xref: /openbmc/linux/net/openvswitch/flow.c (revision 7490ca1e)
1 /*
2  * Copyright (c) 2007-2011 Nicira Networks.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of version 2 of the GNU General Public
6  * License as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16  * 02110-1301, USA
17  */
18 
19 #include "flow.h"
20 #include "datapath.h"
21 #include <linux/uaccess.h>
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/if_ether.h>
25 #include <linux/if_vlan.h>
26 #include <net/llc_pdu.h>
27 #include <linux/kernel.h>
28 #include <linux/jhash.h>
29 #include <linux/jiffies.h>
30 #include <linux/llc.h>
31 #include <linux/module.h>
32 #include <linux/in.h>
33 #include <linux/rcupdate.h>
34 #include <linux/if_arp.h>
35 #include <linux/ip.h>
36 #include <linux/ipv6.h>
37 #include <linux/tcp.h>
38 #include <linux/udp.h>
39 #include <linux/icmp.h>
40 #include <linux/icmpv6.h>
41 #include <linux/rculist.h>
42 #include <net/ip.h>
43 #include <net/ipv6.h>
44 #include <net/ndisc.h>
45 
46 static struct kmem_cache *flow_cache;
47 
48 static int check_header(struct sk_buff *skb, int len)
49 {
50 	if (unlikely(skb->len < len))
51 		return -EINVAL;
52 	if (unlikely(!pskb_may_pull(skb, len)))
53 		return -ENOMEM;
54 	return 0;
55 }
56 
57 static bool arphdr_ok(struct sk_buff *skb)
58 {
59 	return pskb_may_pull(skb, skb_network_offset(skb) +
60 				  sizeof(struct arp_eth_header));
61 }
62 
63 static int check_iphdr(struct sk_buff *skb)
64 {
65 	unsigned int nh_ofs = skb_network_offset(skb);
66 	unsigned int ip_len;
67 	int err;
68 
69 	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
70 	if (unlikely(err))
71 		return err;
72 
73 	ip_len = ip_hdrlen(skb);
74 	if (unlikely(ip_len < sizeof(struct iphdr) ||
75 		     skb->len < nh_ofs + ip_len))
76 		return -EINVAL;
77 
78 	skb_set_transport_header(skb, nh_ofs + ip_len);
79 	return 0;
80 }
81 
82 static bool tcphdr_ok(struct sk_buff *skb)
83 {
84 	int th_ofs = skb_transport_offset(skb);
85 	int tcp_len;
86 
87 	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
88 		return false;
89 
90 	tcp_len = tcp_hdrlen(skb);
91 	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
92 		     skb->len < th_ofs + tcp_len))
93 		return false;
94 
95 	return true;
96 }
97 
98 static bool udphdr_ok(struct sk_buff *skb)
99 {
100 	return pskb_may_pull(skb, skb_transport_offset(skb) +
101 				  sizeof(struct udphdr));
102 }
103 
104 static bool icmphdr_ok(struct sk_buff *skb)
105 {
106 	return pskb_may_pull(skb, skb_transport_offset(skb) +
107 				  sizeof(struct icmphdr));
108 }
109 
110 u64 ovs_flow_used_time(unsigned long flow_jiffies)
111 {
112 	struct timespec cur_ts;
113 	u64 cur_ms, idle_ms;
114 
115 	ktime_get_ts(&cur_ts);
116 	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
117 	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
118 		 cur_ts.tv_nsec / NSEC_PER_MSEC;
119 
120 	return cur_ms - idle_ms;
121 }
122 
123 #define SW_FLOW_KEY_OFFSET(field)		\
124 	(offsetof(struct sw_flow_key, field) +	\
125 	 FIELD_SIZEOF(struct sw_flow_key, field))
126 
127 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
128 			 int *key_lenp)
129 {
130 	unsigned int nh_ofs = skb_network_offset(skb);
131 	unsigned int nh_len;
132 	int payload_ofs;
133 	struct ipv6hdr *nh;
134 	uint8_t nexthdr;
135 	__be16 frag_off;
136 	int err;
137 
138 	*key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
139 
140 	err = check_header(skb, nh_ofs + sizeof(*nh));
141 	if (unlikely(err))
142 		return err;
143 
144 	nh = ipv6_hdr(skb);
145 	nexthdr = nh->nexthdr;
146 	payload_ofs = (u8 *)(nh + 1) - skb->data;
147 
148 	key->ip.proto = NEXTHDR_NONE;
149 	key->ip.tos = ipv6_get_dsfield(nh);
150 	key->ip.ttl = nh->hop_limit;
151 	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
152 	key->ipv6.addr.src = nh->saddr;
153 	key->ipv6.addr.dst = nh->daddr;
154 
155 	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
156 	if (unlikely(payload_ofs < 0))
157 		return -EINVAL;
158 
159 	if (frag_off) {
160 		if (frag_off & htons(~0x7))
161 			key->ip.frag = OVS_FRAG_TYPE_LATER;
162 		else
163 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
164 	}
165 
166 	nh_len = payload_ofs - nh_ofs;
167 	skb_set_transport_header(skb, nh_ofs + nh_len);
168 	key->ip.proto = nexthdr;
169 	return nh_len;
170 }
171 
172 static bool icmp6hdr_ok(struct sk_buff *skb)
173 {
174 	return pskb_may_pull(skb, skb_transport_offset(skb) +
175 				  sizeof(struct icmp6hdr));
176 }
177 
178 #define TCP_FLAGS_OFFSET 13
179 #define TCP_FLAG_MASK 0x3f
180 
181 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
182 {
183 	u8 tcp_flags = 0;
184 
185 	if (flow->key.eth.type == htons(ETH_P_IP) &&
186 	    flow->key.ip.proto == IPPROTO_TCP) {
187 		u8 *tcp = (u8 *)tcp_hdr(skb);
188 		tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
189 	}
190 
191 	spin_lock(&flow->lock);
192 	flow->used = jiffies;
193 	flow->packet_count++;
194 	flow->byte_count += skb->len;
195 	flow->tcp_flags |= tcp_flags;
196 	spin_unlock(&flow->lock);
197 }
198 
199 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
200 {
201 	int actions_len = nla_len(actions);
202 	struct sw_flow_actions *sfa;
203 
204 	/* At least DP_MAX_PORTS actions are required to be able to flood a
205 	 * packet to every port.  Factor of 2 allows for setting VLAN tags,
206 	 * etc. */
207 	if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
208 		return ERR_PTR(-EINVAL);
209 
210 	sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
211 	if (!sfa)
212 		return ERR_PTR(-ENOMEM);
213 
214 	sfa->actions_len = actions_len;
215 	memcpy(sfa->actions, nla_data(actions), actions_len);
216 	return sfa;
217 }
218 
219 struct sw_flow *ovs_flow_alloc(void)
220 {
221 	struct sw_flow *flow;
222 
223 	flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
224 	if (!flow)
225 		return ERR_PTR(-ENOMEM);
226 
227 	spin_lock_init(&flow->lock);
228 	flow->sf_acts = NULL;
229 
230 	return flow;
231 }
232 
233 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
234 {
235 	hash = jhash_1word(hash, table->hash_seed);
236 	return flex_array_get(table->buckets,
237 				(hash & (table->n_buckets - 1)));
238 }
239 
240 static struct flex_array *alloc_buckets(unsigned int n_buckets)
241 {
242 	struct flex_array *buckets;
243 	int i, err;
244 
245 	buckets = flex_array_alloc(sizeof(struct hlist_head *),
246 				   n_buckets, GFP_KERNEL);
247 	if (!buckets)
248 		return NULL;
249 
250 	err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
251 	if (err) {
252 		flex_array_free(buckets);
253 		return NULL;
254 	}
255 
256 	for (i = 0; i < n_buckets; i++)
257 		INIT_HLIST_HEAD((struct hlist_head *)
258 					flex_array_get(buckets, i));
259 
260 	return buckets;
261 }
262 
263 static void free_buckets(struct flex_array *buckets)
264 {
265 	flex_array_free(buckets);
266 }
267 
268 struct flow_table *ovs_flow_tbl_alloc(int new_size)
269 {
270 	struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
271 
272 	if (!table)
273 		return NULL;
274 
275 	table->buckets = alloc_buckets(new_size);
276 
277 	if (!table->buckets) {
278 		kfree(table);
279 		return NULL;
280 	}
281 	table->n_buckets = new_size;
282 	table->count = 0;
283 	table->node_ver = 0;
284 	table->keep_flows = false;
285 	get_random_bytes(&table->hash_seed, sizeof(u32));
286 
287 	return table;
288 }
289 
290 void ovs_flow_tbl_destroy(struct flow_table *table)
291 {
292 	int i;
293 
294 	if (!table)
295 		return;
296 
297 	if (table->keep_flows)
298 		goto skip_flows;
299 
300 	for (i = 0; i < table->n_buckets; i++) {
301 		struct sw_flow *flow;
302 		struct hlist_head *head = flex_array_get(table->buckets, i);
303 		struct hlist_node *node, *n;
304 		int ver = table->node_ver;
305 
306 		hlist_for_each_entry_safe(flow, node, n, head, hash_node[ver]) {
307 			hlist_del_rcu(&flow->hash_node[ver]);
308 			ovs_flow_free(flow);
309 		}
310 	}
311 
312 skip_flows:
313 	free_buckets(table->buckets);
314 	kfree(table);
315 }
316 
317 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
318 {
319 	struct flow_table *table = container_of(rcu, struct flow_table, rcu);
320 
321 	ovs_flow_tbl_destroy(table);
322 }
323 
324 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
325 {
326 	if (!table)
327 		return;
328 
329 	call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
330 }
331 
332 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
333 {
334 	struct sw_flow *flow;
335 	struct hlist_head *head;
336 	struct hlist_node *n;
337 	int ver;
338 	int i;
339 
340 	ver = table->node_ver;
341 	while (*bucket < table->n_buckets) {
342 		i = 0;
343 		head = flex_array_get(table->buckets, *bucket);
344 		hlist_for_each_entry_rcu(flow, n, head, hash_node[ver]) {
345 			if (i < *last) {
346 				i++;
347 				continue;
348 			}
349 			*last = i + 1;
350 			return flow;
351 		}
352 		(*bucket)++;
353 		*last = 0;
354 	}
355 
356 	return NULL;
357 }
358 
359 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
360 {
361 	int old_ver;
362 	int i;
363 
364 	old_ver = old->node_ver;
365 	new->node_ver = !old_ver;
366 
367 	/* Insert in new table. */
368 	for (i = 0; i < old->n_buckets; i++) {
369 		struct sw_flow *flow;
370 		struct hlist_head *head;
371 		struct hlist_node *n;
372 
373 		head = flex_array_get(old->buckets, i);
374 
375 		hlist_for_each_entry(flow, n, head, hash_node[old_ver])
376 			ovs_flow_tbl_insert(new, flow);
377 	}
378 	old->keep_flows = true;
379 }
380 
381 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
382 {
383 	struct flow_table *new_table;
384 
385 	new_table = ovs_flow_tbl_alloc(n_buckets);
386 	if (!new_table)
387 		return ERR_PTR(-ENOMEM);
388 
389 	flow_table_copy_flows(table, new_table);
390 
391 	return new_table;
392 }
393 
394 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
395 {
396 	return __flow_tbl_rehash(table, table->n_buckets);
397 }
398 
399 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
400 {
401 	return __flow_tbl_rehash(table, table->n_buckets * 2);
402 }
403 
404 void ovs_flow_free(struct sw_flow *flow)
405 {
406 	if (unlikely(!flow))
407 		return;
408 
409 	kfree((struct sf_flow_acts __force *)flow->sf_acts);
410 	kmem_cache_free(flow_cache, flow);
411 }
412 
413 /* RCU callback used by ovs_flow_deferred_free. */
414 static void rcu_free_flow_callback(struct rcu_head *rcu)
415 {
416 	struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
417 
418 	ovs_flow_free(flow);
419 }
420 
421 /* Schedules 'flow' to be freed after the next RCU grace period.
422  * The caller must hold rcu_read_lock for this to be sensible. */
423 void ovs_flow_deferred_free(struct sw_flow *flow)
424 {
425 	call_rcu(&flow->rcu, rcu_free_flow_callback);
426 }
427 
428 /* RCU callback used by ovs_flow_deferred_free_acts. */
429 static void rcu_free_acts_callback(struct rcu_head *rcu)
430 {
431 	struct sw_flow_actions *sf_acts = container_of(rcu,
432 			struct sw_flow_actions, rcu);
433 	kfree(sf_acts);
434 }
435 
436 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
437  * The caller must hold rcu_read_lock for this to be sensible. */
438 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
439 {
440 	call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
441 }
442 
443 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
444 {
445 	struct qtag_prefix {
446 		__be16 eth_type; /* ETH_P_8021Q */
447 		__be16 tci;
448 	};
449 	struct qtag_prefix *qp;
450 
451 	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
452 		return 0;
453 
454 	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
455 					 sizeof(__be16))))
456 		return -ENOMEM;
457 
458 	qp = (struct qtag_prefix *) skb->data;
459 	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
460 	__skb_pull(skb, sizeof(struct qtag_prefix));
461 
462 	return 0;
463 }
464 
465 static __be16 parse_ethertype(struct sk_buff *skb)
466 {
467 	struct llc_snap_hdr {
468 		u8  dsap;  /* Always 0xAA */
469 		u8  ssap;  /* Always 0xAA */
470 		u8  ctrl;
471 		u8  oui[3];
472 		__be16 ethertype;
473 	};
474 	struct llc_snap_hdr *llc;
475 	__be16 proto;
476 
477 	proto = *(__be16 *) skb->data;
478 	__skb_pull(skb, sizeof(__be16));
479 
480 	if (ntohs(proto) >= 1536)
481 		return proto;
482 
483 	if (skb->len < sizeof(struct llc_snap_hdr))
484 		return htons(ETH_P_802_2);
485 
486 	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
487 		return htons(0);
488 
489 	llc = (struct llc_snap_hdr *) skb->data;
490 	if (llc->dsap != LLC_SAP_SNAP ||
491 	    llc->ssap != LLC_SAP_SNAP ||
492 	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
493 		return htons(ETH_P_802_2);
494 
495 	__skb_pull(skb, sizeof(struct llc_snap_hdr));
496 	return llc->ethertype;
497 }
498 
499 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
500 			int *key_lenp, int nh_len)
501 {
502 	struct icmp6hdr *icmp = icmp6_hdr(skb);
503 	int error = 0;
504 	int key_len;
505 
506 	/* The ICMPv6 type and code fields use the 16-bit transport port
507 	 * fields, so we need to store them in 16-bit network byte order.
508 	 */
509 	key->ipv6.tp.src = htons(icmp->icmp6_type);
510 	key->ipv6.tp.dst = htons(icmp->icmp6_code);
511 	key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
512 
513 	if (icmp->icmp6_code == 0 &&
514 	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
515 	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
516 		int icmp_len = skb->len - skb_transport_offset(skb);
517 		struct nd_msg *nd;
518 		int offset;
519 
520 		key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
521 
522 		/* In order to process neighbor discovery options, we need the
523 		 * entire packet.
524 		 */
525 		if (unlikely(icmp_len < sizeof(*nd)))
526 			goto out;
527 		if (unlikely(skb_linearize(skb))) {
528 			error = -ENOMEM;
529 			goto out;
530 		}
531 
532 		nd = (struct nd_msg *)skb_transport_header(skb);
533 		key->ipv6.nd.target = nd->target;
534 		key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
535 
536 		icmp_len -= sizeof(*nd);
537 		offset = 0;
538 		while (icmp_len >= 8) {
539 			struct nd_opt_hdr *nd_opt =
540 				 (struct nd_opt_hdr *)(nd->opt + offset);
541 			int opt_len = nd_opt->nd_opt_len * 8;
542 
543 			if (unlikely(!opt_len || opt_len > icmp_len))
544 				goto invalid;
545 
546 			/* Store the link layer address if the appropriate
547 			 * option is provided.  It is considered an error if
548 			 * the same link layer option is specified twice.
549 			 */
550 			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
551 			    && opt_len == 8) {
552 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
553 					goto invalid;
554 				memcpy(key->ipv6.nd.sll,
555 				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
556 			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
557 				   && opt_len == 8) {
558 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
559 					goto invalid;
560 				memcpy(key->ipv6.nd.tll,
561 				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
562 			}
563 
564 			icmp_len -= opt_len;
565 			offset += opt_len;
566 		}
567 	}
568 
569 	goto out;
570 
571 invalid:
572 	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
573 	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
574 	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
575 
576 out:
577 	*key_lenp = key_len;
578 	return error;
579 }
580 
581 /**
582  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
583  * @skb: sk_buff that contains the frame, with skb->data pointing to the
584  * Ethernet header
585  * @in_port: port number on which @skb was received.
586  * @key: output flow key
587  * @key_lenp: length of output flow key
588  *
589  * The caller must ensure that skb->len >= ETH_HLEN.
590  *
591  * Returns 0 if successful, otherwise a negative errno value.
592  *
593  * Initializes @skb header pointers as follows:
594  *
595  *    - skb->mac_header: the Ethernet header.
596  *
597  *    - skb->network_header: just past the Ethernet header, or just past the
598  *      VLAN header, to the first byte of the Ethernet payload.
599  *
600  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
601  *      on output, then just past the IP header, if one is present and
602  *      of a correct length, otherwise the same as skb->network_header.
603  *      For other key->dl_type values it is left untouched.
604  */
605 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
606 		 int *key_lenp)
607 {
608 	int error = 0;
609 	int key_len = SW_FLOW_KEY_OFFSET(eth);
610 	struct ethhdr *eth;
611 
612 	memset(key, 0, sizeof(*key));
613 
614 	key->phy.priority = skb->priority;
615 	key->phy.in_port = in_port;
616 
617 	skb_reset_mac_header(skb);
618 
619 	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
620 	 * header in the linear data area.
621 	 */
622 	eth = eth_hdr(skb);
623 	memcpy(key->eth.src, eth->h_source, ETH_ALEN);
624 	memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
625 
626 	__skb_pull(skb, 2 * ETH_ALEN);
627 
628 	if (vlan_tx_tag_present(skb))
629 		key->eth.tci = htons(skb->vlan_tci);
630 	else if (eth->h_proto == htons(ETH_P_8021Q))
631 		if (unlikely(parse_vlan(skb, key)))
632 			return -ENOMEM;
633 
634 	key->eth.type = parse_ethertype(skb);
635 	if (unlikely(key->eth.type == htons(0)))
636 		return -ENOMEM;
637 
638 	skb_reset_network_header(skb);
639 	__skb_push(skb, skb->data - skb_mac_header(skb));
640 
641 	/* Network layer. */
642 	if (key->eth.type == htons(ETH_P_IP)) {
643 		struct iphdr *nh;
644 		__be16 offset;
645 
646 		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
647 
648 		error = check_iphdr(skb);
649 		if (unlikely(error)) {
650 			if (error == -EINVAL) {
651 				skb->transport_header = skb->network_header;
652 				error = 0;
653 			}
654 			goto out;
655 		}
656 
657 		nh = ip_hdr(skb);
658 		key->ipv4.addr.src = nh->saddr;
659 		key->ipv4.addr.dst = nh->daddr;
660 
661 		key->ip.proto = nh->protocol;
662 		key->ip.tos = nh->tos;
663 		key->ip.ttl = nh->ttl;
664 
665 		offset = nh->frag_off & htons(IP_OFFSET);
666 		if (offset) {
667 			key->ip.frag = OVS_FRAG_TYPE_LATER;
668 			goto out;
669 		}
670 		if (nh->frag_off & htons(IP_MF) ||
671 			 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
672 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
673 
674 		/* Transport layer. */
675 		if (key->ip.proto == IPPROTO_TCP) {
676 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
677 			if (tcphdr_ok(skb)) {
678 				struct tcphdr *tcp = tcp_hdr(skb);
679 				key->ipv4.tp.src = tcp->source;
680 				key->ipv4.tp.dst = tcp->dest;
681 			}
682 		} else if (key->ip.proto == IPPROTO_UDP) {
683 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
684 			if (udphdr_ok(skb)) {
685 				struct udphdr *udp = udp_hdr(skb);
686 				key->ipv4.tp.src = udp->source;
687 				key->ipv4.tp.dst = udp->dest;
688 			}
689 		} else if (key->ip.proto == IPPROTO_ICMP) {
690 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
691 			if (icmphdr_ok(skb)) {
692 				struct icmphdr *icmp = icmp_hdr(skb);
693 				/* The ICMP type and code fields use the 16-bit
694 				 * transport port fields, so we need to store
695 				 * them in 16-bit network byte order. */
696 				key->ipv4.tp.src = htons(icmp->type);
697 				key->ipv4.tp.dst = htons(icmp->code);
698 			}
699 		}
700 
701 	} else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
702 		struct arp_eth_header *arp;
703 
704 		arp = (struct arp_eth_header *)skb_network_header(skb);
705 
706 		if (arp->ar_hrd == htons(ARPHRD_ETHER)
707 				&& arp->ar_pro == htons(ETH_P_IP)
708 				&& arp->ar_hln == ETH_ALEN
709 				&& arp->ar_pln == 4) {
710 
711 			/* We only match on the lower 8 bits of the opcode. */
712 			if (ntohs(arp->ar_op) <= 0xff)
713 				key->ip.proto = ntohs(arp->ar_op);
714 
715 			if (key->ip.proto == ARPOP_REQUEST
716 					|| key->ip.proto == ARPOP_REPLY) {
717 				memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
718 				memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
719 				memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
720 				memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
721 				key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
722 			}
723 		}
724 	} else if (key->eth.type == htons(ETH_P_IPV6)) {
725 		int nh_len;             /* IPv6 Header + Extensions */
726 
727 		nh_len = parse_ipv6hdr(skb, key, &key_len);
728 		if (unlikely(nh_len < 0)) {
729 			if (nh_len == -EINVAL)
730 				skb->transport_header = skb->network_header;
731 			else
732 				error = nh_len;
733 			goto out;
734 		}
735 
736 		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
737 			goto out;
738 		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
739 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
740 
741 		/* Transport layer. */
742 		if (key->ip.proto == NEXTHDR_TCP) {
743 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
744 			if (tcphdr_ok(skb)) {
745 				struct tcphdr *tcp = tcp_hdr(skb);
746 				key->ipv6.tp.src = tcp->source;
747 				key->ipv6.tp.dst = tcp->dest;
748 			}
749 		} else if (key->ip.proto == NEXTHDR_UDP) {
750 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
751 			if (udphdr_ok(skb)) {
752 				struct udphdr *udp = udp_hdr(skb);
753 				key->ipv6.tp.src = udp->source;
754 				key->ipv6.tp.dst = udp->dest;
755 			}
756 		} else if (key->ip.proto == NEXTHDR_ICMP) {
757 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
758 			if (icmp6hdr_ok(skb)) {
759 				error = parse_icmpv6(skb, key, &key_len, nh_len);
760 				if (error < 0)
761 					goto out;
762 			}
763 		}
764 	}
765 
766 out:
767 	*key_lenp = key_len;
768 	return error;
769 }
770 
771 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
772 {
773 	return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
774 }
775 
776 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
777 				struct sw_flow_key *key, int key_len)
778 {
779 	struct sw_flow *flow;
780 	struct hlist_node *n;
781 	struct hlist_head *head;
782 	u32 hash;
783 
784 	hash = ovs_flow_hash(key, key_len);
785 
786 	head = find_bucket(table, hash);
787 	hlist_for_each_entry_rcu(flow, n, head, hash_node[table->node_ver]) {
788 
789 		if (flow->hash == hash &&
790 		    !memcmp(&flow->key, key, key_len)) {
791 			return flow;
792 		}
793 	}
794 	return NULL;
795 }
796 
797 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
798 {
799 	struct hlist_head *head;
800 
801 	head = find_bucket(table, flow->hash);
802 	hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
803 	table->count++;
804 }
805 
806 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
807 {
808 	hlist_del_rcu(&flow->hash_node[table->node_ver]);
809 	table->count--;
810 	BUG_ON(table->count < 0);
811 }
812 
813 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
814 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
815 	[OVS_KEY_ATTR_ENCAP] = -1,
816 	[OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
817 	[OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
818 	[OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
819 	[OVS_KEY_ATTR_VLAN] = sizeof(__be16),
820 	[OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
821 	[OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
822 	[OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
823 	[OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
824 	[OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
825 	[OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
826 	[OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
827 	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
828 	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
829 };
830 
831 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
832 				  const struct nlattr *a[], u32 *attrs)
833 {
834 	const struct ovs_key_icmp *icmp_key;
835 	const struct ovs_key_tcp *tcp_key;
836 	const struct ovs_key_udp *udp_key;
837 
838 	switch (swkey->ip.proto) {
839 	case IPPROTO_TCP:
840 		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
841 			return -EINVAL;
842 		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
843 
844 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
845 		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
846 		swkey->ipv4.tp.src = tcp_key->tcp_src;
847 		swkey->ipv4.tp.dst = tcp_key->tcp_dst;
848 		break;
849 
850 	case IPPROTO_UDP:
851 		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
852 			return -EINVAL;
853 		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
854 
855 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
856 		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
857 		swkey->ipv4.tp.src = udp_key->udp_src;
858 		swkey->ipv4.tp.dst = udp_key->udp_dst;
859 		break;
860 
861 	case IPPROTO_ICMP:
862 		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
863 			return -EINVAL;
864 		*attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
865 
866 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
867 		icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
868 		swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
869 		swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
870 		break;
871 	}
872 
873 	return 0;
874 }
875 
876 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
877 				  const struct nlattr *a[], u32 *attrs)
878 {
879 	const struct ovs_key_icmpv6 *icmpv6_key;
880 	const struct ovs_key_tcp *tcp_key;
881 	const struct ovs_key_udp *udp_key;
882 
883 	switch (swkey->ip.proto) {
884 	case IPPROTO_TCP:
885 		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
886 			return -EINVAL;
887 		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
888 
889 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
890 		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
891 		swkey->ipv6.tp.src = tcp_key->tcp_src;
892 		swkey->ipv6.tp.dst = tcp_key->tcp_dst;
893 		break;
894 
895 	case IPPROTO_UDP:
896 		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
897 			return -EINVAL;
898 		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
899 
900 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
901 		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
902 		swkey->ipv6.tp.src = udp_key->udp_src;
903 		swkey->ipv6.tp.dst = udp_key->udp_dst;
904 		break;
905 
906 	case IPPROTO_ICMPV6:
907 		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
908 			return -EINVAL;
909 		*attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
910 
911 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
912 		icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
913 		swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
914 		swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
915 
916 		if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
917 		    swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
918 			const struct ovs_key_nd *nd_key;
919 
920 			if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
921 				return -EINVAL;
922 			*attrs &= ~(1 << OVS_KEY_ATTR_ND);
923 
924 			*key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
925 			nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
926 			memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
927 			       sizeof(swkey->ipv6.nd.target));
928 			memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
929 			memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
930 		}
931 		break;
932 	}
933 
934 	return 0;
935 }
936 
937 static int parse_flow_nlattrs(const struct nlattr *attr,
938 			      const struct nlattr *a[], u32 *attrsp)
939 {
940 	const struct nlattr *nla;
941 	u32 attrs;
942 	int rem;
943 
944 	attrs = 0;
945 	nla_for_each_nested(nla, attr, rem) {
946 		u16 type = nla_type(nla);
947 		int expected_len;
948 
949 		if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
950 			return -EINVAL;
951 
952 		expected_len = ovs_key_lens[type];
953 		if (nla_len(nla) != expected_len && expected_len != -1)
954 			return -EINVAL;
955 
956 		attrs |= 1 << type;
957 		a[type] = nla;
958 	}
959 	if (rem)
960 		return -EINVAL;
961 
962 	*attrsp = attrs;
963 	return 0;
964 }
965 
966 /**
967  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
968  * @swkey: receives the extracted flow key.
969  * @key_lenp: number of bytes used in @swkey.
970  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
971  * sequence.
972  */
973 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
974 		      const struct nlattr *attr)
975 {
976 	const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
977 	const struct ovs_key_ethernet *eth_key;
978 	int key_len;
979 	u32 attrs;
980 	int err;
981 
982 	memset(swkey, 0, sizeof(struct sw_flow_key));
983 	key_len = SW_FLOW_KEY_OFFSET(eth);
984 
985 	err = parse_flow_nlattrs(attr, a, &attrs);
986 	if (err)
987 		return err;
988 
989 	/* Metadata attributes. */
990 	if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
991 		swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
992 		attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
993 	}
994 	if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
995 		u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
996 		if (in_port >= DP_MAX_PORTS)
997 			return -EINVAL;
998 		swkey->phy.in_port = in_port;
999 		attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1000 	} else {
1001 		swkey->phy.in_port = USHRT_MAX;
1002 	}
1003 
1004 	/* Data attributes. */
1005 	if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1006 		return -EINVAL;
1007 	attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1008 
1009 	eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1010 	memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1011 	memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1012 
1013 	if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1014 	    nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1015 		const struct nlattr *encap;
1016 		__be16 tci;
1017 
1018 		if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1019 			      (1 << OVS_KEY_ATTR_ETHERTYPE) |
1020 			      (1 << OVS_KEY_ATTR_ENCAP)))
1021 			return -EINVAL;
1022 
1023 		encap = a[OVS_KEY_ATTR_ENCAP];
1024 		tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1025 		if (tci & htons(VLAN_TAG_PRESENT)) {
1026 			swkey->eth.tci = tci;
1027 
1028 			err = parse_flow_nlattrs(encap, a, &attrs);
1029 			if (err)
1030 				return err;
1031 		} else if (!tci) {
1032 			/* Corner case for truncated 802.1Q header. */
1033 			if (nla_len(encap))
1034 				return -EINVAL;
1035 
1036 			swkey->eth.type = htons(ETH_P_8021Q);
1037 			*key_lenp = key_len;
1038 			return 0;
1039 		} else {
1040 			return -EINVAL;
1041 		}
1042 	}
1043 
1044 	if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1045 		swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1046 		if (ntohs(swkey->eth.type) < 1536)
1047 			return -EINVAL;
1048 		attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1049 	} else {
1050 		swkey->eth.type = htons(ETH_P_802_2);
1051 	}
1052 
1053 	if (swkey->eth.type == htons(ETH_P_IP)) {
1054 		const struct ovs_key_ipv4 *ipv4_key;
1055 
1056 		if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1057 			return -EINVAL;
1058 		attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1059 
1060 		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1061 		ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1062 		if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1063 			return -EINVAL;
1064 		swkey->ip.proto = ipv4_key->ipv4_proto;
1065 		swkey->ip.tos = ipv4_key->ipv4_tos;
1066 		swkey->ip.ttl = ipv4_key->ipv4_ttl;
1067 		swkey->ip.frag = ipv4_key->ipv4_frag;
1068 		swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1069 		swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1070 
1071 		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1072 			err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1073 			if (err)
1074 				return err;
1075 		}
1076 	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1077 		const struct ovs_key_ipv6 *ipv6_key;
1078 
1079 		if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1080 			return -EINVAL;
1081 		attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1082 
1083 		key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1084 		ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1085 		if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1086 			return -EINVAL;
1087 		swkey->ipv6.label = ipv6_key->ipv6_label;
1088 		swkey->ip.proto = ipv6_key->ipv6_proto;
1089 		swkey->ip.tos = ipv6_key->ipv6_tclass;
1090 		swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1091 		swkey->ip.frag = ipv6_key->ipv6_frag;
1092 		memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1093 		       sizeof(swkey->ipv6.addr.src));
1094 		memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1095 		       sizeof(swkey->ipv6.addr.dst));
1096 
1097 		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1098 			err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1099 			if (err)
1100 				return err;
1101 		}
1102 	} else if (swkey->eth.type == htons(ETH_P_ARP)) {
1103 		const struct ovs_key_arp *arp_key;
1104 
1105 		if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1106 			return -EINVAL;
1107 		attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1108 
1109 		key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1110 		arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1111 		swkey->ipv4.addr.src = arp_key->arp_sip;
1112 		swkey->ipv4.addr.dst = arp_key->arp_tip;
1113 		if (arp_key->arp_op & htons(0xff00))
1114 			return -EINVAL;
1115 		swkey->ip.proto = ntohs(arp_key->arp_op);
1116 		memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1117 		memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1118 	}
1119 
1120 	if (attrs)
1121 		return -EINVAL;
1122 	*key_lenp = key_len;
1123 
1124 	return 0;
1125 }
1126 
1127 /**
1128  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1129  * @in_port: receives the extracted input port.
1130  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1131  * sequence.
1132  *
1133  * This parses a series of Netlink attributes that form a flow key, which must
1134  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1135  * get the metadata, that is, the parts of the flow key that cannot be
1136  * extracted from the packet itself.
1137  */
1138 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port,
1139 			       const struct nlattr *attr)
1140 {
1141 	const struct nlattr *nla;
1142 	int rem;
1143 
1144 	*in_port = USHRT_MAX;
1145 	*priority = 0;
1146 
1147 	nla_for_each_nested(nla, attr, rem) {
1148 		int type = nla_type(nla);
1149 
1150 		if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1151 			if (nla_len(nla) != ovs_key_lens[type])
1152 				return -EINVAL;
1153 
1154 			switch (type) {
1155 			case OVS_KEY_ATTR_PRIORITY:
1156 				*priority = nla_get_u32(nla);
1157 				break;
1158 
1159 			case OVS_KEY_ATTR_IN_PORT:
1160 				if (nla_get_u32(nla) >= DP_MAX_PORTS)
1161 					return -EINVAL;
1162 				*in_port = nla_get_u32(nla);
1163 				break;
1164 			}
1165 		}
1166 	}
1167 	if (rem)
1168 		return -EINVAL;
1169 	return 0;
1170 }
1171 
1172 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1173 {
1174 	struct ovs_key_ethernet *eth_key;
1175 	struct nlattr *nla, *encap;
1176 
1177 	if (swkey->phy.priority)
1178 		NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
1179 
1180 	if (swkey->phy.in_port != USHRT_MAX)
1181 		NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
1182 
1183 	nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1184 	if (!nla)
1185 		goto nla_put_failure;
1186 	eth_key = nla_data(nla);
1187 	memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1188 	memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1189 
1190 	if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1191 		NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q));
1192 		NLA_PUT_BE16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci);
1193 		encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1194 		if (!swkey->eth.tci)
1195 			goto unencap;
1196 	} else {
1197 		encap = NULL;
1198 	}
1199 
1200 	if (swkey->eth.type == htons(ETH_P_802_2))
1201 		goto unencap;
1202 
1203 	NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
1204 
1205 	if (swkey->eth.type == htons(ETH_P_IP)) {
1206 		struct ovs_key_ipv4 *ipv4_key;
1207 
1208 		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1209 		if (!nla)
1210 			goto nla_put_failure;
1211 		ipv4_key = nla_data(nla);
1212 		ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1213 		ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1214 		ipv4_key->ipv4_proto = swkey->ip.proto;
1215 		ipv4_key->ipv4_tos = swkey->ip.tos;
1216 		ipv4_key->ipv4_ttl = swkey->ip.ttl;
1217 		ipv4_key->ipv4_frag = swkey->ip.frag;
1218 	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1219 		struct ovs_key_ipv6 *ipv6_key;
1220 
1221 		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1222 		if (!nla)
1223 			goto nla_put_failure;
1224 		ipv6_key = nla_data(nla);
1225 		memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1226 				sizeof(ipv6_key->ipv6_src));
1227 		memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1228 				sizeof(ipv6_key->ipv6_dst));
1229 		ipv6_key->ipv6_label = swkey->ipv6.label;
1230 		ipv6_key->ipv6_proto = swkey->ip.proto;
1231 		ipv6_key->ipv6_tclass = swkey->ip.tos;
1232 		ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1233 		ipv6_key->ipv6_frag = swkey->ip.frag;
1234 	} else if (swkey->eth.type == htons(ETH_P_ARP)) {
1235 		struct ovs_key_arp *arp_key;
1236 
1237 		nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1238 		if (!nla)
1239 			goto nla_put_failure;
1240 		arp_key = nla_data(nla);
1241 		memset(arp_key, 0, sizeof(struct ovs_key_arp));
1242 		arp_key->arp_sip = swkey->ipv4.addr.src;
1243 		arp_key->arp_tip = swkey->ipv4.addr.dst;
1244 		arp_key->arp_op = htons(swkey->ip.proto);
1245 		memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1246 		memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1247 	}
1248 
1249 	if ((swkey->eth.type == htons(ETH_P_IP) ||
1250 	     swkey->eth.type == htons(ETH_P_IPV6)) &&
1251 	     swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1252 
1253 		if (swkey->ip.proto == IPPROTO_TCP) {
1254 			struct ovs_key_tcp *tcp_key;
1255 
1256 			nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1257 			if (!nla)
1258 				goto nla_put_failure;
1259 			tcp_key = nla_data(nla);
1260 			if (swkey->eth.type == htons(ETH_P_IP)) {
1261 				tcp_key->tcp_src = swkey->ipv4.tp.src;
1262 				tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1263 			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1264 				tcp_key->tcp_src = swkey->ipv6.tp.src;
1265 				tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1266 			}
1267 		} else if (swkey->ip.proto == IPPROTO_UDP) {
1268 			struct ovs_key_udp *udp_key;
1269 
1270 			nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1271 			if (!nla)
1272 				goto nla_put_failure;
1273 			udp_key = nla_data(nla);
1274 			if (swkey->eth.type == htons(ETH_P_IP)) {
1275 				udp_key->udp_src = swkey->ipv4.tp.src;
1276 				udp_key->udp_dst = swkey->ipv4.tp.dst;
1277 			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1278 				udp_key->udp_src = swkey->ipv6.tp.src;
1279 				udp_key->udp_dst = swkey->ipv6.tp.dst;
1280 			}
1281 		} else if (swkey->eth.type == htons(ETH_P_IP) &&
1282 			   swkey->ip.proto == IPPROTO_ICMP) {
1283 			struct ovs_key_icmp *icmp_key;
1284 
1285 			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1286 			if (!nla)
1287 				goto nla_put_failure;
1288 			icmp_key = nla_data(nla);
1289 			icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1290 			icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1291 		} else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1292 			   swkey->ip.proto == IPPROTO_ICMPV6) {
1293 			struct ovs_key_icmpv6 *icmpv6_key;
1294 
1295 			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1296 						sizeof(*icmpv6_key));
1297 			if (!nla)
1298 				goto nla_put_failure;
1299 			icmpv6_key = nla_data(nla);
1300 			icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1301 			icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1302 
1303 			if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1304 			    icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1305 				struct ovs_key_nd *nd_key;
1306 
1307 				nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1308 				if (!nla)
1309 					goto nla_put_failure;
1310 				nd_key = nla_data(nla);
1311 				memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1312 							sizeof(nd_key->nd_target));
1313 				memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1314 				memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1315 			}
1316 		}
1317 	}
1318 
1319 unencap:
1320 	if (encap)
1321 		nla_nest_end(skb, encap);
1322 
1323 	return 0;
1324 
1325 nla_put_failure:
1326 	return -EMSGSIZE;
1327 }
1328 
1329 /* Initializes the flow module.
1330  * Returns zero if successful or a negative error code. */
1331 int ovs_flow_init(void)
1332 {
1333 	flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1334 					0, NULL);
1335 	if (flow_cache == NULL)
1336 		return -ENOMEM;
1337 
1338 	return 0;
1339 }
1340 
1341 /* Uninitializes the flow module. */
1342 void ovs_flow_exit(void)
1343 {
1344 	kmem_cache_destroy(flow_cache);
1345 }
1346