NAME

b2sum — generate checksums using the BLAKE2 hash function

SYNOPSIS

DESCRIPTION

The b2sum command generates checksums for files using the BLAKE2 cryptographic hash function and writes them to standard output.

When [file ...] is empty or -, b2sum reads from standard input.

-a algorithm

Specify a variant of BLAKE2 to use when generating checksums. The variants are listed under the algorithms section, and the default is blake2b.

-l length

Specify the digest length in bits. It must not exceed the maximum for the variant of BLAKE2 being used, and must be a multiple of 8.

--tag

Prepend the checksums with "ALGORITHM-NAME (file) =", a format common on BSD systems.

--help

Display usage.

ALGORITHMS

blake2b

optimized for 64-bit platforms and NEON-enabled ARMs, produces digests of any size between 1 and 64 bytes

blake2s

optimized for 8 to 32-bit platforms, produces digests of any size between 1 and 32 bytes

blake2bp

4-way parallel BLAKE2b

blake2sp

8-way parallel BLAKE2s

SEE ALSO

shasum(1)

STANDARDS

RFC 7693

The BLAKE2 Cryptographic Hash and Message Authentication Code

AUTHORS

b2sum is part of the BLAKE2 official implementation. BLAKE2 was designed by Jean-Philippe Aumasson, Samuel Neves, Zooko Wilcox-O'Hearn, and Christian Winnerlein.

BLAKE2 is based on the SHA-3 proposal BLAKE which was designed by Jean-Philippe Aumasson, Luca Henzen, Willi Meier, and Raphael C.-W. Phan.

BLAKE2, like BLAKE, relies on the ChaCha20 stream cipher, designed by Daniel J. Bernstein.

A mailing list for BLAKE2 can be subscribed to by sending an empty message to info-subscribe@blake2.net.

The four designers of BLAKE2 can be contacted at contact@blake2.net.

This manual page was written by Scarlett.