Loading...
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
38#include "conntrack.h"
39#include "datapath.h"
40#include "flow.h"
41#include "flow_netlink.h"
42#include "vport.h"
43
44u64 ovs_flow_used_time(unsigned long flow_jiffies)
45{
46 struct timespec64 cur_ts;
47 u64 cur_ms, idle_ms;
48
49 ktime_get_ts64(&cur_ts);
50 idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
51 cur_ms = (u64)(u32)cur_ts.tv_sec * MSEC_PER_SEC +
52 cur_ts.tv_nsec / NSEC_PER_MSEC;
53
54 return cur_ms - idle_ms;
55}
56
57#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
58
59void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
60 const struct sk_buff *skb)
61{
62 struct sw_flow_stats *stats;
63 unsigned int cpu = smp_processor_id();
64 int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
65
66 stats = rcu_dereference(flow->stats[cpu]);
67
68 /* Check if already have CPU-specific stats. */
69 if (likely(stats)) {
70 spin_lock(&stats->lock);
71 /* Mark if we write on the pre-allocated stats. */
72 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
73 flow->stats_last_writer = cpu;
74 } else {
75 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
76 spin_lock(&stats->lock);
77
78 /* If the current CPU is the only writer on the
79 * pre-allocated stats keep using them.
80 */
81 if (unlikely(flow->stats_last_writer != cpu)) {
82 /* A previous locker may have already allocated the
83 * stats, so we need to check again. If CPU-specific
84 * stats were already allocated, we update the pre-
85 * allocated stats as we have already locked them.
86 */
87 if (likely(flow->stats_last_writer != -1) &&
88 likely(!rcu_access_pointer(flow->stats[cpu]))) {
89 /* Try to allocate CPU-specific stats. */
90 struct sw_flow_stats *new_stats;
91
92 new_stats =
93 kmem_cache_alloc_node(flow_stats_cache,
94 GFP_NOWAIT |
95 __GFP_THISNODE |
96 __GFP_NOWARN |
97 __GFP_NOMEMALLOC,
98 numa_node_id());
99 if (likely(new_stats)) {
100 new_stats->used = jiffies;
101 new_stats->packet_count = 1;
102 new_stats->byte_count = len;
103 new_stats->tcp_flags = tcp_flags;
104 spin_lock_init(&new_stats->lock);
105
106 rcu_assign_pointer(flow->stats[cpu],
107 new_stats);
108 cpumask_set_cpu(cpu, &flow->cpu_used_mask);
109 goto unlock;
110 }
111 }
112 flow->stats_last_writer = cpu;
113 }
114 }
115
116 stats->used = jiffies;
117 stats->packet_count++;
118 stats->byte_count += len;
119 stats->tcp_flags |= tcp_flags;
120unlock:
121 spin_unlock(&stats->lock);
122}
123
124/* Must be called with rcu_read_lock or ovs_mutex. */
125void ovs_flow_stats_get(const struct sw_flow *flow,
126 struct ovs_flow_stats *ovs_stats,
127 unsigned long *used, __be16 *tcp_flags)
128{
129 int cpu;
130
131 *used = 0;
132 *tcp_flags = 0;
133 memset(ovs_stats, 0, sizeof(*ovs_stats));
134
135 /* We open code this to make sure cpu 0 is always considered */
136 for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
137 struct sw_flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
138
139 if (stats) {
140 /* Local CPU may write on non-local stats, so we must
141 * block bottom-halves here.
142 */
143 spin_lock_bh(&stats->lock);
144 if (!*used || time_after(stats->used, *used))
145 *used = stats->used;
146 *tcp_flags |= stats->tcp_flags;
147 ovs_stats->n_packets += stats->packet_count;
148 ovs_stats->n_bytes += stats->byte_count;
149 spin_unlock_bh(&stats->lock);
150 }
151 }
152}
153
154/* Called with ovs_mutex. */
155void ovs_flow_stats_clear(struct sw_flow *flow)
156{
157 int cpu;
158
159 /* We open code this to make sure cpu 0 is always considered */
160 for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
161 struct sw_flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
162
163 if (stats) {
164 spin_lock_bh(&stats->lock);
165 stats->used = 0;
166 stats->packet_count = 0;
167 stats->byte_count = 0;
168 stats->tcp_flags = 0;
169 spin_unlock_bh(&stats->lock);
170 }
171 }
172}
173
174static int check_header(struct sk_buff *skb, int len)
175{
176 if (unlikely(skb->len < len))
177 return -EINVAL;
178 if (unlikely(!pskb_may_pull(skb, len)))
179 return -ENOMEM;
180 return 0;
181}
182
183static bool arphdr_ok(struct sk_buff *skb)
184{
185 return pskb_may_pull(skb, skb_network_offset(skb) +
186 sizeof(struct arp_eth_header));
187}
188
189static int check_iphdr(struct sk_buff *skb)
190{
191 unsigned int nh_ofs = skb_network_offset(skb);
192 unsigned int ip_len;
193 int err;
194
195 err = check_header(skb, nh_ofs + sizeof(struct iphdr));
196 if (unlikely(err))
197 return err;
198
199 ip_len = ip_hdrlen(skb);
200 if (unlikely(ip_len < sizeof(struct iphdr) ||
201 skb->len < nh_ofs + ip_len))
202 return -EINVAL;
203
204 skb_set_transport_header(skb, nh_ofs + ip_len);
205 return 0;
206}
207
208static bool tcphdr_ok(struct sk_buff *skb)
209{
210 int th_ofs = skb_transport_offset(skb);
211 int tcp_len;
212
213 if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
214 return false;
215
216 tcp_len = tcp_hdrlen(skb);
217 if (unlikely(tcp_len < sizeof(struct tcphdr) ||
218 skb->len < th_ofs + tcp_len))
219 return false;
220
221 return true;
222}
223
224static bool udphdr_ok(struct sk_buff *skb)
225{
226 return pskb_may_pull(skb, skb_transport_offset(skb) +
227 sizeof(struct udphdr));
228}
229
230static bool sctphdr_ok(struct sk_buff *skb)
231{
232 return pskb_may_pull(skb, skb_transport_offset(skb) +
233 sizeof(struct sctphdr));
234}
235
236static bool icmphdr_ok(struct sk_buff *skb)
237{
238 return pskb_may_pull(skb, skb_transport_offset(skb) +
239 sizeof(struct icmphdr));
240}
241
242static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
243{
244 unsigned short frag_off;
245 unsigned int payload_ofs = 0;
246 unsigned int nh_ofs = skb_network_offset(skb);
247 unsigned int nh_len;
248 struct ipv6hdr *nh;
249 int err, nexthdr, flags = 0;
250
251 err = check_header(skb, nh_ofs + sizeof(*nh));
252 if (unlikely(err))
253 return err;
254
255 nh = ipv6_hdr(skb);
256
257 key->ip.proto = NEXTHDR_NONE;
258 key->ip.tos = ipv6_get_dsfield(nh);
259 key->ip.ttl = nh->hop_limit;
260 key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
261 key->ipv6.addr.src = nh->saddr;
262 key->ipv6.addr.dst = nh->daddr;
263
264 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
265 if (flags & IP6_FH_F_FRAG) {
266 if (frag_off) {
267 key->ip.frag = OVS_FRAG_TYPE_LATER;
268 key->ip.proto = nexthdr;
269 return 0;
270 }
271 key->ip.frag = OVS_FRAG_TYPE_FIRST;
272 } else {
273 key->ip.frag = OVS_FRAG_TYPE_NONE;
274 }
275
276 /* Delayed handling of error in ipv6_find_hdr() as it
277 * always sets flags and frag_off to a valid value which may be
278 * used to set key->ip.frag above.
279 */
280 if (unlikely(nexthdr < 0))
281 return -EPROTO;
282
283 nh_len = payload_ofs - nh_ofs;
284 skb_set_transport_header(skb, nh_ofs + nh_len);
285 key->ip.proto = nexthdr;
286 return nh_len;
287}
288
289static bool icmp6hdr_ok(struct sk_buff *skb)
290{
291 return pskb_may_pull(skb, skb_transport_offset(skb) +
292 sizeof(struct icmp6hdr));
293}
294
295/**
296 * parse_vlan_tag - Parse vlan tag from vlan header.
297 * @skb: skb containing frame to parse
298 * @key_vh: pointer to parsed vlan tag
299 * @untag_vlan: should the vlan header be removed from the frame
300 *
301 * Return: ERROR on memory error.
302 * %0 if it encounters a non-vlan or incomplete packet.
303 * %1 after successfully parsing vlan tag.
304 */
305static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
306 bool untag_vlan)
307{
308 struct vlan_head *vh = (struct vlan_head *)skb->data;
309
310 if (likely(!eth_type_vlan(vh->tpid)))
311 return 0;
312
313 if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
314 return 0;
315
316 if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
317 sizeof(__be16))))
318 return -ENOMEM;
319
320 vh = (struct vlan_head *)skb->data;
321 key_vh->tci = vh->tci | htons(VLAN_CFI_MASK);
322 key_vh->tpid = vh->tpid;
323
324 if (unlikely(untag_vlan)) {
325 int offset = skb->data - skb_mac_header(skb);
326 u16 tci;
327 int err;
328
329 __skb_push(skb, offset);
330 err = __skb_vlan_pop(skb, &tci);
331 __skb_pull(skb, offset);
332 if (err)
333 return err;
334 __vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
335 } else {
336 __skb_pull(skb, sizeof(struct vlan_head));
337 }
338 return 1;
339}
340
341static void clear_vlan(struct sw_flow_key *key)
342{
343 key->eth.vlan.tci = 0;
344 key->eth.vlan.tpid = 0;
345 key->eth.cvlan.tci = 0;
346 key->eth.cvlan.tpid = 0;
347}
348
349static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
350{
351 int res;
352
353 if (skb_vlan_tag_present(skb)) {
354 key->eth.vlan.tci = htons(skb->vlan_tci) | htons(VLAN_CFI_MASK);
355 key->eth.vlan.tpid = skb->vlan_proto;
356 } else {
357 /* Parse outer vlan tag in the non-accelerated case. */
358 res = parse_vlan_tag(skb, &key->eth.vlan, true);
359 if (res <= 0)
360 return res;
361 }
362
363 /* Parse inner vlan tag. */
364 res = parse_vlan_tag(skb, &key->eth.cvlan, false);
365 if (res <= 0)
366 return res;
367
368 return 0;
369}
370
371static __be16 parse_ethertype(struct sk_buff *skb)
372{
373 struct llc_snap_hdr {
374 u8 dsap; /* Always 0xAA */
375 u8 ssap; /* Always 0xAA */
376 u8 ctrl;
377 u8 oui[3];
378 __be16 ethertype;
379 };
380 struct llc_snap_hdr *llc;
381 __be16 proto;
382
383 proto = *(__be16 *) skb->data;
384 __skb_pull(skb, sizeof(__be16));
385
386 if (eth_proto_is_802_3(proto))
387 return proto;
388
389 if (skb->len < sizeof(struct llc_snap_hdr))
390 return htons(ETH_P_802_2);
391
392 if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
393 return htons(0);
394
395 llc = (struct llc_snap_hdr *) skb->data;
396 if (llc->dsap != LLC_SAP_SNAP ||
397 llc->ssap != LLC_SAP_SNAP ||
398 (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
399 return htons(ETH_P_802_2);
400
401 __skb_pull(skb, sizeof(struct llc_snap_hdr));
402
403 if (eth_proto_is_802_3(llc->ethertype))
404 return llc->ethertype;
405
406 return htons(ETH_P_802_2);
407}
408
409static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
410 int nh_len)
411{
412 struct icmp6hdr *icmp = icmp6_hdr(skb);
413
414 /* The ICMPv6 type and code fields use the 16-bit transport port
415 * fields, so we need to store them in 16-bit network byte order.
416 */
417 key->tp.src = htons(icmp->icmp6_type);
418 key->tp.dst = htons(icmp->icmp6_code);
419 memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
420
421 if (icmp->icmp6_code == 0 &&
422 (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
423 icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
424 int icmp_len = skb->len - skb_transport_offset(skb);
425 struct nd_msg *nd;
426 int offset;
427
428 /* In order to process neighbor discovery options, we need the
429 * entire packet.
430 */
431 if (unlikely(icmp_len < sizeof(*nd)))
432 return 0;
433
434 if (unlikely(skb_linearize(skb)))
435 return -ENOMEM;
436
437 nd = (struct nd_msg *)skb_transport_header(skb);
438 key->ipv6.nd.target = nd->target;
439
440 icmp_len -= sizeof(*nd);
441 offset = 0;
442 while (icmp_len >= 8) {
443 struct nd_opt_hdr *nd_opt =
444 (struct nd_opt_hdr *)(nd->opt + offset);
445 int opt_len = nd_opt->nd_opt_len * 8;
446
447 if (unlikely(!opt_len || opt_len > icmp_len))
448 return 0;
449
450 /* Store the link layer address if the appropriate
451 * option is provided. It is considered an error if
452 * the same link layer option is specified twice.
453 */
454 if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
455 && opt_len == 8) {
456 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
457 goto invalid;
458 ether_addr_copy(key->ipv6.nd.sll,
459 &nd->opt[offset+sizeof(*nd_opt)]);
460 } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
461 && opt_len == 8) {
462 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
463 goto invalid;
464 ether_addr_copy(key->ipv6.nd.tll,
465 &nd->opt[offset+sizeof(*nd_opt)]);
466 }
467
468 icmp_len -= opt_len;
469 offset += opt_len;
470 }
471 }
472
473 return 0;
474
475invalid:
476 memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
477 memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
478 memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
479
480 return 0;
481}
482
483static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
484{
485 struct nshhdr *nh;
486 unsigned int nh_ofs = skb_network_offset(skb);
487 u8 version, length;
488 int err;
489
490 err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN);
491 if (unlikely(err))
492 return err;
493
494 nh = nsh_hdr(skb);
495 version = nsh_get_ver(nh);
496 length = nsh_hdr_len(nh);
497
498 if (version != 0)
499 return -EINVAL;
500
501 err = check_header(skb, nh_ofs + length);
502 if (unlikely(err))
503 return err;
504
505 nh = nsh_hdr(skb);
506 key->nsh.base.flags = nsh_get_flags(nh);
507 key->nsh.base.ttl = nsh_get_ttl(nh);
508 key->nsh.base.mdtype = nh->mdtype;
509 key->nsh.base.np = nh->np;
510 key->nsh.base.path_hdr = nh->path_hdr;
511 switch (key->nsh.base.mdtype) {
512 case NSH_M_TYPE1:
513 if (length != NSH_M_TYPE1_LEN)
514 return -EINVAL;
515 memcpy(key->nsh.context, nh->md1.context,
516 sizeof(nh->md1));
517 break;
518 case NSH_M_TYPE2:
519 memset(key->nsh.context, 0,
520 sizeof(nh->md1));
521 break;
522 default:
523 return -EINVAL;
524 }
525
526 return 0;
527}
528
529/**
530 * key_extract_l3l4 - extracts L3/L4 header information.
531 * @skb: sk_buff that contains the frame, with skb->data pointing to the
532 * L3 header
533 * @key: output flow key
534 *
535 * Return: %0 if successful, otherwise a negative errno value.
536 */
537static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
538{
539 int error;
540
541 /* Network layer. */
542 if (key->eth.type == htons(ETH_P_IP)) {
543 struct iphdr *nh;
544 __be16 offset;
545
546 error = check_iphdr(skb);
547 if (unlikely(error)) {
548 memset(&key->ip, 0, sizeof(key->ip));
549 memset(&key->ipv4, 0, sizeof(key->ipv4));
550 if (error == -EINVAL) {
551 skb->transport_header = skb->network_header;
552 error = 0;
553 }
554 return error;
555 }
556
557 nh = ip_hdr(skb);
558 key->ipv4.addr.src = nh->saddr;
559 key->ipv4.addr.dst = nh->daddr;
560
561 key->ip.proto = nh->protocol;
562 key->ip.tos = nh->tos;
563 key->ip.ttl = nh->ttl;
564
565 offset = nh->frag_off & htons(IP_OFFSET);
566 if (offset) {
567 key->ip.frag = OVS_FRAG_TYPE_LATER;
568 memset(&key->tp, 0, sizeof(key->tp));
569 return 0;
570 }
571 if (nh->frag_off & htons(IP_MF) ||
572 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
573 key->ip.frag = OVS_FRAG_TYPE_FIRST;
574 else
575 key->ip.frag = OVS_FRAG_TYPE_NONE;
576
577 /* Transport layer. */
578 if (key->ip.proto == IPPROTO_TCP) {
579 if (tcphdr_ok(skb)) {
580 struct tcphdr *tcp = tcp_hdr(skb);
581 key->tp.src = tcp->source;
582 key->tp.dst = tcp->dest;
583 key->tp.flags = TCP_FLAGS_BE16(tcp);
584 } else {
585 memset(&key->tp, 0, sizeof(key->tp));
586 }
587
588 } else if (key->ip.proto == IPPROTO_UDP) {
589 if (udphdr_ok(skb)) {
590 struct udphdr *udp = udp_hdr(skb);
591 key->tp.src = udp->source;
592 key->tp.dst = udp->dest;
593 } else {
594 memset(&key->tp, 0, sizeof(key->tp));
595 }
596 } else if (key->ip.proto == IPPROTO_SCTP) {
597 if (sctphdr_ok(skb)) {
598 struct sctphdr *sctp = sctp_hdr(skb);
599 key->tp.src = sctp->source;
600 key->tp.dst = sctp->dest;
601 } else {
602 memset(&key->tp, 0, sizeof(key->tp));
603 }
604 } else if (key->ip.proto == IPPROTO_ICMP) {
605 if (icmphdr_ok(skb)) {
606 struct icmphdr *icmp = icmp_hdr(skb);
607 /* The ICMP type and code fields use the 16-bit
608 * transport port fields, so we need to store
609 * them in 16-bit network byte order. */
610 key->tp.src = htons(icmp->type);
611 key->tp.dst = htons(icmp->code);
612 } else {
613 memset(&key->tp, 0, sizeof(key->tp));
614 }
615 }
616
617 } else if (key->eth.type == htons(ETH_P_ARP) ||
618 key->eth.type == htons(ETH_P_RARP)) {
619 struct arp_eth_header *arp;
620 bool arp_available = arphdr_ok(skb);
621
622 arp = (struct arp_eth_header *)skb_network_header(skb);
623
624 if (arp_available &&
625 arp->ar_hrd == htons(ARPHRD_ETHER) &&
626 arp->ar_pro == htons(ETH_P_IP) &&
627 arp->ar_hln == ETH_ALEN &&
628 arp->ar_pln == 4) {
629
630 /* We only match on the lower 8 bits of the opcode. */
631 if (ntohs(arp->ar_op) <= 0xff)
632 key->ip.proto = ntohs(arp->ar_op);
633 else
634 key->ip.proto = 0;
635
636 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
637 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
638 ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
639 ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
640 } else {
641 memset(&key->ip, 0, sizeof(key->ip));
642 memset(&key->ipv4, 0, sizeof(key->ipv4));
643 }
644 } else if (eth_p_mpls(key->eth.type)) {
645 u8 label_count = 1;
646
647 memset(&key->mpls, 0, sizeof(key->mpls));
648 skb_set_inner_network_header(skb, skb->mac_len);
649 while (1) {
650 __be32 lse;
651
652 error = check_header(skb, skb->mac_len +
653 label_count * MPLS_HLEN);
654 if (unlikely(error))
655 return 0;
656
657 memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
658
659 if (label_count <= MPLS_LABEL_DEPTH)
660 memcpy(&key->mpls.lse[label_count - 1], &lse,
661 MPLS_HLEN);
662
663 skb_set_inner_network_header(skb, skb->mac_len +
664 label_count * MPLS_HLEN);
665 if (lse & htonl(MPLS_LS_S_MASK))
666 break;
667
668 label_count++;
669 }
670 if (label_count > MPLS_LABEL_DEPTH)
671 label_count = MPLS_LABEL_DEPTH;
672
673 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0);
674 } else if (key->eth.type == htons(ETH_P_IPV6)) {
675 int nh_len; /* IPv6 Header + Extensions */
676
677 nh_len = parse_ipv6hdr(skb, key);
678 if (unlikely(nh_len < 0)) {
679 switch (nh_len) {
680 case -EINVAL:
681 memset(&key->ip, 0, sizeof(key->ip));
682 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
683 fallthrough;
684 case -EPROTO:
685 skb->transport_header = skb->network_header;
686 error = 0;
687 break;
688 default:
689 error = nh_len;
690 }
691 return error;
692 }
693
694 if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
695 memset(&key->tp, 0, sizeof(key->tp));
696 return 0;
697 }
698 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
699 key->ip.frag = OVS_FRAG_TYPE_FIRST;
700
701 /* Transport layer. */
702 if (key->ip.proto == NEXTHDR_TCP) {
703 if (tcphdr_ok(skb)) {
704 struct tcphdr *tcp = tcp_hdr(skb);
705 key->tp.src = tcp->source;
706 key->tp.dst = tcp->dest;
707 key->tp.flags = TCP_FLAGS_BE16(tcp);
708 } else {
709 memset(&key->tp, 0, sizeof(key->tp));
710 }
711 } else if (key->ip.proto == NEXTHDR_UDP) {
712 if (udphdr_ok(skb)) {
713 struct udphdr *udp = udp_hdr(skb);
714 key->tp.src = udp->source;
715 key->tp.dst = udp->dest;
716 } else {
717 memset(&key->tp, 0, sizeof(key->tp));
718 }
719 } else if (key->ip.proto == NEXTHDR_SCTP) {
720 if (sctphdr_ok(skb)) {
721 struct sctphdr *sctp = sctp_hdr(skb);
722 key->tp.src = sctp->source;
723 key->tp.dst = sctp->dest;
724 } else {
725 memset(&key->tp, 0, sizeof(key->tp));
726 }
727 } else if (key->ip.proto == NEXTHDR_ICMP) {
728 if (icmp6hdr_ok(skb)) {
729 error = parse_icmpv6(skb, key, nh_len);
730 if (error)
731 return error;
732 } else {
733 memset(&key->tp, 0, sizeof(key->tp));
734 }
735 }
736 } else if (key->eth.type == htons(ETH_P_NSH)) {
737 error = parse_nsh(skb, key);
738 if (error)
739 return error;
740 }
741 return 0;
742}
743
744/**
745 * key_extract - extracts a flow key from an Ethernet frame.
746 * @skb: sk_buff that contains the frame, with skb->data pointing to the
747 * Ethernet header
748 * @key: output flow key
749 *
750 * The caller must ensure that skb->len >= ETH_HLEN.
751 *
752 * Initializes @skb header fields as follows:
753 *
754 * - skb->mac_header: the L2 header.
755 *
756 * - skb->network_header: just past the L2 header, or just past the
757 * VLAN header, to the first byte of the L2 payload.
758 *
759 * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
760 * on output, then just past the IP header, if one is present and
761 * of a correct length, otherwise the same as skb->network_header.
762 * For other key->eth.type values it is left untouched.
763 *
764 * - skb->protocol: the type of the data starting at skb->network_header.
765 * Equals to key->eth.type.
766 *
767 * Return: %0 if successful, otherwise a negative errno value.
768 */
769static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
770{
771 struct ethhdr *eth;
772
773 /* Flags are always used as part of stats */
774 key->tp.flags = 0;
775
776 skb_reset_mac_header(skb);
777
778 /* Link layer. */
779 clear_vlan(key);
780 if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
781 if (unlikely(eth_type_vlan(skb->protocol)))
782 return -EINVAL;
783
784 skb_reset_network_header(skb);
785 key->eth.type = skb->protocol;
786 } else {
787 eth = eth_hdr(skb);
788 ether_addr_copy(key->eth.src, eth->h_source);
789 ether_addr_copy(key->eth.dst, eth->h_dest);
790
791 __skb_pull(skb, 2 * ETH_ALEN);
792 /* We are going to push all headers that we pull, so no need to
793 * update skb->csum here.
794 */
795
796 if (unlikely(parse_vlan(skb, key)))
797 return -ENOMEM;
798
799 key->eth.type = parse_ethertype(skb);
800 if (unlikely(key->eth.type == htons(0)))
801 return -ENOMEM;
802
803 /* Multiple tagged packets need to retain TPID to satisfy
804 * skb_vlan_pop(), which will later shift the ethertype into
805 * skb->protocol.
806 */
807 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
808 skb->protocol = key->eth.cvlan.tpid;
809 else
810 skb->protocol = key->eth.type;
811
812 skb_reset_network_header(skb);
813 __skb_push(skb, skb->data - skb_mac_header(skb));
814 }
815
816 skb_reset_mac_len(skb);
817
818 /* Fill out L3/L4 key info, if any */
819 return key_extract_l3l4(skb, key);
820}
821
822/* In the case of conntrack fragment handling it expects L3 headers,
823 * add a helper.
824 */
825int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
826{
827 return key_extract_l3l4(skb, key);
828}
829
830int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
831{
832 int res;
833
834 res = key_extract(skb, key);
835 if (!res)
836 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
837
838 return res;
839}
840
841static int key_extract_mac_proto(struct sk_buff *skb)
842{
843 switch (skb->dev->type) {
844 case ARPHRD_ETHER:
845 return MAC_PROTO_ETHERNET;
846 case ARPHRD_NONE:
847 if (skb->protocol == htons(ETH_P_TEB))
848 return MAC_PROTO_ETHERNET;
849 return MAC_PROTO_NONE;
850 }
851 WARN_ON_ONCE(1);
852 return -EINVAL;
853}
854
855int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
856 struct sk_buff *skb, struct sw_flow_key *key)
857{
858#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
859 struct tc_skb_ext *tc_ext;
860#endif
861 bool post_ct = false;
862 int res, err;
863
864 /* Extract metadata from packet. */
865 if (tun_info) {
866 key->tun_proto = ip_tunnel_info_af(tun_info);
867 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
868
869 if (tun_info->options_len) {
870 BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
871 8)) - 1
872 > sizeof(key->tun_opts));
873
874 ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
875 tun_info);
876 key->tun_opts_len = tun_info->options_len;
877 } else {
878 key->tun_opts_len = 0;
879 }
880 } else {
881 key->tun_proto = 0;
882 key->tun_opts_len = 0;
883 memset(&key->tun_key, 0, sizeof(key->tun_key));
884 }
885
886 key->phy.priority = skb->priority;
887 key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
888 key->phy.skb_mark = skb->mark;
889 key->ovs_flow_hash = 0;
890 res = key_extract_mac_proto(skb);
891 if (res < 0)
892 return res;
893 key->mac_proto = res;
894
895#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
896 if (static_branch_unlikely(&tc_recirc_sharing_support)) {
897 tc_ext = skb_ext_find(skb, TC_SKB_EXT);
898 key->recirc_id = tc_ext ? tc_ext->chain : 0;
899 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0;
900 post_ct = tc_ext ? tc_ext->post_ct : false;
901 } else {
902 key->recirc_id = 0;
903 }
904#else
905 key->recirc_id = 0;
906#endif
907
908 err = key_extract(skb, key);
909 if (!err)
910 ovs_ct_fill_key(skb, key, post_ct); /* Must be after key_extract(). */
911 return err;
912}
913
914int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
915 struct sk_buff *skb,
916 struct sw_flow_key *key, bool log)
917{
918 const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
919 u64 attrs = 0;
920 int err;
921
922 err = parse_flow_nlattrs(attr, a, &attrs, log);
923 if (err)
924 return -EINVAL;
925
926 /* Extract metadata from netlink attributes. */
927 err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
928 if (err)
929 return err;
930
931 /* key_extract assumes that skb->protocol is set-up for
932 * layer 3 packets which is the case for other callers,
933 * in particular packets received from the network stack.
934 * Here the correct value can be set from the metadata
935 * extracted above.
936 * For L2 packet key eth type would be zero. skb protocol
937 * would be set to correct value later during key-extact.
938 */
939
940 skb->protocol = key->eth.type;
941 err = key_extract(skb, key);
942 if (err)
943 return err;
944
945 /* Check that we have conntrack original direction tuple metadata only
946 * for packets for which it makes sense. Otherwise the key may be
947 * corrupted due to overlapping key fields.
948 */
949 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
950 key->eth.type != htons(ETH_P_IP))
951 return -EINVAL;
952 if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
953 (key->eth.type != htons(ETH_P_IPV6) ||
954 sw_flow_key_is_nd(key)))
955 return -EINVAL;
956
957 return 0;
958}
1/*
2 * Copyright (c) 2007-2013 Nicira, Inc.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of version 2 of the GNU General Public
6 * License as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16 * 02110-1301, USA
17 */
18
19#include "flow.h"
20#include "datapath.h"
21#include <linux/uaccess.h>
22#include <linux/netdevice.h>
23#include <linux/etherdevice.h>
24#include <linux/if_ether.h>
25#include <linux/if_vlan.h>
26#include <net/llc_pdu.h>
27#include <linux/kernel.h>
28#include <linux/jhash.h>
29#include <linux/jiffies.h>
30#include <linux/llc.h>
31#include <linux/module.h>
32#include <linux/in.h>
33#include <linux/rcupdate.h>
34#include <linux/if_arp.h>
35#include <linux/ip.h>
36#include <linux/ipv6.h>
37#include <linux/sctp.h>
38#include <linux/smp.h>
39#include <linux/tcp.h>
40#include <linux/udp.h>
41#include <linux/icmp.h>
42#include <linux/icmpv6.h>
43#include <linux/rculist.h>
44#include <net/ip.h>
45#include <net/ip_tunnels.h>
46#include <net/ipv6.h>
47#include <net/ndisc.h>
48
49u64 ovs_flow_used_time(unsigned long flow_jiffies)
50{
51 struct timespec cur_ts;
52 u64 cur_ms, idle_ms;
53
54 ktime_get_ts(&cur_ts);
55 idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
56 cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
57 cur_ts.tv_nsec / NSEC_PER_MSEC;
58
59 return cur_ms - idle_ms;
60}
61
62#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
63
64void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb)
65{
66 struct flow_stats *stats;
67 __be16 tcp_flags = 0;
68
69 if (!flow->stats.is_percpu)
70 stats = flow->stats.stat;
71 else
72 stats = this_cpu_ptr(flow->stats.cpu_stats);
73
74 if ((flow->key.eth.type == htons(ETH_P_IP) ||
75 flow->key.eth.type == htons(ETH_P_IPV6)) &&
76 flow->key.ip.frag != OVS_FRAG_TYPE_LATER &&
77 flow->key.ip.proto == IPPROTO_TCP &&
78 likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
79 tcp_flags = TCP_FLAGS_BE16(tcp_hdr(skb));
80 }
81
82 spin_lock(&stats->lock);
83 stats->used = jiffies;
84 stats->packet_count++;
85 stats->byte_count += skb->len;
86 stats->tcp_flags |= tcp_flags;
87 spin_unlock(&stats->lock);
88}
89
90static void stats_read(struct flow_stats *stats,
91 struct ovs_flow_stats *ovs_stats,
92 unsigned long *used, __be16 *tcp_flags)
93{
94 spin_lock(&stats->lock);
95 if (!*used || time_after(stats->used, *used))
96 *used = stats->used;
97 *tcp_flags |= stats->tcp_flags;
98 ovs_stats->n_packets += stats->packet_count;
99 ovs_stats->n_bytes += stats->byte_count;
100 spin_unlock(&stats->lock);
101}
102
103void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats,
104 unsigned long *used, __be16 *tcp_flags)
105{
106 int cpu;
107
108 *used = 0;
109 *tcp_flags = 0;
110 memset(ovs_stats, 0, sizeof(*ovs_stats));
111
112 local_bh_disable();
113 if (!flow->stats.is_percpu) {
114 stats_read(flow->stats.stat, ovs_stats, used, tcp_flags);
115 } else {
116 for_each_possible_cpu(cpu) {
117 struct flow_stats *stats;
118
119 stats = per_cpu_ptr(flow->stats.cpu_stats, cpu);
120 stats_read(stats, ovs_stats, used, tcp_flags);
121 }
122 }
123 local_bh_enable();
124}
125
126static void stats_reset(struct flow_stats *stats)
127{
128 spin_lock(&stats->lock);
129 stats->used = 0;
130 stats->packet_count = 0;
131 stats->byte_count = 0;
132 stats->tcp_flags = 0;
133 spin_unlock(&stats->lock);
134}
135
136void ovs_flow_stats_clear(struct sw_flow *flow)
137{
138 int cpu;
139
140 local_bh_disable();
141 if (!flow->stats.is_percpu) {
142 stats_reset(flow->stats.stat);
143 } else {
144 for_each_possible_cpu(cpu) {
145 stats_reset(per_cpu_ptr(flow->stats.cpu_stats, cpu));
146 }
147 }
148 local_bh_enable();
149}
150
151static int check_header(struct sk_buff *skb, int len)
152{
153 if (unlikely(skb->len < len))
154 return -EINVAL;
155 if (unlikely(!pskb_may_pull(skb, len)))
156 return -ENOMEM;
157 return 0;
158}
159
160static bool arphdr_ok(struct sk_buff *skb)
161{
162 return pskb_may_pull(skb, skb_network_offset(skb) +
163 sizeof(struct arp_eth_header));
164}
165
166static int check_iphdr(struct sk_buff *skb)
167{
168 unsigned int nh_ofs = skb_network_offset(skb);
169 unsigned int ip_len;
170 int err;
171
172 err = check_header(skb, nh_ofs + sizeof(struct iphdr));
173 if (unlikely(err))
174 return err;
175
176 ip_len = ip_hdrlen(skb);
177 if (unlikely(ip_len < sizeof(struct iphdr) ||
178 skb->len < nh_ofs + ip_len))
179 return -EINVAL;
180
181 skb_set_transport_header(skb, nh_ofs + ip_len);
182 return 0;
183}
184
185static bool tcphdr_ok(struct sk_buff *skb)
186{
187 int th_ofs = skb_transport_offset(skb);
188 int tcp_len;
189
190 if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
191 return false;
192
193 tcp_len = tcp_hdrlen(skb);
194 if (unlikely(tcp_len < sizeof(struct tcphdr) ||
195 skb->len < th_ofs + tcp_len))
196 return false;
197
198 return true;
199}
200
201static bool udphdr_ok(struct sk_buff *skb)
202{
203 return pskb_may_pull(skb, skb_transport_offset(skb) +
204 sizeof(struct udphdr));
205}
206
207static bool sctphdr_ok(struct sk_buff *skb)
208{
209 return pskb_may_pull(skb, skb_transport_offset(skb) +
210 sizeof(struct sctphdr));
211}
212
213static bool icmphdr_ok(struct sk_buff *skb)
214{
215 return pskb_may_pull(skb, skb_transport_offset(skb) +
216 sizeof(struct icmphdr));
217}
218
219static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
220{
221 unsigned int nh_ofs = skb_network_offset(skb);
222 unsigned int nh_len;
223 int payload_ofs;
224 struct ipv6hdr *nh;
225 uint8_t nexthdr;
226 __be16 frag_off;
227 int err;
228
229 err = check_header(skb, nh_ofs + sizeof(*nh));
230 if (unlikely(err))
231 return err;
232
233 nh = ipv6_hdr(skb);
234 nexthdr = nh->nexthdr;
235 payload_ofs = (u8 *)(nh + 1) - skb->data;
236
237 key->ip.proto = NEXTHDR_NONE;
238 key->ip.tos = ipv6_get_dsfield(nh);
239 key->ip.ttl = nh->hop_limit;
240 key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
241 key->ipv6.addr.src = nh->saddr;
242 key->ipv6.addr.dst = nh->daddr;
243
244 payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
245 if (unlikely(payload_ofs < 0))
246 return -EINVAL;
247
248 if (frag_off) {
249 if (frag_off & htons(~0x7))
250 key->ip.frag = OVS_FRAG_TYPE_LATER;
251 else
252 key->ip.frag = OVS_FRAG_TYPE_FIRST;
253 }
254
255 nh_len = payload_ofs - nh_ofs;
256 skb_set_transport_header(skb, nh_ofs + nh_len);
257 key->ip.proto = nexthdr;
258 return nh_len;
259}
260
261static bool icmp6hdr_ok(struct sk_buff *skb)
262{
263 return pskb_may_pull(skb, skb_transport_offset(skb) +
264 sizeof(struct icmp6hdr));
265}
266
267static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
268{
269 struct qtag_prefix {
270 __be16 eth_type; /* ETH_P_8021Q */
271 __be16 tci;
272 };
273 struct qtag_prefix *qp;
274
275 if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
276 return 0;
277
278 if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
279 sizeof(__be16))))
280 return -ENOMEM;
281
282 qp = (struct qtag_prefix *) skb->data;
283 key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
284 __skb_pull(skb, sizeof(struct qtag_prefix));
285
286 return 0;
287}
288
289static __be16 parse_ethertype(struct sk_buff *skb)
290{
291 struct llc_snap_hdr {
292 u8 dsap; /* Always 0xAA */
293 u8 ssap; /* Always 0xAA */
294 u8 ctrl;
295 u8 oui[3];
296 __be16 ethertype;
297 };
298 struct llc_snap_hdr *llc;
299 __be16 proto;
300
301 proto = *(__be16 *) skb->data;
302 __skb_pull(skb, sizeof(__be16));
303
304 if (ntohs(proto) >= ETH_P_802_3_MIN)
305 return proto;
306
307 if (skb->len < sizeof(struct llc_snap_hdr))
308 return htons(ETH_P_802_2);
309
310 if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
311 return htons(0);
312
313 llc = (struct llc_snap_hdr *) skb->data;
314 if (llc->dsap != LLC_SAP_SNAP ||
315 llc->ssap != LLC_SAP_SNAP ||
316 (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
317 return htons(ETH_P_802_2);
318
319 __skb_pull(skb, sizeof(struct llc_snap_hdr));
320
321 if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
322 return llc->ethertype;
323
324 return htons(ETH_P_802_2);
325}
326
327static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
328 int nh_len)
329{
330 struct icmp6hdr *icmp = icmp6_hdr(skb);
331
332 /* The ICMPv6 type and code fields use the 16-bit transport port
333 * fields, so we need to store them in 16-bit network byte order.
334 */
335 key->ipv6.tp.src = htons(icmp->icmp6_type);
336 key->ipv6.tp.dst = htons(icmp->icmp6_code);
337
338 if (icmp->icmp6_code == 0 &&
339 (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
340 icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
341 int icmp_len = skb->len - skb_transport_offset(skb);
342 struct nd_msg *nd;
343 int offset;
344
345 /* In order to process neighbor discovery options, we need the
346 * entire packet.
347 */
348 if (unlikely(icmp_len < sizeof(*nd)))
349 return 0;
350
351 if (unlikely(skb_linearize(skb)))
352 return -ENOMEM;
353
354 nd = (struct nd_msg *)skb_transport_header(skb);
355 key->ipv6.nd.target = nd->target;
356
357 icmp_len -= sizeof(*nd);
358 offset = 0;
359 while (icmp_len >= 8) {
360 struct nd_opt_hdr *nd_opt =
361 (struct nd_opt_hdr *)(nd->opt + offset);
362 int opt_len = nd_opt->nd_opt_len * 8;
363
364 if (unlikely(!opt_len || opt_len > icmp_len))
365 return 0;
366
367 /* Store the link layer address if the appropriate
368 * option is provided. It is considered an error if
369 * the same link layer option is specified twice.
370 */
371 if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
372 && opt_len == 8) {
373 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
374 goto invalid;
375 memcpy(key->ipv6.nd.sll,
376 &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
377 } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
378 && opt_len == 8) {
379 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
380 goto invalid;
381 memcpy(key->ipv6.nd.tll,
382 &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
383 }
384
385 icmp_len -= opt_len;
386 offset += opt_len;
387 }
388 }
389
390 return 0;
391
392invalid:
393 memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
394 memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
395 memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
396
397 return 0;
398}
399
400/**
401 * ovs_flow_extract - extracts a flow key from an Ethernet frame.
402 * @skb: sk_buff that contains the frame, with skb->data pointing to the
403 * Ethernet header
404 * @in_port: port number on which @skb was received.
405 * @key: output flow key
406 *
407 * The caller must ensure that skb->len >= ETH_HLEN.
408 *
409 * Returns 0 if successful, otherwise a negative errno value.
410 *
411 * Initializes @skb header pointers as follows:
412 *
413 * - skb->mac_header: the Ethernet header.
414 *
415 * - skb->network_header: just past the Ethernet header, or just past the
416 * VLAN header, to the first byte of the Ethernet payload.
417 *
418 * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
419 * on output, then just past the IP header, if one is present and
420 * of a correct length, otherwise the same as skb->network_header.
421 * For other key->eth.type values it is left untouched.
422 */
423int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key)
424{
425 int error;
426 struct ethhdr *eth;
427
428 memset(key, 0, sizeof(*key));
429
430 key->phy.priority = skb->priority;
431 if (OVS_CB(skb)->tun_key)
432 memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
433 key->phy.in_port = in_port;
434 key->phy.skb_mark = skb->mark;
435
436 skb_reset_mac_header(skb);
437
438 /* Link layer. We are guaranteed to have at least the 14 byte Ethernet
439 * header in the linear data area.
440 */
441 eth = eth_hdr(skb);
442 memcpy(key->eth.src, eth->h_source, ETH_ALEN);
443 memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
444
445 __skb_pull(skb, 2 * ETH_ALEN);
446 /* We are going to push all headers that we pull, so no need to
447 * update skb->csum here.
448 */
449
450 if (vlan_tx_tag_present(skb))
451 key->eth.tci = htons(skb->vlan_tci);
452 else if (eth->h_proto == htons(ETH_P_8021Q))
453 if (unlikely(parse_vlan(skb, key)))
454 return -ENOMEM;
455
456 key->eth.type = parse_ethertype(skb);
457 if (unlikely(key->eth.type == htons(0)))
458 return -ENOMEM;
459
460 skb_reset_network_header(skb);
461 __skb_push(skb, skb->data - skb_mac_header(skb));
462
463 /* Network layer. */
464 if (key->eth.type == htons(ETH_P_IP)) {
465 struct iphdr *nh;
466 __be16 offset;
467
468 error = check_iphdr(skb);
469 if (unlikely(error)) {
470 if (error == -EINVAL) {
471 skb->transport_header = skb->network_header;
472 error = 0;
473 }
474 return error;
475 }
476
477 nh = ip_hdr(skb);
478 key->ipv4.addr.src = nh->saddr;
479 key->ipv4.addr.dst = nh->daddr;
480
481 key->ip.proto = nh->protocol;
482 key->ip.tos = nh->tos;
483 key->ip.ttl = nh->ttl;
484
485 offset = nh->frag_off & htons(IP_OFFSET);
486 if (offset) {
487 key->ip.frag = OVS_FRAG_TYPE_LATER;
488 return 0;
489 }
490 if (nh->frag_off & htons(IP_MF) ||
491 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
492 key->ip.frag = OVS_FRAG_TYPE_FIRST;
493
494 /* Transport layer. */
495 if (key->ip.proto == IPPROTO_TCP) {
496 if (tcphdr_ok(skb)) {
497 struct tcphdr *tcp = tcp_hdr(skb);
498 key->ipv4.tp.src = tcp->source;
499 key->ipv4.tp.dst = tcp->dest;
500 key->ipv4.tp.flags = TCP_FLAGS_BE16(tcp);
501 }
502 } else if (key->ip.proto == IPPROTO_UDP) {
503 if (udphdr_ok(skb)) {
504 struct udphdr *udp = udp_hdr(skb);
505 key->ipv4.tp.src = udp->source;
506 key->ipv4.tp.dst = udp->dest;
507 }
508 } else if (key->ip.proto == IPPROTO_SCTP) {
509 if (sctphdr_ok(skb)) {
510 struct sctphdr *sctp = sctp_hdr(skb);
511 key->ipv4.tp.src = sctp->source;
512 key->ipv4.tp.dst = sctp->dest;
513 }
514 } else if (key->ip.proto == IPPROTO_ICMP) {
515 if (icmphdr_ok(skb)) {
516 struct icmphdr *icmp = icmp_hdr(skb);
517 /* The ICMP type and code fields use the 16-bit
518 * transport port fields, so we need to store
519 * them in 16-bit network byte order. */
520 key->ipv4.tp.src = htons(icmp->type);
521 key->ipv4.tp.dst = htons(icmp->code);
522 }
523 }
524
525 } else if ((key->eth.type == htons(ETH_P_ARP) ||
526 key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
527 struct arp_eth_header *arp;
528
529 arp = (struct arp_eth_header *)skb_network_header(skb);
530
531 if (arp->ar_hrd == htons(ARPHRD_ETHER)
532 && arp->ar_pro == htons(ETH_P_IP)
533 && arp->ar_hln == ETH_ALEN
534 && arp->ar_pln == 4) {
535
536 /* We only match on the lower 8 bits of the opcode. */
537 if (ntohs(arp->ar_op) <= 0xff)
538 key->ip.proto = ntohs(arp->ar_op);
539 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
540 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
541 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
542 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
543 }
544 } else if (key->eth.type == htons(ETH_P_IPV6)) {
545 int nh_len; /* IPv6 Header + Extensions */
546
547 nh_len = parse_ipv6hdr(skb, key);
548 if (unlikely(nh_len < 0)) {
549 if (nh_len == -EINVAL) {
550 skb->transport_header = skb->network_header;
551 error = 0;
552 } else {
553 error = nh_len;
554 }
555 return error;
556 }
557
558 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
559 return 0;
560 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
561 key->ip.frag = OVS_FRAG_TYPE_FIRST;
562
563 /* Transport layer. */
564 if (key->ip.proto == NEXTHDR_TCP) {
565 if (tcphdr_ok(skb)) {
566 struct tcphdr *tcp = tcp_hdr(skb);
567 key->ipv6.tp.src = tcp->source;
568 key->ipv6.tp.dst = tcp->dest;
569 key->ipv6.tp.flags = TCP_FLAGS_BE16(tcp);
570 }
571 } else if (key->ip.proto == NEXTHDR_UDP) {
572 if (udphdr_ok(skb)) {
573 struct udphdr *udp = udp_hdr(skb);
574 key->ipv6.tp.src = udp->source;
575 key->ipv6.tp.dst = udp->dest;
576 }
577 } else if (key->ip.proto == NEXTHDR_SCTP) {
578 if (sctphdr_ok(skb)) {
579 struct sctphdr *sctp = sctp_hdr(skb);
580 key->ipv6.tp.src = sctp->source;
581 key->ipv6.tp.dst = sctp->dest;
582 }
583 } else if (key->ip.proto == NEXTHDR_ICMP) {
584 if (icmp6hdr_ok(skb)) {
585 error = parse_icmpv6(skb, key, nh_len);
586 if (error)
587 return error;
588 }
589 }
590 }
591
592 return 0;
593}