[PATCH 16/33] crypto: aes - Remove AES-CBC-MAC support

From: Eric Biggers

Date: Tue Jul 07 2026 - 01:39:55 EST


"cbcmac(aes)" is used only by the "ccm" template when instantiated as
"ccm(aes)". Since native "ccm(aes)" support has been added to
crypto/aes.c, the "cbcmac(aes)" crypto_shash is no longer needed.

Note that "cmac(aes)" and "xcbc(aes)" remain supported.

Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/Kconfig | 4 +-
crypto/aes.c | 62 ----------------------------
crypto/testmgr.c | 6 +--
drivers/crypto/starfive/jh7110-aes.c | 2 +-
4 files changed, 6 insertions(+), 68 deletions(-)

diff --git a/crypto/Kconfig b/crypto/Kconfig
index e6b894dc784a..83adbd54d725 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -359,14 +359,14 @@ config CRYPTO_AES
select CRYPTO_ALGAPI
select CRYPTO_LIB_AES
select CRYPTO_LIB_AES_CBC if CRYPTO_CBC || CRYPTO_CTS
- select CRYPTO_LIB_AES_CBC_MACS if CRYPTO_CMAC || CRYPTO_XCBC || CRYPTO_CCM
+ select CRYPTO_LIB_AES_CBC_MACS if CRYPTO_CMAC || CRYPTO_XCBC
select CRYPTO_LIB_AES_CCM if CRYPTO_CCM
select CRYPTO_LIB_AES_CTR if CRYPTO_CTR || CRYPTO_XCTR
select CRYPTO_LIB_AES_ECB if CRYPTO_ECB
select CRYPTO_LIB_AES_GCM if CRYPTO_GCM
select CRYPTO_LIB_AES_XTS if CRYPTO_XTS
select CRYPTO_AEAD if CRYPTO_GCM || CRYPTO_CCM
- select CRYPTO_HASH if CRYPTO_CMAC || CRYPTO_XCBC || CRYPTO_CCM
+ select CRYPTO_HASH if CRYPTO_CMAC || CRYPTO_XCBC
# CRYPTO_SKCIPHER should be selected only if a mode that needs it is
# enabled, but that doesn't work due to a recursive dependency caused by
# CRYPTO_SKCIPHER selecting CRYPTO_ECB. So just always select it.
diff --git a/crypto/aes.c b/crypto/aes.c
index ac5190292b3c..5f9c8eab67b4 100644
--- a/crypto/aes.c
+++ b/crypto/aes.c
@@ -95,47 +95,6 @@ static int __maybe_unused crypto_aes_cmac_digest(struct shash_desc *desc,
return 0;
}

-#define AES_CBCMAC_KEY(tfm) ((struct aes_enckey *)crypto_shash_ctx(tfm))
-#define AES_CBCMAC_CTX(desc) ((struct aes_cbcmac_ctx *)shash_desc_ctx(desc))
-
-static int __maybe_unused crypto_aes_cbcmac_setkey(struct crypto_shash *tfm,
- const u8 *in_key,
- unsigned int key_len)
-{
- return aes_prepareenckey(AES_CBCMAC_KEY(tfm), in_key, key_len);
-}
-
-static int __maybe_unused crypto_aes_cbcmac_init(struct shash_desc *desc)
-{
- aes_cbcmac_init(AES_CBCMAC_CTX(desc), AES_CBCMAC_KEY(desc->tfm));
- return 0;
-}
-
-static int __maybe_unused crypto_aes_cbcmac_update(struct shash_desc *desc,
- const u8 *data,
- unsigned int len)
-{
- aes_cbcmac_update(AES_CBCMAC_CTX(desc), data, len);
- return 0;
-}
-
-static int __maybe_unused crypto_aes_cbcmac_final(struct shash_desc *desc,
- u8 *out)
-{
- aes_cbcmac_final(AES_CBCMAC_CTX(desc), out);
- return 0;
-}
-
-static int __maybe_unused crypto_aes_cbcmac_digest(struct shash_desc *desc,
- const u8 *data,
- unsigned int len, u8 *out)
-{
- aes_cbcmac_init(AES_CBCMAC_CTX(desc), AES_CBCMAC_KEY(desc->tfm));
- aes_cbcmac_update(AES_CBCMAC_CTX(desc), data, len);
- aes_cbcmac_final(AES_CBCMAC_CTX(desc), out);
- return 0;
-}
-
static struct crypto_alg alg = {
.cra_name = "aes",
.cra_driver_name = "aes-lib",
@@ -190,23 +149,6 @@ static struct shash_alg mac_algs[] = {
.descsize = sizeof(struct aes_cmac_ctx),
},
#endif
-#if IS_ENABLED(CONFIG_CRYPTO_CCM)
- {
- .base.cra_name = "cbcmac(aes)",
- .base.cra_driver_name = "cbcmac-aes-lib",
- .base.cra_priority = 300,
- .base.cra_blocksize = AES_BLOCK_SIZE,
- .base.cra_ctxsize = sizeof(struct aes_enckey),
- .base.cra_module = THIS_MODULE,
- .digestsize = AES_BLOCK_SIZE,
- .setkey = crypto_aes_cbcmac_setkey,
- .init = crypto_aes_cbcmac_init,
- .update = crypto_aes_cbcmac_update,
- .final = crypto_aes_cbcmac_final,
- .digest = crypto_aes_cbcmac_digest,
- .descsize = sizeof(struct aes_cbcmac_ctx),
- },
-#endif
};

static __maybe_unused int
@@ -1096,10 +1038,6 @@ MODULE_ALIAS_CRYPTO("cmac-aes-lib");
MODULE_ALIAS_CRYPTO("xcbc(aes)");
MODULE_ALIAS_CRYPTO("xcbc-aes-lib");
#endif
-#if IS_ENABLED(CONFIG_CRYPTO_CCM)
-MODULE_ALIAS_CRYPTO("cbcmac(aes)");
-MODULE_ALIAS_CRYPTO("cbcmac-aes-lib");
-#endif
#if IS_ENABLED(CONFIG_CRYPTO_ECB)
MODULE_ALIAS_CRYPTO("ecb(aes)");
MODULE_ALIAS_CRYPTO("ecb-aes-lib");
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 4958211fbfa9..b25c15173c76 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -4421,7 +4421,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}, {
#endif
.alg = "cbcmac(aes)",
- .generic_driver = "cbcmac-aes-lib",
+ .generic_driver = "cbcmac(aes-lib)",
.test = alg_test_hash,
.suite = {
.hash = __VECS(aes_cbcmac_tv_template)
@@ -4434,7 +4434,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}, {
.alg = "ccm(aes)",
- .generic_driver = "ccm_base(ctr(aes-lib),cbcmac-aes-lib)",
+ .generic_driver = "ccm_base(ctr(aes-lib),cbcmac(aes-lib))",
.test = alg_test_aead,
.fips_allowed = 1,
.suite = {
@@ -5239,7 +5239,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}, {
.alg = "rfc4309(ccm(aes))",
- .generic_driver = "rfc4309(ccm_base(ctr(aes-lib),cbcmac-aes-lib))",
+ .generic_driver = "rfc4309(ccm_base(ctr(aes-lib),cbcmac(aes-lib)))",
.test = alg_test_aead,
.fips_allowed = 1,
.suite = {
diff --git a/drivers/crypto/starfive/jh7110-aes.c b/drivers/crypto/starfive/jh7110-aes.c
index a0713aa21250..c591a850f093 100644
--- a/drivers/crypto/starfive/jh7110-aes.c
+++ b/drivers/crypto/starfive/jh7110-aes.c
@@ -1003,7 +1003,7 @@ static int starfive_aes_ctr_init_tfm(struct crypto_skcipher *tfm)

static int starfive_aes_ccm_init_tfm(struct crypto_aead *tfm)
{
- return starfive_aes_aead_init_tfm(tfm, "ccm_base(ctr(aes-lib),cbcmac-aes-lib)");
+ return starfive_aes_aead_init_tfm(tfm, "ccm_base(ctr(aes-lib),cbcmac(aes-lib))");
}

static int starfive_aes_gcm_init_tfm(struct crypto_aead *tfm)
--
2.54.0