1 #ifndef __NET_IP_TUNNELS_H
2 #define __NET_IP_TUNNELS_H 1
3
4 #include <linux/if_tunnel.h>
5 #include <linux/netdevice.h>
6 #include <linux/skbuff.h>
7 #include <linux/socket.h>
8 #include <linux/types.h>
9 #include <linux/u64_stats_sync.h>
10 #include <linux/bitops.h>
11
12 #include <net/dsfield.h>
13 #include <net/gro_cells.h>
14 #include <net/inet_ecn.h>
15 #include <net/netns/generic.h>
16 #include <net/rtnetlink.h>
17 #include <net/lwtunnel.h>
18 #include <net/dst_cache.h>
19
20 #if IS_ENABLED(CONFIG_IPV6)
21 #include <net/ipv6.h>
22 #include <net/ip6_fib.h>
23 #include <net/ip6_route.h>
24 #endif
25
26 /* Keep error state on tunnel for 30 sec */
27 #define IPTUNNEL_ERR_TIMEO (30*HZ)
28
29 /* Used to memset ip_tunnel padding. */
30 #define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst)
31
32 /* Used to memset ipv4 address padding. */
33 #define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst)
34 #define IP_TUNNEL_KEY_IPV4_PAD_LEN \
35 (FIELD_SIZEOF(struct ip_tunnel_key, u) - \
36 FIELD_SIZEOF(struct ip_tunnel_key, u.ipv4))
37
38 struct ip_tunnel_key {
39 __be64 tun_id;
40 union {
41 struct {
42 __be32 src;
43 __be32 dst;
44 } ipv4;
45 struct {
46 struct in6_addr src;
47 struct in6_addr dst;
48 } ipv6;
49 } u;
50 __be16 tun_flags;
51 u8 tos; /* TOS for IPv4, TC for IPv6 */
52 u8 ttl; /* TTL for IPv4, HL for IPv6 */
53 __be32 label; /* Flow Label for IPv6 */
54 __be16 tp_src;
55 __be16 tp_dst;
56 };
57
58 /* Flags for ip_tunnel_info mode. */
59 #define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */
60 #define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */
61
62 /* Maximum tunnel options length. */
63 #define IP_TUNNEL_OPTS_MAX \
64 GENMASK((FIELD_SIZEOF(struct ip_tunnel_info, \
65 options_len) * BITS_PER_BYTE) - 1, 0)
66
67 struct ip_tunnel_info {
68 struct ip_tunnel_key key;
69 #ifdef CONFIG_DST_CACHE
70 struct dst_cache dst_cache;
71 #endif
72 u8 options_len;
73 u8 mode;
74 };
75
76 /* 6rd prefix/relay information */
77 #ifdef CONFIG_IPV6_SIT_6RD
78 struct ip_tunnel_6rd_parm {
79 struct in6_addr prefix;
80 __be32 relay_prefix;
81 u16 prefixlen;
82 u16 relay_prefixlen;
83 };
84 #endif
85
86 struct ip_tunnel_encap {
87 u16 type;
88 u16 flags;
89 __be16 sport;
90 __be16 dport;
91 };
92
93 struct ip_tunnel_prl_entry {
94 struct ip_tunnel_prl_entry __rcu *next;
95 __be32 addr;
96 u16 flags;
97 struct rcu_head rcu_head;
98 };
99
100 struct metadata_dst;
101
102 struct ip_tunnel {
103 struct ip_tunnel __rcu *next;
104 struct hlist_node hash_node;
105 struct net_device *dev;
106 struct net *net; /* netns for packet i/o */
107
108 unsigned long err_time; /* Time when the last ICMP error
109 * arrived */
110 int err_count; /* Number of arrived ICMP errors */
111
112 /* These four fields used only by GRE */
113 u32 i_seqno; /* The last seen seqno */
114 u32 o_seqno; /* The last output seqno */
115 int tun_hlen; /* Precalculated header length */
116
117 struct dst_cache dst_cache;
118
119 struct ip_tunnel_parm parms;
120
121 int mlink;
122 int encap_hlen; /* Encap header length (FOU,GUE) */
123 int hlen; /* tun_hlen + encap_hlen */
124 struct ip_tunnel_encap encap;
125
126 /* for SIT */
127 #ifdef CONFIG_IPV6_SIT_6RD
128 struct ip_tunnel_6rd_parm ip6rd;
129 #endif
130 struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */
131 unsigned int prl_count; /* # of entries in PRL */
132 int ip_tnl_net_id;
133 struct gro_cells gro_cells;
134 bool collect_md;
135 bool ignore_df;
136 };
137
138 #define TUNNEL_CSUM __cpu_to_be16(0x01)
139 #define TUNNEL_ROUTING __cpu_to_be16(0x02)
140 #define TUNNEL_KEY __cpu_to_be16(0x04)
141 #define TUNNEL_SEQ __cpu_to_be16(0x08)
142 #define TUNNEL_STRICT __cpu_to_be16(0x10)
143 #define TUNNEL_REC __cpu_to_be16(0x20)
144 #define TUNNEL_VERSION __cpu_to_be16(0x40)
145 #define TUNNEL_NO_KEY __cpu_to_be16(0x80)
146 #define TUNNEL_DONT_FRAGMENT __cpu_to_be16(0x0100)
147 #define TUNNEL_OAM __cpu_to_be16(0x0200)
148 #define TUNNEL_CRIT_OPT __cpu_to_be16(0x0400)
149 #define TUNNEL_GENEVE_OPT __cpu_to_be16(0x0800)
150 #define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000)
151 #define TUNNEL_NOCACHE __cpu_to_be16(0x2000)
152
153 #define TUNNEL_OPTIONS_PRESENT (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT)
154
155 struct tnl_ptk_info {
156 __be16 flags;
157 __be16 proto;
158 __be32 key;
159 __be32 seq;
160 int hdr_len;
161 };
162
163 #define PACKET_RCVD 0
164 #define PACKET_REJECT 1
165 #define PACKET_NEXT 2
166
167 #define IP_TNL_HASH_BITS 7
168 #define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS)
169
170 struct ip_tunnel_net {
171 struct net_device *fb_tunnel_dev;
172 struct hlist_head tunnels[IP_TNL_HASH_SIZE];
173 struct ip_tunnel __rcu *collect_md_tun;
174 };
175
ip_tunnel_key_init(struct ip_tunnel_key * key,__be32 saddr,__be32 daddr,u8 tos,u8 ttl,__be32 label,__be16 tp_src,__be16 tp_dst,__be64 tun_id,__be16 tun_flags)176 static inline void ip_tunnel_key_init(struct ip_tunnel_key *key,
177 __be32 saddr, __be32 daddr,
178 u8 tos, u8 ttl, __be32 label,
179 __be16 tp_src, __be16 tp_dst,
180 __be64 tun_id, __be16 tun_flags)
181 {
182 key->tun_id = tun_id;
183 key->u.ipv4.src = saddr;
184 key->u.ipv4.dst = daddr;
185 memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD,
186 0, IP_TUNNEL_KEY_IPV4_PAD_LEN);
187 key->tos = tos;
188 key->ttl = ttl;
189 key->label = label;
190 key->tun_flags = tun_flags;
191
192 /* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
193 * the upper tunnel are used.
194 * E.g: GRE over IPSEC, the tp_src and tp_port are zero.
195 */
196 key->tp_src = tp_src;
197 key->tp_dst = tp_dst;
198
199 /* Clear struct padding. */
200 if (sizeof(*key) != IP_TUNNEL_KEY_SIZE)
201 memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE,
202 0, sizeof(*key) - IP_TUNNEL_KEY_SIZE);
203 }
204
205 static inline bool
ip_tunnel_dst_cache_usable(const struct sk_buff * skb,const struct ip_tunnel_info * info)206 ip_tunnel_dst_cache_usable(const struct sk_buff *skb,
207 const struct ip_tunnel_info *info)
208 {
209 if (skb->mark)
210 return false;
211 if (!info)
212 return true;
213 if (info->key.tun_flags & TUNNEL_NOCACHE)
214 return false;
215
216 return true;
217 }
218
ip_tunnel_info_af(const struct ip_tunnel_info * tun_info)219 static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info
220 *tun_info)
221 {
222 return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET;
223 }
224
key32_to_tunnel_id(__be32 key)225 static inline __be64 key32_to_tunnel_id(__be32 key)
226 {
227 #ifdef __BIG_ENDIAN
228 return (__force __be64)key;
229 #else
230 return (__force __be64)((__force u64)key << 32);
231 #endif
232 }
233
234 /* Returns the least-significant 32 bits of a __be64. */
tunnel_id_to_key32(__be64 tun_id)235 static inline __be32 tunnel_id_to_key32(__be64 tun_id)
236 {
237 #ifdef __BIG_ENDIAN
238 return (__force __be32)tun_id;
239 #else
240 return (__force __be32)((__force u64)tun_id >> 32);
241 #endif
242 }
243
244 #ifdef CONFIG_INET
245
246 int ip_tunnel_init(struct net_device *dev);
247 void ip_tunnel_uninit(struct net_device *dev);
248 void ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
249 struct net *ip_tunnel_get_link_net(const struct net_device *dev);
250 int ip_tunnel_get_iflink(const struct net_device *dev);
251 int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
252 struct rtnl_link_ops *ops, char *devname);
253
254 void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);
255
256 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
257 const struct iphdr *tnl_params, const u8 protocol);
258 void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
259 const u8 proto);
260 int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
261 int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
262 int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
263
264 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
265 struct rtnl_link_stats64 *tot);
266 struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
267 int link, __be16 flags,
268 __be32 remote, __be32 local,
269 __be32 key);
270
271 int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
272 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
273 bool log_ecn_error);
274 int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
275 struct ip_tunnel_parm *p);
276 int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
277 struct ip_tunnel_parm *p);
278 void ip_tunnel_setup(struct net_device *dev, int net_id);
279
280 struct ip_tunnel_encap_ops {
281 size_t (*encap_hlen)(struct ip_tunnel_encap *e);
282 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
283 u8 *protocol, struct flowi4 *fl4);
284 };
285
286 #define MAX_IPTUN_ENCAP_OPS 8
287
288 extern const struct ip_tunnel_encap_ops __rcu *
289 iptun_encaps[MAX_IPTUN_ENCAP_OPS];
290
291 int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
292 unsigned int num);
293 int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
294 unsigned int num);
295
296 int ip_tunnel_encap_setup(struct ip_tunnel *t,
297 struct ip_tunnel_encap *ipencap);
298
ip_encap_hlen(struct ip_tunnel_encap * e)299 static inline int ip_encap_hlen(struct ip_tunnel_encap *e)
300 {
301 const struct ip_tunnel_encap_ops *ops;
302 int hlen = -EINVAL;
303
304 if (e->type == TUNNEL_ENCAP_NONE)
305 return 0;
306
307 if (e->type >= MAX_IPTUN_ENCAP_OPS)
308 return -EINVAL;
309
310 rcu_read_lock();
311 ops = rcu_dereference(iptun_encaps[e->type]);
312 if (likely(ops && ops->encap_hlen))
313 hlen = ops->encap_hlen(e);
314 rcu_read_unlock();
315
316 return hlen;
317 }
318
ip_tunnel_encap(struct sk_buff * skb,struct ip_tunnel * t,u8 * protocol,struct flowi4 * fl4)319 static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
320 u8 *protocol, struct flowi4 *fl4)
321 {
322 const struct ip_tunnel_encap_ops *ops;
323 int ret = -EINVAL;
324
325 if (t->encap.type == TUNNEL_ENCAP_NONE)
326 return 0;
327
328 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
329 return -EINVAL;
330
331 rcu_read_lock();
332 ops = rcu_dereference(iptun_encaps[t->encap.type]);
333 if (likely(ops && ops->build_header))
334 ret = ops->build_header(skb, &t->encap, protocol, fl4);
335 rcu_read_unlock();
336
337 return ret;
338 }
339
340 /* Extract dsfield from inner protocol */
ip_tunnel_get_dsfield(const struct iphdr * iph,const struct sk_buff * skb)341 static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
342 const struct sk_buff *skb)
343 {
344 if (skb->protocol == htons(ETH_P_IP))
345 return iph->tos;
346 else if (skb->protocol == htons(ETH_P_IPV6))
347 return ipv6_get_dsfield((const struct ipv6hdr *)iph);
348 else
349 return 0;
350 }
351
352 /* Propogate ECN bits out */
ip_tunnel_ecn_encap(u8 tos,const struct iphdr * iph,const struct sk_buff * skb)353 static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
354 const struct sk_buff *skb)
355 {
356 u8 inner = ip_tunnel_get_dsfield(iph, skb);
357
358 return INET_ECN_encapsulate(tos, inner);
359 }
360
361 int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
362 __be16 inner_proto, bool raw_proto, bool xnet);
363
iptunnel_pull_header(struct sk_buff * skb,int hdr_len,__be16 inner_proto,bool xnet)364 static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
365 __be16 inner_proto, bool xnet)
366 {
367 return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);
368 }
369
370 void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
371 __be32 src, __be32 dst, u8 proto,
372 u8 tos, u8 ttl, __be16 df, bool xnet);
373 struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
374 gfp_t flags);
375
376 int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask);
377
iptunnel_pull_offloads(struct sk_buff * skb)378 static inline int iptunnel_pull_offloads(struct sk_buff *skb)
379 {
380 if (skb_is_gso(skb)) {
381 int err;
382
383 err = skb_unclone(skb, GFP_ATOMIC);
384 if (unlikely(err))
385 return err;
386 skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >>
387 NETIF_F_GSO_SHIFT);
388 }
389
390 skb->encapsulation = 0;
391 return 0;
392 }
393
iptunnel_xmit_stats(struct net_device * dev,int pkt_len)394 static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len)
395 {
396 if (pkt_len > 0) {
397 struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);
398
399 u64_stats_update_begin(&tstats->syncp);
400 tstats->tx_bytes += pkt_len;
401 tstats->tx_packets++;
402 u64_stats_update_end(&tstats->syncp);
403 put_cpu_ptr(tstats);
404 } else {
405 struct net_device_stats *err_stats = &dev->stats;
406
407 if (pkt_len < 0) {
408 err_stats->tx_errors++;
409 err_stats->tx_aborted_errors++;
410 } else {
411 err_stats->tx_dropped++;
412 }
413 }
414 }
415
ip_tunnel_info_opts(struct ip_tunnel_info * info)416 static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info)
417 {
418 return info + 1;
419 }
420
ip_tunnel_info_opts_get(void * to,const struct ip_tunnel_info * info)421 static inline void ip_tunnel_info_opts_get(void *to,
422 const struct ip_tunnel_info *info)
423 {
424 memcpy(to, info + 1, info->options_len);
425 }
426
ip_tunnel_info_opts_set(struct ip_tunnel_info * info,const void * from,int len)427 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
428 const void *from, int len)
429 {
430 memcpy(ip_tunnel_info_opts(info), from, len);
431 info->options_len = len;
432 }
433
lwt_tun_info(struct lwtunnel_state * lwtstate)434 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
435 {
436 return (struct ip_tunnel_info *)lwtstate->data;
437 }
438
439 extern struct static_key ip_tunnel_metadata_cnt;
440
441 /* Returns > 0 if metadata should be collected */
ip_tunnel_collect_metadata(void)442 static inline int ip_tunnel_collect_metadata(void)
443 {
444 return static_key_false(&ip_tunnel_metadata_cnt);
445 }
446
447 void __init ip_tunnel_core_init(void);
448
449 void ip_tunnel_need_metadata(void);
450 void ip_tunnel_unneed_metadata(void);
451
452 #else /* CONFIG_INET */
453
lwt_tun_info(struct lwtunnel_state * lwtstate)454 static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
455 {
456 return NULL;
457 }
458
ip_tunnel_need_metadata(void)459 static inline void ip_tunnel_need_metadata(void)
460 {
461 }
462
ip_tunnel_unneed_metadata(void)463 static inline void ip_tunnel_unneed_metadata(void)
464 {
465 }
466
ip_tunnel_info_opts_get(void * to,const struct ip_tunnel_info * info)467 static inline void ip_tunnel_info_opts_get(void *to,
468 const struct ip_tunnel_info *info)
469 {
470 }
471
ip_tunnel_info_opts_set(struct ip_tunnel_info * info,const void * from,int len)472 static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
473 const void *from, int len)
474 {
475 info->options_len = 0;
476 }
477
478 #endif /* CONFIG_INET */
479
480 #endif /* __NET_IP_TUNNELS_H */
481