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Should file hashes be salted?
A system-wide salt is pointless to mitigate attacks; it would just make passwords longer. A system-wide salt also easily allows an attacker to keep using hash tables. We should hash and salt each password created for a user.
Which is better MAC or hash?
The main difference is conceptual: while hashes are used to guarantee the integrity of data, a MAC guarantees integrity AND authentication.
What is the relationship between a hash and a MAC?
They are two totally different primitives. A MAC is used for message authentication, and is a symmetrically keyed primitive. A hash function can be used for many purposes, and has no special key input. MAC is an acronym of “message authentication code”.
Does a MAC needs a hash function?
only people having the shared key should be able to produce MACs or verify MACs. in particular, it should be unfeasible to produce the MAC of a new message if the MAC of an old message is known. MAC from hash functions MACs are keyed hash functions, so it is natural to use hash functions in a way that uses secret keys.
What’s the difference between salted hash and keyed hashing?
A cryptographic salt is additional input other than message itself for a hash function so that it prevents attacker from launching dictionary attacks. Usually the salt is stored along with the hash of say the password etc. Keyed Hashing is secret key is used as input for hashing along with message like HMAC.
What happens if there is no salt to hash passwords?
Attacker can arrive to conclusion that there’s no salts or using a weak algo to hash the passwords. If they find a lot of the same hashes, sign that server has a default password and every new acct has a default password. The kinds of attacks we’re talking about here are offline attacks against compromised/exfiltrated data.
What happens when you add salt to a hash table?
Consequently, the unique hash produced by adding the salt can protect us against different attack vectors, such as hash table attacks, while slowing down dictionary and brute-force offline attacks. However, there are limitations in the protections that a salt can provide.
What’s the difference between HMAC and a keyed hash?
HMAC is a Message Authentication Code, which is meant for verifying integrity. This is a totally different kind of beast. However, it so happens that HMAC is built over hash functions, and can be considered as a “keyed hash” — a hash function with a key.