How and when do I use HMAC? - Information Security Stack Exchange
I was reading HMAC on wikipedia and I was confused about a few points. Where do I use HMAC? Why is the key part of the hash? Even if someone successfully used a "length-extension attack", how …
What is the difference between MAC and HMAC?
Note that HMAC is a specific scheme as Seth correctly describes; SHA-3 uses KMAC which is therefore another hash based MAC. Maybe the acronyms CBMAC and HBMAC could be used for Cipher …
HMAC and integrity - Information Security Stack Exchange
Nov 6, 2019 · All resources that I found online, say only that HMAC guarantee integrity, but I don't understand in what way. I founded this answear here and I understand this : If Alice sends the file …
collision resistance - Why is HMAC-SHA1 still considered secure ...
That said, the construct of HMAC-SHA1 is still considered safe to use (assuming a secret key) due to the security proof for HMAC which does not rely on collision resistance of the underlying PRF.
HMAC Key Sizes for MD5, SHA1, SHA224|256|384|512
SHA512 HMAC uses a ____ bit key and produces a 512 bit digest But I am unable to find definitive key sizes for SHA224, SHA384, and SHA512. The HMAC RFC (2104) lists this: We denote by B the byte …
What's the difference between HMAC-SHA256 (key, data) and SHA256 …
Jan 20, 2015 · Then HMAC is defined as: HASH(Key XOR opad, HASH(Key XOR ipad, text)) or, in detail from the RFC, (Pretext: The definition of HMAC requires a cryptographic hash function, which …
Use cases for CMAC vs. HMAC? - Cryptography Stack Exchange
Apr 22, 2014 · Use cases for CMAC vs. HMAC? Ask Question Asked 11 years, 7 months ago Modified 5 years, 8 months ago
What is the difference between a HMAC and a hash of data?
Please note that "HMAC" is a specific construction of a MAC (from a hash function), and most of your description applies to MACs in general. If we use HMAC-SHA3 or HMAC-SHA512-384, the length …
key generation - What are requirements for HMAC secret key ...
Aug 5, 2015 · HMAC user-input keys that are longer than the specific hash algorithms blocksize are first shortened. (By running the long keys through the hash. And then using that hash as the actual key.) …
hash - HMAC-SHA1 vs HMAC-SHA256 - Cryptography Stack Exchange
I have three questions: Would you use HMAC-SHA1 or HMAC-SHA256 for message authentication? How much HMAC-SHA256 is slower than HMAC-SHA1? Are the security improvements of SHA256 …