static uint8_t att_mtu_rsp(struct bt_att *att, struct net_buf *buf)
{
struct bt_att_exchange_mtu_rsp *rsp;
uint16_t mtu;
if (!att) {
return 0;
}
rsp = (void *)buf->data;
mtu = sys_le16_to_cpu(rsp->mtu);
BT_DBG("Server MTU %u", mtu);
/* Check if MTU is valid */
if (mtu < BT_ATT_DEFAULT_LE_MTU) {
return att_handle_rsp(att, NULL, 0, BT_ATT_ERR_INVALID_PDU);
}
att->chan.rx.mtu = min(mtu, CONFIG_BLUETOOTH_ATT_MTU);
/* BLUETOOTH SPECIFICATION Version 4.2 [Vol 3, Part F] page 484:
*
* A device's Exchange MTU Request shall contain the same MTU as the
* device's Exchange MTU Response (i.e. the MTU shall be symmetric).
*/
att->chan.tx.mtu = att->chan.rx.mtu;
BT_DBG("Negotiated MTU %u", att->chan.rx.mtu);
return att_handle_rsp(att, rsp, buf->len, 0);
}
static uint8_t att_handle_exec_write_rsp(struct bt_att *att,
struct net_buf *buf)
{
BT_DBG("");
return att_handle_rsp(att, buf->data, buf->len, 0);
}
static void bt_att_disconnected(struct bt_l2cap_chan *chan)
{
struct bt_att *att = CONTAINER_OF(chan, struct bt_att, chan);
BT_DBG("chan %p cid 0x%04x", chan, chan->tx.cid);
/* Notify client if request is pending */
att_handle_rsp(att, NULL, 0, BT_ATT_ERR_UNLIKELY);
bt_gatt_disconnected(chan->conn);
memset(att, 0, sizeof(*att));
}
static uint8_t att_error_rsp(struct bt_att *att, struct net_buf *buf)
{
struct bt_att_req *req = &att->req;
struct bt_att_error_rsp *rsp;
struct bt_att_hdr *hdr;
uint8_t err;
rsp = (void *)buf->data;
BT_DBG("request 0x%02x handle 0x%04x error 0x%02x", rsp->request,
sys_le16_to_cpu(rsp->handle), rsp->error);
if (!req->buf) {
err = BT_ATT_ERR_UNLIKELY;
goto done;
}
hdr = (void *)req->buf->data;
err = rsp->request == hdr->code ? rsp->error : BT_ATT_ERR_UNLIKELY;
#if defined(CONFIG_BLUETOOTH_SMP)
if (req->retrying) {
goto done;
}
/* Check if security needs to be changed */
if (!att_change_security(att->chan.conn, err)) {
req->retrying = true;
/* Wait security_changed: TODO: Handle fail case */
return 0;
}
#endif /* CONFIG_BLUETOOTH_SMP */
done:
return att_handle_rsp(att, NULL, 0, err);
}