| OLD | NEW |
| (Empty) |
| 1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | |
| 2 // Use of this source code is governed by a BSD-style license that can be | |
| 3 // found in the LICENSE file. | |
| 4 | |
| 5 #include "chrome/browser/net/dns_probe_job.h" | |
| 6 | |
| 7 #include "base/compiler_specific.h" | |
| 8 #include "base/memory/scoped_ptr.h" | |
| 9 #include "base/memory/weak_ptr.h" | |
| 10 #include "base/message_loop.h" | |
| 11 #include "base/time/time.h" | |
| 12 #include "net/base/address_list.h" | |
| 13 #include "net/base/net_errors.h" | |
| 14 #include "net/base/net_log.h" | |
| 15 #include "net/dns/dns_client.h" | |
| 16 #include "net/dns/dns_protocol.h" | |
| 17 #include "net/dns/dns_response.h" | |
| 18 #include "net/dns/dns_transaction.h" | |
| 19 | |
| 20 using base::TimeDelta; | |
| 21 using net::AddressList; | |
| 22 using net::BoundNetLog; | |
| 23 using net::DnsClient; | |
| 24 using net::DnsResponse; | |
| 25 using net::DnsTransaction; | |
| 26 using net::NetLog; | |
| 27 | |
| 28 namespace chrome_browser_net { | |
| 29 | |
| 30 namespace { | |
| 31 | |
| 32 // Returns true if the given net_error indicates that we received a response | |
| 33 // from the DNS server containing an error, or false if the given net_error | |
| 34 // indicates that we never received a response. | |
| 35 bool DidReceiveDnsResponse(int net_error) { | |
| 36 switch (net_error) { | |
| 37 case net::ERR_NAME_NOT_RESOLVED: // NXDOMAIN maps to this. | |
| 38 case net::ERR_DNS_MALFORMED_RESPONSE: | |
| 39 case net::ERR_DNS_SERVER_REQUIRES_TCP: | |
| 40 case net::ERR_DNS_SERVER_FAILED: | |
| 41 case net::ERR_DNS_SORT_ERROR: // Can only happen if the server responds. | |
| 42 return true; | |
| 43 default: | |
| 44 return false; | |
| 45 } | |
| 46 } | |
| 47 | |
| 48 class DnsProbeJobImpl : public DnsProbeJob { | |
| 49 public: | |
| 50 DnsProbeJobImpl(scoped_ptr<DnsClient> dns_client, | |
| 51 const DnsProbeJob::CallbackType& callback, | |
| 52 NetLog* net_log); | |
| 53 virtual ~DnsProbeJobImpl(); | |
| 54 | |
| 55 private: | |
| 56 enum QueryResult { | |
| 57 QUERY_UNKNOWN, | |
| 58 QUERY_CORRECT, | |
| 59 QUERY_INCORRECT, | |
| 60 QUERY_DNS_ERROR, | |
| 61 QUERY_NET_ERROR, | |
| 62 }; | |
| 63 | |
| 64 void Start(); | |
| 65 | |
| 66 scoped_ptr<DnsTransaction> CreateTransaction( | |
| 67 const std::string& hostname); | |
| 68 void StartTransaction(DnsTransaction* transaction); | |
| 69 // Checks that |net_error| is OK, |response| parses, and has at least one | |
| 70 // address. | |
| 71 QueryResult EvaluateGoodResponse(int net_error, const DnsResponse* response); | |
| 72 // Checks that |net_error| is OK, |response| parses but has no addresses. | |
| 73 QueryResult EvaluateBadResponse(int net_error, const DnsResponse* response); | |
| 74 DnsProbeJob::Result EvaluateQueryResults(); | |
| 75 void OnTransactionComplete(DnsTransaction* transaction, | |
| 76 int net_error, | |
| 77 const DnsResponse* response); | |
| 78 | |
| 79 BoundNetLog bound_net_log_; | |
| 80 scoped_ptr<DnsClient> dns_client_; | |
| 81 const DnsProbeJob::CallbackType callback_; | |
| 82 scoped_ptr<DnsTransaction> good_transaction_; | |
| 83 scoped_ptr<DnsTransaction> bad_transaction_; | |
| 84 bool good_running_; | |
| 85 bool bad_running_; | |
| 86 QueryResult good_result_; | |
| 87 QueryResult bad_result_; | |
| 88 base::WeakPtrFactory<DnsProbeJobImpl> weak_factory_; | |
| 89 | |
| 90 DISALLOW_COPY_AND_ASSIGN(DnsProbeJobImpl); | |
| 91 }; | |
| 92 | |
| 93 DnsProbeJobImpl::DnsProbeJobImpl(scoped_ptr<DnsClient> dns_client, | |
| 94 const DnsProbeJob::CallbackType& callback, | |
| 95 NetLog* net_log) | |
| 96 : bound_net_log_( | |
| 97 BoundNetLog::Make(net_log, NetLog::SOURCE_DNS_PROBER)), | |
| 98 dns_client_(dns_client.Pass()), | |
| 99 callback_(callback), | |
| 100 good_running_(false), | |
| 101 bad_running_(false), | |
| 102 good_result_(QUERY_UNKNOWN), | |
| 103 bad_result_(QUERY_UNKNOWN), | |
| 104 weak_factory_(this) { | |
| 105 DCHECK(dns_client_.get()); | |
| 106 DCHECK(dns_client_->GetConfig()); | |
| 107 | |
| 108 base::MessageLoop::current()->PostTask( | |
| 109 FROM_HERE, | |
| 110 base::Bind(&DnsProbeJobImpl::Start, | |
| 111 weak_factory_.GetWeakPtr())); | |
| 112 } | |
| 113 | |
| 114 DnsProbeJobImpl::~DnsProbeJobImpl() { | |
| 115 } | |
| 116 | |
| 117 void DnsProbeJobImpl::Start() { | |
| 118 // TODO(ttuttle): Pick a good random hostname for the bad case. | |
| 119 // Consider running transactions in series? | |
| 120 good_transaction_ = CreateTransaction("google.com"); | |
| 121 bad_transaction_ = CreateTransaction("thishostname.doesnotresolve"); | |
| 122 | |
| 123 // StartTransaction may call the callback synchrononously, so set these | |
| 124 // before we call it. | |
| 125 good_running_ = true; | |
| 126 bad_running_ = true; | |
| 127 | |
| 128 // TODO(ttuttle): Log probe started. | |
| 129 | |
| 130 StartTransaction(good_transaction_.get()); | |
| 131 StartTransaction(bad_transaction_.get()); | |
| 132 } | |
| 133 | |
| 134 scoped_ptr<DnsTransaction> DnsProbeJobImpl::CreateTransaction( | |
| 135 const std::string& hostname) { | |
| 136 return dns_client_->GetTransactionFactory()->CreateTransaction( | |
| 137 hostname, | |
| 138 net::dns_protocol::kTypeA, | |
| 139 base::Bind(&DnsProbeJobImpl::OnTransactionComplete, | |
| 140 base::Unretained(this)), | |
| 141 bound_net_log_); | |
| 142 } | |
| 143 | |
| 144 void DnsProbeJobImpl::StartTransaction(DnsTransaction* transaction) { | |
| 145 int rv = transaction->Start(); | |
| 146 if (rv != net::ERR_IO_PENDING) { | |
| 147 // TODO(ttuttle): Make sure this counts as unreachable, not error. | |
| 148 OnTransactionComplete(transaction, rv, NULL); | |
| 149 } | |
| 150 | |
| 151 // TODO(ttuttle): Log transaction started. | |
| 152 } | |
| 153 | |
| 154 DnsProbeJobImpl::QueryResult DnsProbeJobImpl::EvaluateGoodResponse( | |
| 155 int net_error, | |
| 156 const DnsResponse* response) { | |
| 157 if (net_error != net::OK) | |
| 158 return DidReceiveDnsResponse(net_error) ? QUERY_DNS_ERROR : QUERY_NET_ERROR; | |
| 159 | |
| 160 AddressList addr_list; | |
| 161 TimeDelta ttl; | |
| 162 DnsResponse::Result result = response->ParseToAddressList(&addr_list, &ttl); | |
| 163 | |
| 164 if (result != DnsResponse::DNS_PARSE_OK) | |
| 165 return QUERY_DNS_ERROR; | |
| 166 | |
| 167 if (addr_list.empty()) | |
| 168 return QUERY_INCORRECT; | |
| 169 | |
| 170 return QUERY_CORRECT; | |
| 171 } | |
| 172 | |
| 173 DnsProbeJobImpl::QueryResult DnsProbeJobImpl::EvaluateBadResponse( | |
| 174 int net_error, | |
| 175 const DnsResponse* response) { | |
| 176 if (net_error == net::ERR_NAME_NOT_RESOLVED) // NXDOMAIN maps to this | |
| 177 return QUERY_CORRECT; | |
| 178 | |
| 179 if (net_error != net::OK) | |
| 180 return DidReceiveDnsResponse(net_error) ? QUERY_DNS_ERROR : QUERY_NET_ERROR; | |
| 181 | |
| 182 return QUERY_INCORRECT; | |
| 183 } | |
| 184 | |
| 185 DnsProbeJob::Result DnsProbeJobImpl::EvaluateQueryResults() { | |
| 186 if (good_result_ == QUERY_NET_ERROR || bad_result_ == QUERY_NET_ERROR) | |
| 187 return SERVERS_UNREACHABLE; | |
| 188 | |
| 189 if (good_result_ == QUERY_DNS_ERROR || bad_result_ == QUERY_DNS_ERROR) | |
| 190 return SERVERS_FAILING; | |
| 191 | |
| 192 // Ignore incorrect responses to known-bad query to avoid flagging domain | |
| 193 // helpers. | |
| 194 if (good_result_ == QUERY_INCORRECT) | |
| 195 return SERVERS_INCORRECT; | |
| 196 | |
| 197 return SERVERS_CORRECT; | |
| 198 } | |
| 199 | |
| 200 void DnsProbeJobImpl::OnTransactionComplete(DnsTransaction* transaction, | |
| 201 int net_error, | |
| 202 const DnsResponse* response) { | |
| 203 if (transaction == good_transaction_.get()) { | |
| 204 DCHECK(good_running_); | |
| 205 DCHECK_EQ(QUERY_UNKNOWN, good_result_); | |
| 206 good_result_ = EvaluateGoodResponse(net_error, response); | |
| 207 good_running_ = false; | |
| 208 } else if (transaction == bad_transaction_.get()) { | |
| 209 DCHECK(bad_running_); | |
| 210 DCHECK_EQ(QUERY_UNKNOWN, bad_result_); | |
| 211 bad_result_ = EvaluateBadResponse(net_error, response); | |
| 212 bad_running_ = false; | |
| 213 } else { | |
| 214 NOTREACHED(); | |
| 215 return; | |
| 216 } | |
| 217 | |
| 218 if (good_running_ || bad_running_) | |
| 219 return; | |
| 220 | |
| 221 callback_.Run(this, EvaluateQueryResults()); | |
| 222 | |
| 223 // TODO(ttuttle): Log probe finished. | |
| 224 } | |
| 225 | |
| 226 } // namespace | |
| 227 | |
| 228 scoped_ptr<DnsProbeJob> DnsProbeJob::CreateJob( | |
| 229 scoped_ptr<DnsClient> dns_client, | |
| 230 const CallbackType& callback, | |
| 231 NetLog* net_log) { | |
| 232 return scoped_ptr<DnsProbeJob>( | |
| 233 new DnsProbeJobImpl(dns_client.Pass(), callback, net_log)); | |
| 234 } | |
| 235 | |
| 236 } // namespace chrome_browser_net | |
| OLD | NEW |