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// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/http/http_network_layer.h"
#include "base/logging.h"
#include "base/string_number_conversions.h"
#include "base/string_split.h"
#include "base/string_util.h"
#include "net/http/http_network_session.h"
#include "net/http/http_network_transaction.h"
#include "net/spdy/spdy_framer.h"
#include "net/spdy/spdy_session.h"
#include "net/spdy/spdy_session_pool.h"
namespace net {
//-----------------------------------------------------------------------------
HttpNetworkLayer::HttpNetworkLayer(HttpNetworkSession* session)
: session_(session),
suspended_(false) {
DCHECK(session_.get());
}
HttpNetworkLayer::~HttpNetworkLayer() {
}
//-----------------------------------------------------------------------------
// static
HttpTransactionFactory* HttpNetworkLayer::CreateFactory(
HttpNetworkSession* session) {
DCHECK(session);
return new HttpNetworkLayer(session);
}
// static
void HttpNetworkLayer::EnableSpdy(const std::string& mode) {
static const char kOff[] = "off";
static const char kSSL[] = "ssl";
static const char kDisableSSL[] = "no-ssl";
static const char kDisablePing[] = "no-ping";
static const char kExclude[] = "exclude"; // Hosts to exclude
static const char kDisableCompression[] = "no-compress";
static const char kDisableAltProtocols[] = "no-alt-protocols";
static const char kEnableVersionOne[] = "v1";
static const char kForceAltProtocols[] = "force-alt-protocols";
static const char kSingleDomain[] = "single-domain";
// If flow-control is enabled, received WINDOW_UPDATE and SETTINGS
// messages are processed and outstanding window size is actually obeyed
// when sending data frames, and WINDOW_UPDATE messages are generated
// when data is consumed.
static const char kEnableFlowControl[] = "flow-control";
// We want an A/B experiment between SPDY enabled and SPDY disabled,
// but only for pages where SPDY *could have been* negotiated. To do
// this, we use NPN, but prevent it from negotiating SPDY. If the
// server negotiates HTTP, rather than SPDY, today that will only happen
// on servers that installed NPN (and could have done SPDY). But this is
// a bit of a hack, as this correlation between NPN and SPDY is not
// really guaranteed.
static const char kEnableNPN[] = "npn";
static const char kEnableNpnHttpOnly[] = "npn-http";
// Except for the first element, the order is irrelevant. First element
// specifies the fallback in case nothing matches
// (SSLClientSocket::kNextProtoNoOverlap). Otherwise, the SSL library
// will choose the first overlapping protocol in the server's list, since
// it presumedly has a better understanding of which protocol we should
// use, therefore the rest of the ordering here is not important.
static const char kNpnProtosFull[] = "\x08http/1.1\x06spdy/2";
// This is a temporary hack to pretend we support version 1.
static const char kNpnProtosFullV1[] = "\x08http/1.1\x06spdy/1";
// No spdy specified.
static const char kNpnProtosHttpOnly[] = "\x08http/1.1\x07http1.1";
std::vector<std::string> spdy_options;
base::SplitString(mode, ',', &spdy_options);
bool use_alt_protocols = true;
for (std::vector<std::string>::iterator it = spdy_options.begin();
it != spdy_options.end(); ++it) {
const std::string& element = *it;
std::vector<std::string> name_value;
base::SplitString(element, '=', &name_value);
const std::string& option = name_value[0];
const std::string value = name_value.size() > 1 ? name_value[1] : "";
if (option == kOff) {
HttpStreamFactory::set_spdy_enabled(false);
} else if (option == kDisableSSL) {
SpdySession::SetSSLMode(false); // Disable SSL
HttpStreamFactory::set_force_spdy_over_ssl(false);
HttpStreamFactory::set_force_spdy_always(true);
} else if (option == kSSL) {
HttpStreamFactory::set_force_spdy_over_ssl(true);
HttpStreamFactory::set_force_spdy_always(true);
} else if (option == kDisablePing) {
SpdySession::set_enable_ping_based_connection_checking(false);
} else if (option == kExclude) {
HttpStreamFactory::add_forced_spdy_exclusion(value);
} else if (option == kDisableCompression) {
spdy::SpdyFramer::set_enable_compression_default(false);
} else if (option == kEnableNPN) {
HttpStreamFactory::set_use_alternate_protocols(use_alt_protocols);
HttpStreamFactory::set_next_protos(kNpnProtosFull);
} else if (option == kEnableNpnHttpOnly) {
// Avoid alternate protocol in this case. Otherwise, browser will try SSL
// and then fallback to http. This introduces extra load.
HttpStreamFactory::set_use_alternate_protocols(false);
HttpStreamFactory::set_next_protos(kNpnProtosHttpOnly);
} else if (option == kEnableVersionOne) {
spdy::SpdyFramer::set_protocol_version(1);
HttpStreamFactory::set_next_protos(kNpnProtosFullV1);
} else if (option == kDisableAltProtocols) {
use_alt_protocols = false;
HttpStreamFactory::set_use_alternate_protocols(false);
} else if (option == kEnableFlowControl) {
SpdySession::set_flow_control(true);
} else if (option == kForceAltProtocols) {
HttpAlternateProtocols::PortProtocolPair pair;
pair.port = 443;
pair.protocol = HttpAlternateProtocols::NPN_SPDY_2;
HttpAlternateProtocols::ForceAlternateProtocol(pair);
} else if (option == kSingleDomain) {
SpdySessionPool::ForceSingleDomain();
LOG(ERROR) << "FORCING SINGLE DOMAIN";
} else if (option.empty() && it == spdy_options.begin()) {
continue;
} else {
LOG(DFATAL) << "Unrecognized spdy option: " << option;
}
}
}
//-----------------------------------------------------------------------------
int HttpNetworkLayer::CreateTransaction(scoped_ptr<HttpTransaction>* trans) {
if (suspended_)
return ERR_NETWORK_IO_SUSPENDED;
trans->reset(new HttpNetworkTransaction(GetSession()));
return OK;
}
HttpCache* HttpNetworkLayer::GetCache() {
return NULL;
}
HttpNetworkSession* HttpNetworkLayer::GetSession() {
return session_;
}
void HttpNetworkLayer::Suspend(bool suspend) {
suspended_ = suspend;
if (suspend && session_)
session_->CloseIdleConnections();
}
} // namespace net
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