HMAC256(1)

🎀 HMAC256(1) — Libgcrypt's manual page, bestie 🎀

💖 NAME 💖

hmac256 — Compute an HMAC-SHA-256 MAC. That's literally the whole assignment ✨

🦋 SYNOPSIS 🦋

hmac256 [--binary] key [FILENAME]

🌸 DESCRIPTION 🌸

okay so hmac256 is a standalone HMAC-SHA-256 implementation used to compute an HMAC-SHA-256 message authentication code. iconic behavior, fr fr.

It was originally developed as a second implementation for Libgcrypt so you can compare it against the primary implementation and use it for internal consistency checks. slay for that specific job, ngl.

🚨 big warning bestie: it should not be used for sensitive data because no mechanisms to clear the stack etc are used. like, this is not giving secure-vault main character energy. periodt.

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. lowkey cute, highkey portable.

hmac256 is commonly invoked as

hmac256 "This is my key" foo.txt

This computes the MAC on the file foo.txt using the key given on the command line. yes bestie, key on the command line, file on the side 💅

✨ 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. bye 👋

🔥 SEE ALSO 🔥

sha256sum(1)

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okay bye bestie — this page's source/version is Libgcrypt 1.12.2-unknown and its date is 2026-04-16. stay iconic 💖🫶🎀