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 SKB_EXTENSIONS 56 bool 57 58menu "Networking options" 59 60source "net/packet/Kconfig" 61source "net/unix/Kconfig" 62source "net/tls/Kconfig" 63source "net/xfrm/Kconfig" 64source "net/iucv/Kconfig" 65source "net/smc/Kconfig" 66source "net/xdp/Kconfig" 67 68config 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 90if INET 91source "net/ipv4/Kconfig" 92source "net/ipv6/Kconfig" 93source "net/netlabel/Kconfig" 94 95endif # if INET 96 97config 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 104config NET_PTP_CLASSIFY 105 def_bool n 106 107config 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 117menuconfig 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 170if NETFILTER 171 172config 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 183config 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 200source "net/netfilter/Kconfig" 201source "net/ipv4/netfilter/Kconfig" 202source "net/ipv6/netfilter/Kconfig" 203source "net/decnet/netfilter/Kconfig" 204source "net/bridge/netfilter/Kconfig" 205 206endif 207 208source "net/bpfilter/Kconfig" 209 210source "net/dccp/Kconfig" 211source "net/sctp/Kconfig" 212source "net/rds/Kconfig" 213source "net/tipc/Kconfig" 214source "net/atm/Kconfig" 215source "net/l2tp/Kconfig" 216source "net/802/Kconfig" 217source "net/bridge/Kconfig" 218source "net/dsa/Kconfig" 219source "net/8021q/Kconfig" 220source "net/decnet/Kconfig" 221source "net/llc/Kconfig" 222source "drivers/net/appletalk/Kconfig" 223source "net/x25/Kconfig" 224source "net/lapb/Kconfig" 225source "net/phonet/Kconfig" 226source "net/6lowpan/Kconfig" 227source "net/ieee802154/Kconfig" 228source "net/mac802154/Kconfig" 229source "net/sched/Kconfig" 230source "net/dcb/Kconfig" 231source "net/dns_resolver/Kconfig" 232source "net/batman-adv/Kconfig" 233source "net/openvswitch/Kconfig" 234source "net/vmw_vsock/Kconfig" 235source "net/netlink/Kconfig" 236source "net/mpls/Kconfig" 237source "net/nsh/Kconfig" 238source "net/hsr/Kconfig" 239source "net/switchdev/Kconfig" 240source "net/l3mdev/Kconfig" 241source "net/qrtr/Kconfig" 242source "net/ncsi/Kconfig" 243 244config RPS 245 bool 246 depends on SMP && SYSFS 247 default y 248 249config RFS_ACCEL 250 bool 251 depends on RPS 252 select CPU_RMAP 253 default y 254 255config XPS 256 bool 257 depends on SMP 258 default y 259 260config HWBM 261 bool 262 263config 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 271config 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 279config NET_RX_BUSY_POLL 280 bool 281 default y 282 283config BQL 284 bool 285 depends on SYSFS 286 select DQL 287 default y 288 289config 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 304config 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 319config 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 331menu "Network testing" 332 333config 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 348config 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 359endmenu 360 361endmenu 362 363source "net/ax25/Kconfig" 364source "net/can/Kconfig" 365source "net/bluetooth/Kconfig" 366source "net/rxrpc/Kconfig" 367source "net/kcm/Kconfig" 368source "net/strparser/Kconfig" 369 370config FIB_RULES 371 bool 372 373menuconfig WIRELESS 374 bool "Wireless" 375 depends on !S390 376 default y 377 378if WIRELESS 379 380source "net/wireless/Kconfig" 381source "net/mac80211/Kconfig" 382 383endif # WIRELESS 384 385source "net/wimax/Kconfig" 386 387source "net/rfkill/Kconfig" 388source "net/9p/Kconfig" 389source "net/caif/Kconfig" 390source "net/ceph/Kconfig" 391source "net/nfc/Kconfig" 392source "net/psample/Kconfig" 393source "net/ife/Kconfig" 394 395config 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 403config 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 411config DST_CACHE 412 bool 413 default n 414 415config GRO_CELLS 416 bool 417 default n 418 419config SOCK_VALIDATE_XMIT 420 bool 421 422config 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 430config NET_DEVLINK 431 bool 432 default n 433 imply NET_DROP_MONITOR 434 435config PAGE_POOL 436 bool 437 438config FAILOVER 439 tristate "Generic failover module" 440 help 441 The failover module provides a generic interface for paravirtual 442 drivers to register a netdev and a set of ops with a failover 443 instance. The ops are used as event handlers that get called to 444 handle netdev register/unregister/link change/name change events 445 on slave pci ethernet devices with the same mac address as the 446 failover netdev. This enables paravirtual drivers to use a 447 VF as an accelerated low latency datapath. It also allows live 448 migration of VMs with direct attached VFs by failing over to the 449 paravirtual datapath when the VF is unplugged. 450 451endif # if NET 452 453# Used by archs to tell that they support BPF JIT compiler plus which flavour. 454# Only one of the two can be selected for a specific arch since eBPF JIT supersedes 455# the cBPF JIT. 456 457# Classic BPF JIT (cBPF) 458config HAVE_CBPF_JIT 459 bool 460 461# Extended BPF JIT (eBPF) 462config HAVE_EBPF_JIT 463 bool 464