From 70ceb4f53929f73746be72f73707cd9f8753e2fc Mon Sep 17 00:00:00 2001 From: YOSHIFUJI Hideaki Date: Mon, 20 Mar 2006 17:06:24 -0800 Subject: [PATCH] [IPV6]: ROUTE: Add experimental support for Route Information Option in RA (RFC4191). Signed-off-by: YOSHIFUJI Hideaki Signed-off-by: David S. Miller --- include/linux/ipv6_route.h | 2 + include/net/ip6_route.h | 21 ++++++ include/net/ndisc.h | 2 + net/ipv6/Kconfig | 8 +++ net/ipv6/ndisc.c | 25 ++++++- net/ipv6/route.c | 134 +++++++++++++++++++++++++++++++++++++ 6 files changed, 191 insertions(+), 1 deletion(-) diff --git a/include/linux/ipv6_route.h b/include/linux/ipv6_route.h index f4b085c91608..b323ff577967 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 50161322b828..a398ae5e30f9 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 @@ -92,6 +109,10 @@ extern struct rt6_info * rt6_add_dflt_router(struct in6_addr *gwaddr, 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 bbac87eeb422..91fa271a0064 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -22,6 +22,8 @@ enum { 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 c456ead8a4a3..e6f83b6a2b76 100644 --- a/net/ipv6/Kconfig +++ b/net/ipv6/Kconfig @@ -49,6 +49,14 @@ config IPV6_ROUTER_PREF 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 f4462ee33024..1f6256909674 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -156,7 +156,11 @@ struct neigh_table nd_tbl = { /* 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 @@ static struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len, 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 @@ static void ndisc_router_discovery(struct sk_buff *skb) 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 c797b9bbb7d1..0f30ee3d94ea 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -98,6 +98,14 @@ static int ip6_pkt_discard_out(struct sk_buff *skb); 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 @@ static struct rt6_info *rt6_select(struct rt6_info **head, int oif, 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 @@ static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) 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; -- GitLab