【软件名称】 e软代理服务器
【下载地址】 http://www.esoftsoft.com/
【声明】 只是感兴趣,没有其他目的。失误之处敬请诸位大侠赐教!
这是一个代理服务器软件,无壳,delphi程序。
程序采用机器码/授权文件方式注册,随便输入一些注册信息后点击验证按纽,提示错误信息。
delphi的当然先用dede来看看了,dede分析后找到对授权文件验证按纽点击事件的处理的地方:
1,
TFrmMain.SpeedButton13Click:
0059CC48 55 push ebp
0059CC49 8BEC mov ebp, esp
0059CC4B 6A00 push $00
0059CC4D 53 push ebx
0059CC4E 8BD8 mov ebx, eax
0059CC50 33C0 xor eax, eax
0059CC52 55 push ebp
* Possible String Reference to: '閝u?腽[Y]?
|
0059CC53 68E2CC5900 push $0059CCE2
***** TRY
|
0059CC58 64FF30 push dword ptr fs:[eax]
0059CC5B 648920 mov fs:[eax], esp
0059CC5E 8BC3 mov eax, ebx
|
0059CC60 E833FEFFFF call 0059CA98
0059CC65 84C0 test al, al
0059CC67 741B jz 0059CC84
0059CC69 6A30 push $30
* Possible String Reference to: '[X软软件]提醒'
|
0059CC6B 68F0CC5900 push $0059CCF0
* Possible String Reference to: '你的注册码是正确的,恭喜你'
|
0059CC70 6800CD5900 push $0059CD00
0059CC75 8BC3 mov eax, ebx
* Reference to: Controls.TWinControl.GetHandle(TWinControl):HWND;
| or: QComCtrls.TTrackBar.GetHandle(TTrackBar):QClxSliderH;
| or: QComCtrls.TCustomViewControl.GetHandle(TCustomViewControl):QListViewH;
| or: QComCtrls.TCustomViewControl.ViewportHandle(TCustomViewControl):QWidgetH;
| or: QComCtrls.TCustomHeaderControl.GetHandle(TCustomHeaderControl):QHeaderH;
| or: QComCtrls.TCustomSpinEdit.GetHandle(TCustomSpinEdit):QClxSpinBoxH;
|
0059CC77 E87C23EBFF call 0044EFF8
0059CC7C 50 push eax
* Reference to: user32.MessageBoxA()
|
0059CC7D E8AAAEE6FF call 00407B2C
0059CC82 EB48 jmp 0059CCCC
0059CC84 8D55FC lea edx, [ebp-$04]
* Reference to control MemoRegister : TMemo
|
0059CC87 8B835C050000 mov eax, [ebx+$055C]
* Reference to: Controls.TControl.GetText(TControl):TCaption;
|
0059CC8D E856BBEAFF call 004487E8
0059CC92 837DFC00 cmp dword ptr [ebp-$04], +$00
0059CC96 751B jnz 0059CCB3
0059CC98 6A30 push $30
* Possible String Reference to: '[X软软件]提醒'
|
0059CC9A 68F0CC5900 push $0059CCF0
* Possible String Reference to: '对不起,你还没有注册,你的使用将受?
| 揭欢ǖ南拗疲?
|
0059CC9F 681CCD5900 push $0059CD1C
0059CCA4 8BC3 mov eax, ebx
* Reference to: Controls.TWinControl.GetHandle(TWinControl):HWND;
| or: QComCtrls.TTrackBar.GetHandle(TTrackBar):QClxSliderH;
| or: QComCtrls.TCustomViewControl.GetHandle(TCustomViewControl):QListViewH;
| or: QComCtrls.TCustomViewControl.ViewportHandle(TCustomViewControl):QWidgetH;
| or: QComCtrls.TCustomHeaderControl.GetHandle(TCustomHeaderControl):QHeaderH;
| or: QComCtrls.TCustomSpinEdit.GetHandle(TCustomSpinEdit):QClxSpinBoxH;
|
0059CCA6 E84D23EBFF call 0044EFF8
0059CCAB 50 push eax
* Reference to: user32.MessageBoxA()
|
0059CCAC E87BAEE6FF call 00407B2C
0059CCB1 EB19 jmp 0059CCCC
0059CCB3 6A30 push $30
* Possible String Reference to: '[X软软件]提醒'
|
0059CCB5 68F0CC5900 push $0059CCF0
* Possible String Reference to: '对不起,您的注册码是不正确的。你的?
| 褂媒艿揭欢ǖ南拗疲?
|
0059CCBA 6850CD5900 push $0059CD50
0059CCBF 8BC3 mov eax, ebx
* Reference to: Controls.TWinControl.GetHandle(TWinControl):HWND;
| or: QComCtrls.TTrackBar.GetHandle(TTrackBar):QClxSliderH;
| or: QComCtrls.TCustomViewControl.GetHandle(TCustomViewControl):QListViewH;
| or: QComCtrls.TCustomViewControl.ViewportHandle(TCustomViewControl):QWidgetH;
| or: QComCtrls.TCustomHeaderControl.GetHandle(TCustomHeaderControl):QHeaderH;
| or: QComCtrls.TCustomSpinEdit.GetHandle(TCustomSpinEdit):QClxSpinBoxH;
|
0059CCC1 E83223EBFF call 0044EFF8
0059CCC6 50 push eax
* Reference to: user32.MessageBoxA()
|
0059CCC7 E860AEE6FF call 00407B2C
0059CCCC 33C0 xor eax, eax
0059CCCE 5A pop edx
0059CCCF 59 pop ecx
0059CCD0 59 pop ecx
0059CCD1 648910 mov fs:[eax], edx
很容易就能找出注册是否成功的判断点:
0059CC60 E833FEFFFF call 0059CA98
0059CC65 84C0 test al, al
0059CC67 741B jz 0059CC84
0059CC65 84C0 test al, al
al为0则失败,al不是零就验证通过了。要爆破,把
0059CC67 741B jz 0059CC84
这句nop掉就可以了。
呵呵,这样也太简单了点吧:)
2,
下面来看看这个软件的授权文件验证算法:
进入验证call 0059CA98看看(以下牵涉到软件作者name以及phone的私人信息一律略过)
0059CA98 55 push ebp
0059CA99 8BEC mov ebp, esp
0059CA9B 33C9 xor ecx, ecx
0059CA9D 51 push ecx
0059CA9E 51 push ecx
0059CA9F 51 push ecx
0059CAA0 51 push ecx
0059CAA1 51 push ecx
0059CAA2 51 push ecx
0059CAA3 53 push ebx
0059CAA4 8BD8 mov ebx, eax
0059CAA6 33C0 xor eax, eax
0059CAA8 55 push ebp
* Possible String Reference to: '轸v?胫嬅[嬪]?
|
0059CAA9 685FCB5900 push $0059CB5F
***** TRY
|
0059CAAE 64FF30 push dword ptr fs:[eax]
0059CAB1 648920 mov fs:[eax], esp
0059CAB4 8B0D04FB5300 mov ecx, [$0053FB04]
* Possible String Reference to: '作者的名字'
|
0059CABA BA78CB5900 mov edx, $0059CB78
* Reference to control DCP_blowfish1 : TDCP_blowfish
|
0059CABF 8B834C050000 mov eax, [ebx+$054C]
|
0059CAC5 E86EFEF9FF call 0053C938
0059CACA 8D55F4 lea edx, [ebp-$0C]
* Reference to control MemoRegister : TMemo
|
0059CACD 8B835C050000 mov eax, [ebx+$055C]
* Reference to: Controls.TControl.GetText(TControl):TCaption;
|
0059CAD3 E810BDEAFF call 004487E8 取得输入的注册信息
0059CAD8 8B45F4 mov eax, [ebp-$0C]
0059CADB 8D55F8 lea edx, [ebp-$08]
* Reference to: SysUtils.Trim(AnsiString):AnsiString;overload;
|
0059CADE E819C7E6FF call 004091FC
0059CAE3 8B55F8 mov edx, [ebp-$08]
0059CAE6 8D4DFC lea ecx, [ebp-$04]
* Reference to control DCP_blowfish1 : TDCP_blowfish
|
0059CAE9 8B834C050000 mov eax, [ebx+$054C]
0059CAEF 8B18 mov ebx, [eax]
0059CAF1 FF5358 call dword ptr [ebx+$58]
* Possible String Reference to: '作者的名字,软件信息,网站等等'
|
0059CAF4 6894CB5900 push $0059CB94
0059CAF9 8D45EC lea eax, [ebp-$14]
|
0059CAFC E8B75AFAFF call 005425B8 取网卡mac地址
0059CB01 FF75EC push dword ptr [ebp-$14]
0059CB04 8D45E8 lea eax, [ebp-$18]
* Reference to : TDCP_blowfish._PROC_00542348()
|
0059CB07 E83C58FAFF call 00542348 取硬盘物理序列号
0059CB0C FF75E8 push dword ptr [ebp-$18]
0059CB0F 8D45F0 lea eax, [ebp-$10]
0059CB12 BA03000000 mov edx, $00000003
|
0059CB17 E82C81E6FF call 00404C48
0059CB1C 8B55F0 mov edx, [ebp-$10]
0059CB1F 8B45FC mov eax, [ebp-$04]
* Reference to: System.@LStrCmp; 比较
|
0059CB22 E8A581E6FF call 00404CCC
0059CB27 7504 jnz 0059CB2D
0059CB29 B301 mov bl, $01
0059CB2B EB02 jmp 0059CB2F
0059CB2D 33DB xor ebx, ebx
0059CB2F 33C0 xor eax, eax
0059CB31 5A pop edx
0059CB32 59 pop ecx
0059CB33 59 pop ecx
0059CB34 648910 mov fs:[eax], edx
****** FINALLY
dede就是好,代码的流程大概清楚了,粗略的跟踪一下知道验证过程是:
读取输入的注册信息(做某些变换?)然后通过blowfish(encrypt还是decrypt?)算法处理后
与特定的字符串:
"'作者的名字,软件信息,网站等等'+'网卡mac'+'硬盘序列号'"进行比较,如果一样则验
证通过,注册成功。
这里用到了blowfish算法,要做的就是找出算法的key还有是encrypt还是decrypt。
粗略跟踪知道输入信息是在:
0059CAF1 |. FF53 58 CALL DWORD PTR DS:[EBX+58] ;
进行处理的,步过此call后就得到了后面和特定字符串比较的数据,进入call:
0053CCE0 . 53 PUSH EBX
0053CCE1 . 56 PUSH ESI
0053CCE2 . 57 PUSH EDI
0053CCE3 . 8BD9 MOV EBX,ECX
0053CCE5 . 8BFA MOV EDI,EDX
0053CCE7 . 8BF0 MOV ESI,EAX
0053CCE9 . 8BD3 MOV EDX,EBX
0053CCEB . 8BC7 MOV EAX,EDI
0053CCED . E8 16F5FFFF CALL EsoftPro.0053C208 对输入数据进行base64解码
0053CCF2 . 8B03 MOV EAX,DWORD PTR DS:[EBX]
0053CCF4 . E8 8F7EECFF CALL EsoftPro.00404B88
0053CCF9 . 50 PUSH EAX
0053CCFA . 8BC3 MOV EAX,EBX
0053CCFC . E8 D780ECFF CALL EsoftPro.00404DD8
0053CD01 . 50 PUSH EAX
0053CD02 . 8BC3 MOV EAX,EBX
0053CD04 . E8 CF80ECFF CALL EsoftPro.00404DD8
0053CD09 . 8BD0 MOV EDX,EAX
0053CD0B . 8BC6 MOV EAX,ESI
0053CD0D . 59 POP ECX
0053CD0E . 8B18 MOV EBX,DWORD PTR DS:[EAX]
0053CD10 . FF93 80000000 CALL DWORD PTR DS:[EBX+80] 对解码后的数据进一步的变换
0053CD16 . 5F POP EDI
0053CD17 . 5E POP ESI
0053CD18 . 5B POP EBX
0053CD19 . C3 RETN
base64解码:
0053C0D4 /$ 56 PUSH ESI
0053C0D5 |. 57 PUSH EDI
0053C0D6 |. 55 PUSH EBP
0053C0D7 |. 83C4 F0 ADD ESP,-10
0053C0DA |. 890C24 MOV DWORD PTR SS:[ESP],ECX
0053C0DD |. 8BF8 MOV EDI,EAX
0053C0DF |. 895424 08 MOV DWORD PTR SS:[ESP+8],EDX
0053C0E3 |. 33F6 XOR ESI,ESI
0053C0E5 |. 33ED XOR EBP,EBP
0053C0E7 |. 33C0 XOR EAX,EAX
0053C0E9 |. 8B1424 MOV EDX,DWORD PTR SS:[ESP]
0053C0EC |. 85D2 TEST EDX,EDX
0053C0EE |. 79 03 JNS SHORT EsoftPro.0053C0F3
0053C0F0 |. 83C2 03 ADD EDX,3
0053C0F3 |> C1FA 02 SAR EDX,2
0053C0F6 |. 85D2 TEST EDX,EDX
0053C0F8 |. 0F8E 02010000 JLE EsoftPro.0053C200
0053C0FE |. 895424 0C MOV DWORD PTR SS:[ESP+C],EDX
0053C102 |> BA 04000000 /MOV EDX,4 ;
0053C107 |. 8D4424 04 |LEA EAX,DWORD PTR SS:[ESP+4]
0053C10B |> 33C9 |/XOR ECX,ECX ;
0053C10D |. 8A0C37 ||MOV CL,BYTE PTR DS:[EDI+ESI]
0053C110 |. 83F9 3D ||CMP ECX,3D ; Switch (cases 2B..7A)
0053C113 |. 7F 14 ||JG SHORT EsoftPro.0053C129
0053C115 |. 74 52 ||JE SHORT EsoftPro.0053C169
0053C117 |. 83E9 2B ||SUB ECX,2B
0053C11A |. 74 43 ||JE SHORT EsoftPro.0053C15F
0053C11C |. 83E9 04 ||SUB ECX,4
0053C11F |. 74 43 ||JE SHORT EsoftPro.0053C164
0053C121 |. 49 ||DEC ECX
0053C122 |. 83E9 0A ||SUB ECX,0A
0053C125 |. 72 2B ||JB SHORT EsoftPro.0053C152
0053C127 |. EB 43 ||JMP SHORT EsoftPro.0053C16C
0053C129 |> 83C1 BF ||ADD ECX,-41
0053C12C |. 83E9 1A ||SUB ECX,1A
0053C12F |. 72 0A ||JB SHORT EsoftPro.0053C13B
0053C131 |. 83C1 FA ||ADD ECX,-6
0053C134 |. 83E9 1A ||SUB ECX,1A
0053C137 |. 72 0C ||JB SHORT EsoftPro.0053C145
0053C139 |. EB 31 ||JMP SHORT EsoftPro.0053C16C
0053C13B |> 8A0C37 ||MOV CL,BYTE PTR DS:[EDI+ESI] ; Cases 41 ('A'),42 ('B'),43 ('C'),44 ('D'),45 ('E'),46 ('F'),47 ('G'),48 ('H'),49 ('I'),4A ('J'),4B ('K'),4C ('L'),4D ('M'),4E ('N'),4F ('O'),50 ('P'),51 ('Q'),52 ('R'),53 ('S'),54 ('T')... of switch 0053C110
0053C13E |. 80E9 41 ||SUB CL,41
0053C141 |. 8808 ||MOV BYTE PTR DS:[EAX],CL
0053C143 |. EB 27 ||JMP SHORT EsoftPro.0053C16C
0053C145 |> 8A0C37 ||MOV CL,BYTE PTR DS:[EDI+ESI] ; Cases 61 ('a'),62 ('b'),63 ('c'),64 ('d'),65 ('e'),66 ('f'),67 ('g'),68 ('h'),69 ('i'),6A ('j'),6B ('k'),6C ('l'),6D ('m'),6E ('n'),6F ('o'),70 ('p'),71 ('q'),72 ('r'),73 ('s'),74 ('t')... of switch 0053C110
0053C148 |. 80E9 61 ||SUB CL,61
0053C14B |. 80C1 1A ||ADD CL,1A
0053C14E |. 8808 ||MOV BYTE PTR DS:[EAX],CL
0053C150 |. EB 1A ||JMP SHORT EsoftPro.0053C16C
0053C152 |> 8A0C37 ||MOV CL,BYTE PTR DS:[EDI+ESI] ; Cases 30 ('0'),31 ('1'),32 ('2'),33 ('3'),34 ('4'),35 ('5'),36 ('6'),37 ('7'),38 ('8'),39 ('9') of switch 0053C110
0053C155 |. 80E9 30 ||SUB CL,30
0053C158 |. 80C1 34 ||ADD CL,34
0053C15B |. 8808 ||MOV BYTE PTR DS:[EAX],CL
0053C15D |. EB 0D ||JMP SHORT EsoftPro.0053C16C
0053C15F |> C600 3E ||MOV BYTE PTR DS:[EAX],3E ; Case 2B ('+') of switch 0053C110
0053C162 |. EB 08 ||JMP SHORT EsoftPro.0053C16C
0053C164 |> C600 3F ||MOV BYTE PTR DS:[EAX],3F ; Case 2F ('/') of switch 0053C110
0053C167 |. EB 03 ||JMP SHORT EsoftPro.0053C16C
0053C169 |> C600 FF ||MOV BYTE PTR DS:[EAX],0FF ; Case 3D ('=') of switch 0053C110
0053C16C |> 46 ||INC ESI ; Default case of switch 0053C110
0053C16D |. 40 ||INC EAX
0053C16E |. 4A ||DEC EDX
0053C16F |.^75 9A |\JNZ SHORT EsoftPro.0053C10B
0053C171 |. 8A4424 04 |MOV AL,BYTE PTR SS:[ESP+4]
0053C175 |. C1E0 02 |SHL EAX,2
0053C178 |. 33D2 |XOR EDX,EDX
0053C17A |. 8A5424 05 |MOV DL,BYTE PTR SS:[ESP+5]
0053C17E |. C1EA 04 |SHR EDX,4
0053C181 |. 0AC2 |OR AL,DL
0053C183 |. 8B5424 08 |MOV EDX,DWORD PTR SS:[ESP+8]
0053C187 |. 88042A |MOV BYTE PTR DS:[EDX+EBP],AL
0053C18A |. 8D45 01 |LEA EAX,DWORD PTR SS:[EBP+1]
0053C18D |. 8A5424 06 |MOV DL,BYTE PTR SS:[ESP+6]
0053C191 |. 80FA FF |CMP DL,0FF
0053C194 |. 74 27 |JE SHORT EsoftPro.0053C1BD
0053C196 |. 807C24 07 FF |CMP BYTE PTR SS:[ESP+7],0FF
0053C19B |. 75 20 |JNZ SHORT EsoftPro.0053C1BD
0053C19D |. 8A4424 05 |MOV AL,BYTE PTR SS:[ESP+5]
0053C1A1 |. C1E0 04 |SHL EAX,4
0053C1A4 |. 81E2 FF000000 |AND EDX,0FF
0053C1AA |. C1EA 02 |SHR EDX,2
0053C1AD |. 0AC2 |OR AL,DL
0053C1AF |. 8B5424 08 |MOV EDX,DWORD PTR SS:[ESP+8]
0053C1B3 |. 88442A 01 |MOV BYTE PTR DS:[EDX+EBP+1],AL
0053C1B7 |. 8D45 02 |LEA EAX,DWORD PTR SS:[EBP+2]
0053C1BA |. 45 |INC EBP
0053C1BB |. EB 38 |JMP SHORT EsoftPro.0053C1F5
0053C1BD |> 80FA FF |CMP DL,0FF
0053C1C0 |. 74 33 |JE SHORT EsoftPro.0053C1F5
0053C1C2 |. 8A4424 05 |MOV AL,BYTE PTR SS:[ESP+5]
0053C1C6 |. C1E0 04 |SHL EAX,4
0053C1C9 |. 81E2 FF000000 |AND EDX,0FF
0053C1CF |. C1EA 02 |SHR EDX,2
0053C1D2 |. 0AC2 |OR AL,DL
0053C1D4 |. 8B5424 08 |MOV EDX,DWORD PTR SS:[ESP+8]
0053C1D8 |. 88442A 01 |MOV BYTE PTR DS:[EDX+EBP+1],AL
0053C1DC |. 8B4424 08 |MOV EAX,DWORD PTR SS:[ESP+8]
0053C1E0 |. 8A5424 06 |MOV DL,BYTE PTR SS:[ESP+6]
0053C1E4 |. C1E2 06 |SHL EDX,6
0053C1E7 |. 0A5424 07 |OR DL,BYTE PTR SS:[ESP+7]
0053C1EB |. 885428 02 |MOV BYTE PTR DS:[EAX+EBP+2],DL
0053C1EF |. 8D45 03 |LEA EAX,DWORD PTR SS:[EBP+3]
0053C1F2 |. 83C5 02 |ADD EBP,2
0053C1F5 |> 45 |INC EBP
0053C1F6 |. FF4C24 0C |DEC DWORD PTR SS:[ESP+C]
0053C1FA |.^0F85 02FFFFFF \JNZ EsoftPro.0053C102
0053C200 |> 83C4 10 ADD ESP,10
0053C203 |. 5D POP EBP
0053C204 |. 5F POP EDI
0053C205 |. 5E POP ESI
0053C206 \. C3 RETN
3,
进一步的变换:
(0053CD10 . FF93 80000000 CALL DWORD PTR DS:[EBX+80])
00540CBC /. 55 PUSH EBP
00540CBD |. 8BEC MOV EBP,ESP
00540CBF |. 83C4 E8 ADD ESP,-18
00540CC2 |. 53 PUSH EBX
00540CC3 |. 56 PUSH ESI
00540CC4 |. 57 PUSH EDI
00540CC5 |. 894D FC MOV DWORD PTR SS:[EBP-4],ECX
00540CC8 |. 8BD8 MOV EBX,EAX
00540CCA |. 807B 30 00 CMP BYTE PTR DS:[EBX+30],0
00540CCE |. 75 16 JNZ SHORT EsoftPro.00540CE6
00540CD0 |. B9 440D5400 MOV ECX,EsoftPro.00540D44 ; ASCII "Cipher not initialized"
00540CD5 |. B2 01 MOV DL,1
00540CD7 |. A1 08C65300 MOV EAX,DWORD PTR DS:[53C608]
00540CDC |. E8 A7C4ECFF CALL EsoftPro.0040D188
00540CE1 |. E8 AA35ECFF CALL EsoftPro.00404290
00540CE6 |> 8BF2 MOV ESI,EDX
00540CE8 |. 8B45 FC MOV EAX,DWORD PTR SS:[EBP-4]
00540CEB |. 8945 F8 MOV DWORD PTR SS:[EBP-8],EAX
00540CEE |. 8B45 08 MOV EAX,DWORD PTR SS:[EBP+8]
00540CF1 |. 85C0 TEST EAX,EAX
00540CF3 |. 76 3E JBE SHORT EsoftPro.00540D33
00540CF5 |. 8945 E8 MOV DWORD PTR SS:[EBP-18],EAX
00540CF8 |> 8A06 /MOV AL,BYTE PTR DS:[ESI]
00540CFA |. 8845 F7 |MOV BYTE PTR SS:[EBP-9],AL
00540CFD |. 8D4D EF |LEA ECX,DWORD PTR SS:[EBP-11]
00540D00 |. 8D53 40 |LEA EDX,DWORD PTR DS:[EBX+40]
00540D03 |. 8BC3 |MOV EAX,EBX
00540D05 |. 8B38 |MOV EDI,DWORD PTR DS:[EAX]
00540D07 |. FF57 6C |CALL DWORD PTR DS:[EDI+6C] blowfish_en
00540D0A |. 8A06 |MOV AL,BYTE PTR DS:[ESI]
00540D0C |. 3245 EF |XOR AL,BYTE PTR SS:[EBP-11]
00540D0F |. 8B55 F8 |MOV EDX,DWORD PTR SS:[EBP-8]
00540D12 |. 8802 |MOV BYTE PTR DS:[EDX],AL
00540D14 |. 8D53 40 |LEA EDX,DWORD PTR DS:[EBX+40]
00540D17 |. 8D43 41 |LEA EAX,DWORD PTR DS:[EBX+41]
00540D1A |. B9 07000000 |MOV ECX,7
00540D1F |. E8 681CECFF |CALL EsoftPro.0040298C
00540D24 |. 8A45 F7 |MOV AL,BYTE PTR SS:[EBP-9]
00540D27 |. 8843 47 |MOV BYTE PTR DS:[EBX+47],AL
00540D2A |. 46 |INC ESI
00540D2B |. FF45 F8 |INC DWORD PTR SS:[EBP-8]
00540D2E |. FF4D E8 |DEC DWORD PTR SS:[EBP-18]
00540D31 |.^75 C5 \JNZ SHORT EsoftPro.00540CF8
00540D33 |> 5F POP EDI
00540D34 |. 5E POP ESI
00540D35 |. 5B POP EBX
00540D36 |. 8BE5 MOV ESP,EBP
00540D38 |. 5D POP EBP
00540D39 \. C2 0400 RETN 4
分析这段代码知道变换过程是这样的:
设basedecode后得到的字符串为
"1234"
先对hex串'FA6A1510698C8467'运用blowfish加密得到hex串:
'4D72933486AEF1F0'
则ascii('1')^0x4d=0x7c,0x7c就是变换后的结果。
然后把ascii('1')添加到'FA6A1510698C8467'后面,得到‘FA6A1510698C846731'
再对'6A1510698C846731'运用blowfish加密。
加密结果的的头两位再与ascii('2')异或,得到变换结果的第2位,
如此循环处理len(base6解码后的字符串)次,依次连接变换后的结果,得到最后用来与特定字串
"'作者的名字,软件信息,网站等等'+'网卡mac'+'硬盘序列号'"比较的字串.
变换部分清楚了,那剩下的就是找到blowfish计算的key了.
通过对hex串'FA6A1510698C8467'地址设置内存断点跟踪,来到这儿:
005408CD |. 8D4B 38 LEA ECX,DWORD PTR DS:[EBX+38]
005408D0 |. 8D53 38 LEA EDX,DWORD PTR DS:[EBX+38]
005408D3 |. 8BC3 MOV EAX,EBX
005408D5 |. 8B30 MOV ESI,DWORD PTR DS:[EAX]
005408D7 |. FF56 6C CALL DWORD PTR DS:[ESI+6C] blowfish_en
005408DA |. 8BC3 MOV EAX,EBX
005408DC |. 8B10 MOV EDX,DWORD PTR DS:[EAX]
005408DE |. FF52 48 CALL DWORD PTR DS:[EDX+48]
005408E1 |. EB 16 JMP SHORT EsoftPro.005408F9
原来'FA6A1510698C8467'是用blowfish加密64位全零串得到的.那剩下的就是找出key了。
对blowfish的pbox数据地址设置内存访问断点,来到这里:
005408A4 |. 8B4D FC MOV ECX,DWORD PTR SS:[EBP-4] ; |
005408A7 |. 8BC3 MOV EAX,EBX ; |
005408A9 |. E8 1EC0FFFF CALL EsoftPro.0053C8CC ; \检查密钥长度
005408AE |. 8BD7 MOV EDX,EDI
005408B0 |. 8B4D FC MOV ECX,DWORD PTR SS:[EBP-4]
005408B3 |. 8BC3 MOV EAX,EBX
005408B5 |. 8B38 MOV EDI,DWORD PTR DS:[EAX]
005408B7 |. FF57 5C CALL DWORD PTR DS:[EDI+5C] ; 密钥初始化
005408BA |. 85F6 TEST ESI,ESI
005408BC |. 75 25 JNZ SHORT EsoftPro.005408E3
005408BE |. 8D43 38 LEA EAX,DWORD PTR DS:[EBX+38]
005408C1 |. 33C9 XOR ECX,ECX
005408C3 |. BA 08000000 MOV EDX,8
005408C8 |. E8 EF28ECFF CALL EsoftPro.004031BC
005408CD |. 8D4B 38 LEA ECX,DWORD PTR DS:[EBX+38]
005408D0 |. 8D53 38 LEA EDX,DWORD PTR DS:[EBX+38]
得到key是:
'BA0E57F2906C60C62BBB8C7EEBB53B0E'
(in hex)
继续对这个key的地址设置内存断点,分析得到:
005406B1 . 8B53 38 MOV EDX,DWORD PTR DS:[EBX+38]
005406B4 . 8910 MOV DWORD PTR DS:[EAX],EDX
005406B6 . 8D83 8C000000 LEA EAX,DWORD PTR DS:[EBX+8C]
005406BC . 8B53 34 MOV EDX,DWORD PTR DS:[EBX+34]
005406BF . 8910 MOV DWORD PTR DS:[EAX],EDX
005406C1 . 8BC3 MOV EAX,EBX
005406C3 . E8 20F5FFFF CALL EsoftPro.0053FBE8 ; md5
005406C8 . 8BD6 MOV EDX,ESI
005406CA . 8D43 40 LEA EAX,DWORD PTR DS:[EBX+40]
005406CD . B9 10000000 MOV ECX,10
005406D2 . E8 B522ECFF CALL EsoftPro.0040298C
加密key是通过对字符串'作者的名字’做md5计算得到的。
如果有兴趣,也可以看看机器码的计算过程,可以发现,
机器码是对'ghq1978'进行tiger计算,得到key:
'534E72C523DDF7A89079166D71563965547BB63B0B4FCDD4'
(in hex)
然后用这个key,字符串"'ghq1978'+'网卡mac'+'硬盘序列号'"
进行和3处一样的变换,把结果用base64编码输出就是软件显示的机器码.
整个授权文件的验证过程烦了点,主要是那些循环太讨厌了。
但看清楚了过程,要写注册机还是比较简单的。
水平有限,分析得不对的地方,敬请诸位大侠赐教!
by ikki