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
31#define RT6_LOOKUP_F_IFACE 0x00000001
32#define RT6_LOOKUP_F_REACHABLE 0x00000002
33#define RT6_LOOKUP_F_HAS_SADDR 0x00000004
34#define RT6_LOOKUP_F_SRCPREF_TMP 0x00000008
35#define RT6_LOOKUP_F_SRCPREF_PUBLIC 0x00000010
36#define RT6_LOOKUP_F_SRCPREF_COA 0x00000020
37#define RT6_LOOKUP_F_IGNORE_LINKSTATE 0x00000040
38
39/* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
40 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
41 */
42#define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))
43
44/*
45 * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
46 * between IPV6_ADDR_PREFERENCES socket option values
47 * IPV6_PREFER_SRC_TMP = 0x1
48 * IPV6_PREFER_SRC_PUBLIC = 0x2
49 * IPV6_PREFER_SRC_COA = 0x4
50 * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
51 */
52static inline int rt6_srcprefs2flags(unsigned int srcprefs)
53{
54 /* No need to bitmask because srcprefs have only 3 bits. */
55 return srcprefs << 3;
56}
57
58static inline unsigned int rt6_flags2srcprefs(int flags)
59{
60 return (flags >> 3) & 7;
61}
62
63static inline bool rt6_need_strict(const struct in6_addr *daddr)
64{
65 return ipv6_addr_type(daddr) &
66 (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
67}
68
69static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i)
70{
71 return (f6i->fib6_flags & (RTF_GATEWAY|RTF_ADDRCONF|RTF_DYNAMIC)) ==
72 RTF_GATEWAY;
73}
74
75void ip6_route_input(struct sk_buff *skb);
76struct dst_entry *ip6_route_input_lookup(struct net *net,
77 struct net_device *dev,
78 struct flowi6 *fl6,
79 const struct sk_buff *skb, int flags);
80
81struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
82 struct flowi6 *fl6, int flags);
83
84static inline struct dst_entry *ip6_route_output(struct net *net,
85 const struct sock *sk,
86 struct flowi6 *fl6)
87{
88 return ip6_route_output_flags(net, sk, fl6, 0);
89}
90
91struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
92 const struct sk_buff *skb, int flags);
93struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
94 int ifindex, struct flowi6 *fl6,
95 const struct sk_buff *skb, int flags);
96
97void ip6_route_init_special_entries(void);
98int ip6_route_init(void);
99void ip6_route_cleanup(void);
100
101int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
102
103int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
104 struct netlink_ext_ack *extack);
105int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
106int ip6_del_rt(struct net *net, struct fib6_info *f6i);
107
108void rt6_flush_exceptions(struct fib6_info *f6i);
109void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
110 unsigned long now);
111
112static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i,
113 const struct in6_addr *daddr,
114 unsigned int prefs,
115 struct in6_addr *saddr)
116{
117 int err = 0;
118
119 if (f6i && f6i->fib6_prefsrc.plen) {
120 *saddr = f6i->fib6_prefsrc.addr;
121 } else {
122 struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL;
123
124 err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr);
125 }
126
127 return err;
128}
129
130struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
131 const struct in6_addr *saddr, int oif,
132 const struct sk_buff *skb, int flags);
133u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
134 const struct sk_buff *skb, struct flow_keys *hkeys);
135
136struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
137
138void fib6_force_start_gc(struct net *net);
139
140struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev,
141 const struct in6_addr *addr, bool anycast,
142 gfp_t gfp_flags);
143
144struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
145 int flags);
146
147/*
148 * support functions for ND
149 *
150 */
151struct fib6_info *rt6_get_dflt_router(struct net *net,
152 const struct in6_addr *addr,
153 struct net_device *dev);
154struct fib6_info *rt6_add_dflt_router(struct net *net,
155 const struct in6_addr *gwaddr,
156 struct net_device *dev, unsigned int pref);
157
158void rt6_purge_dflt_routers(struct net *net);
159
160int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
161 const struct in6_addr *gwaddr);
162
163void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
164 u32 mark, kuid_t uid);
165void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
166void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
167 kuid_t uid);
168void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif);
169void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
170
171struct netlink_callback;
172
173struct rt6_rtnl_dump_arg {
174 struct sk_buff *skb;
175 struct netlink_callback *cb;
176 struct net *net;
177 struct fib_dump_filter filter;
178};
179
180int rt6_dump_route(struct fib6_info *f6i, void *p_arg);
181void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
182void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
183void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
184void rt6_sync_up(struct net_device *dev, unsigned int nh_flags);
185void rt6_disable_ip(struct net_device *dev, unsigned long event);
186void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
187void rt6_multipath_rebalance(struct fib6_info *f6i);
188
189void rt6_uncached_list_add(struct rt6_info *rt);
190void rt6_uncached_list_del(struct rt6_info *rt);
191
192static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
193{
194 const struct dst_entry *dst = skb_dst(skb);
195 const struct rt6_info *rt6 = NULL;
196
197 if (dst)
198 rt6 = container_of(dst, struct rt6_info, dst);
199
200 return rt6;
201}
202
203/*
204 * Store a destination cache entry in a socket
205 */
206static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
207 const struct in6_addr *daddr,
208 const struct in6_addr *saddr)
209{
210 struct ipv6_pinfo *np = inet6_sk(sk);
211
212 np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
213 sk_setup_caps(sk, dst);
214 np->daddr_cache = daddr;
215#ifdef CONFIG_IPV6_SUBTREES
216 np->saddr_cache = saddr;
217#endif
218}
219
220void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
221 const struct flowi6 *fl6);
222
223static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
224{
225 struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);
226
227 return rt->rt6i_flags & RTF_LOCAL;
228}
229
230static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
231 const struct in6_addr *daddr)
232{
233 struct rt6_info *rt = (struct rt6_info *)dst;
234
235 return rt->rt6i_flags & RTF_ANYCAST ||
236 (rt->rt6i_dst.plen < 127 &&
237 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
238}
239
240int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
241 int (*output)(struct net *, struct sock *, struct sk_buff *));
242
243static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
244{
245 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
246 inet6_sk(skb->sk) : NULL;
247
248 return (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) ?
249 skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
250}
251
252static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
253{
254 return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
255 inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
256}
257
258static inline bool ip6_sk_ignore_df(const struct sock *sk)
259{
260 return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
261 inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
262}
263
264static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt,
265 struct in6_addr *daddr)
266{
267 if (rt->rt6i_flags & RTF_GATEWAY)
268 return &rt->rt6i_gateway;
269 else if (unlikely(rt->rt6i_flags & RTF_CACHE))
270 return &rt->rt6i_dst.addr;
271 else
272 return daddr;
273}
274
275static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b)
276{
277 return a->fib6_nh.nh_dev == b->fib6_nh.nh_dev &&
278 ipv6_addr_equal(&a->fib6_nh.nh_gw, &b->fib6_nh.nh_gw) &&
279 !lwtunnel_cmp_encap(a->fib6_nh.nh_lwtstate, b->fib6_nh.nh_lwtstate);
280}
281
282static inline unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
283{
284 struct inet6_dev *idev;
285 unsigned int mtu;
286
287 if (dst_metric_locked(dst, RTAX_MTU)) {
288 mtu = dst_metric_raw(dst, RTAX_MTU);
289 if (mtu)
290 return mtu;
291 }
292
293 mtu = IPV6_MIN_MTU;
294 rcu_read_lock();
295 idev = __in6_dev_get(dst->dev);
296 if (idev)
297 mtu = idev->cnf.mtu6;
298 rcu_read_unlock();
299
300 return mtu;
301}
302
303u32 ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr,
304 struct in6_addr *saddr);
305
306struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
307 struct net_device *dev, struct sk_buff *skb,
308 const void *daddr);
309#endif
310