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 #include <net/nexthop.h>
11
12 #define IANA_VXLAN_UDP_PORT 4789
13
14 /* VXLAN protocol (RFC 7348) header:
15 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
16 * |R|R|R|R|I|R|R|R| Reserved |
17 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
18 * | VXLAN Network Identifier (VNI) | Reserved |
19 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
20 *
21 * I = VXLAN Network Identifier (VNI) present.
22 */
23 struct vxlanhdr {
24 __be32 vx_flags;
25 __be32 vx_vni;
26 };
27
28 /* VXLAN header flags. */
29 #define VXLAN_HF_VNI cpu_to_be32(BIT(27))
30
31 #define VXLAN_N_VID (1u << 24)
32 #define VXLAN_VID_MASK (VXLAN_N_VID - 1)
33 #define VXLAN_VNI_MASK cpu_to_be32(VXLAN_VID_MASK << 8)
34 #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
35
36 #define VNI_HASH_BITS 10
37 #define VNI_HASH_SIZE (1<<VNI_HASH_BITS)
38 #define FDB_HASH_BITS 8
39 #define FDB_HASH_SIZE (1<<FDB_HASH_BITS)
40
41 /* Remote checksum offload for VXLAN (VXLAN_F_REMCSUM_[RT]X):
42 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43 * |R|R|R|R|I|R|R|R|R|R|C| Reserved |
44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 * | VXLAN Network Identifier (VNI) |O| Csum start |
46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 *
48 * C = Remote checksum offload bit. When set indicates that the
49 * remote checksum offload data is present.
50 *
51 * O = Offset bit. Indicates the checksum offset relative to
52 * checksum start.
53 *
54 * Csum start = Checksum start divided by two.
55 *
56 * http://tools.ietf.org/html/draft-herbert-vxlan-rco
57 */
58
59 /* VXLAN-RCO header flags. */
60 #define VXLAN_HF_RCO cpu_to_be32(BIT(21))
61
62 /* Remote checksum offload header option */
63 #define VXLAN_RCO_MASK cpu_to_be32(0x7f) /* Last byte of vni field */
64 #define VXLAN_RCO_UDP cpu_to_be32(0x80) /* Indicate UDP RCO (TCP when not set *) */
65 #define VXLAN_RCO_SHIFT 1 /* Left shift of start */
66 #define VXLAN_RCO_SHIFT_MASK ((1 << VXLAN_RCO_SHIFT) - 1)
67 #define VXLAN_MAX_REMCSUM_START (0x7f << VXLAN_RCO_SHIFT)
68
69 /*
70 * VXLAN Group Based Policy Extension (VXLAN_F_GBP):
71 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72 * |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID |
73 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
74 * | VXLAN Network Identifier (VNI) | Reserved |
75 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
76 *
77 * G = Group Policy ID present.
78 *
79 * D = Don't Learn bit. When set, this bit indicates that the egress
80 * VTEP MUST NOT learn the source address of the encapsulated frame.
81 *
82 * A = Indicates that the group policy has already been applied to
83 * this packet. Policies MUST NOT be applied by devices when the
84 * A bit is set.
85 *
86 * https://tools.ietf.org/html/draft-smith-vxlan-group-policy
87 */
88 struct vxlanhdr_gbp {
89 u8 vx_flags;
90 #ifdef __LITTLE_ENDIAN_BITFIELD
91 u8 reserved_flags1:3,
92 policy_applied:1,
93 reserved_flags2:2,
94 dont_learn:1,
95 reserved_flags3:1;
96 #elif defined(__BIG_ENDIAN_BITFIELD)
97 u8 reserved_flags1:1,
98 dont_learn:1,
99 reserved_flags2:2,
100 policy_applied:1,
101 reserved_flags3:3;
102 #else
103 #error "Please fix <asm/byteorder.h>"
104 #endif
105 __be16 policy_id;
106 __be32 vx_vni;
107 };
108
109 /* VXLAN-GBP header flags. */
110 #define VXLAN_HF_GBP cpu_to_be32(BIT(31))
111
112 #define VXLAN_GBP_USED_BITS (VXLAN_HF_GBP | cpu_to_be32(0xFFFFFF))
113
114 /* skb->mark mapping
115 *
116 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
117 * |R|R|R|R|R|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID |
118 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
119 */
120 #define VXLAN_GBP_DONT_LEARN (BIT(6) << 16)
121 #define VXLAN_GBP_POLICY_APPLIED (BIT(3) << 16)
122 #define VXLAN_GBP_ID_MASK (0xFFFF)
123
124 #define VXLAN_GBP_MASK (VXLAN_GBP_DONT_LEARN | VXLAN_GBP_POLICY_APPLIED | \
125 VXLAN_GBP_ID_MASK)
126
127 /*
128 * VXLAN Generic Protocol Extension (VXLAN_F_GPE):
129 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
130 * |R|R|Ver|I|P|R|O| Reserved |Next Protocol |
131 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
132 * | VXLAN Network Identifier (VNI) | Reserved |
133 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
134 *
135 * Ver = Version. Indicates VXLAN GPE protocol version.
136 *
137 * P = Next Protocol Bit. The P bit is set to indicate that the
138 * Next Protocol field is present.
139 *
140 * O = OAM Flag Bit. The O bit is set to indicate that the packet
141 * is an OAM packet.
142 *
143 * Next Protocol = This 8 bit field indicates the protocol header
144 * immediately following the VXLAN GPE header.
145 *
146 * https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-01
147 */
148
149 struct vxlanhdr_gpe {
150 #if defined(__LITTLE_ENDIAN_BITFIELD)
151 u8 oam_flag:1,
152 reserved_flags1:1,
153 np_applied:1,
154 instance_applied:1,
155 version:2,
156 reserved_flags2:2;
157 #elif defined(__BIG_ENDIAN_BITFIELD)
158 u8 reserved_flags2:2,
159 version:2,
160 instance_applied:1,
161 np_applied:1,
162 reserved_flags1:1,
163 oam_flag:1;
164 #endif
165 u8 reserved_flags3;
166 u8 reserved_flags4;
167 u8 next_protocol;
168 __be32 vx_vni;
169 };
170
171 /* VXLAN-GPE header flags. */
172 #define VXLAN_HF_VER cpu_to_be32(BIT(29) | BIT(28))
173 #define VXLAN_HF_NP cpu_to_be32(BIT(26))
174 #define VXLAN_HF_OAM cpu_to_be32(BIT(24))
175
176 #define VXLAN_GPE_USED_BITS (VXLAN_HF_VER | VXLAN_HF_NP | VXLAN_HF_OAM | \
177 cpu_to_be32(0xff))
178
179 struct vxlan_metadata {
180 u32 gbp;
181 };
182
183 /* per UDP socket information */
184 struct vxlan_sock {
185 struct hlist_node hlist;
186 struct socket *sock;
187 struct hlist_head vni_list[VNI_HASH_SIZE];
188 refcount_t refcnt;
189 u32 flags;
190 };
191
192 union vxlan_addr {
193 struct sockaddr_in sin;
194 struct sockaddr_in6 sin6;
195 struct sockaddr sa;
196 };
197
198 struct vxlan_rdst {
199 union vxlan_addr remote_ip;
200 __be16 remote_port;
201 u8 offloaded:1;
202 __be32 remote_vni;
203 u32 remote_ifindex;
204 struct net_device *remote_dev;
205 struct list_head list;
206 struct rcu_head rcu;
207 struct dst_cache dst_cache;
208 };
209
210 struct vxlan_config {
211 union vxlan_addr remote_ip;
212 union vxlan_addr saddr;
213 __be32 vni;
214 int remote_ifindex;
215 int mtu;
216 __be16 dst_port;
217 u16 port_min;
218 u16 port_max;
219 u8 tos;
220 u8 ttl;
221 __be32 label;
222 u32 flags;
223 unsigned long age_interval;
224 unsigned int addrmax;
225 bool no_share;
226 enum ifla_vxlan_df df;
227 };
228
229 struct vxlan_dev_node {
230 struct hlist_node hlist;
231 struct vxlan_dev *vxlan;
232 };
233
234 /* Pseudo network device */
235 struct vxlan_dev {
236 struct vxlan_dev_node hlist4; /* vni hash table for IPv4 socket */
237 #if IS_ENABLED(CONFIG_IPV6)
238 struct vxlan_dev_node hlist6; /* vni hash table for IPv6 socket */
239 #endif
240 struct list_head next; /* vxlan's per namespace list */
241 struct vxlan_sock __rcu *vn4_sock; /* listening socket for IPv4 */
242 #if IS_ENABLED(CONFIG_IPV6)
243 struct vxlan_sock __rcu *vn6_sock; /* listening socket for IPv6 */
244 #endif
245 struct net_device *dev;
246 struct net *net; /* netns for packet i/o */
247 struct vxlan_rdst default_dst; /* default destination */
248
249 struct timer_list age_timer;
250 spinlock_t hash_lock[FDB_HASH_SIZE];
251 unsigned int addrcnt;
252 struct gro_cells gro_cells;
253
254 struct vxlan_config cfg;
255
256 struct hlist_head fdb_head[FDB_HASH_SIZE];
257 };
258
259 #define VXLAN_F_LEARN 0x01
260 #define VXLAN_F_PROXY 0x02
261 #define VXLAN_F_RSC 0x04
262 #define VXLAN_F_L2MISS 0x08
263 #define VXLAN_F_L3MISS 0x10
264 #define VXLAN_F_IPV6 0x20
265 #define VXLAN_F_UDP_ZERO_CSUM_TX 0x40
266 #define VXLAN_F_UDP_ZERO_CSUM6_TX 0x80
267 #define VXLAN_F_UDP_ZERO_CSUM6_RX 0x100
268 #define VXLAN_F_REMCSUM_TX 0x200
269 #define VXLAN_F_REMCSUM_RX 0x400
270 #define VXLAN_F_GBP 0x800
271 #define VXLAN_F_REMCSUM_NOPARTIAL 0x1000
272 #define VXLAN_F_COLLECT_METADATA 0x2000
273 #define VXLAN_F_GPE 0x4000
274 #define VXLAN_F_IPV6_LINKLOCAL 0x8000
275 #define VXLAN_F_TTL_INHERIT 0x10000
276
277 /* Flags that are used in the receive path. These flags must match in
278 * order for a socket to be shareable
279 */
280 #define VXLAN_F_RCV_FLAGS (VXLAN_F_GBP | \
281 VXLAN_F_GPE | \
282 VXLAN_F_UDP_ZERO_CSUM6_RX | \
283 VXLAN_F_REMCSUM_RX | \
284 VXLAN_F_REMCSUM_NOPARTIAL | \
285 VXLAN_F_COLLECT_METADATA)
286
287 /* Flags that can be set together with VXLAN_F_GPE. */
288 #define VXLAN_F_ALLOWED_GPE (VXLAN_F_GPE | \
289 VXLAN_F_IPV6 | \
290 VXLAN_F_IPV6_LINKLOCAL | \
291 VXLAN_F_UDP_ZERO_CSUM_TX | \
292 VXLAN_F_UDP_ZERO_CSUM6_TX | \
293 VXLAN_F_UDP_ZERO_CSUM6_RX | \
294 VXLAN_F_COLLECT_METADATA)
295
296 struct net_device *vxlan_dev_create(struct net *net, const char *name,
297 u8 name_assign_type, struct vxlan_config *conf);
298
vxlan_features_check(struct sk_buff * skb,netdev_features_t features)299 static inline netdev_features_t vxlan_features_check(struct sk_buff *skb,
300 netdev_features_t features)
301 {
302 u8 l4_hdr = 0;
303
304 if (!skb->encapsulation)
305 return features;
306
307 switch (vlan_get_protocol(skb)) {
308 case htons(ETH_P_IP):
309 l4_hdr = ip_hdr(skb)->protocol;
310 break;
311 case htons(ETH_P_IPV6):
312 l4_hdr = ipv6_hdr(skb)->nexthdr;
313 break;
314 default:
315 return features;
316 }
317
318 if ((l4_hdr == IPPROTO_UDP) &&
319 (skb->inner_protocol_type != ENCAP_TYPE_ETHER ||
320 skb->inner_protocol != htons(ETH_P_TEB) ||
321 (skb_inner_mac_header(skb) - skb_transport_header(skb) !=
322 sizeof(struct udphdr) + sizeof(struct vxlanhdr)) ||
323 (skb->ip_summed != CHECKSUM_NONE &&
324 !can_checksum_protocol(features, inner_eth_hdr(skb)->h_proto))))
325 return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
326
327 return features;
328 }
329
330 /* IP header + UDP + VXLAN + Ethernet header */
331 #define VXLAN_HEADROOM (20 + 8 + 8 + 14)
332 /* IPv6 header + UDP + VXLAN + Ethernet header */
333 #define VXLAN6_HEADROOM (40 + 8 + 8 + 14)
334
vxlan_hdr(struct sk_buff * skb)335 static inline struct vxlanhdr *vxlan_hdr(struct sk_buff *skb)
336 {
337 return (struct vxlanhdr *)(udp_hdr(skb) + 1);
338 }
339
vxlan_vni(__be32 vni_field)340 static inline __be32 vxlan_vni(__be32 vni_field)
341 {
342 #if defined(__BIG_ENDIAN)
343 return (__force __be32)((__force u32)vni_field >> 8);
344 #else
345 return (__force __be32)((__force u32)(vni_field & VXLAN_VNI_MASK) << 8);
346 #endif
347 }
348
vxlan_vni_field(__be32 vni)349 static inline __be32 vxlan_vni_field(__be32 vni)
350 {
351 #if defined(__BIG_ENDIAN)
352 return (__force __be32)((__force u32)vni << 8);
353 #else
354 return (__force __be32)((__force u32)vni >> 8);
355 #endif
356 }
357
vxlan_rco_start(__be32 vni_field)358 static inline size_t vxlan_rco_start(__be32 vni_field)
359 {
360 return be32_to_cpu(vni_field & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;
361 }
362
vxlan_rco_offset(__be32 vni_field)363 static inline size_t vxlan_rco_offset(__be32 vni_field)
364 {
365 return (vni_field & VXLAN_RCO_UDP) ?
366 offsetof(struct udphdr, check) :
367 offsetof(struct tcphdr, check);
368 }
369
vxlan_compute_rco(unsigned int start,unsigned int offset)370 static inline __be32 vxlan_compute_rco(unsigned int start, unsigned int offset)
371 {
372 __be32 vni_field = cpu_to_be32(start >> VXLAN_RCO_SHIFT);
373
374 if (offset == offsetof(struct udphdr, check))
375 vni_field |= VXLAN_RCO_UDP;
376 return vni_field;
377 }
378
vxlan_get_sk_family(struct vxlan_sock * vs)379 static inline unsigned short vxlan_get_sk_family(struct vxlan_sock *vs)
380 {
381 return vs->sock->sk->sk_family;
382 }
383
384 #if IS_ENABLED(CONFIG_IPV6)
385
vxlan_addr_any(const union vxlan_addr * ipa)386 static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
387 {
388 if (ipa->sa.sa_family == AF_INET6)
389 return ipv6_addr_any(&ipa->sin6.sin6_addr);
390 else
391 return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
392 }
393
vxlan_addr_multicast(const union vxlan_addr * ipa)394 static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
395 {
396 if (ipa->sa.sa_family == AF_INET6)
397 return ipv6_addr_is_multicast(&ipa->sin6.sin6_addr);
398 else
399 return ipv4_is_multicast(ipa->sin.sin_addr.s_addr);
400 }
401
402 #else /* !IS_ENABLED(CONFIG_IPV6) */
403
vxlan_addr_any(const union vxlan_addr * ipa)404 static inline bool vxlan_addr_any(const union vxlan_addr *ipa)
405 {
406 return ipa->sin.sin_addr.s_addr == htonl(INADDR_ANY);
407 }
408
vxlan_addr_multicast(const union vxlan_addr * ipa)409 static inline bool vxlan_addr_multicast(const union vxlan_addr *ipa)
410 {
411 return ipv4_is_multicast(ipa->sin.sin_addr.s_addr);
412 }
413
414 #endif /* IS_ENABLED(CONFIG_IPV6) */
415
netif_is_vxlan(const struct net_device * dev)416 static inline bool netif_is_vxlan(const struct net_device *dev)
417 {
418 return dev->rtnl_link_ops &&
419 !strcmp(dev->rtnl_link_ops->kind, "vxlan");
420 }
421
422 struct switchdev_notifier_vxlan_fdb_info {
423 struct switchdev_notifier_info info; /* must be first */
424 union vxlan_addr remote_ip;
425 __be16 remote_port;
426 __be32 remote_vni;
427 u32 remote_ifindex;
428 u8 eth_addr[ETH_ALEN];
429 __be32 vni;
430 bool offloaded;
431 bool added_by_user;
432 };
433
434 #if IS_ENABLED(CONFIG_VXLAN)
435 int vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
436 struct switchdev_notifier_vxlan_fdb_info *fdb_info);
437 int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
438 struct notifier_block *nb,
439 struct netlink_ext_ack *extack);
440 void vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni);
441
442 #else
443 static inline int
vxlan_fdb_find_uc(struct net_device * dev,const u8 * mac,__be32 vni,struct switchdev_notifier_vxlan_fdb_info * fdb_info)444 vxlan_fdb_find_uc(struct net_device *dev, const u8 *mac, __be32 vni,
445 struct switchdev_notifier_vxlan_fdb_info *fdb_info)
446 {
447 return -ENOENT;
448 }
449
vxlan_fdb_replay(const struct net_device * dev,__be32 vni,struct notifier_block * nb,struct netlink_ext_ack * extack)450 static inline int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
451 struct notifier_block *nb,
452 struct netlink_ext_ack *extack)
453 {
454 return -EOPNOTSUPP;
455 }
456
457 static inline void
vxlan_fdb_clear_offload(const struct net_device * dev,__be32 vni)458 vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni)
459 {
460 }
461 #endif
462
vxlan_flag_attr_error(int attrtype,struct netlink_ext_ack * extack)463 static inline void vxlan_flag_attr_error(int attrtype,
464 struct netlink_ext_ack *extack)
465 {
466 #define VXLAN_FLAG(flg) \
467 case IFLA_VXLAN_##flg: \
468 NL_SET_ERR_MSG_MOD(extack, \
469 "cannot change " #flg " flag"); \
470 break
471 switch (attrtype) {
472 VXLAN_FLAG(TTL_INHERIT);
473 VXLAN_FLAG(LEARNING);
474 VXLAN_FLAG(PROXY);
475 VXLAN_FLAG(RSC);
476 VXLAN_FLAG(L2MISS);
477 VXLAN_FLAG(L3MISS);
478 VXLAN_FLAG(COLLECT_METADATA);
479 VXLAN_FLAG(UDP_ZERO_CSUM6_TX);
480 VXLAN_FLAG(UDP_ZERO_CSUM6_RX);
481 VXLAN_FLAG(REMCSUM_TX);
482 VXLAN_FLAG(REMCSUM_RX);
483 VXLAN_FLAG(GBP);
484 VXLAN_FLAG(GPE);
485 VXLAN_FLAG(REMCSUM_NOPARTIAL);
486 default:
487 NL_SET_ERR_MSG_MOD(extack, \
488 "cannot change flag");
489 break;
490 }
491 #undef VXLAN_FLAG
492 }
493
vxlan_fdb_nh_path_select(struct nexthop * nh,int hash,struct vxlan_rdst * rdst)494 static inline bool vxlan_fdb_nh_path_select(struct nexthop *nh,
495 int hash,
496 struct vxlan_rdst *rdst)
497 {
498 struct fib_nh_common *nhc;
499
500 nhc = nexthop_path_fdb_result(nh, hash);
501 if (unlikely(!nhc))
502 return false;
503
504 switch (nhc->nhc_gw_family) {
505 case AF_INET:
506 rdst->remote_ip.sin.sin_addr.s_addr = nhc->nhc_gw.ipv4;
507 rdst->remote_ip.sa.sa_family = AF_INET;
508 break;
509 case AF_INET6:
510 rdst->remote_ip.sin6.sin6_addr = nhc->nhc_gw.ipv6;
511 rdst->remote_ip.sa.sa_family = AF_INET6;
512 break;
513 }
514
515 return true;
516 }
517
518 #endif
519
