n", host.get()));
+ rv = NS_ERROR_OFFLINE;
+
+ // We do not have a valid result till here.
+ // A/AAAA request can check for an alternative entry like AF_UNSPEC.
+ // Otherwise we need to start a new query.
+ } else if (!rec->mResolving) {
+ // If this is an IPV4 or IPV6 specific request, check if there is
+ // an AF_UNSPEC entry we can use. Otherwise, hit the resolver...
+ if (addrRec && !(flags & RES_BYPASS_CACHE) &&
+ ((af == PR_AF_INET) || (af == PR_AF_INET6))) {
+ // Check for an AF_UNSPEC entry.
+
+ const nsHostKey unspecKey(
+ host, aTrrServer, nsIDNSService::RESOLVE_TYPE_DEFAULT, flags,
+ PR_AF_UNSPEC, (aOriginAttributes.mPrivateBrowsingId > 0),
+ originSuffix);
+ RefPtr<nsHostRecord> unspecRec = mRecordDB.Get(unspecKey);
+
+ TimeStamp now = TimeStamp::NowLoRes();
+ if (unspecRec && unspecRec->HasUsableResult(now, flags)) {
+ MOZ_ASSERT(unspecRec->IsAddrRecord());
+
+ RefPtr<AddrHostRecord> addrUnspecRec = do_QueryObject(unspecRec);
+ MOZ_ASSERT(addrUnspecRec);
+ MOZ_ASSERT(addrUnspecRec->addr_info || addrUnspecRec->negative,
+ "Entry should be resolved or negative.");
+
+ LOG((" Trying AF_UNSPEC entry for host [%s] af: %s.\n", host.get(),
+ (af == PR_AF_INET) ? "AF_INET" : "AF_INET6"));
+
+ // We need to lock in case any other thread is reading
+ // addr_info.
+ MutexAutoLock lock(addrRec->addr_info_lock);
+
+ addrRec->addr_info = nullptr;
+ addrRec->addr_info_gencnt++;
+ if (unspecRec->negative) {
+ rec->negative = unspecRec->negative;
+ rec->CopyExpirationTimesAndFlagsFrom(unspecRec);
+ } else if (addrUnspecRec->addr_info) {
+ MutexAutoLock lock(addrUnspecRec->addr_info_lock);
+ if (addrUnspecRec->addr_info) {
+ // Search for any valid address in the AF_UNSPEC entry
+ // in the cache (not blocklisted and from the right
+ // family).
+ nsTArray<NetAddr> addresses;
+ for (const auto& addr : addrUnspecRec->addr_info->Addresses()) {
+ if ((af == addr.inet.family) &&
+ !addrUnspecRec->Blocklisted(&addr)) {
+ addresses.AppendElement(addr);
+ }
+ }
+ if (!addresses.IsEmpty()) {
+ addrRec->addr_info = new AddrInfo(
+ addrUnspecRec->addr_info->Hostname(),
+ addrUnspecRec->addr_info->CanonicalHostname(),
+ addrUnspecRec->addr_info->IsTRR(), std::move(addresses));
+ addrRec->addr_info_gencnt++;
+ rec->CopyExpirationTimesAndFlagsFrom(unspecRec);
+ }
+ }
+ }
+ // Now check if we have a new record.
+ if (rec->HasUsableResult(now, flags)) {
+ result = rec;
+ if (rec->negative) {
+ status = NS_ERROR_UNKNOWN_HOST;
+ }
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_HIT);
+ ConditionallyRefreshRecord(rec, host);
+ } else if (af == PR_AF_INET6) {
+ // For AF_INET6, a new lookup means another AF_UNSPEC
+ // lookup. We have already iterated through the
+ // AF_UNSPEC addresses, so we mark this record as
+ // negative.
+ LOG(
+ (" No AF_INET6 in AF_UNSPEC entry: "
+ "host [%s] unknown host.",
+ host.get()));
+ result = rec;
+ rec->negative = true;
+ status = NS_ERROR_UNKNOWN_HOST;
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2,
+ METHOD_NEGATIVE_HIT);
+ }
+ }
+ }
+
+ // If this is a by-type request or if no valid record was found
+ // in the cache or this is an AF_UNSPEC request, then start a
+ // new lookup.
+ if (!result) {
+ LOG((" No usable record in cache for host [%s] type %d.", host.get(),
+ type));
+
+ if (flags & RES_REFRESH_CACHE) {
+ rec->Invalidate();
+ }
+
+ // Add callback to the list of pending callbacks.
+ rec->mCallbacks.insertBack(callback);
+ rec->flags = flags;
+ rv = NameLookup(rec);
+ if (IS_ADDR_TYPE(type)) {
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2,
+ METHOD_NETWORK_FIRST);
+ }
+ if (NS_FAILED(rv) && callback->isInList()) {
+ callback->remove();
+ } else {
+ LOG(
+ (" DNS lookup for host [%s] blocking "
+ "pending 'getaddrinfo' or trr query: "
+ "callback [%p]",
+ host.get(), callback.get()));
+ }
+ }
+ } else {
+ LOG(
+ (" Host [%s] is being resolved. Appending callback "
+ "[%p].",
+ host.get(), callback.get()));
+
+ rec->mCallbacks.insertBack(callback);
+
+ // Only A/AAAA records are place in a queue. The queues are for
+ // the native resolver, therefore by-type request are never put
+ // into a queue.
+ if (addrRec && addrRec->onQueue()) {
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2,
+ METHOD_NETWORK_SHARED);
+
+ // Consider the case where we are on a pending queue of
+ // lower priority than the request is being made at.
+ // In that case we should upgrade to the higher queue.
+
+ if (IsHighPriority(flags) && !IsHighPriority(rec->flags)) {
+ // Move from (low|med) to high.
+ rec->remove();
+ mHighQ.insertBack(rec);
+ rec->flags = flags;
+ ConditionallyCreateThread(rec);
+ } else if (IsMediumPriority(flags) && IsLowPriority(rec->flags)) {
+ // Move from low to med.
+ rec->remove();
+ mMediumQ.insertBack(rec);
+ rec->flags = flags;
+ mIdleTaskCV.Notify();
+ }
+ }
+ }
+
+ if (result && callback->isInList()) {
+ callback->remove();
+ }
+ } // lock
+
+ if (result) {
+ callback->OnResolveHostComplete(this, result, status);
+ }
+
+ return rv;
+}
+
+void nsHostResolver::DetachCallback(
+ const nsACString& host, const nsACString& aTrrServer, uint16_t aType,
+ const OriginAttributes& aOriginAttributes, uint16_t flags, uint16_t af,
+ nsResolveHostCallback* aCallback, nsresult status) {
+ RefPtr<nsHostRecord> rec;
+ RefPtr<nsResolveHostCallback> callback(aCallback);
+
+ {
+ MutexAutoLock lock(mLock);
+
+ nsAutoCString originSuffix;
+ aOriginAttributes.CreateSuffix(originSuffix);
+
+ nsHostKey key(host, aTrrServer, aType, flags, af,
+ (aOriginAttributes.mPrivateBrowsingId > 0), originSuffix);
+ RefPtr<nsHostRecord> entry = mRecordDB.Get(key);
+ if (entry) {
+ // walk list looking for |callback|... we cannot assume
+ // that it will be there!
+
+ for (nsResolveHostCallback* c : entry->mCallbacks) {
+ if (c == callback) {
+ rec = entry;
+ c->remove();
+ break;
+ }
+ }
+ }
+ }
+
+ // complete callback with the given status code; this would only be done if
+ // the record was in the process of being resolved.
+ if (rec) {
+ callback->OnResolveHostComplete(this, rec, status);
+ }
+}
+
+nsresult nsHostResolver::ConditionallyCreateThread(nsHostRecord* rec) {
+ if (mNumIdleTasks) {
+ // wake up idle tasks to process this lookup
+ mIdleTaskCV.Notify();
+ } else if ((mActiveTaskCount < HighThreadThreshold) ||
+ (IsHighPriority(rec->flags) &&
+ mActiveTaskCount < MAX_RESOLVER_THREADS)) {
+ nsCOMPtr<nsIRunnable> event = mozilla::NewRunnableMethod(
+ "nsHostResolver::ThreadFunc", this, &nsHostResolver::ThreadFunc);
+ mActiveTaskCount++;
+ nsresult rv =
+ mResolverThreads->Dispatch(event, nsIEventTarget::DISPATCH_NORMAL);
+ if (NS_FAILED(rv)) {
+ mActiveTaskCount--;
+ }
+ } else {
+ LOG((" Unable to find a thread for looking up host [%s].\n",
+ rec->host.get()));
+ }
+ return NS_OK;
+}
+
+nsresult nsHostResolver::TrrLookup_unlocked(nsHostRecord* rec, TRR* pushedTRR) {
+ MutexAutoLock lock(mLock);
+ return TrrLookup(rec, pushedTRR);
+}
+
+void nsHostResolver::MaybeRenewHostRecord(nsHostRecord* aRec) {
+ MutexAutoLock lock(mLock);
+ MaybeRenewHostRecordLocked(aRec);
+}
+
+void nsHostResolver::MaybeRenewHostRecordLocked(nsHostRecord* aRec) {
+ mLock.AssertCurrentThreadOwns();
+ if (aRec->isInList()) {
+ // we're already on the eviction queue. This is a renewal
+ MOZ_ASSERT(mEvictionQSize);
+ AssertOnQ(aRec, mEvictionQ);
+ aRec->remove();
+ mEvictionQSize--;
+ }
+}
+
+// returns error if no TRR resolve is issued
+// it is impt this is not called while a native lookup is going on
+nsresult nsHostResolver::TrrLookup(nsHostRecord* aRec, TRR* pushedTRR) {
+ if (Mode() == MODE_TRROFF || StaticPrefs::network_dns_disabled()) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+ LOG(("TrrLookup host:%s af:%" PRId16, aRec->host.get(), aRec->af));
+
+ RefPtr<nsHostRecord> rec(aRec);
+ mLock.AssertCurrentThreadOwns();
+
+ RefPtr<AddrHostRecord> addrRec;
+ RefPtr<TypeHostRecord> typeRec;
+
+ if (rec->IsAddrRecord()) {
+ addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+ } else {
+ typeRec = do_QueryObject(rec);
+ MOZ_ASSERT(typeRec);
+ }
+
+ MOZ_ASSERT(!rec->mResolving);
+
+ auto hasConnectivity = [this]() -> bool {
+ if (!mNCS) {
+ return true;
+ }
+ nsINetworkConnectivityService::ConnectivityState ipv4 = mNCS->GetIPv4();
+ nsINetworkConnectivityService::ConnectivityState ipv6 = mNCS->GetIPv6();
+
+ if (ipv4 == nsINetworkConnectivityService::OK ||
+ ipv6 == nsINetworkConnectivityService::OK) {
+ return true;
+ }
+
+ if (ipv4 == nsINetworkConnectivityService::UNKNOWN ||
+ ipv6 == nsINetworkConnectivityService::UNKNOWN) {
+ // One of the checks hasn't completed yet. Optimistically assume we'll
+ // have network connectivity.
+ return true;
+ }
+
+ return false;
+ };
+
+ nsIRequest::TRRMode reqMode = rec->mEffectiveTRRMode;
+ if (rec->mTrrServer.IsEmpty() &&
+ (!gTRRService || !gTRRService->Enabled(reqMode))) {
+ if (NS_IsOffline()) {
+ // If we are in the NOT_CONFIRMED state _because_ we lack connectivity,
+ // then we should report that the browser is offline instead.
+ rec->RecordReason(nsHostRecord::TRR_IS_OFFLINE);
+ }
+ if (!hasConnectivity()) {
+ rec->RecordReason(nsHostRecord::TRR_NO_CONNECTIVITY);
+ } else {
+ rec->RecordReason(nsHostRecord::TRR_NOT_CONFIRMED);
+ }
+
+ LOG(("TrrLookup:: %s service not enabled\n", rec->host.get()));
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+
+ MaybeRenewHostRecordLocked(rec);
+
+ RefPtr<TRRQuery> query = new TRRQuery(this, rec);
+ nsresult rv = query->DispatchLookup(pushedTRR);
+ if (NS_FAILED(rv)) {
+ rec->RecordReason(nsHostRecord::TRR_DID_NOT_MAKE_QUERY);
+ return rv;
+ }
+
+ {
+ auto lock = rec->mTRRQuery.Lock();
+ MOZ_ASSERT(!lock.ref(), "TRR already in progress");
+ lock.ref() = query;
+ }
+
+ rec->mResolving++;
+ return NS_OK;
+}
+
+void nsHostResolver::AssertOnQ(nsHostRecord* rec,
+ LinkedList<RefPtr<nsHostRecord>>& q) {
+#ifdef DEBUG
+ MOZ_ASSERT(!q.isEmpty());
+ MOZ_ASSERT(rec->isInList());
+ for (const RefPtr<nsHostRecord>& r : q) {
+ if (rec == r) {
+ return;
+ }
+ }
+ MOZ_ASSERT(false, "Did not find element");
+#endif
+}
+
+nsresult nsHostResolver::NativeLookup(nsHostRecord* aRec) {
+ if (StaticPrefs::network_dns_disabled()) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+ LOG(("NativeLookup host:%s af:%" PRId16, aRec->host.get(), aRec->af));
+
+ // Only A/AAAA request are resolve natively.
+ MOZ_ASSERT(aRec->IsAddrRecord());
+ mLock.AssertCurrentThreadOwns();
+
+ RefPtr<nsHostRecord> rec(aRec);
+ RefPtr<AddrHostRecord> addrRec;
+ addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+
+ addrRec->mNativeStart = TimeStamp::Now();
+
+ // Add rec to one of the pending queues, possibly removing it from mEvictionQ.
+ MaybeRenewHostRecordLocked(rec);
+
+ switch (AddrHostRecord::GetPriority(rec->flags)) {
+ case AddrHostRecord::DNS_PRIORITY_HIGH:
+ mHighQ.insertBack(rec);
+ break;
+
+ case AddrHostRecord::DNS_PRIORITY_MEDIUM:
+ mMediumQ.insertBack(rec);
+ break;
+
+ case AddrHostRecord::DNS_PRIORITY_LOW:
+ mLowQ.insertBack(rec);
+ break;
+ }
+ mPendingCount++;
+
+ addrRec->StoreNative(true);
+ addrRec->StoreNativeUsed(true);
+ addrRec->mResolving++;
+
+ nsresult rv = ConditionallyCreateThread(rec);
+
+ LOG((" DNS thread counters: total=%d any-live=%d idle=%d pending=%d\n",
+ static_cast<uint32_t>(mActiveTaskCount),
+ static_cast<uint32_t>(mActiveAnyThreadCount),
+ static_cast<uint32_t>(mNumIdleTasks),
+ static_cast<uint32_t>(mPendingCount)));
+
+ return rv;
+}
+
+// static
+ResolverMode nsHostResolver::Mode() {
+ if (gTRRService) {
+ return static_cast<ResolverMode>(gTRRService->Mode());
+ }
+
+ // If we don't have a TRR service just return MODE_TRROFF so we don't make
+ // any TRR requests by mistake.
+ return MODE_TRROFF;
+}
+
+nsIRequest::TRRMode nsHostRecord::TRRMode() {
+ return nsIDNSService::GetTRRModeFromFlags(flags);
+}
+
+// static
+void nsHostResolver::ComputeEffectiveTRRMode(nsHostRecord* aRec) {
+ ResolverMode resolverMode = nsHostResolver::Mode();
+ nsIRequest::TRRMode requestMode = aRec->TRRMode();
+
+ // For domains that are excluded from TRR or when parental control is enabled,
+ // we fallback to NativeLookup. This happens even in MODE_TRRONLY. By default
+ // localhost and local are excluded (so we cover *.local hosts) See the
+ // network.trr.excluded-domains pref.
+
+ if (!gTRRService) {
+ aRec->RecordReason(nsHostRecord::TRR_NO_GSERVICE);
+ aRec->mEffectiveTRRMode = requestMode;
+ return;
+ }
+
+ if (!aRec->mTrrServer.IsEmpty()) {
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_ONLY_MODE;
+ return;
+ }
+
+ if (gTRRService->IsExcludedFromTRR(aRec->host)) {
+ aRec->RecordReason(nsHostRecord::TRR_EXCLUDED);
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_DISABLED_MODE;
+ return;
+ }
+
+ if (StaticPrefs::network_dns_skipTRR_when_parental_control_enabled() &&
+ gTRRService->ParentalControlEnabled()) {
+ aRec->RecordReason(nsHostRecord::TRR_PARENTAL_CONTROL);
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_DISABLED_MODE;
+ return;
+ }
+
+ if (resolverMode == MODE_TRROFF) {
+ aRec->RecordReason(nsHostRecord::TRR_OFF_EXPLICIT);
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_DISABLED_MODE;
+ return;
+ }
+
+ if (requestMode == nsIRequest::TRR_DISABLED_MODE) {
+ aRec->RecordReason(nsHostRecord::TRR_REQ_MODE_DISABLED);
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_DISABLED_MODE;
+ return;
+ }
+
+ if ((requestMode == nsIRequest::TRR_DEFAULT_MODE &&
+ resolverMode == MODE_NATIVEONLY)) {
+ aRec->RecordReason(nsHostRecord::TRR_MODE_NOT_ENABLED);
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_DISABLED_MODE;
+ return;
+ }
+
+ if (requestMode == nsIRequest::TRR_DEFAULT_MODE &&
+ resolverMode == MODE_TRRFIRST) {
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_FIRST_MODE;
+ return;
+ }
+
+ if (requestMode == nsIRequest::TRR_DEFAULT_MODE &&
+ resolverMode == MODE_TRRONLY) {
+ aRec->mEffectiveTRRMode = nsIRequest::TRR_ONLY_MODE;
+ return;
+ }
+
+ aRec->mEffectiveTRRMode = requestMode;
+}
+
+// Kick-off a name resolve operation, using native resolver and/or TRR
+nsresult nsHostResolver::NameLookup(nsHostRecord* rec) {
+ LOG(("NameLookup host:%s af:%" PRId16, rec->host.get(), rec->af));
+
+ if (rec->flags & RES_IP_HINT) {
+ LOG(("Skip lookup if RES_IP_HINT is set\n"));
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+
+ nsresult rv = NS_ERROR_UNKNOWN_HOST;
+ if (rec->mResolving) {
+ LOG(("NameLookup %s while already resolving\n", rec->host.get()));
+ return NS_OK;
+ }
+
+ // Make sure we reset the reason each time we attempt to do a new lookup
+ // so we don't wronly report the reason for the previous one.
+ rec->mTRRTRRSkippedReason = nsHostRecord::TRR_UNSET;
+
+ ComputeEffectiveTRRMode(rec);
+
+ if (rec->IsAddrRecord()) {
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+
+ addrRec->StoreNativeUsed(false);
+ addrRec->mTRRUsed = false;
+ addrRec->mNativeSuccess = false;
+ }
+
+ if (!rec->mTrrServer.IsEmpty()) {
+ LOG(("NameLookup: %s use trr:%s", rec->host.get(), rec->mTrrServer.get()));
+ if (rec->mEffectiveTRRMode != nsIRequest::TRR_ONLY_MODE) {
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+
+ if (rec->flags & RES_DISABLE_TRR) {
+ LOG(("TRR with server and DISABLE_TRR flag. Returning error."));
+ return NS_ERROR_UNKNOWN_HOST;
+ }
+ return TrrLookup(rec);
+ }
+
+ LOG(("NameLookup: %s effectiveTRRmode: %d flags: %X", rec->host.get(),
+ rec->mEffectiveTRRMode, rec->flags));
+
+ if (rec->flags & RES_DISABLE_TRR) {
+ rec->RecordReason(nsHostRecord::TRR_DISABLED_FLAG);
+ }
+
+ if (rec->mEffectiveTRRMode != nsIRequest::TRR_DISABLED_MODE &&
+ !((rec->flags & RES_DISABLE_TRR))) {
+ rv = TrrLookup(rec);
+ }
+
+ bool serviceNotReady = !gTRRService || !gTRRService->IsConfirmed();
+
+ if (rec->mEffectiveTRRMode == nsIRequest::TRR_DISABLED_MODE ||
+ (rec->mEffectiveTRRMode == nsIRequest::TRR_FIRST_MODE &&
+ (rec->flags & RES_DISABLE_TRR || serviceNotReady || NS_FAILED(rv)))) {
+ if (!rec->IsAddrRecord()) {
+ return rv;
+ }
+
+#ifdef DEBUG
+ // If we use this branch then the mTRRUsed flag should not be set
+ // Even if we did call TrrLookup above, the fact that it failed sync-ly
+ // means that we didn't actually succeed in opening the channel.
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec && !addrRec->mTRRUsed);
+#endif
+
+ rv = NativeLookup(rec);
+ }
+
+ return rv;
+}
+
+nsresult nsHostResolver::ConditionallyRefreshRecord(nsHostRecord* rec,
+ const nsACString& host) {
+ if ((rec->CheckExpiration(TimeStamp::NowLoRes()) != nsHostRecord::EXP_VALID ||
+ rec->negative) &&
+ !rec->mResolving) {
+ LOG((" Using %s cache entry for host [%s] but starting async renewal.",
+ rec->negative ? "negative" : "positive", host.BeginReading()));
+ NameLookup(rec);
+
+ if (rec->IsAddrRecord() && !rec->negative) {
+ // negative entries are constantly being refreshed, only
+ // track positive grace period induced renewals
+ Telemetry::Accumulate(Telemetry::DNS_LOOKUP_METHOD2, METHOD_RENEWAL);
+ }
+ }
+ return NS_OK;
+}
+
+void nsHostResolver::DeQueue(LinkedList<RefPtr<nsHostRecord>>& aQ,
+ AddrHostRecord** aResult) {
+ RefPtr<nsHostRecord> rec = aQ.popFirst();
+ mPendingCount--;
+ MOZ_ASSERT(rec->IsAddrRecord());
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+ addrRec.forget(aResult);
+}
+
+bool nsHostResolver::GetHostToLookup(AddrHostRecord** result) {
+ bool timedOut = false;
+ TimeDuration timeout;
+ TimeStamp epoch, now;
+
+ MutexAutoLock lock(mLock);
+
+ timeout = (mNumIdleTasks >= HighThreadThreshold) ? mShortIdleTimeout
+ : mLongIdleTimeout;
+ epoch = TimeStamp::Now();
+
+ while (!mShutdown) {
+ // remove next record from Q; hand over owning reference. Check high, then
+ // med, then low
+
+#define SET_GET_TTL(var, val) (var)->StoreGetTtl(sGetTtlEnabled && (val))
+
+ if (!mHighQ.isEmpty()) {
+ DeQueue(mHighQ, result);
+ SET_GET_TTL(*result, false);
+ return true;
+ }
+
+ if (mActiveAnyThreadCount < HighThreadThreshold) {
+ if (!mMediumQ.isEmpty()) {
+ DeQueue(mMediumQ, result);
+ mActiveAnyThreadCount++;
+ (*result)->StoreUsingAnyThread(true);
+ SET_GET_TTL(*result, true);
+ return true;
+ }
+
+ if (!mLowQ.isEmpty()) {
+ DeQueue(mLowQ, result);
+ mActiveAnyThreadCount++;
+ (*result)->StoreUsingAnyThread(true);
+ SET_GET_TTL(*result, true);
+ return true;
+ }
+ }
+
+ // Determining timeout is racy, so allow one cycle through checking the
+ // queues before exiting.
+ if (timedOut) {
+ break;
+ }
+
+ // wait for one or more of the following to occur:
+ // (1) the pending queue has a host record to process
+ // (2) the shutdown flag has been set
+ // (3) the thread has been idle for too long
+
+ mNumIdleTasks++;
+ mIdleTaskCV.Wait(timeout);
+ mNumIdleTasks--;
+
+ now = TimeStamp::Now();
+
+ if (now - epoch >= timeout) {
+ timedOut = true;
+ } else {
+ // It is possible that CondVar::Wait() was interrupted and returned
+ // early, in which case we will loop back and re-enter it. In that
+ // case we want to do so with the new timeout reduced to reflect
+ // time already spent waiting.
+ timeout -= now - epoch;
+ epoch = now;
+ }
+ }
+
+ // tell thread to exit...
+ return false;
+}
+
+void nsHostResolver::PrepareRecordExpirationAddrRecord(
+ AddrHostRecord* rec) const {
+ // NOTE: rec->addr_info_lock is already held by parent
+ MOZ_ASSERT(((bool)rec->addr_info) != rec->negative);
+ mLock.AssertCurrentThreadOwns();
+ if (!rec->addr_info) {
+ rec->SetExpiration(TimeStamp::NowLoRes(), NEGATIVE_RECORD_LIFETIME, 0);
+ LOG(("Caching host [%s] negative record for %u seconds.\n", rec->host.get(),
+ NEGATIVE_RECORD_LIFETIME));
+ return;
+ }
+
+ unsigned int lifetime = mDefaultCacheLifetime;
+ unsigned int grace = mDefaultGracePeriod;
+
+ unsigned int ttl = mDefaultCacheLifetime;
+ if (sGetTtlEnabled || rec->addr_info->IsTRR()) {
+ if (rec->addr_info && rec->addr_info->TTL() != AddrInfo::NO_TTL_DATA) {
+ ttl = rec->addr_info->TTL();
+ }
+ lifetime = ttl;
+ grace = 0;
+ }
+
+ rec->SetExpiration(TimeStamp::NowLoRes(), lifetime, grace);
+ LOG(("Caching host [%s] record for %u seconds (grace %d).", rec->host.get(),
+ lifetime, grace));
+}
+
+static bool different_rrset(AddrInfo* rrset1, AddrInfo* rrset2) {
+ if (!rrset1 || !rrset2) {
+ return true;
+ }
+
+ LOG(("different_rrset %s\n", rrset1->Hostname().get()));
+
+ if (rrset1->IsTRR() != rrset2->IsTRR()) {
+ return true;
+ }
+
+ if (rrset1->Addresses().Length() != rrset2->Addresses().Length()) {
+ LOG(("different_rrset true due to length change\n"));
+ return true;
+ }
+
+ nsTArray<NetAddr> orderedSet1 = rrset1->Addresses().Clone();
+ nsTArray<NetAddr> orderedSet2 = rrset2->Addresses().Clone();
+ orderedSet1.Sort();
+ orderedSet2.Sort();
+
+ bool eq = orderedSet1 == orderedSet2;
+ if (!eq) {
+ LOG(("different_rrset true due to content change\n"));
+ } else {
+ LOG(("different_rrset false\n"));
+ }
+ return !eq;
+}
+
+void nsHostResolver::AddToEvictionQ(nsHostRecord* rec) {
+ if (rec->isInList()) {
+ MOZ_DIAGNOSTIC_ASSERT(!mEvictionQ.contains(rec),
+ "Already in eviction queue");
+ MOZ_DIAGNOSTIC_ASSERT(!mHighQ.contains(rec), "Already in high queue");
+ MOZ_DIAGNOSTIC_ASSERT(!mMediumQ.contains(rec), "Already in med queue");
+ MOZ_DIAGNOSTIC_ASSERT(!mLowQ.contains(rec), "Already in low queue");
+ MOZ_DIAGNOSTIC_ASSERT(false, "Already on some other queue?");
+
+ // Bug 1678117 - it's not clear why this can happen, but let's fix it
+ // for release users.
+ rec->remove();
+ }
+ mEvictionQ.insertBack(rec);
+ if (mEvictionQSize < mMaxCacheEntries) {
+ mEvictionQSize++;
+ } else {
+ // remove first element on mEvictionQ
+ RefPtr<nsHostRecord> head = mEvictionQ.popFirst();
+ mRecordDB.Remove(*static_cast<nsHostKey*>(head.get()));
+
+ if (!head->negative) {
+ // record the age of the entry upon eviction.
+ TimeDuration age = TimeStamp::NowLoRes() - head->mValidStart;
+ if (rec->IsAddrRecord()) {
+ Telemetry::Accumulate(Telemetry::DNS_CLEANUP_AGE,
+ static_cast<uint32_t>(age.ToSeconds() / 60));
+ } else {
+ Telemetry::Accumulate(Telemetry::DNS_BY_TYPE_CLEANUP_AGE,
+ static_cast<uint32_t>(age.ToSeconds() / 60));
+ }
+ if (head->CheckExpiration(TimeStamp::Now()) !=
+ nsHostRecord::EXP_EXPIRED) {
+ if (rec->IsAddrRecord()) {
+ Telemetry::Accumulate(Telemetry::DNS_PREMATURE_EVICTION,
+ static_cast<uint32_t>(age.ToSeconds() / 60));
+ } else {
+ Telemetry::Accumulate(Telemetry::DNS_BY_TYPE_PREMATURE_EVICTION,
+ static_cast<uint32_t>(age.ToSeconds() / 60));
+ }
+ }
+ }
+ }
+}
+
+//
+// CompleteLookup() checks if the resolving should be redone and if so it
+// returns LOOKUP_RESOLVEAGAIN, but only if 'status' is not NS_ERROR_ABORT.
+nsHostResolver::LookupStatus nsHostResolver::CompleteLookup(
+ nsHostRecord* rec, nsresult status, AddrInfo* aNewRRSet, bool pb,
+ const nsACString& aOriginsuffix, nsHostRecord::TRRSkippedReason aReason) {
+ MutexAutoLock lock(mLock);
+ MOZ_ASSERT(rec);
+ MOZ_ASSERT(rec->pb == pb);
+ MOZ_ASSERT(rec->IsAddrRecord());
+
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+
+ RefPtr<AddrInfo> newRRSet(aNewRRSet);
+ MOZ_ASSERT(NS_FAILED(status) || newRRSet->Addresses().Length() > 0);
+
+ bool trrResult = newRRSet && newRRSet->IsTRR();
+ if (NS_FAILED(status)) {
+ newRRSet = nullptr;
+ }
+
+ if (addrRec->LoadResolveAgain() && (status != NS_ERROR_ABORT) && !trrResult) {
+ LOG(("nsHostResolver record %p resolve again due to flushcache\n",
+ addrRec.get()));
+ addrRec->StoreResolveAgain(false);
+ return LOOKUP_RESOLVEAGAIN;
+ }
+
+ MOZ_ASSERT(addrRec->mResolving);
+ addrRec->mResolving--;
+ LOG(("nsHostResolver::CompleteLookup %s %p %X trr=%d stillResolving=%d\n",
+ addrRec->host.get(), aNewRRSet, (unsigned int)status,
+ aNewRRSet ? aNewRRSet->IsTRR() : 0, int(addrRec->mResolving)));
+
+ if (trrResult) {
+ if (NS_FAILED(status) && status != NS_ERROR_UNKNOWN_HOST &&
+ status != NS_ERROR_DEFINITIVE_UNKNOWN_HOST) {
+ // the errors are not failed resolves, that means
+ // something else failed, consider this as *TRR not used*
+ // for actually trying to resolve the host
+ addrRec->mTRRUsed = false;
+ } else {
+ addrRec->mTRRUsed = true;
+ }
+
+ if (NS_FAILED(status)) {
+ if (aReason != nsHostRecord::TRR_UNSET) {
+ addrRec->RecordReason(aReason);
+ } else {
+ // Unknown failed reason.
+ addrRec->RecordReason(nsHostRecord::TRR_FAILED);
+ }
+ } else {
+ addrRec->mTRRSuccess++;
+ addrRec->RecordReason(nsHostRecord::TRR_OK);
+ }
+
+ if (NS_FAILED(status) &&
+ addrRec->mEffectiveTRRMode == nsIRequest::TRR_FIRST_MODE &&
+ status != NS_ERROR_DEFINITIVE_UNKNOWN_HOST) {
+ MOZ_ASSERT(!addrRec->mResolving);
+ NativeLookup(addrRec);
+ MOZ_ASSERT(addrRec->mResolving);
+ return LOOKUP_OK;
+ }
+
+ if (!addrRec->mTRRSuccess) {
+ // no TRR success
+ newRRSet = nullptr;
+ }
+
+ if (NS_FAILED(status)) {
+ // This is the error that consumers expect.
+ status = NS_ERROR_UNKNOWN_HOST;
+ }
+ } else { // native resolve completed
+ if (addrRec->LoadUsingAnyThread()) {
+ mActiveAnyThreadCount--;
+ addrRec->StoreUsingAnyThread(false);
+ }
+
+ addrRec->mNativeSuccess = static_cast<bool>(newRRSet);
+ if (addrRec->mNativeSuccess) {
+ addrRec->mNativeDuration = TimeStamp::Now() - addrRec->mNativeStart;
+ }
+ }
+
+ // This should always be cleared when a request is completed.
+ addrRec->StoreNative(false);
+
+ // update record fields. We might have a addrRec->addr_info already if a
+ // previous lookup result expired and we're reresolving it or we get
+ // a late second TRR response.
+ if (!mShutdown) {
+ MutexAutoLock lock(addrRec->addr_info_lock);
+ RefPtr<AddrInfo> old_addr_info;
+ if (different_rrset(addrRec->addr_info, newRRSet)) {
+ LOG(("nsHostResolver record %p new gencnt\n", addrRec.get()));
+ old_addr_info = addrRec->addr_info;
+ addrRec->addr_info = std::move(newRRSet);
+ addrRec->addr_info_gencnt++;
+ } else {
+ if (addrRec->addr_info && newRRSet) {
+ auto builder = addrRec->addr_info->Build();
+ builder.SetTTL(newRRSet->TTL());
+ // Update trr timings
+ builder.SetTrrFetchDuration(newRRSet->GetTrrFetchDuration());
+ builder.SetTrrFetchDurationNetworkOnly(
+ newRRSet->GetTrrFetchDurationNetworkOnly());
+
+ addrRec->addr_info = builder.Finish();
+ }
+ old_addr_info = std::move(newRRSet);
+ }
+ addrRec->negative = !addrRec->addr_info;
+ PrepareRecordExpirationAddrRecord(addrRec);
+ }
+
+ if (LOG_ENABLED()) {
+ MutexAutoLock lock(addrRec->addr_info_lock);
+ if (addrRec->addr_info) {
+ for (const auto& elem : addrRec->addr_info->Addresses()) {
+ char buf[128];
+ elem.ToStringBuffer(buf, sizeof(buf));
+ LOG(("CompleteLookup: %s has %s\n", addrRec->host.get(), buf));
+ }
+ } else {
+ LOG(("CompleteLookup: %s has NO address\n", addrRec->host.get()));
+ }
+ }
+
+ // get the list of pending callbacks for this lookup, and notify
+ // them that the lookup is complete.
+ mozilla::LinkedList<RefPtr<nsResolveHostCallback>> cbs =
+ std::move(rec->mCallbacks);
+
+ LOG(("nsHostResolver record %p calling back dns users status:%X\n",
+ addrRec.get(), int(status)));
+
+ for (nsResolveHostCallback* c = cbs.getFirst(); c;
+ c = c->removeAndGetNext()) {
+ c->OnResolveHostComplete(this, rec, status);
+ }
+
+ if (!addrRec->mResolving && !mShutdown) {
+ {
+ auto trrQuery = addrRec->mTRRQuery.Lock();
+ if (trrQuery.ref()) {
+ addrRec->mTrrDuration = trrQuery.ref()->Duration();
+ }
+ trrQuery.ref() = nullptr;
+ }
+ addrRec->ResolveComplete();
+
+ AddToEvictionQ(rec);
+ }
+
+#ifdef DNSQUERY_AVAILABLE
+ // Unless the result is from TRR, resolve again to get TTL
+ bool hasNativeResult = false;
+ {
+ MutexAutoLock lock(addrRec->addr_info_lock);
+ if (addrRec->addr_info && !addrRec->addr_info->IsTRR()) {
+ hasNativeResult = true;
+ }
+ }
+ if (hasNativeResult && !mShutdown && !addrRec->LoadGetTtl() &&
+ !rec->mResolving && sGetTtlEnabled) {
+ LOG(("Issuing second async lookup for TTL for host [%s].",
+ addrRec->host.get()));
+ addrRec->flags = (addrRec->flags & ~RES_PRIORITY_MEDIUM) | RES_PRIORITY_LOW;
+ DebugOnly<nsresult> rv = NativeLookup(rec);
+ NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+ "Could not issue second async lookup for TTL.");
+ }
+#endif
+ return LOOKUP_OK;
+}
+
+nsHostResolver::LookupStatus nsHostResolver::CompleteLookupByType(
+ nsHostRecord* rec, nsresult status,
+ mozilla::net::TypeRecordResultType& aResult, uint32_t aTtl, bool pb) {
+ MutexAutoLock lock(mLock);
+ MOZ_ASSERT(rec);
+ MOZ_ASSERT(rec->pb == pb);
+ MOZ_ASSERT(!rec->IsAddrRecord());
+
+ RefPtr<TypeHostRecord> typeRec = do_QueryObject(rec);
+ MOZ_ASSERT(typeRec);
+
+ MOZ_ASSERT(typeRec->mResolving);
+ typeRec->mResolving--;
+
+ {
+ auto lock = rec->mTRRQuery.Lock();
+ lock.ref() = nullptr;
+ }
+
+ uint32_t duration = static_cast<uint32_t>(
+ (TimeStamp::Now() - typeRec->mStart).ToMilliseconds());
+
+ if (NS_FAILED(status)) {
+ LOG(("nsHostResolver::CompleteLookupByType record %p [%s] status %x\n",
+ typeRec.get(), typeRec->host.get(), (unsigned int)status));
+ typeRec->SetExpiration(TimeStamp::NowLoRes(), NEGATIVE_RECORD_LIFETIME, 0);
+ MOZ_ASSERT(aResult.is<TypeRecordEmpty>());
+ status = NS_ERROR_UNKNOWN_HOST;
+ typeRec->negative = true;
+ Telemetry::Accumulate(Telemetry::DNS_BY_TYPE_FAILED_LOOKUP_TIME, duration);
+ } else {
+ size_t recordCount = 0;
+ if (aResult.is<TypeRecordTxt>()) {
+ recordCount = aResult.as<TypeRecordTxt>().Length();
+ } else if (aResult.is<TypeRecordHTTPSSVC>()) {
+ recordCount = aResult.as<TypeRecordHTTPSSVC>().Length();
+ }
+ LOG(
+ ("nsHostResolver::CompleteLookupByType record %p [%s], number of "
+ "records %zu\n",
+ typeRec.get(), typeRec->host.get(), recordCount));
+ MutexAutoLock typeLock(typeRec->mResultsLock);
+ typeRec->mResults = aResult;
+ typeRec->SetExpiration(TimeStamp::NowLoRes(), aTtl, mDefaultGracePeriod);
+ typeRec->negative = false;
+ Telemetry::Accumulate(Telemetry::DNS_BY_TYPE_SUCCEEDED_LOOKUP_TIME,
+ duration);
+ }
+
+ mozilla::LinkedList<RefPtr<nsResolveHostCallback>> cbs =
+ std::move(typeRec->mCallbacks);
+
+ LOG(
+ ("nsHostResolver::CompleteLookupByType record %p calling back dns "
+ "users\n",
+ typeRec.get()));
+
+ for (nsResolveHostCallback* c = cbs.getFirst(); c;
+ c = c->removeAndGetNext()) {
+ c->OnResolveHostComplete(this, rec, status);
+ }
+
+ AddToEvictionQ(rec);
+ return LOOKUP_OK;
+}
+
+void nsHostResolver::CancelAsyncRequest(
+ const nsACString& host, const nsACString& aTrrServer, uint16_t aType,
+ const OriginAttributes& aOriginAttributes, uint16_t flags, uint16_t af,
+ nsIDNSListener* aListener, nsresult status)
+
+{
+ MutexAutoLock lock(mLock);
+
+ nsAutoCString originSuffix;
+ aOriginAttributes.CreateSuffix(originSuffix);
+
+ // Lookup the host record associated with host, flags & address family
+
+ nsHostKey key(host, aTrrServer, aType, flags, af,
+ (aOriginAttributes.mPrivateBrowsingId > 0), originSuffix);
+ RefPtr<nsHostRecord> rec = mRecordDB.Get(key);
+ if (rec) {
+ nsHostRecord* recPtr = nullptr;
+
+ for (const RefPtr<nsResolveHostCallback>& c : rec->mCallbacks) {
+ if (c->EqualsAsyncListener(aListener)) {
+ c->remove();
+ recPtr = rec;
+ c->OnResolveHostComplete(this, recPtr, status);
+ break;
+ }
+ }
+
+ // If there are no more callbacks, remove the hash table entry
+ if (recPtr && recPtr->mCallbacks.isEmpty()) {
+ mRecordDB.Remove(*static_cast<nsHostKey*>(recPtr));
+ // If record is on a Queue, remove it and then deref it
+ if (recPtr->isInList()) {
+ recPtr->remove();
+ }
+ }
+ }
+}
+
+size_t nsHostResolver::SizeOfIncludingThis(MallocSizeOf mallocSizeOf) const {
+ MutexAutoLock lock(mLock);
+
+ size_t n = mallocSizeOf(this);
+
+ n += mRecordDB.ShallowSizeOfExcludingThis(mallocSizeOf);
+ for (auto iter = mRecordDB.ConstIter(); !iter.Done(); iter.Next()) {
+ auto* entry = iter.UserData();
+ n += entry->SizeOfIncludingThis(mallocSizeOf);
+ }
+
+ // The following fields aren't measured.
+ // - mHighQ, mMediumQ, mLowQ, mEvictionQ, because they just point to
+ // nsHostRecords that also pointed to by entries |mRecordDB|, and
+ // measured when |mRecordDB| is measured.
+
+ return n;
+}
+
+void nsHostResolver::ThreadFunc() {
+ LOG(("DNS lookup thread - starting execution.\n"));
+
+#if defined(RES_RETRY_ON_FAILURE)
+ nsResState rs;
+#endif
+ RefPtr<AddrHostRecord> rec;
+ RefPtr<AddrInfo> ai;
+
+ do {
+ if (!rec) {
+ RefPtr<AddrHostRecord> tmpRec;
+ if (!GetHostToLookup(getter_AddRefs(tmpRec))) {
+ break; // thread shutdown signal
+ }
+ // GetHostToLookup() returns an owning reference
+ MOZ_ASSERT(tmpRec);
+ rec.swap(tmpRec);
+ }
+
+ LOG1(("DNS lookup thread - Calling getaddrinfo for host [%s].\n",
+ rec->host.get()));
+
+ TimeStamp startTime = TimeStamp::Now();
+ bool getTtl = rec->LoadGetTtl();
+ TimeDuration inQueue = startTime - rec->mNativeStart;
+ uint32_t ms = static_cast<uint32_t>(inQueue.ToMilliseconds());
+ Telemetry::Accumulate(Telemetry::DNS_NATIVE_QUEUING, ms);
+ nsresult status =
+ GetAddrInfo(rec->host, rec->af, rec->flags, getter_AddRefs(ai), getTtl);
+#if defined(RES_RETRY_ON_FAILURE)
+ if (NS_FAILED(status) && rs.Reset()) {
+ status = GetAddrInfo(rec->host, rec->af, rec->flags, getter_AddRefs(ai),
+ getTtl);
+ }
+#endif
+
+ { // obtain lock to check shutdown and manage inter-module telemetry
+ MutexAutoLock lock(mLock);
+
+ if (!mShutdown) {
+ TimeDuration elapsed = TimeStamp::Now() - startTime;
+ uint32_t millis = static_cast<uint32_t>(elapsed.ToMilliseconds());
+
+ if (NS_SUCCEEDED(status)) {
+ Telemetry::HistogramID histogramID;
+ if (!rec->addr_info_gencnt) {
+ // Time for initial lookup.
+ histogramID = Telemetry::DNS_LOOKUP_TIME;
+ } else if (!getTtl) {
+ // Time for renewal; categorized by expiration strategy.
+ histogramID = Telemetry::DNS_RENEWAL_TIME;
+ } else {
+ // Time to get TTL; categorized by expiration strategy.
+ histogramID = Telemetry::DNS_RENEWAL_TIME_FOR_TTL;
+ }
+ Telemetry::Accumulate(histogramID, millis);
+ } else {
+ Telemetry::Accumulate(Telemetry::DNS_FAILED_LOOKUP_TIME, millis);
+ }
+ }
+ }
+
+ LOG1(("DNS lookup thread - lookup completed for host [%s]: %s.\n",
+ rec->host.get(), ai ? "success" : "failure: unknown host"));
+
+ if (LOOKUP_RESOLVEAGAIN == CompleteLookup(rec, status, ai, rec->pb,
+ rec->originSuffix,
+ rec->mTRRTRRSkippedReason)) {
+ // leave 'rec' assigned and loop to make a renewed host resolve
+ LOG(("DNS lookup thread - Re-resolving host [%s].\n", rec->host.get()));
+ } else {
+ rec = nullptr;
+ }
+ } while (true);
+
+ mActiveTaskCount--;
+ LOG(("DNS lookup thread - queue empty, task finished.\n"));
+}
+
+void nsHostResolver::SetCacheLimits(uint32_t aMaxCacheEntries,
+ uint32_t aDefaultCacheEntryLifetime,
+ uint32_t aDefaultGracePeriod) {
+ MutexAutoLock lock(mLock);
+ mMaxCacheEntries = aMaxCacheEntries;
+ mDefaultCacheLifetime = aDefaultCacheEntryLifetime;
+ mDefaultGracePeriod = aDefaultGracePeriod;
+}
+
+nsresult nsHostResolver::Create(uint32_t maxCacheEntries,
+ uint32_t defaultCacheEntryLifetime,
+ uint32_t defaultGracePeriod,
+ nsHostResolver** result) {
+ RefPtr<nsHostResolver> res = new nsHostResolver(
+ maxCacheEntries, defaultCacheEntryLifetime, defaultGracePeriod);
+
+ nsresult rv = res->Init();
+ if (NS_FAILED(rv)) {
+ return rv;
+ }
+
+ res.forget(result);
+ return NS_OK;
+}
+
+void nsHostResolver::GetDNSCacheEntries(nsTArray<DNSCacheEntries>* args) {
+ MutexAutoLock lock(mLock);
+ for (auto iter = mRecordDB.Iter(); !iter.Done(); iter.Next()) {
+ // We don't pay attention to address literals, only resolved domains.
+ // Also require a host.
+ nsHostRecord* rec = iter.UserData();
+ MOZ_ASSERT(rec, "rec should never be null here!");
+
+ if (!rec) {
+ continue;
+ }
+
+ // For now we only show A/AAAA records.
+ if (!rec->IsAddrRecord()) {
+ continue;
+ }
+
+ RefPtr<AddrHostRecord> addrRec = do_QueryObject(rec);
+ MOZ_ASSERT(addrRec);
+ if (!addrRec || !addrRec->addr_info) {
+ continue;
+ }
+
+ DNSCacheEntries info;
+ info.hostname = rec->host;
+ info.family = rec->af;
+ info.expiration =
+ (int64_t)(rec->mValidEnd - TimeStamp::NowLoRes()).ToSeconds();
+ if (info.expiration <= 0) {
+ // We only need valid DNS cache entries
+ continue;
+ }
+
+ {
+ MutexAutoLock lock(addrRec->addr_info_lock);
+ for (const auto& addr : addrRec->addr_info->Addresses()) {
+ char buf[kIPv6CStrBufSize];
+ if (addr.ToStringBuffer(buf, sizeof(buf))) {
+ info.hostaddr.AppendElement(buf);
+ }
+ }
+ info.TRR = addrRec->addr_info->IsTRR();
+ }
+
+ info.originAttributesSuffix = iter.Key().originSuffix;
+
+ args->AppendElement(std::move(info));
+ }
+}
+
+#undef LOG
+#undef LOG_ENABLED
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 20:05:59 +0000