From 8cb65fe65a48988d40dd3ca2c4f673629a275b4b Mon Sep 17 00:00:00 2001 From: Yuri Kunde Schlesner Date: Fri, 9 Jun 2017 05:23:13 -0700 Subject: [PATCH] Kernel: Basic support for IPC translation for HLE services --- src/core/hle/kernel/hle_ipc.cpp | 94 ++++++++++++++++++++++++++++++-- src/core/hle/kernel/hle_ipc.h | 37 ++++++++++++- src/core/hle/service/service.cpp | 17 ++---- 3 files changed, 130 insertions(+), 18 deletions(-) diff --git a/src/core/hle/kernel/hle_ipc.cpp b/src/core/hle/kernel/hle_ipc.cpp index 5a74645c7a..656405dd62 100644 --- a/src/core/hle/kernel/hle_ipc.cpp +++ b/src/core/hle/kernel/hle_ipc.cpp @@ -8,6 +8,7 @@ #include "core/hle/kernel/handle_table.h" #include "core/hle/kernel/hle_ipc.h" #include "core/hle/kernel/kernel.h" +#include "core/hle/kernel/process.h" #include "core/hle/kernel/server_session.h" namespace Kernel { @@ -24,12 +25,97 @@ void SessionRequestHandler::ClientDisconnected(SharedPtr server_s HLERequestContext::~HLERequestContext() = default; -SharedPtr HLERequestContext::GetIncomingHandle(Handle id_from_cmdbuf) const { - return Kernel::g_handle_table.GetGeneric(id_from_cmdbuf); +SharedPtr HLERequestContext::GetIncomingHandle(u32 id_from_cmdbuf) const { + ASSERT(id_from_cmdbuf < request_handles.size()); + return request_handles[id_from_cmdbuf]; } -Handle HLERequestContext::AddOutgoingHandle(SharedPtr object) { - return Kernel::g_handle_table.Create(object).Unwrap(); +u32 HLERequestContext::AddOutgoingHandle(SharedPtr object) { + request_handles.push_back(std::move(object)); + return request_handles.size() - 1; +} + +ResultCode HLERequestContext::PopulateFromIncomingCommandBuffer(const u32_le* src_cmdbuf, + Process& src_process, + HandleTable& src_table) { + IPC::Header header{src_cmdbuf[0]}; + + size_t untranslated_size = 1u + header.normal_params_size; + size_t command_size = untranslated_size + header.translate_params_size; + ASSERT(command_size <= IPC::COMMAND_BUFFER_LENGTH); // TODO(yuriks): Return error + + std::copy_n(src_cmdbuf, untranslated_size, cmd_buf.begin()); + + size_t i = untranslated_size; + while (i < command_size) { + u32 descriptor = cmd_buf[i] = src_cmdbuf[i]; + i += 1; + + switch (IPC::GetDescriptorType(descriptor)) { + case IPC::DescriptorType::CopyHandle: + case IPC::DescriptorType::MoveHandle: { + u32 num_handles = IPC::HandleNumberFromDesc(descriptor); + ASSERT(i + num_handles <= command_size); // TODO(yuriks): Return error + for (u32 j = 0; j < num_handles; ++j) { + Handle handle = src_cmdbuf[i]; + SharedPtr object = src_table.GetGeneric(handle); + ASSERT(object != nullptr); // TODO(yuriks): Return error + if (descriptor == IPC::DescriptorType::MoveHandle) { + src_table.Close(handle); + } + + cmd_buf[i++] = AddOutgoingHandle(std::move(object)); + } + break; + } + case IPC::DescriptorType::CallingPid: { + cmd_buf[i++] = src_process.process_id; + break; + } + default: + UNIMPLEMENTED_MSG("Unsupported handle translation: 0x%08X", descriptor); + } + } + + return RESULT_SUCCESS; +} + +ResultCode HLERequestContext::WriteToOutgoingCommandBuffer(u32_le* dst_cmdbuf, Process& dst_process, + HandleTable& dst_table) const { + IPC::Header header{cmd_buf[0]}; + + size_t untranslated_size = 1u + header.normal_params_size; + size_t command_size = untranslated_size + header.translate_params_size; + ASSERT(command_size <= IPC::COMMAND_BUFFER_LENGTH); + + std::copy_n(cmd_buf.begin(), untranslated_size, dst_cmdbuf); + + size_t i = untranslated_size; + while (i < command_size) { + u32 descriptor = dst_cmdbuf[i] = cmd_buf[i]; + i += 1; + + switch (IPC::GetDescriptorType(descriptor)) { + case IPC::DescriptorType::CopyHandle: + case IPC::DescriptorType::MoveHandle: { + // HLE services don't use handles, so we treat both CopyHandle and MoveHandle equally + u32 num_handles = IPC::HandleNumberFromDesc(descriptor); + ASSERT(i + num_handles <= command_size); + for (u32 j = 0; j < num_handles; ++j) { + SharedPtr object = GetIncomingHandle(cmd_buf[i]); + + // TODO(yuriks): Figure out the proper error handling for if this fails + Handle handle = dst_table.Create(object).Unwrap(); + dst_cmdbuf[i++] = handle; + } + break; + } + default: + UNIMPLEMENTED_MSG("Unsupported handle translation: 0x%08X", descriptor); + } + } + + return RESULT_SUCCESS; } } // namespace Kernel diff --git a/src/core/hle/kernel/hle_ipc.h b/src/core/hle/kernel/hle_ipc.h index f23daa7ea6..d6ebf113c9 100644 --- a/src/core/hle/kernel/hle_ipc.h +++ b/src/core/hle/kernel/hle_ipc.h @@ -8,6 +8,7 @@ #include #include #include "common/common_types.h" +#include "common/swap.h" #include "core/hle/ipc.h" #include "core/hle/kernel/kernel.h" #include "core/hle/kernel/server_session.h" @@ -18,6 +19,9 @@ class ServiceFrameworkBase; namespace Kernel { +class HandleTable; +class Process; + /** * Interface implemented by HLE Session handlers. * This can be provided to a ServerSession in order to hook into several relevant events @@ -62,6 +66,20 @@ protected: * Class containing information about an in-flight IPC request being handled by an HLE service * implementation. Services should avoid using old global APIs (e.g. Kernel::GetCommandBuffer()) and * when possible use the APIs in this class to service the request. + * + * HLE handle protocol + * =================== + * + * To avoid needing HLE services to keep a separate handle table, or having to directly modify the + * requester's table, a tweaked protocol is used to receive and send handles in requests. The kernel + * will decode the incoming handles into object pointers and insert a id in the buffer where the + * handle would normally be. The service then calls GetIncomingHandle() with that id to get the + * pointer to the object. Similarly, instead of inserting a handle into the command buffer, the + * service calls AddOutgoingHandle() and stores the returned id where the handle would normally go. + * + * The end result is similar to just giving services their own real handle tables, but since these + * ids are local to a specific context, it avoids requiring services to manage handles for objects + * across multiple calls and ensuring that unneeded handles are cleaned up. */ class HLERequestContext { public: @@ -80,14 +98,29 @@ public: return session; } - SharedPtr GetIncomingHandle(Handle id_from_cmdbuf) const; - Handle AddOutgoingHandle(SharedPtr object); + /** + * Resolves a object id from the request command buffer into a pointer to an object. See the + * "HLE handle protocol" section in the class documentation for more details. + */ + SharedPtr GetIncomingHandle(u32 id_from_cmdbuf) const; + + /** + * Adds an outgoing object to the response, returning the id which should be used to reference + * it. See the "HLE handle protocol" section in the class documentation for more details. + */ + u32 AddOutgoingHandle(SharedPtr object); private: friend class Service::ServiceFrameworkBase; + ResultCode PopulateFromIncomingCommandBuffer(const u32_le* src_cmdbuf, Process& src_process, + HandleTable& src_table); + ResultCode WriteToOutgoingCommandBuffer(u32_le* dst_cmdbuf, Process& dst_process, + HandleTable& dst_table) const; + std::array cmd_buf; SharedPtr session; + std::vector> request_handles; }; } // namespace Kernel diff --git a/src/core/hle/service/service.cpp b/src/core/hle/service/service.cpp index 35582b0ff5..791a65c19b 100644 --- a/src/core/hle/service/service.cpp +++ b/src/core/hle/service/service.cpp @@ -9,6 +9,7 @@ #include "common/string_util.h" #include "core/hle/ipc.h" #include "core/hle/kernel/client_port.h" +#include "core/hle/kernel/process.h" #include "core/hle/kernel/server_port.h" #include "core/hle/kernel/server_session.h" #include "core/hle/service/ac/ac.h" @@ -172,24 +173,16 @@ void ServiceFrameworkBase::HandleSyncRequest(SharedPtr server_ses // TODO(yuriks): The kernel should be the one handling this as part of translation after // everything else is migrated - IPC::Header request_header{cmd_buf[0]}; - size_t request_size = - 1 + request_header.normal_params_size + request_header.translate_params_size; - ASSERT(request_size <= IPC::COMMAND_BUFFER_LENGTH); // TODO(yuriks): Return error - Kernel::HLERequestContext context; - std::copy_n(cmd_buf, request_size, context.cmd_buf.begin()); context.session = std::move(server_session); + context.PopulateFromIncomingCommandBuffer(cmd_buf, *Kernel::g_current_process, + Kernel::g_handle_table); LOG_TRACE(Service, "%s", MakeFunctionString(info->name, GetServiceName().c_str(), cmd_buf).c_str()); handler_invoker(this, info->handler_callback, context); - - IPC::Header response_header{context.cmd_buf[0]}; - size_t response_size = - 1 + response_header.normal_params_size + response_header.translate_params_size; - ASSERT(response_size <= IPC::COMMAND_BUFFER_LENGTH); - std::copy_n(context.cmd_buf.begin(), response_size, cmd_buf); + context.WriteToOutgoingCommandBuffer(cmd_buf, *Kernel::g_current_process, + Kernel::g_handle_table); } ////////////////////////////////////////////////////////////////////////////////////////////////////