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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NET_IP6_ROUTE_H
3#define _NET_IP6_ROUTE_H
4
5struct route_info {
6 __u8 type;
7 __u8 length;
8 __u8 prefix_len;
9#if defined(__BIG_ENDIAN_BITFIELD)
10 __u8 reserved_h:3,
11 route_pref:2,
12 reserved_l:3;
13#elif defined(__LITTLE_ENDIAN_BITFIELD)
14 __u8 reserved_l:3,
15 route_pref:2,
16 reserved_h:3;
17#endif
18 __be32 lifetime;
19 __u8 prefix[0]; /* 0,8 or 16 */
20};
21
22#include <net/addrconf.h>
23#include <net/flow.h>
24#include <net/ip6_fib.h>
25#include <net/sock.h>
26#include <net/lwtunnel.h>
27#include <linux/ip.h>
28#include <linux/ipv6.h>
29#include <linux/route.h>
30#include <net/nexthop.h>
31
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
40
41/* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
42 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
43 */
44#define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
45
46/*
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.
53 */
54static inline int rt6_srcprefs2flags(unsigned int srcprefs)
55{
56 /* No need to bitmask because srcprefs have only 3 bits. */
57 return srcprefs << 3;
58}
59
60static inline unsigned int rt6_flags2srcprefs(int flags)
61{
62 return (flags >> 3) & 7;
63}
64
65static inline bool rt6_need_strict(const struct in6_addr *daddr)
66{
67 return ipv6_addr_type(daddr) &
68 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
69}
70
71/* fib entries using a nexthop object can not be coalesced into
72 * a multipath route
73 */
74static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i)
75{
76 /* the RTF_ADDRCONF flag filters out RA's */
77 return !(f6i->fib6_flags & RTF_ADDRCONF) && !f6i->nh &&
78 f6i->fib6_nh->fib_nh_gw_family;
79}
80
81void ip6_route_input(struct sk_buff *skb);
82struct dst_entry *ip6_route_input_lookup(struct net *net,
83 struct net_device *dev,
84 struct flowi6 *fl6,
85 const struct sk_buff *skb, int flags);
86
87struct dst_entry *ip6_route_output_flags_noref(struct net *net,
88 const struct sock *sk,
89 struct flowi6 *fl6, int flags);
90
91struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
92 struct flowi6 *fl6, int flags);
93
94static inline struct dst_entry *ip6_route_output(struct net *net,
95 const struct sock *sk,
96 struct flowi6 *fl6)
97{
98 return ip6_route_output_flags(net, sk, fl6, 0);
99}
100
101/* Only conditionally release dst if flags indicates
102 * !RT6_LOOKUP_F_DST_NOREF or dst is in uncached_list.
103 */
104static inline void ip6_rt_put_flags(struct rt6_info *rt, int flags)
105{
106 if (!(flags & RT6_LOOKUP_F_DST_NOREF) ||
107 !list_empty(&rt->rt6i_uncached))
108 ip6_rt_put(rt);
109}
110
111struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
112 const struct sk_buff *skb, int flags);
113struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
114 int ifindex, struct flowi6 *fl6,
115 const struct sk_buff *skb, int flags);
116
117void ip6_route_init_special_entries(void);
118int ip6_route_init(void);
119void ip6_route_cleanup(void);
120
121int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
122
123int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
124 struct netlink_ext_ack *extack);
125int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
126int ip6_del_rt(struct net *net, struct fib6_info *f6i);
127
128void rt6_flush_exceptions(struct fib6_info *f6i);
129void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
130 unsigned long now);
131
132static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i,
133 const struct in6_addr *daddr,
134 unsigned int prefs,
135 struct in6_addr *saddr)
136{
137 int err = 0;
138
139 if (f6i && f6i->fib6_prefsrc.plen) {
140 *saddr = f6i->fib6_prefsrc.addr;
141 } else {
142 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL;
143
144 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr);
145 }
146
147 return err;
148}
149
150struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
151 const struct in6_addr *saddr, int oif,
152 const struct sk_buff *skb, int flags);
153u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
154 const struct sk_buff *skb, struct flow_keys *hkeys);
155
156struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
157
158void fib6_force_start_gc(struct net *net);
159
160struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev,
161 const struct in6_addr *addr, bool anycast,
162 gfp_t gfp_flags);
163
164struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
165 int flags);
166
167/*
168 * support functions for ND
169 *
170 */
171struct fib6_info *rt6_get_dflt_router(struct net *net,
172 const struct in6_addr *addr,
173 struct net_device *dev);
174struct fib6_info *rt6_add_dflt_router(struct net *net,
175 const struct in6_addr *gwaddr,
176 struct net_device *dev, unsigned int pref);
177
178void rt6_purge_dflt_routers(struct net *net);
179
180int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
181 const struct in6_addr *gwaddr);
182
183void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
184 u32 mark, kuid_t uid);
185void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
186void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
187 kuid_t uid);
188void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif);
189void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
190
191struct netlink_callback;
192
193struct rt6_rtnl_dump_arg {
194 struct sk_buff *skb;
195 struct netlink_callback *cb;
196 struct net *net;
197 struct fib_dump_filter filter;
198};
199
200int rt6_dump_route(struct fib6_info *f6i, void *p_arg, unsigned int skip);
201void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
202void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
203void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
204void rt6_sync_up(struct net_device *dev, unsigned char nh_flags);
205void rt6_disable_ip(struct net_device *dev, unsigned long event);
206void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
207void rt6_multipath_rebalance(struct fib6_info *f6i);
208
209void rt6_uncached_list_add(struct rt6_info *rt);
210void rt6_uncached_list_del(struct rt6_info *rt);
211
212static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
213{
214 const struct dst_entry *dst = skb_dst(skb);
215 const struct rt6_info *rt6 = NULL;
216
217 if (dst)
218 rt6 = container_of(dst, struct rt6_info, dst);
219
220 return rt6;
221}
222
223/*
224 * Store a destination cache entry in a socket
225 */
226static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
227 const struct in6_addr *daddr,
228 const struct in6_addr *saddr)
229{
230 struct ipv6_pinfo *np = inet6_sk(sk);
231
232 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
233 sk_setup_caps(sk, dst);
234 np->daddr_cache = daddr;
235#ifdef CONFIG_IPV6_SUBTREES
236 np->saddr_cache = saddr;
237#endif
238}
239
240void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
241 const struct flowi6 *fl6);
242
243static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
244{
245 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
246
247 return rt->rt6i_flags & RTF_LOCAL;
248}
249
250static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
251 const struct in6_addr *daddr)
252{
253 struct rt6_info *rt = (struct rt6_info *)dst;
254
255 return rt->rt6i_flags & RTF_ANYCAST ||
256 (rt->rt6i_dst.plen < 127 &&
257 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
258}
259
260int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
261 int (*output)(struct net *, struct sock *, struct sk_buff *));
262
263static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
264{
265 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
266 inet6_sk(skb->sk) : NULL;
267
268 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
269 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
270}
271
272static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
273{
274 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
275 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
276}
277
278static inline bool ip6_sk_ignore_df(const struct sock *sk)
279{
280 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
281 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
282}
283
284static inline const struct in6_addr *rt6_nexthop(const struct rt6_info *rt,
285 const struct in6_addr *daddr)
286{
287 if (rt->rt6i_flags & RTF_GATEWAY)
288 return &rt->rt6i_gateway;
289 else if (unlikely(rt->rt6i_flags & RTF_CACHE))
290 return &rt->rt6i_dst.addr;
291 else
292 return daddr;
293}
294
295static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b)
296{
297 struct fib6_nh *nha, *nhb;
298
299 if (a->nh || b->nh)
300 return nexthop_cmp(a->nh, b->nh);
301
302 nha = a->fib6_nh;
303 nhb = b->fib6_nh;
304 return nha->fib_nh_dev == nhb->fib_nh_dev &&
305 ipv6_addr_equal(&nha->fib_nh_gw6, &nhb->fib_nh_gw6) &&
306 !lwtunnel_cmp_encap(nha->fib_nh_lws, nhb->fib_nh_lws);
307}
308
309static inline unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
310{
311 struct inet6_dev *idev;
312 unsigned int mtu;
313
314 if (dst_metric_locked(dst, RTAX_MTU)) {
315 mtu = dst_metric_raw(dst, RTAX_MTU);
316 if (mtu)
317 return mtu;
318 }
319
320 mtu = IPV6_MIN_MTU;
321 rcu_read_lock();
322 idev = __in6_dev_get(dst->dev);
323 if (idev)
324 mtu = idev->cnf.mtu6;
325 rcu_read_unlock();
326
327 return mtu;
328}
329
330u32 ip6_mtu_from_fib6(const struct fib6_result *res,
331 const struct in6_addr *daddr,
332 const struct in6_addr *saddr);
333
334struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
335 struct net_device *dev, struct sk_buff *skb,
336 const void *daddr);
337#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NET_IP6_ROUTE_H
3#define _NET_IP6_ROUTE_H
4
5#include <net/addrconf.h>
6#include <net/flow.h>
7#include <net/ip6_fib.h>
8#include <net/sock.h>
9#include <net/lwtunnel.h>
10#include <linux/ip.h>
11#include <linux/ipv6.h>
12#include <linux/route.h>
13#include <net/nexthop.h>
14
15struct route_info {
16 __u8 type;
17 __u8 length;
18 __u8 prefix_len;
19#if defined(__BIG_ENDIAN_BITFIELD)
20 __u8 reserved_h:3,
21 route_pref:2,
22 reserved_l:3;
23#elif defined(__LITTLE_ENDIAN_BITFIELD)
24 __u8 reserved_l:3,
25 route_pref:2,
26 reserved_h:3;
27#endif
28 __be32 lifetime;
29 __u8 prefix[]; /* 0,8 or 16 */
30};
31
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
40
41/* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
42 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
43 */
44#define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
45
46/*
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.
53 */
54static inline int rt6_srcprefs2flags(unsigned int srcprefs)
55{
56 return (srcprefs & IPV6_PREFER_SRC_MASK) << 3;
57}
58
59static inline unsigned int rt6_flags2srcprefs(int flags)
60{
61 return (flags >> 3) & IPV6_PREFER_SRC_MASK;
62}
63
64static inline bool rt6_need_strict(const struct in6_addr *daddr)
65{
66 return ipv6_addr_type(daddr) &
67 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
68}
69
70/* fib entries using a nexthop object can not be coalesced into
71 * a multipath route
72 */
73static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i)
74{
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;
78}
79
80void ip6_route_input(struct sk_buff *skb);
81struct dst_entry *ip6_route_input_lookup(struct net *net,
82 struct net_device *dev,
83 struct flowi6 *fl6,
84 const struct sk_buff *skb, int flags);
85
86struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
87 struct flowi6 *fl6, int flags);
88
89static inline struct dst_entry *ip6_route_output(struct net *net,
90 const struct sock *sk,
91 struct flowi6 *fl6)
92{
93 return ip6_route_output_flags(net, sk, fl6, 0);
94}
95
96/* Only conditionally release dst if flags indicates
97 * !RT6_LOOKUP_F_DST_NOREF or dst is in uncached_list.
98 */
99static inline void ip6_rt_put_flags(struct rt6_info *rt, int flags)
100{
101 if (!(flags & RT6_LOOKUP_F_DST_NOREF) ||
102 !list_empty(&rt->dst.rt_uncached))
103 ip6_rt_put(rt);
104}
105
106struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
107 const struct sk_buff *skb, int flags);
108struct 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);
111
112void ip6_route_init_special_entries(void);
113int ip6_route_init(void);
114void ip6_route_cleanup(void);
115
116int ipv6_route_ioctl(struct net *net, unsigned int cmd,
117 struct in6_rtmsg *rtmsg);
118
119int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
120 struct netlink_ext_ack *extack);
121int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
122int ip6_del_rt(struct net *net, struct fib6_info *f6i, bool skip_notify);
123
124void rt6_flush_exceptions(struct fib6_info *f6i);
125void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
126 unsigned long now);
127
128static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i,
129 const struct in6_addr *daddr,
130 unsigned int prefs,
131 struct in6_addr *saddr)
132{
133 int err = 0;
134
135 if (f6i && f6i->fib6_prefsrc.plen) {
136 *saddr = f6i->fib6_prefsrc.addr;
137 } else {
138 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL;
139
140 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr);
141 }
142
143 return err;
144}
145
146struct 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);
149u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
150 const struct sk_buff *skb, struct flow_keys *hkeys);
151
152struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
153
154void fib6_force_start_gc(struct net *net);
155
156struct 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);
159
160struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
161 int flags);
162
163/*
164 * support functions for ND
165 *
166 */
167struct fib6_info *rt6_get_dflt_router(struct net *net,
168 const struct in6_addr *addr,
169 struct net_device *dev);
170struct 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);
174
175void rt6_purge_dflt_routers(struct net *net);
176
177int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
178 const struct in6_addr *gwaddr);
179
180void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
181 u32 mark, kuid_t uid);
182void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
183void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
184 kuid_t uid);
185void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif);
186void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
187
188struct netlink_callback;
189
190struct rt6_rtnl_dump_arg {
191 struct sk_buff *skb;
192 struct netlink_callback *cb;
193 struct net *net;
194 struct fib_dump_filter filter;
195};
196
197int rt6_dump_route(struct fib6_info *f6i, void *p_arg, unsigned int skip);
198void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
199void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
200void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
201void rt6_sync_up(struct net_device *dev, unsigned char nh_flags);
202void rt6_disable_ip(struct net_device *dev, unsigned long event);
203void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
204void rt6_multipath_rebalance(struct fib6_info *f6i);
205
206void rt6_uncached_list_add(struct rt6_info *rt);
207void rt6_uncached_list_del(struct rt6_info *rt);
208
209static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
210{
211 const struct dst_entry *dst = skb_dst(skb);
212 const struct rt6_info *rt6 = NULL;
213
214 if (dst)
215 rt6 = container_of(dst, struct rt6_info, dst);
216
217 return rt6;
218}
219
220/*
221 * Store a destination cache entry in a socket
222 */
223static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
224 const struct in6_addr *daddr,
225 const struct in6_addr *saddr)
226{
227 struct ipv6_pinfo *np = inet6_sk(sk);
228
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;
234#endif
235}
236
237void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
238 const struct flowi6 *fl6);
239
240static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
241{
242 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
243
244 return rt->rt6i_flags & RTF_LOCAL;
245}
246
247static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
248 const struct in6_addr *daddr)
249{
250 struct rt6_info *rt = (struct rt6_info *)dst;
251
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));
256}
257
258int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
259 int (*output)(struct net *, struct sock *, struct sk_buff *));
260
261static inline unsigned int ip6_skb_dst_mtu(const struct sk_buff *skb)
262{
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);
266 unsigned int mtu;
267
268 if (np && READ_ONCE(np->pmtudisc) >= IPV6_PMTUDISC_PROBE) {
269 mtu = READ_ONCE(dst->dev->mtu);
270 mtu -= lwtunnel_headroom(dst->lwtstate, mtu);
271 } else {
272 mtu = dst_mtu(dst);
273 }
274 return mtu;
275}
276
277static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
278{
279 u8 pmtudisc = READ_ONCE(inet6_sk(sk)->pmtudisc);
280
281 return pmtudisc != IPV6_PMTUDISC_INTERFACE &&
282 pmtudisc != IPV6_PMTUDISC_OMIT;
283}
284
285static inline bool ip6_sk_ignore_df(const struct sock *sk)
286{
287 u8 pmtudisc = READ_ONCE(inet6_sk(sk)->pmtudisc);
288
289 return pmtudisc < IPV6_PMTUDISC_DO ||
290 pmtudisc == IPV6_PMTUDISC_OMIT;
291}
292
293static inline const struct in6_addr *rt6_nexthop(const struct rt6_info *rt,
294 const struct in6_addr *daddr)
295{
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;
300 else
301 return daddr;
302}
303
304static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b)
305{
306 struct fib6_nh *nha, *nhb;
307
308 if (a->nh || b->nh)
309 return nexthop_cmp(a->nh, b->nh);
310
311 nha = a->fib6_nh;
312 nhb = b->fib6_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);
316}
317
318static inline unsigned int ip6_dst_mtu_maybe_forward(const struct dst_entry *dst,
319 bool forwarding)
320{
321 struct inet6_dev *idev;
322 unsigned int mtu;
323
324 if (!forwarding || dst_metric_locked(dst, RTAX_MTU)) {
325 mtu = dst_metric_raw(dst, RTAX_MTU);
326 if (mtu)
327 goto out;
328 }
329
330 mtu = IPV6_MIN_MTU;
331 rcu_read_lock();
332 idev = __in6_dev_get(dst->dev);
333 if (idev)
334 mtu = idev->cnf.mtu6;
335 rcu_read_unlock();
336
337out:
338 return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
339}
340
341u32 ip6_mtu_from_fib6(const struct fib6_result *res,
342 const struct in6_addr *daddr,
343 const struct in6_addr *saddr);
344
345struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
346 struct net_device *dev, struct sk_buff *skb,
347 const void *daddr);
348#endif