#include <net/xfrm.h>
#include <net/netevent.h>
#include <net/netlink.h>
+#include <net/nexthop.h>
#include <asm/uaccess.h>
memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers);
rt->rt6i_genid = rt_genid(net);
+ INIT_LIST_HEAD(&rt->rt6i_siblings);
+ rt->rt6i_nsiblings = 0;
}
return rt;
}
(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
}
+/* Multipath route selection:
+ * Hash based function using packet header and flowlabel.
+ * Adapted from fib_info_hashfn()
+ */
+static int rt6_info_hash_nhsfn(unsigned int candidate_count,
+ const struct flowi6 *fl6)
+{
+ unsigned int val = fl6->flowi6_proto;
+
+ val ^= (__force u32)fl6->daddr.s6_addr32[0];
+ val ^= (__force u32)fl6->daddr.s6_addr32[1];
+ val ^= (__force u32)fl6->daddr.s6_addr32[2];
+ val ^= (__force u32)fl6->daddr.s6_addr32[3];
+
+ val ^= (__force u32)fl6->saddr.s6_addr32[0];
+ val ^= (__force u32)fl6->saddr.s6_addr32[1];
+ val ^= (__force u32)fl6->saddr.s6_addr32[2];
+ val ^= (__force u32)fl6->saddr.s6_addr32[3];
+
+ /* Work only if this not encapsulated */
+ switch (fl6->flowi6_proto) {
+ case IPPROTO_UDP:
+ case IPPROTO_TCP:
+ case IPPROTO_SCTP:
+ val ^= (__force u16)fl6->fl6_sport;
+ val ^= (__force u16)fl6->fl6_dport;
+ break;
+
+ case IPPROTO_ICMPV6:
+ val ^= (__force u16)fl6->fl6_icmp_type;
+ val ^= (__force u16)fl6->fl6_icmp_code;
+ break;
+ }
+ /* RFC6438 recommands to use flowlabel */
+ val ^= (__force u32)fl6->flowlabel;
+
+ /* Perhaps, we need to tune, this function? */
+ val = val ^ (val >> 7) ^ (val >> 12);
+ return val % candidate_count;
+}
+
+static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
+ struct flowi6 *fl6)
+{
+ struct rt6_info *sibling, *next_sibling;
+ int route_choosen;
+
+ route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
+ /* Don't change the route, if route_choosen == 0
+ * (siblings does not include ourself)
+ */
+ if (route_choosen)
+ list_for_each_entry_safe(sibling, next_sibling,
+ &match->rt6i_siblings, rt6i_siblings) {
+ route_choosen--;
+ if (route_choosen == 0) {
+ match = sibling;
+ break;
+ }
+ }
+ return match;
+}
+
/*
* Route lookup. Any table->tb6_lock is implied.
*/
else
rt6_set_expires(rt, jiffies + HZ * lifetime);
- dst_release(&rt->dst);
+ ip6_rt_put(rt);
}
return 0;
}
restart:
rt = fn->leaf;
rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
+ if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
+ rt = rt6_multipath_select(rt, fl6);
BACKTRACK(net, &fl6->saddr);
out:
dst_use(&rt->dst, jiffies);
restart:
rt = rt6_select(fn, oif, strict | reachable);
-
+ if (rt->rt6i_nsiblings && oif == 0)
+ rt = rt6_multipath_select(rt, fl6);
BACKTRACK(net, &fl6->saddr);
if (rt == net->ipv6.ip6_null_entry ||
rt->rt6i_flags & RTF_CACHE)
else
goto out2;
- dst_release(&rt->dst);
+ ip6_rt_put(rt);
rt = nrt ? : net->ipv6.ip6_null_entry;
dst_hold(&rt->dst);
* Race condition! In the gap, when table->tb6_lock was
* released someone could insert this route. Relookup.
*/
- dst_release(&rt->dst);
+ ip6_rt_put(rt);
goto relookup;
out:
goto out;
if (dev) {
if (dev != grt->dst.dev) {
- dst_release(&grt->dst);
+ ip6_rt_put(grt);
goto out;
}
} else {
}
if (!(grt->rt6i_flags & RTF_GATEWAY))
err = 0;
- dst_release(&grt->dst);
+ ip6_rt_put(grt);
if (err)
goto out;
write_unlock_bh(&table->tb6_lock);
out:
- dst_release(&rt->dst);
+ ip6_rt_put(rt);
return err;
}
[RTA_IIF] = { .type = NLA_U32 },
[RTA_PRIORITY] = { .type = NLA_U32 },
[RTA_METRICS] = { .type = NLA_NESTED },
+ [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
};
static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
if (tb[RTA_TABLE])
cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
+ if (tb[RTA_MULTIPATH]) {
+ cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
+ cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
+ }
+
err = 0;
errout:
return err;
}
+static int ip6_route_multipath(struct fib6_config *cfg, int add)
+{
+ struct fib6_config r_cfg;
+ struct rtnexthop *rtnh;
+ int remaining;
+ int attrlen;
+ int err = 0, last_err = 0;
+
+beginning:
+ rtnh = (struct rtnexthop *)cfg->fc_mp;
+ remaining = cfg->fc_mp_len;
+
+ /* Parse a Multipath Entry */
+ while (rtnh_ok(rtnh, remaining)) {
+ memcpy(&r_cfg, cfg, sizeof(*cfg));
+ if (rtnh->rtnh_ifindex)
+ r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
+
+ attrlen = rtnh_attrlen(rtnh);
+ if (attrlen > 0) {
+ struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
+
+ nla = nla_find(attrs, attrlen, RTA_GATEWAY);
+ if (nla) {
+ nla_memcpy(&r_cfg.fc_gateway, nla, 16);
+ r_cfg.fc_flags |= RTF_GATEWAY;
+ }
+ }
+ err = add ? ip6_route_add(&r_cfg) : ip6_route_del(&r_cfg);
+ if (err) {
+ last_err = err;
+ /* If we are trying to remove a route, do not stop the
+ * loop when ip6_route_del() fails (because next hop is
+ * already gone), we should try to remove all next hops.
+ */
+ if (add) {
+ /* If add fails, we should try to delete all
+ * next hops that have been already added.
+ */
+ add = 0;
+ goto beginning;
+ }
+ }
+ /* Because each route is added like a single route we remove
+ * this flag after the first nexthop (if there is a collision,
+ * we have already fail to add the first nexthop:
+ * fib6_add_rt2node() has reject it).
+ */
+ cfg->fc_nlinfo.nlh->nlmsg_flags &= ~NLM_F_EXCL;
+ rtnh = rtnh_next(rtnh, &remaining);
+ }
+
+ return last_err;
+}
+
static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct fib6_config cfg;
if (err < 0)
return err;
- return ip6_route_del(&cfg);
+ if (cfg.fc_mp)
+ return ip6_route_multipath(&cfg, 0);
+ else
+ return ip6_route_del(&cfg);
}
static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
if (err < 0)
return err;
- return ip6_route_add(&cfg);
+ if (cfg.fc_mp)
+ return ip6_route_multipath(&cfg, 1);
+ else
+ return ip6_route_add(&cfg);
}
static inline size_t rt6_nlmsg_size(void)
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
if (!skb) {
- dst_release(&rt->dst);
+ ip6_rt_put(rt);
err = -ENOBUFS;
goto errout;
}