EVP_PKEY2PKCS8(3ossl)

📦 version 3.5.0, in opensuse-leap 16.0

💖 EVP_PKEY2PKCS8 — aka the glow-up page (OpenSSL, 3ossl manual) 💖

okay bestie, gather round, because this is the page where your private key gets a whole new outfit ✨ This is the 3ossl section of the OpenSSL docs, so you already know it's about library functions and not some command you type into a shell. slay.

🎀 NAME 🎀

EVP_PKEY2PKCS8, EVP_PKCS82PKEY_ex, EVP_PKCS82PKEY — the little trio that converts a private key to/from PKCS8. literally their whole job 💅

🌸 SYNOPSIS 🌸

the includes, iconically:

#include <openssl/x509.h>

and the three function besties, exactly as declared:

PKCS8_PRIV_KEY_INFO *EVP_PKEY2PKCS8(const EVP_PKEY *pkey);
EVP_PKEY *EVP_PKCS82PKEY(const PKCS8_PRIV_KEY_INFO *p8);
EVP_PKEY *EVP_PKCS82PKEY_ex(const PKCS8_PRIV_KEY_INFO *p8, OSSL_LIB_CTX *libctx,
                            const char *propq);

🦋 DESCRIPTION 🦋

so here's the tea ☕

  • EVP_PKEY2PKCS8() — takes a private key pkey and converts it into a returned PKCS8 object. it's giving ✨transformation✨
  • EVP_PKCS82PKEY_ex() — goes the other way: takes a PKCS8 object p8 and converts it into a returned private key. it uses libctx and propq when fetching algorithms. iykyk, those are your library context and property query vibes 🫶
  • EVP_PKCS82PKEY() — basically the same as EVP_PKCS82PKEY_ex() but with the default values of NULL for the libctx and propq. lowkey the chill, no-frills version 😌

👑 RETURN VALUES 👑

okay so what do you actually get back:

  • EVP_PKEY2PKCS8() returns a PKCS8 object on success. periodt.
  • EVP_PKCS82PKEY() and EVP_PKCS82PKEY_ex() return a private key on success. iconic behavior.
⚠️ and the important bit, bestie: all functions return NULL if the operation fails. so if you see NULL, that's your vibe check failing — handle it, don't ignore it 😭

🔥 SEE ALSO 🔥

(yes, that trailing comma is canon, don't come for me 💀)

Copyright 2020-2022 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>.

and that's the whole page, bestie, no cap 🧚✨

cute little sign-off for you: this masterpiece is from OpenSSL version 3.5.0, dated 2026-09-25, and it lives in the EVP_PKEY2PKCS8(3ossl) corner of the universe 💖 go forth and convert those keys 🎀

📦 where this page comes from