ipv4: AF_INET link address family

Implements the AF_INET link address family exposing the per
device configuration settings via netlink using the attribute
IFLA_INET_CONF.

The format of IFLA_INET_CONF differs depending on the direction
the attribute is sent. The attribute sent by the kernel consists
of a u32 array, basically a 1:1 copy of in_device->cnf.data[].
The attribute expected by the kernel must consist of a sequence
of nested u32 attributes, each representing a change request,
e.g.
	[IFLA_INET_CONF] = {
		[IPV4_DEVCONF_FORWARDING] = 1,
		[IPV4_DEVCONF_NOXFRM] = 0,
	}

libnl userspace API documentation and example available from:
http://www.infradead.org/~tgr/libnl/doc-git/group__link__inet.html

Signed-off-by: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Thomas Graf 2010-11-16 04:32:48 +00:00 committed by David S. Miller
parent ca7479ebbd
commit 9f0f7272ac
2 changed files with 83 additions and 0 deletions

View File

@ -147,6 +147,14 @@ enum {
#define IFLA_PAYLOAD(n) NLMSG_PAYLOAD(n,sizeof(struct ifinfomsg))
#endif
enum {
IFLA_INET_UNSPEC,
IFLA_INET_CONF,
__IFLA_INET_MAX,
};
#define IFLA_INET_MAX (__IFLA_INET_MAX - 1)
/* ifi_flags.
IFF_* flags.

View File

@ -1256,6 +1256,72 @@ errout:
rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
}
static size_t inet_get_link_af_size(const struct net_device *dev)
{
struct in_device *in_dev = __in_dev_get_rcu(dev);
if (!in_dev)
return 0;
return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
}
static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
{
struct in_device *in_dev = __in_dev_get_rcu(dev);
struct nlattr *nla;
int i;
if (!in_dev)
return -ENODATA;
nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
if (nla == NULL)
return -EMSGSIZE;
for (i = 0; i < IPV4_DEVCONF_MAX; i++)
((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
return 0;
}
static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
[IFLA_INET_CONF] = { .type = NLA_NESTED },
};
static int inet_parse_link_af(struct net_device *dev, const struct nlattr *nla)
{
struct in_device *in_dev = __in_dev_get_rcu(dev);
struct nlattr *a, *tb[IFLA_INET_MAX+1];
int err, rem;
if (!in_dev)
return -EOPNOTSUPP;
err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
if (err < 0)
return err;
if (tb[IFLA_INET_CONF]) {
nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
int cfgid = nla_type(a);
if (nla_len(a) < 4)
return -EINVAL;
if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
return -EINVAL;
}
}
if (tb[IFLA_INET_CONF]) {
nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
}
return 0;
}
#ifdef CONFIG_SYSCTL
static void devinet_copy_dflt_conf(struct net *net, int i)
@ -1619,6 +1685,13 @@ static __net_initdata struct pernet_operations devinet_ops = {
.exit = devinet_exit_net,
};
static struct rtnl_af_ops inet_af_ops = {
.family = AF_INET,
.fill_link_af = inet_fill_link_af,
.get_link_af_size = inet_get_link_af_size,
.parse_link_af = inet_parse_link_af,
};
void __init devinet_init(void)
{
register_pernet_subsys(&devinet_ops);
@ -1626,6 +1699,8 @@ void __init devinet_init(void)
register_gifconf(PF_INET, inet_gifconf);
register_netdevice_notifier(&ip_netdev_notifier);
rtnl_af_register(&inet_af_ops);
rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL);
rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL);
rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr);