nuttx/net/Kconfig

#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#

config ARCH_HAVE_NET
	bool
	default n

config ARCH_HAVE_PHY
	bool
	default n

config NET
	bool "Networking support"
	default n
	select ARCH_HAVE_NET
	---help---
		Enable or disable all network features

if NET

config NET_PROMISCUOUS
	bool "Promiscuous mode"
	default n
	---help---
		Force the Ethernet driver to operate in promiscuous mode (if supported
		by the Ethernet driver).

menu "Driver buffer configuration"

config NET_ETH_MTU
	int "Ethernet packet buffer size (MTU)"
	default 1294 if NET_IPv6
	default 590 if !NET_IPv6
	depends on NET_ETHERNET
	range 590 1518
	---help---
		Packet buffer size.  This size includes the TCP/UDP payload plus the
		size of TCP/UDP header, the IP header, and the Ethernet header.
		This value is normally referred to as the MTU (Maximum Transmission
		Unit); the payload is the MSS (Maximum Segment Size).

		IPv4 hosts are required to be able to handle an MSS of at least
		536 octets, resulting in a minimum buffer size of 536+20+20+14 =
		590.

		IPv6 hosts are required to be able to handle an MSS of 1220 octets,
		resulting in a minimum buffer size of of 1220+20+40+14 = 1294

config NET_ETH_TCP_RECVWNDO
	int "Ethernet TCP receive window size"
	default 1220 if NET_IPv6
	default 536 if !NET_IPv6
	depends on NET_ETHERNET && NET_TCP
	---help---
		The size of the advertised receiver's window.   Should be set low
		(i.e., to the size of the MSS) if the application is slow to process
		incoming data, or high (32768 bytes) if the application processes
		data quickly.

config NET_SLIP_MTU
	int # "SLIP packet buffer size (MTU)"
	default 296
	depends on NET_SLIP
	range 296 1518
	---help---
		Provides the size of the SLIP packet buffers.  This size includes
		the TCP/UDP payload plus the size of TCP/UDP header and the IP header.
		This value is normally referred to as the MTU (Maximum Transmission Unit);
		the payload payload is the MSS (Maximum Segment Size).

		SLIP is required to support at lest 256+20+20 = 296.  Values other than
		296 are not recommended.

		The Linux slip module hard-codes its MTU size to 296 (40 bytes for
		the IP+TPC headers plus 256 bytes of data).  So you might as well
		set CONFIG_NET_SLIP_MTU to 296 as well.

		There may be an issue with this setting, however.  I see that Linux
		uses a MTU of 296 and window of 256, but actually only sends 168
		bytes of data: 40 + 128.  I believe that is to allow for the 2x
		worst cast packet expansion.  Ideally we would like to advertise the
		256 MSS, but restrict transfers to 128 bytes (possibly by modifying
		the MSS value in the TCP connection structure).


config NET_SLIP_TCP_RECVWNDO
	int "SLIP TCP receive window size"
	default 256
	depends on NET_SLIP && NET_TCP
	---help---
		The size of the advertised receiver's window.   Should be set low
		(i.e., to the size of the MSS) if the application is slow to process
		incoming data, or high (32768 bytes) if the application processes
		data quickly.

config NET_GUARDSIZE
	int "Driver I/O guard size"
	default 2
	---help---
		Network drivers often receive packets with garbage at the end and
		are longer than the size of packet in the TCP header.  The following
		"fudge" factor increases the size of the I/O buffering by a small
		amount to allocate slightly oversize packets.  After receipt, the
		packet size will be chopped down to the size indicated in the TCP
		header.

endmenu # Driver buffer configuration

menu "Data link support"

config NET_MULTILINK
	bool
	default n

config NET_USER_DEVFMT
	bool "User provided devfmt"
	default n
	depends on EXPERIMENTAL
	---help---
		netdev_register will get devfmt form d_ifname if it is initialized.

config NET_ETHERNET
	bool "Ethernet support"
	default y if !NET_SLIP
	default n if NET_SLIP
	select NETDEV_MULTINIC if NET_LOOPBACK || NET_SLIP || NET_TUN
	select NET_MULTILINK if NET_LOOPBACK || NET_SLIP || NET_TUN
	---help---
		If NET_SLIP is not selected, then Ethernet will be used (there is
		no need to define anything special in the configuration file to use
		Ethernet -- it is the default).

config NET_LOOPBACK
	bool "Local loopback"
	default n
	select NETDEV_MULTINIC if NET_ETHERNET || NET_SLIP || NET_TUN
	select NET_MULTILINK if NET_ETHERNET || NET_SLIP || NET_TUN
	---help---
		Add support for the local network loopback device, lo.

config NET_SLIP
	bool "SLIP support"
	default n
	select NETDEV_MULTINIC if NET_ETHERNET || NET_LOOPBACK || NET_TUN
	select NET_MULTILINK if NET_ETHERNET || NET_LOOPBACK || NET_TUN
	---help---
		Enables building of the SLIP driver. SLIP requires
		at least one IP protocol selected.

		SLIP supports point-to-point IP communications over a serial port.
		The default data link layer for network layer is Ethernet. If
		NET_SLIP is defined in the NuttX configuration file, then SLIP will
		be supported.  The basic differences between the SLIP and Ethernet
		configurations is that when SLIP is selected:

			* The link level header (that comes before the IP header) is omitted.
			* All MAC address processing is suppressed.
			* ARP is disabled.

		If NET_SLIP is not selected, then Ethernet will be used (there is
		no need to define anything special in the configuration file to use
		Ethernet -- it is the default).

if NET_SLIP

config SLIP_NINTERFACES
	int "Number of SLIP interfaces"
	default 1
	---help---
		Selects the number of physical SLIP
		interfaces to support.
		Default: 1

config SLIP_STACKSIZE
	int "SLIP stack size"
	default 2048
	---help---
		Select the stack size of the SLIP RX and TX tasks.  Default: 2048

config SLIP_DEFPRIO
	int "SLIP priority"
	default 128
	---help---
		The priority of the SLIP RX and TX tasks. Default: 128

endif # NET_SLIP

config NET_TUN
	bool "TUN Virtual Network Device support"
	default n
	select NETDEV_MULTINIC if NET_ETHERNET || NET_LOOPBACK || NET_SLIP
	select NET_MULTILINK if NET_ETHERNET || NET_LOOPBACK || NET_SLIP
	select ARCH_HAVE_NETDEV_STATISTICS

if NET_TUN

config TUN_NINTERFACES
	int "Number of TUN interfaces"
	default 1
	range 1 8
	---help---
		Selects the number of TUN
		interfaces to support.
		Default: 1

config NET_TUN_MTU
	int "TUN packet buffer size (MTU)"
	default 296
	range 296 1518

config NET_TUN_TCP_RECVWNDO
	int "TUN TCP receive window size"
	default 256
	depends on NET_TCP

choice
	prompt "Work queue"
	default LOOPBACK_LPWORK if SCHED_LPWORK
	default TUN_HPWORK if !SCHED_LPWORK && SCHED_HPWORK
	depends on SCHED_WORKQUEUE
	---help---
		Work queue support is required to use the TUN driver.  If the
		low priority work queue is available, then it should be used by the
		TUN driver.

config TUN_HPWORK
	bool "High priority"
	depends on SCHED_HPWORK

config TUN_LPWORK
	bool "Low priority"
	depends on SCHED_LPWORK

endchoice # Work queue
endif # NET_TUN

endmenu # Data link support

source "net/netdev/Kconfig"

menu "Internet Protocol Selection"

config NET_IPv4
	bool "IPv4"
	default y
	---help---
		Build in support for IPv4.

menuconfig NET_IPv6
	bool "IPv6"
	default n
	---help---
		Build in support for IPv6.

source "net/neighbor/Kconfig"
source "net/6lowpan/Kconfig"

endmenu # Internet Protocol Selection

source "net/socket/Kconfig"
source "net/pkt/Kconfig"
source "net/local/Kconfig"
source "net/tcp/Kconfig"
source "net/udp/Kconfig"
source "net/icmp/Kconfig"
source "net/icmpv6/Kconfig"
source "net/igmp/Kconfig"
source "net/arp/Kconfig"
source "net/loopback/Kconfig"
source "net/iob/Kconfig"
source "net/procfs/Kconfig"
source "net/utils/Kconfig"

config NET_STATISTICS
	bool "Collect network statistics"
	default n
	---help---
		Network layer statistics on or off

source "net/route/Kconfig"

config NET_HOSTNAME
	string "Host name for current machine"
	default ""
	---help---
		A unique name to identify device on the network

endif # NET