搜索结果: 1-15 共查到“军事学 HMAC”相关记录16条 . 查询时间(0.046 秒)
Backdoored Hash Functions: Immunizing HMAC and HKDF
hash functions backdoors malicious hashing
2018/4/19
Security of cryptographic schemes is traditionally measured as the inability of resource-constrained adversaries to violate a desired security goal. The security argument usually relies on a sound des...
Exploiting an HMAC-SHA-1 optimization to speed up PBKDF2
HMAC-SHA-1 Password-Based Key Derivation Function 2 Boyar-Peralta heuristic
2018/1/29
PBKDF2 [27] is a well-known password-based key derivation function. In order to slow attackers down, PBKDF2 introduces CPU-intensive operations based on an iterated pseudorandom function (in our case ...
The Exact PRF-Security of NMAC and HMAC
Message authentication codes pseudorandom functions NMAC
2016/1/8
NMAC is a mode of operation which turns a fixed input-length keyed hash function f into a
variable input-length function. A practical single-key variant of NMAC called HMAC is a very popular
and wid...
Equivalent Key Recovery Attacks against HMAC and NMAC with Whirlpool Reduced to 7 Rounds
HMAC NMAC Whirlpool universal forgery
2016/1/4
A main contribution of this paper is an improved analysis against HMAC instantiating with reduced Whirlpool. It recovers equivalent keys, which are often denoted as Kin and Kout, of HMAC with 7-round ...
In this paper, we present universal forgery and key recovery attacks on the most popular
hash-based MAC constructions, e.g., HMAC and NMAC, instantiated with an AES-like hash function
Whirlpool. The...
Generic Security of NMAC and HMAC with Input Whitening
message authentication codes HMAC generic attacks
2015/12/23
HMAC and its variant NMAC are the most popular approaches to deriving a MAC (and
more generally, a PRF) from a cryptographic hash function. Despite nearly two decades of research,
their exact securi...
Symmetric and Dual PRFs from Standard Assumptions: A Generic Validation of an HMAC Assumption
Symmetric Dual PRFs
2015/12/18
The security of HMAC is proven under the assumption that its compression function is a
dual PRF, meaning a PRF when keyed by either of its two inputs. But, not only do we not
know whether particular...
To Hash or Not to Hash Again? (In)differentiability Results for H^2 and HMAC
Indifferentiability hash functions
2014/3/12
We show that the second iterate H^2(M) = H(H(M)) of a random oracle H cannot achieve strong security in the sense of indifferentiability from a random oracle. We do so by proving that indifferentiabil...
Bellare, Canetti and Krawczyk~\cite{FOCS:BelCanKra96} show that cascading an $\eps$-secure (fixed input length) PRF gives an $O(\eps n q)$-secure (variable input length) PRF when making at most $q$ pr...
In this note, we present a full key recovery attack on HMACAURORA-
512 when 512-bit secret keys are used and the MAC length
is 512-bit long. Our attack requires 2257 queries and the off-line complex...
General Distinguishing Attacks on NMAC and HMAC with Birthday Attack Complexity
NMAC HMAC Distinguishing Attack Birthday Attack
2009/1/5
Kim et al. [4] and Contini et al. [3] studied on the security of
HMAC and NMAC based on HAVAL, MD4, MD5, SHA-0 and SHA-1.
Especially, they considered the distinguishing attacks. However, they did
n...
A New Concept of Hash Functions SNMAC Using a Special Block Cipher and NMAC/HMAC Constructions
Hash function NMAC HMAC
2008/12/25
In this paper, we present new security proofs of well-known hash constructions NMAC/HMAC proposed by Bellare et al. in 1996. We show that block ciphers should be used in hash functions in another way ...
Forgery and Partial Key-Recovery Attacks on HMAC and NMAC Using Hash Collisions
Forgery Partial Key-Recovery Attacks HMAC Hash Collisions
2008/12/18
Forgery and Partial Key-Recovery Attacks on HMAC and NMAC Using Hash Collisions.
On Authentication with HMAC and Non-Random Properties
Authentication HMAC Non-Random Properties
2008/12/15
MAC algorithms can provide cryptographically secure authen-
tication services. One of the most popular algorithms in commercial appli-
cations is HMAC based on the hash functions MD5 or SHA-1. In t...
On the Security of HMAC and NMAC Based on HAVAL, MD4, MD5, SHA-0 and SHA-1
HMAC NMAC HAVAL MD4 MD5 SHA-0 SHA-1
2008/11/25
HMAC is a widely used message authentication code and a pseudorandom
function generator based on cryptographic hash functions such as MD5 and SHA-1. It
has been standardized by ANSI, IETF, ISO and N...