summaryrefslogtreecommitdiff
path: root/include/net/ip6_route.h
blob: 0bf09a9bca4e02db4c8b722a4b69591cd93e598c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NET_IP6_ROUTE_H
#define _NET_IP6_ROUTE_H

struct route_info {
	__u8			type;
	__u8			length;
	__u8			prefix_len;
#if defined(__BIG_ENDIAN_BITFIELD)
	__u8			reserved_h:3,
				route_pref:2,
				reserved_l:3;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
	__u8			reserved_l:3,
				route_pref:2,
				reserved_h:3;
#endif
	__be32			lifetime;
	__u8			prefix[];	/* 0,8 or 16 */
};

#include <net/addrconf.h>
#include <net/flow.h>
#include <net/ip6_fib.h>
#include <net/sock.h>
#include <net/lwtunnel.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/route.h>
#include <net/nexthop.h>

#define RT6_LOOKUP_F_IFACE		0x00000001
#define RT6_LOOKUP_F_REACHABLE		0x00000002
#define RT6_LOOKUP_F_HAS_SADDR		0x00000004
#define RT6_LOOKUP_F_SRCPREF_TMP	0x00000008
#define RT6_LOOKUP_F_SRCPREF_PUBLIC	0x00000010
#define RT6_LOOKUP_F_SRCPREF_COA	0x00000020
#define RT6_LOOKUP_F_IGNORE_LINKSTATE	0x00000040
#define RT6_LOOKUP_F_DST_NOREF		0x00000080

/* We do not (yet ?) support IPv6 jumbograms (RFC 2675)
 * Unlike IPv4, hdr->seg_len doesn't include the IPv6 header
 */
#define IP6_MAX_MTU (0xFFFF + sizeof(struct ipv6hdr))

/*
 * rt6_srcprefs2flags() and rt6_flags2srcprefs() translate
 * between IPV6_ADDR_PREFERENCES socket option values
 *	IPV6_PREFER_SRC_TMP    = 0x1
 *	IPV6_PREFER_SRC_PUBLIC = 0x2
 *	IPV6_PREFER_SRC_COA    = 0x4
 * and above RT6_LOOKUP_F_SRCPREF_xxx flags.
 */
static inline int rt6_srcprefs2flags(unsigned int srcprefs)
{
	/* No need to bitmask because srcprefs have only 3 bits. */
	return srcprefs << 3;
}

static inline unsigned int rt6_flags2srcprefs(int flags)
{
	return (flags >> 3) & 7;
}

static inline bool rt6_need_strict(const struct in6_addr *daddr)
{
	return ipv6_addr_type(daddr) &
		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
}

/* fib entries using a nexthop object can not be coalesced into
 * a multipath route
 */
static inline bool rt6_qualify_for_ecmp(const struct fib6_info *f6i)
{
	/* the RTF_ADDRCONF flag filters out RA's */
	return !(f6i->fib6_flags & RTF_ADDRCONF) && !f6i->nh &&
		f6i->fib6_nh->fib_nh_gw_family;
}

void ip6_route_input(struct sk_buff *skb);
struct dst_entry *ip6_route_input_lookup(struct net *net,
					 struct net_device *dev,
					 struct flowi6 *fl6,
					 const struct sk_buff *skb, int flags);

struct dst_entry *ip6_route_output_flags_noref(struct net *net,
					       const struct sock *sk,
					       struct flowi6 *fl6, int flags);

struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
					 struct flowi6 *fl6, int flags);

static inline struct dst_entry *ip6_route_output(struct net *net,
						 const struct sock *sk,
						 struct flowi6 *fl6)
{
	return ip6_route_output_flags(net, sk, fl6, 0);
}

/* Only conditionally release dst if flags indicates
 * !RT6_LOOKUP_F_DST_NOREF or dst is in uncached_list.
 */
static inline void ip6_rt_put_flags(struct rt6_info *rt, int flags)
{
	if (!(flags & RT6_LOOKUP_F_DST_NOREF) ||
	    !list_empty(&rt->rt6i_uncached))
		ip6_rt_put(rt);
}

struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
				   const struct sk_buff *skb, int flags);
struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
			       int ifindex, struct flowi6 *fl6,
			       const struct sk_buff *skb, int flags);

void ip6_route_init_special_entries(void);
int ip6_route_init(void);
void ip6_route_cleanup(void);

int ipv6_route_ioctl(struct net *net, unsigned int cmd,
		struct in6_rtmsg *rtmsg);

int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
		  struct netlink_ext_ack *extack);
int ip6_ins_rt(struct net *net, struct fib6_info *f6i);
int ip6_del_rt(struct net *net, struct fib6_info *f6i, bool skip_notify);

void rt6_flush_exceptions(struct fib6_info *f6i);
void rt6_age_exceptions(struct fib6_info *f6i, struct fib6_gc_args *gc_args,
			unsigned long now);

static inline int ip6_route_get_saddr(struct net *net, struct fib6_info *f6i,
				      const struct in6_addr *daddr,
				      unsigned int prefs,
				      struct in6_addr *saddr)
{
	int err = 0;

	if (f6i && f6i->fib6_prefsrc.plen) {
		*saddr = f6i->fib6_prefsrc.addr;
	} else {
		struct net_device *dev = f6i ? fib6_info_nh_dev(f6i) : NULL;

		err = ipv6_dev_get_saddr(net, dev, daddr, prefs, saddr);
	}

	return err;
}

struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
			    const struct in6_addr *saddr, int oif,
			    const struct sk_buff *skb, int flags);
u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6,
		       const struct sk_buff *skb, struct flow_keys *hkeys);

struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6);

void fib6_force_start_gc(struct net *net);

struct fib6_info *addrconf_f6i_alloc(struct net *net, struct inet6_dev *idev,
				     const struct in6_addr *addr, bool anycast,
				     gfp_t gfp_flags);

struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev,
			       int flags);

/*
 *	support functions for ND
 *
 */
struct fib6_info *rt6_get_dflt_router(struct net *net,
				     const struct in6_addr *addr,
				     struct net_device *dev);
struct fib6_info *rt6_add_dflt_router(struct net *net,
				     const struct in6_addr *gwaddr,
				     struct net_device *dev, unsigned int pref,
				     u32 defrtr_usr_metric);

void rt6_purge_dflt_routers(struct net *net);

int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
		  const struct in6_addr *gwaddr);

void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, int oif,
		     u32 mark, kuid_t uid);
void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu);
void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
		  kuid_t uid);
void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif);
void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk);

struct netlink_callback;

struct rt6_rtnl_dump_arg {
	struct sk_buff *skb;
	struct netlink_callback *cb;
	struct net *net;
	struct fib_dump_filter filter;
};

int rt6_dump_route(struct fib6_info *f6i, void *p_arg, unsigned int skip);
void rt6_mtu_change(struct net_device *dev, unsigned int mtu);
void rt6_remove_prefsrc(struct inet6_ifaddr *ifp);
void rt6_clean_tohost(struct net *net, struct in6_addr *gateway);
void rt6_sync_up(struct net_device *dev, unsigned char nh_flags);
void rt6_disable_ip(struct net_device *dev, unsigned long event);
void rt6_sync_down_dev(struct net_device *dev, unsigned long event);
void rt6_multipath_rebalance(struct fib6_info *f6i);

void rt6_uncached_list_add(struct rt6_info *rt);
void rt6_uncached_list_del(struct rt6_info *rt);

static inline const struct rt6_info *skb_rt6_info(const struct sk_buff *skb)
{
	const struct dst_entry *dst = skb_dst(skb);
	const struct rt6_info *rt6 = NULL;

	if (dst)
		rt6 = container_of(dst, struct rt6_info, dst);

	return rt6;
}

/*
 *	Store a destination cache entry in a socket
 */
static inline void ip6_dst_store(struct sock *sk, struct dst_entry *dst,
				 const struct in6_addr *daddr,
				 const struct in6_addr *saddr)
{
	struct ipv6_pinfo *np = inet6_sk(sk);

	np->dst_cookie = rt6_get_cookie((struct rt6_info *)dst);
	sk_setup_caps(sk, dst);
	np->daddr_cache = daddr;
#ifdef CONFIG_IPV6_SUBTREES
	np->saddr_cache = saddr;
#endif
}

void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
			   const struct flowi6 *fl6);

static inline bool ipv6_unicast_destination(const struct sk_buff *skb)
{
	struct rt6_info *rt = (struct rt6_info *) skb_dst(skb);

	return rt->rt6i_flags & RTF_LOCAL;
}

static inline bool ipv6_anycast_destination(const struct dst_entry *dst,
					    const struct in6_addr *daddr)
{
	struct rt6_info *rt = (struct rt6_info *)dst;

	return rt->rt6i_flags & RTF_ANYCAST ||
		(rt->rt6i_dst.plen < 127 &&
		 !(rt->rt6i_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) &&
		 ipv6_addr_equal(&rt->rt6i_dst.addr, daddr));
}

int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
		 int (*output)(struct net *, struct sock *, struct sk_buff *));

static inline unsigned int ip6_skb_dst_mtu(struct sk_buff *skb)
{
	unsigned int mtu;

	struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
				inet6_sk(skb->sk) : NULL;

	if (np && np->pmtudisc >= IPV6_PMTUDISC_PROBE) {
		mtu = READ_ONCE(skb_dst(skb)->dev->mtu);
		mtu -= lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu);
	} else
		mtu = dst_mtu(skb_dst(skb));

	return mtu;
}

static inline bool ip6_sk_accept_pmtu(const struct sock *sk)
{
	return inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_INTERFACE &&
	       inet6_sk(sk)->pmtudisc != IPV6_PMTUDISC_OMIT;
}

static inline bool ip6_sk_ignore_df(const struct sock *sk)
{
	return inet6_sk(sk)->pmtudisc < IPV6_PMTUDISC_DO ||
	       inet6_sk(sk)->pmtudisc == IPV6_PMTUDISC_OMIT;
}

static inline const struct in6_addr *rt6_nexthop(const struct rt6_info *rt,
						 const struct in6_addr *daddr)
{
	if (rt->rt6i_flags & RTF_GATEWAY)
		return &rt->rt6i_gateway;
	else if (unlikely(rt->rt6i_flags & RTF_CACHE))
		return &rt->rt6i_dst.addr;
	else
		return daddr;
}

static inline bool rt6_duplicate_nexthop(struct fib6_info *a, struct fib6_info *b)
{
	struct fib6_nh *nha, *nhb;

	if (a->nh || b->nh)
		return nexthop_cmp(a->nh, b->nh);

	nha = a->fib6_nh;
	nhb = b->fib6_nh;
	return nha->fib_nh_dev == nhb->fib_nh_dev &&
	       ipv6_addr_equal(&nha->fib_nh_gw6, &nhb->fib_nh_gw6) &&
	       !lwtunnel_cmp_encap(nha->fib_nh_lws, nhb->fib_nh_lws);
}

static inline unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
{
	struct inet6_dev *idev;
	unsigned int mtu;

	if (dst_metric_locked(dst, RTAX_MTU)) {
		mtu = dst_metric_raw(dst, RTAX_MTU);
		if (mtu)
			goto out;
	}

	mtu = IPV6_MIN_MTU;
	rcu_read_lock();
	idev = __in6_dev_get(dst->dev);
	if (idev)
		mtu = idev->cnf.mtu6;
	rcu_read_unlock();

out:
	return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
}

u32 ip6_mtu_from_fib6(const struct fib6_result *res,
		      const struct in6_addr *daddr,
		      const struct in6_addr *saddr);

struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
				   struct net_device *dev, struct sk_buff *skb,
				   const void *daddr);
#endif