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Diffstat (limited to 'ipc/glue/NodeController.cpp')
| -rw-r--r-- | ipc/glue/NodeController.cpp | 856 |
1 files changed, 856 insertions, 0 deletions
diff --git a/ipc/glue/NodeController.cpp b/ipc/glue/NodeController.cpp new file mode 100644 index 0000000000..72e9b9a8fe --- /dev/null +++ b/ipc/glue/NodeController.cpp @@ -0,0 +1,856 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/ipc/NodeController.h" +#include "MainThreadUtils.h" +#include "base/process_util.h" +#include "chrome/common/ipc_message.h" +#include "mojo/core/ports/name.h" +#include "mojo/core/ports/node.h" +#include "mozilla/AlreadyAddRefed.h" +#include "mozilla/RandomNum.h" +#include "mozilla/StaticPtr.h" +#include "mozilla/Assertions.h" +#include "mozilla/ToString.h" +#include "mozilla/ipc/BrowserProcessSubThread.h" +#include "mozilla/ipc/ProtocolUtils.h" +#include "mozilla/mozalloc.h" +#include "nsISerialEventTarget.h" +#include "nsTArray.h" +#include "nsXULAppAPI.h" +#include "nsPrintfCString.h" + +#define PORTS_ALWAYS_OK(expr) MOZ_ALWAYS_TRUE(mojo::core::ports::OK == (expr)) + +namespace mozilla::ipc { + +static StaticRefPtr<NodeController> gNodeController; + +static LazyLogModule gNodeControllerLog{"NodeController"}; + +// Helper logger macro which includes the name of the `this` NodeController in +// the logged messages. +#define NODECONTROLLER_LOG(level_, fmt_, ...) \ + MOZ_LOG(gNodeControllerLog, level_, \ + ("[%s]: " fmt_, ToString(mName).c_str(), ##__VA_ARGS__)) + +// Helper warning macro which both does logger logging and emits NS_WARNING logs +// under debug mode. +#ifdef DEBUG +# define NODECONTROLLER_WARNING(fmt_, ...) \ + do { \ + nsPrintfCString warning("[%s]: " fmt_, ToString(mName).c_str(), \ + ##__VA_ARGS__); \ + NS_WARNING(warning.get()); \ + MOZ_LOG(gNodeControllerLog, LogLevel::Debug, ("%s", warning.get())); \ + } while (0) +#else +# define NODECONTROLLER_WARNING(fmt_, ...) \ + NODECONTROLLER_LOG(LogLevel::Warning, fmt_, ##__VA_ARGS__) +#endif + +NodeController::NodeController(const NodeName& aName) + : mName(aName), mNode(MakeUnique<Node>(aName, this)) {} + +NodeController::~NodeController() { + auto state = mState.Lock(); + MOZ_RELEASE_ASSERT(state->mPeers.IsEmpty(), + "Destroying NodeController before closing all peers"); + MOZ_RELEASE_ASSERT(state->mInvites.IsEmpty(), + "Destroying NodeController before closing all invites"); +}; + +// FIXME: Actually provide some way to create the thing. +/* static */ NodeController* NodeController::GetSingleton() { + MOZ_ASSERT(gNodeController); + return gNodeController; +} + +std::pair<ScopedPort, ScopedPort> NodeController::CreatePortPair() { + PortRef port0, port1; + PORTS_ALWAYS_OK(mNode->CreatePortPair(&port0, &port1)); + return {ScopedPort{std::move(port0), this}, + ScopedPort{std::move(port1), this}}; +} + +auto NodeController::GetPort(const PortName& aName) -> PortRef { + PortRef port; + int rv = mNode->GetPort(aName, &port); + if (NS_WARN_IF(rv != mojo::core::ports::OK)) { + NODECONTROLLER_WARNING("Call to GetPort(%s) Failed", + ToString(aName).c_str()); + return {}; + } + return port; +} + +void NodeController::SetPortObserver(const PortRef& aPort, + PortObserver* aObserver) { + PORTS_ALWAYS_OK(mNode->SetUserData(aPort, aObserver)); +} + +auto NodeController::GetStatus(const PortRef& aPort) -> Maybe<PortStatus> { + PortStatus status{}; + int rv = mNode->GetStatus(aPort, &status); + if (rv != mojo::core::ports::OK) { + return Nothing(); + } + return Some(status); +} + +void NodeController::ClosePort(const PortRef& aPort) { + PORTS_ALWAYS_OK(mNode->ClosePort(aPort)); +} + +bool NodeController::GetMessage(const PortRef& aPort, + UniquePtr<IPC::Message>* aMessage) { + UniquePtr<UserMessageEvent> messageEvent; + int rv = mNode->GetMessage(aPort, &messageEvent, nullptr); + if (rv != mojo::core::ports::OK) { + if (rv == mojo::core::ports::ERROR_PORT_PEER_CLOSED) { + return false; + } + MOZ_CRASH("GetMessage on port in invalid state"); + } + + if (messageEvent) { + UniquePtr<IPC::Message> message = messageEvent->TakeMessage<IPC::Message>(); + + // If our UserMessageEvent has any ports directly attached to it, fetch them + // from our node and attach them to the IPC::Message we extracted. + // + // It's important to only do this if we have nonempty set of ports on the + // event, as we may have never serialized our IPC::Message's ports onto the + // event if it was routed in-process. + if (messageEvent->num_ports() > 0) { + nsTArray<ScopedPort> attachedPorts(messageEvent->num_ports()); + for (size_t i = 0; i < messageEvent->num_ports(); ++i) { + attachedPorts.AppendElement( + ScopedPort{GetPort(messageEvent->ports()[i]), this}); + } + message->SetAttachedPorts(std::move(attachedPorts)); + } + + *aMessage = std::move(message); + } else { + *aMessage = nullptr; + } + return true; +} + +bool NodeController::SendUserMessage(const PortRef& aPort, + UniquePtr<IPC::Message> aMessage) { + auto messageEvent = MakeUnique<UserMessageEvent>(0); + messageEvent->AttachMessage(std::move(aMessage)); + + int rv = mNode->SendUserMessage(aPort, std::move(messageEvent)); + if (rv == mojo::core::ports::OK) { + return true; + } + if (rv == mojo::core::ports::ERROR_PORT_PEER_CLOSED) { + NODECONTROLLER_LOG(LogLevel::Debug, + "Ignoring message to port %s as peer was closed", + ToString(aPort.name()).c_str()); + return true; + } + NODECONTROLLER_WARNING("Failed to send message to port %s", + ToString(aPort.name()).c_str()); + return false; +} + +auto NodeController::SerializeEventMessage(UniquePtr<Event> aEvent, + const NodeName* aRelayTarget, + uint32_t aType) + -> UniquePtr<IPC::Message> { + UniquePtr<IPC::Message> message; + if (aEvent->type() == Event::kUserMessage) { + MOZ_DIAGNOSTIC_ASSERT( + aType == EVENT_MESSAGE_TYPE, + "Can only send a UserMessage in an EVENT_MESSAGE_TYPE"); + message = static_cast<UserMessageEvent*>(aEvent.get()) + ->TakeMessage<IPC::Message>(); + } else { + message = MakeUnique<IPC::Message>(MSG_ROUTING_CONTROL, aType); + } + + message->set_relay(aRelayTarget != nullptr); + + size_t length = aEvent->GetSerializedSize(); + if (aRelayTarget) { + length += sizeof(NodeName); + } + + // Use an intermediate buffer to serialize to avoid potential issues with the + // segmented `IPC::Message` bufferlist. This should be fairly cheap, as the + // majority of events are fairly small. + Vector<char, 256, InfallibleAllocPolicy> buffer; + (void)buffer.initLengthUninitialized(length); + if (aRelayTarget) { + memcpy(buffer.begin(), aRelayTarget, sizeof(NodeName)); + aEvent->Serialize(buffer.begin() + sizeof(NodeName)); + } else { + aEvent->Serialize(buffer.begin()); + } + + message->WriteFooter(buffer.begin(), buffer.length()); + message->set_event_footer_size(buffer.length()); + +#ifdef DEBUG + // Debug-assert that we can read the same data back out of the buffer. + MOZ_ASSERT(message->event_footer_size() == length); + Vector<char, 256, InfallibleAllocPolicy> buffer2; + (void)buffer2.initLengthUninitialized(message->event_footer_size()); + MOZ_ASSERT(message->ReadFooter(buffer2.begin(), buffer2.length(), + /* truncate */ false)); + MOZ_ASSERT(!memcmp(buffer2.begin(), buffer.begin(), buffer.length())); +#endif + + return message; +} + +auto NodeController::DeserializeEventMessage(UniquePtr<IPC::Message> aMessage, + NodeName* aRelayTarget) + -> UniquePtr<Event> { + if (aMessage->is_relay() && !aRelayTarget) { + NODECONTROLLER_WARNING("Unexpected relay message '%s'", aMessage->name()); + return nullptr; + } + + Vector<char, 256, InfallibleAllocPolicy> buffer; + (void)buffer.initLengthUninitialized(aMessage->event_footer_size()); + // Truncate the message when reading the footer, so that the extra footer data + // is no longer present in the message. This allows future code to eventually + // send the same `IPC::Message` to another process. + if (!aMessage->ReadFooter(buffer.begin(), buffer.length(), + /* truncate */ true)) { + NODECONTROLLER_WARNING("Call to ReadFooter for message '%s' Failed", + aMessage->name()); + return nullptr; + } + aMessage->set_event_footer_size(0); + + UniquePtr<Event> event; + if (aRelayTarget) { + MOZ_ASSERT(aMessage->is_relay()); + if (buffer.length() < sizeof(NodeName)) { + NODECONTROLLER_WARNING( + "Insufficient space in message footer for message '%s'", + aMessage->name()); + return nullptr; + } + memcpy(aRelayTarget, buffer.begin(), sizeof(NodeName)); + event = Event::Deserialize(buffer.begin() + sizeof(NodeName), + buffer.length() - sizeof(NodeName)); + } else { + event = Event::Deserialize(buffer.begin(), buffer.length()); + } + + if (!event) { + NODECONTROLLER_WARNING("Call to Event::Deserialize for message '%s' Failed", + aMessage->name()); + return nullptr; + } + + if (event->type() == Event::kUserMessage) { + static_cast<UserMessageEvent*>(event.get()) + ->AttachMessage(std::move(aMessage)); + } + return event; +} + +already_AddRefed<NodeChannel> NodeController::GetNodeChannel( + const NodeName& aName) { + auto state = mState.Lock(); + return do_AddRef(state->mPeers.Get(aName)); +} + +void NodeController::DropPeer(NodeName aNodeName) { + AssertIOThread(); + +#ifdef FUZZING_SNAPSHOT + MOZ_FUZZING_IPC_DROP_PEER("NodeController::DropPeer"); +#endif + + Invite invite; + RefPtr<NodeChannel> channel; + nsTArray<PortRef> pendingMerges; + { + auto state = mState.Lock(); + state->mPeers.Remove(aNodeName, &channel); + state->mPendingMessages.Remove(aNodeName); + state->mInvites.Remove(aNodeName, &invite); + state->mPendingMerges.Remove(aNodeName, &pendingMerges); + } + + NODECONTROLLER_LOG(LogLevel::Info, "Dropping Peer %s (pid: %" PRIPID ")", + ToString(aNodeName).c_str(), + channel ? channel->OtherPid() : base::kInvalidProcessId); + + if (channel) { + channel->Close(); + } + if (invite.mChannel) { + invite.mChannel->Close(); + } + if (invite.mToMerge.is_valid()) { + // Ignore any possible errors here. + (void)mNode->ClosePort(invite.mToMerge); + } + for (auto& port : pendingMerges) { + // Ignore any possible errors here. + (void)mNode->ClosePort(port); + } + mNode->LostConnectionToNode(aNodeName); +} + +void NodeController::ForwardEvent(const NodeName& aNode, + UniquePtr<Event> aEvent) { + if (aNode == mName) { + (void)mNode->AcceptEvent(std::move(aEvent)); + } else { + // On Windows and macOS, messages holding HANDLEs or mach ports must be + // relayed via the broker process so it can transfer ownership. + bool needsRelay = false; +#if defined(XP_WIN) || defined(XP_MACOSX) + if (!IsBroker() && aNode != kBrokerNodeName && + aEvent->type() == Event::kUserMessage) { + auto* userEvent = static_cast<UserMessageEvent*>(aEvent.get()); + needsRelay = + userEvent->HasMessage() && + userEvent->GetMessage<IPC::Message>()->num_relayed_attachments() > 0; + } +#endif + + UniquePtr<IPC::Message> message = + SerializeEventMessage(std::move(aEvent), needsRelay ? &aNode : nullptr); + MOZ_ASSERT(message->is_relay() == needsRelay, + "Message relay status set incorrectly"); + + RefPtr<NodeChannel> peer; + RefPtr<NodeChannel> broker; + bool needsIntroduction = false; + { + auto state = mState.Lock(); + + // Check if we know this peer. If we don't, we'll need to request an + // introduction. + peer = state->mPeers.Get(aNode); + if (!peer || needsRelay) { + if (IsBroker()) { + NODECONTROLLER_WARNING("Ignoring message '%s' to unknown peer %s", + message->name(), ToString(aNode).c_str()); + return; + } + + broker = state->mPeers.Get(kBrokerNodeName); + if (!broker) { + NODECONTROLLER_WARNING( + "Ignoring message '%s' to peer %s due to a missing broker", + message->name(), ToString(aNode).c_str()); + return; + } + + if (!needsRelay) { + auto& queue = + state->mPendingMessages.LookupOrInsertWith(aNode, [&]() { + needsIntroduction = true; + return Queue<UniquePtr<IPC::Message>, 64>{}; + }); + queue.Push(std::move(message)); + } + } + } + + MOZ_ASSERT(!needsIntroduction || !needsRelay, + "Only one of the two should ever be set"); + + if (needsRelay) { + NODECONTROLLER_LOG(LogLevel::Info, + "Relaying message '%s' for peer %s due to %" PRIu32 + " attachments", + message->name(), ToString(aNode).c_str(), + message->num_relayed_attachments()); + MOZ_ASSERT(message->num_relayed_attachments() > 0 && broker); + broker->SendEventMessage(std::move(message)); + } else if (needsIntroduction) { + MOZ_ASSERT(broker); + broker->RequestIntroduction(aNode); + } else if (peer) { + peer->SendEventMessage(std::move(message)); + } + } +} + +void NodeController::BroadcastEvent(UniquePtr<Event> aEvent) { + UniquePtr<IPC::Message> message = + SerializeEventMessage(std::move(aEvent), nullptr, BROADCAST_MESSAGE_TYPE); + + if (IsBroker()) { + OnBroadcast(mName, std::move(message)); + } else if (RefPtr<NodeChannel> broker = GetNodeChannel(kBrokerNodeName)) { + broker->Broadcast(std::move(message)); + } else { + NODECONTROLLER_WARNING( + "Trying to broadcast event, but no connection to broker"); + } +} + +void NodeController::PortStatusChanged(const PortRef& aPortRef) { + RefPtr<UserData> userData; + int rv = mNode->GetUserData(aPortRef, &userData); + if (rv != mojo::core::ports::OK) { + NODECONTROLLER_WARNING("GetUserData call for port '%s' failed", + ToString(aPortRef.name()).c_str()); + return; + } + if (userData) { + // All instances of `UserData` attached to ports in this node must be of + // type `PortObserver`, so we can call `OnPortStatusChanged` directly on + // them. + static_cast<PortObserver*>(userData.get())->OnPortStatusChanged(); + } +} + +void NodeController::OnEventMessage(const NodeName& aFromNode, + UniquePtr<IPC::Message> aMessage) { + AssertIOThread(); + + bool isRelay = aMessage->is_relay(); + if (isRelay && aMessage->num_relayed_attachments() == 0) { + NODECONTROLLER_WARNING( + "Invalid relay message without relayed attachments from peer %s!", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + + NodeName relayTarget; + UniquePtr<Event> event = DeserializeEventMessage( + std::move(aMessage), isRelay ? &relayTarget : nullptr); + if (!event) { + NODECONTROLLER_WARNING("Invalid EventMessage from peer %s!", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + + NodeName fromNode = aFromNode; +#if defined(XP_WIN) || defined(XP_MACOSX) + if (isRelay) { + if (event->type() != Event::kUserMessage) { + NODECONTROLLER_WARNING( + "Unexpected relay of non-UserMessage event from peer %s!", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + + // If we're the broker, then we'll need to forward this message on to the + // true recipient. To do this, we re-serialize the message, passing along + // the original source node, and send it to the final node. + if (IsBroker()) { + UniquePtr<IPC::Message> message = + SerializeEventMessage(std::move(event), &aFromNode); + if (!message) { + NODECONTROLLER_WARNING( + "Relaying EventMessage from peer %s failed to re-serialize!", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + MOZ_ASSERT(message->is_relay(), "Message stopped being a relay message?"); + MOZ_ASSERT(message->num_relayed_attachments() > 0, + "Message doesn't have relayed attachments?"); + + NODECONTROLLER_LOG( + LogLevel::Info, + "Relaying message '%s' from peer %s to peer %s (%" PRIu32 + " attachments)", + message->name(), ToString(aFromNode).c_str(), + ToString(relayTarget).c_str(), message->num_relayed_attachments()); + + RefPtr<NodeChannel> peer; + { + auto state = mState.Lock(); + peer = state->mPeers.Get(relayTarget); + } + if (!peer) { + NODECONTROLLER_WARNING( + "Dropping relayed message from %s to unknown peer %s", + ToString(aFromNode).c_str(), ToString(relayTarget).c_str()); + return; + } + + peer->SendEventMessage(std::move(message)); + return; + } + + // Otherwise, we're the final recipient, so we can continue & process the + // message as usual. + if (aFromNode != kBrokerNodeName) { + NODECONTROLLER_WARNING( + "Unexpected relayed EventMessage from non-broker peer %s!", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + fromNode = relayTarget; + + NODECONTROLLER_LOG(LogLevel::Info, "Got relayed message from peer %s", + ToString(fromNode).c_str()); + } +#endif + + // If we're getting a requested port merge from another process, check to make + // sure that we're expecting the request, and record that the merge has + // arrived so we don't try to close the port on error. + if (event->type() == Event::kMergePort) { + // Check that the target port for the merge actually exists. + auto targetPort = GetPort(event->port_name()); + if (!targetPort.is_valid()) { + NODECONTROLLER_WARNING( + "Unexpected MergePortEvent from peer %s for unknown port %s", + ToString(fromNode).c_str(), ToString(event->port_name()).c_str()); + DropPeer(fromNode); + return; + } + + // Check if `targetPort` is in our pending merges entry for the given source + // node. If this makes the `mPendingMerges` entry empty, remove it. + bool expectingMerge = [&] { + auto state = mState.Lock(); + auto pendingMerges = state->mPendingMerges.Lookup(aFromNode); + if (!pendingMerges) { + return false; + } + size_t removed = pendingMerges->RemoveElementsBy( + [&](auto& port) { return port.name() == targetPort.name(); }); + if (removed != 0 && pendingMerges->IsEmpty()) { + pendingMerges.Remove(); + } + return removed != 0; + }(); + + if (!expectingMerge) { + NODECONTROLLER_WARNING( + "Unexpected MergePortEvent from peer %s for port %s", + ToString(fromNode).c_str(), ToString(event->port_name()).c_str()); + DropPeer(fromNode); + return; + } + } + + (void)mNode->AcceptEvent(std::move(event)); +} + +void NodeController::OnBroadcast(const NodeName& aFromNode, + UniquePtr<IPC::Message> aMessage) { + MOZ_DIAGNOSTIC_ASSERT(aMessage->type() == BROADCAST_MESSAGE_TYPE); + + // NOTE: This method may be called off of the IO thread by the + // `BroadcastEvent` node callback. + if (!IsBroker()) { + NODECONTROLLER_WARNING("Broadcast request received by non-broker node"); + return; + } + + UniquePtr<Event> event = DeserializeEventMessage(std::move(aMessage)); + if (!event) { + NODECONTROLLER_WARNING("Invalid broadcast message from peer"); + return; + } + + nsTArray<RefPtr<NodeChannel>> peers; + { + auto state = mState.Lock(); + peers.SetCapacity(state->mPeers.Count()); + for (const auto& peer : state->mPeers.Values()) { + peers.AppendElement(peer); + } + } + for (const auto& peer : peers) { + // NOTE: This `clone` operation is only supported for a limited number of + // message types by the ports API, which provides some extra security by + // only allowing those specific types of messages to be broadcasted. + // Messages which don't support `Clone` cannot be broadcast, and the ports + // library will not attempt to broadcast them. + auto clone = event->Clone(); + if (!clone) { + NODECONTROLLER_WARNING("Attempt to broadcast unsupported message"); + break; + } + + peer->SendEventMessage(SerializeEventMessage(std::move(clone))); + } +} + +void NodeController::OnIntroduce(const NodeName& aFromNode, + NodeChannel::Introduction aIntroduction) { + AssertIOThread(); + + if (aFromNode != kBrokerNodeName) { + NODECONTROLLER_WARNING("Introduction received from non-broker node"); + DropPeer(aFromNode); + return; + } + + MOZ_ASSERT(aIntroduction.mMyPid == base::GetCurrentProcId(), + "We're the wrong process to receive this?"); + + if (!aIntroduction.mHandle) { + NODECONTROLLER_WARNING("Could not be introduced to peer %s", + ToString(aIntroduction.mName).c_str()); + mNode->LostConnectionToNode(aIntroduction.mName); + + auto state = mState.Lock(); + state->mPendingMessages.Remove(aIntroduction.mName); + return; + } + + auto channel = MakeUnique<IPC::Channel>(std::move(aIntroduction.mHandle), + aIntroduction.mMode, nullptr); + auto nodeChannel = MakeRefPtr<NodeChannel>( + aIntroduction.mName, std::move(channel), this, aIntroduction.mOtherPid); + + { + auto state = mState.Lock(); + bool isNew = false; + state->mPeers.LookupOrInsertWith(aIntroduction.mName, [&]() { + isNew = true; + return nodeChannel; + }); + if (!isNew) { + // We got a duplicate introduction. This can happen during normal + // execution if both sides request an introduction at the same time. We + // can just ignore the second one, as they'll arrive in the same order in + // both processes. + nodeChannel->Close(); + return; + } + + // Deliver any pending messages, then remove the entry from our table. We do + // this while `mState` is still held to ensure that these messages are + // all sent before another thread can observe the newly created channel. + // As the channel hasn't been `Connect()`-ed yet, this will only queue the + // messages up to be sent, so is OK to do with the mutex held. These + // messages will be processed to be sent during `Start()` below, which is + // performed outside of the lock. + if (auto pending = state->mPendingMessages.Lookup(aIntroduction.mName)) { + while (!pending->IsEmpty()) { + nodeChannel->SendEventMessage(pending->Pop()); + } + pending.Remove(); + } + } + + // NodeChannel::Start must be called with the lock not held, as it may lead to + // callbacks being made into `OnChannelError` or `OnMessageReceived`, which + // will attempt to re-acquire our lock. + nodeChannel->Start(); +} + +void NodeController::OnRequestIntroduction(const NodeName& aFromNode, + const NodeName& aName) { + AssertIOThread(); + if (NS_WARN_IF(!IsBroker())) { + return; + } + + RefPtr<NodeChannel> peerA = GetNodeChannel(aFromNode); + if (!peerA || aName == mojo::core::ports::kInvalidNodeName) { + NODECONTROLLER_WARNING("Invalid OnRequestIntroduction message from node %s", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + + RefPtr<NodeChannel> peerB = GetNodeChannel(aName); + IPC::Channel::ChannelHandle handleA, handleB; + if (!peerB || !IPC::Channel::CreateRawPipe(&handleA, &handleB)) { + NODECONTROLLER_WARNING( + "Rejecting introduction request from '%s' for unknown peer '%s'", + ToString(aFromNode).c_str(), ToString(aName).c_str()); + + // We don't know this peer, or ran into issues creating the descriptor! Send + // an invalid introduction to content to clean up any pending outbound + // messages. + NodeChannel::Introduction intro{aName, nullptr, IPC::Channel::MODE_SERVER, + peerA->OtherPid(), base::kInvalidProcessId}; + peerA->Introduce(std::move(intro)); + return; + } + + NodeChannel::Introduction introA{aName, std::move(handleA), + IPC::Channel::MODE_SERVER, peerA->OtherPid(), + peerB->OtherPid()}; + NodeChannel::Introduction introB{aFromNode, std::move(handleB), + IPC::Channel::MODE_CLIENT, peerB->OtherPid(), + peerA->OtherPid()}; + peerA->Introduce(std::move(introA)); + peerB->Introduce(std::move(introB)); +} + +void NodeController::OnAcceptInvite(const NodeName& aFromNode, + const NodeName& aRealName, + const PortName& aInitialPort) { + AssertIOThread(); + if (!IsBroker()) { + NODECONTROLLER_WARNING("Ignoring AcceptInvite message as non-broker"); + return; + } + + if (aRealName == mojo::core::ports::kInvalidNodeName || + aInitialPort == mojo::core::ports::kInvalidPortName) { + NODECONTROLLER_WARNING("Invalid name in AcceptInvite message"); + DropPeer(aFromNode); + return; + } + + bool inserted = false; + Invite invite; + { + auto state = mState.Lock(); + MOZ_ASSERT(state->mPendingMessages.IsEmpty(), + "Shouldn't have pending messages in broker"); + + // Try to remove the source node from our invites list and insert it into + // our peers map under the new name. + if (state->mInvites.Remove(aFromNode, &invite)) { + MOZ_ASSERT(invite.mChannel && invite.mToMerge.is_valid()); + state->mPeers.LookupOrInsertWith(aRealName, [&]() { + inserted = true; + return invite.mChannel; + }); + } + } + if (!inserted) { + NODECONTROLLER_WARNING("Invalid AcceptInvite message from node %s", + ToString(aFromNode).c_str()); + DropPeer(aFromNode); + return; + } + + // Update the name of the node. This field is only accessed from the IO + // thread, so it's safe to update it without a lock held. + invite.mChannel->SetName(aRealName); + + // Start the port merge to allow our existing initial port to begin + // communicating with the remote port. + PORTS_ALWAYS_OK(mNode->MergePorts(invite.mToMerge, aRealName, aInitialPort)); +} + +void NodeController::OnChannelError(const NodeName& aFromNode) { + AssertIOThread(); + DropPeer(aFromNode); +} + +static mojo::core::ports::NodeName RandomNodeName() { + return {RandomUint64OrDie(), RandomUint64OrDie()}; +} + +std::tuple<ScopedPort, RefPtr<NodeChannel>> NodeController::InviteChildProcess( + UniquePtr<IPC::Channel> aChannel) { + MOZ_ASSERT(IsBroker()); + AssertIOThread(); + + // Create the peer with a randomly generated name, and store it in `mInvites`. + // This channel and name will be used for communication with the node until it + // sends us its' real name in an `AcceptInvite` message. + auto ports = CreatePortPair(); + auto inviteName = RandomNodeName(); + auto nodeChannel = + MakeRefPtr<NodeChannel>(inviteName, std::move(aChannel), this); + { + auto state = mState.Lock(); + MOZ_DIAGNOSTIC_ASSERT(!state->mPeers.Contains(inviteName), + "UUID conflict?"); + MOZ_DIAGNOSTIC_ASSERT(!state->mInvites.Contains(inviteName), + "UUID conflict?"); + state->mInvites.InsertOrUpdate(inviteName, + Invite{nodeChannel, ports.second.Release()}); + } + + nodeChannel->Start(/* aCallConnect */ false); + return std::tuple{std::move(ports.first), std::move(nodeChannel)}; +} + +void NodeController::InitBrokerProcess() { + AssertIOThread(); + MOZ_ASSERT(!gNodeController); + gNodeController = new NodeController(kBrokerNodeName); +} + +ScopedPort NodeController::InitChildProcess(UniquePtr<IPC::Channel> aChannel, + int32_t aParentPid) { + AssertIOThread(); + MOZ_ASSERT(!gNodeController); + + auto nodeName = RandomNodeName(); + gNodeController = new NodeController(nodeName); + + auto ports = gNodeController->CreatePortPair(); + PortRef toMerge = ports.second.Release(); + + auto nodeChannel = MakeRefPtr<NodeChannel>( + kBrokerNodeName, std::move(aChannel), gNodeController, aParentPid); + { + auto state = gNodeController->mState.Lock(); + MOZ_DIAGNOSTIC_ASSERT(!state->mPeers.Contains(kBrokerNodeName)); + state->mPeers.InsertOrUpdate(kBrokerNodeName, nodeChannel); + MOZ_DIAGNOSTIC_ASSERT(!state->mPendingMerges.Contains(kBrokerNodeName)); + state->mPendingMerges.LookupOrInsert(kBrokerNodeName) + .AppendElement(toMerge); + } + + nodeChannel->Start(/* aCallConnect */ true); + nodeChannel->AcceptInvite(nodeName, toMerge.name()); + return std::move(ports.first); +} + +void NodeController::CleanUp() { + AssertIOThread(); + MOZ_ASSERT(gNodeController); + + RefPtr<NodeController> nodeController = gNodeController; + gNodeController = nullptr; + + // Collect all objects from our state which need to be cleaned up. + nsTArray<NodeName> lostConnections; + nsTArray<RefPtr<NodeChannel>> channelsToClose; + nsTArray<PortRef> portsToClose; + { + auto state = nodeController->mState.Lock(); + for (const auto& chan : state->mPeers) { + lostConnections.AppendElement(chan.GetKey()); + channelsToClose.AppendElement(chan.GetData()); + } + for (const auto& invite : state->mInvites.Values()) { + channelsToClose.AppendElement(invite.mChannel); + portsToClose.AppendElement(invite.mToMerge); + } + for (const auto& pendingPorts : state->mPendingMerges.Values()) { + portsToClose.AppendElements(pendingPorts); + } + state->mPeers.Clear(); + state->mPendingMessages.Clear(); + state->mInvites.Clear(); + state->mPendingMerges.Clear(); + } + for (auto& nodeChannel : channelsToClose) { + nodeChannel->Close(); + } + for (auto& port : portsToClose) { + nodeController->mNode->ClosePort(port); + } + for (auto& name : lostConnections) { + nodeController->mNode->LostConnectionToNode(name); + } +} + +#undef NODECONTROLLER_LOG +#undef NODECONTROLLER_WARNING + +} // namespace mozilla::ipc |