Commit 35a256fe authored by Tom Herbert's avatar Tom Herbert Committed by David S. Miller
Browse files

ipv6: Nonlocal bind 



Add support to allow non-local binds similar to how this was done for IPv4.
Non-local binds are very useful in emulating the Internet in a box, etc.

This add the ip_nonlocal_bind sysctl under ipv6.

Testing:

Set up nonlocal binding and receive routing on a host, e.g.:

ip -6 rule add from ::/0 iif eth0 lookup 200
ip -6 route add local 2001:0:0:1::/64 dev lo proto kernel scope host table 200
sysctl -w net.ipv6.ip_nonlocal_bind=1

Set up routing to 2001:0:0:1::/64 on peer to go to first host

ping6 -I 2001:0:0:1::1 peer-address -- to verify

Signed-off-by: default avatarTom Herbert <tom@herbertland.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5a10ecec

Documentation/networking/ip-sysctl.txt

+5 −0
Original line number Diff line number Diff line
@@ -1435,6 +1435,11 @@ mtu - INTEGER 
	Default Maximum Transfer Unit

	Default: 1280 (IPv6 required minimum)



ip_nonlocal_bind - BOOLEAN

	If set, allows processes to bind() to non-local IPv6 addresses,

	which can be quite useful - but may break some applications.

	Default: 0



router_probe_interval - INTEGER

	Minimum interval (in seconds) between Router Probing described

	in RFC4191.

include/net/netns/ipv6.h

+1 −0
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ struct netns_sysctl_ipv6 { 
	int auto_flowlabels;

	int icmpv6_time;

	int anycast_src_echo_reply;

	int ip_nonlocal_bind;

	int fwmark_reflect;

	int idgen_retries;

	int idgen_delay;

net/ipv4/ping.c

+2 −1
Original line number Diff line number Diff line
@@ -363,7 +363,8 @@ static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk, 
						    scoped);

		rcu_read_unlock();



		if (!(isk->freebind || isk->transparent || has_addr ||

		if (!(net->ipv6.sysctl.ip_nonlocal_bind ||

		      isk->freebind || isk->transparent || has_addr ||

		      addr_type == IPV6_ADDR_ANY))

			return -EADDRNOTAVAIL;

net/ipv6/af_inet6.c

+2 −1
Original line number Diff line number Diff line
@@ -342,7 +342,8 @@ int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 
			 */

			v4addr = LOOPBACK4_IPV6;

			if (!(addr_type & IPV6_ADDR_MULTICAST))	{

				if (!(inet->freebind || inet->transparent) &&

				if (!net->ipv6.sysctl.ip_nonlocal_bind &&

				    !(inet->freebind || inet->transparent) &&

				    !ipv6_chk_addr(net, &addr->sin6_addr,

						   dev, 0)) {

					err = -EADDRNOTAVAIL;

net/ipv6/raw.c

+2 −1
Original line number Diff line number Diff line
@@ -295,7 +295,8 @@ static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 
		 * unspecified and mapped address have a v4 equivalent.

		 */

		v4addr = LOOPBACK4_IPV6;

		if (!(addr_type & IPV6_ADDR_MULTICAST))	{

		if (!(addr_type & IPV6_ADDR_MULTICAST) &&

		    !sock_net(sk)->ipv6.sysctl.ip_nonlocal_bind) {

			err = -EADDRNOTAVAIL;

			if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr,

					   dev, 0)) {

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