kernel-ark/net/ipv4
Thomas Graf d0daebc3d6 ipv4: Add interface option to enable routing of 127.0.0.0/8
Routing of 127/8 is tradtionally forbidden, we consider
packets from that address block martian when routing and do
not process corresponding ARP requests.

This is a sane default but renders a huge address space
practically unuseable.

The RFC states that no address within the 127/8 block should
ever appear on any network anywhere but it does not forbid
the use of such addresses outside of the loopback device in
particular. For example to address a pool of virtual guests
behind a load balancer.

This patch adds a new interface option 'route_localnet'
enabling routing of the 127/8 address block and processing
of ARP requests on a specific interface.

Note that for the feature to work, the default local route
covering 127/8 dev lo needs to be removed.

Example:
  $ sysctl -w net.ipv4.conf.eth0.route_localnet=1
  $ ip route del 127.0.0.0/8 dev lo table local
  $ ip addr add 127.1.0.1/16 dev eth0
  $ ip route flush cache

V2: Fix invalid check to auto flush cache (thanks davem)

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-12 15:25:46 -07:00
..
netfilter Merge branch 'master' of git://1984.lsi.us.es/net-next 2012-06-11 12:56:14 -07:00
af_inet.c net: Remove casts to same type 2012-06-04 11:45:11 -04:00
ah4.c net: ipv4 and ipv6: Convert printk(KERN_DEBUG to pr_debug 2012-05-16 01:01:03 -04:00
arp.c ipv4: Add interface option to enable routing of 127.0.0.0/8 2012-06-12 15:25:46 -07:00
cipso_ipv4.c ipv4: Convert call_rcu() to kfree_rcu(), drop opt_kfree_rcu() 2012-02-21 09:03:31 -08:00
datagram.c
devinet.c ipv4: Add interface option to enable routing of 127.0.0.0/8 2012-06-12 15:25:46 -07:00
esp4.c xfrm: take net hdr len into account for esp payload size calculation 2012-05-27 01:08:29 -04:00
fib_frontend.c net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
fib_lookup.h
fib_rules.c ipv4: Stop using NLA_PUT*(). 2012-04-02 04:33:43 -04:00
fib_semantics.c ipv4: fix the rcu race between free_fib_info and ip_route_output_slow 2012-05-24 00:28:21 -04:00
fib_trie.c inet: Add inetpeer tree roots to the FIB tables. 2012-06-11 02:09:16 -07:00
gre.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
icmp.c ipv4: Kill ip_rt_frag_needed(). 2012-06-11 02:08:59 -07:00
igmp.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
inet_connection_sock.c tcp: do not create inetpeer on SYNACK message 2012-06-01 14:22:11 -04:00
inet_diag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-07 23:35:40 -04:00
inet_fragment.c inetpeer: add parameter net for inet_getpeer_v4,v6 2012-06-08 14:27:23 -07:00
inet_hashtables.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
inet_lro.c net: add skb frag size accessors 2011-10-19 03:10:46 -04:00
inet_timewait_sock.c net: ipv4 and ipv6: Convert printk(KERN_DEBUG to pr_debug 2012-05-16 01:01:03 -04:00
inetpeer.c inet: Add family scope inetpeer flushes. 2012-06-11 02:09:10 -07:00
ip_forward.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
ip_fragment.c inet: Pass inetpeer root into inet_getpeer*() interfaces. 2012-06-09 19:12:36 -07:00
ip_gre.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
ip_input.c net: Convert net_ratelimit uses to net_<level>_ratelimited 2012-05-15 13:45:03 -04:00
ip_options.c net: Convert net_ratelimit uses to net_<level>_ratelimited 2012-05-15 13:45:03 -04:00
ip_output.c net: use consume_skb() in place of kfree_skb() 2012-06-04 11:27:40 -04:00
ip_sockglue.c net: IP_MULTICAST_IF setsockopt now recognizes struct mreq 2012-05-07 23:03:22 -04:00
ipcomp.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
ipconfig.c net/ipv4/ipconfig: neaten __setup placement 2012-05-20 04:06:16 -04:00
ipip.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
ipmr.c net: Convert net_ratelimit uses to net_<level>_ratelimited 2012-05-15 13:45:03 -04:00
Kconfig net: delete all instances of special processing for token ring 2012-05-15 20:14:35 -04:00
Makefile tcp memory pressure controls 2011-12-12 19:04:10 -05:00
netfilter.c net: Delete all remaining instances of ctl_path 2012-04-20 21:22:30 -04:00
ping.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2012-05-23 17:42:39 -07:00
proc.c tcp: reduce out_of_order memory use 2012-03-19 16:53:08 -04:00
protocol.c
raw.c ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
route.c ipv4: Add interface option to enable routing of 127.0.0.0/8 2012-06-12 15:25:46 -07:00
syncookies.c tcp: fix syncookie regression 2012-03-11 15:52:12 -07:00
sysctl_net_ipv4.c tcp: early retransmit 2012-05-02 20:56:10 -04:00
tcp_bic.c tcp: fix undo after RTO for BIC 2012-01-20 14:17:26 -05:00
tcp_cong.c tcp: bool conversions 2012-05-17 14:59:59 -04:00
tcp_cubic.c tcp: fix undo after RTO for CUBIC 2012-01-20 14:17:26 -05:00
tcp_diag.c inet_diag: Rename inet_diag_req into inet_diag_req_v2 2012-01-11 12:56:06 -08:00
tcp_highspeed.c
tcp_htcp.c
tcp_hybla.c tcp: bool conversions 2012-05-17 14:59:59 -04:00
tcp_illinois.c
tcp_input.c tcp: take care of overlaps in tcp_try_coalesce() 2012-05-24 00:28:21 -04:00
tcp_ipv4.c [PATCH] tcp: Cache inetpeer in timewait socket, and only when necessary. 2012-06-09 14:56:12 -07:00
tcp_lp.c
tcp_memcontrol.c memcg: decrement static keys at real destroy time 2012-05-29 16:22:28 -07:00
tcp_minisocks.c [PATCH] tcp: Cache inetpeer in timewait socket, and only when necessary. 2012-06-09 14:56:12 -07:00
tcp_output.c tcp: tcp_make_synack() consumes dst parameter 2012-06-04 11:27:39 -04:00
tcp_probe.c net: cleanup unsigned to unsigned int 2012-04-15 12:44:40 -04:00
tcp_scalable.c
tcp_timer.c tcp: early retransmit: delayed fast retransmit 2012-05-02 20:56:10 -04:00
tcp_vegas.c
tcp_vegas.h
tcp_veno.c
tcp_westwood.c
tcp_yeah.c
tcp.c mm: add a low limit to alloc_large_system_hash 2012-05-24 00:28:21 -04:00
tunnel4.c net: Convert printks to pr_<level> 2012-03-11 23:42:51 -07:00
udp_diag.c udp_diag: implement idiag_get_info for udp/udplite to get queue information 2012-04-25 20:43:01 -04:00
udp_impl.h ipv4: fix checkpatch errors 2012-04-15 12:37:19 -04:00
udp.c mm: add a low limit to alloc_large_system_hash 2012-05-24 00:28:21 -04:00
udplite.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00
xfrm4_input.c
xfrm4_mode_beet.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm4_mode_transport.c
xfrm4_mode_tunnel.c ipsec: be careful of non existing mac headers 2012-02-23 16:50:45 -05:00
xfrm4_output.c
xfrm4_policy.c inet: Hide route peer accesses behind helpers. 2012-06-11 02:08:47 -07:00
xfrm4_state.c net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules 2011-10-31 19:30:30 -04:00
xfrm4_tunnel.c net: ipv4: Standardize prefixes for message logging 2012-03-12 17:05:21 -07:00