XXDownload1.14分析（注意版本） (5千字)
from DEDE we got the info below:--------------------------------
005A1F1D E84224E6FF call 00404364 ; cat MC behind NAME and a '-', and form a long STRING
005A1F22 8B45EC mov eax, [ebp-$14]
005A1F25 5A pop edx
005A1F26 E859180300 call 005D3784 ; here is the main call for CODE
005A1F2B 84C0 test al, al
let's deep into CALL 5D3784, and see what is in it:
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005D37C8 8B45FC mov eax, [ebp-$04] ; here is the long STRING
005D37CB E848000000 call 005D3818 ; some kind calculation
005D37D0 8B45F0 mov eax, [ebp-$10] ; the result CODE
005D37D3 8B55F8 mov edx, [ebp-$08] ; the input CODE
* Reference to: system.@LStrCmp;
005D37D6 E8D90BE3FF call 004043B4
005D37DB 7506 jnz 005D37E3 ; FAILED!
see what is in CALL 005D3818:
-----------------------------
005D3851 |. 8D4D D8 LEA ECX,DWORD PTR SS:[EBP-28]
005D3854 |. BA B8385D00 MOV EDX,unpacked.005D38B8 ; ASCII "hidownload1.14"
005D3859 |. 8B45 FC MOV EAX,DWORD PTR SS:[EBP-4] ; Long STRING
005D385C |. E8 8FDF0000 CALL unpacked.005E17F0 ; step 1()
result1 is: 'ylUQQbbOCBkVHn7X/POg+V/BefqmnRucVd3yORd/xh=='
005D3861 |. 8B45 D8 MOV EAX,DWORD PTR SS:[EBP-28] ; result1
005D3864 |. 8D55 DC LEA EDX,DWORD PTR SS:[EBP-24]
005D3867 |. E8 4037FAFF CALL unpacked.00576FAC ; step 2()
result2 is: 92 B6 9C FE 3A 66 FE 95 7C 11 C0 AD 28 2B 6C F1 128bits
005D386C |. 8D45 DC LEA EAX,DWORD PTR SS:[EBP-24] ; result2
005D386F |. 8B55 F8 MOV EDX,DWORD PTR SS:[EBP-8]
005D3872 |. E8 A937FAFF CALL unpacked.00577020 ; step 3(change result2 to a HEX string)
; the HEX string is the right code
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see step 1 in CALL 005E17F0 first:
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005E182A |. A1 F8C85400 MOV EAX,DWORD PTR DS:[54C8F8]
005E182F |. E8 9CB1F6FF CALL unpacked.0054C9D0 ; BlowFish.Create
005E1834 |. 8945 F0 MOV DWORD PTR SS:[EBP-10],EAX ; store BlowFish
005E1837 |. 8B55 F8 MOV EDX,DWORD PTR SS:[EBP-8]
005E183A |. 8B45 F0 MOV EAX,DWORD PTR SS:[EBP-10]
005E183D |. E8 1EAFF6FF CALL unpacked.0054C760
CALL unpacked.0054C760:
-----------------------
0054C76C |. A1 C0BD5400 MOV EAX,DWORD PTR DS:[54BDC0]
0054C771 |. E8 06F7FFFF CALL unpacked.0054BE7C ; SHA1.Create
0054C776 |. 8BD8 MOV EBX,EAX
0054C778 |. 8BC3 MOV EAX,EBX
0054C77A |. 8B10 MOV EDX,DWORD PTR DS:[EAX]
0054C77C |. FF52 34 CALL NEAR DWORD PTR DS:[EDX+34]; SHA1.Initial values(0x67452301...)
0054C7B0 |. 8B08 MOV ECX,DWORD PTR DS:[EAX] ; 'hidownload1.14'
0054C7B2 |. FF51 40 CALL NEAR DWORD PTR DS:[ECX+40]; SHA1.Encrypt
SHA1('hidownload1.14') = FD BD AD D9 20 79 52 03 2A 24 0B AE 48 E7 ED 7E F0 28 6A 8B
0054C7D0 |. 8BD6 MOV EDX,ESI
0054C7D2 |. 8BCD MOV ECX,EBP
0054C7D4 |. 8BC7 MOV EAX,EDI
0054C7D6 |. 8B38 MOV EDI,DWORD PTR DS:[EAX]
0054C7D8 |. FF57 30 CALL NEAR DWORD PTR DS:[EDI+30]; BlowFish_Init(SHA1.result)
; BlowFish_EN(-1)
005E1867 |. 8BD0 MOV EDX,EAX
005E1869 |. 8B45 F0 MOV EAX,DWORD PTR SS:[EBP-10]
005E186C |. 59 POP ECX
005E186D |. 8B18 MOV EBX,DWORD PTR DS:[EAX]
005E186F |. FF53 4C CALL NEAR DWORD PTR DS:[EBX+4C] ; Loops of BlowFish_EN xor long STRING
; if U want to know more, just track in
005E1875 |. 8B45 EC MOV EAX,DWORD PTR SS:[EBP-14] ; result of last op
005E1878 |. E8 FBA2F6FF CALL unpacked.0054BB78 ; something like base64
'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
005E187D |. 8B55 E8 MOV EDX,DWORD PTR SS:[EBP-18] ; result of last op
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then see step 2 in CALL 00576FAC next:
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00576FCE |. 8D45 A0 LEA EAX,DWORD PTR SS:[EBP-60]
00576FD1 |. E8 1AFEFFFF CALL unpacked.00576DF0 ; MD5.Initial
00576FED |. E8 52FEFFFF CALL unpacked.00576E44 ; grouped result1
00576FF2 |. 8B55 F8 MOV EDX,DWORD PTR SS:[EBP-8]
00576FF5 |. 8D45 A0 LEA EAX,DWORD PTR SS:[EBP-60]
00576FF8 |. E8 1FFFFFFF CALL unpacked.00576F1C ; MD5.Encrypt
; it is the result2
In HiDownLoad1.15 it still use visible code compare:), but how to get the code changed:
Name + ':' + EMail + 'chs-1.15'
MD5
change MD5's to string
