summaryrefslogtreecommitdiff
path: root/include/net/ip_tunnels.h
blob: 0b7e18cfa0b47a36b54249a715744f6855669c1e (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
#ifndef __NET_IP_TUNNELS_H
#define __NET_IP_TUNNELS_H 1

#include <linux/if_tunnel.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <linux/u64_stats_sync.h>
#include <net/dsfield.h>
#include <net/gro_cells.h>
#include <net/inet_ecn.h>
#include <net/netns/generic.h>
#include <net/rtnetlink.h>
#include <net/lwtunnel.h>

#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#endif

/* Keep error state on tunnel for 30 sec */
#define IPTUNNEL_ERR_TIMEO	(30*HZ)

/* Used to memset ip_tunnel padding. */
#define IP_TUNNEL_KEY_SIZE					\
	(offsetof(struct ip_tunnel_key, tp_dst) +		\
	 FIELD_SIZEOF(struct ip_tunnel_key, tp_dst))

struct ip_tunnel_key {
	__be64			tun_id;
	__be32			ipv4_src;
	__be32			ipv4_dst;
	__be16			tun_flags;
	__u8			ipv4_tos;
	__u8			ipv4_ttl;
	__be16			tp_src;
	__be16			tp_dst;
} __packed __aligned(4); /* Minimize padding. */

/* Indicates whether the tunnel info structure represents receive
 * or transmit tunnel parameters.
 */
enum {
	IP_TUNNEL_INFO_RX,
	IP_TUNNEL_INFO_TX,
};

struct ip_tunnel_info {
	struct ip_tunnel_key	key;
	const void		*options;
	u8			options_len;
	u8			mode;
};

/* 6rd prefix/relay information */
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd_parm {
	struct in6_addr		prefix;
	__be32			relay_prefix;
	u16			prefixlen;
	u16			relay_prefixlen;
};
#endif

struct ip_tunnel_encap {
	__u16			type;
	__u16			flags;
	__be16			sport;
	__be16			dport;
};

struct ip_tunnel_prl_entry {
	struct ip_tunnel_prl_entry __rcu *next;
	__be32				addr;
	u16				flags;
	struct rcu_head			rcu_head;
};

struct ip_tunnel_dst {
	struct dst_entry __rcu 		*dst;
	__be32				 saddr;
};

struct ip_tunnel {
	struct ip_tunnel __rcu	*next;
	struct hlist_node hash_node;
	struct net_device	*dev;
	struct net		*net;	/* netns for packet i/o */

	int		err_count;	/* Number of arrived ICMP errors */
	unsigned long	err_time;	/* Time when the last ICMP error
					 * arrived */

	/* These four fields used only by GRE */
	__u32		i_seqno;	/* The last seen seqno	*/
	__u32		o_seqno;	/* The last output seqno */
	int		tun_hlen;	/* Precalculated header length */
	int		mlink;

	struct ip_tunnel_dst __percpu *dst_cache;

	struct ip_tunnel_parm parms;

	int		encap_hlen;	/* Encap header length (FOU,GUE) */
	struct ip_tunnel_encap encap;

	int		hlen;		/* tun_hlen + encap_hlen */

	/* for SIT */
#ifdef CONFIG_IPV6_SIT_6RD
	struct ip_tunnel_6rd_parm ip6rd;
#endif
	struct ip_tunnel_prl_entry __rcu *prl;	/* potential router list */
	unsigned int		prl_count;	/* # of entries in PRL */
	int			ip_tnl_net_id;
	struct gro_cells	gro_cells;
};

#define TUNNEL_CSUM		__cpu_to_be16(0x01)
#define TUNNEL_ROUTING		__cpu_to_be16(0x02)
#define TUNNEL_KEY		__cpu_to_be16(0x04)
#define TUNNEL_SEQ		__cpu_to_be16(0x08)
#define TUNNEL_STRICT		__cpu_to_be16(0x10)
#define TUNNEL_REC		__cpu_to_be16(0x20)
#define TUNNEL_VERSION		__cpu_to_be16(0x40)
#define TUNNEL_NO_KEY		__cpu_to_be16(0x80)
#define TUNNEL_DONT_FRAGMENT    __cpu_to_be16(0x0100)
#define TUNNEL_OAM		__cpu_to_be16(0x0200)
#define TUNNEL_CRIT_OPT		__cpu_to_be16(0x0400)
#define TUNNEL_GENEVE_OPT	__cpu_to_be16(0x0800)
#define TUNNEL_VXLAN_OPT	__cpu_to_be16(0x1000)

#define TUNNEL_OPTIONS_PRESENT	(TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT)

struct tnl_ptk_info {
	__be16 flags;
	__be16 proto;
	__be32 key;
	__be32 seq;
};

#define PACKET_RCVD	0
#define PACKET_REJECT	1

#define IP_TNL_HASH_BITS   7
#define IP_TNL_HASH_SIZE   (1 << IP_TNL_HASH_BITS)

struct ip_tunnel_net {
	struct net_device *fb_tunnel_dev;
	struct hlist_head tunnels[IP_TNL_HASH_SIZE];
};

struct ip_tunnel_encap_ops {
	size_t (*encap_hlen)(struct ip_tunnel_encap *e);
	int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
			    u8 *protocol, struct flowi4 *fl4);
};

#define MAX_IPTUN_ENCAP_OPS 8

extern const struct ip_tunnel_encap_ops __rcu *
		iptun_encaps[MAX_IPTUN_ENCAP_OPS];

int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
			    unsigned int num);
int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
			    unsigned int num);

static inline void __ip_tunnel_info_init(struct ip_tunnel_info *tun_info,
					 __be32 saddr, __be32 daddr,
					 u8 tos, u8 ttl,
					 __be16 tp_src, __be16 tp_dst,
					 __be64 tun_id, __be16 tun_flags,
					 const void *opts, u8 opts_len)
{
	tun_info->key.tun_id = tun_id;
	tun_info->key.ipv4_src = saddr;
	tun_info->key.ipv4_dst = daddr;
	tun_info->key.ipv4_tos = tos;
	tun_info->key.ipv4_ttl = ttl;
	tun_info->key.tun_flags = tun_flags;

	/* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
	 * the upper tunnel are used.
	 * E.g: GRE over IPSEC, the tp_src and tp_port are zero.
	 */
	tun_info->key.tp_src = tp_src;
	tun_info->key.tp_dst = tp_dst;

	/* Clear struct padding. */
	if (sizeof(tun_info->key) != IP_TUNNEL_KEY_SIZE)
		memset((unsigned char *)&tun_info->key + IP_TUNNEL_KEY_SIZE,
		       0, sizeof(tun_info->key) - IP_TUNNEL_KEY_SIZE);

	tun_info->options = opts;
	tun_info->options_len = opts_len;
}

static inline void ip_tunnel_info_init(struct ip_tunnel_info *tun_info,
				       const struct iphdr *iph,
				       __be16 tp_src, __be16 tp_dst,
				       __be64 tun_id, __be16 tun_flags,
				       const void *opts, u8 opts_len)
{
	__ip_tunnel_info_init(tun_info, iph->saddr, iph->daddr,
			      iph->tos, iph->ttl, tp_src, tp_dst,
			      tun_id, tun_flags, opts, opts_len);
}

#ifdef CONFIG_INET

int ip_tunnel_init(struct net_device *dev);
void ip_tunnel_uninit(struct net_device *dev);
void  ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
struct net *ip_tunnel_get_link_net(const struct net_device *dev);
int ip_tunnel_get_iflink(const struct net_device *dev);
int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
		       struct rtnl_link_ops *ops, char *devname);

void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);

void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
		    const struct iphdr *tnl_params, const u8 protocol);
int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
		    u8 *protocol, struct flowi4 *fl4);
int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);

struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
						struct rtnl_link_stats64 *tot);
struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
				   int link, __be16 flags,
				   __be32 remote, __be32 local,
				   __be32 key);

int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
		  const struct tnl_ptk_info *tpi, bool log_ecn_error);
int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
			 struct ip_tunnel_parm *p);
int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
		      struct ip_tunnel_parm *p);
void ip_tunnel_setup(struct net_device *dev, int net_id);
void ip_tunnel_dst_reset_all(struct ip_tunnel *t);
int ip_tunnel_encap_setup(struct ip_tunnel *t,
			  struct ip_tunnel_encap *ipencap);

/* Extract dsfield from inner protocol */
static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
				       const struct sk_buff *skb)
{
	if (skb->protocol == htons(ETH_P_IP))
		return iph->tos;
	else if (skb->protocol == htons(ETH_P_IPV6))
		return ipv6_get_dsfield((const struct ipv6hdr *)iph);
	else
		return 0;
}

/* Propogate ECN bits out */
static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
				     const struct sk_buff *skb)
{
	u8 inner = ip_tunnel_get_dsfield(iph, skb);

	return INET_ECN_encapsulate(tos, inner);
}

int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto);
int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
		  __be32 src, __be32 dst, __u8 proto,
		  __u8 tos, __u8 ttl, __be16 df, bool xnet);

struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, bool gre_csum,
					 int gso_type_mask);

static inline void iptunnel_xmit_stats(int err,
				       struct net_device_stats *err_stats,
				       struct pcpu_sw_netstats __percpu *stats)
{
	if (err > 0) {
		struct pcpu_sw_netstats *tstats = this_cpu_ptr(stats);

		u64_stats_update_begin(&tstats->syncp);
		tstats->tx_bytes += err;
		tstats->tx_packets++;
		u64_stats_update_end(&tstats->syncp);
	} else if (err < 0) {
		err_stats->tx_errors++;
		err_stats->tx_aborted_errors++;
	} else {
		err_stats->tx_dropped++;
	}
}

static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info, size_t n)
{
	return info + 1;
}

static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
{
	return (struct ip_tunnel_info *)lwtstate->data;
}

#endif /* CONFIG_INET */

#endif /* __NET_IP_TUNNELS_H */