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smsc911x: Add spinlocks around registers access
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / packet / af_packet.c
blob243946d4809d04584a8388c8183aaa4cb608d049
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 <net/net_namespace.h>
65 #include <net/ip.h>
66 #include <net/protocol.h>
67 #include <linux/skbuff.h>
68 #include <net/sock.h>
69 #include <linux/errno.h>
70 #include <linux/timer.h>
71 #include <asm/system.h>
72 #include <asm/uaccess.h>
73 #include <asm/ioctls.h>
74 #include <asm/page.h>
75 #include <asm/cacheflush.h>
76 #include <asm/io.h>
77 #include <linux/proc_fs.h>
78 #include <linux/seq_file.h>
79 #include <linux/poll.h>
80 #include <linux/module.h>
81 #include <linux/init.h>
82 #include <linux/mutex.h>
83 #include <linux/if_vlan.h>
84 #include <linux/virtio_net.h>
85
86 #ifdef CONFIG_INET
87 #include <net/inet_common.h>
88 #endif
89
90 /*
91 Assumptions:
92 - if device has no dev->hard_header routine, it adds and removes ll header
93 inside itself. In this case ll header is invisible outside of device,
94 but higher levels still should reserve dev->hard_header_len.
95 Some devices are enough clever to reallocate skb, when header
96 will not fit to reserved space (tunnel), another ones are silly
97 (PPP).
98 - packet socket receives packets with pulled ll header,
99 so that SOCK_RAW should push it back.
100
101 On receive:
102 -----------
103
104 Incoming, dev->hard_header!=NULL
105 mac_header -> ll header
106 data -> data
107
108 Outgoing, dev->hard_header!=NULL
109 mac_header -> ll header
110 data -> ll header
111
112 Incoming, dev->hard_header==NULL
113 mac_header -> UNKNOWN position. It is very likely, that it points to ll
114 header. PPP makes it, that is wrong, because introduce
115 assymetry between rx and tx paths.
116 data -> data
117
118 Outgoing, dev->hard_header==NULL
119 mac_header -> data. ll header is still not built!
120 data -> data
121
122 Resume
123 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
124
125
126 On transmit:
127 ------------
128
129 dev->hard_header != NULL
130 mac_header -> ll header
131 data -> ll header
132
133 dev->hard_header == NULL (ll header is added by device, we cannot control it)
134 mac_header -> data
135 data -> data
136
137 We should set nh.raw on output to correct posistion,
138 packet classifier depends on it.
139 */
140
141 /* Private packet socket structures. */
142
143 struct packet_mclist {
144 struct packet_mclist *next;
145 int ifindex;
146 int count;
147 unsigned short type;
148 unsigned short alen;
149 unsigned char addr[MAX_ADDR_LEN];
150 };
151 /* identical to struct packet_mreq except it has
152 * a longer address field.
153 */
154 struct packet_mreq_max {
155 int mr_ifindex;
156 unsigned short mr_type;
157 unsigned short mr_alen;
158 unsigned char mr_address[MAX_ADDR_LEN];
159 };
160
161 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
162 int closing, int tx_ring);
163
164 struct packet_ring_buffer {
165 char **pg_vec;
166 unsigned int head;
167 unsigned int frames_per_block;
168 unsigned int frame_size;
169 unsigned int frame_max;
170
171 unsigned int pg_vec_order;
172 unsigned int pg_vec_pages;
173 unsigned int pg_vec_len;
174
175 atomic_t pending;
176 };
177
178 struct packet_sock;
179 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
180
181 static void packet_flush_mclist(struct sock *sk);
182
183 struct packet_sock {
184 /* struct sock has to be the first member of packet_sock */
185 struct sock sk;
186 struct tpacket_stats stats;
187 struct packet_ring_buffer rx_ring;
188 struct packet_ring_buffer tx_ring;
189 int copy_thresh;
190 spinlock_t bind_lock;
191 struct mutex pg_vec_lock;
192 unsigned int running:1, /* prot_hook is attached*/
193 auxdata:1,
194 origdev:1,
195 has_vnet_hdr:1;
196 int ifindex; /* bound device */
197 __be16 num;
198 struct packet_mclist *mclist;
199 atomic_t mapped;
200 enum tpacket_versions tp_version;
201 unsigned int tp_hdrlen;
202 unsigned int tp_reserve;
203 unsigned int tp_loss:1;
204 struct packet_type prot_hook ____cacheline_aligned_in_smp;
205 };
206
207 struct packet_skb_cb {
208 unsigned int origlen;
209 union {
210 struct sockaddr_pkt pkt;
211 struct sockaddr_ll ll;
212 } sa;
213 };
214
215 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
216
217 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
218 {
219 union {
220 struct tpacket_hdr *h1;
221 struct tpacket2_hdr *h2;
222 void *raw;
223 } h;
224
225 h.raw = frame;
226 switch (po->tp_version) {
227 case TPACKET_V1:
228 h.h1->tp_status = status;
229 flush_dcache_page(virt_to_page(&h.h1->tp_status));
230 break;
231 case TPACKET_V2:
232 h.h2->tp_status = status;
233 flush_dcache_page(virt_to_page(&h.h2->tp_status));
234 break;
235 default:
236 pr_err("TPACKET version not supported\n");
237 BUG();
238 }
239
240 smp_wmb();
241 }
242
243 static int __packet_get_status(struct packet_sock *po, void *frame)
244 {
245 union {
246 struct tpacket_hdr *h1;
247 struct tpacket2_hdr *h2;
248 void *raw;
249 } h;
250
251 smp_rmb();
252
253 h.raw = frame;
254 switch (po->tp_version) {
255 case TPACKET_V1:
256 flush_dcache_page(virt_to_page(&h.h1->tp_status));
257 return h.h1->tp_status;
258 case TPACKET_V2:
259 flush_dcache_page(virt_to_page(&h.h2->tp_status));
260 return h.h2->tp_status;
261 default:
262 pr_err("TPACKET version not supported\n");
263 BUG();
264 return 0;
265 }
266 }
267
268 static void *packet_lookup_frame(struct packet_sock *po,
269 struct packet_ring_buffer *rb,
270 unsigned int position,
271 int status)
272 {
273 unsigned int pg_vec_pos, frame_offset;
274 union {
275 struct tpacket_hdr *h1;
276 struct tpacket2_hdr *h2;
277 void *raw;
278 } h;
279
280 pg_vec_pos = position / rb->frames_per_block;
281 frame_offset = position % rb->frames_per_block;
282
283 h.raw = rb->pg_vec[pg_vec_pos] + (frame_offset * rb->frame_size);
284
285 if (status != __packet_get_status(po, h.raw))
286 return NULL;
287
288 return h.raw;
289 }
290
291 static inline void *packet_current_frame(struct packet_sock *po,
292 struct packet_ring_buffer *rb,
293 int status)
294 {
295 return packet_lookup_frame(po, rb, rb->head, status);
296 }
297
298 static inline void *packet_previous_frame(struct packet_sock *po,
299 struct packet_ring_buffer *rb,
300 int status)
301 {
302 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
303 return packet_lookup_frame(po, rb, previous, status);
304 }
305
306 static inline void packet_increment_head(struct packet_ring_buffer *buff)
307 {
308 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
309 }
310
311 static inline struct packet_sock *pkt_sk(struct sock *sk)
312 {
313 return (struct packet_sock *)sk;
314 }
315
316 static void packet_sock_destruct(struct sock *sk)
317 {
318 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
319 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
320
321 if (!sock_flag(sk, SOCK_DEAD)) {
322 pr_err("Attempt to release alive packet socket: %p\n", sk);
323 return;
324 }
325
326 sk_refcnt_debug_dec(sk);
327 }
328
329
330 static const struct proto_ops packet_ops;
331
332 static const struct proto_ops packet_ops_spkt;
333
334 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
335 struct packet_type *pt, struct net_device *orig_dev)
336 {
337 struct sock *sk;
338 struct sockaddr_pkt *spkt;
339
340 /*
341 * When we registered the protocol we saved the socket in the data
342 * field for just this event.
343 */
344
345 sk = pt->af_packet_priv;
346
347 /*
348 * Yank back the headers [hope the device set this
349 * right or kerboom...]
350 *
351 * Incoming packets have ll header pulled,
352 * push it back.
353 *
354 * For outgoing ones skb->data == skb_mac_header(skb)
355 * so that this procedure is noop.
356 */
357
358 if (skb->pkt_type == PACKET_LOOPBACK)
359 goto out;
360
361 if (!net_eq(dev_net(dev), sock_net(sk)))
362 goto out;
363
364 skb = skb_share_check(skb, GFP_ATOMIC);
365 if (skb == NULL)
366 goto oom;
367
368 /* drop any routing info */
369 skb_dst_drop(skb);
370
371 /* drop conntrack reference */
372 nf_reset(skb);
373
374 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
375
376 skb_push(skb, skb->data - skb_mac_header(skb));
377
378 /*
379 * The SOCK_PACKET socket receives _all_ frames.
380 */
381
382 spkt->spkt_family = dev->type;
383 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
384 spkt->spkt_protocol = skb->protocol;
385
386 /*
387 * Charge the memory to the socket. This is done specifically
388 * to prevent sockets using all the memory up.
389 */
390
391 if (sock_queue_rcv_skb(sk, skb) == 0)
392 return 0;
393
394 out:
395 kfree_skb(skb);
396 oom:
397 return 0;
398 }
399
400
401 /*
402 * Output a raw packet to a device layer. This bypasses all the other
403 * protocol layers and you must therefore supply it with a complete frame
404 */
405
406 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
407 struct msghdr *msg, size_t len)
408 {
409 struct sock *sk = sock->sk;
410 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
411 struct sk_buff *skb = NULL;
412 struct net_device *dev;
413 __be16 proto = 0;
414 int err;
415
416 /*
417 * Get and verify the address.
418 */
419
420 if (saddr) {
421 if (msg->msg_namelen < sizeof(struct sockaddr))
422 return -EINVAL;
423 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
424 proto = saddr->spkt_protocol;
425 } else
426 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
427
428 /*
429 * Find the device first to size check it
430 */
431
432 saddr->spkt_device[13] = 0;
433 retry:
434 rcu_read_lock();
435 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
436 err = -ENODEV;
437 if (dev == NULL)
438 goto out_unlock;
439
440 err = -ENETDOWN;
441 if (!(dev->flags & IFF_UP))
442 goto out_unlock;
443
444 /*
445 * You may not queue a frame bigger than the mtu. This is the lowest level
446 * raw protocol and you must do your own fragmentation at this level.
447 */
448
449 err = -EMSGSIZE;
450 if (len > dev->mtu + dev->hard_header_len)
451 goto out_unlock;
452
453 if (!skb) {
454 size_t reserved = LL_RESERVED_SPACE(dev);
455 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
456
457 rcu_read_unlock();
458 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
459 if (skb == NULL)
460 return -ENOBUFS;
461 /* FIXME: Save some space for broken drivers that write a hard
462 * header at transmission time by themselves. PPP is the notable
463 * one here. This should really be fixed at the driver level.
464 */
465 skb_reserve(skb, reserved);
466 skb_reset_network_header(skb);
467
468 /* Try to align data part correctly */
469 if (hhlen) {
470 skb->data -= hhlen;
471 skb->tail -= hhlen;
472 if (len < hhlen)
473 skb_reset_network_header(skb);
474 }
475 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
476 if (err)
477 goto out_free;
478 goto retry;
479 }
480
481
482 skb->protocol = proto;
483 skb->dev = dev;
484 skb->priority = sk->sk_priority;
485 skb->mark = sk->sk_mark;
486
487 dev_queue_xmit(skb);
488 rcu_read_unlock();
489 return len;
490
491 out_unlock:
492 rcu_read_unlock();
493 out_free:
494 kfree_skb(skb);
495 return err;
496 }
497
498 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
499 unsigned int res)
500 {
501 struct sk_filter *filter;
502
503 rcu_read_lock_bh();
504 filter = rcu_dereference_bh(sk->sk_filter);
505 if (filter != NULL)
506 res = sk_run_filter(skb, filter->insns, filter->len);
507 rcu_read_unlock_bh();
508
509 return res;
510 }
511
512 /*
513 This function makes lazy skb cloning in hope that most of packets
514 are discarded by BPF.
515
516 Note tricky part: we DO mangle shared skb! skb->data, skb->len
517 and skb->cb are mangled. It works because (and until) packets
518 falling here are owned by current CPU. Output packets are cloned
519 by dev_queue_xmit_nit(), input packets are processed by net_bh
520 sequencially, so that if we return skb to original state on exit,
521 we will not harm anyone.
522 */
523
524 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
525 struct packet_type *pt, struct net_device *orig_dev)
526 {
527 struct sock *sk;
528 struct sockaddr_ll *sll;
529 struct packet_sock *po;
530 u8 *skb_head = skb->data;
531 int skb_len = skb->len;
532 unsigned int snaplen, res;
533
534 if (skb->pkt_type == PACKET_LOOPBACK)
535 goto drop;
536
537 sk = pt->af_packet_priv;
538 po = pkt_sk(sk);
539
540 if (!net_eq(dev_net(dev), sock_net(sk)))
541 goto drop;
542
543 skb->dev = dev;
544
545 if (dev->header_ops) {
546 /* The device has an explicit notion of ll header,
547 exported to higher levels.
548
549 Otherwise, the device hides datails of it frame
550 structure, so that corresponding packet head
551 never delivered to user.
552 */
553 if (sk->sk_type != SOCK_DGRAM)
554 skb_push(skb, skb->data - skb_mac_header(skb));
555 else if (skb->pkt_type == PACKET_OUTGOING) {
556 /* Special case: outgoing packets have ll header at head */
557 skb_pull(skb, skb_network_offset(skb));
558 }
559 }
560
561 snaplen = skb->len;
562
563 res = run_filter(skb, sk, snaplen);
564 if (!res)
565 goto drop_n_restore;
566 if (snaplen > res)
567 snaplen = res;
568
569 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
570 (unsigned)sk->sk_rcvbuf)
571 goto drop_n_acct;
572
573 if (skb_shared(skb)) {
574 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
575 if (nskb == NULL)
576 goto drop_n_acct;
577
578 if (skb_head != skb->data) {
579 skb->data = skb_head;
580 skb->len = skb_len;
581 }
582 kfree_skb(skb);
583 skb = nskb;
584 }
585
586 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
587 sizeof(skb->cb));
588
589 sll = &PACKET_SKB_CB(skb)->sa.ll;
590 sll->sll_family = AF_PACKET;
591 sll->sll_hatype = dev->type;
592 sll->sll_protocol = skb->protocol;
593 sll->sll_pkttype = skb->pkt_type;
594 if (unlikely(po->origdev))
595 sll->sll_ifindex = orig_dev->ifindex;
596 else
597 sll->sll_ifindex = dev->ifindex;
598
599 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
600
601 PACKET_SKB_CB(skb)->origlen = skb->len;
602
603 if (pskb_trim(skb, snaplen))
604 goto drop_n_acct;
605
606 skb_set_owner_r(skb, sk);
607 skb->dev = NULL;
608 skb_dst_drop(skb);
609
610 /* drop conntrack reference */
611 nf_reset(skb);
612
613 spin_lock(&sk->sk_receive_queue.lock);
614 po->stats.tp_packets++;
615 skb->dropcount = atomic_read(&sk->sk_drops);
616 __skb_queue_tail(&sk->sk_receive_queue, skb);
617 spin_unlock(&sk->sk_receive_queue.lock);
618 sk->sk_data_ready(sk, skb->len);
619 return 0;
620
621 drop_n_acct:
622 po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
623
624 drop_n_restore:
625 if (skb_head != skb->data && skb_shared(skb)) {
626 skb->data = skb_head;
627 skb->len = skb_len;
628 }
629 drop:
630 consume_skb(skb);
631 return 0;
632 }
633
634 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
635 struct packet_type *pt, struct net_device *orig_dev)
636 {
637 struct sock *sk;
638 struct packet_sock *po;
639 struct sockaddr_ll *sll;
640 union {
641 struct tpacket_hdr *h1;
642 struct tpacket2_hdr *h2;
643 void *raw;
644 } h;
645 u8 *skb_head = skb->data;
646 int skb_len = skb->len;
647 unsigned int snaplen, res;
648 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
649 unsigned short macoff, netoff, hdrlen;
650 struct sk_buff *copy_skb = NULL;
651 struct timeval tv;
652 struct timespec ts;
653
654 if (skb->pkt_type == PACKET_LOOPBACK)
655 goto drop;
656
657 sk = pt->af_packet_priv;
658 po = pkt_sk(sk);
659
660 if (!net_eq(dev_net(dev), sock_net(sk)))
661 goto drop;
662
663 if (dev->header_ops) {
664 if (sk->sk_type != SOCK_DGRAM)
665 skb_push(skb, skb->data - skb_mac_header(skb));
666 else if (skb->pkt_type == PACKET_OUTGOING) {
667 /* Special case: outgoing packets have ll header at head */
668 skb_pull(skb, skb_network_offset(skb));
669 }
670 }
671
672 if (skb->ip_summed == CHECKSUM_PARTIAL)
673 status |= TP_STATUS_CSUMNOTREADY;
674
675 snaplen = skb->len;
676
677 res = run_filter(skb, sk, snaplen);
678 if (!res)
679 goto drop_n_restore;
680 if (snaplen > res)
681 snaplen = res;
682
683 if (sk->sk_type == SOCK_DGRAM) {
684 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
685 po->tp_reserve;
686 } else {
687 unsigned maclen = skb_network_offset(skb);
688 netoff = TPACKET_ALIGN(po->tp_hdrlen +
689 (maclen < 16 ? 16 : maclen)) +
690 po->tp_reserve;
691 macoff = netoff - maclen;
692 }
693
694 if (macoff + snaplen > po->rx_ring.frame_size) {
695 if (po->copy_thresh &&
696 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
697 (unsigned)sk->sk_rcvbuf) {
698 if (skb_shared(skb)) {
699 copy_skb = skb_clone(skb, GFP_ATOMIC);
700 } else {
701 copy_skb = skb_get(skb);
702 skb_head = skb->data;
703 }
704 if (copy_skb)
705 skb_set_owner_r(copy_skb, sk);
706 }
707 snaplen = po->rx_ring.frame_size - macoff;
708 if ((int)snaplen < 0)
709 snaplen = 0;
710 }
711
712 spin_lock(&sk->sk_receive_queue.lock);
713 h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
714 if (!h.raw)
715 goto ring_is_full;
716 packet_increment_head(&po->rx_ring);
717 po->stats.tp_packets++;
718 if (copy_skb) {
719 status |= TP_STATUS_COPY;
720 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
721 }
722 if (!po->stats.tp_drops)
723 status &= ~TP_STATUS_LOSING;
724 spin_unlock(&sk->sk_receive_queue.lock);
725
726 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
727
728 switch (po->tp_version) {
729 case TPACKET_V1:
730 h.h1->tp_len = skb->len;
731 h.h1->tp_snaplen = snaplen;
732 h.h1->tp_mac = macoff;
733 h.h1->tp_net = netoff;
734 if (skb->tstamp.tv64)
735 tv = ktime_to_timeval(skb->tstamp);
736 else
737 do_gettimeofday(&tv);
738 h.h1->tp_sec = tv.tv_sec;
739 h.h1->tp_usec = tv.tv_usec;
740 hdrlen = sizeof(*h.h1);
741 break;
742 case TPACKET_V2:
743 h.h2->tp_len = skb->len;
744 h.h2->tp_snaplen = snaplen;
745 h.h2->tp_mac = macoff;
746 h.h2->tp_net = netoff;
747 if (skb->tstamp.tv64)
748 ts = ktime_to_timespec(skb->tstamp);
749 else
750 getnstimeofday(&ts);
751 h.h2->tp_sec = ts.tv_sec;
752 h.h2->tp_nsec = ts.tv_nsec;
753 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
754 hdrlen = sizeof(*h.h2);
755 break;
756 default:
757 BUG();
758 }
759
760 sll = h.raw + TPACKET_ALIGN(hdrlen);
761 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
762 sll->sll_family = AF_PACKET;
763 sll->sll_hatype = dev->type;
764 sll->sll_protocol = skb->protocol;
765 sll->sll_pkttype = skb->pkt_type;
766 if (unlikely(po->origdev))
767 sll->sll_ifindex = orig_dev->ifindex;
768 else
769 sll->sll_ifindex = dev->ifindex;
770
771 __packet_set_status(po, h.raw, status);
772 smp_mb();
773 {
774 struct page *p_start, *p_end;
775 u8 *h_end = h.raw + macoff + snaplen - 1;
776
777 p_start = virt_to_page(h.raw);
778 p_end = virt_to_page(h_end);
779 while (p_start <= p_end) {
780 flush_dcache_page(p_start);
781 p_start++;
782 }
783 }
784
785 sk->sk_data_ready(sk, 0);
786
787 drop_n_restore:
788 if (skb_head != skb->data && skb_shared(skb)) {
789 skb->data = skb_head;
790 skb->len = skb_len;
791 }
792 drop:
793 kfree_skb(skb);
794 return 0;
795
796 ring_is_full:
797 po->stats.tp_drops++;
798 spin_unlock(&sk->sk_receive_queue.lock);
799
800 sk->sk_data_ready(sk, 0);
801 kfree_skb(copy_skb);
802 goto drop_n_restore;
803 }
804
805 static void tpacket_destruct_skb(struct sk_buff *skb)
806 {
807 struct packet_sock *po = pkt_sk(skb->sk);
808 void *ph;
809
810 BUG_ON(skb == NULL);
811
812 if (likely(po->tx_ring.pg_vec)) {
813 ph = skb_shinfo(skb)->destructor_arg;
814 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
815 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
816 atomic_dec(&po->tx_ring.pending);
817 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
818 }
819
820 sock_wfree(skb);
821 }
822
823 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
824 void *frame, struct net_device *dev, int size_max,
825 __be16 proto, unsigned char *addr)
826 {
827 union {
828 struct tpacket_hdr *h1;
829 struct tpacket2_hdr *h2;
830 void *raw;
831 } ph;
832 int to_write, offset, len, tp_len, nr_frags, len_max;
833 struct socket *sock = po->sk.sk_socket;
834 struct page *page;
835 void *data;
836 int err;
837
838 ph.raw = frame;
839
840 skb->protocol = proto;
841 skb->dev = dev;
842 skb->priority = po->sk.sk_priority;
843 skb->mark = po->sk.sk_mark;
844 skb_shinfo(skb)->destructor_arg = ph.raw;
845
846 switch (po->tp_version) {
847 case TPACKET_V2:
848 tp_len = ph.h2->tp_len;
849 break;
850 default:
851 tp_len = ph.h1->tp_len;
852 break;
853 }
854 if (unlikely(tp_len > size_max)) {
855 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
856 return -EMSGSIZE;
857 }
858
859 skb_reserve(skb, LL_RESERVED_SPACE(dev));
860 skb_reset_network_header(skb);
861
862 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
863 to_write = tp_len;
864
865 if (sock->type == SOCK_DGRAM) {
866 err = dev_hard_header(skb, dev, ntohs(proto), addr,
867 NULL, tp_len);
868 if (unlikely(err < 0))
869 return -EINVAL;
870 } else if (dev->hard_header_len) {
871 /* net device doesn't like empty head */
872 if (unlikely(tp_len <= dev->hard_header_len)) {
873 pr_err("packet size is too short (%d < %d)\n",
874 tp_len, dev->hard_header_len);
875 return -EINVAL;
876 }
877
878 skb_push(skb, dev->hard_header_len);
879 err = skb_store_bits(skb, 0, data,
880 dev->hard_header_len);
881 if (unlikely(err))
882 return err;
883
884 data += dev->hard_header_len;
885 to_write -= dev->hard_header_len;
886 }
887
888 err = -EFAULT;
889 page = virt_to_page(data);
890 offset = offset_in_page(data);
891 len_max = PAGE_SIZE - offset;
892 len = ((to_write > len_max) ? len_max : to_write);
893
894 skb->data_len = to_write;
895 skb->len += to_write;
896 skb->truesize += to_write;
897 atomic_add(to_write, &po->sk.sk_wmem_alloc);
898
899 while (likely(to_write)) {
900 nr_frags = skb_shinfo(skb)->nr_frags;
901
902 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
903 pr_err("Packet exceed the number of skb frags(%lu)\n",
904 MAX_SKB_FRAGS);
905 return -EFAULT;
906 }
907
908 flush_dcache_page(page);
909 get_page(page);
910 skb_fill_page_desc(skb,
911 nr_frags,
912 page++, offset, len);
913 to_write -= len;
914 offset = 0;
915 len_max = PAGE_SIZE;
916 len = ((to_write > len_max) ? len_max : to_write);
917 }
918
919 return tp_len;
920 }
921
922 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
923 {
924 struct socket *sock;
925 struct sk_buff *skb;
926 struct net_device *dev;
927 __be16 proto;
928 int ifindex, err, reserve = 0;
929 void *ph;
930 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
931 int tp_len, size_max;
932 unsigned char *addr;
933 int len_sum = 0;
934 int status = 0;
935
936 sock = po->sk.sk_socket;
937
938 mutex_lock(&po->pg_vec_lock);
939
940 err = -EBUSY;
941 if (saddr == NULL) {
942 ifindex = po->ifindex;
943 proto = po->num;
944 addr = NULL;
945 } else {
946 err = -EINVAL;
947 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
948 goto out;
949 if (msg->msg_namelen < (saddr->sll_halen
950 + offsetof(struct sockaddr_ll,
951 sll_addr)))
952 goto out;
953 ifindex = saddr->sll_ifindex;
954 proto = saddr->sll_protocol;
955 addr = saddr->sll_addr;
956 }
957
958 dev = dev_get_by_index(sock_net(&po->sk), ifindex);
959 err = -ENXIO;
960 if (unlikely(dev == NULL))
961 goto out;
962
963 reserve = dev->hard_header_len;
964
965 err = -ENETDOWN;
966 if (unlikely(!(dev->flags & IFF_UP)))
967 goto out_put;
968
969 size_max = po->tx_ring.frame_size
970 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
971
972 if (size_max > dev->mtu + reserve)
973 size_max = dev->mtu + reserve;
974
975 do {
976 ph = packet_current_frame(po, &po->tx_ring,
977 TP_STATUS_SEND_REQUEST);
978
979 if (unlikely(ph == NULL)) {
980 schedule();
981 continue;
982 }
983
984 status = TP_STATUS_SEND_REQUEST;
985 skb = sock_alloc_send_skb(&po->sk,
986 LL_ALLOCATED_SPACE(dev)
987 + sizeof(struct sockaddr_ll),
988 0, &err);
989
990 if (unlikely(skb == NULL))
991 goto out_status;
992
993 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
994 addr);
995
996 if (unlikely(tp_len < 0)) {
997 if (po->tp_loss) {
998 __packet_set_status(po, ph,
999 TP_STATUS_AVAILABLE);
1000 packet_increment_head(&po->tx_ring);
1001 kfree_skb(skb);
1002 continue;
1003 } else {
1004 status = TP_STATUS_WRONG_FORMAT;
1005 err = tp_len;
1006 goto out_status;
1007 }
1008 }
1009
1010 skb->destructor = tpacket_destruct_skb;
1011 __packet_set_status(po, ph, TP_STATUS_SENDING);
1012 atomic_inc(&po->tx_ring.pending);
1013
1014 status = TP_STATUS_SEND_REQUEST;
1015 err = dev_queue_xmit(skb);
1016 if (unlikely(err > 0)) {
1017 err = net_xmit_errno(err);
1018 if (err && __packet_get_status(po, ph) ==
1019 TP_STATUS_AVAILABLE) {
1020 /* skb was destructed already */
1021 skb = NULL;
1022 goto out_status;
1023 }
1024 /*
1025 * skb was dropped but not destructed yet;
1026 * let's treat it like congestion or err < 0
1027 */
1028 err = 0;
1029 }
1030 packet_increment_head(&po->tx_ring);
1031 len_sum += tp_len;
1032 } while (likely((ph != NULL) ||
1033 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
1034 (atomic_read(&po->tx_ring.pending))))
1035 );
1036
1037 err = len_sum;
1038 goto out_put;
1039
1040 out_status:
1041 __packet_set_status(po, ph, status);
1042 kfree_skb(skb);
1043 out_put:
1044 dev_put(dev);
1045 out:
1046 mutex_unlock(&po->pg_vec_lock);
1047 return err;
1048 }
1049
1050 static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
1051 size_t reserve, size_t len,
1052 size_t linear, int noblock,
1053 int *err)
1054 {
1055 struct sk_buff *skb;
1056
1057 /* Under a page? Don't bother with paged skb. */
1058 if (prepad + len < PAGE_SIZE || !linear)
1059 linear = len;
1060
1061 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
1062 err);
1063 if (!skb)
1064 return NULL;
1065
1066 skb_reserve(skb, reserve);
1067 skb_put(skb, linear);
1068 skb->data_len = len - linear;
1069 skb->len += len - linear;
1070
1071 return skb;
1072 }
1073
1074 static int packet_snd(struct socket *sock,
1075 struct msghdr *msg, size_t len)
1076 {
1077 struct sock *sk = sock->sk;
1078 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
1079 struct sk_buff *skb;
1080 struct net_device *dev;
1081 __be16 proto;
1082 unsigned char *addr;
1083 int ifindex, err, reserve = 0;
1084 struct virtio_net_hdr vnet_hdr = { 0 };
1085 int offset = 0;
1086 int vnet_hdr_len;
1087 struct packet_sock *po = pkt_sk(sk);
1088 unsigned short gso_type = 0;
1089
1090 /*
1091 * Get and verify the address.
1092 */
1093
1094 if (saddr == NULL) {
1095 ifindex = po->ifindex;
1096 proto = po->num;
1097 addr = NULL;
1098 } else {
1099 err = -EINVAL;
1100 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
1101 goto out;
1102 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
1103 goto out;
1104 ifindex = saddr->sll_ifindex;
1105 proto = saddr->sll_protocol;
1106 addr = saddr->sll_addr;
1107 }
1108
1109
1110 dev = dev_get_by_index(sock_net(sk), ifindex);
1111 err = -ENXIO;
1112 if (dev == NULL)
1113 goto out_unlock;
1114 if (sock->type == SOCK_RAW)
1115 reserve = dev->hard_header_len;
1116
1117 err = -ENETDOWN;
1118 if (!(dev->flags & IFF_UP))
1119 goto out_unlock;
1120
1121 if (po->has_vnet_hdr) {
1122 vnet_hdr_len = sizeof(vnet_hdr);
1123
1124 err = -EINVAL;
1125 if (len < vnet_hdr_len)
1126 goto out_unlock;
1127
1128 len -= vnet_hdr_len;
1129
1130 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
1131 vnet_hdr_len);
1132 if (err < 0)
1133 goto out_unlock;
1134
1135 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
1136 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
1137 vnet_hdr.hdr_len))
1138 vnet_hdr.hdr_len = vnet_hdr.csum_start +
1139 vnet_hdr.csum_offset + 2;
1140
1141 err = -EINVAL;
1142 if (vnet_hdr.hdr_len > len)
1143 goto out_unlock;
1144
1145 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
1146 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
1147 case VIRTIO_NET_HDR_GSO_TCPV4:
1148 gso_type = SKB_GSO_TCPV4;
1149 break;
1150 case VIRTIO_NET_HDR_GSO_TCPV6:
1151 gso_type = SKB_GSO_TCPV6;
1152 break;
1153 case VIRTIO_NET_HDR_GSO_UDP:
1154 gso_type = SKB_GSO_UDP;
1155 break;
1156 default:
1157 goto out_unlock;
1158 }
1159
1160 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
1161 gso_type |= SKB_GSO_TCP_ECN;
1162
1163 if (vnet_hdr.gso_size == 0)
1164 goto out_unlock;
1165
1166 }
1167 }
1168
1169 err = -EMSGSIZE;
1170 if (!gso_type && (len > dev->mtu+reserve))
1171 goto out_unlock;
1172
1173 err = -ENOBUFS;
1174 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
1175 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
1176 msg->msg_flags & MSG_DONTWAIT, &err);
1177 if (skb == NULL)
1178 goto out_unlock;
1179
1180 skb_set_network_header(skb, reserve);
1181
1182 err = -EINVAL;
1183 if (sock->type == SOCK_DGRAM &&
1184 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1185 goto out_free;
1186
1187 /* Returns -EFAULT on error */
1188 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
1189 if (err)
1190 goto out_free;
1191
1192 skb->protocol = proto;
1193 skb->dev = dev;
1194 skb->priority = sk->sk_priority;
1195 skb->mark = sk->sk_mark;
1196
1197 if (po->has_vnet_hdr) {
1198 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1199 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
1200 vnet_hdr.csum_offset)) {
1201 err = -EINVAL;
1202 goto out_free;
1203 }
1204 }
1205
1206 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
1207 skb_shinfo(skb)->gso_type = gso_type;
1208
1209 /* Header must be checked, and gso_segs computed. */
1210 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
1211 skb_shinfo(skb)->gso_segs = 0;
1212
1213 len += vnet_hdr_len;
1214 }
1215
1216 /*
1217 * Now send it
1218 */
1219
1220 err = dev_queue_xmit(skb);
1221 if (err > 0 && (err = net_xmit_errno(err)) != 0)
1222 goto out_unlock;
1223
1224 dev_put(dev);
1225
1226 return len;
1227
1228 out_free:
1229 kfree_skb(skb);
1230 out_unlock:
1231 if (dev)
1232 dev_put(dev);
1233 out:
1234 return err;
1235 }
1236
1237 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
1238 struct msghdr *msg, size_t len)
1239 {
1240 struct sock *sk = sock->sk;
1241 struct packet_sock *po = pkt_sk(sk);
1242 if (po->tx_ring.pg_vec)
1243 return tpacket_snd(po, msg);
1244 else
1245 return packet_snd(sock, msg, len);
1246 }
1247
1248 /*
1249 * Close a PACKET socket. This is fairly simple. We immediately go
1250 * to 'closed' state and remove our protocol entry in the device list.
1251 */
1252
1253 static int packet_release(struct socket *sock)
1254 {
1255 struct sock *sk = sock->sk;
1256 struct packet_sock *po;
1257 struct net *net;
1258 struct tpacket_req req;
1259
1260 if (!sk)
1261 return 0;
1262
1263 net = sock_net(sk);
1264 po = pkt_sk(sk);
1265
1266 spin_lock_bh(&net->packet.sklist_lock);
1267 sk_del_node_init_rcu(sk);
1268 sock_prot_inuse_add(net, sk->sk_prot, -1);
1269 spin_unlock_bh(&net->packet.sklist_lock);
1270
1271 spin_lock(&po->bind_lock);
1272 if (po->running) {
1273 /*
1274 * Remove from protocol table
1275 */
1276 po->running = 0;
1277 po->num = 0;
1278 __dev_remove_pack(&po->prot_hook);
1279 __sock_put(sk);
1280 }
1281 spin_unlock(&po->bind_lock);
1282
1283 packet_flush_mclist(sk);
1284
1285 memset(&req, 0, sizeof(req));
1286
1287 if (po->rx_ring.pg_vec)
1288 packet_set_ring(sk, &req, 1, 0);
1289
1290 if (po->tx_ring.pg_vec)
1291 packet_set_ring(sk, &req, 1, 1);
1292
1293 synchronize_net();
1294 /*
1295 * Now the socket is dead. No more input will appear.
1296 */
1297 sock_orphan(sk);
1298 sock->sk = NULL;
1299
1300 /* Purge queues */
1301
1302 skb_queue_purge(&sk->sk_receive_queue);
1303 sk_refcnt_debug_release(sk);
1304
1305 sock_put(sk);
1306 return 0;
1307 }
1308
1309 /*
1310 * Attach a packet hook.
1311 */
1312
1313 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
1314 {
1315 struct packet_sock *po = pkt_sk(sk);
1316 /*
1317 * Detach an existing hook if present.
1318 */
1319
1320 lock_sock(sk);
1321
1322 spin_lock(&po->bind_lock);
1323 if (po->running) {
1324 __sock_put(sk);
1325 po->running = 0;
1326 po->num = 0;
1327 spin_unlock(&po->bind_lock);
1328 dev_remove_pack(&po->prot_hook);
1329 spin_lock(&po->bind_lock);
1330 }
1331
1332 po->num = protocol;
1333 po->prot_hook.type = protocol;
1334 po->prot_hook.dev = dev;
1335
1336 po->ifindex = dev ? dev->ifindex : 0;
1337
1338 if (protocol == 0)
1339 goto out_unlock;
1340
1341 if (!dev || (dev->flags & IFF_UP)) {
1342 dev_add_pack(&po->prot_hook);
1343 sock_hold(sk);
1344 po->running = 1;
1345 } else {
1346 sk->sk_err = ENETDOWN;
1347 if (!sock_flag(sk, SOCK_DEAD))
1348 sk->sk_error_report(sk);
1349 }
1350
1351 out_unlock:
1352 spin_unlock(&po->bind_lock);
1353 release_sock(sk);
1354 return 0;
1355 }
1356
1357 /*
1358 * Bind a packet socket to a device
1359 */
1360
1361 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
1362 int addr_len)
1363 {
1364 struct sock *sk = sock->sk;
1365 char name[15];
1366 struct net_device *dev;
1367 int err = -ENODEV;
1368
1369 /*
1370 * Check legality
1371 */
1372
1373 if (addr_len != sizeof(struct sockaddr))
1374 return -EINVAL;
1375 strlcpy(name, uaddr->sa_data, sizeof(name));
1376
1377 dev = dev_get_by_name(sock_net(sk), name);
1378 if (dev) {
1379 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
1380 dev_put(dev);
1381 }
1382 return err;
1383 }
1384
1385 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1386 {
1387 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
1388 struct sock *sk = sock->sk;
1389 struct net_device *dev = NULL;
1390 int err;
1391
1392
1393 /*
1394 * Check legality
1395 */
1396
1397 if (addr_len < sizeof(struct sockaddr_ll))
1398 return -EINVAL;
1399 if (sll->sll_family != AF_PACKET)
1400 return -EINVAL;
1401
1402 if (sll->sll_ifindex) {
1403 err = -ENODEV;
1404 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1405 if (dev == NULL)
1406 goto out;
1407 }
1408 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1409 if (dev)
1410 dev_put(dev);
1411
1412 out:
1413 return err;
1414 }
1415
1416 static struct proto packet_proto = {
1417 .name = "PACKET",
1418 .owner = THIS_MODULE,
1419 .obj_size = sizeof(struct packet_sock),
1420 };
1421
1422 /*
1423 * Create a packet of type SOCK_PACKET.
1424 */
1425
1426 static int packet_create(struct net *net, struct socket *sock, int protocol,
1427 int kern)
1428 {
1429 struct sock *sk;
1430 struct packet_sock *po;
1431 __be16 proto = (__force __be16)protocol; /* weird, but documented */
1432 int err;
1433
1434 if (!capable(CAP_NET_RAW))
1435 return -EPERM;
1436 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1437 sock->type != SOCK_PACKET)
1438 return -ESOCKTNOSUPPORT;
1439
1440 sock->state = SS_UNCONNECTED;
1441
1442 err = -ENOBUFS;
1443 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1444 if (sk == NULL)
1445 goto out;
1446
1447 sock->ops = &packet_ops;
1448 if (sock->type == SOCK_PACKET)
1449 sock->ops = &packet_ops_spkt;
1450
1451 sock_init_data(sock, sk);
1452
1453 po = pkt_sk(sk);
1454 sk->sk_family = PF_PACKET;
1455 po->num = proto;
1456
1457 sk->sk_destruct = packet_sock_destruct;
1458 sk_refcnt_debug_inc(sk);
1459
1460 /*
1461 * Attach a protocol block
1462 */
1463
1464 spin_lock_init(&po->bind_lock);
1465 mutex_init(&po->pg_vec_lock);
1466 po->prot_hook.func = packet_rcv;
1467
1468 if (sock->type == SOCK_PACKET)
1469 po->prot_hook.func = packet_rcv_spkt;
1470
1471 po->prot_hook.af_packet_priv = sk;
1472
1473 if (proto) {
1474 po->prot_hook.type = proto;
1475 dev_add_pack(&po->prot_hook);
1476 sock_hold(sk);
1477 po->running = 1;
1478 }
1479
1480 spin_lock_bh(&net->packet.sklist_lock);
1481 sk_add_node_rcu(sk, &net->packet.sklist);
1482 sock_prot_inuse_add(net, &packet_proto, 1);
1483 spin_unlock_bh(&net->packet.sklist_lock);
1484
1485 return 0;
1486 out:
1487 return err;
1488 }
1489
1490 /*
1491 * Pull a packet from our receive queue and hand it to the user.
1492 * If necessary we block.
1493 */
1494
1495 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1496 struct msghdr *msg, size_t len, int flags)
1497 {
1498 struct sock *sk = sock->sk;
1499 struct sk_buff *skb;
1500 int copied, err;
1501 struct sockaddr_ll *sll;
1502 int vnet_hdr_len = 0;
1503
1504 err = -EINVAL;
1505 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1506 goto out;
1507
1508 #if 0
1509 /* What error should we return now? EUNATTACH? */
1510 if (pkt_sk(sk)->ifindex < 0)
1511 return -ENODEV;
1512 #endif
1513
1514 /*
1515 * Call the generic datagram receiver. This handles all sorts
1516 * of horrible races and re-entrancy so we can forget about it
1517 * in the protocol layers.
1518 *
1519 * Now it will return ENETDOWN, if device have just gone down,
1520 * but then it will block.
1521 */
1522
1523 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
1524
1525 /*
1526 * An error occurred so return it. Because skb_recv_datagram()
1527 * handles the blocking we don't see and worry about blocking
1528 * retries.
1529 */
1530
1531 if (skb == NULL)
1532 goto out;
1533
1534 if (pkt_sk(sk)->has_vnet_hdr) {
1535 struct virtio_net_hdr vnet_hdr = { 0 };
1536
1537 err = -EINVAL;
1538 vnet_hdr_len = sizeof(vnet_hdr);
1539 if ((len -= vnet_hdr_len) < 0)
1540 goto out_free;
1541
1542 if (skb_is_gso(skb)) {
1543 struct skb_shared_info *sinfo = skb_shinfo(skb);
1544
1545 /* This is a hint as to how much should be linear. */
1546 vnet_hdr.hdr_len = skb_headlen(skb);
1547 vnet_hdr.gso_size = sinfo->gso_size;
1548 if (sinfo->gso_type & SKB_GSO_TCPV4)
1549 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1550 else if (sinfo->gso_type & SKB_GSO_TCPV6)
1551 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1552 else if (sinfo->gso_type & SKB_GSO_UDP)
1553 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
1554 else if (sinfo->gso_type & SKB_GSO_FCOE)
1555 goto out_free;
1556 else
1557 BUG();
1558 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1559 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1560 } else
1561 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
1562
1563 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1564 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1565 vnet_hdr.csum_start = skb->csum_start -
1566 skb_headroom(skb);
1567 vnet_hdr.csum_offset = skb->csum_offset;
1568 } /* else everything is zero */
1569
1570 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
1571 vnet_hdr_len);
1572 if (err < 0)
1573 goto out_free;
1574 }
1575
1576 /*
1577 * If the address length field is there to be filled in, we fill
1578 * it in now.
1579 */
1580
1581 sll = &PACKET_SKB_CB(skb)->sa.ll;
1582 if (sock->type == SOCK_PACKET)
1583 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1584 else
1585 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1586
1587 /*
1588 * You lose any data beyond the buffer you gave. If it worries a
1589 * user program they can ask the device for its MTU anyway.
1590 */
1591
1592 copied = skb->len;
1593 if (copied > len) {
1594 copied = len;
1595 msg->msg_flags |= MSG_TRUNC;
1596 }
1597
1598 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1599 if (err)
1600 goto out_free;
1601
1602 sock_recv_ts_and_drops(msg, sk, skb);
1603
1604 if (msg->msg_name)
1605 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1606 msg->msg_namelen);
1607
1608 if (pkt_sk(sk)->auxdata) {
1609 struct tpacket_auxdata aux;
1610
1611 aux.tp_status = TP_STATUS_USER;
1612 if (skb->ip_summed == CHECKSUM_PARTIAL)
1613 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1614 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1615 aux.tp_snaplen = skb->len;
1616 aux.tp_mac = 0;
1617 aux.tp_net = skb_network_offset(skb);
1618 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
1619
1620 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1621 }
1622
1623 /*
1624 * Free or return the buffer as appropriate. Again this
1625 * hides all the races and re-entrancy issues from us.
1626 */
1627 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
1628
1629 out_free:
1630 skb_free_datagram(sk, skb);
1631 out:
1632 return err;
1633 }
1634
1635 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1636 int *uaddr_len, int peer)
1637 {
1638 struct net_device *dev;
1639 struct sock *sk = sock->sk;
1640
1641 if (peer)
1642 return -EOPNOTSUPP;
1643
1644 uaddr->sa_family = AF_PACKET;
1645 rcu_read_lock();
1646 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
1647 if (dev)
1648 strlcpy(uaddr->sa_data, dev->name, 15);
1649 else
1650 memset(uaddr->sa_data, 0, 14);
1651 rcu_read_unlock();
1652 *uaddr_len = sizeof(*uaddr);
1653
1654 return 0;
1655 }
1656
1657 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1658 int *uaddr_len, int peer)
1659 {
1660 struct net_device *dev;
1661 struct sock *sk = sock->sk;
1662 struct packet_sock *po = pkt_sk(sk);
1663 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
1664
1665 if (peer)
1666 return -EOPNOTSUPP;
1667
1668 sll->sll_family = AF_PACKET;
1669 sll->sll_ifindex = po->ifindex;
1670 sll->sll_protocol = po->num;
1671 rcu_read_lock();
1672 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
1673 if (dev) {
1674 sll->sll_hatype = dev->type;
1675 sll->sll_halen = dev->addr_len;
1676 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1677 } else {
1678 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
1679 sll->sll_halen = 0;
1680 }
1681 rcu_read_unlock();
1682 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1683
1684 return 0;
1685 }
1686
1687 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
1688 int what)
1689 {
1690 switch (i->type) {
1691 case PACKET_MR_MULTICAST:
1692 if (i->alen != dev->addr_len)
1693 return -EINVAL;
1694 if (what > 0)
1695 return dev_mc_add(dev, i->addr, i->alen, 0);
1696 else
1697 return dev_mc_delete(dev, i->addr, i->alen, 0);
1698 break;
1699 case PACKET_MR_PROMISC:
1700 return dev_set_promiscuity(dev, what);
1701 break;
1702 case PACKET_MR_ALLMULTI:
1703 return dev_set_allmulti(dev, what);
1704 break;
1705 case PACKET_MR_UNICAST:
1706 if (i->alen != dev->addr_len)
1707 return -EINVAL;
1708 if (what > 0)
1709 return dev_unicast_add(dev, i->addr);
1710 else
1711 return dev_unicast_delete(dev, i->addr);
1712 break;
1713 default:
1714 break;
1715 }
1716 return 0;
1717 }
1718
1719 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1720 {
1721 for ( ; i; i = i->next) {
1722 if (i->ifindex == dev->ifindex)
1723 packet_dev_mc(dev, i, what);
1724 }
1725 }
1726
1727 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1728 {
1729 struct packet_sock *po = pkt_sk(sk);
1730 struct packet_mclist *ml, *i;
1731 struct net_device *dev;
1732 int err;
1733
1734 rtnl_lock();
1735
1736 err = -ENODEV;
1737 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
1738 if (!dev)
1739 goto done;
1740
1741 err = -EINVAL;
1742 if (mreq->mr_alen > dev->addr_len)
1743 goto done;
1744
1745 err = -ENOBUFS;
1746 i = kmalloc(sizeof(*i), GFP_KERNEL);
1747 if (i == NULL)
1748 goto done;
1749
1750 err = 0;
1751 for (ml = po->mclist; ml; ml = ml->next) {
1752 if (ml->ifindex == mreq->mr_ifindex &&
1753 ml->type == mreq->mr_type &&
1754 ml->alen == mreq->mr_alen &&
1755 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1756 ml->count++;
1757 /* Free the new element ... */
1758 kfree(i);
1759 goto done;
1760 }
1761 }
1762
1763 i->type = mreq->mr_type;
1764 i->ifindex = mreq->mr_ifindex;
1765 i->alen = mreq->mr_alen;
1766 memcpy(i->addr, mreq->mr_address, i->alen);
1767 i->count = 1;
1768 i->next = po->mclist;
1769 po->mclist = i;
1770 err = packet_dev_mc(dev, i, 1);
1771 if (err) {
1772 po->mclist = i->next;
1773 kfree(i);
1774 }
1775
1776 done:
1777 rtnl_unlock();
1778 return err;
1779 }
1780
1781 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1782 {
1783 struct packet_mclist *ml, **mlp;
1784
1785 rtnl_lock();
1786
1787 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1788 if (ml->ifindex == mreq->mr_ifindex &&
1789 ml->type == mreq->mr_type &&
1790 ml->alen == mreq->mr_alen &&
1791 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1792 if (--ml->count == 0) {
1793 struct net_device *dev;
1794 *mlp = ml->next;
1795 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1796 if (dev)
1797 packet_dev_mc(dev, ml, -1);
1798 kfree(ml);
1799 }
1800 rtnl_unlock();
1801 return 0;
1802 }
1803 }
1804 rtnl_unlock();
1805 return -EADDRNOTAVAIL;
1806 }
1807
1808 static void packet_flush_mclist(struct sock *sk)
1809 {
1810 struct packet_sock *po = pkt_sk(sk);
1811 struct packet_mclist *ml;
1812
1813 if (!po->mclist)
1814 return;
1815
1816 rtnl_lock();
1817 while ((ml = po->mclist) != NULL) {
1818 struct net_device *dev;
1819
1820 po->mclist = ml->next;
1821 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1822 if (dev != NULL)
1823 packet_dev_mc(dev, ml, -1);
1824 kfree(ml);
1825 }
1826 rtnl_unlock();
1827 }
1828
1829 static int
1830 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
1831 {
1832 struct sock *sk = sock->sk;
1833 struct packet_sock *po = pkt_sk(sk);
1834 int ret;
1835
1836 if (level != SOL_PACKET)
1837 return -ENOPROTOOPT;
1838
1839 switch (optname) {
1840 case PACKET_ADD_MEMBERSHIP:
1841 case PACKET_DROP_MEMBERSHIP:
1842 {
1843 struct packet_mreq_max mreq;
1844 int len = optlen;
1845 memset(&mreq, 0, sizeof(mreq));
1846 if (len < sizeof(struct packet_mreq))
1847 return -EINVAL;
1848 if (len > sizeof(mreq))
1849 len = sizeof(mreq);
1850 if (copy_from_user(&mreq, optval, len))
1851 return -EFAULT;
1852 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1853 return -EINVAL;
1854 if (optname == PACKET_ADD_MEMBERSHIP)
1855 ret = packet_mc_add(sk, &mreq);
1856 else
1857 ret = packet_mc_drop(sk, &mreq);
1858 return ret;
1859 }
1860
1861 case PACKET_RX_RING:
1862 case PACKET_TX_RING:
1863 {
1864 struct tpacket_req req;
1865
1866 if (optlen < sizeof(req))
1867 return -EINVAL;
1868 if (pkt_sk(sk)->has_vnet_hdr)
1869 return -EINVAL;
1870 if (copy_from_user(&req, optval, sizeof(req)))
1871 return -EFAULT;
1872 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
1873 }
1874 case PACKET_COPY_THRESH:
1875 {
1876 int val;
1877
1878 if (optlen != sizeof(val))
1879 return -EINVAL;
1880 if (copy_from_user(&val, optval, sizeof(val)))
1881 return -EFAULT;
1882
1883 pkt_sk(sk)->copy_thresh = val;
1884 return 0;
1885 }
1886 case PACKET_VERSION:
1887 {
1888 int val;
1889
1890 if (optlen != sizeof(val))
1891 return -EINVAL;
1892 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1893 return -EBUSY;
1894 if (copy_from_user(&val, optval, sizeof(val)))
1895 return -EFAULT;
1896 switch (val) {
1897 case TPACKET_V1:
1898 case TPACKET_V2:
1899 po->tp_version = val;
1900 return 0;
1901 default:
1902 return -EINVAL;
1903 }
1904 }
1905 case PACKET_RESERVE:
1906 {
1907 unsigned int val;
1908
1909 if (optlen != sizeof(val))
1910 return -EINVAL;
1911 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1912 return -EBUSY;
1913 if (copy_from_user(&val, optval, sizeof(val)))
1914 return -EFAULT;
1915 po->tp_reserve = val;
1916 return 0;
1917 }
1918 case PACKET_LOSS:
1919 {
1920 unsigned int val;
1921
1922 if (optlen != sizeof(val))
1923 return -EINVAL;
1924 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1925 return -EBUSY;
1926 if (copy_from_user(&val, optval, sizeof(val)))
1927 return -EFAULT;
1928 po->tp_loss = !!val;
1929 return 0;
1930 }
1931 case PACKET_AUXDATA:
1932 {
1933 int val;
1934
1935 if (optlen < sizeof(val))
1936 return -EINVAL;
1937 if (copy_from_user(&val, optval, sizeof(val)))
1938 return -EFAULT;
1939
1940 po->auxdata = !!val;
1941 return 0;
1942 }
1943 case PACKET_ORIGDEV:
1944 {
1945 int val;
1946
1947 if (optlen < sizeof(val))
1948 return -EINVAL;
1949 if (copy_from_user(&val, optval, sizeof(val)))
1950 return -EFAULT;
1951
1952 po->origdev = !!val;
1953 return 0;
1954 }
1955 case PACKET_VNET_HDR:
1956 {
1957 int val;
1958
1959 if (sock->type != SOCK_RAW)
1960 return -EINVAL;
1961 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1962 return -EBUSY;
1963 if (optlen < sizeof(val))
1964 return -EINVAL;
1965 if (copy_from_user(&val, optval, sizeof(val)))
1966 return -EFAULT;
1967
1968 po->has_vnet_hdr = !!val;
1969 return 0;
1970 }
1971 default:
1972 return -ENOPROTOOPT;
1973 }
1974 }
1975
1976 static int packet_getsockopt(struct socket *sock, int level, int optname,
1977 char __user *optval, int __user *optlen)
1978 {
1979 int len;
1980 int val;
1981 struct sock *sk = sock->sk;
1982 struct packet_sock *po = pkt_sk(sk);
1983 void *data;
1984 struct tpacket_stats st;
1985
1986 if (level != SOL_PACKET)
1987 return -ENOPROTOOPT;
1988
1989 if (get_user(len, optlen))
1990 return -EFAULT;
1991
1992 if (len < 0)
1993 return -EINVAL;
1994
1995 switch (optname) {
1996 case PACKET_STATISTICS:
1997 if (len > sizeof(struct tpacket_stats))
1998 len = sizeof(struct tpacket_stats);
1999 spin_lock_bh(&sk->sk_receive_queue.lock);
2000 st = po->stats;
2001 memset(&po->stats, 0, sizeof(st));
2002 spin_unlock_bh(&sk->sk_receive_queue.lock);
2003 st.tp_packets += st.tp_drops;
2004
2005 data = &st;
2006 break;
2007 case PACKET_AUXDATA:
2008 if (len > sizeof(int))
2009 len = sizeof(int);
2010 val = po->auxdata;
2011
2012 data = &val;
2013 break;
2014 case PACKET_ORIGDEV:
2015 if (len > sizeof(int))
2016 len = sizeof(int);
2017 val = po->origdev;
2018
2019 data = &val;
2020 break;
2021 case PACKET_VNET_HDR:
2022 if (len > sizeof(int))
2023 len = sizeof(int);
2024 val = po->has_vnet_hdr;
2025
2026 data = &val;
2027 break;
2028 case PACKET_VERSION:
2029 if (len > sizeof(int))
2030 len = sizeof(int);
2031 val = po->tp_version;
2032 data = &val;
2033 break;
2034 case PACKET_HDRLEN:
2035 if (len > sizeof(int))
2036 len = sizeof(int);
2037 if (copy_from_user(&val, optval, len))
2038 return -EFAULT;
2039 switch (val) {
2040 case TPACKET_V1:
2041 val = sizeof(struct tpacket_hdr);
2042 break;
2043 case TPACKET_V2:
2044 val = sizeof(struct tpacket2_hdr);
2045 break;
2046 default:
2047 return -EINVAL;
2048 }
2049 data = &val;
2050 break;
2051 case PACKET_RESERVE:
2052 if (len > sizeof(unsigned int))
2053 len = sizeof(unsigned int);
2054 val = po->tp_reserve;
2055 data = &val;
2056 break;
2057 case PACKET_LOSS:
2058 if (len > sizeof(unsigned int))
2059 len = sizeof(unsigned int);
2060 val = po->tp_loss;
2061 data = &val;
2062 break;
2063 default:
2064 return -ENOPROTOOPT;
2065 }
2066
2067 if (put_user(len, optlen))
2068 return -EFAULT;
2069 if (copy_to_user(optval, data, len))
2070 return -EFAULT;
2071 return 0;
2072 }
2073
2074
2075 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
2076 {
2077 struct sock *sk;
2078 struct hlist_node *node;
2079 struct net_device *dev = data;
2080 struct net *net = dev_net(dev);
2081
2082 rcu_read_lock();
2083 sk_for_each_rcu(sk, node, &net->packet.sklist) {
2084 struct packet_sock *po = pkt_sk(sk);
2085
2086 switch (msg) {
2087 case NETDEV_UNREGISTER:
2088 if (po->mclist)
2089 packet_dev_mclist(dev, po->mclist, -1);
2090 /* fallthrough */
2091
2092 case NETDEV_DOWN:
2093 if (dev->ifindex == po->ifindex) {
2094 spin_lock(&po->bind_lock);
2095 if (po->running) {
2096 __dev_remove_pack(&po->prot_hook);
2097 __sock_put(sk);
2098 po->running = 0;
2099 sk->sk_err = ENETDOWN;
2100 if (!sock_flag(sk, SOCK_DEAD))
2101 sk->sk_error_report(sk);
2102 }
2103 if (msg == NETDEV_UNREGISTER) {
2104 po->ifindex = -1;
2105 po->prot_hook.dev = NULL;
2106 }
2107 spin_unlock(&po->bind_lock);
2108 }
2109 break;
2110 case NETDEV_UP:
2111 if (dev->ifindex == po->ifindex) {
2112 spin_lock(&po->bind_lock);
2113 if (po->num && !po->running) {
2114 dev_add_pack(&po->prot_hook);
2115 sock_hold(sk);
2116 po->running = 1;
2117 }
2118 spin_unlock(&po->bind_lock);
2119 }
2120 break;
2121 }
2122 }
2123 rcu_read_unlock();
2124 return NOTIFY_DONE;
2125 }
2126
2127
2128 static int packet_ioctl(struct socket *sock, unsigned int cmd,
2129 unsigned long arg)
2130 {
2131 struct sock *sk = sock->sk;
2132
2133 switch (cmd) {
2134 case SIOCOUTQ:
2135 {
2136 int amount = sk_wmem_alloc_get(sk);
2137
2138 return put_user(amount, (int __user *)arg);
2139 }
2140 case SIOCINQ:
2141 {
2142 struct sk_buff *skb;
2143 int amount = 0;
2144
2145 spin_lock_bh(&sk->sk_receive_queue.lock);
2146 skb = skb_peek(&sk->sk_receive_queue);
2147 if (skb)
2148 amount = skb->len;
2149 spin_unlock_bh(&sk->sk_receive_queue.lock);
2150 return put_user(amount, (int __user *)arg);
2151 }
2152 case SIOCGSTAMP:
2153 return sock_get_timestamp(sk, (struct timeval __user *)arg);
2154 case SIOCGSTAMPNS:
2155 return sock_get_timestampns(sk, (struct timespec __user *)arg);
2156
2157 #ifdef CONFIG_INET
2158 case SIOCADDRT:
2159 case SIOCDELRT:
2160 case SIOCDARP:
2161 case SIOCGARP:
2162 case SIOCSARP:
2163 case SIOCGIFADDR:
2164 case SIOCSIFADDR:
2165 case SIOCGIFBRDADDR:
2166 case SIOCSIFBRDADDR:
2167 case SIOCGIFNETMASK:
2168 case SIOCSIFNETMASK:
2169 case SIOCGIFDSTADDR:
2170 case SIOCSIFDSTADDR:
2171 case SIOCSIFFLAGS:
2172 return inet_dgram_ops.ioctl(sock, cmd, arg);
2173 #endif
2174
2175 default:
2176 return -ENOIOCTLCMD;
2177 }
2178 return 0;
2179 }
2180
2181 static unsigned int packet_poll(struct file *file, struct socket *sock,
2182 poll_table *wait)
2183 {
2184 struct sock *sk = sock->sk;
2185 struct packet_sock *po = pkt_sk(sk);
2186 unsigned int mask = datagram_poll(file, sock, wait);
2187
2188 spin_lock_bh(&sk->sk_receive_queue.lock);
2189 if (po->rx_ring.pg_vec) {
2190 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
2191 mask |= POLLIN | POLLRDNORM;
2192 }
2193 spin_unlock_bh(&sk->sk_receive_queue.lock);
2194 spin_lock_bh(&sk->sk_write_queue.lock);
2195 if (po->tx_ring.pg_vec) {
2196 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
2197 mask |= POLLOUT | POLLWRNORM;
2198 }
2199 spin_unlock_bh(&sk->sk_write_queue.lock);
2200 return mask;
2201 }
2202
2203
2204 /* Dirty? Well, I still did not learn better way to account
2205 * for user mmaps.
2206 */
2207
2208 static void packet_mm_open(struct vm_area_struct *vma)
2209 {
2210 struct file *file = vma->vm_file;
2211 struct socket *sock = file->private_data;
2212 struct sock *sk = sock->sk;
2213
2214 if (sk)
2215 atomic_inc(&pkt_sk(sk)->mapped);
2216 }
2217
2218 static void packet_mm_close(struct vm_area_struct *vma)
2219 {
2220 struct file *file = vma->vm_file;
2221 struct socket *sock = file->private_data;
2222 struct sock *sk = sock->sk;
2223
2224 if (sk)
2225 atomic_dec(&pkt_sk(sk)->mapped);
2226 }
2227
2228 static const struct vm_operations_struct packet_mmap_ops = {
2229 .open = packet_mm_open,
2230 .close = packet_mm_close,
2231 };
2232
2233 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
2234 {
2235 int i;
2236
2237 for (i = 0; i < len; i++) {
2238 if (likely(pg_vec[i]))
2239 free_pages((unsigned long) pg_vec[i], order);
2240 }
2241 kfree(pg_vec);
2242 }
2243
2244 static inline char *alloc_one_pg_vec_page(unsigned long order)
2245 {
2246 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | __GFP_ZERO | __GFP_NOWARN;
2247
2248 return (char *) __get_free_pages(gfp_flags, order);
2249 }
2250
2251 static char **alloc_pg_vec(struct tpacket_req *req, int order)
2252 {
2253 unsigned int block_nr = req->tp_block_nr;
2254 char **pg_vec;
2255 int i;
2256
2257 pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
2258 if (unlikely(!pg_vec))
2259 goto out;
2260
2261 for (i = 0; i < block_nr; i++) {
2262 pg_vec[i] = alloc_one_pg_vec_page(order);
2263 if (unlikely(!pg_vec[i]))
2264 goto out_free_pgvec;
2265 }
2266
2267 out:
2268 return pg_vec;
2269
2270 out_free_pgvec:
2271 free_pg_vec(pg_vec, order, block_nr);
2272 pg_vec = NULL;
2273 goto out;
2274 }
2275
2276 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
2277 int closing, int tx_ring)
2278 {
2279 char **pg_vec = NULL;
2280 struct packet_sock *po = pkt_sk(sk);
2281 int was_running, order = 0;
2282 struct packet_ring_buffer *rb;
2283 struct sk_buff_head *rb_queue;
2284 __be16 num;
2285 int err;
2286
2287 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
2288 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
2289
2290 err = -EBUSY;
2291 if (!closing) {
2292 if (atomic_read(&po->mapped))
2293 goto out;
2294 if (atomic_read(&rb->pending))
2295 goto out;
2296 }
2297
2298 if (req->tp_block_nr) {
2299 /* Sanity tests and some calculations */
2300 err = -EBUSY;
2301 if (unlikely(rb->pg_vec))
2302 goto out;
2303
2304 switch (po->tp_version) {
2305 case TPACKET_V1:
2306 po->tp_hdrlen = TPACKET_HDRLEN;
2307 break;
2308 case TPACKET_V2:
2309 po->tp_hdrlen = TPACKET2_HDRLEN;
2310 break;
2311 }
2312
2313 err = -EINVAL;
2314 if (unlikely((int)req->tp_block_size <= 0))
2315 goto out;
2316 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
2317 goto out;
2318 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
2319 po->tp_reserve))
2320 goto out;
2321 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
2322 goto out;
2323
2324 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
2325 if (unlikely(rb->frames_per_block <= 0))
2326 goto out;
2327 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
2328 req->tp_frame_nr))
2329 goto out;
2330
2331 err = -ENOMEM;
2332 order = get_order(req->tp_block_size);
2333 pg_vec = alloc_pg_vec(req, order);
2334 if (unlikely(!pg_vec))
2335 goto out;
2336 }
2337 /* Done */
2338 else {
2339 err = -EINVAL;
2340 if (unlikely(req->tp_frame_nr))
2341 goto out;
2342 }
2343
2344 lock_sock(sk);
2345
2346 /* Detach socket from network */
2347 spin_lock(&po->bind_lock);
2348 was_running = po->running;
2349 num = po->num;
2350 if (was_running) {
2351 __dev_remove_pack(&po->prot_hook);
2352 po->num = 0;
2353 po->running = 0;
2354 __sock_put(sk);
2355 }
2356 spin_unlock(&po->bind_lock);
2357
2358 synchronize_net();
2359
2360 err = -EBUSY;
2361 mutex_lock(&po->pg_vec_lock);
2362 if (closing || atomic_read(&po->mapped) == 0) {
2363 err = 0;
2364 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
2365 spin_lock_bh(&rb_queue->lock);
2366 pg_vec = XC(rb->pg_vec, pg_vec);
2367 rb->frame_max = (req->tp_frame_nr - 1);
2368 rb->head = 0;
2369 rb->frame_size = req->tp_frame_size;
2370 spin_unlock_bh(&rb_queue->lock);
2371
2372 order = XC(rb->pg_vec_order, order);
2373 req->tp_block_nr = XC(rb->pg_vec_len, req->tp_block_nr);
2374
2375 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
2376 po->prot_hook.func = (po->rx_ring.pg_vec) ?
2377 tpacket_rcv : packet_rcv;
2378 skb_queue_purge(rb_queue);
2379 #undef XC
2380 if (atomic_read(&po->mapped))
2381 pr_err("packet_mmap: vma is busy: %d\n",
2382 atomic_read(&po->mapped));
2383 }
2384 mutex_unlock(&po->pg_vec_lock);
2385
2386 spin_lock(&po->bind_lock);
2387 if (was_running && !po->running) {
2388 sock_hold(sk);
2389 po->running = 1;
2390 po->num = num;
2391 dev_add_pack(&po->prot_hook);
2392 }
2393 spin_unlock(&po->bind_lock);
2394
2395 release_sock(sk);
2396
2397 if (pg_vec)
2398 free_pg_vec(pg_vec, order, req->tp_block_nr);
2399 out:
2400 return err;
2401 }
2402
2403 static int packet_mmap(struct file *file, struct socket *sock,
2404 struct vm_area_struct *vma)
2405 {
2406 struct sock *sk = sock->sk;
2407 struct packet_sock *po = pkt_sk(sk);
2408 unsigned long size, expected_size;
2409 struct packet_ring_buffer *rb;
2410 unsigned long start;
2411 int err = -EINVAL;
2412 int i;
2413
2414 if (vma->vm_pgoff)
2415 return -EINVAL;
2416
2417 mutex_lock(&po->pg_vec_lock);
2418
2419 expected_size = 0;
2420 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2421 if (rb->pg_vec) {
2422 expected_size += rb->pg_vec_len
2423 * rb->pg_vec_pages
2424 * PAGE_SIZE;
2425 }
2426 }
2427
2428 if (expected_size == 0)
2429 goto out;
2430
2431 size = vma->vm_end - vma->vm_start;
2432 if (size != expected_size)
2433 goto out;
2434
2435 start = vma->vm_start;
2436 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2437 if (rb->pg_vec == NULL)
2438 continue;
2439
2440 for (i = 0; i < rb->pg_vec_len; i++) {
2441 struct page *page = virt_to_page(rb->pg_vec[i]);
2442 int pg_num;
2443
2444 for (pg_num = 0; pg_num < rb->pg_vec_pages;
2445 pg_num++, page++) {
2446 err = vm_insert_page(vma, start, page);
2447 if (unlikely(err))
2448 goto out;
2449 start += PAGE_SIZE;
2450 }
2451 }
2452 }
2453
2454 atomic_inc(&po->mapped);
2455 vma->vm_ops = &packet_mmap_ops;
2456 err = 0;
2457
2458 out:
2459 mutex_unlock(&po->pg_vec_lock);
2460 return err;
2461 }
2462
2463 static const struct proto_ops packet_ops_spkt = {
2464 .family = PF_PACKET,
2465 .owner = THIS_MODULE,
2466 .release = packet_release,
2467 .bind = packet_bind_spkt,
2468 .connect = sock_no_connect,
2469 .socketpair = sock_no_socketpair,
2470 .accept = sock_no_accept,
2471 .getname = packet_getname_spkt,
2472 .poll = datagram_poll,
2473 .ioctl = packet_ioctl,
2474 .listen = sock_no_listen,
2475 .shutdown = sock_no_shutdown,
2476 .setsockopt = sock_no_setsockopt,
2477 .getsockopt = sock_no_getsockopt,
2478 .sendmsg = packet_sendmsg_spkt,
2479 .recvmsg = packet_recvmsg,
2480 .mmap = sock_no_mmap,
2481 .sendpage = sock_no_sendpage,
2482 };
2483
2484 static const struct proto_ops packet_ops = {
2485 .family = PF_PACKET,
2486 .owner = THIS_MODULE,
2487 .release = packet_release,
2488 .bind = packet_bind,
2489 .connect = sock_no_connect,
2490 .socketpair = sock_no_socketpair,
2491 .accept = sock_no_accept,
2492 .getname = packet_getname,
2493 .poll = packet_poll,
2494 .ioctl = packet_ioctl,
2495 .listen = sock_no_listen,
2496 .shutdown = sock_no_shutdown,
2497 .setsockopt = packet_setsockopt,
2498 .getsockopt = packet_getsockopt,
2499 .sendmsg = packet_sendmsg,
2500 .recvmsg = packet_recvmsg,
2501 .mmap = packet_mmap,
2502 .sendpage = sock_no_sendpage,
2503 };
2504
2505 static const struct net_proto_family packet_family_ops = {
2506 .family = PF_PACKET,
2507 .create = packet_create,
2508 .owner = THIS_MODULE,
2509 };
2510
2511 static struct notifier_block packet_netdev_notifier = {
2512 .notifier_call = packet_notifier,
2513 };
2514
2515 #ifdef CONFIG_PROC_FS
2516
2517 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2518 __acquires(RCU)
2519 {
2520 struct net *net = seq_file_net(seq);
2521
2522 rcu_read_lock();
2523 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
2524 }
2525
2526 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2527 {
2528 struct net *net = seq_file_net(seq);
2529 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
2530 }
2531
2532 static void packet_seq_stop(struct seq_file *seq, void *v)
2533 __releases(RCU)
2534 {
2535 rcu_read_unlock();
2536 }
2537
2538 static int packet_seq_show(struct seq_file *seq, void *v)
2539 {
2540 if (v == SEQ_START_TOKEN)
2541 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
2542 else {
2543 struct sock *s = sk_entry(v);
2544 const struct packet_sock *po = pkt_sk(s);
2545
2546 seq_printf(seq,
2547 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
2548 s,
2549 atomic_read(&s->sk_refcnt),
2550 s->sk_type,
2551 ntohs(po->num),
2552 po->ifindex,
2553 po->running,
2554 atomic_read(&s->sk_rmem_alloc),
2555 sock_i_uid(s),
2556 sock_i_ino(s));
2557 }
2558
2559 return 0;
2560 }
2561
2562 static const struct seq_operations packet_seq_ops = {
2563 .start = packet_seq_start,
2564 .next = packet_seq_next,
2565 .stop = packet_seq_stop,
2566 .show = packet_seq_show,
2567 };
2568
2569 static int packet_seq_open(struct inode *inode, struct file *file)
2570 {
2571 return seq_open_net(inode, file, &packet_seq_ops,
2572 sizeof(struct seq_net_private));
2573 }
2574
2575 static const struct file_operations packet_seq_fops = {
2576 .owner = THIS_MODULE,
2577 .open = packet_seq_open,
2578 .read = seq_read,
2579 .llseek = seq_lseek,
2580 .release = seq_release_net,
2581 };
2582
2583 #endif
2584
2585 static int __net_init packet_net_init(struct net *net)
2586 {
2587 spin_lock_init(&net->packet.sklist_lock);
2588 INIT_HLIST_HEAD(&net->packet.sklist);
2589
2590 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
2591 return -ENOMEM;
2592
2593 return 0;
2594 }
2595
2596 static void __net_exit packet_net_exit(struct net *net)
2597 {
2598 proc_net_remove(net, "packet");
2599 }
2600
2601 static struct pernet_operations packet_net_ops = {
2602 .init = packet_net_init,
2603 .exit = packet_net_exit,
2604 };
2605
2606
2607 static void __exit packet_exit(void)
2608 {
2609 unregister_netdevice_notifier(&packet_netdev_notifier);
2610 unregister_pernet_subsys(&packet_net_ops);
2611 sock_unregister(PF_PACKET);
2612 proto_unregister(&packet_proto);
2613 }
2614
2615 static int __init packet_init(void)
2616 {
2617 int rc = proto_register(&packet_proto, 0);
2618
2619 if (rc != 0)
2620 goto out;
2621
2622 sock_register(&packet_family_ops);
2623 register_pernet_subsys(&packet_net_ops);
2624 register_netdevice_notifier(&packet_netdev_notifier);
2625 out:
2626 return rc;
2627 }
2628
2629 module_init(packet_init);
2630 module_exit(packet_exit);
2631 MODULE_LICENSE("GPL");
2632 MODULE_ALIAS_NETPROTO(PF_PACKET);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree