I am working on a project testing a hash that protects some data, and I've already eliminated hash length extension attacks as a possible point of compromise, and I'm trying to educate myself on all the variables.
Say I have some data that is hashed via SHA1 - will knowing parts of that hash (the end piece - basically a known value with an unknown prepended salt) help in breaking the hash/finding the salt at all, other than speeding up a brute force?
By knowing a portion of the hashed data, and the hashed output, would that help in finding the missing, unknown portion of the hashed data? Would it matter if this was hashed using a nonce, and you have multiple versions of the partial data and ending hash? (For example, two hundred hashes, all with the same salt, same known data, changing nonce)
From everything I've read, I BELIEVE the answer to all of the above is "No, it's of no help, you still need to spend years brute forcing it", correct? I just want to cover all my bases before I put faith, and my I'm-no-expert-why-are-you-asking-me seal of approval on/in a security setup I don't have direct control over (If it were up to me I'd HMAC it - but it's not - and I cannot).