aes_ccm_preparekey(9)

📦 version 7.3.1, in nixpkgs unstable

💅 aes_ccm_preparekey(9) 💅

okay so bestie, this is a page from the Kernel API Manual and it's literally all about getting your AES-CCM key ready to slay ✨

🌸 NAME 🌸

aes_ccm_preparekey — prepare a key for AES-CCM encryption and decryption 🎀

✨ SYNOPSIS ✨

int aes_ccm_preparekey (struct aes_ccm_key *key , const u8 *in_key ,
size_t key_len , size_t authtag_len );

🫶 ARGUMENTS 🫶

  • key — (output) the key structure you're initializing, bestie. this is the glow-up destination 💖
  • in_key — the raw AES-CCM key. the actual key material, no filter 🦋
  • key_len — length of the raw key in bytes: 16, 24, or 32. pick one, those are the only valid ones 👑
  • authtag_len — length of the authentication tag in bytes: 4, 6, 8, 10, 12, 14, or 16. and like… 16 is recommended. fr fr, go with 16 💅

🌈 DESCRIPTION 🌈

okay so here's the vibe: you call this, it preps everything for AES-CCM encryption AND decryption. main character energy for your crypto setup 🔥

and listen — users should use memzero_explicit to zeroize the key struct at the end of its lifetime. literally do not skip this, it's the cleanup era and it matters 😭

tiny plot twist though: if this function fails, zeroization is unnecessary. so like, no pressure on the cleanup if it already flopped 🙈

🧚 CONTEXT 🧚

Any context. any. go off wherever you are ⭐

💜 RETURN 💜

  • 0 on success 🎉
  • -EINVAL if either of the lengths is invalid 💀 (you gave it a bad key_len or authtag_len, be so serious rn)

🦋 SEE ALSO 🦋

Kernel file ./include/crypto/aes-ccm.h and its whole friend group, iykyk:

okay that's the whole page, bestie 🍓 it lives in ./include/crypto and the version-on-record is October 2026 — go forth and prepare those keys, you're literally iconic for reading the docs 💖✨🎀

📦 where this page comes from