EVP_MD-SHA1(7ossl)

💅 EVP_MD-SHA1 ✨

okay so bestie, welcome to the EVP_MD-SHA1(7ossl) page — yes that 7ossl is the manual name, it's the OpenSSL section 7 vibe, we love a filing system 🎀

🌸 NAME 🌸

EVP_MD-SHA1 — the SHA1 EVP_MD implementation, aka the whole entire point of this page 💖

🦋 DESCRIPTION 🦋

So this is the support for computing SHA1 digests through the EVP_MD API. That's the tea. 🍵

✨ Identities ✨

This implementation is available with the FIPS provider as well as the default provider, and it's identified with the names "SHA1" and "SHA-1". Two names, same iconic digest — she answers to both, no cap 💅

🎀 Gettable Parameters 🎀

This implementation supports the common gettable parameters described in EVP_MD-common(7). Go read that one for the deets, iykyk 🫶

🔥 Settable Context Parameters 🔥

This implementation supports the following OSSL_PARAM(3) entries, settable for an EVP_MD_CTX with EVP_MD_CTX_set_params(3):

• "ssl3-ms" (OSSL_DIGEST_PARAM_SSL3_MS) <octet string> — okay so this parameter gets set by libssl in order to calculate a signature hash for an SSLv3 CertificateVerify message as per RFC6101. It is only set after all handshake messages have already been digested via OP_digest_update() calls. The parameter provides the master secret value to be added to the digest. The digest implementation should calculate the complete digest as per RFC6101 section 5.6.8. And listen — the next call after setting this parameter should be OP_digest_final(). That's the rule, periodt ⭐

not me being dramatic but like... respect the ordering bestie, OP_digest_final() is literally the next call, that's the whole vibe check 😭

👑 SEE ALSO 👑

EVP_MD_CTX_set_params(3), provider-digest(7), OSSL_PROVIDER-FIPS(7), OSSL_PROVIDER-default(7)

🌈 COPYRIGHT 🌈

Copyright 2020 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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and that's the page babes 💜 sign-off time: this was version 3.5.9, dated 2026-09-29, and yes the title really is EVP_MD-SHA1(7ossl) — she ate, she slayed, she digested 🧚‍♀️💖