1# 2# Network configuration 3# 4 5menu "Networking" 6 7config NET 8 bool "Networking support" 9 ---help--- 10 Unless you really know what you are doing, you should say Y here. 11 The reason is that some programs need kernel networking support even 12 when running on a stand-alone machine that isn't connected to any 13 other computer. 14 15 If you are upgrading from an older kernel, you 16 should consider updating your networking tools too because changes 17 in the kernel and the tools often go hand in hand. The tools are 18 contained in the package net-tools, the location and version number 19 of which are given in <file:Documentation/Changes>. 20 21 For a general introduction to Linux networking, it is highly 22 recommended to read the NET-HOWTO, available from 23 <http://www.tldp.org/docs.html#howto>. 24 25# Make sure that all config symbols are dependent on NET 26if NET 27 28menu "Networking options" 29 30config NETDEBUG 31 bool "Network packet debugging" 32 help 33 You can say Y here if you want to get additional messages useful in 34 debugging bad packets, but can overwhelm logs under denial of service 35 attacks. 36 37source "net/packet/Kconfig" 38source "net/unix/Kconfig" 39source "net/xfrm/Kconfig" 40 41config INET 42 bool "TCP/IP networking" 43 ---help--- 44 These are the protocols used on the Internet and on most local 45 Ethernets. It is highly recommended to say Y here (this will enlarge 46 your kernel by about 144 KB), since some programs (e.g. the X window 47 system) use TCP/IP even if your machine is not connected to any 48 other computer. You will get the so-called loopback device which 49 allows you to ping yourself (great fun, that!). 50 51 For an excellent introduction to Linux networking, please read the 52 Linux Networking HOWTO, available from 53 <http://www.tldp.org/docs.html#howto>. 54 55 If you say Y here and also to "/proc file system support" and 56 "Sysctl support" below, you can change various aspects of the 57 behavior of the TCP/IP code by writing to the (virtual) files in 58 /proc/sys/net/ipv4/*; the options are explained in the file 59 <file:Documentation/networking/ip-sysctl.txt>. 60 61 Short answer: say Y. 62 63if INET 64source "net/ipv4/Kconfig" 65source "net/ipv6/Kconfig" 66source "net/netlabel/Kconfig" 67 68endif # if INET 69 70config NETWORK_SECMARK 71 bool "Security Marking" 72 help 73 This enables security marking of network packets, similar 74 to nfmark, but designated for security purposes. 75 If you are unsure how to answer this question, answer N. 76 77menuconfig NETFILTER 78 bool "Network packet filtering framework (Netfilter)" 79 ---help--- 80 Netfilter is a framework for filtering and mangling network packets 81 that pass through your Linux box. 82 83 The most common use of packet filtering is to run your Linux box as 84 a firewall protecting a local network from the Internet. The type of 85 firewall provided by this kernel support is called a "packet 86 filter", which means that it can reject individual network packets 87 based on type, source, destination etc. The other kind of firewall, 88 a "proxy-based" one, is more secure but more intrusive and more 89 bothersome to set up; it inspects the network traffic much more 90 closely, modifies it and has knowledge about the higher level 91 protocols, which a packet filter lacks. Moreover, proxy-based 92 firewalls often require changes to the programs running on the local 93 clients. Proxy-based firewalls don't need support by the kernel, but 94 they are often combined with a packet filter, which only works if 95 you say Y here. 96 97 You should also say Y here if you intend to use your Linux box as 98 the gateway to the Internet for a local network of machines without 99 globally valid IP addresses. This is called "masquerading": if one 100 of the computers on your local network wants to send something to 101 the outside, your box can "masquerade" as that computer, i.e. it 102 forwards the traffic to the intended outside destination, but 103 modifies the packets to make it look like they came from the 104 firewall box itself. It works both ways: if the outside host 105 replies, the Linux box will silently forward the traffic to the 106 correct local computer. This way, the computers on your local net 107 are completely invisible to the outside world, even though they can 108 reach the outside and can receive replies. It is even possible to 109 run globally visible servers from within a masqueraded local network 110 using a mechanism called portforwarding. Masquerading is also often 111 called NAT (Network Address Translation). 112 113 Another use of Netfilter is in transparent proxying: if a machine on 114 the local network tries to connect to an outside host, your Linux 115 box can transparently forward the traffic to a local server, 116 typically a caching proxy server. 117 118 Yet another use of Netfilter is building a bridging firewall. Using 119 a bridge with Network packet filtering enabled makes iptables "see" 120 the bridged traffic. For filtering on the lower network and Ethernet 121 protocols over the bridge, use ebtables (under bridge netfilter 122 configuration). 123 124 Various modules exist for netfilter which replace the previous 125 masquerading (ipmasqadm), packet filtering (ipchains), transparent 126 proxying, and portforwarding mechanisms. Please see 127 <file:Documentation/Changes> under "iptables" for the location of 128 these packages. 129 130 Make sure to say N to "Fast switching" below if you intend to say Y 131 here, as Fast switching currently bypasses netfilter. 132 133 Chances are that you should say Y here if you compile a kernel which 134 will run as a router and N for regular hosts. If unsure, say N. 135 136if NETFILTER 137 138config NETFILTER_DEBUG 139 bool "Network packet filtering debugging" 140 depends on NETFILTER 141 help 142 You can say Y here if you want to get additional messages useful in 143 debugging the netfilter code. 144 145config BRIDGE_NETFILTER 146 bool "Bridged IP/ARP packets filtering" 147 depends on BRIDGE && NETFILTER && INET 148 default y 149 ---help--- 150 Enabling this option will let arptables resp. iptables see bridged 151 ARP resp. IP traffic. If you want a bridging firewall, you probably 152 want this option enabled. 153 Enabling or disabling this option doesn't enable or disable 154 ebtables. 155 156 If unsure, say N. 157 158source "net/netfilter/Kconfig" 159source "net/ipv4/netfilter/Kconfig" 160source "net/ipv6/netfilter/Kconfig" 161source "net/decnet/netfilter/Kconfig" 162source "net/bridge/netfilter/Kconfig" 163 164endif 165 166source "net/dccp/Kconfig" 167source "net/sctp/Kconfig" 168source "net/tipc/Kconfig" 169source "net/atm/Kconfig" 170source "net/bridge/Kconfig" 171source "net/8021q/Kconfig" 172source "net/decnet/Kconfig" 173source "net/llc/Kconfig" 174source "net/ipx/Kconfig" 175source "drivers/net/appletalk/Kconfig" 176source "net/x25/Kconfig" 177source "net/lapb/Kconfig" 178source "net/econet/Kconfig" 179source "net/wanrouter/Kconfig" 180source "net/sched/Kconfig" 181 182menu "Network testing" 183 184config NET_PKTGEN 185 tristate "Packet Generator (USE WITH CAUTION)" 186 depends on PROC_FS 187 ---help--- 188 This module will inject preconfigured packets, at a configurable 189 rate, out of a given interface. It is used for network interface 190 stress testing and performance analysis. If you don't understand 191 what was just said, you don't need it: say N. 192 193 Documentation on how to use the packet generator can be found 194 at <file:Documentation/networking/pktgen.txt>. 195 196 To compile this code as a module, choose M here: the 197 module will be called pktgen. 198 199config NET_TCPPROBE 200 tristate "TCP connection probing" 201 depends on INET && EXPERIMENTAL && PROC_FS && KPROBES 202 ---help--- 203 This module allows for capturing the changes to TCP connection 204 state in response to incoming packets. It is used for debugging 205 TCP congestion avoidance modules. If you don't understand 206 what was just said, you don't need it: say N. 207 208 Documentation on how to use TCP connection probing can be found 209 at http://linux-net.osdl.org/index.php/TcpProbe 210 211 To compile this code as a module, choose M here: the 212 module will be called tcp_probe. 213 214endmenu 215 216endmenu 217 218source "net/ax25/Kconfig" 219source "net/irda/Kconfig" 220source "net/bluetooth/Kconfig" 221source "net/ieee80211/Kconfig" 222 223config WIRELESS_EXT 224 bool 225 226config FIB_RULES 227 bool 228 229endif # if NET 230endmenu # Networking 231 232