PKCS8_decrypt, PKCS8_decrypt_ex, PKCS8_encrypt, PKCS8_encrypt_ex, PKCS8_set0_pbe, PKCS8_set0_pbe_ex -

       IETF RFC 7292 (<https://tools.ietf.org/html/rfc7292>)

       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>.

3.5.0                                              2025-06-04                                PKCS8_ENCRYPT(3SSL)

PKCS8_encrypt() and PKCS8_encrypt_ex() perform encryption of an object p8 using the password pass of
       length passlen, salt salt of length saltlen and iteration count iter.  The resulting X509_SIG contains
       the encoded algorithm parameters and encrypted key.

       PKCS8_decrypt() and PKCS8_decrypt_ex() perform decryption of an X509_SIG in p8 using the password pass of
       length passlen along with algorithm parameters obtained from the p8.

       PKCS8_set0_pbe() and PKCS8_set0_pbe_ex() perform encryption of the p8inf using the password pass of
       length passlen and parameters pbe.

       Functions ending in _ex() allow for a library context ctx and property query propq to be used to select
       algorithm implementations.

PKCS8_decrypt_ex(), PKCS8_encrypt_ex() and PKCS8_set0_pbe_ex() were added in OpenSSL 3.0.

       PKCS8_decrypt, PKCS8_decrypt_ex, PKCS8_encrypt, PKCS8_encrypt_ex, PKCS8_set0_pbe, PKCS8_set0_pbe_ex -
       PKCS8 encrypt/decrypt functions

PKCS8_encrypt(), PKCS8_encrypt_ex(), PKCS8_set0_pbe() and PKCS8_set0_pbe_ex() return an encrypted key in
       a X509_SIG structure or NULL if an error occurs.

       PKCS8_decrypt() and PKCS8_decrypt_ex() return a PKCS8_PRIV_KEY_INFO or NULL if an error occurs.

crypto(7)

        #include <openssl/x509.h>

        PKCS8_PRIV_KEY_INFO *PKCS8_decrypt(const X509_SIG *p8, const char *pass,
                                           int passlen);
        PKCS8_PRIV_KEY_INFO *PKCS8_decrypt_ex(const X509_SIG *p8, const char *pass,
                                              int passlen, OSSL_LIB_CTX *ctx,
                                              const char *propq);
        X509_SIG *PKCS8_encrypt(int pbe_nid, const EVP_CIPHER *cipher,
                                const char *pass, int passlen, unsigned char *salt,
                                int saltlen, int iter, PKCS8_PRIV_KEY_INFO *p8);
        X509_SIG *PKCS8_encrypt_ex(int pbe_nid, const EVP_CIPHER *cipher,
                                   const char *pass, int passlen, unsigned char *salt,
                                   int saltlen, int iter, PKCS8_PRIV_KEY_INFO *p8,
                                   OSSL_LIB_CTX *ctx, const char *propq);
        X509_SIG *PKCS8_set0_pbe(const char *pass, int passlen,
                                PKCS8_PRIV_KEY_INFO *p8inf, X509_ALGOR *pbe);
        X509_SIG *PKCS8_set0_pbe_ex(const char *pass, int passlen,
                                    PKCS8_PRIV_KEY_INFO *p8inf, X509_ALGOR *pbe,
                                    OSSL_LIB_CTX *ctx);