This source file includes following definitions.
- CreateServiceWatcher
- CreateServiceResolver
- CreateLocalDomainResolver
- mdns_client_
- Start
- DiscoverNewServices
- SetActivelyRefreshServices
- ReadCachedServices
- CreateTransaction
- GetServiceType
- OnRecordUpdate
- OnCachePurged
- OnTransactionResponse
- has_srv_
- Start
- SetActiveRefresh
- OnSRVRecord
- set_has_srv
- AddService
- AddSRV
- DeferUpdate
- DeliverDeferredUpdate
- RemovePTR
- RemoveSRV
- OnNsecRecord
- ScheduleQuery
- SendQuery
- mdns_client_
- StartResolving
- CreateTxtTransaction
- CreateATransaction
- CreateSrvTransaction
- GetName
- SrvRecordTransactionResponse
- TxtRecordTransactionResponse
- ARecordTransactionResponse
- AlertCallbackIfReady
- ServiceNotFound
- MDnsStatusToRequestStatus
- RecordToMetadata
- RecordToAddress
- RecordToIPAddress
- mdns_client_
- Start
- CreateTransaction
- OnTransactionComplete
- IsSuccess
- SendResolvedAddresses
#include <utility>
#include "base/logging.h"
#include "base/memory/singleton.h"
#include "base/message_loop/message_loop_proxy.h"
#include "base/stl_util.h"
#include "chrome/utility/local_discovery/service_discovery_client_impl.h"
#include "net/dns/dns_protocol.h"
#include "net/dns/record_rdata.h"
namespace local_discovery {
namespace {
const int kLocalDomainSecondAddressTimeoutMs = 100;
const int kInitialRequeryTimeSeconds = 1;
const int kMaxRequeryTimeSeconds = 2;
}
ServiceDiscoveryClientImpl::ServiceDiscoveryClientImpl(
net::MDnsClient* mdns_client) : mdns_client_(mdns_client) {
}
ServiceDiscoveryClientImpl::~ServiceDiscoveryClientImpl() {
}
scoped_ptr<ServiceWatcher> ServiceDiscoveryClientImpl::CreateServiceWatcher(
const std::string& service_type,
const ServiceWatcher::UpdatedCallback& callback) {
return scoped_ptr<ServiceWatcher>(new ServiceWatcherImpl(
service_type, callback, mdns_client_));
}
scoped_ptr<ServiceResolver> ServiceDiscoveryClientImpl::CreateServiceResolver(
const std::string& service_name,
const ServiceResolver::ResolveCompleteCallback& callback) {
return scoped_ptr<ServiceResolver>(new ServiceResolverImpl(
service_name, callback, mdns_client_));
}
scoped_ptr<LocalDomainResolver>
ServiceDiscoveryClientImpl::CreateLocalDomainResolver(
const std::string& domain,
net::AddressFamily address_family,
const LocalDomainResolver::IPAddressCallback& callback) {
return scoped_ptr<LocalDomainResolver>(new LocalDomainResolverImpl(
domain, address_family, callback, mdns_client_));
}
ServiceWatcherImpl::ServiceWatcherImpl(
const std::string& service_type,
const ServiceWatcher::UpdatedCallback& callback,
net::MDnsClient* mdns_client)
: service_type_(service_type), callback_(callback), started_(false),
actively_refresh_services_(false), mdns_client_(mdns_client) {
}
void ServiceWatcherImpl::Start() {
DCHECK(!started_);
listener_ = mdns_client_->CreateListener(
net::dns_protocol::kTypePTR, service_type_, this);
started_ = listener_->Start();
if (started_)
ReadCachedServices();
}
ServiceWatcherImpl::~ServiceWatcherImpl() {
}
void ServiceWatcherImpl::DiscoverNewServices(bool force_update) {
DCHECK(started_);
if (force_update)
services_.clear();
SendQuery(kInitialRequeryTimeSeconds, force_update);
}
void ServiceWatcherImpl::SetActivelyRefreshServices(
bool actively_refresh_services) {
DCHECK(started_);
actively_refresh_services_ = actively_refresh_services;
for (ServiceListenersMap::iterator i = services_.begin();
i != services_.end(); i++) {
i->second->SetActiveRefresh(actively_refresh_services);
}
}
void ServiceWatcherImpl::ReadCachedServices() {
DCHECK(started_);
CreateTransaction(false , true , false ,
&transaction_cache_);
}
bool ServiceWatcherImpl::CreateTransaction(
bool network, bool cache, bool force_refresh,
scoped_ptr<net::MDnsTransaction>* transaction) {
int transaction_flags = 0;
if (network)
transaction_flags |= net::MDnsTransaction::QUERY_NETWORK;
if (cache)
transaction_flags |= net::MDnsTransaction::QUERY_CACHE;
if (transaction_flags) {
*transaction = mdns_client_->CreateTransaction(
net::dns_protocol::kTypePTR, service_type_, transaction_flags,
base::Bind(&ServiceWatcherImpl::OnTransactionResponse,
base::Unretained(this), transaction));
return (*transaction)->Start();
}
return true;
}
std::string ServiceWatcherImpl::GetServiceType() const {
return listener_->GetName();
}
void ServiceWatcherImpl::OnRecordUpdate(
net::MDnsListener::UpdateType update,
const net::RecordParsed* record) {
DCHECK(started_);
if (record->type() == net::dns_protocol::kTypePTR) {
DCHECK(record->name() == GetServiceType());
const net::PtrRecordRdata* rdata = record->rdata<net::PtrRecordRdata>();
switch (update) {
case net::MDnsListener::RECORD_ADDED:
AddService(rdata->ptrdomain());
break;
case net::MDnsListener::RECORD_CHANGED:
NOTREACHED();
break;
case net::MDnsListener::RECORD_REMOVED:
RemovePTR(rdata->ptrdomain());
break;
}
} else {
DCHECK(record->type() == net::dns_protocol::kTypeSRV ||
record->type() == net::dns_protocol::kTypeTXT);
DCHECK(services_.find(record->name()) != services_.end());
if (record->type() == net::dns_protocol::kTypeSRV) {
if (update == net::MDnsListener::RECORD_REMOVED) {
RemoveSRV(record->name());
} else if (update == net::MDnsListener::RECORD_ADDED) {
AddSRV(record->name());
}
}
if (record->type() != net::dns_protocol::kTypeSRV ||
update != net::MDnsListener::RECORD_ADDED) {
DeferUpdate(UPDATE_CHANGED, record->name());
}
}
}
void ServiceWatcherImpl::OnCachePurged() {
}
void ServiceWatcherImpl::OnTransactionResponse(
scoped_ptr<net::MDnsTransaction>* transaction,
net::MDnsTransaction::Result result,
const net::RecordParsed* record) {
DCHECK(started_);
if (result == net::MDnsTransaction::RESULT_RECORD) {
const net::PtrRecordRdata* rdata = record->rdata<net::PtrRecordRdata>();
DCHECK(rdata);
AddService(rdata->ptrdomain());
} else if (result == net::MDnsTransaction::RESULT_DONE) {
transaction->reset();
}
}
ServiceWatcherImpl::ServiceListeners::ServiceListeners(
const std::string& service_name,
ServiceWatcherImpl* watcher,
net::MDnsClient* mdns_client)
: service_name_(service_name), mdns_client_(mdns_client),
update_pending_(false), has_ptr_(true), has_srv_(false) {
srv_listener_ = mdns_client->CreateListener(
net::dns_protocol::kTypeSRV, service_name, watcher);
txt_listener_ = mdns_client->CreateListener(
net::dns_protocol::kTypeTXT, service_name, watcher);
}
ServiceWatcherImpl::ServiceListeners::~ServiceListeners() {
}
bool ServiceWatcherImpl::ServiceListeners::Start() {
if (!srv_listener_->Start())
return false;
return txt_listener_->Start();
}
void ServiceWatcherImpl::ServiceListeners::SetActiveRefresh(
bool active_refresh) {
srv_listener_->SetActiveRefresh(active_refresh);
if (active_refresh && !has_srv_) {
DCHECK(has_ptr_);
srv_transaction_ = mdns_client_->CreateTransaction(
net::dns_protocol::kTypeSRV, service_name_,
net::MDnsTransaction::SINGLE_RESULT |
net::MDnsTransaction::QUERY_CACHE | net::MDnsTransaction::QUERY_NETWORK,
base::Bind(&ServiceWatcherImpl::ServiceListeners::OnSRVRecord,
base::Unretained(this)));
srv_transaction_->Start();
} else if (!active_refresh) {
srv_transaction_.reset();
}
}
void ServiceWatcherImpl::ServiceListeners::OnSRVRecord(
net::MDnsTransaction::Result result,
const net::RecordParsed* record) {
set_has_srv(record != NULL);
}
void ServiceWatcherImpl::ServiceListeners::set_has_srv(bool has_srv) {
has_srv_ = has_srv;
srv_transaction_.reset();
}
void ServiceWatcherImpl::AddService(const std::string& service) {
DCHECK(started_);
std::pair<ServiceListenersMap::iterator, bool> found = services_.insert(
make_pair(service, linked_ptr<ServiceListeners>(NULL)));
if (found.second) {
found.first->second = linked_ptr<ServiceListeners>(
new ServiceListeners(service, this, mdns_client_));
bool success = found.first->second->Start();
found.first->second->SetActiveRefresh(actively_refresh_services_);
DeferUpdate(UPDATE_ADDED, service);
DCHECK(success);
}
found.first->second->set_has_ptr(true);
}
void ServiceWatcherImpl::AddSRV(const std::string& service) {
DCHECK(started_);
ServiceListenersMap::iterator found = services_.find(service);
if (found != services_.end()) {
found->second->set_has_srv(true);
}
}
void ServiceWatcherImpl::DeferUpdate(ServiceWatcher::UpdateType update_type,
const std::string& service_name) {
ServiceListenersMap::iterator found = services_.find(service_name);
if (found != services_.end() && !found->second->update_pending()) {
found->second->set_update_pending(true);
base::MessageLoop::current()->PostTask(
FROM_HERE,
base::Bind(&ServiceWatcherImpl::DeliverDeferredUpdate, AsWeakPtr(),
update_type, service_name));
}
}
void ServiceWatcherImpl::DeliverDeferredUpdate(
ServiceWatcher::UpdateType update_type, const std::string& service_name) {
ServiceListenersMap::iterator found = services_.find(service_name);
if (found != services_.end()) {
found->second->set_update_pending(false);
if (!callback_.is_null())
callback_.Run(update_type, service_name);
}
}
void ServiceWatcherImpl::RemovePTR(const std::string& service) {
DCHECK(started_);
ServiceListenersMap::iterator found = services_.find(service);
if (found != services_.end()) {
found->second->set_has_ptr(false);
if (!found->second->has_ptr_or_srv()) {
services_.erase(found);
if (!callback_.is_null())
callback_.Run(UPDATE_REMOVED, service);
}
}
}
void ServiceWatcherImpl::RemoveSRV(const std::string& service) {
DCHECK(started_);
ServiceListenersMap::iterator found = services_.find(service);
if (found != services_.end()) {
found->second->set_has_srv(false);
if (!found->second->has_ptr_or_srv()) {
services_.erase(found);
if (!callback_.is_null())
callback_.Run(UPDATE_REMOVED, service);
}
}
}
void ServiceWatcherImpl::OnNsecRecord(const std::string& name,
unsigned rrtype) {
}
void ServiceWatcherImpl::ScheduleQuery(int timeout_seconds) {
if (timeout_seconds <= kMaxRequeryTimeSeconds) {
base::MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&ServiceWatcherImpl::SendQuery,
AsWeakPtr(),
timeout_seconds * 2 ,
false ),
base::TimeDelta::FromSeconds(timeout_seconds));
}
}
void ServiceWatcherImpl::SendQuery(int next_timeout_seconds,
bool force_update) {
CreateTransaction(true , false , force_update,
&transaction_network_);
ScheduleQuery(next_timeout_seconds);
}
ServiceResolverImpl::ServiceResolverImpl(
const std::string& service_name,
const ResolveCompleteCallback& callback,
net::MDnsClient* mdns_client)
: service_name_(service_name), callback_(callback),
metadata_resolved_(false), address_resolved_(false),
mdns_client_(mdns_client) {
}
void ServiceResolverImpl::StartResolving() {
address_resolved_ = false;
metadata_resolved_ = false;
service_staging_ = ServiceDescription();
service_staging_.service_name = service_name_;
if (!CreateTxtTransaction() || !CreateSrvTransaction()) {
ServiceNotFound(ServiceResolver::STATUS_REQUEST_TIMEOUT);
}
}
ServiceResolverImpl::~ServiceResolverImpl() {
}
bool ServiceResolverImpl::CreateTxtTransaction() {
txt_transaction_ = mdns_client_->CreateTransaction(
net::dns_protocol::kTypeTXT, service_name_,
net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE |
net::MDnsTransaction::QUERY_NETWORK,
base::Bind(&ServiceResolverImpl::TxtRecordTransactionResponse,
AsWeakPtr()));
return txt_transaction_->Start();
}
void ServiceResolverImpl::CreateATransaction() {
a_transaction_ = mdns_client_->CreateTransaction(
net::dns_protocol::kTypeA,
service_staging_.address.host(),
net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE,
base::Bind(&ServiceResolverImpl::ARecordTransactionResponse,
AsWeakPtr()));
a_transaction_->Start();
}
bool ServiceResolverImpl::CreateSrvTransaction() {
srv_transaction_ = mdns_client_->CreateTransaction(
net::dns_protocol::kTypeSRV, service_name_,
net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE |
net::MDnsTransaction::QUERY_NETWORK,
base::Bind(&ServiceResolverImpl::SrvRecordTransactionResponse,
AsWeakPtr()));
return srv_transaction_->Start();
}
std::string ServiceResolverImpl::GetName() const {
return service_name_;
}
void ServiceResolverImpl::SrvRecordTransactionResponse(
net::MDnsTransaction::Result status, const net::RecordParsed* record) {
srv_transaction_.reset();
if (status == net::MDnsTransaction::RESULT_RECORD) {
DCHECK(record);
service_staging_.address = RecordToAddress(record);
service_staging_.last_seen = record->time_created();
CreateATransaction();
} else {
ServiceNotFound(MDnsStatusToRequestStatus(status));
}
}
void ServiceResolverImpl::TxtRecordTransactionResponse(
net::MDnsTransaction::Result status, const net::RecordParsed* record) {
txt_transaction_.reset();
if (status == net::MDnsTransaction::RESULT_RECORD) {
DCHECK(record);
service_staging_.metadata = RecordToMetadata(record);
} else {
service_staging_.metadata = std::vector<std::string>();
}
metadata_resolved_ = true;
AlertCallbackIfReady();
}
void ServiceResolverImpl::ARecordTransactionResponse(
net::MDnsTransaction::Result status, const net::RecordParsed* record) {
a_transaction_.reset();
if (status == net::MDnsTransaction::RESULT_RECORD) {
DCHECK(record);
service_staging_.ip_address = RecordToIPAddress(record);
} else {
service_staging_.ip_address = net::IPAddressNumber();
}
address_resolved_ = true;
AlertCallbackIfReady();
}
void ServiceResolverImpl::AlertCallbackIfReady() {
if (metadata_resolved_ && address_resolved_) {
txt_transaction_.reset();
srv_transaction_.reset();
a_transaction_.reset();
if (!callback_.is_null())
callback_.Run(STATUS_SUCCESS, service_staging_);
}
}
void ServiceResolverImpl::ServiceNotFound(
ServiceResolver::RequestStatus status) {
txt_transaction_.reset();
srv_transaction_.reset();
a_transaction_.reset();
if (!callback_.is_null())
callback_.Run(status, ServiceDescription());
}
ServiceResolver::RequestStatus ServiceResolverImpl::MDnsStatusToRequestStatus(
net::MDnsTransaction::Result status) const {
switch (status) {
case net::MDnsTransaction::RESULT_RECORD:
return ServiceResolver::STATUS_SUCCESS;
case net::MDnsTransaction::RESULT_NO_RESULTS:
return ServiceResolver::STATUS_REQUEST_TIMEOUT;
case net::MDnsTransaction::RESULT_NSEC:
return ServiceResolver::STATUS_KNOWN_NONEXISTENT;
case net::MDnsTransaction::RESULT_DONE:
default:
NOTREACHED();
return ServiceResolver::STATUS_REQUEST_TIMEOUT;
}
}
const std::vector<std::string>& ServiceResolverImpl::RecordToMetadata(
const net::RecordParsed* record) const {
DCHECK(record->type() == net::dns_protocol::kTypeTXT);
const net::TxtRecordRdata* txt_rdata = record->rdata<net::TxtRecordRdata>();
DCHECK(txt_rdata);
return txt_rdata->texts();
}
net::HostPortPair ServiceResolverImpl::RecordToAddress(
const net::RecordParsed* record) const {
DCHECK(record->type() == net::dns_protocol::kTypeSRV);
const net::SrvRecordRdata* srv_rdata = record->rdata<net::SrvRecordRdata>();
DCHECK(srv_rdata);
return net::HostPortPair(srv_rdata->target(), srv_rdata->port());
}
const net::IPAddressNumber& ServiceResolverImpl::RecordToIPAddress(
const net::RecordParsed* record) const {
DCHECK(record->type() == net::dns_protocol::kTypeA);
const net::ARecordRdata* a_rdata = record->rdata<net::ARecordRdata>();
DCHECK(a_rdata);
return a_rdata->address();
}
LocalDomainResolverImpl::LocalDomainResolverImpl(
const std::string& domain,
net::AddressFamily address_family,
const IPAddressCallback& callback,
net::MDnsClient* mdns_client)
: domain_(domain), address_family_(address_family), callback_(callback),
transactions_finished_(0), mdns_client_(mdns_client) {
}
LocalDomainResolverImpl::~LocalDomainResolverImpl() {
timeout_callback_.Cancel();
}
void LocalDomainResolverImpl::Start() {
if (address_family_ == net::ADDRESS_FAMILY_IPV4 ||
address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
transaction_a_ = CreateTransaction(net::dns_protocol::kTypeA);
transaction_a_->Start();
}
if (address_family_ == net::ADDRESS_FAMILY_IPV6 ||
address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
transaction_aaaa_ = CreateTransaction(net::dns_protocol::kTypeAAAA);
transaction_aaaa_->Start();
}
}
scoped_ptr<net::MDnsTransaction> LocalDomainResolverImpl::CreateTransaction(
uint16 type) {
return mdns_client_->CreateTransaction(
type, domain_, net::MDnsTransaction::SINGLE_RESULT |
net::MDnsTransaction::QUERY_CACHE |
net::MDnsTransaction::QUERY_NETWORK,
base::Bind(&LocalDomainResolverImpl::OnTransactionComplete,
base::Unretained(this)));
}
void LocalDomainResolverImpl::OnTransactionComplete(
net::MDnsTransaction::Result result, const net::RecordParsed* record) {
transactions_finished_++;
if (result == net::MDnsTransaction::RESULT_RECORD) {
if (record->type() == net::dns_protocol::kTypeA) {
const net::ARecordRdata* rdata = record->rdata<net::ARecordRdata>();
address_ipv4_ = rdata->address();
} else {
DCHECK_EQ(net::dns_protocol::kTypeAAAA, record->type());
const net::AAAARecordRdata* rdata = record->rdata<net::AAAARecordRdata>();
address_ipv6_ = rdata->address();
}
}
if (transactions_finished_ == 1 &&
address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
timeout_callback_.Reset(base::Bind(
&LocalDomainResolverImpl::SendResolvedAddresses,
base::Unretained(this)));
base::MessageLoop::current()->PostDelayedTask(
FROM_HERE,
timeout_callback_.callback(),
base::TimeDelta::FromMilliseconds(kLocalDomainSecondAddressTimeoutMs));
} else if (transactions_finished_ == 2
|| address_family_ != net::ADDRESS_FAMILY_UNSPECIFIED) {
SendResolvedAddresses();
}
}
bool LocalDomainResolverImpl::IsSuccess() {
return !address_ipv4_.empty() || !address_ipv6_.empty();
}
void LocalDomainResolverImpl::SendResolvedAddresses() {
transaction_a_.reset();
transaction_aaaa_.reset();
timeout_callback_.Cancel();
callback_.Run(IsSuccess(), address_ipv4_, address_ipv6_);
}
}