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 …
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 …
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.) …
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 …
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 …
What is the difference between a HMAC and a hash of data?
On a recent question it became apparent that there's a significant difference between an HMAC of input data and a hash of input data. What exactly is the difference between an HMAC and a hash of ...
HMAC: IV=key instead of concatenation? - Cryptography Stack Exchange
Dec 24, 2024 · NMAC has two independent keys. However note that what HMAC does is that it passes two different versions of the key through the hash function. If we assume a hash function is a secure …
When do I need to use CBC and HMAC? - Cryptography Stack Exchange
Aug 13, 2018 · As I know CBC does not provide integrity for the message, thus HMAC is used to provide integrity for CBC message. Also, I hear about CBC-MAC which can provide integrity and …