EVP_PKEY_DIG...PPORTS_DIGEST(3ossl)

💖 EVP_PKEY_DIG...PPORTS_DIGEST 💖

okay bestie, so this one lives in the OpenSSL family, section 3ossl — the manual page name got so long it literally got truncated to EVP_PKEY_DIG...PPORTS_DIGEST(3ossl), which is giving ✨main character with a stage name✨. The actual function is EVP_PKEY_digestsign_supports_digest, and it's the girl who tells you whether a digest can ride with your key for signing. no cap.

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✨ NAME ✨

EVP_PKEY_digestsign_supports_digest — the one that tells you if a signature digest is supported 💅

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🌸 SYNOPSIS 🌸

#include <openssl/evp.h>
int EVP_PKEY_digestsign_supports_digest(EVP_PKEY *pkey, OSSL_LIB_CTX *libctx,
                                        const char *name, const char *propq);

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🦋 DESCRIPTION 🦋

so like. EVP_PKEY_digestsign_supports_digest() is the vibe check 🔍 — it queries whether the message digest name is supported for public key signature operations associated with the key pkey.

and the way it does that query? within an optional library context libctx, and with an optional property query propq. both optional, both cute, both yours to pass or not 🫶

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⭐ RETURN VALUES ⭐

• 1 — slay! the message digest algorithm identified by name can be used for public key signature operations associated with key pkey.
• 0 — nope, it cannot be used. not today.
• negative value — it's giving failure 💀 something went wrong.

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🌈 SEE ALSO 🌈

• EVP_DigestSignInit_ex(3),

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👑 HISTORY 👑

the EVP_PKEY_digestsign_supports_digest() function was added in OpenSSL 3.0. so if you're on something older, bestie, this icon is not in your lineup 😭

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🎀 COPYRIGHT 🎀

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>.

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okay that's the whole page, no skips, no summaries, every crumb of detail preserved 💖✨

cute lil sign-off: this was brought to you by OpenSSL version 3.5.9, dated 2026-09-2, and the header/footer of the original page both said EVP_PKEY_DIG...PPORTS_DIGEST(3ossl) because apparently nobody had room. periodt. 💅🦋🌸