s390/crypto: Check des3_ede keys for uniqueness in fips mode

Triple-DES implementations will soon be required to check
for uniqueness of keys with fips mode enabled. Add checks
to ensure none of the 3 keys match.

Signed-off-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Matthew Rosato 2016-12-15 14:54:30 +01:00 committed by Martin Schwidefsky
parent 9437964885
commit f3d3584faf
1 changed files with 14 additions and 0 deletions

View File

@ -18,6 +18,7 @@
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <linux/crypto.h>
#include <linux/fips.h>
#include <crypto/algapi.h>
#include <crypto/des.h>
#include <asm/cpacf.h>
@ -221,6 +222,8 @@ static struct crypto_alg cbc_des_alg = {
* same as DES. Implementers MUST reject keys that exhibit this
* property.
*
* In fips mode additinally check for all 3 keys are unique.
*
*/
static int des3_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int key_len)
@ -234,6 +237,17 @@ static int des3_setkey(struct crypto_tfm *tfm, const u8 *key,
tfm->crt_flags |= CRYPTO_TFM_RES_WEAK_KEY;
return -EINVAL;
}
/* in fips mode, ensure k1 != k2 and k2 != k3 and k1 != k3 */
if (fips_enabled &&
!(crypto_memneq(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
crypto_memneq(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
DES_KEY_SIZE) &&
crypto_memneq(key, &key[DES_KEY_SIZE * 2], DES_KEY_SIZE))) {
tfm->crt_flags |= CRYPTO_TFM_RES_WEAK_KEY;
return -EINVAL;
}
memcpy(ctx->key, key, key_len);
return 0;
}