1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2007-2014 Nicira, Inc.
4 */
5
6 #include <linux/uaccess.h>
7 #include <linux/netdevice.h>
8 #include <linux/etherdevice.h>
9 #include <linux/if_ether.h>
10 #include <linux/if_vlan.h>
11 #include <net/llc_pdu.h>
12 #include <linux/kernel.h>
13 #include <linux/jhash.h>
14 #include <linux/jiffies.h>
15 #include <linux/llc.h>
16 #include <linux/module.h>
17 #include <linux/in.h>
18 #include <linux/rcupdate.h>
19 #include <linux/cpumask.h>
20 #include <linux/if_arp.h>
21 #include <linux/ip.h>
22 #include <linux/ipv6.h>
23 #include <linux/mpls.h>
24 #include <linux/sctp.h>
25 #include <linux/smp.h>
26 #include <linux/tcp.h>
27 #include <linux/udp.h>
28 #include <linux/icmp.h>
29 #include <linux/icmpv6.h>
30 #include <linux/rculist.h>
31 #include <net/ip.h>
32 #include <net/ip_tunnels.h>
33 #include <net/ipv6.h>
34 #include <net/mpls.h>
35 #include <net/ndisc.h>
36 #include <net/nsh.h>
37 #include <net/pkt_cls.h>
38 #include <net/netfilter/nf_conntrack_zones.h>
39
40 #include "conntrack.h"
41 #include "datapath.h"
42 #include "flow.h"
43 #include "flow_netlink.h"
44 #include "vport.h"
45
46 u64 ovs_flow_used_time(unsigned long flow_jiffies)
47 {
48 struct timespec64 cur_ts;
49 u64 cur_ms, idle_ms;
50
51 ktime_get_ts64(&cur_ts);
52 idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
53 cur_ms = (u64)(u32)cur_ts.tv_sec * MSEC_PER_SEC +
54 cur_ts.tv_nsec / NSEC_PER_MSEC;
55
56 return cur_ms - idle_ms;
57 }
58
59 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
60
61 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
62 const struct sk_buff *skb)
63 {
64 struct sw_flow_stats *stats;
65 unsigned int cpu = smp_processor_id();
66 int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
67
68 stats = rcu_dereference(flow->stats[cpu]);
69
70 /* Check if already have CPU-specific stats. */
71 if (likely(stats)) {
72 spin_lock(&stats->lock);
73 /* Mark if we write on the pre-allocated stats. */
74 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
75 flow->stats_last_writer = cpu;
76 } else {
77 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
78 spin_lock(&stats->lock);
79
80 /* If the current CPU is the only writer on the
81 * pre-allocated stats keep using them.
82 */
83 if (unlikely(flow->stats_last_writer != cpu)) {
84 /* A previous locker may have already allocated the
85 * stats, so we need to check again. If CPU-specific
86 * stats were already allocated, we update the pre-
87 * allocated stats as we have already locked them.
88 */
89 if (likely(flow->stats_last_writer != -1) &&
90 likely(!rcu_access_pointer(flow->stats[cpu]))) {
91 /* Try to allocate CPU-specific stats. */
92 struct sw_flow_stats *new_stats;
93
94 new_stats =
95 kmem_cache_alloc_node(flow_stats_cache,
96 GFP_NOWAIT |
97 __GFP_THISNODE |
98 __GFP_NOWARN |
99 __GFP_NOMEMALLOC,
100 numa_node_id());
101 if (likely(new_stats)) {
102 new_stats->used = jiffies;
103 new_stats->packet_count = 1;
104 new_stats->byte_count = len;
105 new_stats->tcp_flags = tcp_flags;
106 spin_lock_init(&new_stats->lock);
107
108 rcu_assign_pointer(flow->stats[cpu],
109 new_stats);
110 cpumask_set_cpu(cpu,
111 flow->cpu_used_mask);
112 goto unlock;
113 }
114 }
115 flow->stats_last_writer = cpu;
116 }
117 }
118
119 stats->used = jiffies;
120 stats->packet_count++;
121 stats->byte_count += len;
122 stats->tcp_flags |= tcp_flags;
123 unlock:
124 spin_unlock(&stats->lock);
125 }
126
127 /* Must be called with rcu_read_lock or ovs_mutex. */
128 void ovs_flow_stats_get(const struct sw_flow *flow,
129 struct ovs_flow_stats *ovs_stats,
130 unsigned long *used, __be16 *tcp_flags)
131 {
132 int cpu;
133
134 *used = 0;
135 *tcp_flags = 0;
136 memset(ovs_stats, 0, sizeof(*ovs_stats));
137
138 /* We open code this to make sure cpu 0 is always considered */
139 for (cpu = 0; cpu < nr_cpu_ids;
140 cpu = cpumask_next(cpu, flow->cpu_used_mask)) {
141 struct sw_flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
142
143 if (stats) {
144 /* Local CPU may write on non-local stats, so we must
145 * block bottom-halves here.
146 */
147 spin_lock_bh(&stats->lock);
148 if (!*used || time_after(stats->used, *used))
149 *used = stats->used;
150 *tcp_flags |= stats->tcp_flags;
151 ovs_stats->n_packets += stats->packet_count;
152 ovs_stats->n_bytes += stats->byte_count;
153 spin_unlock_bh(&stats->lock);
154 }
155 }
156 }
157
158 /* Called with ovs_mutex. */
159 void ovs_flow_stats_clear(struct sw_flow *flow)
160 {
161 int cpu;
162
163 /* We open code this to make sure cpu 0 is always considered */
164 for (cpu = 0; cpu < nr_cpu_ids;
165 cpu = cpumask_next(cpu, flow->cpu_used_mask)) {
166 struct sw_flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
167
168 if (stats) {
169 spin_lock_bh(&stats->lock);
170 stats->used = 0;
171 stats->packet_count = 0;
172 stats->byte_count = 0;
173 stats->tcp_flags = 0;
174 spin_unlock_bh(&stats->lock);
175 }
176 }
177 }
178
179 static int check_header(struct sk_buff *skb, int len)
180 {
181 if (unlikely(skb->len < len))
182 return -EINVAL;
183 if (unlikely(!pskb_may_pull(skb, len)))
184 return -ENOMEM;
185 return 0;
186 }
187
188 static bool arphdr_ok(struct sk_buff *skb)
189 {
190 return pskb_may_pull(skb, skb_network_offset(skb) +
191 sizeof(struct arp_eth_header));
192 }
193
194 static int check_iphdr(struct sk_buff *skb)
195 {
196 unsigned int nh_ofs = skb_network_offset(skb);
197 unsigned int ip_len;
198 int err;
199
200 err = check_header(skb, nh_ofs + sizeof(struct iphdr));
201 if (unlikely(err))
202 return err;
203
204 ip_len = ip_hdrlen(skb);
205 if (unlikely(ip_len < sizeof(struct iphdr) ||
206 skb->len < nh_ofs + ip_len))
207 return -EINVAL;
208
209 skb_set_transport_header(skb, nh_ofs + ip_len);
210 return 0;
211 }
212
213 static bool tcphdr_ok(struct sk_buff *skb)
214 {
215 int th_ofs = skb_transport_offset(skb);
216 int tcp_len;
217
218 if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
219 return false;
220
221 tcp_len = tcp_hdrlen(skb);
222 if (unlikely(tcp_len < sizeof(struct tcphdr) ||
223 skb->len < th_ofs + tcp_len))
224 return false;
225
226 return true;
227 }
228
229 static bool udphdr_ok(struct sk_buff *skb)
230 {
231 return pskb_may_pull(skb, skb_transport_offset(skb) +
232 sizeof(struct udphdr));
233 }
234
235 static bool sctphdr_ok(struct sk_buff *skb)
236 {
237 return pskb_may_pull(skb, skb_transport_offset(skb) +
238 sizeof(struct sctphdr));
239 }
240
241 static bool icmphdr_ok(struct sk_buff *skb)
242 {
243 return pskb_may_pull(skb, skb_transport_offset(skb) +
244 sizeof(struct icmphdr));
245 }
246
247 /**
248 * get_ipv6_ext_hdrs() - Parses packet and sets IPv6 extension header flags.
249 *
250 * @skb: buffer where extension header data starts in packet
251 * @nh: ipv6 header
252 * @ext_hdrs: flags are stored here
253 *
254 * OFPIEH12_UNREP is set if more than one of a given IPv6 extension header
255 * is unexpectedly encountered. (Two destination options headers may be
256 * expected and would not cause this bit to be set.)
257 *
258 * OFPIEH12_UNSEQ is set if IPv6 extension headers were not in the order
259 * preferred (but not required) by RFC 2460:
260 *
261 * When more than one extension header is used in the same packet, it is
262 * recommended that those headers appear in the following order:
263 * IPv6 header
264 * Hop-by-Hop Options header
265 * Destination Options header
266 * Routing header
267 * Fragment header
268 * Authentication header
269 * Encapsulating Security Payload header
270 * Destination Options header
271 * upper-layer header
272 */
273 static void get_ipv6_ext_hdrs(struct sk_buff *skb, struct ipv6hdr *nh,
274 u16 *ext_hdrs)
275 {
276 u8 next_type = nh->nexthdr;
277 unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr);
278 int dest_options_header_count = 0;
279
280 *ext_hdrs = 0;
281
282 while (ipv6_ext_hdr(next_type)) {
283 struct ipv6_opt_hdr _hdr, *hp;
284
285 switch (next_type) {
286 case IPPROTO_NONE:
287 *ext_hdrs |= OFPIEH12_NONEXT;
288 /* stop parsing */
289 return;
290
291 case IPPROTO_ESP:
292 if (*ext_hdrs & OFPIEH12_ESP)
293 *ext_hdrs |= OFPIEH12_UNREP;
294 if ((*ext_hdrs & ~(OFPIEH12_HOP | OFPIEH12_DEST |
295 OFPIEH12_ROUTER | IPPROTO_FRAGMENT |
296 OFPIEH12_AUTH | OFPIEH12_UNREP)) ||
297 dest_options_header_count >= 2) {
298 *ext_hdrs |= OFPIEH12_UNSEQ;
299 }
300 *ext_hdrs |= OFPIEH12_ESP;
301 break;
302
303 case IPPROTO_AH:
304 if (*ext_hdrs & OFPIEH12_AUTH)
305 *ext_hdrs |= OFPIEH12_UNREP;
306 if ((*ext_hdrs &
307 ~(OFPIEH12_HOP | OFPIEH12_DEST | OFPIEH12_ROUTER |
308 IPPROTO_FRAGMENT | OFPIEH12_UNREP)) ||
309 dest_options_header_count >= 2) {
310 *ext_hdrs |= OFPIEH12_UNSEQ;
311 }
312 *ext_hdrs |= OFPIEH12_AUTH;
313 break;
314
315 case IPPROTO_DSTOPTS:
316 if (dest_options_header_count == 0) {
317 if (*ext_hdrs &
318 ~(OFPIEH12_HOP | OFPIEH12_UNREP))
319 *ext_hdrs |= OFPIEH12_UNSEQ;
320 *ext_hdrs |= OFPIEH12_DEST;
321 } else if (dest_options_header_count == 1) {
322 if (*ext_hdrs &
323 ~(OFPIEH12_HOP | OFPIEH12_DEST |
324 OFPIEH12_ROUTER | OFPIEH12_FRAG |
325 OFPIEH12_AUTH | OFPIEH12_ESP |
326 OFPIEH12_UNREP)) {
327 *ext_hdrs |= OFPIEH12_UNSEQ;
328 }
329 } else {
330 *ext_hdrs |= OFPIEH12_UNREP;
331 }
332 dest_options_header_count++;
333 break;
334
335 case IPPROTO_FRAGMENT:
336 if (*ext_hdrs & OFPIEH12_FRAG)
337 *ext_hdrs |= OFPIEH12_UNREP;
338 if ((*ext_hdrs & ~(OFPIEH12_HOP |
339 OFPIEH12_DEST |
340 OFPIEH12_ROUTER |
341 OFPIEH12_UNREP)) ||
342 dest_options_header_count >= 2) {
343 *ext_hdrs |= OFPIEH12_UNSEQ;
344 }
345 *ext_hdrs |= OFPIEH12_FRAG;
346 break;
347
348 case IPPROTO_ROUTING:
349 if (*ext_hdrs & OFPIEH12_ROUTER)
350 *ext_hdrs |= OFPIEH12_UNREP;
351 if ((*ext_hdrs & ~(OFPIEH12_HOP |
352 OFPIEH12_DEST |
353 OFPIEH12_UNREP)) ||
354 dest_options_header_count >= 2) {
355 *ext_hdrs |= OFPIEH12_UNSEQ;
356 }
357 *ext_hdrs |= OFPIEH12_ROUTER;
358 break;
359
360 case IPPROTO_HOPOPTS:
361 if (*ext_hdrs & OFPIEH12_HOP)
362 *ext_hdrs |= OFPIEH12_UNREP;
363 /* OFPIEH12_HOP is set to 1 if a hop-by-hop IPv6
364 * extension header is present as the first
365 * extension header in the packet.
366 */
367 if (*ext_hdrs == 0)
368 *ext_hdrs |= OFPIEH12_HOP;
369 else
370 *ext_hdrs |= OFPIEH12_UNSEQ;
371 break;
372
373 default:
374 return;
375 }
376
377 hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
378 if (!hp)
379 break;
380 next_type = hp->nexthdr;
381 start += ipv6_optlen(hp);
382 }
383 }
384
385 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
386 {
387 unsigned short frag_off;
388 unsigned int payload_ofs = 0;
389 unsigned int nh_ofs = skb_network_offset(skb);
390 unsigned int nh_len;
391 struct ipv6hdr *nh;
392 int err, nexthdr, flags = 0;
393
394 err = check_header(skb, nh_ofs + sizeof(*nh));
395 if (unlikely(err))
396 return err;
397
398 nh = ipv6_hdr(skb);
399
400 get_ipv6_ext_hdrs(skb, nh, &key->ipv6.exthdrs);
401
402 key->ip.proto = NEXTHDR_NONE;
403 key->ip.tos = ipv6_get_dsfield(nh);
404 key->ip.ttl = nh->hop_limit;
405 key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
406 key->ipv6.addr.src = nh->saddr;
407 key->ipv6.addr.dst = nh->daddr;
408
409 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
410 if (flags & IP6_FH_F_FRAG) {
411 if (frag_off) {
412 key->ip.frag = OVS_FRAG_TYPE_LATER;
413 key->ip.proto = NEXTHDR_FRAGMENT;
414 return 0;
415 }
416 key->ip.frag = OVS_FRAG_TYPE_FIRST;
417 } else {
418 key->ip.frag = OVS_FRAG_TYPE_NONE;
419 }
420
421 /* Delayed handling of error in ipv6_find_hdr() as it
422 * always sets flags and frag_off to a valid value which may be
423 * used to set key->ip.frag above.
424 */
425 if (unlikely(nexthdr < 0))
426 return -EPROTO;
427
428 nh_len = payload_ofs - nh_ofs;
429 skb_set_transport_header(skb, nh_ofs + nh_len);
430 key->ip.proto = nexthdr;
431 return nh_len;
432 }
433
434 static bool icmp6hdr_ok(struct sk_buff *skb)
435 {
436 return pskb_may_pull(skb, skb_transport_offset(skb) +
437 sizeof(struct icmp6hdr));
438 }
439
440 /**
441 * parse_vlan_tag - Parse vlan tag from vlan header.
442 * @skb: skb containing frame to parse
443 * @key_vh: pointer to parsed vlan tag
444 * @untag_vlan: should the vlan header be removed from the frame
445 *
446 * Return: ERROR on memory error.
447 * %0 if it encounters a non-vlan or incomplete packet.
448 * %1 after successfully parsing vlan tag.
449 */
450 static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
451 bool untag_vlan)
452 {
453 struct vlan_head *vh = (struct vlan_head *)skb->data;
454
455 if (likely(!eth_type_vlan(vh->tpid)))
456 return 0;
457
458 if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
459 return 0;
460
461 if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
462 sizeof(__be16))))
463 return -ENOMEM;
464
465 vh = (struct vlan_head *)skb->data;
466 key_vh->tci = vh->tci | htons(VLAN_CFI_MASK);
467 key_vh->tpid = vh->tpid;
468
469 if (unlikely(untag_vlan)) {
470 int offset = skb->data - skb_mac_header(skb);
471 u16 tci;
472 int err;
473
474 __skb_push(skb, offset);
475 err = __skb_vlan_pop(skb, &tci);
476 __skb_pull(skb, offset);
477 if (err)
478 return err;
479 __vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
480 } else {
481 __skb_pull(skb, sizeof(struct vlan_head));
482 }
483 return 1;
484 }
485
486 static void clear_vlan(struct sw_flow_key *key)
487 {
488 key->eth.vlan.tci = 0;
489 key->eth.vlan.tpid = 0;
490 key->eth.cvlan.tci = 0;
491 key->eth.cvlan.tpid = 0;
492 }
493
494 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
495 {
496 int res;
497
498 if (skb_vlan_tag_present(skb)) {
499 key->eth.vlan.tci = htons(skb->vlan_tci) | htons(VLAN_CFI_MASK);
500 key->eth.vlan.tpid = skb->vlan_proto;
501 } else {
502 /* Parse outer vlan tag in the non-accelerated case. */
503 res = parse_vlan_tag(skb, &key->eth.vlan, true);
504 if (res <= 0)
505 return res;
506 }
507
508 /* Parse inner vlan tag. */
509 res = parse_vlan_tag(skb, &key->eth.cvlan, false);
510 if (res <= 0)
511 return res;
512
513 return 0;
514 }
515
516 static __be16 parse_ethertype(struct sk_buff *skb)
517 {
518 struct llc_snap_hdr {
519 u8 dsap; /* Always 0xAA */
520 u8 ssap; /* Always 0xAA */
521 u8 ctrl;
522 u8 oui[3];
523 __be16 ethertype;
524 };
525 struct llc_snap_hdr *llc;
526 __be16 proto;
527
528 proto = *(__be16 *) skb->data;
529 __skb_pull(skb, sizeof(__be16));
530
531 if (eth_proto_is_802_3(proto))
532 return proto;
533
534 if (skb->len < sizeof(struct llc_snap_hdr))
535 return htons(ETH_P_802_2);
536
537 if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
538 return htons(0);
539
540 llc = (struct llc_snap_hdr *) skb->data;
541 if (llc->dsap != LLC_SAP_SNAP ||
542 llc->ssap != LLC_SAP_SNAP ||
543 (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
544 return htons(ETH_P_802_2);
545
546 __skb_pull(skb, sizeof(struct llc_snap_hdr));
547
548 if (eth_proto_is_802_3(llc->ethertype))
549 return llc->ethertype;
550
551 return htons(ETH_P_802_2);
552 }
553
554 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
555 int nh_len)
556 {
557 struct icmp6hdr *icmp = icmp6_hdr(skb);
558
559 /* The ICMPv6 type and code fields use the 16-bit transport port
560 * fields, so we need to store them in 16-bit network byte order.
561 */
562 key->tp.src = htons(icmp->icmp6_type);
563 key->tp.dst = htons(icmp->icmp6_code);
564
565 if (icmp->icmp6_code == 0 &&
566 (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
567 icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
568 int icmp_len = skb->len - skb_transport_offset(skb);
569 struct nd_msg *nd;
570 int offset;
571
572 memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
573
574 /* In order to process neighbor discovery options, we need the
575 * entire packet.
576 */
577 if (unlikely(icmp_len < sizeof(*nd)))
578 return 0;
579
580 if (unlikely(skb_linearize(skb)))
581 return -ENOMEM;
582
583 nd = (struct nd_msg *)skb_transport_header(skb);
584 key->ipv6.nd.target = nd->target;
585
586 icmp_len -= sizeof(*nd);
587 offset = 0;
588 while (icmp_len >= 8) {
589 struct nd_opt_hdr *nd_opt =
590 (struct nd_opt_hdr *)(nd->opt + offset);
591 int opt_len = nd_opt->nd_opt_len * 8;
592
593 if (unlikely(!opt_len || opt_len > icmp_len))
594 return 0;
595
596 /* Store the link layer address if the appropriate
597 * option is provided. It is considered an error if
598 * the same link layer option is specified twice.
599 */
600 if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
601 && opt_len == 8) {
602 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
603 goto invalid;
604 ether_addr_copy(key->ipv6.nd.sll,
605 &nd->opt[offset+sizeof(*nd_opt)]);
606 } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
607 && opt_len == 8) {
608 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
609 goto invalid;
610 ether_addr_copy(key->ipv6.nd.tll,
611 &nd->opt[offset+sizeof(*nd_opt)]);
612 }
613
614 icmp_len -= opt_len;
615 offset += opt_len;
616 }
617 }
618
619 return 0;
620
621 invalid:
622 memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
623 memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
624 memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
625
626 return 0;
627 }
628
629 static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
630 {
631 struct nshhdr *nh;
632 unsigned int nh_ofs = skb_network_offset(skb);
633 u8 version, length;
634 int err;
635
636 err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN);
637 if (unlikely(err))
638 return err;
639
640 nh = nsh_hdr(skb);
641 version = nsh_get_ver(nh);
642 length = nsh_hdr_len(nh);
643
644 if (version != 0)
645 return -EINVAL;
646
647 err = check_header(skb, nh_ofs + length);
648 if (unlikely(err))
649 return err;
650
651 nh = nsh_hdr(skb);
652 key->nsh.base.flags = nsh_get_flags(nh);
653 key->nsh.base.ttl = nsh_get_ttl(nh);
654 key->nsh.base.mdtype = nh->mdtype;
655 key->nsh.base.np = nh->np;
656 key->nsh.base.path_hdr = nh->path_hdr;
657 switch (key->nsh.base.mdtype) {
658 case NSH_M_TYPE1:
659 if (length != NSH_M_TYPE1_LEN)
660 return -EINVAL;
661 memcpy(key->nsh.context, nh->md1.context,
662 sizeof(nh->md1));
663 break;
664 case NSH_M_TYPE2:
665 memset(key->nsh.context, 0,
666 sizeof(nh->md1));
667 break;
668 default:
669 return -EINVAL;
670 }
671
672 return 0;
673 }
674
675 /**
676 * key_extract_l3l4 - extracts L3/L4 header information.
677 * @skb: sk_buff that contains the frame, with skb->data pointing to the
678 * L3 header
679 * @key: output flow key
680 *
681 * Return: %0 if successful, otherwise a negative errno value.
682 */
683 static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
684 {
685 int error;
686
687 /* Network layer. */
688 if (key->eth.type == htons(ETH_P_IP)) {
689 struct iphdr *nh;
690 __be16 offset;
691
692 error = check_iphdr(skb);
693 if (unlikely(error)) {
694 memset(&key->ip, 0, sizeof(key->ip));
695 memset(&key->ipv4, 0, sizeof(key->ipv4));
696 if (error == -EINVAL) {
697 skb->transport_header = skb->network_header;
698 error = 0;
699 }
700 return error;
701 }
702
703 nh = ip_hdr(skb);
704 key->ipv4.addr.src = nh->saddr;
705 key->ipv4.addr.dst = nh->daddr;
706
707 key->ip.proto = nh->protocol;
708 key->ip.tos = nh->tos;
709 key->ip.ttl = nh->ttl;
710
711 offset = nh->frag_off & htons(IP_OFFSET);
712 if (offset) {
713 key->ip.frag = OVS_FRAG_TYPE_LATER;
714 memset(&key->tp, 0, sizeof(key->tp));
715 return 0;
716 }
717 if (nh->frag_off & htons(IP_MF) ||
718 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
719 key->ip.frag = OVS_FRAG_TYPE_FIRST;
720 else
721 key->ip.frag = OVS_FRAG_TYPE_NONE;
722
723 /* Transport layer. */
724 if (key->ip.proto == IPPROTO_TCP) {
725 if (tcphdr_ok(skb)) {
726 struct tcphdr *tcp = tcp_hdr(skb);
727 key->tp.src = tcp->source;
728 key->tp.dst = tcp->dest;
729 key->tp.flags = TCP_FLAGS_BE16(tcp);
730 } else {
731 memset(&key->tp, 0, sizeof(key->tp));
732 }
733
734 } else if (key->ip.proto == IPPROTO_UDP) {
735 if (udphdr_ok(skb)) {
736 struct udphdr *udp = udp_hdr(skb);
737 key->tp.src = udp->source;
738 key->tp.dst = udp->dest;
739 } else {
740 memset(&key->tp, 0, sizeof(key->tp));
741 }
742 } else if (key->ip.proto == IPPROTO_SCTP) {
743 if (sctphdr_ok(skb)) {
744 struct sctphdr *sctp = sctp_hdr(skb);
745 key->tp.src = sctp->source;
746 key->tp.dst = sctp->dest;
747 } else {
748 memset(&key->tp, 0, sizeof(key->tp));
749 }
750 } else if (key->ip.proto == IPPROTO_ICMP) {
751 if (icmphdr_ok(skb)) {
752 struct icmphdr *icmp = icmp_hdr(skb);
753 /* The ICMP type and code fields use the 16-bit
754 * transport port fields, so we need to store
755 * them in 16-bit network byte order. */
756 key->tp.src = htons(icmp->type);
757 key->tp.dst = htons(icmp->code);
758 } else {
759 memset(&key->tp, 0, sizeof(key->tp));
760 }
761 }
762
763 } else if (key->eth.type == htons(ETH_P_ARP) ||
764 key->eth.type == htons(ETH_P_RARP)) {
765 struct arp_eth_header *arp;
766 bool arp_available = arphdr_ok(skb);
767
768 arp = (struct arp_eth_header *)skb_network_header(skb);
769
770 if (arp_available &&
771 arp->ar_hrd == htons(ARPHRD_ETHER) &&
772 arp->ar_pro == htons(ETH_P_IP) &&
773 arp->ar_hln == ETH_ALEN &&
774 arp->ar_pln == 4) {
775
776 /* We only match on the lower 8 bits of the opcode. */
777 if (ntohs(arp->ar_op) <= 0xff)
778 key->ip.proto = ntohs(arp->ar_op);
779 else
780 key->ip.proto = 0;
781
782 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
783 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
784 ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
785 ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
786 } else {
787 memset(&key->ip, 0, sizeof(key->ip));
788 memset(&key->ipv4, 0, sizeof(key->ipv4));
789 }
790 } else if (eth_p_mpls(key->eth.type)) {
791 u8 label_count = 1;
792
793 memset(&key->mpls, 0, sizeof(key->mpls));
794 skb_set_inner_network_header(skb, skb->mac_len);
795 while (1) {
796 __be32 lse;
797
798 error = check_header(skb, skb->mac_len +
799 label_count * MPLS_HLEN);
800 if (unlikely(error))
801 return 0;
802
803 memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
804
805 if (label_count <= MPLS_LABEL_DEPTH)
806 memcpy(&key->mpls.lse[label_count - 1], &lse,
807 MPLS_HLEN);
808
809 skb_set_inner_network_header(skb, skb->mac_len +
810 label_count * MPLS_HLEN);
811 if (lse & htonl(MPLS_LS_S_MASK))
812 break;
813
814 label_count++;
815 }
816 if (label_count > MPLS_LABEL_DEPTH)
817 label_count = MPLS_LABEL_DEPTH;
818
819 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0);
820 } else if (key->eth.type == htons(ETH_P_IPV6)) {
821 int nh_len; /* IPv6 Header + Extensions */
822
823 nh_len = parse_ipv6hdr(skb, key);
824 if (unlikely(nh_len < 0)) {
825 switch (nh_len) {
826 case -EINVAL:
827 memset(&key->ip, 0, sizeof(key->ip));
828 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
829 fallthrough;
830 case -EPROTO:
831 skb->transport_header = skb->network_header;
832 error = 0;
833 break;
834 default:
835 error = nh_len;
836 }
837 return error;
838 }
839
840 if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
841 memset(&key->tp, 0, sizeof(key->tp));
842 return 0;
843 }
844 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
845 key->ip.frag = OVS_FRAG_TYPE_FIRST;
846
847 /* Transport layer. */
848 if (key->ip.proto == NEXTHDR_TCP) {
849 if (tcphdr_ok(skb)) {
850 struct tcphdr *tcp = tcp_hdr(skb);
851 key->tp.src = tcp->source;
852 key->tp.dst = tcp->dest;
853 key->tp.flags = TCP_FLAGS_BE16(tcp);
854 } else {
855 memset(&key->tp, 0, sizeof(key->tp));
856 }
857 } else if (key->ip.proto == NEXTHDR_UDP) {
858 if (udphdr_ok(skb)) {
859 struct udphdr *udp = udp_hdr(skb);
860 key->tp.src = udp->source;
861 key->tp.dst = udp->dest;
862 } else {
863 memset(&key->tp, 0, sizeof(key->tp));
864 }
865 } else if (key->ip.proto == NEXTHDR_SCTP) {
866 if (sctphdr_ok(skb)) {
867 struct sctphdr *sctp = sctp_hdr(skb);
868 key->tp.src = sctp->source;
869 key->tp.dst = sctp->dest;
870 } else {
871 memset(&key->tp, 0, sizeof(key->tp));
872 }
873 } else if (key->ip.proto == NEXTHDR_ICMP) {
874 if (icmp6hdr_ok(skb)) {
875 error = parse_icmpv6(skb, key, nh_len);
876 if (error)
877 return error;
878 } else {
879 memset(&key->tp, 0, sizeof(key->tp));
880 }
881 }
882 } else if (key->eth.type == htons(ETH_P_NSH)) {
883 error = parse_nsh(skb, key);
884 if (error)
885 return error;
886 }
887 return 0;
888 }
889
890 /**
891 * key_extract - extracts a flow key from an Ethernet frame.
892 * @skb: sk_buff that contains the frame, with skb->data pointing to the
893 * Ethernet header
894 * @key: output flow key
895 *
896 * The caller must ensure that skb->len >= ETH_HLEN.
897 *
898 * Initializes @skb header fields as follows:
899 *
900 * - skb->mac_header: the L2 header.
901 *
902 * - skb->network_header: just past the L2 header, or just past the
903 * VLAN header, to the first byte of the L2 payload.
904 *
905 * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
906 * on output, then just past the IP header, if one is present and
907 * of a correct length, otherwise the same as skb->network_header.
908 * For other key->eth.type values it is left untouched.
909 *
910 * - skb->protocol: the type of the data starting at skb->network_header.
911 * Equals to key->eth.type.
912 *
913 * Return: %0 if successful, otherwise a negative errno value.
914 */
915 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
916 {
917 struct ethhdr *eth;
918
919 /* Flags are always used as part of stats */
920 key->tp.flags = 0;
921
922 skb_reset_mac_header(skb);
923
924 /* Link layer. */
925 clear_vlan(key);
926 if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
927 if (unlikely(eth_type_vlan(skb->protocol)))
928 return -EINVAL;
929
930 skb_reset_network_header(skb);
931 key->eth.type = skb->protocol;
932 } else {
933 eth = eth_hdr(skb);
934 ether_addr_copy(key->eth.src, eth->h_source);
935 ether_addr_copy(key->eth.dst, eth->h_dest);
936
937 __skb_pull(skb, 2 * ETH_ALEN);
938 /* We are going to push all headers that we pull, so no need to
939 * update skb->csum here.
940 */
941
942 if (unlikely(parse_vlan(skb, key)))
943 return -ENOMEM;
944
945 key->eth.type = parse_ethertype(skb);
946 if (unlikely(key->eth.type == htons(0)))
947 return -ENOMEM;
948
949 /* Multiple tagged packets need to retain TPID to satisfy
950 * skb_vlan_pop(), which will later shift the ethertype into
951 * skb->protocol.
952 */
953 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
954 skb->protocol = key->eth.cvlan.tpid;
955 else
956 skb->protocol = key->eth.type;
957
958 skb_reset_network_header(skb);
959 __skb_push(skb, skb->data - skb_mac_header(skb));
960 }
961
962 skb_reset_mac_len(skb);
963
964 /* Fill out L3/L4 key info, if any */
965 return key_extract_l3l4(skb, key);
966 }
967
968 /* In the case of conntrack fragment handling it expects L3 headers,
969 * add a helper.
970 */
971 int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
972 {
973 return key_extract_l3l4(skb, key);
974 }
975
976 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
977 {
978 int res;
979
980 res = key_extract(skb, key);
981 if (!res)
982 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
983
984 return res;
985 }
986
987 static int key_extract_mac_proto(struct sk_buff *skb)
988 {
989 switch (skb->dev->type) {
990 case ARPHRD_ETHER:
991 return MAC_PROTO_ETHERNET;
992 case ARPHRD_NONE:
993 if (skb->protocol == htons(ETH_P_TEB))
994 return MAC_PROTO_ETHERNET;
995 return MAC_PROTO_NONE;
996 }
997 WARN_ON_ONCE(1);
998 return -EINVAL;
999 }
1000
1001 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
1002 struct sk_buff *skb, struct sw_flow_key *key)
1003 {
1004 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1005 struct tc_skb_ext *tc_ext;
1006 #endif
1007 bool post_ct = false, post_ct_snat = false, post_ct_dnat = false;
1008 int res, err;
1009 u16 zone = 0;
1010
1011 /* Extract metadata from packet. */
1012 if (tun_info) {
1013 key->tun_proto = ip_tunnel_info_af(tun_info);
1014 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
1015
1016 if (tun_info->options_len) {
1017 BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
1018 8)) - 1
1019 > sizeof(key->tun_opts));
1020
1021 ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
1022 tun_info);
1023 key->tun_opts_len = tun_info->options_len;
1024 } else {
1025 key->tun_opts_len = 0;
1026 }
1027 } else {
1028 key->tun_proto = 0;
1029 key->tun_opts_len = 0;
1030 memset(&key->tun_key, 0, sizeof(key->tun_key));
1031 }
1032
1033 key->phy.priority = skb->priority;
1034 key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
1035 key->phy.skb_mark = skb->mark;
1036 key->ovs_flow_hash = 0;
1037 res = key_extract_mac_proto(skb);
1038 if (res < 0)
1039 return res;
1040 key->mac_proto = res;
1041
1042 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1043 if (tc_skb_ext_tc_enabled()) {
1044 tc_ext = skb_ext_find(skb, TC_SKB_EXT);
1045 key->recirc_id = tc_ext && !tc_ext->act_miss ?
1046 tc_ext->chain : 0;
1047 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0;
1048 post_ct = tc_ext ? tc_ext->post_ct : false;
1049 post_ct_snat = post_ct ? tc_ext->post_ct_snat : false;
1050 post_ct_dnat = post_ct ? tc_ext->post_ct_dnat : false;
1051 zone = post_ct ? tc_ext->zone : 0;
1052 } else {
1053 key->recirc_id = 0;
1054 }
1055 #else
1056 key->recirc_id = 0;
1057 #endif
1058
1059 err = key_extract(skb, key);
1060 if (!err) {
1061 ovs_ct_fill_key(skb, key, post_ct); /* Must be after key_extract(). */
1062 if (post_ct) {
1063 if (!skb_get_nfct(skb)) {
1064 key->ct_zone = zone;
1065 } else {
1066 if (!post_ct_dnat)
1067 key->ct_state &= ~OVS_CS_F_DST_NAT;
1068 if (!post_ct_snat)
1069 key->ct_state &= ~OVS_CS_F_SRC_NAT;
1070 }
1071 }
1072 }
1073 return err;
1074 }
1075
1076 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
1077 struct sk_buff *skb,
1078 struct sw_flow_key *key, bool log)
1079 {
1080 const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
1081 u64 attrs = 0;
1082 int err;
1083
1084 err = parse_flow_nlattrs(attr, a, &attrs, log);
1085 if (err)
1086 return -EINVAL;
1087
1088 /* Extract metadata from netlink attributes. */
1089 err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
1090 if (err)
1091 return err;
1092
1093 /* key_extract assumes that skb->protocol is set-up for
1094 * layer 3 packets which is the case for other callers,
1095 * in particular packets received from the network stack.
1096 * Here the correct value can be set from the metadata
1097 * extracted above.
1098 * For L2 packet key eth type would be zero. skb protocol
1099 * would be set to correct value later during key-extact.
1100 */
1101
1102 skb->protocol = key->eth.type;
1103 err = key_extract(skb, key);
1104 if (err)
1105 return err;
1106
1107 /* Check that we have conntrack original direction tuple metadata only
1108 * for packets for which it makes sense. Otherwise the key may be
1109 * corrupted due to overlapping key fields.
1110 */
1111 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
1112 key->eth.type != htons(ETH_P_IP))
1113 return -EINVAL;
1114 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
1115 (key->eth.type != htons(ETH_P_IPV6) ||
1116 sw_flow_key_is_nd(key)))
1117 return -EINVAL;
1118
1119 return 0;
1120 }
1121
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