tmp_suning_uos_patched/net/bluetooth/amp.c
Andrei Emeltchenko 5a34918669 Bluetooth: AMP: Add AMP key calculation
Function calculates AMP keys using hmac_sha256 helper. Calculated keys
are Generic AMP Link Key (gamp) and Dedicated AMP Link Key with
keyID "802b" for 802.11 PAL.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-09-27 17:30:22 -03:00

235 lines
5.4 KiB
C

/*
Copyright (c) 2011,2012 Intel Corp.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 and
only version 2 as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
*/
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci.h>
#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)
{
BT_DBG("ctrl %p orig refcnt %d", ctrl,
atomic_read(&ctrl->kref.refcount));
kref_get(&ctrl->kref);
}
static void amp_ctrl_destroy(struct kref *kref)
{
struct amp_ctrl *ctrl = container_of(kref, struct amp_ctrl, kref);
BT_DBG("ctrl %p", ctrl);
kfree(ctrl->assoc);
kfree(ctrl);
}
int amp_ctrl_put(struct amp_ctrl *ctrl)
{
BT_DBG("ctrl %p orig refcnt %d", ctrl,
atomic_read(&ctrl->kref.refcount));
return kref_put(&ctrl->kref, &amp_ctrl_destroy);
}
struct amp_ctrl *amp_ctrl_add(struct amp_mgr *mgr)
{
struct amp_ctrl *ctrl;
ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
if (!ctrl)
return NULL;
mutex_lock(&mgr->amp_ctrls_lock);
list_add(&ctrl->list, &mgr->amp_ctrls);
mutex_unlock(&mgr->amp_ctrls_lock);
kref_init(&ctrl->kref);
BT_DBG("mgr %p ctrl %p", mgr, ctrl);
return ctrl;
}
void amp_ctrl_list_flush(struct amp_mgr *mgr)
{
struct amp_ctrl *ctrl, *n;
BT_DBG("mgr %p", mgr);
mutex_lock(&mgr->amp_ctrls_lock);
list_for_each_entry_safe(ctrl, n, &mgr->amp_ctrls, list) {
list_del(&ctrl->list);
amp_ctrl_put(ctrl);
}
mutex_unlock(&mgr->amp_ctrls_lock);
}
struct amp_ctrl *amp_ctrl_lookup(struct amp_mgr *mgr, u8 id)
{
struct amp_ctrl *ctrl;
BT_DBG("mgr %p id %d", mgr, id);
mutex_lock(&mgr->amp_ctrls_lock);
list_for_each_entry(ctrl, &mgr->amp_ctrls, list) {
if (ctrl->id == id) {
amp_ctrl_get(ctrl);
mutex_unlock(&mgr->amp_ctrls_lock);
return ctrl;
}
}
mutex_unlock(&mgr->amp_ctrls_lock);
return NULL;
}
/* Physical Link interface */
static u8 __next_handle(struct amp_mgr *mgr)
{
if (++mgr->handle == 0)
mgr->handle = 1;
return mgr->handle;
}
struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr,
u8 remote_id)
{
bdaddr_t *dst = mgr->l2cap_conn->dst;
struct hci_conn *hcon;
hcon = hci_conn_add(hdev, AMP_LINK, dst);
if (!hcon)
return NULL;
hcon->state = BT_CONNECT;
hcon->out = true;
hcon->attempt++;
hcon->handle = __next_handle(mgr);
hcon->remote_id = remote_id;
hcon->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;
}
int phylink_gen_key(struct hci_conn *conn, u8 *data, u8 *len, u8 *type)
{
struct hci_dev *hdev = conn->hdev;
struct link_key *key;
u8 keybuf[HCI_AMP_LINK_KEY_SIZE];
u8 gamp_key[HCI_AMP_LINK_KEY_SIZE];
int err;
if (!hci_conn_check_link_mode(conn))
return -EACCES;
BT_DBG("conn %p key_type %d", conn, conn->key_type);
/* Legacy key */
if (conn->key_type < 3) {
BT_ERR("Legacy key type %d", conn->key_type);
return -EACCES;
}
*type = conn->key_type;
*len = HCI_AMP_LINK_KEY_SIZE;
key = hci_find_link_key(hdev, &conn->dst);
/* BR/EDR Link Key concatenated together with itself */
memcpy(&keybuf[0], key->val, HCI_LINK_KEY_SIZE);
memcpy(&keybuf[HCI_LINK_KEY_SIZE], key->val, HCI_LINK_KEY_SIZE);
/* Derive Generic AMP Link Key (gamp) */
err = hmac_sha256(keybuf, HCI_AMP_LINK_KEY_SIZE, "gamp", 4, gamp_key);
if (err) {
BT_ERR("Could not derive Generic AMP Key: err %d", err);
return err;
}
if (conn->key_type == HCI_LK_DEBUG_COMBINATION) {
BT_DBG("Use Generic AMP Key (gamp)");
memcpy(data, gamp_key, HCI_AMP_LINK_KEY_SIZE);
return err;
}
/* Derive Dedicated AMP Link Key: "802b" is 802.11 PAL keyID */
return hmac_sha256(gamp_key, HCI_AMP_LINK_KEY_SIZE, "802b", 4, data);
}
void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle)
{
struct hci_cp_read_local_amp_assoc cp;
struct amp_assoc *loc_assoc = &hdev->loc_assoc;
BT_DBG("%s handle %d", hdev->name, phy_handle);
cp.phy_handle = phy_handle;
cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
cp.len_so_far = cpu_to_le16(loc_assoc->offset);
hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
}
void amp_read_loc_assoc(struct hci_dev *hdev, struct amp_mgr *mgr)
{
struct hci_cp_read_local_amp_assoc cp;
memset(&hdev->loc_assoc, 0, sizeof(struct amp_assoc));
memset(&cp, 0, sizeof(cp));
cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
mgr->state = READ_LOC_AMP_ASSOC;
hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
}