此程序建立了一个TCP服务端,端口号为10010,之后accept等待连接,如果接受到连接,那么就发送一些欢迎信息,以及提示信息---发送quit退出.
之后不停地调用recv,如果接受到数据,那么判断是否为quit,是则退出,否则进入401e00对接收到的数据进行加密
,之后把加密后的数据发送回客户端:
之后跳回recv等待.
加密过程401e00抠出,如下:
;第一步 抠出加密函数 .586 .model flat,stdcall option casemap:none include msvcrt.inc ; include windows.inc ; include kernel32.inc ; ; includelib msvcrt.lib includelib KERNEL32.LIB .data format db "%s",0 string db "1234567890",0 ecode db 041h, 00eh, 097h, 0a3h, 02bh, 05ah, 0b7h, 06dh, 039h, 030h, 036h src db 100 dup(1) buf db 100 dup(0) var_98C dd 000000000h var_988 dd 000000000h var_984 dd 000000002h var_980 dd 000802001h, 000002081h, 000002081h, 000000080h, 000802080h, 000800081h, 000800001h, 000002001h, 000000000h, 000802000h, 000802000h, 000802081h, 000000081h, 000000000h, 000800080h, 000800001h dd 000000001h, 000002000h, 000800000h, 000802001h, 000000080h, 000800000h, 000002001h, 000002080h, 000800081h, 000000001h, 000002080h, 000800080h, 000002000h, 000802080h, 000802081h, 000000081h dd 000800080h, 000800001h, 000802000h, 000802081h, 000000081h, 000000000h, 000000000h, 000802000h, 000002080h, 000800080h, 000800081h, 000000001h, 000802001h, 000002081h, 000002081h, 000000080h dd 000802081h, 000000081h, 000000001h, 000002000h, 000800001h, 000002001h, 000802080h, 000800081h, 000002001h, 000002080h, 000800000h, 000802001h, 000000080h, 000800000h, 000002000h, 000802080h var_880 dd 080108020h, 080008000h, 000008000h, 000108020h, 000100000h, 000000020h, 080100020h, 080008020h, 080000020h, 080108020h, 080108000h, 080000000h, 080008000h, 000100000h, 000000020h, 080100020h dd 000108000h, 000100020h, 080008020h, 000000000h, 080000000h, 000008000h, 000108020h, 080100000h, 000100020h, 080000020h, 000000000h, 000108000h, 000008020h, 080108000h, 080100000h, 000008020h dd 000000000h, 000108020h, 080100020h, 000100000h, 080008020h, 080100000h, 080108000h, 000008000h, 080100000h, 080008000h, 000000020h, 080108020h, 000108020h, 000000020h, 000008000h, 080000000h dd 000008020h, 080108000h, 000100000h, 080000020h, 000100020h, 080008020h, 080000020h, 000100020h, 000108000h, 000000000h, 080008000h, 000008020h, 080000000h, 080100020h, 080108020h, 000108000h var_780 dd 001010400h, 000000000h, 000010000h, 001010404h, 001010004h, 000010404h, 000000004h, 000010000h, 000000400h, 001010400h, 001010404h, 000000400h, 001000404h, 001010004h, 001000000h, 000000004h dd 000000404h, 001000400h, 001000400h, 000010400h, 000010400h, 001010000h, 001010000h, 001000404h, 000010004h, 001000004h, 001000004h, 000010004h, 000000000h, 000000404h, 000010404h, 001000000h dd 000010000h, 001010404h, 000000004h, 001010000h, 001010400h, 001000000h, 001000000h, 000000400h, 001010004h, 000010000h, 000010400h, 001000004h, 000000400h, 000000004h, 001000404h, 000010404h dd 001010404h, 000010004h, 001010000h, 001000404h, 001000004h, 000000404h, 000010404h, 001010400h, 000000404h, 001000400h, 001000400h, 000000000h, 000010004h, 000010400h, 000000000h, 001010004h var_680 dd 020000010h, 020400000h, 000004000h, 020404010h, 020400000h, 000000010h, 020404010h, 000400000h, 020004000h, 000404010h, 000400000h, 020000010h, 000400010h, 020004000h, 020000000h, 000004010h dd 000000000h, 000400010h, 020004010h, 000004000h, 000404000h, 020004010h, 000000010h, 020400010h, 020400010h, 000000000h, 000404010h, 020404000h, 000004010h, 000404000h, 020404000h, 020000000h dd 020004000h, 000000010h, 020400010h, 000404000h, 020404010h, 000400000h, 000004010h, 020000010h, 000400000h, 020004000h, 020000000h, 000004010h, 020000010h, 020404010h, 000404000h, 020400000h dd 000404010h, 020404000h, 000000000h, 020400010h, 000000010h, 000004000h, 020400000h, 000404010h, 000004000h, 000400010h, 020004010h, 000000000h, 020404000h, 020000000h, 000400010h, 020004010h var_580 dd 010001040h, 000001000h, 000040000h, 010041040h, 010000000h, 010001040h, 000000040h, 010000000h, 000040040h, 010040000h, 010041040h, 000041000h, 010041000h, 000041040h, 000001000h, 000000040h dd 010040000h, 010000040h, 010001000h, 000001040h, 000041000h, 000040040h, 010040040h, 010041000h, 000001040h, 000000000h, 000000000h, 010040040h, 010000040h, 010001000h, 000041040h, 000040000h dd 000041040h, 000040000h, 010041000h, 000001000h, 000000040h, 010040040h, 000001000h, 000041040h, 010001000h, 000000040h, 010000040h, 010040000h, 010040040h, 010000000h, 000040000h, 010001040h dd 000000000h, 010041040h, 000040040h, 010000040h, 010040000h, 010001000h, 010001040h, 000000000h, 010041040h, 000041000h, 000041000h, 000001040h, 000001040h, 000040040h, 010000000h, 010041000h var_480 dd 000000100h, 002080100h, 002080000h, 042000100h, 000080000h, 000000100h, 040000000h, 002080000h, 040080100h, 000080000h, 002000100h, 040080100h, 042000100h, 042080000h, 000080100h, 040000000h dd 002000000h, 040080000h, 040080000h, 000000000h, 040000100h, 042080100h, 042080100h, 002000100h, 042080000h, 040000100h, 000000000h, 042000000h, 002080100h, 002000000h, 042000000h, 000080100h dd 000080000h, 042000100h, 000000100h, 002000000h, 040000000h, 002080000h, 042000100h, 040080100h, 002000100h, 040000000h, 042080000h, 002080100h, 040080100h, 000000100h, 002000000h, 042080000h dd 042080100h, 000080100h, 042000000h, 042080100h, 002080000h, 000000000h, 040080000h, 042000000h, 000080100h, 002000100h, 040000100h, 000080000h, 000000000h, 040080000h, 002080100h, 040000100h var_380 dd 000200000h, 004200002h, 004000802h, 000000000h, 000000800h, 004000802h, 000200802h, 004200800h, 004200802h, 000200000h, 000000000h, 004000002h, 000000002h, 004000000h, 004200002h, 000000802h dd 004000800h, 000200802h, 000200002h, 004000800h, 004000002h, 004200000h, 004200800h, 000200002h, 004200000h, 000000800h, 000000802h, 004200802h, 000200800h, 000000002h, 004000000h, 000200800h dd 004000000h, 000200800h, 000200000h, 004000802h, 004000802h, 004200002h, 004200002h, 000000002h, 000200002h, 004000000h, 004000800h, 000200000h, 004200800h, 000000802h, 000200802h, 004200800h dd 000000802h, 004000002h, 004200802h, 004200000h, 000200800h, 000000000h, 000000002h, 004200802h, 000000000h, 000200802h, 004200000h, 000000800h, 004000002h, 004000800h, 000000800h, 000200002h var_280 dd 000000208h, 008020200h, 000000000h, 008020008h, 008000200h, 000000000h, 000020208h, 008000200h, 000020008h, 008000008h, 008000008h, 000020000h, 008020208h, 000020008h, 008020000h, 000000208h dd 008000000h, 000000008h, 008020200h, 000000200h, 000020200h, 008020000h, 008020008h, 000020208h, 008000208h, 000020200h, 000020000h, 008000208h, 000000008h, 008020208h, 000000200h, 008000000h dd 008020200h, 008000000h, 000020008h, 000000208h, 000020000h, 008020200h, 008000200h, 000000000h, 000000200h, 000020008h, 008020208h, 008000200h, 008000008h, 000000200h, 000000000h, 008020008h dd 008000208h, 000020000h, 008000000h, 008020208h, 000000008h, 000020208h, 000020200h, 008000008h, 008020000h, 008000208h, 000000208h, 008020000h, 000020208h, 000000008h, 008020008h, 000020200h Dst dd 002002608h var_17C dd 010200e3ah, 000242327h, 004000431h, 000042834h, 020002b26h, 000241613h, 00008003fh, 001203811h, 020001f00h, 00020340eh, 020093015h, 005000b0ch, 02008030eh, 001000525h, 0000d3c13h dd 020103f04h, 008001a21h, 000100e3ah, 003000816h, 020181107h, 001002b30h, 020002432h, 00300330bh, 020081c0dh, 00220052dh, 002082910h, 002002413h, 000081a25h, 00030321ch, 000001d29h, 00402090ah dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h .code GetXor proc retn GetXor endp Ecode proc ;arg_0:dword,len:dword push ebp mov ebp,esp pushad xor esi,esi mov ebx,[ebp+0ch] shr ebx, 2 ; ebx = 数据长度 add esp, 10h xor edi, edi mov [var_984], ebx cmp ebx, esi jbe loc_40332F lea esp, [esp+0] mov esi, [ebp+8] loc_403100: ; CODE XREF: sub_401E00+1529j mov edx, [ebp+8] mov eax, [edx+edi*4] mov edx, [edx+edi*4+4] mov ecx, eax mov ebx, eax shr ebx, 10h and ecx, 0FF0000h or ecx, ebx mov ebx, eax and eax, 0FF00h shl ebx, 10h or ebx, eax mov eax, edx shl ebx, 8 shr ecx, 8 or ecx, ebx mov ebx, edx and eax, 0FF0000h shr ebx, 10h or eax, ebx mov ebx, edx and edx, 0FF00h shl ebx, 10h or ebx, edx shr eax, 8 shl ebx, 8 or eax, ebx mov edx, ecx shr edx, 4 xor edx, eax and edx, 0F0F0F0Fh xor eax, edx shl edx, 4 xor ecx, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, ecx shr edx, 1 xor edx, eax and edx, 55555555h lea ebx, [edx+edx] xor ebx, ecx xor eax, edx rol ebx, 1 rol eax, 1 xor ebp, ebp mov [var_98C], ebp mov ecx, eax loc_4031C4: ; CODE XREF: sub_401E00+145Cj mov eax, [ebp*4+Dst] xor eax, ecx mov edx, ecx ror edx, 4 xor edx, [ebp*4+var_17C] mov [var_988], ebx mov ebx, ecx mov ecx, eax shr ecx, 8 and ecx, 3Fh mov ecx, [ecx*4+var_680] mov ebp, edx shr ebp, 8 and ebp, 3Fh or ecx, [ebp*4+var_480] mov ebp, eax shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_980] mov ebp, edx shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_280] mov ebp, eax shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_880] mov ebp, edx shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_780] mov ebp, [var_98C] and eax, 3Fh or ecx, [eax*4+var_580] and edx, 3Fh or ecx, [edx*4+var_380] add ebp, 2 xor ecx, [var_988] mov [var_98C], ebp cmp ebp, 20h jnz loc_4031C4 ror ecx, 1 ror ebx, 1 mov edx, ecx shr edx, 1 mov eax, ebx xor edx, eax and edx, 55555555h xor eax, edx add edx, edx xor ecx, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov ebx, ecx shr ebx, 4 xor ebx, eax and ebx, 0F0F0F0Fh mov edx, ebx shl edx, 4 xor edx, ecx mov ebp, edx mov ecx, edx shr ecx, 10h and ebp, 0FF0000h or ebp, ecx mov ecx, edx xor eax, ebx and edx, 0FF00h shl ecx, 10h or ecx, edx mov edx, eax and edx, 0FF0000h mov ebx, eax shr ebx, 10h or edx, ebx mov ebx, eax shl ebx, 10h and eax, 0FF00h shl ecx, 8 or ebx, eax shr ebp, 8 or ebp, ecx mov ecx, esi shr edx, 8 shl ebx, 8 or edx, ebx mov [ecx+edi*4], ebp mov [ecx+edi*4+4], edx add edi, 2 cmp edi, [var_984] jb loc_403100 loc_40332F: popad sub esp,10h pop ebp ret 8 Ecode endp main: ;for test push 0ah push offset string call Ecode ret end main
;第二步 化解加密函数 .586 .model flat,stdcall option casemap:none include msvcrt.inc ; include windows.inc ; include kernel32.inc ; ; includelib msvcrt.lib includelib KERNEL32.LIB .data format db "%s",0 string db "1234567890",0 ecode db 041h, 00eh, 097h, 0a3h, 02bh, 05ah, 0b7h, 06dh, 039h, 030h, 036h src db 100 dup(1) buf db 100 dup(0) var_98C dd 000000000h var_988 dd 000000000h var_984 dd 000000002h var_980 dd 000802001h, 000002081h, 000002081h, 000000080h, 000802080h, 000800081h, 000800001h, 000002001h, 000000000h, 000802000h, 000802000h, 000802081h, 000000081h, 000000000h, 000800080h, 000800001h dd 000000001h, 000002000h, 000800000h, 000802001h, 000000080h, 000800000h, 000002001h, 000002080h, 000800081h, 000000001h, 000002080h, 000800080h, 000002000h, 000802080h, 000802081h, 000000081h dd 000800080h, 000800001h, 000802000h, 000802081h, 000000081h, 000000000h, 000000000h, 000802000h, 000002080h, 000800080h, 000800081h, 000000001h, 000802001h, 000002081h, 000002081h, 000000080h dd 000802081h, 000000081h, 000000001h, 000002000h, 000800001h, 000002001h, 000802080h, 000800081h, 000002001h, 000002080h, 000800000h, 000802001h, 000000080h, 000800000h, 000002000h, 000802080h var_880 dd 080108020h, 080008000h, 000008000h, 000108020h, 000100000h, 000000020h, 080100020h, 080008020h, 080000020h, 080108020h, 080108000h, 080000000h, 080008000h, 000100000h, 000000020h, 080100020h dd 000108000h, 000100020h, 080008020h, 000000000h, 080000000h, 000008000h, 000108020h, 080100000h, 000100020h, 080000020h, 000000000h, 000108000h, 000008020h, 080108000h, 080100000h, 000008020h dd 000000000h, 000108020h, 080100020h, 000100000h, 080008020h, 080100000h, 080108000h, 000008000h, 080100000h, 080008000h, 000000020h, 080108020h, 000108020h, 000000020h, 000008000h, 080000000h dd 000008020h, 080108000h, 000100000h, 080000020h, 000100020h, 080008020h, 080000020h, 000100020h, 000108000h, 000000000h, 080008000h, 000008020h, 080000000h, 080100020h, 080108020h, 000108000h var_780 dd 001010400h, 000000000h, 000010000h, 001010404h, 001010004h, 000010404h, 000000004h, 000010000h, 000000400h, 001010400h, 001010404h, 000000400h, 001000404h, 001010004h, 001000000h, 000000004h dd 000000404h, 001000400h, 001000400h, 000010400h, 000010400h, 001010000h, 001010000h, 001000404h, 000010004h, 001000004h, 001000004h, 000010004h, 000000000h, 000000404h, 000010404h, 001000000h dd 000010000h, 001010404h, 000000004h, 001010000h, 001010400h, 001000000h, 001000000h, 000000400h, 001010004h, 000010000h, 000010400h, 001000004h, 000000400h, 000000004h, 001000404h, 000010404h dd 001010404h, 000010004h, 001010000h, 001000404h, 001000004h, 000000404h, 000010404h, 001010400h, 000000404h, 001000400h, 001000400h, 000000000h, 000010004h, 000010400h, 000000000h, 001010004h var_680 dd 020000010h, 020400000h, 000004000h, 020404010h, 020400000h, 000000010h, 020404010h, 000400000h, 020004000h, 000404010h, 000400000h, 020000010h, 000400010h, 020004000h, 020000000h, 000004010h dd 000000000h, 000400010h, 020004010h, 000004000h, 000404000h, 020004010h, 000000010h, 020400010h, 020400010h, 000000000h, 000404010h, 020404000h, 000004010h, 000404000h, 020404000h, 020000000h dd 020004000h, 000000010h, 020400010h, 000404000h, 020404010h, 000400000h, 000004010h, 020000010h, 000400000h, 020004000h, 020000000h, 000004010h, 020000010h, 020404010h, 000404000h, 020400000h dd 000404010h, 020404000h, 000000000h, 020400010h, 000000010h, 000004000h, 020400000h, 000404010h, 000004000h, 000400010h, 020004010h, 000000000h, 020404000h, 020000000h, 000400010h, 020004010h var_580 dd 010001040h, 000001000h, 000040000h, 010041040h, 010000000h, 010001040h, 000000040h, 010000000h, 000040040h, 010040000h, 010041040h, 000041000h, 010041000h, 000041040h, 000001000h, 000000040h dd 010040000h, 010000040h, 010001000h, 000001040h, 000041000h, 000040040h, 010040040h, 010041000h, 000001040h, 000000000h, 000000000h, 010040040h, 010000040h, 010001000h, 000041040h, 000040000h dd 000041040h, 000040000h, 010041000h, 000001000h, 000000040h, 010040040h, 000001000h, 000041040h, 010001000h, 000000040h, 010000040h, 010040000h, 010040040h, 010000000h, 000040000h, 010001040h dd 000000000h, 010041040h, 000040040h, 010000040h, 010040000h, 010001000h, 010001040h, 000000000h, 010041040h, 000041000h, 000041000h, 000001040h, 000001040h, 000040040h, 010000000h, 010041000h var_480 dd 000000100h, 002080100h, 002080000h, 042000100h, 000080000h, 000000100h, 040000000h, 002080000h, 040080100h, 000080000h, 002000100h, 040080100h, 042000100h, 042080000h, 000080100h, 040000000h dd 002000000h, 040080000h, 040080000h, 000000000h, 040000100h, 042080100h, 042080100h, 002000100h, 042080000h, 040000100h, 000000000h, 042000000h, 002080100h, 002000000h, 042000000h, 000080100h dd 000080000h, 042000100h, 000000100h, 002000000h, 040000000h, 002080000h, 042000100h, 040080100h, 002000100h, 040000000h, 042080000h, 002080100h, 040080100h, 000000100h, 002000000h, 042080000h dd 042080100h, 000080100h, 042000000h, 042080100h, 002080000h, 000000000h, 040080000h, 042000000h, 000080100h, 002000100h, 040000100h, 000080000h, 000000000h, 040080000h, 002080100h, 040000100h var_380 dd 000200000h, 004200002h, 004000802h, 000000000h, 000000800h, 004000802h, 000200802h, 004200800h, 004200802h, 000200000h, 000000000h, 004000002h, 000000002h, 004000000h, 004200002h, 000000802h dd 004000800h, 000200802h, 000200002h, 004000800h, 004000002h, 004200000h, 004200800h, 000200002h, 004200000h, 000000800h, 000000802h, 004200802h, 000200800h, 000000002h, 004000000h, 000200800h dd 004000000h, 000200800h, 000200000h, 004000802h, 004000802h, 004200002h, 004200002h, 000000002h, 000200002h, 004000000h, 004000800h, 000200000h, 004200800h, 000000802h, 000200802h, 004200800h dd 000000802h, 004000002h, 004200802h, 004200000h, 000200800h, 000000000h, 000000002h, 004200802h, 000000000h, 000200802h, 004200000h, 000000800h, 004000002h, 004000800h, 000000800h, 000200002h var_280 dd 000000208h, 008020200h, 000000000h, 008020008h, 008000200h, 000000000h, 000020208h, 008000200h, 000020008h, 008000008h, 008000008h, 000020000h, 008020208h, 000020008h, 008020000h, 000000208h dd 008000000h, 000000008h, 008020200h, 000000200h, 000020200h, 008020000h, 008020008h, 000020208h, 008000208h, 000020200h, 000020000h, 008000208h, 000000008h, 008020208h, 000000200h, 008000000h dd 008020200h, 008000000h, 000020008h, 000000208h, 000020000h, 008020200h, 008000200h, 000000000h, 000000200h, 000020008h, 008020208h, 008000200h, 008000008h, 000000200h, 000000000h, 008020008h dd 008000208h, 000020000h, 008000000h, 008020208h, 000000008h, 000020208h, 000020200h, 008000008h, 008020000h, 008000208h, 000000208h, 008020000h, 000020208h, 000000008h, 008020008h, 000020200h Dst dd 002002608h var_17C dd 010200e3ah, 000242327h, 004000431h, 000042834h, 020002b26h, 000241613h, 00008003fh, 001203811h, 020001f00h, 00020340eh, 020093015h, 005000b0ch, 02008030eh, 001000525h, 0000d3c13h dd 020103f04h, 008001a21h, 000100e3ah, 003000816h, 020181107h, 001002b30h, 020002432h, 00300330bh, 020081c0dh, 00220052dh, 002082910h, 002002413h, 000081a25h, 00030321ch, 000001d29h, 00402090ah dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h .code InitXor proc near push ebp mov ebp,esp mov edx, [ebp+8] mov eax, [edx+edi*4] mov edx, [edx+edi*4+4] mov ecx, eax mov ebx, eax shr ebx, 10h and ecx, 0FF0000h or ecx, ebx mov ebx, eax and eax, 0FF00h shl ebx, 10h or ebx, eax mov eax, edx shl ebx, 8 shr ecx, 8 or ecx, ebx mov ebx, edx and eax, 0FF0000h shr ebx, 10h or eax, ebx mov ebx, edx and edx, 0FF00h shl ebx, 10h or ebx, edx shr eax, 8 shl ebx, 8 or eax, ebx mov edx, ecx shr edx, 4 xor edx, eax and edx, 0F0F0F0Fh xor eax, edx shl edx, 4 xor ecx, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, ecx shr edx, 1 xor edx, eax and edx, 55555555h lea ebx, [edx+edx] xor ebx, ecx xor eax, edx rol ebx, 1 rol eax, 1 pop ebp retn 4 InitXor endp LoopXor proc near ; 操作 ebx,eax，返回 ebx,ecx xor ebp, ebp mov [var_98C], ebp mov ecx, eax loc_4031C4: ; CODE XREF: sub_401E00+145Cj mov eax, [ebp*4+Dst] xor eax, ecx mov edx, ecx ror edx, 4 xor edx, [ebp*4+var_17C] mov [var_988], ebx mov ebx, ecx mov ecx, eax shr ecx, 8 and ecx, 3Fh mov ecx, [ecx*4+var_680] mov ebp, edx shr ebp, 8 and ebp, 3Fh or ecx, [ebp*4+var_480] mov ebp, eax shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_980] mov ebp, edx shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_280] mov ebp, eax shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_880] mov ebp, edx shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_780] mov ebp, [var_98C] and eax, 3Fh or ecx, [eax*4+var_580] and edx, 3Fh or ecx, [edx*4+var_380] add ebp, 2 xor ecx, [var_988] mov [var_98C], ebp cmp ebp, 20h jnz loc_4031C4 retn LoopXor endp ExitXor proc near ror ecx, 1 ror ebx, 1 mov edx, ecx shr edx, 1 mov eax, ebx xor edx, eax and edx, 55555555h xor eax, edx add edx, edx xor ecx, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov ebx, ecx shr ebx, 4 xor ebx, eax and ebx, 0F0F0F0Fh mov edx, ebx shl edx, 4 xor edx, ecx mov ebp, edx mov ecx, edx shr ecx, 10h and ebp, 0FF0000h or ebp, ecx mov ecx, edx xor eax, ebx and edx, 0FF00h shl ecx, 10h or ecx, edx mov edx, eax and edx, 0FF0000h mov ebx, eax shr ebx, 10h or edx, ebx mov ebx, eax shl ebx, 10h and eax, 0FF00h shl ecx, 8 or ebx, eax shr ebp, 8 or ebp, ecx shr edx, 8 shl ebx, 8 or edx, ebx retn ExitXor endp Ecode proc ;arg_0:dword,len:dword push ebp mov ebp,esp pushad xor esi,esi mov ebx,[ebp+0ch] shr ebx, 2 ; ebx = 数据长度 add esp, 10h xor edi, edi mov [var_984], ebx cmp ebx, esi jbe loc_40332F lea esp, [esp+0] mov esi, [ebp+8] loc_403100: ; CODE XREF: sub_401E00+1529j push esi call InitXor ; 操作 eax,edx 返回 ebx,eax call LoopXor ; 操作 ebx,eax 返回 ebx,ecx call ExitXor ; 操作 ebx,ecx 返回 ebp,edx mov ecx, esi mov [ecx+edi*4], ebp mov [ecx+edi*4+4], edx add edi, 2 cmp edi, [var_984] jb loc_403100 loc_40332F: popad sub esp,10h pop ebp ret 8 Ecode endp
;第三步 根据加密函数写出解密函数 .586 .model flat,stdcall option casemap:none include msvcrt.inc ; include windows.inc ; include kernel32.inc ; ; includelib msvcrt.lib includelib KERNEL32.LIB .data format db "%s",0 string db "1234567890",0 ecode db 041h, 00eh, 097h, 0a3h, 02bh, 05ah, 0b7h, 06dh, 039h, 030h, 036h src db 100 dup(1) buf db 100 dup(0) var_98C dd 000000000h var_988 dd 000000000h var_984 dd 000000002h var_980 dd 000802001h, 000002081h, 000002081h, 000000080h, 000802080h, 000800081h, 000800001h, 000002001h, 000000000h, 000802000h, 000802000h, 000802081h, 000000081h, 000000000h, 000800080h, 000800001h dd 000000001h, 000002000h, 000800000h, 000802001h, 000000080h, 000800000h, 000002001h, 000002080h, 000800081h, 000000001h, 000002080h, 000800080h, 000002000h, 000802080h, 000802081h, 000000081h dd 000800080h, 000800001h, 000802000h, 000802081h, 000000081h, 000000000h, 000000000h, 000802000h, 000002080h, 000800080h, 000800081h, 000000001h, 000802001h, 000002081h, 000002081h, 000000080h dd 000802081h, 000000081h, 000000001h, 000002000h, 000800001h, 000002001h, 000802080h, 000800081h, 000002001h, 000002080h, 000800000h, 000802001h, 000000080h, 000800000h, 000002000h, 000802080h var_880 dd 080108020h, 080008000h, 000008000h, 000108020h, 000100000h, 000000020h, 080100020h, 080008020h, 080000020h, 080108020h, 080108000h, 080000000h, 080008000h, 000100000h, 000000020h, 080100020h dd 000108000h, 000100020h, 080008020h, 000000000h, 080000000h, 000008000h, 000108020h, 080100000h, 000100020h, 080000020h, 000000000h, 000108000h, 000008020h, 080108000h, 080100000h, 000008020h dd 000000000h, 000108020h, 080100020h, 000100000h, 080008020h, 080100000h, 080108000h, 000008000h, 080100000h, 080008000h, 000000020h, 080108020h, 000108020h, 000000020h, 000008000h, 080000000h dd 000008020h, 080108000h, 000100000h, 080000020h, 000100020h, 080008020h, 080000020h, 000100020h, 000108000h, 000000000h, 080008000h, 000008020h, 080000000h, 080100020h, 080108020h, 000108000h var_780 dd 001010400h, 000000000h, 000010000h, 001010404h, 001010004h, 000010404h, 000000004h, 000010000h, 000000400h, 001010400h, 001010404h, 000000400h, 001000404h, 001010004h, 001000000h, 000000004h dd 000000404h, 001000400h, 001000400h, 000010400h, 000010400h, 001010000h, 001010000h, 001000404h, 000010004h, 001000004h, 001000004h, 000010004h, 000000000h, 000000404h, 000010404h, 001000000h dd 000010000h, 001010404h, 000000004h, 001010000h, 001010400h, 001000000h, 001000000h, 000000400h, 001010004h, 000010000h, 000010400h, 001000004h, 000000400h, 000000004h, 001000404h, 000010404h dd 001010404h, 000010004h, 001010000h, 001000404h, 001000004h, 000000404h, 000010404h, 001010400h, 000000404h, 001000400h, 001000400h, 000000000h, 000010004h, 000010400h, 000000000h, 001010004h var_680 dd 020000010h, 020400000h, 000004000h, 020404010h, 020400000h, 000000010h, 020404010h, 000400000h, 020004000h, 000404010h, 000400000h, 020000010h, 000400010h, 020004000h, 020000000h, 000004010h dd 000000000h, 000400010h, 020004010h, 000004000h, 000404000h, 020004010h, 000000010h, 020400010h, 020400010h, 000000000h, 000404010h, 020404000h, 000004010h, 000404000h, 020404000h, 020000000h dd 020004000h, 000000010h, 020400010h, 000404000h, 020404010h, 000400000h, 000004010h, 020000010h, 000400000h, 020004000h, 020000000h, 000004010h, 020000010h, 020404010h, 000404000h, 020400000h dd 000404010h, 020404000h, 000000000h, 020400010h, 000000010h, 000004000h, 020400000h, 000404010h, 000004000h, 000400010h, 020004010h, 000000000h, 020404000h, 020000000h, 000400010h, 020004010h var_580 dd 010001040h, 000001000h, 000040000h, 010041040h, 010000000h, 010001040h, 000000040h, 010000000h, 000040040h, 010040000h, 010041040h, 000041000h, 010041000h, 000041040h, 000001000h, 000000040h dd 010040000h, 010000040h, 010001000h, 000001040h, 000041000h, 000040040h, 010040040h, 010041000h, 000001040h, 000000000h, 000000000h, 010040040h, 010000040h, 010001000h, 000041040h, 000040000h dd 000041040h, 000040000h, 010041000h, 000001000h, 000000040h, 010040040h, 000001000h, 000041040h, 010001000h, 000000040h, 010000040h, 010040000h, 010040040h, 010000000h, 000040000h, 010001040h dd 000000000h, 010041040h, 000040040h, 010000040h, 010040000h, 010001000h, 010001040h, 000000000h, 010041040h, 000041000h, 000041000h, 000001040h, 000001040h, 000040040h, 010000000h, 010041000h var_480 dd 000000100h, 002080100h, 002080000h, 042000100h, 000080000h, 000000100h, 040000000h, 002080000h, 040080100h, 000080000h, 002000100h, 040080100h, 042000100h, 042080000h, 000080100h, 040000000h dd 002000000h, 040080000h, 040080000h, 000000000h, 040000100h, 042080100h, 042080100h, 002000100h, 042080000h, 040000100h, 000000000h, 042000000h, 002080100h, 002000000h, 042000000h, 000080100h dd 000080000h, 042000100h, 000000100h, 002000000h, 040000000h, 002080000h, 042000100h, 040080100h, 002000100h, 040000000h, 042080000h, 002080100h, 040080100h, 000000100h, 002000000h, 042080000h dd 042080100h, 000080100h, 042000000h, 042080100h, 002080000h, 000000000h, 040080000h, 042000000h, 000080100h, 002000100h, 040000100h, 000080000h, 000000000h, 040080000h, 002080100h, 040000100h var_380 dd 000200000h, 004200002h, 004000802h, 000000000h, 000000800h, 004000802h, 000200802h, 004200800h, 004200802h, 000200000h, 000000000h, 004000002h, 000000002h, 004000000h, 004200002h, 000000802h dd 004000800h, 000200802h, 000200002h, 004000800h, 004000002h, 004200000h, 004200800h, 000200002h, 004200000h, 000000800h, 000000802h, 004200802h, 000200800h, 000000002h, 004000000h, 000200800h dd 004000000h, 000200800h, 000200000h, 004000802h, 004000802h, 004200002h, 004200002h, 000000002h, 000200002h, 004000000h, 004000800h, 000200000h, 004200800h, 000000802h, 000200802h, 004200800h dd 000000802h, 004000002h, 004200802h, 004200000h, 000200800h, 000000000h, 000000002h, 004200802h, 000000000h, 000200802h, 004200000h, 000000800h, 004000002h, 004000800h, 000000800h, 000200002h var_280 dd 000000208h, 008020200h, 000000000h, 008020008h, 008000200h, 000000000h, 000020208h, 008000200h, 000020008h, 008000008h, 008000008h, 000020000h, 008020208h, 000020008h, 008020000h, 000000208h dd 008000000h, 000000008h, 008020200h, 000000200h, 000020200h, 008020000h, 008020008h, 000020208h, 008000208h, 000020200h, 000020000h, 008000208h, 000000008h, 008020208h, 000000200h, 008000000h dd 008020200h, 008000000h, 000020008h, 000000208h, 000020000h, 008020200h, 008000200h, 000000000h, 000000200h, 000020008h, 008020208h, 008000200h, 008000008h, 000000200h, 000000000h, 008020008h dd 008000208h, 000020000h, 008000000h, 008020208h, 000000008h, 000020208h, 000020200h, 008000008h, 008020000h, 008000208h, 000000208h, 008020000h, 000020208h, 000000008h, 008020008h, 000020200h Dst dd 002002608h var_17C dd 010200e3ah, 000242327h, 004000431h, 000042834h, 020002b26h, 000241613h, 00008003fh, 001203811h, 020001f00h, 00020340eh, 020093015h, 005000b0ch, 02008030eh, 001000525h, 0000d3c13h dd 020103f04h, 008001a21h, 000100e3ah, 003000816h, 020181107h, 001002b30h, 020002432h, 00300330bh, 020081c0dh, 00220052dh, 002082910h, 002002413h, 000081a25h, 00030321ch, 000001d29h, 00402090ah dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h dd 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h, 000000000h debuf dd 000001d29h debuf2 dd 00402090ah dd 000081a25h, 00030321ch dd 002082910h, 002002413h dd 020081c0dh, 00220052dh dd 020002432h, 00300330bh dd 020181107h, 001002b30h dd 000100e3ah, 003000816h dd 020103f04h, 008001a21h dd 001000525h, 0000d3c13h dd 005000b0ch, 02008030eh dd 00020340eh, 020093015h dd 001203811h, 020001f00h dd 000241613h, 00008003fh dd 000042834h, 020002b26h dd 000242327h, 004000431h dd 002002608h, 010200e3ah .code InitXor proc near push ebp mov ebp,esp mov edx, [ebp+8] mov eax, [edx+edi*4] mov edx, [edx+edi*4+4] mov ecx, eax mov ebx, eax shr ebx, 10h and ecx, 0FF0000h or ecx, ebx mov ebx, eax and eax, 0FF00h shl ebx, 10h or ebx, eax mov eax, edx shl ebx, 8 shr ecx, 8 or ecx, ebx mov ebx, edx and eax, 0FF0000h shr ebx, 10h or eax, ebx mov ebx, edx and edx, 0FF00h shl ebx, 10h or ebx, edx shr eax, 8 shl ebx, 8 or eax, ebx mov edx, ecx shr edx, 4 xor edx, eax and edx, 0F0F0F0Fh xor eax, edx shl edx, 4 xor ecx, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, ecx shr edx, 1 xor edx, eax and edx, 55555555h lea ebx, [edx+edx] xor ebx, ecx xor eax, edx rol ebx, 1 rol eax, 1 pop ebp retn 4 InitXor endp LoopXor proc near ; 操作 ebx,eax，返回 ebx,ecx xor ebp, ebp mov [var_98C], ebp mov ecx, eax loc_4031C4: ; CODE XREF: sub_401E00+145Cj mov eax, [ebp*4+Dst] xor eax, ecx mov edx, ecx ror edx, 4 xor edx, [ebp*4+var_17C] mov [var_988], ebx mov ebx, ecx mov ecx, eax shr ecx, 8 and ecx, 3Fh mov ecx, [ecx*4+var_680] mov ebp, edx shr ebp, 8 and ebp, 3Fh or ecx, [ebp*4+var_480] mov ebp, eax shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_980] mov ebp, edx shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_280] mov ebp, eax shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_880] mov ebp, edx shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_780] mov ebp, [var_98C] and eax, 3Fh or ecx, [eax*4+var_580] and edx, 3Fh or ecx, [edx*4+var_380] add ebp, 2 xor ecx, [var_988] mov [var_98C], ebp cmp ebp, 20h jnz loc_4031C4 retn LoopXor endp ExitXor proc near ror ecx, 1 ror ebx, 1 mov edx, ecx shr edx, 1 mov eax, ebx xor edx, eax and edx, 55555555h xor eax, edx add edx, edx xor ecx, edx mov edx, eax shr edx, 8 xor edx, ecx and edx, 0FF00FFh xor ecx, edx shl edx, 8 xor eax, edx mov edx, eax shr edx, 2 xor edx, ecx and edx, 33333333h xor ecx, edx add edx, edx add edx, edx xor eax, edx mov edx, ecx shr edx, 10h xor edx, eax and edx, 0FFFFh xor eax, edx shl edx, 10h xor ecx, edx mov ebx, ecx shr ebx, 4 xor ebx, eax and ebx, 0F0F0F0Fh mov edx, ebx shl edx, 4 xor edx, ecx mov ebp, edx mov ecx, edx shr ecx, 10h and ebp, 0FF0000h or ebp, ecx mov ecx, edx xor eax, ebx and edx, 0FF00h shl ecx, 10h or ecx, edx mov edx, eax and edx, 0FF0000h mov ebx, eax shr ebx, 10h or edx, ebx mov ebx, eax shl ebx, 10h and eax, 0FF00h shl ecx, 8 or ebx, eax shr ebp, 8 or ebp, ecx shr edx, 8 shl ebx, 8 or edx, ebx retn ExitXor endp LoopXor2 proc near ; 操作 ebx,eax，返回 ebx,ecx xor ebp, ebp mov [var_98C], ebp mov ecx, eax LOOP1: ; CODE XREF: sub_401E00+145Cj mov eax, [ebp*4+debuf] xor eax, ecx mov edx, ecx ror edx, 4 xor edx, [ebp*4+debuf2] mov [var_988], ebx mov ebx, ecx mov ecx, eax shr ecx, 8 and ecx, 3Fh mov ecx, [ecx*4+var_680] mov ebp, edx shr ebp, 8 and ebp, 3Fh or ecx, [ebp*4+var_480] mov ebp, eax shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_980] mov ebp, edx shr ebp, 10h and ebp, 3Fh or ecx, [ebp*4+var_280] mov ebp, eax shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_880] mov ebp, edx shr ebp, 18h and ebp, 3Fh or ecx, [ebp*4+var_780] and eax, 3Fh or ecx, [eax*4+var_580] and edx, 3Fh or ecx, [edx*4+var_380] xor ecx, [var_988] mov ebp, [var_98C] add ebp, 2 mov [var_98C], ebp cmp ebp, 20h jne LOOP1 retn LoopXor2 endp Ecode proc ;arg_0:dword,len:dword push ebp mov ebp,esp pushad xor esi,esi mov ebx,[ebp+0ch] shr ebx, 2 ; ebx = 数据长度 add esp, 10h xor edi, edi mov [var_984], ebx cmp ebx, esi jbe loc_40332F lea esp, [esp+0] mov esi, [ebp+8] loc_403100: ; CODE XREF: sub_401E00+1529j push esi call InitXor ; 操作 eax,edx 返回 ebx,eax call LoopXor ; 操作 ebx,eax 返回 ebx,ecx call ExitXor ; 操作 ebx,ecx 返回 ebp,edx mov ecx, esi mov [ecx+edi*4], ebp mov [ecx+edi*4+4], edx add edi, 2 cmp edi, [var_984] jb loc_403100 loc_40332F: popad sub esp,10h pop ebp ret 8 Ecode endp decode proc push ebp mov ebp,esp pushad xor esi,esi mov ebx,[ebp+0ch] shr ebx, 2 ; ebx = 数据长度 add esp, 10h xor edi, edi mov [var_984], ebx cmp ebx, esi jbe loc_40332F lea esp, [esp+0] mov esi, [ebp+8] loc_403100: ; CODE XREF: sub_401E00+1529j push esi call InitXor ; 操作 eax,edx 返回 ebx,eax call LoopXor2 ; 操作 ebx,eax 返回 ebx,ecx call ExitXor ; 操作 ebx,ecx 返回 ebp,edx mov ecx, esi mov [ecx+edi*4], ebp mov [ecx+edi*4+4], edx add edi, 2 cmp edi, [var_984] jb loc_403100 loc_40332F: popad sub esp,10h pop ebp ret 8 decode endp DecodeBuf proc arg0:dword,arg1:dword push arg1 push arg0 call decode ret DecodeBuf endp end ;main: ;for test ; ; push 0ah ; push offset string ; call Ecode ; ; push 0ah ; push offset string ; call decode ; ; ; ret ; ; ;end main
将第三部代码放入RADASM编译后,导入VS项目,在test.cpp中声明一下,调用解密即可:
#define _WINSOCK_DEPRECATED_NO_WARNINGS #include <stdio.h> #include <WinSock2.h> #include <windows.h> #pragma comment (lib, "Ws2_32.lib") extern "C" void __stdcall DecodeBuf(DWORD, DWORD); int main() { WSADATA wd = { 0 }; WSAStartup(MAKEWORD(2, 2), &wd); SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); SOCKADDR_IN sai = { 0 }; sai.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); sai.sin_port = htons(10010); sai.sin_family = AF_INET; connect(s, (sockaddr*)&sai, sizeof(SOCKADDR_IN)); CHAR szToSend[100] = { 0 }; printf("请输入要发送的信息 "); scanf_s("%s", szToSend, 100); send(s, szToSend, 11, NULL); CHAR RecvBuf[200] = { 0 }; int nlen = recv(s, RecvBuf, 200, NULL); printf("接收到的加密了之后的信息: "); for (int i = 0; i < nlen; ++i) { printf("0x%x ", (BYTE)RecvBuf[i]); } printf(" "); DecodeBuf((DWORD)RecvBuf, nlen); printf("解密之后的信息:%s ",RecvBuf); system("pause"); send(s, "quit", 5, NULL); closesocket(s); WSACleanup(); return 0; }