1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_IP6_ROUTE_H
3 #define _NET_IP6_ROUTE_H
5 #include <net/addrconf.h>
7 #include <net/ip6_fib.h>
9 #include <net/lwtunnel.h>
11 #include <linux/ipv6.h>
12 #include <linux/route.h>
13 #include <net/nexthop.h>
19 #if defined(__BIG_ENDIAN_BITFIELD)
23 #elif defined(__LITTLE_ENDIAN_BITFIELD)
29 __u8 prefix[]; /* 0,8 or 16 */
32 #define RT6_LOOKUP_F_IFACE 0x00000001
33 #define RT6_LOOKUP_F_REACHABLE 0x00000002
34 #define RT6_LOOKUP_F_HAS_SADDR 0x00000004
35 #define RT6_LOOKUP_F_SRCPREF_TMP 0x00000008
36 #define RT6_LOOKUP_F_SRCPREF_PUBLIC 0x00000010
37 #define RT6_LOOKUP_F_SRCPREF_COA 0x00000020
38 #define RT6_LOOKUP_F_IGNORE_LINKSTATE 0x00000040
39 #define RT6_LOOKUP_F_DST_NOREF 0x00000080
41 /* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
42 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
44 #define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
47 * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
48 * between IPV6_ADDR_PREFERENCES socket option values
49 * IPV6_PREFER_SRC_TMP = 0x1
50 * IPV6_PREFER_SRC_PUBLIC = 0x2
51 * IPV6_PREFER_SRC_COA = 0x4
52 * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
54 static inline int rt6_srcprefs2flags(unsigned int srcprefs)
56 return (srcprefs & IPV6_PREFER_SRC_MASK) << 3;
59 static inline unsigned int rt6_flags2srcprefs(int flags)
61 return (flags >> 3) & IPV6_PREFER_SRC_MASK;
64 static inline bool rt6_need_strict(const struct in6_addr *daddr)
66 return ipv6_addr_type(daddr) &
67 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
70 /* fib entries using a nexthop object can not be coalesced into
73 static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i)
75 /* the RTF_ADDRCONF flag filters out RA's */
76 return !(f6i->fib6_flags & RTF_ADDRCONF) && !f6i->nh &&
77 f6i->fib6_nh->fib_nh_gw_family;
80 void ip6_route_input(struct sk_buff *skb);
81 struct dst_entry *ip6_route_input_lookup(struct net *net,
82 struct net_device *dev,
84 const struct sk_buff *skb, int flags);
86 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
87 struct flowi6 *fl6, int flags);
89 static inline struct dst_entry *ip6_route_output(struct net *net,
90 const struct sock *sk,
93 return ip6_route_output_flags(net, sk, fl6, 0);
96 /* Only conditionally release dst if flags indicates
97 * !RT6_LOOKUP_F_DST_NOREF or dst is in uncached_list.
99 static inline void ip6_rt_put_flags(struct rt6_info *rt, int flags)
101 if (!(flags & RT6_LOOKUP_F_DST_NOREF) ||
102 !list_empty(&rt->dst.rt_uncached))
106 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
107 const struct sk_buff *skb, int flags);
108 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
109 int ifindex, struct flowi6 *fl6,
110 const struct sk_buff *skb, int flags);
112 void ip6_route_init_special_entries(void);
113 int ip6_route_init(void);
114 void ip6_route_cleanup(void);
116 int ipv6_route_ioctl(struct net *net, unsigned int cmd,
117 struct in6_rtmsg *rtmsg);
119 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
120 struct netlink_ext_ack *extack);
121 int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
122 int ip6_del_rt(struct net *net, struct fib6_info *f6i, bool skip_notify);
124 void rt6_flush_exceptions(struct fib6_info *f6i);
125 void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
128 static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i,
129 const struct in6_addr *daddr,
131 struct in6_addr *saddr)
135 if (f6i && f6i->fib6_prefsrc.plen) {
136 *saddr = f6i->fib6_prefsrc.addr;
138 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL;
140 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr);
146 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
147 const struct in6_addr *saddr, int oif,
148 const struct sk_buff *skb, int flags);
149 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
150 const struct sk_buff *skb, struct flow_keys *hkeys);
152 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
154 void fib6_force_start_gc(struct net *net);
156 struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev,
157 const struct in6_addr *addr, bool anycast,
158 gfp_t gfp_flags, struct netlink_ext_ack *extack);
160 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
164 * support functions for ND
167 struct fib6_info *rt6_get_dflt_router(struct net *net,
168 const struct in6_addr *addr,
169 struct net_device *dev);
170 struct fib6_info *rt6_add_dflt_router(struct net *net,
171 const struct in6_addr *gwaddr,
172 struct net_device *dev, unsigned int pref,
173 u32 defrtr_usr_metric);
175 void rt6_purge_dflt_routers(struct net *net);
177 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
178 const struct in6_addr *gwaddr);
180 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
181 u32 mark, kuid_t uid);
182 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
183 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
185 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif);
186 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
188 struct netlink_callback;
190 struct rt6_rtnl_dump_arg {
192 struct netlink_callback *cb;
194 struct fib_dump_filter filter;
197 int rt6_dump_route(struct fib6_info *f6i, void *p_arg, unsigned int skip);
198 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
199 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
200 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
201 void rt6_sync_up(struct net_device *dev, unsigned char nh_flags);
202 void rt6_disable_ip(struct net_device *dev, unsigned long event);
203 void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
204 void rt6_multipath_rebalance(struct fib6_info *f6i);
206 void rt6_uncached_list_add(struct rt6_info *rt);
207 void rt6_uncached_list_del(struct rt6_info *rt);
209 static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
211 const struct dst_entry *dst = skb_dst(skb);
212 const struct rt6_info *rt6 = NULL;
215 rt6 = container_of(dst, struct rt6_info, dst);
221 * Store a destination cache entry in a socket
223 static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
224 const struct in6_addr *daddr,
225 const struct in6_addr *saddr)
227 struct ipv6_pinfo *np = inet6_sk(sk);
229 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
230 sk_setup_caps(sk, dst);
231 np->daddr_cache = daddr;
232 #ifdef CONFIG_IPV6_SUBTREES
233 np->saddr_cache = saddr;
237 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
238 const struct flowi6 *fl6);
240 static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
242 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
244 return rt->rt6i_flags & RTF_LOCAL;
247 static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
248 const struct in6_addr *daddr)
250 struct rt6_info *rt = (struct rt6_info *)dst;
252 return rt->rt6i_flags & RTF_ANYCAST ||
253 (rt->rt6i_dst.plen < 127 &&
254 !(rt->rt6i_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) &&
255 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
258 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
259 int (*output)(struct net *, struct sock *, struct sk_buff *));
261 static inline unsigned int ip6_skb_dst_mtu(const struct sk_buff *skb)
263 const struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
264 inet6_sk(skb->sk) : NULL;
265 const struct dst_entry *dst = skb_dst(skb);
268 if (np && READ_ONCE(np->pmtudisc) >= IPV6_PMTUDISC_PROBE) {
269 mtu = READ_ONCE(dst->dev->mtu);
270 mtu -= lwtunnel_headroom(dst->lwtstate, mtu);
277 static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
279 u8 pmtudisc = READ_ONCE(inet6_sk(sk)->pmtudisc);
281 return pmtudisc != IPV6_PMTUDISC_INTERFACE &&
282 pmtudisc != IPV6_PMTUDISC_OMIT;
285 static inline bool ip6_sk_ignore_df(const struct sock *sk)
287 u8 pmtudisc = READ_ONCE(inet6_sk(sk)->pmtudisc);
289 return pmtudisc < IPV6_PMTUDISC_DO ||
290 pmtudisc == IPV6_PMTUDISC_OMIT;
293 static inline const struct in6_addr *rt6_nexthop(const struct rt6_info *rt,
294 const struct in6_addr *daddr)
296 if (rt->rt6i_flags & RTF_GATEWAY)
297 return &rt->rt6i_gateway;
298 else if (unlikely(rt->rt6i_flags & RTF_CACHE))
299 return &rt->rt6i_dst.addr;
304 static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b)
306 struct fib6_nh *nha, *nhb;
309 return nexthop_cmp(a->nh, b->nh);
313 return nha->fib_nh_dev == nhb->fib_nh_dev &&
314 ipv6_addr_equal(&nha->fib_nh_gw6, &nhb->fib_nh_gw6) &&
315 !lwtunnel_cmp_encap(nha->fib_nh_lws, nhb->fib_nh_lws);
318 static inline unsigned int ip6_dst_mtu_maybe_forward(const struct dst_entry *dst,
321 struct inet6_dev *idev;
324 if (!forwarding || dst_metric_locked(dst, RTAX_MTU)) {
325 mtu = dst_metric_raw(dst, RTAX_MTU);
332 idev = __in6_dev_get(dst->dev);
334 mtu = idev->cnf.mtu6;
338 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
341 u32 ip6_mtu_from_fib6(const struct fib6_result *res,
342 const struct in6_addr *daddr,
343 const struct in6_addr *saddr);
345 struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
346 struct net_device *dev, struct sk_buff *skb,