nacl: nacl

NaCl - Networking and Cryptography library (pronounced "salt")

Sysnopsis

    nacl::info
    nacl::randombytes names
    nacl::randombytes source ?random|urandom|secrandomcopybytes|cryptgenrandom|default?
    nacl::randombytes lengthValue
    nacl::randombytes box ?-nonce?
    nacl::randombytes scalarmult ?-scalar|-group?
    nacl::randombytes secretbox ?-nonce|-key?
    nacl::randombytes stream ?-nonce|-key?
    nacl::randombytes auth ?-key?
    nacl::randombytes onetimeauth ?-key?

Public-key cryptography

    nacl::box info
    nacl::box keypair publicKeyVariable secretKeyVariable
    nacl::box cipherVariable messageValue nonceValue publicKeyValue secretKeyValue
    nacl::box open messageVariable cipherValue nonceValue publicKeyValue secretKeyValue
    nacl::scalarmult info
    nacl::scalarmult resultVariable scalarValue groupValue
    nacl::scalarmult base resultVariable scalarValue
    nacl::sign info
    nacl::sign keypair publicKeyVariable secretKeyVariable
    nacl::sign signedVariable messageValue secretKeyValue
    nacl::sign verify messageVariable signedValue publicKeyValue

Secret-key cryptography

    nacl::secretbox info
    nacl::secretbox cipherVariable messageValue nonceValue keyValue
    nacl::secretbox open messageVariable cipherValue nonceValue keyValue
    nacl::stream info
    nacl::stream generate cipherVariable nonceValue keyValue
    nacl::stream cipherVariable messageValue nonceValue keyValue
    nacl::auth info
    nacl::auth ?-hmac256|-hmac512256? authVariable messageValue keyValue
    nacl::auth verify -hmac256|-hmac512256 authValue messageValue keyValue
    nacl::onetimeauth info
    nacl::onetimeauth authVariable messageValue keyValue
    nacl::onetimeauth verify authValue messageValue keyValue

Low-level functions

    nacl::hash info
    nacl::hash ?-sha256|-sha512? hashVariable messageValue

Description

NaCl (pronounced "salt") is a new easy-to-use high-speed software library for network communication, encryption, decryption, signatures, etc. NaCl's goal is to provide all of the core operations needed to build higher-level cryptographic tools. Of course, other libraries already exist for these core operations. NaCl advances the state of the art by improving security, by improving usability, and by improving speed.

Key features

No data flow from secrets to load addresses. No data flow from secrets to branch conditions. No padding oracles. Centralizing randomness. Avoiding unnecessary randomness. Extremely high speed.

Functions supported

Simple NaCl applications need only six high-level NaCl functions: crypto_box for public-key authenticated encryption; crypto_box_open for verification and decryption; crypto_box_keypair to create a public key in the first place; and similarly for signatures crypto_sign, crypto_sign_open, and crypto_sign_keypair.

A minimalist implementation of the NaCl API would provide just these six functions. TweetNaCl is more ambitious, supporting all 25 of the NaCl functions listed below, which as mentioned earlier are all of the C NaCl functions used by applications. This list includes all of NaCl's "default" primitives except for crypto_auth_hmacsha512256, which was included in NaCl only for compatibility with standards and is superseded by crypto_onetimeauth.

The Ed25519 signature system has not yet been integrated into NaCl, since the Ed25519 software has not yet been fully audited; NaCl currently provides an older signature system. However, NaCl has announced that it will transition to Ed25519, so TweetNaCl provides Ed25519.

Public-key cryptography

Authenticated encryption using Curve25519, Salsa20, and Poly1305

crypto_box = crypto_box_curve25519xsalsa20poly1305
Not implemented: crypto_box_beforenm + crypto_box_afternm
crypto_scalarmult = crypto_scalarmult_curve25519

Signatures using Ed25519

crypto_sign = crypto_sign_ed25519

Secret-key cryptography

Authenticated encryption using Salsa20 and Poly1305

crypto_secretbox = crypto_secretbox_xsalsa20poly1305

Encryption using Salsa20

crypto_stream = crypto_stream_xsalsa20

Authentication using HMAC-SHA-512-256

crypto_auth_hmacsha256_ref, crypto_auth_hmacsha512256_ref

One-time authentication using Poly1305

crypto_onetimeauth = crypto_onetimeauth_poly1305

Low-level functions

Hashing using SHA-512 or SHA-256

crypto_hash_sha256_ref, crypto_hash = crypto_hash_sha512

Wiki Pages

Legal Notice

NaCl and TweetNaCl crypto library are public domain and the Tcl package BSD-3 license

Contributors (alphabetical order)

Daniel J. Bernstein, University of Illinois at Chicago and Technische Universiteit Eindhoven
Bernard van Gastel, Radboud Universiteit Nijmegen
Wesley Janssen, Radboud Universiteit Nijmegen
Tanja Lange, Technische Universiteit Eindhoven
Peter Schwabe, Radboud Universiteit Nijmegen
Sjaak Smetsers, Radboud Universiteit Nijmegen

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