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HMAC256(1) Libgcrypt HMAC256(1)
NAME
hmac256 - Compute an HMAC-SHA-256 MAC
SYNOPSIS
hmac256 [--binary] key [FILENAME]
DESCRIPTION
This is a standalone HMAC-SHA-256 implementation used to compute an
HMAC-SHA-256 message authentication code. The tool has originally been
developed as a second implementation for Libgcrypt to allow comparing
against the primary implementation and to be used for internal
consistency checks. It should not be used for sensitive data because
no mechanisms to clear the stack etc are used.
The code has been written in a highly portable manner and requires only
a few standard definitions to be provided in a config.h file.
hmac256 is commonly invoked as
hmac256 "This is my key" foo.txt
This compute the MAC on the file `foo.txt' using the key given on the
command line.
OPTIONS
hmac256 understands these options:
--binary
Print the MAC as a binary string. The default is to print the
MAC encoded as lower case hex digits.
--version
Print version of the program and exit.
SEE ALSO
sha256sum(1)
Libgcrypt 1.10.2 2023-12-14 HMAC256(1)