Randomness Analyses of the Secure Hash Algorithms, SHA-1, SHA-2 and Modified SHA
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PHC: Status Quo
PHC: status quo JP Aumasson @veorq / http://aumasson.jp academic background principal cryptographer at Kudelski Security, .ch applied crypto research and outreach BLAKE, BLAKE2, SipHash, NORX Crypto Coding Standard Password Hashing Competition Open Crypto Audit Project board member do you use passwords? this talk might interest you! Oct 2013 "hash" = 3DES-ECB( static key, password ) users' hint made the guess game easy... (credit Jeremi Gosney / Stricture Group) May 2014; "encrypted passwords" (?) last week that's only the reported/published cases Lesson if Adobe, eBay, and Avast fail to protect their users' passwords, what about others? users using "weak passwords"? ITsec people using "weak defenses"? developers using "weak hashes"? cryptographers, who never bothered? agenda 1. how (not) to protect passwords 2. the Password Hashing Competition (PHC) 3. the 24-2 PHC candidates 4. next steps, and how to contribute WARNING this is NOT about bikeshed topics as: password policies password managers password-strength meters will-technology-X-replace-passwords? 1. how (not) to protect passwords solution of the 60's store "password" or the modern alternative: obviously a bad idea (assuming the server and its DB are compromised) solution of the early 70's store hash("password") "one-way": can't be efficiently inverted vulnerable to: ● efficient dictionary attacks and bruteforce ● time-memory tradeoffs (rainbow tables, etc.) solution of the late 70's store hash("password", salt) "one-way": can't be efficiently inverted immune to time-memory tradeoffs vulnerable to: ● dictionary attacks and bruteforce (but has to be repeated for different hashes) solution of the 2000's store hash("password", salt, cost) "one-way": can't be efficiently inverted immune to time-memory tradeoffs inefficient dictionary attacks and bruteforce main ideas: ● be "slow" ● especially on attackers' hardware (GPU, FPGA) => exploit fast CPU memory access/writes PBKDF2 (Kaliski, 2000) NIST and PKCS standard in Truecrypt, iOS, etc. -
Hello, and Welcome to This Presentation of the STM32MP1 Hash Processor
Hello, and welcome to this presentation of the STM32MP1 hash processor. 1 Hash peripheral is in charge of efficient computing of message digest. A digest is a fixed-length value computed from an input message. A digest is unique - it is virtually impossible to find two messages with the same digest. The original message cannot be retrieved from its digest. Hash digests and Hash-based Message Authentication Code (HMAC) are widely used in communication since they are used to guarantee the integrity and authentication of a transfer. 2 HASH1 is a secure peripheral (under ETZPC control through ETZPC_DECPROT0 bit 8) while HASH2 is a non secure peripheral. HASH1 instance can be allocated to: • The Arm® Cortex®-A7 secure core to be controlled in OP-TEE by the HASH OP-TEE driver or • The Arm® Cortex® -A7 non-secure core for using in Linux® with Linux Crypto framework HASH2 instance can be allocated to the Arm® Cortex®-M4 core to be controlled in the STM32Cube MPU Package using the STM32Cube HASH driver. HASH1 instance is used as boot device to support binary authentication. 3 The hash processor supports widely used hash functions including Message Digest 5 (MD5), Secure Hash Algorithm SHA-1 and the more recent SHA-2 with its 224- and 256-bit digest length versions. A hash can also be generated with a secrete-key to produce a message authentication code (MAC). The processor supports bit, byte and half-word swapping. It supports also automatic padding of input data for block alignment. The processor can be used in conjunction with the DMA for automatic processor feeding. -
Downloaded on 2017-02-12T13:16:07Z HARDWARE DESIGNOF CRYPTOGRAPHIC ACCELERATORS
Title Hardware design of cryptographic accelerators Author(s) Baldwin, Brian John Publication date 2013 Original citation Baldwin, B.J., 2013. Hardware design of cryptographic accelerators. PhD Thesis, University College Cork. Type of publication Doctoral thesis Rights © 2013. Brian J. Baldwin http://creativecommons.org/licenses/by-nc-nd/3.0/ Embargo information No embargo required Item downloaded http://hdl.handle.net/10468/1112 from Downloaded on 2017-02-12T13:16:07Z HARDWARE DESIGN OF CRYPTOGRAPHIC ACCELERATORS by BRIAN BALDWIN Thesis submitted for the degree of PHD from the Department of Electrical Engineering National University of Ireland University College, Cork, Ireland May 7, 2013 Supervisor: Dr. William P. Marnane “What I cannot create, I do not understand” - Richard Feynman; on his blackboard at time of death in 1988. Contents 1 Introduction 1 1.1 Motivation...................................... 1 1.2 ThesisAims..................................... 3 1.3 ThesisOutline................................... 6 2 Background 9 2.1 Introduction.................................... 9 2.2 IntroductiontoCryptography. ...... 10 2.3 MathematicalBackground . ... 13 2.3.1 Groups ................................... 13 2.3.2 Rings .................................... 14 2.3.3 Fields.................................... 15 2.3.4 FiniteFields ................................ 16 2.4 EllipticCurves .................................. 17 2.4.1 TheGroupLaw............................... 18 2.4.2 EllipticCurvesoverPrimeFields . .... 19 2.5 CryptographicPrimitives&Protocols -
MD5 Collisions the Effect on Computer Forensics April 2006
Paper MD5 Collisions The Effect on Computer Forensics April 2006 ACCESS DATA , ON YOUR RADAR MD5 Collisions: The Impact on Computer Forensics Hash functions are one of the basic building blocks of modern cryptography. They are used for everything from password verification to digital signatures. A hash function has three fundamental properties: • It must be able to easily convert digital information (i.e. a message) into a fixed length hash value. • It must be computationally impossible to derive any information about the input message from just the hash. • It must be computationally impossible to find two files to have the same hash. A collision is when you find two files to have the same hash. The research published by Wang, Feng, Lai and Yu demonstrated that MD5 fails this third requirement since they were able to generate two different messages that have the same hash. In computer forensics hash functions are important because they provide a means of identifying and classifying electronic evidence. Because hash functions play a critical role in evidence authentication, a judge and jury must be able trust the hash values to uniquely identify electronic evidence. A hash function is unreliable when you can find any two messages that have the same hash. Birthday Paradox The easiest method explaining a hash collision is through what is frequently referred to as the Birthday Paradox. How many people one the street would you have to ask before there is greater than 50% probability that one of those people will share your birthday (same day not the same year)? The answer is 183 (i.e. -
BLAKE2: Simpler, Smaller, Fast As MD5
BLAKE2: simpler, smaller, fast as MD5 Jean-Philippe Aumasson1, Samuel Neves2, Zooko Wilcox-O'Hearn3, and Christian Winnerlein4 1 Kudelski Security, Switzerland [email protected] 2 University of Coimbra, Portugal [email protected] 3 Least Authority Enterprises, USA [email protected] 4 Ludwig Maximilian University of Munich, Germany [email protected] Abstract. We present the hash function BLAKE2, an improved version of the SHA-3 finalist BLAKE optimized for speed in software. Target applications include cloud storage, intrusion detection, or version control systems. BLAKE2 comes in two main flavors: BLAKE2b is optimized for 64-bit platforms, and BLAKE2s for smaller architectures. On 64- bit platforms, BLAKE2 is often faster than MD5, yet provides security similar to that of SHA-3: up to 256-bit collision resistance, immunity to length extension, indifferentiability from a random oracle, etc. We specify parallel versions BLAKE2bp and BLAKE2sp that are up to 4 and 8 times faster, by taking advantage of SIMD and/or multiple cores. BLAKE2 reduces the RAM requirements of BLAKE down to 168 bytes, making it smaller than any of the five SHA-3 finalists, and 32% smaller than BLAKE. Finally, BLAKE2 provides a comprehensive support for tree-hashing as well as keyed hashing (be it in sequential or tree mode). 1 Introduction The SHA-3 Competition succeeded in selecting a hash function that comple- ments SHA-2 and is much faster than SHA-2 in hardware [1]. There is nev- ertheless a demand for fast software hashing for applications such as integrity checking and deduplication in filesystems and cloud storage, host-based intrusion detection, version control systems, or secure boot schemes. -
SPHINCS: Practical Stateless Hash-Based Signatures
SPHINCS: practical stateless hash-based signatures Daniel J. Bernstein1;3, Daira Hopwood2, Andreas Hülsing3, Tanja Lange3, Ruben Niederhagen3, Louiza Papachristodoulou4, Peter Schwabe4, and Zooko Wilcox O'Hearn2 1 Department of Computer Science University of Illinois at Chicago Chicago, IL 606077045, USA [email protected] 2 Least Authority 3450 Emerson Ave. Boulder, CO 803056452 USA [email protected],[email protected] 3 Department of Mathematics and Computer Science Technische Universiteit Eindhoven P.O. Box 513, 5600 MB Eindhoven, The Netherlands [email protected], [email protected], [email protected] 4 Radboud University Nijmegen Digital Security Group P.O. Box 9010, 6500 GL Nijmegen, The Netherlands [email protected], [email protected] Abstract. This paper introduces a high-security post-quantum stateless hash-based sig- nature scheme that signs hundreds of messages per second on a modern 4-core 3.5GHz Intel CPU. Signatures are 41 KB, public keys are 1 KB, and private keys are 1 KB. The signature scheme is designed to provide long-term 2128 security even against attackers equipped with quantum computers. Unlike most hash-based designs, this signature scheme is stateless, allowing it to be a drop-in replacement for current signature schemes. Keywords: post-quantum cryptography, one-time signatures, few-time signatures, hyper- trees, vectorized implementation 1 Introduction It is not at all clear how to securely sign operating-system updates, web-site certicates, etc. once an attacker has constructed a large quantum computer: RSA and ECC are perceived today as being small and fast, but they are broken in polynomial time by Shor's algorithm. -
Recommendation for Applications Using Approved Hash Algorithms
Archived NIST Technical Series Publication The attached publication has been archived (withdrawn), and is provided solely for historical purposes. It may have been superseded by another publication (indicated below). Archived Publication Series/Number: NIST Special Publication 800-107 Title: Recommendation for Applications Using Approved Hash Algorithms Publication Date(s): February 2009 Withdrawal Date: August 2012 Withdrawal Note: SP 800-107 is superseded in its entirety by the publication of SP 800-107 Revision 1 (August 2012). Superseding Publication(s) The attached publication has been superseded by the following publication(s): Series/Number: NIST Special Publication 800-107 Revision 1 Title: Recommendation for Applications Using Approved Hash Algorithms Author(s): Quynh Dang Publication Date(s): August 2012 URL/DOI: http://dx.doi.org/10.6028/NIST.SP.107r1 Additional Information (if applicable) Contact: Computer Security Division (Information Technology Lab) Latest revision of the SP 800-107 Rev. 1 (as of August 12, 2015) attached publication: Related information: http://csrc.nist.gov/ Withdrawal N/A announcement (link): Date updated: ƵŐƵƐƚϭϮ, 2015 NIST Special Publication 800-107 Recommendation for Applications Using Approved Hash Algorithms Quynh Dang Computer Security Division Information Technology Laboratory C O M P U T E R S E C U R I T Y February 2009 U.S. Department of Commerce Otto J. Wolff, Acting Secretary National Institute of Standards and Technology Patrick D. Gallagher, Deputy Director NIST SP 800-107 Abstract Cryptographic hash functions that compute a fixed- length message digest from arbitrary length messages are widely used for many purposes in information security. This document provides security guidelines for achieving the required or desired security strengths when using cryptographic applications that employ the approved cryptographic hash functions specified in Federal Information Processing Standard (FIPS) 180-3. -
Forgery and Key Recovery Attacks for Calico
Forgery and Key Recovery Attacks for Calico Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Martin Schl¨affer Institute for Applied Information Processing and Communications Graz University of Technology Inffeldgasse 16a, A-8010 Graz, Austria April 1, 2014 1 Calico v8 Calico [3] is an authenticated encryption design submitted to the CAESAR competition by Christopher Taylor. In Calico v8 in reference mode, ChaCha-14 and SipHash-2-4 work together in an Encrypt-then-MAC scheme. For this purpose, the key is split into a Cipher Key KC and a MAC Key KM . The plaintext is encrypted with ChaCha under the Cipher Key to a ciphertext with the same length as the plaintext. Then, the tag is calculated as the SipHash MAC of the concatenated ciphertext and associated data. The key used for SipHash is generated by xoring the nonce to the (lower, least significant part of the) MAC Key: (C; T ) = EncCalico(KC k KM ; N; A; P ); where k is concatenation, and with ⊕ denoting xor, the ciphertext and tag are calculated vi C = EncChaCha-14(KC ; N; P ) T = MACSipHash-2-4(KM ⊕ N; C k A): Here, A; P; C denote associated data, plaintext and ciphertext, respectively, all of arbitrary length. T is the 64-bit tag, N the 64-bit nonce, and the 384-bit key K is split into a 256-bit encryption and 128-bit authentication part, K = KC k KM . 2 Missing Domain Separation As shown above, the tag is calculated over the concatenation C k A of ciphertext and asso- ciated data. Due to the missing domain separation between ciphertext and associated data in the generation of the tag, the following attack is feasible. -
Differential Cryptanalysis of Siphash
Differential Cryptanalysis of SipHash Christoph Dobraunig, Florian Mendel, and Martin Schl¨affer IAIK, Graz University of Technology, Austria [email protected] Abstract. SipHash is an ARX based message authentication code de- veloped by Aumasson and Bernstein. SipHash was designed to be fast on short messages. Already, a lot of implementations and applications for SipHash exist, whereas the cryptanalysis of SipHash lacks behind. In this paper, we provide the first published third-party cryptanalysis of SipHash regarding differential cryptanalysis. We use existing auto- matic tools to find differential characteristics for SipHash. To improve the quality of the results, we propose several extensions for these tools to find differential characteristics. For instance, to get a good probabil- ity estimation for differential characteristics in SipHash, we generalize the concepts presented by Mouha et al. and Velichkov et al. to calcu- late the probability of ARX functions. Our results are a characteristic for SipHash-2-4 with a probability of 2−236:3 and a distinguisher for the Finalization of SipHash-2-4 with practical complexity. Even though our results do not pose any threat to the security of SipHash-2-4, they sig- nificantly improve the results of the designers and give new insights in the security of SipHash-2-4. Keywords: message authentication code, MAC, cryptanalysis, differ- ential cryptanalysis, SipHash, S-functions, cyclic S-functions 1 Introduction A message authentication code (MAC) is a cryptographic primitive, which is used to ensure the integrity and the origin of messages. Normally, a MAC takes a secret key K and a message M as input and produces a fixed size tag T .A receiver of such a message-tag-pair verifies the authenticity of the message by simply recalculating the tag T for the message and compare it with the received one. -
Lightweight Macs from Universal Hash Functions
Lightweight MACs from Universal Hash Functions S´ebastienDuval Ga¨etanLeurent November 13, 2019 REASSURE Introduction Design of MAC611 Benchmarks Conclusion 2 / 21 Authentication I Need for lightweight crypto I Relatively few authentication solutions compared to encryption I Our goal: design a fast MAC, MAC611, for 32-bit micro-controllers Introduction Design of MAC611 Benchmarks Conclusion 3 / 21 MACs Message Authentication Code I Definition: Tag t = Hk (m) I Security: bound on the proba. that an adversary forges a valid tag MAC constructions: I Block-Cipher-based (CBC-MAC, PMAC) I Hash-Function-based (HMAC) I from scratch (Pelican MAC, Chaskey) I from Universal Hash Functions (GMAC, Poly1305-AES) Lightweight MACs Chaskey, SipHash, TuLP, LightMAC, QUARK, SPONGENT Aim for 64-bit security Introduction Design of MAC611 Benchmarks Conclusion 3 / 21 MACs Message Authentication Code I Definition: Tag t = Hk (m) I Security: bound on the proba. that an adversary forges a valid tag MAC constructions: I Block-Cipher-based (CBC-MAC, PMAC) I Hash-Function-based (HMAC) I from scratch (Pelican MAC, Chaskey) I from Universal Hash Functions (GMAC, Poly1305-AES) Lightweight MACs Chaskey, SipHash, TuLP, LightMAC, QUARK, SPONGENT Aim for 64-bit security Introduction Design of MAC611 Benchmarks Conclusion 4 / 21 [Almost] Universal Hash Functions A family H : A B is: ! "-almost universal ("-AU) m = m0 A; h H : h(m) = h(m0) " H 8 6 2 jf 2 gj ≤ j j "-almost XOR universal ("-AXU) m = m0 A; d B; h H : h(m) h(m0) = d " H 8 6 2 8 2 jf 2 ⊕ gj ≤ j j H "-AXU H "-AU, -
Hash Pile Ups: Using Collisions to Identify Unknown Hash Functions
Hash Pile Ups: Using Collisions to Identify Unknown Hash Functions R. Joshua Tobin David Malone School of Mathematics Hamilton Institute Trinity College Dublin, National University of Ireland, Ireland. Ireland. Email: [email protected] Email: [email protected] Abstract—Hash functions are often used to consistently assign 16 Xor Jenkins objects to particular resources, for example to load balancing Pearson in networks. These functions can be randomly selected from a 14 Universal MD5 family, to prevent attackers generating many colliding objects, SHA which usually results in poor performance. We describe a number 12 SHA256 of attacks allowing us to identify which hash function from a family is being used by observing a relatively small number of 10 collisions. This knowledge can then be used to generate a large number of colliding inputs. In particular we detail attacks against (us) 8 CPU Time small families of hashes, Pearson-like hash functions and linear 6 hashes, such as the Toeplitz hash used in Microsoft’s Receive Side Scaling. 4 I. INTRODUCTION 2 Hash functions are often used to spread load across several 0 resources. For example, in the common case of a hash table, a Geode Core 2 Duo Athlon 64 Xeon Atom 500MHz 2.66GHz 2.6GHz 3GHz 1.6GHz hash function is used to give a consistent assignment of objects to linked lists. In modern networking, similar techniques are used by high-end network cards to assign packets to CPUs [1], Fig. 1. The average cost of hashing an IPv6 flow record with different algorithms on a selection of CPUs. -
Fast Collision Attack on MD5
Fast Collision Attack on MD5 Marc Stevens Department of Mathematics and Computer Science, Eindhoven University of Technology P.O. Box 513, 5600 MB Eindhoven, The Netherlands. [email protected] Abstract. In this paper, we present an improved attack algorithm to find two-block colli- sions of the hash function MD5. The attack uses the same differential path of MD5 and the set of sufficient conditions that was presented by Wang et al. We present a new technique which allows us to deterministically fulfill restrictions to properly rotate the differentials in the first round. We will present a new algorithm to find the first block and we will use an al- gorithm of Klima to find the second block. To optimize the inner loop of these algorithms we will optimize the set of sufficient conditions. We also show that the initial value used for the attack has a large influence on the attack complexity. Therefore a recommendation is made for 2 conditions on the initial value of the attack to avoid very hard situations if one has some freedom in choosing this initial value. Our attack can be done in an average of about 1 minute (avg. complexity 232.3) on a 3Ghz Pentium4 for these random recommended initial values. For arbitrary random initial values the average is about 5 minutes (avg. complexity 234.1). With a reasonable probability a collision is found within mere seconds, allowing for instance an attack during the execution of a protocol. Keywords: MD5, collision, differential cryptanalysis 1 Introduction Hash functions are among the primitive functions used in cryptography, because of their one- way and collision free properties.