hello guys,please help me this loop................

[diskgetor]

8C7A:canstants

now you known this:

char [10]={7A D0 07 71 DE 82 5F 40 AA 13}

next is the cacl:

78787879 imul  7A=00000039:696969AA  //get char[0]

39 SAR 3=7

7A ADD 7=81

8C7A ADD 81=8CFB

78787879 imul  8CFB=00004258:00004AA3

4258 SAR 3=084B

084B ADD 8CFB=9546

78787879 imul  D0=00000061:E1E1E250  //get char[1]

61 SAR 3=0C

D0 ADD 0C=DC

9546 ADD DC=9622

78787879 imul  9622=000046A6:9696E612

46A6 SAR 3=08D4

08D4 ADD 9622=9EF6//D0

78787879 imul 07=00000003:4B4B4B4F  //get char[2]

3 SAR 3=0

07 ADD 0=07

9EF6 ADD 7=9EFD

78787879 imul  9EFD=00004AD1:6969BD95

4AD1 SAR 3=095A

095A ADD 9EFD=A857//07

78787879 imul  71=00000035:2D2D2D69  //get char[3]

35 SAR 3=6

71 ADD 6=77

A857 ADD 77=A8CE

78787879 imul  A8CE=00004F70:0000595E

4F70 SAR 3=09EE

09EE ADD A8CE=B2BC//71

78787879 imul  DE=00000068:787878EE  //get char[4]

68 SAR 3=0D

DE ADD 0D=EB

B2BC ADD EB=B3A7

78787879 imul  B3A7=0000548A:D2D331EF

548A SAR 3=0A91

0A91 ADD B3A7=BE38//DE

78787879 imul  82=0000003D:2D2D2D72  //get char[5]

3D SAR 3=07

82 ADD 07=89

BE38 ADD 89=BEC1

78787879 BEC1  BEC1=000059C4:3C3CA139

59C4 SAR 3=0B38

0B38 ADD BEC1=C9F9//82

78787879 imul  5F=0000002C:B4B4B4E7  //get char[6]

2C SAR 3=05

5F ADD 05=64

C9F9 ADD 64=CA5D

78787879 imul  CA5D=00005F3A:D2D33DF5

5F3A SAR 3=0BE7

CA5D ADD 0BE7=D644

78787879 imul  40=0000001E:1E1E1E40  //get char[7]

1E SAR 3=03

40 ADD 03=43

D644 ADD 43=D687

78787879 imul  D687=000064F4:3C3CADCF

64F4 SAR 3=0C9E

0C9E ADD D687=E325//40

78787879 imul  AA=00000050:0000005A  //get char[8]

50 SAR 3=0A

AA ADD 0A=B4

E325 ADD B4=E3D9

78787879 imul  E3D9=00006B38:F0F16991

6B38 SAR 3=0D67

E3D9 ADD 0D67=F140//AA

78787879 imul  13=00000008:F0F0F0FB  //get char[9]

08 SAR 3=01

13 ADD 01=14

F140 ADD 14=F154

78787879 imul  F154=00007190:F0F170B4

7190 SAR 3=0E32

0E32 ADD F154=FF86//13

take the last add:FF86 CACL this:

FF86 sar 8=FF

FF86 sar 3=1FF0

F0 XOR FF=0F

0F XOR 86=89

--------------------------------------------------------------

89^ 13=9A

89^ AA=23

89^ 40=C9

89^ 5F=D6

89^ 82=0B

89^ DE=57

89^ 71=F8

89^ 07=8E

89^ D0=59

89^ 7A=F3

F3598EF8570BD6C9 //get this char[10]

--------------------------------------------------------

now ,i Hypothesis you know char[10]=[F3598EF8570BD6C9],how do you cacl :

char [10]={7A D0 07 71 DE 82 5F 40 AA 13} form C language?i was uesd vc++6.0  .thanks all.please give me some Suggestions ETC.

Edited May 29, 2014 by diskgetor

[Nemo]

Reverse the code...(add to sub .. etc in reverse.. little brute forcing with the xors though..  

[UniSoft]

Here is your algo in c 

unsigned int i;

unsigned short k;

unsigned char buf[] = {0x7A,0xD0,0x07,0x71,0xDE,0x82,0x5F,0x40,0xAA,0x13};
k = 0x8C7A;

for (i = 0; i < sizeof(buf); i++) {

    k += buf[i] + buf[i] / 0x11;

    k += k / 0x11;

}

k = (k >> 3) ^ (k >> 8) ^ 0x86;
for (i = 0; i < sizeof(buf); i++) {

    buf[i] ^= (unsigned char)k;

}

[diskgetor]

ok,this bug was fixed,thanks UniSoft.