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Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6
[deliverable/linux.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 *
43 * This program is free software; you can redistribute it and/or
44 * modify it under the terms of the GNU General Public License
45 * as published by the Free Software Foundation; either version
46 * 2 of the License, or (at your option) any later version.
47 *
48 */
49
50 #include <linux/types.h>
51 #include <linux/mm.h>
52 #include <linux/capability.h>
53 #include <linux/fcntl.h>
54 #include <linux/socket.h>
55 #include <linux/in.h>
56 #include <linux/inet.h>
57 #include <linux/netdevice.h>
58 #include <linux/if_packet.h>
59 #include <linux/wireless.h>
60 #include <linux/kernel.h>
61 #include <linux/kmod.h>
62 #include <net/net_namespace.h>
63 #include <net/ip.h>
64 #include <net/protocol.h>
65 #include <linux/skbuff.h>
66 #include <net/sock.h>
67 #include <linux/errno.h>
68 #include <linux/timer.h>
69 #include <asm/system.h>
70 #include <asm/uaccess.h>
71 #include <asm/ioctls.h>
72 #include <asm/page.h>
73 #include <asm/cacheflush.h>
74 #include <asm/io.h>
75 #include <linux/proc_fs.h>
76 #include <linux/seq_file.h>
77 #include <linux/poll.h>
78 #include <linux/module.h>
79 #include <linux/init.h>
80 #include <linux/mutex.h>
81
82 #ifdef CONFIG_INET
83 #include <net/inet_common.h>
84 #endif
85
86 /*
87 Assumptions:
88 - if device has no dev->hard_header routine, it adds and removes ll header
89 inside itself. In this case ll header is invisible outside of device,
90 but higher levels still should reserve dev->hard_header_len.
91 Some devices are enough clever to reallocate skb, when header
92 will not fit to reserved space (tunnel), another ones are silly
93 (PPP).
94 - packet socket receives packets with pulled ll header,
95 so that SOCK_RAW should push it back.
96
97 On receive:
98 -----------
99
100 Incoming, dev->hard_header!=NULL
101 mac_header -> ll header
102 data -> data
103
104 Outgoing, dev->hard_header!=NULL
105 mac_header -> ll header
106 data -> ll header
107
108 Incoming, dev->hard_header==NULL
109 mac_header -> UNKNOWN position. It is very likely, that it points to ll
110 header. PPP makes it, that is wrong, because introduce
111 assymetry between rx and tx paths.
112 data -> data
113
114 Outgoing, dev->hard_header==NULL
115 mac_header -> data. ll header is still not built!
116 data -> data
117
118 Resume
119 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
120
121
122 On transmit:
123 ------------
124
125 dev->hard_header != NULL
126 mac_header -> ll header
127 data -> ll header
128
129 dev->hard_header == NULL (ll header is added by device, we cannot control it)
130 mac_header -> data
131 data -> data
132
133 We should set nh.raw on output to correct posistion,
134 packet classifier depends on it.
135 */
136
137 /* Private packet socket structures. */
138
139 struct packet_mclist
140 {
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 {
153 int mr_ifindex;
154 unsigned short mr_type;
155 unsigned short mr_alen;
156 unsigned char mr_address[MAX_ADDR_LEN];
157 };
158
159 #ifdef CONFIG_PACKET_MMAP
160 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
161 #endif
162
163 static void packet_flush_mclist(struct sock *sk);
164
165 struct packet_sock {
166 /* struct sock has to be the first member of packet_sock */
167 struct sock sk;
168 struct tpacket_stats stats;
169 #ifdef CONFIG_PACKET_MMAP
170 char * *pg_vec;
171 unsigned int head;
172 unsigned int frames_per_block;
173 unsigned int frame_size;
174 unsigned int frame_max;
175 int copy_thresh;
176 #endif
177 struct packet_type prot_hook;
178 spinlock_t bind_lock;
179 struct mutex pg_vec_lock;
180 unsigned int running:1, /* prot_hook is attached*/
181 auxdata:1,
182 origdev:1;
183 int ifindex; /* bound device */
184 __be16 num;
185 struct packet_mclist *mclist;
186 #ifdef CONFIG_PACKET_MMAP
187 atomic_t mapped;
188 unsigned int pg_vec_order;
189 unsigned int pg_vec_pages;
190 unsigned int pg_vec_len;
191 enum tpacket_versions tp_version;
192 unsigned int tp_hdrlen;
193 unsigned int tp_reserve;
194 #endif
195 };
196
197 struct packet_skb_cb {
198 unsigned int origlen;
199 union {
200 struct sockaddr_pkt pkt;
201 struct sockaddr_ll ll;
202 } sa;
203 };
204
205 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
206
207 #ifdef CONFIG_PACKET_MMAP
208
209 static void *packet_lookup_frame(struct packet_sock *po, unsigned int position,
210 int status)
211 {
212 unsigned int pg_vec_pos, frame_offset;
213 union {
214 struct tpacket_hdr *h1;
215 struct tpacket2_hdr *h2;
216 void *raw;
217 } h;
218
219 pg_vec_pos = position / po->frames_per_block;
220 frame_offset = position % po->frames_per_block;
221
222 h.raw = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
223 switch (po->tp_version) {
224 case TPACKET_V1:
225 if (status != h.h1->tp_status ? TP_STATUS_USER :
226 TP_STATUS_KERNEL)
227 return NULL;
228 break;
229 case TPACKET_V2:
230 if (status != h.h2->tp_status ? TP_STATUS_USER :
231 TP_STATUS_KERNEL)
232 return NULL;
233 break;
234 }
235 return h.raw;
236 }
237
238 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
239 {
240 union {
241 struct tpacket_hdr *h1;
242 struct tpacket2_hdr *h2;
243 void *raw;
244 } h;
245
246 h.raw = frame;
247 switch (po->tp_version) {
248 case TPACKET_V1:
249 h.h1->tp_status = status;
250 break;
251 case TPACKET_V2:
252 h.h2->tp_status = status;
253 break;
254 }
255 }
256 #endif
257
258 static inline struct packet_sock *pkt_sk(struct sock *sk)
259 {
260 return (struct packet_sock *)sk;
261 }
262
263 static void packet_sock_destruct(struct sock *sk)
264 {
265 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
266 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
267
268 if (!sock_flag(sk, SOCK_DEAD)) {
269 printk("Attempt to release alive packet socket: %p\n", sk);
270 return;
271 }
272
273 sk_refcnt_debug_dec(sk);
274 }
275
276
277 static const struct proto_ops packet_ops;
278
279 static const struct proto_ops packet_ops_spkt;
280
281 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
282 {
283 struct sock *sk;
284 struct sockaddr_pkt *spkt;
285
286 /*
287 * When we registered the protocol we saved the socket in the data
288 * field for just this event.
289 */
290
291 sk = pt->af_packet_priv;
292
293 /*
294 * Yank back the headers [hope the device set this
295 * right or kerboom...]
296 *
297 * Incoming packets have ll header pulled,
298 * push it back.
299 *
300 * For outgoing ones skb->data == skb_mac_header(skb)
301 * so that this procedure is noop.
302 */
303
304 if (skb->pkt_type == PACKET_LOOPBACK)
305 goto out;
306
307 if (dev_net(dev) != sock_net(sk))
308 goto out;
309
310 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
311 goto oom;
312
313 /* drop any routing info */
314 dst_release(skb->dst);
315 skb->dst = NULL;
316
317 /* drop conntrack reference */
318 nf_reset(skb);
319
320 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
321
322 skb_push(skb, skb->data - skb_mac_header(skb));
323
324 /*
325 * The SOCK_PACKET socket receives _all_ frames.
326 */
327
328 spkt->spkt_family = dev->type;
329 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
330 spkt->spkt_protocol = skb->protocol;
331
332 /*
333 * Charge the memory to the socket. This is done specifically
334 * to prevent sockets using all the memory up.
335 */
336
337 if (sock_queue_rcv_skb(sk,skb) == 0)
338 return 0;
339
340 out:
341 kfree_skb(skb);
342 oom:
343 return 0;
344 }
345
346
347 /*
348 * Output a raw packet to a device layer. This bypasses all the other
349 * protocol layers and you must therefore supply it with a complete frame
350 */
351
352 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
353 struct msghdr *msg, size_t len)
354 {
355 struct sock *sk = sock->sk;
356 struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
357 struct sk_buff *skb;
358 struct net_device *dev;
359 __be16 proto=0;
360 int err;
361
362 /*
363 * Get and verify the address.
364 */
365
366 if (saddr)
367 {
368 if (msg->msg_namelen < sizeof(struct sockaddr))
369 return(-EINVAL);
370 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
371 proto=saddr->spkt_protocol;
372 }
373 else
374 return(-ENOTCONN); /* SOCK_PACKET must be sent giving an address */
375
376 /*
377 * Find the device first to size check it
378 */
379
380 saddr->spkt_device[13] = 0;
381 dev = dev_get_by_name(sock_net(sk), saddr->spkt_device);
382 err = -ENODEV;
383 if (dev == NULL)
384 goto out_unlock;
385
386 err = -ENETDOWN;
387 if (!(dev->flags & IFF_UP))
388 goto out_unlock;
389
390 /*
391 * You may not queue a frame bigger than the mtu. This is the lowest level
392 * raw protocol and you must do your own fragmentation at this level.
393 */
394
395 err = -EMSGSIZE;
396 if (len > dev->mtu + dev->hard_header_len)
397 goto out_unlock;
398
399 err = -ENOBUFS;
400 skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
401
402 /*
403 * If the write buffer is full, then tough. At this level the user gets to
404 * deal with the problem - do your own algorithmic backoffs. That's far
405 * more flexible.
406 */
407
408 if (skb == NULL)
409 goto out_unlock;
410
411 /*
412 * Fill it in
413 */
414
415 /* FIXME: Save some space for broken drivers that write a
416 * hard header at transmission time by themselves. PPP is the
417 * notable one here. This should really be fixed at the driver level.
418 */
419 skb_reserve(skb, LL_RESERVED_SPACE(dev));
420 skb_reset_network_header(skb);
421
422 /* Try to align data part correctly */
423 if (dev->header_ops) {
424 skb->data -= dev->hard_header_len;
425 skb->tail -= dev->hard_header_len;
426 if (len < dev->hard_header_len)
427 skb_reset_network_header(skb);
428 }
429
430 /* Returns -EFAULT on error */
431 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
432 skb->protocol = proto;
433 skb->dev = dev;
434 skb->priority = sk->sk_priority;
435 if (err)
436 goto out_free;
437
438 /*
439 * Now send it
440 */
441
442 dev_queue_xmit(skb);
443 dev_put(dev);
444 return(len);
445
446 out_free:
447 kfree_skb(skb);
448 out_unlock:
449 if (dev)
450 dev_put(dev);
451 return err;
452 }
453
454 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
455 unsigned int res)
456 {
457 struct sk_filter *filter;
458
459 rcu_read_lock_bh();
460 filter = rcu_dereference(sk->sk_filter);
461 if (filter != NULL)
462 res = sk_run_filter(skb, filter->insns, filter->len);
463 rcu_read_unlock_bh();
464
465 return res;
466 }
467
468 /*
469 This function makes lazy skb cloning in hope that most of packets
470 are discarded by BPF.
471
472 Note tricky part: we DO mangle shared skb! skb->data, skb->len
473 and skb->cb are mangled. It works because (and until) packets
474 falling here are owned by current CPU. Output packets are cloned
475 by dev_queue_xmit_nit(), input packets are processed by net_bh
476 sequencially, so that if we return skb to original state on exit,
477 we will not harm anyone.
478 */
479
480 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
481 {
482 struct sock *sk;
483 struct sockaddr_ll *sll;
484 struct packet_sock *po;
485 u8 * skb_head = skb->data;
486 int skb_len = skb->len;
487 unsigned int snaplen, res;
488
489 if (skb->pkt_type == PACKET_LOOPBACK)
490 goto drop;
491
492 sk = pt->af_packet_priv;
493 po = pkt_sk(sk);
494
495 if (dev_net(dev) != sock_net(sk))
496 goto drop;
497
498 skb->dev = dev;
499
500 if (dev->header_ops) {
501 /* The device has an explicit notion of ll header,
502 exported to higher levels.
503
504 Otherwise, the device hides datails of it frame
505 structure, so that corresponding packet head
506 never delivered to user.
507 */
508 if (sk->sk_type != SOCK_DGRAM)
509 skb_push(skb, skb->data - skb_mac_header(skb));
510 else if (skb->pkt_type == PACKET_OUTGOING) {
511 /* Special case: outgoing packets have ll header at head */
512 skb_pull(skb, skb_network_offset(skb));
513 }
514 }
515
516 snaplen = skb->len;
517
518 res = run_filter(skb, sk, snaplen);
519 if (!res)
520 goto drop_n_restore;
521 if (snaplen > res)
522 snaplen = res;
523
524 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
525 (unsigned)sk->sk_rcvbuf)
526 goto drop_n_acct;
527
528 if (skb_shared(skb)) {
529 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
530 if (nskb == NULL)
531 goto drop_n_acct;
532
533 if (skb_head != skb->data) {
534 skb->data = skb_head;
535 skb->len = skb_len;
536 }
537 kfree_skb(skb);
538 skb = nskb;
539 }
540
541 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
542 sizeof(skb->cb));
543
544 sll = &PACKET_SKB_CB(skb)->sa.ll;
545 sll->sll_family = AF_PACKET;
546 sll->sll_hatype = dev->type;
547 sll->sll_protocol = skb->protocol;
548 sll->sll_pkttype = skb->pkt_type;
549 if (unlikely(po->origdev))
550 sll->sll_ifindex = orig_dev->ifindex;
551 else
552 sll->sll_ifindex = dev->ifindex;
553
554 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
555
556 PACKET_SKB_CB(skb)->origlen = skb->len;
557
558 if (pskb_trim(skb, snaplen))
559 goto drop_n_acct;
560
561 skb_set_owner_r(skb, sk);
562 skb->dev = NULL;
563 dst_release(skb->dst);
564 skb->dst = NULL;
565
566 /* drop conntrack reference */
567 nf_reset(skb);
568
569 spin_lock(&sk->sk_receive_queue.lock);
570 po->stats.tp_packets++;
571 __skb_queue_tail(&sk->sk_receive_queue, skb);
572 spin_unlock(&sk->sk_receive_queue.lock);
573 sk->sk_data_ready(sk, skb->len);
574 return 0;
575
576 drop_n_acct:
577 spin_lock(&sk->sk_receive_queue.lock);
578 po->stats.tp_drops++;
579 spin_unlock(&sk->sk_receive_queue.lock);
580
581 drop_n_restore:
582 if (skb_head != skb->data && skb_shared(skb)) {
583 skb->data = skb_head;
584 skb->len = skb_len;
585 }
586 drop:
587 kfree_skb(skb);
588 return 0;
589 }
590
591 #ifdef CONFIG_PACKET_MMAP
592 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
593 {
594 struct sock *sk;
595 struct packet_sock *po;
596 struct sockaddr_ll *sll;
597 union {
598 struct tpacket_hdr *h1;
599 struct tpacket2_hdr *h2;
600 void *raw;
601 } h;
602 u8 * skb_head = skb->data;
603 int skb_len = skb->len;
604 unsigned int snaplen, res;
605 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
606 unsigned short macoff, netoff, hdrlen;
607 struct sk_buff *copy_skb = NULL;
608 struct timeval tv;
609 struct timespec ts;
610
611 if (skb->pkt_type == PACKET_LOOPBACK)
612 goto drop;
613
614 sk = pt->af_packet_priv;
615 po = pkt_sk(sk);
616
617 if (dev_net(dev) != sock_net(sk))
618 goto drop;
619
620 if (dev->header_ops) {
621 if (sk->sk_type != SOCK_DGRAM)
622 skb_push(skb, skb->data - skb_mac_header(skb));
623 else if (skb->pkt_type == PACKET_OUTGOING) {
624 /* Special case: outgoing packets have ll header at head */
625 skb_pull(skb, skb_network_offset(skb));
626 }
627 }
628
629 if (skb->ip_summed == CHECKSUM_PARTIAL)
630 status |= TP_STATUS_CSUMNOTREADY;
631
632 snaplen = skb->len;
633
634 res = run_filter(skb, sk, snaplen);
635 if (!res)
636 goto drop_n_restore;
637 if (snaplen > res)
638 snaplen = res;
639
640 if (sk->sk_type == SOCK_DGRAM) {
641 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
642 po->tp_reserve;
643 } else {
644 unsigned maclen = skb_network_offset(skb);
645 netoff = TPACKET_ALIGN(po->tp_hdrlen +
646 (maclen < 16 ? 16 : maclen)) +
647 po->tp_reserve;
648 macoff = netoff - maclen;
649 }
650
651 if (macoff + snaplen > po->frame_size) {
652 if (po->copy_thresh &&
653 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
654 (unsigned)sk->sk_rcvbuf) {
655 if (skb_shared(skb)) {
656 copy_skb = skb_clone(skb, GFP_ATOMIC);
657 } else {
658 copy_skb = skb_get(skb);
659 skb_head = skb->data;
660 }
661 if (copy_skb)
662 skb_set_owner_r(copy_skb, sk);
663 }
664 snaplen = po->frame_size - macoff;
665 if ((int)snaplen < 0)
666 snaplen = 0;
667 }
668
669 spin_lock(&sk->sk_receive_queue.lock);
670 h.raw = packet_lookup_frame(po, po->head, TP_STATUS_KERNEL);
671 if (!h.raw)
672 goto ring_is_full;
673 po->head = po->head != po->frame_max ? po->head+1 : 0;
674 po->stats.tp_packets++;
675 if (copy_skb) {
676 status |= TP_STATUS_COPY;
677 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
678 }
679 if (!po->stats.tp_drops)
680 status &= ~TP_STATUS_LOSING;
681 spin_unlock(&sk->sk_receive_queue.lock);
682
683 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
684
685 switch (po->tp_version) {
686 case TPACKET_V1:
687 h.h1->tp_len = skb->len;
688 h.h1->tp_snaplen = snaplen;
689 h.h1->tp_mac = macoff;
690 h.h1->tp_net = netoff;
691 if (skb->tstamp.tv64)
692 tv = ktime_to_timeval(skb->tstamp);
693 else
694 do_gettimeofday(&tv);
695 h.h1->tp_sec = tv.tv_sec;
696 h.h1->tp_usec = tv.tv_usec;
697 hdrlen = sizeof(*h.h1);
698 break;
699 case TPACKET_V2:
700 h.h2->tp_len = skb->len;
701 h.h2->tp_snaplen = snaplen;
702 h.h2->tp_mac = macoff;
703 h.h2->tp_net = netoff;
704 if (skb->tstamp.tv64)
705 ts = ktime_to_timespec(skb->tstamp);
706 else
707 getnstimeofday(&ts);
708 h.h2->tp_sec = ts.tv_sec;
709 h.h2->tp_nsec = ts.tv_nsec;
710 h.h2->tp_vlan_tci = skb->vlan_tci;
711 hdrlen = sizeof(*h.h2);
712 break;
713 default:
714 BUG();
715 }
716
717 sll = h.raw + TPACKET_ALIGN(hdrlen);
718 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
719 sll->sll_family = AF_PACKET;
720 sll->sll_hatype = dev->type;
721 sll->sll_protocol = skb->protocol;
722 sll->sll_pkttype = skb->pkt_type;
723 if (unlikely(po->origdev))
724 sll->sll_ifindex = orig_dev->ifindex;
725 else
726 sll->sll_ifindex = dev->ifindex;
727
728 __packet_set_status(po, h.raw, status);
729 smp_mb();
730
731 {
732 struct page *p_start, *p_end;
733 u8 *h_end = h.raw + macoff + snaplen - 1;
734
735 p_start = virt_to_page(h.raw);
736 p_end = virt_to_page(h_end);
737 while (p_start <= p_end) {
738 flush_dcache_page(p_start);
739 p_start++;
740 }
741 }
742
743 sk->sk_data_ready(sk, 0);
744
745 drop_n_restore:
746 if (skb_head != skb->data && skb_shared(skb)) {
747 skb->data = skb_head;
748 skb->len = skb_len;
749 }
750 drop:
751 kfree_skb(skb);
752 return 0;
753
754 ring_is_full:
755 po->stats.tp_drops++;
756 spin_unlock(&sk->sk_receive_queue.lock);
757
758 sk->sk_data_ready(sk, 0);
759 if (copy_skb)
760 kfree_skb(copy_skb);
761 goto drop_n_restore;
762 }
763
764 #endif
765
766
767 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
768 struct msghdr *msg, size_t len)
769 {
770 struct sock *sk = sock->sk;
771 struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
772 struct sk_buff *skb;
773 struct net_device *dev;
774 __be16 proto;
775 unsigned char *addr;
776 int ifindex, err, reserve = 0;
777
778 /*
779 * Get and verify the address.
780 */
781
782 if (saddr == NULL) {
783 struct packet_sock *po = pkt_sk(sk);
784
785 ifindex = po->ifindex;
786 proto = po->num;
787 addr = NULL;
788 } else {
789 err = -EINVAL;
790 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
791 goto out;
792 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
793 goto out;
794 ifindex = saddr->sll_ifindex;
795 proto = saddr->sll_protocol;
796 addr = saddr->sll_addr;
797 }
798
799
800 dev = dev_get_by_index(sock_net(sk), ifindex);
801 err = -ENXIO;
802 if (dev == NULL)
803 goto out_unlock;
804 if (sock->type == SOCK_RAW)
805 reserve = dev->hard_header_len;
806
807 err = -ENETDOWN;
808 if (!(dev->flags & IFF_UP))
809 goto out_unlock;
810
811 err = -EMSGSIZE;
812 if (len > dev->mtu+reserve)
813 goto out_unlock;
814
815 skb = sock_alloc_send_skb(sk, len + LL_ALLOCATED_SPACE(dev),
816 msg->msg_flags & MSG_DONTWAIT, &err);
817 if (skb==NULL)
818 goto out_unlock;
819
820 skb_reserve(skb, LL_RESERVED_SPACE(dev));
821 skb_reset_network_header(skb);
822
823 err = -EINVAL;
824 if (sock->type == SOCK_DGRAM &&
825 dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len) < 0)
826 goto out_free;
827
828 /* Returns -EFAULT on error */
829 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
830 if (err)
831 goto out_free;
832
833 skb->protocol = proto;
834 skb->dev = dev;
835 skb->priority = sk->sk_priority;
836
837 /*
838 * Now send it
839 */
840
841 err = dev_queue_xmit(skb);
842 if (err > 0 && (err = net_xmit_errno(err)) != 0)
843 goto out_unlock;
844
845 dev_put(dev);
846
847 return(len);
848
849 out_free:
850 kfree_skb(skb);
851 out_unlock:
852 if (dev)
853 dev_put(dev);
854 out:
855 return err;
856 }
857
858 /*
859 * Close a PACKET socket. This is fairly simple. We immediately go
860 * to 'closed' state and remove our protocol entry in the device list.
861 */
862
863 static int packet_release(struct socket *sock)
864 {
865 struct sock *sk = sock->sk;
866 struct packet_sock *po;
867 struct net *net;
868
869 if (!sk)
870 return 0;
871
872 net = sock_net(sk);
873 po = pkt_sk(sk);
874
875 write_lock_bh(&net->packet.sklist_lock);
876 sk_del_node_init(sk);
877 sock_prot_inuse_add(net, sk->sk_prot, -1);
878 write_unlock_bh(&net->packet.sklist_lock);
879
880 /*
881 * Unhook packet receive handler.
882 */
883
884 if (po->running) {
885 /*
886 * Remove the protocol hook
887 */
888 dev_remove_pack(&po->prot_hook);
889 po->running = 0;
890 po->num = 0;
891 __sock_put(sk);
892 }
893
894 packet_flush_mclist(sk);
895
896 #ifdef CONFIG_PACKET_MMAP
897 if (po->pg_vec) {
898 struct tpacket_req req;
899 memset(&req, 0, sizeof(req));
900 packet_set_ring(sk, &req, 1);
901 }
902 #endif
903
904 /*
905 * Now the socket is dead. No more input will appear.
906 */
907
908 sock_orphan(sk);
909 sock->sk = NULL;
910
911 /* Purge queues */
912
913 skb_queue_purge(&sk->sk_receive_queue);
914 sk_refcnt_debug_release(sk);
915
916 sock_put(sk);
917 return 0;
918 }
919
920 /*
921 * Attach a packet hook.
922 */
923
924 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
925 {
926 struct packet_sock *po = pkt_sk(sk);
927 /*
928 * Detach an existing hook if present.
929 */
930
931 lock_sock(sk);
932
933 spin_lock(&po->bind_lock);
934 if (po->running) {
935 __sock_put(sk);
936 po->running = 0;
937 po->num = 0;
938 spin_unlock(&po->bind_lock);
939 dev_remove_pack(&po->prot_hook);
940 spin_lock(&po->bind_lock);
941 }
942
943 po->num = protocol;
944 po->prot_hook.type = protocol;
945 po->prot_hook.dev = dev;
946
947 po->ifindex = dev ? dev->ifindex : 0;
948
949 if (protocol == 0)
950 goto out_unlock;
951
952 if (!dev || (dev->flags & IFF_UP)) {
953 dev_add_pack(&po->prot_hook);
954 sock_hold(sk);
955 po->running = 1;
956 } else {
957 sk->sk_err = ENETDOWN;
958 if (!sock_flag(sk, SOCK_DEAD))
959 sk->sk_error_report(sk);
960 }
961
962 out_unlock:
963 spin_unlock(&po->bind_lock);
964 release_sock(sk);
965 return 0;
966 }
967
968 /*
969 * Bind a packet socket to a device
970 */
971
972 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
973 {
974 struct sock *sk=sock->sk;
975 char name[15];
976 struct net_device *dev;
977 int err = -ENODEV;
978
979 /*
980 * Check legality
981 */
982
983 if (addr_len != sizeof(struct sockaddr))
984 return -EINVAL;
985 strlcpy(name,uaddr->sa_data,sizeof(name));
986
987 dev = dev_get_by_name(sock_net(sk), name);
988 if (dev) {
989 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
990 dev_put(dev);
991 }
992 return err;
993 }
994
995 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
996 {
997 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
998 struct sock *sk=sock->sk;
999 struct net_device *dev = NULL;
1000 int err;
1001
1002
1003 /*
1004 * Check legality
1005 */
1006
1007 if (addr_len < sizeof(struct sockaddr_ll))
1008 return -EINVAL;
1009 if (sll->sll_family != AF_PACKET)
1010 return -EINVAL;
1011
1012 if (sll->sll_ifindex) {
1013 err = -ENODEV;
1014 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1015 if (dev == NULL)
1016 goto out;
1017 }
1018 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1019 if (dev)
1020 dev_put(dev);
1021
1022 out:
1023 return err;
1024 }
1025
1026 static struct proto packet_proto = {
1027 .name = "PACKET",
1028 .owner = THIS_MODULE,
1029 .obj_size = sizeof(struct packet_sock),
1030 };
1031
1032 /*
1033 * Create a packet of type SOCK_PACKET.
1034 */
1035
1036 static int packet_create(struct net *net, struct socket *sock, int protocol)
1037 {
1038 struct sock *sk;
1039 struct packet_sock *po;
1040 __be16 proto = (__force __be16)protocol; /* weird, but documented */
1041 int err;
1042
1043 if (!capable(CAP_NET_RAW))
1044 return -EPERM;
1045 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1046 sock->type != SOCK_PACKET)
1047 return -ESOCKTNOSUPPORT;
1048
1049 sock->state = SS_UNCONNECTED;
1050
1051 err = -ENOBUFS;
1052 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1053 if (sk == NULL)
1054 goto out;
1055
1056 sock->ops = &packet_ops;
1057 if (sock->type == SOCK_PACKET)
1058 sock->ops = &packet_ops_spkt;
1059
1060 sock_init_data(sock, sk);
1061
1062 po = pkt_sk(sk);
1063 sk->sk_family = PF_PACKET;
1064 po->num = proto;
1065
1066 sk->sk_destruct = packet_sock_destruct;
1067 sk_refcnt_debug_inc(sk);
1068
1069 /*
1070 * Attach a protocol block
1071 */
1072
1073 spin_lock_init(&po->bind_lock);
1074 mutex_init(&po->pg_vec_lock);
1075 po->prot_hook.func = packet_rcv;
1076
1077 if (sock->type == SOCK_PACKET)
1078 po->prot_hook.func = packet_rcv_spkt;
1079
1080 po->prot_hook.af_packet_priv = sk;
1081
1082 if (proto) {
1083 po->prot_hook.type = proto;
1084 dev_add_pack(&po->prot_hook);
1085 sock_hold(sk);
1086 po->running = 1;
1087 }
1088
1089 write_lock_bh(&net->packet.sklist_lock);
1090 sk_add_node(sk, &net->packet.sklist);
1091 sock_prot_inuse_add(net, &packet_proto, 1);
1092 write_unlock_bh(&net->packet.sklist_lock);
1093 return(0);
1094 out:
1095 return err;
1096 }
1097
1098 /*
1099 * Pull a packet from our receive queue and hand it to the user.
1100 * If necessary we block.
1101 */
1102
1103 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1104 struct msghdr *msg, size_t len, int flags)
1105 {
1106 struct sock *sk = sock->sk;
1107 struct sk_buff *skb;
1108 int copied, err;
1109 struct sockaddr_ll *sll;
1110
1111 err = -EINVAL;
1112 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1113 goto out;
1114
1115 #if 0
1116 /* What error should we return now? EUNATTACH? */
1117 if (pkt_sk(sk)->ifindex < 0)
1118 return -ENODEV;
1119 #endif
1120
1121 /*
1122 * Call the generic datagram receiver. This handles all sorts
1123 * of horrible races and re-entrancy so we can forget about it
1124 * in the protocol layers.
1125 *
1126 * Now it will return ENETDOWN, if device have just gone down,
1127 * but then it will block.
1128 */
1129
1130 skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1131
1132 /*
1133 * An error occurred so return it. Because skb_recv_datagram()
1134 * handles the blocking we don't see and worry about blocking
1135 * retries.
1136 */
1137
1138 if (skb == NULL)
1139 goto out;
1140
1141 /*
1142 * If the address length field is there to be filled in, we fill
1143 * it in now.
1144 */
1145
1146 sll = &PACKET_SKB_CB(skb)->sa.ll;
1147 if (sock->type == SOCK_PACKET)
1148 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1149 else
1150 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1151
1152 /*
1153 * You lose any data beyond the buffer you gave. If it worries a
1154 * user program they can ask the device for its MTU anyway.
1155 */
1156
1157 copied = skb->len;
1158 if (copied > len)
1159 {
1160 copied=len;
1161 msg->msg_flags|=MSG_TRUNC;
1162 }
1163
1164 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1165 if (err)
1166 goto out_free;
1167
1168 sock_recv_timestamp(msg, sk, skb);
1169
1170 if (msg->msg_name)
1171 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1172 msg->msg_namelen);
1173
1174 if (pkt_sk(sk)->auxdata) {
1175 struct tpacket_auxdata aux;
1176
1177 aux.tp_status = TP_STATUS_USER;
1178 if (skb->ip_summed == CHECKSUM_PARTIAL)
1179 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1180 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1181 aux.tp_snaplen = skb->len;
1182 aux.tp_mac = 0;
1183 aux.tp_net = skb_network_offset(skb);
1184 aux.tp_vlan_tci = skb->vlan_tci;
1185
1186 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1187 }
1188
1189 /*
1190 * Free or return the buffer as appropriate. Again this
1191 * hides all the races and re-entrancy issues from us.
1192 */
1193 err = (flags&MSG_TRUNC) ? skb->len : copied;
1194
1195 out_free:
1196 skb_free_datagram(sk, skb);
1197 out:
1198 return err;
1199 }
1200
1201 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1202 int *uaddr_len, int peer)
1203 {
1204 struct net_device *dev;
1205 struct sock *sk = sock->sk;
1206
1207 if (peer)
1208 return -EOPNOTSUPP;
1209
1210 uaddr->sa_family = AF_PACKET;
1211 dev = dev_get_by_index(sock_net(sk), pkt_sk(sk)->ifindex);
1212 if (dev) {
1213 strlcpy(uaddr->sa_data, dev->name, 15);
1214 dev_put(dev);
1215 } else
1216 memset(uaddr->sa_data, 0, 14);
1217 *uaddr_len = sizeof(*uaddr);
1218
1219 return 0;
1220 }
1221
1222 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1223 int *uaddr_len, int peer)
1224 {
1225 struct net_device *dev;
1226 struct sock *sk = sock->sk;
1227 struct packet_sock *po = pkt_sk(sk);
1228 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1229
1230 if (peer)
1231 return -EOPNOTSUPP;
1232
1233 sll->sll_family = AF_PACKET;
1234 sll->sll_ifindex = po->ifindex;
1235 sll->sll_protocol = po->num;
1236 dev = dev_get_by_index(sock_net(sk), po->ifindex);
1237 if (dev) {
1238 sll->sll_hatype = dev->type;
1239 sll->sll_halen = dev->addr_len;
1240 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1241 dev_put(dev);
1242 } else {
1243 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
1244 sll->sll_halen = 0;
1245 }
1246 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1247
1248 return 0;
1249 }
1250
1251 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
1252 int what)
1253 {
1254 switch (i->type) {
1255 case PACKET_MR_MULTICAST:
1256 if (what > 0)
1257 dev_mc_add(dev, i->addr, i->alen, 0);
1258 else
1259 dev_mc_delete(dev, i->addr, i->alen, 0);
1260 break;
1261 case PACKET_MR_PROMISC:
1262 return dev_set_promiscuity(dev, what);
1263 break;
1264 case PACKET_MR_ALLMULTI:
1265 return dev_set_allmulti(dev, what);
1266 break;
1267 default:;
1268 }
1269 return 0;
1270 }
1271
1272 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1273 {
1274 for ( ; i; i=i->next) {
1275 if (i->ifindex == dev->ifindex)
1276 packet_dev_mc(dev, i, what);
1277 }
1278 }
1279
1280 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1281 {
1282 struct packet_sock *po = pkt_sk(sk);
1283 struct packet_mclist *ml, *i;
1284 struct net_device *dev;
1285 int err;
1286
1287 rtnl_lock();
1288
1289 err = -ENODEV;
1290 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
1291 if (!dev)
1292 goto done;
1293
1294 err = -EINVAL;
1295 if (mreq->mr_alen > dev->addr_len)
1296 goto done;
1297
1298 err = -ENOBUFS;
1299 i = kmalloc(sizeof(*i), GFP_KERNEL);
1300 if (i == NULL)
1301 goto done;
1302
1303 err = 0;
1304 for (ml = po->mclist; ml; ml = ml->next) {
1305 if (ml->ifindex == mreq->mr_ifindex &&
1306 ml->type == mreq->mr_type &&
1307 ml->alen == mreq->mr_alen &&
1308 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1309 ml->count++;
1310 /* Free the new element ... */
1311 kfree(i);
1312 goto done;
1313 }
1314 }
1315
1316 i->type = mreq->mr_type;
1317 i->ifindex = mreq->mr_ifindex;
1318 i->alen = mreq->mr_alen;
1319 memcpy(i->addr, mreq->mr_address, i->alen);
1320 i->count = 1;
1321 i->next = po->mclist;
1322 po->mclist = i;
1323 err = packet_dev_mc(dev, i, 1);
1324 if (err) {
1325 po->mclist = i->next;
1326 kfree(i);
1327 }
1328
1329 done:
1330 rtnl_unlock();
1331 return err;
1332 }
1333
1334 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1335 {
1336 struct packet_mclist *ml, **mlp;
1337
1338 rtnl_lock();
1339
1340 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1341 if (ml->ifindex == mreq->mr_ifindex &&
1342 ml->type == mreq->mr_type &&
1343 ml->alen == mreq->mr_alen &&
1344 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1345 if (--ml->count == 0) {
1346 struct net_device *dev;
1347 *mlp = ml->next;
1348 dev = dev_get_by_index(sock_net(sk), ml->ifindex);
1349 if (dev) {
1350 packet_dev_mc(dev, ml, -1);
1351 dev_put(dev);
1352 }
1353 kfree(ml);
1354 }
1355 rtnl_unlock();
1356 return 0;
1357 }
1358 }
1359 rtnl_unlock();
1360 return -EADDRNOTAVAIL;
1361 }
1362
1363 static void packet_flush_mclist(struct sock *sk)
1364 {
1365 struct packet_sock *po = pkt_sk(sk);
1366 struct packet_mclist *ml;
1367
1368 if (!po->mclist)
1369 return;
1370
1371 rtnl_lock();
1372 while ((ml = po->mclist) != NULL) {
1373 struct net_device *dev;
1374
1375 po->mclist = ml->next;
1376 if ((dev = dev_get_by_index(sock_net(sk), ml->ifindex)) != NULL) {
1377 packet_dev_mc(dev, ml, -1);
1378 dev_put(dev);
1379 }
1380 kfree(ml);
1381 }
1382 rtnl_unlock();
1383 }
1384
1385 static int
1386 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1387 {
1388 struct sock *sk = sock->sk;
1389 struct packet_sock *po = pkt_sk(sk);
1390 int ret;
1391
1392 if (level != SOL_PACKET)
1393 return -ENOPROTOOPT;
1394
1395 switch(optname) {
1396 case PACKET_ADD_MEMBERSHIP:
1397 case PACKET_DROP_MEMBERSHIP:
1398 {
1399 struct packet_mreq_max mreq;
1400 int len = optlen;
1401 memset(&mreq, 0, sizeof(mreq));
1402 if (len < sizeof(struct packet_mreq))
1403 return -EINVAL;
1404 if (len > sizeof(mreq))
1405 len = sizeof(mreq);
1406 if (copy_from_user(&mreq,optval,len))
1407 return -EFAULT;
1408 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1409 return -EINVAL;
1410 if (optname == PACKET_ADD_MEMBERSHIP)
1411 ret = packet_mc_add(sk, &mreq);
1412 else
1413 ret = packet_mc_drop(sk, &mreq);
1414 return ret;
1415 }
1416
1417 #ifdef CONFIG_PACKET_MMAP
1418 case PACKET_RX_RING:
1419 {
1420 struct tpacket_req req;
1421
1422 if (optlen<sizeof(req))
1423 return -EINVAL;
1424 if (copy_from_user(&req,optval,sizeof(req)))
1425 return -EFAULT;
1426 return packet_set_ring(sk, &req, 0);
1427 }
1428 case PACKET_COPY_THRESH:
1429 {
1430 int val;
1431
1432 if (optlen!=sizeof(val))
1433 return -EINVAL;
1434 if (copy_from_user(&val,optval,sizeof(val)))
1435 return -EFAULT;
1436
1437 pkt_sk(sk)->copy_thresh = val;
1438 return 0;
1439 }
1440 case PACKET_VERSION:
1441 {
1442 int val;
1443
1444 if (optlen != sizeof(val))
1445 return -EINVAL;
1446 if (po->pg_vec)
1447 return -EBUSY;
1448 if (copy_from_user(&val, optval, sizeof(val)))
1449 return -EFAULT;
1450 switch (val) {
1451 case TPACKET_V1:
1452 case TPACKET_V2:
1453 po->tp_version = val;
1454 return 0;
1455 default:
1456 return -EINVAL;
1457 }
1458 }
1459 case PACKET_RESERVE:
1460 {
1461 unsigned int val;
1462
1463 if (optlen != sizeof(val))
1464 return -EINVAL;
1465 if (po->pg_vec)
1466 return -EBUSY;
1467 if (copy_from_user(&val, optval, sizeof(val)))
1468 return -EFAULT;
1469 po->tp_reserve = val;
1470 return 0;
1471 }
1472 #endif
1473 case PACKET_AUXDATA:
1474 {
1475 int val;
1476
1477 if (optlen < sizeof(val))
1478 return -EINVAL;
1479 if (copy_from_user(&val, optval, sizeof(val)))
1480 return -EFAULT;
1481
1482 po->auxdata = !!val;
1483 return 0;
1484 }
1485 case PACKET_ORIGDEV:
1486 {
1487 int val;
1488
1489 if (optlen < sizeof(val))
1490 return -EINVAL;
1491 if (copy_from_user(&val, optval, sizeof(val)))
1492 return -EFAULT;
1493
1494 po->origdev = !!val;
1495 return 0;
1496 }
1497 default:
1498 return -ENOPROTOOPT;
1499 }
1500 }
1501
1502 static int packet_getsockopt(struct socket *sock, int level, int optname,
1503 char __user *optval, int __user *optlen)
1504 {
1505 int len;
1506 int val;
1507 struct sock *sk = sock->sk;
1508 struct packet_sock *po = pkt_sk(sk);
1509 void *data;
1510 struct tpacket_stats st;
1511
1512 if (level != SOL_PACKET)
1513 return -ENOPROTOOPT;
1514
1515 if (get_user(len, optlen))
1516 return -EFAULT;
1517
1518 if (len < 0)
1519 return -EINVAL;
1520
1521 switch(optname) {
1522 case PACKET_STATISTICS:
1523 if (len > sizeof(struct tpacket_stats))
1524 len = sizeof(struct tpacket_stats);
1525 spin_lock_bh(&sk->sk_receive_queue.lock);
1526 st = po->stats;
1527 memset(&po->stats, 0, sizeof(st));
1528 spin_unlock_bh(&sk->sk_receive_queue.lock);
1529 st.tp_packets += st.tp_drops;
1530
1531 data = &st;
1532 break;
1533 case PACKET_AUXDATA:
1534 if (len > sizeof(int))
1535 len = sizeof(int);
1536 val = po->auxdata;
1537
1538 data = &val;
1539 break;
1540 case PACKET_ORIGDEV:
1541 if (len > sizeof(int))
1542 len = sizeof(int);
1543 val = po->origdev;
1544
1545 data = &val;
1546 break;
1547 #ifdef CONFIG_PACKET_MMAP
1548 case PACKET_VERSION:
1549 if (len > sizeof(int))
1550 len = sizeof(int);
1551 val = po->tp_version;
1552 data = &val;
1553 break;
1554 case PACKET_HDRLEN:
1555 if (len > sizeof(int))
1556 len = sizeof(int);
1557 if (copy_from_user(&val, optval, len))
1558 return -EFAULT;
1559 switch (val) {
1560 case TPACKET_V1:
1561 val = sizeof(struct tpacket_hdr);
1562 break;
1563 case TPACKET_V2:
1564 val = sizeof(struct tpacket2_hdr);
1565 break;
1566 default:
1567 return -EINVAL;
1568 }
1569 data = &val;
1570 break;
1571 case PACKET_RESERVE:
1572 if (len > sizeof(unsigned int))
1573 len = sizeof(unsigned int);
1574 val = po->tp_reserve;
1575 data = &val;
1576 break;
1577 #endif
1578 default:
1579 return -ENOPROTOOPT;
1580 }
1581
1582 if (put_user(len, optlen))
1583 return -EFAULT;
1584 if (copy_to_user(optval, data, len))
1585 return -EFAULT;
1586 return 0;
1587 }
1588
1589
1590 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1591 {
1592 struct sock *sk;
1593 struct hlist_node *node;
1594 struct net_device *dev = data;
1595 struct net *net = dev_net(dev);
1596
1597 read_lock(&net->packet.sklist_lock);
1598 sk_for_each(sk, node, &net->packet.sklist) {
1599 struct packet_sock *po = pkt_sk(sk);
1600
1601 switch (msg) {
1602 case NETDEV_UNREGISTER:
1603 if (po->mclist)
1604 packet_dev_mclist(dev, po->mclist, -1);
1605 /* fallthrough */
1606
1607 case NETDEV_DOWN:
1608 if (dev->ifindex == po->ifindex) {
1609 spin_lock(&po->bind_lock);
1610 if (po->running) {
1611 __dev_remove_pack(&po->prot_hook);
1612 __sock_put(sk);
1613 po->running = 0;
1614 sk->sk_err = ENETDOWN;
1615 if (!sock_flag(sk, SOCK_DEAD))
1616 sk->sk_error_report(sk);
1617 }
1618 if (msg == NETDEV_UNREGISTER) {
1619 po->ifindex = -1;
1620 po->prot_hook.dev = NULL;
1621 }
1622 spin_unlock(&po->bind_lock);
1623 }
1624 break;
1625 case NETDEV_UP:
1626 spin_lock(&po->bind_lock);
1627 if (dev->ifindex == po->ifindex && po->num &&
1628 !po->running) {
1629 dev_add_pack(&po->prot_hook);
1630 sock_hold(sk);
1631 po->running = 1;
1632 }
1633 spin_unlock(&po->bind_lock);
1634 break;
1635 }
1636 }
1637 read_unlock(&net->packet.sklist_lock);
1638 return NOTIFY_DONE;
1639 }
1640
1641
1642 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1643 unsigned long arg)
1644 {
1645 struct sock *sk = sock->sk;
1646
1647 switch(cmd) {
1648 case SIOCOUTQ:
1649 {
1650 int amount = atomic_read(&sk->sk_wmem_alloc);
1651 return put_user(amount, (int __user *)arg);
1652 }
1653 case SIOCINQ:
1654 {
1655 struct sk_buff *skb;
1656 int amount = 0;
1657
1658 spin_lock_bh(&sk->sk_receive_queue.lock);
1659 skb = skb_peek(&sk->sk_receive_queue);
1660 if (skb)
1661 amount = skb->len;
1662 spin_unlock_bh(&sk->sk_receive_queue.lock);
1663 return put_user(amount, (int __user *)arg);
1664 }
1665 case SIOCGSTAMP:
1666 return sock_get_timestamp(sk, (struct timeval __user *)arg);
1667 case SIOCGSTAMPNS:
1668 return sock_get_timestampns(sk, (struct timespec __user *)arg);
1669
1670 #ifdef CONFIG_INET
1671 case SIOCADDRT:
1672 case SIOCDELRT:
1673 case SIOCDARP:
1674 case SIOCGARP:
1675 case SIOCSARP:
1676 case SIOCGIFADDR:
1677 case SIOCSIFADDR:
1678 case SIOCGIFBRDADDR:
1679 case SIOCSIFBRDADDR:
1680 case SIOCGIFNETMASK:
1681 case SIOCSIFNETMASK:
1682 case SIOCGIFDSTADDR:
1683 case SIOCSIFDSTADDR:
1684 case SIOCSIFFLAGS:
1685 if (!net_eq(sock_net(sk), &init_net))
1686 return -ENOIOCTLCMD;
1687 return inet_dgram_ops.ioctl(sock, cmd, arg);
1688 #endif
1689
1690 default:
1691 return -ENOIOCTLCMD;
1692 }
1693 return 0;
1694 }
1695
1696 #ifndef CONFIG_PACKET_MMAP
1697 #define packet_mmap sock_no_mmap
1698 #define packet_poll datagram_poll
1699 #else
1700
1701 static unsigned int packet_poll(struct file * file, struct socket *sock,
1702 poll_table *wait)
1703 {
1704 struct sock *sk = sock->sk;
1705 struct packet_sock *po = pkt_sk(sk);
1706 unsigned int mask = datagram_poll(file, sock, wait);
1707
1708 spin_lock_bh(&sk->sk_receive_queue.lock);
1709 if (po->pg_vec) {
1710 unsigned last = po->head ? po->head-1 : po->frame_max;
1711
1712 if (packet_lookup_frame(po, last, TP_STATUS_USER))
1713 mask |= POLLIN | POLLRDNORM;
1714 }
1715 spin_unlock_bh(&sk->sk_receive_queue.lock);
1716 return mask;
1717 }
1718
1719
1720 /* Dirty? Well, I still did not learn better way to account
1721 * for user mmaps.
1722 */
1723
1724 static void packet_mm_open(struct vm_area_struct *vma)
1725 {
1726 struct file *file = vma->vm_file;
1727 struct socket * sock = file->private_data;
1728 struct sock *sk = sock->sk;
1729
1730 if (sk)
1731 atomic_inc(&pkt_sk(sk)->mapped);
1732 }
1733
1734 static void packet_mm_close(struct vm_area_struct *vma)
1735 {
1736 struct file *file = vma->vm_file;
1737 struct socket * sock = file->private_data;
1738 struct sock *sk = sock->sk;
1739
1740 if (sk)
1741 atomic_dec(&pkt_sk(sk)->mapped);
1742 }
1743
1744 static struct vm_operations_struct packet_mmap_ops = {
1745 .open = packet_mm_open,
1746 .close =packet_mm_close,
1747 };
1748
1749 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
1750 {
1751 int i;
1752
1753 for (i = 0; i < len; i++) {
1754 if (likely(pg_vec[i]))
1755 free_pages((unsigned long) pg_vec[i], order);
1756 }
1757 kfree(pg_vec);
1758 }
1759
1760 static inline char *alloc_one_pg_vec_page(unsigned long order)
1761 {
1762 return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
1763 order);
1764 }
1765
1766 static char **alloc_pg_vec(struct tpacket_req *req, int order)
1767 {
1768 unsigned int block_nr = req->tp_block_nr;
1769 char **pg_vec;
1770 int i;
1771
1772 pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
1773 if (unlikely(!pg_vec))
1774 goto out;
1775
1776 for (i = 0; i < block_nr; i++) {
1777 pg_vec[i] = alloc_one_pg_vec_page(order);
1778 if (unlikely(!pg_vec[i]))
1779 goto out_free_pgvec;
1780 }
1781
1782 out:
1783 return pg_vec;
1784
1785 out_free_pgvec:
1786 free_pg_vec(pg_vec, order, block_nr);
1787 pg_vec = NULL;
1788 goto out;
1789 }
1790
1791 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1792 {
1793 char **pg_vec = NULL;
1794 struct packet_sock *po = pkt_sk(sk);
1795 int was_running, order = 0;
1796 __be16 num;
1797 int err = 0;
1798
1799 if (req->tp_block_nr) {
1800 int i;
1801
1802 /* Sanity tests and some calculations */
1803
1804 if (unlikely(po->pg_vec))
1805 return -EBUSY;
1806
1807 switch (po->tp_version) {
1808 case TPACKET_V1:
1809 po->tp_hdrlen = TPACKET_HDRLEN;
1810 break;
1811 case TPACKET_V2:
1812 po->tp_hdrlen = TPACKET2_HDRLEN;
1813 break;
1814 }
1815
1816 if (unlikely((int)req->tp_block_size <= 0))
1817 return -EINVAL;
1818 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
1819 return -EINVAL;
1820 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
1821 po->tp_reserve))
1822 return -EINVAL;
1823 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
1824 return -EINVAL;
1825
1826 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1827 if (unlikely(po->frames_per_block <= 0))
1828 return -EINVAL;
1829 if (unlikely((po->frames_per_block * req->tp_block_nr) !=
1830 req->tp_frame_nr))
1831 return -EINVAL;
1832
1833 err = -ENOMEM;
1834 order = get_order(req->tp_block_size);
1835 pg_vec = alloc_pg_vec(req, order);
1836 if (unlikely(!pg_vec))
1837 goto out;
1838
1839 for (i = 0; i < req->tp_block_nr; i++) {
1840 void *ptr = pg_vec[i];
1841 int k;
1842
1843 for (k = 0; k < po->frames_per_block; k++) {
1844 __packet_set_status(po, ptr, TP_STATUS_KERNEL);
1845 ptr += req->tp_frame_size;
1846 }
1847 }
1848 /* Done */
1849 } else {
1850 if (unlikely(req->tp_frame_nr))
1851 return -EINVAL;
1852 }
1853
1854 lock_sock(sk);
1855
1856 /* Detach socket from network */
1857 spin_lock(&po->bind_lock);
1858 was_running = po->running;
1859 num = po->num;
1860 if (was_running) {
1861 __dev_remove_pack(&po->prot_hook);
1862 po->num = 0;
1863 po->running = 0;
1864 __sock_put(sk);
1865 }
1866 spin_unlock(&po->bind_lock);
1867
1868 synchronize_net();
1869
1870 err = -EBUSY;
1871 mutex_lock(&po->pg_vec_lock);
1872 if (closing || atomic_read(&po->mapped) == 0) {
1873 err = 0;
1874 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1875
1876 spin_lock_bh(&sk->sk_receive_queue.lock);
1877 pg_vec = XC(po->pg_vec, pg_vec);
1878 po->frame_max = (req->tp_frame_nr - 1);
1879 po->head = 0;
1880 po->frame_size = req->tp_frame_size;
1881 spin_unlock_bh(&sk->sk_receive_queue.lock);
1882
1883 order = XC(po->pg_vec_order, order);
1884 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1885
1886 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1887 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1888 skb_queue_purge(&sk->sk_receive_queue);
1889 #undef XC
1890 if (atomic_read(&po->mapped))
1891 printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1892 }
1893 mutex_unlock(&po->pg_vec_lock);
1894
1895 spin_lock(&po->bind_lock);
1896 if (was_running && !po->running) {
1897 sock_hold(sk);
1898 po->running = 1;
1899 po->num = num;
1900 dev_add_pack(&po->prot_hook);
1901 }
1902 spin_unlock(&po->bind_lock);
1903
1904 release_sock(sk);
1905
1906 if (pg_vec)
1907 free_pg_vec(pg_vec, order, req->tp_block_nr);
1908 out:
1909 return err;
1910 }
1911
1912 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1913 {
1914 struct sock *sk = sock->sk;
1915 struct packet_sock *po = pkt_sk(sk);
1916 unsigned long size;
1917 unsigned long start;
1918 int err = -EINVAL;
1919 int i;
1920
1921 if (vma->vm_pgoff)
1922 return -EINVAL;
1923
1924 size = vma->vm_end - vma->vm_start;
1925
1926 mutex_lock(&po->pg_vec_lock);
1927 if (po->pg_vec == NULL)
1928 goto out;
1929 if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1930 goto out;
1931
1932 start = vma->vm_start;
1933 for (i = 0; i < po->pg_vec_len; i++) {
1934 struct page *page = virt_to_page(po->pg_vec[i]);
1935 int pg_num;
1936
1937 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
1938 err = vm_insert_page(vma, start, page);
1939 if (unlikely(err))
1940 goto out;
1941 start += PAGE_SIZE;
1942 }
1943 }
1944 atomic_inc(&po->mapped);
1945 vma->vm_ops = &packet_mmap_ops;
1946 err = 0;
1947
1948 out:
1949 mutex_unlock(&po->pg_vec_lock);
1950 return err;
1951 }
1952 #endif
1953
1954
1955 static const struct proto_ops packet_ops_spkt = {
1956 .family = PF_PACKET,
1957 .owner = THIS_MODULE,
1958 .release = packet_release,
1959 .bind = packet_bind_spkt,
1960 .connect = sock_no_connect,
1961 .socketpair = sock_no_socketpair,
1962 .accept = sock_no_accept,
1963 .getname = packet_getname_spkt,
1964 .poll = datagram_poll,
1965 .ioctl = packet_ioctl,
1966 .listen = sock_no_listen,
1967 .shutdown = sock_no_shutdown,
1968 .setsockopt = sock_no_setsockopt,
1969 .getsockopt = sock_no_getsockopt,
1970 .sendmsg = packet_sendmsg_spkt,
1971 .recvmsg = packet_recvmsg,
1972 .mmap = sock_no_mmap,
1973 .sendpage = sock_no_sendpage,
1974 };
1975
1976 static const struct proto_ops packet_ops = {
1977 .family = PF_PACKET,
1978 .owner = THIS_MODULE,
1979 .release = packet_release,
1980 .bind = packet_bind,
1981 .connect = sock_no_connect,
1982 .socketpair = sock_no_socketpair,
1983 .accept = sock_no_accept,
1984 .getname = packet_getname,
1985 .poll = packet_poll,
1986 .ioctl = packet_ioctl,
1987 .listen = sock_no_listen,
1988 .shutdown = sock_no_shutdown,
1989 .setsockopt = packet_setsockopt,
1990 .getsockopt = packet_getsockopt,
1991 .sendmsg = packet_sendmsg,
1992 .recvmsg = packet_recvmsg,
1993 .mmap = packet_mmap,
1994 .sendpage = sock_no_sendpage,
1995 };
1996
1997 static struct net_proto_family packet_family_ops = {
1998 .family = PF_PACKET,
1999 .create = packet_create,
2000 .owner = THIS_MODULE,
2001 };
2002
2003 static struct notifier_block packet_netdev_notifier = {
2004 .notifier_call =packet_notifier,
2005 };
2006
2007 #ifdef CONFIG_PROC_FS
2008 static inline struct sock *packet_seq_idx(struct net *net, loff_t off)
2009 {
2010 struct sock *s;
2011 struct hlist_node *node;
2012
2013 sk_for_each(s, node, &net->packet.sklist) {
2014 if (!off--)
2015 return s;
2016 }
2017 return NULL;
2018 }
2019
2020 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2021 __acquires(seq_file_net(seq)->packet.sklist_lock)
2022 {
2023 struct net *net = seq_file_net(seq);
2024 read_lock(&net->packet.sklist_lock);
2025 return *pos ? packet_seq_idx(net, *pos - 1) : SEQ_START_TOKEN;
2026 }
2027
2028 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2029 {
2030 struct net *net = seq_file_net(seq);
2031 ++*pos;
2032 return (v == SEQ_START_TOKEN)
2033 ? sk_head(&net->packet.sklist)
2034 : sk_next((struct sock*)v) ;
2035 }
2036
2037 static void packet_seq_stop(struct seq_file *seq, void *v)
2038 __releases(seq_file_net(seq)->packet.sklist_lock)
2039 {
2040 struct net *net = seq_file_net(seq);
2041 read_unlock(&net->packet.sklist_lock);
2042 }
2043
2044 static int packet_seq_show(struct seq_file *seq, void *v)
2045 {
2046 if (v == SEQ_START_TOKEN)
2047 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
2048 else {
2049 struct sock *s = v;
2050 const struct packet_sock *po = pkt_sk(s);
2051
2052 seq_printf(seq,
2053 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
2054 s,
2055 atomic_read(&s->sk_refcnt),
2056 s->sk_type,
2057 ntohs(po->num),
2058 po->ifindex,
2059 po->running,
2060 atomic_read(&s->sk_rmem_alloc),
2061 sock_i_uid(s),
2062 sock_i_ino(s) );
2063 }
2064
2065 return 0;
2066 }
2067
2068 static const struct seq_operations packet_seq_ops = {
2069 .start = packet_seq_start,
2070 .next = packet_seq_next,
2071 .stop = packet_seq_stop,
2072 .show = packet_seq_show,
2073 };
2074
2075 static int packet_seq_open(struct inode *inode, struct file *file)
2076 {
2077 return seq_open_net(inode, file, &packet_seq_ops,
2078 sizeof(struct seq_net_private));
2079 }
2080
2081 static const struct file_operations packet_seq_fops = {
2082 .owner = THIS_MODULE,
2083 .open = packet_seq_open,
2084 .read = seq_read,
2085 .llseek = seq_lseek,
2086 .release = seq_release_net,
2087 };
2088
2089 #endif
2090
2091 static int packet_net_init(struct net *net)
2092 {
2093 rwlock_init(&net->packet.sklist_lock);
2094 INIT_HLIST_HEAD(&net->packet.sklist);
2095
2096 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
2097 return -ENOMEM;
2098
2099 return 0;
2100 }
2101
2102 static void packet_net_exit(struct net *net)
2103 {
2104 proc_net_remove(net, "packet");
2105 }
2106
2107 static struct pernet_operations packet_net_ops = {
2108 .init = packet_net_init,
2109 .exit = packet_net_exit,
2110 };
2111
2112
2113 static void __exit packet_exit(void)
2114 {
2115 unregister_netdevice_notifier(&packet_netdev_notifier);
2116 unregister_pernet_subsys(&packet_net_ops);
2117 sock_unregister(PF_PACKET);
2118 proto_unregister(&packet_proto);
2119 }
2120
2121 static int __init packet_init(void)
2122 {
2123 int rc = proto_register(&packet_proto, 0);
2124
2125 if (rc != 0)
2126 goto out;
2127
2128 sock_register(&packet_family_ops);
2129 register_pernet_subsys(&packet_net_ops);
2130 register_netdevice_notifier(&packet_netdev_notifier);
2131 out:
2132 return rc;
2133 }
2134
2135 module_init(packet_init);
2136 module_exit(packet_exit);
2137 MODULE_LICENSE("GPL");
2138 MODULE_ALIAS_NETPROTO(PF_PACKET);
Linux kernel - Deliverables
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