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[CPUFREQ] Remove unneeded errata workaround from p4-clockmod.
[linux-2.6/zen-sources.git] / net / packet / af_packet.c
blob6dc01bdeb76bad39984322efa4d4467e3d86f6db
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/sched.h>
54 #include <linux/mm.h>
55 #include <linux/capability.h>
56 #include <linux/fcntl.h>
57 #include <linux/socket.h>
58 #include <linux/in.h>
59 #include <linux/inet.h>
60 #include <linux/netdevice.h>
61 #include <linux/if_packet.h>
62 #include <linux/wireless.h>
63 #include <linux/kmod.h>
64 #include <net/ip.h>
65 #include <net/protocol.h>
66 #include <linux/skbuff.h>
67 #include <net/sock.h>
68 #include <linux/errno.h>
69 #include <linux/timer.h>
70 #include <asm/system.h>
71 #include <asm/uaccess.h>
72 #include <asm/ioctls.h>
73 #include <asm/page.h>
74 #include <asm/cacheflush.h>
75 #include <asm/io.h>
76 #include <linux/proc_fs.h>
77 #include <linux/seq_file.h>
78 #include <linux/poll.h>
79 #include <linux/module.h>
80 #include <linux/init.h>
81
82 #ifdef CONFIG_INET
83 #include <net/inet_common.h>
84 #endif
85
86 #define CONFIG_SOCK_PACKET 1
87
88 /*
89 Proposed replacement for SIOC{ADD,DEL}MULTI and
90 IFF_PROMISC, IFF_ALLMULTI flags.
91
92 It is more expensive, but I believe,
93 it is really correct solution: reentereble, safe and fault tolerant.
94
95 IFF_PROMISC/IFF_ALLMULTI/SIOC{ADD/DEL}MULTI are faked by keeping
96 reference count and global flag, so that real status is
97 (gflag|(count != 0)), so that we can use obsolete faulty interface
98 not harming clever users.
99 */
100 #define CONFIG_PACKET_MULTICAST 1
101
102 /*
103 Assumptions:
104 - if device has no dev->hard_header routine, it adds and removes ll header
105 inside itself. In this case ll header is invisible outside of device,
106 but higher levels still should reserve dev->hard_header_len.
107 Some devices are enough clever to reallocate skb, when header
108 will not fit to reserved space (tunnel), another ones are silly
109 (PPP).
110 - packet socket receives packets with pulled ll header,
111 so that SOCK_RAW should push it back.
112
113 On receive:
114 -----------
115
116 Incoming, dev->hard_header!=NULL
117 mac.raw -> ll header
118 data -> data
119
120 Outgoing, dev->hard_header!=NULL
121 mac.raw -> ll header
122 data -> ll header
123
124 Incoming, dev->hard_header==NULL
125 mac.raw -> UNKNOWN position. It is very likely, that it points to ll header.
126 PPP makes it, that is wrong, because introduce assymetry
127 between rx and tx paths.
128 data -> data
129
130 Outgoing, dev->hard_header==NULL
131 mac.raw -> data. ll header is still not built!
132 data -> data
133
134 Resume
135 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
136
137
138 On transmit:
139 ------------
140
141 dev->hard_header != NULL
142 mac.raw -> ll header
143 data -> ll header
144
145 dev->hard_header == NULL (ll header is added by device, we cannot control it)
146 mac.raw -> data
147 data -> data
148
149 We should set nh.raw on output to correct posistion,
150 packet classifier depends on it.
151 */
152
153 /* List of all packet sockets. */
154 static HLIST_HEAD(packet_sklist);
155 static DEFINE_RWLOCK(packet_sklist_lock);
156
157 static atomic_t packet_socks_nr;
158
159
160 /* Private packet socket structures. */
161
162 #ifdef CONFIG_PACKET_MULTICAST
163 struct packet_mclist
164 {
165 struct packet_mclist *next;
166 int ifindex;
167 int count;
168 unsigned short type;
169 unsigned short alen;
170 unsigned char addr[MAX_ADDR_LEN];
171 };
172 /* identical to struct packet_mreq except it has
173 * a longer address field.
174 */
175 struct packet_mreq_max
176 {
177 int mr_ifindex;
178 unsigned short mr_type;
179 unsigned short mr_alen;
180 unsigned char mr_address[MAX_ADDR_LEN];
181 };
182 #endif
183 #ifdef CONFIG_PACKET_MMAP
184 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
185 #endif
186
187 static void packet_flush_mclist(struct sock *sk);
188
189 struct packet_sock {
190 /* struct sock has to be the first member of packet_sock */
191 struct sock sk;
192 struct tpacket_stats stats;
193 #ifdef CONFIG_PACKET_MMAP
194 char * *pg_vec;
195 unsigned int head;
196 unsigned int frames_per_block;
197 unsigned int frame_size;
198 unsigned int frame_max;
199 int copy_thresh;
200 #endif
201 struct packet_type prot_hook;
202 spinlock_t bind_lock;
203 char running; /* prot_hook is attached*/
204 int ifindex; /* bound device */
205 __be16 num;
206 #ifdef CONFIG_PACKET_MULTICAST
207 struct packet_mclist *mclist;
208 #endif
209 #ifdef CONFIG_PACKET_MMAP
210 atomic_t mapped;
211 unsigned int pg_vec_order;
212 unsigned int pg_vec_pages;
213 unsigned int pg_vec_len;
214 #endif
215 };
216
217 #ifdef CONFIG_PACKET_MMAP
218
219 static inline char *packet_lookup_frame(struct packet_sock *po, unsigned int position)
220 {
221 unsigned int pg_vec_pos, frame_offset;
222 char *frame;
223
224 pg_vec_pos = position / po->frames_per_block;
225 frame_offset = position % po->frames_per_block;
226
227 frame = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
228
229 return frame;
230 }
231 #endif
232
233 static inline struct packet_sock *pkt_sk(struct sock *sk)
234 {
235 return (struct packet_sock *)sk;
236 }
237
238 static void packet_sock_destruct(struct sock *sk)
239 {
240 BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
241 BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
242
243 if (!sock_flag(sk, SOCK_DEAD)) {
244 printk("Attempt to release alive packet socket: %p\n", sk);
245 return;
246 }
247
248 atomic_dec(&packet_socks_nr);
249 #ifdef PACKET_REFCNT_DEBUG
250 printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
251 #endif
252 }
253
254
255 static const struct proto_ops packet_ops;
256
257 #ifdef CONFIG_SOCK_PACKET
258 static const struct proto_ops packet_ops_spkt;
259
260 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
261 {
262 struct sock *sk;
263 struct sockaddr_pkt *spkt;
264
265 /*
266 * When we registered the protocol we saved the socket in the data
267 * field for just this event.
268 */
269
270 sk = pt->af_packet_priv;
271
272 /*
273 * Yank back the headers [hope the device set this
274 * right or kerboom...]
275 *
276 * Incoming packets have ll header pulled,
277 * push it back.
278 *
279 * For outgoing ones skb->data == skb->mac.raw
280 * so that this procedure is noop.
281 */
282
283 if (skb->pkt_type == PACKET_LOOPBACK)
284 goto out;
285
286 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
287 goto oom;
288
289 /* drop any routing info */
290 dst_release(skb->dst);
291 skb->dst = NULL;
292
293 /* drop conntrack reference */
294 nf_reset(skb);
295
296 spkt = (struct sockaddr_pkt*)skb->cb;
297
298 skb_push(skb, skb->data-skb->mac.raw);
299
300 /*
301 * The SOCK_PACKET socket receives _all_ frames.
302 */
303
304 spkt->spkt_family = dev->type;
305 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
306 spkt->spkt_protocol = skb->protocol;
307
308 /*
309 * Charge the memory to the socket. This is done specifically
310 * to prevent sockets using all the memory up.
311 */
312
313 if (sock_queue_rcv_skb(sk,skb) == 0)
314 return 0;
315
316 out:
317 kfree_skb(skb);
318 oom:
319 return 0;
320 }
321
322
323 /*
324 * Output a raw packet to a device layer. This bypasses all the other
325 * protocol layers and you must therefore supply it with a complete frame
326 */
327
328 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
329 struct msghdr *msg, size_t len)
330 {
331 struct sock *sk = sock->sk;
332 struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
333 struct sk_buff *skb;
334 struct net_device *dev;
335 __be16 proto=0;
336 int err;
337
338 /*
339 * Get and verify the address.
340 */
341
342 if (saddr)
343 {
344 if (msg->msg_namelen < sizeof(struct sockaddr))
345 return(-EINVAL);
346 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
347 proto=saddr->spkt_protocol;
348 }
349 else
350 return(-ENOTCONN); /* SOCK_PACKET must be sent giving an address */
351
352 /*
353 * Find the device first to size check it
354 */
355
356 saddr->spkt_device[13] = 0;
357 dev = dev_get_by_name(saddr->spkt_device);
358 err = -ENODEV;
359 if (dev == NULL)
360 goto out_unlock;
361
362 err = -ENETDOWN;
363 if (!(dev->flags & IFF_UP))
364 goto out_unlock;
365
366 /*
367 * You may not queue a frame bigger than the mtu. This is the lowest level
368 * raw protocol and you must do your own fragmentation at this level.
369 */
370
371 err = -EMSGSIZE;
372 if (len > dev->mtu + dev->hard_header_len)
373 goto out_unlock;
374
375 err = -ENOBUFS;
376 skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
377
378 /*
379 * If the write buffer is full, then tough. At this level the user gets to
380 * deal with the problem - do your own algorithmic backoffs. That's far
381 * more flexible.
382 */
383
384 if (skb == NULL)
385 goto out_unlock;
386
387 /*
388 * Fill it in
389 */
390
391 /* FIXME: Save some space for broken drivers that write a
392 * hard header at transmission time by themselves. PPP is the
393 * notable one here. This should really be fixed at the driver level.
394 */
395 skb_reserve(skb, LL_RESERVED_SPACE(dev));
396 skb->nh.raw = skb->data;
397
398 /* Try to align data part correctly */
399 if (dev->hard_header) {
400 skb->data -= dev->hard_header_len;
401 skb->tail -= dev->hard_header_len;
402 if (len < dev->hard_header_len)
403 skb->nh.raw = skb->data;
404 }
405
406 /* Returns -EFAULT on error */
407 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
408 skb->protocol = proto;
409 skb->dev = dev;
410 skb->priority = sk->sk_priority;
411 if (err)
412 goto out_free;
413
414 /*
415 * Now send it
416 */
417
418 dev_queue_xmit(skb);
419 dev_put(dev);
420 return(len);
421
422 out_free:
423 kfree_skb(skb);
424 out_unlock:
425 if (dev)
426 dev_put(dev);
427 return err;
428 }
429 #endif
430
431 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
432 unsigned int res)
433 {
434 struct sk_filter *filter;
435
436 rcu_read_lock_bh();
437 filter = rcu_dereference(sk->sk_filter);
438 if (filter != NULL)
439 res = sk_run_filter(skb, filter->insns, filter->len);
440 rcu_read_unlock_bh();
441
442 return res;
443 }
444
445 /*
446 This function makes lazy skb cloning in hope that most of packets
447 are discarded by BPF.
448
449 Note tricky part: we DO mangle shared skb! skb->data, skb->len
450 and skb->cb are mangled. It works because (and until) packets
451 falling here are owned by current CPU. Output packets are cloned
452 by dev_queue_xmit_nit(), input packets are processed by net_bh
453 sequencially, so that if we return skb to original state on exit,
454 we will not harm anyone.
455 */
456
457 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
458 {
459 struct sock *sk;
460 struct sockaddr_ll *sll;
461 struct packet_sock *po;
462 u8 * skb_head = skb->data;
463 int skb_len = skb->len;
464 unsigned int snaplen, res;
465
466 if (skb->pkt_type == PACKET_LOOPBACK)
467 goto drop;
468
469 sk = pt->af_packet_priv;
470 po = pkt_sk(sk);
471
472 skb->dev = dev;
473
474 if (dev->hard_header) {
475 /* The device has an explicit notion of ll header,
476 exported to higher levels.
477
478 Otherwise, the device hides datails of it frame
479 structure, so that corresponding packet head
480 never delivered to user.
481 */
482 if (sk->sk_type != SOCK_DGRAM)
483 skb_push(skb, skb->data - skb->mac.raw);
484 else if (skb->pkt_type == PACKET_OUTGOING) {
485 /* Special case: outgoing packets have ll header at head */
486 skb_pull(skb, skb->nh.raw - skb->data);
487 }
488 }
489
490 snaplen = skb->len;
491
492 res = run_filter(skb, sk, snaplen);
493 if (!res)
494 goto drop_n_restore;
495 if (snaplen > res)
496 snaplen = res;
497
498 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
499 (unsigned)sk->sk_rcvbuf)
500 goto drop_n_acct;
501
502 if (skb_shared(skb)) {
503 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
504 if (nskb == NULL)
505 goto drop_n_acct;
506
507 if (skb_head != skb->data) {
508 skb->data = skb_head;
509 skb->len = skb_len;
510 }
511 kfree_skb(skb);
512 skb = nskb;
513 }
514
515 sll = (struct sockaddr_ll*)skb->cb;
516 sll->sll_family = AF_PACKET;
517 sll->sll_hatype = dev->type;
518 sll->sll_protocol = skb->protocol;
519 sll->sll_pkttype = skb->pkt_type;
520 sll->sll_ifindex = dev->ifindex;
521 sll->sll_halen = 0;
522
523 if (dev->hard_header_parse)
524 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
525
526 if (pskb_trim(skb, snaplen))
527 goto drop_n_acct;
528
529 skb_set_owner_r(skb, sk);
530 skb->dev = NULL;
531 dst_release(skb->dst);
532 skb->dst = NULL;
533
534 /* drop conntrack reference */
535 nf_reset(skb);
536
537 spin_lock(&sk->sk_receive_queue.lock);
538 po->stats.tp_packets++;
539 __skb_queue_tail(&sk->sk_receive_queue, skb);
540 spin_unlock(&sk->sk_receive_queue.lock);
541 sk->sk_data_ready(sk, skb->len);
542 return 0;
543
544 drop_n_acct:
545 spin_lock(&sk->sk_receive_queue.lock);
546 po->stats.tp_drops++;
547 spin_unlock(&sk->sk_receive_queue.lock);
548
549 drop_n_restore:
550 if (skb_head != skb->data && skb_shared(skb)) {
551 skb->data = skb_head;
552 skb->len = skb_len;
553 }
554 drop:
555 kfree_skb(skb);
556 return 0;
557 }
558
559 #ifdef CONFIG_PACKET_MMAP
560 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
561 {
562 struct sock *sk;
563 struct packet_sock *po;
564 struct sockaddr_ll *sll;
565 struct tpacket_hdr *h;
566 u8 * skb_head = skb->data;
567 int skb_len = skb->len;
568 unsigned int snaplen, res;
569 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
570 unsigned short macoff, netoff;
571 struct sk_buff *copy_skb = NULL;
572
573 if (skb->pkt_type == PACKET_LOOPBACK)
574 goto drop;
575
576 sk = pt->af_packet_priv;
577 po = pkt_sk(sk);
578
579 if (dev->hard_header) {
580 if (sk->sk_type != SOCK_DGRAM)
581 skb_push(skb, skb->data - skb->mac.raw);
582 else if (skb->pkt_type == PACKET_OUTGOING) {
583 /* Special case: outgoing packets have ll header at head */
584 skb_pull(skb, skb->nh.raw - skb->data);
585 if (skb->ip_summed == CHECKSUM_PARTIAL)
586 status |= TP_STATUS_CSUMNOTREADY;
587 }
588 }
589
590 snaplen = skb->len;
591
592 res = run_filter(skb, sk, snaplen);
593 if (!res)
594 goto drop_n_restore;
595 if (snaplen > res)
596 snaplen = res;
597
598 if (sk->sk_type == SOCK_DGRAM) {
599 macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
600 } else {
601 unsigned maclen = skb->nh.raw - skb->data;
602 netoff = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
603 macoff = netoff - maclen;
604 }
605
606 if (macoff + snaplen > po->frame_size) {
607 if (po->copy_thresh &&
608 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
609 (unsigned)sk->sk_rcvbuf) {
610 if (skb_shared(skb)) {
611 copy_skb = skb_clone(skb, GFP_ATOMIC);
612 } else {
613 copy_skb = skb_get(skb);
614 skb_head = skb->data;
615 }
616 if (copy_skb)
617 skb_set_owner_r(copy_skb, sk);
618 }
619 snaplen = po->frame_size - macoff;
620 if ((int)snaplen < 0)
621 snaplen = 0;
622 }
623
624 spin_lock(&sk->sk_receive_queue.lock);
625 h = (struct tpacket_hdr *)packet_lookup_frame(po, po->head);
626
627 if (h->tp_status)
628 goto ring_is_full;
629 po->head = po->head != po->frame_max ? po->head+1 : 0;
630 po->stats.tp_packets++;
631 if (copy_skb) {
632 status |= TP_STATUS_COPY;
633 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
634 }
635 if (!po->stats.tp_drops)
636 status &= ~TP_STATUS_LOSING;
637 spin_unlock(&sk->sk_receive_queue.lock);
638
639 skb_copy_bits(skb, 0, (u8*)h + macoff, snaplen);
640
641 h->tp_len = skb->len;
642 h->tp_snaplen = snaplen;
643 h->tp_mac = macoff;
644 h->tp_net = netoff;
645 if (skb->tstamp.off_sec == 0) {
646 __net_timestamp(skb);
647 sock_enable_timestamp(sk);
648 }
649 h->tp_sec = skb->tstamp.off_sec;
650 h->tp_usec = skb->tstamp.off_usec;
651
652 sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
653 sll->sll_halen = 0;
654 if (dev->hard_header_parse)
655 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
656 sll->sll_family = AF_PACKET;
657 sll->sll_hatype = dev->type;
658 sll->sll_protocol = skb->protocol;
659 sll->sll_pkttype = skb->pkt_type;
660 sll->sll_ifindex = dev->ifindex;
661
662 h->tp_status = status;
663 smp_mb();
664
665 {
666 struct page *p_start, *p_end;
667 u8 *h_end = (u8 *)h + macoff + snaplen - 1;
668
669 p_start = virt_to_page(h);
670 p_end = virt_to_page(h_end);
671 while (p_start <= p_end) {
672 flush_dcache_page(p_start);
673 p_start++;
674 }
675 }
676
677 sk->sk_data_ready(sk, 0);
678
679 drop_n_restore:
680 if (skb_head != skb->data && skb_shared(skb)) {
681 skb->data = skb_head;
682 skb->len = skb_len;
683 }
684 drop:
685 kfree_skb(skb);
686 return 0;
687
688 ring_is_full:
689 po->stats.tp_drops++;
690 spin_unlock(&sk->sk_receive_queue.lock);
691
692 sk->sk_data_ready(sk, 0);
693 if (copy_skb)
694 kfree_skb(copy_skb);
695 goto drop_n_restore;
696 }
697
698 #endif
699
700
701 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
702 struct msghdr *msg, size_t len)
703 {
704 struct sock *sk = sock->sk;
705 struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
706 struct sk_buff *skb;
707 struct net_device *dev;
708 __be16 proto;
709 unsigned char *addr;
710 int ifindex, err, reserve = 0;
711
712 /*
713 * Get and verify the address.
714 */
715
716 if (saddr == NULL) {
717 struct packet_sock *po = pkt_sk(sk);
718
719 ifindex = po->ifindex;
720 proto = po->num;
721 addr = NULL;
722 } else {
723 err = -EINVAL;
724 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
725 goto out;
726 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
727 goto out;
728 ifindex = saddr->sll_ifindex;
729 proto = saddr->sll_protocol;
730 addr = saddr->sll_addr;
731 }
732
733
734 dev = dev_get_by_index(ifindex);
735 err = -ENXIO;
736 if (dev == NULL)
737 goto out_unlock;
738 if (sock->type == SOCK_RAW)
739 reserve = dev->hard_header_len;
740
741 err = -ENETDOWN;
742 if (!(dev->flags & IFF_UP))
743 goto out_unlock;
744
745 err = -EMSGSIZE;
746 if (len > dev->mtu+reserve)
747 goto out_unlock;
748
749 skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
750 msg->msg_flags & MSG_DONTWAIT, &err);
751 if (skb==NULL)
752 goto out_unlock;
753
754 skb_reserve(skb, LL_RESERVED_SPACE(dev));
755 skb->nh.raw = skb->data;
756
757 if (dev->hard_header) {
758 int res;
759 err = -EINVAL;
760 res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
761 if (sock->type != SOCK_DGRAM) {
762 skb->tail = skb->data;
763 skb->len = 0;
764 } else if (res < 0)
765 goto out_free;
766 }
767
768 /* Returns -EFAULT on error */
769 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
770 if (err)
771 goto out_free;
772
773 skb->protocol = proto;
774 skb->dev = dev;
775 skb->priority = sk->sk_priority;
776
777 /*
778 * Now send it
779 */
780
781 err = dev_queue_xmit(skb);
782 if (err > 0 && (err = net_xmit_errno(err)) != 0)
783 goto out_unlock;
784
785 dev_put(dev);
786
787 return(len);
788
789 out_free:
790 kfree_skb(skb);
791 out_unlock:
792 if (dev)
793 dev_put(dev);
794 out:
795 return err;
796 }
797
798 /*
799 * Close a PACKET socket. This is fairly simple. We immediately go
800 * to 'closed' state and remove our protocol entry in the device list.
801 */
802
803 static int packet_release(struct socket *sock)
804 {
805 struct sock *sk = sock->sk;
806 struct packet_sock *po;
807
808 if (!sk)
809 return 0;
810
811 po = pkt_sk(sk);
812
813 write_lock_bh(&packet_sklist_lock);
814 sk_del_node_init(sk);
815 write_unlock_bh(&packet_sklist_lock);
816
817 /*
818 * Unhook packet receive handler.
819 */
820
821 if (po->running) {
822 /*
823 * Remove the protocol hook
824 */
825 dev_remove_pack(&po->prot_hook);
826 po->running = 0;
827 po->num = 0;
828 __sock_put(sk);
829 }
830
831 #ifdef CONFIG_PACKET_MULTICAST
832 packet_flush_mclist(sk);
833 #endif
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 #ifdef CONFIG_SOCK_PACKET
917
918 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
919 {
920 struct sock *sk=sock->sk;
921 char name[15];
922 struct net_device *dev;
923 int err = -ENODEV;
924
925 /*
926 * Check legality
927 */
928
929 if (addr_len != sizeof(struct sockaddr))
930 return -EINVAL;
931 strlcpy(name,uaddr->sa_data,sizeof(name));
932
933 dev = dev_get_by_name(name);
934 if (dev) {
935 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
936 dev_put(dev);
937 }
938 return err;
939 }
940 #endif
941
942 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
943 {
944 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
945 struct sock *sk=sock->sk;
946 struct net_device *dev = NULL;
947 int err;
948
949
950 /*
951 * Check legality
952 */
953
954 if (addr_len < sizeof(struct sockaddr_ll))
955 return -EINVAL;
956 if (sll->sll_family != AF_PACKET)
957 return -EINVAL;
958
959 if (sll->sll_ifindex) {
960 err = -ENODEV;
961 dev = dev_get_by_index(sll->sll_ifindex);
962 if (dev == NULL)
963 goto out;
964 }
965 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
966 if (dev)
967 dev_put(dev);
968
969 out:
970 return err;
971 }
972
973 static struct proto packet_proto = {
974 .name = "PACKET",
975 .owner = THIS_MODULE,
976 .obj_size = sizeof(struct packet_sock),
977 };
978
979 /*
980 * Create a packet of type SOCK_PACKET.
981 */
982
983 static int packet_create(struct socket *sock, int protocol)
984 {
985 struct sock *sk;
986 struct packet_sock *po;
987 __be16 proto = (__force __be16)protocol; /* weird, but documented */
988 int err;
989
990 if (!capable(CAP_NET_RAW))
991 return -EPERM;
992 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW
993 #ifdef CONFIG_SOCK_PACKET
994 && sock->type != SOCK_PACKET
995 #endif
996 )
997 return -ESOCKTNOSUPPORT;
998
999 sock->state = SS_UNCONNECTED;
1000
1001 err = -ENOBUFS;
1002 sk = sk_alloc(PF_PACKET, GFP_KERNEL, &packet_proto, 1);
1003 if (sk == NULL)
1004 goto out;
1005
1006 sock->ops = &packet_ops;
1007 #ifdef CONFIG_SOCK_PACKET
1008 if (sock->type == SOCK_PACKET)
1009 sock->ops = &packet_ops_spkt;
1010 #endif
1011 sock_init_data(sock, sk);
1012
1013 po = pkt_sk(sk);
1014 sk->sk_family = PF_PACKET;
1015 po->num = proto;
1016
1017 sk->sk_destruct = packet_sock_destruct;
1018 atomic_inc(&packet_socks_nr);
1019
1020 /*
1021 * Attach a protocol block
1022 */
1023
1024 spin_lock_init(&po->bind_lock);
1025 po->prot_hook.func = packet_rcv;
1026 #ifdef CONFIG_SOCK_PACKET
1027 if (sock->type == SOCK_PACKET)
1028 po->prot_hook.func = packet_rcv_spkt;
1029 #endif
1030 po->prot_hook.af_packet_priv = sk;
1031
1032 if (proto) {
1033 po->prot_hook.type = proto;
1034 dev_add_pack(&po->prot_hook);
1035 sock_hold(sk);
1036 po->running = 1;
1037 }
1038
1039 write_lock_bh(&packet_sklist_lock);
1040 sk_add_node(sk, &packet_sklist);
1041 write_unlock_bh(&packet_sklist_lock);
1042 return(0);
1043 out:
1044 return err;
1045 }
1046
1047 /*
1048 * Pull a packet from our receive queue and hand it to the user.
1049 * If necessary we block.
1050 */
1051
1052 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1053 struct msghdr *msg, size_t len, int flags)
1054 {
1055 struct sock *sk = sock->sk;
1056 struct sk_buff *skb;
1057 int copied, err;
1058 struct sockaddr_ll *sll;
1059
1060 err = -EINVAL;
1061 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1062 goto out;
1063
1064 #if 0
1065 /* What error should we return now? EUNATTACH? */
1066 if (pkt_sk(sk)->ifindex < 0)
1067 return -ENODEV;
1068 #endif
1069
1070 /*
1071 * Call the generic datagram receiver. This handles all sorts
1072 * of horrible races and re-entrancy so we can forget about it
1073 * in the protocol layers.
1074 *
1075 * Now it will return ENETDOWN, if device have just gone down,
1076 * but then it will block.
1077 */
1078
1079 skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1080
1081 /*
1082 * An error occurred so return it. Because skb_recv_datagram()
1083 * handles the blocking we don't see and worry about blocking
1084 * retries.
1085 */
1086
1087 if (skb == NULL)
1088 goto out;
1089
1090 /*
1091 * If the address length field is there to be filled in, we fill
1092 * it in now.
1093 */
1094
1095 sll = (struct sockaddr_ll*)skb->cb;
1096 if (sock->type == SOCK_PACKET)
1097 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1098 else
1099 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1100
1101 /*
1102 * You lose any data beyond the buffer you gave. If it worries a
1103 * user program they can ask the device for its MTU anyway.
1104 */
1105
1106 copied = skb->len;
1107 if (copied > len)
1108 {
1109 copied=len;
1110 msg->msg_flags|=MSG_TRUNC;
1111 }
1112
1113 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1114 if (err)
1115 goto out_free;
1116
1117 sock_recv_timestamp(msg, sk, skb);
1118
1119 if (msg->msg_name)
1120 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1121
1122 /*
1123 * Free or return the buffer as appropriate. Again this
1124 * hides all the races and re-entrancy issues from us.
1125 */
1126 err = (flags&MSG_TRUNC) ? skb->len : copied;
1127
1128 out_free:
1129 skb_free_datagram(sk, skb);
1130 out:
1131 return err;
1132 }
1133
1134 #ifdef CONFIG_SOCK_PACKET
1135 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1136 int *uaddr_len, int peer)
1137 {
1138 struct net_device *dev;
1139 struct sock *sk = sock->sk;
1140
1141 if (peer)
1142 return -EOPNOTSUPP;
1143
1144 uaddr->sa_family = AF_PACKET;
1145 dev = dev_get_by_index(pkt_sk(sk)->ifindex);
1146 if (dev) {
1147 strlcpy(uaddr->sa_data, dev->name, 15);
1148 dev_put(dev);
1149 } else
1150 memset(uaddr->sa_data, 0, 14);
1151 *uaddr_len = sizeof(*uaddr);
1152
1153 return 0;
1154 }
1155 #endif
1156
1157 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1158 int *uaddr_len, int peer)
1159 {
1160 struct net_device *dev;
1161 struct sock *sk = sock->sk;
1162 struct packet_sock *po = pkt_sk(sk);
1163 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1164
1165 if (peer)
1166 return -EOPNOTSUPP;
1167
1168 sll->sll_family = AF_PACKET;
1169 sll->sll_ifindex = po->ifindex;
1170 sll->sll_protocol = po->num;
1171 dev = dev_get_by_index(po->ifindex);
1172 if (dev) {
1173 sll->sll_hatype = dev->type;
1174 sll->sll_halen = dev->addr_len;
1175 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1176 dev_put(dev);
1177 } else {
1178 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
1179 sll->sll_halen = 0;
1180 }
1181 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1182
1183 return 0;
1184 }
1185
1186 #ifdef CONFIG_PACKET_MULTICAST
1187 static void packet_dev_mc(struct net_device *dev, struct packet_mclist *i, int what)
1188 {
1189 switch (i->type) {
1190 case PACKET_MR_MULTICAST:
1191 if (what > 0)
1192 dev_mc_add(dev, i->addr, i->alen, 0);
1193 else
1194 dev_mc_delete(dev, i->addr, i->alen, 0);
1195 break;
1196 case PACKET_MR_PROMISC:
1197 dev_set_promiscuity(dev, what);
1198 break;
1199 case PACKET_MR_ALLMULTI:
1200 dev_set_allmulti(dev, what);
1201 break;
1202 default:;
1203 }
1204 }
1205
1206 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1207 {
1208 for ( ; i; i=i->next) {
1209 if (i->ifindex == dev->ifindex)
1210 packet_dev_mc(dev, i, what);
1211 }
1212 }
1213
1214 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1215 {
1216 struct packet_sock *po = pkt_sk(sk);
1217 struct packet_mclist *ml, *i;
1218 struct net_device *dev;
1219 int err;
1220
1221 rtnl_lock();
1222
1223 err = -ENODEV;
1224 dev = __dev_get_by_index(mreq->mr_ifindex);
1225 if (!dev)
1226 goto done;
1227
1228 err = -EINVAL;
1229 if (mreq->mr_alen > dev->addr_len)
1230 goto done;
1231
1232 err = -ENOBUFS;
1233 i = kmalloc(sizeof(*i), GFP_KERNEL);
1234 if (i == NULL)
1235 goto done;
1236
1237 err = 0;
1238 for (ml = po->mclist; ml; ml = ml->next) {
1239 if (ml->ifindex == mreq->mr_ifindex &&
1240 ml->type == mreq->mr_type &&
1241 ml->alen == mreq->mr_alen &&
1242 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1243 ml->count++;
1244 /* Free the new element ... */
1245 kfree(i);
1246 goto done;
1247 }
1248 }
1249
1250 i->type = mreq->mr_type;
1251 i->ifindex = mreq->mr_ifindex;
1252 i->alen = mreq->mr_alen;
1253 memcpy(i->addr, mreq->mr_address, i->alen);
1254 i->count = 1;
1255 i->next = po->mclist;
1256 po->mclist = i;
1257 packet_dev_mc(dev, i, +1);
1258
1259 done:
1260 rtnl_unlock();
1261 return err;
1262 }
1263
1264 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1265 {
1266 struct packet_mclist *ml, **mlp;
1267
1268 rtnl_lock();
1269
1270 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1271 if (ml->ifindex == mreq->mr_ifindex &&
1272 ml->type == mreq->mr_type &&
1273 ml->alen == mreq->mr_alen &&
1274 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1275 if (--ml->count == 0) {
1276 struct net_device *dev;
1277 *mlp = ml->next;
1278 dev = dev_get_by_index(ml->ifindex);
1279 if (dev) {
1280 packet_dev_mc(dev, ml, -1);
1281 dev_put(dev);
1282 }
1283 kfree(ml);
1284 }
1285 rtnl_unlock();
1286 return 0;
1287 }
1288 }
1289 rtnl_unlock();
1290 return -EADDRNOTAVAIL;
1291 }
1292
1293 static void packet_flush_mclist(struct sock *sk)
1294 {
1295 struct packet_sock *po = pkt_sk(sk);
1296 struct packet_mclist *ml;
1297
1298 if (!po->mclist)
1299 return;
1300
1301 rtnl_lock();
1302 while ((ml = po->mclist) != NULL) {
1303 struct net_device *dev;
1304
1305 po->mclist = ml->next;
1306 if ((dev = dev_get_by_index(ml->ifindex)) != NULL) {
1307 packet_dev_mc(dev, ml, -1);
1308 dev_put(dev);
1309 }
1310 kfree(ml);
1311 }
1312 rtnl_unlock();
1313 }
1314 #endif
1315
1316 static int
1317 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1318 {
1319 struct sock *sk = sock->sk;
1320 int ret;
1321
1322 if (level != SOL_PACKET)
1323 return -ENOPROTOOPT;
1324
1325 switch(optname) {
1326 #ifdef CONFIG_PACKET_MULTICAST
1327 case PACKET_ADD_MEMBERSHIP:
1328 case PACKET_DROP_MEMBERSHIP:
1329 {
1330 struct packet_mreq_max mreq;
1331 int len = optlen;
1332 memset(&mreq, 0, sizeof(mreq));
1333 if (len < sizeof(struct packet_mreq))
1334 return -EINVAL;
1335 if (len > sizeof(mreq))
1336 len = sizeof(mreq);
1337 if (copy_from_user(&mreq,optval,len))
1338 return -EFAULT;
1339 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1340 return -EINVAL;
1341 if (optname == PACKET_ADD_MEMBERSHIP)
1342 ret = packet_mc_add(sk, &mreq);
1343 else
1344 ret = packet_mc_drop(sk, &mreq);
1345 return ret;
1346 }
1347 #endif
1348 #ifdef CONFIG_PACKET_MMAP
1349 case PACKET_RX_RING:
1350 {
1351 struct tpacket_req req;
1352
1353 if (optlen<sizeof(req))
1354 return -EINVAL;
1355 if (copy_from_user(&req,optval,sizeof(req)))
1356 return -EFAULT;
1357 return packet_set_ring(sk, &req, 0);
1358 }
1359 case PACKET_COPY_THRESH:
1360 {
1361 int val;
1362
1363 if (optlen!=sizeof(val))
1364 return -EINVAL;
1365 if (copy_from_user(&val,optval,sizeof(val)))
1366 return -EFAULT;
1367
1368 pkt_sk(sk)->copy_thresh = val;
1369 return 0;
1370 }
1371 #endif
1372 default:
1373 return -ENOPROTOOPT;
1374 }
1375 }
1376
1377 static int packet_getsockopt(struct socket *sock, int level, int optname,
1378 char __user *optval, int __user *optlen)
1379 {
1380 int len;
1381 struct sock *sk = sock->sk;
1382 struct packet_sock *po = pkt_sk(sk);
1383
1384 if (level != SOL_PACKET)
1385 return -ENOPROTOOPT;
1386
1387 if (get_user(len, optlen))
1388 return -EFAULT;
1389
1390 if (len < 0)
1391 return -EINVAL;
1392
1393 switch(optname) {
1394 case PACKET_STATISTICS:
1395 {
1396 struct tpacket_stats st;
1397
1398 if (len > sizeof(struct tpacket_stats))
1399 len = sizeof(struct tpacket_stats);
1400 spin_lock_bh(&sk->sk_receive_queue.lock);
1401 st = po->stats;
1402 memset(&po->stats, 0, sizeof(st));
1403 spin_unlock_bh(&sk->sk_receive_queue.lock);
1404 st.tp_packets += st.tp_drops;
1405
1406 if (copy_to_user(optval, &st, len))
1407 return -EFAULT;
1408 break;
1409 }
1410 default:
1411 return -ENOPROTOOPT;
1412 }
1413
1414 if (put_user(len, optlen))
1415 return -EFAULT;
1416 return 0;
1417 }
1418
1419
1420 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1421 {
1422 struct sock *sk;
1423 struct hlist_node *node;
1424 struct net_device *dev = (struct net_device*)data;
1425
1426 read_lock(&packet_sklist_lock);
1427 sk_for_each(sk, node, &packet_sklist) {
1428 struct packet_sock *po = pkt_sk(sk);
1429
1430 switch (msg) {
1431 case NETDEV_UNREGISTER:
1432 #ifdef CONFIG_PACKET_MULTICAST
1433 if (po->mclist)
1434 packet_dev_mclist(dev, po->mclist, -1);
1435 // fallthrough
1436 #endif
1437 case NETDEV_DOWN:
1438 if (dev->ifindex == po->ifindex) {
1439 spin_lock(&po->bind_lock);
1440 if (po->running) {
1441 __dev_remove_pack(&po->prot_hook);
1442 __sock_put(sk);
1443 po->running = 0;
1444 sk->sk_err = ENETDOWN;
1445 if (!sock_flag(sk, SOCK_DEAD))
1446 sk->sk_error_report(sk);
1447 }
1448 if (msg == NETDEV_UNREGISTER) {
1449 po->ifindex = -1;
1450 po->prot_hook.dev = NULL;
1451 }
1452 spin_unlock(&po->bind_lock);
1453 }
1454 break;
1455 case NETDEV_UP:
1456 spin_lock(&po->bind_lock);
1457 if (dev->ifindex == po->ifindex && po->num &&
1458 !po->running) {
1459 dev_add_pack(&po->prot_hook);
1460 sock_hold(sk);
1461 po->running = 1;
1462 }
1463 spin_unlock(&po->bind_lock);
1464 break;
1465 }
1466 }
1467 read_unlock(&packet_sklist_lock);
1468 return NOTIFY_DONE;
1469 }
1470
1471
1472 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1473 unsigned long arg)
1474 {
1475 struct sock *sk = sock->sk;
1476
1477 switch(cmd) {
1478 case SIOCOUTQ:
1479 {
1480 int amount = atomic_read(&sk->sk_wmem_alloc);
1481 return put_user(amount, (int __user *)arg);
1482 }
1483 case SIOCINQ:
1484 {
1485 struct sk_buff *skb;
1486 int amount = 0;
1487
1488 spin_lock_bh(&sk->sk_receive_queue.lock);
1489 skb = skb_peek(&sk->sk_receive_queue);
1490 if (skb)
1491 amount = skb->len;
1492 spin_unlock_bh(&sk->sk_receive_queue.lock);
1493 return put_user(amount, (int __user *)arg);
1494 }
1495 case SIOCGSTAMP:
1496 return sock_get_timestamp(sk, (struct timeval __user *)arg);
1497
1498 #ifdef CONFIG_INET
1499 case SIOCADDRT:
1500 case SIOCDELRT:
1501 case SIOCDARP:
1502 case SIOCGARP:
1503 case SIOCSARP:
1504 case SIOCGIFADDR:
1505 case SIOCSIFADDR:
1506 case SIOCGIFBRDADDR:
1507 case SIOCSIFBRDADDR:
1508 case SIOCGIFNETMASK:
1509 case SIOCSIFNETMASK:
1510 case SIOCGIFDSTADDR:
1511 case SIOCSIFDSTADDR:
1512 case SIOCSIFFLAGS:
1513 return inet_dgram_ops.ioctl(sock, cmd, arg);
1514 #endif
1515
1516 default:
1517 return -ENOIOCTLCMD;
1518 }
1519 return 0;
1520 }
1521
1522 #ifndef CONFIG_PACKET_MMAP
1523 #define packet_mmap sock_no_mmap
1524 #define packet_poll datagram_poll
1525 #else
1526
1527 static unsigned int packet_poll(struct file * file, struct socket *sock,
1528 poll_table *wait)
1529 {
1530 struct sock *sk = sock->sk;
1531 struct packet_sock *po = pkt_sk(sk);
1532 unsigned int mask = datagram_poll(file, sock, wait);
1533
1534 spin_lock_bh(&sk->sk_receive_queue.lock);
1535 if (po->pg_vec) {
1536 unsigned last = po->head ? po->head-1 : po->frame_max;
1537 struct tpacket_hdr *h;
1538
1539 h = (struct tpacket_hdr *)packet_lookup_frame(po, last);
1540
1541 if (h->tp_status)
1542 mask |= POLLIN | POLLRDNORM;
1543 }
1544 spin_unlock_bh(&sk->sk_receive_queue.lock);
1545 return mask;
1546 }
1547
1548
1549 /* Dirty? Well, I still did not learn better way to account
1550 * for user mmaps.
1551 */
1552
1553 static void packet_mm_open(struct vm_area_struct *vma)
1554 {
1555 struct file *file = vma->vm_file;
1556 struct socket * sock = file->private_data;
1557 struct sock *sk = sock->sk;
1558
1559 if (sk)
1560 atomic_inc(&pkt_sk(sk)->mapped);
1561 }
1562
1563 static void packet_mm_close(struct vm_area_struct *vma)
1564 {
1565 struct file *file = vma->vm_file;
1566 struct socket * sock = file->private_data;
1567 struct sock *sk = sock->sk;
1568
1569 if (sk)
1570 atomic_dec(&pkt_sk(sk)->mapped);
1571 }
1572
1573 static struct vm_operations_struct packet_mmap_ops = {
1574 .open = packet_mm_open,
1575 .close =packet_mm_close,
1576 };
1577
1578 static inline struct page *pg_vec_endpage(char *one_pg_vec, unsigned int order)
1579 {
1580 return virt_to_page(one_pg_vec + (PAGE_SIZE << order) - 1);
1581 }
1582
1583 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
1584 {
1585 int i;
1586
1587 for (i = 0; i < len; i++) {
1588 if (likely(pg_vec[i]))
1589 free_pages((unsigned long) pg_vec[i], order);
1590 }
1591 kfree(pg_vec);
1592 }
1593
1594 static inline char *alloc_one_pg_vec_page(unsigned long order)
1595 {
1596 return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
1597 order);
1598 }
1599
1600 static char **alloc_pg_vec(struct tpacket_req *req, int order)
1601 {
1602 unsigned int block_nr = req->tp_block_nr;
1603 char **pg_vec;
1604 int i;
1605
1606 pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
1607 if (unlikely(!pg_vec))
1608 goto out;
1609
1610 for (i = 0; i < block_nr; i++) {
1611 pg_vec[i] = alloc_one_pg_vec_page(order);
1612 if (unlikely(!pg_vec[i]))
1613 goto out_free_pgvec;
1614 }
1615
1616 out:
1617 return pg_vec;
1618
1619 out_free_pgvec:
1620 free_pg_vec(pg_vec, order, block_nr);
1621 pg_vec = NULL;
1622 goto out;
1623 }
1624
1625 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1626 {
1627 char **pg_vec = NULL;
1628 struct packet_sock *po = pkt_sk(sk);
1629 int was_running, order = 0;
1630 __be16 num;
1631 int err = 0;
1632
1633 if (req->tp_block_nr) {
1634 int i, l;
1635
1636 /* Sanity tests and some calculations */
1637
1638 if (unlikely(po->pg_vec))
1639 return -EBUSY;
1640
1641 if (unlikely((int)req->tp_block_size <= 0))
1642 return -EINVAL;
1643 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
1644 return -EINVAL;
1645 if (unlikely(req->tp_frame_size < TPACKET_HDRLEN))
1646 return -EINVAL;
1647 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
1648 return -EINVAL;
1649
1650 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1651 if (unlikely(po->frames_per_block <= 0))
1652 return -EINVAL;
1653 if (unlikely((po->frames_per_block * req->tp_block_nr) !=
1654 req->tp_frame_nr))
1655 return -EINVAL;
1656
1657 err = -ENOMEM;
1658 order = get_order(req->tp_block_size);
1659 pg_vec = alloc_pg_vec(req, order);
1660 if (unlikely(!pg_vec))
1661 goto out;
1662
1663 l = 0;
1664 for (i = 0; i < req->tp_block_nr; i++) {
1665 char *ptr = pg_vec[i];
1666 struct tpacket_hdr *header;
1667 int k;
1668
1669 for (k = 0; k < po->frames_per_block; k++) {
1670 header = (struct tpacket_hdr *) ptr;
1671 header->tp_status = TP_STATUS_KERNEL;
1672 ptr += req->tp_frame_size;
1673 }
1674 }
1675 /* Done */
1676 } else {
1677 if (unlikely(req->tp_frame_nr))
1678 return -EINVAL;
1679 }
1680
1681 lock_sock(sk);
1682
1683 /* Detach socket from network */
1684 spin_lock(&po->bind_lock);
1685 was_running = po->running;
1686 num = po->num;
1687 if (was_running) {
1688 __dev_remove_pack(&po->prot_hook);
1689 po->num = 0;
1690 po->running = 0;
1691 __sock_put(sk);
1692 }
1693 spin_unlock(&po->bind_lock);
1694
1695 synchronize_net();
1696
1697 err = -EBUSY;
1698 if (closing || atomic_read(&po->mapped) == 0) {
1699 err = 0;
1700 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1701
1702 spin_lock_bh(&sk->sk_receive_queue.lock);
1703 pg_vec = XC(po->pg_vec, pg_vec);
1704 po->frame_max = (req->tp_frame_nr - 1);
1705 po->head = 0;
1706 po->frame_size = req->tp_frame_size;
1707 spin_unlock_bh(&sk->sk_receive_queue.lock);
1708
1709 order = XC(po->pg_vec_order, order);
1710 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1711
1712 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1713 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1714 skb_queue_purge(&sk->sk_receive_queue);
1715 #undef XC
1716 if (atomic_read(&po->mapped))
1717 printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1718 }
1719
1720 spin_lock(&po->bind_lock);
1721 if (was_running && !po->running) {
1722 sock_hold(sk);
1723 po->running = 1;
1724 po->num = num;
1725 dev_add_pack(&po->prot_hook);
1726 }
1727 spin_unlock(&po->bind_lock);
1728
1729 release_sock(sk);
1730
1731 if (pg_vec)
1732 free_pg_vec(pg_vec, order, req->tp_block_nr);
1733 out:
1734 return err;
1735 }
1736
1737 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1738 {
1739 struct sock *sk = sock->sk;
1740 struct packet_sock *po = pkt_sk(sk);
1741 unsigned long size;
1742 unsigned long start;
1743 int err = -EINVAL;
1744 int i;
1745
1746 if (vma->vm_pgoff)
1747 return -EINVAL;
1748
1749 size = vma->vm_end - vma->vm_start;
1750
1751 lock_sock(sk);
1752 if (po->pg_vec == NULL)
1753 goto out;
1754 if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1755 goto out;
1756
1757 start = vma->vm_start;
1758 for (i = 0; i < po->pg_vec_len; i++) {
1759 struct page *page = virt_to_page(po->pg_vec[i]);
1760 int pg_num;
1761
1762 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
1763 err = vm_insert_page(vma, start, page);
1764 if (unlikely(err))
1765 goto out;
1766 start += PAGE_SIZE;
1767 }
1768 }
1769 atomic_inc(&po->mapped);
1770 vma->vm_ops = &packet_mmap_ops;
1771 err = 0;
1772
1773 out:
1774 release_sock(sk);
1775 return err;
1776 }
1777 #endif
1778
1779
1780 #ifdef CONFIG_SOCK_PACKET
1781 static const struct proto_ops packet_ops_spkt = {
1782 .family = PF_PACKET,
1783 .owner = THIS_MODULE,
1784 .release = packet_release,
1785 .bind = packet_bind_spkt,
1786 .connect = sock_no_connect,
1787 .socketpair = sock_no_socketpair,
1788 .accept = sock_no_accept,
1789 .getname = packet_getname_spkt,
1790 .poll = datagram_poll,
1791 .ioctl = packet_ioctl,
1792 .listen = sock_no_listen,
1793 .shutdown = sock_no_shutdown,
1794 .setsockopt = sock_no_setsockopt,
1795 .getsockopt = sock_no_getsockopt,
1796 .sendmsg = packet_sendmsg_spkt,
1797 .recvmsg = packet_recvmsg,
1798 .mmap = sock_no_mmap,
1799 .sendpage = sock_no_sendpage,
1800 };
1801 #endif
1802
1803 static const struct proto_ops packet_ops = {
1804 .family = PF_PACKET,
1805 .owner = THIS_MODULE,
1806 .release = packet_release,
1807 .bind = packet_bind,
1808 .connect = sock_no_connect,
1809 .socketpair = sock_no_socketpair,
1810 .accept = sock_no_accept,
1811 .getname = packet_getname,
1812 .poll = packet_poll,
1813 .ioctl = packet_ioctl,
1814 .listen = sock_no_listen,
1815 .shutdown = sock_no_shutdown,
1816 .setsockopt = packet_setsockopt,
1817 .getsockopt = packet_getsockopt,
1818 .sendmsg = packet_sendmsg,
1819 .recvmsg = packet_recvmsg,
1820 .mmap = packet_mmap,
1821 .sendpage = sock_no_sendpage,
1822 };
1823
1824 static struct net_proto_family packet_family_ops = {
1825 .family = PF_PACKET,
1826 .create = packet_create,
1827 .owner = THIS_MODULE,
1828 };
1829
1830 static struct notifier_block packet_netdev_notifier = {
1831 .notifier_call =packet_notifier,
1832 };
1833
1834 #ifdef CONFIG_PROC_FS
1835 static inline struct sock *packet_seq_idx(loff_t off)
1836 {
1837 struct sock *s;
1838 struct hlist_node *node;
1839
1840 sk_for_each(s, node, &packet_sklist) {
1841 if (!off--)
1842 return s;
1843 }
1844 return NULL;
1845 }
1846
1847 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
1848 {
1849 read_lock(&packet_sklist_lock);
1850 return *pos ? packet_seq_idx(*pos - 1) : SEQ_START_TOKEN;
1851 }
1852
1853 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1854 {
1855 ++*pos;
1856 return (v == SEQ_START_TOKEN)
1857 ? sk_head(&packet_sklist)
1858 : sk_next((struct sock*)v) ;
1859 }
1860
1861 static void packet_seq_stop(struct seq_file *seq, void *v)
1862 {
1863 read_unlock(&packet_sklist_lock);
1864 }
1865
1866 static int packet_seq_show(struct seq_file *seq, void *v)
1867 {
1868 if (v == SEQ_START_TOKEN)
1869 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
1870 else {
1871 struct sock *s = v;
1872 const struct packet_sock *po = pkt_sk(s);
1873
1874 seq_printf(seq,
1875 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
1876 s,
1877 atomic_read(&s->sk_refcnt),
1878 s->sk_type,
1879 ntohs(po->num),
1880 po->ifindex,
1881 po->running,
1882 atomic_read(&s->sk_rmem_alloc),
1883 sock_i_uid(s),
1884 sock_i_ino(s) );
1885 }
1886
1887 return 0;
1888 }
1889
1890 static struct seq_operations packet_seq_ops = {
1891 .start = packet_seq_start,
1892 .next = packet_seq_next,
1893 .stop = packet_seq_stop,
1894 .show = packet_seq_show,
1895 };
1896
1897 static int packet_seq_open(struct inode *inode, struct file *file)
1898 {
1899 return seq_open(file, &packet_seq_ops);
1900 }
1901
1902 static struct file_operations packet_seq_fops = {
1903 .owner = THIS_MODULE,
1904 .open = packet_seq_open,
1905 .read = seq_read,
1906 .llseek = seq_lseek,
1907 .release = seq_release,
1908 };
1909
1910 #endif
1911
1912 static void __exit packet_exit(void)
1913 {
1914 proc_net_remove("packet");
1915 unregister_netdevice_notifier(&packet_netdev_notifier);
1916 sock_unregister(PF_PACKET);
1917 proto_unregister(&packet_proto);
1918 }
1919
1920 static int __init packet_init(void)
1921 {
1922 int rc = proto_register(&packet_proto, 0);
1923
1924 if (rc != 0)
1925 goto out;
1926
1927 sock_register(&packet_family_ops);
1928 register_netdevice_notifier(&packet_netdev_notifier);
1929 proc_net_fops_create("packet", 0, &packet_seq_fops);
1930 out:
1931 return rc;
1932 }
1933
1934 module_init(packet_init);
1935 module_exit(packet_exit);
1936 MODULE_LICENSE("GPL");
1937 MODULE_ALIAS_NETPROTO(PF_PACKET);
Stable & featurefull patchset based on Linus's git branch