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/decnet/netfilter/Kconfig" 208source "net/bridge/netfilter/Kconfig" 209 210endif 211 212source "net/bpfilter/Kconfig" 213 214source "net/dccp/Kconfig" 215source "net/sctp/Kconfig" 216source "net/rds/Kconfig" 217source "net/tipc/Kconfig" 218source "net/atm/Kconfig" 219source "net/l2tp/Kconfig" 220source "net/802/Kconfig" 221source "net/bridge/Kconfig" 222source "net/dsa/Kconfig" 223source "net/8021q/Kconfig" 224source "net/decnet/Kconfig" 225source "net/llc/Kconfig" 226source "drivers/net/appletalk/Kconfig" 227source "net/x25/Kconfig" 228source "net/lapb/Kconfig" 229source "net/phonet/Kconfig" 230source "net/6lowpan/Kconfig" 231source "net/ieee802154/Kconfig" 232source "net/mac802154/Kconfig" 233source "net/sched/Kconfig" 234source "net/dcb/Kconfig" 235source "net/dns_resolver/Kconfig" 236source "net/batman-adv/Kconfig" 237source "net/openvswitch/Kconfig" 238source "net/vmw_vsock/Kconfig" 239source "net/netlink/Kconfig" 240source "net/mpls/Kconfig" 241source "net/nsh/Kconfig" 242source "net/hsr/Kconfig" 243source "net/switchdev/Kconfig" 244source "net/l3mdev/Kconfig" 245source "net/qrtr/Kconfig" 246source "net/ncsi/Kconfig" 247 248config RPS 249 bool 250 depends on SMP && SYSFS 251 default y 252 253config RFS_ACCEL 254 bool 255 depends on RPS 256 select CPU_RMAP 257 default y 258 259config XPS 260 bool 261 depends on SMP 262 default y 263 264config HWBM 265 bool 266 267config 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 275config 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 283config NET_RX_BUSY_POLL 284 bool 285 default y 286 287config BQL 288 bool 289 depends on SYSFS 290 select DQL 291 default y 292 293config 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 308config 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 323config 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 335menu "Network testing" 336 337config 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 352config 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 363endmenu 364 365endmenu 366 367source "net/ax25/Kconfig" 368source "net/can/Kconfig" 369source "net/bluetooth/Kconfig" 370source "net/rxrpc/Kconfig" 371source "net/kcm/Kconfig" 372source "net/strparser/Kconfig" 373 374config FIB_RULES 375 bool 376 377menuconfig WIRELESS 378 bool "Wireless" 379 depends on !S390 380 default y 381 382if WIRELESS 383 384source "net/wireless/Kconfig" 385source "net/mac80211/Kconfig" 386 387endif # WIRELESS 388 389source "net/wimax/Kconfig" 390 391source "net/rfkill/Kconfig" 392source "net/9p/Kconfig" 393source "net/caif/Kconfig" 394source "net/ceph/Kconfig" 395source "net/nfc/Kconfig" 396source "net/psample/Kconfig" 397source "net/ife/Kconfig" 398 399config 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 407config 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 415config DST_CACHE 416 bool 417 default n 418 419config GRO_CELLS 420 bool 421 default n 422 423config SOCK_VALIDATE_XMIT 424 bool 425 426config 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 434config NET_DEVLINK 435 bool 436 default n 437 imply NET_DROP_MONITOR 438 439config PAGE_POOL 440 bool 441 442config 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 455config ETHTOOL_NETLINK 456 bool "Netlink interface for ethtool" 457 default y 458 depends on PHYLIB=y || PHYLIB=n 459 help 460 An alternative userspace interface for ethtool based on generic 461 netlink. It provides better extensibility and some new features, 462 e.g. notification messages. 463 464endif # if NET 465 466# Used by archs to tell that they support BPF JIT compiler plus which flavour. 467# Only one of the two can be selected for a specific arch since eBPF JIT supersedes 468# the cBPF JIT. 469 470# Classic BPF JIT (cBPF) 471config HAVE_CBPF_JIT 472 bool 473 474# Extended BPF JIT (eBPF) 475config HAVE_EBPF_JIT 476 bool 477