Browse free open source C Algorithms and projects below. Use the toggles on the left to filter open source C Algorithms by OS, license, language, programming language, and project status.

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  • 1
    RHash
    RHash (Recursive Hasher) is a console utility for computing and verifying hash sums of files. It supports CRC32, CRC32C, MD4, MD5, SHA1, SHA256, SHA512, SHA3, AICH, ED2K, DC++ TTH, BTIH, Tiger, GOST R 34.11-2012, RIPEMD-160, HAS-160, EDON-R, and Whirlpool.
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    Downloads: 916 This Week
    Last Update:
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  • 2
    ArpON

    ArpON

    ARP handler inspection

    ArpON (ARP handler inspection) is a Host-based solution that make the ARP standardized protocol secure in order to avoid the Man In The Middle (MITM) attack through the ARP spoofing, ARP cache poisoning or ARP poison routing attack.
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    Downloads: 58 This Week
    Last Update:
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  • 3
    xxHash

    xxHash

    Extremely fast non-cryptographic hash algorithm

    xxHash is an extremely fast non-cryptographic hash algorithm, working at RAM speed limit. It is proposed in four flavors (XXH32, XXH64, XXH3_64bits and XXH3_128bits). The latest variant, XXH3, offers improved performance across the board, especially on small data. It successfully completes the SMHasher test suite which evaluates collision, dispersion and randomness qualities of hash functions. Code is highly portable, and hashes are identical across all platforms (little / big endian). Performance on large data is only one part of the picture. Hashing is also very useful in constructions like hash tables and bloom filters. In these use cases, it's frequent to hash a lot of small data (starting at a few bytes). Algorithm's performance can be very different for such scenarios, since parts of the algorithm, such as initialization or finalization, become fixed cost. The impact of branch misprediction also becomes much more present.
    Downloads: 3 This Week
    Last Update:
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  • 4
    The Safe C Library provides bound checking memory and string functions per ISO/IEC TR24731. These functions are alternative functions to the existing standard C library that promote safer, more secure programming. The ISO/IEC Programming languages — C spec, C11, now includes the bounded APIs in Appendix K, "Bounds-checking interfaces". This latest upload supports building static library, a shared library and a linux kernel module.
    Downloads: 17 This Week
    Last Update:
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  • 5
    A package of Rijndael, Twofish and Serpent encryption algorithms implemented in x86 assembly. Meant to learn basics of assembly, learn about the algorithms or to be used in a C program.
    Downloads: 0 This Week
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  • 6
    Portable, optimised implementation of Bruce Schneier's 64-bit symmetric block cipher, Blowfish. Includes support for ECB, CBC, CFB, OFB and CTR block cipher modes, weak key detection and parallelisation using OpenMP.
    Downloads: 0 This Week
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  • 7

    Cryptography Tools

    Classic & Modern Cryptography tools

    Cryptography Tools is a project to develop demonstration tools on classic (currently Caesar and Playfair) & modern crypto-systems, including private & public key encryptions, digital signatures, cryptographic hashes and authenticated encryption.
    Downloads: 0 This Week
    Last Update:
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  • 8
    The IEEE 1619 Committee open-source reference implementations of encryption algorithms, plus testing and certification suites, for each encryption algorithm included in the standard.
    Downloads: 0 This Week
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  • 9
    The PowerCiph Data Encryption Algorithm is a versatile, yet simplistic, encryption algorithm/protocol. The ultimate goal of the algorithm is simplicity, compactness, and a lack of prerequisites.
    Downloads: 0 This Week
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  • 10

    Primes

    Calculate primes by using extremely fast sorting

    This project considers the problem of calculating primes as a sorting problem. It includes the most efficient tree-based sorting algorithm that is possible and shows that finding a new prime can be done by sorting the differences between the previous primes in the right way. Unfortunately it has turned out that going this way is even more slowly than trying to find primes by brute force. So it can only be used as a test with heavy load for the sorting algorithm, which can be used for sorting any kind of data. And as already mentioned, it's just the most efficient tree-based sorting algorithm that you can get. But furthermore this way of finding primes interestingly leaves a hard nut to crack for mathematicians: In very rare cases it finds numbers that are not primes. For all primes below one million this phenomenon arises in exactly two cases: 31213 which is 7 * 7 * 7 * 7 * 13 336141 which is 3 * 3 * 13 * 13 * 13 * 17 Who can explain, why?
    Downloads: 0 This Week
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  • 11
    Raiden block cipher: An extremely lightweight and fast block cipher, developed using genetic programming, with the intention to be an alternative to TEA. This cipher is as fast as TEA, and without many of its known weaknesses.
    Downloads: 0 This Week
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  • 12
    A GLib/GTK+ classical encryption analysis and reversal tool that brings together multiple techniques into a single program to aide in decryption.
    Downloads: 0 This Week
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  • 13
    Fast cryptography extension for Tcl. TclTomCrypt is a sensible binding that brings the features and performance of LibTomCrypt to Tcl.
    Downloads: 0 This Week
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  • 14
    Three software packages to work with RFC2617 digests: libdigest (C library to compute digests), libcppdigest (C++ library to manage /etc/passwd-like files) and libpam-digestfile (PAM module allowing authentication via an /etc/passwd-like file)
    Downloads: 0 This Week
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  • 15
    WORDFIELD is an extremely fast incremental word list generator. It's meant for use with a password recovery tool such as John the Ripper or aircrack-ng.
    Downloads: 0 This Week
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  • 16
    Wireless DCC, Digital Command Control for model railroad over 802.15.4 the network nodes being the handhelds and the DCC decoders themself. Backward compatibility with DCC will be kept but new users wont need command stations and boosters.
    Downloads: 0 This Week
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  • 17
    leet

    leet

    Leet is CCEx's software application for on-the-fly encryption (OTFE).

    The name leet stands for "Linux exquisite encryption tool", it will be a software application for on-the-fly encryption, similar in its functionality to TrueCrypt. The goal of leet however is to be simpler and as user friendly as possible, making encryption and securing of information accessible to anybody, even those who don't necessarily have any prior knowledge of data securing, algorithms and encryption. However it's not targeted at this group of users only, part of the ambition of this project is to reach companies, institutions, governments (etc...) as well.
    Downloads: 0 This Week
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  • 18
    libObfuscate
    libObfuscate 2.00 ISO C / open-source / system independent * Modern 256bit cryptography: AES, Anubis, Camellia, Cast-256, Clefia, FROG, Hierocrypt3, Idea-NXT, MARS, RC6, Safer+, SC2000, Serpent, Speed, Twofish, Unicorn-A, Wrapper * CSPRNG (based on AES) * Modern 512bit hashing: Grostl, Keccak, SHA2, Skein, Wrapper * Scrambling * Multi-layered obfuscation
    Downloads: 0 This Week
    Last Update:
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