Thread: crc32

Soory for offtopic but how can you end a process called Gunz.exe?
i thought it was TerminateProcess("Gunz.exe", 0); but that doesn't work..

You probably can kill it if:
1. It's owned by the same user.
2. You know which process-ID the process is.

You will not be able to just say "terminate a process called xxx.exe", but if you have the process id (HANDLE) of the process, you can use

Code:

TerminateProcess(hProcess, exitCode);

Now, your next question is how do you find the process-id. One way to do that is to use another process to CREATE your actual process, as well as creating YOUR process, and then pass the process handle from the create-process to your process.

I'm sure there is a way to list the currently running processes (TaskManager can do it), but I don't know what API call that is, and it's fairly normal to have a "management process" if you want to do this sort of thing anyways.

--
Mats

Got it XD

Code:

DWORD dwProcessId;
HWND hFind;
HANDLE hProcess;

do
{
	hFind=FindWindow("RealSpace2",Gunz);
	if (!hFind)
		break;
	GetWindowThreadProcessId(hFind,&dwProcessId);
	hProcess=OpenProcess(PROCESS_TERMINATE,NULL, dwProcessId);
	if (hProcess)
		TerminateProcess(hProcess,0);
}

How could i make the crc of the memory now?
I want it from adress 00401000 to 005C5FFF

Try using

Code:

BOOL ReadProcessMemory(
  HANDLE hProcess,              // handle to the process
  LPCVOID lpBaseAddress,        // base of memory area
  LPVOID lpBuffer,              // data buffer
  SIZE_T nSize,                 // number of bytes to read
  SIZE_T * lpNumberOfBytesRead  // number of bytes read
);

Any process that has a handle with PROCESS_VM_READ access can call the function.

--
Mats

Originally Posted by matsp

Try using

Code:

BOOL ReadProcessMemory(
  HANDLE hProcess,              // handle to the process
  LPCVOID lpBaseAddress,        // base of memory area
  LPVOID lpBuffer,              // data buffer
  SIZE_T nSize,                 // number of bytes to read
  SIZE_T * lpNumberOfBytesRead  // number of bytes read
);

Any process that has a handle with PROCESS_VM_READ access can call the function.

--
Mats

How would i use that?

Code:

ReadProcessMemory(hProcess, 0x0040100, ???, 0x1C4FFF, ???);

Perhaps something like this (code isn't complete, nor have I verified that it compiles, but it should give you the right idea):

Code:

BOOL result;
unsigned char buffer[4096];
unsigned int crc;
SIZE_T nread;

while (address < end_address) {
   result = ReadProcessMemory(handle, (LPCVOID)address, buffer, sizeof buffer, &nread);
   if (result) {
      for(i = 0; i < nread; i++) {
         ... update CRC based on buffer[i]
      }
   } 
   address += sizeof buffer;
}

--
Mats

I made this of it:

Code:

#include "StdAfx.h"
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
DWORD dwProcessId;
HWND hFind;
HANDLE hProcess;

void _main(){
hFind=FindWindow("RealSpace2", "Gunz");
GetWindowThreadProcessId(hFind,&dwProcessId);
hProcess=OpenProcess(PROCESS_TERMINATE,NULL, dwProcessId);
BOOL result;
unsigned char buffer[4096];
unsigned int crc;
SIZE_T nread;
unsigned long table[256] = {
	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
	0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
	0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
	0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
	0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
	0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
	0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
	0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
	0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
	0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
	0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
	0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
	0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
	0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
	0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
	0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
	0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
	0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
	0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d};

	register unsigned long iCRC;
	register long i = 0;

while (0x0040100 < 0x005C5FFF) {
   result = ReadProcessMemory(hProcess, (LPCVOID)0x0040100, buffer, sizeof buffer, &nread);
   if (result) {
	  for (i = 0; i < nread; i++){
				iCRC = ((iCRC >> 8) & 0xFFFFFFFF) ^ table[(iCRC ^ fgetc(hProcess)) & 0xFF];
				printf("CRC32: %x", (iCRC ^ 0xFFFFFFFF));
	  }
   } 
   0x0040100 += sizeof buffer;
}
}

Errors:

Code:

CRC32.cpp
C:\Program Files\Microsoft Visual Studio\MyProjects\CRC32\CRC32.cpp(69) : warning C4018: '<' : signed/unsigned mismatch
C:\Program Files\Microsoft Visual Studio\MyProjects\CRC32\CRC32.cpp(70) : error C2664: 'fgetc' : cannot convert parameter 1 from 'void *' to 'struct _iobuf *'
        Conversion from 'void*' to pointer to non-'void' requires an explicit cast
C:\Program Files\Microsoft Visual Studio\MyProjects\CRC32\CRC32.cpp(74) : error C2106: '+=' : left operand must be l-value
Error executing cl.exe.

How do i fix those?

SIZE_T is an unsigned, so maybe "i" should be too?

I'm pretty sure I said "address" in my example, not "0x00400100" - one of those is a constant number, the other is a variable. No prize for guessing which is which.

You are using "fgetc()" in the loop - that's not what you want to do. You need to use the data you got from the ReadProcessMemory.

--
Mats