// Copyright (c) 2008, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "client/windows/crash_generation/crash_generation_client.h"
#include <cassert>
#include <utility>
#include "client/windows/common/ipc_protocol.h"
namespace google_breakpad {
const int kPipeBusyWaitTimeoutMs = 2000;
#ifdef _DEBUG
const DWORD kWaitForServerTimeoutMs = INFINITE;
#else
const DWORD kWaitForServerTimeoutMs = 15000;
#endif
const int kPipeConnectMaxAttempts = 2;
const DWORD kPipeDesiredAccess = FILE_READ_DATA |
FILE_WRITE_DATA |
FILE_WRITE_ATTRIBUTES;
const DWORD kPipeFlagsAndAttributes = SECURITY_IDENTIFICATION |
SECURITY_SQOS_PRESENT;
const DWORD kPipeMode = PIPE_READMODE_MESSAGE;
const size_t kWaitEventCount = 2;
// This function is orphan for production code. It can be used
// for debugging to help repro some scenarios like the client
// is slow in writing to the pipe after connecting, the client
// is slow in reading from the pipe after writing, etc. The parameter
// overlapped below is not used and it is present to match the signature
// of this function to TransactNamedPipe Win32 API. Uncomment if needed
// for debugging.
/**
static bool TransactNamedPipeDebugHelper(HANDLE pipe,
const void* in_buffer,
DWORD in_size,
void* out_buffer,
DWORD out_size,
DWORD* bytes_count,
LPOVERLAPPED) {
// Uncomment the next sleep to create a gap before writing
// to pipe.
// Sleep(5000);
if (!WriteFile(pipe,
in_buffer,
in_size,
bytes_count,
NULL)) {
return false;
}
// Uncomment the next sleep to create a gap between write
// and read.
// Sleep(5000);
return ReadFile(pipe, out_buffer, out_size, bytes_count, NULL) != FALSE;
}
**/
CrashGenerationClient::CrashGenerationClient(
const wchar_t* pipe_name,
MINIDUMP_TYPE dump_type,
const CustomClientInfo* custom_info)
: pipe_name_(pipe_name),
pipe_handle_(NULL),
dump_type_(dump_type),
thread_id_(0),
server_process_id_(0),
crash_event_(NULL),
crash_generated_(NULL),
server_alive_(NULL),
exception_pointers_(NULL),
custom_info_() {
memset(&assert_info_, 0, sizeof(assert_info_));
if (custom_info) {
custom_info_ = *custom_info;
}
}
CrashGenerationClient::CrashGenerationClient(
HANDLE pipe_handle,
MINIDUMP_TYPE dump_type,
const CustomClientInfo* custom_info)
: pipe_name_(),
pipe_handle_(pipe_handle),
dump_type_(dump_type),
thread_id_(0),
server_process_id_(0),
crash_event_(NULL),
crash_generated_(NULL),
server_alive_(NULL),
exception_pointers_(NULL),
custom_info_() {
memset(&assert_info_, 0, sizeof(assert_info_));
if (custom_info) {
custom_info_ = *custom_info;
}
}
CrashGenerationClient::~CrashGenerationClient() {
if (crash_event_) {
CloseHandle(crash_event_);
}
if (crash_generated_) {
CloseHandle(crash_generated_);
}
if (server_alive_) {
CloseHandle(server_alive_);
}
}
// Performs the registration step with the server process.
// The registration step involves communicating with the server
// via a named pipe. The client sends the following pieces of
// data to the server:
//
// * Message tag indicating the client is requesting registration.
// * Process id of the client process.
// * Address of a DWORD variable in the client address space
// that will contain the thread id of the client thread that
// caused the crash.
// * Address of a EXCEPTION_POINTERS* variable in the client
// address space that will point to an instance of EXCEPTION_POINTERS
// when the crash happens.
// * Address of an instance of MDRawAssertionInfo that will contain
// relevant information in case of non-exception crashes like assertion
// failures and pure calls.
//
// In return the client expects the following information from the server:
//
// * Message tag indicating successful registration.
// * Server process id.
// * Handle to an object that client can signal to request dump
// generation from the server.
// * Handle to an object that client can wait on after requesting
// dump generation for the server to finish dump generation.
// * Handle to a mutex object that client can wait on to make sure
// server is still alive.
//
// If any step of the expected behavior mentioned above fails, the
// registration step is not considered successful and hence out-of-process
// dump generation service is not available.
//
// Returns true if the registration is successful; false otherwise.
bool CrashGenerationClient::Register() {
if (IsRegistered()) {
return true;
}
HANDLE pipe = ConnectToServer();
if (!pipe) {
return false;
}
bool success = RegisterClient(pipe);
CloseHandle(pipe);
return success;
}
bool CrashGenerationClient::RequestUpload(DWORD crash_id) {
HANDLE pipe = ConnectToServer();
if (!pipe) {
return false;
}
CustomClientInfo custom_info = {NULL, 0};
ProtocolMessage msg(MESSAGE_TAG_UPLOAD_REQUEST, crash_id,
static_cast<MINIDUMP_TYPE>(NULL), NULL, NULL, NULL,
custom_info, NULL, NULL, NULL);
DWORD bytes_count = 0;
bool success = WriteFile(pipe, &msg, sizeof(msg), &bytes_count, NULL) != 0;
CloseHandle(pipe);
return success;
}
HANDLE CrashGenerationClient::ConnectToServer() {
HANDLE pipe = ConnectToPipe(pipe_name_.c_str(),
kPipeDesiredAccess,
kPipeFlagsAndAttributes);
if (!pipe) {
return NULL;
}
DWORD mode = kPipeMode;
if (!SetNamedPipeHandleState(pipe, &mode, NULL, NULL)) {
CloseHandle(pipe);
pipe = NULL;
}
return pipe;
}
bool CrashGenerationClient::RegisterClient(HANDLE pipe) {
ProtocolMessage msg(MESSAGE_TAG_REGISTRATION_REQUEST,
GetCurrentProcessId(),
dump_type_,
&thread_id_,
&exception_pointers_,
&assert_info_,
custom_info_,
NULL,
NULL,
NULL);
ProtocolMessage reply;
DWORD bytes_count = 0;
// The call to TransactNamedPipe below can be changed to a call
// to TransactNamedPipeDebugHelper to help repro some scenarios.
// For details see comments for TransactNamedPipeDebugHelper.
if (!TransactNamedPipe(pipe,
&msg,
sizeof(msg),
&reply,
sizeof(ProtocolMessage),
&bytes_count,
NULL)) {
return false;
}
if (!ValidateResponse(reply)) {
return false;
}
ProtocolMessage ack_msg;
ack_msg.tag = MESSAGE_TAG_REGISTRATION_ACK;
if (!WriteFile(pipe, &ack_msg, sizeof(ack_msg), &bytes_count, NULL)) {
return false;
}
crash_event_ = reply.dump_request_handle;
crash_generated_ = reply.dump_generated_handle;
server_alive_ = reply.server_alive_handle;
server_process_id_ = reply.id;
return true;
}
HANDLE CrashGenerationClient::ConnectToPipe(const wchar_t* pipe_name,
DWORD pipe_access,
DWORD flags_attrs) {
if (pipe_handle_) {
HANDLE t = pipe_handle_;
pipe_handle_ = NULL;
return t;
}
for (int i = 0; i < kPipeConnectMaxAttempts; ++i) {
HANDLE pipe = CreateFile(pipe_name,
pipe_access,
0,
NULL,
OPEN_EXISTING,
flags_attrs,
NULL);
if (pipe != INVALID_HANDLE_VALUE) {
return pipe;
}
// Cannot continue retrying if error is something other than
// ERROR_PIPE_BUSY.
if (GetLastError() != ERROR_PIPE_BUSY) {
break;
}
// Cannot continue retrying if wait on pipe fails.
if (!WaitNamedPipe(pipe_name, kPipeBusyWaitTimeoutMs)) {
break;
}
}
return NULL;
}
bool CrashGenerationClient::ValidateResponse(
const ProtocolMessage& msg) const {
return (msg.tag == MESSAGE_TAG_REGISTRATION_RESPONSE) &&
(msg.id != 0) &&
(msg.dump_request_handle != NULL) &&
(msg.dump_generated_handle != NULL) &&
(msg.server_alive_handle != NULL);
}
bool CrashGenerationClient::IsRegistered() const {
return crash_event_ != NULL;
}
bool CrashGenerationClient::RequestDump(EXCEPTION_POINTERS* ex_info,
MDRawAssertionInfo* assert_info) {
if (!IsRegistered()) {
return false;
}
exception_pointers_ = ex_info;
thread_id_ = GetCurrentThreadId();
if (assert_info) {
memcpy(&assert_info_, assert_info, sizeof(assert_info_));
} else {
memset(&assert_info_, 0, sizeof(assert_info_));
}
return SignalCrashEventAndWait();
}
bool CrashGenerationClient::RequestDump(EXCEPTION_POINTERS* ex_info) {
return RequestDump(ex_info, NULL);
}
bool CrashGenerationClient::RequestDump(MDRawAssertionInfo* assert_info) {
return RequestDump(NULL, assert_info);
}
bool CrashGenerationClient::SignalCrashEventAndWait() {
assert(crash_event_);
assert(crash_generated_);
assert(server_alive_);
// Reset the dump generated event before signaling the crash
// event so that the server can set the dump generated event
// once it is done generating the event.
if (!ResetEvent(crash_generated_)) {
return false;
}
if (!SetEvent(crash_event_)) {
return false;
}
HANDLE wait_handles[kWaitEventCount] = {crash_generated_, server_alive_};
DWORD result = WaitForMultipleObjects(kWaitEventCount,
wait_handles,
FALSE,
kWaitForServerTimeoutMs);
// Crash dump was successfully generated only if the server
// signaled the crash generated event.
return result == WAIT_OBJECT_0;
}
HANDLE CrashGenerationClient::DuplicatePipeToClientProcess(const wchar_t* pipe_name,
HANDLE hProcess) {
for (int i = 0; i < kPipeConnectMaxAttempts; ++i) {
HANDLE local_pipe = CreateFile(pipe_name, kPipeDesiredAccess,
0, NULL, OPEN_EXISTING,
kPipeFlagsAndAttributes, NULL);
if (local_pipe != INVALID_HANDLE_VALUE) {
HANDLE remotePipe = INVALID_HANDLE_VALUE;
if (DuplicateHandle(GetCurrentProcess(), local_pipe,
hProcess, &remotePipe, 0, FALSE,
DUPLICATE_CLOSE_SOURCE | DUPLICATE_SAME_ACCESS)) {
return remotePipe;
} else {
return INVALID_HANDLE_VALUE;
}
}
// Cannot continue retrying if the error wasn't a busy pipe.
if (GetLastError() != ERROR_PIPE_BUSY) {
return INVALID_HANDLE_VALUE;
}
if (!WaitNamedPipe(pipe_name, kPipeBusyWaitTimeoutMs)) {
return INVALID_HANDLE_VALUE;
}
}
return INVALID_HANDLE_VALUE;
}
} // namespace google_breakpad