It absolutely could be brute forced, we litrally have the hash of the chunk. I’ve thought about it before too, if one seeder is constantly giving, or refusing to even give, the chuck because of the hash mismatch, odds are it’s only a bit flipped somewhere.
Another option that I’ve done before is find the file elsewhere, and switch it out. Seed for a long time then, you weren’t the only person at 99.9%.
SHA1 has a fairly even distribution, it produces 160 bit digests, so each possible variation of a chunk will have a roughly 2-160 probability to hit your hash. Now assuming you have some insane computing device that can do an exahash per hour (that’s 1018 hashes, a lot more than any modern hardware can do), finding one would take around 1.7E+26 years. Now the funniest part. Assuming your chunk is 32KiB large (practically nobody uses such small chunks today, so it’s the best-case scenario), there are 2^(32×210×23)/2160 possible variations of the chunk that would produce your exact hash. That’s roughly 1.1E+78865 fitting chunks with only one being correct. And it takes you 1.7E+26 years to get to just one of them.
It absolutely could be brute forced, we litrally have the hash of the chunk. I’ve thought about it before too, if one seeder is constantly giving, or refusing to even give, the chuck because of the hash mismatch, odds are it’s only a bit flipped somewhere.
Another option that I’ve done before is find the file elsewhere, and switch it out. Seed for a long time then, you weren’t the only person at 99.9%.
SHA1 has a fairly even distribution, it produces 160 bit digests, so each possible variation of a chunk will have a roughly 2-160 probability to hit your hash. Now assuming you have some insane computing device that can do an exahash per hour (that’s 1018 hashes, a lot more than any modern hardware can do), finding one would take around 1.7E+26 years. Now the funniest part. Assuming your chunk is 32KiB large (practically nobody uses such small chunks today, so it’s the best-case scenario), there are 2^(32×210×23)/2160 possible variations of the chunk that would produce your exact hash. That’s roughly 1.1E+78865 fitting chunks with only one being correct. And it takes you 1.7E+26 years to get to just one of them.
Yea, I wouldn’t say that.
This is why recovery info for archives is a boon - sadly it’s pretty out of fashion.
This should be the next cryptocurrency proof of work algorithm
Bitcoin uses two rounds of SHA256 if I recall correctly.