EVP_CIPHER-NULL(7ossl)

📦
version 3.5.9 · 8 versions
, in alpine 3.23, alpine 3.24

💅 EVP_CIPHER-NULL — the NULL EVP_CIPHER implementation 🎀

Okay so bestie, welcome to EVP_CIPHER-NULL(7ossl) from the OpenSSL fam — this is the manual page for the NULL cipher and it's literally the chillest crypto thing ever. Let's get into it ✨

✨ NAME ✨

EVP_CIPHER-NULL — the NULL EVP_CIPHER implementation, no cap 🫶

🌸 DESCRIPTION 🌸

So this is the support for a NULL symmetric encryption using the EVP_CIPHER API. It's what gets used when the TLS cipher suite is TLS_NULL_WITH_NULL_NULL — and the way that this works is honestly iconic in its laziness: it does no encryption (just copies the data 💀) and has a mac size of zero.

No thoughts, head empty, just vibing and copying bytes. We love a low-effort queen 👑

🦋 Algorithm Name 🦋

The following algorithm is available in the default provider:

  • "NULL"

That's it. One name. One vibe. Main character energy fr fr 🌈

💜 Parameters 💜

This implementation supports the following parameters:

Gettable EVP_CIPHER parameters

See "Gettable EVP_CIPHER parameters" in EVP_EncryptInit(3) — go read that if you wanna know the tea ☕

Gettable EVP_CIPHER_CTX parameters

  • "keylen" (OSSL_CIPHER_PARAM_KEYLEN) <unsigned integer>
  • "ivlen" (OSSL_CIPHER_PARAM_IVLEN and <OSSL_CIPHER_PARAM_AEAD_IVLEN) <unsigned integer>
  • "tls-mac" (OSSL_CIPHER_PARAM_TLS_MAC) <octet ptr>

See "PARAMETERS" in EVP_EncryptInit(3) for further information — bestie, that's where the lore lives 📖

Settable EVP_CIPHER_CTX parameters

  • "tls-mac-size" (OSSL_CIPHER_PARAM_TLS_MAC_SIZE) <unsigned integer>

See "PARAMETERS" in EVP_EncryptInit(3) for further information. Same vibe, different direction 💫

🧚 CONFORMING TO 🧚

RFC 5246 section-6.2.3.1 — yes, it's a real spec, not me making stuff up 🔥

👑 SEE ALSO 👑

Go give 'em a read, they're giving supporting cast excellence 🌟

Copyright 2023 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>.

💀 real talk: the NULL cipher does zero encryption and zero MAC, so like… it's literally a fancy memcpy. Don't go thinking it's protecting anything, bestie. It's here for TLS_NULL_WITH_NULL_NULL and that's it. The spec is RFC 5246 section-6.2.3.1 and the details above are the whole story 💅

That's the whole page, bestie — stay slay, keep your ciphers real (this one isn't, and that's the point 😭). This was EVP_CIPHER-NULL(7ossl) from OpenSSL version 3.5.9, dated 2026-09-29 — mwah, periodt! 💖🦋✨

📦 where this page comes from