BLUETOOTH(4)						   BSD Kernel Interfaces Manual 					      BLUETOOTH(4)

NAME

     bluetooth -- Bluetooth Protocol Family

SYNOPSIS

     #include <netbt/bluetooth.h>
     #include <netbt/hci.h>
     #include <netbt/l2cap.h>
     #include <netbt/rfcomm.h>

DESCRIPTION

     The Bluetooth Protocol Family

ADDRESSING

     Bluetooth Protocol Family sockets all use a sockaddr_bt structure which contains a Bluetooth Device Address (BDADDR).  This consists of a six
     byte string in least significant byte first order.

	   struct sockaddr_bt {
		   uint8_t	   bt_len;
		   sa_family_t	   bt_family;
		   bdaddr_t	   bt_bdaddr;
		   uint16_t	   bt_psm;
		   uint8_t	   bt_channel;
	   };

     The local address used by the socket can be set with bind(2).

PROTOCOLS

     Protocols included are:

     BTPROTO_HCI
	 This gives raw access to the Host Controller Interface of local devices using the HCI protocol as described in the Bluetooth Core Speci-
	 fication.  Any user may open an HCI socket but there are limitations on what unprivileged users can send and receive.	The local address
	 specified by bind(2) may be used to select the device that the socket will receive packets from.  If BDADDR_ANY is specified then the
	 socket will receive packets from all devices on the system.  connect(2) may be used to create connections such that packets sent with
	 send(2) will be delivered to the specified device, otherwise sendto(2) should be used.

	 The bt_psm and bt_channel fields in the sockaddr_bt structure are ignored by HCI protocol code and should be set to zero.

	 HCI socket options:

	 SO_HCI_EVT_FILTER [struct hci_filter]
	     This filter controls which events will be received at the socket.	See <netbt/hci.h> for available events.  By default, Command_Com-
	     plete and Command_Status events only are enabled.

	 SO_HCI_PKT_FILTER [struct hci_filter]
	     This filter controls the type of packets that will be received at the socket.  By default, Event packets only are enabled.

	 SO_HCI_DIRECTION [int]
	     When set, this enables control messages on packets received at the socket indicating the direction of travel of the packet.

	 HCI sysctl(8) controls:

	 net.bluetooth.hci.sendspace
	      Default send buffer size for HCI sockets.

	 net.bluetooth.hci.recvspace
	      Default receive buffer size for HCI sockets

	 net.bluetooth.hci.acl_expiry
	      If set, this is the time in seconds after which unused ACL data connections will be expired.  If zero, connections will not be
	      closed.

	 net.bluetooth.hci.memo_expiry
	      Time, in seconds, that the system will keep records of Bluetooth devices in the vicinity after an Inquiry Response packet has been
	      received.  This information is used for routing purposes.

	 net.bluetooth.hci.eventq_max
	      The maximum number of packets on the low level Event queue.

	 net.bluetooth.hci.aclrxq_max
	      The maximum number of packets on the low level ACL queue.

	 net.bluetooth.hci.scorxq_max
	      The maximum number of packets on the low level SCO queue.

     BTPROTO_L2CAP
	 L2CAP sockets give sequential packet access over channels to other Bluetooth devices and make use of the bt_psm field in the sockaddr_bt
	 structure to select the Protocol/Sevice Multiplexer to specify when making connections.  If the special value of L2CAP_PSM_ANY is bound
	 when the listen(2) call is made, the next available PSM from the dynamic range above 0x1001 will be selected and may be discovered using
	 the getsockname(2) call.

	 L2CAP socket options:

	 SO_L2CAP_IMTU [uint16_t]
	      Incoming MTU

	 SO_L2CAP_OMTU [uint16_t]
	      Outgoing MTU (read-only)

	 SO_L2CAP_LM [int]
	      Link Mode.  The following bits may be set:

	      L2CAP_LM_AUTH	Request authentication (pairing).
	      L2CAP_LM_ENCRYPT	Request encryption (includes auth).
	      L2CAP_LM_SECURE	Request secured link (encryption, plus change link key).

	      Link mode settings will be applied to the baseband link during L2CAP connection establishment.  If the L2CAP connection is already
	      established, EINPROGRESS may be returned, and it is not possible to guarantee that data already queued (from either end) will not be
	      delivered.  If the mode change fails, the L2CAP connection will be aborted.

	 L2CAP sysctl(8) controls:

	 net.bluetooth.l2cap.sendspace
	      Default send buffer size for L2CAP sockets.

	 net.bluetooth.l2cap.recvspace
	      Default receive buffer size for L2CAP sockets.

	 net.bluetooth.l2cap.rtx
	      Response Timeout eXpiry for L2CAP signals.

	 net.bluetooth.l2cap.ertx
	      Extended Response Timeout eXpiry for L2CAP signals.

     BTPROTO_RFCOMM
	 RFCOMM sockets provide streamed data over Bluetooth connection and make use of the bt_psm, and bt_channel fields in the sockaddr_bt
	 structure.  The channel number must be between 1 and 30 inclusive except that if the special value RFCOMM_CHANNEL_ANY is bound, when the
	 listen(2) call is made, the first unused channel for the relevant bdaddr will be allocated and may be discovered using the getsockname(2)
	 call.	If no PSM is specified, a default value of L2CAP_PSM_RFCOMM (0x0003) will be used.

	 RFCOMM socket options:

	 SO_RFCOMM_MTU [uint16_t]
	      Maximum Frame Size to use for this link.

	 SO_RFCOMM_LM [int]
	      Link Mode.  The following bits may be set at any time:

	      RFCOMM_LM_AUTH	 Request authentication (pairing).
	      RFCOMM_LM_ENCRYPT  Request encryption (includes auth).
	      RFCOMM_LM_SECURE	 Request secured link (encryption, plus change link key).

	      Link mode settings will be applied to the baseband link during RFCOMM connection establishment.  If the RFCOMM connection is already
	      established, EINPROGRESS may be returned, and it is not possible to guarantee that data already queued (from either end) will not be
	      delivered.  If the mode change fails, the RFCOMM connection will be aborted.

	 RFCOMM sysctl(8) controls:

	 net.bluetooth.rfcomm.sendspace
	      Default send buffer size for RFCOMM sockets.

	 net.bluetooth.rfcomm.recvspace
	      Default receive buffer size for RFCOMM sockets.

	 net.bluetooth.rfcomm.default_mtu
	      Maximum Frame Size (N1)

	 net.bluetooth.ack_timeout
	      Acknowledgement Timer (T1)

	 net.bluetooth.mcc_timeout
	      Response Timer for Multiplexer Control Channel (T2)

     BTPROTO_SCO
	 SCO sockets provide sequential packet access to time sensitive data channels over Bluetooth connections, typically used for audio data.

	 SCO socket options:

	 SO_SCO_MTU [uint16_t]
	      Maximum packet size for use on this link.  This is read-only and will be set by the protocol code when a connection is made.  Cur-
	      rently, due to limitations in the ubt(4) driver, the SCO protocol code will only accept packets with exactly this size.

	 SO_SCO_HANDLE [uint16_t]
	      Connection handle for this link.	This is read-only and provided for informational purposes only.

	 SCO sysctl(8) controls:

	 net.bluetooth.sco.sendspace
	      Default send buffer size for SCO sockets.

	 net.bluetooth.sco.recvspace
	      Default receive buffer size for SCO sockets.

INFORMATION

     The following ioctl(2) calls may be used to manipulate Bluetooth devices.	The ioctl(2) must be made on BTPROTO_HCI sockets.  All of the
     requests take a btreq structure defined as follows as their parameter and unless otherwise specified, use the btr_name field to identify the
     device.

     struct btreq {
	 char btr_name[HCI_DEVNAME_SIZE];    /* device name */

	 union {
	     struct {
		 bdaddr_t btri_bdaddr;	     /* device bdaddr */
		 uint16_t btri_flags;	     /* flags */
		 uint16_t btri_num_cmd;      /* # of free cmd buffers */
		 uint16_t btri_num_acl;      /* # of free ACL buffers */
		 uint16_t btri_num_sco;      /* # of free SCO buffers */
		 uint16_t btri_acl_mtu;      /* ACL mtu */
		 uint16_t btri_sco_mtu;      /* SCO mtu */
		 uint16_t btri_link_policy;  /* Link Policy */
		 uint16_t btri_packet_type;  /* Packet Type */
		 uint16_t btri_max_acl;      /* max ACL buffers */
		 uint16_t btri_max_sco;      /* max SCO buffers */
	     } btri;
	     struct {
		 uint8_t btrf_page0[HCI_FEATURES_SIZE]; /* basic */
		 uint8_t btrf_page1[HCI_FEATURES_SIZE]; /* extended */
	     } btrf;
	     struct bt_stats btrs;   /* unit stats */
	 } btru;
     };

     #define btr_flags	     btru.btri.btri_flags
     #define btr_bdaddr      btru.btri.btri_bdaddr
     #define btr_num_cmd     btru.btri.btri_num_cmd
     #define btr_num_acl     btru.btri.btri_num_acl
     #define btr_num_sco     btru.btri.btri_num_sco
     #define btr_acl_mtu     btru.btri.btri_acl_mtu
     #define btr_sco_mtu     btru.btri.btri_sco_mtu
     #define btr_link_policy btru.btri.btri_link_policy
     #define btr_packet_type btru.btri.btri_packet_type
     #define btr_max_acl     btru.btri.btri_max_acl
     #define btr_max_sco     btru.btri.btri_max_sco
     #define btr_features0   btru.btrf.btrf_page0
     #define btr_features1   btru.btrf.btrf_page1
     #define btr_stats	     btru.btrs

     /* btr_flags */
     #define BTF_UP		     (1<<0)  /* unit is up */
     #define BTF_RUNNING	     (1<<1)  /* unit is running */
     #define BTF_XMIT_CMD	     (1<<2)  /* transmitting CMD packets */
     #define BTF_XMIT_ACL	     (1<<3)  /* transmitting ACL packets */
     #define BTF_XMIT_SCO	     (1<<4)  /* transmitting SCO packets */
     #define BTF_INIT_BDADDR	     (1<<5)  /* waiting for bdaddr */
     #define BTF_INIT_BUFFER_SIZE    (1<<6)  /* waiting for buffer size */
     #define BTF_INIT_FEATURES	     (1<<7)  /* waiting for features */
     #define BTF_NOOP_ON_RESET	     (1<<8)  /* wait for No-op on reset */
     #define BTF_INIT_COMMANDS	     (1<<9)  /* waiting for supported commands */
     #define BTF_MASTER 	     (1<<10) /* request Master role */

     struct bt_stats {
	     uint32_t	     err_tx;
	     uint32_t	     err_rx;
	     uint32_t	     cmd_tx;
	     uint32_t	     evt_rx;
	     uint32_t	     acl_tx;
	     uint32_t	     acl_rx;
	     uint32_t	     sco_tx;
	     uint32_t	     sco_rx;
	     uint32_t	     byte_tx;
	     uint32_t	     byte_rx;
     };

     SIOCGBTINFO    Get Bluetooth device Info.	Given the device name, fill in the btreq structure including the address field for use with socket
		    addressing as above.

     SIOCGBTINFOA   Get Bluetooth device Info from Address.  Given the device address, fill in the btreq structure including the name field.

     SIOCNBTINFO    Next Bluetooth device Info.  If name field is empty, the first device will be returned.  Otherwise, the next device will be
		    returned.  Thus, you can cycle through all devices in the system.

     SIOCSBTFLAGS   Set Bluetooth device Flags.  Not all flags are settable.

     SIOCGBTFEAT    Get Bluetooth device Features.  This returns the cached basic (page 0) and extended (page 1) features.

     SIOCSBTPOLICY  Set Bluetooth device Link Policy.  Link Policy bits are defined in <netbt/hci.h>, though you can only set bits that the device
		    supports.

     SIOCSBTPTYPE   Set Bluetooth device Packet Types.	You can only set packet types that the device supports.

     SIOCGBTSTATS   Read device statistics.

     SIOCZBTSTATS   Read device statistics, and zero them.

     Only the super-user may change device configurations.

SEE ALSO

     bind(2), getsockname(2), bluetooth(3), bcsp(4), bt3c(4), btbc(4), btuart(4), options(4), ubt(4)

HISTORY

     The Bluetooth Protocol Stack was written for NetBSD 4.0 by Iain Hibbert under the sponsorship of Itronix, Inc.

BSD
								 November 20, 2010							       BSD