EVP_IDEA_CBC(3SSL)

💖 EVP_IDEA_CBC 💖

okay bestie, welcome to EVP_IDEA_CBC(3SSL) — a lil slice of the OpenSSL manual, freshly served ✨

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🎀 NAME 🎀

EVP_idea_cbc, EVP_idea_cfb, EVP_idea_cfb64, EVP_idea_ecb, EVP_idea_ofb — it's giving EVP IDEA cipher, and honestly? iconic. 💅

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✨ 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);

five little functions, all serving cunt, all handing you back a const EVP_CIPHER * 🫶

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🌸 DESCRIPTION 🌸

so like. this is the IDEA encryption algorithm for EVP. that's the whole vibe. 🦋

Here's the lineup, one bullet each, no skips:

• EVP_idea_cbc(), EVP_idea_cfb(), EVP_idea_cfb64(), EVP_idea_ecb(), EVP_idea_ofb() — these give you the IDEA encryption algorithm in CBC, CFB, ECB and OFB modes respectively. yes, that's four modes across five functions, cfb64 is just cfb's extra-special sibling, we don't make the rules 💜

not me noticing there's no cfb128 here... anyway don't come for me, this is literally what the page says 🙈

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👑 NOTES 👑

bestie. listen. 👀

Developers should be aware of the negative performance implications of calling these functions multiple times — like, calling them over and over is not the move, it's giving lag 😭 — and should consider using EVP_CIPHER_fetch(3) with EVP_CIPHER-IDEA(7) instead. that's the glow-up route ✨

also, go read "Performance" in crypto(7) for further information, fr fr. 📚

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⭐ RETURN VALUES ⭐

These functions return an EVP_CIPHER structure that contains the implementation of the symmetric cipher. that's it, that's the whole return. no crumbs, just the struct 💖

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🌈 SEE ALSO 🌈

• evp(7)
• EVP_EncryptInit(3)

go read them, they're part of the lore 🧚

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💜 COPYRIGHT 💜

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>.

yes that's a real URL in the original, i'm not deleting it, the facts stay facts periodt 💅

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aaaand that's the whole page, bestie!! this was OpenSSL 4.0.3, dated 2026-09-29, and it slapped. no cap. 🌸🎀💖