src/ppapi/host/ppapi_host.cc

   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 "ppapi/host/ppapi_host.h"
   6
   7 #include "base/logging.h"
   8 #include "ppapi/c/pp_errors.h"
   9 #include "ppapi/host/host_factory.h"
  10 #include "ppapi/host/host_message_context.h"
  11 #include "ppapi/host/instance_message_filter.h"
  12 #include "ppapi/host/resource_host.h"
  13 #include "ppapi/proxy/ppapi_messages.h"
  14 #include "ppapi/proxy/resource_message_params.h"
  15 #include "ppapi/proxy/serialized_handle.h"
  16 #include "ppapi/shared_impl/host_resource.h"
  17
  18 namespace ppapi {
  19 namespace host {
  20
  21 using proxy::SerializedHandle;
  22
  23 namespace {
  24
  25 // Put a cap on the maximum number of resources so we don't explode if the
  26 // renderer starts spamming us.
  27 const size_t kMaxResourcesPerPlugin = 1 << 14;
  28
  29 }  // namespace
  30
  31 PpapiHost::PpapiHost(IPC::Sender* sender,
  32                      const PpapiPermissions& perms)
  33     : sender_(sender),
  34       permissions_(perms),
  35       next_pending_resource_host_id_(1) {
  36 }
  37
  38 PpapiHost::~PpapiHost() {
  39   // Delete these explicitly before destruction since then the host is still
  40   // technically alive in case one of the filters accesses us from the
  41   // destructor.
  42   instance_message_filters_.clear();
  43
  44   // The resources may also want to use us in their destructors.
  45   resources_.clear();
  46   pending_resource_hosts_.clear();
  47 }
  48
  49 bool PpapiHost::Send(IPC::Message* msg) {
  50   return sender_->Send(msg);
  51 }
  52
  53 bool PpapiHost::OnMessageReceived(const IPC::Message& msg) {
  54   bool handled = true;
  55   IPC_BEGIN_MESSAGE_MAP(PpapiHost, msg)
  56     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCall,
  57                         OnHostMsgResourceCall)
  58     IPC_MESSAGE_HANDLER(PpapiHostMsg_InProcessResourceCall,
  59                         OnHostMsgInProcessResourceCall)
  60     IPC_MESSAGE_HANDLER_DELAY_REPLY(PpapiHostMsg_ResourceSyncCall,
  61                                     OnHostMsgResourceSyncCall)
  62     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceCreated,
  63                         OnHostMsgResourceCreated)
  64     IPC_MESSAGE_HANDLER(PpapiHostMsg_AttachToPendingHost,
  65                         OnHostMsgAttachToPendingHost)
  66     IPC_MESSAGE_HANDLER(PpapiHostMsg_ResourceDestroyed,
  67                         OnHostMsgResourceDestroyed)
  68     IPC_MESSAGE_UNHANDLED(handled = false)
  69   IPC_END_MESSAGE_MAP()
  70
  71   if (!handled) {
  72     for (size_t i = 0; i < instance_message_filters_.size(); i++) {
  73       if (instance_message_filters_[i]->OnInstanceMessageReceived(msg)) {
  74         handled = true;
  75         break;
  76       }
  77     }
  78   }
  79
  80   return handled;
  81 }
  82
  83 void PpapiHost::SendReply(const ReplyMessageContext& context,
  84                           const IPC::Message& msg) {
  85   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendReply",
  86                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
  87                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
  88   if (context.sync_reply_msg) {
  89     PpapiHostMsg_ResourceSyncCall::WriteReplyParams(context.sync_reply_msg,
  90                                                     context.params, msg);
  91     Send(context.sync_reply_msg);
  92   } else {
  93     if (context.routing_id != MSG_ROUTING_NONE) {
  94       Send(new PpapiHostMsg_InProcessResourceReply(context.routing_id,
  95                                                    context.params,
  96                                                    msg));
  97     } else {
  98       Send(new PpapiPluginMsg_ResourceReply(context.params, msg));
  99     }
 100   }
 101 }
 102
 103 void PpapiHost::SendUnsolicitedReply(PP_Resource resource,
 104                                      const IPC::Message& msg) {
 105   SendUnsolicitedReplyWithHandles(
 106       resource, msg, std::vector<SerializedHandle>());
 107 }
 108
 109 void PpapiHost::SendUnsolicitedReplyWithHandles(
 110     PP_Resource resource,
 111     const IPC::Message& msg,
 112     const std::vector<SerializedHandle>& handles) {
 113   TRACE_EVENT2("ppapi proxy", "PpapiHost::SendUnsolicitedReplyWithHandles",
 114                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
 115                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
 116   DCHECK(resource);  // If this fails, host is probably pending.
 117   proxy::ResourceMessageReplyParams params(resource, 0);
 118   for (std::vector<SerializedHandle>::const_iterator it = handles.begin();
 119       it != handles.end(); ++it) {
 120     params.AppendHandle(*it);
 121   }
 122   Send(new PpapiPluginMsg_ResourceReply(params, msg));
 123 }
 124
 125 scoped_ptr<ResourceHost> PpapiHost::CreateResourceHost(
 126     const proxy::ResourceMessageCallParams& params,
 127     PP_Instance instance,
 128     const IPC::Message& nested_msg) {
 129   scoped_ptr<ResourceHost> resource_host;
 130   DCHECK(!host_factory_filters_.empty());  // Caller forgot to add a factory.
 131   for (size_t i = 0; i < host_factory_filters_.size(); i++) {
 132     resource_host = host_factory_filters_[i]->CreateResourceHost(
 133         this, params, instance, nested_msg).Pass();
 134     if (resource_host.get())
 135       break;
 136   }
 137   return resource_host.Pass();
 138 }
 139
 140 int PpapiHost::AddPendingResourceHost(scoped_ptr<ResourceHost> resource_host) {
 141   // The resource ID should not be assigned.
 142   if (!resource_host.get() || resource_host->pp_resource() != 0) {
 143     NOTREACHED();
 144     return 0;
 145   }
 146
 147   if (pending_resource_hosts_.size() + resources_.size()
 148       >= kMaxResourcesPerPlugin) {
 149     return 0;
 150   }
 151
 152   int pending_id = next_pending_resource_host_id_++;
 153   pending_resource_hosts_[pending_id] =
 154       linked_ptr<ResourceHost>(resource_host.release());
 155   return pending_id;
 156 }
 157
 158 void PpapiHost::AddHostFactoryFilter(scoped_ptr<HostFactory> filter) {
 159   host_factory_filters_.push_back(filter.release());
 160 }
 161
 162 void PpapiHost::AddInstanceMessageFilter(
 163     scoped_ptr<InstanceMessageFilter> filter) {
 164   instance_message_filters_.push_back(filter.release());
 165 }
 166
 167 void PpapiHost::OnHostMsgResourceCall(
 168     const proxy::ResourceMessageCallParams& params,
 169     const IPC::Message& nested_msg) {
 170   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCall",
 171                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 172                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 173   HostMessageContext context(params);
 174   HandleResourceCall(params, nested_msg, &context);
 175 }
 176
 177 void PpapiHost::OnHostMsgInProcessResourceCall(
 178     int routing_id,
 179     const proxy::ResourceMessageCallParams& params,
 180     const IPC::Message& nested_msg) {
 181   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgInProcessResourceCall",
 182                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 183                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 184   HostMessageContext context(routing_id, params);
 185   HandleResourceCall(params, nested_msg, &context);
 186 }
 187
 188 void PpapiHost::OnHostMsgResourceSyncCall(
 189     const proxy::ResourceMessageCallParams& params,
 190     const IPC::Message& nested_msg,
 191     IPC::Message* reply_msg) {
 192   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceSyncCall",
 193                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 194                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 195   // Sync messages should always have callback set because they always expect
 196   // a reply from the host.
 197   DCHECK(params.has_callback());
 198   // Stash the |reply_msg| in the context so that it can be used to reply
 199   // to the sync message.
 200   HostMessageContext context(params, reply_msg);
 201   HandleResourceCall(params, nested_msg, &context);
 202 }
 203
 204 void PpapiHost::HandleResourceCall(
 205     const proxy::ResourceMessageCallParams& params,
 206     const IPC::Message& nested_msg,
 207     HostMessageContext* context) {
 208   ResourceHost* resource_host = GetResourceHost(params.pp_resource());
 209   if (resource_host) {
 210     // CAUTION: Handling the message may cause the destruction of this object.
 211     resource_host->HandleMessage(nested_msg, context);
 212   } else {
 213     if (context->params.has_callback()) {
 214       ReplyMessageContext reply_context = context->MakeReplyMessageContext();
 215       reply_context.params.set_result(PP_ERROR_BADRESOURCE);
 216       SendReply(reply_context, context->reply_msg);
 217     }
 218   }
 219 }
 220
 221 void PpapiHost::OnHostMsgResourceCreated(
 222     const proxy::ResourceMessageCallParams& params,
 223     PP_Instance instance,
 224     const IPC::Message& nested_msg) {
 225   TRACE_EVENT2("ppapi proxy", "PpapiHost::OnHostMsgResourceCreated",
 226                "Class", IPC_MESSAGE_ID_CLASS(nested_msg.type()),
 227                "Line", IPC_MESSAGE_ID_LINE(nested_msg.type()));
 228
 229   if (pending_resource_hosts_.size() + resources_.size()
 230       >= kMaxResourcesPerPlugin) {
 231     return;
 232   }
 233
 234   // Run through all filters until one grabs this message.
 235   scoped_ptr<ResourceHost> resource_host = CreateResourceHost(params, instance,
 236                                                               nested_msg);
 237
 238   if (!resource_host.get()) {
 239     NOTREACHED();
 240     return;
 241   }
 242
 243   // Resource should have been assigned a nonzero PP_Resource.
 244   DCHECK(resource_host->pp_resource());
 245
 246   resources_[params.pp_resource()] =
 247       linked_ptr<ResourceHost>(resource_host.release());
 248 }
 249
 250 void PpapiHost::OnHostMsgAttachToPendingHost(PP_Resource pp_resource,
 251                                              int pending_host_id) {
 252   PendingHostResourceMap::iterator found =
 253       pending_resource_hosts_.find(pending_host_id);
 254   if (found == pending_resource_hosts_.end()) {
 255     // Plugin sent a bad ID.
 256     NOTREACHED();
 257     return;
 258   }
 259   found->second->SetPPResourceForPendingHost(pp_resource);
 260   resources_[pp_resource] = found->second;
 261   pending_resource_hosts_.erase(found);
 262 }
 263
 264 void PpapiHost::OnHostMsgResourceDestroyed(PP_Resource resource) {
 265   ResourceMap::iterator found = resources_.find(resource);
 266   if (found == resources_.end()) {
 267     NOTREACHED();
 268     return;
 269   }
 270   // Invoking the HostResource destructor might result in looking up the
 271   // PP_Resource in resources_. std::map is not well specified as to whether the
 272   // element will be there or not. Therefore, we delay destruction of the
 273   // HostResource until after we've made sure the map no longer contains
 274   // |resource|.
 275   linked_ptr<ResourceHost> delete_at_end_of_scope(found->second);
 276   resources_.erase(found);
 277 }
 278
 279 ResourceHost* PpapiHost::GetResourceHost(PP_Resource resource) const {
 280   ResourceMap::const_iterator found = resources_.find(resource);
 281   return found == resources_.end() ? NULL : found->second.get();
 282 }
 283
 284 }  // namespace host
 285 }  // namespace ppapi