barrier/lib/platform/CMSWindowsRelauncher.cpp

327 lines
8.6 KiB
C++

/*
* synergy-plus -- mouse and keyboard sharing utility
* Copyright (C) 2010 The Synergy+ Project
*
* This package is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* found in the file COPYING that should have accompanied this file.
*
* This package is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "CMSWindowsRelauncher.h"
#include "CThread.h"
#include "TMethodJob.h"
#include "CLog.h"
#include "CArch.h"
#include "Version.h"
#include "CArchDaemonWindows.h"
#include <Tlhelp32.h>
#include <UserEnv.h>
#include <sstream>
CMSWindowsRelauncher::CMSWindowsRelauncher() :
m_thread(NULL)
{
}
CMSWindowsRelauncher::~CMSWindowsRelauncher()
{
delete m_thread;
}
void
CMSWindowsRelauncher::startAsync()
{
m_thread = new CThread(new TMethodJob<CMSWindowsRelauncher>(
this, &CMSWindowsRelauncher::startThread, nullptr));
}
void
CMSWindowsRelauncher::startThread(void*)
{
LOG((CLOG_NOTE "starting relaunch service"));
int ret = relaunchLoop();
// HACK: this actually throws an exception to exit with 0 (nasty)
ARCH->util().app().m_bye(ret);
}
// this still gets the physical session (the one the keyboard and
// mouse is connected to), sometimes this returns -1 but not sure why
DWORD
CMSWindowsRelauncher::getSessionId()
{
return WTSGetActiveConsoleSessionId();
}
BOOL
CMSWindowsRelauncher::winlogonInSession(DWORD sessionId, PHANDLE process)
{
// first we need to take a snapshot of the running processes
HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
if (snapshot == INVALID_HANDLE_VALUE) {
LOG((CLOG_ERR "could not get process snapshot (error: %i)",
GetLastError()));
return 0;
}
PROCESSENTRY32 entry;
entry.dwSize = sizeof(PROCESSENTRY32);
// get the first process, and if we can't do that then it's
// unlikely we can go any further
BOOL gotEntry = Process32First(snapshot, &entry);
if (!gotEntry) {
LOG((CLOG_ERR "could not get first process entry (error: %i)",
GetLastError()));
return 0;
}
// used to record process names for debug info
std::list<std::string> nameList;
// now just iterate until we can find winlogon.exe pid
DWORD pid = 0;
while(gotEntry) {
// make sure we're not checking the system process
if (entry.th32ProcessID != 0) {
DWORD processSessionId;
BOOL pidToSidRet = ProcessIdToSessionId(
entry.th32ProcessID, &processSessionId);
if (!pidToSidRet) {
LOG((CLOG_ERR "could not get session id for process id %i (error: %i)",
entry.th32ProcessID, GetLastError()));
return 0;
}
// only pay attention to processes in the active session
if (processSessionId == sessionId) {
// store the names so we can record them for debug
nameList.push_back(entry.szExeFile);
if (_stricmp(entry.szExeFile, "winlogon.exe") == 0) {
pid = entry.th32ProcessID;
break;
}
}
}
// now move on to the next entry (if we're not at the end)
gotEntry = Process32Next(snapshot, &entry);
if (!gotEntry) {
DWORD err = GetLastError();
if (err != ERROR_NO_MORE_FILES) {
// only worry about error if it's not the end of the snapshot
LOG((CLOG_ERR "could not get subsiquent process entry (error: %i)",
GetLastError()));
return 0;
}
}
}
std::string nameListJoin;
for(std::list<std::string>::iterator it = nameList.begin();
it != nameList.end(); it++) {
nameListJoin.append(*it);
nameListJoin.append(", ");
}
LOG((CLOG_DEBUG "checked processes while looking for winlogon.exe: %s",
nameListJoin.c_str()));
CloseHandle(snapshot);
if (pid) {
// now get the process so we can get the process, with which
// we'll use to get the process token.
*process = OpenProcess(MAXIMUM_ALLOWED, FALSE, pid);
return true;
}
else {
LOG((CLOG_DEBUG "could not find winlogon.exe in session %i", sessionId));
return false;
}
}
// gets the current user (so we can launch under their session)
HANDLE
CMSWindowsRelauncher::getCurrentUserToken(DWORD sessionId, LPSECURITY_ATTRIBUTES security)
{
HANDLE currentToken;
HANDLE winlogonProcess;
if (winlogonInSession(sessionId, &winlogonProcess)) {
LOG((CLOG_DEBUG "session %i has winlogon.exe", sessionId));
// get the token, so we can re-launch with this token
// -- do we really need all these access bits?
BOOL tokenRet = OpenProcessToken(
winlogonProcess,
TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY |
TOKEN_DUPLICATE | TOKEN_ASSIGN_PRIMARY |
TOKEN_ADJUST_SESSIONID | TOKEN_READ | TOKEN_WRITE,
&currentToken);
}
else {
LOG((CLOG_ERR "session %i does not have winlogon.exe "
"which is needed for re-launch", sessionId));
return 0;
}
HANDLE primaryToken;
BOOL duplicateRet = DuplicateTokenEx(
currentToken, MAXIMUM_ALLOWED, security,
SecurityImpersonation, TokenPrimary, &primaryToken);
if (!duplicateRet) {
LOG((CLOG_ERR "could not duplicate token %i (error: %i)",
currentToken, GetLastError()));
return 0;
}
return primaryToken;
}
int
CMSWindowsRelauncher::relaunchLoop()
{
// start with invalid id (gets re-assigned on first loop)
DWORD sessionId = -1;
// keep here so we can check if proc running -- huh?
PROCESS_INFORMATION pi;
ZeroMemory(&pi, sizeof(PROCESS_INFORMATION));
int returnCode = kExitSuccess;
bool launched = false;
// TODO: fix this hack BEFORE release; we need to exit gracefully instead
// of being force killed!
bool loopRunning = true;
while (loopRunning) {
DWORD newSessionId = getSessionId();
// only enter here when id changes, and the session isn't -1, which
// may mean that there is no active session.
if ((newSessionId != sessionId) && (newSessionId != -1)) {
// HACK: doesn't close process in a nice way
// TODO: use CloseMainWindow instead
if (launched) {
TerminateProcess(pi.hProcess, kExitSuccess);
LOG((CLOG_DEBUG "terminated existing process to make way for new one"));
launched = false;
}
// ok, this is now the active session (forget the old one if any)
sessionId = newSessionId;
SECURITY_ATTRIBUTES sa;
ZeroMemory(&sa, sizeof(SECURITY_ATTRIBUTES));
// get the token for the user in active session, which is the
// one receiving input from mouse and keyboard.
HANDLE userToken = getCurrentUserToken(sessionId, &sa);
if (userToken != 0) {
LOG((CLOG_DEBUG "got user token to launch new process"));
std::string cmd = getCommand();
// in case reusing process info struct
ZeroMemory(&pi, sizeof(PROCESS_INFORMATION));
STARTUPINFO si;
ZeroMemory(&si, sizeof(STARTUPINFO));
si.cb = sizeof(STARTUPINFO);
si.lpDesktop = "winsta0\\default";
LPVOID environment;
BOOL blockRet = CreateEnvironmentBlock(&environment, userToken, FALSE);
if (!blockRet) {
LOG((CLOG_ERR "could not create environment block (error: %i)",
GetLastError()));
returnCode = kExitFailed;
loopRunning = false; // stop loop
}
else {
DWORD creationFlags =
NORMAL_PRIORITY_CLASS |
CREATE_NO_WINDOW |
CREATE_UNICODE_ENVIRONMENT;
// re-launch in current active user session
BOOL createRet = CreateProcessAsUser(
userToken, NULL, LPSTR(cmd.c_str()),
&sa, NULL, TRUE, creationFlags,
environment, NULL, &si, &pi);
DestroyEnvironmentBlock(environment);
CloseHandle(userToken);
if (!createRet) {
LOG((CLOG_ERR "could not launch (error: %i)", GetLastError()));
returnCode = kExitFailed;
loopRunning = false;
}
else {
LOG((CLOG_DEBUG "launched in session %i (cmd: %s)",
sessionId, cmd.c_str()));
launched = true;
}
}
}
}
// check for session change every second
ARCH->sleep(1);
}
if (launched) {
// HACK: kill just in case process it has survived somehow
TerminateProcess(pi.hProcess, kExitSuccess);
}
return kExitSuccess;
}
std::string CMSWindowsRelauncher::getCommand()
{
// seems like a fairly convoluted way to get the process name
const char* launchName = ARCH->util().app().argsBase().m_pname;
std::string args = ((CArchDaemonWindows&)ARCH->daemon()).commandLine();
// build up a full command line
std::stringstream cmdTemp;
cmdTemp << launchName << /*" --debug-data session-" << sessionId <<*/ args;
std::string cmd = cmdTemp.str();
size_t i;
std::string find = "--relaunch";
while((i = cmd.find(find)) != std::string::npos) {
cmd.replace(i, find.length(), "");
}
return cmd;
}