zephyr/subsys/net/lib/sockets/Kconfig

# BSD Sockets compatible API

# Copyright (c) 2017 Linaro Limited.
# SPDX-License-Identifier: Apache-2.0

menuconfig NET_SOCKETS
	bool "BSD Sockets compatible API"
	select ZVFS
	select ZVFS_POLL
	select ZVFS_SELECT
	help
	  Provide BSD Sockets like API on top of native Zephyr networking API.

if NET_SOCKETS

config NET_SOCKETS_PRIORITY_DEFAULT
	int "Default processing priority for sockets"
	default 50
	help
	  Default processing priority for socket implementations. This defines
	  the order of processing of particular socket implementations when
	  creating a new socket, lower value indicate earlier processing. This
	  allows to for instance prioritize offloaded socket processing during
	  socket creation over the native one, or vice versa.

config NET_SOCKETS_POLL_MAX
	int "Max number of supported poll() entries [DEPRECATED]"
	default 0
	help
	  This option is deprecated.
	  Please use CONFIG_ZVFS_POLL_MAX instead.

config NET_SOCKETS_CONNECT_TIMEOUT
	int "Timeout value in milliseconds to CONNECT"
	default 3000
	range 0 60000
	help
	  This variable specifies time in milliseconds after connect()
	  API call will timeout if we have not received SYN-ACK from
	  peer.

config NET_SOCKETS_DNS_TIMEOUT
	int "Timeout value in milliseconds for DNS queries"
	default 2000
	range 1000 300000
	depends on DNS_RESOLVER
	help
	  This variable specifies time in milliseconds after which DNS
	  query is considered timeout. Minimum timeout is 1 second and
	  maximum timeout is 5 min. If the value is higher than
	  CONFIG_NET_SOCKETS_DNS_BACKOFF_INTERVAL, then we try multiple
	  times with exponential backoff until the timeout is reached.

config NET_SOCKETS_DNS_BACKOFF_INTERVAL
	int "Backoff interval for the DNS timeout"
	default 5000
	range 1000 300000
	depends on DNS_RESOLVER
	help
	  This variable is related to the DNS timeout. If the DNS timeout is
	  smaller than this value, then this value is ignored. If the timeout
	  is larger, then this variable specifies time in milliseconds after
	  which DNS query is re-tried. If there is no reply, the backoff
	  interval is doubled and query is retried.
	  Example:
	     The CONFIG_NET_SOCKETS_DNS_TIMEOUT is set to 17000 (17 secs).
	     This value is 5000 (5 sec). If there is no reply from DNS server
	     within 5 secs, a 2nd query is done with timeout set to 10 sec (5 * 2).
	     If no reply is received, a 3rd query is done after 15 sec (5 + 5 * 2),
	     and the timeout is set to 2 sec so that the total timeout is 17 seconds.

config NET_SOCKET_MAX_SEND_WAIT
	int "Max time in milliseconds waiting for a send command"
	default 10000
	help
	  The maximum time a socket is waiting for a blocked connection before
	  returning an ENOBUFS error.

config NET_SOCKETS_SERVICE
	bool "Socket service support"
	select EVENTFD
	help
	  The socket service can monitor multiple sockets and save memory
	  by only having one thread listening socket data. If data is received
	  in the monitored socket, a user supplied work is called.
	  Note that you need to set CONFIG_ZVFS_POLL_MAX high enough
	  so that enough sockets entries can be serviced. This depends on
	  system needs as multiple services can be activated at the same time
	  depending on network configuration.

config NET_SOCKETS_SERVICE_THREAD_PRIO
	int "Priority of the socket service dispatcher thread"
	default NUM_PREEMPT_PRIORITIES
	depends on NET_SOCKETS_SERVICE
	help
	  Set the priority of the socket service dispatcher thread. This handler
	  polls the sockets and calls the user supplied callback directly.

	  Note that >= 0 value means preemptive thread priority, the lowest
	  value is NUM_PREEMPT_PRIORITIES.
	  Highest preemptive thread priority is 0.
	  Lowest cooperative thread priority is -1.
	  Highest cooperative thread priority is -NUM_COOP_PRIORITIES.

config NET_SOCKETS_SERVICE_STACK_SIZE
	int "Stack size for the thread handling socket services"
	default 2400 if NET_DHCPV4_SERVER
	default 1400 if MDNS_RESPONDER
	default 1200
	depends on NET_SOCKETS_SERVICE
	help
	  Set the internal stack size for the thread that polls sockets.

config NET_SOCKETS_SOCKOPT_TLS
	bool "TCP TLS socket option support"
	imply TLS_CREDENTIALS
	select MBEDTLS if NET_NATIVE
	imply MBEDTLS_TLS_VERSION_1_2 if !NET_L2_OPENTHREAD
	imply MBEDTLS_MD if !NET_L2_OPENTHREAD
	imply MBEDTLS_RSA_C if !NET_L2_OPENTHREAD
	imply MBEDTLS_PKCS1_V15 if !NET_L2_OPENTHREAD
	imply MBEDTLS_PKCS1_V21 if !NET_L2_OPENTHREAD
	imply MBEDTLS_KEY_EXCHANGE_RSA_ENABLED if !NET_L2_OPENTHREAD
	imply MBEDTLS_CIPHER_AES_ENABLED if !NET_L2_OPENTHREAD
	imply PSA_WANT_KEY_TYPE_AES if !NET_L2_OPENTHREAD && PSA_CRYPTO_CLIENT
	imply PSA_WANT_ALG_CBC_NO_PADDING if !NET_L2_OPENTHREAD && PSA_CRYPTO_CLIENT
	help
	  Enable TLS socket option support which automatically establishes
	  a TLS connection to the remote host.

config NET_SOCKETS_TLS_PRIORITY
	int "Default processing priority for TLS sockets"
	default 45
	help
	  Processing priority for TLS sockets. Should be lower than
	  NET_SOCKETS_PRIORITY_DEFAULT in order to be processed correctly.

config NET_SOCKETS_TLS_SET_MAX_FRAGMENT_LENGTH
	bool "Set Maximum Fragment Length (MFL)"
	default y
	help
	  Call mbedtls_ssl_conf_max_frag_len() on created TLS context
	  configuration, so that Maximum Fragment Length (MFL) will be sent to
	  peer using RFC 6066 max_fragment_length extension.

	  Maximum Fragment Length (MFL) value is automatically chosen based on
	  MBEDTLS_SSL_OUT_CONTENT_LEN and MBEDTLS_SSL_IN_CONTENT_LEN mbed TLS
	  macros (which are configured by CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN in
	  case of default mbed TLS config). With DTLS, MFL value may be further
	  limited with NET_SOCKETS_DTLS_MAX_FRAGMENT_LENGTH.

	  This is mostly useful for TLS client side to tell TLS server what is
	  the maximum supported receive record length.

config NET_SOCKETS_ENABLE_DTLS
	bool "DTLS socket support"
	depends on NET_SOCKETS_SOCKOPT_TLS
	select MBEDTLS_DTLS if NET_NATIVE
	help
	  Enable DTLS socket support. By default only TLS over TCP is supported.

config NET_SOCKETS_DTLS_TIMEOUT
	int "Timeout value in milliseconds for DTLS connection"
	default 5000
	depends on NET_SOCKETS_ENABLE_DTLS
	help
	  This variable specifies time in milliseconds after which DTLS
	  connection is considered dead by TLS server and DTLS resources are
	  freed. This is needed to prevent situation when DTLS client shuts down
	  without closing connection gracefully, which can prevent other peers
	  from connecting. Value of 0 indicates no timeout - resources will be
	  freed only when connection is gracefully closed by peer sending TLS
	  notification or socket is closed.

config NET_SOCKETS_DTLS_MAX_FRAGMENT_LENGTH
	int "Maximum DTLS fragment size in bytes"
	default 1024
	range 512 4096
	depends on NET_SOCKETS_ENABLE_DTLS
	depends on NET_SOCKETS_TLS_SET_MAX_FRAGMENT_LENGTH
	help
	  This variable specifies the Maximum Fragment Length (MFL) value to
	  be used with DTLS connection when MBEDTLS_SSL_OUT_CONTENT_LEN and
	  MBEDTLS_SSL_IN_CONTENT_LEN are set to larger values (for TLS).

	  With DTLS the MFL should be kept under the network MTU, to avoid
	  IP fragmentation.

config NET_SOCKETS_DTLS_SENDMSG_BUF_SIZE
	int "Intermediate buffer size for DTLS sendmsg()"
	depends on NET_SOCKETS_ENABLE_DTLS
	range 0 $(UINT16_MAX)
	default 0
	help
	  Size of the intermediate buffer for DTLS sendmsg() function. The
	  intermediate buffer is needed, as sendmsg() for DGRAM is expected to
	  send all of the data in a single datagram, therefore all data provided
	  in msghdr structure need to be linearized before passing to mbed TLS.
	  The buffer size can be set to 0, in that case data linearizing for
	  DTLS sockets is disabled. In result, sendmsg() will only accept msghdr
	  with a single non-empty iov buffer.

config NET_SOCKETS_TLS_MAX_CONTEXTS
	int "Maximum number of TLS/DTLS contexts"
	default 1
	depends on NET_SOCKETS_SOCKOPT_TLS
	help
	  "This variable specifies maximum number of TLS/DTLS contexts that can
	   be allocated at the same time."

config NET_SOCKETS_TLS_MAX_CREDENTIALS
	int "Maximum number of TLS/DTLS credentials per socket"
	default 4
	depends on NET_SOCKETS_SOCKOPT_TLS
	help
	  This variable sets maximum number of TLS/DTLS credentials that can be
	  used with a specific socket.

config NET_SOCKETS_TLS_MAX_CIPHERSUITES
	int "Maximum number of TLS/DTLS ciphersuites per socket"
	default 4
	depends on NET_SOCKETS_SOCKOPT_TLS
	help
	  This variable sets maximum number of TLS/DTLS ciphersuites that can
	  be used with specific socket, if set explicitly by socket option.
	  By default, all ciphersuites that are available in the system are
	  available to the socket.

config NET_SOCKETS_TLS_MAX_APP_PROTOCOLS
	int "Maximum number of supported application layer protocols"
	default 2
	depends on NET_SOCKETS_SOCKOPT_TLS && MBEDTLS_SSL_ALPN
	help
	  This variable sets maximum number of supported application layer
	  protocols over TLS/DTLS that can be set explicitly by a socket option.
	  By default, no supported application layer protocol is set.

config NET_SOCKETS_TLS_MAX_CLIENT_SESSION_COUNT
	  int "Maximum number of stored client TLS/DTLS sessions"
	  default 1
	  depends on NET_SOCKETS_SOCKOPT_TLS
	  help
	    This variable specifies maximum number of stored TLS/DTLS sessions,
	    used for TLS/DTLS session resumption.

config NET_SOCKETS_OFFLOAD
	bool "Offload Socket APIs"
	help
	  Enables direct offloading of socket operations to dedicated TCP/IP
	  hardware.
	  This feature is intended to save resources by bypassing the Zephyr
	  TCP/IP stack in the case where there is only one network interface
	  required in the system, providing full BSD socket offload capability.
	  As a result, it bypasses any potential IP routing that Zephyr might
	  provide between multiple network interfaces.
	  See NET_OFFLOAD for a more deeply integrated approach which offloads
	  from the net_context() API within the Zephyr IP stack.

config NET_SOCKETS_OFFLOAD_PRIORITY
	int "Default processing priority for offloaded sockets"
	default 40
	help
	  Processing priority for offloaded sockets.

	  If native TLS is enabled, lower value than NET_SOCKETS_TLS_PRIORITY
	  means that TLS will be offloaded as well (if supported by offloaded
	  socket implementation). Higher value than NET_SOCKETS_TLS_PRIORITY
	  means that native TLS will be used.

config NET_SOCKETS_OFFLOAD_DISPATCHER
	bool "Intermediate socket offloading layer"
	depends on NET_SOCKETS_OFFLOAD
	help
	  If enabled, an intermediate socket offloading layer is included
	  (called socket dispatcher), allowing to select an offloaded network
	  interface and thus socket implementation with SO_BINDTODEVICE socket
	  option. This can be useful, when multiple offloaded sockets
	  implementations are available in the system, allowing to easily bind
	  a socket to a particular implementation.

config NET_SOCKETS_OFFLOAD_DISPATCHER_CONTEXT_MAX
	int "Maximum number of dispatcher sockets created"
	default 4
	depends on NET_SOCKETS_OFFLOAD_DISPATCHER
	help
	  Maximum number of dispatcher sockets created at a time. Note, that
	  only sockets that has not been dispatched yet count into the limit.
	  After a proper socket has been created for a given file descriptor,
	  the dispatcher context is released and can be reused.

config NET_SOCKETS_PACKET
	bool "Packet socket support"
	select NET_CONNECTION_SOCKETS
	help
	  This is an initial version of packet socket support (special type
	  raw socket). Packets are passed to and from the device driver
	  without any changes in the packet headers. It's API caller
	  responsibility to provide all the headers (e.g L2, L3 and so on)
	  while sending. While receiving, packets (including all the headers)
	  will be fed to sockets unchanged as provided by the driver.

config NET_SOCKETS_PACKET_DGRAM
	bool "Packet socket SOCK_DGRAM support"
	depends on NET_SOCKETS_PACKET
	default y
	help
	  For AF_PACKET sockets with SOCK_DGRAM type, the L2 header
	  is removed before the packet is passed to the user.  Packets sent
	  through a SOCK_DGRAM packet socket get a suitable L2 header based
	  on the information in the sockaddr_ll destination address before
	  they are queued.

config NET_SOCKETS_INET_RAW
	bool "AF_INET/AF_INET6 and SOCK_RAW sockets support"
	depends on NET_NATIVE_IP
	help
	  Support SOCK_RAW socket type for AF_INET/AF_INET6 sockets. This allows
	  to receive raw IP datagrams before further processing takes place.

config NET_SOCKETS_CAN
	bool "Socket CAN support [EXPERIMENTAL]"
	select NET_L2_CANBUS_RAW
	select NET_CONNECTION_SOCKETS
	select EXPERIMENTAL
	help
	  The value depends on your network needs.

config NET_SOCKETS_CAN_RECEIVERS
	int "How many simultaneous SocketCAN receivers are allowed"
	default 1
	depends on NET_SOCKETS_CAN
	help
	  The value tells how many sockets can receive data from same
	  Socket-CAN interface.

config NET_SOCKETPAIR
	bool "Support for socketpair"
	help
	  Communicate over a pair of connected, unnamed UNIX domain sockets.

if NET_SOCKETPAIR

config NET_SOCKETPAIR_BUFFER_SIZE
	int "Size of the intermediate buffer, in bytes"
	default 1024 if WIFI_NM_WPA_SUPPLICANT
	default 64
	range 1 4096
	help
	  Buffer size for socketpair(2)

choice NET_SOCKETPAIR_ALLOCATION_STRATEGY
	prompt "Memory management for socketpair"
	default NET_SOCKETPAIR_HEAP if KERNEL_MEM_POOL

config NET_SOCKETPAIR_STATIC
	bool "Pre-allocate memory statically"

config NET_SOCKETPAIR_HEAP
	bool "Use heap for allocating socketpairs"

endchoice

if NET_SOCKETPAIR_STATIC

config NET_SOCKETPAIR_MAX
	int "How many socketpairs to pre-allocate"
	default 6 if WIFI_NM_HOSTAPD_AP
	default 4 if WIFI_NM_WPA_SUPPLICANT
	default 1

endif # NET_SOCKETPAIR_STATIC

if NET_SOCKETPAIR_HEAP

config HEAP_MEM_POOL_ADD_SIZE_SOCKETPAIR
	int
	default 9136 if WIFI_NM_HOSTAPD_AP
	default 6852 if WIFI_NM_WPA_SUPPLICANT
	default 296

endif # NET_SOCKETPAIR_HEAP

endif # NET_SOCKETPAIR

config NET_SOCKETS_NET_MGMT
	bool "Network management socket support [EXPERIMENTAL]"
	depends on NET_MGMT_EVENT
	select NET_MGMT_EVENT_INFO
	select EXPERIMENTAL
	help
	  Select this if you want to use socket API to get network
	  managements events to your application.
	  Note, that the thread using net_mgmt sockets should have at least
	  the same priority as the thread processing network events (see
	  CONFIG_NET_MGMT_EVENT_WORKER), otherwise in case of event bursts some
	  events may be lost.

config NET_SOCKETS_NET_MGMT_MAX_LISTENERS
	int "Max number of sockets to listen"
	default 1
	depends on NET_SOCKETS_NET_MGMT
	help
	  This sets the maximum number of net_mgmt sockets that can
	  be set by the socket interface. So if you have two separate
	  sockets that are used for listening events, you need to set
	  this to two.

module = NET_SOCKETS
module-dep = NET_LOG
module-str = Log level for BSD sockets compatible API calls
module-help = Enables logging for sockets code.
source "subsys/net/Kconfig.template.log_config.net"

config NET_SOCKETS_OBJ_CORE
	bool "Object core socket support [EXPERIMENTAL]"
	depends on OBJ_CORE
	select OBJ_CORE_STATS
	select EXPERIMENTAL
	help
	  Select this if you want to use object core with socket API to get
	  network socket information and statistics via object core.
	  The net-shell "net sockets" command will use this functionality
	  to show the socket information.

endif # NET_SOCKETS