ubifs_hash_calc_hmac(9)

💖 ubifs_hash_calc_hmac(9) 💖

Okay bestie, so this one is from the Kernel API Manual and it's lowkey a little legend: ubifs_hash_calc_hmac — the function whose whole personality is calculate a HMAC from a hash. That's it, that's the vibe. 🎀

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✨ SYNOPSIS ✨

int ubifs_hash_calc_hmac (const struct ubifs_info *c , const u8 *hash ,
u8 *hmac );

Like, look at her. Three args, one int coming back. Iconic signature, no notes. 👑

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🌸 ARGUMENTS 🌸

• c — the UBIFS file-system description object, aka the main character handing over all the context 💅
• hash — the node we're calculating a HMAC for. That's the assignment, that's the task 🫶
• hmac — the returned HMAC, i.e. where the answer gets dropped off on the way out ✨

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🦋 DESCRIPTION 🦋

So what does she return? Literally this:

Returns 0 for success or a negative error code otherwise.

That's the whole description, bestie. 0 = slay, negative = not slay 😭. No cap, that's genuinely all she wrote.

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💜 SEE ALSO 💜

The kernel file is ./fs/ubifs/auth.c and honestly the whole friend group shows up here — no gatekeeping, everyone's invited:

• __ubifs_node_calc_hash(9)
• ubifs_prepare_auth_node(9)
• __ubifs_hash_get_desc(9)
• ubifs_bad_hash(9)
• __ubifs_node_check_hash(9)
• ubifs_sb_verify_signature(9)
• ubifs_init_authentication(9)
• __ubifs_exit_authentication(9)
• ubifs_node_calc_hmac(9)
• __ubifs_node_insert_hmac(9)
• __ubifs_node_verify_hmac(9)
• ubifs_hmac_wkm(9)

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And that's the whole page, bestie! 🧚 This lil masterpiece lives at ./fs/ubifs and it's dated October 2026 — yes, future girlie behavior, we love to see it. Periodt. 💀💖