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