sha1_update(9)

🎀 NAME 🎀

sha1_update — update a SHA-1 context with message data 💅

okay so welcome to the Kernel API Manual page for sha1_update(9), bestie. This is literally the function that updates your SHA-1 context with message data, and we're gonna make it make sense ✨

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✨ SYNOPSIS ✨

the signature, no cap:

void sha1_update (struct sha1_ctx *ctx , const u8 *data , size_t len );

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🦋 ARGUMENTS 🦋

• ctx — the context to update; it must have been initialized (fr fr, do not skip this) 💖
• data — the message data 🎀
• len — the data length in bytes 🦋

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🌸 DESCRIPTION 🌸

okay so the whole description is short and iconic: this can be called any number of times. that's the tea. no cap, no secret extra rules — just call it as many times as you need and it does its update thing. periodt 🫶

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💅 CONTEXT 💅

Any context. That's it — literally any context, bestie. vibe check passed 💅

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🔥 SEE ALSO 🔥

Kernel file ./include/crypto/sha1.h and the whole SHA-1 + hmac_sha1 friend group:

• struct sha1_ctx(9)
• sha1_init(9)
• sha1_final(9)
• sha1(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)

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cute sign-off: this lil page lives under ./include/crypto, dated October 2026, and it's the sha1_update(9) page — mwah, slay, bye bestie 💋✨