//标志减7就是函数头
BYTE DecodeFlag[16] = {0x8B, 0xFA, 0x83, 0xC9, 0xFF, 0x33, 0xC0, 0x33, 0xF6, 0xF2, 0xAE, 0xF7, 0xD1, 0x49, 0x8B, 0xE9};
//搜索数据
BYTE* SearchData(BYTE* dataall,int alllen,BYTE* data,int len)
{
for(int i = 0; i < alllen; i++)
{
if( !memcmp(dataall+i,data,len) )
return dataall+i;
}
return NULL;
}
HANDLE handle;
DWORD VirtualBaseAddr;
DWORD FuncAddr;
BYTE reg_al;
BYTE reg_bl;
BYTE reg_cl;
BYTE reg_dl;
//list<t_disasm> dalist;
CLink dalist;
void Write(char* data)
{
SetFilePointer(handle,0,NULL,FILE_END);
int filelen = strlen(data);
data[filelen++] = '\r';
data[filelen++] = '\n';
DWORD dw;
WriteFile(handle,data,filelen,&dw,NULL);
dw = GetLastError();
}
static char espdata[0x1000000];
static DWORD espdataaddr;
static DWORD tmpesp;
static DWORD codeaddr;
static DWORD endesp;//ESP尾步
static BYTE gotoretcode[5] = {0xE9,0x00,0x00,0x00,0x00};
static DWORD dwoffset = 0;
char *codedata = new char[102400];
//执行代码
void ExecuteCode(BYTE* code,int len)
{
memset(espdata,0,0x1000000);
static DWORD dw;
VirtualProtect(espdata,0x1000000,PAGE_READWRITE | PAGE_EXECUTE,&dw);
espdataaddr = (DWORD)espdata + 0x0500000;
codeaddr = (DWORD)code;
//__asm _emit 0xCC
_asm
{
pushad
mov eax,_Exec_End
sub eax,codeaddr
sub eax,len
sub eax,5
mov dwoffset,eax
popad
}
*(DWORD*)&gotoretcode[1] = dwoffset;
memcpy(code+len,gotoretcode,5);
_asm
{
pushad
mov tmpesp,esp
mov esp,espdataaddr
mov al,reg_al
mov bl,reg_bl
mov cl,reg_cl
mov dl,reg_dl
jmp codeaddr
_Exec_End:
mov endesp,esp
mov esp,tmpesp
popad
}
static char* data;
data = (char*)*(DWORD*)endesp;
Write(data);
}
void InsetList(t_disasm *da)
{
//dalist.push_back(*da);
t_disasm* t_da = new t_disasm;
if( !t_da )
{
MsgBox("错误!");
return;
}
memcpy(t_da,da,sizeof(t_disasm));
dalist.AddTail(t_da);
}
void ClearList()
{
dalist.RemoveAll();
}
//识别代码
void IdentifyCode(t_disasm *da)
{
if( !strcmp(da->vm_name,"VMOV_REG08_IMM32") )
{
switch(da->reg[0])
{
case REG_EAX:
reg_al = da->immconst;
break;
case REG_EBX:
reg_bl = da->immconst;
case REG_ECX:
reg_bl = da->immconst;
case REG_EDX:
reg_dl = da->immconst;
}
}
if( !strcmp(da->vm_name,"VXOR_REG08_REG08") )
{
switch(da->reg[0])
{
case REG_EAX:
reg_al = 0;
break;
case REG_EBX:
reg_bl = 0;
case REG_ECX:
reg_bl = 0;
case REG_EDX:
reg_dl = 0;
}
}
if( da->cmdtype == C_CAL )//如果是CALL
{
if( da->jmpconst == FuncAddr )//如果是调用解密函数
{
memset(codedata,0,102400);
char* pcode = codedata;
//list<t_disasm>::iterator itr = dalist.begin();
//for(itr = dalist.begin(); itr != dalist.end(); ++itr)
//{
// t_disasm t_da = *itr;
// memcpy(pcode,t_da.hexcode,t_da.codelen);
// pcode += t_da.codelen;
//}
T_Link* link = dalist.GetLink();
while(link)
{
t_disasm* t_da = (t_disasm*)link->data;
memcpy(pcode,t_da->hexcode,t_da->codelen);
pcode += t_da->codelen;
link = dalist.GetNext();
}
char calltext[16];
t_asmmodel t_asm;
sprintf(calltext,"call %08X",(DWORD)Uncode);
char errtext[255];
int len = Assemble(calltext,(ulong)pcode,&t_asm,0,0,errtext);
memcpy(pcode,t_asm.code,len);pcode += len;
ExecuteCode((BYTE*)codedata,pcode-codedata);
ClearList();
}
else//否则清除链表
{
ClearList();
}
}
else if( da->cmdtype == C_RET )//遇到返回清除
{
ClearList();
}
else//否则添加到链表
{
InsetList(da);
}
}
int _tmain(int argc, _TCHAR* argv[])
{
CPEStructure PEStructure;
if( argc < 2 )
{
delete[] codedata;codedata = NULL;
printf("请输入分析参数如 - VParse.exe StrDiggerMe.exe\n");
system("pause");
return 0;
}
if( !PEStructure.OpenFileName(argv[1]) )
{
delete[] codedata;codedata = NULL;
printf("请返回");
system("pause");
return 0;
}
handle = CreateFile("out.txt",GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL,0);
if( handle == INVALID_HANDLE_VALUE )
{
DWORD dw = GetLastError();
MsgBox("打开文件失败!");
return 0;
}
//得到入口点所在索引
int OEPidx = PEStructure.FindSectionIndex(PEStructure.image_nt_headers.OptionalHeader.AddressOfEntryPoint);
BYTE* pcode = SearchData((BYTE*)PEStructure.image_section[OEPidx],PEStructure.image_section_header[OEPidx].SizeOfRawData,(BYTE*)DecodeFlag,16);
if(!pcode)
{
delete[] codedata;codedata = NULL;
printf("没找到解码标志");
system("pause");
return 0;
}
pcode-=7;
VirtualBaseAddr = PEStructure.image_nt_headers.OptionalHeader.ImageBase + PEStructure.image_section_header[OEPidx].VirtualAddress;
FuncAddr = VirtualBaseAddr + (DWORD)(pcode - (BYTE*)PEStructure.image_section[OEPidx]);
int Segment_Len = PEStructure.image_section_header[OEPidx].SizeOfRawData;//段长度
char* paddr = PEStructure.image_section[OEPidx];
int Segment_End = VirtualBaseAddr + Segment_Len;
DWORD StepVirtualAddr = VirtualBaseAddr;
while( StepVirtualAddr < Segment_End )
{
t_disasm da;
int len = Disasm(paddr,16,StepVirtualAddr,&da,DISASM_CODE);
IdentifyCode(&da);
StepVirtualAddr += len;
paddr += len;
}
delete[] codedata;codedata = NULL;
CloseHandle(handle);
return 0;
}
[招生]科锐逆向工程师培训(2024年11月15日实地，远程教学同时开班, 第51期)
