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// Copyright (c) 2013 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 "sandbox/win/src/named_pipe_dispatcher.h"
#include "base/basictypes.h"
#include "base/strings/string_split.h"
#include "sandbox/win/src/crosscall_client.h"
#include "sandbox/win/src/interception.h"
#include "sandbox/win/src/interceptors.h"
#include "sandbox/win/src/ipc_tags.h"
#include "sandbox/win/src/named_pipe_interception.h"
#include "sandbox/win/src/named_pipe_policy.h"
#include "sandbox/win/src/policy_broker.h"
#include "sandbox/win/src/policy_params.h"
#include "sandbox/win/src/sandbox.h"
namespace sandbox {
NamedPipeDispatcher::NamedPipeDispatcher(PolicyBase* policy_base)
: policy_base_(policy_base) {
static const IPCCall create_params = {
{IPC_CREATENAMEDPIPEW_TAG,
{WCHAR_TYPE,
UINT32_TYPE,
UINT32_TYPE,
UINT32_TYPE,
UINT32_TYPE,
UINT32_TYPE,
UINT32_TYPE}},
reinterpret_cast<CallbackGeneric>(&NamedPipeDispatcher::CreateNamedPipe)};
ipc_calls_.push_back(create_params);
}
bool NamedPipeDispatcher::SetupService(InterceptionManager* manager,
int service) {
if (IPC_CREATENAMEDPIPEW_TAG == service)
return INTERCEPT_EAT(manager, kKerneldllName, CreateNamedPipeW,
CREATE_NAMED_PIPE_ID, 36);
return false;
}
bool NamedPipeDispatcher::CreateNamedPipe(IPCInfo* ipc,
base::string16* name,
uint32 open_mode,
uint32 pipe_mode,
uint32 max_instances,
uint32 out_buffer_size,
uint32 in_buffer_size,
uint32 default_timeout) {
ipc->return_info.win32_result = ERROR_ACCESS_DENIED;
ipc->return_info.handle = INVALID_HANDLE_VALUE;
std::vector<base::string16> paths;
std::vector<base::string16> innerpaths;
base::SplitString(*name, '/', &paths);
for (std::vector<base::string16>::const_iterator iter = paths.begin();
iter != paths.end(); ++iter) {
base::SplitString(*iter, '\\', &innerpaths);
for (std::vector<base::string16>::const_iterator iter2 = innerpaths.begin();
iter2 != innerpaths.end(); ++iter2) {
if (*iter2 == L"..")
return true;
}
}
const wchar_t* pipe_name = name->c_str();
CountedParameterSet<NameBased> params;
params[NameBased::NAME] = ParamPickerMake(pipe_name);
EvalResult eval = policy_base_->EvalPolicy(IPC_CREATENAMEDPIPEW_TAG,
params.GetBase());
// "For file I/O, the "\\?\" prefix to a path string tells the Windows APIs to
// disable all string parsing and to send the string that follows it straight
// to the file system."
// http://msdn.microsoft.com/en-us/library/aa365247(VS.85).aspx
// This ensures even if there is a path traversal in the pipe name, and it is
// able to get past the checks above, it will still not be allowed to escape
// our whitelisted namespace.
if (name->compare(0, 4, L"\\\\.\\") == 0)
name->replace(0, 4, L"\\\\\?\\");
HANDLE pipe;
DWORD ret = NamedPipePolicy::CreateNamedPipeAction(eval, *ipc->client_info,
*name, open_mode,
pipe_mode, max_instances,
out_buffer_size,
in_buffer_size,
default_timeout, &pipe);
ipc->return_info.win32_result = ret;
ipc->return_info.handle = pipe;
return true;
}
} // namespace sandbox
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