1 // Copyright (c) 2011 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/http/http_network_layer.h" 6 7 #include "base/logging.h" 8 #include "base/string_number_conversions.h" 9 #include "base/string_split.h" 10 #include "base/string_util.h" 11 #include "net/http/http_network_session.h" 12 #include "net/http/http_network_transaction.h" 13 #include "net/spdy/spdy_framer.h" 14 #include "net/spdy/spdy_session.h" 15 #include "net/spdy/spdy_session_pool.h" 16 17 namespace net { 18 19 //----------------------------------------------------------------------------- 20 HttpNetworkLayer::HttpNetworkLayer(HttpNetworkSession* session) 21 : session_(session), 22 suspended_(false) { 23 DCHECK(session_.get()); 24 } 25 26 HttpNetworkLayer::~HttpNetworkLayer() { 27 } 28 29 //----------------------------------------------------------------------------- 30 31 // static 32 HttpTransactionFactory* HttpNetworkLayer::CreateFactory( 33 HttpNetworkSession* session) { 34 DCHECK(session); 35 36 return new HttpNetworkLayer(session); 37 } 38 39 // static 40 void HttpNetworkLayer::EnableSpdy(const std::string& mode) { 41 static const char kOff[] = "off"; 42 static const char kSSL[] = "ssl"; 43 static const char kDisableSSL[] = "no-ssl"; 44 static const char kDisablePing[] = "no-ping"; 45 static const char kExclude[] = "exclude"; // Hosts to exclude 46 static const char kDisableCompression[] = "no-compress"; 47 static const char kDisableAltProtocols[] = "no-alt-protocols"; 48 static const char kEnableVersionOne[] = "v1"; 49 static const char kForceAltProtocols[] = "force-alt-protocols"; 50 static const char kSingleDomain[] = "single-domain"; 51 52 // If flow-control is enabled, received WINDOW_UPDATE and SETTINGS 53 // messages are processed and outstanding window size is actually obeyed 54 // when sending data frames, and WINDOW_UPDATE messages are generated 55 // when data is consumed. 56 static const char kEnableFlowControl[] = "flow-control"; 57 58 // We want an A/B experiment between SPDY enabled and SPDY disabled, 59 // but only for pages where SPDY *could have been* negotiated. To do 60 // this, we use NPN, but prevent it from negotiating SPDY. If the 61 // server negotiates HTTP, rather than SPDY, today that will only happen 62 // on servers that installed NPN (and could have done SPDY). But this is 63 // a bit of a hack, as this correlation between NPN and SPDY is not 64 // really guaranteed. 65 static const char kEnableNPN[] = "npn"; 66 static const char kEnableNpnHttpOnly[] = "npn-http"; 67 68 // Except for the first element, the order is irrelevant. First element 69 // specifies the fallback in case nothing matches 70 // (SSLClientSocket::kNextProtoNoOverlap). Otherwise, the SSL library 71 // will choose the first overlapping protocol in the server's list, since 72 // it presumedly has a better understanding of which protocol we should 73 // use, therefore the rest of the ordering here is not important. 74 static const char kNpnProtosFull[] = "\x08http/1.1\x06spdy/2"; 75 // This is a temporary hack to pretend we support version 1. 76 static const char kNpnProtosFullV1[] = "\x08http/1.1\x06spdy/1"; 77 // No spdy specified. 78 static const char kNpnProtosHttpOnly[] = "\x08http/1.1\x07http1.1"; 79 80 std::vector<std::string> spdy_options; 81 base::SplitString(mode, ',', &spdy_options); 82 83 bool use_alt_protocols = true; 84 85 for (std::vector<std::string>::iterator it = spdy_options.begin(); 86 it != spdy_options.end(); ++it) { 87 const std::string& element = *it; 88 std::vector<std::string> name_value; 89 base::SplitString(element, '=', &name_value); 90 const std::string& option = name_value[0]; 91 const std::string value = name_value.size() > 1 ? name_value[1] : ""; 92 93 if (option == kOff) { 94 HttpStreamFactory::set_spdy_enabled(false); 95 } else if (option == kDisableSSL) { 96 SpdySession::SetSSLMode(false); // Disable SSL 97 HttpStreamFactory::set_force_spdy_over_ssl(false); 98 HttpStreamFactory::set_force_spdy_always(true); 99 } else if (option == kSSL) { 100 HttpStreamFactory::set_force_spdy_over_ssl(true); 101 HttpStreamFactory::set_force_spdy_always(true); 102 } else if (option == kDisablePing) { 103 SpdySession::set_enable_ping_based_connection_checking(false); 104 } else if (option == kExclude) { 105 HttpStreamFactory::add_forced_spdy_exclusion(value); 106 } else if (option == kDisableCompression) { 107 spdy::SpdyFramer::set_enable_compression_default(false); 108 } else if (option == kEnableNPN) { 109 HttpStreamFactory::set_use_alternate_protocols(use_alt_protocols); 110 HttpStreamFactory::set_next_protos(kNpnProtosFull); 111 } else if (option == kEnableNpnHttpOnly) { 112 // Avoid alternate protocol in this case. Otherwise, browser will try SSL 113 // and then fallback to http. This introduces extra load. 114 HttpStreamFactory::set_use_alternate_protocols(false); 115 HttpStreamFactory::set_next_protos(kNpnProtosHttpOnly); 116 } else if (option == kEnableVersionOne) { 117 spdy::SpdyFramer::set_protocol_version(1); 118 HttpStreamFactory::set_next_protos(kNpnProtosFullV1); 119 } else if (option == kDisableAltProtocols) { 120 use_alt_protocols = false; 121 HttpStreamFactory::set_use_alternate_protocols(false); 122 } else if (option == kEnableFlowControl) { 123 SpdySession::set_flow_control(true); 124 } else if (option == kForceAltProtocols) { 125 HttpAlternateProtocols::PortProtocolPair pair; 126 pair.port = 443; 127 pair.protocol = HttpAlternateProtocols::NPN_SPDY_2; 128 HttpAlternateProtocols::ForceAlternateProtocol(pair); 129 } else if (option == kSingleDomain) { 130 SpdySessionPool::ForceSingleDomain(); 131 LOG(ERROR) << "FORCING SINGLE DOMAIN"; 132 } else if (option.empty() && it == spdy_options.begin()) { 133 continue; 134 } else { 135 LOG(DFATAL) << "Unrecognized spdy option: " << option; 136 } 137 } 138 } 139 140 //----------------------------------------------------------------------------- 141 142 int HttpNetworkLayer::CreateTransaction(scoped_ptr<HttpTransaction>* trans) { 143 if (suspended_) 144 return ERR_NETWORK_IO_SUSPENDED; 145 146 trans->reset(new HttpNetworkTransaction(GetSession())); 147 return OK; 148 } 149 150 HttpCache* HttpNetworkLayer::GetCache() { 151 return NULL; 152 } 153 154 HttpNetworkSession* HttpNetworkLayer::GetSession() { 155 return session_; 156 } 157 158 void HttpNetworkLayer::Suspend(bool suspend) { 159 suspended_ = suspend; 160 161 if (suspend && session_) 162 session_->CloseIdleConnections(); 163 } 164 165 } // namespace net 166