spum_digest_size(9)

💖 NAME 💖

spum_digest_size — bestie, this is the one that tells you how big of a hash digest you should expect the SPU to hand back to you ✨

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🦋 SYNOPSIS 🦋

u32 spum_digest_size (u32 alg_digest_size , enum hash_alg alg , enum
hash_type htype );

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🎀 ARGUMENTS 🎀

• alg_digest_size — the number of bytes in the final digest for the given algo, like, the actual final size fr fr 🍓
• alg — the hash algorithm itself 👑
• htype — what kind of hash operation we're doing (init, update, full, etc.) — it's giving "which phase of the vibe are we in" 💅

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🌸 DESCRIPTION 🌸

Okay so picture this: you're doing incremental hashing for an algorithm that has a truncated hash (e.g., SHA224), and here's the plot twist — the SPU returns the full digest instead. Why? So it can be fed back as a partial result for the next chunk 💫 literally main character energy.

No cap, that's the whole thing. The full digest comes back so the next chunk has something to work with. Periodt 🫶

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🌈 SEE ALSO 🌈

Kernel file ./drivers/crypto/bcm/spu.c — plus the whole friend group, iykyk:

• spum_ns2_ctx_max_payload(9)
• spum_nsp_ctx_max_payload(9)
• spum_response_hdr_len(9)
• spum_hash_pad_len(9)
• spum_gcm_ccm_pad_len(9)
• spum_assoc_resp_len(9)
• spum_aead_ivlen(9)
• spum_hash_type(9)
• spum_create_request(9)
• spum_cipher_req_init(9)
• spum_cipher_req_finish(9)
• spum_request_pad(9)
• spum_xts_tweak_in_payload(9)
• spum_tx_status_len(9)
• spum_rx_status_len(9)
• spum_status_process(9)
• spum_ccm_update_iv(9)
• spum_wordalign_padlen(9)

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Reminder bestie: the SPU gives you the full digest even when the algorithm's hash is truncated — that's the whole ~point~ of this function, don't forget it 💀💖

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That's the page! 💜 Shoutout to the ./drivers/crypto/bcm crew — this one's dated October 2026, and it's filed under the Kernel API Manual because we stay documented and we stay iconic 👑✨🎀