I want to execute a C++ Program with my PHP Back-end. The C++ Program is responsible for removing usb devices like usb sticks from my PC. When I open the program (which is on a separate local drive) with the CLI without administrative rights, the program starts and finishes the job correctly.
When I start the program with PHP using exec("/path/to/my/program.exe and-parameters") which is literally the same way as from the CLI, the program just starts and returns "failed" so something is different when using the CLI.
The C++ Code:
//
// RemoveDriveByLetter.cpp by Uwe Sieber - www.uwe-sieber.de
//
// Simple demonstration how to prepare a disk drive for save removal
//
// Works with removable and fixed drives under W2K, XP, W2K3, Vista
//
// Console application - expects the drive letter of the drive to remove as parameter
//
// you are free to use this code in your projects
//
#include "stdafx.h"
#include <stdio.h>
#include <windows.h>
#include <Setupapi.h>
#include <winioctl.h>
#include <winioctl.h>
#include <cfgmgr32.h>
#include <string>
//-------------------------------------------------
DEVINST GetDrivesDevInstByDeviceNumber(long DeviceNumber, UINT DriveType, char* szDosDeviceName);
//-------------------------------------------------
//-------------------------------------------------
int main(int argc, char* argv[])
{
/*if ( argc != 2 ) {
return 1;
}*/
char DriveLetter = argv[1][0];
DriveLetter &= ~0x20; // uppercase
if ( DriveLetter < 'A' || DriveLetter > 'Z' ) {
return 1;
}
std::string path = "";
path += DriveLetter;
path.append(":\\");
printf(path.c_str());
char szRootPath[sizeof(path)] ="";
strncpy(szRootPath, path.c_str(), sizeof(path));
std::string device = "";
device += DriveLetter;
device.append(":");
printf(device.c_str());
char szDevicePath[sizeof(device)] = "";
strncpy(szDevicePath, device.c_str(), sizeof(device));
std::string accesspath = "";
accesspath += "\\\\.\\";
accesspath += device;
printf(accesspath.c_str());
char szVolumeAccessPath[sizeof(accesspath)] = ""; // "\\.\X:" -> to open the volume
strncpy(szVolumeAccessPath, accesspath.c_str(), sizeof(accesspath));
long DeviceNumber = -1;
// open the storage volume
HANDLE hVolume = CreateFile(szVolumeAccessPath, 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, NULL, NULL);
if (hVolume == INVALID_HANDLE_VALUE) {
return 1;
}
// get the volume's device number
STORAGE_DEVICE_NUMBER sdn;
DWORD dwBytesReturned = 0;
long res = DeviceIoControl(hVolume, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL, 0, &sdn, sizeof(sdn), &dwBytesReturned, NULL);
if ( res ) {
DeviceNumber = sdn.DeviceNumber;
}
CloseHandle(hVolume);
if ( DeviceNumber == -1 ) {
return 1;
}
// get the drive type which is required to match the device numbers correctely
UINT DriveType = GetDriveType(szRootPath);
// get the dos device name (like \device\floppy0) to decide if it's a floppy or not - who knows a better way?
char szDosDeviceName[MAX_PATH];
res = QueryDosDevice(szDevicePath, szDosDeviceName, MAX_PATH);
if ( !res ) {
return 1;
}
// get the device instance handle of the storage volume by means of a SetupDi enum and matching the device number
DEVINST DevInst = GetDrivesDevInstByDeviceNumber(DeviceNumber, DriveType, szDosDeviceName);
if ( DevInst == 0 ) {
return 1;
}
PNP_VETO_TYPE VetoType = PNP_VetoTypeUnknown;
WCHAR VetoNameW[MAX_PATH];
VetoNameW[0] = 0;
bool bSuccess = false;
// get drives's parent, e.g. the USB bridge, the SATA port, an IDE channel with two drives!
DEVINST DevInstParent = 0;
res = CM_Get_Parent(&DevInstParent, DevInst, 0);
for ( long tries=1; tries<=3; tries++ ) { // sometimes we need some tries...
VetoNameW[0] = 0;
// CM_Query_And_Remove_SubTree doesn't work for restricted users
//res = CM_Query_And_Remove_SubTreeW(DevInstParent, &VetoType, VetoNameW, MAX_PATH, CM_REMOVE_NO_RESTART); // CM_Query_And_Remove_SubTreeA is not implemented under W2K!
//res = CM_Query_And_Remove_SubTreeW(DevInstParent, NULL, NULL, 0, CM_REMOVE_NO_RESTART); // with messagebox (W2K, Vista) or balloon (XP)
res = CM_Request_Device_EjectW(DevInstParent, &VetoType, VetoNameW, MAX_PATH, 0);
//res = CM_Request_Device_EjectW(DevInstParent, NULL, NULL, 0, 0); // with messagebox (W2K, Vista) or balloon (XP)
bSuccess = (res==CR_SUCCESS && VetoType==PNP_VetoTypeUnknown);
if ( bSuccess ) {
break;
}
Sleep(500); // required to give the next tries a chance!
}
if ( bSuccess ) {
printf("Success
");
return 0;
}
printf("failed
");
printf("Result=0x%2X
", res);
if ( VetoNameW[0] ) {
printf("VetoName=%ws)
", VetoNameW);
}
return 1;
}
//-----------------------------------------------------------
char* appendCharToCharArray(char* array, char a)
{
size_t len = strlen(array);
char* ret = new char[len+2];
strcpy(ret, array);
ret[len] = a;
ret[len+1] = '\0';
return ret;
}
//----------------------------------------------------------------------
// returns the device instance handle of a storage volume or 0 on error
//----------------------------------------------------------------------
DEVINST GetDrivesDevInstByDeviceNumber(long DeviceNumber, UINT DriveType, char* szDosDeviceName)
{
bool IsFloppy = (strstr(szDosDeviceName, "\\Floppy") != NULL); // who knows a better way?
GUID* guid;
switch (DriveType) {
case DRIVE_REMOVABLE:
if ( IsFloppy ) {
guid = (GUID*)&GUID_DEVINTERFACE_FLOPPY;
} else {
guid = (GUID*)&GUID_DEVINTERFACE_DISK;
}
break;
case DRIVE_FIXED:
guid = (GUID*)&GUID_DEVINTERFACE_DISK;
break;
case DRIVE_CDROM:
guid = (GUID*)&GUID_DEVINTERFACE_CDROM;
break;
default:
return 0;
}
// Get device interface info set handle for all devices attached to system
HDEVINFO hDevInfo = SetupDiGetClassDevs(guid, NULL, NULL, DIGCF_PRESENT | DIGCF_DEVICEINTERFACE);
if (hDevInfo == INVALID_HANDLE_VALUE) {
return 0;
}
// Retrieve a context structure for a device interface of a device information set
DWORD dwIndex = 0;
long res;
BYTE Buf[1024];
PSP_DEVICE_INTERFACE_DETAIL_DATA pspdidd = (PSP_DEVICE_INTERFACE_DETAIL_DATA)Buf;
SP_DEVICE_INTERFACE_DATA spdid;
SP_DEVINFO_DATA spdd;
DWORD dwSize;
spdid.cbSize = sizeof(spdid);
while ( true ) {
res = SetupDiEnumDeviceInterfaces(hDevInfo, NULL, guid, dwIndex, &spdid);
if ( !res ) {
break;
}
dwSize = 0;
SetupDiGetDeviceInterfaceDetail(hDevInfo, &spdid, NULL, 0, &dwSize, NULL); // check the buffer size
if ( dwSize!=0 && dwSize<=sizeof(Buf) ) {
pspdidd->cbSize = sizeof(*pspdidd); // 5 Bytes!
ZeroMemory(&spdd, sizeof(spdd));
spdd.cbSize = sizeof(spdd);
long res = SetupDiGetDeviceInterfaceDetail(hDevInfo, &spdid, pspdidd, dwSize, &dwSize, &spdd);
if ( res ) {
// in case you are interested in the USB serial number:
// the device id string contains the serial number if the device has one,
// otherwise a generated id that contains the '&' char...
/*
DEVINST DevInstParent = 0;
CM_Get_Parent(&DevInstParent, spdd.DevInst, 0);
char szDeviceIdString[MAX_PATH];
CM_Get_Device_ID(DevInstParent, szDeviceIdString, MAX_PATH, 0);
printf("DeviceId=%s
", szDeviceIdString);
*/
// open the disk or cdrom or floppy
HANDLE hDrive = CreateFile(pspdidd->DevicePath, 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
if ( hDrive != INVALID_HANDLE_VALUE ) {
// get its device number
STORAGE_DEVICE_NUMBER sdn;
DWORD dwBytesReturned = 0;
res = DeviceIoControl(hDrive, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL, 0, &sdn, sizeof(sdn), &dwBytesReturned, NULL);
if ( res ) {
if ( DeviceNumber == (long)sdn.DeviceNumber ) { // match the given device number with the one of the current device
CloseHandle(hDrive);
SetupDiDestroyDeviceInfoList(hDevInfo);
return spdd.DevInst;
}
}
CloseHandle(hDrive);
}
}
}
dwIndex++;
}
SetupDiDestroyDeviceInfoList(hDevInfo);
return 0;
}
//-----------------------------------------------------------
The program returns:
array(2) ( [0] => (string) D:\D:\.\D:failed [1] => (string) Result=0x33 )
Somebody a suggestion?
If you are running PHP in safe mode then only files in the safe_mode_exec_dir will be allowed to run.
It appears you are running in the Windows environment. You may want to consider executing this using the Windows shell which gives you more control over your external executing programs, and may return additional information if it fails and help diagnosing what the underlying issue is with the exec() function.
Comments from the online PHP manual are:
start Notepad.exe minimized in the background:
<?php
$WshShell = new COM("WScript.Shell");
$oExec = $WshShell->Run("notepad.exe", 7, false);
?>
start a shell command invisible in the background:
<?php
$WshShell = new COM("WScript.Shell");
$oExec = $WshShell->Run("cmd /C dir /S %windir%", 0, false);
?>
start MSPaint maximized and wait for you to close it before continuing the script:
<?php
$WshShell = new COM("WScript.Shell");
$oExec = $WshShell->Run("mspaint.exe", 3, true);
?>
For more info on the Run() method go to: https://msdn.microsoft.com/en-us/subscriptions/d5fk67ky(v=vs.84).aspx
First run the command through the php client (from shell).
<?php
exec("/path/to/my/program.exe and-parameters");
.
$ php.exe -f file.php //Check link above. I am used to Linux and you might need diffrent params
If that works, then it is most likely an iis permission problem.
This article describes how to set up an application pool and associate it with your PHP service. Once that is done, right-click on the application pool you created and select "Advanced Settings". Under the "Process Model" heading, you will see a setting named "Identity"; change the value to an account that has the permissions you seek (such as "Local System" or "Local Service").
The identity of the default application pool (under which your PHP service is currently running) is not powerful enough for your purposes!