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