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