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: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert 2015-07-08 16:58:22 -07:00 committed by David S. Miller
parent 5a10ececc6
commit 35a256fee5
6 changed files with 20 additions and 3 deletions

View File

@ -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.

View File

@ -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;

View File

@ -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;

View File

@ -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;

View File

@ -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)) {

View File

@ -75,6 +75,13 @@ static struct ctl_table ipv6_table_template[] = {
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "ip_nonlocal_bind",
.data = &init_net.ipv6.sysctl.ip_nonlocal_bind,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{ }
};
@ -117,6 +124,7 @@ static int __net_init ipv6_sysctl_net_init(struct net *net)
ipv6_table[5].data = &net->ipv6.sysctl.idgen_retries;
ipv6_table[6].data = &net->ipv6.sysctl.idgen_delay;
ipv6_table[7].data = &net->ipv6.sysctl.flowlabel_state_ranges;
ipv6_table[8].data = &net->ipv6.sysctl.ip_nonlocal_bind;
ipv6_route_table = ipv6_route_sysctl_init(net);
if (!ipv6_route_table)