/* keys.c - Bluetooth key handling */

/*
 * Copyright (c) 2015-2016 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr.h>
#include <string.h>
#include <atomic.h>
#include <misc/util.h>

#include <bluetooth/bluetooth.h>
#include <bluetooth/conn.h>
#include <bluetooth/hci.h>

#define BT_DBG_ENABLED IS_ENABLED(CONFIG_BT_DEBUG_KEYS)
#include "common/log.h"

#include "common/rpa.h"
#include "hci_core.h"
#include "smp.h"
#include "keys.h"

static struct bt_keys key_pool[CONFIG_BT_MAX_PAIRED];

struct bt_keys *bt_keys_get_addr(const bt_addr_le_t *addr)
{
	struct bt_keys *keys;
	int i;

	BT_DBG("%s", bt_addr_le_str(addr));

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		keys = &key_pool[i];

		if (!bt_addr_le_cmp(&keys->addr, addr)) {
			return keys;
		}

		if (!bt_addr_le_cmp(&keys->addr, BT_ADDR_LE_ANY)) {
			bt_addr_le_copy(&keys->addr, addr);
			BT_DBG("created %p for %s", keys, bt_addr_le_str(addr));
			return keys;
		}
	}

	BT_DBG("unable to create keys for %s", bt_addr_le_str(addr));

	return NULL;
}

void bt_keys_foreach(int type, void (*func)(struct bt_keys *keys))
{
	int i;

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		if ((key_pool[i].keys & type)) {
			func(&key_pool[i]);
		}
	}
}

struct bt_keys *bt_keys_find(int type, const bt_addr_le_t *addr)
{
	int i;

	BT_DBG("type %d %s", type, bt_addr_le_str(addr));

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		if ((key_pool[i].keys & type) &&
		    !bt_addr_le_cmp(&key_pool[i].addr, addr)) {
			return &key_pool[i];
		}
	}

	return NULL;
}

struct bt_keys *bt_keys_get_type(int type, const bt_addr_le_t *addr)
{
	struct bt_keys *keys;

	BT_DBG("type %d %s", type, bt_addr_le_str(addr));

	keys = bt_keys_find(type, addr);
	if (keys) {
		return keys;
	}

	keys = bt_keys_get_addr(addr);
	if (!keys) {
		return NULL;
	}

	bt_keys_add_type(keys, type);

	return keys;
}

struct bt_keys *bt_keys_find_irk(const bt_addr_le_t *addr)
{
	int i;

	BT_DBG("%s", bt_addr_le_str(addr));

	if (!bt_addr_le_is_rpa(addr)) {
		return NULL;
	}

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		if (!(key_pool[i].keys & BT_KEYS_IRK)) {
			continue;
		}

		if (!bt_addr_cmp(&addr->a, &key_pool[i].irk.rpa)) {
			BT_DBG("cached RPA %s for %s",
			       bt_addr_str(&key_pool[i].irk.rpa),
			       bt_addr_le_str(&key_pool[i].addr));
			return &key_pool[i];
		}
	}

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		if (!(key_pool[i].keys & BT_KEYS_IRK)) {
			continue;
		}

		if (bt_rpa_irk_matches(key_pool[i].irk.val, &addr->a)) {
			BT_DBG("RPA %s matches %s",
			       bt_addr_str(&key_pool[i].irk.rpa),
			       bt_addr_le_str(&key_pool[i].addr));

			bt_addr_copy(&key_pool[i].irk.rpa, &addr->a);

			return &key_pool[i];
		}
	}

	BT_DBG("No IRK for %s", bt_addr_le_str(addr));

	return NULL;
}

struct bt_keys *bt_keys_find_addr(const bt_addr_le_t *addr)
{
	int i;

	BT_DBG("%s", bt_addr_le_str(addr));

	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
		if (!bt_addr_le_cmp(&key_pool[i].addr, addr)) {
			return &key_pool[i];
		}
	}

	return NULL;
}

void bt_keys_add_type(struct bt_keys *keys, int type)
{
	keys->keys |= type;
}

void bt_keys_clear(struct bt_keys *keys)
{
	BT_DBG("keys for %s", bt_addr_le_str(&keys->addr));

	if (keys->keys & BT_KEYS_IRK) {
		bt_id_del(keys);
	}

	memset(keys, 0, sizeof(*keys));
}

void bt_keys_clear_all(void)
{
	bt_keys_foreach(BT_KEYS_ALL, bt_keys_clear);
}