EVP_KDF-X942-CONCAT(7ossl)

💅 NAME 💅

EVP_KDF-X942-CONCAT — the X942 Concat EVP_KDF implementation, bestie. That's the whole vibe. It's the OpenSSL man page EVP_KDF-X942-CONCAT(7ossl), and yes we're getting into it.

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✨ DESCRIPTION ✨

okay so here's the tea 🫖 — the EVP_KDF-X942-CONCAT algorithm is literally identical to EVP_KDF-X963. Like, not "similar", not "cousin energy", identical. Periodt.

What's it for? Key agreement, babes 💖 — it derives a key using input such as a shared secret key and shared info. That's the whole gig. No cap.

🎀 Identity 🎀

"X942KDF_CONCAT" is the name for this implementation, and you can use it with the EVP_KDF_fetch() function. Iconic string, memorize it 💅

It's also an alias for "X963KDF" — so like, same energy, different name tag.

👑 Heads up bestie: see EVP_KDF-X963(7) for a list of supported parameters and examples. That's where the actual parameter deets live — I'm not out here making stuff up, fr fr.

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🌸 HISTORY 🌸

This functionality was added in OpenSSL 3.0. Vintage but still slaying ✨

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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. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>.

🚨 Real talk: don't just use this file and ignore the License — that's not the move. Read it, respect it, then go derive those keys 🫶

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and that's the whole page, bestie 🦋 mwah 💋 — this was EVP_KDF-X942-CONCAT(7ossl), version 3.5.9, dated 2026-09-29. go forth and fetch your KDF 🌈⭐