RSA_BLINDING_ON(3SSL)

📦
version 4.0.3 · 14 versions
, in ubuntu stonking

💖 RSA_BLINDING_ON 💖

okay bestie, welcome to RSA_BLINDING_ON(3SSL) — this is one of the OpenSSL man pages, and it's all about protecting your RSA operations from timing attacks 🕵️♀️✨

✨ NAME ✨

RSA_blinding_on, RSA_blinding_off — protect the RSA operation from timing attacks 💅

🌸 SYNOPSIS 🌸

#include <openssl/rsa.h>

so like… heads up before you get attached: the following functions have been deprecated since OpenSSL 3.0 😭 and you can hide them entirely by defining OPENSSL_API_COMPAT with a suitable version value — go check openssl_user_macros(7) for the deets, it's literally the sibling page for this:

int RSA_blinding_on(RSA *rsa, BN_CTX *ctx);

void RSA_blinding_off(RSA *rsa);

🦋 DESCRIPTION 🦋

fr fr, every single function on this page is deprecated. all of them. yes, even the one you were about to use. 😭

okay so here's the tea: RSA is vulnerable to timing attacks. if a hater can measure how long your RSA decryption or signature operations take, they can start piecing things together. so in any setup like that, blinding must be used to protect the RSA operation from that attack. no cap. 🔥

RSA_blinding_on() turns blinding on for key rsa and generates a random blinding factor. the ctx there is either NULL or a preallocated and initialized BN_CTX. 🎀

RSA_blinding_off() turns blinding off and frees the memory used for the blinding factor. bye bye memory, it was giving ✨ responsible resource management ✨.

👑 RETURN VALUES 👑

  • RSA_blinding_on() returns 1 on success, and 0 if an error occurred. slay or flop, no in-between 💀
  • RSA_blinding_off() returns no value. it's a void function, it simply does its little job and leaves.

🎀 HISTORY 🎀

the way that all of these functions were deprecated in OpenSSL 3.0… iconic but bittersweet 💔

Copyright 2000-2021 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>.

bestie reminder: deprecated ≠ deleted, but it does mean the vibes have shifted. if you're writing new code, go find the non-deprecated path. this page is lore now 📜

and that's the whole page, mwah 💋 this was version 4.0.3, dated 2026-09-29 — from the OpenSSL era of the manual, RSA_BLINDING_ON(3SSL), periodt. 🧚‍♀️⭐

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