xref: /openbmc/linux/net/openvswitch/flow.c (revision 93d8fd15)
1 /*
2  * Copyright (c) 2007-2011 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 "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.eth.type == htons(ETH_P_IPV6)) &&
187 	    flow->key.ip.proto == IPPROTO_TCP &&
188 	    likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
189 		u8 *tcp = (u8 *)tcp_hdr(skb);
190 		tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
191 	}
192 
193 	spin_lock(&flow->lock);
194 	flow->used = jiffies;
195 	flow->packet_count++;
196 	flow->byte_count += skb->len;
197 	flow->tcp_flags |= tcp_flags;
198 	spin_unlock(&flow->lock);
199 }
200 
201 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
202 {
203 	int actions_len = nla_len(actions);
204 	struct sw_flow_actions *sfa;
205 
206 	if (actions_len > MAX_ACTIONS_BUFSIZE)
207 		return ERR_PTR(-EINVAL);
208 
209 	sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
210 	if (!sfa)
211 		return ERR_PTR(-ENOMEM);
212 
213 	sfa->actions_len = actions_len;
214 	nla_memcpy(sfa->actions, actions, actions_len);
215 	return sfa;
216 }
217 
218 struct sw_flow *ovs_flow_alloc(void)
219 {
220 	struct sw_flow *flow;
221 
222 	flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
223 	if (!flow)
224 		return ERR_PTR(-ENOMEM);
225 
226 	spin_lock_init(&flow->lock);
227 	flow->sf_acts = NULL;
228 
229 	return flow;
230 }
231 
232 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
233 {
234 	hash = jhash_1word(hash, table->hash_seed);
235 	return flex_array_get(table->buckets,
236 				(hash & (table->n_buckets - 1)));
237 }
238 
239 static struct flex_array *alloc_buckets(unsigned int n_buckets)
240 {
241 	struct flex_array *buckets;
242 	int i, err;
243 
244 	buckets = flex_array_alloc(sizeof(struct hlist_head *),
245 				   n_buckets, GFP_KERNEL);
246 	if (!buckets)
247 		return NULL;
248 
249 	err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
250 	if (err) {
251 		flex_array_free(buckets);
252 		return NULL;
253 	}
254 
255 	for (i = 0; i < n_buckets; i++)
256 		INIT_HLIST_HEAD((struct hlist_head *)
257 					flex_array_get(buckets, i));
258 
259 	return buckets;
260 }
261 
262 static void free_buckets(struct flex_array *buckets)
263 {
264 	flex_array_free(buckets);
265 }
266 
267 struct flow_table *ovs_flow_tbl_alloc(int new_size)
268 {
269 	struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
270 
271 	if (!table)
272 		return NULL;
273 
274 	table->buckets = alloc_buckets(new_size);
275 
276 	if (!table->buckets) {
277 		kfree(table);
278 		return NULL;
279 	}
280 	table->n_buckets = new_size;
281 	table->count = 0;
282 	table->node_ver = 0;
283 	table->keep_flows = false;
284 	get_random_bytes(&table->hash_seed, sizeof(u32));
285 
286 	return table;
287 }
288 
289 void ovs_flow_tbl_destroy(struct flow_table *table)
290 {
291 	int i;
292 
293 	if (!table)
294 		return;
295 
296 	if (table->keep_flows)
297 		goto skip_flows;
298 
299 	for (i = 0; i < table->n_buckets; i++) {
300 		struct sw_flow *flow;
301 		struct hlist_head *head = flex_array_get(table->buckets, i);
302 		struct hlist_node *n;
303 		int ver = table->node_ver;
304 
305 		hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
306 			hlist_del_rcu(&flow->hash_node[ver]);
307 			ovs_flow_free(flow);
308 		}
309 	}
310 
311 skip_flows:
312 	free_buckets(table->buckets);
313 	kfree(table);
314 }
315 
316 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
317 {
318 	struct flow_table *table = container_of(rcu, struct flow_table, rcu);
319 
320 	ovs_flow_tbl_destroy(table);
321 }
322 
323 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
324 {
325 	if (!table)
326 		return;
327 
328 	call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
329 }
330 
331 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
332 {
333 	struct sw_flow *flow;
334 	struct hlist_head *head;
335 	int ver;
336 	int i;
337 
338 	ver = table->node_ver;
339 	while (*bucket < table->n_buckets) {
340 		i = 0;
341 		head = flex_array_get(table->buckets, *bucket);
342 		hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
343 			if (i < *last) {
344 				i++;
345 				continue;
346 			}
347 			*last = i + 1;
348 			return flow;
349 		}
350 		(*bucket)++;
351 		*last = 0;
352 	}
353 
354 	return NULL;
355 }
356 
357 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
358 {
359 	int old_ver;
360 	int i;
361 
362 	old_ver = old->node_ver;
363 	new->node_ver = !old_ver;
364 
365 	/* Insert in new table. */
366 	for (i = 0; i < old->n_buckets; i++) {
367 		struct sw_flow *flow;
368 		struct hlist_head *head;
369 
370 		head = flex_array_get(old->buckets, i);
371 
372 		hlist_for_each_entry(flow, head, hash_node[old_ver])
373 			ovs_flow_tbl_insert(new, flow);
374 	}
375 	old->keep_flows = true;
376 }
377 
378 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
379 {
380 	struct flow_table *new_table;
381 
382 	new_table = ovs_flow_tbl_alloc(n_buckets);
383 	if (!new_table)
384 		return ERR_PTR(-ENOMEM);
385 
386 	flow_table_copy_flows(table, new_table);
387 
388 	return new_table;
389 }
390 
391 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
392 {
393 	return __flow_tbl_rehash(table, table->n_buckets);
394 }
395 
396 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
397 {
398 	return __flow_tbl_rehash(table, table->n_buckets * 2);
399 }
400 
401 void ovs_flow_free(struct sw_flow *flow)
402 {
403 	if (unlikely(!flow))
404 		return;
405 
406 	kfree((struct sf_flow_acts __force *)flow->sf_acts);
407 	kmem_cache_free(flow_cache, flow);
408 }
409 
410 /* RCU callback used by ovs_flow_deferred_free. */
411 static void rcu_free_flow_callback(struct rcu_head *rcu)
412 {
413 	struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
414 
415 	ovs_flow_free(flow);
416 }
417 
418 /* Schedules 'flow' to be freed after the next RCU grace period.
419  * The caller must hold rcu_read_lock for this to be sensible. */
420 void ovs_flow_deferred_free(struct sw_flow *flow)
421 {
422 	call_rcu(&flow->rcu, rcu_free_flow_callback);
423 }
424 
425 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
426  * The caller must hold rcu_read_lock for this to be sensible. */
427 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
428 {
429 	kfree_rcu(sf_acts, rcu);
430 }
431 
432 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
433 {
434 	struct qtag_prefix {
435 		__be16 eth_type; /* ETH_P_8021Q */
436 		__be16 tci;
437 	};
438 	struct qtag_prefix *qp;
439 
440 	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
441 		return 0;
442 
443 	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
444 					 sizeof(__be16))))
445 		return -ENOMEM;
446 
447 	qp = (struct qtag_prefix *) skb->data;
448 	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
449 	__skb_pull(skb, sizeof(struct qtag_prefix));
450 
451 	return 0;
452 }
453 
454 static __be16 parse_ethertype(struct sk_buff *skb)
455 {
456 	struct llc_snap_hdr {
457 		u8  dsap;  /* Always 0xAA */
458 		u8  ssap;  /* Always 0xAA */
459 		u8  ctrl;
460 		u8  oui[3];
461 		__be16 ethertype;
462 	};
463 	struct llc_snap_hdr *llc;
464 	__be16 proto;
465 
466 	proto = *(__be16 *) skb->data;
467 	__skb_pull(skb, sizeof(__be16));
468 
469 	if (ntohs(proto) >= ETH_P_802_3_MIN)
470 		return proto;
471 
472 	if (skb->len < sizeof(struct llc_snap_hdr))
473 		return htons(ETH_P_802_2);
474 
475 	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
476 		return htons(0);
477 
478 	llc = (struct llc_snap_hdr *) skb->data;
479 	if (llc->dsap != LLC_SAP_SNAP ||
480 	    llc->ssap != LLC_SAP_SNAP ||
481 	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
482 		return htons(ETH_P_802_2);
483 
484 	__skb_pull(skb, sizeof(struct llc_snap_hdr));
485 
486 	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
487 		return llc->ethertype;
488 
489 	return htons(ETH_P_802_2);
490 }
491 
492 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
493 			int *key_lenp, int nh_len)
494 {
495 	struct icmp6hdr *icmp = icmp6_hdr(skb);
496 	int error = 0;
497 	int key_len;
498 
499 	/* The ICMPv6 type and code fields use the 16-bit transport port
500 	 * fields, so we need to store them in 16-bit network byte order.
501 	 */
502 	key->ipv6.tp.src = htons(icmp->icmp6_type);
503 	key->ipv6.tp.dst = htons(icmp->icmp6_code);
504 	key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
505 
506 	if (icmp->icmp6_code == 0 &&
507 	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
508 	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
509 		int icmp_len = skb->len - skb_transport_offset(skb);
510 		struct nd_msg *nd;
511 		int offset;
512 
513 		key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
514 
515 		/* In order to process neighbor discovery options, we need the
516 		 * entire packet.
517 		 */
518 		if (unlikely(icmp_len < sizeof(*nd)))
519 			goto out;
520 		if (unlikely(skb_linearize(skb))) {
521 			error = -ENOMEM;
522 			goto out;
523 		}
524 
525 		nd = (struct nd_msg *)skb_transport_header(skb);
526 		key->ipv6.nd.target = nd->target;
527 		key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
528 
529 		icmp_len -= sizeof(*nd);
530 		offset = 0;
531 		while (icmp_len >= 8) {
532 			struct nd_opt_hdr *nd_opt =
533 				 (struct nd_opt_hdr *)(nd->opt + offset);
534 			int opt_len = nd_opt->nd_opt_len * 8;
535 
536 			if (unlikely(!opt_len || opt_len > icmp_len))
537 				goto invalid;
538 
539 			/* Store the link layer address if the appropriate
540 			 * option is provided.  It is considered an error if
541 			 * the same link layer option is specified twice.
542 			 */
543 			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
544 			    && opt_len == 8) {
545 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
546 					goto invalid;
547 				memcpy(key->ipv6.nd.sll,
548 				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
549 			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
550 				   && opt_len == 8) {
551 				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
552 					goto invalid;
553 				memcpy(key->ipv6.nd.tll,
554 				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
555 			}
556 
557 			icmp_len -= opt_len;
558 			offset += opt_len;
559 		}
560 	}
561 
562 	goto out;
563 
564 invalid:
565 	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
566 	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
567 	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
568 
569 out:
570 	*key_lenp = key_len;
571 	return error;
572 }
573 
574 /**
575  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
576  * @skb: sk_buff that contains the frame, with skb->data pointing to the
577  * Ethernet header
578  * @in_port: port number on which @skb was received.
579  * @key: output flow key
580  * @key_lenp: length of output flow key
581  *
582  * The caller must ensure that skb->len >= ETH_HLEN.
583  *
584  * Returns 0 if successful, otherwise a negative errno value.
585  *
586  * Initializes @skb header pointers as follows:
587  *
588  *    - skb->mac_header: the Ethernet header.
589  *
590  *    - skb->network_header: just past the Ethernet header, or just past the
591  *      VLAN header, to the first byte of the Ethernet payload.
592  *
593  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
594  *      on output, then just past the IP header, if one is present and
595  *      of a correct length, otherwise the same as skb->network_header.
596  *      For other key->eth.type values it is left untouched.
597  */
598 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
599 		 int *key_lenp)
600 {
601 	int error = 0;
602 	int key_len = SW_FLOW_KEY_OFFSET(eth);
603 	struct ethhdr *eth;
604 
605 	memset(key, 0, sizeof(*key));
606 
607 	key->phy.priority = skb->priority;
608 	key->phy.in_port = in_port;
609 	key->phy.skb_mark = skb->mark;
610 
611 	skb_reset_mac_header(skb);
612 
613 	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
614 	 * header in the linear data area.
615 	 */
616 	eth = eth_hdr(skb);
617 	memcpy(key->eth.src, eth->h_source, ETH_ALEN);
618 	memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
619 
620 	__skb_pull(skb, 2 * ETH_ALEN);
621 	/* We are going to push all headers that we pull, so no need to
622 	 * update skb->csum here.
623 	 */
624 
625 	if (vlan_tx_tag_present(skb))
626 		key->eth.tci = htons(skb->vlan_tci);
627 	else if (eth->h_proto == htons(ETH_P_8021Q))
628 		if (unlikely(parse_vlan(skb, key)))
629 			return -ENOMEM;
630 
631 	key->eth.type = parse_ethertype(skb);
632 	if (unlikely(key->eth.type == htons(0)))
633 		return -ENOMEM;
634 
635 	skb_reset_network_header(skb);
636 	__skb_push(skb, skb->data - skb_mac_header(skb));
637 
638 	/* Network layer. */
639 	if (key->eth.type == htons(ETH_P_IP)) {
640 		struct iphdr *nh;
641 		__be16 offset;
642 
643 		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
644 
645 		error = check_iphdr(skb);
646 		if (unlikely(error)) {
647 			if (error == -EINVAL) {
648 				skb->transport_header = skb->network_header;
649 				error = 0;
650 			}
651 			goto out;
652 		}
653 
654 		nh = ip_hdr(skb);
655 		key->ipv4.addr.src = nh->saddr;
656 		key->ipv4.addr.dst = nh->daddr;
657 
658 		key->ip.proto = nh->protocol;
659 		key->ip.tos = nh->tos;
660 		key->ip.ttl = nh->ttl;
661 
662 		offset = nh->frag_off & htons(IP_OFFSET);
663 		if (offset) {
664 			key->ip.frag = OVS_FRAG_TYPE_LATER;
665 			goto out;
666 		}
667 		if (nh->frag_off & htons(IP_MF) ||
668 			 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
669 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
670 
671 		/* Transport layer. */
672 		if (key->ip.proto == IPPROTO_TCP) {
673 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
674 			if (tcphdr_ok(skb)) {
675 				struct tcphdr *tcp = tcp_hdr(skb);
676 				key->ipv4.tp.src = tcp->source;
677 				key->ipv4.tp.dst = tcp->dest;
678 			}
679 		} else if (key->ip.proto == IPPROTO_UDP) {
680 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
681 			if (udphdr_ok(skb)) {
682 				struct udphdr *udp = udp_hdr(skb);
683 				key->ipv4.tp.src = udp->source;
684 				key->ipv4.tp.dst = udp->dest;
685 			}
686 		} else if (key->ip.proto == IPPROTO_ICMP) {
687 			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
688 			if (icmphdr_ok(skb)) {
689 				struct icmphdr *icmp = icmp_hdr(skb);
690 				/* The ICMP type and code fields use the 16-bit
691 				 * transport port fields, so we need to store
692 				 * them in 16-bit network byte order. */
693 				key->ipv4.tp.src = htons(icmp->type);
694 				key->ipv4.tp.dst = htons(icmp->code);
695 			}
696 		}
697 
698 	} else if ((key->eth.type == htons(ETH_P_ARP) ||
699 		   key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
700 		struct arp_eth_header *arp;
701 
702 		arp = (struct arp_eth_header *)skb_network_header(skb);
703 
704 		if (arp->ar_hrd == htons(ARPHRD_ETHER)
705 				&& arp->ar_pro == htons(ETH_P_IP)
706 				&& arp->ar_hln == ETH_ALEN
707 				&& arp->ar_pln == 4) {
708 
709 			/* We only match on the lower 8 bits of the opcode. */
710 			if (ntohs(arp->ar_op) <= 0xff)
711 				key->ip.proto = ntohs(arp->ar_op);
712 			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
713 			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
714 			memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
715 			memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
716 			key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
717 		}
718 	} else if (key->eth.type == htons(ETH_P_IPV6)) {
719 		int nh_len;             /* IPv6 Header + Extensions */
720 
721 		nh_len = parse_ipv6hdr(skb, key, &key_len);
722 		if (unlikely(nh_len < 0)) {
723 			if (nh_len == -EINVAL)
724 				skb->transport_header = skb->network_header;
725 			else
726 				error = nh_len;
727 			goto out;
728 		}
729 
730 		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
731 			goto out;
732 		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
733 			key->ip.frag = OVS_FRAG_TYPE_FIRST;
734 
735 		/* Transport layer. */
736 		if (key->ip.proto == NEXTHDR_TCP) {
737 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
738 			if (tcphdr_ok(skb)) {
739 				struct tcphdr *tcp = tcp_hdr(skb);
740 				key->ipv6.tp.src = tcp->source;
741 				key->ipv6.tp.dst = tcp->dest;
742 			}
743 		} else if (key->ip.proto == NEXTHDR_UDP) {
744 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
745 			if (udphdr_ok(skb)) {
746 				struct udphdr *udp = udp_hdr(skb);
747 				key->ipv6.tp.src = udp->source;
748 				key->ipv6.tp.dst = udp->dest;
749 			}
750 		} else if (key->ip.proto == NEXTHDR_ICMP) {
751 			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
752 			if (icmp6hdr_ok(skb)) {
753 				error = parse_icmpv6(skb, key, &key_len, nh_len);
754 				if (error < 0)
755 					goto out;
756 			}
757 		}
758 	}
759 
760 out:
761 	*key_lenp = key_len;
762 	return error;
763 }
764 
765 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
766 {
767 	return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
768 }
769 
770 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
771 				struct sw_flow_key *key, int key_len)
772 {
773 	struct sw_flow *flow;
774 	struct hlist_head *head;
775 	u32 hash;
776 
777 	hash = ovs_flow_hash(key, key_len);
778 
779 	head = find_bucket(table, hash);
780 	hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
781 
782 		if (flow->hash == hash &&
783 		    !memcmp(&flow->key, key, key_len)) {
784 			return flow;
785 		}
786 	}
787 	return NULL;
788 }
789 
790 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
791 {
792 	struct hlist_head *head;
793 
794 	head = find_bucket(table, flow->hash);
795 	hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
796 	table->count++;
797 }
798 
799 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
800 {
801 	BUG_ON(table->count == 0);
802 	hlist_del_rcu(&flow->hash_node[table->node_ver]);
803 	table->count--;
804 }
805 
806 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
807 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
808 	[OVS_KEY_ATTR_ENCAP] = -1,
809 	[OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
810 	[OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
811 	[OVS_KEY_ATTR_SKB_MARK] = sizeof(u32),
812 	[OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
813 	[OVS_KEY_ATTR_VLAN] = sizeof(__be16),
814 	[OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
815 	[OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
816 	[OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
817 	[OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
818 	[OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
819 	[OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
820 	[OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
821 	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
822 	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
823 };
824 
825 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
826 				  const struct nlattr *a[], u32 *attrs)
827 {
828 	const struct ovs_key_icmp *icmp_key;
829 	const struct ovs_key_tcp *tcp_key;
830 	const struct ovs_key_udp *udp_key;
831 
832 	switch (swkey->ip.proto) {
833 	case IPPROTO_TCP:
834 		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
835 			return -EINVAL;
836 		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
837 
838 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
839 		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
840 		swkey->ipv4.tp.src = tcp_key->tcp_src;
841 		swkey->ipv4.tp.dst = tcp_key->tcp_dst;
842 		break;
843 
844 	case IPPROTO_UDP:
845 		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
846 			return -EINVAL;
847 		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
848 
849 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
850 		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
851 		swkey->ipv4.tp.src = udp_key->udp_src;
852 		swkey->ipv4.tp.dst = udp_key->udp_dst;
853 		break;
854 
855 	case IPPROTO_ICMP:
856 		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
857 			return -EINVAL;
858 		*attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
859 
860 		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
861 		icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
862 		swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
863 		swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
864 		break;
865 	}
866 
867 	return 0;
868 }
869 
870 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
871 				  const struct nlattr *a[], u32 *attrs)
872 {
873 	const struct ovs_key_icmpv6 *icmpv6_key;
874 	const struct ovs_key_tcp *tcp_key;
875 	const struct ovs_key_udp *udp_key;
876 
877 	switch (swkey->ip.proto) {
878 	case IPPROTO_TCP:
879 		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
880 			return -EINVAL;
881 		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
882 
883 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
884 		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
885 		swkey->ipv6.tp.src = tcp_key->tcp_src;
886 		swkey->ipv6.tp.dst = tcp_key->tcp_dst;
887 		break;
888 
889 	case IPPROTO_UDP:
890 		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
891 			return -EINVAL;
892 		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
893 
894 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
895 		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
896 		swkey->ipv6.tp.src = udp_key->udp_src;
897 		swkey->ipv6.tp.dst = udp_key->udp_dst;
898 		break;
899 
900 	case IPPROTO_ICMPV6:
901 		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
902 			return -EINVAL;
903 		*attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
904 
905 		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
906 		icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
907 		swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
908 		swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
909 
910 		if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
911 		    swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
912 			const struct ovs_key_nd *nd_key;
913 
914 			if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
915 				return -EINVAL;
916 			*attrs &= ~(1 << OVS_KEY_ATTR_ND);
917 
918 			*key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
919 			nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
920 			memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
921 			       sizeof(swkey->ipv6.nd.target));
922 			memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
923 			memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
924 		}
925 		break;
926 	}
927 
928 	return 0;
929 }
930 
931 static int parse_flow_nlattrs(const struct nlattr *attr,
932 			      const struct nlattr *a[], u32 *attrsp)
933 {
934 	const struct nlattr *nla;
935 	u32 attrs;
936 	int rem;
937 
938 	attrs = 0;
939 	nla_for_each_nested(nla, attr, rem) {
940 		u16 type = nla_type(nla);
941 		int expected_len;
942 
943 		if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
944 			return -EINVAL;
945 
946 		expected_len = ovs_key_lens[type];
947 		if (nla_len(nla) != expected_len && expected_len != -1)
948 			return -EINVAL;
949 
950 		attrs |= 1 << type;
951 		a[type] = nla;
952 	}
953 	if (rem)
954 		return -EINVAL;
955 
956 	*attrsp = attrs;
957 	return 0;
958 }
959 
960 /**
961  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
962  * @swkey: receives the extracted flow key.
963  * @key_lenp: number of bytes used in @swkey.
964  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
965  * sequence.
966  */
967 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
968 		      const struct nlattr *attr)
969 {
970 	const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
971 	const struct ovs_key_ethernet *eth_key;
972 	int key_len;
973 	u32 attrs;
974 	int err;
975 
976 	memset(swkey, 0, sizeof(struct sw_flow_key));
977 	key_len = SW_FLOW_KEY_OFFSET(eth);
978 
979 	err = parse_flow_nlattrs(attr, a, &attrs);
980 	if (err)
981 		return err;
982 
983 	/* Metadata attributes. */
984 	if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
985 		swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
986 		attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
987 	}
988 	if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
989 		u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
990 		if (in_port >= DP_MAX_PORTS)
991 			return -EINVAL;
992 		swkey->phy.in_port = in_port;
993 		attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
994 	} else {
995 		swkey->phy.in_port = DP_MAX_PORTS;
996 	}
997 	if (attrs & (1 << OVS_KEY_ATTR_SKB_MARK)) {
998 		swkey->phy.skb_mark = nla_get_u32(a[OVS_KEY_ATTR_SKB_MARK]);
999 		attrs &= ~(1 << OVS_KEY_ATTR_SKB_MARK);
1000 	}
1001 
1002 	/* Data attributes. */
1003 	if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1004 		return -EINVAL;
1005 	attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1006 
1007 	eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1008 	memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1009 	memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1010 
1011 	if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1012 	    nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1013 		const struct nlattr *encap;
1014 		__be16 tci;
1015 
1016 		if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1017 			      (1 << OVS_KEY_ATTR_ETHERTYPE) |
1018 			      (1 << OVS_KEY_ATTR_ENCAP)))
1019 			return -EINVAL;
1020 
1021 		encap = a[OVS_KEY_ATTR_ENCAP];
1022 		tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1023 		if (tci & htons(VLAN_TAG_PRESENT)) {
1024 			swkey->eth.tci = tci;
1025 
1026 			err = parse_flow_nlattrs(encap, a, &attrs);
1027 			if (err)
1028 				return err;
1029 		} else if (!tci) {
1030 			/* Corner case for truncated 802.1Q header. */
1031 			if (nla_len(encap))
1032 				return -EINVAL;
1033 
1034 			swkey->eth.type = htons(ETH_P_8021Q);
1035 			*key_lenp = key_len;
1036 			return 0;
1037 		} else {
1038 			return -EINVAL;
1039 		}
1040 	}
1041 
1042 	if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1043 		swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1044 		if (ntohs(swkey->eth.type) < ETH_P_802_3_MIN)
1045 			return -EINVAL;
1046 		attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1047 	} else {
1048 		swkey->eth.type = htons(ETH_P_802_2);
1049 	}
1050 
1051 	if (swkey->eth.type == htons(ETH_P_IP)) {
1052 		const struct ovs_key_ipv4 *ipv4_key;
1053 
1054 		if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1055 			return -EINVAL;
1056 		attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1057 
1058 		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1059 		ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1060 		if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1061 			return -EINVAL;
1062 		swkey->ip.proto = ipv4_key->ipv4_proto;
1063 		swkey->ip.tos = ipv4_key->ipv4_tos;
1064 		swkey->ip.ttl = ipv4_key->ipv4_ttl;
1065 		swkey->ip.frag = ipv4_key->ipv4_frag;
1066 		swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1067 		swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1068 
1069 		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1070 			err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1071 			if (err)
1072 				return err;
1073 		}
1074 	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1075 		const struct ovs_key_ipv6 *ipv6_key;
1076 
1077 		if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1078 			return -EINVAL;
1079 		attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1080 
1081 		key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1082 		ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1083 		if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1084 			return -EINVAL;
1085 		swkey->ipv6.label = ipv6_key->ipv6_label;
1086 		swkey->ip.proto = ipv6_key->ipv6_proto;
1087 		swkey->ip.tos = ipv6_key->ipv6_tclass;
1088 		swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1089 		swkey->ip.frag = ipv6_key->ipv6_frag;
1090 		memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1091 		       sizeof(swkey->ipv6.addr.src));
1092 		memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1093 		       sizeof(swkey->ipv6.addr.dst));
1094 
1095 		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1096 			err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1097 			if (err)
1098 				return err;
1099 		}
1100 	} else if (swkey->eth.type == htons(ETH_P_ARP) ||
1101 		   swkey->eth.type == htons(ETH_P_RARP)) {
1102 		const struct ovs_key_arp *arp_key;
1103 
1104 		if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1105 			return -EINVAL;
1106 		attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1107 
1108 		key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1109 		arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1110 		swkey->ipv4.addr.src = arp_key->arp_sip;
1111 		swkey->ipv4.addr.dst = arp_key->arp_tip;
1112 		if (arp_key->arp_op & htons(0xff00))
1113 			return -EINVAL;
1114 		swkey->ip.proto = ntohs(arp_key->arp_op);
1115 		memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1116 		memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1117 	}
1118 
1119 	if (attrs)
1120 		return -EINVAL;
1121 	*key_lenp = key_len;
1122 
1123 	return 0;
1124 }
1125 
1126 /**
1127  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1128  * @flow: Receives extracted in_port, priority, tun_key and skb_mark.
1129  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1130  * sequence.
1131  *
1132  * This parses a series of Netlink attributes that form a flow key, which must
1133  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1134  * get the metadata, that is, the parts of the flow key that cannot be
1135  * extracted from the packet itself.
1136  */
1137 int ovs_flow_metadata_from_nlattrs(struct sw_flow *flow,
1138 				   const struct nlattr *attr)
1139 {
1140 	const struct nlattr *nla;
1141 	int rem;
1142 
1143 	flow->key.phy.in_port = DP_MAX_PORTS;
1144 	flow->key.phy.priority = 0;
1145 	flow->key.phy.skb_mark = 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 				flow->key.phy.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 				flow->key.phy.in_port = nla_get_u32(nla);
1163 				break;
1164 
1165 			case OVS_KEY_ATTR_SKB_MARK:
1166 				flow->key.phy.skb_mark = nla_get_u32(nla);
1167 				break;
1168 			}
1169 		}
1170 	}
1171 	if (rem)
1172 		return -EINVAL;
1173 	return 0;
1174 }
1175 
1176 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1177 {
1178 	struct ovs_key_ethernet *eth_key;
1179 	struct nlattr *nla, *encap;
1180 
1181 	if (swkey->phy.priority &&
1182 	    nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority))
1183 		goto nla_put_failure;
1184 
1185 	if (swkey->phy.in_port != DP_MAX_PORTS &&
1186 	    nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port))
1187 		goto nla_put_failure;
1188 
1189 	if (swkey->phy.skb_mark &&
1190 	    nla_put_u32(skb, OVS_KEY_ATTR_SKB_MARK, swkey->phy.skb_mark))
1191 		goto nla_put_failure;
1192 
1193 	nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1194 	if (!nla)
1195 		goto nla_put_failure;
1196 	eth_key = nla_data(nla);
1197 	memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1198 	memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1199 
1200 	if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1201 		if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q)) ||
1202 		    nla_put_be16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci))
1203 			goto nla_put_failure;
1204 		encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1205 		if (!swkey->eth.tci)
1206 			goto unencap;
1207 	} else {
1208 		encap = NULL;
1209 	}
1210 
1211 	if (swkey->eth.type == htons(ETH_P_802_2))
1212 		goto unencap;
1213 
1214 	if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type))
1215 		goto nla_put_failure;
1216 
1217 	if (swkey->eth.type == htons(ETH_P_IP)) {
1218 		struct ovs_key_ipv4 *ipv4_key;
1219 
1220 		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1221 		if (!nla)
1222 			goto nla_put_failure;
1223 		ipv4_key = nla_data(nla);
1224 		ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1225 		ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1226 		ipv4_key->ipv4_proto = swkey->ip.proto;
1227 		ipv4_key->ipv4_tos = swkey->ip.tos;
1228 		ipv4_key->ipv4_ttl = swkey->ip.ttl;
1229 		ipv4_key->ipv4_frag = swkey->ip.frag;
1230 	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1231 		struct ovs_key_ipv6 *ipv6_key;
1232 
1233 		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1234 		if (!nla)
1235 			goto nla_put_failure;
1236 		ipv6_key = nla_data(nla);
1237 		memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1238 				sizeof(ipv6_key->ipv6_src));
1239 		memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1240 				sizeof(ipv6_key->ipv6_dst));
1241 		ipv6_key->ipv6_label = swkey->ipv6.label;
1242 		ipv6_key->ipv6_proto = swkey->ip.proto;
1243 		ipv6_key->ipv6_tclass = swkey->ip.tos;
1244 		ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1245 		ipv6_key->ipv6_frag = swkey->ip.frag;
1246 	} else if (swkey->eth.type == htons(ETH_P_ARP) ||
1247 		   swkey->eth.type == htons(ETH_P_RARP)) {
1248 		struct ovs_key_arp *arp_key;
1249 
1250 		nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1251 		if (!nla)
1252 			goto nla_put_failure;
1253 		arp_key = nla_data(nla);
1254 		memset(arp_key, 0, sizeof(struct ovs_key_arp));
1255 		arp_key->arp_sip = swkey->ipv4.addr.src;
1256 		arp_key->arp_tip = swkey->ipv4.addr.dst;
1257 		arp_key->arp_op = htons(swkey->ip.proto);
1258 		memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1259 		memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1260 	}
1261 
1262 	if ((swkey->eth.type == htons(ETH_P_IP) ||
1263 	     swkey->eth.type == htons(ETH_P_IPV6)) &&
1264 	     swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1265 
1266 		if (swkey->ip.proto == IPPROTO_TCP) {
1267 			struct ovs_key_tcp *tcp_key;
1268 
1269 			nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1270 			if (!nla)
1271 				goto nla_put_failure;
1272 			tcp_key = nla_data(nla);
1273 			if (swkey->eth.type == htons(ETH_P_IP)) {
1274 				tcp_key->tcp_src = swkey->ipv4.tp.src;
1275 				tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1276 			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1277 				tcp_key->tcp_src = swkey->ipv6.tp.src;
1278 				tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1279 			}
1280 		} else if (swkey->ip.proto == IPPROTO_UDP) {
1281 			struct ovs_key_udp *udp_key;
1282 
1283 			nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1284 			if (!nla)
1285 				goto nla_put_failure;
1286 			udp_key = nla_data(nla);
1287 			if (swkey->eth.type == htons(ETH_P_IP)) {
1288 				udp_key->udp_src = swkey->ipv4.tp.src;
1289 				udp_key->udp_dst = swkey->ipv4.tp.dst;
1290 			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1291 				udp_key->udp_src = swkey->ipv6.tp.src;
1292 				udp_key->udp_dst = swkey->ipv6.tp.dst;
1293 			}
1294 		} else if (swkey->eth.type == htons(ETH_P_IP) &&
1295 			   swkey->ip.proto == IPPROTO_ICMP) {
1296 			struct ovs_key_icmp *icmp_key;
1297 
1298 			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1299 			if (!nla)
1300 				goto nla_put_failure;
1301 			icmp_key = nla_data(nla);
1302 			icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1303 			icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1304 		} else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1305 			   swkey->ip.proto == IPPROTO_ICMPV6) {
1306 			struct ovs_key_icmpv6 *icmpv6_key;
1307 
1308 			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1309 						sizeof(*icmpv6_key));
1310 			if (!nla)
1311 				goto nla_put_failure;
1312 			icmpv6_key = nla_data(nla);
1313 			icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1314 			icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1315 
1316 			if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1317 			    icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1318 				struct ovs_key_nd *nd_key;
1319 
1320 				nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1321 				if (!nla)
1322 					goto nla_put_failure;
1323 				nd_key = nla_data(nla);
1324 				memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1325 							sizeof(nd_key->nd_target));
1326 				memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1327 				memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1328 			}
1329 		}
1330 	}
1331 
1332 unencap:
1333 	if (encap)
1334 		nla_nest_end(skb, encap);
1335 
1336 	return 0;
1337 
1338 nla_put_failure:
1339 	return -EMSGSIZE;
1340 }
1341 
1342 /* Initializes the flow module.
1343  * Returns zero if successful or a negative error code. */
1344 int ovs_flow_init(void)
1345 {
1346 	flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1347 					0, NULL);
1348 	if (flow_cache == NULL)
1349 		return -ENOMEM;
1350 
1351 	return 0;
1352 }
1353 
1354 /* Uninitializes the flow module. */
1355 void ovs_flow_exit(void)
1356 {
1357 	kmem_cache_destroy(flow_cache);
1358 }
1359