EVP_PKEY_SETTABLE_PARAMS(3ossl)

💖 EVP_PKEY_SETTABLE_PARAMS 💖

okay bestie, so this is a page from the OpenSSL manual, section 3ossl, and it's all about cramming extra key parameters into a key you already have. no cap, it's lowkey iconic. let's go 🦋

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✨ NAME ✨

EVP_PKEY_settable_params, EVP_PKEY_set_params, EVP_PKEY_set_int_param, EVP_PKEY_set_size_t_param, EVP_PKEY_set_bn_param, EVP_PKEY_set_utf8_string_param, EVP_PKEY_set_octet_string_param — these are the girlies that set key parameters into a key 💅

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✨ SYNOPSIS ✨

#include <openssl/evp.h>

const OSSL_PARAM *EVP_PKEY_settable_params(const EVP_PKEY *pkey);
int EVP_PKEY_set_params(EVP_PKEY *pkey, OSSL_PARAM params[]);
int EVP_PKEY_set_int_param(EVP_PKEY *pkey, const char *key_name, int in);
int EVP_PKEY_set_size_t_param(EVP_PKEY *pkey, const char *key_name, size_t in);
int EVP_PKEY_set_bn_param(EVP_PKEY *pkey, const char *key_name,
                          const BIGNUM *bn);
int EVP_PKEY_set_utf8_string_param(EVP_PKEY *pkey, const char *key_name,
                                   const char *str);
int EVP_PKEY_set_octet_string_param(EVP_PKEY *pkey, const char *key_name,
                                    const unsigned char *buf, size_t bsize);

like. look at them. all lined up. main character energy fr fr 👑

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✨ DESCRIPTION ✨

so basically? these functions let you set additional parameters into an existing EVP_PKEY. not a new one, an existing one. she's already here, we're just adding to her vibe ✨

EVP_PKEY_set_params() sets one or more params into a pkey. want the tea on parameters? go read OSSL_PARAM(3), she explains everything 🫶

EVP_PKEY_settable_params() returns a constant list of params showing the names and types of key parameters that can actually be set. so it's like the guest list — who's allowed in, what they look like. again, OSSL_PARAM(3) has the details on parameters 💖

EVP_PKEY_set_int_param() sets an integer value in into a key pkey for the associated field key_name. 🍓

EVP_PKEY_set_size_t_param() sets a size_t value in into a key pkey for the associated field key_name. 🌸

EVP_PKEY_set_bn_param() sets the BIGNUM value bn into a key pkey for the associated field key_name. big number, big slay 💅

EVP_PKEY_set_utf8_string_param() sets the UTF8 string str into a key pkey for the associated field key_name. 🎀

EVP_PKEY_set_octet_string_param() sets the octet string value buf with a size bsize into a key pkey for the associated field key_name. 🌈

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✨ NOTES ✨

⚠️ okay important, listen up bestie: these functions only work for EVP_PKEYs that contain a provider side key. if yours doesn't? she's not coming to the party, sorry 😭

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✨ RETURN VALUES ✨

• EVP_PKEY_settable_params() returns NULL on error, or if it is not supported. 💀
• All the other methods return 1 if a value was successfully set, or 0 if there was an error. ✨

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✨ SEE ALSO ✨

• EVP_PKEY_gettable_params(3)
• EVP_PKEY_CTX_new(3)
• provider-keymgmt(7)
• OSSL_PARAM(3)

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✨ HISTORY ✨

these functions were added in OpenSSL 3.0. so they're not ancient artifacts, they're modern queens 👑

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✨ COPYRIGHT ✨

Copyright 2020-2021 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>.

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okay that's the whole page, you ate that 🫶 this was OpenSSL 3.5.9, dated 2026-09-29, and it's the EVP_PKEY_SETTABLE_PARAMS(3ossl) page — go set some params, bestie, you got this 💖✨