text: /* keys.c - Bluetooth key handling */
  
  /*
   * Copyright (c) 2015 Intel Corporation
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #include <string.h>
  #include <nanokernel.h>
  #include <atomic.h>
  #include <misc/util.h>
  
  #include <bluetooth/log.h>
  #include <bluetooth/bluetooth.h>
  #include <bluetooth/conn.h>
  #include <bluetooth/hci.h>
  
  #include "hci_core.h"
  #include "smp.h"
  #include "keys.h"
  
  #if !defined(CONFIG_BLUETOOTH_DEBUG_KEYS)
  #undef BT_DBG
  #define BT_DBG(fmt, ...)
  #endif
  
  static struct bt_keys key_pool[CONFIG_BLUETOOTH_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_clear(struct bt_keys *keys, int type)
  {
  	BT_DBG("keys for %s type %d", bt_addr_le_str(&keys->addr), type);
  
  	keys->keys &= ~type;
  
  	if (!keys->keys) {
  		memset(keys, 0, sizeof(*keys));
  	}
  }
  
  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;
  }
  
  void bt_keys_add_type(struct bt_keys *keys, int type)
  {
  	keys->keys |= type;
  }
  
  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((bt_addr_t *)addr->val,
  				 &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_smp_irk_matches(key_pool[i].irk.val,
  				       (bt_addr_t *)addr->val)) {
  			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,
  				     (bt_addr_t *)addr->val);
  
  			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;
  }
  
  #if defined(CONFIG_BLUETOOTH_BREDR)
  static struct bt_keys *bt_keys_get_addr_br(const bt_addr_t *addr)
  {
  	struct bt_keys *keys;
  	int i;
  
  	BT_DBG("%s", bt_addr_str(addr));
  
  	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
  		keys = &key_pool[i];
  
  		/*
  		 * When both LE and BR/EDR keys are for the same device,
  		 * the bt_addr_le_t is the public address, i.e. the same
  		 * as the BR/EDR address.
  		 */
  		if (keys->addr.type == BT_ADDR_LE_PUBLIC &&
  		    !bt_addr_cmp((const bt_addr_t *)keys->addr.val, addr)) {
  			return keys;
  		}
  
  		/*
  		 * BT_ADDR_LE_ANY has the same type of as BT_ADDR_LE_PUBLIC
  		 * value. No need to make redudant comparision against
  		 * BT_ADDR_LE_PUBLIC.
  		 */
  		if (!bt_addr_le_cmp(&keys->addr, BT_ADDR_LE_ANY)) {
  			bt_addr_copy((bt_addr_t *)keys->addr.val, addr);
  			BT_DBG("created %p for %s", keys, bt_addr_str(addr));
  			return keys;
  		}
  	}
  
  	BT_DBG("unable to create keys for %s", bt_addr_str(addr));
  
  	return NULL;
  }
  
  struct bt_keys *bt_keys_find_link_key(const bt_addr_t *addr)
  {
  	struct bt_keys *keys;
  	int i;
  
  	BT_DBG("%s", bt_addr_str(addr));
  
  	for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
  		keys = &key_pool[i];
  
  		/*
  		 * When both LE and BR/EDR keys are for the same device,
  		 * the bt_addr_le_t is the public address, i.e. the same
  		 * as the BR/EDR address.
  		 */
  		if (keys->addr.type == BT_ADDR_LE_PUBLIC &&
  		    (keys->keys & BT_KEYS_LINK_KEY) &&
  		    !bt_addr_cmp((const bt_addr_t *)keys->addr.val, addr)) {
  			return keys;
  		}
  	}
  
  	return NULL;
  }
  
  struct bt_keys *bt_keys_get_link_key(const bt_addr_t *addr)
  {
  	struct bt_keys *keys;
  
  	BT_DBG("%s", bt_addr_str(addr));
  
  	keys = bt_keys_find_link_key(addr);
  	if (keys) {
  		return keys;
  	}
  
  	keys = bt_keys_get_addr_br(addr);
  	if (!keys) {
  		return NULL;
  	}
  
  	bt_keys_add_type(keys, BT_KEYS_LINK_KEY);
  
  	return keys;
  }
  #endif /* CONFIG_BLUETOOTH_BREDR */
  