Commit caeaba79 authored by Nicolas Dichtel's avatar Nicolas Dichtel Committed by David S. Miller
Browse files

ipv6: add support of peer address 



This patch adds the support of peer address for IPv6. For example, it is
possible to specify the remote end of a 6inY tunnel.
This was already possible in IPv4:
 ip addr add ip1 peer ip2 dev dev1

The peer address is specified with IFA_ADDRESS and the local address with
IFA_LOCAL (like explained in include/uapi/linux/if_addr.h).
Note that the API is not changed, because before this patch, it was not
possible to specify two different addresses in IFA_LOCAL and IFA_REMOTE.
There is a small change for the dump: if the peer is different from ::,
IFA_ADDRESS will contain the peer address instead of the local address.

Signed-off-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5199dfe5

include/net/if_inet6.h

+1 −0
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ struct inet6_ifaddr { 
	bool			tokenized;



	struct rcu_head		rcu;

	struct in6_addr		peer_addr;

};



struct ip6_sf_socklist {

net/ipv6/addrconf.c

+47 −17
Original line number Diff line number Diff line
@@ -2402,6 +2402,7 @@ err_exit: 
 *	Manual configuration of address on an interface

 */

static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,

			  const struct in6_addr *peer_pfx,

			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,

			  __u32 valid_lft)

{
@@ -2457,6 +2458,8 @@ static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *p 
		ifp->valid_lft = valid_lft;

		ifp->prefered_lft = prefered_lft;

		ifp->tstamp = jiffies;

		if (peer_pfx)

			ifp->peer_addr = *peer_pfx;

		spin_unlock_bh(&ifp->lock);



		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
@@ -2526,7 +2529,7 @@ int addrconf_add_ifaddr(struct net *net, void __user *arg) 
		return -EFAULT;



	rtnl_lock();

	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,

	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr, NULL,

			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,

			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);

	rtnl_unlock();
@@ -3610,17 +3613,19 @@ restart: 
	rcu_read_unlock_bh();

}



static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)

static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,

				     struct in6_addr **peer_pfx)

{

	struct in6_addr *pfx = NULL;



	*peer_pfx = NULL;



	if (addr)

		pfx = nla_data(addr);



	if (local) {

		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))

			pfx = NULL;

		else

			*peer_pfx = pfx;

		pfx = nla_data(local);

	}
@@ -3639,7 +3644,7 @@ inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh) 
	struct net *net = sock_net(skb->sk);

	struct ifaddrmsg *ifm;

	struct nlattr *tb[IFA_MAX+1];

	struct in6_addr *pfx;

	struct in6_addr *pfx, *peer_pfx;

	int err;



	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
@@ -3647,7 +3652,7 @@ inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh) 
		return err;



	ifm = nlmsg_data(nlh);

	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);

	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);

	if (pfx == NULL)

		return -EINVAL;
@@ -3705,7 +3710,7 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh) 
	struct net *net = sock_net(skb->sk);

	struct ifaddrmsg *ifm;

	struct nlattr *tb[IFA_MAX+1];

	struct in6_addr *pfx;

	struct in6_addr *pfx, *peer_pfx;

	struct inet6_ifaddr *ifa;

	struct net_device *dev;

	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
@@ -3717,7 +3722,7 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh) 
		return err;



	ifm = nlmsg_data(nlh);

	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);

	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);

	if (pfx == NULL)

		return -EINVAL;
@@ -3745,7 +3750,7 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh) 
		 * It would be best to check for !NLM_F_CREATE here but

		 * userspace alreay relies on not having to provide this.

		 */

		return inet6_addr_add(net, ifm->ifa_index, pfx,

		return inet6_addr_add(net, ifm->ifa_index, pfx, peer_pfx,

				      ifm->ifa_prefixlen, ifa_flags,

				      preferred_lft, valid_lft);

	}
@@ -3802,6 +3807,7 @@ static inline int rt_scope(int ifa_scope) 
static inline int inet6_ifaddr_msgsize(void)

{

	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))

	       + nla_total_size(16) /* IFA_LOCAL */

	       + nla_total_size(16) /* IFA_ADDRESS */

	       + nla_total_size(sizeof(struct ifa_cacheinfo));

}
@@ -3840,13 +3846,22 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa, 
		valid = INFINITY_LIFE_TIME;

	}



	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||

	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {

		nlmsg_cancel(skb, nlh);

		return -EMSGSIZE;

	}

	if (ipv6_addr_type(&ifa->peer_addr) != IPV6_ADDR_ANY) {

		if (nla_put(skb, IFA_LOCAL, 16, &ifa->addr) < 0 ||

		    nla_put(skb, IFA_ADDRESS, 16, &ifa->peer_addr) < 0)

			goto error;

	} else

		if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0)

			goto error;



	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)

		goto error;



	return nlmsg_end(skb, nlh);



error:

	nlmsg_cancel(skb, nlh);

	return -EMSGSIZE;

}



static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
@@ -4046,7 +4061,7 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh) 
	struct net *net = sock_net(in_skb->sk);

	struct ifaddrmsg *ifm;

	struct nlattr *tb[IFA_MAX+1];

	struct in6_addr *addr = NULL;

	struct in6_addr *addr = NULL, *peer;

	struct net_device *dev = NULL;

	struct inet6_ifaddr *ifa;

	struct sk_buff *skb;
@@ -4056,7 +4071,7 @@ static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh) 
	if (err < 0)

		goto errout;



	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);

	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);

	if (addr == NULL) {

		err = -EINVAL;

		goto errout;
@@ -4564,11 +4579,26 @@ static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp) 
			ip6_ins_rt(ifp->rt);

		if (ifp->idev->cnf.forwarding)

			addrconf_join_anycast(ifp);

		if (ipv6_addr_type(&ifp->peer_addr) != IPV6_ADDR_ANY)

			addrconf_prefix_route(&ifp->peer_addr, 128,

					      ifp->idev->dev, 0, 0);

		break;

	case RTM_DELADDR:

		if (ifp->idev->cnf.forwarding)

			addrconf_leave_anycast(ifp);

		addrconf_leave_solict(ifp->idev, &ifp->addr);

		if (ipv6_addr_type(&ifp->peer_addr) != IPV6_ADDR_ANY) {

			struct rt6_info *rt;

			struct net_device *dev = ifp->idev->dev;



			rt = rt6_lookup(dev_net(dev), &ifp->peer_addr, NULL,

					dev->ifindex, 1);

			if (rt) {

				dst_hold(&rt->dst);

				if (ip6_del_rt(rt))

					dst_free(&rt->dst);

			}

		}

		dst_hold(&ifp->rt->dst);



		if (ip6_del_rt(ifp->rt))

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