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v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2007-2014 Nicira, Inc.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  4 */
  5
 
 
  6#include <linux/uaccess.h>
  7#include <linux/netdevice.h>
  8#include <linux/etherdevice.h>
  9#include <linux/if_ether.h>
 10#include <linux/if_vlan.h>
 11#include <net/llc_pdu.h>
 12#include <linux/kernel.h>
 13#include <linux/jhash.h>
 14#include <linux/jiffies.h>
 15#include <linux/llc.h>
 16#include <linux/module.h>
 17#include <linux/in.h>
 18#include <linux/rcupdate.h>
 19#include <linux/cpumask.h>
 20#include <linux/if_arp.h>
 21#include <linux/ip.h>
 22#include <linux/ipv6.h>
 23#include <linux/mpls.h>
 24#include <linux/sctp.h>
 25#include <linux/smp.h>
 26#include <linux/tcp.h>
 27#include <linux/udp.h>
 28#include <linux/icmp.h>
 29#include <linux/icmpv6.h>
 30#include <linux/rculist.h>
 31#include <net/ip.h>
 32#include <net/ip_tunnels.h>
 33#include <net/ipv6.h>
 34#include <net/mpls.h>
 35#include <net/ndisc.h>
 36#include <net/nsh.h>
 37
 38#include "conntrack.h"
 39#include "datapath.h"
 40#include "flow.h"
 41#include "flow_netlink.h"
 42#include "vport.h"
 43
 44u64 ovs_flow_used_time(unsigned long flow_jiffies)
 45{
 46	struct timespec64 cur_ts;
 47	u64 cur_ms, idle_ms;
 48
 49	ktime_get_ts64(&cur_ts);
 50	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 51	cur_ms = (u64)(u32)cur_ts.tv_sec * MSEC_PER_SEC +
 52		 cur_ts.tv_nsec / NSEC_PER_MSEC;
 53
 54	return cur_ms - idle_ms;
 55}
 56
 57#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
 58
 59void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
 60			   const struct sk_buff *skb)
 61{
 62	struct sw_flow_stats *stats;
 63	unsigned int cpu = smp_processor_id();
 64	int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
 65
 66	stats = rcu_dereference(flow->stats[cpu]);
 67
 68	/* Check if already have CPU-specific stats. */
 69	if (likely(stats)) {
 70		spin_lock(&stats->lock);
 71		/* Mark if we write on the pre-allocated stats. */
 72		if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
 73			flow->stats_last_writer = cpu;
 74	} else {
 75		stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
 76		spin_lock(&stats->lock);
 77
 78		/* If the current CPU is the only writer on the
 79		 * pre-allocated stats keep using them.
 80		 */
 81		if (unlikely(flow->stats_last_writer != cpu)) {
 82			/* A previous locker may have already allocated the
 83			 * stats, so we need to check again.  If CPU-specific
 84			 * stats were already allocated, we update the pre-
 85			 * allocated stats as we have already locked them.
 86			 */
 87			if (likely(flow->stats_last_writer != -1) &&
 88			    likely(!rcu_access_pointer(flow->stats[cpu]))) {
 89				/* Try to allocate CPU-specific stats. */
 90				struct sw_flow_stats *new_stats;
 91
 92				new_stats =
 93					kmem_cache_alloc_node(flow_stats_cache,
 94							      GFP_NOWAIT |
 95							      __GFP_THISNODE |
 96							      __GFP_NOWARN |
 97							      __GFP_NOMEMALLOC,
 98							      numa_node_id());
 99				if (likely(new_stats)) {
100					new_stats->used = jiffies;
101					new_stats->packet_count = 1;
102					new_stats->byte_count = len;
103					new_stats->tcp_flags = tcp_flags;
104					spin_lock_init(&new_stats->lock);
105
106					rcu_assign_pointer(flow->stats[cpu],
107							   new_stats);
108					cpumask_set_cpu(cpu, &flow->cpu_used_mask);
109					goto unlock;
110				}
111			}
112			flow->stats_last_writer = cpu;
113		}
114	}
115
 
116	stats->used = jiffies;
117	stats->packet_count++;
118	stats->byte_count += len;
119	stats->tcp_flags |= tcp_flags;
120unlock:
121	spin_unlock(&stats->lock);
122}
123
124/* Must be called with rcu_read_lock or ovs_mutex. */
125void ovs_flow_stats_get(const struct sw_flow *flow,
126			struct ovs_flow_stats *ovs_stats,
 
 
 
 
 
 
 
 
 
 
 
127			unsigned long *used, __be16 *tcp_flags)
128{
129	int cpu;
130
131	*used = 0;
132	*tcp_flags = 0;
133	memset(ovs_stats, 0, sizeof(*ovs_stats));
134
135	/* We open code this to make sure cpu 0 is always considered */
136	for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
137		struct sw_flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
138
139		if (stats) {
140			/* Local CPU may write on non-local stats, so we must
141			 * block bottom-halves here.
142			 */
143			spin_lock_bh(&stats->lock);
144			if (!*used || time_after(stats->used, *used))
145				*used = stats->used;
146			*tcp_flags |= stats->tcp_flags;
147			ovs_stats->n_packets += stats->packet_count;
148			ovs_stats->n_bytes += stats->byte_count;
149			spin_unlock_bh(&stats->lock);
150		}
151	}
 
 
 
 
 
 
 
 
 
 
 
152}
153
154/* Called with ovs_mutex. */
155void ovs_flow_stats_clear(struct sw_flow *flow)
156{
157	int cpu;
158
159	/* We open code this to make sure cpu 0 is always considered */
160	for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
161		struct sw_flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
162
163		if (stats) {
164			spin_lock_bh(&stats->lock);
165			stats->used = 0;
166			stats->packet_count = 0;
167			stats->byte_count = 0;
168			stats->tcp_flags = 0;
169			spin_unlock_bh(&stats->lock);
170		}
171	}
 
172}
173
174static int check_header(struct sk_buff *skb, int len)
175{
176	if (unlikely(skb->len < len))
177		return -EINVAL;
178	if (unlikely(!pskb_may_pull(skb, len)))
179		return -ENOMEM;
180	return 0;
181}
182
183static bool arphdr_ok(struct sk_buff *skb)
184{
185	return pskb_may_pull(skb, skb_network_offset(skb) +
186				  sizeof(struct arp_eth_header));
187}
188
189static int check_iphdr(struct sk_buff *skb)
190{
191	unsigned int nh_ofs = skb_network_offset(skb);
192	unsigned int ip_len;
193	int err;
194
195	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
196	if (unlikely(err))
197		return err;
198
199	ip_len = ip_hdrlen(skb);
200	if (unlikely(ip_len < sizeof(struct iphdr) ||
201		     skb->len < nh_ofs + ip_len))
202		return -EINVAL;
203
204	skb_set_transport_header(skb, nh_ofs + ip_len);
205	return 0;
206}
207
208static bool tcphdr_ok(struct sk_buff *skb)
209{
210	int th_ofs = skb_transport_offset(skb);
211	int tcp_len;
212
213	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
214		return false;
215
216	tcp_len = tcp_hdrlen(skb);
217	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
218		     skb->len < th_ofs + tcp_len))
219		return false;
220
221	return true;
222}
223
224static bool udphdr_ok(struct sk_buff *skb)
225{
226	return pskb_may_pull(skb, skb_transport_offset(skb) +
227				  sizeof(struct udphdr));
228}
229
230static bool sctphdr_ok(struct sk_buff *skb)
231{
232	return pskb_may_pull(skb, skb_transport_offset(skb) +
233				  sizeof(struct sctphdr));
234}
235
236static bool icmphdr_ok(struct sk_buff *skb)
237{
238	return pskb_may_pull(skb, skb_transport_offset(skb) +
239				  sizeof(struct icmphdr));
240}
241
242static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
243{
244	unsigned short frag_off;
245	unsigned int payload_ofs = 0;
246	unsigned int nh_ofs = skb_network_offset(skb);
247	unsigned int nh_len;
 
248	struct ipv6hdr *nh;
249	int err, nexthdr, flags = 0;
 
 
250
251	err = check_header(skb, nh_ofs + sizeof(*nh));
252	if (unlikely(err))
253		return err;
254
255	nh = ipv6_hdr(skb);
 
 
256
257	key->ip.proto = NEXTHDR_NONE;
258	key->ip.tos = ipv6_get_dsfield(nh);
259	key->ip.ttl = nh->hop_limit;
260	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
261	key->ipv6.addr.src = nh->saddr;
262	key->ipv6.addr.dst = nh->daddr;
263
264	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
265	if (flags & IP6_FH_F_FRAG) {
266		if (frag_off) {
 
 
 
267			key->ip.frag = OVS_FRAG_TYPE_LATER;
268			key->ip.proto = nexthdr;
269			return 0;
270		}
271		key->ip.frag = OVS_FRAG_TYPE_FIRST;
272	} else {
273		key->ip.frag = OVS_FRAG_TYPE_NONE;
274	}
275
276	/* Delayed handling of error in ipv6_find_hdr() as it
277	 * always sets flags and frag_off to a valid value which may be
278	 * used to set key->ip.frag above.
279	 */
280	if (unlikely(nexthdr < 0))
281		return -EPROTO;
282
283	nh_len = payload_ofs - nh_ofs;
284	skb_set_transport_header(skb, nh_ofs + nh_len);
285	key->ip.proto = nexthdr;
286	return nh_len;
287}
288
289static bool icmp6hdr_ok(struct sk_buff *skb)
290{
291	return pskb_may_pull(skb, skb_transport_offset(skb) +
292				  sizeof(struct icmp6hdr));
293}
294
295/**
296 * Parse vlan tag from vlan header.
297 * Returns ERROR on memory error.
298 * Returns 0 if it encounters a non-vlan or incomplete packet.
299 * Returns 1 after successfully parsing vlan tag.
300 */
301static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
302			  bool untag_vlan)
303{
304	struct vlan_head *vh = (struct vlan_head *)skb->data;
305
306	if (likely(!eth_type_vlan(vh->tpid)))
307		return 0;
 
308
309	if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
310		return 0;
311
312	if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
313				 sizeof(__be16))))
314		return -ENOMEM;
315
316	vh = (struct vlan_head *)skb->data;
317	key_vh->tci = vh->tci | htons(VLAN_CFI_MASK);
318	key_vh->tpid = vh->tpid;
319
320	if (unlikely(untag_vlan)) {
321		int offset = skb->data - skb_mac_header(skb);
322		u16 tci;
323		int err;
324
325		__skb_push(skb, offset);
326		err = __skb_vlan_pop(skb, &tci);
327		__skb_pull(skb, offset);
328		if (err)
329			return err;
330		__vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
331	} else {
332		__skb_pull(skb, sizeof(struct vlan_head));
333	}
334	return 1;
335}
336
337static void clear_vlan(struct sw_flow_key *key)
338{
339	key->eth.vlan.tci = 0;
340	key->eth.vlan.tpid = 0;
341	key->eth.cvlan.tci = 0;
342	key->eth.cvlan.tpid = 0;
343}
344
345static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
346{
347	int res;
348
349	if (skb_vlan_tag_present(skb)) {
350		key->eth.vlan.tci = htons(skb->vlan_tci) | htons(VLAN_CFI_MASK);
351		key->eth.vlan.tpid = skb->vlan_proto;
352	} else {
353		/* Parse outer vlan tag in the non-accelerated case. */
354		res = parse_vlan_tag(skb, &key->eth.vlan, true);
355		if (res <= 0)
356			return res;
357	}
358
359	/* Parse inner vlan tag. */
360	res = parse_vlan_tag(skb, &key->eth.cvlan, false);
361	if (res <= 0)
362		return res;
363
364	return 0;
365}
366
367static __be16 parse_ethertype(struct sk_buff *skb)
368{
369	struct llc_snap_hdr {
370		u8  dsap;  /* Always 0xAA */
371		u8  ssap;  /* Always 0xAA */
372		u8  ctrl;
373		u8  oui[3];
374		__be16 ethertype;
375	};
376	struct llc_snap_hdr *llc;
377	__be16 proto;
378
379	proto = *(__be16 *) skb->data;
380	__skb_pull(skb, sizeof(__be16));
381
382	if (eth_proto_is_802_3(proto))
383		return proto;
384
385	if (skb->len < sizeof(struct llc_snap_hdr))
386		return htons(ETH_P_802_2);
387
388	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
389		return htons(0);
390
391	llc = (struct llc_snap_hdr *) skb->data;
392	if (llc->dsap != LLC_SAP_SNAP ||
393	    llc->ssap != LLC_SAP_SNAP ||
394	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
395		return htons(ETH_P_802_2);
396
397	__skb_pull(skb, sizeof(struct llc_snap_hdr));
398
399	if (eth_proto_is_802_3(llc->ethertype))
400		return llc->ethertype;
401
402	return htons(ETH_P_802_2);
403}
404
405static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
406			int nh_len)
407{
408	struct icmp6hdr *icmp = icmp6_hdr(skb);
409
410	/* The ICMPv6 type and code fields use the 16-bit transport port
411	 * fields, so we need to store them in 16-bit network byte order.
412	 */
413	key->tp.src = htons(icmp->icmp6_type);
414	key->tp.dst = htons(icmp->icmp6_code);
415	memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
416
417	if (icmp->icmp6_code == 0 &&
418	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
419	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
420		int icmp_len = skb->len - skb_transport_offset(skb);
421		struct nd_msg *nd;
422		int offset;
423
424		/* In order to process neighbor discovery options, we need the
425		 * entire packet.
426		 */
427		if (unlikely(icmp_len < sizeof(*nd)))
428			return 0;
429
430		if (unlikely(skb_linearize(skb)))
431			return -ENOMEM;
432
433		nd = (struct nd_msg *)skb_transport_header(skb);
434		key->ipv6.nd.target = nd->target;
435
436		icmp_len -= sizeof(*nd);
437		offset = 0;
438		while (icmp_len >= 8) {
439			struct nd_opt_hdr *nd_opt =
440				 (struct nd_opt_hdr *)(nd->opt + offset);
441			int opt_len = nd_opt->nd_opt_len * 8;
442
443			if (unlikely(!opt_len || opt_len > icmp_len))
444				return 0;
445
446			/* Store the link layer address if the appropriate
447			 * option is provided.  It is considered an error if
448			 * the same link layer option is specified twice.
449			 */
450			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
451			    && opt_len == 8) {
452				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
453					goto invalid;
454				ether_addr_copy(key->ipv6.nd.sll,
455						&nd->opt[offset+sizeof(*nd_opt)]);
456			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
457				   && opt_len == 8) {
458				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
459					goto invalid;
460				ether_addr_copy(key->ipv6.nd.tll,
461						&nd->opt[offset+sizeof(*nd_opt)]);
462			}
463
464			icmp_len -= opt_len;
465			offset += opt_len;
466		}
467	}
468
469	return 0;
470
471invalid:
472	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
473	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
474	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
475
476	return 0;
477}
478
479static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
480{
481	struct nshhdr *nh;
482	unsigned int nh_ofs = skb_network_offset(skb);
483	u8 version, length;
484	int err;
485
486	err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN);
487	if (unlikely(err))
488		return err;
489
490	nh = nsh_hdr(skb);
491	version = nsh_get_ver(nh);
492	length = nsh_hdr_len(nh);
 
 
493
494	if (version != 0)
495		return -EINVAL;
496
497	err = check_header(skb, nh_ofs + length);
498	if (unlikely(err))
499		return err;
 
 
 
 
 
 
 
 
500
501	nh = nsh_hdr(skb);
502	key->nsh.base.flags = nsh_get_flags(nh);
503	key->nsh.base.ttl = nsh_get_ttl(nh);
504	key->nsh.base.mdtype = nh->mdtype;
505	key->nsh.base.np = nh->np;
506	key->nsh.base.path_hdr = nh->path_hdr;
507	switch (key->nsh.base.mdtype) {
508	case NSH_M_TYPE1:
509		if (length != NSH_M_TYPE1_LEN)
510			return -EINVAL;
511		memcpy(key->nsh.context, nh->md1.context,
512		       sizeof(nh->md1));
513		break;
514	case NSH_M_TYPE2:
515		memset(key->nsh.context, 0,
516		       sizeof(nh->md1));
517		break;
518	default:
519		return -EINVAL;
520	}
521
522	return 0;
523}
 
524
525/**
526 * key_extract_l3l4 - extracts L3/L4 header information.
527 * @skb: sk_buff that contains the frame, with skb->data pointing to the
528 *       L3 header
529 * @key: output flow key
530 *
531 */
532static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
533{
534	int error;
535
536	/* Network layer. */
537	if (key->eth.type == htons(ETH_P_IP)) {
538		struct iphdr *nh;
539		__be16 offset;
540
541		error = check_iphdr(skb);
542		if (unlikely(error)) {
543			memset(&key->ip, 0, sizeof(key->ip));
544			memset(&key->ipv4, 0, sizeof(key->ipv4));
545			if (error == -EINVAL) {
546				skb->transport_header = skb->network_header;
547				error = 0;
548			}
549			return error;
550		}
551
552		nh = ip_hdr(skb);
553		key->ipv4.addr.src = nh->saddr;
554		key->ipv4.addr.dst = nh->daddr;
555
556		key->ip.proto = nh->protocol;
557		key->ip.tos = nh->tos;
558		key->ip.ttl = nh->ttl;
559
560		offset = nh->frag_off & htons(IP_OFFSET);
561		if (offset) {
562			key->ip.frag = OVS_FRAG_TYPE_LATER;
563			memset(&key->tp, 0, sizeof(key->tp));
564			return 0;
565		}
566		if (nh->frag_off & htons(IP_MF) ||
567			skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
568			key->ip.frag = OVS_FRAG_TYPE_FIRST;
569		else
570			key->ip.frag = OVS_FRAG_TYPE_NONE;
571
572		/* Transport layer. */
573		if (key->ip.proto == IPPROTO_TCP) {
574			if (tcphdr_ok(skb)) {
575				struct tcphdr *tcp = tcp_hdr(skb);
576				key->tp.src = tcp->source;
577				key->tp.dst = tcp->dest;
578				key->tp.flags = TCP_FLAGS_BE16(tcp);
579			} else {
580				memset(&key->tp, 0, sizeof(key->tp));
581			}
582
583		} else if (key->ip.proto == IPPROTO_UDP) {
584			if (udphdr_ok(skb)) {
585				struct udphdr *udp = udp_hdr(skb);
586				key->tp.src = udp->source;
587				key->tp.dst = udp->dest;
588			} else {
589				memset(&key->tp, 0, sizeof(key->tp));
590			}
591		} else if (key->ip.proto == IPPROTO_SCTP) {
592			if (sctphdr_ok(skb)) {
593				struct sctphdr *sctp = sctp_hdr(skb);
594				key->tp.src = sctp->source;
595				key->tp.dst = sctp->dest;
596			} else {
597				memset(&key->tp, 0, sizeof(key->tp));
598			}
599		} else if (key->ip.proto == IPPROTO_ICMP) {
600			if (icmphdr_ok(skb)) {
601				struct icmphdr *icmp = icmp_hdr(skb);
602				/* The ICMP type and code fields use the 16-bit
603				 * transport port fields, so we need to store
604				 * them in 16-bit network byte order. */
605				key->tp.src = htons(icmp->type);
606				key->tp.dst = htons(icmp->code);
607			} else {
608				memset(&key->tp, 0, sizeof(key->tp));
609			}
610		}
611
612	} else if (key->eth.type == htons(ETH_P_ARP) ||
613		   key->eth.type == htons(ETH_P_RARP)) {
614		struct arp_eth_header *arp;
615		bool arp_available = arphdr_ok(skb);
616
617		arp = (struct arp_eth_header *)skb_network_header(skb);
618
619		if (arp_available &&
620		    arp->ar_hrd == htons(ARPHRD_ETHER) &&
621		    arp->ar_pro == htons(ETH_P_IP) &&
622		    arp->ar_hln == ETH_ALEN &&
623		    arp->ar_pln == 4) {
624
625			/* We only match on the lower 8 bits of the opcode. */
626			if (ntohs(arp->ar_op) <= 0xff)
627				key->ip.proto = ntohs(arp->ar_op);
628			else
629				key->ip.proto = 0;
630
631			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
632			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
633			ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
634			ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
635		} else {
636			memset(&key->ip, 0, sizeof(key->ip));
637			memset(&key->ipv4, 0, sizeof(key->ipv4));
638		}
639	} else if (eth_p_mpls(key->eth.type)) {
640		size_t stack_len = MPLS_HLEN;
641
642		skb_set_inner_network_header(skb, skb->mac_len);
643		while (1) {
644			__be32 lse;
645
646			error = check_header(skb, skb->mac_len + stack_len);
647			if (unlikely(error))
648				return 0;
649
650			memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
651
652			if (stack_len == MPLS_HLEN)
653				memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
654
655			skb_set_inner_network_header(skb, skb->mac_len + stack_len);
656			if (lse & htonl(MPLS_LS_S_MASK))
657				break;
658
659			stack_len += MPLS_HLEN;
660		}
661	} else if (key->eth.type == htons(ETH_P_IPV6)) {
662		int nh_len;             /* IPv6 Header + Extensions */
663
664		nh_len = parse_ipv6hdr(skb, key);
665		if (unlikely(nh_len < 0)) {
666			switch (nh_len) {
667			case -EINVAL:
668				memset(&key->ip, 0, sizeof(key->ip));
669				memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
670				/* fall-through */
671			case -EPROTO:
672				skb->transport_header = skb->network_header;
673				error = 0;
674				break;
675			default:
676				error = nh_len;
677			}
678			return error;
679		}
680
681		if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
682			memset(&key->tp, 0, sizeof(key->tp));
683			return 0;
684		}
685		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
686			key->ip.frag = OVS_FRAG_TYPE_FIRST;
687
688		/* Transport layer. */
689		if (key->ip.proto == NEXTHDR_TCP) {
690			if (tcphdr_ok(skb)) {
691				struct tcphdr *tcp = tcp_hdr(skb);
692				key->tp.src = tcp->source;
693				key->tp.dst = tcp->dest;
694				key->tp.flags = TCP_FLAGS_BE16(tcp);
695			} else {
696				memset(&key->tp, 0, sizeof(key->tp));
697			}
698		} else if (key->ip.proto == NEXTHDR_UDP) {
699			if (udphdr_ok(skb)) {
700				struct udphdr *udp = udp_hdr(skb);
701				key->tp.src = udp->source;
702				key->tp.dst = udp->dest;
703			} else {
704				memset(&key->tp, 0, sizeof(key->tp));
705			}
706		} else if (key->ip.proto == NEXTHDR_SCTP) {
707			if (sctphdr_ok(skb)) {
708				struct sctphdr *sctp = sctp_hdr(skb);
709				key->tp.src = sctp->source;
710				key->tp.dst = sctp->dest;
711			} else {
712				memset(&key->tp, 0, sizeof(key->tp));
713			}
714		} else if (key->ip.proto == NEXTHDR_ICMP) {
715			if (icmp6hdr_ok(skb)) {
716				error = parse_icmpv6(skb, key, nh_len);
717				if (error)
718					return error;
719			} else {
720				memset(&key->tp, 0, sizeof(key->tp));
721			}
722		}
723	} else if (key->eth.type == htons(ETH_P_NSH)) {
724		error = parse_nsh(skb, key);
725		if (error)
726			return error;
727	}
728	return 0;
729}
730
731/**
732 * key_extract - extracts a flow key from an Ethernet frame.
733 * @skb: sk_buff that contains the frame, with skb->data pointing to the
734 * Ethernet header
735 * @key: output flow key
736 *
737 * The caller must ensure that skb->len >= ETH_HLEN.
738 *
739 * Returns 0 if successful, otherwise a negative errno value.
740 *
741 * Initializes @skb header fields as follows:
742 *
743 *    - skb->mac_header: the L2 header.
744 *
745 *    - skb->network_header: just past the L2 header, or just past the
746 *      VLAN header, to the first byte of the L2 payload.
747 *
748 *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
749 *      on output, then just past the IP header, if one is present and
750 *      of a correct length, otherwise the same as skb->network_header.
751 *      For other key->eth.type values it is left untouched.
752 *
753 *    - skb->protocol: the type of the data starting at skb->network_header.
754 *      Equals to key->eth.type.
755 */
756static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
757{
758	struct ethhdr *eth;
759
760	/* Flags are always used as part of stats */
761	key->tp.flags = 0;
762
763	skb_reset_mac_header(skb);
764
765	/* Link layer. */
766	clear_vlan(key);
767	if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
768		if (unlikely(eth_type_vlan(skb->protocol)))
769			return -EINVAL;
770
771		skb_reset_network_header(skb);
772		key->eth.type = skb->protocol;
773	} else {
774		eth = eth_hdr(skb);
775		ether_addr_copy(key->eth.src, eth->h_source);
776		ether_addr_copy(key->eth.dst, eth->h_dest);
777
778		__skb_pull(skb, 2 * ETH_ALEN);
779		/* We are going to push all headers that we pull, so no need to
780		 * update skb->csum here.
781		 */
782
783		if (unlikely(parse_vlan(skb, key)))
784			return -ENOMEM;
785
786		key->eth.type = parse_ethertype(skb);
787		if (unlikely(key->eth.type == htons(0)))
788			return -ENOMEM;
789
790		/* Multiple tagged packets need to retain TPID to satisfy
791		 * skb_vlan_pop(), which will later shift the ethertype into
792		 * skb->protocol.
793		 */
794		if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
795			skb->protocol = key->eth.cvlan.tpid;
796		else
797			skb->protocol = key->eth.type;
798
799		skb_reset_network_header(skb);
800		__skb_push(skb, skb->data - skb_mac_header(skb));
801	}
802
803	skb_reset_mac_len(skb);
804
805	/* Fill out L3/L4 key info, if any */
806	return key_extract_l3l4(skb, key);
807}
808
809/* In the case of conntrack fragment handling it expects L3 headers,
810 * add a helper.
811 */
812int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
813{
814	return key_extract_l3l4(skb, key);
815}
816
817int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
818{
819	int res;
820
821	res = key_extract(skb, key);
822	if (!res)
823		key->mac_proto &= ~SW_FLOW_KEY_INVALID;
824
825	return res;
826}
827
828static int key_extract_mac_proto(struct sk_buff *skb)
829{
830	switch (skb->dev->type) {
831	case ARPHRD_ETHER:
832		return MAC_PROTO_ETHERNET;
833	case ARPHRD_NONE:
834		if (skb->protocol == htons(ETH_P_TEB))
835			return MAC_PROTO_ETHERNET;
836		return MAC_PROTO_NONE;
837	}
838	WARN_ON_ONCE(1);
839	return -EINVAL;
840}
841
842int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
843			 struct sk_buff *skb, struct sw_flow_key *key)
844{
845#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
846	struct tc_skb_ext *tc_ext;
847#endif
848	int res, err;
849
850	/* Extract metadata from packet. */
851	if (tun_info) {
852		key->tun_proto = ip_tunnel_info_af(tun_info);
853		memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
854
855		if (tun_info->options_len) {
856			BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
857						   8)) - 1
858					> sizeof(key->tun_opts));
859
860			ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
861						tun_info);
862			key->tun_opts_len = tun_info->options_len;
863		} else {
864			key->tun_opts_len = 0;
865		}
866	} else  {
867		key->tun_proto = 0;
868		key->tun_opts_len = 0;
869		memset(&key->tun_key, 0, sizeof(key->tun_key));
870	}
871
872	key->phy.priority = skb->priority;
873	key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
874	key->phy.skb_mark = skb->mark;
875	key->ovs_flow_hash = 0;
876	res = key_extract_mac_proto(skb);
877	if (res < 0)
878		return res;
879	key->mac_proto = res;
880
881#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
882	if (static_branch_unlikely(&tc_recirc_sharing_support)) {
883		tc_ext = skb_ext_find(skb, TC_SKB_EXT);
884		key->recirc_id = tc_ext ? tc_ext->chain : 0;
885	} else {
886		key->recirc_id = 0;
887	}
888#else
889	key->recirc_id = 0;
890#endif
891
892	err = key_extract(skb, key);
893	if (!err)
894		ovs_ct_fill_key(skb, key);   /* Must be after key_extract(). */
895	return err;
896}
897
898int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
899				   struct sk_buff *skb,
900				   struct sw_flow_key *key, bool log)
901{
902	const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
903	u64 attrs = 0;
904	int err;
905
906	err = parse_flow_nlattrs(attr, a, &attrs, log);
907	if (err)
908		return -EINVAL;
909
910	/* Extract metadata from netlink attributes. */
911	err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
912	if (err)
913		return err;
914
915	/* key_extract assumes that skb->protocol is set-up for
916	 * layer 3 packets which is the case for other callers,
917	 * in particular packets received from the network stack.
918	 * Here the correct value can be set from the metadata
919	 * extracted above.
920	 * For L2 packet key eth type would be zero. skb protocol
921	 * would be set to correct value later during key-extact.
922	 */
923
924	skb->protocol = key->eth.type;
925	err = key_extract(skb, key);
926	if (err)
927		return err;
928
929	/* Check that we have conntrack original direction tuple metadata only
930	 * for packets for which it makes sense.  Otherwise the key may be
931	 * corrupted due to overlapping key fields.
932	 */
933	if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
934	    key->eth.type != htons(ETH_P_IP))
935		return -EINVAL;
936	if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
937	    (key->eth.type != htons(ETH_P_IPV6) ||
938	     sw_flow_key_is_nd(key)))
939		return -EINVAL;
940
941	return 0;
942}
v3.15
 
  1/*
  2 * Copyright (c) 2007-2013 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/sctp.h>
 38#include <linux/smp.h>
 39#include <linux/tcp.h>
 40#include <linux/udp.h>
 41#include <linux/icmp.h>
 42#include <linux/icmpv6.h>
 43#include <linux/rculist.h>
 44#include <net/ip.h>
 45#include <net/ip_tunnels.h>
 46#include <net/ipv6.h>
 
 47#include <net/ndisc.h>
 
 
 
 
 
 
 
 48
 49u64 ovs_flow_used_time(unsigned long flow_jiffies)
 50{
 51	struct timespec cur_ts;
 52	u64 cur_ms, idle_ms;
 53
 54	ktime_get_ts(&cur_ts);
 55	idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 56	cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 57		 cur_ts.tv_nsec / NSEC_PER_MSEC;
 58
 59	return cur_ms - idle_ms;
 60}
 61
 62#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
 63
 64void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb)
 
 65{
 66	struct flow_stats *stats;
 67	__be16 tcp_flags = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 68
 69	if (!flow->stats.is_percpu)
 70		stats = flow->stats.stat;
 71	else
 72		stats = this_cpu_ptr(flow->stats.cpu_stats);
 73
 74	if ((flow->key.eth.type == htons(ETH_P_IP) ||
 75	     flow->key.eth.type == htons(ETH_P_IPV6)) &&
 76	    flow->key.ip.frag != OVS_FRAG_TYPE_LATER &&
 77	    flow->key.ip.proto == IPPROTO_TCP &&
 78	    likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
 79		tcp_flags = TCP_FLAGS_BE16(tcp_hdr(skb));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80	}
 81
 82	spin_lock(&stats->lock);
 83	stats->used = jiffies;
 84	stats->packet_count++;
 85	stats->byte_count += skb->len;
 86	stats->tcp_flags |= tcp_flags;
 
 87	spin_unlock(&stats->lock);
 88}
 89
 90static void stats_read(struct flow_stats *stats,
 91		       struct ovs_flow_stats *ovs_stats,
 92		       unsigned long *used, __be16 *tcp_flags)
 93{
 94	spin_lock(&stats->lock);
 95	if (!*used || time_after(stats->used, *used))
 96		*used = stats->used;
 97	*tcp_flags |= stats->tcp_flags;
 98	ovs_stats->n_packets += stats->packet_count;
 99	ovs_stats->n_bytes += stats->byte_count;
100	spin_unlock(&stats->lock);
101}
102
103void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats,
104			unsigned long *used, __be16 *tcp_flags)
105{
106	int cpu;
107
108	*used = 0;
109	*tcp_flags = 0;
110	memset(ovs_stats, 0, sizeof(*ovs_stats));
111
112	local_bh_disable();
113	if (!flow->stats.is_percpu) {
114		stats_read(flow->stats.stat, ovs_stats, used, tcp_flags);
115	} else {
116		for_each_possible_cpu(cpu) {
117			struct flow_stats *stats;
118
119			stats = per_cpu_ptr(flow->stats.cpu_stats, cpu);
120			stats_read(stats, ovs_stats, used, tcp_flags);
 
 
 
 
 
 
121		}
122	}
123	local_bh_enable();
124}
125
126static void stats_reset(struct flow_stats *stats)
127{
128	spin_lock(&stats->lock);
129	stats->used = 0;
130	stats->packet_count = 0;
131	stats->byte_count = 0;
132	stats->tcp_flags = 0;
133	spin_unlock(&stats->lock);
134}
135
 
136void ovs_flow_stats_clear(struct sw_flow *flow)
137{
138	int cpu;
139
140	local_bh_disable();
141	if (!flow->stats.is_percpu) {
142		stats_reset(flow->stats.stat);
143	} else {
144		for_each_possible_cpu(cpu) {
145			stats_reset(per_cpu_ptr(flow->stats.cpu_stats, cpu));
 
 
 
 
 
146		}
147	}
148	local_bh_enable();
149}
150
151static int check_header(struct sk_buff *skb, int len)
152{
153	if (unlikely(skb->len < len))
154		return -EINVAL;
155	if (unlikely(!pskb_may_pull(skb, len)))
156		return -ENOMEM;
157	return 0;
158}
159
160static bool arphdr_ok(struct sk_buff *skb)
161{
162	return pskb_may_pull(skb, skb_network_offset(skb) +
163				  sizeof(struct arp_eth_header));
164}
165
166static int check_iphdr(struct sk_buff *skb)
167{
168	unsigned int nh_ofs = skb_network_offset(skb);
169	unsigned int ip_len;
170	int err;
171
172	err = check_header(skb, nh_ofs + sizeof(struct iphdr));
173	if (unlikely(err))
174		return err;
175
176	ip_len = ip_hdrlen(skb);
177	if (unlikely(ip_len < sizeof(struct iphdr) ||
178		     skb->len < nh_ofs + ip_len))
179		return -EINVAL;
180
181	skb_set_transport_header(skb, nh_ofs + ip_len);
182	return 0;
183}
184
185static bool tcphdr_ok(struct sk_buff *skb)
186{
187	int th_ofs = skb_transport_offset(skb);
188	int tcp_len;
189
190	if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
191		return false;
192
193	tcp_len = tcp_hdrlen(skb);
194	if (unlikely(tcp_len < sizeof(struct tcphdr) ||
195		     skb->len < th_ofs + tcp_len))
196		return false;
197
198	return true;
199}
200
201static bool udphdr_ok(struct sk_buff *skb)
202{
203	return pskb_may_pull(skb, skb_transport_offset(skb) +
204				  sizeof(struct udphdr));
205}
206
207static bool sctphdr_ok(struct sk_buff *skb)
208{
209	return pskb_may_pull(skb, skb_transport_offset(skb) +
210				  sizeof(struct sctphdr));
211}
212
213static bool icmphdr_ok(struct sk_buff *skb)
214{
215	return pskb_may_pull(skb, skb_transport_offset(skb) +
216				  sizeof(struct icmphdr));
217}
218
219static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
220{
 
 
221	unsigned int nh_ofs = skb_network_offset(skb);
222	unsigned int nh_len;
223	int payload_ofs;
224	struct ipv6hdr *nh;
225	uint8_t nexthdr;
226	__be16 frag_off;
227	int err;
228
229	err = check_header(skb, nh_ofs + sizeof(*nh));
230	if (unlikely(err))
231		return err;
232
233	nh = ipv6_hdr(skb);
234	nexthdr = nh->nexthdr;
235	payload_ofs = (u8 *)(nh + 1) - skb->data;
236
237	key->ip.proto = NEXTHDR_NONE;
238	key->ip.tos = ipv6_get_dsfield(nh);
239	key->ip.ttl = nh->hop_limit;
240	key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
241	key->ipv6.addr.src = nh->saddr;
242	key->ipv6.addr.dst = nh->daddr;
243
244	payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
245	if (unlikely(payload_ofs < 0))
246		return -EINVAL;
247
248	if (frag_off) {
249		if (frag_off & htons(~0x7))
250			key->ip.frag = OVS_FRAG_TYPE_LATER;
251		else
252			key->ip.frag = OVS_FRAG_TYPE_FIRST;
 
 
 
 
253	}
254
 
 
 
 
 
 
 
255	nh_len = payload_ofs - nh_ofs;
256	skb_set_transport_header(skb, nh_ofs + nh_len);
257	key->ip.proto = nexthdr;
258	return nh_len;
259}
260
261static bool icmp6hdr_ok(struct sk_buff *skb)
262{
263	return pskb_may_pull(skb, skb_transport_offset(skb) +
264				  sizeof(struct icmp6hdr));
265}
266
267static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 
 
 
 
 
 
 
268{
269	struct qtag_prefix {
270		__be16 eth_type; /* ETH_P_8021Q */
271		__be16 tci;
272	};
273	struct qtag_prefix *qp;
274
275	if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
276		return 0;
277
278	if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
279					 sizeof(__be16))))
280		return -ENOMEM;
281
282	qp = (struct qtag_prefix *) skb->data;
283	key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
284	__skb_pull(skb, sizeof(struct qtag_prefix));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
285
286	return 0;
287}
288
289static __be16 parse_ethertype(struct sk_buff *skb)
290{
291	struct llc_snap_hdr {
292		u8  dsap;  /* Always 0xAA */
293		u8  ssap;  /* Always 0xAA */
294		u8  ctrl;
295		u8  oui[3];
296		__be16 ethertype;
297	};
298	struct llc_snap_hdr *llc;
299	__be16 proto;
300
301	proto = *(__be16 *) skb->data;
302	__skb_pull(skb, sizeof(__be16));
303
304	if (ntohs(proto) >= ETH_P_802_3_MIN)
305		return proto;
306
307	if (skb->len < sizeof(struct llc_snap_hdr))
308		return htons(ETH_P_802_2);
309
310	if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
311		return htons(0);
312
313	llc = (struct llc_snap_hdr *) skb->data;
314	if (llc->dsap != LLC_SAP_SNAP ||
315	    llc->ssap != LLC_SAP_SNAP ||
316	    (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
317		return htons(ETH_P_802_2);
318
319	__skb_pull(skb, sizeof(struct llc_snap_hdr));
320
321	if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
322		return llc->ethertype;
323
324	return htons(ETH_P_802_2);
325}
326
327static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
328			int nh_len)
329{
330	struct icmp6hdr *icmp = icmp6_hdr(skb);
331
332	/* The ICMPv6 type and code fields use the 16-bit transport port
333	 * fields, so we need to store them in 16-bit network byte order.
334	 */
335	key->ipv6.tp.src = htons(icmp->icmp6_type);
336	key->ipv6.tp.dst = htons(icmp->icmp6_code);
 
337
338	if (icmp->icmp6_code == 0 &&
339	    (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
340	     icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
341		int icmp_len = skb->len - skb_transport_offset(skb);
342		struct nd_msg *nd;
343		int offset;
344
345		/* In order to process neighbor discovery options, we need the
346		 * entire packet.
347		 */
348		if (unlikely(icmp_len < sizeof(*nd)))
349			return 0;
350
351		if (unlikely(skb_linearize(skb)))
352			return -ENOMEM;
353
354		nd = (struct nd_msg *)skb_transport_header(skb);
355		key->ipv6.nd.target = nd->target;
356
357		icmp_len -= sizeof(*nd);
358		offset = 0;
359		while (icmp_len >= 8) {
360			struct nd_opt_hdr *nd_opt =
361				 (struct nd_opt_hdr *)(nd->opt + offset);
362			int opt_len = nd_opt->nd_opt_len * 8;
363
364			if (unlikely(!opt_len || opt_len > icmp_len))
365				return 0;
366
367			/* Store the link layer address if the appropriate
368			 * option is provided.  It is considered an error if
369			 * the same link layer option is specified twice.
370			 */
371			if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
372			    && opt_len == 8) {
373				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
374					goto invalid;
375				memcpy(key->ipv6.nd.sll,
376				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
377			} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
378				   && opt_len == 8) {
379				if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
380					goto invalid;
381				memcpy(key->ipv6.nd.tll,
382				    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
383			}
384
385			icmp_len -= opt_len;
386			offset += opt_len;
387		}
388	}
389
390	return 0;
391
392invalid:
393	memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
394	memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
395	memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
396
397	return 0;
398}
399
400/**
401 * ovs_flow_extract - extracts a flow key from an Ethernet frame.
402 * @skb: sk_buff that contains the frame, with skb->data pointing to the
403 * Ethernet header
404 * @in_port: port number on which @skb was received.
405 * @key: output flow key
406 *
407 * The caller must ensure that skb->len >= ETH_HLEN.
408 *
409 * Returns 0 if successful, otherwise a negative errno value.
410 *
411 * Initializes @skb header pointers as follows:
412 *
413 *    - skb->mac_header: the Ethernet header.
414 *
415 *    - skb->network_header: just past the Ethernet header, or just past the
416 *      VLAN header, to the first byte of the Ethernet payload.
417 *
418 *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
419 *      on output, then just past the IP header, if one is present and
420 *      of a correct length, otherwise the same as skb->network_header.
421 *      For other key->eth.type values it is left untouched.
422 */
423int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key)
424{
425	int error;
426	struct ethhdr *eth;
 
 
427
428	memset(key, 0, sizeof(*key));
 
 
429
430	key->phy.priority = skb->priority;
431	if (OVS_CB(skb)->tun_key)
432		memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
433	key->phy.in_port = in_port;
434	key->phy.skb_mark = skb->mark;
435
436	skb_reset_mac_header(skb);
 
437
438	/* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
439	 * header in the linear data area.
440	 */
441	eth = eth_hdr(skb);
442	memcpy(key->eth.src, eth->h_source, ETH_ALEN);
443	memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
444
445	__skb_pull(skb, 2 * ETH_ALEN);
446	/* We are going to push all headers that we pull, so no need to
447	 * update skb->csum here.
448	 */
449
450	if (vlan_tx_tag_present(skb))
451		key->eth.tci = htons(skb->vlan_tci);
452	else if (eth->h_proto == htons(ETH_P_8021Q))
453		if (unlikely(parse_vlan(skb, key)))
454			return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
455
456	key->eth.type = parse_ethertype(skb);
457	if (unlikely(key->eth.type == htons(0)))
458		return -ENOMEM;
459
460	skb_reset_network_header(skb);
461	__skb_push(skb, skb->data - skb_mac_header(skb));
 
 
 
 
 
 
 
 
462
463	/* Network layer. */
464	if (key->eth.type == htons(ETH_P_IP)) {
465		struct iphdr *nh;
466		__be16 offset;
467
468		error = check_iphdr(skb);
469		if (unlikely(error)) {
 
 
470			if (error == -EINVAL) {
471				skb->transport_header = skb->network_header;
472				error = 0;
473			}
474			return error;
475		}
476
477		nh = ip_hdr(skb);
478		key->ipv4.addr.src = nh->saddr;
479		key->ipv4.addr.dst = nh->daddr;
480
481		key->ip.proto = nh->protocol;
482		key->ip.tos = nh->tos;
483		key->ip.ttl = nh->ttl;
484
485		offset = nh->frag_off & htons(IP_OFFSET);
486		if (offset) {
487			key->ip.frag = OVS_FRAG_TYPE_LATER;
 
488			return 0;
489		}
490		if (nh->frag_off & htons(IP_MF) ||
491			 skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
492			key->ip.frag = OVS_FRAG_TYPE_FIRST;
 
 
493
494		/* Transport layer. */
495		if (key->ip.proto == IPPROTO_TCP) {
496			if (tcphdr_ok(skb)) {
497				struct tcphdr *tcp = tcp_hdr(skb);
498				key->ipv4.tp.src = tcp->source;
499				key->ipv4.tp.dst = tcp->dest;
500				key->ipv4.tp.flags = TCP_FLAGS_BE16(tcp);
 
 
501			}
 
502		} else if (key->ip.proto == IPPROTO_UDP) {
503			if (udphdr_ok(skb)) {
504				struct udphdr *udp = udp_hdr(skb);
505				key->ipv4.tp.src = udp->source;
506				key->ipv4.tp.dst = udp->dest;
 
 
507			}
508		} else if (key->ip.proto == IPPROTO_SCTP) {
509			if (sctphdr_ok(skb)) {
510				struct sctphdr *sctp = sctp_hdr(skb);
511				key->ipv4.tp.src = sctp->source;
512				key->ipv4.tp.dst = sctp->dest;
 
 
513			}
514		} else if (key->ip.proto == IPPROTO_ICMP) {
515			if (icmphdr_ok(skb)) {
516				struct icmphdr *icmp = icmp_hdr(skb);
517				/* The ICMP type and code fields use the 16-bit
518				 * transport port fields, so we need to store
519				 * them in 16-bit network byte order. */
520				key->ipv4.tp.src = htons(icmp->type);
521				key->ipv4.tp.dst = htons(icmp->code);
 
 
522			}
523		}
524
525	} else if ((key->eth.type == htons(ETH_P_ARP) ||
526		   key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
527		struct arp_eth_header *arp;
 
528
529		arp = (struct arp_eth_header *)skb_network_header(skb);
530
531		if (arp->ar_hrd == htons(ARPHRD_ETHER)
532				&& arp->ar_pro == htons(ETH_P_IP)
533				&& arp->ar_hln == ETH_ALEN
534				&& arp->ar_pln == 4) {
 
535
536			/* We only match on the lower 8 bits of the opcode. */
537			if (ntohs(arp->ar_op) <= 0xff)
538				key->ip.proto = ntohs(arp->ar_op);
 
 
 
539			memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
540			memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
541			memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
542			memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
543		}
544	} else if (key->eth.type == htons(ETH_P_IPV6)) {
545		int nh_len;             /* IPv6 Header + Extensions */
546
547		nh_len = parse_ipv6hdr(skb, key);
548		if (unlikely(nh_len < 0)) {
549			if (nh_len == -EINVAL) {
 
 
 
 
 
550				skb->transport_header = skb->network_header;
551				error = 0;
552			} else {
 
553				error = nh_len;
554			}
555			return error;
556		}
557
558		if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 
559			return 0;
 
560		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
561			key->ip.frag = OVS_FRAG_TYPE_FIRST;
562
563		/* Transport layer. */
564		if (key->ip.proto == NEXTHDR_TCP) {
565			if (tcphdr_ok(skb)) {
566				struct tcphdr *tcp = tcp_hdr(skb);
567				key->ipv6.tp.src = tcp->source;
568				key->ipv6.tp.dst = tcp->dest;
569				key->ipv6.tp.flags = TCP_FLAGS_BE16(tcp);
 
 
570			}
571		} else if (key->ip.proto == NEXTHDR_UDP) {
572			if (udphdr_ok(skb)) {
573				struct udphdr *udp = udp_hdr(skb);
574				key->ipv6.tp.src = udp->source;
575				key->ipv6.tp.dst = udp->dest;
 
 
576			}
577		} else if (key->ip.proto == NEXTHDR_SCTP) {
578			if (sctphdr_ok(skb)) {
579				struct sctphdr *sctp = sctp_hdr(skb);
580				key->ipv6.tp.src = sctp->source;
581				key->ipv6.tp.dst = sctp->dest;
 
 
582			}
583		} else if (key->ip.proto == NEXTHDR_ICMP) {
584			if (icmp6hdr_ok(skb)) {
585				error = parse_icmpv6(skb, key, nh_len);
586				if (error)
587					return error;
 
 
588			}
589		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
590	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
591
592	return 0;
593}