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