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 MAX_SKB_FRAGS 255 int "Maximum number of fragments per skb_shared_info" 256 range 17 45 257 default 17 258 help 259 Having more fragments per skb_shared_info can help GRO efficiency. 260 This helps BIG TCP workloads, but might expose bugs in some 261 legacy drivers. 262 This also increases memory overhead of small packets, 263 and in drivers using build_skb(). 264 If unsure, say 17. 265 266config RPS 267 bool 268 depends on SMP && SYSFS 269 default y 270 271config RFS_ACCEL 272 bool 273 depends on RPS 274 select CPU_RMAP 275 default y 276 277config SOCK_RX_QUEUE_MAPPING 278 bool 279 280config XPS 281 bool 282 depends on SMP 283 select SOCK_RX_QUEUE_MAPPING 284 default y 285 286config HWBM 287 bool 288 289config CGROUP_NET_PRIO 290 bool "Network priority cgroup" 291 depends on CGROUPS 292 select SOCK_CGROUP_DATA 293 help 294 Cgroup subsystem for use in assigning processes to network priorities on 295 a per-interface basis. 296 297config CGROUP_NET_CLASSID 298 bool "Network classid cgroup" 299 depends on CGROUPS 300 select SOCK_CGROUP_DATA 301 help 302 Cgroup subsystem for use as general purpose socket classid marker that is 303 being used in cls_cgroup and for netfilter matching. 304 305config NET_RX_BUSY_POLL 306 bool 307 default y if !PREEMPT_RT 308 309config BQL 310 bool 311 depends on SYSFS 312 select DQL 313 default y 314 315config BPF_STREAM_PARSER 316 bool "enable BPF STREAM_PARSER" 317 depends on INET 318 depends on BPF_SYSCALL 319 depends on CGROUP_BPF 320 select STREAM_PARSER 321 select NET_SOCK_MSG 322 help 323 Enabling this allows a TCP stream parser to be used with 324 BPF_MAP_TYPE_SOCKMAP. 325 326config NET_FLOW_LIMIT 327 bool 328 depends on RPS 329 default y 330 help 331 The network stack has to drop packets when a receive processing CPU's 332 backlog reaches netdev_max_backlog. If a few out of many active flows 333 generate the vast majority of load, drop their traffic earlier to 334 maintain capacity for the other flows. This feature provides servers 335 with many clients some protection against DoS by a single (spoofed) 336 flow that greatly exceeds average workload. 337 338menu "Network testing" 339 340config NET_PKTGEN 341 tristate "Packet Generator (USE WITH CAUTION)" 342 depends on INET && PROC_FS 343 help 344 This module will inject preconfigured packets, at a configurable 345 rate, out of a given interface. It is used for network interface 346 stress testing and performance analysis. If you don't understand 347 what was just said, you don't need it: say N. 348 349 Documentation on how to use the packet generator can be found 350 at <file:Documentation/networking/pktgen.rst>. 351 352 To compile this code as a module, choose M here: the 353 module will be called pktgen. 354 355config NET_DROP_MONITOR 356 tristate "Network packet drop alerting service" 357 depends on INET && TRACEPOINTS 358 help 359 This feature provides an alerting service to userspace in the 360 event that packets are discarded in the network stack. Alerts 361 are broadcast via netlink socket to any listening user space 362 process. If you don't need network drop alerts, or if you are ok 363 just checking the various proc files and other utilities for 364 drop statistics, say N here. 365 366endmenu 367 368endmenu 369 370source "net/ax25/Kconfig" 371source "net/can/Kconfig" 372source "net/bluetooth/Kconfig" 373source "net/rxrpc/Kconfig" 374source "net/kcm/Kconfig" 375source "net/strparser/Kconfig" 376source "net/mctp/Kconfig" 377 378config FIB_RULES 379 bool 380 381menuconfig WIRELESS 382 bool "Wireless" 383 depends on !S390 384 default y 385 386if WIRELESS 387 388source "net/wireless/Kconfig" 389source "net/mac80211/Kconfig" 390 391endif # WIRELESS 392 393source "net/rfkill/Kconfig" 394source "net/9p/Kconfig" 395source "net/caif/Kconfig" 396source "net/ceph/Kconfig" 397source "net/nfc/Kconfig" 398source "net/psample/Kconfig" 399source "net/ife/Kconfig" 400 401config LWTUNNEL 402 bool "Network light weight tunnels" 403 help 404 This feature provides an infrastructure to support light weight 405 tunnels like mpls. There is no netdevice associated with a light 406 weight tunnel endpoint. Tunnel encapsulation parameters are stored 407 with light weight tunnel state associated with fib routes. 408 409config LWTUNNEL_BPF 410 bool "Execute BPF program as route nexthop action" 411 depends on LWTUNNEL && INET 412 default y if LWTUNNEL=y 413 help 414 Allows to run BPF programs as a nexthop action following a route 415 lookup for incoming and outgoing packets. 416 417config DST_CACHE 418 bool 419 default n 420 421config GRO_CELLS 422 bool 423 default n 424 425config SOCK_VALIDATE_XMIT 426 bool 427 428config NET_SELFTESTS 429 def_tristate PHYLIB 430 depends on PHYLIB && INET 431 432config NET_SOCK_MSG 433 bool 434 default n 435 help 436 The NET_SOCK_MSG provides a framework for plain sockets (e.g. TCP) or 437 ULPs (upper layer modules, e.g. TLS) to process L7 application data 438 with the help of BPF programs. 439 440config NET_DEVLINK 441 bool 442 default n 443 444config PAGE_POOL 445 bool 446 447config PAGE_POOL_STATS 448 default n 449 bool "Page pool stats" 450 depends on PAGE_POOL 451 help 452 Enable page pool statistics to track page allocation and recycling 453 in page pools. This option incurs additional CPU cost in allocation 454 and recycle paths and additional memory cost to store the statistics. 455 These statistics are only available if this option is enabled and if 456 the driver using the page pool supports exporting this data. 457 458 If unsure, say N. 459 460config FAILOVER 461 tristate "Generic failover module" 462 help 463 The failover module provides a generic interface for paravirtual 464 drivers to register a netdev and a set of ops with a failover 465 instance. The ops are used as event handlers that get called to 466 handle netdev register/unregister/link change/name change events 467 on slave pci ethernet devices with the same mac address as the 468 failover netdev. This enables paravirtual drivers to use a 469 VF as an accelerated low latency datapath. It also allows live 470 migration of VMs with direct attached VFs by failing over to the 471 paravirtual datapath when the VF is unplugged. 472 473config ETHTOOL_NETLINK 474 bool "Netlink interface for ethtool" 475 default y 476 help 477 An alternative userspace interface for ethtool based on generic 478 netlink. It provides better extensibility and some new features, 479 e.g. notification messages. 480 481config NETDEV_ADDR_LIST_TEST 482 tristate "Unit tests for device address list" 483 default KUNIT_ALL_TESTS 484 depends on KUNIT 485 486endif # if NET 487