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/* 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
#include "TRRQuery.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/Telemetry.h"
#include "nsQueryObject.h"
#include "TRR.h"
#include "TRRService.h"
// Put DNSLogging.h at the end to avoid LOG being overwritten by other headers.
#include "DNSLogging.h"
namespace mozilla {
namespace net {
static already_AddRefed<AddrInfo> merge_rrset(AddrInfo* rrto,
AddrInfo* rrfrom) {
MOZ_ASSERT(rrto && rrfrom);
// Each of the arguments are all-IPv4 or all-IPv6 hence judging
// by the first element. This is true only for TRR resolutions.
bool isIPv6 = rrfrom->Addresses().Length() > 0 &&
rrfrom->Addresses()[0].raw.family == PR_AF_INET6;
nsTArray<NetAddr> addresses;
if (isIPv6) {
addresses = rrfrom->Addresses().Clone();
addresses.AppendElements(rrto->Addresses());
} else {
addresses = rrto->Addresses().Clone();
addresses.AppendElements(rrfrom->Addresses());
}
auto builder = rrto->Build();
builder.SetAddresses(std::move(addresses));
return builder.Finish();
}
void TRRQuery::Cancel(nsresult aStatus) {
MutexAutoLock trrlock(mTrrLock);
if (mTrrA) {
mTrrA->Cancel(aStatus);
}
if (mTrrAAAA) {
mTrrAAAA->Cancel(aStatus);
}
if (mTrrByType) {
mTrrByType->Cancel(aStatus);
}
}
void TRRQuery::MarkSendingTRR(TRR* trr, enum TrrType rectype, MutexAutoLock&) {
if (rectype == TRRTYPE_A) {
MOZ_ASSERT(!mTrrA);
mTrrA = trr;
mTrrAUsed = STARTED;
} else if (rectype == TRRTYPE_AAAA) {
MOZ_ASSERT(!mTrrAAAA);
mTrrAAAA = trr;
mTrrAAAAUsed = STARTED;
} else {
LOG(("TrrLookup called with bad type set: %d\n", rectype));
MOZ_ASSERT(0);
}
}
void TRRQuery::PrepareQuery(enum TrrType aRecType,
nsTArray<RefPtr<TRR>>& aRequestsToSend) {
LOG(("TRR Resolve %s type %d\n", mRecord->host.get(), (int)aRecType));
RefPtr<TRR> trr = new TRR(this, mRecord, aRecType);
{
MutexAutoLock trrlock(mTrrLock);
MarkSendingTRR(trr, aRecType, trrlock);
aRequestsToSend.AppendElement(trr);
}
}
bool TRRQuery::SendQueries(nsTArray<RefPtr<TRR>>& aRequestsToSend) {
bool madeQuery = false;
mTRRRequestCounter = aRequestsToSend.Length();
for (const auto& request : aRequestsToSend) {
if (NS_SUCCEEDED(TRRService::Get()->DispatchTRRRequest(request))) {
madeQuery = true;
} else {
mTRRRequestCounter--;
MutexAutoLock trrlock(mTrrLock);
if (request == mTrrA) {
mTrrA = nullptr;
mTrrAUsed = INIT;
}
if (request == mTrrAAAA) {
mTrrAAAA = nullptr;
mTrrAAAAUsed = INIT;
}
}
}
aRequestsToSend.Clear();
return madeQuery;
}
nsresult TRRQuery::DispatchLookup(TRR* pushedTRR) {
mTrrStart = TimeStamp::Now();
if (!mRecord->IsAddrRecord()) {
return DispatchByTypeLookup(pushedTRR);
}
RefPtr<AddrHostRecord> addrRec = do_QueryObject(mRecord);
MOZ_ASSERT(addrRec);
if (!addrRec) {
return NS_ERROR_UNEXPECTED;
}
mTrrAUsed = INIT;
mTrrAAAAUsed = INIT;
// Always issue both A and AAAA.
// When both are complete we filter out the unneeded results.
enum TrrType rectype = (mRecord->af == AF_INET6) ? TRRTYPE_AAAA : TRRTYPE_A;
if (pushedTRR) {
MutexAutoLock trrlock(mTrrLock);
rectype = pushedTRR->Type();
MarkSendingTRR(pushedTRR, rectype, trrlock);
return NS_OK;
}
// Need to dispatch TRR requests after |mTrrA| and |mTrrAAAA| are set
// properly so as to avoid the race when CompleteLookup() is called at the
// same time.
nsTArray<RefPtr<TRR>> requestsToSend;
if ((mRecord->af == AF_UNSPEC || mRecord->af == AF_INET6) &&
!StaticPrefs::network_dns_disableIPv6()) {
PrepareQuery(TRRTYPE_AAAA, requestsToSend);
}
if (mRecord->af == AF_UNSPEC || mRecord->af == AF_INET) {
PrepareQuery(TRRTYPE_A, requestsToSend);
}
if (SendQueries(requestsToSend)) {
return NS_OK;
}
return NS_ERROR_UNKNOWN_HOST;
}
nsresult TRRQuery::DispatchByTypeLookup(TRR* pushedTRR) {
RefPtr<TypeHostRecord> typeRec = do_QueryObject(mRecord);
MOZ_ASSERT(typeRec);
if (!typeRec) {
return NS_ERROR_UNEXPECTED;
}
enum TrrType rectype;
// XXX this could use a more extensible approach.
if (mRecord->type == nsIDNSService::RESOLVE_TYPE_TXT) {
rectype = TRRTYPE_TXT;
} else if (mRecord->type == nsIDNSService::RESOLVE_TYPE_HTTPSSVC) {
rectype = TRRTYPE_HTTPSSVC;
} else if (pushedTRR) {
rectype = pushedTRR->Type();
} else {
MOZ_ASSERT(false, "Not an expected request type");
return NS_ERROR_UNKNOWN_HOST;
}
LOG(("TRR Resolve %s type %d\n", typeRec->host.get(), (int)rectype));
RefPtr<TRR> trr = pushedTRR ? pushedTRR : new TRR(this, mRecord, rectype);
if (pushedTRR || NS_SUCCEEDED(TRRService::Get()->DispatchTRRRequest(trr))) {
MutexAutoLock trrlock(mTrrLock);
MOZ_ASSERT(!mTrrByType);
mTrrByType = trr;
return NS_OK;
}
return NS_ERROR_UNKNOWN_HOST;
}
AHostResolver::LookupStatus TRRQuery::CompleteLookup(
nsHostRecord* rec, nsresult status, AddrInfo* aNewRRSet, bool pb,
const nsACString& aOriginsuffix, nsHostRecord::TRRSkippedReason aReason,
TRR* aTRRRequest) {
if (rec != mRecord) {
LOG(("TRRQuery::CompleteLookup - Pushed record. Go to resolver"));
return mHostResolver->CompleteLookup(rec, status, aNewRRSet, pb,
aOriginsuffix, aReason, aTRRRequest);
}
LOG(("TRRQuery::CompleteLookup > host: %s", rec->host.get()));
RefPtr<AddrInfo> newRRSet(aNewRRSet);
DNSResolverType resolverType = newRRSet->ResolverType();
{
MutexAutoLock trrlock(mTrrLock);
if (newRRSet->TRRType() == TRRTYPE_A) {
MOZ_ASSERT(mTrrA);
mTRRAFailReason = aReason;
mTrrA = nullptr;
mTrrAUsed = NS_SUCCEEDED(status) ? OK : FAILED;
MOZ_ASSERT(!mAddrInfoA);
mAddrInfoA = newRRSet;
mAResult = status;
LOG(("A query status: 0x%x", static_cast<uint32_t>(status)));
} else if (newRRSet->TRRType() == TRRTYPE_AAAA) {
MOZ_ASSERT(mTrrAAAA);
mTRRAAAAFailReason = aReason;
mTrrAAAA = nullptr;
mTrrAAAAUsed = NS_SUCCEEDED(status) ? OK : FAILED;
MOZ_ASSERT(!mAddrInfoAAAA);
mAddrInfoAAAA = newRRSet;
mAAAAResult = status;
LOG(("AAAA query status: 0x%x", static_cast<uint32_t>(status)));
} else {
MOZ_ASSERT(0);
}
}
if (NS_SUCCEEDED(status)) {
mTRRSuccess++;
if (mTRRSuccess == 1) {
// Store the duration on first succesful TRR response. We
// don't know that there will be a second response nor can we
// tell which of two has useful data.
mTrrDuration = TimeStamp::Now() - mTrrStart;
}
}
bool pendingRequest = false;
if (mTRRRequestCounter) {
mTRRRequestCounter--;
pendingRequest = (mTRRRequestCounter != 0);
} else {
MOZ_DIAGNOSTIC_ASSERT(false, "Request counter is messed up");
}
if (pendingRequest) { // There are other outstanding requests
LOG(("CompleteLookup: waiting for all responses!\n"));
return LOOKUP_OK;
}
if (mRecord->af == AF_UNSPEC) {
// merge successful records
if (mTrrAUsed == OK) {
LOG(("Have A response"));
newRRSet = mAddrInfoA;
status = mAResult;
if (mTrrAAAAUsed == OK) {
LOG(("Merging A and AAAA responses"));
newRRSet = merge_rrset(newRRSet, mAddrInfoAAAA);
}
} else {
newRRSet = mAddrInfoAAAA;
status = mAAAAResult;
}
if (NS_FAILED(status) && (mAAAAResult == NS_ERROR_DEFINITIVE_UNKNOWN_HOST ||
mAResult == NS_ERROR_DEFINITIVE_UNKNOWN_HOST)) {
status = NS_ERROR_DEFINITIVE_UNKNOWN_HOST;
}
} else {
// If this is a failed AAAA request, but the server only has a A record,
// then we should not fallback to Do53. Instead we also send a A request
// and return NS_ERROR_DEFINITIVE_UNKNOWN_HOST if that succeeds.
if (NS_FAILED(status) && status != NS_ERROR_DEFINITIVE_UNKNOWN_HOST &&
(mTrrAUsed == INIT || mTrrAAAAUsed == INIT)) {
if (newRRSet->TRRType() == TRRTYPE_A) {
LOG(("A lookup failed. Checking if AAAA record exists"));
nsTArray<RefPtr<TRR>> requestsToSend;
PrepareQuery(TRRTYPE_AAAA, requestsToSend);
if (SendQueries(requestsToSend)) {
LOG(("Sent AAAA request"));
return LOOKUP_OK;
}
} else if (newRRSet->TRRType() == TRRTYPE_AAAA) {
LOG(("AAAA lookup failed. Checking if A record exists"));
nsTArray<RefPtr<TRR>> requestsToSend;
PrepareQuery(TRRTYPE_A, requestsToSend);
if (SendQueries(requestsToSend)) {
LOG(("Sent A request"));
return LOOKUP_OK;
}
} else {
MOZ_ASSERT(false, "Unexpected family");
}
}
bool otherSucceeded =
mRecord->af == AF_INET6 ? mTrrAUsed == OK : mTrrAAAAUsed == OK;
LOG(("TRRQuery::CompleteLookup other request succeeded"));
if (mRecord->af == AF_INET) {
// return only A record
newRRSet = mAddrInfoA;
status = mAResult;
if (NS_FAILED(status) &&
(otherSucceeded || mAAAAResult == NS_ERROR_DEFINITIVE_UNKNOWN_HOST)) {
LOG(("status set to NS_ERROR_DEFINITIVE_UNKNOWN_HOST"));
status = NS_ERROR_DEFINITIVE_UNKNOWN_HOST;
}
} else if (mRecord->af == AF_INET6) {
// return only AAAA record
newRRSet = mAddrInfoAAAA;
status = mAAAAResult;
if (NS_FAILED(status) &&
(otherSucceeded || mAResult == NS_ERROR_DEFINITIVE_UNKNOWN_HOST)) {
LOG(("status set to NS_ERROR_DEFINITIVE_UNKNOWN_HOST"));
status = NS_ERROR_DEFINITIVE_UNKNOWN_HOST;
}
} else {
MOZ_ASSERT(false, "Unexpected AF");
return LOOKUP_OK;
}
// If this record failed, but there is a record for the other AF
// we prevent fallback to the native resolver.
}
if (mTRRSuccess && mHostResolver->GetNCS() &&
(mHostResolver->GetNCS()->GetNAT64() ==
nsINetworkConnectivityService::OK) &&
newRRSet) {
newRRSet = mHostResolver->GetNCS()->MapNAT64IPs(newRRSet);
}
if (resolverType == DNSResolverType::TRR) {
if (mTrrAUsed == OK) {
AccumulateCategoricalKeyed(
TRRService::ProviderKey(),
Telemetry::LABELS_DNS_LOOKUP_DISPOSITION3::trrAOK);
} else if (mTrrAUsed == FAILED) {
AccumulateCategoricalKeyed(
TRRService::ProviderKey(),
Telemetry::LABELS_DNS_LOOKUP_DISPOSITION3::trrAFail);
}
if (mTrrAAAAUsed == OK) {
AccumulateCategoricalKeyed(
TRRService::ProviderKey(),
Telemetry::LABELS_DNS_LOOKUP_DISPOSITION3::trrAAAAOK);
} else if (mTrrAAAAUsed == FAILED) {
AccumulateCategoricalKeyed(
TRRService::ProviderKey(),
Telemetry::LABELS_DNS_LOOKUP_DISPOSITION3::trrAAAAFail);
}
}
mAddrInfoAAAA = nullptr;
mAddrInfoA = nullptr;
MOZ_DIAGNOSTIC_ASSERT(!mCalledCompleteLookup,
"must not call CompleteLookup more than once");
mCalledCompleteLookup = true;
return mHostResolver->CompleteLookup(rec, status, newRRSet, pb, aOriginsuffix,
aReason, aTRRRequest);
}
AHostResolver::LookupStatus TRRQuery::CompleteLookupByType(
nsHostRecord* rec, nsresult status,
mozilla::net::TypeRecordResultType& aResult,
mozilla::net::TRRSkippedReason aReason, uint32_t aTtl, bool pb) {
if (rec != mRecord) {
LOG(("TRRQuery::CompleteLookup - Pushed record. Go to resolver"));
return mHostResolver->CompleteLookupByType(rec, status, aResult, aReason,
aTtl, pb);
}
{
MutexAutoLock trrlock(mTrrLock);
mTrrByType = nullptr;
}
// Unlike the address record, we store the duration regardless of the status.
mTrrDuration = TimeStamp::Now() - mTrrStart;
MOZ_DIAGNOSTIC_ASSERT(!mCalledCompleteLookup,
"must not call CompleteLookup more than once");
mCalledCompleteLookup = true;
return mHostResolver->CompleteLookupByType(rec, status, aResult, aReason,
aTtl, pb);
}
} // namespace net
} // namespace mozilla