blk_crypto_init_key(9)

💅 blk_crypto_init_key (kernel API manual, bestie edition) 💅

Okay so real talk — this one's blk_crypto_init_key from the kernel API manual, and it's literally the glow-up your key needs before blk-crypto will even look at it. Let's get into it ✨

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🌸 NAME 🌸

blk_crypto_init_key — prepare a key for use with blk-crypto 🔑

Like, it takes your key and gets it all dressed up and ready for the blk-crypto ball. No cap.

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🎀 SYNOPSIS 🎀

int blk_crypto_init_key (struct blk_crypto_key *blk_key , const u8
*key_bytes , size_t key_size , enum blk_crypto_key_type key_type , enum
blk_crypto_mode_num crypto_mode , unsigned int dun_bytes , unsigned int
data_unit_size , int flags );

That's a lot of args, i know 😭 but every single one is doing its job, ok? Let's meet them 💖

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🦋 ARGUMENTS 🦋

• blk_key — pointer to the blk_crypto_key you're initializing. This is the main character here, the one getting set up 👑
• key_bytes — the actual bytes of the key. the raw material, the moment, the stuff 🍓
• key_size — size of the key in bytes. yes, in bytes, specifically 💅
• key_type — type of the key — either raw or hardware-wrapped. two vibes, you pick 🫶
• crypto_mode — identifier for the encryption algorithm to use. the algorithm's @ basically ✨
• dun_bytes — number of bytes that will be used to specify the DUN when this key is used. yes it's dun_bytes not "done bytes", i know, i giggled too 🙈
• data_unit_size — the data unit size to use for en/decryption. how big each unit is, lowkey important 🔥
• flags — BLK_CRYPTO_CFG_* flags. the little config sprinkles on top 🌈

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⭐ RETURN ⭐

0 on success, -errno on failure. that's it, that's the whole vibe check 💀

🚨 okay listen bestie, this part matters: the caller is responsible for zeroizing both blk_key and key_bytes when done with them. like, both of them. zeroize them. don't leave key material just lying around, that's genuinely not the move, fr fr 😤

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💜 SEE ALSO 💜

• Kernel file ./block/blk-crypto.c — the source, go read it, it's giving lore 📖
• blk_crypto_config_supported_natively(9)
• blk_crypto_start_using_key(9)
• blk_crypto_evict_key(9)

the whole friend group, honestly 🧚

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That's the whole page, bestie — slay, you now know how to prep a key for blk-crypto 💖✨ This one came out of ./block, dated October 2026, and it's page blk_crypto_init_key(9) of the kernel API manual. mwah, go zeroize your keys 🎀🦋💅