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kvm tools, setup: Create private directory
[linux-2.6/next.git] / net / packet / af_packet.c
blobc0c3cda19712d3a5a76307f5c85aefc98dc94957
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * PACKET - implements raw packet sockets.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 *
12 * Fixes:
13 * Alan Cox : verify_area() now used correctly
14 * Alan Cox : new skbuff lists, look ma no backlogs!
15 * Alan Cox : tidied skbuff lists.
16 * Alan Cox : Now uses generic datagram routines I
17 * added. Also fixed the peek/read crash
18 * from all old Linux datagram code.
19 * Alan Cox : Uses the improved datagram code.
20 * Alan Cox : Added NULL's for socket options.
21 * Alan Cox : Re-commented the code.
22 * Alan Cox : Use new kernel side addressing
23 * Rob Janssen : Correct MTU usage.
24 * Dave Platt : Counter leaks caused by incorrect
25 * interrupt locking and some slightly
26 * dubious gcc output. Can you read
27 * compiler: it said _VOLATILE_
28 * Richard Kooijman : Timestamp fixes.
29 * Alan Cox : New buffers. Use sk->mac.raw.
30 * Alan Cox : sendmsg/recvmsg support.
31 * Alan Cox : Protocol setting support
32 * Alexey Kuznetsov : Untied from IPv4 stack.
33 * Cyrus Durgin : Fixed kerneld for kmod.
34 * Michal Ostrowski : Module initialization cleanup.
35 * Ulises Alonso : Frame number limit removal and
36 * packet_set_ring memory leak.
37 * Eric Biederman : Allow for > 8 byte hardware addresses.
38 * The convention is that longer addresses
39 * will simply extend the hardware address
40 * byte arrays at the end of sockaddr_ll
41 * and packet_mreq.
42 * Johann Baudy : Added TX RING.
43 *
44 * This program is free software; you can redistribute it and/or
45 * modify it under the terms of the GNU General Public License
46 * as published by the Free Software Foundation; either version
47 * 2 of the License, or (at your option) any later version.
48 *
49 */
50
51 #include <linux/types.h>
52 #include <linux/mm.h>
53 #include <linux/capability.h>
54 #include <linux/fcntl.h>
55 #include <linux/socket.h>
56 #include <linux/in.h>
57 #include <linux/inet.h>
58 #include <linux/netdevice.h>
59 #include <linux/if_packet.h>
60 #include <linux/wireless.h>
61 #include <linux/kernel.h>
62 #include <linux/kmod.h>
63 #include <linux/slab.h>
64 #include <linux/vmalloc.h>
65 #include <net/net_namespace.h>
66 #include <net/ip.h>
67 #include <net/protocol.h>
68 #include <linux/skbuff.h>
69 #include <net/sock.h>
70 #include <linux/errno.h>
71 #include <linux/timer.h>
72 #include <asm/system.h>
73 #include <asm/uaccess.h>
74 #include <asm/ioctls.h>
75 #include <asm/page.h>
76 #include <asm/cacheflush.h>
77 #include <asm/io.h>
78 #include <linux/proc_fs.h>
79 #include <linux/seq_file.h>
80 #include <linux/poll.h>
81 #include <linux/module.h>
82 #include <linux/init.h>
83 #include <linux/mutex.h>
84 #include <linux/if_vlan.h>
85 #include <linux/virtio_net.h>
86 #include <linux/errqueue.h>
87 #include <linux/net_tstamp.h>
88
89 #ifdef CONFIG_INET
90 #include <net/inet_common.h>
91 #endif
92
93 /*
94 Assumptions:
95 - if device has no dev->hard_header routine, it adds and removes ll header
96 inside itself. In this case ll header is invisible outside of device,
97 but higher levels still should reserve dev->hard_header_len.
98 Some devices are enough clever to reallocate skb, when header
99 will not fit to reserved space (tunnel), another ones are silly
100 (PPP).
101 - packet socket receives packets with pulled ll header,
102 so that SOCK_RAW should push it back.
103
104 On receive:
105 -----------
106
107 Incoming, dev->hard_header!=NULL
108 mac_header -> ll header
109 data -> data
110
111 Outgoing, dev->hard_header!=NULL
112 mac_header -> ll header
113 data -> ll header
114
115 Incoming, dev->hard_header==NULL
116 mac_header -> UNKNOWN position. It is very likely, that it points to ll
117 header. PPP makes it, that is wrong, because introduce
118 assymetry between rx and tx paths.
119 data -> data
120
121 Outgoing, dev->hard_header==NULL
122 mac_header -> data. ll header is still not built!
123 data -> data
124
125 Resume
126 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
127
128
129 On transmit:
130 ------------
131
132 dev->hard_header != NULL
133 mac_header -> ll header
134 data -> ll header
135
136 dev->hard_header == NULL (ll header is added by device, we cannot control it)
137 mac_header -> data
138 data -> data
139
140 We should set nh.raw on output to correct posistion,
141 packet classifier depends on it.
142 */
143
144 /* Private packet socket structures. */
145
146 struct packet_mclist {
147 struct packet_mclist *next;
148 int ifindex;
149 int count;
150 unsigned short type;
151 unsigned short alen;
152 unsigned char addr[MAX_ADDR_LEN];
153 };
154 /* identical to struct packet_mreq except it has
155 * a longer address field.
156 */
157 struct packet_mreq_max {
158 int mr_ifindex;
159 unsigned short mr_type;
160 unsigned short mr_alen;
161 unsigned char mr_address[MAX_ADDR_LEN];
162 };
163
164 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
165 int closing, int tx_ring);
166
167 struct pgv {
168 char *buffer;
169 };
170
171 struct packet_ring_buffer {
172 struct pgv *pg_vec;
173 unsigned int head;
174 unsigned int frames_per_block;
175 unsigned int frame_size;
176 unsigned int frame_max;
177
178 unsigned int pg_vec_order;
179 unsigned int pg_vec_pages;
180 unsigned int pg_vec_len;
181
182 atomic_t pending;
183 };
184
185 struct packet_sock;
186 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
187
188 static void packet_flush_mclist(struct sock *sk);
189
190 struct packet_sock {
191 /* struct sock has to be the first member of packet_sock */
192 struct sock sk;
193 struct tpacket_stats stats;
194 struct packet_ring_buffer rx_ring;
195 struct packet_ring_buffer tx_ring;
196 int copy_thresh;
197 spinlock_t bind_lock;
198 struct mutex pg_vec_lock;
199 unsigned int running:1, /* prot_hook is attached*/
200 auxdata:1,
201 origdev:1,
202 has_vnet_hdr:1;
203 int ifindex; /* bound device */
204 __be16 num;
205 struct packet_mclist *mclist;
206 atomic_t mapped;
207 enum tpacket_versions tp_version;
208 unsigned int tp_hdrlen;
209 unsigned int tp_reserve;
210 unsigned int tp_loss:1;
211 unsigned int tp_tstamp;
212 struct packet_type prot_hook ____cacheline_aligned_in_smp;
213 };
214
215 struct packet_skb_cb {
216 unsigned int origlen;
217 union {
218 struct sockaddr_pkt pkt;
219 struct sockaddr_ll ll;
220 } sa;
221 };
222
223 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
224
225 static inline __pure struct page *pgv_to_page(void *addr)
226 {
227 if (is_vmalloc_addr(addr))
228 return vmalloc_to_page(addr);
229 return virt_to_page(addr);
230 }
231
232 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
233 {
234 union {
235 struct tpacket_hdr *h1;
236 struct tpacket2_hdr *h2;
237 void *raw;
238 } h;
239
240 h.raw = frame;
241 switch (po->tp_version) {
242 case TPACKET_V1:
243 h.h1->tp_status = status;
244 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
245 break;
246 case TPACKET_V2:
247 h.h2->tp_status = status;
248 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
249 break;
250 default:
251 pr_err("TPACKET version not supported\n");
252 BUG();
253 }
254
255 smp_wmb();
256 }
257
258 static int __packet_get_status(struct packet_sock *po, void *frame)
259 {
260 union {
261 struct tpacket_hdr *h1;
262 struct tpacket2_hdr *h2;
263 void *raw;
264 } h;
265
266 smp_rmb();
267
268 h.raw = frame;
269 switch (po->tp_version) {
270 case TPACKET_V1:
271 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
272 return h.h1->tp_status;
273 case TPACKET_V2:
274 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
275 return h.h2->tp_status;
276 default:
277 pr_err("TPACKET version not supported\n");
278 BUG();
279 return 0;
280 }
281 }
282
283 static void *packet_lookup_frame(struct packet_sock *po,
284 struct packet_ring_buffer *rb,
285 unsigned int position,
286 int status)
287 {
288 unsigned int pg_vec_pos, frame_offset;
289 union {
290 struct tpacket_hdr *h1;
291 struct tpacket2_hdr *h2;
292 void *raw;
293 } h;
294
295 pg_vec_pos = position / rb->frames_per_block;
296 frame_offset = position % rb->frames_per_block;
297
298 h.raw = rb->pg_vec[pg_vec_pos].buffer +
299 (frame_offset * rb->frame_size);
300
301 if (status != __packet_get_status(po, h.raw))
302 return NULL;
303
304 return h.raw;
305 }
306
307 static inline void *packet_current_frame(struct packet_sock *po,
308 struct packet_ring_buffer *rb,
309 int status)
310 {
311 return packet_lookup_frame(po, rb, rb->head, status);
312 }
313
314 static inline void *packet_previous_frame(struct packet_sock *po,
315 struct packet_ring_buffer *rb,
316 int status)
317 {
318 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
319 return packet_lookup_frame(po, rb, previous, status);
320 }
321
322 static inline void packet_increment_head(struct packet_ring_buffer *buff)
323 {
324 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
325 }
326
327 static inline struct packet_sock *pkt_sk(struct sock *sk)
328 {
329 return (struct packet_sock *)sk;
330 }
331
332 static void packet_sock_destruct(struct sock *sk)
333 {
334 skb_queue_purge(&sk->sk_error_queue);
335
336 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
337 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
338
339 if (!sock_flag(sk, SOCK_DEAD)) {
340 pr_err("Attempt to release alive packet socket: %p\n", sk);
341 return;
342 }
343
344 sk_refcnt_debug_dec(sk);
345 }
346
347
348 static const struct proto_ops packet_ops;
349
350 static const struct proto_ops packet_ops_spkt;
351
352 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
353 struct packet_type *pt, struct net_device *orig_dev)
354 {
355 struct sock *sk;
356 struct sockaddr_pkt *spkt;
357
358 /*
359 * When we registered the protocol we saved the socket in the data
360 * field for just this event.
361 */
362
363 sk = pt->af_packet_priv;
364
365 /*
366 * Yank back the headers [hope the device set this
367 * right or kerboom...]
368 *
369 * Incoming packets have ll header pulled,
370 * push it back.
371 *
372 * For outgoing ones skb->data == skb_mac_header(skb)
373 * so that this procedure is noop.
374 */
375
376 if (skb->pkt_type == PACKET_LOOPBACK)
377 goto out;
378
379 if (!net_eq(dev_net(dev), sock_net(sk)))
380 goto out;
381
382 skb = skb_share_check(skb, GFP_ATOMIC);
383 if (skb == NULL)
384 goto oom;
385
386 /* drop any routing info */
387 skb_dst_drop(skb);
388
389 /* drop conntrack reference */
390 nf_reset(skb);
391
392 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
393
394 skb_push(skb, skb->data - skb_mac_header(skb));
395
396 /*
397 * The SOCK_PACKET socket receives _all_ frames.
398 */
399
400 spkt->spkt_family = dev->type;
401 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
402 spkt->spkt_protocol = skb->protocol;
403
404 /*
405 * Charge the memory to the socket. This is done specifically
406 * to prevent sockets using all the memory up.
407 */
408
409 if (sock_queue_rcv_skb(sk, skb) == 0)
410 return 0;
411
412 out:
413 kfree_skb(skb);
414 oom:
415 return 0;
416 }
417
418
419 /*
420 * Output a raw packet to a device layer. This bypasses all the other
421 * protocol layers and you must therefore supply it with a complete frame
422 */
423
424 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
425 struct msghdr *msg, size_t len)
426 {
427 struct sock *sk = sock->sk;
428 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
429 struct sk_buff *skb = NULL;
430 struct net_device *dev;
431 __be16 proto = 0;
432 int err;
433
434 /*
435 * Get and verify the address.
436 */
437
438 if (saddr) {
439 if (msg->msg_namelen < sizeof(struct sockaddr))
440 return -EINVAL;
441 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
442 proto = saddr->spkt_protocol;
443 } else
444 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
445
446 /*
447 * Find the device first to size check it
448 */
449
450 saddr->spkt_device[13] = 0;
451 retry:
452 rcu_read_lock();
453 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
454 err = -ENODEV;
455 if (dev == NULL)
456 goto out_unlock;
457
458 err = -ENETDOWN;
459 if (!(dev->flags & IFF_UP))
460 goto out_unlock;
461
462 /*
463 * You may not queue a frame bigger than the mtu. This is the lowest level
464 * raw protocol and you must do your own fragmentation at this level.
465 */
466
467 err = -EMSGSIZE;
468 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
469 goto out_unlock;
470
471 if (!skb) {
472 size_t reserved = LL_RESERVED_SPACE(dev);
473 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
474
475 rcu_read_unlock();
476 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
477 if (skb == NULL)
478 return -ENOBUFS;
479 /* FIXME: Save some space for broken drivers that write a hard
480 * header at transmission time by themselves. PPP is the notable
481 * one here. This should really be fixed at the driver level.
482 */
483 skb_reserve(skb, reserved);
484 skb_reset_network_header(skb);
485
486 /* Try to align data part correctly */
487 if (hhlen) {
488 skb->data -= hhlen;
489 skb->tail -= hhlen;
490 if (len < hhlen)
491 skb_reset_network_header(skb);
492 }
493 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
494 if (err)
495 goto out_free;
496 goto retry;
497 }
498
499 if (len > (dev->mtu + dev->hard_header_len)) {
500 /* Earlier code assumed this would be a VLAN pkt,
501 * double-check this now that we have the actual
502 * packet in hand.
503 */
504 struct ethhdr *ehdr;
505 skb_reset_mac_header(skb);
506 ehdr = eth_hdr(skb);
507 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
508 err = -EMSGSIZE;
509 goto out_unlock;
510 }
511 }
512
513 skb->protocol = proto;
514 skb->dev = dev;
515 skb->priority = sk->sk_priority;
516 skb->mark = sk->sk_mark;
517 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
518 if (err < 0)
519 goto out_unlock;
520
521 dev_queue_xmit(skb);
522 rcu_read_unlock();
523 return len;
524
525 out_unlock:
526 rcu_read_unlock();
527 out_free:
528 kfree_skb(skb);
529 return err;
530 }
531
532 static inline unsigned int run_filter(const struct sk_buff *skb,
533 const struct sock *sk,
534 unsigned int res)
535 {
536 struct sk_filter *filter;
537
538 rcu_read_lock();
539 filter = rcu_dereference(sk->sk_filter);
540 if (filter != NULL)
541 res = SK_RUN_FILTER(filter, skb);
542 rcu_read_unlock();
543
544 return res;
545 }
546
547 /*
548 * This function makes lazy skb cloning in hope that most of packets
549 * are discarded by BPF.
550 *
551 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
552 * and skb->cb are mangled. It works because (and until) packets
553 * falling here are owned by current CPU. Output packets are cloned
554 * by dev_queue_xmit_nit(), input packets are processed by net_bh
555 * sequencially, so that if we return skb to original state on exit,
556 * we will not harm anyone.
557 */
558
559 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
560 struct packet_type *pt, struct net_device *orig_dev)
561 {
562 struct sock *sk;
563 struct sockaddr_ll *sll;
564 struct packet_sock *po;
565 u8 *skb_head = skb->data;
566 int skb_len = skb->len;
567 unsigned int snaplen, res;
568
569 if (skb->pkt_type == PACKET_LOOPBACK)
570 goto drop;
571
572 sk = pt->af_packet_priv;
573 po = pkt_sk(sk);
574
575 if (!net_eq(dev_net(dev), sock_net(sk)))
576 goto drop;
577
578 skb->dev = dev;
579
580 if (dev->header_ops) {
581 /* The device has an explicit notion of ll header,
582 * exported to higher levels.
583 *
584 * Otherwise, the device hides details of its frame
585 * structure, so that corresponding packet head is
586 * never delivered to user.
587 */
588 if (sk->sk_type != SOCK_DGRAM)
589 skb_push(skb, skb->data - skb_mac_header(skb));
590 else if (skb->pkt_type == PACKET_OUTGOING) {
591 /* Special case: outgoing packets have ll header at head */
592 skb_pull(skb, skb_network_offset(skb));
593 }
594 }
595
596 snaplen = skb->len;
597
598 res = run_filter(skb, sk, snaplen);
599 if (!res)
600 goto drop_n_restore;
601 if (snaplen > res)
602 snaplen = res;
603
604 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
605 (unsigned)sk->sk_rcvbuf)
606 goto drop_n_acct;
607
608 if (skb_shared(skb)) {
609 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
610 if (nskb == NULL)
611 goto drop_n_acct;
612
613 if (skb_head != skb->data) {
614 skb->data = skb_head;
615 skb->len = skb_len;
616 }
617 kfree_skb(skb);
618 skb = nskb;
619 }
620
621 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
622 sizeof(skb->cb));
623
624 sll = &PACKET_SKB_CB(skb)->sa.ll;
625 sll->sll_family = AF_PACKET;
626 sll->sll_hatype = dev->type;
627 sll->sll_protocol = skb->protocol;
628 sll->sll_pkttype = skb->pkt_type;
629 if (unlikely(po->origdev))
630 sll->sll_ifindex = orig_dev->ifindex;
631 else
632 sll->sll_ifindex = dev->ifindex;
633
634 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
635
636 PACKET_SKB_CB(skb)->origlen = skb->len;
637
638 if (pskb_trim(skb, snaplen))
639 goto drop_n_acct;
640
641 skb_set_owner_r(skb, sk);
642 skb->dev = NULL;
643 skb_dst_drop(skb);
644
645 /* drop conntrack reference */
646 nf_reset(skb);
647
648 spin_lock(&sk->sk_receive_queue.lock);
649 po->stats.tp_packets++;
650 skb->dropcount = atomic_read(&sk->sk_drops);
651 __skb_queue_tail(&sk->sk_receive_queue, skb);
652 spin_unlock(&sk->sk_receive_queue.lock);
653 sk->sk_data_ready(sk, skb->len);
654 return 0;
655
656 drop_n_acct:
657 po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
658
659 drop_n_restore:
660 if (skb_head != skb->data && skb_shared(skb)) {
661 skb->data = skb_head;
662 skb->len = skb_len;
663 }
664 drop:
665 consume_skb(skb);
666 return 0;
667 }
668
669 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
670 struct packet_type *pt, struct net_device *orig_dev)
671 {
672 struct sock *sk;
673 struct packet_sock *po;
674 struct sockaddr_ll *sll;
675 union {
676 struct tpacket_hdr *h1;
677 struct tpacket2_hdr *h2;
678 void *raw;
679 } h;
680 u8 *skb_head = skb->data;
681 int skb_len = skb->len;
682 unsigned int snaplen, res;
683 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
684 unsigned short macoff, netoff, hdrlen;
685 struct sk_buff *copy_skb = NULL;
686 struct timeval tv;
687 struct timespec ts;
688 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
689
690 if (skb->pkt_type == PACKET_LOOPBACK)
691 goto drop;
692
693 sk = pt->af_packet_priv;
694 po = pkt_sk(sk);
695
696 if (!net_eq(dev_net(dev), sock_net(sk)))
697 goto drop;
698
699 if (dev->header_ops) {
700 if (sk->sk_type != SOCK_DGRAM)
701 skb_push(skb, skb->data - skb_mac_header(skb));
702 else if (skb->pkt_type == PACKET_OUTGOING) {
703 /* Special case: outgoing packets have ll header at head */
704 skb_pull(skb, skb_network_offset(skb));
705 }
706 }
707
708 if (skb->ip_summed == CHECKSUM_PARTIAL)
709 status |= TP_STATUS_CSUMNOTREADY;
710
711 snaplen = skb->len;
712
713 res = run_filter(skb, sk, snaplen);
714 if (!res)
715 goto drop_n_restore;
716 if (snaplen > res)
717 snaplen = res;
718
719 if (sk->sk_type == SOCK_DGRAM) {
720 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
721 po->tp_reserve;
722 } else {
723 unsigned maclen = skb_network_offset(skb);
724 netoff = TPACKET_ALIGN(po->tp_hdrlen +
725 (maclen < 16 ? 16 : maclen)) +
726 po->tp_reserve;
727 macoff = netoff - maclen;
728 }
729
730 if (macoff + snaplen > po->rx_ring.frame_size) {
731 if (po->copy_thresh &&
732 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
733 (unsigned)sk->sk_rcvbuf) {
734 if (skb_shared(skb)) {
735 copy_skb = skb_clone(skb, GFP_ATOMIC);
736 } else {
737 copy_skb = skb_get(skb);
738 skb_head = skb->data;
739 }
740 if (copy_skb)
741 skb_set_owner_r(copy_skb, sk);
742 }
743 snaplen = po->rx_ring.frame_size - macoff;
744 if ((int)snaplen < 0)
745 snaplen = 0;
746 }
747
748 spin_lock(&sk->sk_receive_queue.lock);
749 h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
750 if (!h.raw)
751 goto ring_is_full;
752 packet_increment_head(&po->rx_ring);
753 po->stats.tp_packets++;
754 if (copy_skb) {
755 status |= TP_STATUS_COPY;
756 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
757 }
758 if (!po->stats.tp_drops)
759 status &= ~TP_STATUS_LOSING;
760 spin_unlock(&sk->sk_receive_queue.lock);
761
762 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
763
764 switch (po->tp_version) {
765 case TPACKET_V1:
766 h.h1->tp_len = skb->len;
767 h.h1->tp_snaplen = snaplen;
768 h.h1->tp_mac = macoff;
769 h.h1->tp_net = netoff;
770 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
771 && shhwtstamps->syststamp.tv64)
772 tv = ktime_to_timeval(shhwtstamps->syststamp);
773 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
774 && shhwtstamps->hwtstamp.tv64)
775 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
776 else if (skb->tstamp.tv64)
777 tv = ktime_to_timeval(skb->tstamp);
778 else
779 do_gettimeofday(&tv);
780 h.h1->tp_sec = tv.tv_sec;
781 h.h1->tp_usec = tv.tv_usec;
782 hdrlen = sizeof(*h.h1);
783 break;
784 case TPACKET_V2:
785 h.h2->tp_len = skb->len;
786 h.h2->tp_snaplen = snaplen;
787 h.h2->tp_mac = macoff;
788 h.h2->tp_net = netoff;
789 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
790 && shhwtstamps->syststamp.tv64)
791 ts = ktime_to_timespec(shhwtstamps->syststamp);
792 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
793 && shhwtstamps->hwtstamp.tv64)
794 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
795 else if (skb->tstamp.tv64)
796 ts = ktime_to_timespec(skb->tstamp);
797 else
798 getnstimeofday(&ts);
799 h.h2->tp_sec = ts.tv_sec;
800 h.h2->tp_nsec = ts.tv_nsec;
801 if (vlan_tx_tag_present(skb)) {
802 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
803 status |= TP_STATUS_VLAN_VALID;
804 } else {
805 h.h2->tp_vlan_tci = 0;
806 }
807 h.h2->tp_padding = 0;
808 hdrlen = sizeof(*h.h2);
809 break;
810 default:
811 BUG();
812 }
813
814 sll = h.raw + TPACKET_ALIGN(hdrlen);
815 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
816 sll->sll_family = AF_PACKET;
817 sll->sll_hatype = dev->type;
818 sll->sll_protocol = skb->protocol;
819 sll->sll_pkttype = skb->pkt_type;
820 if (unlikely(po->origdev))
821 sll->sll_ifindex = orig_dev->ifindex;
822 else
823 sll->sll_ifindex = dev->ifindex;
824
825 __packet_set_status(po, h.raw, status);
826 smp_mb();
827 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
828 {
829 u8 *start, *end;
830
831 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen);
832 for (start = h.raw; start < end; start += PAGE_SIZE)
833 flush_dcache_page(pgv_to_page(start));
834 }
835 #endif
836
837 sk->sk_data_ready(sk, 0);
838
839 drop_n_restore:
840 if (skb_head != skb->data && skb_shared(skb)) {
841 skb->data = skb_head;
842 skb->len = skb_len;
843 }
844 drop:
845 kfree_skb(skb);
846 return 0;
847
848 ring_is_full:
849 po->stats.tp_drops++;
850 spin_unlock(&sk->sk_receive_queue.lock);
851
852 sk->sk_data_ready(sk, 0);
853 kfree_skb(copy_skb);
854 goto drop_n_restore;
855 }
856
857 static void tpacket_destruct_skb(struct sk_buff *skb)
858 {
859 struct packet_sock *po = pkt_sk(skb->sk);
860 void *ph;
861
862 BUG_ON(skb == NULL);
863
864 if (likely(po->tx_ring.pg_vec)) {
865 ph = skb_shinfo(skb)->destructor_arg;
866 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
867 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
868 atomic_dec(&po->tx_ring.pending);
869 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
870 }
871
872 sock_wfree(skb);
873 }
874
875 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
876 void *frame, struct net_device *dev, int size_max,
877 __be16 proto, unsigned char *addr)
878 {
879 union {
880 struct tpacket_hdr *h1;
881 struct tpacket2_hdr *h2;
882 void *raw;
883 } ph;
884 int to_write, offset, len, tp_len, nr_frags, len_max;
885 struct socket *sock = po->sk.sk_socket;
886 struct page *page;
887 void *data;
888 int err;
889
890 ph.raw = frame;
891
892 skb->protocol = proto;
893 skb->dev = dev;
894 skb->priority = po->sk.sk_priority;
895 skb->mark = po->sk.sk_mark;
896 skb_shinfo(skb)->destructor_arg = ph.raw;
897
898 switch (po->tp_version) {
899 case TPACKET_V2:
900 tp_len = ph.h2->tp_len;
901 break;
902 default:
903 tp_len = ph.h1->tp_len;
904 break;
905 }
906 if (unlikely(tp_len > size_max)) {
907 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
908 return -EMSGSIZE;
909 }
910
911 skb_reserve(skb, LL_RESERVED_SPACE(dev));
912 skb_reset_network_header(skb);
913
914 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
915 to_write = tp_len;
916
917 if (sock->type == SOCK_DGRAM) {
918 err = dev_hard_header(skb, dev, ntohs(proto), addr,
919 NULL, tp_len);
920 if (unlikely(err < 0))
921 return -EINVAL;
922 } else if (dev->hard_header_len) {
923 /* net device doesn't like empty head */
924 if (unlikely(tp_len <= dev->hard_header_len)) {
925 pr_err("packet size is too short (%d < %d)\n",
926 tp_len, dev->hard_header_len);
927 return -EINVAL;
928 }
929
930 skb_push(skb, dev->hard_header_len);
931 err = skb_store_bits(skb, 0, data,
932 dev->hard_header_len);
933 if (unlikely(err))
934 return err;
935
936 data += dev->hard_header_len;
937 to_write -= dev->hard_header_len;
938 }
939
940 err = -EFAULT;
941 offset = offset_in_page(data);
942 len_max = PAGE_SIZE - offset;
943 len = ((to_write > len_max) ? len_max : to_write);
944
945 skb->data_len = to_write;
946 skb->len += to_write;
947 skb->truesize += to_write;
948 atomic_add(to_write, &po->sk.sk_wmem_alloc);
949
950 while (likely(to_write)) {
951 nr_frags = skb_shinfo(skb)->nr_frags;
952
953 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
954 pr_err("Packet exceed the number of skb frags(%lu)\n",
955 MAX_SKB_FRAGS);
956 return -EFAULT;
957 }
958
959 page = pgv_to_page(data);
960 data += len;
961 flush_dcache_page(page);
962 get_page(page);
963 skb_fill_page_desc(skb, nr_frags, page, offset, len);
964 to_write -= len;
965 offset = 0;
966 len_max = PAGE_SIZE;
967 len = ((to_write > len_max) ? len_max : to_write);
968 }
969
970 return tp_len;
971 }
972
973 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
974 {
975 struct sk_buff *skb;
976 struct net_device *dev;
977 __be16 proto;
978 int ifindex, err, reserve = 0;
979 void *ph;
980 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
981 int tp_len, size_max;
982 unsigned char *addr;
983 int len_sum = 0;
984 int status = 0;
985
986 mutex_lock(&po->pg_vec_lock);
987
988 err = -EBUSY;
989 if (saddr == NULL) {
990 ifindex = po->ifindex;
991 proto = po->num;
992 addr = NULL;
993 } else {
994 err = -EINVAL;
995 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
996 goto out;
997 if (msg->msg_namelen < (saddr->sll_halen
998 + offsetof(struct sockaddr_ll,
999 sll_addr)))
1000 goto out;
1001 ifindex = saddr->sll_ifindex;
1002 proto = saddr->sll_protocol;
1003 addr = saddr->sll_addr;
1004 }
1005
1006 dev = dev_get_by_index(sock_net(&po->sk), ifindex);
1007 err = -ENXIO;
1008 if (unlikely(dev == NULL))
1009 goto out;
1010
1011 reserve = dev->hard_header_len;
1012
1013 err = -ENETDOWN;
1014 if (unlikely(!(dev->flags & IFF_UP)))
1015 goto out_put;
1016
1017 size_max = po->tx_ring.frame_size
1018 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
1019
1020 if (size_max > dev->mtu + reserve)
1021 size_max = dev->mtu + reserve;
1022
1023 do {
1024 ph = packet_current_frame(po, &po->tx_ring,
1025 TP_STATUS_SEND_REQUEST);
1026
1027 if (unlikely(ph == NULL)) {
1028 schedule();
1029 continue;
1030 }
1031
1032 status = TP_STATUS_SEND_REQUEST;
1033 skb = sock_alloc_send_skb(&po->sk,
1034 LL_ALLOCATED_SPACE(dev)
1035 + sizeof(struct sockaddr_ll),
1036 0, &err);
1037
1038 if (unlikely(skb == NULL))
1039 goto out_status;
1040
1041 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
1042 addr);
1043
1044 if (unlikely(tp_len < 0)) {
1045 if (po->tp_loss) {
1046 __packet_set_status(po, ph,
1047 TP_STATUS_AVAILABLE);
1048 packet_increment_head(&po->tx_ring);
1049 kfree_skb(skb);
1050 continue;
1051 } else {
1052 status = TP_STATUS_WRONG_FORMAT;
1053 err = tp_len;
1054 goto out_status;
1055 }
1056 }
1057
1058 skb->destructor = tpacket_destruct_skb;
1059 __packet_set_status(po, ph, TP_STATUS_SENDING);
1060 atomic_inc(&po->tx_ring.pending);
1061
1062 status = TP_STATUS_SEND_REQUEST;
1063 err = dev_queue_xmit(skb);
1064 if (unlikely(err > 0)) {
1065 err = net_xmit_errno(err);
1066 if (err && __packet_get_status(po, ph) ==
1067 TP_STATUS_AVAILABLE) {
1068 /* skb was destructed already */
1069 skb = NULL;
1070 goto out_status;
1071 }
1072 /*
1073 * skb was dropped but not destructed yet;
1074 * let's treat it like congestion or err < 0
1075 */
1076 err = 0;
1077 }
1078 packet_increment_head(&po->tx_ring);
1079 len_sum += tp_len;
1080 } while (likely((ph != NULL) ||
1081 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
1082 (atomic_read(&po->tx_ring.pending))))
1083 );
1084
1085 err = len_sum;
1086 goto out_put;
1087
1088 out_status:
1089 __packet_set_status(po, ph, status);
1090 kfree_skb(skb);
1091 out_put:
1092 dev_put(dev);
1093 out:
1094 mutex_unlock(&po->pg_vec_lock);
1095 return err;
1096 }
1097
1098 static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
1099 size_t reserve, size_t len,
1100 size_t linear, int noblock,
1101 int *err)
1102 {
1103 struct sk_buff *skb;
1104
1105 /* Under a page? Don't bother with paged skb. */
1106 if (prepad + len < PAGE_SIZE || !linear)
1107 linear = len;
1108
1109 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
1110 err);
1111 if (!skb)
1112 return NULL;
1113
1114 skb_reserve(skb, reserve);
1115 skb_put(skb, linear);
1116 skb->data_len = len - linear;
1117 skb->len += len - linear;
1118
1119 return skb;
1120 }
1121
1122 static int packet_snd(struct socket *sock,
1123 struct msghdr *msg, size_t len)
1124 {
1125 struct sock *sk = sock->sk;
1126 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
1127 struct sk_buff *skb;
1128 struct net_device *dev;
1129 __be16 proto;
1130 unsigned char *addr;
1131 int ifindex, err, reserve = 0;
1132 struct virtio_net_hdr vnet_hdr = { 0 };
1133 int offset = 0;
1134 int vnet_hdr_len;
1135 struct packet_sock *po = pkt_sk(sk);
1136 unsigned short gso_type = 0;
1137
1138 /*
1139 * Get and verify the address.
1140 */
1141
1142 if (saddr == NULL) {
1143 ifindex = po->ifindex;
1144 proto = po->num;
1145 addr = NULL;
1146 } else {
1147 err = -EINVAL;
1148 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
1149 goto out;
1150 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
1151 goto out;
1152 ifindex = saddr->sll_ifindex;
1153 proto = saddr->sll_protocol;
1154 addr = saddr->sll_addr;
1155 }
1156
1157
1158 dev = dev_get_by_index(sock_net(sk), ifindex);
1159 err = -ENXIO;
1160 if (dev == NULL)
1161 goto out_unlock;
1162 if (sock->type == SOCK_RAW)
1163 reserve = dev->hard_header_len;
1164
1165 err = -ENETDOWN;
1166 if (!(dev->flags & IFF_UP))
1167 goto out_unlock;
1168
1169 if (po->has_vnet_hdr) {
1170 vnet_hdr_len = sizeof(vnet_hdr);
1171
1172 err = -EINVAL;
1173 if (len < vnet_hdr_len)
1174 goto out_unlock;
1175
1176 len -= vnet_hdr_len;
1177
1178 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
1179 vnet_hdr_len);
1180 if (err < 0)
1181 goto out_unlock;
1182
1183 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
1184 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
1185 vnet_hdr.hdr_len))
1186 vnet_hdr.hdr_len = vnet_hdr.csum_start +
1187 vnet_hdr.csum_offset + 2;
1188
1189 err = -EINVAL;
1190 if (vnet_hdr.hdr_len > len)
1191 goto out_unlock;
1192
1193 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
1194 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
1195 case VIRTIO_NET_HDR_GSO_TCPV4:
1196 gso_type = SKB_GSO_TCPV4;
1197 break;
1198 case VIRTIO_NET_HDR_GSO_TCPV6:
1199 gso_type = SKB_GSO_TCPV6;
1200 break;
1201 case VIRTIO_NET_HDR_GSO_UDP:
1202 gso_type = SKB_GSO_UDP;
1203 break;
1204 default:
1205 goto out_unlock;
1206 }
1207
1208 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
1209 gso_type |= SKB_GSO_TCP_ECN;
1210
1211 if (vnet_hdr.gso_size == 0)
1212 goto out_unlock;
1213
1214 }
1215 }
1216
1217 err = -EMSGSIZE;
1218 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
1219 goto out_unlock;
1220
1221 err = -ENOBUFS;
1222 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
1223 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
1224 msg->msg_flags & MSG_DONTWAIT, &err);
1225 if (skb == NULL)
1226 goto out_unlock;
1227
1228 skb_set_network_header(skb, reserve);
1229
1230 err = -EINVAL;
1231 if (sock->type == SOCK_DGRAM &&
1232 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1233 goto out_free;
1234
1235 /* Returns -EFAULT on error */
1236 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
1237 if (err)
1238 goto out_free;
1239 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1240 if (err < 0)
1241 goto out_free;
1242
1243 if (!gso_type && (len > dev->mtu + reserve)) {
1244 /* Earlier code assumed this would be a VLAN pkt,
1245 * double-check this now that we have the actual
1246 * packet in hand.
1247 */
1248 struct ethhdr *ehdr;
1249 skb_reset_mac_header(skb);
1250 ehdr = eth_hdr(skb);
1251 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1252 err = -EMSGSIZE;
1253 goto out_free;
1254 }
1255 }
1256
1257 skb->protocol = proto;
1258 skb->dev = dev;
1259 skb->priority = sk->sk_priority;
1260 skb->mark = sk->sk_mark;
1261
1262 if (po->has_vnet_hdr) {
1263 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1264 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
1265 vnet_hdr.csum_offset)) {
1266 err = -EINVAL;
1267 goto out_free;
1268 }
1269 }
1270
1271 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
1272 skb_shinfo(skb)->gso_type = gso_type;
1273
1274 /* Header must be checked, and gso_segs computed. */
1275 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
1276 skb_shinfo(skb)->gso_segs = 0;
1277
1278 len += vnet_hdr_len;
1279 }
1280
1281 /*
1282 * Now send it
1283 */
1284
1285 err = dev_queue_xmit(skb);
1286 if (err > 0 && (err = net_xmit_errno(err)) != 0)
1287 goto out_unlock;
1288
1289 dev_put(dev);
1290
1291 return len;
1292
1293 out_free:
1294 kfree_skb(skb);
1295 out_unlock:
1296 if (dev)
1297 dev_put(dev);
1298 out:
1299 return err;
1300 }
1301
1302 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
1303 struct msghdr *msg, size_t len)
1304 {
1305 struct sock *sk = sock->sk;
1306 struct packet_sock *po = pkt_sk(sk);
1307 if (po->tx_ring.pg_vec)
1308 return tpacket_snd(po, msg);
1309 else
1310 return packet_snd(sock, msg, len);
1311 }
1312
1313 /*
1314 * Close a PACKET socket. This is fairly simple. We immediately go
1315 * to 'closed' state and remove our protocol entry in the device list.
1316 */
1317
1318 static int packet_release(struct socket *sock)
1319 {
1320 struct sock *sk = sock->sk;
1321 struct packet_sock *po;
1322 struct net *net;
1323 struct tpacket_req req;
1324
1325 if (!sk)
1326 return 0;
1327
1328 net = sock_net(sk);
1329 po = pkt_sk(sk);
1330
1331 spin_lock_bh(&net->packet.sklist_lock);
1332 sk_del_node_init_rcu(sk);
1333 sock_prot_inuse_add(net, sk->sk_prot, -1);
1334 spin_unlock_bh(&net->packet.sklist_lock);
1335
1336 spin_lock(&po->bind_lock);
1337 if (po->running) {
1338 /*
1339 * Remove from protocol table
1340 */
1341 po->running = 0;
1342 po->num = 0;
1343 __dev_remove_pack(&po->prot_hook);
1344 __sock_put(sk);
1345 }
1346 spin_unlock(&po->bind_lock);
1347
1348 packet_flush_mclist(sk);
1349
1350 memset(&req, 0, sizeof(req));
1351
1352 if (po->rx_ring.pg_vec)
1353 packet_set_ring(sk, &req, 1, 0);
1354
1355 if (po->tx_ring.pg_vec)
1356 packet_set_ring(sk, &req, 1, 1);
1357
1358 synchronize_net();
1359 /*
1360 * Now the socket is dead. No more input will appear.
1361 */
1362 sock_orphan(sk);
1363 sock->sk = NULL;
1364
1365 /* Purge queues */
1366
1367 skb_queue_purge(&sk->sk_receive_queue);
1368 sk_refcnt_debug_release(sk);
1369
1370 sock_put(sk);
1371 return 0;
1372 }
1373
1374 /*
1375 * Attach a packet hook.
1376 */
1377
1378 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
1379 {
1380 struct packet_sock *po = pkt_sk(sk);
1381 /*
1382 * Detach an existing hook if present.
1383 */
1384
1385 lock_sock(sk);
1386
1387 spin_lock(&po->bind_lock);
1388 if (po->running) {
1389 __sock_put(sk);
1390 po->running = 0;
1391 po->num = 0;
1392 spin_unlock(&po->bind_lock);
1393 dev_remove_pack(&po->prot_hook);
1394 spin_lock(&po->bind_lock);
1395 }
1396
1397 po->num = protocol;
1398 po->prot_hook.type = protocol;
1399 po->prot_hook.dev = dev;
1400
1401 po->ifindex = dev ? dev->ifindex : 0;
1402
1403 if (protocol == 0)
1404 goto out_unlock;
1405
1406 if (!dev || (dev->flags & IFF_UP)) {
1407 dev_add_pack(&po->prot_hook);
1408 sock_hold(sk);
1409 po->running = 1;
1410 } else {
1411 sk->sk_err = ENETDOWN;
1412 if (!sock_flag(sk, SOCK_DEAD))
1413 sk->sk_error_report(sk);
1414 }
1415
1416 out_unlock:
1417 spin_unlock(&po->bind_lock);
1418 release_sock(sk);
1419 return 0;
1420 }
1421
1422 /*
1423 * Bind a packet socket to a device
1424 */
1425
1426 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
1427 int addr_len)
1428 {
1429 struct sock *sk = sock->sk;
1430 char name[15];
1431 struct net_device *dev;
1432 int err = -ENODEV;
1433
1434 /*
1435 * Check legality
1436 */
1437
1438 if (addr_len != sizeof(struct sockaddr))
1439 return -EINVAL;
1440 strlcpy(name, uaddr->sa_data, sizeof(name));
1441
1442 dev = dev_get_by_name(sock_net(sk), name);
1443 if (dev) {
1444 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
1445 dev_put(dev);
1446 }
1447 return err;
1448 }
1449
1450 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1451 {
1452 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
1453 struct sock *sk = sock->sk;
1454 struct net_device *dev = NULL;
1455 int err;
1456
1457
1458 /*
1459 * Check legality
1460 */
1461
1462 if (addr_len < sizeof(struct sockaddr_ll))
1463 return -EINVAL;
1464 if (sll->sll_family != AF_PACKET)
1465 return -EINVAL;
1466
1467 if (sll->sll_ifindex) {
1468 err = -ENODEV;
1469 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1470 if (dev == NULL)
1471 goto out;
1472 }
1473 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1474 if (dev)
1475 dev_put(dev);
1476
1477 out:
1478 return err;
1479 }
1480
1481 static struct proto packet_proto = {
1482 .name = "PACKET",
1483 .owner = THIS_MODULE,
1484 .obj_size = sizeof(struct packet_sock),
1485 };
1486
1487 /*
1488 * Create a packet of type SOCK_PACKET.
1489 */
1490
1491 static int packet_create(struct net *net, struct socket *sock, int protocol,
1492 int kern)
1493 {
1494 struct sock *sk;
1495 struct packet_sock *po;
1496 __be16 proto = (__force __be16)protocol; /* weird, but documented */
1497 int err;
1498
1499 if (!capable(CAP_NET_RAW))
1500 return -EPERM;
1501 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1502 sock->type != SOCK_PACKET)
1503 return -ESOCKTNOSUPPORT;
1504
1505 sock->state = SS_UNCONNECTED;
1506
1507 err = -ENOBUFS;
1508 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1509 if (sk == NULL)
1510 goto out;
1511
1512 sock->ops = &packet_ops;
1513 if (sock->type == SOCK_PACKET)
1514 sock->ops = &packet_ops_spkt;
1515
1516 sock_init_data(sock, sk);
1517
1518 po = pkt_sk(sk);
1519 sk->sk_family = PF_PACKET;
1520 po->num = proto;
1521
1522 sk->sk_destruct = packet_sock_destruct;
1523 sk_refcnt_debug_inc(sk);
1524
1525 /*
1526 * Attach a protocol block
1527 */
1528
1529 spin_lock_init(&po->bind_lock);
1530 mutex_init(&po->pg_vec_lock);
1531 po->prot_hook.func = packet_rcv;
1532
1533 if (sock->type == SOCK_PACKET)
1534 po->prot_hook.func = packet_rcv_spkt;
1535
1536 po->prot_hook.af_packet_priv = sk;
1537
1538 if (proto) {
1539 po->prot_hook.type = proto;
1540 dev_add_pack(&po->prot_hook);
1541 sock_hold(sk);
1542 po->running = 1;
1543 }
1544
1545 spin_lock_bh(&net->packet.sklist_lock);
1546 sk_add_node_rcu(sk, &net->packet.sklist);
1547 sock_prot_inuse_add(net, &packet_proto, 1);
1548 spin_unlock_bh(&net->packet.sklist_lock);
1549
1550 return 0;
1551 out:
1552 return err;
1553 }
1554
1555 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
1556 {
1557 struct sock_exterr_skb *serr;
1558 struct sk_buff *skb, *skb2;
1559 int copied, err;
1560
1561 err = -EAGAIN;
1562 skb = skb_dequeue(&sk->sk_error_queue);
1563 if (skb == NULL)
1564 goto out;
1565
1566 copied = skb->len;
1567 if (copied > len) {
1568 msg->msg_flags |= MSG_TRUNC;
1569 copied = len;
1570 }
1571 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1572 if (err)
1573 goto out_free_skb;
1574
1575 sock_recv_timestamp(msg, sk, skb);
1576
1577 serr = SKB_EXT_ERR(skb);
1578 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
1579 sizeof(serr->ee), &serr->ee);
1580
1581 msg->msg_flags |= MSG_ERRQUEUE;
1582 err = copied;
1583
1584 /* Reset and regenerate socket error */
1585 spin_lock_bh(&sk->sk_error_queue.lock);
1586 sk->sk_err = 0;
1587 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
1588 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
1589 spin_unlock_bh(&sk->sk_error_queue.lock);
1590 sk->sk_error_report(sk);
1591 } else
1592 spin_unlock_bh(&sk->sk_error_queue.lock);
1593
1594 out_free_skb:
1595 kfree_skb(skb);
1596 out:
1597 return err;
1598 }
1599
1600 /*
1601 * Pull a packet from our receive queue and hand it to the user.
1602 * If necessary we block.
1603 */
1604
1605 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1606 struct msghdr *msg, size_t len, int flags)
1607 {
1608 struct sock *sk = sock->sk;
1609 struct sk_buff *skb;
1610 int copied, err;
1611 struct sockaddr_ll *sll;
1612 int vnet_hdr_len = 0;
1613
1614 err = -EINVAL;
1615 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
1616 goto out;
1617
1618 #if 0
1619 /* What error should we return now? EUNATTACH? */
1620 if (pkt_sk(sk)->ifindex < 0)
1621 return -ENODEV;
1622 #endif
1623
1624 if (flags & MSG_ERRQUEUE) {
1625 err = packet_recv_error(sk, msg, len);
1626 goto out;
1627 }
1628
1629 /*
1630 * Call the generic datagram receiver. This handles all sorts
1631 * of horrible races and re-entrancy so we can forget about it
1632 * in the protocol layers.
1633 *
1634 * Now it will return ENETDOWN, if device have just gone down,
1635 * but then it will block.
1636 */
1637
1638 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
1639
1640 /*
1641 * An error occurred so return it. Because skb_recv_datagram()
1642 * handles the blocking we don't see and worry about blocking
1643 * retries.
1644 */
1645
1646 if (skb == NULL)
1647 goto out;
1648
1649 if (pkt_sk(sk)->has_vnet_hdr) {
1650 struct virtio_net_hdr vnet_hdr = { 0 };
1651
1652 err = -EINVAL;
1653 vnet_hdr_len = sizeof(vnet_hdr);
1654 if (len < vnet_hdr_len)
1655 goto out_free;
1656
1657 len -= vnet_hdr_len;
1658
1659 if (skb_is_gso(skb)) {
1660 struct skb_shared_info *sinfo = skb_shinfo(skb);
1661
1662 /* This is a hint as to how much should be linear. */
1663 vnet_hdr.hdr_len = skb_headlen(skb);
1664 vnet_hdr.gso_size = sinfo->gso_size;
1665 if (sinfo->gso_type & SKB_GSO_TCPV4)
1666 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1667 else if (sinfo->gso_type & SKB_GSO_TCPV6)
1668 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1669 else if (sinfo->gso_type & SKB_GSO_UDP)
1670 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
1671 else if (sinfo->gso_type & SKB_GSO_FCOE)
1672 goto out_free;
1673 else
1674 BUG();
1675 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1676 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1677 } else
1678 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
1679
1680 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1681 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1682 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
1683 vnet_hdr.csum_offset = skb->csum_offset;
1684 } /* else everything is zero */
1685
1686 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
1687 vnet_hdr_len);
1688 if (err < 0)
1689 goto out_free;
1690 }
1691
1692 /*
1693 * If the address length field is there to be filled in, we fill
1694 * it in now.
1695 */
1696
1697 sll = &PACKET_SKB_CB(skb)->sa.ll;
1698 if (sock->type == SOCK_PACKET)
1699 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1700 else
1701 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1702
1703 /*
1704 * You lose any data beyond the buffer you gave. If it worries a
1705 * user program they can ask the device for its MTU anyway.
1706 */
1707
1708 copied = skb->len;
1709 if (copied > len) {
1710 copied = len;
1711 msg->msg_flags |= MSG_TRUNC;
1712 }
1713
1714 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1715 if (err)
1716 goto out_free;
1717
1718 sock_recv_ts_and_drops(msg, sk, skb);
1719
1720 if (msg->msg_name)
1721 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1722 msg->msg_namelen);
1723
1724 if (pkt_sk(sk)->auxdata) {
1725 struct tpacket_auxdata aux;
1726
1727 aux.tp_status = TP_STATUS_USER;
1728 if (skb->ip_summed == CHECKSUM_PARTIAL)
1729 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1730 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1731 aux.tp_snaplen = skb->len;
1732 aux.tp_mac = 0;
1733 aux.tp_net = skb_network_offset(skb);
1734 if (vlan_tx_tag_present(skb)) {
1735 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
1736 aux.tp_status |= TP_STATUS_VLAN_VALID;
1737 } else {
1738 aux.tp_vlan_tci = 0;
1739 }
1740 aux.tp_padding = 0;
1741 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1742 }
1743
1744 /*
1745 * Free or return the buffer as appropriate. Again this
1746 * hides all the races and re-entrancy issues from us.
1747 */
1748 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
1749
1750 out_free:
1751 skb_free_datagram(sk, skb);
1752 out:
1753 return err;
1754 }
1755
1756 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1757 int *uaddr_len, int peer)
1758 {
1759 struct net_device *dev;
1760 struct sock *sk = sock->sk;
1761
1762 if (peer)
1763 return -EOPNOTSUPP;
1764
1765 uaddr->sa_family = AF_PACKET;
1766 rcu_read_lock();
1767 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
1768 if (dev)
1769 strncpy(uaddr->sa_data, dev->name, 14);
1770 else
1771 memset(uaddr->sa_data, 0, 14);
1772 rcu_read_unlock();
1773 *uaddr_len = sizeof(*uaddr);
1774
1775 return 0;
1776 }
1777
1778 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1779 int *uaddr_len, int peer)
1780 {
1781 struct net_device *dev;
1782 struct sock *sk = sock->sk;
1783 struct packet_sock *po = pkt_sk(sk);
1784 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
1785
1786 if (peer)
1787 return -EOPNOTSUPP;
1788
1789 sll->sll_family = AF_PACKET;
1790 sll->sll_ifindex = po->ifindex;
1791 sll->sll_protocol = po->num;
1792 sll->sll_pkttype = 0;
1793 rcu_read_lock();
1794 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
1795 if (dev) {
1796 sll->sll_hatype = dev->type;
1797 sll->sll_halen = dev->addr_len;
1798 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1799 } else {
1800 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
1801 sll->sll_halen = 0;
1802 }
1803 rcu_read_unlock();
1804 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1805
1806 return 0;
1807 }
1808
1809 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
1810 int what)
1811 {
1812 switch (i->type) {
1813 case PACKET_MR_MULTICAST:
1814 if (i->alen != dev->addr_len)
1815 return -EINVAL;
1816 if (what > 0)
1817 return dev_mc_add(dev, i->addr);
1818 else
1819 return dev_mc_del(dev, i->addr);
1820 break;
1821 case PACKET_MR_PROMISC:
1822 return dev_set_promiscuity(dev, what);
1823 break;
1824 case PACKET_MR_ALLMULTI:
1825 return dev_set_allmulti(dev, what);
1826 break;
1827 case PACKET_MR_UNICAST:
1828 if (i->alen != dev->addr_len)
1829 return -EINVAL;
1830 if (what > 0)
1831 return dev_uc_add(dev, i->addr);
1832 else
1833 return dev_uc_del(dev, i->addr);
1834 break;
1835 default:
1836 break;
1837 }
1838 return 0;
1839 }
1840
1841 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1842 {
1843 for ( ; i; i = i->next) {
1844 if (i->ifindex == dev->ifindex)
1845 packet_dev_mc(dev, i, what);
1846 }
1847 }
1848
1849 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1850 {
1851 struct packet_sock *po = pkt_sk(sk);
1852 struct packet_mclist *ml, *i;
1853 struct net_device *dev;
1854 int err;
1855
1856 rtnl_lock();
1857
1858 err = -ENODEV;
1859 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
1860 if (!dev)
1861 goto done;
1862
1863 err = -EINVAL;
1864 if (mreq->mr_alen > dev->addr_len)
1865 goto done;
1866
1867 err = -ENOBUFS;
1868 i = kmalloc(sizeof(*i), GFP_KERNEL);
1869 if (i == NULL)
1870 goto done;
1871
1872 err = 0;
1873 for (ml = po->mclist; ml; ml = ml->next) {
1874 if (ml->ifindex == mreq->mr_ifindex &&
1875 ml->type == mreq->mr_type &&
1876 ml->alen == mreq->mr_alen &&
1877 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1878 ml->count++;
1879 /* Free the new element ... */
1880 kfree(i);
1881 goto done;
1882 }
1883 }
1884
1885 i->type = mreq->mr_type;
1886 i->ifindex = mreq->mr_ifindex;
1887 i->alen = mreq->mr_alen;
1888 memcpy(i->addr, mreq->mr_address, i->alen);
1889 i->count = 1;
1890 i->next = po->mclist;
1891 po->mclist = i;
1892 err = packet_dev_mc(dev, i, 1);
1893 if (err) {
1894 po->mclist = i->next;
1895 kfree(i);
1896 }
1897
1898 done:
1899 rtnl_unlock();
1900 return err;
1901 }
1902
1903 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1904 {
1905 struct packet_mclist *ml, **mlp;
1906
1907 rtnl_lock();
1908
1909 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1910 if (ml->ifindex == mreq->mr_ifindex &&
1911 ml->type == mreq->mr_type &&
1912 ml->alen == mreq->mr_alen &&
1913 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1914 if (--ml->count == 0) {
1915 struct net_device *dev;
1916 *mlp = ml->next;
1917 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1918 if (dev)
1919 packet_dev_mc(dev, ml, -1);
1920 kfree(ml);
1921 }
1922 rtnl_unlock();
1923 return 0;
1924 }
1925 }
1926 rtnl_unlock();
1927 return -EADDRNOTAVAIL;
1928 }
1929
1930 static void packet_flush_mclist(struct sock *sk)
1931 {
1932 struct packet_sock *po = pkt_sk(sk);
1933 struct packet_mclist *ml;
1934
1935 if (!po->mclist)
1936 return;
1937
1938 rtnl_lock();
1939 while ((ml = po->mclist) != NULL) {
1940 struct net_device *dev;
1941
1942 po->mclist = ml->next;
1943 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1944 if (dev != NULL)
1945 packet_dev_mc(dev, ml, -1);
1946 kfree(ml);
1947 }
1948 rtnl_unlock();
1949 }
1950
1951 static int
1952 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
1953 {
1954 struct sock *sk = sock->sk;
1955 struct packet_sock *po = pkt_sk(sk);
1956 int ret;
1957
1958 if (level != SOL_PACKET)
1959 return -ENOPROTOOPT;
1960
1961 switch (optname) {
1962 case PACKET_ADD_MEMBERSHIP:
1963 case PACKET_DROP_MEMBERSHIP:
1964 {
1965 struct packet_mreq_max mreq;
1966 int len = optlen;
1967 memset(&mreq, 0, sizeof(mreq));
1968 if (len < sizeof(struct packet_mreq))
1969 return -EINVAL;
1970 if (len > sizeof(mreq))
1971 len = sizeof(mreq);
1972 if (copy_from_user(&mreq, optval, len))
1973 return -EFAULT;
1974 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1975 return -EINVAL;
1976 if (optname == PACKET_ADD_MEMBERSHIP)
1977 ret = packet_mc_add(sk, &mreq);
1978 else
1979 ret = packet_mc_drop(sk, &mreq);
1980 return ret;
1981 }
1982
1983 case PACKET_RX_RING:
1984 case PACKET_TX_RING:
1985 {
1986 struct tpacket_req req;
1987
1988 if (optlen < sizeof(req))
1989 return -EINVAL;
1990 if (pkt_sk(sk)->has_vnet_hdr)
1991 return -EINVAL;
1992 if (copy_from_user(&req, optval, sizeof(req)))
1993 return -EFAULT;
1994 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
1995 }
1996 case PACKET_COPY_THRESH:
1997 {
1998 int val;
1999
2000 if (optlen != sizeof(val))
2001 return -EINVAL;
2002 if (copy_from_user(&val, optval, sizeof(val)))
2003 return -EFAULT;
2004
2005 pkt_sk(sk)->copy_thresh = val;
2006 return 0;
2007 }
2008 case PACKET_VERSION:
2009 {
2010 int val;
2011
2012 if (optlen != sizeof(val))
2013 return -EINVAL;
2014 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2015 return -EBUSY;
2016 if (copy_from_user(&val, optval, sizeof(val)))
2017 return -EFAULT;
2018 switch (val) {
2019 case TPACKET_V1:
2020 case TPACKET_V2:
2021 po->tp_version = val;
2022 return 0;
2023 default:
2024 return -EINVAL;
2025 }
2026 }
2027 case PACKET_RESERVE:
2028 {
2029 unsigned int val;
2030
2031 if (optlen != sizeof(val))
2032 return -EINVAL;
2033 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2034 return -EBUSY;
2035 if (copy_from_user(&val, optval, sizeof(val)))
2036 return -EFAULT;
2037 po->tp_reserve = val;
2038 return 0;
2039 }
2040 case PACKET_LOSS:
2041 {
2042 unsigned int val;
2043
2044 if (optlen != sizeof(val))
2045 return -EINVAL;
2046 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2047 return -EBUSY;
2048 if (copy_from_user(&val, optval, sizeof(val)))
2049 return -EFAULT;
2050 po->tp_loss = !!val;
2051 return 0;
2052 }
2053 case PACKET_AUXDATA:
2054 {
2055 int val;
2056
2057 if (optlen < sizeof(val))
2058 return -EINVAL;
2059 if (copy_from_user(&val, optval, sizeof(val)))
2060 return -EFAULT;
2061
2062 po->auxdata = !!val;
2063 return 0;
2064 }
2065 case PACKET_ORIGDEV:
2066 {
2067 int val;
2068
2069 if (optlen < sizeof(val))
2070 return -EINVAL;
2071 if (copy_from_user(&val, optval, sizeof(val)))
2072 return -EFAULT;
2073
2074 po->origdev = !!val;
2075 return 0;
2076 }
2077 case PACKET_VNET_HDR:
2078 {
2079 int val;
2080
2081 if (sock->type != SOCK_RAW)
2082 return -EINVAL;
2083 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2084 return -EBUSY;
2085 if (optlen < sizeof(val))
2086 return -EINVAL;
2087 if (copy_from_user(&val, optval, sizeof(val)))
2088 return -EFAULT;
2089
2090 po->has_vnet_hdr = !!val;
2091 return 0;
2092 }
2093 case PACKET_TIMESTAMP:
2094 {
2095 int val;
2096
2097 if (optlen != sizeof(val))
2098 return -EINVAL;
2099 if (copy_from_user(&val, optval, sizeof(val)))
2100 return -EFAULT;
2101
2102 po->tp_tstamp = val;
2103 return 0;
2104 }
2105 default:
2106 return -ENOPROTOOPT;
2107 }
2108 }
2109
2110 static int packet_getsockopt(struct socket *sock, int level, int optname,
2111 char __user *optval, int __user *optlen)
2112 {
2113 int len;
2114 int val;
2115 struct sock *sk = sock->sk;
2116 struct packet_sock *po = pkt_sk(sk);
2117 void *data;
2118 struct tpacket_stats st;
2119
2120 if (level != SOL_PACKET)
2121 return -ENOPROTOOPT;
2122
2123 if (get_user(len, optlen))
2124 return -EFAULT;
2125
2126 if (len < 0)
2127 return -EINVAL;
2128
2129 switch (optname) {
2130 case PACKET_STATISTICS:
2131 if (len > sizeof(struct tpacket_stats))
2132 len = sizeof(struct tpacket_stats);
2133 spin_lock_bh(&sk->sk_receive_queue.lock);
2134 st = po->stats;
2135 memset(&po->stats, 0, sizeof(st));
2136 spin_unlock_bh(&sk->sk_receive_queue.lock);
2137 st.tp_packets += st.tp_drops;
2138
2139 data = &st;
2140 break;
2141 case PACKET_AUXDATA:
2142 if (len > sizeof(int))
2143 len = sizeof(int);
2144 val = po->auxdata;
2145
2146 data = &val;
2147 break;
2148 case PACKET_ORIGDEV:
2149 if (len > sizeof(int))
2150 len = sizeof(int);
2151 val = po->origdev;
2152
2153 data = &val;
2154 break;
2155 case PACKET_VNET_HDR:
2156 if (len > sizeof(int))
2157 len = sizeof(int);
2158 val = po->has_vnet_hdr;
2159
2160 data = &val;
2161 break;
2162 case PACKET_VERSION:
2163 if (len > sizeof(int))
2164 len = sizeof(int);
2165 val = po->tp_version;
2166 data = &val;
2167 break;
2168 case PACKET_HDRLEN:
2169 if (len > sizeof(int))
2170 len = sizeof(int);
2171 if (copy_from_user(&val, optval, len))
2172 return -EFAULT;
2173 switch (val) {
2174 case TPACKET_V1:
2175 val = sizeof(struct tpacket_hdr);
2176 break;
2177 case TPACKET_V2:
2178 val = sizeof(struct tpacket2_hdr);
2179 break;
2180 default:
2181 return -EINVAL;
2182 }
2183 data = &val;
2184 break;
2185 case PACKET_RESERVE:
2186 if (len > sizeof(unsigned int))
2187 len = sizeof(unsigned int);
2188 val = po->tp_reserve;
2189 data = &val;
2190 break;
2191 case PACKET_LOSS:
2192 if (len > sizeof(unsigned int))
2193 len = sizeof(unsigned int);
2194 val = po->tp_loss;
2195 data = &val;
2196 break;
2197 case PACKET_TIMESTAMP:
2198 if (len > sizeof(int))
2199 len = sizeof(int);
2200 val = po->tp_tstamp;
2201 data = &val;
2202 break;
2203 default:
2204 return -ENOPROTOOPT;
2205 }
2206
2207 if (put_user(len, optlen))
2208 return -EFAULT;
2209 if (copy_to_user(optval, data, len))
2210 return -EFAULT;
2211 return 0;
2212 }
2213
2214
2215 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
2216 {
2217 struct sock *sk;
2218 struct hlist_node *node;
2219 struct net_device *dev = data;
2220 struct net *net = dev_net(dev);
2221
2222 rcu_read_lock();
2223 sk_for_each_rcu(sk, node, &net->packet.sklist) {
2224 struct packet_sock *po = pkt_sk(sk);
2225
2226 switch (msg) {
2227 case NETDEV_UNREGISTER:
2228 if (po->mclist)
2229 packet_dev_mclist(dev, po->mclist, -1);
2230 /* fallthrough */
2231
2232 case NETDEV_DOWN:
2233 if (dev->ifindex == po->ifindex) {
2234 spin_lock(&po->bind_lock);
2235 if (po->running) {
2236 __dev_remove_pack(&po->prot_hook);
2237 __sock_put(sk);
2238 po->running = 0;
2239 sk->sk_err = ENETDOWN;
2240 if (!sock_flag(sk, SOCK_DEAD))
2241 sk->sk_error_report(sk);
2242 }
2243 if (msg == NETDEV_UNREGISTER) {
2244 po->ifindex = -1;
2245 po->prot_hook.dev = NULL;
2246 }
2247 spin_unlock(&po->bind_lock);
2248 }
2249 break;
2250 case NETDEV_UP:
2251 if (dev->ifindex == po->ifindex) {
2252 spin_lock(&po->bind_lock);
2253 if (po->num && !po->running) {
2254 dev_add_pack(&po->prot_hook);
2255 sock_hold(sk);
2256 po->running = 1;
2257 }
2258 spin_unlock(&po->bind_lock);
2259 }
2260 break;
2261 }
2262 }
2263 rcu_read_unlock();
2264 return NOTIFY_DONE;
2265 }
2266
2267
2268 static int packet_ioctl(struct socket *sock, unsigned int cmd,
2269 unsigned long arg)
2270 {
2271 struct sock *sk = sock->sk;
2272
2273 switch (cmd) {
2274 case SIOCOUTQ:
2275 {
2276 int amount = sk_wmem_alloc_get(sk);
2277
2278 return put_user(amount, (int __user *)arg);
2279 }
2280 case SIOCINQ:
2281 {
2282 struct sk_buff *skb;
2283 int amount = 0;
2284
2285 spin_lock_bh(&sk->sk_receive_queue.lock);
2286 skb = skb_peek(&sk->sk_receive_queue);
2287 if (skb)
2288 amount = skb->len;
2289 spin_unlock_bh(&sk->sk_receive_queue.lock);
2290 return put_user(amount, (int __user *)arg);
2291 }
2292 case SIOCGSTAMP:
2293 return sock_get_timestamp(sk, (struct timeval __user *)arg);
2294 case SIOCGSTAMPNS:
2295 return sock_get_timestampns(sk, (struct timespec __user *)arg);
2296
2297 #ifdef CONFIG_INET
2298 case SIOCADDRT:
2299 case SIOCDELRT:
2300 case SIOCDARP:
2301 case SIOCGARP:
2302 case SIOCSARP:
2303 case SIOCGIFADDR:
2304 case SIOCSIFADDR:
2305 case SIOCGIFBRDADDR:
2306 case SIOCSIFBRDADDR:
2307 case SIOCGIFNETMASK:
2308 case SIOCSIFNETMASK:
2309 case SIOCGIFDSTADDR:
2310 case SIOCSIFDSTADDR:
2311 case SIOCSIFFLAGS:
2312 return inet_dgram_ops.ioctl(sock, cmd, arg);
2313 #endif
2314
2315 default:
2316 return -ENOIOCTLCMD;
2317 }
2318 return 0;
2319 }
2320
2321 static unsigned int packet_poll(struct file *file, struct socket *sock,
2322 poll_table *wait)
2323 {
2324 struct sock *sk = sock->sk;
2325 struct packet_sock *po = pkt_sk(sk);
2326 unsigned int mask = datagram_poll(file, sock, wait);
2327
2328 spin_lock_bh(&sk->sk_receive_queue.lock);
2329 if (po->rx_ring.pg_vec) {
2330 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
2331 mask |= POLLIN | POLLRDNORM;
2332 }
2333 spin_unlock_bh(&sk->sk_receive_queue.lock);
2334 spin_lock_bh(&sk->sk_write_queue.lock);
2335 if (po->tx_ring.pg_vec) {
2336 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
2337 mask |= POLLOUT | POLLWRNORM;
2338 }
2339 spin_unlock_bh(&sk->sk_write_queue.lock);
2340 return mask;
2341 }
2342
2343
2344 /* Dirty? Well, I still did not learn better way to account
2345 * for user mmaps.
2346 */
2347
2348 static void packet_mm_open(struct vm_area_struct *vma)
2349 {
2350 struct file *file = vma->vm_file;
2351 struct socket *sock = file->private_data;
2352 struct sock *sk = sock->sk;
2353
2354 if (sk)
2355 atomic_inc(&pkt_sk(sk)->mapped);
2356 }
2357
2358 static void packet_mm_close(struct vm_area_struct *vma)
2359 {
2360 struct file *file = vma->vm_file;
2361 struct socket *sock = file->private_data;
2362 struct sock *sk = sock->sk;
2363
2364 if (sk)
2365 atomic_dec(&pkt_sk(sk)->mapped);
2366 }
2367
2368 static const struct vm_operations_struct packet_mmap_ops = {
2369 .open = packet_mm_open,
2370 .close = packet_mm_close,
2371 };
2372
2373 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
2374 unsigned int len)
2375 {
2376 int i;
2377
2378 for (i = 0; i < len; i++) {
2379 if (likely(pg_vec[i].buffer)) {
2380 if (is_vmalloc_addr(pg_vec[i].buffer))
2381 vfree(pg_vec[i].buffer);
2382 else
2383 free_pages((unsigned long)pg_vec[i].buffer,
2384 order);
2385 pg_vec[i].buffer = NULL;
2386 }
2387 }
2388 kfree(pg_vec);
2389 }
2390
2391 static inline char *alloc_one_pg_vec_page(unsigned long order)
2392 {
2393 char *buffer = NULL;
2394 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
2395 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
2396
2397 buffer = (char *) __get_free_pages(gfp_flags, order);
2398
2399 if (buffer)
2400 return buffer;
2401
2402 /*
2403 * __get_free_pages failed, fall back to vmalloc
2404 */
2405 buffer = vzalloc((1 << order) * PAGE_SIZE);
2406
2407 if (buffer)
2408 return buffer;
2409
2410 /*
2411 * vmalloc failed, lets dig into swap here
2412 */
2413 gfp_flags &= ~__GFP_NORETRY;
2414 buffer = (char *)__get_free_pages(gfp_flags, order);
2415 if (buffer)
2416 return buffer;
2417
2418 /*
2419 * complete and utter failure
2420 */
2421 return NULL;
2422 }
2423
2424 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2425 {
2426 unsigned int block_nr = req->tp_block_nr;
2427 struct pgv *pg_vec;
2428 int i;
2429
2430 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2431 if (unlikely(!pg_vec))
2432 goto out;
2433
2434 for (i = 0; i < block_nr; i++) {
2435 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2436 if (unlikely(!pg_vec[i].buffer))
2437 goto out_free_pgvec;
2438 }
2439
2440 out:
2441 return pg_vec;
2442
2443 out_free_pgvec:
2444 free_pg_vec(pg_vec, order, block_nr);
2445 pg_vec = NULL;
2446 goto out;
2447 }
2448
2449 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
2450 int closing, int tx_ring)
2451 {
2452 struct pgv *pg_vec = NULL;
2453 struct packet_sock *po = pkt_sk(sk);
2454 int was_running, order = 0;
2455 struct packet_ring_buffer *rb;
2456 struct sk_buff_head *rb_queue;
2457 __be16 num;
2458 int err;
2459
2460 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
2461 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
2462
2463 err = -EBUSY;
2464 if (!closing) {
2465 if (atomic_read(&po->mapped))
2466 goto out;
2467 if (atomic_read(&rb->pending))
2468 goto out;
2469 }
2470
2471 if (req->tp_block_nr) {
2472 /* Sanity tests and some calculations */
2473 err = -EBUSY;
2474 if (unlikely(rb->pg_vec))
2475 goto out;
2476
2477 switch (po->tp_version) {
2478 case TPACKET_V1:
2479 po->tp_hdrlen = TPACKET_HDRLEN;
2480 break;
2481 case TPACKET_V2:
2482 po->tp_hdrlen = TPACKET2_HDRLEN;
2483 break;
2484 }
2485
2486 err = -EINVAL;
2487 if (unlikely((int)req->tp_block_size <= 0))
2488 goto out;
2489 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
2490 goto out;
2491 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
2492 po->tp_reserve))
2493 goto out;
2494 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
2495 goto out;
2496
2497 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
2498 if (unlikely(rb->frames_per_block <= 0))
2499 goto out;
2500 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
2501 req->tp_frame_nr))
2502 goto out;
2503
2504 err = -ENOMEM;
2505 order = get_order(req->tp_block_size);
2506 pg_vec = alloc_pg_vec(req, order);
2507 if (unlikely(!pg_vec))
2508 goto out;
2509 }
2510 /* Done */
2511 else {
2512 err = -EINVAL;
2513 if (unlikely(req->tp_frame_nr))
2514 goto out;
2515 }
2516
2517 lock_sock(sk);
2518
2519 /* Detach socket from network */
2520 spin_lock(&po->bind_lock);
2521 was_running = po->running;
2522 num = po->num;
2523 if (was_running) {
2524 __dev_remove_pack(&po->prot_hook);
2525 po->num = 0;
2526 po->running = 0;
2527 __sock_put(sk);
2528 }
2529 spin_unlock(&po->bind_lock);
2530
2531 synchronize_net();
2532
2533 err = -EBUSY;
2534 mutex_lock(&po->pg_vec_lock);
2535 if (closing || atomic_read(&po->mapped) == 0) {
2536 err = 0;
2537 spin_lock_bh(&rb_queue->lock);
2538 swap(rb->pg_vec, pg_vec);
2539 rb->frame_max = (req->tp_frame_nr - 1);
2540 rb->head = 0;
2541 rb->frame_size = req->tp_frame_size;
2542 spin_unlock_bh(&rb_queue->lock);
2543
2544 swap(rb->pg_vec_order, order);
2545 swap(rb->pg_vec_len, req->tp_block_nr);
2546
2547 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
2548 po->prot_hook.func = (po->rx_ring.pg_vec) ?
2549 tpacket_rcv : packet_rcv;
2550 skb_queue_purge(rb_queue);
2551 if (atomic_read(&po->mapped))
2552 pr_err("packet_mmap: vma is busy: %d\n",
2553 atomic_read(&po->mapped));
2554 }
2555 mutex_unlock(&po->pg_vec_lock);
2556
2557 spin_lock(&po->bind_lock);
2558 if (was_running && !po->running) {
2559 sock_hold(sk);
2560 po->running = 1;
2561 po->num = num;
2562 dev_add_pack(&po->prot_hook);
2563 }
2564 spin_unlock(&po->bind_lock);
2565
2566 release_sock(sk);
2567
2568 if (pg_vec)
2569 free_pg_vec(pg_vec, order, req->tp_block_nr);
2570 out:
2571 return err;
2572 }
2573
2574 static int packet_mmap(struct file *file, struct socket *sock,
2575 struct vm_area_struct *vma)
2576 {
2577 struct sock *sk = sock->sk;
2578 struct packet_sock *po = pkt_sk(sk);
2579 unsigned long size, expected_size;
2580 struct packet_ring_buffer *rb;
2581 unsigned long start;
2582 int err = -EINVAL;
2583 int i;
2584
2585 if (vma->vm_pgoff)
2586 return -EINVAL;
2587
2588 mutex_lock(&po->pg_vec_lock);
2589
2590 expected_size = 0;
2591 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2592 if (rb->pg_vec) {
2593 expected_size += rb->pg_vec_len
2594 * rb->pg_vec_pages
2595 * PAGE_SIZE;
2596 }
2597 }
2598
2599 if (expected_size == 0)
2600 goto out;
2601
2602 size = vma->vm_end - vma->vm_start;
2603 if (size != expected_size)
2604 goto out;
2605
2606 start = vma->vm_start;
2607 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2608 if (rb->pg_vec == NULL)
2609 continue;
2610
2611 for (i = 0; i < rb->pg_vec_len; i++) {
2612 struct page *page;
2613 void *kaddr = rb->pg_vec[i].buffer;
2614 int pg_num;
2615
2616 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
2617 page = pgv_to_page(kaddr);
2618 err = vm_insert_page(vma, start, page);
2619 if (unlikely(err))
2620 goto out;
2621 start += PAGE_SIZE;
2622 kaddr += PAGE_SIZE;
2623 }
2624 }
2625 }
2626
2627 atomic_inc(&po->mapped);
2628 vma->vm_ops = &packet_mmap_ops;
2629 err = 0;
2630
2631 out:
2632 mutex_unlock(&po->pg_vec_lock);
2633 return err;
2634 }
2635
2636 static const struct proto_ops packet_ops_spkt = {
2637 .family = PF_PACKET,
2638 .owner = THIS_MODULE,
2639 .release = packet_release,
2640 .bind = packet_bind_spkt,
2641 .connect = sock_no_connect,
2642 .socketpair = sock_no_socketpair,
2643 .accept = sock_no_accept,
2644 .getname = packet_getname_spkt,
2645 .poll = datagram_poll,
2646 .ioctl = packet_ioctl,
2647 .listen = sock_no_listen,
2648 .shutdown = sock_no_shutdown,
2649 .setsockopt = sock_no_setsockopt,
2650 .getsockopt = sock_no_getsockopt,
2651 .sendmsg = packet_sendmsg_spkt,
2652 .recvmsg = packet_recvmsg,
2653 .mmap = sock_no_mmap,
2654 .sendpage = sock_no_sendpage,
2655 };
2656
2657 static const struct proto_ops packet_ops = {
2658 .family = PF_PACKET,
2659 .owner = THIS_MODULE,
2660 .release = packet_release,
2661 .bind = packet_bind,
2662 .connect = sock_no_connect,
2663 .socketpair = sock_no_socketpair,
2664 .accept = sock_no_accept,
2665 .getname = packet_getname,
2666 .poll = packet_poll,
2667 .ioctl = packet_ioctl,
2668 .listen = sock_no_listen,
2669 .shutdown = sock_no_shutdown,
2670 .setsockopt = packet_setsockopt,
2671 .getsockopt = packet_getsockopt,
2672 .sendmsg = packet_sendmsg,
2673 .recvmsg = packet_recvmsg,
2674 .mmap = packet_mmap,
2675 .sendpage = sock_no_sendpage,
2676 };
2677
2678 static const struct net_proto_family packet_family_ops = {
2679 .family = PF_PACKET,
2680 .create = packet_create,
2681 .owner = THIS_MODULE,
2682 };
2683
2684 static struct notifier_block packet_netdev_notifier = {
2685 .notifier_call = packet_notifier,
2686 };
2687
2688 #ifdef CONFIG_PROC_FS
2689
2690 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2691 __acquires(RCU)
2692 {
2693 struct net *net = seq_file_net(seq);
2694
2695 rcu_read_lock();
2696 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
2697 }
2698
2699 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2700 {
2701 struct net *net = seq_file_net(seq);
2702 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
2703 }
2704
2705 static void packet_seq_stop(struct seq_file *seq, void *v)
2706 __releases(RCU)
2707 {
2708 rcu_read_unlock();
2709 }
2710
2711 static int packet_seq_show(struct seq_file *seq, void *v)
2712 {
2713 if (v == SEQ_START_TOKEN)
2714 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
2715 else {
2716 struct sock *s = sk_entry(v);
2717 const struct packet_sock *po = pkt_sk(s);
2718
2719 seq_printf(seq,
2720 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
2721 s,
2722 atomic_read(&s->sk_refcnt),
2723 s->sk_type,
2724 ntohs(po->num),
2725 po->ifindex,
2726 po->running,
2727 atomic_read(&s->sk_rmem_alloc),
2728 sock_i_uid(s),
2729 sock_i_ino(s));
2730 }
2731
2732 return 0;
2733 }
2734
2735 static const struct seq_operations packet_seq_ops = {
2736 .start = packet_seq_start,
2737 .next = packet_seq_next,
2738 .stop = packet_seq_stop,
2739 .show = packet_seq_show,
2740 };
2741
2742 static int packet_seq_open(struct inode *inode, struct file *file)
2743 {
2744 return seq_open_net(inode, file, &packet_seq_ops,
2745 sizeof(struct seq_net_private));
2746 }
2747
2748 static const struct file_operations packet_seq_fops = {
2749 .owner = THIS_MODULE,
2750 .open = packet_seq_open,
2751 .read = seq_read,
2752 .llseek = seq_lseek,
2753 .release = seq_release_net,
2754 };
2755
2756 #endif
2757
2758 static int __net_init packet_net_init(struct net *net)
2759 {
2760 spin_lock_init(&net->packet.sklist_lock);
2761 INIT_HLIST_HEAD(&net->packet.sklist);
2762
2763 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
2764 return -ENOMEM;
2765
2766 return 0;
2767 }
2768
2769 static void __net_exit packet_net_exit(struct net *net)
2770 {
2771 proc_net_remove(net, "packet");
2772 }
2773
2774 static struct pernet_operations packet_net_ops = {
2775 .init = packet_net_init,
2776 .exit = packet_net_exit,
2777 };
2778
2779
2780 static void __exit packet_exit(void)
2781 {
2782 unregister_netdevice_notifier(&packet_netdev_notifier);
2783 unregister_pernet_subsys(&packet_net_ops);
2784 sock_unregister(PF_PACKET);
2785 proto_unregister(&packet_proto);
2786 }
2787
2788 static int __init packet_init(void)
2789 {
2790 int rc = proto_register(&packet_proto, 0);
2791
2792 if (rc != 0)
2793 goto out;
2794
2795 sock_register(&packet_family_ops);
2796 register_pernet_subsys(&packet_net_ops);
2797 register_netdevice_notifier(&packet_netdev_notifier);
2798 out:
2799 return rc;
2800 }
2801
2802 module_init(packet_init);
2803 module_exit(packet_exit);
2804 MODULE_LICENSE("GPL");
2805 MODULE_ALIAS_NETPROTO(PF_PACKET);
linux-next