EVP_KDF-X942-CONCAT(7SSL)

💖 NAME 💖

EVP_KDF-X942-CONCAT — the X942 Concat EVP_KDF implementation, bestie, and she's serving.

This one's from the OpenSSL manuals, section 7SSL. Pull up a chair 🫶

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✨ DESCRIPTION ✨

Okay so real talk first: the EVP_KDF-X942-CONCAT algorithm is literally identical to EVP_KDF-X963. Same girl, different name tag 💅

What's she for? Key agreement, babes. She derives a key using input like a shared secret key and some shared info. That's the whole vibe.

🔑 Identity

"X942KDF_CONCAT" is the name for this implementation — that's the string you hand over to the EVP_KDF_fetch() function.

She's also an alias for "X963KDF", no cap.

And because they're the same algorithm under the hood, go check EVP_KDF-X963(7) for the full list of supported parameters and examples 👑 (that's where all the juicy deets live).

Not me telling you to read the sibling manpage for the actual options, but like… that's genuinely where they are. Fr fr.

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🌈 HISTORY 🌈

This functionality was added in OpenSSL 3.0. Iconic behavior, honestly.

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🎀 COPYRIGHT 🎀

Copyright 2020-2021 The OpenSSL Project Authors. All Rights Reserved. 📝

Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the License. Bestie, the License is not optional — respect the rules 🙈

You can obtain a copy in the file LICENSE in the source distribution, or at:

https://www.openssl.org/source/license.html

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and that's the whole page, my love ✨ thanks for reading all the way through, you ate 🍓

signing off from version 4.0.3, dated 2026-09-29 — EVP_KDF-X942-CONCAT(7SSL), periodt 💜🦋