sha1(9)

💅 sha1(9)

okay so bestie, this one's from the Kernel API Manual — yes we're in kernel land now, put your hair up 🎀

✨ NAME ✨

sha1 — compute a SHA-1 message digest in one shot. like, all at once, no drip-feeding it data. one call, one digest, done. slay 💅

✨ SYNOPSIS ✨

void sha1 (const u8 *data , size_t len , u8 out[static SHA1_DIGEST_SIZE]
);

✨ ARGUMENTS ✨

• data — the message data. literally the thing you want hashed 🫶
• len — how long that data is, in bytes. yes bytes, not vibes ✨
• out — (output!) the resulting SHA-1 message digest goes in here. this is where the magic lands, so don't forget to pass it 👑

✨ CONTEXT ✨

Any context. fr fr — no locks, no sleep restrictions, nothing to worry about. go off whenever 🌈

✨ SEE ALSO ✨

Kernel file ./include/crypto/sha1.h, plus the whole sha1/hmac squad:

• struct sha1_ctx(9)
• sha1_init(9)
• sha1_update(9)
• sha1_final(9)
• struct hmac_sha1_key(9)
• struct hmac_sha1_ctx(9)
• hmac_sha1_preparekey(9)
• hmac_sha1_init(9)
• hmac_sha1_init_usingrawkey(9)
• hmac_sha1_update(9)
• hmac_sha1_final(9)
• hmac_sha1(9)
• hmac_sha1_usingrawkey(9)

bestie reminder: out is an output param — it needs to be able to hold SHA1_DIGEST_SIZE bytes, and that signature is not playing around about it 🫶

okay that's the whole page, go hash something iconic 💖

—

mwah, this page lives in ./include/crypto, and it's stamped October 2026 in the sha1(9) era. catch you in the next manpage, love u, bye 🦋🌸