mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-11-01 17:08:10 +00:00
026a733e66
SP800-108 defines three KDFs - this patch provides the counter KDF implementation. The KDF is implemented as a service function where the caller has to maintain the hash / HMAC state. Apart from this hash/HMAC state, no additional state is required to be maintained by either the caller or the KDF implementation. The key for the KDF is set with the crypto_kdf108_setkey function which is intended to be invoked before the caller requests a key derivation operation via crypto_kdf108_ctr_generate. SP800-108 allows the use of either a HMAC or a hash as crypto primitive for the KDF. When a HMAC primtive is intended to be used, crypto_kdf108_setkey must be used to set the HMAC key. Otherwise, for a hash crypto primitve crypto_kdf108_ctr_generate can be used immediately after allocating the hash handle. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
153 lines
3.6 KiB
C
153 lines
3.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
/*
|
|
* SP800-108 Key-derivation function
|
|
*
|
|
* Copyright (C) 2021, Stephan Mueller <smueller@chronox.de>
|
|
*/
|
|
|
|
#include <linux/fips.h>
|
|
#include <linux/module.h>
|
|
#include <crypto/kdf_sp800108.h>
|
|
#include <crypto/internal/kdf_selftest.h>
|
|
|
|
/*
|
|
* SP800-108 CTR KDF implementation
|
|
*/
|
|
int crypto_kdf108_ctr_generate(struct crypto_shash *kmd,
|
|
const struct kvec *info, unsigned int info_nvec,
|
|
u8 *dst, unsigned int dlen)
|
|
{
|
|
SHASH_DESC_ON_STACK(desc, kmd);
|
|
__be32 counter = cpu_to_be32(1);
|
|
const unsigned int h = crypto_shash_digestsize(kmd), dlen_orig = dlen;
|
|
unsigned int i;
|
|
int err = 0;
|
|
u8 *dst_orig = dst;
|
|
|
|
desc->tfm = kmd;
|
|
|
|
while (dlen) {
|
|
err = crypto_shash_init(desc);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = crypto_shash_update(desc, (u8 *)&counter, sizeof(__be32));
|
|
if (err)
|
|
goto out;
|
|
|
|
for (i = 0; i < info_nvec; i++) {
|
|
err = crypto_shash_update(desc, info[i].iov_base,
|
|
info[i].iov_len);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
if (dlen < h) {
|
|
u8 tmpbuffer[HASH_MAX_DIGESTSIZE];
|
|
|
|
err = crypto_shash_final(desc, tmpbuffer);
|
|
if (err)
|
|
goto out;
|
|
memcpy(dst, tmpbuffer, dlen);
|
|
memzero_explicit(tmpbuffer, h);
|
|
goto out;
|
|
}
|
|
|
|
err = crypto_shash_final(desc, dst);
|
|
if (err)
|
|
goto out;
|
|
|
|
dlen -= h;
|
|
dst += h;
|
|
counter = cpu_to_be32(be32_to_cpu(counter) + 1);
|
|
}
|
|
|
|
out:
|
|
if (err)
|
|
memzero_explicit(dst_orig, dlen_orig);
|
|
shash_desc_zero(desc);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(crypto_kdf108_ctr_generate);
|
|
|
|
/*
|
|
* The seeding of the KDF
|
|
*/
|
|
int crypto_kdf108_setkey(struct crypto_shash *kmd,
|
|
const u8 *key, size_t keylen,
|
|
const u8 *ikm, size_t ikmlen)
|
|
{
|
|
unsigned int ds = crypto_shash_digestsize(kmd);
|
|
|
|
/* SP800-108 does not support IKM */
|
|
if (ikm || ikmlen)
|
|
return -EINVAL;
|
|
|
|
/* Check according to SP800-108 section 7.2 */
|
|
if (ds > keylen)
|
|
return -EINVAL;
|
|
|
|
/* Set the key for the MAC used for the KDF. */
|
|
return crypto_shash_setkey(kmd, key, keylen);
|
|
}
|
|
EXPORT_SYMBOL(crypto_kdf108_setkey);
|
|
|
|
/*
|
|
* Test vector obtained from
|
|
* http://csrc.nist.gov/groups/STM/cavp/documents/KBKDF800-108/CounterMode.zip
|
|
*/
|
|
static const struct kdf_testvec kdf_ctr_hmac_sha256_tv_template[] = {
|
|
{
|
|
.key = "\xdd\x1d\x91\xb7\xd9\x0b\x2b\xd3"
|
|
"\x13\x85\x33\xce\x92\xb2\x72\xfb"
|
|
"\xf8\xa3\x69\x31\x6a\xef\xe2\x42"
|
|
"\xe6\x59\xcc\x0a\xe2\x38\xaf\xe0",
|
|
.keylen = 32,
|
|
.ikm = NULL,
|
|
.ikmlen = 0,
|
|
.info = {
|
|
.iov_base = "\x01\x32\x2b\x96\xb3\x0a\xcd\x19"
|
|
"\x79\x79\x44\x4e\x46\x8e\x1c\x5c"
|
|
"\x68\x59\xbf\x1b\x1c\xf9\x51\xb7"
|
|
"\xe7\x25\x30\x3e\x23\x7e\x46\xb8"
|
|
"\x64\xa1\x45\xfa\xb2\x5e\x51\x7b"
|
|
"\x08\xf8\x68\x3d\x03\x15\xbb\x29"
|
|
"\x11\xd8\x0a\x0e\x8a\xba\x17\xf3"
|
|
"\xb4\x13\xfa\xac",
|
|
.iov_len = 60
|
|
},
|
|
.expected = "\x10\x62\x13\x42\xbf\xb0\xfd\x40"
|
|
"\x04\x6c\x0e\x29\xf2\xcf\xdb\xf0",
|
|
.expectedlen = 16
|
|
}
|
|
};
|
|
|
|
static int __init crypto_kdf108_init(void)
|
|
{
|
|
int ret = kdf_test(&kdf_ctr_hmac_sha256_tv_template[0], "hmac(sha256)",
|
|
crypto_kdf108_setkey, crypto_kdf108_ctr_generate);
|
|
|
|
if (ret) {
|
|
if (fips_enabled)
|
|
panic("alg: self-tests for CTR-KDF (hmac(sha256)) failed (rc=%d)\n",
|
|
ret);
|
|
|
|
WARN(1,
|
|
"alg: self-tests for CTR-KDF (hmac(sha256)) failed (rc=%d)\n",
|
|
ret);
|
|
} else {
|
|
pr_info("alg: self-tests for CTR-KDF (hmac(sha256)) passed\n");
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void __exit crypto_kdf108_exit(void) { }
|
|
|
|
module_init(crypto_kdf108_init);
|
|
module_exit(crypto_kdf108_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
|
|
MODULE_DESCRIPTION("Key Derivation Function conformant to SP800-108");
|