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Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NET_IP_TUNNELS_H
3#define __NET_IP_TUNNELS_H 1
4
5#include <linux/if_tunnel.h>
6#include <linux/netdevice.h>
7#include <linux/skbuff.h>
8#include <linux/socket.h>
9#include <linux/types.h>
10#include <linux/u64_stats_sync.h>
11#include <linux/bitops.h>
12
13#include <net/dsfield.h>
14#include <net/gro_cells.h>
15#include <net/inet_ecn.h>
16#include <net/netns/generic.h>
17#include <net/rtnetlink.h>
18#include <net/lwtunnel.h>
19#include <net/dst_cache.h>
20
21#if IS_ENABLED(CONFIG_IPV6)
22#include <net/ipv6.h>
23#include <net/ip6_fib.h>
24#include <net/ip6_route.h>
25#endif
26
27/* Keep error state on tunnel for 30 sec */
28#define IPTUNNEL_ERR_TIMEO (30*HZ)
29
30/* Used to memset ip_tunnel padding. */
31#define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst)
32
33/* Used to memset ipv4 address padding. */
34#define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst)
35#define IP_TUNNEL_KEY_IPV4_PAD_LEN \
36 (sizeof_field(struct ip_tunnel_key, u) - \
37 sizeof_field(struct ip_tunnel_key, u.ipv4))
38
39struct ip_tunnel_key {
40 __be64 tun_id;
41 union {
42 struct {
43 __be32 src;
44 __be32 dst;
45 } ipv4;
46 struct {
47 struct in6_addr src;
48 struct in6_addr dst;
49 } ipv6;
50 } u;
51 __be16 tun_flags;
52 u8 tos; /* TOS for IPv4, TC for IPv6 */
53 u8 ttl; /* TTL for IPv4, HL for IPv6 */
54 __be32 label; /* Flow Label for IPv6 */
55 __be16 tp_src;
56 __be16 tp_dst;
57};
58
59/* Flags for ip_tunnel_info mode. */
60#define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */
61#define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */
62#define IP_TUNNEL_INFO_BRIDGE 0x04 /* represents a bridged tunnel id */
63
64/* Maximum tunnel options length. */
65#define IP_TUNNEL_OPTS_MAX \
66 GENMASK((sizeof_field(struct ip_tunnel_info, \
67 options_len) * BITS_PER_BYTE) - 1, 0)
68
69struct ip_tunnel_info {
70 struct ip_tunnel_key key;
71#ifdef CONFIG_DST_CACHE
72 struct dst_cache dst_cache;
73#endif
74 u8 options_len;
75 u8 mode;
76};
77
78/* 6rd prefix/relay information */
79#ifdef CONFIG_IPV6_SIT_6RD
80struct ip_tunnel_6rd_parm {
81 struct in6_addr prefix;
82 __be32 relay_prefix;
83 u16 prefixlen;
84 u16 relay_prefixlen;
85};
86#endif
87
88struct ip_tunnel_encap {
89 u16 type;
90 u16 flags;
91 __be16 sport;
92 __be16 dport;
93};
94
95struct ip_tunnel_prl_entry {
96 struct ip_tunnel_prl_entry __rcu *next;
97 __be32 addr;
98 u16 flags;
99 struct rcu_head rcu_head;
100};
101
102struct metadata_dst;
103
104struct ip_tunnel {
105 struct ip_tunnel __rcu *next;
106 struct hlist_node hash_node;
107
108 struct net_device *dev;
109 netdevice_tracker dev_tracker;
110
111 struct net *net; /* netns for packet i/o */
112
113 unsigned long err_time; /* Time when the last ICMP error
114 * arrived */
115 int err_count; /* Number of arrived ICMP errors */
116
117 /* These four fields used only by GRE */
118 u32 i_seqno; /* The last seen seqno */
119 u32 o_seqno; /* The last output seqno */
120 int tun_hlen; /* Precalculated header length */
121
122 /* These four fields used only by ERSPAN */
123 u32 index; /* ERSPAN type II index */
124 u8 erspan_ver; /* ERSPAN version */
125 u8 dir; /* ERSPAN direction */
126 u16 hwid; /* ERSPAN hardware ID */
127
128 struct dst_cache dst_cache;
129
130 struct ip_tunnel_parm parms;
131
132 int mlink;
133 int encap_hlen; /* Encap header length (FOU,GUE) */
134 int hlen; /* tun_hlen + encap_hlen */
135 struct ip_tunnel_encap encap;
136
137 /* for SIT */
138#ifdef CONFIG_IPV6_SIT_6RD
139 struct ip_tunnel_6rd_parm ip6rd;
140#endif
141 struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */
142 unsigned int prl_count; /* # of entries in PRL */
143 unsigned int ip_tnl_net_id;
144 struct gro_cells gro_cells;
145 __u32 fwmark;
146 bool collect_md;
147 bool ignore_df;
148};
149
150struct tnl_ptk_info {
151 __be16 flags;
152 __be16 proto;
153 __be32 key;
154 __be32 seq;
155 int hdr_len;
156};
157
158#define PACKET_RCVD 0
159#define PACKET_REJECT 1
160#define PACKET_NEXT 2
161
162#define IP_TNL_HASH_BITS 7
163#define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS)
164
165struct ip_tunnel_net {
166 struct net_device *fb_tunnel_dev;
167 struct rtnl_link_ops *rtnl_link_ops;
168 struct hlist_head tunnels[IP_TNL_HASH_SIZE];
169 struct ip_tunnel __rcu *collect_md_tun;
170 int type;
171};
172
173static inline void ip_tunnel_key_init(struct ip_tunnel_key *key,
174 __be32 saddr, __be32 daddr,
175 u8 tos, u8 ttl, __be32 label,
176 __be16 tp_src, __be16 tp_dst,
177 __be64 tun_id, __be16 tun_flags)
178{
179 key->tun_id = tun_id;
180 key->u.ipv4.src = saddr;
181 key->u.ipv4.dst = daddr;
182 memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD,
183 0, IP_TUNNEL_KEY_IPV4_PAD_LEN);
184 key->tos = tos;
185 key->ttl = ttl;
186 key->label = label;
187 key->tun_flags = tun_flags;
188
189 /* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
190 * the upper tunnel are used.
191 * E.g: GRE over IPSEC, the tp_src and tp_port are zero.
192 */
193 key->tp_src = tp_src;
194 key->tp_dst = tp_dst;
195
196 /* Clear struct padding. */
197 if (sizeof(*key) != IP_TUNNEL_KEY_SIZE)
198 memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE,
199 0, sizeof(*key) - IP_TUNNEL_KEY_SIZE);
200}
201
202static inline bool
203ip_tunnel_dst_cache_usable(const struct sk_buff *skb,
204 const struct ip_tunnel_info *info)
205{
206 if (skb->mark)
207 return false;
208 if (!info)
209 return true;
210 if (info->key.tun_flags & TUNNEL_NOCACHE)
211 return false;
212
213 return true;
214}
215
216static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info
217 *tun_info)
218{
219 return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET;
220}
221
222static inline __be64 key32_to_tunnel_id(__be32 key)
223{
224#ifdef __BIG_ENDIAN
225 return (__force __be64)key;
226#else
227 return (__force __be64)((__force u64)key << 32);
228#endif
229}
230
231/* Returns the least-significant 32 bits of a __be64. */
232static inline __be32 tunnel_id_to_key32(__be64 tun_id)
233{
234#ifdef __BIG_ENDIAN
235 return (__force __be32)tun_id;
236#else
237 return (__force __be32)((__force u64)tun_id >> 32);
238#endif
239}
240
241#ifdef CONFIG_INET
242
243static inline void ip_tunnel_init_flow(struct flowi4 *fl4,
244 int proto,
245 __be32 daddr, __be32 saddr,
246 __be32 key, __u8 tos, int oif,
247 __u32 mark, __u32 tun_inner_hash)
248{
249 memset(fl4, 0, sizeof(*fl4));
250 fl4->flowi4_oif = oif;
251 fl4->daddr = daddr;
252 fl4->saddr = saddr;
253 fl4->flowi4_tos = tos;
254 fl4->flowi4_proto = proto;
255 fl4->fl4_gre_key = key;
256 fl4->flowi4_mark = mark;
257 fl4->flowi4_multipath_hash = tun_inner_hash;
258}
259
260int ip_tunnel_init(struct net_device *dev);
261void ip_tunnel_uninit(struct net_device *dev);
262void ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
263struct net *ip_tunnel_get_link_net(const struct net_device *dev);
264int ip_tunnel_get_iflink(const struct net_device *dev);
265int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id,
266 struct rtnl_link_ops *ops, char *devname);
267
268void ip_tunnel_delete_nets(struct list_head *list_net, unsigned int id,
269 struct rtnl_link_ops *ops);
270
271void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
272 const struct iphdr *tnl_params, const u8 protocol);
273void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
274 const u8 proto, int tunnel_hlen);
275int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
276int ip_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
277 void __user *data, int cmd);
278int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
279int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
280
281struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
282 int link, __be16 flags,
283 __be32 remote, __be32 local,
284 __be32 key);
285
286int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
287 const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
288 bool log_ecn_error);
289int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
290 struct ip_tunnel_parm *p, __u32 fwmark);
291int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
292 struct ip_tunnel_parm *p, __u32 fwmark);
293void ip_tunnel_setup(struct net_device *dev, unsigned int net_id);
294
295extern const struct header_ops ip_tunnel_header_ops;
296__be16 ip_tunnel_parse_protocol(const struct sk_buff *skb);
297
298struct ip_tunnel_encap_ops {
299 size_t (*encap_hlen)(struct ip_tunnel_encap *e);
300 int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
301 u8 *protocol, struct flowi4 *fl4);
302 int (*err_handler)(struct sk_buff *skb, u32 info);
303};
304
305#define MAX_IPTUN_ENCAP_OPS 8
306
307extern const struct ip_tunnel_encap_ops __rcu *
308 iptun_encaps[MAX_IPTUN_ENCAP_OPS];
309
310int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
311 unsigned int num);
312int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
313 unsigned int num);
314
315int ip_tunnel_encap_setup(struct ip_tunnel *t,
316 struct ip_tunnel_encap *ipencap);
317
318static inline bool pskb_inet_may_pull(struct sk_buff *skb)
319{
320 int nhlen;
321
322 switch (skb->protocol) {
323#if IS_ENABLED(CONFIG_IPV6)
324 case htons(ETH_P_IPV6):
325 nhlen = sizeof(struct ipv6hdr);
326 break;
327#endif
328 case htons(ETH_P_IP):
329 nhlen = sizeof(struct iphdr);
330 break;
331 default:
332 nhlen = 0;
333 }
334
335 return pskb_network_may_pull(skb, nhlen);
336}
337
338static inline int ip_encap_hlen(struct ip_tunnel_encap *e)
339{
340 const struct ip_tunnel_encap_ops *ops;
341 int hlen = -EINVAL;
342
343 if (e->type == TUNNEL_ENCAP_NONE)
344 return 0;
345
346 if (e->type >= MAX_IPTUN_ENCAP_OPS)
347 return -EINVAL;
348
349 rcu_read_lock();
350 ops = rcu_dereference(iptun_encaps[e->type]);
351 if (likely(ops && ops->encap_hlen))
352 hlen = ops->encap_hlen(e);
353 rcu_read_unlock();
354
355 return hlen;
356}
357
358static inline int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
359 u8 *protocol, struct flowi4 *fl4)
360{
361 const struct ip_tunnel_encap_ops *ops;
362 int ret = -EINVAL;
363
364 if (t->encap.type == TUNNEL_ENCAP_NONE)
365 return 0;
366
367 if (t->encap.type >= MAX_IPTUN_ENCAP_OPS)
368 return -EINVAL;
369
370 rcu_read_lock();
371 ops = rcu_dereference(iptun_encaps[t->encap.type]);
372 if (likely(ops && ops->build_header))
373 ret = ops->build_header(skb, &t->encap, protocol, fl4);
374 rcu_read_unlock();
375
376 return ret;
377}
378
379/* Extract dsfield from inner protocol */
380static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
381 const struct sk_buff *skb)
382{
383 if (skb->protocol == htons(ETH_P_IP))
384 return iph->tos;
385 else if (skb->protocol == htons(ETH_P_IPV6))
386 return ipv6_get_dsfield((const struct ipv6hdr *)iph);
387 else
388 return 0;
389}
390
391static inline u8 ip_tunnel_get_ttl(const struct iphdr *iph,
392 const struct sk_buff *skb)
393{
394 if (skb->protocol == htons(ETH_P_IP))
395 return iph->ttl;
396 else if (skb->protocol == htons(ETH_P_IPV6))
397 return ((const struct ipv6hdr *)iph)->hop_limit;
398 else
399 return 0;
400}
401
402/* Propogate ECN bits out */
403static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
404 const struct sk_buff *skb)
405{
406 u8 inner = ip_tunnel_get_dsfield(iph, skb);
407
408 return INET_ECN_encapsulate(tos, inner);
409}
410
411int __iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
412 __be16 inner_proto, bool raw_proto, bool xnet);
413
414static inline int iptunnel_pull_header(struct sk_buff *skb, int hdr_len,
415 __be16 inner_proto, bool xnet)
416{
417 return __iptunnel_pull_header(skb, hdr_len, inner_proto, false, xnet);
418}
419
420void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
421 __be32 src, __be32 dst, u8 proto,
422 u8 tos, u8 ttl, __be16 df, bool xnet);
423struct metadata_dst *iptunnel_metadata_reply(struct metadata_dst *md,
424 gfp_t flags);
425int skb_tunnel_check_pmtu(struct sk_buff *skb, struct dst_entry *encap_dst,
426 int headroom, bool reply);
427
428int iptunnel_handle_offloads(struct sk_buff *skb, int gso_type_mask);
429
430static inline int iptunnel_pull_offloads(struct sk_buff *skb)
431{
432 if (skb_is_gso(skb)) {
433 int err;
434
435 err = skb_unclone(skb, GFP_ATOMIC);
436 if (unlikely(err))
437 return err;
438 skb_shinfo(skb)->gso_type &= ~(NETIF_F_GSO_ENCAP_ALL >>
439 NETIF_F_GSO_SHIFT);
440 }
441
442 skb->encapsulation = 0;
443 return 0;
444}
445
446static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len)
447{
448 if (pkt_len > 0) {
449 struct pcpu_sw_netstats *tstats = get_cpu_ptr(dev->tstats);
450
451 u64_stats_update_begin(&tstats->syncp);
452 tstats->tx_bytes += pkt_len;
453 tstats->tx_packets++;
454 u64_stats_update_end(&tstats->syncp);
455 put_cpu_ptr(tstats);
456 } else {
457 struct net_device_stats *err_stats = &dev->stats;
458
459 if (pkt_len < 0) {
460 err_stats->tx_errors++;
461 err_stats->tx_aborted_errors++;
462 } else {
463 err_stats->tx_dropped++;
464 }
465 }
466}
467
468static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info)
469{
470 return info + 1;
471}
472
473static inline void ip_tunnel_info_opts_get(void *to,
474 const struct ip_tunnel_info *info)
475{
476 memcpy(to, info + 1, info->options_len);
477}
478
479static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
480 const void *from, int len,
481 __be16 flags)
482{
483 info->options_len = len;
484 if (len > 0) {
485 memcpy(ip_tunnel_info_opts(info), from, len);
486 info->key.tun_flags |= flags;
487 }
488}
489
490static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
491{
492 return (struct ip_tunnel_info *)lwtstate->data;
493}
494
495DECLARE_STATIC_KEY_FALSE(ip_tunnel_metadata_cnt);
496
497/* Returns > 0 if metadata should be collected */
498static inline int ip_tunnel_collect_metadata(void)
499{
500 return static_branch_unlikely(&ip_tunnel_metadata_cnt);
501}
502
503void __init ip_tunnel_core_init(void);
504
505void ip_tunnel_need_metadata(void);
506void ip_tunnel_unneed_metadata(void);
507
508#else /* CONFIG_INET */
509
510static inline struct ip_tunnel_info *lwt_tun_info(struct lwtunnel_state *lwtstate)
511{
512 return NULL;
513}
514
515static inline void ip_tunnel_need_metadata(void)
516{
517}
518
519static inline void ip_tunnel_unneed_metadata(void)
520{
521}
522
523static inline void ip_tunnel_info_opts_get(void *to,
524 const struct ip_tunnel_info *info)
525{
526}
527
528static inline void ip_tunnel_info_opts_set(struct ip_tunnel_info *info,
529 const void *from, int len,
530 __be16 flags)
531{
532 info->options_len = 0;
533}
534
535#endif /* CONFIG_INET */
536
537#endif /* __NET_IP_TUNNELS_H */