[IPV6]: ROUTE: Add experimental support for Route Information Option in RA (RFC4191).
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ipv6_route.h b/include/linux/ipv6_route.h
index f4b085c..b323ff5 100644
--- a/include/linux/ipv6_route.h
+++ b/include/linux/ipv6_route.h
@@ -23,6 +23,8 @@
#define RTF_NONEXTHOP 0x00200000 /* route with no nexthop */
#define RTF_EXPIRES 0x00400000
+#define RTF_ROUTEINFO 0x00800000 /* route information - RA */
+
#define RTF_CACHE 0x01000000 /* cache entry */
#define RTF_FLOW 0x02000000 /* flow significant route */
#define RTF_POLICY 0x04000000 /* policy route */
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 5016132..a398ae5 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -7,6 +7,23 @@
#define IP6_RT_PRIO_KERN 512
#define IP6_RT_FLOW_MASK 0x00ff
+struct route_info {
+ __u8 type;
+ __u8 length;
+ __u8 prefix_len;
+#if defined(__BIG_ENDIAN_BITFIELD)
+ __u8 reserved_h:3,
+ route_pref:2,
+ reserved_l:3;
+#elif defined(__LITTLE_ENDIAN_BITFIELD)
+ __u8 reserved_l:3,
+ route_pref:2,
+ reserved_h:3;
+#endif
+ __u32 lifetime;
+ __u8 prefix[0]; /* 0,8 or 16 */
+};
+
#ifdef __KERNEL__
#include <net/flow.h>
@@ -92,6 +109,10 @@
extern void rt6_purge_dflt_routers(void);
+extern int rt6_route_rcv(struct net_device *dev,
+ u8 *opt, int len,
+ struct in6_addr *gwaddr);
+
extern void rt6_redirect(struct in6_addr *dest,
struct in6_addr *saddr,
struct neighbour *neigh,
diff --git a/include/net/ndisc.h b/include/net/ndisc.h
index bbac87e..91fa271 100644
--- a/include/net/ndisc.h
+++ b/include/net/ndisc.h
@@ -22,6 +22,8 @@
ND_OPT_PREFIX_INFO = 3, /* RFC2461 */
ND_OPT_REDIRECT_HDR = 4, /* RFC2461 */
ND_OPT_MTU = 5, /* RFC2461 */
+ __ND_OPT_ARRAY_MAX,
+ ND_OPT_ROUTE_INFO = 24, /* RFC4191 */
__ND_OPT_MAX
};
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index c456ead..e6f83b6 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -49,6 +49,14 @@
If unsure, say N.
+config IPV6_ROUTE_INFO
+ bool "IPv6: Route Information (RFC 4191) support (EXPERIMENTAL)"
+ depends on IPV6_ROUTER_PREF && EXPERIMENTAL
+ ---help---
+ This is experimental support of Route Information.
+
+ If unsure, say N.
+
config INET6_AH
tristate "IPv6: AH transformation"
depends on IPV6
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index f4462ee..1f62569 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -156,7 +156,11 @@
/* ND options */
struct ndisc_options {
- struct nd_opt_hdr *nd_opt_array[__ND_OPT_MAX];
+ struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX];
+#ifdef CONFIG_IPV6_ROUTE_INFO
+ struct nd_opt_hdr *nd_opts_ri;
+ struct nd_opt_hdr *nd_opts_ri_end;
+#endif
};
#define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR]
@@ -255,6 +259,13 @@
if (ndopts->nd_opt_array[nd_opt->nd_opt_type] == 0)
ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
break;
+#ifdef CONFIG_IPV6_ROUTE_INFO
+ case ND_OPT_ROUTE_INFO:
+ ndopts->nd_opts_ri_end = nd_opt;
+ if (!ndopts->nd_opts_ri)
+ ndopts->nd_opts_ri = nd_opt;
+ break;
+#endif
default:
/*
* Unknown options must be silently ignored,
@@ -1202,6 +1213,18 @@
NEIGH_UPDATE_F_ISROUTER);
}
+#ifdef CONFIG_IPV6_ROUTE_INFO
+ if (ndopts.nd_opts_ri) {
+ struct nd_opt_hdr *p;
+ for (p = ndopts.nd_opts_ri;
+ p;
+ p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
+ rt6_route_rcv(skb->dev, (u8*)p, (p->nd_opt_len) << 3,
+ &skb->nh.ipv6h->saddr);
+ }
+ }
+#endif
+
if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
struct nd_opt_hdr *p;
for (p = ndopts.nd_opts_pi;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index c797b9b..0f30ee3 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -98,6 +98,14 @@
static void ip6_link_failure(struct sk_buff *skb);
static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
+#ifdef CONFIG_IPV6_ROUTE_INFO
+static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
+ struct in6_addr *gwaddr, int ifindex,
+ unsigned pref);
+static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
+ struct in6_addr *gwaddr, int ifindex);
+#endif
+
static struct dst_ops ip6_dst_ops = {
.family = AF_INET6,
.protocol = __constant_htons(ETH_P_IPV6),
@@ -346,6 +354,84 @@
return (match ? match : &ip6_null_entry);
}
+#ifdef CONFIG_IPV6_ROUTE_INFO
+int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
+ struct in6_addr *gwaddr)
+{
+ struct route_info *rinfo = (struct route_info *) opt;
+ struct in6_addr prefix_buf, *prefix;
+ unsigned int pref;
+ u32 lifetime;
+ struct rt6_info *rt;
+
+ if (len < sizeof(struct route_info)) {
+ return -EINVAL;
+ }
+
+ /* Sanity check for prefix_len and length */
+ if (rinfo->length > 3) {
+ return -EINVAL;
+ } else if (rinfo->prefix_len > 128) {
+ return -EINVAL;
+ } else if (rinfo->prefix_len > 64) {
+ if (rinfo->length < 2) {
+ return -EINVAL;
+ }
+ } else if (rinfo->prefix_len > 0) {
+ if (rinfo->length < 1) {
+ return -EINVAL;
+ }
+ }
+
+ pref = rinfo->route_pref;
+ if (pref == ICMPV6_ROUTER_PREF_INVALID)
+ pref = ICMPV6_ROUTER_PREF_MEDIUM;
+
+ lifetime = htonl(rinfo->lifetime);
+ if (lifetime == 0xffffffff) {
+ /* infinity */
+ } else if (lifetime > 0x7fffffff/HZ) {
+ /* Avoid arithmetic overflow */
+ lifetime = 0x7fffffff/HZ - 1;
+ }
+
+ if (rinfo->length == 3)
+ prefix = (struct in6_addr *)rinfo->prefix;
+ else {
+ /* this function is safe */
+ ipv6_addr_prefix(&prefix_buf,
+ (struct in6_addr *)rinfo->prefix,
+ rinfo->prefix_len);
+ prefix = &prefix_buf;
+ }
+
+ rt = rt6_get_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex);
+
+ if (rt && !lifetime) {
+ ip6_del_rt(rt, NULL, NULL, NULL);
+ rt = NULL;
+ }
+
+ if (!rt && lifetime)
+ rt = rt6_add_route_info(prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
+ pref);
+ else if (rt)
+ rt->rt6i_flags = RTF_ROUTEINFO |
+ (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
+
+ if (rt) {
+ if (lifetime == 0xffffffff) {
+ rt->rt6i_flags &= ~RTF_EXPIRES;
+ } else {
+ rt->rt6i_expires = jiffies + HZ * lifetime;
+ rt->rt6i_flags |= RTF_EXPIRES;
+ }
+ dst_release(&rt->u.dst);
+ }
+ return 0;
+}
+#endif
+
struct rt6_info *rt6_lookup(struct in6_addr *daddr, struct in6_addr *saddr,
int oif, int strict)
{
@@ -1277,6 +1363,54 @@
return rt;
}
+#ifdef CONFIG_IPV6_ROUTE_INFO
+static struct rt6_info *rt6_get_route_info(struct in6_addr *prefix, int prefixlen,
+ struct in6_addr *gwaddr, int ifindex)
+{
+ struct fib6_node *fn;
+ struct rt6_info *rt = NULL;
+
+ write_lock_bh(&rt6_lock);
+ fn = fib6_locate(&ip6_routing_table, prefix ,prefixlen, NULL, 0);
+ if (!fn)
+ goto out;
+
+ for (rt = fn->leaf; rt; rt = rt->u.next) {
+ if (rt->rt6i_dev->ifindex != ifindex)
+ continue;
+ if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
+ continue;
+ if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
+ continue;
+ dst_hold(&rt->u.dst);
+ break;
+ }
+out:
+ write_unlock_bh(&rt6_lock);
+ return rt;
+}
+
+static struct rt6_info *rt6_add_route_info(struct in6_addr *prefix, int prefixlen,
+ struct in6_addr *gwaddr, int ifindex,
+ unsigned pref)
+{
+ struct in6_rtmsg rtmsg;
+
+ memset(&rtmsg, 0, sizeof(rtmsg));
+ rtmsg.rtmsg_type = RTMSG_NEWROUTE;
+ ipv6_addr_copy(&rtmsg.rtmsg_dst, prefix);
+ rtmsg.rtmsg_dst_len = prefixlen;
+ ipv6_addr_copy(&rtmsg.rtmsg_gateway, gwaddr);
+ rtmsg.rtmsg_metric = 1024;
+ rtmsg.rtmsg_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO | RTF_UP | RTF_PREF(pref);
+ rtmsg.rtmsg_ifindex = ifindex;
+
+ ip6_route_add(&rtmsg, NULL, NULL, NULL);
+
+ return rt6_get_route_info(prefix, prefixlen, gwaddr, ifindex);
+}
+#endif
+
struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev)
{
struct rt6_info *rt;