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