mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-16 04:21:09 -04:00
Code Issues Packages Projects Releases Wiki Activity

lib/crypto: aes: Add FIPS self-test for CMAC

Browse Source 
Add a FIPS cryptographic algorithm self-test for AES-CMAC to fulfill the
self-test requirement when this code is built into a FIPS 140
cryptographic module.  This provides parity with the traditional crypto
API, which uses crypto/testmgr.c to meet the FIPS self-test requirement.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20260218213501.136844-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
This commit is contained in:
Eric Biggers
2026-02-18 13:34:53 -08:00
parent a348fd1f6e
commit 2505f9157e
3 changed files with 47 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

35
lib/crypto/aes.c
View File

@@ -12,6 +12,7 @@
#include <linux/export.h>
#include <linux/module.h>
#include <linux/unaligned.h>
#include "fips.h"
static const u8 ____cacheline_aligned aes_sbox[] = {
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
@@ -708,12 +709,41 @@ void aes_cbcmac_final(struct aes_cbcmac_ctx *ctx, u8 out[AES_BLOCK_SIZE])
memzero_explicit(ctx, sizeof(*ctx));
}
EXPORT_SYMBOL_NS_GPL(aes_cbcmac_final, "CRYPTO_INTERNAL");
#endif /* CONFIG_CRYPTO_LIB_AES_CBC_MACS */
#ifdef aes_mod_init_arch
/*
* FIPS cryptographic algorithm self-test for AES-CMAC. As per the FIPS 140-3
* Implementation Guidance, a cryptographic algorithm self-test for at least one
* of AES-GCM, AES-CCM, AES-CMAC, or AES-GMAC is required if any of those modes
* is implemented. This fulfills that requirement via AES-CMAC.
*
* This is just for FIPS. The full tests are in the KUnit test suite.
*/
static void __init aes_cmac_fips_test(void)
{
struct aes_cmac_key key;
u8 mac[AES_BLOCK_SIZE];
if (aes_cmac_preparekey(&key, fips_test_key, sizeof(fips_test_key)) !=
0)
panic("aes: CMAC FIPS self-test failed (preparekey)\n");
aes_cmac(&key, fips_test_data, sizeof(fips_test_data), mac);
if (memcmp(fips_test_aes_cmac_value, mac, sizeof(mac)) != 0)
panic("aes: CMAC FIPS self-test failed (wrong MAC)\n");
memzero_explicit(&key, sizeof(key));
}
#else /* CONFIG_CRYPTO_LIB_AES_CBC_MACS */
static inline void aes_cmac_fips_test(void)
{
}
#endif /* !CONFIG_CRYPTO_LIB_AES_CBC_MACS */
static int __init aes_mod_init(void)
{
#ifdef aes_mod_init_arch
aes_mod_init_arch();
#endif
if (fips_enabled)
aes_cmac_fips_test();
return 0;
}
subsys_initcall(aes_mod_init);
@@ -722,7 +752,6 @@ static void __exit aes_mod_exit(void)
{
}
module_exit(aes_mod_exit);
#endif
MODULE_DESCRIPTION("AES block cipher");
MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");

5
lib/crypto/fips.h
View File

@@ -43,3 +43,8 @@ static const u8 fips_test_sha3_256_value[] __initconst __maybe_unused = {
0xba, 0x9b, 0xb6, 0xaa, 0x32, 0xa7, 0x97, 0x00,
0x98, 0xdb, 0xff, 0xe7, 0xc6, 0xde, 0xb5, 0x82,
};
static const u8 fips_test_aes_cmac_value[] __initconst __maybe_unused = {
0xc5, 0x88, 0x28, 0x55, 0xd7, 0x2c, 0x00, 0xb6,
0x6a, 0xa7, 0xfc, 0x82, 0x90, 0x81, 0xcf, 0x18,
};

10
scripts/crypto/gen-fips-testvecs.py
View File

@@ -3,8 +3,12 @@
#
# Script that generates lib/crypto/fips.h
#
# Requires that python-cryptography be installed.
#
# Copyright 2025 Google LLC
import cryptography.hazmat.primitives.ciphers
import cryptography.hazmat.primitives.cmac
import hashlib
import hmac
@@ -34,3 +38,9 @@ for alg in 'sha1', 'sha256', 'sha512':
print_static_u8_array_definition(f'fips_test_sha3_256_value',
hashlib.sha3_256(fips_test_data).digest())
aes = cryptography.hazmat.primitives.ciphers.algorithms.AES(fips_test_key)
aes_cmac = cryptography.hazmat.primitives.cmac.CMAC(aes)
aes_cmac.update(fips_test_data)
print_static_u8_array_definition('fips_test_aes_cmac_value',
aes_cmac.finalize())