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

Eric Biggers
2026-03-02T08:01:34Z

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

crypto/Kconfig | 6 -
crypto/Makefile | 1 -
crypto/hkdf.c | 573 ------------------------
drivers/nvme/common/.kunitconfig | 6 +
drivers/nvme/common/Kconfig | 14 +-
drivers/nvme/common/Makefile | 2 +
drivers/nvme/common/auth.c | 587 ++++++++++---------------
drivers/nvme/common/tests/auth_kunit.c | 175 ++++++++
drivers/nvme/host/auth.c | 160 +++----
drivers/nvme/host/sysfs.c | 4 +-
drivers/nvme/target/auth.c | 198 +++------
drivers/nvme/target/configfs.c | 3 -
drivers/nvme/target/fabrics-cmd-auth.c | 4 +-
drivers/nvme/target/nvmet.h | 2 +-
include/crypto/hkdf.h | 20 -
include/linux/nvme-auth.h | 41 +-
include/linux/nvme.h | 5 +
17 files changed, 571 insertions(+), 1230 deletions(-)
delete mode 100644 crypto/hkdf.c
create mode 100644 drivers/nvme/common/.kunitconfig
create mode 100644 drivers/nvme/common/tests/auth_kunit.c
delete mode 100644 include/crypto/hkdf.h

base-commit: 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f
--
2.53.0