zephyr/subsys/bluetooth/host/keys.c
Joakim Andersson 6c6bd8c49e Bluetooth: host: Fix directed advertising from privacy-disabled peer
Fix directed advertising from privacy disabled peer. In this case we
need to have the local IRK in the controllers resolving list in order to
have the controller resolve the initiator address of the directed
advertising pdu (ADV_DIR_IND).

Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>
2020-03-23 12:44:44 +02:00

436 lines
9.4 KiB
C

/* keys.c - Bluetooth key handling */
/*
* Copyright (c) 2015-2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr.h>
#include <string.h>
#include <stdlib.h>
#include <sys/atomic.h>
#include <sys/util.h>
#include <settings/settings.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/conn.h>
#include <bluetooth/hci.h>
#define BT_DBG_ENABLED IS_ENABLED(CONFIG_BT_DEBUG_KEYS)
#define LOG_MODULE_NAME bt_keys
#include "common/log.h"
#include "common/rpa.h"
#include "gatt_internal.h"
#include "hci_core.h"
#include "smp.h"
#include "settings.h"
#include "keys.h"
static struct bt_keys key_pool[CONFIG_BT_MAX_PAIRED];
#define BT_KEYS_STORAGE_LEN_COMPAT (BT_KEYS_STORAGE_LEN - sizeof(uint32_t))
#if IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST)
static u32_t aging_counter_val;
static struct bt_keys *last_keys_updated;
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
struct bt_keys *bt_keys_get_addr(u8_t id, const bt_addr_le_t *addr)
{
struct bt_keys *keys;
int i;
size_t first_free_slot = ARRAY_SIZE(key_pool);
BT_DBG("%s", bt_addr_le_str(addr));
for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
keys = &key_pool[i];
if (keys->id == id && !bt_addr_le_cmp(&keys->addr, addr)) {
return keys;
}
if (first_free_slot == ARRAY_SIZE(key_pool) &&
!bt_addr_le_cmp(&keys->addr, BT_ADDR_LE_ANY)) {
first_free_slot = i;
}
}
#if IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST)
if (first_free_slot == ARRAY_SIZE(key_pool)) {
struct bt_keys *oldest = &key_pool[0];
for (i = 1; i < ARRAY_SIZE(key_pool); i++) {
struct bt_keys *current = &key_pool[i];
if (current->aging_counter < oldest->aging_counter) {
oldest = current;
}
}
bt_unpair(oldest->id, &oldest->addr);
if (!bt_addr_le_cmp(&oldest->addr, BT_ADDR_LE_ANY)) {
first_free_slot = oldest - &key_pool[0];
}
}
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
if (first_free_slot < ARRAY_SIZE(key_pool)) {
keys = &key_pool[first_free_slot];
keys->id = id;
bt_addr_le_copy(&keys->addr, addr);
#if IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST)
keys->aging_counter = ++aging_counter_val;
last_keys_updated = keys;
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
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_foreach_bond(u8_t id, void (*func)(const struct bt_bond_info *info,
void *user_data),
void *user_data)
{
int i;
for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
struct bt_keys *keys = &key_pool[i];
if (keys->keys && keys->id == id) {
struct bt_bond_info info;
bt_addr_le_copy(&info.addr, &keys->addr);
func(&info, user_data);
}
}
}
void bt_keys_foreach(int type, void (*func)(struct bt_keys *keys, void *data),
void *data)
{
int i;
for (i = 0; i < ARRAY_SIZE(key_pool); i++) {
if ((key_pool[i].keys & type)) {
func(&key_pool[i], data);
}
}
}
struct bt_keys *bt_keys_find(int type, u8_t id, 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) && key_pool[i].id == id &&
!bt_addr_le_cmp(&key_pool[i].addr, addr)) {
return &key_pool[i];
}
}
return NULL;
}
struct bt_keys *bt_keys_get_type(int type, u8_t id, 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, id, addr);
if (keys) {
return keys;
}
keys = bt_keys_get_addr(id, addr);
if (!keys) {
return NULL;
}
bt_keys_add_type(keys, type);
return keys;
}
struct bt_keys *bt_keys_find_irk(u8_t id, 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 (key_pool[i].id == id &&
!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 (key_pool[i].id != id) {
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(u8_t id, 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 (key_pool[i].id == id &&
!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("%s (keys 0x%04x)", bt_addr_le_str(&keys->addr), keys->keys);
if ((IS_ENABLED(CONFIG_BT_CENTRAL) && IS_ENABLED(CONFIG_BT_PRIVACY)) ||
keys->keys & BT_KEYS_IRK) {
bt_id_del(keys);
}
if (IS_ENABLED(CONFIG_BT_SETTINGS)) {
char key[BT_SETTINGS_KEY_MAX];
/* Delete stored keys from flash */
if (keys->id) {
char id[4];
u8_to_dec(id, sizeof(id), keys->id);
bt_settings_encode_key(key, sizeof(key), "keys",
&keys->addr, id);
} else {
bt_settings_encode_key(key, sizeof(key), "keys",
&keys->addr, NULL);
}
BT_DBG("Deleting key %s", log_strdup(key));
settings_delete(key);
}
(void)memset(keys, 0, sizeof(*keys));
}
#if defined(CONFIG_BT_SETTINGS)
int bt_keys_store(struct bt_keys *keys)
{
char key[BT_SETTINGS_KEY_MAX];
int err;
if (keys->id) {
char id[4];
u8_to_dec(id, sizeof(id), keys->id);
bt_settings_encode_key(key, sizeof(key), "keys", &keys->addr,
id);
} else {
bt_settings_encode_key(key, sizeof(key), "keys", &keys->addr,
NULL);
}
err = settings_save_one(key, keys->storage_start, BT_KEYS_STORAGE_LEN);
if (err) {
BT_ERR("Failed to save keys (err %d)", err);
return err;
}
BT_DBG("Stored keys for %s (%s)", bt_addr_le_str(&keys->addr),
log_strdup(key));
return 0;
}
static int keys_set(const char *name, size_t len_rd, settings_read_cb read_cb,
void *cb_arg)
{
struct bt_keys *keys;
bt_addr_le_t addr;
u8_t id;
size_t len;
int err;
char val[BT_KEYS_STORAGE_LEN];
const char *next;
if (!name) {
BT_ERR("Insufficient number of arguments");
return -EINVAL;
}
len = read_cb(cb_arg, val, sizeof(val));
if (len < 0) {
BT_ERR("Failed to read value (err %zu)", len);
return -EINVAL;
}
BT_DBG("name %s val %s", log_strdup(name),
(len) ? bt_hex(val, sizeof(val)) : "(null)");
err = bt_settings_decode_key(name, &addr);
if (err) {
BT_ERR("Unable to decode address %s", name);
return -EINVAL;
}
settings_name_next(name, &next);
if (!next) {
id = BT_ID_DEFAULT;
} else {
id = strtol(next, NULL, 10);
}
if (!len) {
keys = bt_keys_find(BT_KEYS_ALL, id, &addr);
if (keys) {
(void)memset(keys, 0, sizeof(*keys));
BT_DBG("Cleared keys for %s", bt_addr_le_str(&addr));
} else {
BT_WARN("Unable to find deleted keys for %s",
bt_addr_le_str(&addr));
}
return 0;
}
keys = bt_keys_get_addr(id, &addr);
if (!keys) {
BT_ERR("Failed to allocate keys for %s", bt_addr_le_str(&addr));
return -ENOMEM;
}
if (len != BT_KEYS_STORAGE_LEN) {
do {
/* Load shorter structure for compatibility with old
* records format with no counter.
*/
if (IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST) &&
len == BT_KEYS_STORAGE_LEN_COMPAT) {
BT_WARN("Keys for %s have no aging counter",
bt_addr_le_str(&addr));
memcpy(keys->storage_start, val, len);
continue;
}
BT_ERR("Invalid key length %zu != %zu", len,
BT_KEYS_STORAGE_LEN);
bt_keys_clear(keys);
return -EINVAL;
} while (0);
} else {
memcpy(keys->storage_start, val, len);
}
BT_DBG("Successfully restored keys for %s", bt_addr_le_str(&addr));
#if IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST)
if (aging_counter_val < keys->aging_counter) {
aging_counter_val = keys->aging_counter;
}
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
return 0;
}
static void id_add(struct bt_keys *keys, void *user_data)
{
bt_id_add(keys);
}
static int keys_commit(void)
{
BT_DBG("");
/* We do this in commit() rather than add() since add() may get
* called multiple times for the same address, especially if
* the keys were already removed.
*/
if (IS_ENABLED(CONFIG_BT_CENTRAL) && IS_ENABLED(CONFIG_BT_PRIVACY)) {
bt_keys_foreach(BT_KEYS_ALL, id_add, NULL);
} else {
bt_keys_foreach(BT_KEYS_IRK, id_add, NULL);
}
return 0;
}
SETTINGS_STATIC_HANDLER_DEFINE(bt_keys, "bt/keys", NULL, keys_set, keys_commit,
NULL);
#endif /* CONFIG_BT_SETTINGS */
#if IS_ENABLED(CONFIG_BT_KEYS_OVERWRITE_OLDEST)
void bt_keys_update_usage(u8_t id, const bt_addr_le_t *addr)
{
struct bt_keys *keys = bt_keys_find_addr(id, addr);
if (!keys) {
return;
}
if (last_keys_updated == keys) {
return;
}
keys->aging_counter = ++aging_counter_val;
last_keys_updated = keys;
BT_DBG("Aging counter for %s is set to %u", bt_addr_le_str(addr),
keys->aging_counter);
if (IS_ENABLED(CONFIG_BT_KEYS_SAVE_AGING_COUNTER_ON_PAIRING)) {
bt_keys_store(keys);
}
}
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */