【破文标题】Base64算法分析＋VC注册机代码
【破文作者】Vcsoft
【破解工具】OD
【破解平台】WINXP
【软件简介】生活小管家1.0版,就当是CrackMe了,只是感兴趣，没有其他目的。
失误之处敬请诸位大侠赐教!
下断 bp GetWindowTextA
填入试验码 9876543210654321 点注册 中断在USER32领空 CTRL＋F9返回程序领空
00436E05 |. 8B4D 10 mov ecx, [ebp+10]
00436E08 |. 6A FF push -1
00436E0A |. E8 A295FDFF call 004103B1
00436E0F |. /EB 0B jmp short 00436E1C
00436E11 |> |8B45 10 mov eax, [ebp+10]
00436E14 |. |FF30 push dword ptr [eax] ; /Arg2
00436E16 |. |56 push esi ; |Arg1
00436E17 |. |E8 16F6FFFF call 00436432 ; \CrackMe1.00436432
00436E1C |> \5F pop edi ; 0012ED0C
00436E1D |. 5E pop esi
00436E1E |. 5D pop ebp
00436E1F \. C2 0C00 retn 0C
------------------------------------------------------------------------------------
......省去非关键代码，跟着程序流程走，来到下面
0040EA63 . 8B46 74 mov eax, [esi+74]
0040EA66 . 8378 F4 10 cmp dword ptr [eax-C], 10 ; 比较试验码是不是16位
0040EA6A . 8D7E 74 lea edi, [esi+74]
0040EA6D . 74 24 je short 0040EA93 ; 是则跳往计算注册码
0040EA6F . 6A 00 push 0
0040EA71 . 68 C8F64300 push 0043F6C8
0040EA76 . 68 FC104400 push 004410FC
0040EA7B . 8BCE mov ecx, esi
0040EA7D . E8 85120200 call 0042FD07
0040EA82 . 5F pop edi
0040EA83 . 5E pop esi
0040EA84 . 8B4C24 0C mov ecx, [esp+C]
0040EA88 . 64:890D 00000>mov fs:[0], ecx
0040EA8F . 83C4 18 add esp, 18
0040EA92 . C3 retn
0040EA93 > 55 push ebp
0040EA94 . E8 75030200 call 0042EE0E
0040EA99 . 8B10 mov edx, [eax]
0040EA9B . 8BC8 mov ecx, eax
0040EA9D . FF52 0C call [edx+C]
0040EAA0 . 83C0 10 add eax, 10
0040EAA3 . 894424 10 mov [esp+10], eax
0040EAA7 . 8D4424 10 lea eax, [esp+10]
0040EAAB . 50 push eax ; /Arg2
0040EAAC . 8D6E 70 lea ebp, [esi+70] ; |
0040EAAF . 55 push ebp ; |Arg1
0040EAB0 . 8D4C24 1C lea ecx, [esp+1C] ; |
0040EAB4 . C74424 28 000>mov dword ptr [esp+28], 0 ; |
0040EABC . E8 0F77FFFF call 004061D0 ; \CrackMe1.004061D0
---------------------------------------------------------------------; 此处关键CALL，跟入
004061D0 /$ 6A FF push -1
004061D2 |. 68 B8C64300 push 0043C6B8 ; SE 处理程序安装
004061D7 |. 64:A1 0000000>mov eax, fs:[0]
004061DD |. 50 push eax
004061DE |. 64:8925 00000>mov fs:[0], esp
004061E5 |. 83EC 08 sub esp, 8
004061E8 |. 53 push ebx
004061E9 |. 8B5C24 1C mov ebx, [esp+1C]
004061ED |. 8B03 mov eax, [ebx]
004061EF |. 55 push ebp
004061F0 |. 8B68 F4 mov ebp, [eax-C] ; ebp = 机器码长度
004061F3 |. 85ED test ebp, ebp
004061F5 |. 894C24 0C mov [esp+C], ecx
004061F9 |. 7F 15 jg short 00406210
004061FB |. 5D pop ebp
004061FC |. 32C0 xor al, al
004061FE |. 5B pop ebx
004061FF |. 8B4C24 08 mov ecx, [esp+8]
00406203 |. 64:890D 00000>mov fs:[0], ecx
0040620A |. 83C4 14 add esp, 14
0040620D |. C2 0800 retn 8
00406210 |> 56 push esi
00406211 |. 57 push edi
00406212 |. 8D7D 01 lea edi, [ebp+1]
00406215 |. 57 push edi
00406216 |. E8 988B0200 call 0042EDB3
0040621B |. 8BF0 mov esi, eax
0040621D |. 8BCF mov ecx, edi
0040621F |. 8BD1 mov edx, ecx
00406221 |. C1E9 02 shr ecx, 2
00406224 |. 33C0 xor eax, eax
00406226 |. 8BFE mov edi, esi
00406228 |. F3:AB rep stos dword ptr es:[edi]
0040622A |. 8BCA mov ecx, edx
0040622C |. 83E1 03 and ecx, 3
0040622F |. F3:AA rep stos byte ptr es:[edi]
00406231 |. 8B03 mov eax, [ebx] ; eax = 机器码地址
00406233 |. 55 push ebp
00406234 |. 50 push eax
00406235 |. 56 push esi
00406236 |. E8 15800100 call 0041E250
0040623B |. 83C4 10 add esp, 10
0040623E |. 33C9 xor ecx, ecx ; cl = 0 循环计数器
00406240 |. 85ED test ebp, ebp
00406242 |. 7E 1C jle short 00406260
00406244 |> 8A0431 /mov al, [ecx+esi] ; al = 机器码各字符ASCII码-----------
00406247 |. 02C1 |add al, cl ; al = al + cl |
00406249 |. 8AD1 |mov dl, cl ; dl = cl |
0040624B |. FEC0 |inc al ; al++ |
0040624D |. C0E2 02 |shl dl, 2 ; dl左移2位 |
00406250 |. 32C2 |xor al, dl ; al^=dl |
00406252 |. 3C 30 |cmp al, 30 ; al 是否等于 0x30 运算1
00406254 |. 75 02 |jnz short 00406258 ; 不等则跳 |
00406256 |. B0 65 |mov al, 65 ; al = 0x30 则再加上0x65 |
00406258 |> 880431 |mov [ecx+esi], al ; 保存结果 |
0040625B |. 41 |inc ecx ; cl++ |
0040625C |. 3BCD |cmp ecx, ebp ; cl < 机器码长 |
0040625E |.^ 7C E4 \jl short 00406244 ; 循环------------------------------|
00406260 |> \56 push esi
00406261 |. 8D4C24 2C lea ecx, [esp+2C]
00406265 |. E8 96C8FFFF call 00402B00
0040626A |. 8D4424 28 lea eax, [esp+28]
0040626E |. 50 push eax
0040626F |. 8D4C24 14 lea ecx, [esp+14]
00406273 |. 51 push ecx
00406274 |. 8B4C24 1C mov ecx, [esp+1C]
00406278 |. C74424 28 000>mov dword ptr [esp+28], 0
00406280 |. E8 BBFBFFFF call 00405E40
00405E40 /$ 6A FF push -1
00405E42 |. 68 58C64300 push 0043C658 ; SE 处理程序安装
00405E47 |. 64:A1 0000000>mov eax, fs:[0]
00405E4D |. 50 push eax
00405E4E |. 64:8925 00000>mov fs:[0], esp
00405E55 |. 51 push ecx
00405E56 |. 53 push ebx
00405E57 |. C74424 04 000>mov dword ptr [esp+4], 0
00405E5F |. 55 push ebp
00405E60 |. 8B6C24 20 mov ebp, [esp+20]
00405E64 |. 8B45 00 mov eax, [ebp]
00405E67 |. 8B58 F4 mov ebx, [eax-C]
00405E6A |. 85DB test ebx, ebx
00405E6C |. 56 push esi
00405E6D |. 7F 26 jg short 00405E95
00405E6F |. 8B7424 20 mov esi, [esp+20]
00405E73 |. 68 F8FA4300 push 0043FAF8
00405E78 |. 8BCE mov ecx, esi
00405E7A |. E8 81CCFFFF call 00402B00
00405E7F |. 8BC6 mov eax, esi
00405E81 |. 5E pop esi
00405E82 |. 5D pop ebp
00405E83 |. 5B pop ebx
00405E84 |. 8B4C24 04 mov ecx, [esp+4]
00405E88 |. 64:890D 00000>mov fs:[0], ecx
00405E8F |. 83C4 10 add esp, 10
00405E92 |. C2 0800 retn 8
00405E95 |> 8D0C9D 000000>lea ecx, [ebx*4]
00405E9C |. B8 56555555 mov eax, 55555556
00405EA1 |. F7E9 imul ecx
00405EA3 |. 8BCA mov ecx, edx
00405EA5 |. C1E9 1F shr ecx, 1F
00405EA8 |. 03CA add ecx, edx
00405EAA |. 8BC3 mov eax, ebx
00405EAC |. 99 cdq
00405EAD |. BE 03000000 mov esi, 3
00405EB2 |. F7FE idiv esi
00405EB4 |. BE 4C000000 mov esi, 4C
00405EB9 |. 03CA add ecx, edx
00405EBB |. 8BC1 mov eax, ecx
00405EBD |. 99 cdq
00405EBE |. F7FE idiv esi
00405EC0 |. 85D2 test edx, edx
00405EC2 |. 74 18 je short 00405EDC
00405EC4 |. 81E2 03000080 and edx, 80000003
00405ECA |. 79 05 jns short 00405ED1
00405ECC |. 4A dec edx
00405ECD |. 83CA FC or edx, FFFFFFFC
00405ED0 |. 42 inc edx
00405ED1 |> 74 09 je short 00405EDC
00405ED3 |. BE 04000000 mov esi, 4
00405ED8 |. 2BF2 sub esi, edx
00405EDA |. 03CE add ecx, esi
00405EDC |> 57 push edi
00405EDD |. 8D7C41 02 lea edi, [ecx+eax*2+2]
00405EE1 |. 85FF test edi, edi
00405EE3 |. 897C24 10 mov [esp+10], edi
00405EE7 |. 0F8E BB000000 jle 00405FA8
00405EED |. 57 push edi
00405EEE |. E8 C08E0200 call 0042EDB3
00405EF3 |. 8BCF mov ecx, edi
00405EF5 |. 8BD1 mov edx, ecx
00405EF7 |. 8BF0 mov esi, eax
00405EF9 |. C1E9 02 shr ecx, 2
00405EFC |. 33C0 xor eax, eax
00405EFE |. 8BFE mov edi, esi
00405F00 |. F3:AB rep stos dword ptr es:[edi]
00405F02 |. 8BCA mov ecx, edx
00405F04 |. 83E1 03 and ecx, 3
00405F07 |. 83C4 04 add esp, 4
00405F0A |. F3:AA rep stos byte ptr es:[edi]
00405F0C |. E8 FD8E0200 call 0042EE0E
00405F11 |. 8B10 mov edx, [eax]
00405F13 |. 8BC8 mov ecx, eax
00405F15 |. FF52 0C call [edx+C]
00405F18 |. 83C0 10 add eax, 10
00405F1B |. 894424 28 mov [esp+28], eax
00405F1F |. 8B45 00 mov eax, [ebp]
00405F22 |. 6A 00 push 0
00405F24 |. 8D4C24 14 lea ecx, [esp+14]
00405F28 |. 51 push ecx
00405F29 |. 56 push esi
00405F2A |. 53 push ebx
00405F2B |. 50 push eax
00405F2C |. C74424 30 000>mov dword ptr [esp+30], 0
00405F34 |. E8 A7FBFFFF call 00405AE0 ; Base64 加密CALL？
------------------------------------------------------------------------跟进去看看就知道了
00405AE0 /$ 83EC 10 sub esp, 10
00405AE3 |. 53 push ebx
00405AE4 |. 56 push esi
00405AE5 |. 8B7424 1C mov esi, [esp+1C]
00405AE9 |. 85F6 test esi, esi
00405AEB |. 57 push edi
00405AEC |. 0F84 C5010000 je 00405CB7
00405AF2 |. 8B7C24 28 mov edi, [esp+28]
00405AF6 |. 85FF test edi, edi
00405AF8 |. 0F84 B9010000 je 00405CB7
00405AFE |. 8B5C24 2C mov ebx, [esp+2C]
00405B02 |. 85DB test ebx, ebx
00405B04 |. 0F84 AD010000 je 00405CB7
00405B0A |. 8B4424 30 mov eax, [esp+30]
00405B0E |. 55 push ebp
00405B0F |. 8B6C24 28 mov ebp, [esp+28]
00405B13 |. 50 push eax
00405B14 |. 55 push ebp
00405B15 |. E8 56FFFFFF call 00405A70
00405B1A |. 8B0B mov ecx, [ebx]
00405B1C |. 83C4 08 add esp, 8
00405B1F |. 3BC8 cmp ecx, eax
00405B21 |. 7D 0A jge short 00405B2D
00405B23 |. 5D pop ebp
00405B24 |. 5F pop edi
00405B25 |. 5E pop esi
00405B26 |. 33C0 xor eax, eax
00405B28 |. 5B pop ebx
00405B29 |. 83C4 10 add esp, 10
00405B2C |. C3 retn
00405B2D |> 8BC5 mov eax, ebp ; eax = ebp = 机器码长度
00405B2F |. 99 cdq
00405B30 |. B9 03000000 mov ecx, 3
00405B35 |. F7F9 idiv ecx ; 机器码长度/3
00405B37 |. B9 4C000000 mov ecx, 4C
00405B3C |. 33DB xor ebx, ebx
00405B3E |. BD 13000000 mov ebp, 13
00405B43 |. C1E0 02 shl eax, 2
00405B46 |. 895424 1C mov [esp+1C], edx ; 余下字节数存入[esp+1c]
00405B4A |. 99 cdq
00405B4B |. F7F9 idiv ecx
00405B4D |. 8BC8 mov ecx, eax
00405B4F |. 33C0 xor eax, eax
00405B51 |. 85C9 test ecx, ecx
00405B53 |. 895424 10 mov [esp+10], edx
00405B57 |. 894C24 14 mov [esp+14], ecx
00405B5B |. 894424 24 mov [esp+24], eax
00405B5F |. 0F8C C2000000 jl 00405C27
00405B65 |. 8B5424 34 mov edx, [esp+34]
00405B69 |. 83E2 02 and edx, 2
00405B6C |. 895424 18 mov [esp+18], edx
00405B70 |. 3BC1 cmp eax, ecx
00405B72 |> 75 0F /jnz short 00405B83
00405B74 |. 8B4424 10 |mov eax, [esp+10]
00405B78 |. 99 |cdq
00405B79 |. 83E2 03 |and edx, 3
00405B7C |. 03C2 |add eax, edx
00405B7E |. 8BE8 |mov ebp, eax
00405B80 |. C1FD 02 |sar ebp, 2 ; ebp循环次数=机器码长/3的商
00405B83 |> 85ED |test ebp, ebp
00405B85 |. 7E 6B |jle short 00405BF2
00405B87 |. 8BD5 |mov edx, ebp ; edx＝循环计数器
00405B89 |. 8DA424 000000>|lea esp, [esp]
00405B90 |> 0FB60E |/movzx ecx, byte ptr [esi] ; 取第1个字节
00405B93 |. 0FB646 01 ||movzx eax, byte ptr [esi+1] ; 取第2个字节
00405B97 |. C1E1 08 ||shl ecx, 8 ; ecx左移8位
00405B9A |. 0BC8 ||or ecx, eax ; 连接2个字节
00405B9C |. 46 ||inc esi ; pSrc++
00405B9D |. 0FB646 01 ||movzx eax, byte ptr [esi+1] ; 取第3个字节
00405BA1 |. C1E1 08 ||shl ecx, 8 ; ecx左移8位
00405BA4 |. 0BC8 ||or ecx, eax ; 连接3个字节
00405BA6 |. 46 ||inc esi ; pSrc++
00405BA7 |. C1E1 08 ||shl ecx, 8 ; ecx左移8位 3个字节编码为4个字符
00405BAA |. 8BC1 ||mov eax, ecx ; eax = ecx
00405BAC |. C1E8 1A ||shr eax, 1A ; eax 右移26位 得到第1组6bit
00405BAF |. 8A80 98FA4300 ||mov al, [eax+43FA98] ; 6bit的值作为索引查表
00405BB5 |. 8807 ||mov [edi], al ; 保存第1个加密后字符
00405BB7 |. C1E1 06 ||shl ecx, 6 ; 去掉前6bit
00405BBA |. 8BC1 ||mov eax, ecx ; eax = ecx
00405BBC |. C1E8 1A ||shr eax, 1A ; 得到第2组6bit
00405BBF |. 8A80 98FA4300 ||mov al, [eax+43FA98] ; 查表
00405BC5 |. 8847 01 ||mov [edi+1], al ; 保存第2个加密后字符
00405BC8 |. 46 ||inc esi ; pSrc++
00405BC9 |. C1E1 06 ||shl ecx, 6 ; 再去掉 6bit
00405BCC |. 47 ||inc edi ; pDst++
00405BCD |. 8BC1 ||mov eax, ecx ; eax = ecx
00405BCF |. C1E8 1A ||shr eax, 1A ; 得到第3组6bit
00405BD2 |. 8A80 98FA4300 ||mov al, [eax+43FA98] ; 查表
00405BD8 |. C1E9 14 ||shr ecx, 14 ; 直接右移20位得到第4组6bit
00405BDB |. 47 ||inc edi ; pDst++
00405BDC |. 8807 ||mov [edi], al ; 保存第3个加密后字符
00405BDE |. 83E1 3F ||and ecx, 3F ; 将前第4组6bit的前2bit置0
00405BE1 |. 8A89 98FA4300 ||mov cl, [ecx+43FA98] ; 查表
00405BE7 |. 47 ||inc edi ; pDst++
00405BE8 |. 880F ||mov [edi], cl ; 保存第4个加密后字符
00405BEA |. 47 ||inc edi ; pDst++
00405BEB |. 4A ||dec edx ; 循环计数器--
00405BEC |.^ 75 A2 |\jnz short 00405B90
00405BEE |. 8B4C24 14 |mov ecx, [esp+14]
00405BF2 |> 8B5424 18 |mov edx, [esp+18]
00405BF6 |. 85D2 |test edx, edx
00405BF8 |. 8D1CAB |lea ebx, [ebx+ebp*4]
00405BFB |. 75 0B |jnz short 00405C08
00405BFD |. C607 0D |mov byte ptr [edi], 0D ; 输出回车
00405C00 |. 47 |inc edi ; pDst++
00405C01 |. C607 0A |mov byte ptr [edi], 0A ; 输出换行
00405C04 |. 47 |inc edi ; pDst++
00405C05 |. 83C3 02 |add ebx, 2
00405C08 |> 8B4424 24 |mov eax, [esp+24]
00405C0C |. 40 |inc eax
00405C0D |. 3BC1 |cmp eax, ecx
00405C0F |. 894424 24 |mov [esp+24], eax
00405C13 |.^ 0F8E 59FFFFFF \jle 00405B72
00405C19 |. 85DB test ebx, ebx
00405C1B |. 74 0A je short 00405C27
00405C1D |. 85D2 test edx, edx
00405C1F |. 75 06 jnz short 00405C27
00405C21 |. 83EF 02 sub edi, 2
00405C24 |. 83EB 02 sub ebx, 2
00405C27 |> 8B4C24 1C mov ecx, [esp+1C] ; ecx = 余下字节数
00405C2B |. 85C9 test ecx, ecx
00405C2D |. 74 75 je short 00405CA4
00405C2F |. 8D69 01 lea ebp, [ecx+1]
00405C32 |. 85ED test ebp, ebp
00405C34 |. 74 6E je short 00405CA4
00405C36 |. 33C0 xor eax, eax
00405C38 |. 85C9 test ecx, ecx
00405C3A |. 7E 04 jle short 00405C40
00405C3C |. 0FB606 movzx eax, byte ptr [esi] ; 余下的字节
00405C3F |. 46 inc esi
00405C40 |> C1E0 08 shl eax, 8 ; eax左移8位
00405C43 |. 83F9 01 cmp ecx, 1 ; 是否余下1个字节
00405C46 |. 7E 06 jle short 00405C4E ; 不是
00405C48 |. 0FB616 movzx edx, byte ptr [esi] ; 再取1个字节
00405C4B |. 0BC2 or eax, edx ; 连接2个字节
00405C4D |. 46 inc esi
00405C4E |> C1E0 08 shl eax, 8 ; eax左移8位
00405C51 |. 83F9 02 cmp ecx, 2 ; 是否余下2个字节
00405C54 |. 7E 05 jle short 00405C5B ; 是
00405C56 |. 0FB60E movzx ecx, byte ptr [esi]
00405C59 |. 0BC1 or eax, ecx
00405C5B |> C1E0 08 shl eax, 8 ; eax左移8位
00405C5E |. 85ED test ebp, ebp
00405C60 |. 7E 16 jle short 00405C78
00405C62 |. 8BCD mov ecx, ebp
00405C64 |> 8BD0 /mov edx, eax
00405C66 |. C1EA 1A |shr edx, 1A ; edx右移26位 取6bit
00405C69 |. 8A92 98FA4300 |mov dl, [edx+43FA98] ; 查表
00405C6F |. 8817 |mov [edi], dl ; 保存
00405C71 |. 47 |inc edi
00405C72 |. C1E0 06 |shl eax, 6 ; eax左移6位
00405C75 |. 49 |dec ecx
00405C76 |.^ 75 EC \jnz short 00405C64
00405C78 |> 8A4424 34 mov al, [esp+34]
00405C7C |. 03DD add ebx, ebp ; 当前字符串长
00405C7E |. A8 01 test al, 1
00405C80 |. 75 22 jnz short 00405CA4
00405C82 |. BA 04000000 mov edx, 4
00405C87 |. 2BD5 sub edx, ebp
00405C89 |. 85D2 test edx, edx
00405C8B |. 7E 15 jle short 00405CA2
00405C8D |. 8BCA mov ecx, edx
00405C8F |. 8BF1 mov esi, ecx
00405C91 |. C1E9 02 shr ecx, 2
00405C94 |. B8 3D3D3D3D mov eax, 3D3D3D3D
00405C99 |. F3:AB rep stos dword ptr es:[edi]
00405C9B |. 8BCE mov ecx, esi
00405C9D |. 83E1 03 and ecx, 3
00405CA0 |. F3:AA rep stos byte ptr es:[edi] ; 不满4个字符用"="填充
00405CA2 |> 03DA add ebx, edx
00405CA4 |> 8B4424 30 mov eax, [esp+30]
00405CA8 |. 5D pop ebp
00405CA9 |. 5F pop edi
00405CAA |. 8918 mov [eax], ebx
00405CAC |. 5E pop esi ; 机密后的字符串
00405CAD |. B8 01000000 mov eax, 1
00405CB2 |. 5B pop ebx
00405CB3 |. 83C4 10 add esp, 10
00405CB6 |. C3 retn ; 返回
---------------------------------------------------------------------; 现在可以确定这是Base64加密函数了
00405F39 |. 83C4 14 add esp, 14
00405F3C |. 85C0 test eax, eax
00405F3E |. 74 13 je short 00405F53
00405F40 |. 56 push esi
00405F41 |. 8D5424 2C lea edx, [esp+2C]
00405F45 |. 68 D8FA4300 push 0043FAD8 ; ASCII "%s"
00405F4A |. 52 push edx
00405F4B |. E8 30C1FFFF call 00402080
00405F50 |. 83C4 0C add esp, 0C
00405F53 |> 56 push esi
00405F54 |. E8 558E0200 call 0042EDAE
00405F59 |. 8B7424 2C mov esi, [esp+2C]
00405F5D |. 83C6 F0 add esi, -10
00405F60 |. 56 push esi
00405F61 |. E8 3AB6FFFF call 004015A0
00405F66 |. 8B7C24 2C mov edi, [esp+2C]
00405F6A |. 83C0 10 add eax, 10
00405F6D |. 8907 mov [edi], eax
00405F6F |. 83C4 08 add esp, 8
00405F72 |. C74424 1C FFF>mov dword ptr [esp+1C], -1
00405F7A |. 8D46 0C lea eax, [esi+C]
00405F7D |. 83C9 FF or ecx, FFFFFFFF
00405F80 |. F0:0FC108 lock xadd [eax], ecx
00405F84 |. 49 dec ecx
00405F85 |. 85C9 test ecx, ecx
00405F87 |. 7F 08 jg short 00405F91
00405F89 |. 8B0E mov ecx, [esi]
00405F8B |. 8B11 mov edx, [ecx]
00405F8D |. 56 push esi
00405F8E |. FF52 04 call [edx+4]
00405F91 |> 8BC7 mov eax, edi
00405F93 |. 5F pop edi
00405F94 |. 5E pop esi
00405F95 |. 5D pop ebp
00405F96 |. 5B pop ebx
00405F97 |. 8B4C24 04 mov ecx, [esp+4]
00405F9B |. 64:890D 00000>mov fs:[0], ecx
00405FA2 |. 83C4 10 add esp, 10
00405FA5 |. C2 0800 retn 8 ; 返回
00406285 |. 8B4424 28 mov eax, [esp+28]
00406289 |. B3 02 mov bl, 2
0040628B |. 83C0 F0 add eax, -10
0040628E |. 885C24 20 mov [esp+20], bl
00406292 |. 8D50 0C lea edx, [eax+C]
00406295 |. 83C9 FF or ecx, FFFFFFFF
00406298 |. F0:0FC10A lock xadd [edx], ecx
0040629C |. 49 dec ecx
0040629D |. 85C9 test ecx, ecx
0040629F |. 7F 08 jg short 004062A9
004062A1 |. 8B08 mov ecx, [eax]
004062A3 |. 8B11 mov edx, [ecx]
004062A5 |. 50 push eax
004062A6 |. FF52 04 call [edx+4]
004062A9 |> 6A 10 push 10
004062AB |. 8D4424 18 lea eax, [esp+18]
004062AF |. 50 push eax
004062B0 |. 8D4C24 18 lea ecx, [esp+18]
004062B4 |. E8 17B8FFFF call 00401AD0 ; 这个CALL跟入
00401AD0 /$ 51 push ecx
00401AD1 |. 56 push esi
00401AD2 |. 57 push edi
00401AD3 |. 8B7C24 14 mov edi, [esp+14]
00401AD7 |. 85FF test edi, edi
00401AD9 |. C74424 08 000>mov dword ptr [esp+8], 0
00401AE1 |. 7D 02 jge short 00401AE5
00401AE3 |. 33FF xor edi, edi
00401AE5 |> 8B31 mov esi, [ecx]
00401AE7 |. 3B7E F4 cmp edi, [esi-C] ; 如果加密后字符数大于16位
00401AEA |. 7C 1D jl short 00401B09
00401AEC |. 8D46 F0 lea eax, [esi-10]
00401AEF |. 50 push eax
00401AF0 |. E8 ABFAFFFF call 004015A0
00401AF5 |. 83C4 04 add esp, 4
00401AF8 |. 8BC8 mov ecx, eax
00401AFA |. 8B4424 10 mov eax, [esp+10]
00401AFE |. 83C1 10 add ecx, 10
00401B01 |. 5F pop edi
00401B02 |. 8908 mov [eax], ecx
00401B04 |. 5E pop esi
00401B05 |. 59 pop ecx
00401B06 |. C2 0800 retn 8
00401B09 |> 8B4E F0 mov ecx, [esi-10]
00401B0C |. 8B11 mov edx, [ecx]
00401B0E |. FF52 10 call [edx+10]
00401B11 |. 50 push eax
00401B12 |. 57 push edi
00401B13 |. 56 push esi
00401B14 |. 8B7424 1C mov esi, [esp+1C]
00401B18 |. 8BCE mov ecx, esi
00401B1A |. E8 E1F8FFFF call 00401400 ; 截取前16位
00401B1F |. 5F pop edi
00401B20 |. 8BC6 mov eax, esi
00401B22 |. 5E pop esi
00401B23 |. 59 pop ecx
00401B24 \. C2 0800 retn 8 ; 返回
004062B9 |. 8B4C24 2C mov ecx, [esp+2C]
004062BD |. 50 push eax
004062BE |. C64424 24 03 mov byte ptr [esp+24], 3
004062C3 |. E8 28BBFFFF call 00401DF0
004062C8 |. 8B4424 14 mov eax, [esp+14]
004062CC |. 83C0 F0 add eax, -10
004062CF |. 885C24 20 mov [esp+20], bl
004062D3 |. 8D48 0C lea ecx, [eax+C]
004062D6 |. 83CA FF or edx, FFFFFFFF
004062D9 |. F0:0FC111 lock xadd [ecx], edx
004062DD |. 4A dec edx
004062DE |. 85D2 test edx, edx
004062E0 |. 7F 08 jg short 004062EA
004062E2 |. 8B08 mov ecx, [eax]
004062E4 |. 8B11 mov edx, [ecx]
004062E6 |. 50 push eax
004062E7 |. FF52 04 call [edx+4]
004062EA |> 56 push esi
004062EB |. E8 BE8A0200 call 0042EDAE
004062F0 |. 8B4424 14 mov eax, [esp+14]
004062F4 |. 83C0 F0 add eax, -10
004062F7 |. 83C4 04 add esp, 4
004062FA |. C74424 20 FFF>mov dword ptr [esp+20], -1
00406302 |. 8D48 0C lea ecx, [eax+C]
00406305 |. 83CA FF or edx, FFFFFFFF
00406308 |. F0:0FC111 lock xadd [ecx], edx
0040630C |. 4A dec edx
0040630D |. 85D2 test edx, edx
0040630F |. 5F pop edi
00406310 |. 5E pop esi
00406311 |. 7F 08 jg short 0040631B
00406313 |. 8B08 mov ecx, [eax]
00406315 |. 8B11 mov edx, [ecx]
00406317 |. 50 push eax
00406318 |. FF52 04 call [edx+4]
0040631B |> 8B4C24 10 mov ecx, [esp+10]
0040631F |. 5D pop ebp
00406320 |. B0 01 mov al, 1
00406322 |. 5B pop ebx
00406323 |. 64:890D 00000>mov fs:[0], ecx
0040632A |. 83C4 14 add esp, 14
0040632D \. C2 0800 retn 8 ; 返回
0040EAC1 . 8B07 mov eax, [edi]
0040EAC3 . 8B4C24 10 mov ecx, [esp+10]
0040EAC7 . 50 push eax
0040EAC8 . 51 push ecx
0040EAC9 . E8 9CE90000 call 0041D46A ; 比较真假注册码的每一位 相同EAX置0
0040EACE . 83C4 08 add esp, 8
0040EAD1 . 85C0 test eax, eax
0040EAD3 . 74 4B je short 0040EB20 ; eax = 0 跳向成功
0040EAD5 . 6A 00 push 0
0040EAD7 . 68 C8F64300 push 0043F6C8
0040EADC . 68 FC104400 push 004410FC
0040EAE1 . 8BCE mov ecx, esi
0040EAE3 . E8 1F120200 call 0042FD07 ; eax !=0 GAME OVER
小结：
机器码代入运算1中输出定义为T1
T1经过Base64运算输出定义为T2
取T2的前16位即为注册码
具体的实现请看下面的代码
const char EnBase64Tab[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
int EncodeBase64(const unsigned char* pSrc, char* pDst, int nSrcLen)
{
unsigned char c1, c2, c3;
int nDstLen = 0;
int nLineLen = 0;
int nDiv = nSrcLen / 3;
int nMod = nSrcLen % 3;
for (int i = 0; i < nDiv; i ++)
{
c1 = *pSrc++;
c2 = *pSrc++;
c3 = *pSrc++;
*pDst++ = EnBase64Tab[c1 >> 2];
*pDst++ = EnBase64Tab[((c1 << 4) | (c2 >> 4)) & 0x3f];
*pDst++ = EnBase64Tab[((c2 << 2) | (c3 >> 6)) & 0x3f];
*pDst++ = EnBase64Tab[c3 & 0x3f];
nLineLen += 4;
nDstLen += 4;
}
if (nMod == 1)
{
c1 = *pSrc++;
*pDst++ = EnBase64Tab[(c1 & 0xfc) >> 2];
*pDst++ = EnBase64Tab[((c1 & 0x03) << 4)];
*pDst++ = '=';
*pDst++ = '=';
nLineLen += 4;
nDstLen += 4;
}
else if (nMod == 2)
{
c1 = *pSrc++;
c2 = *pSrc++;
*pDst++ = EnBase64Tab[(c1 & 0xfc) >> 2];
*pDst++ = EnBase64Tab[((c1 & 0x03) << 4) | ((c2 & 0xf0) >> 4)];
*pDst++ = EnBase64Tab[((c2 & 0x0f) << 2)];
*pDst++ = '=';
nDstLen += 4;
}
*pDst = '\0';
return nDstLen;
}
void CKeyGenDlg::OnButton1()
{
// TODO: Add your control notification handler code here
CString in,out;
char al,dl,en64[50];
unsigned char temp[50];
GetDlgItemText(IDC_EDIT1,in);
int len=strlen(in);
char *mac=in.GetBuffer(strlen(in));
for(int i=0;i<len;i++)
{
al=(mac[i]+=i);
dl=i;
al+=1;
dl=dl<<2 & 0x000000ff;
al^=dl;
if(al==0x30) al+=0x65;
temp[i]=al;
}
temp[i]='\0';
EncodeBase64(temp,en64,i);
out=en64;
out=out.Left(16);
SetDlgItemText(IDC_EDIT2,out);
}