NaCl (pronounced "salt") is an abbreviation for "Networking and Cryptography library", a

public domain The public domain (PD) consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable. Because those rights have expired, ...

"...high-speed software library for network communication, encryption, decryption, signatures, etc". NaCl was created by the mathematician and programmer

Daniel J. Bernstein Daniel Julius Bernstein (sometimes known as djb; born October 29, 1971) is an American German mathematician, cryptologist, and computer scientist. He is a visiting professor at CASA at Ruhr University Bochum, as well as a research professor of ...

who is best known for the creation of

qmail qmail is a mail transfer agent (MTA) that runs on Unix. It was written, starting December 1995, by Daniel J. Bernstein as a more secure replacement for the popular Sendmail program. Originally license-free software, qmail's source code ...

and

Curve25519 In cryptography, Curve25519 is an elliptic curve used in elliptic-curve cryptography (ECC) offering 128 bits of security (256-bit key size) and designed for use with the elliptic curve Diffie–Hellman (ECDH) key agreement scheme. It is one ...

. The core team also includes Tanja Lange and Peter Schwabe. The main goal while creating NaCl, according to the paper, was to "avoid various types of cryptographic disasters suffered by previous cryptographic libraries".https://cr.yp.to/highspeed/coolnacl-20120725.pdf "The security impact of a new cryptographic library" Daniel J. Bernstein, Tanja Lange, Peter Schwabe

Basic functions

Public-key cryptography

Signatures A signature (; from la, signare, "to sign") is a handwritten (and often stylized) depiction of someone's name, nickname, or even a simple "X" or other mark that a person writes on documents as a proof of identity and intent. The writer of a ...

using

Ed25519 In public-key cryptography, Edwards-curve Digital Signature Algorithm (EdDSA) is a digital signature scheme using a variant of Schnorr signature based on twisted Edwards curves. It is designed to be faster than existing digital signature scheme ...

. * Key agreement using

X25519 X, or x, is the twenty-fourth and third-to-last letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''"ex"'' (pronounced ), ...

Secret-key cryptography

Authenticated encryption Authenticated Encryption (AE) and Authenticated Encryption with Associated Data (AEAD) are forms of encryption which simultaneously assure the confidentiality and authenticity of data. Programming interface A typical programming interface for ...

using Salsa20-Poly1305. *

Encryption In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can dec ...

using

Salsa20 Salsa20 and the closely related ChaCha are stream ciphers developed by Daniel J. Bernstein. Salsa20, the original cipher, was designed in 2005, then later submitted to the eSTREAM European Union cryptographic validation process by Bernstein. Ch ...

AES AES may refer to: Businesses and organizations Companies * AES Corporation, an American electricity company * AES Data, former owner of Daisy Systems Holland * AES Eletropaulo, a former Brazilian electricity company * AES Andes, formerly AES Gener ...

. *

Authentication Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an assertion, such as the identity of a computer system user. In contrast with identification, the act of indicat ...

using HMAC-SHA-512-256. * One-time authentication using Poly1305.

Low-level functions

* Hashing using

SHA-512 SHA-2 (Secure Hash Algorithm 2) is a set of cryptographic hash functions designed by the United States National Security Agency (NSA) and first published in 2001. They are built using the Merkle–Damgård construction, from a one-way compressi ...

SHA-256 SHA-2 (Secure Hash Algorithm 2) is a set of cryptographic hash functions designed by the United States National Security Agency (NSA) and first published in 2001. They are built using the Merkle–Damgård construction, from a one-way compressi ...

BLAKE2 BLAKE is a cryptographic hash function based on Daniel J. Bernstein's ChaCha stream cipher, but a permuted copy of the input block, XORed with round constants, is added before each ChaCha round. Like SHA-2, there are two variants differing in th ...

using libsodium * String comparison.

Key derivation function (only libsodium)

* Password hashing using argon2

Implementations

Reference implementation is written in C, often with several

inline assembler In computer programming, an inline assembler is a feature of some compilers that allows low-level code written in assembly language to be embedded within a program, among code that otherwise has been compiled from a higher-level language such as ...

. C++ and Python are handled as wrappers. NaCl has a variety of programming language bindings such as PHP, and forms the basis for Libsodium, a cross-platform cryptography library created in 2013 which is API compatible with NaCl.

Alternative implementations

Libsodium
— a portable, cross-compilable, installable, packageable, API-compatible version of NaCl.
dryoc
— a pure-

Rust Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH), ...

implementation of libsodium/NaCl, with support for protected memory. * NaCl Pharo — a Pharo Smalltalk Extension. * TweetNaCl — a tiny C library, which fits in just 100 tweets (140 symbols each), but supports all NaCl functions. * NaCl for Tcl — a port to the Tcl language. * NaCl for JavaScript — a port of TweetNaCl/NaCl cryptographic library to the JavaScript language. * TweetNaCl for Java — a port of TweetNaCl/NaCl cryptographic library to the Java language. * SPARKNaCl — A re-write of TweetNaCl in the SPARK Ada subset, with formal and fully automatic proofs of type safety and some correctness properties. * Crypt::NaCl::Sodium Perl 5 binding to libsodium

References

External links

* {{Official website, https://nacl.cr.yp.to/ Public-domain software Cryptographic software 2008 software