xref: /openbmc/linux/net/openvswitch/flow.c (revision 21c721fd0b991b1871ea5dd517be1b5375c5f8f7)
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/if_arp.h>
33 #include <linux/ip.h>
34 #include <linux/ipv6.h>
35 #include <linux/mpls.h>
36 #include <linux/sctp.h>
37 #include <linux/smp.h>
38 #include <linux/tcp.h>
39 #include <linux/udp.h>
40 #include <linux/icmp.h>
41 #include <linux/icmpv6.h>
42 #include <linux/rculist.h>
43 #include <net/ip.h>
44 #include <net/ip_tunnels.h>
45 #include <net/ipv6.h>
46 #include <net/mpls.h>
47 #include <net/ndisc.h>
48 
49 #include "datapath.h"
50 #include "flow.h"
51 #include "flow_netlink.h"
52 #include "conntrack.h"
53 
54 u64 ovs_flow_used_time(unsigned long flow_jiffies)
55 {
56 	struct timespec cur_ts;
57 	u64 cur_ms, idle_ms;
58 
59 	ktime_get_ts(&cur_ts);
60 	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
61 	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
62 		 cur_ts.tv_nsec / NSEC_PER_MSEC;
63 
64 	return cur_ms - idle_ms;
65 }
66 
67 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
68 
69 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
70 			   const struct sk_buff *skb)
71 {
72 	struct flow_stats *stats;
73 	int node = numa_node_id();
74 	int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
75 
76 	stats = rcu_dereference(flow->stats[node]);
77 
78 	/* Check if already have node-specific stats. */
79 	if (likely(stats)) {
80 		spin_lock(&stats->lock);
81 		/* Mark if we write on the pre-allocated stats. */
82 		if (node == 0 && unlikely(flow->stats_last_writer != node))
83 			flow->stats_last_writer = node;
84 	} else {
85 		stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
86 		spin_lock(&stats->lock);
87 
88 		/* If the current NUMA-node is the only writer on the
89 		 * pre-allocated stats keep using them.
90 		 */
91 		if (unlikely(flow->stats_last_writer != node)) {
92 			/* A previous locker may have already allocated the
93 			 * stats, so we need to check again.  If node-specific
94 			 * stats were already allocated, we update the pre-
95 			 * allocated stats as we have already locked them.
96 			 */
97 			if (likely(flow->stats_last_writer != NUMA_NO_NODE)
98 			    && likely(!rcu_access_pointer(flow->stats[node]))) {
99 				/* Try to allocate node-specific stats. */
100 				struct flow_stats *new_stats;
101 
102 				new_stats =
103 					kmem_cache_alloc_node(flow_stats_cache,
104 							      GFP_NOWAIT |
105 							      __GFP_THISNODE |
106 							      __GFP_NOWARN |
107 							      __GFP_NOMEMALLOC,
108 							      node);
109 				if (likely(new_stats)) {
110 					new_stats->used = jiffies;
111 					new_stats->packet_count = 1;
112 					new_stats->byte_count = len;
113 					new_stats->tcp_flags = tcp_flags;
114 					spin_lock_init(&new_stats->lock);
115 
116 					rcu_assign_pointer(flow->stats[node],
117 							   new_stats);
118 					goto unlock;
119 				}
120 			}
121 			flow->stats_last_writer = node;
122 		}
123 	}
124 
125 	stats->used = jiffies;
126 	stats->packet_count++;
127 	stats->byte_count += len;
128 	stats->tcp_flags |= tcp_flags;
129 unlock:
130 	spin_unlock(&stats->lock);
131 }
132 
133 /* Must be called with rcu_read_lock or ovs_mutex. */
134 void ovs_flow_stats_get(const struct sw_flow *flow,
135 			struct ovs_flow_stats *ovs_stats,
136 			unsigned long *used, __be16 *tcp_flags)
137 {
138 	int node;
139 
140 	*used = 0;
141 	*tcp_flags = 0;
142 	memset(ovs_stats, 0, sizeof(*ovs_stats));
143 
144 	for_each_node(node) {
145 		struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[node]);
146 
147 		if (stats) {
148 			/* Local CPU may write on non-local stats, so we must
149 			 * block bottom-halves here.
150 			 */
151 			spin_lock_bh(&stats->lock);
152 			if (!*used || time_after(stats->used, *used))
153 				*used = stats->used;
154 			*tcp_flags |= stats->tcp_flags;
155 			ovs_stats->n_packets += stats->packet_count;
156 			ovs_stats->n_bytes += stats->byte_count;
157 			spin_unlock_bh(&stats->lock);
158 		}
159 	}
160 }
161 
162 /* Called with ovs_mutex. */
163 void ovs_flow_stats_clear(struct sw_flow *flow)
164 {
165 	int node;
166 
167 	for_each_node(node) {
168 		struct flow_stats *stats = ovsl_dereference(flow->stats[node]);
169 
170 		if (stats) {
171 			spin_lock_bh(&stats->lock);
172 			stats->used = 0;
173 			stats->packet_count = 0;
174 			stats->byte_count = 0;
175 			stats->tcp_flags = 0;
176 			spin_unlock_bh(&stats->lock);
177 		}
178 	}
179 }
180 
181 static int check_header(struct sk_buff *skb, int len)
182 {
183 	if (unlikely(skb->len < len))
184 		return -EINVAL;
185 	if (unlikely(!pskb_may_pull(skb, len)))
186 		return -ENOMEM;
187 	return 0;
188 }
189 
190 static bool arphdr_ok(struct sk_buff *skb)
191 {
192 	return pskb_may_pull(skb, skb_network_offset(skb) +
193 				  sizeof(struct arp_eth_header));
194 }
195 
196 static int check_iphdr(struct sk_buff *skb)
197 {
198 	unsigned int nh_ofs = skb_network_offset(skb);
199 	unsigned int ip_len;
200 	int err;
201 
202 	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
203 	if (unlikely(err))
204 		return err;
205 
206 	ip_len = ip_hdrlen(skb);
207 	if (unlikely(ip_len < sizeof(struct iphdr) ||
208 		     skb->len < nh_ofs + ip_len))
209 		return -EINVAL;
210 
211 	skb_set_transport_header(skb, nh_ofs + ip_len);
212 	return 0;
213 }
214 
215 static bool tcphdr_ok(struct sk_buff *skb)
216 {
217 	int th_ofs = skb_transport_offset(skb);
218 	int tcp_len;
219 
220 	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
221 		return false;
222 
223 	tcp_len = tcp_hdrlen(skb);
224 	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
225 		     skb->len < th_ofs + tcp_len))
226 		return false;
227 
228 	return true;
229 }
230 
231 static bool udphdr_ok(struct sk_buff *skb)
232 {
233 	return pskb_may_pull(skb, skb_transport_offset(skb) +
234 				  sizeof(struct udphdr));
235 }
236 
237 static bool sctphdr_ok(struct sk_buff *skb)
238 {
239 	return pskb_may_pull(skb, skb_transport_offset(skb) +
240 				  sizeof(struct sctphdr));
241 }
242 
243 static bool icmphdr_ok(struct sk_buff *skb)
244 {
245 	return pskb_may_pull(skb, skb_transport_offset(skb) +
246 				  sizeof(struct icmphdr));
247 }
248 
249 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
250 {
251 	unsigned int nh_ofs = skb_network_offset(skb);
252 	unsigned int nh_len;
253 	int payload_ofs;
254 	struct ipv6hdr *nh;
255 	uint8_t nexthdr;
256 	__be16 frag_off;
257 	int err;
258 
259 	err = check_header(skb, nh_ofs + sizeof(*nh));
260 	if (unlikely(err))
261 		return err;
262 
263 	nh = ipv6_hdr(skb);
264 	nexthdr = nh->nexthdr;
265 	payload_ofs = (u8 *)(nh + 1) - skb->data;
266 
267 	key->ip.proto = NEXTHDR_NONE;
268 	key->ip.tos = ipv6_get_dsfield(nh);
269 	key->ip.ttl = nh->hop_limit;
270 	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
271 	key->ipv6.addr.src = nh->saddr;
272 	key->ipv6.addr.dst = nh->daddr;
273 
274 	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
275 	if (unlikely(payload_ofs < 0))
276 		return -EINVAL;
277 
278 	if (frag_off) {
279 		if (frag_off & htons(~0x7))
280 			key->ip.frag = OVS_FRAG_TYPE_LATER;
281 		else
282 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
283 	} else {
284 		key->ip.frag = OVS_FRAG_TYPE_NONE;
285 	}
286 
287 	nh_len = payload_ofs - nh_ofs;
288 	skb_set_transport_header(skb, nh_ofs + nh_len);
289 	key->ip.proto = nexthdr;
290 	return nh_len;
291 }
292 
293 static bool icmp6hdr_ok(struct sk_buff *skb)
294 {
295 	return pskb_may_pull(skb, skb_transport_offset(skb) +
296 				  sizeof(struct icmp6hdr));
297 }
298 
299 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
300 {
301 	struct qtag_prefix {
302 		__be16 eth_type; /* ETH_P_8021Q */
303 		__be16 tci;
304 	};
305 	struct qtag_prefix *qp;
306 
307 	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
308 		return 0;
309 
310 	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
311 					 sizeof(__be16))))
312 		return -ENOMEM;
313 
314 	qp = (struct qtag_prefix *) skb->data;
315 	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
316 	__skb_pull(skb, sizeof(struct qtag_prefix));
317 
318 	return 0;
319 }
320 
321 static __be16 parse_ethertype(struct sk_buff *skb)
322 {
323 	struct llc_snap_hdr {
324 		u8  dsap;  /* Always 0xAA */
325 		u8  ssap;  /* Always 0xAA */
326 		u8  ctrl;
327 		u8  oui[3];
328 		__be16 ethertype;
329 	};
330 	struct llc_snap_hdr *llc;
331 	__be16 proto;
332 
333 	proto = *(__be16 *) skb->data;
334 	__skb_pull(skb, sizeof(__be16));
335 
336 	if (eth_proto_is_802_3(proto))
337 		return proto;
338 
339 	if (skb->len < sizeof(struct llc_snap_hdr))
340 		return htons(ETH_P_802_2);
341 
342 	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
343 		return htons(0);
344 
345 	llc = (struct llc_snap_hdr *) skb->data;
346 	if (llc->dsap != LLC_SAP_SNAP ||
347 	    llc->ssap != LLC_SAP_SNAP ||
348 	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
349 		return htons(ETH_P_802_2);
350 
351 	__skb_pull(skb, sizeof(struct llc_snap_hdr));
352 
353 	if (eth_proto_is_802_3(llc->ethertype))
354 		return llc->ethertype;
355 
356 	return htons(ETH_P_802_2);
357 }
358 
359 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
360 			int nh_len)
361 {
362 	struct icmp6hdr *icmp = icmp6_hdr(skb);
363 
364 	/* The ICMPv6 type and code fields use the 16-bit transport port
365 	 * fields, so we need to store them in 16-bit network byte order.
366 	 */
367 	key->tp.src = htons(icmp->icmp6_type);
368 	key->tp.dst = htons(icmp->icmp6_code);
369 	memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
370 
371 	if (icmp->icmp6_code == 0 &&
372 	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
373 	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
374 		int icmp_len = skb->len - skb_transport_offset(skb);
375 		struct nd_msg *nd;
376 		int offset;
377 
378 		/* In order to process neighbor discovery options, we need the
379 		 * entire packet.
380 		 */
381 		if (unlikely(icmp_len < sizeof(*nd)))
382 			return 0;
383 
384 		if (unlikely(skb_linearize(skb)))
385 			return -ENOMEM;
386 
387 		nd = (struct nd_msg *)skb_transport_header(skb);
388 		key->ipv6.nd.target = nd->target;
389 
390 		icmp_len -= sizeof(*nd);
391 		offset = 0;
392 		while (icmp_len >= 8) {
393 			struct nd_opt_hdr *nd_opt =
394 				 (struct nd_opt_hdr *)(nd->opt + offset);
395 			int opt_len = nd_opt->nd_opt_len * 8;
396 
397 			if (unlikely(!opt_len || opt_len > icmp_len))
398 				return 0;
399 
400 			/* Store the link layer address if the appropriate
401 			 * option is provided.  It is considered an error if
402 			 * the same link layer option is specified twice.
403 			 */
404 			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
405 			    && opt_len == 8) {
406 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
407 					goto invalid;
408 				ether_addr_copy(key->ipv6.nd.sll,
409 						&nd->opt[offset+sizeof(*nd_opt)]);
410 			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
411 				   && opt_len == 8) {
412 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
413 					goto invalid;
414 				ether_addr_copy(key->ipv6.nd.tll,
415 						&nd->opt[offset+sizeof(*nd_opt)]);
416 			}
417 
418 			icmp_len -= opt_len;
419 			offset += opt_len;
420 		}
421 	}
422 
423 	return 0;
424 
425 invalid:
426 	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
427 	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
428 	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
429 
430 	return 0;
431 }
432 
433 /**
434  * key_extract - extracts a flow key from an Ethernet frame.
435  * @skb: sk_buff that contains the frame, with skb->data pointing to the
436  * Ethernet header
437  * @key: output flow key
438  *
439  * The caller must ensure that skb->len >= ETH_HLEN.
440  *
441  * Returns 0 if successful, otherwise a negative errno value.
442  *
443  * Initializes @skb header pointers as follows:
444  *
445  *    - skb->mac_header: the Ethernet header.
446  *
447  *    - skb->network_header: just past the Ethernet header, or just past the
448  *      VLAN header, to the first byte of the Ethernet payload.
449  *
450  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
451  *      on output, then just past the IP header, if one is present and
452  *      of a correct length, otherwise the same as skb->network_header.
453  *      For other key->eth.type values it is left untouched.
454  */
455 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
456 {
457 	int error;
458 	struct ethhdr *eth;
459 
460 	/* Flags are always used as part of stats */
461 	key->tp.flags = 0;
462 
463 	skb_reset_mac_header(skb);
464 
465 	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
466 	 * header in the linear data area.
467 	 */
468 	eth = eth_hdr(skb);
469 	ether_addr_copy(key->eth.src, eth->h_source);
470 	ether_addr_copy(key->eth.dst, eth->h_dest);
471 
472 	__skb_pull(skb, 2 * ETH_ALEN);
473 	/* We are going to push all headers that we pull, so no need to
474 	 * update skb->csum here.
475 	 */
476 
477 	key->eth.tci = 0;
478 	if (skb_vlan_tag_present(skb))
479 		key->eth.tci = htons(skb->vlan_tci);
480 	else if (eth->h_proto == htons(ETH_P_8021Q))
481 		if (unlikely(parse_vlan(skb, key)))
482 			return -ENOMEM;
483 
484 	key->eth.type = parse_ethertype(skb);
485 	if (unlikely(key->eth.type == htons(0)))
486 		return -ENOMEM;
487 
488 	skb_reset_network_header(skb);
489 	skb_reset_mac_len(skb);
490 	__skb_push(skb, skb->data - skb_mac_header(skb));
491 
492 	/* Network layer. */
493 	if (key->eth.type == htons(ETH_P_IP)) {
494 		struct iphdr *nh;
495 		__be16 offset;
496 
497 		error = check_iphdr(skb);
498 		if (unlikely(error)) {
499 			memset(&key->ip, 0, sizeof(key->ip));
500 			memset(&key->ipv4, 0, sizeof(key->ipv4));
501 			if (error == -EINVAL) {
502 				skb->transport_header = skb->network_header;
503 				error = 0;
504 			}
505 			return error;
506 		}
507 
508 		nh = ip_hdr(skb);
509 		key->ipv4.addr.src = nh->saddr;
510 		key->ipv4.addr.dst = nh->daddr;
511 
512 		key->ip.proto = nh->protocol;
513 		key->ip.tos = nh->tos;
514 		key->ip.ttl = nh->ttl;
515 
516 		offset = nh->frag_off & htons(IP_OFFSET);
517 		if (offset) {
518 			key->ip.frag = OVS_FRAG_TYPE_LATER;
519 			return 0;
520 		}
521 		if (nh->frag_off & htons(IP_MF) ||
522 			skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
523 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
524 		else
525 			key->ip.frag = OVS_FRAG_TYPE_NONE;
526 
527 		/* Transport layer. */
528 		if (key->ip.proto == IPPROTO_TCP) {
529 			if (tcphdr_ok(skb)) {
530 				struct tcphdr *tcp = tcp_hdr(skb);
531 				key->tp.src = tcp->source;
532 				key->tp.dst = tcp->dest;
533 				key->tp.flags = TCP_FLAGS_BE16(tcp);
534 			} else {
535 				memset(&key->tp, 0, sizeof(key->tp));
536 			}
537 
538 		} else if (key->ip.proto == IPPROTO_UDP) {
539 			if (udphdr_ok(skb)) {
540 				struct udphdr *udp = udp_hdr(skb);
541 				key->tp.src = udp->source;
542 				key->tp.dst = udp->dest;
543 			} else {
544 				memset(&key->tp, 0, sizeof(key->tp));
545 			}
546 		} else if (key->ip.proto == IPPROTO_SCTP) {
547 			if (sctphdr_ok(skb)) {
548 				struct sctphdr *sctp = sctp_hdr(skb);
549 				key->tp.src = sctp->source;
550 				key->tp.dst = sctp->dest;
551 			} else {
552 				memset(&key->tp, 0, sizeof(key->tp));
553 			}
554 		} else if (key->ip.proto == IPPROTO_ICMP) {
555 			if (icmphdr_ok(skb)) {
556 				struct icmphdr *icmp = icmp_hdr(skb);
557 				/* The ICMP type and code fields use the 16-bit
558 				 * transport port fields, so we need to store
559 				 * them in 16-bit network byte order. */
560 				key->tp.src = htons(icmp->type);
561 				key->tp.dst = htons(icmp->code);
562 			} else {
563 				memset(&key->tp, 0, sizeof(key->tp));
564 			}
565 		}
566 
567 	} else if (key->eth.type == htons(ETH_P_ARP) ||
568 		   key->eth.type == htons(ETH_P_RARP)) {
569 		struct arp_eth_header *arp;
570 		bool arp_available = arphdr_ok(skb);
571 
572 		arp = (struct arp_eth_header *)skb_network_header(skb);
573 
574 		if (arp_available &&
575 		    arp->ar_hrd == htons(ARPHRD_ETHER) &&
576 		    arp->ar_pro == htons(ETH_P_IP) &&
577 		    arp->ar_hln == ETH_ALEN &&
578 		    arp->ar_pln == 4) {
579 
580 			/* We only match on the lower 8 bits of the opcode. */
581 			if (ntohs(arp->ar_op) <= 0xff)
582 				key->ip.proto = ntohs(arp->ar_op);
583 			else
584 				key->ip.proto = 0;
585 
586 			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
587 			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
588 			ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
589 			ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
590 		} else {
591 			memset(&key->ip, 0, sizeof(key->ip));
592 			memset(&key->ipv4, 0, sizeof(key->ipv4));
593 		}
594 	} else if (eth_p_mpls(key->eth.type)) {
595 		size_t stack_len = MPLS_HLEN;
596 
597 		/* In the presence of an MPLS label stack the end of the L2
598 		 * header and the beginning of the L3 header differ.
599 		 *
600 		 * Advance network_header to the beginning of the L3
601 		 * header. mac_len corresponds to the end of the L2 header.
602 		 */
603 		while (1) {
604 			__be32 lse;
605 
606 			error = check_header(skb, skb->mac_len + stack_len);
607 			if (unlikely(error))
608 				return 0;
609 
610 			memcpy(&lse, skb_network_header(skb), MPLS_HLEN);
611 
612 			if (stack_len == MPLS_HLEN)
613 				memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
614 
615 			skb_set_network_header(skb, skb->mac_len + stack_len);
616 			if (lse & htonl(MPLS_LS_S_MASK))
617 				break;
618 
619 			stack_len += MPLS_HLEN;
620 		}
621 	} else if (key->eth.type == htons(ETH_P_IPV6)) {
622 		int nh_len;             /* IPv6 Header + Extensions */
623 
624 		nh_len = parse_ipv6hdr(skb, key);
625 		if (unlikely(nh_len < 0)) {
626 			memset(&key->ip, 0, sizeof(key->ip));
627 			memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
628 			if (nh_len == -EINVAL) {
629 				skb->transport_header = skb->network_header;
630 				error = 0;
631 			} else {
632 				error = nh_len;
633 			}
634 			return error;
635 		}
636 
637 		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
638 			return 0;
639 		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
640 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
641 
642 		/* Transport layer. */
643 		if (key->ip.proto == NEXTHDR_TCP) {
644 			if (tcphdr_ok(skb)) {
645 				struct tcphdr *tcp = tcp_hdr(skb);
646 				key->tp.src = tcp->source;
647 				key->tp.dst = tcp->dest;
648 				key->tp.flags = TCP_FLAGS_BE16(tcp);
649 			} else {
650 				memset(&key->tp, 0, sizeof(key->tp));
651 			}
652 		} else if (key->ip.proto == NEXTHDR_UDP) {
653 			if (udphdr_ok(skb)) {
654 				struct udphdr *udp = udp_hdr(skb);
655 				key->tp.src = udp->source;
656 				key->tp.dst = udp->dest;
657 			} else {
658 				memset(&key->tp, 0, sizeof(key->tp));
659 			}
660 		} else if (key->ip.proto == NEXTHDR_SCTP) {
661 			if (sctphdr_ok(skb)) {
662 				struct sctphdr *sctp = sctp_hdr(skb);
663 				key->tp.src = sctp->source;
664 				key->tp.dst = sctp->dest;
665 			} else {
666 				memset(&key->tp, 0, sizeof(key->tp));
667 			}
668 		} else if (key->ip.proto == NEXTHDR_ICMP) {
669 			if (icmp6hdr_ok(skb)) {
670 				error = parse_icmpv6(skb, key, nh_len);
671 				if (error)
672 					return error;
673 			} else {
674 				memset(&key->tp, 0, sizeof(key->tp));
675 			}
676 		}
677 	}
678 	return 0;
679 }
680 
681 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
682 {
683 	return key_extract(skb, key);
684 }
685 
686 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
687 			 struct sk_buff *skb, struct sw_flow_key *key)
688 {
689 	/* Extract metadata from packet. */
690 	if (tun_info) {
691 		memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
692 
693 		if (tun_info->options) {
694 			BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
695 						   8)) - 1
696 					> sizeof(key->tun_opts));
697 			memcpy(TUN_METADATA_OPTS(key, tun_info->options_len),
698 			       tun_info->options, tun_info->options_len);
699 			key->tun_opts_len = tun_info->options_len;
700 		} else {
701 			key->tun_opts_len = 0;
702 		}
703 	} else  {
704 		key->tun_opts_len = 0;
705 		memset(&key->tun_key, 0, sizeof(key->tun_key));
706 	}
707 
708 	key->phy.priority = skb->priority;
709 	key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
710 	key->phy.skb_mark = skb->mark;
711 	ovs_ct_fill_key(skb, key);
712 	key->ovs_flow_hash = 0;
713 	key->recirc_id = 0;
714 
715 	return key_extract(skb, key);
716 }
717 
718 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
719 				   struct sk_buff *skb,
720 				   struct sw_flow_key *key, bool log)
721 {
722 	int err;
723 
724 	memset(key, 0, OVS_SW_FLOW_KEY_METADATA_SIZE);
725 
726 	/* Extract metadata from netlink attributes. */
727 	err = ovs_nla_get_flow_metadata(net, attr, key, log);
728 	if (err)
729 		return err;
730 
731 	return key_extract(skb, key);
732 }
733