projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
[NET]: Make socket creation namespace safe.
[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 * Version: $Id: af_packet.c,v 1.61 2002/02/08 03:57:19 davem Exp $
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Alan Cox, <gw4pts@gw4pts.ampr.org>
13 *
14 * Fixes:
15 * Alan Cox : verify_area() now used correctly
16 * Alan Cox : new skbuff lists, look ma no backlogs!
17 * Alan Cox : tidied skbuff lists.
18 * Alan Cox : Now uses generic datagram routines I
19 * added. Also fixed the peek/read crash
20 * from all old Linux datagram code.
21 * Alan Cox : Uses the improved datagram code.
22 * Alan Cox : Added NULL's for socket options.
23 * Alan Cox : Re-commented the code.
24 * Alan Cox : Use new kernel side addressing
25 * Rob Janssen : Correct MTU usage.
26 * Dave Platt : Counter leaks caused by incorrect
27 * interrupt locking and some slightly
28 * dubious gcc output. Can you read
29 * compiler: it said _VOLATILE_
30 * Richard Kooijman : Timestamp fixes.
31 * Alan Cox : New buffers. Use sk->mac.raw.
32 * Alan Cox : sendmsg/recvmsg support.
33 * Alan Cox : Protocol setting support
34 * Alexey Kuznetsov : Untied from IPv4 stack.
35 * Cyrus Durgin : Fixed kerneld for kmod.
36 * Michal Ostrowski : Module initialization cleanup.
37 * Ulises Alonso : Frame number limit removal and
38 * packet_set_ring memory leak.
39 * Eric Biederman : Allow for > 8 byte hardware addresses.
40 * The convention is that longer addresses
41 * will simply extend the hardware address
42 * byte arrays at the end of sockaddr_ll
43 * and packet_mreq.
44 *
45 * This program is free software; you can redistribute it and/or
46 * modify it under the terms of the GNU General Public License
47 * as published by the Free Software Foundation; either version
48 * 2 of the License, or (at your option) any later version.
49 *
50 */
51
52 #include <linux/types.h>
53 #include <linux/mm.h>
54 #include <linux/capability.h>
55 #include <linux/fcntl.h>
56 #include <linux/socket.h>
57 #include <linux/in.h>
58 #include <linux/inet.h>
59 #include <linux/netdevice.h>
60 #include <linux/if_packet.h>
61 #include <linux/wireless.h>
62 #include <linux/kernel.h>
63 #include <linux/kmod.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
83 #ifdef CONFIG_INET
84 #include <net/inet_common.h>
85 #endif
86
87 /*
88 Assumptions:
89 - if device has no dev->hard_header routine, it adds and removes ll header
90 inside itself. In this case ll header is invisible outside of device,
91 but higher levels still should reserve dev->hard_header_len.
92 Some devices are enough clever to reallocate skb, when header
93 will not fit to reserved space (tunnel), another ones are silly
94 (PPP).
95 - packet socket receives packets with pulled ll header,
96 so that SOCK_RAW should push it back.
97
98 On receive:
99 -----------
100
101 Incoming, dev->hard_header!=NULL
102 mac_header -> ll header
103 data -> data
104
105 Outgoing, dev->hard_header!=NULL
106 mac_header -> ll header
107 data -> ll header
108
109 Incoming, dev->hard_header==NULL
110 mac_header -> UNKNOWN position. It is very likely, that it points to ll
111 header. PPP makes it, that is wrong, because introduce
112 assymetry between rx and tx paths.
113 data -> data
114
115 Outgoing, dev->hard_header==NULL
116 mac_header -> data. ll header is still not built!
117 data -> data
118
119 Resume
120 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
121
122
123 On transmit:
124 ------------
125
126 dev->hard_header != NULL
127 mac_header -> ll header
128 data -> ll header
129
130 dev->hard_header == NULL (ll header is added by device, we cannot control it)
131 mac_header -> data
132 data -> data
133
134 We should set nh.raw on output to correct posistion,
135 packet classifier depends on it.
136 */
137
138 /* List of all packet sockets. */
139 static HLIST_HEAD(packet_sklist);
140 static DEFINE_RWLOCK(packet_sklist_lock);
141
142 static atomic_t packet_socks_nr;
143
144
145 /* Private packet socket structures. */
146
147 struct packet_mclist
148 {
149 struct packet_mclist *next;
150 int ifindex;
151 int count;
152 unsigned short type;
153 unsigned short alen;
154 unsigned char addr[MAX_ADDR_LEN];
155 };
156 /* identical to struct packet_mreq except it has
157 * a longer address field.
158 */
159 struct packet_mreq_max
160 {
161 int mr_ifindex;
162 unsigned short mr_type;
163 unsigned short mr_alen;
164 unsigned char mr_address[MAX_ADDR_LEN];
165 };
166
167 #ifdef CONFIG_PACKET_MMAP
168 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
169 #endif
170
171 static void packet_flush_mclist(struct sock *sk);
172
173 struct packet_sock {
174 /* struct sock has to be the first member of packet_sock */
175 struct sock sk;
176 struct tpacket_stats stats;
177 #ifdef CONFIG_PACKET_MMAP
178 char * *pg_vec;
179 unsigned int head;
180 unsigned int frames_per_block;
181 unsigned int frame_size;
182 unsigned int frame_max;
183 int copy_thresh;
184 #endif
185 struct packet_type prot_hook;
186 spinlock_t bind_lock;
187 unsigned int running:1, /* prot_hook is attached*/
188 auxdata:1,
189 origdev:1;
190 int ifindex; /* bound device */
191 __be16 num;
192 struct packet_mclist *mclist;
193 #ifdef CONFIG_PACKET_MMAP
194 atomic_t mapped;
195 unsigned int pg_vec_order;
196 unsigned int pg_vec_pages;
197 unsigned int pg_vec_len;
198 #endif
199 };
200
201 struct packet_skb_cb {
202 unsigned int origlen;
203 union {
204 struct sockaddr_pkt pkt;
205 struct sockaddr_ll ll;
206 } sa;
207 };
208
209 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
210
211 #ifdef CONFIG_PACKET_MMAP
212
213 static inline struct tpacket_hdr *packet_lookup_frame(struct packet_sock *po, unsigned int position)
214 {
215 unsigned int pg_vec_pos, frame_offset;
216
217 pg_vec_pos = position / po->frames_per_block;
218 frame_offset = position % po->frames_per_block;
219
220 return (struct tpacket_hdr *)(po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size));
221 }
222 #endif
223
224 static inline struct packet_sock *pkt_sk(struct sock *sk)
225 {
226 return (struct packet_sock *)sk;
227 }
228
229 static void packet_sock_destruct(struct sock *sk)
230 {
231 BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
232 BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
233
234 if (!sock_flag(sk, SOCK_DEAD)) {
235 printk("Attempt to release alive packet socket: %p\n", sk);
236 return;
237 }
238
239 atomic_dec(&packet_socks_nr);
240 #ifdef PACKET_REFCNT_DEBUG
241 printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
242 #endif
243 }
244
245
246 static const struct proto_ops packet_ops;
247
248 static const struct proto_ops packet_ops_spkt;
249
250 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
251 {
252 struct sock *sk;
253 struct sockaddr_pkt *spkt;
254
255 /*
256 * When we registered the protocol we saved the socket in the data
257 * field for just this event.
258 */
259
260 sk = pt->af_packet_priv;
261
262 /*
263 * Yank back the headers [hope the device set this
264 * right or kerboom...]
265 *
266 * Incoming packets have ll header pulled,
267 * push it back.
268 *
269 * For outgoing ones skb->data == skb_mac_header(skb)
270 * so that this procedure is noop.
271 */
272
273 if (skb->pkt_type == PACKET_LOOPBACK)
274 goto out;
275
276 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
277 goto oom;
278
279 /* drop any routing info */
280 dst_release(skb->dst);
281 skb->dst = NULL;
282
283 /* drop conntrack reference */
284 nf_reset(skb);
285
286 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
287
288 skb_push(skb, skb->data - skb_mac_header(skb));
289
290 /*
291 * The SOCK_PACKET socket receives _all_ frames.
292 */
293
294 spkt->spkt_family = dev->type;
295 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
296 spkt->spkt_protocol = skb->protocol;
297
298 /*
299 * Charge the memory to the socket. This is done specifically
300 * to prevent sockets using all the memory up.
301 */
302
303 if (sock_queue_rcv_skb(sk,skb) == 0)
304 return 0;
305
306 out:
307 kfree_skb(skb);
308 oom:
309 return 0;
310 }
311
312
313 /*
314 * Output a raw packet to a device layer. This bypasses all the other
315 * protocol layers and you must therefore supply it with a complete frame
316 */
317
318 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
319 struct msghdr *msg, size_t len)
320 {
321 struct sock *sk = sock->sk;
322 struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
323 struct sk_buff *skb;
324 struct net_device *dev;
325 __be16 proto=0;
326 int err;
327
328 /*
329 * Get and verify the address.
330 */
331
332 if (saddr)
333 {
334 if (msg->msg_namelen < sizeof(struct sockaddr))
335 return(-EINVAL);
336 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
337 proto=saddr->spkt_protocol;
338 }
339 else
340 return(-ENOTCONN); /* SOCK_PACKET must be sent giving an address */
341
342 /*
343 * Find the device first to size check it
344 */
345
346 saddr->spkt_device[13] = 0;
347 dev = dev_get_by_name(saddr->spkt_device);
348 err = -ENODEV;
349 if (dev == NULL)
350 goto out_unlock;
351
352 err = -ENETDOWN;
353 if (!(dev->flags & IFF_UP))
354 goto out_unlock;
355
356 /*
357 * You may not queue a frame bigger than the mtu. This is the lowest level
358 * raw protocol and you must do your own fragmentation at this level.
359 */
360
361 err = -EMSGSIZE;
362 if (len > dev->mtu + dev->hard_header_len)
363 goto out_unlock;
364
365 err = -ENOBUFS;
366 skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
367
368 /*
369 * If the write buffer is full, then tough. At this level the user gets to
370 * deal with the problem - do your own algorithmic backoffs. That's far
371 * more flexible.
372 */
373
374 if (skb == NULL)
375 goto out_unlock;
376
377 /*
378 * Fill it in
379 */
380
381 /* FIXME: Save some space for broken drivers that write a
382 * hard header at transmission time by themselves. PPP is the
383 * notable one here. This should really be fixed at the driver level.
384 */
385 skb_reserve(skb, LL_RESERVED_SPACE(dev));
386 skb_reset_network_header(skb);
387
388 /* Try to align data part correctly */
389 if (dev->hard_header) {
390 skb->data -= dev->hard_header_len;
391 skb->tail -= dev->hard_header_len;
392 if (len < dev->hard_header_len)
393 skb_reset_network_header(skb);
394 }
395
396 /* Returns -EFAULT on error */
397 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
398 skb->protocol = proto;
399 skb->dev = dev;
400 skb->priority = sk->sk_priority;
401 if (err)
402 goto out_free;
403
404 /*
405 * Now send it
406 */
407
408 dev_queue_xmit(skb);
409 dev_put(dev);
410 return(len);
411
412 out_free:
413 kfree_skb(skb);
414 out_unlock:
415 if (dev)
416 dev_put(dev);
417 return err;
418 }
419
420 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
421 unsigned int res)
422 {
423 struct sk_filter *filter;
424
425 rcu_read_lock_bh();
426 filter = rcu_dereference(sk->sk_filter);
427 if (filter != NULL)
428 res = sk_run_filter(skb, filter->insns, filter->len);
429 rcu_read_unlock_bh();
430
431 return res;
432 }
433
434 /*
435 This function makes lazy skb cloning in hope that most of packets
436 are discarded by BPF.
437
438 Note tricky part: we DO mangle shared skb! skb->data, skb->len
439 and skb->cb are mangled. It works because (and until) packets
440 falling here are owned by current CPU. Output packets are cloned
441 by dev_queue_xmit_nit(), input packets are processed by net_bh
442 sequencially, so that if we return skb to original state on exit,
443 we will not harm anyone.
444 */
445
446 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
447 {
448 struct sock *sk;
449 struct sockaddr_ll *sll;
450 struct packet_sock *po;
451 u8 * skb_head = skb->data;
452 int skb_len = skb->len;
453 unsigned int snaplen, res;
454
455 if (skb->pkt_type == PACKET_LOOPBACK)
456 goto drop;
457
458 sk = pt->af_packet_priv;
459 po = pkt_sk(sk);
460
461 skb->dev = dev;
462
463 if (dev->hard_header) {
464 /* The device has an explicit notion of ll header,
465 exported to higher levels.
466
467 Otherwise, the device hides datails of it frame
468 structure, so that corresponding packet head
469 never delivered to user.
470 */
471 if (sk->sk_type != SOCK_DGRAM)
472 skb_push(skb, skb->data - skb_mac_header(skb));
473 else if (skb->pkt_type == PACKET_OUTGOING) {
474 /* Special case: outgoing packets have ll header at head */
475 skb_pull(skb, skb_network_offset(skb));
476 }
477 }
478
479 snaplen = skb->len;
480
481 res = run_filter(skb, sk, snaplen);
482 if (!res)
483 goto drop_n_restore;
484 if (snaplen > res)
485 snaplen = res;
486
487 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
488 (unsigned)sk->sk_rcvbuf)
489 goto drop_n_acct;
490
491 if (skb_shared(skb)) {
492 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
493 if (nskb == NULL)
494 goto drop_n_acct;
495
496 if (skb_head != skb->data) {
497 skb->data = skb_head;
498 skb->len = skb_len;
499 }
500 kfree_skb(skb);
501 skb = nskb;
502 }
503
504 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
505 sizeof(skb->cb));
506
507 sll = &PACKET_SKB_CB(skb)->sa.ll;
508 sll->sll_family = AF_PACKET;
509 sll->sll_hatype = dev->type;
510 sll->sll_protocol = skb->protocol;
511 sll->sll_pkttype = skb->pkt_type;
512 if (unlikely(po->origdev) && skb->pkt_type == PACKET_HOST)
513 sll->sll_ifindex = orig_dev->ifindex;
514 else
515 sll->sll_ifindex = dev->ifindex;
516 sll->sll_halen = 0;
517
518 if (dev->hard_header_parse)
519 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
520
521 PACKET_SKB_CB(skb)->origlen = skb->len;
522
523 if (pskb_trim(skb, snaplen))
524 goto drop_n_acct;
525
526 skb_set_owner_r(skb, sk);
527 skb->dev = NULL;
528 dst_release(skb->dst);
529 skb->dst = NULL;
530
531 /* drop conntrack reference */
532 nf_reset(skb);
533
534 spin_lock(&sk->sk_receive_queue.lock);
535 po->stats.tp_packets++;
536 __skb_queue_tail(&sk->sk_receive_queue, skb);
537 spin_unlock(&sk->sk_receive_queue.lock);
538 sk->sk_data_ready(sk, skb->len);
539 return 0;
540
541 drop_n_acct:
542 spin_lock(&sk->sk_receive_queue.lock);
543 po->stats.tp_drops++;
544 spin_unlock(&sk->sk_receive_queue.lock);
545
546 drop_n_restore:
547 if (skb_head != skb->data && skb_shared(skb)) {
548 skb->data = skb_head;
549 skb->len = skb_len;
550 }
551 drop:
552 kfree_skb(skb);
553 return 0;
554 }
555
556 #ifdef CONFIG_PACKET_MMAP
557 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
558 {
559 struct sock *sk;
560 struct packet_sock *po;
561 struct sockaddr_ll *sll;
562 struct tpacket_hdr *h;
563 u8 * skb_head = skb->data;
564 int skb_len = skb->len;
565 unsigned int snaplen, res;
566 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
567 unsigned short macoff, netoff;
568 struct sk_buff *copy_skb = NULL;
569 struct timeval tv;
570
571 if (skb->pkt_type == PACKET_LOOPBACK)
572 goto drop;
573
574 sk = pt->af_packet_priv;
575 po = pkt_sk(sk);
576
577 if (dev->hard_header) {
578 if (sk->sk_type != SOCK_DGRAM)
579 skb_push(skb, skb->data - skb_mac_header(skb));
580 else if (skb->pkt_type == PACKET_OUTGOING) {
581 /* Special case: outgoing packets have ll header at head */
582 skb_pull(skb, skb_network_offset(skb));
583 }
584 }
585
586 if (skb->ip_summed == CHECKSUM_PARTIAL)
587 status |= TP_STATUS_CSUMNOTREADY;
588
589 snaplen = skb->len;
590
591 res = run_filter(skb, sk, snaplen);
592 if (!res)
593 goto drop_n_restore;
594 if (snaplen > res)
595 snaplen = res;
596
597 if (sk->sk_type == SOCK_DGRAM) {
598 macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
599 } else {
600 unsigned maclen = skb_network_offset(skb);
601 netoff = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
602 macoff = netoff - maclen;
603 }
604
605 if (macoff + snaplen > po->frame_size) {
606 if (po->copy_thresh &&
607 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
608 (unsigned)sk->sk_rcvbuf) {
609 if (skb_shared(skb)) {
610 copy_skb = skb_clone(skb, GFP_ATOMIC);
611 } else {
612 copy_skb = skb_get(skb);
613 skb_head = skb->data;
614 }
615 if (copy_skb)
616 skb_set_owner_r(copy_skb, sk);
617 }
618 snaplen = po->frame_size - macoff;
619 if ((int)snaplen < 0)
620 snaplen = 0;
621 }
622
623 spin_lock(&sk->sk_receive_queue.lock);
624 h = packet_lookup_frame(po, po->head);
625
626 if (h->tp_status)
627 goto ring_is_full;
628 po->head = po->head != po->frame_max ? po->head+1 : 0;
629 po->stats.tp_packets++;
630 if (copy_skb) {
631 status |= TP_STATUS_COPY;
632 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
633 }
634 if (!po->stats.tp_drops)
635 status &= ~TP_STATUS_LOSING;
636 spin_unlock(&sk->sk_receive_queue.lock);
637
638 skb_copy_bits(skb, 0, (u8*)h + macoff, snaplen);
639
640 h->tp_len = skb->len;
641 h->tp_snaplen = snaplen;
642 h->tp_mac = macoff;
643 h->tp_net = netoff;
644 if (skb->tstamp.tv64)
645 tv = ktime_to_timeval(skb->tstamp);
646 else
647 do_gettimeofday(&tv);
648 h->tp_sec = tv.tv_sec;
649 h->tp_usec = tv.tv_usec;
650
651 sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
652 sll->sll_halen = 0;
653 if (dev->hard_header_parse)
654 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
655 sll->sll_family = AF_PACKET;
656 sll->sll_hatype = dev->type;
657 sll->sll_protocol = skb->protocol;
658 sll->sll_pkttype = skb->pkt_type;
659 if (unlikely(po->origdev) && skb->pkt_type == PACKET_HOST)
660 sll->sll_ifindex = orig_dev->ifindex;
661 else
662 sll->sll_ifindex = dev->ifindex;
663
664 h->tp_status = status;
665 smp_mb();
666
667 {
668 struct page *p_start, *p_end;
669 u8 *h_end = (u8 *)h + macoff + snaplen - 1;
670
671 p_start = virt_to_page(h);
672 p_end = virt_to_page(h_end);
673 while (p_start <= p_end) {
674 flush_dcache_page(p_start);
675 p_start++;
676 }
677 }
678
679 sk->sk_data_ready(sk, 0);
680
681 drop_n_restore:
682 if (skb_head != skb->data && skb_shared(skb)) {
683 skb->data = skb_head;
684 skb->len = skb_len;
685 }
686 drop:
687 kfree_skb(skb);
688 return 0;
689
690 ring_is_full:
691 po->stats.tp_drops++;
692 spin_unlock(&sk->sk_receive_queue.lock);
693
694 sk->sk_data_ready(sk, 0);
695 if (copy_skb)
696 kfree_skb(copy_skb);
697 goto drop_n_restore;
698 }
699
700 #endif
701
702
703 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
704 struct msghdr *msg, size_t len)
705 {
706 struct sock *sk = sock->sk;
707 struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
708 struct sk_buff *skb;
709 struct net_device *dev;
710 __be16 proto;
711 unsigned char *addr;
712 int ifindex, err, reserve = 0;
713
714 /*
715 * Get and verify the address.
716 */
717
718 if (saddr == NULL) {
719 struct packet_sock *po = pkt_sk(sk);
720
721 ifindex = po->ifindex;
722 proto = po->num;
723 addr = NULL;
724 } else {
725 err = -EINVAL;
726 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
727 goto out;
728 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
729 goto out;
730 ifindex = saddr->sll_ifindex;
731 proto = saddr->sll_protocol;
732 addr = saddr->sll_addr;
733 }
734
735
736 dev = dev_get_by_index(ifindex);
737 err = -ENXIO;
738 if (dev == NULL)
739 goto out_unlock;
740 if (sock->type == SOCK_RAW)
741 reserve = dev->hard_header_len;
742
743 err = -ENETDOWN;
744 if (!(dev->flags & IFF_UP))
745 goto out_unlock;
746
747 err = -EMSGSIZE;
748 if (len > dev->mtu+reserve)
749 goto out_unlock;
750
751 skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
752 msg->msg_flags & MSG_DONTWAIT, &err);
753 if (skb==NULL)
754 goto out_unlock;
755
756 skb_reserve(skb, LL_RESERVED_SPACE(dev));
757 skb_reset_network_header(skb);
758
759 if (dev->hard_header) {
760 int res;
761 err = -EINVAL;
762 res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
763 if (sock->type != SOCK_DGRAM) {
764 skb_reset_tail_pointer(skb);
765 skb->len = 0;
766 } else if (res < 0)
767 goto out_free;
768 }
769
770 /* Returns -EFAULT on error */
771 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
772 if (err)
773 goto out_free;
774
775 skb->protocol = proto;
776 skb->dev = dev;
777 skb->priority = sk->sk_priority;
778
779 /*
780 * Now send it
781 */
782
783 err = dev_queue_xmit(skb);
784 if (err > 0 && (err = net_xmit_errno(err)) != 0)
785 goto out_unlock;
786
787 dev_put(dev);
788
789 return(len);
790
791 out_free:
792 kfree_skb(skb);
793 out_unlock:
794 if (dev)
795 dev_put(dev);
796 out:
797 return err;
798 }
799
800 /*
801 * Close a PACKET socket. This is fairly simple. We immediately go
802 * to 'closed' state and remove our protocol entry in the device list.
803 */
804
805 static int packet_release(struct socket *sock)
806 {
807 struct sock *sk = sock->sk;
808 struct packet_sock *po;
809
810 if (!sk)
811 return 0;
812
813 po = pkt_sk(sk);
814
815 write_lock_bh(&packet_sklist_lock);
816 sk_del_node_init(sk);
817 write_unlock_bh(&packet_sklist_lock);
818
819 /*
820 * Unhook packet receive handler.
821 */
822
823 if (po->running) {
824 /*
825 * Remove the protocol hook
826 */
827 dev_remove_pack(&po->prot_hook);
828 po->running = 0;
829 po->num = 0;
830 __sock_put(sk);
831 }
832
833 packet_flush_mclist(sk);
834
835 #ifdef CONFIG_PACKET_MMAP
836 if (po->pg_vec) {
837 struct tpacket_req req;
838 memset(&req, 0, sizeof(req));
839 packet_set_ring(sk, &req, 1);
840 }
841 #endif
842
843 /*
844 * Now the socket is dead. No more input will appear.
845 */
846
847 sock_orphan(sk);
848 sock->sk = NULL;
849
850 /* Purge queues */
851
852 skb_queue_purge(&sk->sk_receive_queue);
853
854 sock_put(sk);
855 return 0;
856 }
857
858 /*
859 * Attach a packet hook.
860 */
861
862 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
863 {
864 struct packet_sock *po = pkt_sk(sk);
865 /*
866 * Detach an existing hook if present.
867 */
868
869 lock_sock(sk);
870
871 spin_lock(&po->bind_lock);
872 if (po->running) {
873 __sock_put(sk);
874 po->running = 0;
875 po->num = 0;
876 spin_unlock(&po->bind_lock);
877 dev_remove_pack(&po->prot_hook);
878 spin_lock(&po->bind_lock);
879 }
880
881 po->num = protocol;
882 po->prot_hook.type = protocol;
883 po->prot_hook.dev = dev;
884
885 po->ifindex = dev ? dev->ifindex : 0;
886
887 if (protocol == 0)
888 goto out_unlock;
889
890 if (dev) {
891 if (dev->flags&IFF_UP) {
892 dev_add_pack(&po->prot_hook);
893 sock_hold(sk);
894 po->running = 1;
895 } else {
896 sk->sk_err = ENETDOWN;
897 if (!sock_flag(sk, SOCK_DEAD))
898 sk->sk_error_report(sk);
899 }
900 } else {
901 dev_add_pack(&po->prot_hook);
902 sock_hold(sk);
903 po->running = 1;
904 }
905
906 out_unlock:
907 spin_unlock(&po->bind_lock);
908 release_sock(sk);
909 return 0;
910 }
911
912 /*
913 * Bind a packet socket to a device
914 */
915
916 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
917 {
918 struct sock *sk=sock->sk;
919 char name[15];
920 struct net_device *dev;
921 int err = -ENODEV;
922
923 /*
924 * Check legality
925 */
926
927 if (addr_len != sizeof(struct sockaddr))
928 return -EINVAL;
929 strlcpy(name,uaddr->sa_data,sizeof(name));
930
931 dev = dev_get_by_name(name);
932 if (dev) {
933 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
934 dev_put(dev);
935 }
936 return err;
937 }
938
939 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
940 {
941 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
942 struct sock *sk=sock->sk;
943 struct net_device *dev = NULL;
944 int err;
945
946
947 /*
948 * Check legality
949 */
950
951 if (addr_len < sizeof(struct sockaddr_ll))
952 return -EINVAL;
953 if (sll->sll_family != AF_PACKET)
954 return -EINVAL;
955
956 if (sll->sll_ifindex) {
957 err = -ENODEV;
958 dev = dev_get_by_index(sll->sll_ifindex);
959 if (dev == NULL)
960 goto out;
961 }
962 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
963 if (dev)
964 dev_put(dev);
965
966 out:
967 return err;
968 }
969
970 static struct proto packet_proto = {
971 .name = "PACKET",
972 .owner = THIS_MODULE,
973 .obj_size = sizeof(struct packet_sock),
974 };
975
976 /*
977 * Create a packet of type SOCK_PACKET.
978 */
979
980 static int packet_create(struct net *net, struct socket *sock, int protocol)
981 {
982 struct sock *sk;
983 struct packet_sock *po;
984 __be16 proto = (__force __be16)protocol; /* weird, but documented */
985 int err;
986
987 if (net != &init_net)
988 return -EAFNOSUPPORT;
989
990 if (!capable(CAP_NET_RAW))
991 return -EPERM;
992 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
993 sock->type != SOCK_PACKET)
994 return -ESOCKTNOSUPPORT;
995
996 sock->state = SS_UNCONNECTED;
997
998 err = -ENOBUFS;
999 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, 1);
1000 if (sk == NULL)
1001 goto out;
1002
1003 sock->ops = &packet_ops;
1004 if (sock->type == SOCK_PACKET)
1005 sock->ops = &packet_ops_spkt;
1006
1007 sock_init_data(sock, sk);
1008
1009 po = pkt_sk(sk);
1010 sk->sk_family = PF_PACKET;
1011 po->num = proto;
1012
1013 sk->sk_destruct = packet_sock_destruct;
1014 atomic_inc(&packet_socks_nr);
1015
1016 /*
1017 * Attach a protocol block
1018 */
1019
1020 spin_lock_init(&po->bind_lock);
1021 po->prot_hook.func = packet_rcv;
1022
1023 if (sock->type == SOCK_PACKET)
1024 po->prot_hook.func = packet_rcv_spkt;
1025
1026 po->prot_hook.af_packet_priv = sk;
1027
1028 if (proto) {
1029 po->prot_hook.type = proto;
1030 dev_add_pack(&po->prot_hook);
1031 sock_hold(sk);
1032 po->running = 1;
1033 }
1034
1035 write_lock_bh(&packet_sklist_lock);
1036 sk_add_node(sk, &packet_sklist);
1037 write_unlock_bh(&packet_sklist_lock);
1038 return(0);
1039 out:
1040 return err;
1041 }
1042
1043 /*
1044 * Pull a packet from our receive queue and hand it to the user.
1045 * If necessary we block.
1046 */
1047
1048 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1049 struct msghdr *msg, size_t len, int flags)
1050 {
1051 struct sock *sk = sock->sk;
1052 struct sk_buff *skb;
1053 int copied, err;
1054 struct sockaddr_ll *sll;
1055
1056 err = -EINVAL;
1057 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1058 goto out;
1059
1060 #if 0
1061 /* What error should we return now? EUNATTACH? */
1062 if (pkt_sk(sk)->ifindex < 0)
1063 return -ENODEV;
1064 #endif
1065
1066 /*
1067 * Call the generic datagram receiver. This handles all sorts
1068 * of horrible races and re-entrancy so we can forget about it
1069 * in the protocol layers.
1070 *
1071 * Now it will return ENETDOWN, if device have just gone down,
1072 * but then it will block.
1073 */
1074
1075 skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1076
1077 /*
1078 * An error occurred so return it. Because skb_recv_datagram()
1079 * handles the blocking we don't see and worry about blocking
1080 * retries.
1081 */
1082
1083 if (skb == NULL)
1084 goto out;
1085
1086 /*
1087 * If the address length field is there to be filled in, we fill
1088 * it in now.
1089 */
1090
1091 sll = &PACKET_SKB_CB(skb)->sa.ll;
1092 if (sock->type == SOCK_PACKET)
1093 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1094 else
1095 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1096
1097 /*
1098 * You lose any data beyond the buffer you gave. If it worries a
1099 * user program they can ask the device for its MTU anyway.
1100 */
1101
1102 copied = skb->len;
1103 if (copied > len)
1104 {
1105 copied=len;
1106 msg->msg_flags|=MSG_TRUNC;
1107 }
1108
1109 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1110 if (err)
1111 goto out_free;
1112
1113 sock_recv_timestamp(msg, sk, skb);
1114
1115 if (msg->msg_name)
1116 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1117 msg->msg_namelen);
1118
1119 if (pkt_sk(sk)->auxdata) {
1120 struct tpacket_auxdata aux;
1121
1122 aux.tp_status = TP_STATUS_USER;
1123 if (skb->ip_summed == CHECKSUM_PARTIAL)
1124 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1125 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1126 aux.tp_snaplen = skb->len;
1127 aux.tp_mac = 0;
1128 aux.tp_net = skb_network_offset(skb);
1129
1130 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1131 }
1132
1133 /*
1134 * Free or return the buffer as appropriate. Again this
1135 * hides all the races and re-entrancy issues from us.
1136 */
1137 err = (flags&MSG_TRUNC) ? skb->len : copied;
1138
1139 out_free:
1140 skb_free_datagram(sk, skb);
1141 out:
1142 return err;
1143 }
1144
1145 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1146 int *uaddr_len, int peer)
1147 {
1148 struct net_device *dev;
1149 struct sock *sk = sock->sk;
1150
1151 if (peer)
1152 return -EOPNOTSUPP;
1153
1154 uaddr->sa_family = AF_PACKET;
1155 dev = dev_get_by_index(pkt_sk(sk)->ifindex);
1156 if (dev) {
1157 strlcpy(uaddr->sa_data, dev->name, 15);
1158 dev_put(dev);
1159 } else
1160 memset(uaddr->sa_data, 0, 14);
1161 *uaddr_len = sizeof(*uaddr);
1162
1163 return 0;
1164 }
1165
1166 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1167 int *uaddr_len, int peer)
1168 {
1169 struct net_device *dev;
1170 struct sock *sk = sock->sk;
1171 struct packet_sock *po = pkt_sk(sk);
1172 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1173
1174 if (peer)
1175 return -EOPNOTSUPP;
1176
1177 sll->sll_family = AF_PACKET;
1178 sll->sll_ifindex = po->ifindex;
1179 sll->sll_protocol = po->num;
1180 dev = dev_get_by_index(po->ifindex);
1181 if (dev) {
1182 sll->sll_hatype = dev->type;
1183 sll->sll_halen = dev->addr_len;
1184 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1185 dev_put(dev);
1186 } else {
1187 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
1188 sll->sll_halen = 0;
1189 }
1190 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1191
1192 return 0;
1193 }
1194
1195 static void packet_dev_mc(struct net_device *dev, struct packet_mclist *i, int what)
1196 {
1197 switch (i->type) {
1198 case PACKET_MR_MULTICAST:
1199 if (what > 0)
1200 dev_mc_add(dev, i->addr, i->alen, 0);
1201 else
1202 dev_mc_delete(dev, i->addr, i->alen, 0);
1203 break;
1204 case PACKET_MR_PROMISC:
1205 dev_set_promiscuity(dev, what);
1206 break;
1207 case PACKET_MR_ALLMULTI:
1208 dev_set_allmulti(dev, what);
1209 break;
1210 default:;
1211 }
1212 }
1213
1214 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1215 {
1216 for ( ; i; i=i->next) {
1217 if (i->ifindex == dev->ifindex)
1218 packet_dev_mc(dev, i, what);
1219 }
1220 }
1221
1222 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1223 {
1224 struct packet_sock *po = pkt_sk(sk);
1225 struct packet_mclist *ml, *i;
1226 struct net_device *dev;
1227 int err;
1228
1229 rtnl_lock();
1230
1231 err = -ENODEV;
1232 dev = __dev_get_by_index(mreq->mr_ifindex);
1233 if (!dev)
1234 goto done;
1235
1236 err = -EINVAL;
1237 if (mreq->mr_alen > dev->addr_len)
1238 goto done;
1239
1240 err = -ENOBUFS;
1241 i = kmalloc(sizeof(*i), GFP_KERNEL);
1242 if (i == NULL)
1243 goto done;
1244
1245 err = 0;
1246 for (ml = po->mclist; ml; ml = ml->next) {
1247 if (ml->ifindex == mreq->mr_ifindex &&
1248 ml->type == mreq->mr_type &&
1249 ml->alen == mreq->mr_alen &&
1250 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1251 ml->count++;
1252 /* Free the new element ... */
1253 kfree(i);
1254 goto done;
1255 }
1256 }
1257
1258 i->type = mreq->mr_type;
1259 i->ifindex = mreq->mr_ifindex;
1260 i->alen = mreq->mr_alen;
1261 memcpy(i->addr, mreq->mr_address, i->alen);
1262 i->count = 1;
1263 i->next = po->mclist;
1264 po->mclist = i;
1265 packet_dev_mc(dev, i, +1);
1266
1267 done:
1268 rtnl_unlock();
1269 return err;
1270 }
1271
1272 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1273 {
1274 struct packet_mclist *ml, **mlp;
1275
1276 rtnl_lock();
1277
1278 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1279 if (ml->ifindex == mreq->mr_ifindex &&
1280 ml->type == mreq->mr_type &&
1281 ml->alen == mreq->mr_alen &&
1282 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1283 if (--ml->count == 0) {
1284 struct net_device *dev;
1285 *mlp = ml->next;
1286 dev = dev_get_by_index(ml->ifindex);
1287 if (dev) {
1288 packet_dev_mc(dev, ml, -1);
1289 dev_put(dev);
1290 }
1291 kfree(ml);
1292 }
1293 rtnl_unlock();
1294 return 0;
1295 }
1296 }
1297 rtnl_unlock();
1298 return -EADDRNOTAVAIL;
1299 }
1300
1301 static void packet_flush_mclist(struct sock *sk)
1302 {
1303 struct packet_sock *po = pkt_sk(sk);
1304 struct packet_mclist *ml;
1305
1306 if (!po->mclist)
1307 return;
1308
1309 rtnl_lock();
1310 while ((ml = po->mclist) != NULL) {
1311 struct net_device *dev;
1312
1313 po->mclist = ml->next;
1314 if ((dev = dev_get_by_index(ml->ifindex)) != NULL) {
1315 packet_dev_mc(dev, ml, -1);
1316 dev_put(dev);
1317 }
1318 kfree(ml);
1319 }
1320 rtnl_unlock();
1321 }
1322
1323 static int
1324 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1325 {
1326 struct sock *sk = sock->sk;
1327 struct packet_sock *po = pkt_sk(sk);
1328 int ret;
1329
1330 if (level != SOL_PACKET)
1331 return -ENOPROTOOPT;
1332
1333 switch(optname) {
1334 case PACKET_ADD_MEMBERSHIP:
1335 case PACKET_DROP_MEMBERSHIP:
1336 {
1337 struct packet_mreq_max mreq;
1338 int len = optlen;
1339 memset(&mreq, 0, sizeof(mreq));
1340 if (len < sizeof(struct packet_mreq))
1341 return -EINVAL;
1342 if (len > sizeof(mreq))
1343 len = sizeof(mreq);
1344 if (copy_from_user(&mreq,optval,len))
1345 return -EFAULT;
1346 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1347 return -EINVAL;
1348 if (optname == PACKET_ADD_MEMBERSHIP)
1349 ret = packet_mc_add(sk, &mreq);
1350 else
1351 ret = packet_mc_drop(sk, &mreq);
1352 return ret;
1353 }
1354
1355 #ifdef CONFIG_PACKET_MMAP
1356 case PACKET_RX_RING:
1357 {
1358 struct tpacket_req req;
1359
1360 if (optlen<sizeof(req))
1361 return -EINVAL;
1362 if (copy_from_user(&req,optval,sizeof(req)))
1363 return -EFAULT;
1364 return packet_set_ring(sk, &req, 0);
1365 }
1366 case PACKET_COPY_THRESH:
1367 {
1368 int val;
1369
1370 if (optlen!=sizeof(val))
1371 return -EINVAL;
1372 if (copy_from_user(&val,optval,sizeof(val)))
1373 return -EFAULT;
1374
1375 pkt_sk(sk)->copy_thresh = val;
1376 return 0;
1377 }
1378 #endif
1379 case PACKET_AUXDATA:
1380 {
1381 int val;
1382
1383 if (optlen < sizeof(val))
1384 return -EINVAL;
1385 if (copy_from_user(&val, optval, sizeof(val)))
1386 return -EFAULT;
1387
1388 po->auxdata = !!val;
1389 return 0;
1390 }
1391 case PACKET_ORIGDEV:
1392 {
1393 int val;
1394
1395 if (optlen < sizeof(val))
1396 return -EINVAL;
1397 if (copy_from_user(&val, optval, sizeof(val)))
1398 return -EFAULT;
1399
1400 po->origdev = !!val;
1401 return 0;
1402 }
1403 default:
1404 return -ENOPROTOOPT;
1405 }
1406 }
1407
1408 static int packet_getsockopt(struct socket *sock, int level, int optname,
1409 char __user *optval, int __user *optlen)
1410 {
1411 int len;
1412 int val;
1413 struct sock *sk = sock->sk;
1414 struct packet_sock *po = pkt_sk(sk);
1415 void *data;
1416 struct tpacket_stats st;
1417
1418 if (level != SOL_PACKET)
1419 return -ENOPROTOOPT;
1420
1421 if (get_user(len, optlen))
1422 return -EFAULT;
1423
1424 if (len < 0)
1425 return -EINVAL;
1426
1427 switch(optname) {
1428 case PACKET_STATISTICS:
1429 if (len > sizeof(struct tpacket_stats))
1430 len = sizeof(struct tpacket_stats);
1431 spin_lock_bh(&sk->sk_receive_queue.lock);
1432 st = po->stats;
1433 memset(&po->stats, 0, sizeof(st));
1434 spin_unlock_bh(&sk->sk_receive_queue.lock);
1435 st.tp_packets += st.tp_drops;
1436
1437 data = &st;
1438 break;
1439 case PACKET_AUXDATA:
1440 if (len > sizeof(int))
1441 len = sizeof(int);
1442 val = po->auxdata;
1443
1444 data = &val;
1445 break;
1446 case PACKET_ORIGDEV:
1447 if (len > sizeof(int))
1448 len = sizeof(int);
1449 val = po->origdev;
1450
1451 data = &val;
1452 break;
1453 default:
1454 return -ENOPROTOOPT;
1455 }
1456
1457 if (put_user(len, optlen))
1458 return -EFAULT;
1459 if (copy_to_user(optval, data, len))
1460 return -EFAULT;
1461 return 0;
1462 }
1463
1464
1465 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1466 {
1467 struct sock *sk;
1468 struct hlist_node *node;
1469 struct net_device *dev = data;
1470
1471 read_lock(&packet_sklist_lock);
1472 sk_for_each(sk, node, &packet_sklist) {
1473 struct packet_sock *po = pkt_sk(sk);
1474
1475 switch (msg) {
1476 case NETDEV_UNREGISTER:
1477 if (po->mclist)
1478 packet_dev_mclist(dev, po->mclist, -1);
1479 /* fallthrough */
1480
1481 case NETDEV_DOWN:
1482 if (dev->ifindex == po->ifindex) {
1483 spin_lock(&po->bind_lock);
1484 if (po->running) {
1485 __dev_remove_pack(&po->prot_hook);
1486 __sock_put(sk);
1487 po->running = 0;
1488 sk->sk_err = ENETDOWN;
1489 if (!sock_flag(sk, SOCK_DEAD))
1490 sk->sk_error_report(sk);
1491 }
1492 if (msg == NETDEV_UNREGISTER) {
1493 po->ifindex = -1;
1494 po->prot_hook.dev = NULL;
1495 }
1496 spin_unlock(&po->bind_lock);
1497 }
1498 break;
1499 case NETDEV_UP:
1500 spin_lock(&po->bind_lock);
1501 if (dev->ifindex == po->ifindex && po->num &&
1502 !po->running) {
1503 dev_add_pack(&po->prot_hook);
1504 sock_hold(sk);
1505 po->running = 1;
1506 }
1507 spin_unlock(&po->bind_lock);
1508 break;
1509 }
1510 }
1511 read_unlock(&packet_sklist_lock);
1512 return NOTIFY_DONE;
1513 }
1514
1515
1516 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1517 unsigned long arg)
1518 {
1519 struct sock *sk = sock->sk;
1520
1521 switch(cmd) {
1522 case SIOCOUTQ:
1523 {
1524 int amount = atomic_read(&sk->sk_wmem_alloc);
1525 return put_user(amount, (int __user *)arg);
1526 }
1527 case SIOCINQ:
1528 {
1529 struct sk_buff *skb;
1530 int amount = 0;
1531
1532 spin_lock_bh(&sk->sk_receive_queue.lock);
1533 skb = skb_peek(&sk->sk_receive_queue);
1534 if (skb)
1535 amount = skb->len;
1536 spin_unlock_bh(&sk->sk_receive_queue.lock);
1537 return put_user(amount, (int __user *)arg);
1538 }
1539 case SIOCGSTAMP:
1540 return sock_get_timestamp(sk, (struct timeval __user *)arg);
1541 case SIOCGSTAMPNS:
1542 return sock_get_timestampns(sk, (struct timespec __user *)arg);
1543
1544 #ifdef CONFIG_INET
1545 case SIOCADDRT:
1546 case SIOCDELRT:
1547 case SIOCDARP:
1548 case SIOCGARP:
1549 case SIOCSARP:
1550 case SIOCGIFADDR:
1551 case SIOCSIFADDR:
1552 case SIOCGIFBRDADDR:
1553 case SIOCSIFBRDADDR:
1554 case SIOCGIFNETMASK:
1555 case SIOCSIFNETMASK:
1556 case SIOCGIFDSTADDR:
1557 case SIOCSIFDSTADDR:
1558 case SIOCSIFFLAGS:
1559 return inet_dgram_ops.ioctl(sock, cmd, arg);
1560 #endif
1561
1562 default:
1563 return -ENOIOCTLCMD;
1564 }
1565 return 0;
1566 }
1567
1568 #ifndef CONFIG_PACKET_MMAP
1569 #define packet_mmap sock_no_mmap
1570 #define packet_poll datagram_poll
1571 #else
1572
1573 static unsigned int packet_poll(struct file * file, struct socket *sock,
1574 poll_table *wait)
1575 {
1576 struct sock *sk = sock->sk;
1577 struct packet_sock *po = pkt_sk(sk);
1578 unsigned int mask = datagram_poll(file, sock, wait);
1579
1580 spin_lock_bh(&sk->sk_receive_queue.lock);
1581 if (po->pg_vec) {
1582 unsigned last = po->head ? po->head-1 : po->frame_max;
1583 struct tpacket_hdr *h;
1584
1585 h = packet_lookup_frame(po, last);
1586
1587 if (h->tp_status)
1588 mask |= POLLIN | POLLRDNORM;
1589 }
1590 spin_unlock_bh(&sk->sk_receive_queue.lock);
1591 return mask;
1592 }
1593
1594
1595 /* Dirty? Well, I still did not learn better way to account
1596 * for user mmaps.
1597 */
1598
1599 static void packet_mm_open(struct vm_area_struct *vma)
1600 {
1601 struct file *file = vma->vm_file;
1602 struct socket * sock = file->private_data;
1603 struct sock *sk = sock->sk;
1604
1605 if (sk)
1606 atomic_inc(&pkt_sk(sk)->mapped);
1607 }
1608
1609 static void packet_mm_close(struct vm_area_struct *vma)
1610 {
1611 struct file *file = vma->vm_file;
1612 struct socket * sock = file->private_data;
1613 struct sock *sk = sock->sk;
1614
1615 if (sk)
1616 atomic_dec(&pkt_sk(sk)->mapped);
1617 }
1618
1619 static struct vm_operations_struct packet_mmap_ops = {
1620 .open = packet_mm_open,
1621 .close =packet_mm_close,
1622 };
1623
1624 static inline struct page *pg_vec_endpage(char *one_pg_vec, unsigned int order)
1625 {
1626 return virt_to_page(one_pg_vec + (PAGE_SIZE << order) - 1);
1627 }
1628
1629 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
1630 {
1631 int i;
1632
1633 for (i = 0; i < len; i++) {
1634 if (likely(pg_vec[i]))
1635 free_pages((unsigned long) pg_vec[i], order);
1636 }
1637 kfree(pg_vec);
1638 }
1639
1640 static inline char *alloc_one_pg_vec_page(unsigned long order)
1641 {
1642 return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
1643 order);
1644 }
1645
1646 static char **alloc_pg_vec(struct tpacket_req *req, int order)
1647 {
1648 unsigned int block_nr = req->tp_block_nr;
1649 char **pg_vec;
1650 int i;
1651
1652 pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
1653 if (unlikely(!pg_vec))
1654 goto out;
1655
1656 for (i = 0; i < block_nr; i++) {
1657 pg_vec[i] = alloc_one_pg_vec_page(order);
1658 if (unlikely(!pg_vec[i]))
1659 goto out_free_pgvec;
1660 }
1661
1662 out:
1663 return pg_vec;
1664
1665 out_free_pgvec:
1666 free_pg_vec(pg_vec, order, block_nr);
1667 pg_vec = NULL;
1668 goto out;
1669 }
1670
1671 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1672 {
1673 char **pg_vec = NULL;
1674 struct packet_sock *po = pkt_sk(sk);
1675 int was_running, order = 0;
1676 __be16 num;
1677 int err = 0;
1678
1679 if (req->tp_block_nr) {
1680 int i, l;
1681
1682 /* Sanity tests and some calculations */
1683
1684 if (unlikely(po->pg_vec))
1685 return -EBUSY;
1686
1687 if (unlikely((int)req->tp_block_size <= 0))
1688 return -EINVAL;
1689 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
1690 return -EINVAL;
1691 if (unlikely(req->tp_frame_size < TPACKET_HDRLEN))
1692 return -EINVAL;
1693 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
1694 return -EINVAL;
1695
1696 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1697 if (unlikely(po->frames_per_block <= 0))
1698 return -EINVAL;
1699 if (unlikely((po->frames_per_block * req->tp_block_nr) !=
1700 req->tp_frame_nr))
1701 return -EINVAL;
1702
1703 err = -ENOMEM;
1704 order = get_order(req->tp_block_size);
1705 pg_vec = alloc_pg_vec(req, order);
1706 if (unlikely(!pg_vec))
1707 goto out;
1708
1709 l = 0;
1710 for (i = 0; i < req->tp_block_nr; i++) {
1711 char *ptr = pg_vec[i];
1712 struct tpacket_hdr *header;
1713 int k;
1714
1715 for (k = 0; k < po->frames_per_block; k++) {
1716 header = (struct tpacket_hdr *) ptr;
1717 header->tp_status = TP_STATUS_KERNEL;
1718 ptr += req->tp_frame_size;
1719 }
1720 }
1721 /* Done */
1722 } else {
1723 if (unlikely(req->tp_frame_nr))
1724 return -EINVAL;
1725 }
1726
1727 lock_sock(sk);
1728
1729 /* Detach socket from network */
1730 spin_lock(&po->bind_lock);
1731 was_running = po->running;
1732 num = po->num;
1733 if (was_running) {
1734 __dev_remove_pack(&po->prot_hook);
1735 po->num = 0;
1736 po->running = 0;
1737 __sock_put(sk);
1738 }
1739 spin_unlock(&po->bind_lock);
1740
1741 synchronize_net();
1742
1743 err = -EBUSY;
1744 if (closing || atomic_read(&po->mapped) == 0) {
1745 err = 0;
1746 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1747
1748 spin_lock_bh(&sk->sk_receive_queue.lock);
1749 pg_vec = XC(po->pg_vec, pg_vec);
1750 po->frame_max = (req->tp_frame_nr - 1);
1751 po->head = 0;
1752 po->frame_size = req->tp_frame_size;
1753 spin_unlock_bh(&sk->sk_receive_queue.lock);
1754
1755 order = XC(po->pg_vec_order, order);
1756 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1757
1758 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1759 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1760 skb_queue_purge(&sk->sk_receive_queue);
1761 #undef XC
1762 if (atomic_read(&po->mapped))
1763 printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1764 }
1765
1766 spin_lock(&po->bind_lock);
1767 if (was_running && !po->running) {
1768 sock_hold(sk);
1769 po->running = 1;
1770 po->num = num;
1771 dev_add_pack(&po->prot_hook);
1772 }
1773 spin_unlock(&po->bind_lock);
1774
1775 release_sock(sk);
1776
1777 if (pg_vec)
1778 free_pg_vec(pg_vec, order, req->tp_block_nr);
1779 out:
1780 return err;
1781 }
1782
1783 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1784 {
1785 struct sock *sk = sock->sk;
1786 struct packet_sock *po = pkt_sk(sk);
1787 unsigned long size;
1788 unsigned long start;
1789 int err = -EINVAL;
1790 int i;
1791
1792 if (vma->vm_pgoff)
1793 return -EINVAL;
1794
1795 size = vma->vm_end - vma->vm_start;
1796
1797 lock_sock(sk);
1798 if (po->pg_vec == NULL)
1799 goto out;
1800 if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1801 goto out;
1802
1803 start = vma->vm_start;
1804 for (i = 0; i < po->pg_vec_len; i++) {
1805 struct page *page = virt_to_page(po->pg_vec[i]);
1806 int pg_num;
1807
1808 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
1809 err = vm_insert_page(vma, start, page);
1810 if (unlikely(err))
1811 goto out;
1812 start += PAGE_SIZE;
1813 }
1814 }
1815 atomic_inc(&po->mapped);
1816 vma->vm_ops = &packet_mmap_ops;
1817 err = 0;
1818
1819 out:
1820 release_sock(sk);
1821 return err;
1822 }
1823 #endif
1824
1825
1826 static const struct proto_ops packet_ops_spkt = {
1827 .family = PF_PACKET,
1828 .owner = THIS_MODULE,
1829 .release = packet_release,
1830 .bind = packet_bind_spkt,
1831 .connect = sock_no_connect,
1832 .socketpair = sock_no_socketpair,
1833 .accept = sock_no_accept,
1834 .getname = packet_getname_spkt,
1835 .poll = datagram_poll,
1836 .ioctl = packet_ioctl,
1837 .listen = sock_no_listen,
1838 .shutdown = sock_no_shutdown,
1839 .setsockopt = sock_no_setsockopt,
1840 .getsockopt = sock_no_getsockopt,
1841 .sendmsg = packet_sendmsg_spkt,
1842 .recvmsg = packet_recvmsg,
1843 .mmap = sock_no_mmap,
1844 .sendpage = sock_no_sendpage,
1845 };
1846
1847 static const struct proto_ops packet_ops = {
1848 .family = PF_PACKET,
1849 .owner = THIS_MODULE,
1850 .release = packet_release,
1851 .bind = packet_bind,
1852 .connect = sock_no_connect,
1853 .socketpair = sock_no_socketpair,
1854 .accept = sock_no_accept,
1855 .getname = packet_getname,
1856 .poll = packet_poll,
1857 .ioctl = packet_ioctl,
1858 .listen = sock_no_listen,
1859 .shutdown = sock_no_shutdown,
1860 .setsockopt = packet_setsockopt,
1861 .getsockopt = packet_getsockopt,
1862 .sendmsg = packet_sendmsg,
1863 .recvmsg = packet_recvmsg,
1864 .mmap = packet_mmap,
1865 .sendpage = sock_no_sendpage,
1866 };
1867
1868 static struct net_proto_family packet_family_ops = {
1869 .family = PF_PACKET,
1870 .create = packet_create,
1871 .owner = THIS_MODULE,
1872 };
1873
1874 static struct notifier_block packet_netdev_notifier = {
1875 .notifier_call =packet_notifier,
1876 };
1877
1878 #ifdef CONFIG_PROC_FS
1879 static inline struct sock *packet_seq_idx(loff_t off)
1880 {
1881 struct sock *s;
1882 struct hlist_node *node;
1883
1884 sk_for_each(s, node, &packet_sklist) {
1885 if (!off--)
1886 return s;
1887 }
1888 return NULL;
1889 }
1890
1891 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
1892 {
1893 read_lock(&packet_sklist_lock);
1894 return *pos ? packet_seq_idx(*pos - 1) : SEQ_START_TOKEN;
1895 }
1896
1897 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1898 {
1899 ++*pos;
1900 return (v == SEQ_START_TOKEN)
1901 ? sk_head(&packet_sklist)
1902 : sk_next((struct sock*)v) ;
1903 }
1904
1905 static void packet_seq_stop(struct seq_file *seq, void *v)
1906 {
1907 read_unlock(&packet_sklist_lock);
1908 }
1909
1910 static int packet_seq_show(struct seq_file *seq, void *v)
1911 {
1912 if (v == SEQ_START_TOKEN)
1913 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
1914 else {
1915 struct sock *s = v;
1916 const struct packet_sock *po = pkt_sk(s);
1917
1918 seq_printf(seq,
1919 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
1920 s,
1921 atomic_read(&s->sk_refcnt),
1922 s->sk_type,
1923 ntohs(po->num),
1924 po->ifindex,
1925 po->running,
1926 atomic_read(&s->sk_rmem_alloc),
1927 sock_i_uid(s),
1928 sock_i_ino(s) );
1929 }
1930
1931 return 0;
1932 }
1933
1934 static const struct seq_operations packet_seq_ops = {
1935 .start = packet_seq_start,
1936 .next = packet_seq_next,
1937 .stop = packet_seq_stop,
1938 .show = packet_seq_show,
1939 };
1940
1941 static int packet_seq_open(struct inode *inode, struct file *file)
1942 {
1943 return seq_open(file, &packet_seq_ops);
1944 }
1945
1946 static const struct file_operations packet_seq_fops = {
1947 .owner = THIS_MODULE,
1948 .open = packet_seq_open,
1949 .read = seq_read,
1950 .llseek = seq_lseek,
1951 .release = seq_release,
1952 };
1953
1954 #endif
1955
1956 static void __exit packet_exit(void)
1957 {
1958 proc_net_remove(&init_net, "packet");
1959 unregister_netdevice_notifier(&packet_netdev_notifier);
1960 sock_unregister(PF_PACKET);
1961 proto_unregister(&packet_proto);
1962 }
1963
1964 static int __init packet_init(void)
1965 {
1966 int rc = proto_register(&packet_proto, 0);
1967
1968 if (rc != 0)
1969 goto out;
1970
1971 sock_register(&packet_family_ops);
1972 register_netdevice_notifier(&packet_netdev_notifier);
1973 proc_net_fops_create(&init_net, "packet", 0, &packet_seq_fops);
1974 out:
1975 return rc;
1976 }
1977
1978 module_init(packet_init);
1979 module_exit(packet_exit);
1980 MODULE_LICENSE("GPL");
1981 MODULE_ALIAS_NETPROTO(PF_PACKET);
Linux kernel - Deliverables
This page took 0.088739 seconds and 6 git commands to generate.