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 | |
15 | struct 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 | */ |
54 | static inline int rt6_srcprefs2flags(unsigned int srcprefs) |
55 | { |
56 | return (srcprefs & IPV6_PREFER_SRC_MASK) << 3; |
57 | } |
58 | |
59 | static inline unsigned int rt6_flags2srcprefs(int flags) |
60 | { |
61 | return (flags >> 3) & IPV6_PREFER_SRC_MASK; |
62 | } |
63 | |
64 | static inline bool rt6_need_strict(const struct in6_addr *daddr) |
65 | { |
66 | return ipv6_addr_type(addr: 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 | */ |
73 | static 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 | |
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, |
83 | struct flowi6 *fl6, |
84 | const struct sk_buff *skb, int flags); |
85 | |
86 | struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, |
87 | struct flowi6 *fl6, int flags); |
88 | |
89 | static 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, flags: 0); |
94 | } |
95 | |
96 | /* Only conditionally release dst if flags indicates |
97 | * !RT6_LOOKUP_F_DST_NOREF or dst is in uncached_list. |
98 | */ |
99 | static inline void ip6_rt_put_flags(struct rt6_info *rt, int flags) |
100 | { |
101 | if (!(flags & RT6_LOOKUP_F_DST_NOREF) || |
102 | !list_empty(head: &rt->dst.rt_uncached)) |
103 | ip6_rt_put(rt); |
104 | } |
105 | |
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); |
111 | |
112 | void ip6_route_init_special_entries(void); |
113 | int ip6_route_init(void); |
114 | void ip6_route_cleanup(void); |
115 | |
116 | int ipv6_route_ioctl(struct net *net, unsigned int cmd, |
117 | struct in6_rtmsg *rtmsg); |
118 | |
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); |
123 | |
124 | void rt6_flush_exceptions(struct fib6_info *f6i); |
125 | void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args, |
126 | unsigned long now); |
127 | |
128 | static 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, srcprefs: prefs, saddr); |
141 | } |
142 | |
143 | return err; |
144 | } |
145 | |
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); |
151 | |
152 | struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6); |
153 | |
154 | void fib6_force_start_gc(struct net *net); |
155 | |
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); |
159 | |
160 | struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, |
161 | int flags); |
162 | |
163 | /* |
164 | * support functions for ND |
165 | * |
166 | */ |
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); |
174 | |
175 | void rt6_purge_dflt_routers(struct net *net); |
176 | |
177 | int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, |
178 | const struct in6_addr *gwaddr); |
179 | |
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, |
184 | kuid_t uid); |
185 | void (struct sk_buff *skb, struct net *net, int oif); |
186 | void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk); |
187 | |
188 | struct netlink_callback; |
189 | |
190 | struct 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 | |
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); |
205 | |
206 | void rt6_uncached_list_add(struct rt6_info *rt); |
207 | void rt6_uncached_list_del(struct rt6_info *rt); |
208 | |
209 | static 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 | */ |
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) |
226 | { |
227 | struct ipv6_pinfo *np = inet6_sk(sk: sk); |
228 | |
229 | np->dst_cookie = rt6_get_cookie(rt: (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 | |
237 | void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, |
238 | const struct flowi6 *fl6); |
239 | |
240 | static 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 | |
247 | static 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(a1: &rt->rt6i_dst.addr, a2: daddr)); |
256 | } |
257 | |
258 | int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, |
259 | int (*output)(struct net *, struct sock *, struct sk_buff *)); |
260 | |
261 | static 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(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(lwtstate: dst->lwtstate, mtu); |
271 | } else { |
272 | mtu = dst_mtu(dst); |
273 | } |
274 | return mtu; |
275 | } |
276 | |
277 | static 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 | |
285 | static 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 | |
293 | static 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 | |
304 | static 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(nh1: a->nh, nh2: 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(a1: &nha->fib_nh_gw6, a2: &nhb->fib_nh_gw6) && |
315 | !lwtunnel_cmp_encap(a: nha->fib_nh_lws, b: nhb->fib_nh_lws); |
316 | } |
317 | |
318 | static 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(dev: dst->dev); |
333 | if (idev) |
334 | mtu = idev->cnf.mtu6; |
335 | rcu_read_unlock(); |
336 | |
337 | out: |
338 | return mtu - lwtunnel_headroom(lwtstate: dst->lwtstate, mtu); |
339 | } |
340 | |
341 | u32 ip6_mtu_from_fib6(const struct fib6_result *res, |
342 | const struct in6_addr *daddr, |
343 | const struct in6_addr *saddr); |
344 | |
345 | struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw, |
346 | struct net_device *dev, struct sk_buff *skb, |
347 | const void *daddr); |
348 | #endif |
349 | |