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12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/moduleparam.h>
15#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/string.h>
18#include <linux/if_arp.h>
19#include <linux/inetdevice.h>
20#include <linux/inet.h>
21#include <linux/interrupt.h>
22#include <linux/netpoll.h>
23#include <linux/sched.h>
24#include <linux/delay.h>
25#include <linux/rcupdate.h>
26#include <linux/workqueue.h>
27#include <linux/slab.h>
28#include <linux/export.h>
29#include <linux/if_vlan.h>
30#include <net/tcp.h>
31#include <net/udp.h>
32#include <net/addrconf.h>
33#include <net/ndisc.h>
34#include <net/ip6_checksum.h>
35#include <asm/unaligned.h>
36#include <trace/events/napi.h>
37
38
39
40
41
42
43#define MAX_UDP_CHUNK 1460
44#define MAX_SKBS 32
45
46static struct sk_buff_head skb_pool;
47
48static atomic_t trapped;
49
50DEFINE_STATIC_SRCU(netpoll_srcu);
51
52#define USEC_PER_POLL 50
53#define NETPOLL_RX_ENABLED 1
54#define NETPOLL_RX_DROP 2
55
56#define MAX_SKB_SIZE \
57 (sizeof(struct ethhdr) + \
58 sizeof(struct iphdr) + \
59 sizeof(struct udphdr) + \
60 MAX_UDP_CHUNK)
61
62static void zap_completion_queue(void);
63static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo);
64static void netpoll_async_cleanup(struct work_struct *work);
65
66static unsigned int carrier_timeout = 4;
67module_param(carrier_timeout, uint, 0644);
68
69#define np_info(np, fmt, ...) \
70 pr_info("%s: " fmt, np->name, ##__VA_ARGS__)
71#define np_err(np, fmt, ...) \
72 pr_err("%s: " fmt, np->name, ##__VA_ARGS__)
73#define np_notice(np, fmt, ...) \
74 pr_notice("%s: " fmt, np->name, ##__VA_ARGS__)
75
76static void queue_process(struct work_struct *work)
77{
78 struct netpoll_info *npinfo =
79 container_of(work, struct netpoll_info, tx_work.work);
80 struct sk_buff *skb;
81 unsigned long flags;
82
83 while ((skb = skb_dequeue(&npinfo->txq))) {
84 struct net_device *dev = skb->dev;
85 const struct net_device_ops *ops = dev->netdev_ops;
86 struct netdev_queue *txq;
87
88 if (!netif_device_present(dev) || !netif_running(dev)) {
89 __kfree_skb(skb);
90 continue;
91 }
92
93 txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
94
95 local_irq_save(flags);
96 __netif_tx_lock(txq, smp_processor_id());
97 if (netif_xmit_frozen_or_stopped(txq) ||
98 ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) {
99 skb_queue_head(&npinfo->txq, skb);
100 __netif_tx_unlock(txq);
101 local_irq_restore(flags);
102
103 schedule_delayed_work(&npinfo->tx_work, HZ/10);
104 return;
105 }
106 __netif_tx_unlock(txq);
107 local_irq_restore(flags);
108 }
109}
110
111static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
112 unsigned short ulen, __be32 saddr, __be32 daddr)
113{
114 __wsum psum;
115
116 if (uh->check == 0 || skb_csum_unnecessary(skb))
117 return 0;
118
119 psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
120
121 if (skb->ip_summed == CHECKSUM_COMPLETE &&
122 !csum_fold(csum_add(psum, skb->csum)))
123 return 0;
124
125 skb->csum = psum;
126
127 return __skb_checksum_complete(skb);
128}
129
130
131
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133
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135
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140
141
142
143
144
145
146static int poll_one_napi(struct netpoll_info *npinfo,
147 struct napi_struct *napi, int budget)
148{
149 int work;
150
151
152
153
154
155 if (!test_bit(NAPI_STATE_SCHED, &napi->state))
156 return budget;
157
158 npinfo->rx_flags |= NETPOLL_RX_DROP;
159 atomic_inc(&trapped);
160 set_bit(NAPI_STATE_NPSVC, &napi->state);
161
162 work = napi->poll(napi, budget);
163 trace_napi_poll(napi);
164
165 clear_bit(NAPI_STATE_NPSVC, &napi->state);
166 atomic_dec(&trapped);
167 npinfo->rx_flags &= ~NETPOLL_RX_DROP;
168
169 return budget - work;
170}
171
172static void poll_napi(struct net_device *dev)
173{
174 struct napi_struct *napi;
175 int budget = 16;
176
177 list_for_each_entry(napi, &dev->napi_list, dev_list) {
178 if (napi->poll_owner != smp_processor_id() &&
179 spin_trylock(&napi->poll_lock)) {
180 budget = poll_one_napi(rcu_dereference_bh(dev->npinfo),
181 napi, budget);
182 spin_unlock(&napi->poll_lock);
183
184 if (!budget)
185 break;
186 }
187 }
188}
189
190static void service_neigh_queue(struct netpoll_info *npi)
191{
192 if (npi) {
193 struct sk_buff *skb;
194
195 while ((skb = skb_dequeue(&npi->neigh_tx)))
196 netpoll_neigh_reply(skb, npi);
197 }
198}
199
200static void netpoll_poll_dev(struct net_device *dev)
201{
202 const struct net_device_ops *ops;
203 struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
204
205
206
207
208
209 if (down_trylock(&ni->dev_lock))
210 return;
211
212 if (!netif_running(dev)) {
213 up(&ni->dev_lock);
214 return;
215 }
216
217 ops = dev->netdev_ops;
218 if (!ops->ndo_poll_controller) {
219 up(&ni->dev_lock);
220 return;
221 }
222
223
224 ops->ndo_poll_controller(dev);
225
226 poll_napi(dev);
227
228 up(&ni->dev_lock);
229
230 if (dev->flags & IFF_SLAVE) {
231 if (ni) {
232 struct net_device *bond_dev;
233 struct sk_buff *skb;
234 struct netpoll_info *bond_ni;
235
236 bond_dev = netdev_master_upper_dev_get_rcu(dev);
237 bond_ni = rcu_dereference_bh(bond_dev->npinfo);
238 while ((skb = skb_dequeue(&ni->neigh_tx))) {
239 skb->dev = bond_dev;
240 skb_queue_tail(&bond_ni->neigh_tx, skb);
241 }
242 }
243 }
244
245 service_neigh_queue(ni);
246
247 zap_completion_queue();
248}
249
250int netpoll_rx_disable(struct net_device *dev)
251{
252 struct netpoll_info *ni;
253 int idx;
254 might_sleep();
255 idx = srcu_read_lock(&netpoll_srcu);
256 ni = srcu_dereference(dev->npinfo, &netpoll_srcu);
257 if (ni)
258 down(&ni->dev_lock);
259 srcu_read_unlock(&netpoll_srcu, idx);
260 return 0;
261}
262EXPORT_SYMBOL(netpoll_rx_disable);
263
264void netpoll_rx_enable(struct net_device *dev)
265{
266 struct netpoll_info *ni;
267 rcu_read_lock();
268 ni = rcu_dereference(dev->npinfo);
269 if (ni)
270 up(&ni->dev_lock);
271 rcu_read_unlock();
272}
273EXPORT_SYMBOL(netpoll_rx_enable);
274
275static void refill_skbs(void)
276{
277 struct sk_buff *skb;
278 unsigned long flags;
279
280 spin_lock_irqsave(&skb_pool.lock, flags);
281 while (skb_pool.qlen < MAX_SKBS) {
282 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
283 if (!skb)
284 break;
285
286 __skb_queue_tail(&skb_pool, skb);
287 }
288 spin_unlock_irqrestore(&skb_pool.lock, flags);
289}
290
291static void zap_completion_queue(void)
292{
293 unsigned long flags;
294 struct softnet_data *sd = &get_cpu_var(softnet_data);
295
296 if (sd->completion_queue) {
297 struct sk_buff *clist;
298
299 local_irq_save(flags);
300 clist = sd->completion_queue;
301 sd->completion_queue = NULL;
302 local_irq_restore(flags);
303
304 while (clist != NULL) {
305 struct sk_buff *skb = clist;
306 clist = clist->next;
307 if (skb->destructor) {
308 atomic_inc(&skb->users);
309 dev_kfree_skb_any(skb);
310 } else {
311 __kfree_skb(skb);
312 }
313 }
314 }
315
316 put_cpu_var(softnet_data);
317}
318
319static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
320{
321 int count = 0;
322 struct sk_buff *skb;
323
324 zap_completion_queue();
325 refill_skbs();
326repeat:
327
328 skb = alloc_skb(len, GFP_ATOMIC);
329 if (!skb)
330 skb = skb_dequeue(&skb_pool);
331
332 if (!skb) {
333 if (++count < 10) {
334 netpoll_poll_dev(np->dev);
335 goto repeat;
336 }
337 return NULL;
338 }
339
340 atomic_set(&skb->users, 1);
341 skb_reserve(skb, reserve);
342 return skb;
343}
344
345static int netpoll_owner_active(struct net_device *dev)
346{
347 struct napi_struct *napi;
348
349 list_for_each_entry(napi, &dev->napi_list, dev_list) {
350 if (napi->poll_owner == smp_processor_id())
351 return 1;
352 }
353 return 0;
354}
355
356
357void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
358 struct net_device *dev)
359{
360 int status = NETDEV_TX_BUSY;
361 unsigned long tries;
362 const struct net_device_ops *ops = dev->netdev_ops;
363
364 struct netpoll_info *npinfo;
365
366 WARN_ON_ONCE(!irqs_disabled());
367
368 npinfo = rcu_dereference_bh(np->dev->npinfo);
369 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
370 __kfree_skb(skb);
371 return;
372 }
373
374
375 if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
376 struct netdev_queue *txq;
377
378 txq = netdev_pick_tx(dev, skb);
379
380
381 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
382 tries > 0; --tries) {
383 if (__netif_tx_trylock(txq)) {
384 if (!netif_xmit_stopped(txq)) {
385 if (vlan_tx_tag_present(skb) &&
386 !vlan_hw_offload_capable(netif_skb_features(skb),
387 skb->vlan_proto)) {
388 skb = __vlan_put_tag(skb, skb->vlan_proto, vlan_tx_tag_get(skb));
389 if (unlikely(!skb))
390 break;
391 skb->vlan_tci = 0;
392 }
393
394 status = ops->ndo_start_xmit(skb, dev);
395 if (status == NETDEV_TX_OK)
396 txq_trans_update(txq);
397 }
398 __netif_tx_unlock(txq);
399
400 if (status == NETDEV_TX_OK)
401 break;
402
403 }
404
405
406 netpoll_poll_dev(np->dev);
407
408 udelay(USEC_PER_POLL);
409 }
410
411 WARN_ONCE(!irqs_disabled(),
412 "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n",
413 dev->name, ops->ndo_start_xmit);
414
415 }
416
417 if (status != NETDEV_TX_OK) {
418 skb_queue_tail(&npinfo->txq, skb);
419 schedule_delayed_work(&npinfo->tx_work,0);
420 }
421}
422EXPORT_SYMBOL(netpoll_send_skb_on_dev);
423
424void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
425{
426 int total_len, ip_len, udp_len;
427 struct sk_buff *skb;
428 struct udphdr *udph;
429 struct iphdr *iph;
430 struct ethhdr *eth;
431 static atomic_t ip_ident;
432 struct ipv6hdr *ip6h;
433
434 udp_len = len + sizeof(*udph);
435 if (np->ipv6)
436 ip_len = udp_len + sizeof(*ip6h);
437 else
438 ip_len = udp_len + sizeof(*iph);
439
440 total_len = ip_len + LL_RESERVED_SPACE(np->dev);
441
442 skb = find_skb(np, total_len + np->dev->needed_tailroom,
443 total_len - len);
444 if (!skb)
445 return;
446
447 skb_copy_to_linear_data(skb, msg, len);
448 skb_put(skb, len);
449
450 skb_push(skb, sizeof(*udph));
451 skb_reset_transport_header(skb);
452 udph = udp_hdr(skb);
453 udph->source = htons(np->local_port);
454 udph->dest = htons(np->remote_port);
455 udph->len = htons(udp_len);
456
457 if (np->ipv6) {
458 udph->check = 0;
459 udph->check = csum_ipv6_magic(&np->local_ip.in6,
460 &np->remote_ip.in6,
461 udp_len, IPPROTO_UDP,
462 csum_partial(udph, udp_len, 0));
463 if (udph->check == 0)
464 udph->check = CSUM_MANGLED_0;
465
466 skb_push(skb, sizeof(*ip6h));
467 skb_reset_network_header(skb);
468 ip6h = ipv6_hdr(skb);
469
470
471 put_unaligned(0x60, (unsigned char *)ip6h);
472 ip6h->flow_lbl[0] = 0;
473 ip6h->flow_lbl[1] = 0;
474 ip6h->flow_lbl[2] = 0;
475
476 ip6h->payload_len = htons(sizeof(struct udphdr) + len);
477 ip6h->nexthdr = IPPROTO_UDP;
478 ip6h->hop_limit = 32;
479 ip6h->saddr = np->local_ip.in6;
480 ip6h->daddr = np->remote_ip.in6;
481
482 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
483 skb_reset_mac_header(skb);
484 skb->protocol = eth->h_proto = htons(ETH_P_IPV6);
485 } else {
486 udph->check = 0;
487 udph->check = csum_tcpudp_magic(np->local_ip.ip,
488 np->remote_ip.ip,
489 udp_len, IPPROTO_UDP,
490 csum_partial(udph, udp_len, 0));
491 if (udph->check == 0)
492 udph->check = CSUM_MANGLED_0;
493
494 skb_push(skb, sizeof(*iph));
495 skb_reset_network_header(skb);
496 iph = ip_hdr(skb);
497
498
499 put_unaligned(0x45, (unsigned char *)iph);
500 iph->tos = 0;
501 put_unaligned(htons(ip_len), &(iph->tot_len));
502 iph->id = htons(atomic_inc_return(&ip_ident));
503 iph->frag_off = 0;
504 iph->ttl = 64;
505 iph->protocol = IPPROTO_UDP;
506 iph->check = 0;
507 put_unaligned(np->local_ip.ip, &(iph->saddr));
508 put_unaligned(np->remote_ip.ip, &(iph->daddr));
509 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
510
511 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
512 skb_reset_mac_header(skb);
513 skb->protocol = eth->h_proto = htons(ETH_P_IP);
514 }
515
516 memcpy(eth->h_source, np->dev->dev_addr, ETH_ALEN);
517 memcpy(eth->h_dest, np->remote_mac, ETH_ALEN);
518
519 skb->dev = np->dev;
520
521 netpoll_send_skb(np, skb);
522}
523EXPORT_SYMBOL(netpoll_send_udp);
524
525static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo)
526{
527 int size, type = ARPOP_REPLY;
528 __be32 sip, tip;
529 unsigned char *sha;
530 struct sk_buff *send_skb;
531 struct netpoll *np, *tmp;
532 unsigned long flags;
533 int hlen, tlen;
534 int hits = 0, proto;
535
536 if (list_empty(&npinfo->rx_np))
537 return;
538
539
540
541 spin_lock_irqsave(&npinfo->rx_lock, flags);
542 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
543 if (np->dev == skb->dev)
544 hits++;
545 }
546 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
547
548
549 if (!hits)
550 return;
551
552 proto = ntohs(eth_hdr(skb)->h_proto);
553 if (proto == ETH_P_IP) {
554 struct arphdr *arp;
555 unsigned char *arp_ptr;
556
557 if (skb->dev->flags & IFF_NOARP)
558 return;
559
560 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
561 return;
562
563 skb_reset_network_header(skb);
564 skb_reset_transport_header(skb);
565 arp = arp_hdr(skb);
566
567 if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
568 arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
569 arp->ar_pro != htons(ETH_P_IP) ||
570 arp->ar_op != htons(ARPOP_REQUEST))
571 return;
572
573 arp_ptr = (unsigned char *)(arp+1);
574
575 sha = arp_ptr;
576 arp_ptr += skb->dev->addr_len;
577 memcpy(&sip, arp_ptr, 4);
578 arp_ptr += 4;
579
580
581 arp_ptr += skb->dev->addr_len;
582 memcpy(&tip, arp_ptr, 4);
583
584
585 if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
586 return;
587
588 size = arp_hdr_len(skb->dev);
589
590 spin_lock_irqsave(&npinfo->rx_lock, flags);
591 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
592 if (tip != np->local_ip.ip)
593 continue;
594
595 hlen = LL_RESERVED_SPACE(np->dev);
596 tlen = np->dev->needed_tailroom;
597 send_skb = find_skb(np, size + hlen + tlen, hlen);
598 if (!send_skb)
599 continue;
600
601 skb_reset_network_header(send_skb);
602 arp = (struct arphdr *) skb_put(send_skb, size);
603 send_skb->dev = skb->dev;
604 send_skb->protocol = htons(ETH_P_ARP);
605
606
607 if (dev_hard_header(send_skb, skb->dev, ETH_P_ARP,
608 sha, np->dev->dev_addr,
609 send_skb->len) < 0) {
610 kfree_skb(send_skb);
611 continue;
612 }
613
614
615
616
617
618
619
620
621
622 arp->ar_hrd = htons(np->dev->type);
623 arp->ar_pro = htons(ETH_P_IP);
624 arp->ar_hln = np->dev->addr_len;
625 arp->ar_pln = 4;
626 arp->ar_op = htons(type);
627
628 arp_ptr = (unsigned char *)(arp + 1);
629 memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
630 arp_ptr += np->dev->addr_len;
631 memcpy(arp_ptr, &tip, 4);
632 arp_ptr += 4;
633 memcpy(arp_ptr, sha, np->dev->addr_len);
634 arp_ptr += np->dev->addr_len;
635 memcpy(arp_ptr, &sip, 4);
636
637 netpoll_send_skb(np, send_skb);
638
639
640
641 break;
642 }
643 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
644 } else if( proto == ETH_P_IPV6) {
645#if IS_ENABLED(CONFIG_IPV6)
646 struct nd_msg *msg;
647 u8 *lladdr = NULL;
648 struct ipv6hdr *hdr;
649 struct icmp6hdr *icmp6h;
650 const struct in6_addr *saddr;
651 const struct in6_addr *daddr;
652 struct inet6_dev *in6_dev = NULL;
653 struct in6_addr *target;
654
655 in6_dev = in6_dev_get(skb->dev);
656 if (!in6_dev || !in6_dev->cnf.accept_ra)
657 return;
658
659 if (!pskb_may_pull(skb, skb->len))
660 return;
661
662 msg = (struct nd_msg *)skb_transport_header(skb);
663
664 __skb_push(skb, skb->data - skb_transport_header(skb));
665
666 if (ipv6_hdr(skb)->hop_limit != 255)
667 return;
668 if (msg->icmph.icmp6_code != 0)
669 return;
670 if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
671 return;
672
673 saddr = &ipv6_hdr(skb)->saddr;
674 daddr = &ipv6_hdr(skb)->daddr;
675
676 size = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
677
678 spin_lock_irqsave(&npinfo->rx_lock, flags);
679 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
680 if (!ipv6_addr_equal(daddr, &np->local_ip.in6))
681 continue;
682
683 hlen = LL_RESERVED_SPACE(np->dev);
684 tlen = np->dev->needed_tailroom;
685 send_skb = find_skb(np, size + hlen + tlen, hlen);
686 if (!send_skb)
687 continue;
688
689 send_skb->protocol = htons(ETH_P_IPV6);
690 send_skb->dev = skb->dev;
691
692 skb_reset_network_header(send_skb);
693 skb_put(send_skb, sizeof(struct ipv6hdr));
694 hdr = ipv6_hdr(send_skb);
695
696 *(__be32*)hdr = htonl(0x60000000);
697
698 hdr->payload_len = htons(size);
699 hdr->nexthdr = IPPROTO_ICMPV6;
700 hdr->hop_limit = 255;
701 hdr->saddr = *saddr;
702 hdr->daddr = *daddr;
703
704 send_skb->transport_header = send_skb->tail;
705 skb_put(send_skb, size);
706
707 icmp6h = (struct icmp6hdr *)skb_transport_header(skb);
708 icmp6h->icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
709 icmp6h->icmp6_router = 0;
710 icmp6h->icmp6_solicited = 1;
711 target = (struct in6_addr *)(skb_transport_header(send_skb) + sizeof(struct icmp6hdr));
712 *target = msg->target;
713 icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, size,
714 IPPROTO_ICMPV6,
715 csum_partial(icmp6h,
716 size, 0));
717
718 if (dev_hard_header(send_skb, skb->dev, ETH_P_IPV6,
719 lladdr, np->dev->dev_addr,
720 send_skb->len) < 0) {
721 kfree_skb(send_skb);
722 continue;
723 }
724
725 netpoll_send_skb(np, send_skb);
726
727
728
729 break;
730 }
731 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
732#endif
733 }
734}
735
736static bool pkt_is_ns(struct sk_buff *skb)
737{
738 struct nd_msg *msg;
739 struct ipv6hdr *hdr;
740
741 if (skb->protocol != htons(ETH_P_ARP))
742 return false;
743 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + sizeof(struct nd_msg)))
744 return false;
745
746 msg = (struct nd_msg *)skb_transport_header(skb);
747 __skb_push(skb, skb->data - skb_transport_header(skb));
748 hdr = ipv6_hdr(skb);
749
750 if (hdr->nexthdr != IPPROTO_ICMPV6)
751 return false;
752 if (hdr->hop_limit != 255)
753 return false;
754 if (msg->icmph.icmp6_code != 0)
755 return false;
756 if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
757 return false;
758
759 return true;
760}
761
762int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo)
763{
764 int proto, len, ulen;
765 int hits = 0;
766 const struct iphdr *iph;
767 struct udphdr *uh;
768 struct netpoll *np, *tmp;
769
770 if (list_empty(&npinfo->rx_np))
771 goto out;
772
773 if (skb->dev->type != ARPHRD_ETHER)
774 goto out;
775
776
777 if (skb->protocol == htons(ETH_P_ARP) && atomic_read(&trapped)) {
778 skb_queue_tail(&npinfo->neigh_tx, skb);
779 return 1;
780 } else if (pkt_is_ns(skb) && atomic_read(&trapped)) {
781 skb_queue_tail(&npinfo->neigh_tx, skb);
782 return 1;
783 }
784
785 if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
786 skb = vlan_untag(skb);
787 if (unlikely(!skb))
788 goto out;
789 }
790
791 proto = ntohs(eth_hdr(skb)->h_proto);
792 if (proto != ETH_P_IP && proto != ETH_P_IPV6)
793 goto out;
794 if (skb->pkt_type == PACKET_OTHERHOST)
795 goto out;
796 if (skb_shared(skb))
797 goto out;
798
799 if (proto == ETH_P_IP) {
800 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
801 goto out;
802 iph = (struct iphdr *)skb->data;
803 if (iph->ihl < 5 || iph->version != 4)
804 goto out;
805 if (!pskb_may_pull(skb, iph->ihl*4))
806 goto out;
807 iph = (struct iphdr *)skb->data;
808 if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
809 goto out;
810
811 len = ntohs(iph->tot_len);
812 if (skb->len < len || len < iph->ihl*4)
813 goto out;
814
815
816
817
818
819 if (pskb_trim_rcsum(skb, len))
820 goto out;
821
822 iph = (struct iphdr *)skb->data;
823 if (iph->protocol != IPPROTO_UDP)
824 goto out;
825
826 len -= iph->ihl*4;
827 uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
828 ulen = ntohs(uh->len);
829
830 if (ulen != len)
831 goto out;
832 if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
833 goto out;
834 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
835 if (np->local_ip.ip && np->local_ip.ip != iph->daddr)
836 continue;
837 if (np->remote_ip.ip && np->remote_ip.ip != iph->saddr)
838 continue;
839 if (np->local_port && np->local_port != ntohs(uh->dest))
840 continue;
841
842 np->rx_hook(np, ntohs(uh->source),
843 (char *)(uh+1),
844 ulen - sizeof(struct udphdr));
845 hits++;
846 }
847 } else {
848#if IS_ENABLED(CONFIG_IPV6)
849 const struct ipv6hdr *ip6h;
850
851 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
852 goto out;
853 ip6h = (struct ipv6hdr *)skb->data;
854 if (ip6h->version != 6)
855 goto out;
856 len = ntohs(ip6h->payload_len);
857 if (!len)
858 goto out;
859 if (len + sizeof(struct ipv6hdr) > skb->len)
860 goto out;
861 if (pskb_trim_rcsum(skb, len + sizeof(struct ipv6hdr)))
862 goto out;
863 ip6h = ipv6_hdr(skb);
864 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
865 goto out;
866 uh = udp_hdr(skb);
867 ulen = ntohs(uh->len);
868 if (ulen != skb->len)
869 goto out;
870 if (udp6_csum_init(skb, uh, IPPROTO_UDP))
871 goto out;
872 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
873 if (!ipv6_addr_equal(&np->local_ip.in6, &ip6h->daddr))
874 continue;
875 if (!ipv6_addr_equal(&np->remote_ip.in6, &ip6h->saddr))
876 continue;
877 if (np->local_port && np->local_port != ntohs(uh->dest))
878 continue;
879
880 np->rx_hook(np, ntohs(uh->source),
881 (char *)(uh+1),
882 ulen - sizeof(struct udphdr));
883 hits++;
884 }
885#endif
886 }
887
888 if (!hits)
889 goto out;
890
891 kfree_skb(skb);
892 return 1;
893
894out:
895 if (atomic_read(&trapped)) {
896 kfree_skb(skb);
897 return 1;
898 }
899
900 return 0;
901}
902
903void netpoll_print_options(struct netpoll *np)
904{
905 np_info(np, "local port %d\n", np->local_port);
906 if (np->ipv6)
907 np_info(np, "local IPv6 address %pI6c\n", &np->local_ip.in6);
908 else
909 np_info(np, "local IPv4 address %pI4\n", &np->local_ip.ip);
910 np_info(np, "interface '%s'\n", np->dev_name);
911 np_info(np, "remote port %d\n", np->remote_port);
912 if (np->ipv6)
913 np_info(np, "remote IPv6 address %pI6c\n", &np->remote_ip.in6);
914 else
915 np_info(np, "remote IPv4 address %pI4\n", &np->remote_ip.ip);
916 np_info(np, "remote ethernet address %pM\n", np->remote_mac);
917}
918EXPORT_SYMBOL(netpoll_print_options);
919
920static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr)
921{
922 const char *end;
923
924 if (!strchr(str, ':') &&
925 in4_pton(str, -1, (void *)addr, -1, &end) > 0) {
926 if (!*end)
927 return 0;
928 }
929 if (in6_pton(str, -1, addr->in6.s6_addr, -1, &end) > 0) {
930#if IS_ENABLED(CONFIG_IPV6)
931 if (!*end)
932 return 1;
933#else
934 return -1;
935#endif
936 }
937 return -1;
938}
939
940int netpoll_parse_options(struct netpoll *np, char *opt)
941{
942 char *cur=opt, *delim;
943 int ipv6;
944
945 if (*cur != '@') {
946 if ((delim = strchr(cur, '@')) == NULL)
947 goto parse_failed;
948 *delim = 0;
949 if (kstrtou16(cur, 10, &np->local_port))
950 goto parse_failed;
951 cur = delim;
952 }
953 cur++;
954
955 if (*cur != '/') {
956 if ((delim = strchr(cur, '/')) == NULL)
957 goto parse_failed;
958 *delim = 0;
959 ipv6 = netpoll_parse_ip_addr(cur, &np->local_ip);
960 if (ipv6 < 0)
961 goto parse_failed;
962 else
963 np->ipv6 = (bool)ipv6;
964 cur = delim;
965 }
966 cur++;
967
968 if (*cur != ',') {
969
970 if ((delim = strchr(cur, ',')) == NULL)
971 goto parse_failed;
972 *delim = 0;
973 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
974 cur = delim;
975 }
976 cur++;
977
978 if (*cur != '@') {
979
980 if ((delim = strchr(cur, '@')) == NULL)
981 goto parse_failed;
982 *delim = 0;
983 if (*cur == ' ' || *cur == '\t')
984 np_info(np, "warning: whitespace is not allowed\n");
985 if (kstrtou16(cur, 10, &np->remote_port))
986 goto parse_failed;
987 cur = delim;
988 }
989 cur++;
990
991
992 if ((delim = strchr(cur, '/')) == NULL)
993 goto parse_failed;
994 *delim = 0;
995 ipv6 = netpoll_parse_ip_addr(cur, &np->remote_ip);
996 if (ipv6 < 0)
997 goto parse_failed;
998 else if (np->ipv6 != (bool)ipv6)
999 goto parse_failed;
1000 else
1001 np->ipv6 = (bool)ipv6;
1002 cur = delim + 1;
1003
1004 if (*cur != 0) {
1005
1006 if (!mac_pton(cur, np->remote_mac))
1007 goto parse_failed;
1008 }
1009
1010 netpoll_print_options(np);
1011
1012 return 0;
1013
1014 parse_failed:
1015 np_info(np, "couldn't parse config at '%s'!\n", cur);
1016 return -1;
1017}
1018EXPORT_SYMBOL(netpoll_parse_options);
1019
1020int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
1021{
1022 struct netpoll_info *npinfo;
1023 const struct net_device_ops *ops;
1024 unsigned long flags;
1025 int err;
1026
1027 np->dev = ndev;
1028 strlcpy(np->dev_name, ndev->name, IFNAMSIZ);
1029 INIT_WORK(&np->cleanup_work, netpoll_async_cleanup);
1030
1031 if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
1032 !ndev->netdev_ops->ndo_poll_controller) {
1033 np_err(np, "%s doesn't support polling, aborting\n",
1034 np->dev_name);
1035 err = -ENOTSUPP;
1036 goto out;
1037 }
1038
1039 if (!ndev->npinfo) {
1040 npinfo = kmalloc(sizeof(*npinfo), gfp);
1041 if (!npinfo) {
1042 err = -ENOMEM;
1043 goto out;
1044 }
1045
1046 npinfo->rx_flags = 0;
1047 INIT_LIST_HEAD(&npinfo->rx_np);
1048
1049 spin_lock_init(&npinfo->rx_lock);
1050 sema_init(&npinfo->dev_lock, 1);
1051 skb_queue_head_init(&npinfo->neigh_tx);
1052 skb_queue_head_init(&npinfo->txq);
1053 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
1054
1055 atomic_set(&npinfo->refcnt, 1);
1056
1057 ops = np->dev->netdev_ops;
1058 if (ops->ndo_netpoll_setup) {
1059 err = ops->ndo_netpoll_setup(ndev, npinfo, gfp);
1060 if (err)
1061 goto free_npinfo;
1062 }
1063 } else {
1064 npinfo = rtnl_dereference(ndev->npinfo);
1065 atomic_inc(&npinfo->refcnt);
1066 }
1067
1068 npinfo->netpoll = np;
1069
1070 if (np->rx_hook) {
1071 spin_lock_irqsave(&npinfo->rx_lock, flags);
1072 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
1073 list_add_tail(&np->rx, &npinfo->rx_np);
1074 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
1075 }
1076
1077
1078 rcu_assign_pointer(ndev->npinfo, npinfo);
1079
1080 return 0;
1081
1082free_npinfo:
1083 kfree(npinfo);
1084out:
1085 return err;
1086}
1087EXPORT_SYMBOL_GPL(__netpoll_setup);
1088
1089int netpoll_setup(struct netpoll *np)
1090{
1091 struct net_device *ndev = NULL;
1092 struct in_device *in_dev;
1093 int err;
1094
1095 rtnl_lock();
1096 if (np->dev_name) {
1097 struct net *net = current->nsproxy->net_ns;
1098 ndev = __dev_get_by_name(net, np->dev_name);
1099 }
1100 if (!ndev) {
1101 np_err(np, "%s doesn't exist, aborting\n", np->dev_name);
1102 err = -ENODEV;
1103 goto unlock;
1104 }
1105 dev_hold(ndev);
1106
1107 if (netdev_master_upper_dev_get(ndev)) {
1108 np_err(np, "%s is a slave device, aborting\n", np->dev_name);
1109 err = -EBUSY;
1110 goto put;
1111 }
1112
1113 if (!netif_running(ndev)) {
1114 unsigned long atmost, atleast;
1115
1116 np_info(np, "device %s not up yet, forcing it\n", np->dev_name);
1117
1118 err = dev_open(ndev);
1119
1120 if (err) {
1121 np_err(np, "failed to open %s\n", ndev->name);
1122 goto put;
1123 }
1124
1125 rtnl_unlock();
1126 atleast = jiffies + HZ/10;
1127 atmost = jiffies + carrier_timeout * HZ;
1128 while (!netif_carrier_ok(ndev)) {
1129 if (time_after(jiffies, atmost)) {
1130 np_notice(np, "timeout waiting for carrier\n");
1131 break;
1132 }
1133 msleep(1);
1134 }
1135
1136
1137
1138
1139
1140
1141 if (time_before(jiffies, atleast)) {
1142 np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n");
1143 msleep(4000);
1144 }
1145 rtnl_lock();
1146 }
1147
1148 if (!np->local_ip.ip) {
1149 if (!np->ipv6) {
1150 in_dev = __in_dev_get_rtnl(ndev);
1151
1152 if (!in_dev || !in_dev->ifa_list) {
1153 np_err(np, "no IP address for %s, aborting\n",
1154 np->dev_name);
1155 err = -EDESTADDRREQ;
1156 goto put;
1157 }
1158
1159 np->local_ip.ip = in_dev->ifa_list->ifa_local;
1160 np_info(np, "local IP %pI4\n", &np->local_ip.ip);
1161 } else {
1162#if IS_ENABLED(CONFIG_IPV6)
1163 struct inet6_dev *idev;
1164
1165 err = -EDESTADDRREQ;
1166 idev = __in6_dev_get(ndev);
1167 if (idev) {
1168 struct inet6_ifaddr *ifp;
1169
1170 read_lock_bh(&idev->lock);
1171 list_for_each_entry(ifp, &idev->addr_list, if_list) {
1172 if (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)
1173 continue;
1174 np->local_ip.in6 = ifp->addr;
1175 err = 0;
1176 break;
1177 }
1178 read_unlock_bh(&idev->lock);
1179 }
1180 if (err) {
1181 np_err(np, "no IPv6 address for %s, aborting\n",
1182 np->dev_name);
1183 goto put;
1184 } else
1185 np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6);
1186#else
1187 np_err(np, "IPv6 is not supported %s, aborting\n",
1188 np->dev_name);
1189 err = -EINVAL;
1190 goto put;
1191#endif
1192 }
1193 }
1194
1195
1196 refill_skbs();
1197
1198 err = __netpoll_setup(np, ndev, GFP_KERNEL);
1199 if (err)
1200 goto put;
1201
1202 rtnl_unlock();
1203 return 0;
1204
1205put:
1206 dev_put(ndev);
1207unlock:
1208 rtnl_unlock();
1209 return err;
1210}
1211EXPORT_SYMBOL(netpoll_setup);
1212
1213static int __init netpoll_init(void)
1214{
1215 skb_queue_head_init(&skb_pool);
1216 return 0;
1217}
1218core_initcall(netpoll_init);
1219
1220static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
1221{
1222 struct netpoll_info *npinfo =
1223 container_of(rcu_head, struct netpoll_info, rcu);
1224
1225 skb_queue_purge(&npinfo->neigh_tx);
1226 skb_queue_purge(&npinfo->txq);
1227
1228
1229 cancel_delayed_work(&npinfo->tx_work);
1230
1231
1232 __skb_queue_purge(&npinfo->txq);
1233
1234 cancel_delayed_work(&npinfo->tx_work);
1235 kfree(npinfo);
1236}
1237
1238void __netpoll_cleanup(struct netpoll *np)
1239{
1240 struct netpoll_info *npinfo;
1241 unsigned long flags;
1242
1243
1244
1245
1246
1247 npinfo = rtnl_dereference(np->dev->npinfo);
1248 if (!npinfo)
1249 return;
1250
1251 if (!list_empty(&npinfo->rx_np)) {
1252 spin_lock_irqsave(&npinfo->rx_lock, flags);
1253 list_del(&np->rx);
1254 if (list_empty(&npinfo->rx_np))
1255 npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
1256 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
1257 }
1258
1259 synchronize_srcu(&netpoll_srcu);
1260
1261 if (atomic_dec_and_test(&npinfo->refcnt)) {
1262 const struct net_device_ops *ops;
1263
1264 ops = np->dev->netdev_ops;
1265 if (ops->ndo_netpoll_cleanup)
1266 ops->ndo_netpoll_cleanup(np->dev);
1267
1268 rcu_assign_pointer(np->dev->npinfo, NULL);
1269 call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
1270 }
1271}
1272EXPORT_SYMBOL_GPL(__netpoll_cleanup);
1273
1274static void netpoll_async_cleanup(struct work_struct *work)
1275{
1276 struct netpoll *np = container_of(work, struct netpoll, cleanup_work);
1277
1278 rtnl_lock();
1279 __netpoll_cleanup(np);
1280 rtnl_unlock();
1281 kfree(np);
1282}
1283
1284void __netpoll_free_async(struct netpoll *np)
1285{
1286 schedule_work(&np->cleanup_work);
1287}
1288EXPORT_SYMBOL_GPL(__netpoll_free_async);
1289
1290void netpoll_cleanup(struct netpoll *np)
1291{
1292 if (!np->dev)
1293 return;
1294
1295 rtnl_lock();
1296 __netpoll_cleanup(np);
1297 rtnl_unlock();
1298
1299 dev_put(np->dev);
1300 np->dev = NULL;
1301}
1302EXPORT_SYMBOL(netpoll_cleanup);
1303
1304int netpoll_trap(void)
1305{
1306 return atomic_read(&trapped);
1307}
1308EXPORT_SYMBOL(netpoll_trap);
1309
1310void netpoll_set_trap(int trap)
1311{
1312 if (trap)
1313 atomic_inc(&trapped);
1314 else
1315 atomic_dec(&trapped);
1316}
1317EXPORT_SYMBOL(netpoll_set_trap);
1318