|
Mcrypt
mcrypt is a replacement for the popular Unix crypt command. crypt was a file encryption tool that used an algorithm very close to the World War II Enigma cipher. Mcrypt provides the same functionality but uses several modern algorithms such as AES. Libmcrypt, Mcrypt's companion, is a library of code that contains the actual encryption functions and provides an easy method for use. The last update to libmcrypt was in 2007, despite years of unmerged patches. Maintained alternatives include ccrypt, libressl, and others. Examples of mcrypt usage in a Linux command-line environment: mcrypt --list # See available encryption algorithms. mcrypt -a blowfish myfilename # Encrypts myfilename to myfilename.nc # using the Blowfish encryption algorithm. # You are prompted two times for a passphrase. mcrypt -d mytextfile.txt.nc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems ( SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM ( AIX). The early versions of Unix—which are retrospectively referred to as " Research Unix"—ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards. It distinguished itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language (in 1973), which allows U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Encryption Standard
The Data Encryption Standard (DES ) is a symmetric-key algorithm for the encryption of digital data. Although its short key length of 56 bits makes it too insecure for modern applications, it has been highly influential in the advancement of cryptography. Developed in the early 1970s at IBM and based on an earlier design by Horst Feistel, the algorithm was submitted to the National Bureau of Standards (NBS) following the agency's invitation to propose a candidate for the protection of sensitive, unclassified electronic government data. In 1976, after consultation with the National Security Agency (NSA), the NBS selected a slightly modified version (strengthened against differential cryptanalysis, but weakened against brute-force attacks), which was published as an official Federal Information Processing Standard (FIPS) for the United States in 1977. The publication of an NSA-approved encryption standard led to its quick international adoption and widespread academic scrutiny. C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crypt (Unix)
In Unix computing, crypt or enigma is a utility program used for encryption. Due to the ease of breaking it, it is considered to be obsolete. The program is usually used as a filter, and it has traditionally been implemented using a "rotor machine" algorithm based on the Enigma machine. It is considered to be cryptographically far too weak to provide any security against brute-force attacks by modern, commodity personal computers. Some versions of Unix shipped with an even weaker version of the ''crypt(1)'' command in order to comply with contemporaneous laws and regulations that limited the exportation of cryptographic software. Some of these were simply implementations of the Caesar cipher (effectively no more secure than ROT13, which is implemented as a Caesar cipher with a well-known key). History Cryptographer Robert Morris wrote a M-209-based , which first appeared in Version 3 Unix, to encourage codebreaking experiments; Morris managed to break by hand. Dennis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bcrypt
bcrypt is a password-hashing function designed by Niels Provos and David Mazières. It is based on the Blowfish (cipher), Blowfish cipher and presented at USENIX in 1999. Besides incorporating a salt (cryptography), salt to protect against rainbow table attacks, bcrypt is an adaptive function: over time, the iteration count can be increased to make it slower, so it remains resistant to brute-force search attacks even with increasing computation power. The bcrypt function is the default password hash algorithm for OpenBSD, and was the default for some Linux distributions such as SUSE Linux. There are implementations of bcrypt in C (programming language), C, C++, C Sharp (programming language), C#, Embarcadero Delphi, Elixir (programming language), Elixir, Go (programming language), Go, Java (programming language), Java, JavaScript, Perl, PHP, Ruby (programming language), Ruby, Python (programming language), Python, Rust (programming language), Rust,V (programming language), V ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XTEA
In cryptography, XTEA (eXtended TEA) is a block cipher designed to correct weaknesses in TEA. The cipher's designers were David Wheeler and Roger Needham of the Cambridge Computer Laboratory, and the algorithm was presented in an unpublished technical report in 1997 (Needham and Wheeler, 1997). It is not subject to any patents. Like TEA, XTEA is a 64-bit block Feistel cipher with a 128-bit key and a suggested 64 rounds. Several differences from TEA are apparent, including a somewhat more complex key-schedule and a rearrangement of the shifts, XORs, and additions. Implementations This standard C source code, adapted from the reference code released into the public domain by David Wheeler and Roger Needham, encrypts and decrypts using XTEA: #include /* take 64 bits of data in v and v and 128 bits of key - key */ void encipher(unsigned int num_rounds, uint32_t v uint32_t const key void decipher(unsigned int num_rounds, uint32_t v uint32_t const key The changes fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WAKE (cipher)
In cryptography, WAKE is a stream cipher designed by David Wheeler in 1993. WAKE stands for Word Auto Key Encryption. The cipher works in ''cipher feedback'' mode, generating keystream blocks from previous ciphertext blocks. WAKE uses an S-box with 256 entries of 32-bit words. The cipher is fast, but vulnerable to chosen plaintext and chosen ciphertext attacks.Bruce Schneier, ''Applied Cryptography'', Second Edition, page 402. Characteristics and vulnerability WAKE is noted for its speed, making it suitable for applications requiring fast encryption. However, it has been found to be vulnerable to both chosen plaintext and chosen ciphertext attacks. These vulnerabilities arise from the cipher's reliance on previous ciphertext blocks for keystream generation, which can be exploited in certain attack scenarios. Research has indicated that WAKE's design allows for effective chosen plaintext attacks, where an attacker can choose arbitrary plaintexts to be encrypted and analyze the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twofish
In cryptography, Twofish is a symmetric key block cipher with a block size of 128 bits and key sizes up to 256 bits. It was one of the five finalists of the Advanced Encryption Standard contest, but it was not selected for standardization. Twofish is related to the earlier block cipher Blowfish. Twofish's distinctive features are the use of pre-computed key-dependent S-boxes, and a relatively complex key schedule. One half of an n-bit key is used as the actual encryption key and the other half of the n-bit key is used to modify the encryption algorithm (key-dependent S-boxes). Twofish borrows some elements from other designs; for example, the pseudo-Hadamard transform (PHT) from the SAFER family of ciphers. Twofish has a Feistel structure like DES. Twofish also employs a Maximum Distance Separable matrix. When it was introduced in 1998, Twofish was slightly slower than Rijndael (the chosen algorithm for Advanced Encryption Standard) for 128-bit keys, but somewhat faster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serpent (cipher)
Serpent is a symmetric key block cipher that was a finalist in the Advanced Encryption Standard process, Advanced Encryption Standard (AES) contest, in which it ranked second to Rijndael. Serpent was designed by Ross J. Anderson, Ross Anderson, Eli Biham, and Lars Knudsen. Like other Advanced Encryption Standard, AES submissions, Serpent has a block size (cryptography), block size of 128 bits and supports a key size of 128, 192, or 256 bits. The cipher is a 32-round substitution–permutation network operating on a block of four 32-bit Word (computer architecture), words. Each round applies one of eight 4-bit to 4-bit S-boxes 32 times in parallel. Serpent was designed so that all operations can be executed in parallel computing, parallel, using 32 bit slices. This maximizes parallelism but also allows use of the extensive cryptanalysis work performed on Data Encryption Standard, DES. Serpent took a conservative approach to security, opting for a large security margin: the design ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LOKI97
In cryptography, LOKI97 is a block cipher which was a candidate in the Advanced Encryption Standard competition. It is a member of the LOKI family of ciphers, with earlier instances being LOKI89 and LOKI91. LOKI97 was designed by Lawrie Brown, assisted by Jennifer Seberry and Josef Pieprzyk. Like DES, LOKI97 is a 16-round Feistel cipher, and like other AES candidates, has a 128-bit block size and a choice of a 128-, 192- or 256-bit key length. It uses 16 rounds of a balanced Feistel network to process the input data blocks (see diagram right). The complex round function f incorporates two substitution-permutation layers in each round. The key schedule is also a Feistel structure – an unbalanced one unlike the main network — but using the same F-function. The LOKI97 round function (shown right) uses two columns each with multiple copies of two basic S-boxes. These S-boxes are designed to be highly non-linear and have a good XOR profile. The permutations before and betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GOST (block Cipher)
The GOST block cipher (Magma), defined in the standard GOST 28147-89 (RFC 5830), is a Soviet and Russian government standard symmetric key block cipher with a block size of 64 bits. The original standard, published in 1989, did not give the cipher any name, but the most recent revision of the standard, GOST R 34.12-2015 (RFC 7801, RFC 8891), specifies that it may be referred to as Magma. The GOST hash function is based on this cipher. The new standard also specifies a new 128-bit block cipher called Kuznyechik. Developed in the 1970s, the standard had been marked "Top Secret" and then downgraded to "Secret" in 1990. Shortly after the dissolution of the USSR, it was declassified and it was released to the public in 1994. GOST 28147 was a Soviet alternative to the United States standard algorithm, DES. Thus, the two are very similar in structure. The algorithm GOST has a 64-bit block size and a key length of 256 bits. Its S-boxes can be secret, and they contain about 354 (lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blowfish (cipher)
Blowfish is a Symmetric-key algorithm, symmetric-key block cipher, designed in 1993 by Bruce Schneier and included in many cipher suites and encryption products. Blowfish provides a good encryption rate in software, and no effective cryptanalysis of it has been found to date for smaller files. It is recommended Blowfish should not be used to encrypt files larger than 4GB in size, Twofish should be used instead. Blowfish has a 64-bit block size and therefore it could be vulnerable to Sweet32 birthday attacks. Schneier designed Blowfish as a general-purpose algorithm, intended as an alternative to the aging Data Encryption Standard, DES and free of the problems and constraints associated with other algorithms. At the time Blowfish was released, many other designs were proprietary, encumbered by patents, or were commercial or government secrets. Schneier has stated that "Blowfish is unpatented, and will remain so in all countries. The algorithm is hereby placed in the public domai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
