s390/crypto: Extend key length check for AES-XTS in fips mode.

In fips mode only xts keys with 128 bit or 125 bit are allowed.
This fix extends the xts_aes_set_key function to check for these
valid key lengths in fips mode.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Harald Freudenberger 2016-12-15 14:58:08 +01:00 committed by Martin Schwidefsky
parent f3d3584faf
commit a4f2779ecf

View File

@ -28,6 +28,7 @@
#include <linux/cpufeature.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/fips.h>
#include <crypto/xts.h>
#include <asm/cpacf.h>
@ -501,6 +502,12 @@ static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
if (err)
return err;
/* In fips mode only 128 bit or 256 bit keys are valid */
if (fips_enabled && key_len != 32 && key_len != 64) {
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
/* Pick the correct function code based on the key length */
fc = (key_len == 32) ? CPACF_KM_XTS_128 :
(key_len == 64) ? CPACF_KM_XTS_256 : 0;