flow.c revision 42415c90ceaf50c792e29823e359463bc6d4ee05
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/ip_tunnels.h>
44#include <net/ipv6.h>
45#include <net/ndisc.h>
46
47static struct kmem_cache *flow_cache;
48
49static int check_header(struct sk_buff *skb, int len)
50{
51	if (unlikely(skb->len < len))
52		return -EINVAL;
53	if (unlikely(!pskb_may_pull(skb, len)))
54		return -ENOMEM;
55	return 0;
56}
57
58static bool arphdr_ok(struct sk_buff *skb)
59{
60	return pskb_may_pull(skb, skb_network_offset(skb) +
61				  sizeof(struct arp_eth_header));
62}
63
64static int check_iphdr(struct sk_buff *skb)
65{
66	unsigned int nh_ofs = skb_network_offset(skb);
67	unsigned int ip_len;
68	int err;
69
70	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
71	if (unlikely(err))
72		return err;
73
74	ip_len = ip_hdrlen(skb);
75	if (unlikely(ip_len < sizeof(struct iphdr) ||
76		     skb->len < nh_ofs + ip_len))
77		return -EINVAL;
78
79	skb_set_transport_header(skb, nh_ofs + ip_len);
80	return 0;
81}
82
83static bool tcphdr_ok(struct sk_buff *skb)
84{
85	int th_ofs = skb_transport_offset(skb);
86	int tcp_len;
87
88	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
89		return false;
90
91	tcp_len = tcp_hdrlen(skb);
92	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
93		     skb->len < th_ofs + tcp_len))
94		return false;
95
96	return true;
97}
98
99static bool udphdr_ok(struct sk_buff *skb)
100{
101	return pskb_may_pull(skb, skb_transport_offset(skb) +
102				  sizeof(struct udphdr));
103}
104
105static bool icmphdr_ok(struct sk_buff *skb)
106{
107	return pskb_may_pull(skb, skb_transport_offset(skb) +
108				  sizeof(struct icmphdr));
109}
110
111u64 ovs_flow_used_time(unsigned long flow_jiffies)
112{
113	struct timespec cur_ts;
114	u64 cur_ms, idle_ms;
115
116	ktime_get_ts(&cur_ts);
117	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
118	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
119		 cur_ts.tv_nsec / NSEC_PER_MSEC;
120
121	return cur_ms - idle_ms;
122}
123
124#define SW_FLOW_KEY_OFFSET(field)		\
125	(offsetof(struct sw_flow_key, field) +	\
126	 FIELD_SIZEOF(struct sw_flow_key, field))
127
128static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
129			 int *key_lenp)
130{
131	unsigned int nh_ofs = skb_network_offset(skb);
132	unsigned int nh_len;
133	int payload_ofs;
134	struct ipv6hdr *nh;
135	uint8_t nexthdr;
136	__be16 frag_off;
137	int err;
138
139	*key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
140
141	err = check_header(skb, nh_ofs + sizeof(*nh));
142	if (unlikely(err))
143		return err;
144
145	nh = ipv6_hdr(skb);
146	nexthdr = nh->nexthdr;
147	payload_ofs = (u8 *)(nh + 1) - skb->data;
148
149	key->ip.proto = NEXTHDR_NONE;
150	key->ip.tos = ipv6_get_dsfield(nh);
151	key->ip.ttl = nh->hop_limit;
152	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
153	key->ipv6.addr.src = nh->saddr;
154	key->ipv6.addr.dst = nh->daddr;
155
156	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
157	if (unlikely(payload_ofs < 0))
158		return -EINVAL;
159
160	if (frag_off) {
161		if (frag_off & htons(~0x7))
162			key->ip.frag = OVS_FRAG_TYPE_LATER;
163		else
164			key->ip.frag = OVS_FRAG_TYPE_FIRST;
165	}
166
167	nh_len = payload_ofs - nh_ofs;
168	skb_set_transport_header(skb, nh_ofs + nh_len);
169	key->ip.proto = nexthdr;
170	return nh_len;
171}
172
173static bool icmp6hdr_ok(struct sk_buff *skb)
174{
175	return pskb_may_pull(skb, skb_transport_offset(skb) +
176				  sizeof(struct icmp6hdr));
177}
178
179#define TCP_FLAGS_OFFSET 13
180#define TCP_FLAG_MASK 0x3f
181
182void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
183{
184	u8 tcp_flags = 0;
185
186	if ((flow->key.eth.type == htons(ETH_P_IP) ||
187	     flow->key.eth.type == htons(ETH_P_IPV6)) &&
188	    flow->key.ip.proto == IPPROTO_TCP &&
189	    likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
190		u8 *tcp = (u8 *)tcp_hdr(skb);
191		tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
192	}
193
194	spin_lock(&flow->lock);
195	flow->used = jiffies;
196	flow->packet_count++;
197	flow->byte_count += skb->len;
198	flow->tcp_flags |= tcp_flags;
199	spin_unlock(&flow->lock);
200}
201
202struct sw_flow_actions *ovs_flow_actions_alloc(int size)
203{
204	struct sw_flow_actions *sfa;
205
206	if (size > MAX_ACTIONS_BUFSIZE)
207		return ERR_PTR(-EINVAL);
208
209	sfa = kmalloc(sizeof(*sfa) + size, GFP_KERNEL);
210	if (!sfa)
211		return ERR_PTR(-ENOMEM);
212
213	sfa->actions_len = 0;
214	return sfa;
215}
216
217struct sw_flow *ovs_flow_alloc(void)
218{
219	struct sw_flow *flow;
220
221	flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
222	if (!flow)
223		return ERR_PTR(-ENOMEM);
224
225	spin_lock_init(&flow->lock);
226	flow->sf_acts = NULL;
227
228	return flow;
229}
230
231static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
232{
233	hash = jhash_1word(hash, table->hash_seed);
234	return flex_array_get(table->buckets,
235				(hash & (table->n_buckets - 1)));
236}
237
238static struct flex_array *alloc_buckets(unsigned int n_buckets)
239{
240	struct flex_array *buckets;
241	int i, err;
242
243	buckets = flex_array_alloc(sizeof(struct hlist_head),
244				   n_buckets, GFP_KERNEL);
245	if (!buckets)
246		return NULL;
247
248	err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
249	if (err) {
250		flex_array_free(buckets);
251		return NULL;
252	}
253
254	for (i = 0; i < n_buckets; i++)
255		INIT_HLIST_HEAD((struct hlist_head *)
256					flex_array_get(buckets, i));
257
258	return buckets;
259}
260
261static void free_buckets(struct flex_array *buckets)
262{
263	flex_array_free(buckets);
264}
265
266struct flow_table *ovs_flow_tbl_alloc(int new_size)
267{
268	struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
269
270	if (!table)
271		return NULL;
272
273	table->buckets = alloc_buckets(new_size);
274
275	if (!table->buckets) {
276		kfree(table);
277		return NULL;
278	}
279	table->n_buckets = new_size;
280	table->count = 0;
281	table->node_ver = 0;
282	table->keep_flows = false;
283	get_random_bytes(&table->hash_seed, sizeof(u32));
284
285	return table;
286}
287
288void ovs_flow_tbl_destroy(struct flow_table *table)
289{
290	int i;
291
292	if (!table)
293		return;
294
295	if (table->keep_flows)
296		goto skip_flows;
297
298	for (i = 0; i < table->n_buckets; i++) {
299		struct sw_flow *flow;
300		struct hlist_head *head = flex_array_get(table->buckets, i);
301		struct hlist_node *n;
302		int ver = table->node_ver;
303
304		hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
305			hlist_del_rcu(&flow->hash_node[ver]);
306			ovs_flow_free(flow);
307		}
308	}
309
310skip_flows:
311	free_buckets(table->buckets);
312	kfree(table);
313}
314
315static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
316{
317	struct flow_table *table = container_of(rcu, struct flow_table, rcu);
318
319	ovs_flow_tbl_destroy(table);
320}
321
322void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
323{
324	if (!table)
325		return;
326
327	call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
328}
329
330struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
331{
332	struct sw_flow *flow;
333	struct hlist_head *head;
334	int ver;
335	int i;
336
337	ver = table->node_ver;
338	while (*bucket < table->n_buckets) {
339		i = 0;
340		head = flex_array_get(table->buckets, *bucket);
341		hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
342			if (i < *last) {
343				i++;
344				continue;
345			}
346			*last = i + 1;
347			return flow;
348		}
349		(*bucket)++;
350		*last = 0;
351	}
352
353	return NULL;
354}
355
356static void __flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
357{
358	struct hlist_head *head;
359	head = find_bucket(table, flow->hash);
360	hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
361	table->count++;
362}
363
364static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
365{
366	int old_ver;
367	int i;
368
369	old_ver = old->node_ver;
370	new->node_ver = !old_ver;
371
372	/* Insert in new table. */
373	for (i = 0; i < old->n_buckets; i++) {
374		struct sw_flow *flow;
375		struct hlist_head *head;
376
377		head = flex_array_get(old->buckets, i);
378
379		hlist_for_each_entry(flow, head, hash_node[old_ver])
380			__flow_tbl_insert(new, flow);
381	}
382	old->keep_flows = true;
383}
384
385static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
386{
387	struct flow_table *new_table;
388
389	new_table = ovs_flow_tbl_alloc(n_buckets);
390	if (!new_table)
391		return ERR_PTR(-ENOMEM);
392
393	flow_table_copy_flows(table, new_table);
394
395	return new_table;
396}
397
398struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
399{
400	return __flow_tbl_rehash(table, table->n_buckets);
401}
402
403struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
404{
405	return __flow_tbl_rehash(table, table->n_buckets * 2);
406}
407
408void ovs_flow_free(struct sw_flow *flow)
409{
410	if (unlikely(!flow))
411		return;
412
413	kfree((struct sf_flow_acts __force *)flow->sf_acts);
414	kmem_cache_free(flow_cache, flow);
415}
416
417/* RCU callback used by ovs_flow_deferred_free. */
418static void rcu_free_flow_callback(struct rcu_head *rcu)
419{
420	struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
421
422	ovs_flow_free(flow);
423}
424
425/* Schedules 'flow' to be freed after the next RCU grace period.
426 * The caller must hold rcu_read_lock for this to be sensible. */
427void ovs_flow_deferred_free(struct sw_flow *flow)
428{
429	call_rcu(&flow->rcu, rcu_free_flow_callback);
430}
431
432/* Schedules 'sf_acts' to be freed after the next RCU grace period.
433 * The caller must hold rcu_read_lock for this to be sensible. */
434void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
435{
436	kfree_rcu(sf_acts, rcu);
437}
438
439static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
440{
441	struct qtag_prefix {
442		__be16 eth_type; /* ETH_P_8021Q */
443		__be16 tci;
444	};
445	struct qtag_prefix *qp;
446
447	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
448		return 0;
449
450	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
451					 sizeof(__be16))))
452		return -ENOMEM;
453
454	qp = (struct qtag_prefix *) skb->data;
455	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
456	__skb_pull(skb, sizeof(struct qtag_prefix));
457
458	return 0;
459}
460
461static __be16 parse_ethertype(struct sk_buff *skb)
462{
463	struct llc_snap_hdr {
464		u8  dsap;  /* Always 0xAA */
465		u8  ssap;  /* Always 0xAA */
466		u8  ctrl;
467		u8  oui[3];
468		__be16 ethertype;
469	};
470	struct llc_snap_hdr *llc;
471	__be16 proto;
472
473	proto = *(__be16 *) skb->data;
474	__skb_pull(skb, sizeof(__be16));
475
476	if (ntohs(proto) >= ETH_P_802_3_MIN)
477		return proto;
478
479	if (skb->len < sizeof(struct llc_snap_hdr))
480		return htons(ETH_P_802_2);
481
482	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
483		return htons(0);
484
485	llc = (struct llc_snap_hdr *) skb->data;
486	if (llc->dsap != LLC_SAP_SNAP ||
487	    llc->ssap != LLC_SAP_SNAP ||
488	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
489		return htons(ETH_P_802_2);
490
491	__skb_pull(skb, sizeof(struct llc_snap_hdr));
492
493	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
494		return llc->ethertype;
495
496	return htons(ETH_P_802_2);
497}
498
499static 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
571invalid:
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
576out:
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->eth.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->eth.type values it is left untouched.
604 */
605int 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	if (OVS_CB(skb)->tun_key)
616		memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
617	key->phy.in_port = in_port;
618	key->phy.skb_mark = skb->mark;
619
620	skb_reset_mac_header(skb);
621
622	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
623	 * header in the linear data area.
624	 */
625	eth = eth_hdr(skb);
626	memcpy(key->eth.src, eth->h_source, ETH_ALEN);
627	memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
628
629	__skb_pull(skb, 2 * ETH_ALEN);
630	/* We are going to push all headers that we pull, so no need to
631	 * update skb->csum here.
632	 */
633
634	if (vlan_tx_tag_present(skb))
635		key->eth.tci = htons(skb->vlan_tci);
636	else if (eth->h_proto == htons(ETH_P_8021Q))
637		if (unlikely(parse_vlan(skb, key)))
638			return -ENOMEM;
639
640	key->eth.type = parse_ethertype(skb);
641	if (unlikely(key->eth.type == htons(0)))
642		return -ENOMEM;
643
644	skb_reset_network_header(skb);
645	__skb_push(skb, skb->data - skb_mac_header(skb));
646
647	/* Network layer. */
648	if (key->eth.type == htons(ETH_P_IP)) {
649		struct iphdr *nh;
650		__be16 offset;
651
652		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
653
654		error = check_iphdr(skb);
655		if (unlikely(error)) {
656			if (error == -EINVAL) {
657				skb->transport_header = skb->network_header;
658				error = 0;
659			}
660			goto out;
661		}
662
663		nh = ip_hdr(skb);
664		key->ipv4.addr.src = nh->saddr;
665		key->ipv4.addr.dst = nh->daddr;
666
667		key->ip.proto = nh->protocol;
668		key->ip.tos = nh->tos;
669		key->ip.ttl = nh->ttl;
670
671		offset = nh->frag_off & htons(IP_OFFSET);
672		if (offset) {
673			key->ip.frag = OVS_FRAG_TYPE_LATER;
674			goto out;
675		}
676		if (nh->frag_off & htons(IP_MF) ||
677			 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
678			key->ip.frag = OVS_FRAG_TYPE_FIRST;
679
680		/* Transport layer. */
681		if (key->ip.proto == IPPROTO_TCP) {
682			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
683			if (tcphdr_ok(skb)) {
684				struct tcphdr *tcp = tcp_hdr(skb);
685				key->ipv4.tp.src = tcp->source;
686				key->ipv4.tp.dst = tcp->dest;
687			}
688		} else if (key->ip.proto == IPPROTO_UDP) {
689			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
690			if (udphdr_ok(skb)) {
691				struct udphdr *udp = udp_hdr(skb);
692				key->ipv4.tp.src = udp->source;
693				key->ipv4.tp.dst = udp->dest;
694			}
695		} else if (key->ip.proto == IPPROTO_ICMP) {
696			key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
697			if (icmphdr_ok(skb)) {
698				struct icmphdr *icmp = icmp_hdr(skb);
699				/* The ICMP type and code fields use the 16-bit
700				 * transport port fields, so we need to store
701				 * them in 16-bit network byte order. */
702				key->ipv4.tp.src = htons(icmp->type);
703				key->ipv4.tp.dst = htons(icmp->code);
704			}
705		}
706
707	} else if ((key->eth.type == htons(ETH_P_ARP) ||
708		   key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
709		struct arp_eth_header *arp;
710
711		arp = (struct arp_eth_header *)skb_network_header(skb);
712
713		if (arp->ar_hrd == htons(ARPHRD_ETHER)
714				&& arp->ar_pro == htons(ETH_P_IP)
715				&& arp->ar_hln == ETH_ALEN
716				&& arp->ar_pln == 4) {
717
718			/* We only match on the lower 8 bits of the opcode. */
719			if (ntohs(arp->ar_op) <= 0xff)
720				key->ip.proto = ntohs(arp->ar_op);
721			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
722			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
723			memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
724			memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
725			key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
726		}
727	} else if (key->eth.type == htons(ETH_P_IPV6)) {
728		int nh_len;             /* IPv6 Header + Extensions */
729
730		nh_len = parse_ipv6hdr(skb, key, &key_len);
731		if (unlikely(nh_len < 0)) {
732			if (nh_len == -EINVAL)
733				skb->transport_header = skb->network_header;
734			else
735				error = nh_len;
736			goto out;
737		}
738
739		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
740			goto out;
741		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
742			key->ip.frag = OVS_FRAG_TYPE_FIRST;
743
744		/* Transport layer. */
745		if (key->ip.proto == NEXTHDR_TCP) {
746			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
747			if (tcphdr_ok(skb)) {
748				struct tcphdr *tcp = tcp_hdr(skb);
749				key->ipv6.tp.src = tcp->source;
750				key->ipv6.tp.dst = tcp->dest;
751			}
752		} else if (key->ip.proto == NEXTHDR_UDP) {
753			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
754			if (udphdr_ok(skb)) {
755				struct udphdr *udp = udp_hdr(skb);
756				key->ipv6.tp.src = udp->source;
757				key->ipv6.tp.dst = udp->dest;
758			}
759		} else if (key->ip.proto == NEXTHDR_ICMP) {
760			key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
761			if (icmp6hdr_ok(skb)) {
762				error = parse_icmpv6(skb, key, &key_len, nh_len);
763				if (error < 0)
764					goto out;
765			}
766		}
767	}
768
769out:
770	*key_lenp = key_len;
771	return error;
772}
773
774static u32 ovs_flow_hash(const struct sw_flow_key *key, int key_start, int key_len)
775{
776	return jhash2((u32 *)((u8 *)key + key_start),
777		      DIV_ROUND_UP(key_len - key_start, sizeof(u32)), 0);
778}
779
780static int flow_key_start(struct sw_flow_key *key)
781{
782	if (key->tun_key.ipv4_dst)
783		return 0;
784	else
785		return offsetof(struct sw_flow_key, phy);
786}
787
788struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
789				struct sw_flow_key *key, int key_len)
790{
791	struct sw_flow *flow;
792	struct hlist_head *head;
793	u8 *_key;
794	int key_start;
795	u32 hash;
796
797	key_start = flow_key_start(key);
798	hash = ovs_flow_hash(key, key_start, key_len);
799
800	_key = (u8 *) key + key_start;
801	head = find_bucket(table, hash);
802	hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
803
804		if (flow->hash == hash &&
805		    !memcmp((u8 *)&flow->key + key_start, _key, key_len - key_start)) {
806			return flow;
807		}
808	}
809	return NULL;
810}
811
812void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,
813			 struct sw_flow_key *key, int key_len)
814{
815	flow->hash = ovs_flow_hash(key, flow_key_start(key), key_len);
816	memcpy(&flow->key, key, sizeof(flow->key));
817	__flow_tbl_insert(table, flow);
818}
819
820void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
821{
822	BUG_ON(table->count == 0);
823	hlist_del_rcu(&flow->hash_node[table->node_ver]);
824	table->count--;
825}
826
827/* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
828const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
829	[OVS_KEY_ATTR_ENCAP] = -1,
830	[OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
831	[OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
832	[OVS_KEY_ATTR_SKB_MARK] = sizeof(u32),
833	[OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
834	[OVS_KEY_ATTR_VLAN] = sizeof(__be16),
835	[OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
836	[OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
837	[OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
838	[OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
839	[OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
840	[OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
841	[OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
842	[OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
843	[OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
844	[OVS_KEY_ATTR_TUNNEL] = -1,
845};
846
847static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
848				  const struct nlattr *a[], u32 *attrs)
849{
850	const struct ovs_key_icmp *icmp_key;
851	const struct ovs_key_tcp *tcp_key;
852	const struct ovs_key_udp *udp_key;
853
854	switch (swkey->ip.proto) {
855	case IPPROTO_TCP:
856		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
857			return -EINVAL;
858		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
859
860		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
861		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
862		swkey->ipv4.tp.src = tcp_key->tcp_src;
863		swkey->ipv4.tp.dst = tcp_key->tcp_dst;
864		break;
865
866	case IPPROTO_UDP:
867		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
868			return -EINVAL;
869		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
870
871		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
872		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
873		swkey->ipv4.tp.src = udp_key->udp_src;
874		swkey->ipv4.tp.dst = udp_key->udp_dst;
875		break;
876
877	case IPPROTO_ICMP:
878		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
879			return -EINVAL;
880		*attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
881
882		*key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
883		icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
884		swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
885		swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
886		break;
887	}
888
889	return 0;
890}
891
892static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
893				  const struct nlattr *a[], u32 *attrs)
894{
895	const struct ovs_key_icmpv6 *icmpv6_key;
896	const struct ovs_key_tcp *tcp_key;
897	const struct ovs_key_udp *udp_key;
898
899	switch (swkey->ip.proto) {
900	case IPPROTO_TCP:
901		if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
902			return -EINVAL;
903		*attrs &= ~(1 << OVS_KEY_ATTR_TCP);
904
905		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
906		tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
907		swkey->ipv6.tp.src = tcp_key->tcp_src;
908		swkey->ipv6.tp.dst = tcp_key->tcp_dst;
909		break;
910
911	case IPPROTO_UDP:
912		if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
913			return -EINVAL;
914		*attrs &= ~(1 << OVS_KEY_ATTR_UDP);
915
916		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
917		udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
918		swkey->ipv6.tp.src = udp_key->udp_src;
919		swkey->ipv6.tp.dst = udp_key->udp_dst;
920		break;
921
922	case IPPROTO_ICMPV6:
923		if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
924			return -EINVAL;
925		*attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
926
927		*key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
928		icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
929		swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
930		swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
931
932		if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
933		    swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
934			const struct ovs_key_nd *nd_key;
935
936			if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
937				return -EINVAL;
938			*attrs &= ~(1 << OVS_KEY_ATTR_ND);
939
940			*key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
941			nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
942			memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
943			       sizeof(swkey->ipv6.nd.target));
944			memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
945			memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
946		}
947		break;
948	}
949
950	return 0;
951}
952
953static int parse_flow_nlattrs(const struct nlattr *attr,
954			      const struct nlattr *a[], u32 *attrsp)
955{
956	const struct nlattr *nla;
957	u32 attrs;
958	int rem;
959
960	attrs = 0;
961	nla_for_each_nested(nla, attr, rem) {
962		u16 type = nla_type(nla);
963		int expected_len;
964
965		if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
966			return -EINVAL;
967
968		expected_len = ovs_key_lens[type];
969		if (nla_len(nla) != expected_len && expected_len != -1)
970			return -EINVAL;
971
972		attrs |= 1 << type;
973		a[type] = nla;
974	}
975	if (rem)
976		return -EINVAL;
977
978	*attrsp = attrs;
979	return 0;
980}
981
982int ovs_ipv4_tun_from_nlattr(const struct nlattr *attr,
983			     struct ovs_key_ipv4_tunnel *tun_key)
984{
985	struct nlattr *a;
986	int rem;
987	bool ttl = false;
988
989	memset(tun_key, 0, sizeof(*tun_key));
990
991	nla_for_each_nested(a, attr, rem) {
992		int type = nla_type(a);
993		static const u32 ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
994			[OVS_TUNNEL_KEY_ATTR_ID] = sizeof(u64),
995			[OVS_TUNNEL_KEY_ATTR_IPV4_SRC] = sizeof(u32),
996			[OVS_TUNNEL_KEY_ATTR_IPV4_DST] = sizeof(u32),
997			[OVS_TUNNEL_KEY_ATTR_TOS] = 1,
998			[OVS_TUNNEL_KEY_ATTR_TTL] = 1,
999			[OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT] = 0,
1000			[OVS_TUNNEL_KEY_ATTR_CSUM] = 0,
1001		};
1002
1003		if (type > OVS_TUNNEL_KEY_ATTR_MAX ||
1004			ovs_tunnel_key_lens[type] != nla_len(a))
1005			return -EINVAL;
1006
1007		switch (type) {
1008		case OVS_TUNNEL_KEY_ATTR_ID:
1009			tun_key->tun_id = nla_get_be64(a);
1010			tun_key->tun_flags |= TUNNEL_KEY;
1011			break;
1012		case OVS_TUNNEL_KEY_ATTR_IPV4_SRC:
1013			tun_key->ipv4_src = nla_get_be32(a);
1014			break;
1015		case OVS_TUNNEL_KEY_ATTR_IPV4_DST:
1016			tun_key->ipv4_dst = nla_get_be32(a);
1017			break;
1018		case OVS_TUNNEL_KEY_ATTR_TOS:
1019			tun_key->ipv4_tos = nla_get_u8(a);
1020			break;
1021		case OVS_TUNNEL_KEY_ATTR_TTL:
1022			tun_key->ipv4_ttl = nla_get_u8(a);
1023			ttl = true;
1024			break;
1025		case OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT:
1026			tun_key->tun_flags |= TUNNEL_DONT_FRAGMENT;
1027			break;
1028		case OVS_TUNNEL_KEY_ATTR_CSUM:
1029			tun_key->tun_flags |= TUNNEL_CSUM;
1030			break;
1031		default:
1032			return -EINVAL;
1033
1034		}
1035	}
1036	if (rem > 0)
1037		return -EINVAL;
1038
1039	if (!tun_key->ipv4_dst)
1040		return -EINVAL;
1041
1042	if (!ttl)
1043		return -EINVAL;
1044
1045	return 0;
1046}
1047
1048int ovs_ipv4_tun_to_nlattr(struct sk_buff *skb,
1049			   const struct ovs_key_ipv4_tunnel *tun_key)
1050{
1051	struct nlattr *nla;
1052
1053	nla = nla_nest_start(skb, OVS_KEY_ATTR_TUNNEL);
1054	if (!nla)
1055		return -EMSGSIZE;
1056
1057	if (tun_key->tun_flags & TUNNEL_KEY &&
1058	    nla_put_be64(skb, OVS_TUNNEL_KEY_ATTR_ID, tun_key->tun_id))
1059		return -EMSGSIZE;
1060	if (tun_key->ipv4_src &&
1061	    nla_put_be32(skb, OVS_TUNNEL_KEY_ATTR_IPV4_SRC, tun_key->ipv4_src))
1062		return -EMSGSIZE;
1063	if (nla_put_be32(skb, OVS_TUNNEL_KEY_ATTR_IPV4_DST, tun_key->ipv4_dst))
1064		return -EMSGSIZE;
1065	if (tun_key->ipv4_tos &&
1066	    nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TOS, tun_key->ipv4_tos))
1067		return -EMSGSIZE;
1068	if (nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TTL, tun_key->ipv4_ttl))
1069		return -EMSGSIZE;
1070	if ((tun_key->tun_flags & TUNNEL_DONT_FRAGMENT) &&
1071		nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT))
1072		return -EMSGSIZE;
1073	if ((tun_key->tun_flags & TUNNEL_CSUM) &&
1074		nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_CSUM))
1075		return -EMSGSIZE;
1076
1077	nla_nest_end(skb, nla);
1078	return 0;
1079}
1080
1081/**
1082 * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
1083 * @swkey: receives the extracted flow key.
1084 * @key_lenp: number of bytes used in @swkey.
1085 * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1086 * sequence.
1087 */
1088int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
1089		      const struct nlattr *attr)
1090{
1091	const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
1092	const struct ovs_key_ethernet *eth_key;
1093	int key_len;
1094	u32 attrs;
1095	int err;
1096
1097	memset(swkey, 0, sizeof(struct sw_flow_key));
1098	key_len = SW_FLOW_KEY_OFFSET(eth);
1099
1100	err = parse_flow_nlattrs(attr, a, &attrs);
1101	if (err)
1102		return err;
1103
1104	/* Metadata attributes. */
1105	if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
1106		swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
1107		attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
1108	}
1109	if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
1110		u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
1111		if (in_port >= DP_MAX_PORTS)
1112			return -EINVAL;
1113		swkey->phy.in_port = in_port;
1114		attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1115	} else {
1116		swkey->phy.in_port = DP_MAX_PORTS;
1117	}
1118	if (attrs & (1 << OVS_KEY_ATTR_SKB_MARK)) {
1119		swkey->phy.skb_mark = nla_get_u32(a[OVS_KEY_ATTR_SKB_MARK]);
1120		attrs &= ~(1 << OVS_KEY_ATTR_SKB_MARK);
1121	}
1122
1123	if (attrs & (1 << OVS_KEY_ATTR_TUNNEL)) {
1124		err = ovs_ipv4_tun_from_nlattr(a[OVS_KEY_ATTR_TUNNEL], &swkey->tun_key);
1125		if (err)
1126			return err;
1127
1128		attrs &= ~(1 << OVS_KEY_ATTR_TUNNEL);
1129	}
1130
1131	/* Data attributes. */
1132	if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1133		return -EINVAL;
1134	attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1135
1136	eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1137	memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1138	memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1139
1140	if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1141	    nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1142		const struct nlattr *encap;
1143		__be16 tci;
1144
1145		if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1146			      (1 << OVS_KEY_ATTR_ETHERTYPE) |
1147			      (1 << OVS_KEY_ATTR_ENCAP)))
1148			return -EINVAL;
1149
1150		encap = a[OVS_KEY_ATTR_ENCAP];
1151		tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1152		if (tci & htons(VLAN_TAG_PRESENT)) {
1153			swkey->eth.tci = tci;
1154
1155			err = parse_flow_nlattrs(encap, a, &attrs);
1156			if (err)
1157				return err;
1158		} else if (!tci) {
1159			/* Corner case for truncated 802.1Q header. */
1160			if (nla_len(encap))
1161				return -EINVAL;
1162
1163			swkey->eth.type = htons(ETH_P_8021Q);
1164			*key_lenp = key_len;
1165			return 0;
1166		} else {
1167			return -EINVAL;
1168		}
1169	}
1170
1171	if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1172		swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1173		if (ntohs(swkey->eth.type) < ETH_P_802_3_MIN)
1174			return -EINVAL;
1175		attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1176	} else {
1177		swkey->eth.type = htons(ETH_P_802_2);
1178	}
1179
1180	if (swkey->eth.type == htons(ETH_P_IP)) {
1181		const struct ovs_key_ipv4 *ipv4_key;
1182
1183		if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1184			return -EINVAL;
1185		attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1186
1187		key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1188		ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1189		if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1190			return -EINVAL;
1191		swkey->ip.proto = ipv4_key->ipv4_proto;
1192		swkey->ip.tos = ipv4_key->ipv4_tos;
1193		swkey->ip.ttl = ipv4_key->ipv4_ttl;
1194		swkey->ip.frag = ipv4_key->ipv4_frag;
1195		swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1196		swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1197
1198		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1199			err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1200			if (err)
1201				return err;
1202		}
1203	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1204		const struct ovs_key_ipv6 *ipv6_key;
1205
1206		if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1207			return -EINVAL;
1208		attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1209
1210		key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1211		ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1212		if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1213			return -EINVAL;
1214		swkey->ipv6.label = ipv6_key->ipv6_label;
1215		swkey->ip.proto = ipv6_key->ipv6_proto;
1216		swkey->ip.tos = ipv6_key->ipv6_tclass;
1217		swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1218		swkey->ip.frag = ipv6_key->ipv6_frag;
1219		memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1220		       sizeof(swkey->ipv6.addr.src));
1221		memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1222		       sizeof(swkey->ipv6.addr.dst));
1223
1224		if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1225			err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1226			if (err)
1227				return err;
1228		}
1229	} else if (swkey->eth.type == htons(ETH_P_ARP) ||
1230		   swkey->eth.type == htons(ETH_P_RARP)) {
1231		const struct ovs_key_arp *arp_key;
1232
1233		if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1234			return -EINVAL;
1235		attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1236
1237		key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1238		arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1239		swkey->ipv4.addr.src = arp_key->arp_sip;
1240		swkey->ipv4.addr.dst = arp_key->arp_tip;
1241		if (arp_key->arp_op & htons(0xff00))
1242			return -EINVAL;
1243		swkey->ip.proto = ntohs(arp_key->arp_op);
1244		memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1245		memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1246	}
1247
1248	if (attrs)
1249		return -EINVAL;
1250	*key_lenp = key_len;
1251
1252	return 0;
1253}
1254
1255/**
1256 * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1257 * @flow: Receives extracted in_port, priority, tun_key and skb_mark.
1258 * @key_len: Length of key in @flow.  Used for calculating flow hash.
1259 * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1260 * sequence.
1261 *
1262 * This parses a series of Netlink attributes that form a flow key, which must
1263 * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1264 * get the metadata, that is, the parts of the flow key that cannot be
1265 * extracted from the packet itself.
1266 */
1267int ovs_flow_metadata_from_nlattrs(struct sw_flow *flow, int key_len,
1268				   const struct nlattr *attr)
1269{
1270	struct ovs_key_ipv4_tunnel *tun_key = &flow->key.tun_key;
1271	const struct nlattr *nla;
1272	int rem;
1273
1274	flow->key.phy.in_port = DP_MAX_PORTS;
1275	flow->key.phy.priority = 0;
1276	flow->key.phy.skb_mark = 0;
1277	memset(tun_key, 0, sizeof(flow->key.tun_key));
1278
1279	nla_for_each_nested(nla, attr, rem) {
1280		int type = nla_type(nla);
1281
1282		if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1283			int err;
1284
1285			if (nla_len(nla) != ovs_key_lens[type])
1286				return -EINVAL;
1287
1288			switch (type) {
1289			case OVS_KEY_ATTR_PRIORITY:
1290				flow->key.phy.priority = nla_get_u32(nla);
1291				break;
1292
1293			case OVS_KEY_ATTR_TUNNEL:
1294				err = ovs_ipv4_tun_from_nlattr(nla, tun_key);
1295				if (err)
1296					return err;
1297				break;
1298
1299			case OVS_KEY_ATTR_IN_PORT:
1300				if (nla_get_u32(nla) >= DP_MAX_PORTS)
1301					return -EINVAL;
1302				flow->key.phy.in_port = nla_get_u32(nla);
1303				break;
1304
1305			case OVS_KEY_ATTR_SKB_MARK:
1306				flow->key.phy.skb_mark = nla_get_u32(nla);
1307				break;
1308			}
1309		}
1310	}
1311	if (rem)
1312		return -EINVAL;
1313
1314	flow->hash = ovs_flow_hash(&flow->key,
1315				   flow_key_start(&flow->key), key_len);
1316
1317	return 0;
1318}
1319
1320int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1321{
1322	struct ovs_key_ethernet *eth_key;
1323	struct nlattr *nla, *encap;
1324
1325	if (swkey->phy.priority &&
1326	    nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority))
1327		goto nla_put_failure;
1328
1329	if (swkey->tun_key.ipv4_dst &&
1330	    ovs_ipv4_tun_to_nlattr(skb, &swkey->tun_key))
1331		goto nla_put_failure;
1332
1333	if (swkey->phy.in_port != DP_MAX_PORTS &&
1334	    nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port))
1335		goto nla_put_failure;
1336
1337	if (swkey->phy.skb_mark &&
1338	    nla_put_u32(skb, OVS_KEY_ATTR_SKB_MARK, swkey->phy.skb_mark))
1339		goto nla_put_failure;
1340
1341	nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1342	if (!nla)
1343		goto nla_put_failure;
1344	eth_key = nla_data(nla);
1345	memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1346	memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1347
1348	if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1349		if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q)) ||
1350		    nla_put_be16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci))
1351			goto nla_put_failure;
1352		encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1353		if (!swkey->eth.tci)
1354			goto unencap;
1355	} else {
1356		encap = NULL;
1357	}
1358
1359	if (swkey->eth.type == htons(ETH_P_802_2))
1360		goto unencap;
1361
1362	if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type))
1363		goto nla_put_failure;
1364
1365	if (swkey->eth.type == htons(ETH_P_IP)) {
1366		struct ovs_key_ipv4 *ipv4_key;
1367
1368		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1369		if (!nla)
1370			goto nla_put_failure;
1371		ipv4_key = nla_data(nla);
1372		ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1373		ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1374		ipv4_key->ipv4_proto = swkey->ip.proto;
1375		ipv4_key->ipv4_tos = swkey->ip.tos;
1376		ipv4_key->ipv4_ttl = swkey->ip.ttl;
1377		ipv4_key->ipv4_frag = swkey->ip.frag;
1378	} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1379		struct ovs_key_ipv6 *ipv6_key;
1380
1381		nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1382		if (!nla)
1383			goto nla_put_failure;
1384		ipv6_key = nla_data(nla);
1385		memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1386				sizeof(ipv6_key->ipv6_src));
1387		memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1388				sizeof(ipv6_key->ipv6_dst));
1389		ipv6_key->ipv6_label = swkey->ipv6.label;
1390		ipv6_key->ipv6_proto = swkey->ip.proto;
1391		ipv6_key->ipv6_tclass = swkey->ip.tos;
1392		ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1393		ipv6_key->ipv6_frag = swkey->ip.frag;
1394	} else if (swkey->eth.type == htons(ETH_P_ARP) ||
1395		   swkey->eth.type == htons(ETH_P_RARP)) {
1396		struct ovs_key_arp *arp_key;
1397
1398		nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1399		if (!nla)
1400			goto nla_put_failure;
1401		arp_key = nla_data(nla);
1402		memset(arp_key, 0, sizeof(struct ovs_key_arp));
1403		arp_key->arp_sip = swkey->ipv4.addr.src;
1404		arp_key->arp_tip = swkey->ipv4.addr.dst;
1405		arp_key->arp_op = htons(swkey->ip.proto);
1406		memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1407		memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1408	}
1409
1410	if ((swkey->eth.type == htons(ETH_P_IP) ||
1411	     swkey->eth.type == htons(ETH_P_IPV6)) &&
1412	     swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1413
1414		if (swkey->ip.proto == IPPROTO_TCP) {
1415			struct ovs_key_tcp *tcp_key;
1416
1417			nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1418			if (!nla)
1419				goto nla_put_failure;
1420			tcp_key = nla_data(nla);
1421			if (swkey->eth.type == htons(ETH_P_IP)) {
1422				tcp_key->tcp_src = swkey->ipv4.tp.src;
1423				tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1424			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1425				tcp_key->tcp_src = swkey->ipv6.tp.src;
1426				tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1427			}
1428		} else if (swkey->ip.proto == IPPROTO_UDP) {
1429			struct ovs_key_udp *udp_key;
1430
1431			nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1432			if (!nla)
1433				goto nla_put_failure;
1434			udp_key = nla_data(nla);
1435			if (swkey->eth.type == htons(ETH_P_IP)) {
1436				udp_key->udp_src = swkey->ipv4.tp.src;
1437				udp_key->udp_dst = swkey->ipv4.tp.dst;
1438			} else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1439				udp_key->udp_src = swkey->ipv6.tp.src;
1440				udp_key->udp_dst = swkey->ipv6.tp.dst;
1441			}
1442		} else if (swkey->eth.type == htons(ETH_P_IP) &&
1443			   swkey->ip.proto == IPPROTO_ICMP) {
1444			struct ovs_key_icmp *icmp_key;
1445
1446			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1447			if (!nla)
1448				goto nla_put_failure;
1449			icmp_key = nla_data(nla);
1450			icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1451			icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1452		} else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1453			   swkey->ip.proto == IPPROTO_ICMPV6) {
1454			struct ovs_key_icmpv6 *icmpv6_key;
1455
1456			nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1457						sizeof(*icmpv6_key));
1458			if (!nla)
1459				goto nla_put_failure;
1460			icmpv6_key = nla_data(nla);
1461			icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1462			icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1463
1464			if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1465			    icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1466				struct ovs_key_nd *nd_key;
1467
1468				nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1469				if (!nla)
1470					goto nla_put_failure;
1471				nd_key = nla_data(nla);
1472				memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1473							sizeof(nd_key->nd_target));
1474				memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1475				memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1476			}
1477		}
1478	}
1479
1480unencap:
1481	if (encap)
1482		nla_nest_end(skb, encap);
1483
1484	return 0;
1485
1486nla_put_failure:
1487	return -EMSGSIZE;
1488}
1489
1490/* Initializes the flow module.
1491 * Returns zero if successful or a negative error code. */
1492int ovs_flow_init(void)
1493{
1494	flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1495					0, NULL);
1496	if (flow_cache == NULL)
1497		return -ENOMEM;
1498
1499	return 0;
1500}
1501
1502/* Uninitializes the flow module. */
1503void ovs_flow_exit(void)
1504{
1505	kmem_cache_destroy(flow_cache);
1506}
1507