PKCS8_PKEY_ADD1_ATTR(3SSL)

💖 PKCS8_PKEY_ADD1_ATTR 💖

okay bestie, welcome to the PKCS8_PKEY_ADD1_ATTR(3SSL) page — this is the OpenSSL fam of functions that handle attributes living inside a PKCS8_PRIV_KEY_INFO (aka your PKCS#8 private key info vibe). it's short, it's sweet, it's giving "small API, big responsibilities" ✨

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🦋 NAME 🦋

PKCS8_pkey_get0_attrs, PKCS8_pkey_add1_attr, PKCS8_pkey_add1_attr_by_NID, PKCS8_pkey_add1_attr_by_OBJ — the PKCS8 attribute functions 💅

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🌸 SYNOPSIS 🌸

#include <openssl/x509.h>

const STACK_OF(X509_ATTRIBUTE) *
PKCS8_pkey_get0_attrs(const PKCS8_PRIV_KEY_INFO *p8);
int PKCS8_pkey_add1_attr(PKCS8_PRIV_KEY_INFO *p8, X509_ATTRIBUTE *attr);
int PKCS8_pkey_add1_attr_by_NID(PKCS8_PRIV_KEY_INFO *p8, int nid, int type,
                                const unsigned char *bytes, int len);
int PKCS8_pkey_add1_attr_by_OBJ(PKCS8_PRIV_KEY_INFO *p8, const ASN1_OBJECT *obj,
                               int type, const unsigned char *bytes, int len);

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👑 DESCRIPTION 👑

so here's the tea, function by function 🍓

• PKCS8_pkey_get0_attrs() — this one hands you back a const STACK of X509_ATTRIBUTE that's chillin' inside the const PKCS8_PRIV_KEY_INFO you passed in as p8. it's a getter, she's just looking, not touching, periodt.
• PKCS8_pkey_add1_attr() — this girl takes a constructed X509_ATTRIBUTE called attr and adds it to the existing PKCS8_PRIV_KEY_INFO structure p8. you already built the attribute, she just moves it in 🫶
• PKCS8_pkey_add1_attr_by_NID() and PKCS8_pkey_add1_attr_by_OBJ() — these two are the DIY queens 💅 they construct a brand new X509_ATTRIBUTE from the arguments you hand over and add it to the existing PKCS8_PRIV_KEY_INFO structure p8. so like, you give the ingredients, they plate it up and serve it. iconic behaviour, no cap.

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⭐ RETURN VALUES ⭐

PKCS8_pkey_add1_attr(), PKCS8_pkey_add1_attr_by_NID(), and PKCS8_pkey_add1_attr_by_OBJ() are out here being real simple: they return 1 for success and 0 for failure. that's it. binary. main character energy, truly 💀

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✨ NOTES ✨

a STACK of X509_ATTRIBUTE is literally everywhere in X509-related structures — it's the social butterfly of the ASN.1 world 🦋 and lowkey, some of those other structures have their own matching set of similar functions. so if you've seen this pattern before somewhere else, you're not trippin', iykyk.

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🌈 SEE ALSO 🌈

• crypto(7)

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🎀 COPYRIGHT 🎀

Copyright 2020 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>.

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💜 bestie that's a wrap! this page was living in version 4.0.3, dated 2026-09-29, and yes she's officially filed under PKCS8_PKEY_ADD1_ATTR(3SSL). go forth and slay those attributes ✨🧚💖