[Keygenme] Ch#1

Posted January 5, 201015 yr

Find correct serial/s

ch01.zip

January 7, 201015 yr

Huh... i wrote a cracker for this and it was working for 1hour

but brute forcing a serial for this is near to impossible!

will try again

January 9, 201015 yr

**deleted due to grave thinking mistake**

Damn, it`s imul... :/ :/

Edited January 9, 201015 yr by deepzero

January 9, 201015 yr

interesting keygenme, hard!

Edited January 9, 201015 yr by fenoloji

January 9, 201015 yr

not hard

~30 min - for write bruter

~20 min - for brute

correct serials:

A69D43CF

FA0CF945

bruter code, on delphi:


procedure frmMain.Brute;
var
  res, i, n, c_: dword;
begin
  Memo1.Clear;
  c_ := $0;
  while true do
  begin
    Application.ProcessMessages;
    res := $811C9DC5;
    for i := 7 downto 0 do
    begin
      n := c_ shr (4 * i) and $F;
      if n in [0..9] then
        n := n + $30
      else
        n := n + $37;
      res := (res xor n) * 16777619;
    end;
    if res = $D825C8DF then
      Memo1.Lines.Add(IntToHex(c_, 8));    inc(c_);
    if c_ = $FFFFFFFF then
      break;
  end;
end;

1

January 10, 201015 yr

I congratulate.

Edited January 10, 201015 yr by fenoloji

January 11, 201015 yr

Author

not hard
correct serials:
A69D43CF
FA0CF945
....

congratz. good solution.

my solution in C++:


#include "stdafx.h"
#include "time.h"int _tmain(int argc, _TCHAR *argv[])
{
  /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
  char    *table="0123456789ABCDEF";
  char    key[]="00000000";
  time_t  start,
          finish;
  double  elapsed_time;  int     serno=1;
  /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/  time(&start);
  for (unsigned int a=0; a < 16; a++)
  {
    key[0]=table[a];    for (unsigned int b=0; b < 16; b++)
    {
      key[1]=table[b];      for (unsigned int c=0; c < 16; c++)
      {
        key[2]=table[c];        for (unsigned int d=0; d < 16; d++)
        {
          key[3]=table[d];          for (unsigned int e=0; e < 16; e++)
          {
            key[4]=table[e];            for (unsigned int f=0; f < 16; f++)
            {
              key[5]=table[f];              for (unsigned int g=0; g < 16; g++)
              {
                key[6]=table[g];                for (unsigned int h=0; h < 16; h++)
                {
                  key[7]=table[h];                  unsigned int  hash=0x811C9DC5;
                  for (unsigned int i=0; i < 8; i++)
                  {
                    hash^= (unsigned char) key[i];
                    hash*=0x1000193;
                  }                  if (hash == 0xD825C8DF)
                  {
                    time(&finish);
                    elapsed_time=difftime(finish,start);
                    elapsed_time/=60;
                    printf("Correct key #%d is:",serno);
                    printf("%s -> %6.2f mins.\n",key,elapsed_time);
                    serno+=1;
                  };
                }
              }
            }
          }
        }
      }
    }
  }  time(&finish);
  elapsed_time=difftime(finish,start);
  elapsed_time/=60;
  printf("All serials bruted for %6.2f mins.\n",elapsed_time);  char  ch;
  scanf_s(" %c",&ch);  return 0;
}