Game: First person to crack this gets 5 BTC [SOLVED]

[BTCurious]

Gratz. Can you explain how?
It's obviously base64-encoded now. Decoding that, and then encoding in base58 gave me something that began with a 5, which looked like a private key wallet import format, but it was too long…

[1715288801]

1715288801

[1715288801]

1715288801

[1715288801]

1715288801

[1715288801]

1715288801

[Ean]

I updated the last post with an explanation.

[BTCurious]

Wow. How the hell did you figure that out?

[bulanula]

I updated the last post with an explanation.

Looks like the coins are out already LOL.

Is that ( 1QE6bWhqizxUVuq55GjL1SErVKH9YCHb7e ) your address ?

[Ean]

The base64-decoded string was too long to be a binary key and too short to be a base58-enkoded key. I had the idea that it somehow involved 7 bit ascii values. That yielded a key starting with 6 and that contained colons ...

I updated the last post with an explanation.

Looks like the coins are out already LOL.

Is that ( 1QE6bWhqizxUVuq55GjL1SErVKH9YCHb7e ) your address ?

Yes.

[BurtW]

Very nice.  The base64 looked pretty obvious to me also that is why I considered myself 1/3 the way there.  Didn't see the ascii thing.  Well played.

[mb300sd]

Congratulations, I didn't think anyone would figure it out that fast. 

I'll post another one of these later today or tomorrow.

Here was my original encoding code:

Code:

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;

namespace ConsoleApplication1
{
	class Program
	{
		static void Main(string[] args)
		{
			/*
			 Address: 1FezVeQ2unSiCbKwP9UArahNoMwaprCAyJ
			 Privkey: 5JWLNT79k1Ao4yk1j9fj5zQNRuEVrpUi4hsn2v8oFNfTjPM8Wqf
			 */
			String key = "5JWLNT79k1Ao4yk1j9fj5zQNRuEVrpUi4hsn2v8oFNfTjPM8Wqf";
			String inc = ""; 

			for (int i = 0; i < key.Length; i++)
			{
				 inc += (char)((byte)key[i] + 1);
			}
			key = inc;
			inc = "";

			byte[] bytes = Encoding.ASCII.GetBytes(key);

			BitArray bits = new BitArray(bytes);
			int bit7len = (bits.Length / 8) * 7;
			while (bit7len % 8 != 0)
			{
				bit7len++;
			}
			BitArray bit7 = new BitArray(bit7len);

			int j = 0;
			int k = 0;
			foreach (bool bit in bits)
			{
				if (j != 7)
				{
					bit7[k] = bit;
					k++;
				}
				j++;
				if (j == 8) j = 0;
			}

			byte[] ret = new byte[bit7.Length / 8];
			bit7.CopyTo(ret, 0);

			Console.WriteLine(Convert.ToBase64String(ret));

			Console.ReadLine();
		}
	}
}

[scintill]

Dang, I was just starting to think about different bit encodings, don't know if I would have gotten it that quickly though.  Good job, and looking forward to another round!

Cool to see the code from mb300sd too, btw, thanks.

[ineededausername]

Grats! Nice puzzle

[NASDAQEnema]

dammit - I practically guessed the model from the fact he said it was encoded not encrypted.

I hate being sick. Can't code challenges :/