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From:   Stephan =?ISO-8859-1?Q?M=FCller?= <smueller@chronox.de>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     linux-crypto@vger.kernel.org, Niolai Stange <nstange@suse.com>,
        Simo Sorce <simo@redhat.com>
Subject: [PATCH v2 2/2] crypto: HMAC - disallow keys < 112 bits in FIPS mode
Date:   Tue, 01 Feb 2022 09:41:32 +0100
Message-ID: <25394269.1r3eYUQgxm@positron.chronox.de>
In-Reply-To: <4609802.vXUDI8C0e8@positron.chronox.de>
References: <2075651.9o76ZdvQCi@positron.chronox.de> <YfN1HKqL9GT9R25Z@gondor.apana.org.au> <4609802.vXUDI8C0e8@positron.chronox.de>
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FIPS 140 requires a minimum security strength of 112 bits. This implies
that the HMAC key must not be smaller than 112 in FIPS mode.

This restriction implies that the test vectors for HMAC that have a key
that is smaller than 112 bits must be disabled when FIPS support is
compiled.

Signed-off-by: Stephan Mueller <smueller@chronox.de>
---
 crypto/hmac.c    | 4 ++++
 crypto/testmgr.h | 9 +++++++++
 2 files changed, 13 insertions(+)

diff --git a/crypto/hmac.c b/crypto/hmac.c
index 25856aa7ccbf..3610ff0b6739 100644
--- a/crypto/hmac.c
+++ b/crypto/hmac.c
@@ -15,6 +15,7 @@
 #include <crypto/internal/hash.h>
 #include <crypto/scatterwalk.h>
 #include <linux/err.h>
+#include <linux/fips.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -51,6 +52,9 @@ static int hmac_setkey(struct crypto_shash *parent,
 	SHASH_DESC_ON_STACK(shash, hash);
 	unsigned int i;
 
+	if (fips_enabled && (keylen < 112 / 8))
+		return -EINVAL;
+
 	shash->tfm = hash;
 
 	if (keylen > bs) {
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 17b37525f289..85ccf811f5e7 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -5715,6 +5715,7 @@ static const struct hash_testvec hmac_sha1_tv_template[] = {
 		.psize	= 28,
 		.digest	= "\xef\xfc\xdf\x6a\xe5\xeb\x2f\xa2\xd2\x74"
 			  "\x16\xd5\xf1\x84\xdf\x9c\x25\x9a\x7c\x79",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa",
 		.ksize	= 20,
@@ -5804,6 +5805,7 @@ static const struct hash_testvec hmac_sha224_tv_template[] = {
 			"\x45\x69\x0f\x3a\x7e\x9e\x6d\x0f"
 			"\x8b\xbe\xa2\xa3\x9e\x61\x48\x00"
 			"\x8f\xd0\x5e\x44",
+		.fips_skip = 1,
 	}, {
 		.key    = "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			"\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -5947,6 +5949,7 @@ static const struct hash_testvec hmac_sha256_tv_template[] = {
 			  "\x6a\x04\x24\x26\x08\x95\x75\xc7"
 			  "\x5a\x00\x3f\x08\x9d\x27\x39\x83"
 			  "\x9d\xec\x58\xb9\x64\xec\x38\x43",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			"\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6445,6 +6448,7 @@ static const struct hash_testvec hmac_sha384_tv_template[] = {
 			  "\xe4\x2e\xc3\x73\x63\x22\x44\x5e"
 			  "\x8e\x22\x40\xca\x5e\x69\xe2\xc7"
 			  "\x8b\x32\x39\xec\xfa\xb2\x16\x49",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6545,6 +6549,7 @@ static const struct hash_testvec hmac_sha512_tv_template[] = {
 			  "\x6d\x03\x4f\x65\xf8\xf0\xe6\xfd"
 			  "\xca\xea\xb1\xa3\x4d\x4a\x6b\x4b"
 			  "\x63\x6e\x07\x0a\x38\xbc\xe7\x37",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6640,6 +6645,7 @@ static const struct hash_testvec hmac_sha3_224_tv_template[] = {
 			  "\x1b\x79\x86\x34\xad\x38\x68\x11"
 			  "\xc2\xcf\xc8\x5b\xfa\xf5\xd5\x2b"
 			  "\xba\xce\x5e\x66",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6727,6 +6733,7 @@ static const struct hash_testvec hmac_sha3_256_tv_template[] = {
 			  "\x35\x96\xbb\xb0\xda\x73\xb8\x87"
 			  "\xc9\x17\x1f\x93\x09\x5b\x29\x4a"
 			  "\xe8\x57\xfb\xe2\x64\x5e\x1b\xa5",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6818,6 +6825,7 @@ static const struct hash_testvec hmac_sha3_384_tv_template[] = {
 			  "\x3c\xa1\x35\x08\xa9\x32\x43\xce"
 			  "\x48\xc0\x45\xdc\x00\x7f\x26\xa2"
 			  "\x1b\x3f\x5e\x0e\x9d\xf4\xc2\x0a",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
@@ -6917,6 +6925,7 @@ static const struct hash_testvec hmac_sha3_512_tv_template[] = {
 			  "\xee\x7a\x0c\x31\xd0\x22\xa9\x5e"
 			  "\x1f\xc9\x2b\xa9\xd7\x7d\xf8\x83"
 			  "\x96\x02\x75\xbe\xb4\xe6\x20\x24",
+		.fips_skip = 1,
 	}, {
 		.key	= "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
 			  "\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa"
-- 
2.33.1