Merge branch 'pm-cpufreq'
[linux-2.6-microblaze.git] / net / openvswitch / flow.c
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
44 u64 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
59 void 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;
120 unlock:
121         spin_unlock(&stats->lock);
122 }
123
124 /* Must be called with rcu_read_lock or ovs_mutex. */
125 void 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. */
155 void 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
174 static 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
183 static 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
189 static 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
208 static 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
224 static bool udphdr_ok(struct sk_buff *skb)
225 {
226         return pskb_may_pull(skb, skb_transport_offset(skb) +
227                                   sizeof(struct udphdr));
228 }
229
230 static bool sctphdr_ok(struct sk_buff *skb)
231 {
232         return pskb_may_pull(skb, skb_transport_offset(skb) +
233                                   sizeof(struct sctphdr));
234 }
235
236 static bool icmphdr_ok(struct sk_buff *skb)
237 {
238         return pskb_may_pull(skb, skb_transport_offset(skb) +
239                                   sizeof(struct icmphdr));
240 }
241
242 static 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
289 static 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 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  * Returns ERROR on memory error.
302  * Returns 0 if it encounters a non-vlan or incomplete packet.
303  * Returns 1 after successfully parsing vlan tag.
304  */
305 static 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
341 static 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
349 static 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
371 static __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
409 static 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
475 invalid:
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
483 static 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  */
536 static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
537 {
538         int error;
539
540         /* Network layer. */
541         if (key->eth.type == htons(ETH_P_IP)) {
542                 struct iphdr *nh;
543                 __be16 offset;
544
545                 error = check_iphdr(skb);
546                 if (unlikely(error)) {
547                         memset(&key->ip, 0, sizeof(key->ip));
548                         memset(&key->ipv4, 0, sizeof(key->ipv4));
549                         if (error == -EINVAL) {
550                                 skb->transport_header = skb->network_header;
551                                 error = 0;
552                         }
553                         return error;
554                 }
555
556                 nh = ip_hdr(skb);
557                 key->ipv4.addr.src = nh->saddr;
558                 key->ipv4.addr.dst = nh->daddr;
559
560                 key->ip.proto = nh->protocol;
561                 key->ip.tos = nh->tos;
562                 key->ip.ttl = nh->ttl;
563
564                 offset = nh->frag_off & htons(IP_OFFSET);
565                 if (offset) {
566                         key->ip.frag = OVS_FRAG_TYPE_LATER;
567                         memset(&key->tp, 0, sizeof(key->tp));
568                         return 0;
569                 }
570                 if (nh->frag_off & htons(IP_MF) ||
571                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
572                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
573                 else
574                         key->ip.frag = OVS_FRAG_TYPE_NONE;
575
576                 /* Transport layer. */
577                 if (key->ip.proto == IPPROTO_TCP) {
578                         if (tcphdr_ok(skb)) {
579                                 struct tcphdr *tcp = tcp_hdr(skb);
580                                 key->tp.src = tcp->source;
581                                 key->tp.dst = tcp->dest;
582                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
583                         } else {
584                                 memset(&key->tp, 0, sizeof(key->tp));
585                         }
586
587                 } else if (key->ip.proto == IPPROTO_UDP) {
588                         if (udphdr_ok(skb)) {
589                                 struct udphdr *udp = udp_hdr(skb);
590                                 key->tp.src = udp->source;
591                                 key->tp.dst = udp->dest;
592                         } else {
593                                 memset(&key->tp, 0, sizeof(key->tp));
594                         }
595                 } else if (key->ip.proto == IPPROTO_SCTP) {
596                         if (sctphdr_ok(skb)) {
597                                 struct sctphdr *sctp = sctp_hdr(skb);
598                                 key->tp.src = sctp->source;
599                                 key->tp.dst = sctp->dest;
600                         } else {
601                                 memset(&key->tp, 0, sizeof(key->tp));
602                         }
603                 } else if (key->ip.proto == IPPROTO_ICMP) {
604                         if (icmphdr_ok(skb)) {
605                                 struct icmphdr *icmp = icmp_hdr(skb);
606                                 /* The ICMP type and code fields use the 16-bit
607                                  * transport port fields, so we need to store
608                                  * them in 16-bit network byte order. */
609                                 key->tp.src = htons(icmp->type);
610                                 key->tp.dst = htons(icmp->code);
611                         } else {
612                                 memset(&key->tp, 0, sizeof(key->tp));
613                         }
614                 }
615
616         } else if (key->eth.type == htons(ETH_P_ARP) ||
617                    key->eth.type == htons(ETH_P_RARP)) {
618                 struct arp_eth_header *arp;
619                 bool arp_available = arphdr_ok(skb);
620
621                 arp = (struct arp_eth_header *)skb_network_header(skb);
622
623                 if (arp_available &&
624                     arp->ar_hrd == htons(ARPHRD_ETHER) &&
625                     arp->ar_pro == htons(ETH_P_IP) &&
626                     arp->ar_hln == ETH_ALEN &&
627                     arp->ar_pln == 4) {
628
629                         /* We only match on the lower 8 bits of the opcode. */
630                         if (ntohs(arp->ar_op) <= 0xff)
631                                 key->ip.proto = ntohs(arp->ar_op);
632                         else
633                                 key->ip.proto = 0;
634
635                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
636                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
637                         ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
638                         ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
639                 } else {
640                         memset(&key->ip, 0, sizeof(key->ip));
641                         memset(&key->ipv4, 0, sizeof(key->ipv4));
642                 }
643         } else if (eth_p_mpls(key->eth.type)) {
644                 u8 label_count = 1;
645
646                 memset(&key->mpls, 0, sizeof(key->mpls));
647                 skb_set_inner_network_header(skb, skb->mac_len);
648                 while (1) {
649                         __be32 lse;
650
651                         error = check_header(skb, skb->mac_len +
652                                              label_count * MPLS_HLEN);
653                         if (unlikely(error))
654                                 return 0;
655
656                         memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
657
658                         if (label_count <= MPLS_LABEL_DEPTH)
659                                 memcpy(&key->mpls.lse[label_count - 1], &lse,
660                                        MPLS_HLEN);
661
662                         skb_set_inner_network_header(skb, skb->mac_len +
663                                                      label_count * MPLS_HLEN);
664                         if (lse & htonl(MPLS_LS_S_MASK))
665                                 break;
666
667                         label_count++;
668                 }
669                 if (label_count > MPLS_LABEL_DEPTH)
670                         label_count = MPLS_LABEL_DEPTH;
671
672                 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0);
673         } else if (key->eth.type == htons(ETH_P_IPV6)) {
674                 int nh_len;             /* IPv6 Header + Extensions */
675
676                 nh_len = parse_ipv6hdr(skb, key);
677                 if (unlikely(nh_len < 0)) {
678                         switch (nh_len) {
679                         case -EINVAL:
680                                 memset(&key->ip, 0, sizeof(key->ip));
681                                 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
682                                 fallthrough;
683                         case -EPROTO:
684                                 skb->transport_header = skb->network_header;
685                                 error = 0;
686                                 break;
687                         default:
688                                 error = nh_len;
689                         }
690                         return error;
691                 }
692
693                 if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
694                         memset(&key->tp, 0, sizeof(key->tp));
695                         return 0;
696                 }
697                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
698                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
699
700                 /* Transport layer. */
701                 if (key->ip.proto == NEXTHDR_TCP) {
702                         if (tcphdr_ok(skb)) {
703                                 struct tcphdr *tcp = tcp_hdr(skb);
704                                 key->tp.src = tcp->source;
705                                 key->tp.dst = tcp->dest;
706                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
707                         } else {
708                                 memset(&key->tp, 0, sizeof(key->tp));
709                         }
710                 } else if (key->ip.proto == NEXTHDR_UDP) {
711                         if (udphdr_ok(skb)) {
712                                 struct udphdr *udp = udp_hdr(skb);
713                                 key->tp.src = udp->source;
714                                 key->tp.dst = udp->dest;
715                         } else {
716                                 memset(&key->tp, 0, sizeof(key->tp));
717                         }
718                 } else if (key->ip.proto == NEXTHDR_SCTP) {
719                         if (sctphdr_ok(skb)) {
720                                 struct sctphdr *sctp = sctp_hdr(skb);
721                                 key->tp.src = sctp->source;
722                                 key->tp.dst = sctp->dest;
723                         } else {
724                                 memset(&key->tp, 0, sizeof(key->tp));
725                         }
726                 } else if (key->ip.proto == NEXTHDR_ICMP) {
727                         if (icmp6hdr_ok(skb)) {
728                                 error = parse_icmpv6(skb, key, nh_len);
729                                 if (error)
730                                         return error;
731                         } else {
732                                 memset(&key->tp, 0, sizeof(key->tp));
733                         }
734                 }
735         } else if (key->eth.type == htons(ETH_P_NSH)) {
736                 error = parse_nsh(skb, key);
737                 if (error)
738                         return error;
739         }
740         return 0;
741 }
742
743 /**
744  * key_extract - extracts a flow key from an Ethernet frame.
745  * @skb: sk_buff that contains the frame, with skb->data pointing to the
746  * Ethernet header
747  * @key: output flow key
748  *
749  * The caller must ensure that skb->len >= ETH_HLEN.
750  *
751  * Returns 0 if successful, otherwise a negative errno value.
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 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
769 {
770         struct ethhdr *eth;
771
772         /* Flags are always used as part of stats */
773         key->tp.flags = 0;
774
775         skb_reset_mac_header(skb);
776
777         /* Link layer. */
778         clear_vlan(key);
779         if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
780                 if (unlikely(eth_type_vlan(skb->protocol)))
781                         return -EINVAL;
782
783                 skb_reset_network_header(skb);
784                 key->eth.type = skb->protocol;
785         } else {
786                 eth = eth_hdr(skb);
787                 ether_addr_copy(key->eth.src, eth->h_source);
788                 ether_addr_copy(key->eth.dst, eth->h_dest);
789
790                 __skb_pull(skb, 2 * ETH_ALEN);
791                 /* We are going to push all headers that we pull, so no need to
792                  * update skb->csum here.
793                  */
794
795                 if (unlikely(parse_vlan(skb, key)))
796                         return -ENOMEM;
797
798                 key->eth.type = parse_ethertype(skb);
799                 if (unlikely(key->eth.type == htons(0)))
800                         return -ENOMEM;
801
802                 /* Multiple tagged packets need to retain TPID to satisfy
803                  * skb_vlan_pop(), which will later shift the ethertype into
804                  * skb->protocol.
805                  */
806                 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
807                         skb->protocol = key->eth.cvlan.tpid;
808                 else
809                         skb->protocol = key->eth.type;
810
811                 skb_reset_network_header(skb);
812                 __skb_push(skb, skb->data - skb_mac_header(skb));
813         }
814
815         skb_reset_mac_len(skb);
816
817         /* Fill out L3/L4 key info, if any */
818         return key_extract_l3l4(skb, key);
819 }
820
821 /* In the case of conntrack fragment handling it expects L3 headers,
822  * add a helper.
823  */
824 int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
825 {
826         return key_extract_l3l4(skb, key);
827 }
828
829 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
830 {
831         int res;
832
833         res = key_extract(skb, key);
834         if (!res)
835                 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
836
837         return res;
838 }
839
840 static int key_extract_mac_proto(struct sk_buff *skb)
841 {
842         switch (skb->dev->type) {
843         case ARPHRD_ETHER:
844                 return MAC_PROTO_ETHERNET;
845         case ARPHRD_NONE:
846                 if (skb->protocol == htons(ETH_P_TEB))
847                         return MAC_PROTO_ETHERNET;
848                 return MAC_PROTO_NONE;
849         }
850         WARN_ON_ONCE(1);
851         return -EINVAL;
852 }
853
854 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
855                          struct sk_buff *skb, struct sw_flow_key *key)
856 {
857 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
858         struct tc_skb_ext *tc_ext;
859 #endif
860         int res, err;
861
862         /* Extract metadata from packet. */
863         if (tun_info) {
864                 key->tun_proto = ip_tunnel_info_af(tun_info);
865                 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
866
867                 if (tun_info->options_len) {
868                         BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
869                                                    8)) - 1
870                                         > sizeof(key->tun_opts));
871
872                         ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
873                                                 tun_info);
874                         key->tun_opts_len = tun_info->options_len;
875                 } else {
876                         key->tun_opts_len = 0;
877                 }
878         } else  {
879                 key->tun_proto = 0;
880                 key->tun_opts_len = 0;
881                 memset(&key->tun_key, 0, sizeof(key->tun_key));
882         }
883
884         key->phy.priority = skb->priority;
885         key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
886         key->phy.skb_mark = skb->mark;
887         key->ovs_flow_hash = 0;
888         res = key_extract_mac_proto(skb);
889         if (res < 0)
890                 return res;
891         key->mac_proto = res;
892
893 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
894         if (static_branch_unlikely(&tc_recirc_sharing_support)) {
895                 tc_ext = skb_ext_find(skb, TC_SKB_EXT);
896                 key->recirc_id = tc_ext ? tc_ext->chain : 0;
897                 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0;
898         } else {
899                 key->recirc_id = 0;
900         }
901 #else
902         key->recirc_id = 0;
903 #endif
904
905         err = key_extract(skb, key);
906         if (!err)
907                 ovs_ct_fill_key(skb, key);   /* Must be after key_extract(). */
908         return err;
909 }
910
911 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
912                                    struct sk_buff *skb,
913                                    struct sw_flow_key *key, bool log)
914 {
915         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
916         u64 attrs = 0;
917         int err;
918
919         err = parse_flow_nlattrs(attr, a, &attrs, log);
920         if (err)
921                 return -EINVAL;
922
923         /* Extract metadata from netlink attributes. */
924         err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
925         if (err)
926                 return err;
927
928         /* key_extract assumes that skb->protocol is set-up for
929          * layer 3 packets which is the case for other callers,
930          * in particular packets received from the network stack.
931          * Here the correct value can be set from the metadata
932          * extracted above.
933          * For L2 packet key eth type would be zero. skb protocol
934          * would be set to correct value later during key-extact.
935          */
936
937         skb->protocol = key->eth.type;
938         err = key_extract(skb, key);
939         if (err)
940                 return err;
941
942         /* Check that we have conntrack original direction tuple metadata only
943          * for packets for which it makes sense.  Otherwise the key may be
944          * corrupted due to overlapping key fields.
945          */
946         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
947             key->eth.type != htons(ETH_P_IP))
948                 return -EINVAL;
949         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
950             (key->eth.type != htons(ETH_P_IPV6) ||
951              sw_flow_key_is_nd(key)))
952                 return -EINVAL;
953
954         return 0;
955 }