1# SPDX-License-Identifier: GPL-2.0-only 2# 3# Network configuration 4# 5 6menuconfig 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 27if NET 28 29config WANT_COMPAT_NETLINK_MESSAGES 30 bool 31 help 32 This option can be selected by other options that need compat 33 netlink messages. 34 35config 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 49config NET_INGRESS 50 bool 51 52config NET_EGRESS 53 bool 54 55config NET_REDIRECT 56 bool 57 58config SKB_EXTENSIONS 59 bool 60 61menu "Networking options" 62 63source "net/packet/Kconfig" 64source "net/unix/Kconfig" 65source "net/tls/Kconfig" 66source "net/xfrm/Kconfig" 67source "net/iucv/Kconfig" 68source "net/smc/Kconfig" 69source "net/xdp/Kconfig" 70 71config 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 93if INET 94source "net/ipv4/Kconfig" 95source "net/ipv6/Kconfig" 96source "net/netlabel/Kconfig" 97source "net/mptcp/Kconfig" 98 99endif # if INET 100 101config 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 108config NET_PTP_CLASSIFY 109 def_bool n 110 111config 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 122menuconfig 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 175if NETFILTER 176 177config 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 188config 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 204source "net/netfilter/Kconfig" 205source "net/ipv4/netfilter/Kconfig" 206source "net/ipv6/netfilter/Kconfig" 207source "net/bridge/netfilter/Kconfig" 208 209endif 210 211source "net/bpfilter/Kconfig" 212 213source "net/dccp/Kconfig" 214source "net/sctp/Kconfig" 215source "net/rds/Kconfig" 216source "net/tipc/Kconfig" 217source "net/atm/Kconfig" 218source "net/l2tp/Kconfig" 219source "net/802/Kconfig" 220source "net/bridge/Kconfig" 221source "net/dsa/Kconfig" 222source "net/8021q/Kconfig" 223source "net/llc/Kconfig" 224source "drivers/net/appletalk/Kconfig" 225source "net/x25/Kconfig" 226source "net/lapb/Kconfig" 227source "net/phonet/Kconfig" 228source "net/6lowpan/Kconfig" 229source "net/ieee802154/Kconfig" 230source "net/mac802154/Kconfig" 231source "net/sched/Kconfig" 232source "net/dcb/Kconfig" 233source "net/dns_resolver/Kconfig" 234source "net/batman-adv/Kconfig" 235source "net/openvswitch/Kconfig" 236source "net/vmw_vsock/Kconfig" 237source "net/netlink/Kconfig" 238source "net/mpls/Kconfig" 239source "net/nsh/Kconfig" 240source "net/hsr/Kconfig" 241source "net/switchdev/Kconfig" 242source "net/l3mdev/Kconfig" 243source "net/qrtr/Kconfig" 244source "net/ncsi/Kconfig" 245 246config PCPU_DEV_REFCNT 247 bool "Use percpu variables to maintain network device refcount" 248 depends on SMP 249 default y 250 help 251 network device refcount are using per cpu variables if this option is set. 252 This can be forced to N to detect underflows (with a performance drop). 253 254config RPS 255 bool 256 depends on SMP && SYSFS 257 default y 258 259config RFS_ACCEL 260 bool 261 depends on RPS 262 select CPU_RMAP 263 default y 264 265config SOCK_RX_QUEUE_MAPPING 266 bool 267 268config XPS 269 bool 270 depends on SMP 271 select SOCK_RX_QUEUE_MAPPING 272 default y 273 274config HWBM 275 bool 276 277config CGROUP_NET_PRIO 278 bool "Network priority cgroup" 279 depends on CGROUPS 280 select SOCK_CGROUP_DATA 281 help 282 Cgroup subsystem for use in assigning processes to network priorities on 283 a per-interface basis. 284 285config CGROUP_NET_CLASSID 286 bool "Network classid cgroup" 287 depends on CGROUPS 288 select SOCK_CGROUP_DATA 289 help 290 Cgroup subsystem for use as general purpose socket classid marker that is 291 being used in cls_cgroup and for netfilter matching. 292 293config NET_RX_BUSY_POLL 294 bool 295 default y if !PREEMPT_RT 296 297config BQL 298 bool 299 depends on SYSFS 300 select DQL 301 default y 302 303config BPF_STREAM_PARSER 304 bool "enable BPF STREAM_PARSER" 305 depends on INET 306 depends on BPF_SYSCALL 307 depends on CGROUP_BPF 308 select STREAM_PARSER 309 select NET_SOCK_MSG 310 help 311 Enabling this allows a TCP stream parser to be used with 312 BPF_MAP_TYPE_SOCKMAP. 313 314config NET_FLOW_LIMIT 315 bool 316 depends on RPS 317 default y 318 help 319 The network stack has to drop packets when a receive processing CPU's 320 backlog reaches netdev_max_backlog. If a few out of many active flows 321 generate the vast majority of load, drop their traffic earlier to 322 maintain capacity for the other flows. This feature provides servers 323 with many clients some protection against DoS by a single (spoofed) 324 flow that greatly exceeds average workload. 325 326menu "Network testing" 327 328config NET_PKTGEN 329 tristate "Packet Generator (USE WITH CAUTION)" 330 depends on INET && PROC_FS 331 help 332 This module will inject preconfigured packets, at a configurable 333 rate, out of a given interface. It is used for network interface 334 stress testing and performance analysis. If you don't understand 335 what was just said, you don't need it: say N. 336 337 Documentation on how to use the packet generator can be found 338 at <file:Documentation/networking/pktgen.rst>. 339 340 To compile this code as a module, choose M here: the 341 module will be called pktgen. 342 343config NET_DROP_MONITOR 344 tristate "Network packet drop alerting service" 345 depends on INET && TRACEPOINTS 346 help 347 This feature provides an alerting service to userspace in the 348 event that packets are discarded in the network stack. Alerts 349 are broadcast via netlink socket to any listening user space 350 process. If you don't need network drop alerts, or if you are ok 351 just checking the various proc files and other utilities for 352 drop statistics, say N here. 353 354endmenu 355 356endmenu 357 358source "net/ax25/Kconfig" 359source "net/can/Kconfig" 360source "net/bluetooth/Kconfig" 361source "net/rxrpc/Kconfig" 362source "net/kcm/Kconfig" 363source "net/strparser/Kconfig" 364source "net/mctp/Kconfig" 365 366config FIB_RULES 367 bool 368 369menuconfig WIRELESS 370 bool "Wireless" 371 depends on !S390 372 default y 373 374if WIRELESS 375 376source "net/wireless/Kconfig" 377source "net/mac80211/Kconfig" 378 379endif # WIRELESS 380 381source "net/rfkill/Kconfig" 382source "net/9p/Kconfig" 383source "net/caif/Kconfig" 384source "net/ceph/Kconfig" 385source "net/nfc/Kconfig" 386source "net/psample/Kconfig" 387source "net/ife/Kconfig" 388 389config LWTUNNEL 390 bool "Network light weight tunnels" 391 help 392 This feature provides an infrastructure to support light weight 393 tunnels like mpls. There is no netdevice associated with a light 394 weight tunnel endpoint. Tunnel encapsulation parameters are stored 395 with light weight tunnel state associated with fib routes. 396 397config LWTUNNEL_BPF 398 bool "Execute BPF program as route nexthop action" 399 depends on LWTUNNEL && INET 400 default y if LWTUNNEL=y 401 help 402 Allows to run BPF programs as a nexthop action following a route 403 lookup for incoming and outgoing packets. 404 405config DST_CACHE 406 bool 407 default n 408 409config GRO_CELLS 410 bool 411 default n 412 413config SOCK_VALIDATE_XMIT 414 bool 415 416config NET_SELFTESTS 417 def_tristate PHYLIB 418 depends on PHYLIB && INET 419 420config NET_SOCK_MSG 421 bool 422 default n 423 help 424 The NET_SOCK_MSG provides a framework for plain sockets (e.g. TCP) or 425 ULPs (upper layer modules, e.g. TLS) to process L7 application data 426 with the help of BPF programs. 427 428config NET_DEVLINK 429 bool 430 default n 431 432config PAGE_POOL 433 bool 434 435config PAGE_POOL_STATS 436 default n 437 bool "Page pool stats" 438 depends on PAGE_POOL 439 help 440 Enable page pool statistics to track page allocation and recycling 441 in page pools. This option incurs additional CPU cost in allocation 442 and recycle paths and additional memory cost to store the statistics. 443 These statistics are only available if this option is enabled and if 444 the driver using the page pool supports exporting this data. 445 446 If unsure, say N. 447 448config FAILOVER 449 tristate "Generic failover module" 450 help 451 The failover module provides a generic interface for paravirtual 452 drivers to register a netdev and a set of ops with a failover 453 instance. The ops are used as event handlers that get called to 454 handle netdev register/unregister/link change/name change events 455 on slave pci ethernet devices with the same mac address as the 456 failover netdev. This enables paravirtual drivers to use a 457 VF as an accelerated low latency datapath. It also allows live 458 migration of VMs with direct attached VFs by failing over to the 459 paravirtual datapath when the VF is unplugged. 460 461config ETHTOOL_NETLINK 462 bool "Netlink interface for ethtool" 463 default y 464 help 465 An alternative userspace interface for ethtool based on generic 466 netlink. It provides better extensibility and some new features, 467 e.g. notification messages. 468 469config NETDEV_ADDR_LIST_TEST 470 tristate "Unit tests for device address list" 471 default KUNIT_ALL_TESTS 472 depends on KUNIT 473 474endif # if NET 475