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 NET_REDIRECT 56 bool 57 58 config SKB_EXTENSIONS 59 bool 60 61 menu "Networking options" 62 63 source "net/packet/Kconfig" 64 source "net/unix/Kconfig" 65 source "net/tls/Kconfig" 66 source "net/xfrm/Kconfig" 67 source "net/iucv/Kconfig" 68 source "net/smc/Kconfig" 69 source "net/xdp/Kconfig" 70 71 config 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 93 if INET 94 source "net/ipv4/Kconfig" 95 source "net/ipv6/Kconfig" 96 source "net/netlabel/Kconfig" 97 source "net/mptcp/Kconfig" 98 99 endif # if INET 100 101 config 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. 107 108 config NET_PTP_CLASSIFY 109 def_bool n 110 111 config 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. 121 122 menuconfig 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. 174 175 if NETFILTER 176 177 config 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. 187 188 config 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. 203 204 source "net/netfilter/Kconfig" 205 source "net/ipv4/netfilter/Kconfig" 206 source "net/ipv6/netfilter/Kconfig" 207 source "net/decnet/netfilter/Kconfig" 208 source "net/bridge/netfilter/Kconfig" 209 210 endif 211 212 source "net/bpfilter/Kconfig" 213 214 source "net/dccp/Kconfig" 215 source "net/sctp/Kconfig" 216 source "net/rds/Kconfig" 217 source "net/tipc/Kconfig" 218 source "net/atm/Kconfig" 219 source "net/l2tp/Kconfig" 220 source "net/802/Kconfig" 221 source "net/bridge/Kconfig" 222 source "net/dsa/Kconfig" 223 source "net/8021q/Kconfig" 224 source "net/decnet/Kconfig" 225 source "net/llc/Kconfig" 226 source "drivers/net/appletalk/Kconfig" 227 source "net/x25/Kconfig" 228 source "net/lapb/Kconfig" 229 source "net/phonet/Kconfig" 230 source "net/6lowpan/Kconfig" 231 source "net/ieee802154/Kconfig" 232 source "net/mac802154/Kconfig" 233 source "net/sched/Kconfig" 234 source "net/dcb/Kconfig" 235 source "net/dns_resolver/Kconfig" 236 source "net/batman-adv/Kconfig" 237 source "net/openvswitch/Kconfig" 238 source "net/vmw_vsock/Kconfig" 239 source "net/netlink/Kconfig" 240 source "net/mpls/Kconfig" 241 source "net/nsh/Kconfig" 242 source "net/hsr/Kconfig" 243 source "net/switchdev/Kconfig" 244 source "net/l3mdev/Kconfig" 245 source "net/qrtr/Kconfig" 246 source "net/ncsi/Kconfig" 247 248 config RPS 249 bool 250 depends on SMP && SYSFS 251 default y 252 253 config RFS_ACCEL 254 bool 255 depends on RPS 256 select CPU_RMAP 257 default y 258 259 config XPS 260 bool 261 depends on SMP 262 default y 263 264 config HWBM 265 bool 266 267 config 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. 274 275 config 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. 282 283 config NET_RX_BUSY_POLL 284 bool 285 default y 286 287 config BQL 288 bool 289 depends on SYSFS 290 select DQL 291 default y 292 293 config 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) 307 308 config 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. 322 323 config 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. 334 335 menu "Network testing" 336 337 config 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. 351 352 config 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. 362 363 endmenu 364 365 endmenu 366 367 source "net/ax25/Kconfig" 368 source "net/can/Kconfig" 369 source "net/bluetooth/Kconfig" 370 source "net/rxrpc/Kconfig" 371 source "net/kcm/Kconfig" 372 source "net/strparser/Kconfig" 373 374 config FIB_RULES 375 bool 376 377 menuconfig WIRELESS 378 bool "Wireless" 379 depends on !S390 380 default y 381 382 if WIRELESS 383 384 source "net/wireless/Kconfig" 385 source "net/mac80211/Kconfig" 386 387 endif # WIRELESS 388 389 source "net/rfkill/Kconfig" 390 source "net/9p/Kconfig" 391 source "net/caif/Kconfig" 392 source "net/ceph/Kconfig" 393 source "net/nfc/Kconfig" 394 source "net/psample/Kconfig" 395 source "net/ife/Kconfig" 396 397 config LWTUNNEL 398 bool "Network light weight tunnels" 399 help 400 This feature provides an infrastructure to support light weight 401 tunnels like mpls. There is no netdevice associated with a light 402 weight tunnel endpoint. Tunnel encapsulation parameters are stored 403 with light weight tunnel state associated with fib routes. 404 405 config LWTUNNEL_BPF 406 bool "Execute BPF program as route nexthop action" 407 depends on LWTUNNEL && INET 408 default y if LWTUNNEL=y 409 help 410 Allows to run BPF programs as a nexthop action following a route 411 lookup for incoming and outgoing packets. 412 413 config DST_CACHE 414 bool 415 default n 416 417 config GRO_CELLS 418 bool 419 default n 420 421 config SOCK_VALIDATE_XMIT 422 bool 423 424 config NET_SOCK_MSG 425 bool 426 default n 427 help 428 The NET_SOCK_MSG provides a framework for plain sockets (e.g. TCP) or 429 ULPs (upper layer modules, e.g. TLS) to process L7 application data 430 with the help of BPF programs. 431 432 config NET_DEVLINK 433 bool 434 default n 435 436 config PAGE_POOL 437 bool 438 439 config FAILOVER 440 tristate "Generic failover module" 441 help 442 The failover module provides a generic interface for paravirtual 443 drivers to register a netdev and a set of ops with a failover 444 instance. The ops are used as event handlers that get called to 445 handle netdev register/unregister/link change/name change events 446 on slave pci ethernet devices with the same mac address as the 447 failover netdev. This enables paravirtual drivers to use a 448 VF as an accelerated low latency datapath. It also allows live 449 migration of VMs with direct attached VFs by failing over to the 450 paravirtual datapath when the VF is unplugged. 451 452 config ETHTOOL_NETLINK 453 bool "Netlink interface for ethtool" 454 default y 455 help 456 An alternative userspace interface for ethtool based on generic 457 netlink. It provides better extensibility and some new features, 458 e.g. notification messages. 459 460 endif # if NET 461 462 # Used by archs to tell that they support BPF JIT compiler plus which flavour. 463 # Only one of the two can be selected for a specific arch since eBPF JIT supersedes 464 # the cBPF JIT. 465 466 # Classic BPF JIT (cBPF) 467 config HAVE_CBPF_JIT 468 bool 469 470 # Extended BPF JIT (eBPF) 471 config HAVE_EBPF_JIT 472 bool 473