PKCS8_PKEY_ADD1_ATTR(3ossl)

💖 PKCS8_PKEY_ADD1_ATTR 💖

okay bestie, welcome to the 3ossl corner of the OpenSSL manual — this one's all about the PKCS8 attribute functions and honestly it's lowkey iconic once you get the vibe ✨

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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, fr fr 💅

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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);

like, just look at that signature block, it's giving structured-and-ready 🎀

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✨ DESCRIPTION ✨

So here's the tea, one function at a time 🍓

• PKCS8_pkey_get0_attrs() — hands you back a const STACK of X509_ATTRIBUTE that's chillin' inside the const PKCS8_PRIV_KEY_INFO structure you passed as p8. that's it, that's the whole job 💜
• PKCS8_pkey_add1_attr() — takes an already-constructed X509_ATTRIBUTE called attr and adds it to the existing PKCS8_PRIV_KEY_INFO structure p8. you built the attribute, now you're sliding it in 🫶
• PKCS8_pkey_add1_attr_by_NID() and PKCS8_pkey_add1_attr_by_OBJ() — these two are the DIY girlies: they construct a brand-new X509_ATTRIBUTE straight from the arguments you pass in, then add it to the existing PKCS8_PRIV_KEY_INFO structure p8. no pre-made attribute needed, they craft it on the spot ✨

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🔥 RETURN VALUES 🔥

PKCS8_pkey_add1_attr(), PKCS8_pkey_add1_attr_by_NID(), and PKCS8_pkey_add1_attr_by_OBJ() return 1 for success and 0 for failure. that's the whole vibe check — 1 slay, 0 not slay 😭

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👑 NOTES 👑

STACK of X509_ATTRIBUTE shows up in so many X509-related structures, and some of those structures have their own matching set of similar functions. so if you've seen this pattern before, you're not trippin' — it's a whole family thing, iykyk 💫

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🌈 SEE ALSO 🌈

• crypto(7) — go read it, bestie, it's the lore 🧚

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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>.

okay but fr fr, read the license before you go copying this around — it's not a suggestion, it's the rules 💅

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and that's the whole page, bestie!! 🎀 huge thank you to the OpenSSL squad for version 3.5.0, dated 2026-09-25 — go off kings, we love a documented cryptographic API 🌸💖✨