Thread: Aika Bin files encryption-decryption

Aika Online .bin encryption-decryption

Some of the Aika .bin files are encrypted. Here are cipher tables, asm functions and C/Delphi codes for encryption and decryption those files. You can examine them all and try to find something interesting.

P.S. if it necessary I can make a small app for automatization of (de)encryption process

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ItemList%.bin
UI/PI.bin

EDI - length of decryption array
Algorithm

 004058CE  |> /8BC1          /MOV EAX,ECX

004058D0  |. |8A99 80B43401 |MOV BL,BYTE PTR DS:[ECX+134B480]  ; byte from file

004058D6  |. |99            |CDQ

004058D7  |. |F7FF          |IDIV EDI

004058D9  |. |8A92 54565E00 |MOV DL,BYTE PTR DS:[EDX+5E5654]   ; load byte from table

004058DF  |. |02D1          |ADD DL,CL                         ; add counter value

004058E1  |. |2ADA          |SUB BL,DL                         

004058E3  |. |8899 80B43401 |MOV BYTE PTR DS:[ECX+134B480],BL  ; write new byte to the buffer

004058E9  |. |41            |INC ECX                           

004058EA  |. |81F9 00405600 |CMP ECX,00564000               ; cmp with file length      

004058F0  |.^7C DC         JL SHORT 004058CE 

cipher table

Code:

 BE C6 C0 CC C5 DB 20 B8 AE BD BA C6 AE 20 C0 CE
C4 DA B5 F9 20 B7 E7 C6 BE C0 D4 B4 CF B4 D9 2E
20 B7 EA B7 E7 20 B6 F6 B6 F3 2E 2E 2E 20 C0 B8
2E 2E 2E 20 C1 A4 B8 BB 20 C1 A4 B8 BB 20 B1 CD
C2 FA B4 D9 2E 20 B1 D7 B7 A1 B5 B5 20 C7 D8 BE
DF C7 CF B4 CF 20 BE EE C2 BF 20 BC F6 20 BE F8
C1 D2 2E 2E 2E 20

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SkillData%d.bin
UI/Recipe.bin
UI/ReinforceW01.bin
UI/Reinforce2.bin
UI/Reinforce3.bin
UI/Easing.bin
UI/Siege01.bin
UI/Siege02.bin
UI/BW.bin
UI/MakeItems.bin

Algorithm same as above

cipher table

Code:

 C0 CC B0 C5 20 C0 D0 C1 F6 20 B8 B6 BC BC BF E4
2E 20 C0 D0 C0 B8 B8 E9 20 B3 AA BB DB BB E7 B6
F7 B5 CB B4 CF B4 D9 2E 20 C1 A6 B9 DF 20 C0 FD
B4 EB 20 C0 D0 C1 F6 B8 BB B0 ED 20 C2 F8 C7 D1
20 BB E7 B6 F7 B5 EE B7 CE 20 BB E7 BC BC BF E4
2E 20 BE C6 BC CC C1 D2 3F 20 C1 C1 C0 BA BC BC
BB F3 B8 B8 B5 EC BD C3 B4 D9 2E

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UI/curse.bin

 00423468  |> /8A88 300EC101 /MOV CL,BYTE PTR DS:[EAX+1C10E30]

0042346E  |. |40            |INC EAX

0042346F  |. |F6D1          |NOT CL

00423471  |. |8888 2F0EC101 |MOV BYTE PTR DS:[EAX+1C10E2F],CL

00423477  |. |3D 00000100   |CMP EAX,10000

0042347C  |.^72 EA         JB SHORT 00423468 

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UI/MN.bin

 00420052  |> /8A88 50D8AF01 /MOV CL,BYTE PTR DS:[EAX+1AFD850]

00420058  |. |2AC8          |SUB CL,AL

0042005A  |. |8888 50D8AF01 |MOV BYTE PTR DS:[EAX+1AFD850],CL

00420060  |. |40            |INC EAX

00420061  |. |3D 00000400   |CMP EAX,40000

00420066  |.^7C EA         JL SHORT 00420052 

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C, Delphi code example

 v4 = 0;

    do

    {

      dword_134B480[v4] -= (_BYTE)v4 + byte_5E5654[v4 % (signed int)(strlen(byte_5E5654) - 1)];

      v4++;

    } 

 decryption

   for j:=0 to length(Buffer) - 1 do

      buffer[j] := buffer[j] - (cipherTable[j mod cipherLength] + j);



encryption

   for j:=0 to length(Buffer) - 1 do

      buffer[j] := buffer[j] + (cipherTable[j mod cipherLength] + j); 

© Dwar

SkillData.bin + ItemList.bin structure: https://progamercity.net/game-files/...structure.html