blob: b2597054605b98c453b228343162e96c2db11222 [file] [log] [blame]
/*
* Copyright (c) 2017 Nordic Semiconductor ASA
* Copyright (c) 2015 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdint.h>
#include <bluetooth/hci.h>
#include "ecc.h"
#include "hci_core.h"
#define BT_DBG_ENABLED IS_ENABLED(CONFIG_BT_DEBUG_HCI_CORE)
#define LOG_MODULE_NAME bt_ecc
#include "common/log.h"
static uint8_t pub_key[BT_PUB_KEY_LEN];
static sys_slist_t pub_key_cb_slist;
static bt_dh_key_cb_t dh_key_cb;
static const uint8_t debug_public_key[BT_PUB_KEY_LEN] = {
/* X */
0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc,
0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef,
0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e,
0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20,
/* Y */
0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74,
0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76,
0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63,
0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc
};
bool bt_pub_key_is_debug(uint8_t *pub_key)
{
return memcmp(pub_key, debug_public_key, BT_PUB_KEY_LEN) == 0;
}
int bt_pub_key_gen(struct bt_pub_key_cb *new_cb)
{
struct bt_pub_key_cb *cb;
int err;
/*
* We check for both "LE Read Local P-256 Public Key" and
* "LE Generate DH Key" support here since both commands are needed for
* ECC support. If "LE Generate DH Key" is not supported then there
* is no point in reading local public key.
*/
if (!BT_CMD_TEST(bt_dev.supported_commands, 34, 1) ||
!BT_CMD_TEST(bt_dev.supported_commands, 34, 2)) {
BT_WARN("ECC HCI commands not available");
return -ENOTSUP;
}
if (IS_ENABLED(CONFIG_BT_USE_DEBUG_KEYS)) {
if (!BT_CMD_TEST(bt_dev.supported_commands, 41, 2)) {
BT_WARN("ECC Debug keys HCI command not available");
} else {
atomic_set_bit(bt_dev.flags, BT_DEV_HAS_PUB_KEY);
new_cb->func(debug_public_key);
return 0;
}
}
if (!new_cb) {
return -EINVAL;
}
SYS_SLIST_FOR_EACH_CONTAINER(&pub_key_cb_slist, cb, node) {
if (cb == new_cb) {
BT_WARN("Callback already registered");
return -EALREADY;
}
}
sys_slist_prepend(&pub_key_cb_slist, &new_cb->node);
if (atomic_test_and_set_bit(bt_dev.flags, BT_DEV_PUB_KEY_BUSY)) {
return 0;
}
atomic_clear_bit(bt_dev.flags, BT_DEV_HAS_PUB_KEY);
err = bt_hci_cmd_send_sync(BT_HCI_OP_LE_P256_PUBLIC_KEY, NULL, NULL);
if (err) {
BT_ERR("Sending LE P256 Public Key command failed");
atomic_clear_bit(bt_dev.flags, BT_DEV_PUB_KEY_BUSY);
SYS_SLIST_FOR_EACH_CONTAINER(&pub_key_cb_slist, cb, node) {
if (cb->func) {
cb->func(NULL);
}
}
sys_slist_init(&pub_key_cb_slist);
return err;
}
return 0;
}
const uint8_t *bt_pub_key_get(void)
{
if (IS_ENABLED(CONFIG_BT_USE_DEBUG_KEYS) &&
BT_CMD_TEST(bt_dev.supported_commands, 41, 2)) {
return debug_public_key;
}
if (atomic_test_bit(bt_dev.flags, BT_DEV_HAS_PUB_KEY)) {
return pub_key;
}
return NULL;
}
static int hci_generate_dhkey_v1(const uint8_t *remote_pk)
{
struct bt_hci_cp_le_generate_dhkey *cp;
struct net_buf *buf;
buf = bt_hci_cmd_create(BT_HCI_OP_LE_GENERATE_DHKEY, sizeof(*cp));
if (!buf) {
return -ENOBUFS;
}
cp = net_buf_add(buf, sizeof(*cp));
memcpy(cp->key, remote_pk, sizeof(cp->key));
return bt_hci_cmd_send_sync(BT_HCI_OP_LE_GENERATE_DHKEY, buf, NULL);
}
static int hci_generate_dhkey_v2(const uint8_t *remote_pk, uint8_t key_type)
{
struct bt_hci_cp_le_generate_dhkey_v2 *cp;
struct net_buf *buf;
buf = bt_hci_cmd_create(BT_HCI_OP_LE_GENERATE_DHKEY_V2, sizeof(*cp));
if (!buf) {
return -ENOBUFS;
}
cp = net_buf_add(buf, sizeof(*cp));
memcpy(cp->key, remote_pk, sizeof(cp->key));
cp->key_type = key_type;
return bt_hci_cmd_send_sync(BT_HCI_OP_LE_GENERATE_DHKEY_V2, buf, NULL);
}
int bt_dh_key_gen(const uint8_t remote_pk[BT_PUB_KEY_LEN], bt_dh_key_cb_t cb)
{
int err;
if (dh_key_cb == cb) {
return -EALREADY;
}
if (dh_key_cb || atomic_test_bit(bt_dev.flags, BT_DEV_PUB_KEY_BUSY)) {
return -EBUSY;
}
if (!atomic_test_bit(bt_dev.flags, BT_DEV_HAS_PUB_KEY)) {
return -EADDRNOTAVAIL;
}
dh_key_cb = cb;
if (IS_ENABLED(CONFIG_BT_USE_DEBUG_KEYS) &&
BT_CMD_TEST(bt_dev.supported_commands, 41, 2)) {
err = hci_generate_dhkey_v2(remote_pk,
BT_HCI_LE_KEY_TYPE_DEBUG);
} else {
err = hci_generate_dhkey_v1(remote_pk);
}
if (err) {
dh_key_cb = NULL;
BT_WARN("Failed to generate DHKey (err %d)", err);
return err;
}
return 0;
}
void bt_hci_evt_le_pkey_complete(struct net_buf *buf)
{
struct bt_hci_evt_le_p256_public_key_complete *evt = (void *)buf->data;
struct bt_pub_key_cb *cb;
BT_DBG("status: 0x%02x", evt->status);
atomic_clear_bit(bt_dev.flags, BT_DEV_PUB_KEY_BUSY);
if (!evt->status) {
memcpy(pub_key, evt->key, BT_PUB_KEY_LEN);
atomic_set_bit(bt_dev.flags, BT_DEV_HAS_PUB_KEY);
}
SYS_SLIST_FOR_EACH_CONTAINER(&pub_key_cb_slist, cb, node) {
if (cb->func) {
cb->func(evt->status ? NULL : pub_key);
}
}
sys_slist_init(&pub_key_cb_slist);
}
void bt_hci_evt_le_dhkey_complete(struct net_buf *buf)
{
struct bt_hci_evt_le_generate_dhkey_complete *evt = (void *)buf->data;
BT_DBG("status: 0x%02x", evt->status);
if (dh_key_cb) {
bt_dh_key_cb_t cb = dh_key_cb;
dh_key_cb = NULL;
cb(evt->status ? NULL : evt->dhkey);
}
}