spu2_fmd_ctrl1_write(9)

💅 spu2_fmd_ctrl1_write(9) 💅

okay bestie, welcome to the Kernel API Manual ✨ this page is literally all about writing the ctrl1 field in the fixed metadata (FMD) field of an SPU request packet. no cap 🫶

🌸 NAME 🌸

spu2_fmd_ctrl1_write — write the ctrl1 field in the fixed metadata (FMD) field of an SPU request packet. 💖

✨ SYNOPSIS ✨

it's giving void return, and the full signature is right here:

void spu2_fmd_ctrl1_write (struct SPU2_FMD *fmd , bool is_inbound , u64
       assoc_size , u64 auth_key_len , u64 cipher_key_len , bool gen_iv , bool
       hash_iv , bool return_iv , u64 ret_iv_len , u64 ret_iv_offset , u64
       cipher_iv_len , u64 digest_size , bool return_payload , bool return_md
       );

🎀 ARGUMENTS 🎀

every single argument, in order, with all the details preserved — let's go 💅

• fmd — start of the FMD field to be written. 💖
• is_inbound — true if decrypting. false if encrypting. 🔐
• assoc_size — length of additional associated data, in bytes.
• auth_key_len — length of authentication key, in bytes.
• cipher_key_len — length of cipher key, in bytes.
• gen_iv — if true, hw generates IV and returns in response. ✨
• hash_iv — IV participates in hash. Used for IPSEC and TLS.
• return_iv — return IV in output packet before payload.
• ret_iv_len — length of IV returned from SPU, in bytes.
• ret_iv_offset — offset into full IV of start of returned IV.
• cipher_iv_len — length of input cipher IV, in bytes.
• digest_size — length of digest (aka, hash tag or ICV), in bytes.
• return_payload — return payload in SPU response.
• return_md — return metadata in SPU response.

🦋 DESCRIPTION 🦋

okay so real talk, bestie:

Packet can have AAD2 w/o AAD1. For algorithms currently supported, associated data goes in AAD2.

that's the whole vibe of this section, and every detail is staying exactly where it belongs. 💀✨

🌈 SEE ALSO 🌈

go read these, bestie — every reference from the original list is here:

• Kernel file — ./drivers/crypto/bcm/spu2.c
• spu2_cipher_xlate(9)
• spu2_hash_xlate(9)
• spu2_fmd_init(9)
• spu2_fmd_ctrl0_write(9)
• spu2_fmd_ctrl2_write(9)
• spu2_fmd_ctrl3_write(9)
• spu2_ctx_max_payload(9)
• spu2_payload_length(9)
• spu2_response_hdr_len(9)
• spu2_hash_pad_len(9)
• spu2_gcm_ccm_pad_len(9)
• spu2_assoc_resp_len(9)
• spu2_aead_ivlen(9)
• spu2_hash_type(9)
• spu2_digest_size(9)
• spu2_create_request(9)
• spu2_cipher_req_init(9)
• spu2_cipher_req_finish(9)
• spu2_request_pad(9)
• spu2_xts_tweak_in_payload(9)
• spu2_tx_status_len(9)
• spu2_rx_status_len(9)
• spu2_status_process(9)
• spu2_ccm_update_iv(9)
• spu2_wordalign_padlen(9)

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mwah 💋 this page is from source/version ./drivers/crypto/bcm and dated October 2026. periodt. 🎀