Bluetooth: Add function to derive AMP key using hmac

hmac(sha256) will be used for AMP key generation.

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
This commit is contained in:
Dmitry Kasatkin 2012-09-27 17:26:17 +03:00 committed by Gustavo Padovan
parent 93c3e8f5c9
commit ba221bbaba

View File

@ -16,6 +16,7 @@
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/a2mp.h>
#include <net/bluetooth/amp.h>
#include <crypto/hash.h>
/* Remote AMP Controllers interface */
static void amp_ctrl_get(struct amp_ctrl *ctrl)
@ -125,6 +126,41 @@ struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr,
return hcon;
}
/* AMP crypto key generation interface */
static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output)
{
int ret = 0;
struct crypto_shash *tfm;
if (!ksize)
return -EINVAL;
tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
if (IS_ERR(tfm)) {
BT_DBG("crypto_alloc_ahash failed: err %ld", PTR_ERR(tfm));
return PTR_ERR(tfm);
}
ret = crypto_shash_setkey(tfm, key, ksize);
if (ret) {
BT_DBG("crypto_ahash_setkey failed: err %d", ret);
} else {
struct {
struct shash_desc shash;
char ctx[crypto_shash_descsize(tfm)];
} desc;
desc.shash.tfm = tfm;
desc.shash.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
ret = crypto_shash_digest(&desc.shash, plaintext, psize,
output);
}
crypto_free_shash(tfm);
return ret;
}
void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle)
{
struct hci_cp_read_local_amp_assoc cp;