Manual Pages  — NG_BTSOCKET

The Bluetooth raw HCI socket address is defined as follows:

/* Bluetooth version of struct sockaddr for raw HCI sockets */
struct sockaddr_hci {
        u_char  hci_len;      /* total length */
        u_char  hci_family;   /* address family */
        char    hci_node[32]; /* address (size == NG_NODESIZ ) */
};

Raw HCI sockets support a number of ioctl(2) requests such as:

SIOC_HCI_RAW_NODE_GET_STATE
	Returns current state for the HCI node.
SIOC_HCI_RAW_NODE_INIT
	Turn on "inited" bit for the HCI node.
SIOC_HCI_RAW_NODE_GET_DEBUG
	Returns current debug level for the HCI node.
SIOC_HCI_RAW_NODE_SET_DEBUG
	Sets current debug level for the HCI node.
SIOC_HCI_RAW_NODE_GET_BUFFER
	Returns current state of data buffers for the HCI node.
SIOC_HCI_RAW_NODE_GET_BDADDR
	Returns BD_ADDR for the HCI node.
SIOC_HCI_RAW_NODE_GET_FEATURES
	Returns the list of features supported by hardware for the HCI node.
SIOC_HCI_RAW_NODE_GET_STAT
	Returns various statistic counters for the HCI node.
SIOC_HCI_RAW_NODE_RESET_STAT
	Resets all statistic counters for the HCI node to zero.
SIOC_HCI_RAW_NODE_FLUSH_NEIGHBOR_CACHE
	Remove all neighbor cache entries for the HCI node.
SIOC_HCI_RAW_NODE_GET_NEIGHBOR_CACHE
	Returns content of the neighbor cache for the HCI node.
SIOC_HCI_RAW_NODE_GET_CON_LIST
	Returns list of active baseband connections (i.e., ACL and SCO links) for the HCI node.
SIOC_HCI_RAW_NODE_GET_LINK_POLICY_MASK
	Returns current link policy settings mask for the HCI node.
SIOC_HCI_RAW_NODE_SET_LINK_POLICY_MASK
	Sets current link policy settings mask for the HCI node.
SIOC_HCI_RAW_NODE_GET_PACKET_MASK
	Returns current packet mask for the HCI node.
SIOC_HCI_RAW_NODE_SET_PACKET_MASK
	Sets current packet mask for the HCI node.
SIOC_HCI_RAW_NODE_GET_ROLE_SWITCH
	Returns current value of the role switch parameter for the HCI node.
SIOC_HCI_RAW_NODE_SET_ROLE_SWITCH
	Sets new value of the role switch parameter for the HCI node.

The net.bluetooth.hci.sockets.raw.ioctl_timeout variable, that can be examined and set via sysctl(8), controls the control request timeout (in seconds) for raw HCI sockets.

Raw HCI sockets support filters. The application can filter certain HCI datagram types. For HCI event datagrams the application can set additional filter. The raw HCI socket filter defined as follows:

/*
 * Raw HCI socket filter.
 *
 * For packet mask use (1 << (HCI packet indicator - 1))
 * For event mask use (1 << (Event - 1))
 */

struct ng_btsocket_hci_raw_filter {
        bitstr_t bit_decl(packet_mask, 32);
        bitstr_t bit_decl(event_mask, (NG_HCI_EVENT_MASK_SIZE * 8));
};

The SO_HCI_RAW_FILTER option defined at SOL_HCI_RAW level can be used to obtain via getsockopt(2) or change via setsockopt(2) raw HCI socket's filter.

/* Bluetooth version of struct sockaddr for L2CAP sockets */
struct sockaddr_l2cap {
        u_char    l2cap_len;    /* total length */
        u_char    l2cap_family; /* address family */
        uint16_t  l2cap_psm;    /* Protocol/Service Multiplexor */
        bdaddr_t  l2cap_bdaddr; /* address */
};

Raw L2CAP sockets support number of ioctl(2) requests such as:

SIOC_L2CAP_NODE_GET_FLAGS
	Returns current state for the L2CAP node.
SIOC_L2CAP_NODE_GET_DEBUG
	Returns current debug level for the L2CAP node.
SIOC_L2CAP_NODE_SET_DEBUG
	Sets current debug level for the L2CAP node.
SIOC_L2CAP_NODE_GET_CON_LIST
	Returns list of active baseband connections (i.e., ACL links) for the L2CAP node.
SIOC_L2CAP_NODE_GET_CHAN_LIST
	Returns list of active channels for the L2CAP node.
SIOC_L2CAP_NODE_GET_AUTO_DISCON_TIMO
	Returns current value of the auto disconnect timeout for the L2CAP node.
SIOC_L2CAP_NODE_SET_AUTO_DISCON_TIMO
	Sets current value of the auto disconnect timeout for the L2CAP node.
SIOC_L2CAP_L2CA_PING
	Issues L2CAP ECHO_REQUEST.
SIOC_L2CAP_L2CA_GET_INFO
	Issues L2CAP GET_INFO request.

The net.bluetooth.l2cap.sockets.raw.ioctl_timeout variable, that can be examined and set via sysctl(8), controls the control request timeout (in seconds) for raw L2CAP sockets.

SOCK_SEQPACKET L2CAP sockets

L2CAP sockets support "wildcard addressing". In this case, socket must be bound to NG_HCI_BDADDR_ANY address. Note that PSM (Protocol/Service Multiplexor) field is always required. Once a connection has been established, the socket's address is fixed by the peer entity's location. The address assigned to the socket is the address associated with the Bluetooth device through which packets are being transmitted and received, and PSM (Protocol/Service Multiplexor).

L2CAP sockets support number of options defined at SOL_L2CAP level which can be set with setsockopt(2) and tested with getsockopt(2):

SO_L2CAP_IMTU
	Get (set) maximum payload size the local socket is capable of accepting.
SO_L2CAP_OMTU
	Get maximum payload size the remote socket is capable of accepting.
SO_L2CAP_IFLOW
	Get incoming flow specification for the socket. Not implemented.
SO_L2CAP_OFLOW
	Get (set) outgoing flow specification for the socket. Not implemented.
SO_L2CAP_FLUSH
	Get (set) value of the flush timeout. Not implemented.

/* Bluetooth version of struct sockaddr for RFCOMM sockets */
struct sockaddr_rfcomm {
        u_char   rfcomm_len;     /* total length */
        u_char   rfcomm_family;  /* address family */
        bdaddr_t rfcomm_bdaddr;  /* address */
        uint8_t  rfcomm_channel; /* channel */
};

RFCOMM sockets support "wildcard addressing". In this case, socket must be bound to NG_HCI_BDADDR_ANY address. Note that RFCOMM channel field is always required. Once a connection has been established, the socket's address is fixed by the peer entity's location. The address assigned to the socket is the address associated with the Bluetooth device through which packets are being transmitted and received, and RFCOMM channel.

The following options, which can be tested with getsockopt(2) call, are defined at SOL_RFCOMM level for RFCOMM sockets:

SO_RFCOMM_MTU
	Returns the maximum transfer unit size (in bytes) for the underlying RFCOMM channel. Note that application still can write/read bigger chunks to/from the socket.
SO_RFCOMM_FC_INFO
	Return the flow control information for the underlying RFCOMM channel.

The net.bluetooth.rfcomm.sockets.stream.timeout variable, that can be examined and set via sysctl(8), controls the connection timeout (in seconds) for RFCOMM sockets.