__ubifs_node_insert_hmac(9)

💅 __ubifs_node_insert_hmac (9) — from the Kernel API Manual, bestie ✨

okay so picture this: it's giving kernel-crypto realness, and the main character is a function called __ubifs_node_insert_hmac. this whole page lives in the Kernel API Manual, and it's about smooshing a HMAC right into a UBIFS node. no cap, that's the whole vibe. 🦋

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🌸 NAME 🌸

__ubifs_node_insert_hmac — insert a HMAC into a UBIFS node 💅

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✨ SYNOPSIS ✨

int __ubifs_node_insert_hmac (const struct ubifs_info *c , void *node ,
int len , int ofs_hmac );

like, literally that's the signature. copy it exactly, don't @ me. 🎀

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🫶 ARGUMENTS 🫶

• c — the UBIFS file-system description object. your whole fs situation, basically. 👑
• node — the node you're inserting a HMAC into. this is the glow-up target, bestie.
• len — the length of the node. gotta know how big the thing is. 📏
• ofs_hmac — the offset in the node where the HMAC gets inserted. like, exactly where the sparkle goes. ✨

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💖 DESCRIPTION 💖

so the way this works: this function inserts a HMAC at offset ofs_hmac into the node given in node. that's it, that's the whole job. 🌈

and the tea on the return value? this function returns 0 for success, or a negative error code otherwise. so if you see a negative number, something went off and you should lowkey panic (jk, just handle the error). 😭

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🦋 SEE ALSO 🦋

Kernel file ./fs/ubifs/auth.c, plus the whole friend group:

• __ubifs_node_calc_hash(9)
• ubifs_hash_calc_hmac(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_verify_hmac(9)
• ubifs_hmac_wkm(9)

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okay that's the page, periodt 💜 from ./fs/ubifs, dated October 2026, and the manual name tag says __ubifs_node_insert_hmac(9) — slay, go forth and insert those HMACs responsibly bestie 🎀🔥