xref: /openbmc/linux/net/Kconfig (revision 2612e3bbc0386368a850140a6c9b990cd496a5ec)
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 NET_HANDSHAKE
72 	bool
73 	depends on SUNRPC || NVME_TARGET_TCP || NVME_TCP
74 	default y
75 
76 config NET_HANDSHAKE_KUNIT_TEST
77 	tristate "KUnit tests for the handshake upcall mechanism" if !KUNIT_ALL_TESTS
78 	default KUNIT_ALL_TESTS
79 	depends on KUNIT
80 	help
81 	  This builds the KUnit tests for the handshake upcall mechanism.
82 
83 	  KUnit tests run during boot and output the results to the debug
84 	  log in TAP format (https://testanything.org/). Only useful for
85 	  kernel devs running KUnit test harness and are not for inclusion
86 	  into a production build.
87 
88 	  For more information on KUnit and unit tests in general, refer
89 	  to the KUnit documentation in Documentation/dev-tools/kunit/.
90 
91 config INET
92 	bool "TCP/IP networking"
93 	help
94 	  These are the protocols used on the Internet and on most local
95 	  Ethernets. It is highly recommended to say Y here (this will enlarge
96 	  your kernel by about 400 KB), since some programs (e.g. the X window
97 	  system) use TCP/IP even if your machine is not connected to any
98 	  other computer. You will get the so-called loopback device which
99 	  allows you to ping yourself (great fun, that!).
100 
101 	  For an excellent introduction to Linux networking, please read the
102 	  Linux Networking HOWTO, available from
103 	  <http://www.tldp.org/docs.html#howto>.
104 
105 	  If you say Y here and also to "/proc file system support" and
106 	  "Sysctl support" below, you can change various aspects of the
107 	  behavior of the TCP/IP code by writing to the (virtual) files in
108 	  /proc/sys/net/ipv4/*; the options are explained in the file
109 	  <file:Documentation/networking/ip-sysctl.rst>.
110 
111 	  Short answer: say Y.
112 
113 if INET
114 source "net/ipv4/Kconfig"
115 source "net/ipv6/Kconfig"
116 source "net/netlabel/Kconfig"
117 source "net/mptcp/Kconfig"
118 
119 endif # if INET
120 
121 config NETWORK_SECMARK
122 	bool "Security Marking"
123 	help
124 	  This enables security marking of network packets, similar
125 	  to nfmark, but designated for security purposes.
126 	  If you are unsure how to answer this question, answer N.
127 
128 config NET_PTP_CLASSIFY
129 	def_bool n
130 
131 config NETWORK_PHY_TIMESTAMPING
132 	bool "Timestamping in PHY devices"
133 	select NET_PTP_CLASSIFY
134 	help
135 	  This allows timestamping of network packets by PHYs (or
136 	  other MII bus snooping devices) with hardware timestamping
137 	  capabilities. This option adds some overhead in the transmit
138 	  and receive paths.
139 
140 	  If you are unsure how to answer this question, answer N.
141 
142 menuconfig NETFILTER
143 	bool "Network packet filtering framework (Netfilter)"
144 	help
145 	  Netfilter is a framework for filtering and mangling network packets
146 	  that pass through your Linux box.
147 
148 	  The most common use of packet filtering is to run your Linux box as
149 	  a firewall protecting a local network from the Internet. The type of
150 	  firewall provided by this kernel support is called a "packet
151 	  filter", which means that it can reject individual network packets
152 	  based on type, source, destination etc. The other kind of firewall,
153 	  a "proxy-based" one, is more secure but more intrusive and more
154 	  bothersome to set up; it inspects the network traffic much more
155 	  closely, modifies it and has knowledge about the higher level
156 	  protocols, which a packet filter lacks. Moreover, proxy-based
157 	  firewalls often require changes to the programs running on the local
158 	  clients. Proxy-based firewalls don't need support by the kernel, but
159 	  they are often combined with a packet filter, which only works if
160 	  you say Y here.
161 
162 	  You should also say Y here if you intend to use your Linux box as
163 	  the gateway to the Internet for a local network of machines without
164 	  globally valid IP addresses. This is called "masquerading": if one
165 	  of the computers on your local network wants to send something to
166 	  the outside, your box can "masquerade" as that computer, i.e. it
167 	  forwards the traffic to the intended outside destination, but
168 	  modifies the packets to make it look like they came from the
169 	  firewall box itself. It works both ways: if the outside host
170 	  replies, the Linux box will silently forward the traffic to the
171 	  correct local computer. This way, the computers on your local net
172 	  are completely invisible to the outside world, even though they can
173 	  reach the outside and can receive replies. It is even possible to
174 	  run globally visible servers from within a masqueraded local network
175 	  using a mechanism called portforwarding. Masquerading is also often
176 	  called NAT (Network Address Translation).
177 
178 	  Another use of Netfilter is in transparent proxying: if a machine on
179 	  the local network tries to connect to an outside host, your Linux
180 	  box can transparently forward the traffic to a local server,
181 	  typically a caching proxy server.
182 
183 	  Yet another use of Netfilter is building a bridging firewall. Using
184 	  a bridge with Network packet filtering enabled makes iptables "see"
185 	  the bridged traffic. For filtering on the lower network and Ethernet
186 	  protocols over the bridge, use ebtables (under bridge netfilter
187 	  configuration).
188 
189 	  Various modules exist for netfilter which replace the previous
190 	  masquerading (ipmasqadm), packet filtering (ipchains), transparent
191 	  proxying, and portforwarding mechanisms. Please see
192 	  <file:Documentation/Changes> under "iptables" for the location of
193 	  these packages.
194 
195 if NETFILTER
196 
197 config NETFILTER_ADVANCED
198 	bool "Advanced netfilter configuration"
199 	depends on NETFILTER
200 	default y
201 	help
202 	  If you say Y here you can select between all the netfilter modules.
203 	  If you say N the more unusual ones will not be shown and the
204 	  basic ones needed by most people will default to 'M'.
205 
206 	  If unsure, say Y.
207 
208 config BRIDGE_NETFILTER
209 	tristate "Bridged IP/ARP packets filtering"
210 	depends on BRIDGE
211 	depends on NETFILTER && INET
212 	depends on NETFILTER_ADVANCED
213 	select NETFILTER_FAMILY_BRIDGE
214 	select SKB_EXTENSIONS
215 	help
216 	  Enabling this option will let arptables resp. iptables see bridged
217 	  ARP resp. IP traffic. If you want a bridging firewall, you probably
218 	  want this option enabled.
219 	  Enabling or disabling this option doesn't enable or disable
220 	  ebtables.
221 
222 	  If unsure, say N.
223 
224 source "net/netfilter/Kconfig"
225 source "net/ipv4/netfilter/Kconfig"
226 source "net/ipv6/netfilter/Kconfig"
227 source "net/bridge/netfilter/Kconfig"
228 
229 endif
230 
231 source "net/bpfilter/Kconfig"
232 
233 source "net/dccp/Kconfig"
234 source "net/sctp/Kconfig"
235 source "net/rds/Kconfig"
236 source "net/tipc/Kconfig"
237 source "net/atm/Kconfig"
238 source "net/l2tp/Kconfig"
239 source "net/802/Kconfig"
240 source "net/bridge/Kconfig"
241 source "net/dsa/Kconfig"
242 source "net/8021q/Kconfig"
243 source "net/llc/Kconfig"
244 source "drivers/net/appletalk/Kconfig"
245 source "net/x25/Kconfig"
246 source "net/lapb/Kconfig"
247 source "net/phonet/Kconfig"
248 source "net/6lowpan/Kconfig"
249 source "net/ieee802154/Kconfig"
250 source "net/mac802154/Kconfig"
251 source "net/sched/Kconfig"
252 source "net/dcb/Kconfig"
253 source "net/dns_resolver/Kconfig"
254 source "net/batman-adv/Kconfig"
255 source "net/openvswitch/Kconfig"
256 source "net/vmw_vsock/Kconfig"
257 source "net/netlink/Kconfig"
258 source "net/mpls/Kconfig"
259 source "net/nsh/Kconfig"
260 source "net/hsr/Kconfig"
261 source "net/switchdev/Kconfig"
262 source "net/l3mdev/Kconfig"
263 source "net/qrtr/Kconfig"
264 source "net/ncsi/Kconfig"
265 
266 config PCPU_DEV_REFCNT
267 	bool "Use percpu variables to maintain network device refcount"
268 	depends on SMP
269 	default y
270 	help
271 	  network device refcount are using per cpu variables if this option is set.
272 	  This can be forced to N to detect underflows (with a performance drop).
273 
274 config MAX_SKB_FRAGS
275 	int "Maximum number of fragments per skb_shared_info"
276 	range 17 45
277 	default 17
278 	help
279 	  Having more fragments per skb_shared_info can help GRO efficiency.
280 	  This helps BIG TCP workloads, but might expose bugs in some
281 	  legacy drivers.
282 	  This also increases memory overhead of small packets,
283 	  and in drivers using build_skb().
284 	  If unsure, say 17.
285 
286 config RPS
287 	bool
288 	depends on SMP && SYSFS
289 	default y
290 
291 config RFS_ACCEL
292 	bool
293 	depends on RPS
294 	select CPU_RMAP
295 	default y
296 
297 config SOCK_RX_QUEUE_MAPPING
298 	bool
299 
300 config XPS
301 	bool
302 	depends on SMP
303 	select SOCK_RX_QUEUE_MAPPING
304 	default y
305 
306 config HWBM
307 	bool
308 
309 config CGROUP_NET_PRIO
310 	bool "Network priority cgroup"
311 	depends on CGROUPS
312 	select SOCK_CGROUP_DATA
313 	help
314 	  Cgroup subsystem for use in assigning processes to network priorities on
315 	  a per-interface basis.
316 
317 config CGROUP_NET_CLASSID
318 	bool "Network classid cgroup"
319 	depends on CGROUPS
320 	select SOCK_CGROUP_DATA
321 	help
322 	  Cgroup subsystem for use as general purpose socket classid marker that is
323 	  being used in cls_cgroup and for netfilter matching.
324 
325 config NET_RX_BUSY_POLL
326 	bool
327 	default y if !PREEMPT_RT || (PREEMPT_RT && !NETCONSOLE)
328 
329 config BQL
330 	bool
331 	depends on SYSFS
332 	select DQL
333 	default y
334 
335 config BPF_STREAM_PARSER
336 	bool "enable BPF STREAM_PARSER"
337 	depends on INET
338 	depends on BPF_SYSCALL
339 	depends on CGROUP_BPF
340 	select STREAM_PARSER
341 	select NET_SOCK_MSG
342 	help
343 	  Enabling this allows a TCP stream parser to be used with
344 	  BPF_MAP_TYPE_SOCKMAP.
345 
346 config NET_FLOW_LIMIT
347 	bool
348 	depends on RPS
349 	default y
350 	help
351 	  The network stack has to drop packets when a receive processing CPU's
352 	  backlog reaches netdev_max_backlog. If a few out of many active flows
353 	  generate the vast majority of load, drop their traffic earlier to
354 	  maintain capacity for the other flows. This feature provides servers
355 	  with many clients some protection against DoS by a single (spoofed)
356 	  flow that greatly exceeds average workload.
357 
358 menu "Network testing"
359 
360 config NET_PKTGEN
361 	tristate "Packet Generator (USE WITH CAUTION)"
362 	depends on INET && PROC_FS
363 	help
364 	  This module will inject preconfigured packets, at a configurable
365 	  rate, out of a given interface.  It is used for network interface
366 	  stress testing and performance analysis.  If you don't understand
367 	  what was just said, you don't need it: say N.
368 
369 	  Documentation on how to use the packet generator can be found
370 	  at <file:Documentation/networking/pktgen.rst>.
371 
372 	  To compile this code as a module, choose M here: the
373 	  module will be called pktgen.
374 
375 config NET_DROP_MONITOR
376 	tristate "Network packet drop alerting service"
377 	depends on INET && TRACEPOINTS
378 	help
379 	  This feature provides an alerting service to userspace in the
380 	  event that packets are discarded in the network stack.  Alerts
381 	  are broadcast via netlink socket to any listening user space
382 	  process.  If you don't need network drop alerts, or if you are ok
383 	  just checking the various proc files and other utilities for
384 	  drop statistics, say N here.
385 
386 endmenu
387 
388 endmenu
389 
390 source "net/ax25/Kconfig"
391 source "net/can/Kconfig"
392 source "net/bluetooth/Kconfig"
393 source "net/rxrpc/Kconfig"
394 source "net/kcm/Kconfig"
395 source "net/strparser/Kconfig"
396 source "net/mctp/Kconfig"
397 
398 config FIB_RULES
399 	bool
400 
401 menuconfig WIRELESS
402 	bool "Wireless"
403 	depends on !S390
404 	default y
405 
406 if WIRELESS
407 
408 source "net/wireless/Kconfig"
409 source "net/mac80211/Kconfig"
410 
411 endif # WIRELESS
412 
413 source "net/rfkill/Kconfig"
414 source "net/9p/Kconfig"
415 source "net/caif/Kconfig"
416 source "net/ceph/Kconfig"
417 source "net/nfc/Kconfig"
418 source "net/psample/Kconfig"
419 source "net/ife/Kconfig"
420 
421 config LWTUNNEL
422 	bool "Network light weight tunnels"
423 	help
424 	  This feature provides an infrastructure to support light weight
425 	  tunnels like mpls. There is no netdevice associated with a light
426 	  weight tunnel endpoint. Tunnel encapsulation parameters are stored
427 	  with light weight tunnel state associated with fib routes.
428 
429 config LWTUNNEL_BPF
430 	bool "Execute BPF program as route nexthop action"
431 	depends on LWTUNNEL && INET
432 	default y if LWTUNNEL=y
433 	help
434 	  Allows to run BPF programs as a nexthop action following a route
435 	  lookup for incoming and outgoing packets.
436 
437 config DST_CACHE
438 	bool
439 	default n
440 
441 config GRO_CELLS
442 	bool
443 	default n
444 
445 config SOCK_VALIDATE_XMIT
446 	bool
447 
448 config NET_SELFTESTS
449 	def_tristate PHYLIB
450 	depends on PHYLIB && INET
451 
452 config NET_SOCK_MSG
453 	bool
454 	default n
455 	help
456 	  The NET_SOCK_MSG provides a framework for plain sockets (e.g. TCP) or
457 	  ULPs (upper layer modules, e.g. TLS) to process L7 application data
458 	  with the help of BPF programs.
459 
460 config NET_DEVLINK
461 	bool
462 	default n
463 
464 config PAGE_POOL
465 	bool
466 
467 config PAGE_POOL_STATS
468 	default n
469 	bool "Page pool stats"
470 	depends on PAGE_POOL
471 	help
472 	  Enable page pool statistics to track page allocation and recycling
473 	  in page pools. This option incurs additional CPU cost in allocation
474 	  and recycle paths and additional memory cost to store the statistics.
475 	  These statistics are only available if this option is enabled and if
476 	  the driver using the page pool supports exporting this data.
477 
478 	  If unsure, say N.
479 
480 config FAILOVER
481 	tristate "Generic failover module"
482 	help
483 	  The failover module provides a generic interface for paravirtual
484 	  drivers to register a netdev and a set of ops with a failover
485 	  instance. The ops are used as event handlers that get called to
486 	  handle netdev register/unregister/link change/name change events
487 	  on slave pci ethernet devices with the same mac address as the
488 	  failover netdev. This enables paravirtual drivers to use a
489 	  VF as an accelerated low latency datapath. It also allows live
490 	  migration of VMs with direct attached VFs by failing over to the
491 	  paravirtual datapath when the VF is unplugged.
492 
493 config ETHTOOL_NETLINK
494 	bool "Netlink interface for ethtool"
495 	default y
496 	help
497 	  An alternative userspace interface for ethtool based on generic
498 	  netlink. It provides better extensibility and some new features,
499 	  e.g. notification messages.
500 
501 config NETDEV_ADDR_LIST_TEST
502 	tristate "Unit tests for device address list"
503 	default KUNIT_ALL_TESTS
504 	depends on KUNIT
505 
506 endif   # if NET
507