B2I_PVK_BIO_EX(3ossl)

📦 version 3.5.0, in opensuse-leap 16.0

✨ B2I_PVK_BIO_EX ✨

okay so bestie, welcome to the 3ossl corner of the OpenSSL manual — this one is all about b2i_PVK_bio, b2i_PVK_bio_ex, i2b_PVK_bio and i2b_PVK_bio_ex, the four little functions that decode and encode MSBLOB format private keys. yes, the decode and encode functions for reading and writing MSBLOB format private keys. we love a bidirectional icon 💅

🌸 SYNOPSIS 🌸

#include <openssl/pem.h>

EVP_PKEY *b2i_PVK_bio(BIO *in, pem_password_cb *cb, void *u);
EVP_PKEY *b2i_PVK_bio_ex(BIO *in, pem_password_cb *cb, void *u,
                         OSSL_LIB_CTX *libctx, const char *propq);
int i2b_PVK_bio(BIO *out, const EVP_PKEY *pk, int enclevel,
                pem_password_cb *cb, void *u);
int i2b_PVK_bio_ex(BIO *out, const EVP_PKEY *pk, int enclevel,
                   pem_password_cb *cb, void *u,
                   OSSL_LIB_CTX *libctx, const char *propq);

🦋 DESCRIPTION 🦋

so the b2i girlies read, and the i2b girlies write — it's giving two sides of the same coin, honestly 💖

🎀 The decoding side (b2i, b2i_ex)

b2i_PVK_bio_ex() decodes a private key of MSBLOB format read from a BIO. it's lowkey a mind reader — it attempts to automatically determine the key type. no cap.

if the key is encrypted, then cb gets called with the user data u so it can obtain a password to decrypt the key. and the supplied library context libctx and property query string propq are used in any decrypt operation. teamwork, bestie 🫶

b2i_PVK_bio() does the same as b2i_PVK_bio_ex() except that the default library context and property query string are used. the vibes-only version, no custom context needed ✨

🌈 The encoding side (i2b, i2b_ex)

i2b_PVK_bio_ex() encodes pk using MSBLOB format. now the enclevel situation:

  • if enclevel is 1 then a password obtained via pem_password_cb is used to encrypt the private key 🔥
  • if enclevel is 0 then no encryption is applied 🙈

the user data in u is passed to the password callback. and (same as always) the supplied library context libctx and property query string propq are used in any decrypt operation.

i2b_PVK_bio() does the same as i2b_PVK_bio_ex() except that the default library context and property query string are used. twins, basically 💜

💀 RETURN VALUES 💀

b2i_PVK_bio() and b2i_PVK_bio_ex() return a valid EVP_KEY structure, or NULL if an error occurs. if you're staring at a NULL like 😭, the error code can be obtained by calling ERR_get_error(3).

i2b_PVK_bio() and i2b_PVK_bio_ex() return the number of bytes successfully encoded, or a negative value if an error occurs. and again — the error code can be obtained by calling ERR_get_error(3) 🕵️

🧚 SEE ALSO 🧚

go read those next, iykyk 📚

👑 HISTORY 👑

b2i_PVK_bio_ex() and i2b_PVK_bio_ex() were added in OpenSSL 3.0. the _ex glow-up is honestly iconic 🌟

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>.

fr fr read the license before you ship anything, bestie — it's not a suggestion 💅

and that's the whole page! mwah 💖 — this little masterpiece is from OpenSSL 3.5.0, dated 2026-09-25, and it lives at B2I_PVK_BIO_EX(3ossl). periodt. 🎀

📦 where this page comes from