How to Break MD5 and Other Hash Functions
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FIPS 140-2 Non-Proprietary Security Policy
Kernel Crypto API Cryptographic Module version 1.0 FIPS 140-2 Non-Proprietary Security Policy Version 1.3 Last update: 2020-03-02 Prepared by: atsec information security corporation 9130 Jollyville Road, Suite 260 Austin, TX 78759 www.atsec.com © 2020 Canonical Ltd. / atsec information security This document can be reproduced and distributed only whole and intact, including this copyright notice. Kernel Crypto API Cryptographic Module FIPS 140-2 Non-Proprietary Security Policy Table of Contents 1. Cryptographic Module Specification ..................................................................................................... 5 1.1. Module Overview ..................................................................................................................................... 5 1.2. Modes of Operation ................................................................................................................................. 9 2. Cryptographic Module Ports and Interfaces ........................................................................................ 10 3. Roles, Services and Authentication ..................................................................................................... 11 3.1. Roles .......................................................................................................................................................11 3.2. Services ...................................................................................................................................................11 -
Increasing Cryptography Security Using Hash-Based Message
ISSN (Print) : 2319-8613 ISSN (Online) : 0975-4024 Seyyed Mehdi Mousavi et al. / International Journal of Engineering and Technology (IJET) Increasing Cryptography Security using Hash-based Message Authentication Code Seyyed Mehdi Mousavi*1, Dr.Mohammad Hossein Shakour 2 1-Department of Computer Engineering, Shiraz Branch, Islamic AzadUniversity, Shiraz, Iran . Email : [email protected] 2-Assistant Professor, Department of Computer Engineering, Shiraz Branch, Islamic Azad University ,Shiraz ,Iran Abstract Nowadays, with the fast growth of information and communication technologies (ICTs) and the vulnerabilities threatening human societies, protecting and maintaining information is critical, and much attention should be paid to it. In the cryptography using hash-based message authentication code (HMAC), one can ensure the authenticity of a message. Using a cryptography key and a hash function, HMAC creates the message authentication code and adds it to the end of the message supposed to be sent to the recipient. If the recipient of the message code is the same as message authentication code, the packet will be confirmed. The study introduced a complementary function called X-HMAC by examining HMAC structure. This function uses two cryptography keys derived from the dedicated cryptography key of each packet and the dedicated cryptography key of each packet derived from the main X-HMAC cryptography key. In two phases, it hashes message bits and HMAC using bit Swapp and rotation to left. The results show that X-HMAC function can be a strong barrier against data identification and HMAC against the attacker, so that it cannot attack it easily by identifying the blocks and using HMAC weakness. -
CHAPTER 9: ANALYSIS of the SHA and SHA-L HASH ALGORITHMS
CHAPTER 9: ANALYSIS OF THE SHA AND SHA-l HASH ALGORITHMS In this chapter the SHA and SHA-l hash functions are analysed. First the SHA and SHA-l hash functions are described along with the relevant notation used in this chapter. This is followed by describing the algebraic structure of the message expansion algorithm used by SHA. We then proceed to exploit this algebraic structure of the message expansion algorithm by applying the generalised analysis framework presented in Chapter 8. We show that it is possible to construct collisions for each of the individual rounds of the SHA hash function. The source code that implements the attack is attached in Appendix F. The same techniques are then applied to SHA-l. SHA is an acronym for Secure Hash Algorithm. SHA and SHA-l are dedicated hash func- tions based on the iterative Damgard-Merkle construction [22] [23]. Both of the round func- tions utilised by these algorithms take a 512 bit input (or a multiple of 512) and produce a 160 bit hash value. SHA was first published as Federal Information Processing Standard 180 (FIPS 180). The secure hash algorithm is based on principles similar to those used in the design of MD4 [10]. SHA-l is a technical revision of SHA and was published as FIPS 180-1 [13]. It is believed that this revision makes SHA-l more secure than SHA [13] [50] [59]. SHA and SHA-l differ from MD4 with regard to the number of rounds used, the size of the hash result and the definition of a single step. -
Fast Hashing and Stream Encryption with Panama
Fast Hashing and Stream Encryption with Panama Joan Daemen1 and Craig Clapp2 1 Banksys, Haachtesteenweg 1442, B-1130 Brussel, Belgium [email protected] 2 PictureTel Corporation, 100 Minuteman Rd., Andover, MA 01810, USA [email protected] Abstract. We present a cryptographic module that can be used both as a cryptographic hash function and as a stream cipher. High performance is achieved through a combination of low work-factor and a high degree of parallelism. Throughputs of 5.1 bits/cycle for the hashing mode and 4.7 bits/cycle for the stream cipher mode are demonstrated on a com- mercially available VLIW micro-processor. 1 Introduction Panama is a cryptographic module that can be used both as a cryptographic hash function and a stream cipher. It is designed to be very efficient in software implementations on 32-bit architectures. Its basic operations are on 32-bit words. The hashing state is updated by a parallel nonlinear transformation, the buffer operates as a linear feedback shift register, similar to that applied in the compression function of SHA [6]. Panama is largely based on the StepRightUp stream/hash module that was described in [4]. Panama has a low per-byte work factor while still claiming very high security. The price paid for this is a relatively high fixed computational overhead for every execution of the hash function. This makes the Panama hash function less suited for the hashing of messages shorter than the equivalent of a typewritten page. For the stream cipher it results in a relatively long initialization procedure. Hence, in applications where speed is critical, too frequent resynchronization should be avoided. -
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. -
A Full Key Recovery Attack on HMAC-AURORA-512
A Full Key Recovery Attack on HMAC-AURORA-512 Yu Sasaki NTT Information Sharing Platform Laboratories, NTT Corporation 3-9-11 Midori-cho, Musashino-shi, Tokyo, 180-8585 Japan [email protected] Abstract. In this note, we present a full key recovery attack on HMAC- AURORA-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 com- plexity is 2259 AURORA-512 operations, which is significantly less than the complexity of the exhaustive search for a 512-bit key. The attack can be carried out with a negligible amount of memory. Our attack can also recover the inner-key of HMAC-AURORA-384 with almost the same complexity as in HMAC-AURORA-512. This attack does not recover the outer-key of HMAC-AURORA-384, but universal forgery is possible by combining the inner-key recovery and 2nd-preimage attacks. Our attack exploits some weaknesses in the mode of operation. keywords: AURORA, DMMD, HMAC, Key recovery attack 1 Description 1.1 Mode of operation for AURORA-512 We briefly describe the specification of AURORA-512. Please refer to Ref. [2] for details. An input message is padded to be a multiple of 512 bits by the standard MD message padding, then, the padded message is divided into 512-bit message blocks (M0;M1;:::;MN¡1). 256 512 256 In AURORA-512, compression functions Fk : f0; 1g £f0; 1g ! f0; 1g 256 512 256 512 and Gk : f0; 1g £ f0; 1g ! f0; 1g , two functions MF : f0; 1g ! f0; 1g512 and MFF : f0; 1g512 ! f0; 1g512, and two initial 256-bit chaining U D 1 values H0 and H0 are defined . -
The First Collision for Full SHA-1
The first collision for full SHA-1 Marc Stevens1, Elie Bursztein2, Pierre Karpman1, Ange Albertini2, Yarik Markov2 1 CWI Amsterdam 2 Google Research [email protected] https://shattered.io Abstract. SHA-1 is a widely used 1995 NIST cryptographic hash function standard that was officially deprecated by NIST in 2011 due to fundamental security weaknesses demonstrated in various analyses and theoretical attacks. Despite its deprecation, SHA-1 remains widely used in 2017 for document and TLS certificate signatures, and also in many software such as the GIT versioning system for integrity and backup purposes. A key reason behind the reluctance of many industry players to replace SHA-1 with a safer alternative is the fact that finding an actual collision has seemed to be impractical for the past eleven years due to the high complexity and computational cost of the attack. In this paper, we demonstrate that SHA-1 collision attacks have finally become practical by providing the first known instance of a collision. Furthermore, the prefix of the colliding messages was carefully chosen so that they allow an attacker to forge two PDF documents with the same SHA-1 hash yet that display arbitrarily-chosen distinct visual contents. We were able to find this collision by combining many special cryptanalytic techniques in complex ways and improving upon previous work. In total the computational effort spent is equivalent to 263:1 SHA-1 compressions and took approximately 6 500 CPU years and 100 GPU years. As a result while the computational power spent on this collision is larger than other public cryptanalytic computations, it is still more than 100 000 times faster than a brute force search. -
Related-Key and Key-Collision Attacks Against RMAC
Related-Key and Key-Collision Attacks Against RMAC Tadayoshi Kohno CSE Department, UC San Diego 9500 Gilman Drive, MC-0114 La Jolla, California 92093-0114, USA IACR ePrint archive 2002/159, 21 October 2002, revised 2 December 2002. Abstract. In [JJV02] Jaulmes, Joux, and Valette propose a new ran- domized message authentication scheme, called RMAC, which NIST is currently in the process of standardizing [NIS02]. In this work we present several attacks against RMAC. The attacks are based on a new protocol- level related-key attack against RMAC and can be considered variants of Biham’s key-collision attack [Bih02]. These attacks provide insights into the RMAC design. We believe that the protocol-level related-key attack is of independent interest. Keywords: RMAC, key-collision attacks, related-key attacks. 1 Introduction Jaulmes, Joux, and Valette’s RMAC construction [JJV02] is a new ran- domized message authentication scheme. Similar to Petrank and Rackoff’s DMAC construction [PR97] and Black and Rogaway’s ECBC construc- tion [BR00], the RMAC construction is a CBC-MAC variant in which an input message is first MACed with standard CBC-MAC and then the resulting intermediate value is enciphered with one additional block ci- pher application. Rather than using a fixed key for the last block cipher application (as DMAC and ECBC do), RMAC enciphers the last block with a randomly chosen (but related) key. One immediate observation is that RMAC directly exposes the underlying block cipher to a weak form of related-key attacks [Bih93]. We are interested in attacks that do not exploit some related-key weakness of the underlying block cipher, but rather some property of the RMAC mode itself. -
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. -
A New Approach in Expanding the Hash Size of MD5
374 International Journal of Communication Networks and Information Security (IJCNIS) Vol. 10, No. 2, August 2018 A New Approach in Expanding the Hash Size of MD5 Esmael V. Maliberan, Ariel M. Sison, Ruji P. Medina Graduate Programs, Technological Institute of the Philippines, Quezon City, Philippines Abstract: The enhanced MD5 algorithm has been developed by variants and RIPEMD-160. These hash algorithms are used expanding its hash value up to 1280 bits from the original size of widely in cryptographic protocols and internet 128 bit using XOR and AND operators. Findings revealed that the communication in general. Among several hashing hash value of the modified algorithm was not cracked or hacked algorithms mentioned above, MD5 still surpasses the other during the experiment and testing using powerful bruteforce, since it is still widely used in the domain authentication dictionary, cracking tools and rainbow table such as security owing to its feature of irreversible [41]. This only CrackingStation, Hash Cracker, Cain and Abel and Rainbow Crack which are available online thus improved its security level means that the confirmation does not need to demand the compared to the original MD5. Furthermore, the proposed method original data but only need to have an effective digest to could output a hash value with 1280 bits with only 10.9 ms confirm the identity of the client. The MD5 message digest additional execution time from MD5. algorithm was developed by Ronald Rivest sometime in 1991 to change a previous hash function MD4, and it is commonly Keywords: MD5 algorithm, hashing, client-server used in securing data in various applications [27,23,22]. -
Cryptanalysis of MD4
Cryptanalysis of MD4 Hans Dobbertin German Information Security Agency P. O. Box 20 03 63 D-53133 Bonn e-maih dobbert inQskom, rhein .de Abstract. In 1990 Rivest introduced the hash function MD4. Two years later RIPEMD, a European proposal, was designed as a stronger mode of MD4. Recently wc have found an attack against two of three rounds of RIPEMD. As we shall show in the present note, the methods developed to attack RIPEMD can be modified and supplemented such that it is possible to break the full MD4, while previously only partial attacks were known. An implementation of our attack allows to find collisions for MD4 in a few seconds on a PC. An example of a collision is given demonstrating that our attack is of practical relevance. 1 Introduction Rivest [7] introduced the hash function MD4 in 1990. The MD4 algorithm is defined as an iterative application of a three-round compress function. After an unpublished attack on the first two rounds of MD4 due to Merkle and an attack against the last two rounds by den Boer and Bosselaers [2], Rivest introduced the strengthened version MD5 [8]. The most important difference to MD4 is the adding of a fourth round. On the other hand the stronger mode RIPEMD [1] of MD4 was designed as a European proposal in 1992. The compress function of RIPEMD consists of two parallel lines of a modified version of the MD4 compress function. In [4] we have shown that if the first or the last round of its compress function is omitted, then RIPEMD is not collision-free. -
Efficient Collision Attack Frameworks for RIPEMD-160
Efficient Collision Attack Frameworks for RIPEMD-160 Fukang Liu1;6, Christoph Dobraunig2;3, Florian Mendel4, Takanori Isobe5;6, Gaoli Wang1?, and Zhenfu Cao1? 1 Shanghai Key Laboratory of Trustworthy Computing, East China Normal University, Shanghai, China [email protected],fglwang,[email protected] 2 Graz University of Technology, Austria 3 Radboud University, Nijmegen, The Netherlands [email protected] 4 Infineon Technologies AG, Germany [email protected] 5 National Institute of Information and Communications Technology, Japan 6 University of Hyogo, Japan [email protected] Abstract. RIPEMD-160 is an ISO/IEC standard and has been applied to gen- erate the Bitcoin address with SHA-256. Due to the complex dual-stream struc- ture, the first collision attack on reduced RIPEMD-160 presented by Liu, Mendel and Wang at Asiacrypt 2017 only reaches 30 steps, having a time complexity of 270. Apart from that, several semi-free-start collision attacks have been published for reduced RIPEMD-160 with the start-from-the-middle method. Inspired from such start-from-the middle structures, we propose two novel efficient collision at- tack frameworks for reduced RIPEMD-160 by making full use of the weakness of its message expansion. Those two frameworks are called dense-left-and-sparse- right (DLSR) framework and sparse-left-and-dense-right (SLDR) framework. As it turns out, the DLSR framework is more efficient than SLDR framework since one more step can be fully controlled, though with extra 232 memory complexi- ty. To construct the best differential characteristics for the DLSR framework, we carefully build the linearized part of the characteristics and then solve the cor- responding nonlinear part using a guess-and-determine approach.