Let's say I have an unknown string with the known sha256-hash of it. I was wondering if it was possible to now calculate the sha256 of the concatenation of the unknown string and "abc". (In PHP: ...
I am new in cryptography and I saw this question in a book. I really don't know what this question means and what is the answer of it(it's not my homework etc. but I'd love to know the answer of ...