net/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0-only
   2 #
   3 # Network configuration
   4 #
   5
   6 menuconfig NET
   7         bool "Networking support"
   8         select NLATTR
   9         select GENERIC_NET_UTILS
  10         select BPF
  11         help
  12           Unless you really know what you are doing, you should say Y here.
  13           The reason is that some programs need kernel networking support even
  14           when running on a stand-alone machine that isn't connected to any
  15           other computer.
  16
  17           If you are upgrading from an older kernel, you
  18           should consider updating your networking tools too because changes
  19           in the kernel and the tools often go hand in hand. The tools are
  20           contained in the package net-tools, the location and version number
  21           of which are given in <file:Documentation/Changes>.
  22
  23           For a general introduction to Linux networking, it is highly
  24           recommended to read the NET-HOWTO, available from
  25           <http://www.tldp.org/docs.html#howto>.
  26
  27 if NET
  28
  29 config WANT_COMPAT_NETLINK_MESSAGES
  30         bool
  31         help
  32           This option can be selected by other options that need compat
  33           netlink messages.
  34
  35 config COMPAT_NETLINK_MESSAGES
  36         def_bool y
  37         depends on COMPAT
  38         depends on WEXT_CORE || WANT_COMPAT_NETLINK_MESSAGES
  39         help
  40           This option makes it possible to send different netlink messages
  41           to tasks depending on whether the task is a compat task or not. To
  42           achieve this, you need to set skb_shinfo(skb)->frag_list to the
  43           compat skb before sending the skb, the netlink code will sort out
  44           which message to actually pass to the task.
  45
  46           Newly written code should NEVER need this option but do
  47           compat-independent messages instead!
  48
  49 config NET_INGRESS
  50         bool
  51
  52 config NET_EGRESS
  53         bool
  54
  55 config NET_REDIRECT
  56         bool
  57
  58 config SKB_EXTENSIONS
  59         bool
  60
  61 menu "Networking options"
  62
  63 source "net/packet/Kconfig"
  64 source "net/unix/Kconfig"
  65 source "net/tls/Kconfig"
  66 source "net/xfrm/Kconfig"
  67 source "net/iucv/Kconfig"
  68 source "net/smc/Kconfig"
  69 source "net/xdp/Kconfig"
  70
  71 config INET
  72         bool "TCP/IP networking"
  73         help
  74           These are the protocols used on the Internet and on most local
  75           Ethernets. It is highly recommended to say Y here (this will enlarge
  76           your kernel by about 400 KB), since some programs (e.g. the X window
  77           system) use TCP/IP even if your machine is not connected to any
  78           other computer. You will get the so-called loopback device which
  79           allows you to ping yourself (great fun, that!).
  80
  81           For an excellent introduction to Linux networking, please read the
  82           Linux Networking HOWTO, available from
  83           <http://www.tldp.org/docs.html#howto>.
  84
  85           If you say Y here and also to "/proc file system support" and
  86           "Sysctl support" below, you can change various aspects of the
  87           behavior of the TCP/IP code by writing to the (virtual) files in
  88           /proc/sys/net/ipv4/*; the options are explained in the file
  89           <file:Documentation/networking/ip-sysctl.rst>.
  90
  91           Short answer: say Y.
  92
  93 if INET
  94 source "net/ipv4/Kconfig"
  95 source "net/ipv6/Kconfig"
  96 source "net/netlabel/Kconfig"
  97 source "net/mptcp/Kconfig"
  98
  99 endif # if INET
 100
 101 config NETWORK_SECMARK
 102         bool "Security Marking"
 103         help
 104           This enables security marking of network packets, similar
 105           to nfmark, but designated for security purposes.
 106           If you are unsure how to answer this question, answer N.
 107
 108 config NET_PTP_CLASSIFY
 109         def_bool n
 110
 111 config NETWORK_PHY_TIMESTAMPING
 112         bool "Timestamping in PHY devices"
 113         select NET_PTP_CLASSIFY
 114         help
 115           This allows timestamping of network packets by PHYs (or
 116           other MII bus snooping devices) with hardware timestamping
 117           capabilities. This option adds some overhead in the transmit
 118           and receive paths.
 119
 120           If you are unsure how to answer this question, answer N.
 121
 122 menuconfig NETFILTER
 123         bool "Network packet filtering framework (Netfilter)"
 124         help
 125           Netfilter is a framework for filtering and mangling network packets
 126           that pass through your Linux box.
 127
 128           The most common use of packet filtering is to run your Linux box as
 129           a firewall protecting a local network from the Internet. The type of
 130           firewall provided by this kernel support is called a "packet
 131           filter", which means that it can reject individual network packets
 132           based on type, source, destination etc. The other kind of firewall,
 133           a "proxy-based" one, is more secure but more intrusive and more
 134           bothersome to set up; it inspects the network traffic much more
 135           closely, modifies it and has knowledge about the higher level
 136           protocols, which a packet filter lacks. Moreover, proxy-based
 137           firewalls often require changes to the programs running on the local
 138           clients. Proxy-based firewalls don't need support by the kernel, but
 139           they are often combined with a packet filter, which only works if
 140           you say Y here.
 141
 142           You should also say Y here if you intend to use your Linux box as
 143           the gateway to the Internet for a local network of machines without
 144           globally valid IP addresses. This is called "masquerading": if one
 145           of the computers on your local network wants to send something to
 146           the outside, your box can "masquerade" as that computer, i.e. it
 147           forwards the traffic to the intended outside destination, but
 148           modifies the packets to make it look like they came from the
 149           firewall box itself. It works both ways: if the outside host
 150           replies, the Linux box will silently forward the traffic to the
 151           correct local computer. This way, the computers on your local net
 152           are completely invisible to the outside world, even though they can
 153           reach the outside and can receive replies. It is even possible to
 154           run globally visible servers from within a masqueraded local network
 155           using a mechanism called portforwarding. Masquerading is also often
 156           called NAT (Network Address Translation).
 157
 158           Another use of Netfilter is in transparent proxying: if a machine on
 159           the local network tries to connect to an outside host, your Linux
 160           box can transparently forward the traffic to a local server,
 161           typically a caching proxy server.
 162
 163           Yet another use of Netfilter is building a bridging firewall. Using
 164           a bridge with Network packet filtering enabled makes iptables "see"
 165           the bridged traffic. For filtering on the lower network and Ethernet
 166           protocols over the bridge, use ebtables (under bridge netfilter
 167           configuration).
 168
 169           Various modules exist for netfilter which replace the previous
 170           masquerading (ipmasqadm), packet filtering (ipchains), transparent
 171           proxying, and portforwarding mechanisms. Please see
 172           <file:Documentation/Changes> under "iptables" for the location of
 173           these packages.
 174
 175 if NETFILTER
 176
 177 config NETFILTER_ADVANCED
 178         bool "Advanced netfilter configuration"
 179         depends on NETFILTER
 180         default y
 181         help
 182           If you say Y here you can select between all the netfilter modules.
 183           If you say N the more unusual ones will not be shown and the
 184           basic ones needed by most people will default to 'M'.
 185
 186           If unsure, say Y.
 187
 188 config BRIDGE_NETFILTER
 189         tristate "Bridged IP/ARP packets filtering"
 190         depends on BRIDGE
 191         depends on NETFILTER && INET
 192         depends on NETFILTER_ADVANCED
 193         select NETFILTER_FAMILY_BRIDGE
 194         select SKB_EXTENSIONS
 195         help
 196           Enabling this option will let arptables resp. iptables see bridged
 197           ARP resp. IP traffic. If you want a bridging firewall, you probably
 198           want this option enabled.
 199           Enabling or disabling this option doesn't enable or disable
 200           ebtables.
 201
 202           If unsure, say N.
 203
 204 source "net/netfilter/Kconfig"
 205 source "net/ipv4/netfilter/Kconfig"
 206 source "net/ipv6/netfilter/Kconfig"
 207 source "net/decnet/netfilter/Kconfig"
 208 source "net/bridge/netfilter/Kconfig"
 209
 210 endif
 211
 212 source "net/bpfilter/Kconfig"
 213
 214 source "net/dccp/Kconfig"
 215 source "net/sctp/Kconfig"
 216 source "net/rds/Kconfig"
 217 source "net/tipc/Kconfig"
 218 source "net/atm/Kconfig"
 219 source "net/l2tp/Kconfig"
 220 source "net/802/Kconfig"
 221 source "net/bridge/Kconfig"
 222 source "net/dsa/Kconfig"
 223 source "net/8021q/Kconfig"
 224 source "net/decnet/Kconfig"
 225 source "net/llc/Kconfig"
 226 source "drivers/net/appletalk/Kconfig"
 227 source "net/x25/Kconfig"
 228 source "net/lapb/Kconfig"
 229 source "net/phonet/Kconfig"
 230 source "net/6lowpan/Kconfig"
 231 source "net/ieee802154/Kconfig"
 232 source "net/mac802154/Kconfig"
 233 source "net/sched/Kconfig"
 234 source "net/dcb/Kconfig"
 235 source "net/dns_resolver/Kconfig"
 236 source "net/batman-adv/Kconfig"
 237 source "net/openvswitch/Kconfig"
 238 source "net/vmw_vsock/Kconfig"
 239 source "net/netlink/Kconfig"
 240 source "net/mpls/Kconfig"
 241 source "net/nsh/Kconfig"
 242 source "net/hsr/Kconfig"
 243 source "net/switchdev/Kconfig"
 244 source "net/l3mdev/Kconfig"
 245 source "net/qrtr/Kconfig"
 246 source "net/ncsi/Kconfig"
 247
 248 config RPS
 249         bool
 250         depends on SMP && SYSFS
 251         default y
 252
 253 config RFS_ACCEL
 254         bool
 255         depends on RPS
 256         select CPU_RMAP
 257         default y
 258
 259 config XPS
 260         bool
 261         depends on SMP
 262         default y
 263
 264 config HWBM
 265         bool
 266
 267 config CGROUP_NET_PRIO
 268         bool "Network priority cgroup"
 269         depends on CGROUPS
 270         select SOCK_CGROUP_DATA
 271         help
 272           Cgroup subsystem for use in assigning processes to network priorities on
 273           a per-interface basis.
 274
 275 config CGROUP_NET_CLASSID
 276         bool "Network classid cgroup"
 277         depends on CGROUPS
 278         select SOCK_CGROUP_DATA
 279         help
 280           Cgroup subsystem for use as general purpose socket classid marker that is
 281           being used in cls_cgroup and for netfilter matching.
 282
 283 config NET_RX_BUSY_POLL
 284         bool
 285         default y
 286
 287 config BQL
 288         bool
 289         depends on SYSFS
 290         select DQL
 291         default y
 292
 293 config BPF_JIT
 294         bool "enable BPF Just In Time compiler"
 295         depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT
 296         depends on MODULES
 297         help
 298           Berkeley Packet Filter filtering capabilities are normally handled
 299           by an interpreter. This option allows kernel to generate a native
 300           code when filter is loaded in memory. This should speedup
 301           packet sniffing (libpcap/tcpdump).
 302
 303           Note, admin should enable this feature changing:
 304           /proc/sys/net/core/bpf_jit_enable
 305           /proc/sys/net/core/bpf_jit_harden   (optional)
 306           /proc/sys/net/core/bpf_jit_kallsyms (optional)
 307
 308 config BPF_STREAM_PARSER
 309         bool "enable BPF STREAM_PARSER"
 310         depends on INET
 311         depends on BPF_SYSCALL
 312         depends on CGROUP_BPF
 313         select STREAM_PARSER
 314         select NET_SOCK_MSG
 315         help
 316           Enabling this allows a stream parser to be used with
 317           BPF_MAP_TYPE_SOCKMAP.
 318
 319           BPF_MAP_TYPE_SOCKMAP provides a map type to use with network sockets.
 320           It can be used to enforce socket policy, implement socket redirects,
 321           etc.
 322
 323 config NET_FLOW_LIMIT
 324         bool
 325         depends on RPS
 326         default y
 327         help
 328           The network stack has to drop packets when a receive processing CPU's
 329           backlog reaches netdev_max_backlog. If a few out of many active flows
 330           generate the vast majority of load, drop their traffic earlier to
 331           maintain capacity for the other flows. This feature provides servers
 332           with many clients some protection against DoS by a single (spoofed)
 333           flow that greatly exceeds average workload.
 334
 335 menu "Network testing"
 336
 337 config NET_PKTGEN
 338         tristate "Packet Generator (USE WITH CAUTION)"
 339         depends on INET && PROC_FS
 340         help
 341           This module will inject preconfigured packets, at a configurable
 342           rate, out of a given interface.  It is used for network interface
 343           stress testing and performance analysis.  If you don't understand
 344           what was just said, you don't need it: say N.
 345
 346           Documentation on how to use the packet generator can be found
 347           at <file:Documentation/networking/pktgen.rst>.
 348
 349           To compile this code as a module, choose M here: the
 350           module will be called pktgen.
 351
 352 config NET_DROP_MONITOR
 353         tristate "Network packet drop alerting service"
 354         depends on INET && TRACEPOINTS
 355         help
 356           This feature provides an alerting service to userspace in the
 357           event that packets are discarded in the network stack.  Alerts
 358           are broadcast via netlink socket to any listening user space
 359           process.  If you don't need network drop alerts, or if you are ok
 360           just checking the various proc files and other utilities for
 361           drop statistics, say N here.
 362
 363 endmenu
 364
 365 endmenu
 366
 367 source "net/ax25/Kconfig"
 368 source "net/can/Kconfig"
 369 source "net/bluetooth/Kconfig"
 370 source "net/rxrpc/Kconfig"
 371 source "net/kcm/Kconfig"
 372 source "net/strparser/Kconfig"
 373
 374 config FIB_RULES
 375         bool
 376
 377 menuconfig WIRELESS
 378         bool "Wireless"
 379         depends on !S390
 380         default y
 381
 382 if WIRELESS
 383
 384 source "net/wireless/Kconfig"
 385 source "net/mac80211/Kconfig"
 386
 387 endif # WIRELESS
 388
 389 source "net/wimax/Kconfig"
 390
 391 source "net/rfkill/Kconfig"
 392 source "net/9p/Kconfig"
 393 source "net/caif/Kconfig"
 394 source "net/ceph/Kconfig"
 395 source "net/nfc/Kconfig"
 396 source "net/psample/Kconfig"
 397 source "net/ife/Kconfig"
 398
 399 config LWTUNNEL
 400         bool "Network light weight tunnels"
 401         help
 402           This feature provides an infrastructure to support light weight
 403           tunnels like mpls. There is no netdevice associated with a light
 404           weight tunnel endpoint. Tunnel encapsulation parameters are stored
 405           with light weight tunnel state associated with fib routes.
 406
 407 config LWTUNNEL_BPF
 408         bool "Execute BPF program as route nexthop action"
 409         depends on LWTUNNEL && INET
 410         default y if LWTUNNEL=y
 411         help
 412           Allows to run BPF programs as a nexthop action following a route
 413           lookup for incoming and outgoing packets.
 414
 415 config DST_CACHE
 416         bool
 417         default n
 418
 419 config GRO_CELLS
 420         bool
 421         default n
 422
 423 config SOCK_VALIDATE_XMIT
 424         bool
 425
 426 config NET_SOCK_MSG
 427         bool
 428         default n
 429         help
 430           The NET_SOCK_MSG provides a framework for plain sockets (e.g. TCP) or
 431           ULPs (upper layer modules, e.g. TLS) to process L7 application data
 432           with the help of BPF programs.
 433
 434 config NET_DEVLINK
 435         bool
 436         default n
 437         imply NET_DROP_MONITOR
 438
 439 config PAGE_POOL
 440         bool
 441
 442 config FAILOVER
 443         tristate "Generic failover module"
 444         help
 445           The failover module provides a generic interface for paravirtual
 446           drivers to register a netdev and a set of ops with a failover
 447           instance. The ops are used as event handlers that get called to
 448           handle netdev register/unregister/link change/name change events
 449           on slave pci ethernet devices with the same mac address as the
 450           failover netdev. This enables paravirtual drivers to use a
 451           VF as an accelerated low latency datapath. It also allows live
 452           migration of VMs with direct attached VFs by failing over to the
 453           paravirtual datapath when the VF is unplugged.
 454
 455 config ETHTOOL_NETLINK
 456         bool "Netlink interface for ethtool"
 457         default y
 458         help
 459           An alternative userspace interface for ethtool based on generic
 460           netlink. It provides better extensibility and some new features,
 461           e.g. notification messages.
 462
 463 endif   # if NET
 464
 465 # Used by archs to tell that they support BPF JIT compiler plus which flavour.
 466 # Only one of the two can be selected for a specific arch since eBPF JIT supersedes
 467 # the cBPF JIT.
 468
 469 # Classic BPF JIT (cBPF)
 470 config HAVE_CBPF_JIT
 471         bool
 472
 473 # Extended BPF JIT (eBPF)
 474 config HAVE_EBPF_JIT
 475         bool