content/browser/renderer_host/websocket_dispatcher_host.cc

   1 // Copyright 2013 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 "content/browser/renderer_host/websocket_dispatcher_host.h"
   6
   7 #include <string>
   8 #include <vector>
   9
  10 #include "base/callback.h"
  11 #include "base/logging.h"
  12 #include "base/numerics/safe_conversions.h"
  13 #include "base/rand_util.h"
  14 #include "base/stl_util.h"
  15 #include "content/browser/child_process_security_policy_impl.h"
  16 #include "content/browser/renderer_host/websocket_host.h"
  17 #include "content/common/websocket_messages.h"
  18
  19 namespace content {
  20
  21 namespace {
  22
  23 // Many methods defined in this file return a WebSocketHostState enum
  24 // value. Make WebSocketHostState visible at file scope so it doesn't have to be
  25 // fully-qualified every time.
  26 typedef WebSocketDispatcherHost::WebSocketHostState WebSocketHostState;
  27
  28 // Max number of pending connections per WebSocketDispatcherHost
  29 // used for per-renderer WebSocket throttling.
  30 const int kMaxPendingWebSocketConnections = 255;
  31
  32 }  // namespace
  33
  34 WebSocketDispatcherHost::WebSocketDispatcherHost(
  35     int process_id,
  36     const GetRequestContextCallback& get_context_callback)
  37     : BrowserMessageFilter(WebSocketMsgStart),
  38       process_id_(process_id),
  39       get_context_callback_(get_context_callback),
  40       websocket_host_factory_(
  41           base::Bind(&WebSocketDispatcherHost::CreateWebSocketHost,
  42                      base::Unretained(this))),
  43       num_pending_connections_(0),
  44       num_current_succeeded_connections_(0),
  45       num_previous_succeeded_connections_(0),
  46       num_current_failed_connections_(0),
  47       num_previous_failed_connections_(0) {}
  48
  49 WebSocketDispatcherHost::WebSocketDispatcherHost(
  50     int process_id,
  51     const GetRequestContextCallback& get_context_callback,
  52     const WebSocketHostFactory& websocket_host_factory)
  53     : BrowserMessageFilter(WebSocketMsgStart),
  54       process_id_(process_id),
  55       get_context_callback_(get_context_callback),
  56       websocket_host_factory_(websocket_host_factory),
  57       num_pending_connections_(0),
  58       num_current_succeeded_connections_(0),
  59       num_previous_succeeded_connections_(0),
  60       num_current_failed_connections_(0),
  61       num_previous_failed_connections_(0) {}
  62
  63 WebSocketHost* WebSocketDispatcherHost::CreateWebSocketHost(
  64     int routing_id,
  65     base::TimeDelta delay) {
  66   return new WebSocketHost(
  67       routing_id, this, get_context_callback_.Run(), delay);
  68 }
  69
  70 bool WebSocketDispatcherHost::OnMessageReceived(const IPC::Message& message) {
  71   switch (message.type()) {
  72     case WebSocketHostMsg_AddChannelRequest::ID:
  73     case WebSocketMsg_SendFrame::ID:
  74     case WebSocketMsg_FlowControl::ID:
  75     case WebSocketMsg_DropChannel::ID:
  76       break;
  77
  78     default:
  79       // Every message that has not been handled by a previous filter passes
  80       // through here, so it is good to pass them on as efficiently as possible.
  81       return false;
  82   }
  83
  84   int routing_id = message.routing_id();
  85   WebSocketHost* host = GetHost(routing_id);
  86   if (message.type() == WebSocketHostMsg_AddChannelRequest::ID) {
  87     if (host) {
  88       DVLOG(1) << "routing_id=" << routing_id << " already in use.";
  89       // The websocket multiplexing spec says to should drop the physical
  90       // connection in this case, but there isn't a real physical connection
  91       // to the renderer, and killing the renderer for this would seem to be a
  92       // little extreme. So for now just ignore the bogus request.
  93       return true;  // We handled the message (by ignoring it).
  94     }
  95     if (num_pending_connections_ >= kMaxPendingWebSocketConnections) {
  96       if(!Send(new WebSocketMsg_NotifyFailure(routing_id,
  97           "Error in connection establishment: net::ERR_INSUFFICIENT_RESOURCES"
  98           ))) {
  99         DVLOG(1) << "Sending of message type "
 100                  << "WebSocketMsg_NotifyFailure failed.";
 101       }
 102       return true;
 103     }
 104     host = websocket_host_factory_.Run(routing_id, CalculateDelay());
 105     hosts_.insert(WebSocketHostTable::value_type(routing_id, host));
 106     ++num_pending_connections_;
 107     if (!throttling_period_timer_.IsRunning())
 108       throttling_period_timer_.Start(
 109           FROM_HERE,
 110           base::TimeDelta::FromMinutes(2),
 111           this,
 112           &WebSocketDispatcherHost::ThrottlingPeriodTimerCallback);
 113   }
 114   if (!host) {
 115     DVLOG(1) << "Received invalid routing ID " << routing_id
 116              << " from renderer.";
 117     return true;  // We handled the message (by ignoring it).
 118   }
 119   return host->OnMessageReceived(message);
 120 }
 121
 122 bool WebSocketDispatcherHost::CanReadRawCookies() const {
 123   ChildProcessSecurityPolicyImpl* policy =
 124       ChildProcessSecurityPolicyImpl::GetInstance();
 125   return policy->CanReadRawCookies(process_id_);
 126 }
 127
 128 WebSocketHost* WebSocketDispatcherHost::GetHost(int routing_id) const {
 129   WebSocketHostTable::const_iterator it = hosts_.find(routing_id);
 130   return it == hosts_.end() ? NULL : it->second;
 131 }
 132
 133 WebSocketHostState WebSocketDispatcherHost::SendOrDrop(IPC::Message* message) {
 134   const uint32 message_type = message->type();
 135   const int32 message_routing_id = message->routing_id();
 136   if (!Send(message)) {
 137     message = NULL;
 138     DVLOG(1) << "Sending of message type " << message_type
 139              << " failed. Dropping channel.";
 140     DeleteWebSocketHost(message_routing_id);
 141     return WEBSOCKET_HOST_DELETED;
 142   }
 143   return WEBSOCKET_HOST_ALIVE;
 144 }
 145
 146 WebSocketHostState WebSocketDispatcherHost::SendAddChannelResponse(
 147     int routing_id,
 148     const std::string& selected_protocol,
 149     const std::string& extensions) {
 150   // Update throttling counters (success).
 151   WebSocketHost* host = GetHost(routing_id);
 152   DCHECK(host);
 153   host->OnHandshakeSucceeded();
 154   --num_pending_connections_;
 155   DCHECK_GE(num_pending_connections_, 0);
 156   ++num_current_succeeded_connections_;
 157
 158   return SendOrDrop(new WebSocketMsg_AddChannelResponse(
 159       routing_id, selected_protocol, extensions));
 160 }
 161
 162 WebSocketHostState WebSocketDispatcherHost::SendFrame(
 163     int routing_id,
 164     bool fin,
 165     WebSocketMessageType type,
 166     const std::vector<char>& data) {
 167   return SendOrDrop(new WebSocketMsg_SendFrame(routing_id, fin, type, data));
 168 }
 169
 170 WebSocketHostState WebSocketDispatcherHost::SendFlowControl(int routing_id,
 171                                                             int64 quota) {
 172   return SendOrDrop(new WebSocketMsg_FlowControl(routing_id, quota));
 173 }
 174
 175 WebSocketHostState WebSocketDispatcherHost::NotifyClosingHandshake(
 176     int routing_id) {
 177   return SendOrDrop(new WebSocketMsg_NotifyClosing(routing_id));
 178 }
 179
 180 WebSocketHostState WebSocketDispatcherHost::NotifyStartOpeningHandshake(
 181     int routing_id, const WebSocketHandshakeRequest& request) {
 182   return SendOrDrop(new WebSocketMsg_NotifyStartOpeningHandshake(
 183       routing_id, request));
 184 }
 185
 186 WebSocketHostState WebSocketDispatcherHost::NotifyFinishOpeningHandshake(
 187     int routing_id, const WebSocketHandshakeResponse& response) {
 188   return SendOrDrop(new WebSocketMsg_NotifyFinishOpeningHandshake(
 189       routing_id, response));
 190 }
 191
 192 WebSocketHostState WebSocketDispatcherHost::NotifyFailure(
 193     int routing_id,
 194     const std::string& message) {
 195   if (SendOrDrop(new WebSocketMsg_NotifyFailure(
 196           routing_id, message)) == WEBSOCKET_HOST_DELETED) {
 197     return WEBSOCKET_HOST_DELETED;
 198   }
 199   DeleteWebSocketHost(routing_id);
 200   return WEBSOCKET_HOST_DELETED;
 201 }
 202
 203 WebSocketHostState WebSocketDispatcherHost::DoDropChannel(
 204     int routing_id,
 205     bool was_clean,
 206     uint16 code,
 207     const std::string& reason) {
 208   if (SendOrDrop(
 209           new WebSocketMsg_DropChannel(routing_id, was_clean, code, reason)) ==
 210       WEBSOCKET_HOST_DELETED)
 211     return WEBSOCKET_HOST_DELETED;
 212   DeleteWebSocketHost(routing_id);
 213   return WEBSOCKET_HOST_DELETED;
 214 }
 215
 216 WebSocketDispatcherHost::~WebSocketDispatcherHost() {
 217   std::vector<WebSocketHost*> hosts;
 218   for (base::hash_map<int, WebSocketHost*>::const_iterator i = hosts_.begin();
 219        i != hosts_.end(); ++i) {
 220     // In order to avoid changing the container while iterating, we copy
 221     // the hosts.
 222     hosts.push_back(i->second);
 223   }
 224
 225   for (size_t i = 0; i < hosts.size(); ++i) {
 226     // Note that some calls to GoAway could fail. In that case hosts[i] will be
 227     // deleted and removed from |hosts_| in |DoDropChannel|.
 228     hosts[i]->GoAway();
 229     hosts[i] = NULL;
 230   }
 231
 232   STLDeleteContainerPairSecondPointers(hosts_.begin(), hosts_.end());
 233 }
 234
 235 void WebSocketDispatcherHost::DeleteWebSocketHost(int routing_id) {
 236   WebSocketHostTable::iterator it = hosts_.find(routing_id);
 237   DCHECK(it != hosts_.end());
 238   DCHECK(it->second);
 239   if (!it->second->handshake_succeeded()) {
 240     // Update throttling counters (failure).
 241     --num_pending_connections_;
 242     DCHECK_GE(num_pending_connections_, 0);
 243     ++num_current_failed_connections_;
 244   }
 245
 246   delete it->second;
 247   hosts_.erase(it);
 248
 249   DCHECK_LE(base::checked_cast<size_t>(num_pending_connections_),
 250             hosts_.size());
 251 }
 252
 253 int64_t WebSocketDispatcherHost::num_failed_connections() const {
 254   return num_previous_failed_connections_ +
 255          num_current_failed_connections_;
 256 }
 257
 258 int64_t WebSocketDispatcherHost::num_succeeded_connections() const {
 259   return num_previous_succeeded_connections_ +
 260          num_current_succeeded_connections_;
 261 }
 262
 263 // Calculate delay as described in
 264 // the per-renderer WebSocket throttling design doc:
 265 // https://docs.google.com/document/d/1aw2oN5PKfk-1gLnBrlv1OwLA8K3-ykM2ckwX2lubTg4/edit?usp=sharing
 266 base::TimeDelta WebSocketDispatcherHost::CalculateDelay() const {
 267   int64_t f = num_failed_connections();
 268   int64_t s = num_succeeded_connections();
 269   int p = num_pending_connections();
 270   return base::TimeDelta::FromMilliseconds(
 271       base::RandInt(1000, 5000) *
 272       (1 << std::min(p + f / (s + 1), INT64_C(16))) / 65536);
 273 }
 274
 275 void WebSocketDispatcherHost::ThrottlingPeriodTimerCallback() {
 276   num_previous_failed_connections_ = num_current_failed_connections_;
 277   num_current_failed_connections_ = 0;
 278
 279   num_previous_succeeded_connections_ = num_current_succeeded_connections_;
 280   num_current_succeeded_connections_ = 0;
 281
 282   if (num_pending_connections_ == 0 &&
 283       num_previous_failed_connections_ == 0 &&
 284       num_previous_succeeded_connections_ == 0) {
 285     throttling_period_timer_.Stop();
 286   }
 287 }
 288
 289 }  // namespace content