OSDev.org

Posted: **Sun Oct 30, 2005 11:34 pm**

Hey guys, on another forum that I am a member of someone posted this challenge.

Decode the following:

30 31 30 30 30 30 20 31 31 30 31 31 30 20 31 31 31 31 30 31 20 31 30 31 31 31 30 20 30 31 31 30 30 31 20 31 31 30 31 31 31 20 30 30 31 30 30 31 20 31 30 30 30 30 31 20 30 31 31 31 30 31 20 30 30 30 31 31 31 20 30 31 30 31 30 31 20 31 30 31 31 30 30 20 30 31 31 30 30 30 20 30 31 30 31 31 31 20 30 31 30 30 30 31 20 31 30 31 30 30 31 20 30 31 31 30 31 31 20 31 31 30 31 31 30 20 31 31 31 30 30 31 20 31 31 30 30 31 31 20 30 30 31 30 31 31 20 30 30 30 30 31 30 20 30 30 30 30 30 31 20 30 31 31 30 30 31 20 30 31 31 30 31 31 20 31 31 30 31 31 31 20 30 31 30 31 30 30 20 31 30 30 30 30 30 20 30 31 31 30 31 30 20 30 30 30 31 31 30 20 30 30 30 31 30 31 20 31 31 30 31 31 30 20 30 31 31 30 30 31 20 30 31 30 30 31 30 20 30 30 30 30 30 31 20 31 30 30 30 31 31 20 30 31 31 31 30 30 20 31 30 30 31 31 30 20 30 30 30 31 30 31 20 31 30 30 30 31 31 20 30 31 31 30 31 30 20 31 31 30 31 31 30 20 30 31 30 31 30 31 20 31 30 30 31 30 30 20 30 30 31 30 30 30 20 30 30 30 31 31 31 20 30 31 30 30 30 31 20 31 30 31 30 30 30 20 30 31 31 30 30 31 20 30 31 30 30 31 30 20 30 30 30 30 30 31 20 31 30 30 31 30 31 20 30 31 31 30 31 31 20 31 30 30 31 31 30 20 30 30 31 31 30 31 20 31 31 30 30 31 30 20 30 31 31 31 31 30 20 30 31 30 31 31 31 20 30 30 30 30 30 31 20 31 31 30 31 30 30 20 30 31 31 30 31 30 20 30 31 30 31 31 30 20 31 31 31 31 30 31 20 31 30 31 31 31 30 20 30 30 31 30 30 30 20 30 31 30 30 31 30 20 30 30 30 30 30 31 20 30 30 31 30 30 30 20 30 31 31 30 30 31 20 30 31 30 31 31 31 20 30 30 31 30 30 31 20 31 30 30 31 30 31 20 30 30 31 30 30 30 20 30 30 30 31 31 30 20 31 30 30 31 30 31 20 31 31 30 30 31 31 20 30 30 31 30 30 30 20 30 30 30 31 31 31 20 31 30 30 31 30 31 20 31 30 31 31 31 31 20 30 31 31 31 30 31 20 30 31 30 31 31 31 20 30 30 31 30 30 30 20 31 30 30 30 30 30 20 30 31 31 30 30 30 20 30 31 30 31 31 30 20 31 31 31 30 30 31 20 31 31 30 30 31 31 20 30 31 31 31 30 31 20 31 31 30 31 31 30 20 30 31 30 31 30 31 20 31 31 30 30 31 30 20 30 30 31 31 31 30 20 31 30 30 30 31 30 20 30 30 30 30 30 31 20 30 31 31 30 30 30 20 30 31 31 30 30 31 20 31 30 30 31 31 31 20 30 30 30 30 30 31 20 31 31 30 31 30 30 20 30 31 30 31 30 30 20 31 30 30 30 31 31 20 30 30 31 31 30 31 20 31 31 30 30 31 30 20 30 31 31 31 30 31 20 30 30 30 30 31 31 20 30 31 30 31 30 31 20 30 31 30 30 31 31 20 30 30 31 31 31 30 20 30 30 30 31 31 30 20 30 31 31 31 30 31 20 31 30 31 31 30 30 20 30 30 31 31 30 30 20 31 30 30 30 31 31 20 30 30 30 31 30 30 20 31 31 30 31 30 30 20 30 31 31 30 30 31 20 31 30 30 31 31 30 20 31 30 31 31 30 31 20 31 30 30 31 31 30 20 30 31 30 30 30 31 20 30 30 30 31 31 30 20 31 30 31 31 30 31 20 30 30 30 31 30 30 20 30 30 31 31 30 31 20 31 31 30 30 31 31 20 30 31 31 31 30 31 20 31 30 30 30 31 31 20 30 31 31 31 30 30 20 31 30 30 30 31 31 20 30 30 30 30 30 31 20 31 31 31 30 31 30 20 30 31 30 31 31 30 20 31 30 00

HINTS:
1. Writing a program may help you.
2. There are eight bits in one byte.
3. Think low level, very low level.

I have absolutely no clue how to go about solving this, and you people are among some of the most intelligent programmers I know, so I thought you might enjoy trying to solve this one for me.

Posted: **Sun Oct 30, 2005 11:54 pm**

't Looks like it's got to be solved like this:
Convert hex->Ascii
Then you'll have an array of 0s, 1s and spaces (30 = 0, 31 = 1, 20 = space) These make me think you'll have to concider this as binary and convert that to either numbers or text. That every space is the 7th value on row makes me think this even more.

Of course I could be way off. I'm tired as hell ('t Is nearly 7am now), but at least that's my two cents.

Posted: **Mon Oct 31, 2005 2:10 am**

cloudee1 wrote: I have absolutely no clue how to go about solving this, and you people are among some of the most intelligent programmers I know, so I thought you might enjoy trying to solve this one for me.

No, of course not. We're very lazy here, all we do is write operating systems. We're not very sportive or competitive, I don't think you'll find many people actually interested in the competition.

As said before, they're space-separated binary digits, not balanced (they finish at a non-byte end). Make a few programs that try to decode it (first try to make it plain ascii etc.) and look at the output for patterns.

Posted: **Mon Oct 31, 2005 3:36 am**

*yawn* I rather enjoy a fight with a big power spring than solving puzzles *for others* *chuckle*

Indeed, we here are kinda lazy folks,eh? writing opsys an' nothin' more, I reckon, isn't a garuntee for being eager to do decoding stuff. *gg*

Posted: **Mon Oct 31, 2005 8:49 am**

"Congratulations, You have cracked the encryption! Here is your answer: XfptR3rt5S8gl214fkfDkD77cr0zZ"
Didn't take me more than 5 minutes.
Oh, and it does divide into bytes nicely, the last symbol happens to be null-termination of the string, with spaces thrown in it to distract everyone (except for me

).

Posted: **Mon Oct 31, 2005 9:40 am**

Here, here, I know one:

"qedfh23890hvphv894hfnhwjsl"

I'll even tell you how it's encrypted: I used a One-Time-Pad.

;D

Posted: **Mon Oct 31, 2005 10:09 am**

Ah, I failed to decrypt it with a first glance, but I did discover what you meant by it.

Posted: **Fri Nov 04, 2005 3:33 am**

Finally got it. Took me ~10 mins to get my binary to string function working, though. Enjoy some badly written code

Code: Select all

void bin2string(char * bin)
{   
   int shift = 0;
   int temp =0;
   int counter = 0;
   unsigned char ret = 0;
   int i;
   
   int table[] = {128, 64, 32, 16, 8, 4, 2, 1};

   while(bin[counter] != '\0')
   {
      for(i=0; i<8; i++)
      {
         //skip over space characters
         if(bin[(i + shift) + counter] == 0x20) {
            shift++;
         }
         
         //get intermediate value
         temp += (bin[(i + shift) + counter] - '0') * table[i];
         
         //set return value
         ret = temp;
      }
      
      cout << ret;
      counter += (i + shift);
      temp = 0;
      shift=0;
      i=0;
   }
}

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