reply on: Need help recovering wallet from 2010 \ stacker news ~bitcoin

1211 sats \ 7 replies \ @jimmysong 30 Aug 2023 \ on: Need help recovering wallet from 2010 bitcoin

It's almost certainly Bitcoin Core, though I don't know why it would give the hexadecimal of the private key. That's a fairly unusual format for a private key to be in. That said, it's easy enough to write a script to try some combination of your 66 hex characters and convert it to a 32-byte private key. The WIF format has 4 bytes extra (for a total of 36 bytes or 72 hex characters) that act as a checksum, though that's encoded in Base58, so it's unlikely to be that.

Honestly, you're best off hiring someone with the 1 BTC bounty as part of it. You'll be able to tell onchain if the person lied to you and just took the bitcoin.

1765 sats \ 6 replies \ @jennann OP 30 Aug 2023

Thanks Jimmy. Big fan of your writing. I think a script is a good idea.

Below is the exact format including the location of the question marks, but I did change each character to something random and different than the original. When I get off work later I will try adding the 0x in front of each side, but still unsure of significance of the question marks. At first I wasn't sure if I had two 40 character length keys, or one 66-80 character keys Not sure why question marks would only be in half the writing.

0486 | 4AE5F | 41BC A58F | 3FB3A | 1AD7

34F6 | 2AEB9 37A4 | 4AE5F

7?A4 | ?42? | 6F?? | ??D8 71?D | 6?A? | ?FCA | 86B?

32?F 7F?B

0 sats \ 5 replies \ @jimmysong 30 Aug 2023

The really odd thing here is the 5-letter hex found in the second column of the first 4 lines. Hex almost always come in pairs as each byte is 8 bits and each hex letter is 4 bits.

So doing some math 15 bytes in first chunk, 9 bytes, second chunk. 16 bytes third chunk, 4 bytes fourth chunk. 40 bytes is too much for a private key (they're 32 bytes) and 24 could be it, I guess. I can write you a script that you can run to check if the 24 bytes come out to the address you were looking at. I'm guessing it's uncompressed SEC since it's so early, and that's a detail you're going to need to know about for address generation. DM me on Twitter if you want to try it.

0 sats \ 4 replies \ @jennann OP 30 Aug 2023

Sorry, that was an accident when writing the example. Every block is only four characters. How does that change things?

The only other thing I can think about if nothing else works, is I took the Bitcoin Core backup it gave me and converted it into to HEX, so if someone found it they wouldn't know what is was.

We hear all about these examples now, but I wasn't aware of those risks back then.

10 sats \ 3 replies \ @jimmysong 30 Aug 2023

12 bytes/8 bytes/16 bytes/4 bytes

There's no obvious way to get 32 bytes, which is the typical length of a private key. I guess it could be that the last 4 bytes are not anything and the first 3 chunks are 32 bytes + 4 byte checksum. If it were and you had those question marks in those places, that's 10 question marks or 40 bits that you have to roll through or 2^40 of attempts. That's about a trillion different possibilities, which is doable, especially with some GPUs. I did 2^44 in about 2 days a while back and that cost about $800 to rent the requisite GPUs if I remember correctly. So, 2^40 should be 1/16th of that, or 3 hours and $50? But there's some custom code that needs to be written to calculate the address and there's no guarantee that that's what these letters mean.