1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_IP6_ROUTE_H
3 #define _NET_IP6_ROUTE_H
4
5 struct 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 */
rt6_srcprefs2flags(unsigned int srcprefs)52 static 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
rt6_flags2srcprefs(int flags)58 static inline unsigned int rt6_flags2srcprefs(int flags)
59 {
60 return (flags >> 3) & 7;
61 }
62
rt6_need_strict(const struct in6_addr * daddr)63 static 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
rt6_qualify_for_ecmp(const struct fib6_info * f6i)69 static 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
75 void ip6_route_input(struct sk_buff *skb);
76 struct 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
81 struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
82 struct flowi6 *fl6, int flags);
83
ip6_route_output(struct net * net,const struct sock * sk,struct flowi6 * fl6)84 static 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
91 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
92 const struct sk_buff *skb, int flags);
93 struct 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
97 void ip6_route_init_special_entries(void);
98 int ip6_route_init(void);
99 void ip6_route_cleanup(void);
100
101 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg);
102
103 int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
104 struct netlink_ext_ack *extack);
105 int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
106 int ip6_del_rt(struct net *net, struct fib6_info *f6i);
107
108 void rt6_flush_exceptions(struct fib6_info *f6i);
109 void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
110 unsigned long now);
111
ip6_route_get_saddr(struct net * net,struct fib6_info * f6i,const struct in6_addr * daddr,unsigned int prefs,struct in6_addr * saddr)112 static 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
130 struct 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);
133 u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
134 const struct sk_buff *skb, struct flow_keys *hkeys);
135
136 struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);
137
138 void fib6_force_start_gc(struct net *net);
139
140 struct 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
144 struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
145 int flags);
146
147 /*
148 * support functions for ND
149 *
150 */
151 struct fib6_info *rt6_get_dflt_router(struct net *net,
152 const struct in6_addr *addr,
153 struct net_device *dev);
154 struct fib6_info *rt6_add_dflt_router(struct net *net,
155 const struct in6_addr *gwaddr,
156 struct net_device *dev, unsigned int pref);
157
158 void rt6_purge_dflt_routers(struct net *net);
159
160 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
161 const struct in6_addr *gwaddr);
162
163 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
164 u32 mark, kuid_t uid);
165 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
166 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
167 kuid_t uid);
168 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
169 u32 mark);
170 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);
171
172 struct netlink_callback;
173
174 struct rt6_rtnl_dump_arg {
175 struct sk_buff *skb;
176 struct netlink_callback *cb;
177 struct net *net;
178 };
179
180 int rt6_dump_route(struct fib6_info *f6i, void *p_arg);
181 void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
182 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
183 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
184 void rt6_sync_up(struct net_device *dev, unsigned int nh_flags);
185 void rt6_disable_ip(struct net_device *dev, unsigned long event);
186 void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
187 void rt6_multipath_rebalance(struct fib6_info *f6i);
188
189 void rt6_uncached_list_add(struct rt6_info *rt);
190 void rt6_uncached_list_del(struct rt6_info *rt);
191
skb_rt6_info(const struct sk_buff * skb)192 static 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 */
ip6_dst_store(struct sock * sk,struct dst_entry * dst,const struct in6_addr * daddr,const struct in6_addr * saddr)206 static 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
220 void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
221 const struct flowi6 *fl6);
222
ipv6_unicast_destination(const struct sk_buff * skb)223 static 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
ipv6_anycast_destination(const struct dst_entry * dst,const struct in6_addr * daddr)230 static 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
240 int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
241 int (*output)(struct net *, struct sock *, struct sk_buff *));
242
ip6_skb_dst_mtu(struct sk_buff * skb)243 static 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
ip6_sk_accept_pmtu(const struct sock * sk)252 static 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
ip6_sk_ignore_df(const struct sock * sk)258 static 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
rt6_nexthop(struct rt6_info * rt,struct in6_addr * daddr)264 static 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
rt6_duplicate_nexthop(struct fib6_info * a,struct fib6_info * b)275 static 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
ip6_dst_mtu_forward(const struct dst_entry * dst)282 static 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
303 u32 ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr,
304 struct in6_addr *saddr);
305
306 struct 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
