EVP_IDEA_CBC(3ossl)

📦 version 3.5.0, in opensuse-leap 16.0

🌸 EVP_IDEA_CBC — the OpenSSL manpage, but make it cute 🎀

okay so bestie, this is a page from OpenSSL (the 3ossl manual, iykyk) and it's literally all about the IDEA cipher as seen through EVP. it's short, it's sweet, it's giving "small but mighty" energy. let's get into it 💅

✨ NAME ✨

EVP_idea_cbc, EVP_idea_cfb, EVP_idea_cfb64, EVP_idea_ecb, EVP_idea_ofb — the EVP IDEA cipher. that's the whole vibe, no cap 🦋

💖 SYNOPSIS 💖

#include <openssl/evp.h>

const EVP_CIPHER *EVP_idea_cbc(void);
const EVP_CIPHER *EVP_idea_cfb(void);
const EVP_CIPHER *EVP_idea_cfb64(void);
const EVP_CIPHER *EVP_idea_ecb(void);
const EVP_CIPHER *EVP_idea_ofb(void);

look at them, all lined up, all returning a const EVP_CIPHER *, all taking void. iconic behavior honestly 👑

🦋 DESCRIPTION 🦋

so like, this whole page is about the IDEA encryption algorithm for EVP. that's it, that's the thesis 🫶

🌈 EVP_idea_cbc(), EVP_idea_cfb(), EVP_idea_cfb64(), EVP_idea_ecb(), EVP_idea_ofb()

these five besties give you the IDEA encryption algorithm in CBC, CFB, ECB and OFB modes respectively ✨

(and yes, both EVP_idea_cfb() and EVP_idea_cfb64() are CFB — they're listed together, don't come for me, that's just what the page says 💀)

👑 NOTES 👑

okay real talk for the devs out there, this is the part where you pay attention 📢

calling these functions multiple times has negative performance implications, and that's lowkey important. developers should be aware of that and should consider using EVP_CIPHER_fetch(3) with EVP_CIPHER-IDEA(7) instead 💡

want more details? peep "Performance" in crypto(7) — it's all there, fr fr.

💜 RETURN VALUES 💜

these functions return an EVP_CIPHER structure that contains the implementation of the symmetric cipher 🎀

want the full tea on what's actually inside an EVP_CIPHER structure? head over to EVP_CIPHER_meth_new(3) — that's where the details live, bestie 📖

⭐ SEE ALSO ⭐

Copyright 2017-2023 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>.

🫶 like, actually read the license, it's not just decorative, bestie.

and that's the whole page!! mwah 💋 this one's from OpenSSL 3.5.0, dated 2026-09-25, and it's the EVP_IDEA_CBC(3ossl) page — slay, go encrypt something (responsibly) 🔥🎀

📦 where this page comes from