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Linux/net/openvswitch/flow.c

Version: ~ [ linux-5.12-rc1 ] ~ [ linux-5.11.2 ] ~ [ linux-5.10.19 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.101 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.177 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.222 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.258 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.258 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
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  1 /*
  2  * Copyright (c) 2007-2014 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 <linux/uaccess.h>
 20 #include <linux/netdevice.h>
 21 #include <linux/etherdevice.h>
 22 #include <linux/if_ether.h>
 23 #include <linux/if_vlan.h>
 24 #include <net/llc_pdu.h>
 25 #include <linux/kernel.h>
 26 #include <linux/jhash.h>
 27 #include <linux/jiffies.h>
 28 #include <linux/llc.h>
 29 #include <linux/module.h>
 30 #include <linux/in.h>
 31 #include <linux/rcupdate.h>
 32 #include <linux/cpumask.h>
 33 #include <linux/if_arp.h>
 34 #include <linux/ip.h>
 35 #include <linux/ipv6.h>
 36 #include <linux/mpls.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/mpls.h>
 48 #include <net/ndisc.h>
 49 
 50 #include "conntrack.h"
 51 #include "datapath.h"
 52 #include "flow.h"
 53 #include "flow_netlink.h"
 54 #include "vport.h"
 55 
 56 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 57 {
 58         struct timespec cur_ts;
 59         u64 cur_ms, idle_ms;
 60 
 61         ktime_get_ts(&cur_ts);
 62         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 63         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 64                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 65 
 66         return cur_ms - idle_ms;
 67 }
 68 
 69 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
 70 
 71 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
 72                            const struct sk_buff *skb)
 73 {
 74         struct flow_stats *stats;
 75         int node = numa_node_id();
 76         int cpu = smp_processor_id();
 77         int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
 78 
 79         stats = rcu_dereference(flow->stats[cpu]);
 80 
 81         /* Check if already have CPU-specific stats. */
 82         if (likely(stats)) {
 83                 spin_lock(&stats->lock);
 84                 /* Mark if we write on the pre-allocated stats. */
 85                 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
 86                         flow->stats_last_writer = cpu;
 87         } else {
 88                 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
 89                 spin_lock(&stats->lock);
 90 
 91                 /* If the current CPU is the only writer on the
 92                  * pre-allocated stats keep using them.
 93                  */
 94                 if (unlikely(flow->stats_last_writer != cpu)) {
 95                         /* A previous locker may have already allocated the
 96                          * stats, so we need to check again.  If CPU-specific
 97                          * stats were already allocated, we update the pre-
 98                          * allocated stats as we have already locked them.
 99                          */
100                         if (likely(flow->stats_last_writer != -1) &&
101                             likely(!rcu_access_pointer(flow->stats[cpu]))) {
102                                 /* Try to allocate CPU-specific stats. */
103                                 struct flow_stats *new_stats;
104 
105                                 new_stats =
106                                         kmem_cache_alloc_node(flow_stats_cache,
107                                                               GFP_NOWAIT |
108                                                               __GFP_THISNODE |
109                                                               __GFP_NOWARN |
110                                                               __GFP_NOMEMALLOC,
111                                                               node);
112                                 if (likely(new_stats)) {
113                                         new_stats->used = jiffies;
114                                         new_stats->packet_count = 1;
115                                         new_stats->byte_count = len;
116                                         new_stats->tcp_flags = tcp_flags;
117                                         spin_lock_init(&new_stats->lock);
118 
119                                         rcu_assign_pointer(flow->stats[cpu],
120                                                            new_stats);
121                                         goto unlock;
122                                 }
123                         }
124                         flow->stats_last_writer = cpu;
125                 }
126         }
127 
128         stats->used = jiffies;
129         stats->packet_count++;
130         stats->byte_count += len;
131         stats->tcp_flags |= tcp_flags;
132 unlock:
133         spin_unlock(&stats->lock);
134 }
135 
136 /* Must be called with rcu_read_lock or ovs_mutex. */
137 void ovs_flow_stats_get(const struct sw_flow *flow,
138                         struct ovs_flow_stats *ovs_stats,
139                         unsigned long *used, __be16 *tcp_flags)
140 {
141         int cpu;
142 
143         *used = 0;
144         *tcp_flags = 0;
145         memset(ovs_stats, 0, sizeof(*ovs_stats));
146 
147         /* We open code this to make sure cpu 0 is always considered */
148         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
149                 struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
150 
151                 if (stats) {
152                         /* Local CPU may write on non-local stats, so we must
153                          * block bottom-halves here.
154                          */
155                         spin_lock_bh(&stats->lock);
156                         if (!*used || time_after(stats->used, *used))
157                                 *used = stats->used;
158                         *tcp_flags |= stats->tcp_flags;
159                         ovs_stats->n_packets += stats->packet_count;
160                         ovs_stats->n_bytes += stats->byte_count;
161                         spin_unlock_bh(&stats->lock);
162                 }
163         }
164 }
165 
166 /* Called with ovs_mutex. */
167 void ovs_flow_stats_clear(struct sw_flow *flow)
168 {
169         int cpu;
170 
171         /* We open code this to make sure cpu 0 is always considered */
172         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
173                 struct flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
174 
175                 if (stats) {
176                         spin_lock_bh(&stats->lock);
177                         stats->used = 0;
178                         stats->packet_count = 0;
179                         stats->byte_count = 0;
180                         stats->tcp_flags = 0;
181                         spin_unlock_bh(&stats->lock);
182                 }
183         }
184 }
185 
186 static int check_header(struct sk_buff *skb, int len)
187 {
188         if (unlikely(skb->len < len))
189                 return -EINVAL;
190         if (unlikely(!pskb_may_pull(skb, len)))
191                 return -ENOMEM;
192         return 0;
193 }
194 
195 static bool arphdr_ok(struct sk_buff *skb)
196 {
197         return pskb_may_pull(skb, skb_network_offset(skb) +
198                                   sizeof(struct arp_eth_header));
199 }
200 
201 static int check_iphdr(struct sk_buff *skb)
202 {
203         unsigned int nh_ofs = skb_network_offset(skb);
204         unsigned int ip_len;
205         int err;
206 
207         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
208         if (unlikely(err))
209                 return err;
210 
211         ip_len = ip_hdrlen(skb);
212         if (unlikely(ip_len < sizeof(struct iphdr) ||
213                      skb->len < nh_ofs + ip_len))
214                 return -EINVAL;
215 
216         skb_set_transport_header(skb, nh_ofs + ip_len);
217         return 0;
218 }
219 
220 static bool tcphdr_ok(struct sk_buff *skb)
221 {
222         int th_ofs = skb_transport_offset(skb);
223         int tcp_len;
224 
225         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
226                 return false;
227 
228         tcp_len = tcp_hdrlen(skb);
229         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
230                      skb->len < th_ofs + tcp_len))
231                 return false;
232 
233         return true;
234 }
235 
236 static bool udphdr_ok(struct sk_buff *skb)
237 {
238         return pskb_may_pull(skb, skb_transport_offset(skb) +
239                                   sizeof(struct udphdr));
240 }
241 
242 static bool sctphdr_ok(struct sk_buff *skb)
243 {
244         return pskb_may_pull(skb, skb_transport_offset(skb) +
245                                   sizeof(struct sctphdr));
246 }
247 
248 static bool icmphdr_ok(struct sk_buff *skb)
249 {
250         return pskb_may_pull(skb, skb_transport_offset(skb) +
251                                   sizeof(struct icmphdr));
252 }
253 
254 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
255 {
256         unsigned int nh_ofs = skb_network_offset(skb);
257         unsigned int nh_len;
258         int payload_ofs;
259         struct ipv6hdr *nh;
260         uint8_t nexthdr;
261         __be16 frag_off;
262         int err;
263 
264         err = check_header(skb, nh_ofs + sizeof(*nh));
265         if (unlikely(err))
266                 return err;
267 
268         nh = ipv6_hdr(skb);
269         nexthdr = nh->nexthdr;
270         payload_ofs = (u8 *)(nh + 1) - skb->data;
271 
272         key->ip.proto = NEXTHDR_NONE;
273         key->ip.tos = ipv6_get_dsfield(nh);
274         key->ip.ttl = nh->hop_limit;
275         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
276         key->ipv6.addr.src = nh->saddr;
277         key->ipv6.addr.dst = nh->daddr;
278 
279         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
280 
281         if (frag_off) {
282                 if (frag_off & htons(~0x7))
283                         key->ip.frag = OVS_FRAG_TYPE_LATER;
284                 else
285                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
286         } else {
287                 key->ip.frag = OVS_FRAG_TYPE_NONE;
288         }
289 
290         /* Delayed handling of error in ipv6_skip_exthdr() as it
291          * always sets frag_off to a valid value which may be
292          * used to set key->ip.frag above.
293          */
294         if (unlikely(payload_ofs < 0))
295                 return -EPROTO;
296 
297         nh_len = payload_ofs - nh_ofs;
298         skb_set_transport_header(skb, nh_ofs + nh_len);
299         key->ip.proto = nexthdr;
300         return nh_len;
301 }
302 
303 static bool icmp6hdr_ok(struct sk_buff *skb)
304 {
305         return pskb_may_pull(skb, skb_transport_offset(skb) +
306                                   sizeof(struct icmp6hdr));
307 }
308 
309 /**
310  * Parse vlan tag from vlan header.
311  * Returns ERROR on memory error.
312  * Returns 0 if it encounters a non-vlan or incomplete packet.
313  * Returns 1 after successfully parsing vlan tag.
314  */
315 static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
316                           bool untag_vlan)
317 {
318         struct vlan_head *vh = (struct vlan_head *)skb->data;
319 
320         if (likely(!eth_type_vlan(vh->tpid)))
321                 return 0;
322 
323         if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
324                 return 0;
325 
326         if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
327                                  sizeof(__be16))))
328                 return -ENOMEM;
329 
330         vh = (struct vlan_head *)skb->data;
331         key_vh->tci = vh->tci | htons(VLAN_TAG_PRESENT);
332         key_vh->tpid = vh->tpid;
333 
334         if (unlikely(untag_vlan)) {
335                 int offset = skb->data - skb_mac_header(skb);
336                 u16 tci;
337                 int err;
338 
339                 __skb_push(skb, offset);
340                 err = __skb_vlan_pop(skb, &tci);
341                 __skb_pull(skb, offset);
342                 if (err)
343                         return err;
344                 __vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
345         } else {
346                 __skb_pull(skb, sizeof(struct vlan_head));
347         }
348         return 1;
349 }
350 
351 static void clear_vlan(struct sw_flow_key *key)
352 {
353         key->eth.vlan.tci = 0;
354         key->eth.vlan.tpid = 0;
355         key->eth.cvlan.tci = 0;
356         key->eth.cvlan.tpid = 0;
357 }
358 
359 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
360 {
361         int res;
362 
363         if (skb_vlan_tag_present(skb)) {
364                 key->eth.vlan.tci = htons(skb->vlan_tci);
365                 key->eth.vlan.tpid = skb->vlan_proto;
366         } else {
367                 /* Parse outer vlan tag in the non-accelerated case. */
368                 res = parse_vlan_tag(skb, &key->eth.vlan, true);
369                 if (res <= 0)
370                         return res;
371         }
372 
373         /* Parse inner vlan tag. */
374         res = parse_vlan_tag(skb, &key->eth.cvlan, false);
375         if (res <= 0)
376                 return res;
377 
378         return 0;
379 }
380 
381 static __be16 parse_ethertype(struct sk_buff *skb)
382 {
383         struct llc_snap_hdr {
384                 u8  dsap;  /* Always 0xAA */
385                 u8  ssap;  /* Always 0xAA */
386                 u8  ctrl;
387                 u8  oui[3];
388                 __be16 ethertype;
389         };
390         struct llc_snap_hdr *llc;
391         __be16 proto;
392 
393         proto = *(__be16 *) skb->data;
394         __skb_pull(skb, sizeof(__be16));
395 
396         if (eth_proto_is_802_3(proto))
397                 return proto;
398 
399         if (skb->len < sizeof(struct llc_snap_hdr))
400                 return htons(ETH_P_802_2);
401 
402         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
403                 return htons(0);
404 
405         llc = (struct llc_snap_hdr *) skb->data;
406         if (llc->dsap != LLC_SAP_SNAP ||
407             llc->ssap != LLC_SAP_SNAP ||
408             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
409                 return htons(ETH_P_802_2);
410 
411         __skb_pull(skb, sizeof(struct llc_snap_hdr));
412 
413         if (eth_proto_is_802_3(llc->ethertype))
414                 return llc->ethertype;
415 
416         return htons(ETH_P_802_2);
417 }
418 
419 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
420                         int nh_len)
421 {
422         struct icmp6hdr *icmp = icmp6_hdr(skb);
423 
424         /* The ICMPv6 type and code fields use the 16-bit transport port
425          * fields, so we need to store them in 16-bit network byte order.
426          */
427         key->tp.src = htons(icmp->icmp6_type);
428         key->tp.dst = htons(icmp->icmp6_code);
429         memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
430 
431         if (icmp->icmp6_code == 0 &&
432             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
433              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
434                 int icmp_len = skb->len - skb_transport_offset(skb);
435                 struct nd_msg *nd;
436                 int offset;
437 
438                 /* In order to process neighbor discovery options, we need the
439                  * entire packet.
440                  */
441                 if (unlikely(icmp_len < sizeof(*nd)))
442                         return 0;
443 
444                 if (unlikely(skb_linearize(skb)))
445                         return -ENOMEM;
446 
447                 nd = (struct nd_msg *)skb_transport_header(skb);
448                 key->ipv6.nd.target = nd->target;
449 
450                 icmp_len -= sizeof(*nd);
451                 offset = 0;
452                 while (icmp_len >= 8) {
453                         struct nd_opt_hdr *nd_opt =
454                                  (struct nd_opt_hdr *)(nd->opt + offset);
455                         int opt_len = nd_opt->nd_opt_len * 8;
456 
457                         if (unlikely(!opt_len || opt_len > icmp_len))
458                                 return 0;
459 
460                         /* Store the link layer address if the appropriate
461                          * option is provided.  It is considered an error if
462                          * the same link layer option is specified twice.
463                          */
464                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
465                             && opt_len == 8) {
466                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
467                                         goto invalid;
468                                 ether_addr_copy(key->ipv6.nd.sll,
469                                                 &nd->opt[offset+sizeof(*nd_opt)]);
470                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
471                                    && opt_len == 8) {
472                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
473                                         goto invalid;
474                                 ether_addr_copy(key->ipv6.nd.tll,
475                                                 &nd->opt[offset+sizeof(*nd_opt)]);
476                         }
477 
478                         icmp_len -= opt_len;
479                         offset += opt_len;
480                 }
481         }
482 
483         return 0;
484 
485 invalid:
486         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
487         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
488         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
489 
490         return 0;
491 }
492 
493 /**
494  * key_extract - extracts a flow key from an Ethernet frame.
495  * @skb: sk_buff that contains the frame, with skb->data pointing to the
496  * Ethernet header
497  * @key: output flow key
498  *
499  * The caller must ensure that skb->len >= ETH_HLEN.
500  *
501  * Returns 0 if successful, otherwise a negative errno value.
502  *
503  * Initializes @skb header fields as follows:
504  *
505  *    - skb->mac_header: the L2 header.
506  *
507  *    - skb->network_header: just past the L2 header, or just past the
508  *      VLAN header, to the first byte of the L2 payload.
509  *
510  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
511  *      on output, then just past the IP header, if one is present and
512  *      of a correct length, otherwise the same as skb->network_header.
513  *      For other key->eth.type values it is left untouched.
514  *
515  *    - skb->protocol: the type of the data starting at skb->network_header.
516  *      Equals to key->eth.type.
517  */
518 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
519 {
520         int error;
521         struct ethhdr *eth;
522 
523         /* Flags are always used as part of stats */
524         key->tp.flags = 0;
525 
526         skb_reset_mac_header(skb);
527 
528         /* Link layer. */
529         clear_vlan(key);
530         if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
531                 if (unlikely(eth_type_vlan(skb->protocol)))
532                         return -EINVAL;
533 
534                 skb_reset_network_header(skb);
535         } else {
536                 eth = eth_hdr(skb);
537                 ether_addr_copy(key->eth.src, eth->h_source);
538                 ether_addr_copy(key->eth.dst, eth->h_dest);
539 
540                 __skb_pull(skb, 2 * ETH_ALEN);
541                 /* We are going to push all headers that we pull, so no need to
542                 * update skb->csum here.
543                 */
544 
545                 if (unlikely(parse_vlan(skb, key)))
546                         return -ENOMEM;
547 
548                 skb->protocol = parse_ethertype(skb);
549                 if (unlikely(skb->protocol == htons(0)))
550                         return -ENOMEM;
551 
552                 skb_reset_network_header(skb);
553                 __skb_push(skb, skb->data - skb_mac_header(skb));
554         }
555         skb_reset_mac_len(skb);
556         key->eth.type = skb->protocol;
557 
558         /* Network layer. */
559         if (key->eth.type == htons(ETH_P_IP)) {
560                 struct iphdr *nh;
561                 __be16 offset;
562 
563                 error = check_iphdr(skb);
564                 if (unlikely(error)) {
565                         memset(&key->ip, 0, sizeof(key->ip));
566                         memset(&key->ipv4, 0, sizeof(key->ipv4));
567                         if (error == -EINVAL) {
568                                 skb->transport_header = skb->network_header;
569                                 error = 0;
570                         }
571                         return error;
572                 }
573 
574                 nh = ip_hdr(skb);
575                 key->ipv4.addr.src = nh->saddr;
576                 key->ipv4.addr.dst = nh->daddr;
577 
578                 key->ip.proto = nh->protocol;
579                 key->ip.tos = nh->tos;
580                 key->ip.ttl = nh->ttl;
581 
582                 offset = nh->frag_off & htons(IP_OFFSET);
583                 if (offset) {
584                         key->ip.frag = OVS_FRAG_TYPE_LATER;
585                         return 0;
586                 }
587                 if (nh->frag_off & htons(IP_MF) ||
588                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
589                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
590                 else
591                         key->ip.frag = OVS_FRAG_TYPE_NONE;
592 
593                 /* Transport layer. */
594                 if (key->ip.proto == IPPROTO_TCP) {
595                         if (tcphdr_ok(skb)) {
596                                 struct tcphdr *tcp = tcp_hdr(skb);
597                                 key->tp.src = tcp->source;
598                                 key->tp.dst = tcp->dest;
599                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
600                         } else {
601                                 memset(&key->tp, 0, sizeof(key->tp));
602                         }
603 
604                 } else if (key->ip.proto == IPPROTO_UDP) {
605                         if (udphdr_ok(skb)) {
606                                 struct udphdr *udp = udp_hdr(skb);
607                                 key->tp.src = udp->source;
608                                 key->tp.dst = udp->dest;
609                         } else {
610                                 memset(&key->tp, 0, sizeof(key->tp));
611                         }
612                 } else if (key->ip.proto == IPPROTO_SCTP) {
613                         if (sctphdr_ok(skb)) {
614                                 struct sctphdr *sctp = sctp_hdr(skb);
615                                 key->tp.src = sctp->source;
616                                 key->tp.dst = sctp->dest;
617                         } else {
618                                 memset(&key->tp, 0, sizeof(key->tp));
619                         }
620                 } else if (key->ip.proto == IPPROTO_ICMP) {
621                         if (icmphdr_ok(skb)) {
622                                 struct icmphdr *icmp = icmp_hdr(skb);
623                                 /* The ICMP type and code fields use the 16-bit
624                                  * transport port fields, so we need to store
625                                  * them in 16-bit network byte order. */
626                                 key->tp.src = htons(icmp->type);
627                                 key->tp.dst = htons(icmp->code);
628                         } else {
629                                 memset(&key->tp, 0, sizeof(key->tp));
630                         }
631                 }
632 
633         } else if (key->eth.type == htons(ETH_P_ARP) ||
634                    key->eth.type == htons(ETH_P_RARP)) {
635                 struct arp_eth_header *arp;
636                 bool arp_available = arphdr_ok(skb);
637 
638                 arp = (struct arp_eth_header *)skb_network_header(skb);
639 
640                 if (arp_available &&
641                     arp->ar_hrd == htons(ARPHRD_ETHER) &&
642                     arp->ar_pro == htons(ETH_P_IP) &&
643                     arp->ar_hln == ETH_ALEN &&
644                     arp->ar_pln == 4) {
645 
646                         /* We only match on the lower 8 bits of the opcode. */
647                         if (ntohs(arp->ar_op) <= 0xff)
648                                 key->ip.proto = ntohs(arp->ar_op);
649                         else
650                                 key->ip.proto = 0;
651 
652                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
653                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
654                         ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
655                         ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
656                 } else {
657                         memset(&key->ip, 0, sizeof(key->ip));
658                         memset(&key->ipv4, 0, sizeof(key->ipv4));
659                 }
660         } else if (eth_p_mpls(key->eth.type)) {
661                 size_t stack_len = MPLS_HLEN;
662 
663                 skb_set_inner_network_header(skb, skb->mac_len);
664                 while (1) {
665                         __be32 lse;
666 
667                         error = check_header(skb, skb->mac_len + stack_len);
668                         if (unlikely(error))
669                                 return 0;
670 
671                         memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
672 
673                         if (stack_len == MPLS_HLEN)
674                                 memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
675 
676                         skb_set_inner_network_header(skb, skb->mac_len + stack_len);
677                         if (lse & htonl(MPLS_LS_S_MASK))
678                                 break;
679 
680                         stack_len += MPLS_HLEN;
681                 }
682         } else if (key->eth.type == htons(ETH_P_IPV6)) {
683                 int nh_len;             /* IPv6 Header + Extensions */
684 
685                 nh_len = parse_ipv6hdr(skb, key);
686                 if (unlikely(nh_len < 0)) {
687                         switch (nh_len) {
688                         case -EINVAL:
689                                 memset(&key->ip, 0, sizeof(key->ip));
690                                 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
691                                 /* fall-through */
692                         case -EPROTO:
693                                 skb->transport_header = skb->network_header;
694                                 error = 0;
695                                 break;
696                         default:
697                                 error = nh_len;
698                         }
699                         return error;
700                 }
701 
702                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
703                         return 0;
704                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
705                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
706 
707                 /* Transport layer. */
708                 if (key->ip.proto == NEXTHDR_TCP) {
709                         if (tcphdr_ok(skb)) {
710                                 struct tcphdr *tcp = tcp_hdr(skb);
711                                 key->tp.src = tcp->source;
712                                 key->tp.dst = tcp->dest;
713                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
714                         } else {
715                                 memset(&key->tp, 0, sizeof(key->tp));
716                         }
717                 } else if (key->ip.proto == NEXTHDR_UDP) {
718                         if (udphdr_ok(skb)) {
719                                 struct udphdr *udp = udp_hdr(skb);
720                                 key->tp.src = udp->source;
721                                 key->tp.dst = udp->dest;
722                         } else {
723                                 memset(&key->tp, 0, sizeof(key->tp));
724                         }
725                 } else if (key->ip.proto == NEXTHDR_SCTP) {
726                         if (sctphdr_ok(skb)) {
727                                 struct sctphdr *sctp = sctp_hdr(skb);
728                                 key->tp.src = sctp->source;
729                                 key->tp.dst = sctp->dest;
730                         } else {
731                                 memset(&key->tp, 0, sizeof(key->tp));
732                         }
733                 } else if (key->ip.proto == NEXTHDR_ICMP) {
734                         if (icmp6hdr_ok(skb)) {
735                                 error = parse_icmpv6(skb, key, nh_len);
736                                 if (error)
737                                         return error;
738                         } else {
739                                 memset(&key->tp, 0, sizeof(key->tp));
740                         }
741                 }
742         }
743         return 0;
744 }
745 
746 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
747 {
748         int res;
749 
750         res = key_extract(skb, key);
751         if (!res)
752                 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
753 
754         return res;
755 }
756 
757 static int key_extract_mac_proto(struct sk_buff *skb)
758 {
759         switch (skb->dev->type) {
760         case ARPHRD_ETHER:
761                 return MAC_PROTO_ETHERNET;
762         case ARPHRD_NONE:
763                 if (skb->protocol == htons(ETH_P_TEB))
764                         return MAC_PROTO_ETHERNET;
765                 return MAC_PROTO_NONE;
766         }
767         WARN_ON_ONCE(1);
768         return -EINVAL;
769 }
770 
771 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
772                          struct sk_buff *skb, struct sw_flow_key *key)
773 {
774         int res, err;
775 
776         /* Extract metadata from packet. */
777         if (tun_info) {
778                 key->tun_proto = ip_tunnel_info_af(tun_info);
779                 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
780 
781                 if (tun_info->options_len) {
782                         BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
783                                                    8)) - 1
784                                         > sizeof(key->tun_opts));
785 
786                         ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
787                                                 tun_info);
788                         key->tun_opts_len = tun_info->options_len;
789                 } else {
790                         key->tun_opts_len = 0;
791                 }
792         } else  {
793                 key->tun_proto = 0;
794                 key->tun_opts_len = 0;
795                 memset(&key->tun_key, 0, sizeof(key->tun_key));
796         }
797 
798         key->phy.priority = skb->priority;
799         key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
800         key->phy.skb_mark = skb->mark;
801         key->ovs_flow_hash = 0;
802         res = key_extract_mac_proto(skb);
803         if (res < 0)
804                 return res;
805         key->mac_proto = res;
806         key->recirc_id = 0;
807 
808         err = key_extract(skb, key);
809         if (!err)
810                 ovs_ct_fill_key(skb, key);   /* Must be after key_extract(). */
811         return err;
812 }
813 
814 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
815                                    struct sk_buff *skb,
816                                    struct sw_flow_key *key, bool log)
817 {
818         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
819         u64 attrs = 0;
820         int err;
821 
822         err = parse_flow_nlattrs(attr, a, &attrs, log);
823         if (err)
824                 return -EINVAL;
825 
826         /* Extract metadata from netlink attributes. */
827         err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
828         if (err)
829                 return err;
830 
831         /* key_extract assumes that skb->protocol is set-up for
832          * layer 3 packets which is the case for other callers,
833          * in particular packets received from the network stack.
834          * Here the correct value can be set from the metadata
835          * extracted above.
836          * For L2 packet key eth type would be zero. skb protocol
837          * would be set to correct value later during key-extact.
838          */
839 
840         skb->protocol = key->eth.type;
841         err = key_extract(skb, key);
842         if (err)
843                 return err;
844 
845         /* Check that we have conntrack original direction tuple metadata only
846          * for packets for which it makes sense.  Otherwise the key may be
847          * corrupted due to overlapping key fields.
848          */
849         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
850             key->eth.type != htons(ETH_P_IP))
851                 return -EINVAL;
852         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
853             (key->eth.type != htons(ETH_P_IPV6) ||
854              sw_flow_key_is_nd(key)))
855                 return -EINVAL;
856 
857         return 0;
858 }
859 

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