1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NET_VXLAN_H
3#define __NET_VXLAN_H 1
4
5#include <linux/if_vlan.h>
6#include <net/udp_tunnel.h>
7#include <net/dst_metadata.h>
8#include <net/rtnetlink.h>
9#include <net/switchdev.h>
10
11/* VXLAN protocol (RFC 7348) header:
12 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
13 * |R|R|R|R|I|R|R|R| Reserved |
14 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
15 * | VXLAN Network Identifier (VNI) | Reserved |
16 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
17 *
18 * I = VXLAN Network Identifier (VNI) present.
19 */
20struct vxlanhdr {
21 __be32 vx_flags;
22 __be32 vx_vni;
23};
24
25/* VXLAN header flags. */
26#define VXLAN_HF_VNI cpu_to_be32(BIT(27))
27
28#define VXLAN_N_VID (1u << 24)
29#define VXLAN_VID_MASK (VXLAN_N_VID - 1)
30#define VXLAN_VNI_MASK cpu_to_be32(VXLAN_VID_MASK << 8)
31#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
32
33#define VNI_HASH_BITS 10
34#define VNI_HASH_SIZE (1<<VNI_HASH_BITS)
35#define FDB_HASH_BITS 8
36#define FDB_HASH_SIZE (1<<FDB_HASH_BITS)
37
38/* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40 * |R|R|R|R|I|R|R|R|R|R|C| Reserved |
41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 * | VXLAN Network Identifier (VNI) |O| Csum start |
43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44 *
45 * C = Remote checksum offload bit. When set indicates that the
46 * remote checksum offload data is present.
47 *
48 * O = Offset bit. Indicates the checksum offset relative to
49 * checksum start.
50 *
51 * Csum start = Checksum start divided by two.
52 *
53 * http://tools.ietf.org/html/draft-herbert-vxlan-rco
54 */
55
56/* VXLAN-RCO header flags. */
57#define VXLAN_HF_RCO cpu_to_be32(BIT(21))
58
59/* Remote checksum offload header option */
60#define VXLAN_RCO_MASK cpu_to_be32(0x7f) /* Last byte of vni field */
61#define VXLAN_RCO_UDP cpu_to_be32(0x80) /* Indicate UDP RCO (TCP when not set *) */
62#define VXLAN_RCO_SHIFT 1 /* Left shift of start */
63#define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
64#define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)
65
66/*
67 * VXLAN Group Based Policy Extension (VXLAN_F_GBP):
68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID |
70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * | VXLAN Network Identifier (VNI) | Reserved |
72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 *
74 * G = Group Policy ID present.
75 *
76 * D = Don't Learn bit. When set, this bit indicates that the egress
77 * VTEP MUST NOT learn the source address of the encapsulated frame.
78 *
79 * A = Indicates that the group policy has already been applied to
80 * this packet. Policies MUST NOT be applied by devices when the
81 * A bit is set.
82 *
83 * https://tools.ietf.org/html/draft-smith-vxlan-group-policy
84 */
85struct vxlanhdr_gbp {
86 u8 vx_flags;
87#ifdef __LITTLE_ENDIAN_BITFIELD
88 u8 reserved_flags1:3,
89 policy_applied:1,
90 reserved_flags2:2,
91 dont_learn:1,
92 reserved_flags3:1;
93#elif defined(__BIG_ENDIAN_BITFIELD)
94 u8 reserved_flags1:1,
95 dont_learn:1,
96 reserved_flags2:2,
97 policy_applied:1,
98 reserved_flags3:3;
99#else
100#error "Please fix <asm/byteorder.h>"
101#endif
102 __be16 policy_id;
103 __be32 vx_vni;
104};
105
106/* VXLAN-GBP header flags. */
107#define VXLAN_HF_GBP cpu_to_be32(BIT(31))
108
109#define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF))
110
111/* skb->mark mapping
112 *
113 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
114 * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID |
115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
116 */
117#define VXLAN_GBP_DONT_LEARN (BIT(6) << 16)
118#define VXLAN_GBP_POLICY_APPLIED (BIT(3) << 16)
119#define VXLAN_GBP_ID_MASK (0xFFFF)
120
121/*
122 * VXLAN Generic Protocol Extension (VXLAN_F_GPE):
123 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
124 * |R|R|Ver|I|P|R|O| Reserved |Next Protocol |
125 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126 * | VXLAN Network Identifier (VNI) | Reserved |
127 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
128 *
129 * Ver = Version. Indicates VXLAN GPE protocol version.
130 *
131 * P = Next Protocol Bit. The P bit is set to indicate that the
132 * Next Protocol field is present.
133 *
134 * O = OAM Flag Bit. The O bit is set to indicate that the packet
135 * is an OAM packet.
136 *
137 * Next Protocol = This 8 bit field indicates the protocol header
138 * immediately following the VXLAN GPE header.
139 *
140 * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
141 */
142
143struct vxlanhdr_gpe {
144#if defined(__LITTLE_ENDIAN_BITFIELD)
145 u8 oam_flag:1,
146 reserved_flags1:1,
147 np_applied:1,
148 instance_applied:1,
149 version:2,
150 reserved_flags2:2;
151#elif defined(__BIG_ENDIAN_BITFIELD)
152 u8 reserved_flags2:2,
153 version:2,
154 instance_applied:1,
155 np_applied:1,
156 reserved_flags1:1,
157 oam_flag:1;
158#endif
159 u8 reserved_flags3;
160 u8 reserved_flags4;
161 u8 next_protocol;
162 __be32 vx_vni;
163};
164
165/* VXLAN-GPE header flags. */
166#define VXLAN_HF_VER cpu_to_be32(BIT(29) | BIT(28))
167#define VXLAN_HF_NP cpu_to_be32(BIT(26))
168#define VXLAN_HF_OAM cpu_to_be32(BIT(24))
169
170#define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \
171 cpu_to_be32(0xff))
172
173struct vxlan_metadata {
174 u32 gbp;
175};
176
177/* per UDP socket information */
178struct vxlan_sock {
179 struct hlist_node hlist;
180 struct socket *sock;
181 struct hlist_head vni_list[VNI_HASH_SIZE];
182 refcount_t refcnt;
183 u32 flags;
184};
185
186union vxlan_addr {
187 struct sockaddr_in sin;
188 struct sockaddr_in6 sin6;
189 struct sockaddr sa;
190};
191
192struct vxlan_rdst {
193 union vxlan_addr remote_ip;
194 __be16 remote_port;
195 u8 offloaded:1;
196 __be32 remote_vni;
197 u32 remote_ifindex;
198 struct list_head list;
199 struct rcu_head rcu;
200 struct dst_cache dst_cache;
201};
202
203struct vxlan_config {
204 union vxlan_addr remote_ip;
205 union vxlan_addr saddr;
206 __be32 vni;
207 int remote_ifindex;
208 int mtu;
209 __be16 dst_port;
210 u16 port_min;
211 u16 port_max;
212 u8 tos;
213 u8 ttl;
214 __be32 label;
215 u32 flags;
216 unsigned long age_interval;
217 unsigned int addrmax;
218 bool no_share;
219 enum ifla_vxlan_df df;
220};
221
222struct vxlan_dev_node {
223 struct hlist_node hlist;
224 struct vxlan_dev *vxlan;
225};
226
227/* Pseudo network device */
228struct vxlan_dev {
229 struct vxlan_dev_node hlist4; /* vni hash table for IPv4 socket */
230#if IS_ENABLED(CONFIG_IPV6)
231 struct vxlan_dev_node hlist6; /* vni hash table for IPv6 socket */
232#endif
233 struct list_head next; /* vxlan's per namespace list */
234 struct vxlan_sock __rcu *vn4_sock; /* listening socket for IPv4 */
235#if IS_ENABLED(CONFIG_IPV6)
236 struct vxlan_sock __rcu *vn6_sock; /* listening socket for IPv6 */
237#endif
238 struct net_device *dev;
239 struct net *net; /* netns for packet i/o */
240 struct vxlan_rdst default_dst; /* default destination */
241
242 struct timer_list age_timer;
243 spinlock_t hash_lock;
244 unsigned int addrcnt;
245 struct gro_cells gro_cells;
246
247 struct vxlan_config cfg;
248
249 struct hlist_head fdb_head[FDB_HASH_SIZE];
250};
251
252#define VXLAN_F_LEARN 0x01
253#define VXLAN_F_PROXY 0x02
254#define VXLAN_F_RSC 0x04
255#define VXLAN_F_L2MISS 0x08
256#define VXLAN_F_L3MISS 0x10
257#define VXLAN_F_IPV6 0x20
258#define VXLAN_F_UDP_ZERO_CSUM_TX 0x40
259#define VXLAN_F_UDP_ZERO_CSUM6_TX 0x80
260#define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100
261#define VXLAN_F_REMCSUM_TX 0x200
262#define VXLAN_F_REMCSUM_RX 0x400
263#define VXLAN_F_GBP 0x800
264#define VXLAN_F_REMCSUM_NOPARTIAL 0x1000
265#define VXLAN_F_COLLECT_METADATA 0x2000
266#define VXLAN_F_GPE 0x4000
267#define VXLAN_F_IPV6_LINKLOCAL 0x8000
268#define VXLAN_F_TTL_INHERIT 0x10000
269
270/* Flags that are used in the receive path. These flags must match in
271 * order for a socket to be shareable
272 */
273#define VXLAN_F_RCV_FLAGS (VXLAN_F_GBP | \
274 VXLAN_F_GPE | \
275 VXLAN_F_UDP_ZERO_CSUM6_RX | \
276 VXLAN_F_REMCSUM_RX | \
277 VXLAN_F_REMCSUM_NOPARTIAL | \
278 VXLAN_F_COLLECT_METADATA)
279
280/* Flags that can be set together with VXLAN_F_GPE. */
281#define VXLAN_F_ALLOWED_GPE (VXLAN_F_GPE | \
282 VXLAN_F_IPV6 | \
283 VXLAN_F_IPV6_LINKLOCAL | \
284 VXLAN_F_UDP_ZERO_CSUM_TX | \
285 VXLAN_F_UDP_ZERO_CSUM6_TX | \
286 VXLAN_F_UDP_ZERO_CSUM6_RX | \
287 VXLAN_F_COLLECT_METADATA)
288
289struct net_device *vxlan_dev_create(struct net *net, const char *name,
290 u8 name_assign_type, struct vxlan_config *conf);
291
292static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
293 netdev_features_t features)
294{
295 u8 l4_hdr = 0;
296
297 if (!skb->encapsulation)
298 return features;
299
300 switch (vlan_get_protocol(skb)) {
301 case htons(ETH_P_IP):
302 l4_hdr = ip_hdr(skb)->protocol;
303 break;
304 case htons(ETH_P_IPV6):
305 l4_hdr = ipv6_hdr(skb)->nexthdr;
306 break;
307 default:
308 return features;
309 }
310
311 if ((l4_hdr == IPPROTO_UDP) &&
312 (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
313 skb->inner_protocol != htons(ETH_P_TEB) ||
314 (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
315 sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
316 (skb->ip_summed != CHECKSUM_NONE &&
317 !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
318 return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
319
320 return features;
321}
322
323/* IP header + UDP + VXLAN + Ethernet header */
324#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
325/* IPv6 header + UDP + VXLAN + Ethernet header */
326#define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
327
328static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
329{
330 return (struct vxlanhdr *)(udp_hdr(skb) + 1);
331}
332
333static inline __be32 vxlan_vni(__be32 vni_field)
334{
335#if defined(__BIG_ENDIAN)
336 return (__force __be32)((__force u32)vni_field >> 8);
337#else
338 return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
339#endif
340}
341
342static inline __be32 vxlan_vni_field(__be32 vni)
343{
344#if defined(__BIG_ENDIAN)
345 return (__force __be32)((__force u32)vni << 8);
346#else
347 return (__force __be32)((__force u32)vni >> 8);
348#endif
349}
350
351static inline size_t vxlan_rco_start(__be32 vni_field)
352{
353 return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
354}
355
356static inline size_t vxlan_rco_offset(__be32 vni_field)
357{
358 return (vni_field & VXLAN_RCO_UDP) ?
359 offsetof(struct udphdr, check) :
360 offsetof(struct tcphdr, check);
361}
362
363static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
364{
365 __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);
366
367 if (offset == offsetof(struct udphdr, check))
368 vni_field |= VXLAN_RCO_UDP;
369 return vni_field;
370}
371
372static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
373{
374 return vs->sock->sk->sk_family;
375}
376
377#if IS_ENABLED(CONFIG_IPV6)
378
379static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
380{
381 if (ipa->sa.sa_family == AF_INET6)
382 return ipv6_addr_any(&ipa->sin6.sin6_addr);
383 else
384 return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
385}
386
387static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
388{
389 if (ipa->sa.sa_family == AF_INET6)
390 return ipv6_addr_is_multicast(&ipa->sin6.sin6_addr);
391 else
392 return IN_MULTICAST(ntohl(ipa->sin.sin_addr.s_addr));
393}
394
395#else /* !IS_ENABLED(CONFIG_IPV6) */
396
397static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
398{
399 return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
400}
401
402static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
403{
404 return IN_MULTICAST(ntohl(ipa->sin.sin_addr.s_addr));
405}
406
407#endif /* IS_ENABLED(CONFIG_IPV6) */
408
409static inline bool netif_is_vxlan(const struct net_device *dev)
410{
411 return dev->rtnl_link_ops &&
412 !strcmp(dev->rtnl_link_ops->kind, "vxlan");
413}
414
415struct switchdev_notifier_vxlan_fdb_info {
416 struct switchdev_notifier_info info; /* must be first */
417 union vxlan_addr remote_ip;
418 __be16 remote_port;
419 __be32 remote_vni;
420 u32 remote_ifindex;
421 u8 eth_addr[ETH_ALEN];
422 __be32 vni;
423 bool offloaded;
424 bool added_by_user;
425};
426
427#if IS_ENABLED(CONFIG_VXLAN)
428int vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
429 struct switchdev_notifier_vxlan_fdb_info *fdb_info);
430int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
431 struct notifier_block *nb,
432 struct netlink_ext_ack *extack);
433void vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni);
434
435#else
436static inline int
437vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
438 struct switchdev_notifier_vxlan_fdb_info *fdb_info)
439{
440 return -ENOENT;
441}
442
443static inline int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
444 struct notifier_block *nb,
445 struct netlink_ext_ack *extack)
446{
447 return -EOPNOTSUPP;
448}
449
450static inline void
451vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni)
452{
453}
454#endif
455
456static inline void vxlan_flag_attr_error(int attrtype,
457 struct netlink_ext_ack *extack)
458{
459#define VXLAN_FLAG(flg) \
460 case IFLA_VXLAN_##flg: \
461 NL_SET_ERR_MSG_MOD(extack, \
462 "cannot change " #flg " flag"); \
463 break
464 switch (attrtype) {
465 VXLAN_FLAG(TTL_INHERIT);
466 VXLAN_FLAG(LEARNING);
467 VXLAN_FLAG(PROXY);
468 VXLAN_FLAG(RSC);
469 VXLAN_FLAG(L2MISS);
470 VXLAN_FLAG(L3MISS);
471 VXLAN_FLAG(COLLECT_METADATA);
472 VXLAN_FLAG(UDP_ZERO_CSUM6_TX);
473 VXLAN_FLAG(UDP_ZERO_CSUM6_RX);
474 VXLAN_FLAG(REMCSUM_TX);
475 VXLAN_FLAG(REMCSUM_RX);
476 VXLAN_FLAG(GBP);
477 VXLAN_FLAG(GPE);
478 VXLAN_FLAG(REMCSUM_NOPARTIAL);
479 default:
480 NL_SET_ERR_MSG_MOD(extack, \
481 "cannot change flag");
482 break;
483 }
484#undef VXLAN_FLAG
485}
486
487#endif
488