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//
// detour 4F77B2 to mymemcheck2
//
int *extern_array = 0x5C26D0;
int __cdecl mymemcheck2(unsigned char *buffer, int count, struct mckey key);
#define first 0x4F7820
#define second 0x4F7858
// TITLE orig.asm
// .386P
//
//EXTRN _extern_array:DWORD
//
//_TEXT SEGMENT
//
//getret PROC NEAR
// mov eax,dword ptr [esp]
// ret
//getret ENDP
//
//PUBLIC _memcheck2
int __cdecl mymemcheck2(unsigned char *buffer, int count, struct mckey key)
{
unsigned int x, i, j;
unsigned int ecx, ebx, edx, eax;
if (!extern_array) {
}
//_memcheck2 PROC NEAR
// push ebp
// mov ebp,esp
// mov al,byte ptr [ebp+10h]
// push ebx
// not al
// movzx eax,al
eax = ~key.a[0] & 0xff;
// movzx edx,byte ptr [ebp+11h]
edx = key.a[1] & 0xff;
// mov eax,dword ptr [eax*4+_extern_array]
eax = extern_array[eax];
// push esi
// mov esi,0FFFFFFh
// push edi
// xor eax,esi
eax ^= 0xffffff;
// mov edi,0FFh
// mov ecx,eax
// and ecx,edi
ecx = eax & 0xff;
// xor ecx,edx
ecx ^= edx;
// movzx edx,byte ptr [ebp+12h]
edx = key.a[2] & 0xff;
// mov ecx,dword ptr [ecx*4+_extern_array]
ecx = extern_array[ecx];
// sar eax,8
// and eax,esi
eax = ((int)eax>>8) & 0xffffff;
// xor ecx,eax
ecx ^= eax;
// mov eax,ecx
// and eax,edi
// xor eax,edx
eax = (ecx & 0xff) ^ edx;
// movzx edx,byte ptr [ebp+13h]
edx = key.a[3] & 0xff;
// mov eax,dword ptr [eax*4+_extern_array]
eax = extern_array[eax];
// sar ecx,8
// and ecx,esi
ecx = ((int)ecx>>8) & 0xffffff;
// xor eax,ecx
eax ^= ecx;
// mov ecx,eax
// and ecx,edi
// xor ecx,edx
ecx = (eax & 0xff) ^ edx;
// sar eax,8
eax = ((int)eax>>8) & 0xffffff;
// mov ebx,dword ptr [ecx*4+_extern_array]
// and eax,esi
ebx = extern_array[ecx];
// xor ebx,eax
ebx ^= eax;
ebx ^= first;
// call getret
// mov ecx,dword ptr [ebp+0Ch]
// xor ebx,eax
// mov eax,dword ptr [ebp+8]
// add ecx,eax
// mov dword ptr [ebp+10h],eax
// cmp eax,ecx
if (count == 0) goto done;
// jae done
//myloop:
// mov edx,dword ptr [ebp+10h]
// mov eax,ebx
// and eax,edi
// movzx edx,byte ptr [edx]
// xor eax,edx
// sar ebx,8
// mov eax,dword ptr [eax*4+_extern_array]
//
// and ebx,esi
// xor ebx,eax
// inc dword ptr [ebp+10h]
// cmp dword ptr [ebp+10h],ecx
// jb myloop
for (i=0;i<(unsigned int)count;i++) {
unsigned char tmp = buffer[i];
eax = (int) tmp ^ (ebx & 0xff);
ebx = ((int)ebx >> 8) & 0xffffff;
eax = extern_array[eax];
ebx ^= eax;
}
//done:
done:
// call getret
eax = second;
eax ^= ~ebx;
return eax;
// not ebx
// pop edi
// xor eax,ebx
// pop esi
// pop ebx
// pop ebp
// ret
//_memcheck2 ENDP
//_TEXT ENDS
//END
}
Oh well, maybe they won't patch eqgame.exe... One can hope...