EVP_KDF-PBKDF1(7ossl)

📦
version 15.1 · 3 versions
, in freebsd 15.1

💅 EVP_KDF-PBKDF1 — the PBKDF1 era, but make it OpenSSL

okay so bestie, this is the EVP_KDF-PBKDF1 page from the OpenSSL 7ossl manual set — yes, the whole thing lives in section 7, we love a documentation era 💖

✨ NAME ✨

EVP_KDF-PBKDF1 — the PBKDF1 EVP_KDF implementation, aka the password-based key derivation function that's been doing its thing since forever 🎀

🌸 DESCRIPTION 🌸

So basically, this is the support for computing the PBKDF1 password-based KDF through the EVP_KDF API. Iconic behavior, no notes.

The EVP_KDF-PBKDF1 algorithm implements the PBKDF1 password-based key derivation function, as described in RFC 8018; it derives a key from a password using a salt and iteration count. That's the whole vibe — password goes in, key comes out 💫

🦋 Identity 🦋

"PBKDF1" is the name for this implementation; it can be used with the EVP_KDF_fetch() function. That's your main character name, memorize it iykyk.

🧚 Supported parameters 🧚

The supported parameters are (and yes, we're listing every single one, we don't skip):

  • "pass" (OSSL_KDF_PARAM_PASSWORD) <octet string> — your password, as a raw octet string 🍓
  • "salt" (OSSL_KDF_PARAM_SALT) <octet string> — your salt, same deal, octet string energy
  • "iter" (OSSL_KDF_PARAM_ITER) <unsigned integer> — the iteration count. Heads up: this parameter has a default value of 0 and should be set. Like, please set it, don't just leave it at zero and hope for the best 🙈
  • "properties" (OSSL_KDF_PARAM_PROPERTIES) <UTF8 string> — works exactly as described in "PARAMETERS" in EVP_KDF(3)
  • "digest" (OSSL_KDF_PARAM_DIGEST) <UTF8 string> — same, works as described in "PARAMETERS" in EVP_KDF(3)

🔥 NOTES 🔥

A typical application of this algorithm is to derive keying material for an encryption algorithm from a password in the "pass", a salt in "salt", and an iteration count. Very "put it all in a blender and get a key out" of it all tbh 🫶

Increasing the "iter" parameter slows down the algorithm which makes it harder for an attacker to perform a brute force attack using a large number of candidate passwords. So yeah — bigger iter, more pain for the bad guys, that's the point 💅

No assumption is made regarding the given password; it is simply treated as a byte sequence. It's not judging your password, it's just bytes, fr fr.

⚠️ side note bestie: the legacy provider needs to be available in order to access this algorithm. No legacy provider, no PBKDF1, periodt.

👑 CONFORMING TO 👑

RFC 8018 — that's the one, she's certified ✨

🌈 SEE ALSO 🌈

Go read these, they're all part of the lore:

⭐ HISTORY ⭐

This functionality was added in OpenSSL 3.0 — so it's giving "newer than you think" 💀

Copyright 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>.

okay that's the whole page, no cap, every flag and every name intact 💖 this was version 3.5.6, dated 2026-04-07, straight from your fave EVP_KDF-PBKDF1(7ossl) era — slay, now go derive some keys responsibly 🎀🌷

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