搜索结果: 1-15 共查到“HMAC”相关记录19条 . 查询时间(0.078 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 ...
现有基于SM3的HMAC的能量攻击方法，仅适用于同时存在汉明重量和汉明距离信息泄露的攻击对象，如果被攻击对象存在单一模型的信息泄露，则这些方法均不适用。针对该局限性，提出了一种针对SM3的HMAC的能量分析新型攻击方法，该新型攻击方法每次攻击时选择不同的攻击目标和其相关的中间变量，根据该中间变量的汉明距离模型或者汉明重量模型实施能量分析攻击，经过对SM3密码算法的前4轮多次实施能量分析攻击，将攻击...
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...
To Hash or Not to Hash Again?(In)Differentiability Results for H2 and HMAC
Indifferentiability Hash functions HMAC
2012/12/4
We show that the second iterate H2(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 indifferentiabili...
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.