xref: /linux/drivers/net/ipvlan/ipvlan_core.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
3  */
4 
5 #include <net/inet_dscp.h>
6 #include <net/ip.h>
7 
8 #include "ipvlan.h"
9 
10 static u32 ipvlan_jhash_secret __read_mostly;
11 
12 void ipvlan_init_secret(void)
13 {
14 	net_get_random_once(&ipvlan_jhash_secret, sizeof(ipvlan_jhash_secret));
15 }
16 
17 void ipvlan_count_rx(const struct ipvl_dev *ipvlan,
18 			    unsigned int len, bool success, bool mcast)
19 {
20 	if (likely(success)) {
21 		struct ipvl_pcpu_stats *pcptr;
22 
23 		pcptr = this_cpu_ptr(ipvlan->pcpu_stats);
24 		u64_stats_update_begin(&pcptr->syncp);
25 		u64_stats_inc(&pcptr->rx_pkts);
26 		u64_stats_add(&pcptr->rx_bytes, len);
27 		if (mcast)
28 			u64_stats_inc(&pcptr->rx_mcast);
29 		u64_stats_update_end(&pcptr->syncp);
30 	} else {
31 		this_cpu_inc(ipvlan->pcpu_stats->rx_errs);
32 	}
33 }
34 EXPORT_SYMBOL_GPL(ipvlan_count_rx);
35 
36 #if IS_ENABLED(CONFIG_IPV6)
37 static u8 ipvlan_get_v6_hash(const void *iaddr)
38 {
39 	const struct in6_addr *ip6_addr = iaddr;
40 
41 	return __ipv6_addr_jhash(ip6_addr, ipvlan_jhash_secret) &
42 	       IPVLAN_HASH_MASK;
43 }
44 #else
45 static u8 ipvlan_get_v6_hash(const void *iaddr)
46 {
47 	return 0;
48 }
49 #endif
50 
51 static u8 ipvlan_get_v4_hash(const void *iaddr)
52 {
53 	const struct in_addr *ip4_addr = iaddr;
54 
55 	return jhash_1word(ip4_addr->s_addr, ipvlan_jhash_secret) &
56 	       IPVLAN_HASH_MASK;
57 }
58 
59 static bool addr_equal(bool is_v6, struct ipvl_addr *addr, const void *iaddr)
60 {
61 	if (!is_v6 && addr->atype == IPVL_IPV4) {
62 		struct in_addr *i4addr = (struct in_addr *)iaddr;
63 
64 		return addr->ip4addr.s_addr == i4addr->s_addr;
65 #if IS_ENABLED(CONFIG_IPV6)
66 	} else if (is_v6 && addr->atype == IPVL_IPV6) {
67 		struct in6_addr *i6addr = (struct in6_addr *)iaddr;
68 
69 		return ipv6_addr_equal(&addr->ip6addr, i6addr);
70 #endif
71 	}
72 
73 	return false;
74 }
75 
76 static struct ipvl_addr *ipvlan_ht_addr_lookup(const struct ipvl_port *port,
77 					       const void *iaddr, bool is_v6)
78 {
79 	struct ipvl_addr *addr;
80 	u8 hash;
81 
82 	hash = is_v6 ? ipvlan_get_v6_hash(iaddr) :
83 	       ipvlan_get_v4_hash(iaddr);
84 	hlist_for_each_entry_rcu(addr, &port->hlhead[hash], hlnode)
85 		if (addr_equal(is_v6, addr, iaddr))
86 			return addr;
87 	return NULL;
88 }
89 
90 void ipvlan_ht_addr_add(struct ipvl_dev *ipvlan, struct ipvl_addr *addr)
91 {
92 	struct ipvl_port *port = ipvlan->port;
93 	u8 hash;
94 
95 	hash = (addr->atype == IPVL_IPV6) ?
96 	       ipvlan_get_v6_hash(&addr->ip6addr) :
97 	       ipvlan_get_v4_hash(&addr->ip4addr);
98 	if (hlist_unhashed(&addr->hlnode))
99 		hlist_add_head_rcu(&addr->hlnode, &port->hlhead[hash]);
100 }
101 
102 void ipvlan_ht_addr_del(struct ipvl_addr *addr)
103 {
104 	hlist_del_init_rcu(&addr->hlnode);
105 }
106 
107 struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan,
108 				   const void *iaddr, bool is_v6)
109 {
110 	struct ipvl_addr *addr, *ret = NULL;
111 
112 	rcu_read_lock();
113 	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode) {
114 		if (addr_equal(is_v6, addr, iaddr)) {
115 			ret = addr;
116 			break;
117 		}
118 	}
119 	rcu_read_unlock();
120 	return ret;
121 }
122 
123 bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6)
124 {
125 	struct ipvl_dev *ipvlan;
126 	bool ret = false;
127 
128 	rcu_read_lock();
129 	list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) {
130 		if (ipvlan_find_addr(ipvlan, iaddr, is_v6)) {
131 			ret = true;
132 			break;
133 		}
134 	}
135 	rcu_read_unlock();
136 	return ret;
137 }
138 
139 void *ipvlan_get_L3_hdr(struct ipvl_port *port, struct sk_buff *skb, int *type)
140 {
141 	void *lyr3h = NULL;
142 
143 	switch (skb->protocol) {
144 	case htons(ETH_P_ARP): {
145 		struct arphdr *arph;
146 
147 		if (unlikely(!pskb_may_pull(skb, arp_hdr_len(port->dev))))
148 			return NULL;
149 
150 		arph = arp_hdr(skb);
151 		*type = IPVL_ARP;
152 		lyr3h = arph;
153 		break;
154 	}
155 	case htons(ETH_P_IP): {
156 		u32 pktlen;
157 		struct iphdr *ip4h;
158 
159 		if (unlikely(!pskb_may_pull(skb, sizeof(*ip4h))))
160 			return NULL;
161 
162 		ip4h = ip_hdr(skb);
163 		pktlen = skb_ip_totlen(skb);
164 		if (ip4h->ihl < 5 || ip4h->version != 4)
165 			return NULL;
166 		if (skb->len < pktlen || pktlen < (ip4h->ihl * 4))
167 			return NULL;
168 
169 		*type = IPVL_IPV4;
170 		lyr3h = ip4h;
171 		break;
172 	}
173 #if IS_ENABLED(CONFIG_IPV6)
174 	case htons(ETH_P_IPV6): {
175 		struct ipv6hdr *ip6h;
176 
177 		if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h))))
178 			return NULL;
179 
180 		ip6h = ipv6_hdr(skb);
181 		if (ip6h->version != 6)
182 			return NULL;
183 
184 		*type = IPVL_IPV6;
185 		lyr3h = ip6h;
186 		/* Only Neighbour Solicitation pkts need different treatment */
187 		if (ipv6_addr_any(&ip6h->saddr) &&
188 		    ip6h->nexthdr == NEXTHDR_ICMP) {
189 			struct icmp6hdr	*icmph;
190 
191 			if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph))))
192 				return NULL;
193 
194 			ip6h = ipv6_hdr(skb);
195 			icmph = (struct icmp6hdr *)(ip6h + 1);
196 
197 			if (icmph->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) {
198 				/* Need to access the ipv6 address in body */
199 				if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph)
200 						+ sizeof(struct in6_addr))))
201 					return NULL;
202 
203 				ip6h = ipv6_hdr(skb);
204 				icmph = (struct icmp6hdr *)(ip6h + 1);
205 			}
206 
207 			*type = IPVL_ICMPV6;
208 			lyr3h = icmph;
209 		}
210 		break;
211 	}
212 #endif
213 	default:
214 		return NULL;
215 	}
216 
217 	return lyr3h;
218 }
219 
220 unsigned int ipvlan_mac_hash(const unsigned char *addr)
221 {
222 	u32 hash = jhash_1word(__get_unaligned_cpu32(addr+2),
223 			       ipvlan_jhash_secret);
224 
225 	return hash & IPVLAN_MAC_FILTER_MASK;
226 }
227 
228 void ipvlan_process_multicast(struct work_struct *work)
229 {
230 	struct ipvl_port *port = container_of(work, struct ipvl_port, wq);
231 	struct ethhdr *ethh;
232 	struct ipvl_dev *ipvlan;
233 	struct sk_buff *skb, *nskb;
234 	struct sk_buff_head list;
235 	unsigned int len;
236 	unsigned int mac_hash;
237 	int ret;
238 	u8 pkt_type;
239 	bool tx_pkt;
240 
241 	__skb_queue_head_init(&list);
242 
243 	spin_lock_bh(&port->backlog.lock);
244 	skb_queue_splice_tail_init(&port->backlog, &list);
245 	spin_unlock_bh(&port->backlog.lock);
246 
247 	while ((skb = __skb_dequeue(&list)) != NULL) {
248 		struct net_device *dev = skb->dev;
249 		bool consumed = false;
250 
251 		ethh = eth_hdr(skb);
252 		tx_pkt = IPVL_SKB_CB(skb)->tx_pkt;
253 		mac_hash = ipvlan_mac_hash(ethh->h_dest);
254 
255 		if (ether_addr_equal(ethh->h_dest, port->dev->broadcast))
256 			pkt_type = PACKET_BROADCAST;
257 		else
258 			pkt_type = PACKET_MULTICAST;
259 
260 		rcu_read_lock();
261 		list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) {
262 			if (tx_pkt && (ipvlan->dev == skb->dev))
263 				continue;
264 			if (!test_bit(mac_hash, ipvlan->mac_filters))
265 				continue;
266 			if (!(ipvlan->dev->flags & IFF_UP))
267 				continue;
268 			ret = NET_RX_DROP;
269 			len = skb->len + ETH_HLEN;
270 			nskb = skb_clone(skb, GFP_ATOMIC);
271 			local_bh_disable();
272 			if (nskb) {
273 				consumed = true;
274 				nskb->pkt_type = pkt_type;
275 				nskb->dev = ipvlan->dev;
276 				if (tx_pkt)
277 					ret = dev_forward_skb(ipvlan->dev, nskb);
278 				else
279 					ret = netif_rx(nskb);
280 			}
281 			ipvlan_count_rx(ipvlan, len, ret == NET_RX_SUCCESS, true);
282 			local_bh_enable();
283 		}
284 		rcu_read_unlock();
285 
286 		if (tx_pkt) {
287 			/* If the packet originated here, send it out. */
288 			skb->dev = port->dev;
289 			skb->pkt_type = pkt_type;
290 			dev_queue_xmit(skb);
291 		} else {
292 			if (consumed)
293 				consume_skb(skb);
294 			else
295 				kfree_skb(skb);
296 		}
297 		dev_put(dev);
298 		cond_resched();
299 	}
300 }
301 
302 static void ipvlan_skb_crossing_ns(struct sk_buff *skb, struct net_device *dev)
303 {
304 	bool xnet = true;
305 
306 	if (dev)
307 		xnet = !net_eq(dev_net(skb->dev), dev_net(dev));
308 
309 	skb_scrub_packet(skb, xnet);
310 	if (dev)
311 		skb->dev = dev;
312 }
313 
314 static int ipvlan_rcv_frame(struct ipvl_addr *addr, struct sk_buff **pskb,
315 			    bool local)
316 {
317 	struct ipvl_dev *ipvlan = addr->master;
318 	struct net_device *dev = ipvlan->dev;
319 	unsigned int len;
320 	rx_handler_result_t ret = RX_HANDLER_CONSUMED;
321 	bool success = false;
322 	struct sk_buff *skb = *pskb;
323 
324 	len = skb->len + ETH_HLEN;
325 	/* Only packets exchanged between two local slaves need to have
326 	 * device-up check as well as skb-share check.
327 	 */
328 	if (local) {
329 		if (unlikely(!(dev->flags & IFF_UP))) {
330 			kfree_skb(skb);
331 			goto out;
332 		}
333 
334 		skb = skb_share_check(skb, GFP_ATOMIC);
335 		if (!skb)
336 			goto out;
337 
338 		*pskb = skb;
339 	}
340 
341 	if (local) {
342 		skb->pkt_type = PACKET_HOST;
343 		if (dev_forward_skb(ipvlan->dev, skb) == NET_RX_SUCCESS)
344 			success = true;
345 	} else {
346 		skb->dev = dev;
347 		ret = RX_HANDLER_ANOTHER;
348 		success = true;
349 	}
350 
351 out:
352 	ipvlan_count_rx(ipvlan, len, success, false);
353 	return ret;
354 }
355 
356 struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port, void *lyr3h,
357 				     int addr_type, bool use_dest)
358 {
359 	struct ipvl_addr *addr = NULL;
360 
361 	switch (addr_type) {
362 #if IS_ENABLED(CONFIG_IPV6)
363 	case IPVL_IPV6: {
364 		struct ipv6hdr *ip6h;
365 		struct in6_addr *i6addr;
366 
367 		ip6h = (struct ipv6hdr *)lyr3h;
368 		i6addr = use_dest ? &ip6h->daddr : &ip6h->saddr;
369 		addr = ipvlan_ht_addr_lookup(port, i6addr, true);
370 		break;
371 	}
372 	case IPVL_ICMPV6: {
373 		struct nd_msg *ndmh;
374 		struct in6_addr *i6addr;
375 
376 		/* Make sure that the NeighborSolicitation ICMPv6 packets
377 		 * are handled to avoid DAD issue.
378 		 */
379 		ndmh = (struct nd_msg *)lyr3h;
380 		if (ndmh->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) {
381 			i6addr = &ndmh->target;
382 			addr = ipvlan_ht_addr_lookup(port, i6addr, true);
383 		}
384 		break;
385 	}
386 #endif
387 	case IPVL_IPV4: {
388 		struct iphdr *ip4h;
389 		__be32 *i4addr;
390 
391 		ip4h = (struct iphdr *)lyr3h;
392 		i4addr = use_dest ? &ip4h->daddr : &ip4h->saddr;
393 		addr = ipvlan_ht_addr_lookup(port, i4addr, false);
394 		break;
395 	}
396 	case IPVL_ARP: {
397 		struct arphdr *arph;
398 		unsigned char *arp_ptr;
399 		__be32 dip;
400 
401 		arph = (struct arphdr *)lyr3h;
402 		arp_ptr = (unsigned char *)(arph + 1);
403 		if (use_dest)
404 			arp_ptr += (2 * port->dev->addr_len) + 4;
405 		else
406 			arp_ptr += port->dev->addr_len;
407 
408 		memcpy(&dip, arp_ptr, 4);
409 		addr = ipvlan_ht_addr_lookup(port, &dip, false);
410 		break;
411 	}
412 	}
413 
414 	return addr;
415 }
416 
417 static noinline_for_stack int ipvlan_process_v4_outbound(struct sk_buff *skb)
418 {
419 	const struct iphdr *ip4h = ip_hdr(skb);
420 	struct net_device *dev = skb->dev;
421 	struct net *net = dev_net(dev);
422 	struct rtable *rt;
423 	int err, ret = NET_XMIT_DROP;
424 	struct flowi4 fl4 = {
425 		.flowi4_oif = dev->ifindex,
426 		.flowi4_tos = inet_dscp_to_dsfield(ip4h_dscp(ip4h)),
427 		.flowi4_flags = FLOWI_FLAG_ANYSRC,
428 		.flowi4_mark = skb->mark,
429 		.daddr = ip4h->daddr,
430 		.saddr = ip4h->saddr,
431 	};
432 
433 	rt = ip_route_output_flow(net, &fl4, NULL);
434 	if (IS_ERR(rt))
435 		goto err;
436 
437 	if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
438 		ip_rt_put(rt);
439 		goto err;
440 	}
441 	skb_dst_set(skb, &rt->dst);
442 
443 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
444 
445 	err = ip_local_out(net, NULL, skb);
446 	if (unlikely(net_xmit_eval(err)))
447 		DEV_STATS_INC(dev, tx_errors);
448 	else
449 		ret = NET_XMIT_SUCCESS;
450 	goto out;
451 err:
452 	DEV_STATS_INC(dev, tx_errors);
453 	kfree_skb(skb);
454 out:
455 	return ret;
456 }
457 
458 #if IS_ENABLED(CONFIG_IPV6)
459 
460 static noinline_for_stack int
461 ipvlan_route_v6_outbound(struct net_device *dev, struct sk_buff *skb)
462 {
463 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
464 	struct flowi6 fl6 = {
465 		.flowi6_oif = dev->ifindex,
466 		.daddr = ip6h->daddr,
467 		.saddr = ip6h->saddr,
468 		.flowi6_flags = FLOWI_FLAG_ANYSRC,
469 		.flowlabel = ip6_flowinfo(ip6h),
470 		.flowi6_mark = skb->mark,
471 		.flowi6_proto = ip6h->nexthdr,
472 	};
473 	struct dst_entry *dst;
474 	int err;
475 
476 	dst = ip6_route_output(dev_net(dev), NULL, &fl6);
477 	err = dst->error;
478 	if (err) {
479 		dst_release(dst);
480 		return err;
481 	}
482 	skb_dst_set(skb, dst);
483 	return 0;
484 }
485 
486 static int ipvlan_process_v6_outbound(struct sk_buff *skb)
487 {
488 	struct net_device *dev = skb->dev;
489 	int err, ret = NET_XMIT_DROP;
490 
491 	err = ipvlan_route_v6_outbound(dev, skb);
492 	if (unlikely(err)) {
493 		DEV_STATS_INC(dev, tx_errors);
494 		kfree_skb(skb);
495 		return err;
496 	}
497 
498 	memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
499 
500 	err = ip6_local_out(dev_net(dev), NULL, skb);
501 	if (unlikely(net_xmit_eval(err)))
502 		DEV_STATS_INC(dev, tx_errors);
503 	else
504 		ret = NET_XMIT_SUCCESS;
505 	return ret;
506 }
507 #else
508 static int ipvlan_process_v6_outbound(struct sk_buff *skb)
509 {
510 	return NET_XMIT_DROP;
511 }
512 #endif
513 
514 static int ipvlan_process_outbound(struct sk_buff *skb)
515 {
516 	int ret = NET_XMIT_DROP;
517 
518 	/* The ipvlan is a pseudo-L2 device, so the packets that we receive
519 	 * will have L2; which need to discarded and processed further
520 	 * in the net-ns of the main-device.
521 	 */
522 	if (skb_mac_header_was_set(skb)) {
523 		/* In this mode we dont care about
524 		 * multicast and broadcast traffic */
525 		struct ethhdr *ethh = eth_hdr(skb);
526 
527 		if (is_multicast_ether_addr(ethh->h_dest)) {
528 			pr_debug_ratelimited(
529 				"Dropped {multi|broad}cast of type=[%x]\n",
530 				ntohs(skb->protocol));
531 			kfree_skb(skb);
532 			goto out;
533 		}
534 
535 		skb_pull(skb, sizeof(*ethh));
536 		skb->mac_header = (typeof(skb->mac_header))~0U;
537 		skb_reset_network_header(skb);
538 	}
539 
540 	if (skb->protocol == htons(ETH_P_IPV6))
541 		ret = ipvlan_process_v6_outbound(skb);
542 	else if (skb->protocol == htons(ETH_P_IP))
543 		ret = ipvlan_process_v4_outbound(skb);
544 	else {
545 		pr_warn_ratelimited("Dropped outbound packet type=%x\n",
546 				    ntohs(skb->protocol));
547 		kfree_skb(skb);
548 	}
549 out:
550 	return ret;
551 }
552 
553 static void ipvlan_multicast_enqueue(struct ipvl_port *port,
554 				     struct sk_buff *skb, bool tx_pkt)
555 {
556 	if (skb->protocol == htons(ETH_P_PAUSE)) {
557 		kfree_skb(skb);
558 		return;
559 	}
560 
561 	/* Record that the deferred packet is from TX or RX path. By
562 	 * looking at mac-addresses on packet will lead to erronus decisions.
563 	 * (This would be true for a loopback-mode on master device or a
564 	 * hair-pin mode of the switch.)
565 	 */
566 	IPVL_SKB_CB(skb)->tx_pkt = tx_pkt;
567 
568 	spin_lock(&port->backlog.lock);
569 	if (skb_queue_len(&port->backlog) < IPVLAN_QBACKLOG_LIMIT) {
570 		dev_hold(skb->dev);
571 		__skb_queue_tail(&port->backlog, skb);
572 		spin_unlock(&port->backlog.lock);
573 		schedule_work(&port->wq);
574 	} else {
575 		spin_unlock(&port->backlog.lock);
576 		dev_core_stats_rx_dropped_inc(skb->dev);
577 		kfree_skb(skb);
578 	}
579 }
580 
581 static int ipvlan_xmit_mode_l3(struct sk_buff *skb, struct net_device *dev)
582 {
583 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
584 	void *lyr3h;
585 	struct ipvl_addr *addr;
586 	int addr_type;
587 
588 	lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type);
589 	if (!lyr3h)
590 		goto out;
591 
592 	if (!ipvlan_is_vepa(ipvlan->port)) {
593 		addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
594 		if (addr) {
595 			if (ipvlan_is_private(ipvlan->port)) {
596 				consume_skb(skb);
597 				return NET_XMIT_DROP;
598 			}
599 			ipvlan_rcv_frame(addr, &skb, true);
600 			return NET_XMIT_SUCCESS;
601 		}
602 	}
603 out:
604 	ipvlan_skb_crossing_ns(skb, ipvlan->phy_dev);
605 	return ipvlan_process_outbound(skb);
606 }
607 
608 static int ipvlan_xmit_mode_l2(struct sk_buff *skb, struct net_device *dev)
609 {
610 	const struct ipvl_dev *ipvlan = netdev_priv(dev);
611 	struct ethhdr *eth = skb_eth_hdr(skb);
612 	struct ipvl_addr *addr;
613 	void *lyr3h;
614 	int addr_type;
615 
616 	if (!ipvlan_is_vepa(ipvlan->port) &&
617 	    ether_addr_equal(eth->h_dest, eth->h_source)) {
618 		lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type);
619 		if (lyr3h) {
620 			addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
621 			if (addr) {
622 				if (ipvlan_is_private(ipvlan->port)) {
623 					consume_skb(skb);
624 					return NET_XMIT_DROP;
625 				}
626 				ipvlan_rcv_frame(addr, &skb, true);
627 				return NET_XMIT_SUCCESS;
628 			}
629 		}
630 		skb = skb_share_check(skb, GFP_ATOMIC);
631 		if (!skb)
632 			return NET_XMIT_DROP;
633 
634 		/* Packet definitely does not belong to any of the
635 		 * virtual devices, but the dest is local. So forward
636 		 * the skb for the main-dev. At the RX side we just return
637 		 * RX_PASS for it to be processed further on the stack.
638 		 */
639 		dev_forward_skb(ipvlan->phy_dev, skb);
640 		return NET_XMIT_SUCCESS;
641 
642 	} else if (is_multicast_ether_addr(eth->h_dest)) {
643 		skb_reset_mac_header(skb);
644 		ipvlan_skb_crossing_ns(skb, NULL);
645 		ipvlan_multicast_enqueue(ipvlan->port, skb, true);
646 		return NET_XMIT_SUCCESS;
647 	}
648 
649 	skb->dev = ipvlan->phy_dev;
650 	return dev_queue_xmit(skb);
651 }
652 
653 int ipvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
654 {
655 	struct ipvl_dev *ipvlan = netdev_priv(dev);
656 	struct ipvl_port *port = ipvlan_port_get_rcu_bh(ipvlan->phy_dev);
657 
658 	if (!port)
659 		goto out;
660 
661 	if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
662 		goto out;
663 
664 	switch(port->mode) {
665 	case IPVLAN_MODE_L2:
666 		return ipvlan_xmit_mode_l2(skb, dev);
667 	case IPVLAN_MODE_L3:
668 #ifdef CONFIG_IPVLAN_L3S
669 	case IPVLAN_MODE_L3S:
670 #endif
671 		return ipvlan_xmit_mode_l3(skb, dev);
672 	}
673 
674 	/* Should not reach here */
675 	WARN_ONCE(true, "%s called for mode = [%x]\n", __func__, port->mode);
676 out:
677 	kfree_skb(skb);
678 	return NET_XMIT_DROP;
679 }
680 
681 static bool ipvlan_external_frame(struct sk_buff *skb, struct ipvl_port *port)
682 {
683 	struct ethhdr *eth = eth_hdr(skb);
684 	struct ipvl_addr *addr;
685 	void *lyr3h;
686 	int addr_type;
687 
688 	if (ether_addr_equal(eth->h_source, skb->dev->dev_addr)) {
689 		lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
690 		if (!lyr3h)
691 			return true;
692 
693 		addr = ipvlan_addr_lookup(port, lyr3h, addr_type, false);
694 		if (addr)
695 			return false;
696 	}
697 
698 	return true;
699 }
700 
701 static rx_handler_result_t ipvlan_handle_mode_l3(struct sk_buff **pskb,
702 						 struct ipvl_port *port)
703 {
704 	void *lyr3h;
705 	int addr_type;
706 	struct ipvl_addr *addr;
707 	struct sk_buff *skb = *pskb;
708 	rx_handler_result_t ret = RX_HANDLER_PASS;
709 
710 	lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
711 	if (!lyr3h)
712 		goto out;
713 
714 	addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
715 	if (addr)
716 		ret = ipvlan_rcv_frame(addr, pskb, false);
717 
718 out:
719 	return ret;
720 }
721 
722 static rx_handler_result_t ipvlan_handle_mode_l2(struct sk_buff **pskb,
723 						 struct ipvl_port *port)
724 {
725 	struct sk_buff *skb = *pskb;
726 	struct ethhdr *eth = eth_hdr(skb);
727 	rx_handler_result_t ret = RX_HANDLER_PASS;
728 
729 	if (is_multicast_ether_addr(eth->h_dest)) {
730 		if (ipvlan_external_frame(skb, port)) {
731 			struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
732 
733 			/* External frames are queued for device local
734 			 * distribution, but a copy is given to master
735 			 * straight away to avoid sending duplicates later
736 			 * when work-queue processes this frame. This is
737 			 * achieved by returning RX_HANDLER_PASS.
738 			 */
739 			if (nskb) {
740 				ipvlan_skb_crossing_ns(nskb, NULL);
741 				ipvlan_multicast_enqueue(port, nskb, false);
742 			}
743 		}
744 	} else {
745 		/* Perform like l3 mode for non-multicast packet */
746 		ret = ipvlan_handle_mode_l3(pskb, port);
747 	}
748 
749 	return ret;
750 }
751 
752 rx_handler_result_t ipvlan_handle_frame(struct sk_buff **pskb)
753 {
754 	struct sk_buff *skb = *pskb;
755 	struct ipvl_port *port = ipvlan_port_get_rcu(skb->dev);
756 
757 	if (!port)
758 		return RX_HANDLER_PASS;
759 
760 	switch (port->mode) {
761 	case IPVLAN_MODE_L2:
762 		return ipvlan_handle_mode_l2(pskb, port);
763 	case IPVLAN_MODE_L3:
764 		return ipvlan_handle_mode_l3(pskb, port);
765 #ifdef CONFIG_IPVLAN_L3S
766 	case IPVLAN_MODE_L3S:
767 		return RX_HANDLER_PASS;
768 #endif
769 	}
770 
771 	/* Should not reach here */
772 	WARN_ONCE(true, "%s called for mode = [%x]\n", __func__, port->mode);
773 	kfree_skb(skb);
774 	return RX_HANDLER_CONSUMED;
775 }
776