SSL_CTX_SET_TMP_ECDH(3ossl)

🌸 NAME 🌸

okay bestie, welcome to the SSL_CTX_SET_TMP_ECDH(3ossl) page — yes, that’s the manual name, right up top, no cap ✨. This one covers:

• SSL_CTX_set_tmp_ecdh
• SSL_set_tmp_ecdh
• SSL_CTX_set_ecdh_auto
• SSL_set_ecdh_auto

and their whole thing is handle ECDH keys for ephemeral key exchange 💅.

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🌈 SYNOPSIS 🌈

#include <openssl/ssl.h>

long SSL_CTX_set_tmp_ecdh(SSL_CTX *ctx, const EC_KEY *ecdh);
long SSL_set_tmp_ecdh(SSL *ssl, const EC_KEY *ecdh);

long SSL_CTX_set_ecdh_auto(SSL_CTX *ctx, int state);
long SSL_set_ecdh_auto(SSL *ssl, int state);

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💖 DESCRIPTION 💖

SSL_CTX_set_tmp_ecdh() sets the ECDH parameters to be ecdh. The key is inherited by all ssl objects created from ctx — like, every little SSL gets the same inherited vibe ✨. Heads up though: this macro is deprecated in favor of SSL_CTX_set1_groups(3) 😭.

SSL_set_tmp_ecdh() sets the parameters only for ssl. This macro is deprecated in favor of SSL_set1_groups(3).

SSL_CTX_set_ecdh_auto() and SSL_set_ecdh_auto() are deprecated and have no effect. Literally none, bestie — decorative-only energy 💀.

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🎀 RETURN VALUES 🎀

SSL_CTX_set_tmp_ecdh() and SSL_set_tmp_ecdh() return 1 on success and 0 on failure. That’s the whole vibe check, periodt 💅.

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🦋 SEE ALSO 🦋

• ssl(7)
• SSL_CTX_set1_curves(3)
• SSL_CTX_set_cipher_list(3)
• SSL_CTX_set_options(3)
• SSL_CTX_set_tmp_dh_callback(3)
• openssl-ciphers(1)
• openssl-ecparam(1)

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👑 COPYRIGHT 👑

Copyright 2018 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>.

OpenSSL 3.5.6 🌈 2026-04-07 🌈 that’s the source/version + date, bestie — slay 💅