xref: /openbmc/linux/net/openvswitch/flow.c (revision 0da85d1e)
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 
53 u64 ovs_flow_used_time(unsigned long flow_jiffies)
54 {
55 	struct timespec cur_ts;
56 	u64 cur_ms, idle_ms;
57 
58 	ktime_get_ts(&cur_ts);
59 	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
60 	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
61 		 cur_ts.tv_nsec / NSEC_PER_MSEC;
62 
63 	return cur_ms - idle_ms;
64 }
65 
66 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
67 
68 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
69 			   const struct sk_buff *skb)
70 {
71 	struct flow_stats *stats;
72 	int node = numa_node_id();
73 	int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
74 
75 	stats = rcu_dereference(flow->stats[node]);
76 
77 	/* Check if already have node-specific stats. */
78 	if (likely(stats)) {
79 		spin_lock(&stats->lock);
80 		/* Mark if we write on the pre-allocated stats. */
81 		if (node == 0 && unlikely(flow->stats_last_writer != node))
82 			flow->stats_last_writer = node;
83 	} else {
84 		stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
85 		spin_lock(&stats->lock);
86 
87 		/* If the current NUMA-node is the only writer on the
88 		 * pre-allocated stats keep using them.
89 		 */
90 		if (unlikely(flow->stats_last_writer != node)) {
91 			/* A previous locker may have already allocated the
92 			 * stats, so we need to check again.  If node-specific
93 			 * stats were already allocated, we update the pre-
94 			 * allocated stats as we have already locked them.
95 			 */
96 			if (likely(flow->stats_last_writer != NUMA_NO_NODE)
97 			    && likely(!rcu_access_pointer(flow->stats[node]))) {
98 				/* Try to allocate node-specific stats. */
99 				struct flow_stats *new_stats;
100 
101 				new_stats =
102 					kmem_cache_alloc_node(flow_stats_cache,
103 							      GFP_NOWAIT |
104 							      __GFP_THISNODE |
105 							      __GFP_NOWARN |
106 							      __GFP_NOMEMALLOC,
107 							      node);
108 				if (likely(new_stats)) {
109 					new_stats->used = jiffies;
110 					new_stats->packet_count = 1;
111 					new_stats->byte_count = len;
112 					new_stats->tcp_flags = tcp_flags;
113 					spin_lock_init(&new_stats->lock);
114 
115 					rcu_assign_pointer(flow->stats[node],
116 							   new_stats);
117 					goto unlock;
118 				}
119 			}
120 			flow->stats_last_writer = node;
121 		}
122 	}
123 
124 	stats->used = jiffies;
125 	stats->packet_count++;
126 	stats->byte_count += len;
127 	stats->tcp_flags |= tcp_flags;
128 unlock:
129 	spin_unlock(&stats->lock);
130 }
131 
132 /* Must be called with rcu_read_lock or ovs_mutex. */
133 void ovs_flow_stats_get(const struct sw_flow *flow,
134 			struct ovs_flow_stats *ovs_stats,
135 			unsigned long *used, __be16 *tcp_flags)
136 {
137 	int node;
138 
139 	*used = 0;
140 	*tcp_flags = 0;
141 	memset(ovs_stats, 0, sizeof(*ovs_stats));
142 
143 	for_each_node(node) {
144 		struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[node]);
145 
146 		if (stats) {
147 			/* Local CPU may write on non-local stats, so we must
148 			 * block bottom-halves here.
149 			 */
150 			spin_lock_bh(&stats->lock);
151 			if (!*used || time_after(stats->used, *used))
152 				*used = stats->used;
153 			*tcp_flags |= stats->tcp_flags;
154 			ovs_stats->n_packets += stats->packet_count;
155 			ovs_stats->n_bytes += stats->byte_count;
156 			spin_unlock_bh(&stats->lock);
157 		}
158 	}
159 }
160 
161 /* Called with ovs_mutex. */
162 void ovs_flow_stats_clear(struct sw_flow *flow)
163 {
164 	int node;
165 
166 	for_each_node(node) {
167 		struct flow_stats *stats = ovsl_dereference(flow->stats[node]);
168 
169 		if (stats) {
170 			spin_lock_bh(&stats->lock);
171 			stats->used = 0;
172 			stats->packet_count = 0;
173 			stats->byte_count = 0;
174 			stats->tcp_flags = 0;
175 			spin_unlock_bh(&stats->lock);
176 		}
177 	}
178 }
179 
180 static int check_header(struct sk_buff *skb, int len)
181 {
182 	if (unlikely(skb->len < len))
183 		return -EINVAL;
184 	if (unlikely(!pskb_may_pull(skb, len)))
185 		return -ENOMEM;
186 	return 0;
187 }
188 
189 static bool arphdr_ok(struct sk_buff *skb)
190 {
191 	return pskb_may_pull(skb, skb_network_offset(skb) +
192 				  sizeof(struct arp_eth_header));
193 }
194 
195 static int check_iphdr(struct sk_buff *skb)
196 {
197 	unsigned int nh_ofs = skb_network_offset(skb);
198 	unsigned int ip_len;
199 	int err;
200 
201 	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
202 	if (unlikely(err))
203 		return err;
204 
205 	ip_len = ip_hdrlen(skb);
206 	if (unlikely(ip_len < sizeof(struct iphdr) ||
207 		     skb->len < nh_ofs + ip_len))
208 		return -EINVAL;
209 
210 	skb_set_transport_header(skb, nh_ofs + ip_len);
211 	return 0;
212 }
213 
214 static bool tcphdr_ok(struct sk_buff *skb)
215 {
216 	int th_ofs = skb_transport_offset(skb);
217 	int tcp_len;
218 
219 	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
220 		return false;
221 
222 	tcp_len = tcp_hdrlen(skb);
223 	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
224 		     skb->len < th_ofs + tcp_len))
225 		return false;
226 
227 	return true;
228 }
229 
230 static bool udphdr_ok(struct sk_buff *skb)
231 {
232 	return pskb_may_pull(skb, skb_transport_offset(skb) +
233 				  sizeof(struct udphdr));
234 }
235 
236 static bool sctphdr_ok(struct sk_buff *skb)
237 {
238 	return pskb_may_pull(skb, skb_transport_offset(skb) +
239 				  sizeof(struct sctphdr));
240 }
241 
242 static bool icmphdr_ok(struct sk_buff *skb)
243 {
244 	return pskb_may_pull(skb, skb_transport_offset(skb) +
245 				  sizeof(struct icmphdr));
246 }
247 
248 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
249 {
250 	unsigned int nh_ofs = skb_network_offset(skb);
251 	unsigned int nh_len;
252 	int payload_ofs;
253 	struct ipv6hdr *nh;
254 	uint8_t nexthdr;
255 	__be16 frag_off;
256 	int err;
257 
258 	err = check_header(skb, nh_ofs + sizeof(*nh));
259 	if (unlikely(err))
260 		return err;
261 
262 	nh = ipv6_hdr(skb);
263 	nexthdr = nh->nexthdr;
264 	payload_ofs = (u8 *)(nh + 1) - skb->data;
265 
266 	key->ip.proto = NEXTHDR_NONE;
267 	key->ip.tos = ipv6_get_dsfield(nh);
268 	key->ip.ttl = nh->hop_limit;
269 	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
270 	key->ipv6.addr.src = nh->saddr;
271 	key->ipv6.addr.dst = nh->daddr;
272 
273 	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
274 	if (unlikely(payload_ofs < 0))
275 		return -EINVAL;
276 
277 	if (frag_off) {
278 		if (frag_off & htons(~0x7))
279 			key->ip.frag = OVS_FRAG_TYPE_LATER;
280 		else
281 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
282 	} else {
283 		key->ip.frag = OVS_FRAG_TYPE_NONE;
284 	}
285 
286 	nh_len = payload_ofs - nh_ofs;
287 	skb_set_transport_header(skb, nh_ofs + nh_len);
288 	key->ip.proto = nexthdr;
289 	return nh_len;
290 }
291 
292 static bool icmp6hdr_ok(struct sk_buff *skb)
293 {
294 	return pskb_may_pull(skb, skb_transport_offset(skb) +
295 				  sizeof(struct icmp6hdr));
296 }
297 
298 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
299 {
300 	struct qtag_prefix {
301 		__be16 eth_type; /* ETH_P_8021Q */
302 		__be16 tci;
303 	};
304 	struct qtag_prefix *qp;
305 
306 	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
307 		return 0;
308 
309 	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
310 					 sizeof(__be16))))
311 		return -ENOMEM;
312 
313 	qp = (struct qtag_prefix *) skb->data;
314 	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
315 	__skb_pull(skb, sizeof(struct qtag_prefix));
316 
317 	return 0;
318 }
319 
320 static __be16 parse_ethertype(struct sk_buff *skb)
321 {
322 	struct llc_snap_hdr {
323 		u8  dsap;  /* Always 0xAA */
324 		u8  ssap;  /* Always 0xAA */
325 		u8  ctrl;
326 		u8  oui[3];
327 		__be16 ethertype;
328 	};
329 	struct llc_snap_hdr *llc;
330 	__be16 proto;
331 
332 	proto = *(__be16 *) skb->data;
333 	__skb_pull(skb, sizeof(__be16));
334 
335 	if (ntohs(proto) >= ETH_P_802_3_MIN)
336 		return proto;
337 
338 	if (skb->len < sizeof(struct llc_snap_hdr))
339 		return htons(ETH_P_802_2);
340 
341 	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
342 		return htons(0);
343 
344 	llc = (struct llc_snap_hdr *) skb->data;
345 	if (llc->dsap != LLC_SAP_SNAP ||
346 	    llc->ssap != LLC_SAP_SNAP ||
347 	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
348 		return htons(ETH_P_802_2);
349 
350 	__skb_pull(skb, sizeof(struct llc_snap_hdr));
351 
352 	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
353 		return llc->ethertype;
354 
355 	return htons(ETH_P_802_2);
356 }
357 
358 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
359 			int nh_len)
360 {
361 	struct icmp6hdr *icmp = icmp6_hdr(skb);
362 
363 	/* The ICMPv6 type and code fields use the 16-bit transport port
364 	 * fields, so we need to store them in 16-bit network byte order.
365 	 */
366 	key->tp.src = htons(icmp->icmp6_type);
367 	key->tp.dst = htons(icmp->icmp6_code);
368 	memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
369 
370 	if (icmp->icmp6_code == 0 &&
371 	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
372 	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
373 		int icmp_len = skb->len - skb_transport_offset(skb);
374 		struct nd_msg *nd;
375 		int offset;
376 
377 		/* In order to process neighbor discovery options, we need the
378 		 * entire packet.
379 		 */
380 		if (unlikely(icmp_len < sizeof(*nd)))
381 			return 0;
382 
383 		if (unlikely(skb_linearize(skb)))
384 			return -ENOMEM;
385 
386 		nd = (struct nd_msg *)skb_transport_header(skb);
387 		key->ipv6.nd.target = nd->target;
388 
389 		icmp_len -= sizeof(*nd);
390 		offset = 0;
391 		while (icmp_len >= 8) {
392 			struct nd_opt_hdr *nd_opt =
393 				 (struct nd_opt_hdr *)(nd->opt + offset);
394 			int opt_len = nd_opt->nd_opt_len * 8;
395 
396 			if (unlikely(!opt_len || opt_len > icmp_len))
397 				return 0;
398 
399 			/* Store the link layer address if the appropriate
400 			 * option is provided.  It is considered an error if
401 			 * the same link layer option is specified twice.
402 			 */
403 			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
404 			    && opt_len == 8) {
405 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
406 					goto invalid;
407 				ether_addr_copy(key->ipv6.nd.sll,
408 						&nd->opt[offset+sizeof(*nd_opt)]);
409 			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
410 				   && opt_len == 8) {
411 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
412 					goto invalid;
413 				ether_addr_copy(key->ipv6.nd.tll,
414 						&nd->opt[offset+sizeof(*nd_opt)]);
415 			}
416 
417 			icmp_len -= opt_len;
418 			offset += opt_len;
419 		}
420 	}
421 
422 	return 0;
423 
424 invalid:
425 	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
426 	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
427 	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
428 
429 	return 0;
430 }
431 
432 /**
433  * key_extract - extracts a flow key from an Ethernet frame.
434  * @skb: sk_buff that contains the frame, with skb->data pointing to the
435  * Ethernet header
436  * @key: output flow key
437  *
438  * The caller must ensure that skb->len >= ETH_HLEN.
439  *
440  * Returns 0 if successful, otherwise a negative errno value.
441  *
442  * Initializes @skb header pointers as follows:
443  *
444  *    - skb->mac_header: the Ethernet header.
445  *
446  *    - skb->network_header: just past the Ethernet header, or just past the
447  *      VLAN header, to the first byte of the Ethernet payload.
448  *
449  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
450  *      on output, then just past the IP header, if one is present and
451  *      of a correct length, otherwise the same as skb->network_header.
452  *      For other key->eth.type values it is left untouched.
453  */
454 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
455 {
456 	int error;
457 	struct ethhdr *eth;
458 
459 	/* Flags are always used as part of stats */
460 	key->tp.flags = 0;
461 
462 	skb_reset_mac_header(skb);
463 
464 	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
465 	 * header in the linear data area.
466 	 */
467 	eth = eth_hdr(skb);
468 	ether_addr_copy(key->eth.src, eth->h_source);
469 	ether_addr_copy(key->eth.dst, eth->h_dest);
470 
471 	__skb_pull(skb, 2 * ETH_ALEN);
472 	/* We are going to push all headers that we pull, so no need to
473 	 * update skb->csum here.
474 	 */
475 
476 	key->eth.tci = 0;
477 	if (skb_vlan_tag_present(skb))
478 		key->eth.tci = htons(skb->vlan_tci);
479 	else if (eth->h_proto == htons(ETH_P_8021Q))
480 		if (unlikely(parse_vlan(skb, key)))
481 			return -ENOMEM;
482 
483 	key->eth.type = parse_ethertype(skb);
484 	if (unlikely(key->eth.type == htons(0)))
485 		return -ENOMEM;
486 
487 	skb_reset_network_header(skb);
488 	skb_reset_mac_len(skb);
489 	__skb_push(skb, skb->data - skb_mac_header(skb));
490 
491 	/* Network layer. */
492 	if (key->eth.type == htons(ETH_P_IP)) {
493 		struct iphdr *nh;
494 		__be16 offset;
495 
496 		error = check_iphdr(skb);
497 		if (unlikely(error)) {
498 			memset(&key->ip, 0, sizeof(key->ip));
499 			memset(&key->ipv4, 0, sizeof(key->ipv4));
500 			if (error == -EINVAL) {
501 				skb->transport_header = skb->network_header;
502 				error = 0;
503 			}
504 			return error;
505 		}
506 
507 		nh = ip_hdr(skb);
508 		key->ipv4.addr.src = nh->saddr;
509 		key->ipv4.addr.dst = nh->daddr;
510 
511 		key->ip.proto = nh->protocol;
512 		key->ip.tos = nh->tos;
513 		key->ip.ttl = nh->ttl;
514 
515 		offset = nh->frag_off & htons(IP_OFFSET);
516 		if (offset) {
517 			key->ip.frag = OVS_FRAG_TYPE_LATER;
518 			return 0;
519 		}
520 		if (nh->frag_off & htons(IP_MF) ||
521 			skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
522 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
523 		else
524 			key->ip.frag = OVS_FRAG_TYPE_NONE;
525 
526 		/* Transport layer. */
527 		if (key->ip.proto == IPPROTO_TCP) {
528 			if (tcphdr_ok(skb)) {
529 				struct tcphdr *tcp = tcp_hdr(skb);
530 				key->tp.src = tcp->source;
531 				key->tp.dst = tcp->dest;
532 				key->tp.flags = TCP_FLAGS_BE16(tcp);
533 			} else {
534 				memset(&key->tp, 0, sizeof(key->tp));
535 			}
536 
537 		} else if (key->ip.proto == IPPROTO_UDP) {
538 			if (udphdr_ok(skb)) {
539 				struct udphdr *udp = udp_hdr(skb);
540 				key->tp.src = udp->source;
541 				key->tp.dst = udp->dest;
542 			} else {
543 				memset(&key->tp, 0, sizeof(key->tp));
544 			}
545 		} else if (key->ip.proto == IPPROTO_SCTP) {
546 			if (sctphdr_ok(skb)) {
547 				struct sctphdr *sctp = sctp_hdr(skb);
548 				key->tp.src = sctp->source;
549 				key->tp.dst = sctp->dest;
550 			} else {
551 				memset(&key->tp, 0, sizeof(key->tp));
552 			}
553 		} else if (key->ip.proto == IPPROTO_ICMP) {
554 			if (icmphdr_ok(skb)) {
555 				struct icmphdr *icmp = icmp_hdr(skb);
556 				/* The ICMP type and code fields use the 16-bit
557 				 * transport port fields, so we need to store
558 				 * them in 16-bit network byte order. */
559 				key->tp.src = htons(icmp->type);
560 				key->tp.dst = htons(icmp->code);
561 			} else {
562 				memset(&key->tp, 0, sizeof(key->tp));
563 			}
564 		}
565 
566 	} else if (key->eth.type == htons(ETH_P_ARP) ||
567 		   key->eth.type == htons(ETH_P_RARP)) {
568 		struct arp_eth_header *arp;
569 		bool arp_available = arphdr_ok(skb);
570 
571 		arp = (struct arp_eth_header *)skb_network_header(skb);
572 
573 		if (arp_available &&
574 		    arp->ar_hrd == htons(ARPHRD_ETHER) &&
575 		    arp->ar_pro == htons(ETH_P_IP) &&
576 		    arp->ar_hln == ETH_ALEN &&
577 		    arp->ar_pln == 4) {
578 
579 			/* We only match on the lower 8 bits of the opcode. */
580 			if (ntohs(arp->ar_op) <= 0xff)
581 				key->ip.proto = ntohs(arp->ar_op);
582 			else
583 				key->ip.proto = 0;
584 
585 			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
586 			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
587 			ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
588 			ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
589 		} else {
590 			memset(&key->ip, 0, sizeof(key->ip));
591 			memset(&key->ipv4, 0, sizeof(key->ipv4));
592 		}
593 	} else if (eth_p_mpls(key->eth.type)) {
594 		size_t stack_len = MPLS_HLEN;
595 
596 		/* In the presence of an MPLS label stack the end of the L2
597 		 * header and the beginning of the L3 header differ.
598 		 *
599 		 * Advance network_header to the beginning of the L3
600 		 * header. mac_len corresponds to the end of the L2 header.
601 		 */
602 		while (1) {
603 			__be32 lse;
604 
605 			error = check_header(skb, skb->mac_len + stack_len);
606 			if (unlikely(error))
607 				return 0;
608 
609 			memcpy(&lse, skb_network_header(skb), MPLS_HLEN);
610 
611 			if (stack_len == MPLS_HLEN)
612 				memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
613 
614 			skb_set_network_header(skb, skb->mac_len + stack_len);
615 			if (lse & htonl(MPLS_LS_S_MASK))
616 				break;
617 
618 			stack_len += MPLS_HLEN;
619 		}
620 	} else if (key->eth.type == htons(ETH_P_IPV6)) {
621 		int nh_len;             /* IPv6 Header + Extensions */
622 
623 		nh_len = parse_ipv6hdr(skb, key);
624 		if (unlikely(nh_len < 0)) {
625 			memset(&key->ip, 0, sizeof(key->ip));
626 			memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
627 			if (nh_len == -EINVAL) {
628 				skb->transport_header = skb->network_header;
629 				error = 0;
630 			} else {
631 				error = nh_len;
632 			}
633 			return error;
634 		}
635 
636 		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
637 			return 0;
638 		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
639 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
640 
641 		/* Transport layer. */
642 		if (key->ip.proto == NEXTHDR_TCP) {
643 			if (tcphdr_ok(skb)) {
644 				struct tcphdr *tcp = tcp_hdr(skb);
645 				key->tp.src = tcp->source;
646 				key->tp.dst = tcp->dest;
647 				key->tp.flags = TCP_FLAGS_BE16(tcp);
648 			} else {
649 				memset(&key->tp, 0, sizeof(key->tp));
650 			}
651 		} else if (key->ip.proto == NEXTHDR_UDP) {
652 			if (udphdr_ok(skb)) {
653 				struct udphdr *udp = udp_hdr(skb);
654 				key->tp.src = udp->source;
655 				key->tp.dst = udp->dest;
656 			} else {
657 				memset(&key->tp, 0, sizeof(key->tp));
658 			}
659 		} else if (key->ip.proto == NEXTHDR_SCTP) {
660 			if (sctphdr_ok(skb)) {
661 				struct sctphdr *sctp = sctp_hdr(skb);
662 				key->tp.src = sctp->source;
663 				key->tp.dst = sctp->dest;
664 			} else {
665 				memset(&key->tp, 0, sizeof(key->tp));
666 			}
667 		} else if (key->ip.proto == NEXTHDR_ICMP) {
668 			if (icmp6hdr_ok(skb)) {
669 				error = parse_icmpv6(skb, key, nh_len);
670 				if (error)
671 					return error;
672 			} else {
673 				memset(&key->tp, 0, sizeof(key->tp));
674 			}
675 		}
676 	}
677 	return 0;
678 }
679 
680 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
681 {
682 	return key_extract(skb, key);
683 }
684 
685 int ovs_flow_key_extract(const struct ovs_tunnel_info *tun_info,
686 			 struct sk_buff *skb, struct sw_flow_key *key)
687 {
688 	/* Extract metadata from packet. */
689 	if (tun_info) {
690 		memcpy(&key->tun_key, &tun_info->tunnel, sizeof(key->tun_key));
691 
692 		if (tun_info->options) {
693 			BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
694 						   8)) - 1
695 					> sizeof(key->tun_opts));
696 			memcpy(TUN_METADATA_OPTS(key, tun_info->options_len),
697 			       tun_info->options, tun_info->options_len);
698 			key->tun_opts_len = tun_info->options_len;
699 		} else {
700 			key->tun_opts_len = 0;
701 		}
702 	} else  {
703 		key->tun_opts_len = 0;
704 		memset(&key->tun_key, 0, sizeof(key->tun_key));
705 	}
706 
707 	key->phy.priority = skb->priority;
708 	key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
709 	key->phy.skb_mark = skb->mark;
710 	key->ovs_flow_hash = 0;
711 	key->recirc_id = 0;
712 
713 	return key_extract(skb, key);
714 }
715 
716 int ovs_flow_key_extract_userspace(const struct nlattr *attr,
717 				   struct sk_buff *skb,
718 				   struct sw_flow_key *key, bool log)
719 {
720 	int err;
721 
722 	memset(key, 0, OVS_SW_FLOW_KEY_METADATA_SIZE);
723 
724 	/* Extract metadata from netlink attributes. */
725 	err = ovs_nla_get_flow_metadata(attr, key, log);
726 	if (err)
727 		return err;
728 
729 	return key_extract(skb, key);
730 }
731