4 ms·

We don't store any checksums - we just store your files. The checksum commands: (md5, sha1, sha224, sha256, sha384, sha512, sha512t256, rmd160, skein256, skei

• derefr 4y ago
  I think you misinterpreted the comment you're responding to; they meant that "sadly, you [the user] never thought to store a high-quality hash (e.g. SHA256) for integrity comparison with your stored data; and the hash you did decide to archive for integrity-comparison was a low-quality one (e.g. MD5) that can be trivially preimage-attacked such that a cloud provider could silently replace your data with a different one — with the same low-quality hash — without your knowledge." Nothing about rsync.net per se, other than the general idea that any data you put on "somebody else's server" can't be trusted to stay the same if you don't have a high-quality integrity-comparison content-hash of that data kept somewhere.
  • userbinator 4y ago
    MD5 still has no known preimage attacks. Neither does MD4, for which collisions are absolutely trivial to generate.
    • a1369209993 4y ago
      To be fair, it may yet turn out that MD5 is (and has always been, we just didn't know it yet) a low-quality hash that can be trivially preimage-attacked. I think that's unlikely[0], but I can easily imagine someone reasonable being a bit more pessimistic. I certainly wouldn't willingly rely on MD5 preimage resistance for anything important. 0: I'd be willing to bet money at 1:1 odds that MD5 preimages still cost at least 2^96 bit operations (out of a nominal 2^127 hash invocations) 5, 20, or 100 years from now.