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 "net/proxy/proxy_list.h" 6 7 #include "base/callback.h" 8 #include "base/logging.h" 9 #include "base/strings/string_tokenizer.h" 10 #include "base/time/time.h" 11 #include "base/values.h" 12 #include "net/proxy/proxy_server.h" 13 14 using base::TimeDelta; 15 using base::TimeTicks; 16 17 namespace net { 18 19 ProxyList::ProxyList() { 20 } 21 22 ProxyList::~ProxyList() { 23 } 24 25 void ProxyList::Set(const std::string& proxy_uri_list) { 26 proxies_.clear(); 27 base::StringTokenizer str_tok(proxy_uri_list, ";"); 28 while (str_tok.GetNext()) { 29 ProxyServer uri = ProxyServer::FromURI( 30 str_tok.token_begin(), str_tok.token_end(), ProxyServer::SCHEME_HTTP); 31 // Silently discard malformed inputs. 32 if (uri.is_valid()) 33 proxies_.push_back(uri); 34 } 35 } 36 37 void ProxyList::SetSingleProxyServer(const ProxyServer& proxy_server) { 38 proxies_.clear(); 39 AddProxyServer(proxy_server); 40 } 41 42 void ProxyList::AddProxyServer(const ProxyServer& proxy_server) { 43 if (proxy_server.is_valid()) 44 proxies_.push_back(proxy_server); 45 } 46 47 void ProxyList::DeprioritizeBadProxies( 48 const ProxyRetryInfoMap& proxy_retry_info) { 49 // Partition the proxy list in two: 50 // (1) the known bad proxies 51 // (2) everything else 52 std::vector<ProxyServer> good_proxies; 53 std::vector<ProxyServer> bad_proxies_to_try; 54 55 std::vector<ProxyServer>::const_iterator iter = proxies_.begin(); 56 for (; iter != proxies_.end(); ++iter) { 57 ProxyRetryInfoMap::const_iterator bad_proxy = 58 proxy_retry_info.find(iter->ToURI()); 59 if (bad_proxy != proxy_retry_info.end()) { 60 // This proxy is bad. Check if it's time to retry. 61 if (bad_proxy->second.bad_until >= TimeTicks::Now()) { 62 // still invalid. 63 if (bad_proxy->second.try_while_bad) 64 bad_proxies_to_try.push_back(*iter); 65 continue; 66 } 67 } 68 good_proxies.push_back(*iter); 69 } 70 71 // "proxies_ = good_proxies + bad_proxies" 72 proxies_.swap(good_proxies); 73 proxies_.insert(proxies_.end(), bad_proxies_to_try.begin(), 74 bad_proxies_to_try.end()); 75 } 76 77 void ProxyList::RemoveProxiesWithoutScheme(int scheme_bit_field) { 78 for (std::vector<ProxyServer>::iterator it = proxies_.begin(); 79 it != proxies_.end(); ) { 80 if (!(scheme_bit_field & it->scheme())) { 81 it = proxies_.erase(it); 82 continue; 83 } 84 ++it; 85 } 86 } 87 88 void ProxyList::Clear() { 89 proxies_.clear(); 90 } 91 92 bool ProxyList::IsEmpty() const { 93 return proxies_.empty(); 94 } 95 96 size_t ProxyList::size() const { 97 return proxies_.size(); 98 } 99 100 // Returns true if |*this| lists the same proxies as |other|. 101 bool ProxyList::Equals(const ProxyList& other) const { 102 if (size() != other.size()) 103 return false; 104 return proxies_ == other.proxies_; 105 } 106 107 const ProxyServer& ProxyList::Get() const { 108 DCHECK(!proxies_.empty()); 109 return proxies_[0]; 110 } 111 112 void ProxyList::SetFromPacString(const std::string& pac_string) { 113 base::StringTokenizer entry_tok(pac_string, ";"); 114 proxies_.clear(); 115 while (entry_tok.GetNext()) { 116 ProxyServer uri = ProxyServer::FromPacString( 117 entry_tok.token_begin(), entry_tok.token_end()); 118 // Silently discard malformed inputs. 119 if (uri.is_valid()) 120 proxies_.push_back(uri); 121 } 122 123 // If we failed to parse anything from the PAC results list, fallback to 124 // DIRECT (this basically means an error in the PAC script). 125 if (proxies_.empty()) { 126 proxies_.push_back(ProxyServer::Direct()); 127 } 128 } 129 130 std::string ProxyList::ToPacString() const { 131 std::string proxy_list; 132 std::vector<ProxyServer>::const_iterator iter = proxies_.begin(); 133 for (; iter != proxies_.end(); ++iter) { 134 if (!proxy_list.empty()) 135 proxy_list += ";"; 136 proxy_list += iter->ToPacString(); 137 } 138 return proxy_list.empty() ? std::string() : proxy_list; 139 } 140 141 base::ListValue* ProxyList::ToValue() const { 142 base::ListValue* list = new base::ListValue(); 143 for (size_t i = 0; i < proxies_.size(); ++i) 144 list->AppendString(proxies_[i].ToURI()); 145 return list; 146 } 147 148 bool ProxyList::Fallback(ProxyRetryInfoMap* proxy_retry_info, 149 int net_error, 150 const BoundNetLog& net_log) { 151 152 // TODO(eroman): It would be good if instead of removing failed proxies 153 // from the list, we simply annotated them with the error code they failed 154 // with. Of course, ProxyService::ReconsiderProxyAfterError() would need to 155 // be given this information by the network transaction. 156 // 157 // The advantage of this approach is when the network transaction 158 // fails, we could output the full list of proxies that were attempted, and 159 // why each one of those failed (as opposed to just the last failure). 160 // 161 // And also, before failing the transaction wholesale, we could go back and 162 // retry the "bad proxies" which we never tried to begin with. 163 // (RemoveBadProxies would annotate them as 'expected bad' rather then delete 164 // them from the list, so we would know what they were). 165 166 if (proxies_.empty()) { 167 NOTREACHED(); 168 return false; 169 } 170 // By default, proxies are not retried for 5 minutes. 171 UpdateRetryInfoOnFallback(proxy_retry_info, 172 TimeDelta::FromMinutes(5), 173 true, 174 ProxyServer(), 175 net_error, 176 net_log); 177 178 // Remove this proxy from our list. 179 proxies_.erase(proxies_.begin()); 180 return !proxies_.empty(); 181 } 182 183 void ProxyList::AddProxyToRetryList(ProxyRetryInfoMap* proxy_retry_info, 184 base::TimeDelta retry_delay, 185 bool try_while_bad, 186 const ProxyServer& proxy_to_retry, 187 int net_error, 188 const BoundNetLog& net_log) const { 189 // Mark this proxy as bad. 190 std::string proxy_key = proxy_to_retry.ToURI(); 191 ProxyRetryInfoMap::iterator iter = proxy_retry_info->find(proxy_key); 192 if (iter != proxy_retry_info->end()) { 193 // TODO(nsylvain): This is not the first time we get this. We should 194 // double the retry time. Bug 997660. 195 iter->second.bad_until = TimeTicks::Now() + iter->second.current_delay; 196 } else { 197 ProxyRetryInfo retry_info; 198 retry_info.current_delay = retry_delay; 199 retry_info.bad_until = TimeTicks().Now() + retry_info.current_delay; 200 retry_info.try_while_bad = try_while_bad; 201 retry_info.net_error = net_error; 202 (*proxy_retry_info)[proxy_key] = retry_info; 203 } 204 net_log.AddEvent(NetLog::TYPE_PROXY_LIST_FALLBACK, 205 NetLog::StringCallback("bad_proxy", &proxy_key)); 206 } 207 208 void ProxyList::UpdateRetryInfoOnFallback( 209 ProxyRetryInfoMap* proxy_retry_info, 210 base::TimeDelta retry_delay, 211 bool reconsider, 212 const ProxyServer& another_proxy_to_bypass, 213 int net_error, 214 const BoundNetLog& net_log) const { 215 DCHECK(retry_delay != base::TimeDelta()); 216 217 if (proxies_.empty()) { 218 NOTREACHED(); 219 return; 220 } 221 222 if (!proxies_[0].is_direct()) { 223 AddProxyToRetryList(proxy_retry_info, 224 retry_delay, 225 reconsider, 226 proxies_[0], 227 net_error, 228 net_log); 229 230 // If an additional proxy to bypass is specified, add it to the retry map 231 // as well. 232 if (another_proxy_to_bypass.is_valid()) { 233 AddProxyToRetryList(proxy_retry_info, 234 retry_delay, 235 reconsider, 236 another_proxy_to_bypass, 237 net_error, 238 net_log); 239 } 240 } 241 } 242 243 } // namespace net 244