From caeaba79009c2ee858c3b2bf8caf922cd719fead Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel Date: Thu, 16 May 2013 22:32:00 +0000 Subject: [PATCH] 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: Nicolas Dichtel Signed-off-by: David S. Miller --- include/net/if_inet6.h | 1 + net/ipv6/addrconf.c | 64 +++++++++++++++++++++++++++++++----------- 2 files changed, 48 insertions(+), 17 deletions(-) diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h index 100fb8cec17c..0727d0e4af3b 100644 --- a/include/net/if_inet6.h +++ b/include/net/if_inet6.h @@ -74,6 +74,7 @@ struct inet6_ifaddr { bool tokenized; struct rcu_head rcu; + struct in6_addr peer_addr; }; struct ip6_sf_socklist { diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index d1ab6ab29a55..d684d23bc027 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -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(); @@ -3610,18 +3613,20 @@ 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 - pfx = nla_data(local); + *peer_pfx = pfx; + pfx = nla_data(local); } return pfx; @@ -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))