Re: [PATCH 00/21] nvme-auth: use crypto library for HMAC and hashing

Ard Biesheuvel
2026-03-02T15:07:27Z

On Mon, 2 Mar 2026, at 08:59, Eric Biggers wrote:
> This series converts the implementation of NVMe in-band authentication
> to use the crypto library instead of crypto_shash for HMAC and hashing.
>
> The result is simpler, faster, and more reliable. Notably, it
> eliminates a lot of dynamic memory allocations, indirect calls, lookups
> in crypto_alg_list, and other API overhead. It also uses the library's
> support for initializing HMAC contexts directly from a raw key, which is
> an optimization not accessible via crypto_shash. Finally, a lot of the
> error handling code goes away, since the library functions just always
> succeed and return void.
>
> The last patch removes crypto/hkdf.c, as it's no longer needed.
>
> This series applies to v7.0-rc1 and is targeting the nvme tree.
>
> I've tested the TLS key derivation using the KUnit test suite added in
> this series. I don't know how to test the other parts, but it all
> should behave the same as before.
>
> Eric Biggers (21):
> nvme-auth: add NVME_AUTH_MAX_DIGEST_SIZE constant
> nvme-auth: common: constify static data
> nvme-auth: use proper argument types
> nvme-auth: common: add KUnit tests for TLS key derivation
> nvme-auth: rename nvme_auth_generate_key() to nvme_auth_parse_key()
> nvme-auth: common: explicitly verify psk_len == hash_len
> nvme-auth: common: add HMAC helper functions
> nvme-auth: common: use crypto library in nvme_auth_transform_key()
> nvme-auth: common: use crypto library in
> nvme_auth_augmented_challenge()
> nvme-auth: common: use crypto library in nvme_auth_generate_psk()
> nvme-auth: common: use crypto library in nvme_auth_generate_digest()
> nvme-auth: common: use crypto library in nvme_auth_derive_tls_psk()
> nvme-auth: host: use crypto library in
> nvme_auth_dhchap_setup_host_response()
> nvme-auth: host: use crypto library in
> nvme_auth_dhchap_setup_ctrl_response()
> nvme-auth: host: remove allocation of crypto_shash
> nvme-auth: target: remove obsolete crypto_has_shash() checks
> nvme-auth: target: use crypto library in nvmet_auth_host_hash()
> nvme-auth: target: use crypto library in nvmet_auth_ctrl_hash()
> nvme-auth: common: remove nvme_auth_digest_name()
> nvme-auth: common: remove selections of no-longer used crypto modules
> crypto: remove HKDF library
>

For the series,

Acked-by: Ard Biesheuvel <ardb@kernel.org>