packet: remove some pointless conditionals before kfree_skb()
[linux-2.6] / net / packet / af_packet.c
1 /*
2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
3  *              operating system.  INET is implemented using the  BSD Socket
4  *              interface as the means of communication with the user level.
5  *
6  *              PACKET - implements raw packet sockets.
7  *
8  * Authors:     Ross Biro
9  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
11  *
12  * Fixes:
13  *              Alan Cox        :       verify_area() now used correctly
14  *              Alan Cox        :       new skbuff lists, look ma no backlogs!
15  *              Alan Cox        :       tidied skbuff lists.
16  *              Alan Cox        :       Now uses generic datagram routines I
17  *                                      added. Also fixed the peek/read crash
18  *                                      from all old Linux datagram code.
19  *              Alan Cox        :       Uses the improved datagram code.
20  *              Alan Cox        :       Added NULL's for socket options.
21  *              Alan Cox        :       Re-commented the code.
22  *              Alan Cox        :       Use new kernel side addressing
23  *              Rob Janssen     :       Correct MTU usage.
24  *              Dave Platt      :       Counter leaks caused by incorrect
25  *                                      interrupt locking and some slightly
26  *                                      dubious gcc output. Can you read
27  *                                      compiler: it said _VOLATILE_
28  *      Richard Kooijman        :       Timestamp fixes.
29  *              Alan Cox        :       New buffers. Use sk->mac.raw.
30  *              Alan Cox        :       sendmsg/recvmsg support.
31  *              Alan Cox        :       Protocol setting support
32  *      Alexey Kuznetsov        :       Untied from IPv4 stack.
33  *      Cyrus Durgin            :       Fixed kerneld for kmod.
34  *      Michal Ostrowski        :       Module initialization cleanup.
35  *         Ulises Alonso        :       Frame number limit removal and
36  *                                      packet_set_ring memory leak.
37  *              Eric Biederman  :       Allow for > 8 byte hardware addresses.
38  *                                      The convention is that longer addresses
39  *                                      will simply extend the hardware address
40  *                                      byte arrays at the end of sockaddr_ll
41  *                                      and packet_mreq.
42  *
43  *              This program is free software; you can redistribute it and/or
44  *              modify it under the terms of the GNU General Public License
45  *              as published by the Free Software Foundation; either version
46  *              2 of the License, or (at your option) any later version.
47  *
48  */
49
50 #include <linux/types.h>
51 #include <linux/mm.h>
52 #include <linux/capability.h>
53 #include <linux/fcntl.h>
54 #include <linux/socket.h>
55 #include <linux/in.h>
56 #include <linux/inet.h>
57 #include <linux/netdevice.h>
58 #include <linux/if_packet.h>
59 #include <linux/wireless.h>
60 #include <linux/kernel.h>
61 #include <linux/kmod.h>
62 #include <net/net_namespace.h>
63 #include <net/ip.h>
64 #include <net/protocol.h>
65 #include <linux/skbuff.h>
66 #include <net/sock.h>
67 #include <linux/errno.h>
68 #include <linux/timer.h>
69 #include <asm/system.h>
70 #include <asm/uaccess.h>
71 #include <asm/ioctls.h>
72 #include <asm/page.h>
73 #include <asm/cacheflush.h>
74 #include <asm/io.h>
75 #include <linux/proc_fs.h>
76 #include <linux/seq_file.h>
77 #include <linux/poll.h>
78 #include <linux/module.h>
79 #include <linux/init.h>
80 #include <linux/mutex.h>
81
82 #ifdef CONFIG_INET
83 #include <net/inet_common.h>
84 #endif
85
86 /*
87    Assumptions:
88    - if device has no dev->hard_header routine, it adds and removes ll header
89      inside itself. In this case ll header is invisible outside of device,
90      but higher levels still should reserve dev->hard_header_len.
91      Some devices are enough clever to reallocate skb, when header
92      will not fit to reserved space (tunnel), another ones are silly
93      (PPP).
94    - packet socket receives packets with pulled ll header,
95      so that SOCK_RAW should push it back.
96
97 On receive:
98 -----------
99
100 Incoming, dev->hard_header!=NULL
101    mac_header -> ll header
102    data       -> data
103
104 Outgoing, dev->hard_header!=NULL
105    mac_header -> ll header
106    data       -> ll header
107
108 Incoming, dev->hard_header==NULL
109    mac_header -> UNKNOWN position. It is very likely, that it points to ll
110                  header.  PPP makes it, that is wrong, because introduce
111                  assymetry between rx and tx paths.
112    data       -> data
113
114 Outgoing, dev->hard_header==NULL
115    mac_header -> data. ll header is still not built!
116    data       -> data
117
118 Resume
119   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
120
121
122 On transmit:
123 ------------
124
125 dev->hard_header != NULL
126    mac_header -> ll header
127    data       -> ll header
128
129 dev->hard_header == NULL (ll header is added by device, we cannot control it)
130    mac_header -> data
131    data       -> data
132
133    We should set nh.raw on output to correct posistion,
134    packet classifier depends on it.
135  */
136
137 /* Private packet socket structures. */
138
139 struct packet_mclist
140 {
141         struct packet_mclist    *next;
142         int                     ifindex;
143         int                     count;
144         unsigned short          type;
145         unsigned short          alen;
146         unsigned char           addr[MAX_ADDR_LEN];
147 };
148 /* identical to struct packet_mreq except it has
149  * a longer address field.
150  */
151 struct packet_mreq_max
152 {
153         int             mr_ifindex;
154         unsigned short  mr_type;
155         unsigned short  mr_alen;
156         unsigned char   mr_address[MAX_ADDR_LEN];
157 };
158
159 #ifdef CONFIG_PACKET_MMAP
160 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
161 #endif
162
163 static void packet_flush_mclist(struct sock *sk);
164
165 struct packet_sock {
166         /* struct sock has to be the first member of packet_sock */
167         struct sock             sk;
168         struct tpacket_stats    stats;
169 #ifdef CONFIG_PACKET_MMAP
170         char *                  *pg_vec;
171         unsigned int            head;
172         unsigned int            frames_per_block;
173         unsigned int            frame_size;
174         unsigned int            frame_max;
175         int                     copy_thresh;
176 #endif
177         struct packet_type      prot_hook;
178         spinlock_t              bind_lock;
179         struct mutex            pg_vec_lock;
180         unsigned int            running:1,      /* prot_hook is attached*/
181                                 auxdata:1,
182                                 origdev:1;
183         int                     ifindex;        /* bound device         */
184         __be16                  num;
185         struct packet_mclist    *mclist;
186 #ifdef CONFIG_PACKET_MMAP
187         atomic_t                mapped;
188         unsigned int            pg_vec_order;
189         unsigned int            pg_vec_pages;
190         unsigned int            pg_vec_len;
191         enum tpacket_versions   tp_version;
192         unsigned int            tp_hdrlen;
193         unsigned int            tp_reserve;
194 #endif
195 };
196
197 struct packet_skb_cb {
198         unsigned int origlen;
199         union {
200                 struct sockaddr_pkt pkt;
201                 struct sockaddr_ll ll;
202         } sa;
203 };
204
205 #define PACKET_SKB_CB(__skb)    ((struct packet_skb_cb *)((__skb)->cb))
206
207 #ifdef CONFIG_PACKET_MMAP
208
209 static void *packet_lookup_frame(struct packet_sock *po, unsigned int position,
210                                  int status)
211 {
212         unsigned int pg_vec_pos, frame_offset;
213         union {
214                 struct tpacket_hdr *h1;
215                 struct tpacket2_hdr *h2;
216                 void *raw;
217         } h;
218
219         pg_vec_pos = position / po->frames_per_block;
220         frame_offset = position % po->frames_per_block;
221
222         h.raw = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
223         switch (po->tp_version) {
224         case TPACKET_V1:
225                 if (status != (h.h1->tp_status ? TP_STATUS_USER :
226                                                 TP_STATUS_KERNEL))
227                         return NULL;
228                 break;
229         case TPACKET_V2:
230                 if (status != (h.h2->tp_status ? TP_STATUS_USER :
231                                                 TP_STATUS_KERNEL))
232                         return NULL;
233                 break;
234         }
235         return h.raw;
236 }
237
238 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
239 {
240         union {
241                 struct tpacket_hdr *h1;
242                 struct tpacket2_hdr *h2;
243                 void *raw;
244         } h;
245
246         h.raw = frame;
247         switch (po->tp_version) {
248         case TPACKET_V1:
249                 h.h1->tp_status = status;
250                 break;
251         case TPACKET_V2:
252                 h.h2->tp_status = status;
253                 break;
254         }
255 }
256 #endif
257
258 static inline struct packet_sock *pkt_sk(struct sock *sk)
259 {
260         return (struct packet_sock *)sk;
261 }
262
263 static void packet_sock_destruct(struct sock *sk)
264 {
265         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
266         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
267
268         if (!sock_flag(sk, SOCK_DEAD)) {
269                 printk("Attempt to release alive packet socket: %p\n", sk);
270                 return;
271         }
272
273         sk_refcnt_debug_dec(sk);
274 }
275
276
277 static const struct proto_ops packet_ops;
278
279 static const struct proto_ops packet_ops_spkt;
280
281 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt, struct net_device *orig_dev)
282 {
283         struct sock *sk;
284         struct sockaddr_pkt *spkt;
285
286         /*
287          *      When we registered the protocol we saved the socket in the data
288          *      field for just this event.
289          */
290
291         sk = pt->af_packet_priv;
292
293         /*
294          *      Yank back the headers [hope the device set this
295          *      right or kerboom...]
296          *
297          *      Incoming packets have ll header pulled,
298          *      push it back.
299          *
300          *      For outgoing ones skb->data == skb_mac_header(skb)
301          *      so that this procedure is noop.
302          */
303
304         if (skb->pkt_type == PACKET_LOOPBACK)
305                 goto out;
306
307         if (dev_net(dev) != sock_net(sk))
308                 goto out;
309
310         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
311                 goto oom;
312
313         /* drop any routing info */
314         dst_release(skb->dst);
315         skb->dst = NULL;
316
317         /* drop conntrack reference */
318         nf_reset(skb);
319
320         spkt = &PACKET_SKB_CB(skb)->sa.pkt;
321
322         skb_push(skb, skb->data - skb_mac_header(skb));
323
324         /*
325          *      The SOCK_PACKET socket receives _all_ frames.
326          */
327
328         spkt->spkt_family = dev->type;
329         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
330         spkt->spkt_protocol = skb->protocol;
331
332         /*
333          *      Charge the memory to the socket. This is done specifically
334          *      to prevent sockets using all the memory up.
335          */
336
337         if (sock_queue_rcv_skb(sk,skb) == 0)
338                 return 0;
339
340 out:
341         kfree_skb(skb);
342 oom:
343         return 0;
344 }
345
346
347 /*
348  *      Output a raw packet to a device layer. This bypasses all the other
349  *      protocol layers and you must therefore supply it with a complete frame
350  */
351
352 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
353                                struct msghdr *msg, size_t len)
354 {
355         struct sock *sk = sock->sk;
356         struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
357         struct sk_buff *skb;
358         struct net_device *dev;
359         __be16 proto=0;
360         int err;
361
362         /*
363          *      Get and verify the address.
364          */
365
366         if (saddr)
367         {
368                 if (msg->msg_namelen < sizeof(struct sockaddr))
369                         return(-EINVAL);
370                 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
371                         proto=saddr->spkt_protocol;
372         }
373         else
374                 return(-ENOTCONN);      /* SOCK_PACKET must be sent giving an address */
375
376         /*
377          *      Find the device first to size check it
378          */
379
380         saddr->spkt_device[13] = 0;
381         dev = dev_get_by_name(sock_net(sk), saddr->spkt_device);
382         err = -ENODEV;
383         if (dev == NULL)
384                 goto out_unlock;
385
386         err = -ENETDOWN;
387         if (!(dev->flags & IFF_UP))
388                 goto out_unlock;
389
390         /*
391          *      You may not queue a frame bigger than the mtu. This is the lowest level
392          *      raw protocol and you must do your own fragmentation at this level.
393          */
394
395         err = -EMSGSIZE;
396         if (len > dev->mtu + dev->hard_header_len)
397                 goto out_unlock;
398
399         err = -ENOBUFS;
400         skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
401
402         /*
403          *      If the write buffer is full, then tough. At this level the user gets to
404          *      deal with the problem - do your own algorithmic backoffs. That's far
405          *      more flexible.
406          */
407
408         if (skb == NULL)
409                 goto out_unlock;
410
411         /*
412          *      Fill it in
413          */
414
415         /* FIXME: Save some space for broken drivers that write a
416          * hard header at transmission time by themselves. PPP is the
417          * notable one here. This should really be fixed at the driver level.
418          */
419         skb_reserve(skb, LL_RESERVED_SPACE(dev));
420         skb_reset_network_header(skb);
421
422         /* Try to align data part correctly */
423         if (dev->header_ops) {
424                 skb->data -= dev->hard_header_len;
425                 skb->tail -= dev->hard_header_len;
426                 if (len < dev->hard_header_len)
427                         skb_reset_network_header(skb);
428         }
429
430         /* Returns -EFAULT on error */
431         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
432         skb->protocol = proto;
433         skb->dev = dev;
434         skb->priority = sk->sk_priority;
435         if (err)
436                 goto out_free;
437
438         /*
439          *      Now send it
440          */
441
442         dev_queue_xmit(skb);
443         dev_put(dev);
444         return(len);
445
446 out_free:
447         kfree_skb(skb);
448 out_unlock:
449         if (dev)
450                 dev_put(dev);
451         return err;
452 }
453
454 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
455                                       unsigned int res)
456 {
457         struct sk_filter *filter;
458
459         rcu_read_lock_bh();
460         filter = rcu_dereference(sk->sk_filter);
461         if (filter != NULL)
462                 res = sk_run_filter(skb, filter->insns, filter->len);
463         rcu_read_unlock_bh();
464
465         return res;
466 }
467
468 /*
469    This function makes lazy skb cloning in hope that most of packets
470    are discarded by BPF.
471
472    Note tricky part: we DO mangle shared skb! skb->data, skb->len
473    and skb->cb are mangled. It works because (and until) packets
474    falling here are owned by current CPU. Output packets are cloned
475    by dev_queue_xmit_nit(), input packets are processed by net_bh
476    sequencially, so that if we return skb to original state on exit,
477    we will not harm anyone.
478  */
479
480 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
481 {
482         struct sock *sk;
483         struct sockaddr_ll *sll;
484         struct packet_sock *po;
485         u8 * skb_head = skb->data;
486         int skb_len = skb->len;
487         unsigned int snaplen, res;
488
489         if (skb->pkt_type == PACKET_LOOPBACK)
490                 goto drop;
491
492         sk = pt->af_packet_priv;
493         po = pkt_sk(sk);
494
495         if (dev_net(dev) != sock_net(sk))
496                 goto drop;
497
498         skb->dev = dev;
499
500         if (dev->header_ops) {
501                 /* The device has an explicit notion of ll header,
502                    exported to higher levels.
503
504                    Otherwise, the device hides datails of it frame
505                    structure, so that corresponding packet head
506                    never delivered to user.
507                  */
508                 if (sk->sk_type != SOCK_DGRAM)
509                         skb_push(skb, skb->data - skb_mac_header(skb));
510                 else if (skb->pkt_type == PACKET_OUTGOING) {
511                         /* Special case: outgoing packets have ll header at head */
512                         skb_pull(skb, skb_network_offset(skb));
513                 }
514         }
515
516         snaplen = skb->len;
517
518         res = run_filter(skb, sk, snaplen);
519         if (!res)
520                 goto drop_n_restore;
521         if (snaplen > res)
522                 snaplen = res;
523
524         if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
525             (unsigned)sk->sk_rcvbuf)
526                 goto drop_n_acct;
527
528         if (skb_shared(skb)) {
529                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
530                 if (nskb == NULL)
531                         goto drop_n_acct;
532
533                 if (skb_head != skb->data) {
534                         skb->data = skb_head;
535                         skb->len = skb_len;
536                 }
537                 kfree_skb(skb);
538                 skb = nskb;
539         }
540
541         BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
542                      sizeof(skb->cb));
543
544         sll = &PACKET_SKB_CB(skb)->sa.ll;
545         sll->sll_family = AF_PACKET;
546         sll->sll_hatype = dev->type;
547         sll->sll_protocol = skb->protocol;
548         sll->sll_pkttype = skb->pkt_type;
549         if (unlikely(po->origdev))
550                 sll->sll_ifindex = orig_dev->ifindex;
551         else
552                 sll->sll_ifindex = dev->ifindex;
553
554         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
555
556         PACKET_SKB_CB(skb)->origlen = skb->len;
557
558         if (pskb_trim(skb, snaplen))
559                 goto drop_n_acct;
560
561         skb_set_owner_r(skb, sk);
562         skb->dev = NULL;
563         dst_release(skb->dst);
564         skb->dst = NULL;
565
566         /* drop conntrack reference */
567         nf_reset(skb);
568
569         spin_lock(&sk->sk_receive_queue.lock);
570         po->stats.tp_packets++;
571         __skb_queue_tail(&sk->sk_receive_queue, skb);
572         spin_unlock(&sk->sk_receive_queue.lock);
573         sk->sk_data_ready(sk, skb->len);
574         return 0;
575
576 drop_n_acct:
577         spin_lock(&sk->sk_receive_queue.lock);
578         po->stats.tp_drops++;
579         spin_unlock(&sk->sk_receive_queue.lock);
580
581 drop_n_restore:
582         if (skb_head != skb->data && skb_shared(skb)) {
583                 skb->data = skb_head;
584                 skb->len = skb_len;
585         }
586 drop:
587         kfree_skb(skb);
588         return 0;
589 }
590
591 #ifdef CONFIG_PACKET_MMAP
592 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
593 {
594         struct sock *sk;
595         struct packet_sock *po;
596         struct sockaddr_ll *sll;
597         union {
598                 struct tpacket_hdr *h1;
599                 struct tpacket2_hdr *h2;
600                 void *raw;
601         } h;
602         u8 * skb_head = skb->data;
603         int skb_len = skb->len;
604         unsigned int snaplen, res;
605         unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
606         unsigned short macoff, netoff, hdrlen;
607         struct sk_buff *copy_skb = NULL;
608         struct timeval tv;
609         struct timespec ts;
610
611         if (skb->pkt_type == PACKET_LOOPBACK)
612                 goto drop;
613
614         sk = pt->af_packet_priv;
615         po = pkt_sk(sk);
616
617         if (dev_net(dev) != sock_net(sk))
618                 goto drop;
619
620         if (dev->header_ops) {
621                 if (sk->sk_type != SOCK_DGRAM)
622                         skb_push(skb, skb->data - skb_mac_header(skb));
623                 else if (skb->pkt_type == PACKET_OUTGOING) {
624                         /* Special case: outgoing packets have ll header at head */
625                         skb_pull(skb, skb_network_offset(skb));
626                 }
627         }
628
629         if (skb->ip_summed == CHECKSUM_PARTIAL)
630                 status |= TP_STATUS_CSUMNOTREADY;
631
632         snaplen = skb->len;
633
634         res = run_filter(skb, sk, snaplen);
635         if (!res)
636                 goto drop_n_restore;
637         if (snaplen > res)
638                 snaplen = res;
639
640         if (sk->sk_type == SOCK_DGRAM) {
641                 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
642                                   po->tp_reserve;
643         } else {
644                 unsigned maclen = skb_network_offset(skb);
645                 netoff = TPACKET_ALIGN(po->tp_hdrlen +
646                                        (maclen < 16 ? 16 : maclen)) +
647                         po->tp_reserve;
648                 macoff = netoff - maclen;
649         }
650
651         if (macoff + snaplen > po->frame_size) {
652                 if (po->copy_thresh &&
653                     atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
654                     (unsigned)sk->sk_rcvbuf) {
655                         if (skb_shared(skb)) {
656                                 copy_skb = skb_clone(skb, GFP_ATOMIC);
657                         } else {
658                                 copy_skb = skb_get(skb);
659                                 skb_head = skb->data;
660                         }
661                         if (copy_skb)
662                                 skb_set_owner_r(copy_skb, sk);
663                 }
664                 snaplen = po->frame_size - macoff;
665                 if ((int)snaplen < 0)
666                         snaplen = 0;
667         }
668
669         spin_lock(&sk->sk_receive_queue.lock);
670         h.raw = packet_lookup_frame(po, po->head, TP_STATUS_KERNEL);
671         if (!h.raw)
672                 goto ring_is_full;
673         po->head = po->head != po->frame_max ? po->head+1 : 0;
674         po->stats.tp_packets++;
675         if (copy_skb) {
676                 status |= TP_STATUS_COPY;
677                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
678         }
679         if (!po->stats.tp_drops)
680                 status &= ~TP_STATUS_LOSING;
681         spin_unlock(&sk->sk_receive_queue.lock);
682
683         skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
684
685         switch (po->tp_version) {
686         case TPACKET_V1:
687                 h.h1->tp_len = skb->len;
688                 h.h1->tp_snaplen = snaplen;
689                 h.h1->tp_mac = macoff;
690                 h.h1->tp_net = netoff;
691                 if (skb->tstamp.tv64)
692                         tv = ktime_to_timeval(skb->tstamp);
693                 else
694                         do_gettimeofday(&tv);
695                 h.h1->tp_sec = tv.tv_sec;
696                 h.h1->tp_usec = tv.tv_usec;
697                 hdrlen = sizeof(*h.h1);
698                 break;
699         case TPACKET_V2:
700                 h.h2->tp_len = skb->len;
701                 h.h2->tp_snaplen = snaplen;
702                 h.h2->tp_mac = macoff;
703                 h.h2->tp_net = netoff;
704                 if (skb->tstamp.tv64)
705                         ts = ktime_to_timespec(skb->tstamp);
706                 else
707                         getnstimeofday(&ts);
708                 h.h2->tp_sec = ts.tv_sec;
709                 h.h2->tp_nsec = ts.tv_nsec;
710                 h.h2->tp_vlan_tci = skb->vlan_tci;
711                 hdrlen = sizeof(*h.h2);
712                 break;
713         default:
714                 BUG();
715         }
716
717         sll = h.raw + TPACKET_ALIGN(hdrlen);
718         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
719         sll->sll_family = AF_PACKET;
720         sll->sll_hatype = dev->type;
721         sll->sll_protocol = skb->protocol;
722         sll->sll_pkttype = skb->pkt_type;
723         if (unlikely(po->origdev))
724                 sll->sll_ifindex = orig_dev->ifindex;
725         else
726                 sll->sll_ifindex = dev->ifindex;
727
728         __packet_set_status(po, h.raw, status);
729         smp_mb();
730
731         {
732                 struct page *p_start, *p_end;
733                 u8 *h_end = h.raw + macoff + snaplen - 1;
734
735                 p_start = virt_to_page(h.raw);
736                 p_end = virt_to_page(h_end);
737                 while (p_start <= p_end) {
738                         flush_dcache_page(p_start);
739                         p_start++;
740                 }
741         }
742
743         sk->sk_data_ready(sk, 0);
744
745 drop_n_restore:
746         if (skb_head != skb->data && skb_shared(skb)) {
747                 skb->data = skb_head;
748                 skb->len = skb_len;
749         }
750 drop:
751         kfree_skb(skb);
752         return 0;
753
754 ring_is_full:
755         po->stats.tp_drops++;
756         spin_unlock(&sk->sk_receive_queue.lock);
757
758         sk->sk_data_ready(sk, 0);
759         kfree_skb(copy_skb);
760         goto drop_n_restore;
761 }
762
763 #endif
764
765
766 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
767                           struct msghdr *msg, size_t len)
768 {
769         struct sock *sk = sock->sk;
770         struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
771         struct sk_buff *skb;
772         struct net_device *dev;
773         __be16 proto;
774         unsigned char *addr;
775         int ifindex, err, reserve = 0;
776
777         /*
778          *      Get and verify the address.
779          */
780
781         if (saddr == NULL) {
782                 struct packet_sock *po = pkt_sk(sk);
783
784                 ifindex = po->ifindex;
785                 proto   = po->num;
786                 addr    = NULL;
787         } else {
788                 err = -EINVAL;
789                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
790                         goto out;
791                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
792                         goto out;
793                 ifindex = saddr->sll_ifindex;
794                 proto   = saddr->sll_protocol;
795                 addr    = saddr->sll_addr;
796         }
797
798
799         dev = dev_get_by_index(sock_net(sk), ifindex);
800         err = -ENXIO;
801         if (dev == NULL)
802                 goto out_unlock;
803         if (sock->type == SOCK_RAW)
804                 reserve = dev->hard_header_len;
805
806         err = -ENETDOWN;
807         if (!(dev->flags & IFF_UP))
808                 goto out_unlock;
809
810         err = -EMSGSIZE;
811         if (len > dev->mtu+reserve)
812                 goto out_unlock;
813
814         skb = sock_alloc_send_skb(sk, len + LL_ALLOCATED_SPACE(dev),
815                                 msg->msg_flags & MSG_DONTWAIT, &err);
816         if (skb==NULL)
817                 goto out_unlock;
818
819         skb_reserve(skb, LL_RESERVED_SPACE(dev));
820         skb_reset_network_header(skb);
821
822         err = -EINVAL;
823         if (sock->type == SOCK_DGRAM &&
824             dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len) < 0)
825                 goto out_free;
826
827         /* Returns -EFAULT on error */
828         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
829         if (err)
830                 goto out_free;
831
832         skb->protocol = proto;
833         skb->dev = dev;
834         skb->priority = sk->sk_priority;
835
836         /*
837          *      Now send it
838          */
839
840         err = dev_queue_xmit(skb);
841         if (err > 0 && (err = net_xmit_errno(err)) != 0)
842                 goto out_unlock;
843
844         dev_put(dev);
845
846         return(len);
847
848 out_free:
849         kfree_skb(skb);
850 out_unlock:
851         if (dev)
852                 dev_put(dev);
853 out:
854         return err;
855 }
856
857 /*
858  *      Close a PACKET socket. This is fairly simple. We immediately go
859  *      to 'closed' state and remove our protocol entry in the device list.
860  */
861
862 static int packet_release(struct socket *sock)
863 {
864         struct sock *sk = sock->sk;
865         struct packet_sock *po;
866         struct net *net;
867
868         if (!sk)
869                 return 0;
870
871         net = sock_net(sk);
872         po = pkt_sk(sk);
873
874         write_lock_bh(&net->packet.sklist_lock);
875         sk_del_node_init(sk);
876         sock_prot_inuse_add(net, sk->sk_prot, -1);
877         write_unlock_bh(&net->packet.sklist_lock);
878
879         /*
880          *      Unhook packet receive handler.
881          */
882
883         if (po->running) {
884                 /*
885                  *      Remove the protocol hook
886                  */
887                 dev_remove_pack(&po->prot_hook);
888                 po->running = 0;
889                 po->num = 0;
890                 __sock_put(sk);
891         }
892
893         packet_flush_mclist(sk);
894
895 #ifdef CONFIG_PACKET_MMAP
896         if (po->pg_vec) {
897                 struct tpacket_req req;
898                 memset(&req, 0, sizeof(req));
899                 packet_set_ring(sk, &req, 1);
900         }
901 #endif
902
903         /*
904          *      Now the socket is dead. No more input will appear.
905          */
906
907         sock_orphan(sk);
908         sock->sk = NULL;
909
910         /* Purge queues */
911
912         skb_queue_purge(&sk->sk_receive_queue);
913         sk_refcnt_debug_release(sk);
914
915         sock_put(sk);
916         return 0;
917 }
918
919 /*
920  *      Attach a packet hook.
921  */
922
923 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
924 {
925         struct packet_sock *po = pkt_sk(sk);
926         /*
927          *      Detach an existing hook if present.
928          */
929
930         lock_sock(sk);
931
932         spin_lock(&po->bind_lock);
933         if (po->running) {
934                 __sock_put(sk);
935                 po->running = 0;
936                 po->num = 0;
937                 spin_unlock(&po->bind_lock);
938                 dev_remove_pack(&po->prot_hook);
939                 spin_lock(&po->bind_lock);
940         }
941
942         po->num = protocol;
943         po->prot_hook.type = protocol;
944         po->prot_hook.dev = dev;
945
946         po->ifindex = dev ? dev->ifindex : 0;
947
948         if (protocol == 0)
949                 goto out_unlock;
950
951         if (!dev || (dev->flags & IFF_UP)) {
952                 dev_add_pack(&po->prot_hook);
953                 sock_hold(sk);
954                 po->running = 1;
955         } else {
956                 sk->sk_err = ENETDOWN;
957                 if (!sock_flag(sk, SOCK_DEAD))
958                         sk->sk_error_report(sk);
959         }
960
961 out_unlock:
962         spin_unlock(&po->bind_lock);
963         release_sock(sk);
964         return 0;
965 }
966
967 /*
968  *      Bind a packet socket to a device
969  */
970
971 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
972 {
973         struct sock *sk=sock->sk;
974         char name[15];
975         struct net_device *dev;
976         int err = -ENODEV;
977
978         /*
979          *      Check legality
980          */
981
982         if (addr_len != sizeof(struct sockaddr))
983                 return -EINVAL;
984         strlcpy(name,uaddr->sa_data,sizeof(name));
985
986         dev = dev_get_by_name(sock_net(sk), name);
987         if (dev) {
988                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
989                 dev_put(dev);
990         }
991         return err;
992 }
993
994 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
995 {
996         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
997         struct sock *sk=sock->sk;
998         struct net_device *dev = NULL;
999         int err;
1000
1001
1002         /*
1003          *      Check legality
1004          */
1005
1006         if (addr_len < sizeof(struct sockaddr_ll))
1007                 return -EINVAL;
1008         if (sll->sll_family != AF_PACKET)
1009                 return -EINVAL;
1010
1011         if (sll->sll_ifindex) {
1012                 err = -ENODEV;
1013                 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1014                 if (dev == NULL)
1015                         goto out;
1016         }
1017         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1018         if (dev)
1019                 dev_put(dev);
1020
1021 out:
1022         return err;
1023 }
1024
1025 static struct proto packet_proto = {
1026         .name     = "PACKET",
1027         .owner    = THIS_MODULE,
1028         .obj_size = sizeof(struct packet_sock),
1029 };
1030
1031 /*
1032  *      Create a packet of type SOCK_PACKET.
1033  */
1034
1035 static int packet_create(struct net *net, struct socket *sock, int protocol)
1036 {
1037         struct sock *sk;
1038         struct packet_sock *po;
1039         __be16 proto = (__force __be16)protocol; /* weird, but documented */
1040         int err;
1041
1042         if (!capable(CAP_NET_RAW))
1043                 return -EPERM;
1044         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1045             sock->type != SOCK_PACKET)
1046                 return -ESOCKTNOSUPPORT;
1047
1048         sock->state = SS_UNCONNECTED;
1049
1050         err = -ENOBUFS;
1051         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1052         if (sk == NULL)
1053                 goto out;
1054
1055         sock->ops = &packet_ops;
1056         if (sock->type == SOCK_PACKET)
1057                 sock->ops = &packet_ops_spkt;
1058
1059         sock_init_data(sock, sk);
1060
1061         po = pkt_sk(sk);
1062         sk->sk_family = PF_PACKET;
1063         po->num = proto;
1064
1065         sk->sk_destruct = packet_sock_destruct;
1066         sk_refcnt_debug_inc(sk);
1067
1068         /*
1069          *      Attach a protocol block
1070          */
1071
1072         spin_lock_init(&po->bind_lock);
1073         mutex_init(&po->pg_vec_lock);
1074         po->prot_hook.func = packet_rcv;
1075
1076         if (sock->type == SOCK_PACKET)
1077                 po->prot_hook.func = packet_rcv_spkt;
1078
1079         po->prot_hook.af_packet_priv = sk;
1080
1081         if (proto) {
1082                 po->prot_hook.type = proto;
1083                 dev_add_pack(&po->prot_hook);
1084                 sock_hold(sk);
1085                 po->running = 1;
1086         }
1087
1088         write_lock_bh(&net->packet.sklist_lock);
1089         sk_add_node(sk, &net->packet.sklist);
1090         sock_prot_inuse_add(net, &packet_proto, 1);
1091         write_unlock_bh(&net->packet.sklist_lock);
1092         return(0);
1093 out:
1094         return err;
1095 }
1096
1097 /*
1098  *      Pull a packet from our receive queue and hand it to the user.
1099  *      If necessary we block.
1100  */
1101
1102 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1103                           struct msghdr *msg, size_t len, int flags)
1104 {
1105         struct sock *sk = sock->sk;
1106         struct sk_buff *skb;
1107         int copied, err;
1108         struct sockaddr_ll *sll;
1109
1110         err = -EINVAL;
1111         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1112                 goto out;
1113
1114 #if 0
1115         /* What error should we return now? EUNATTACH? */
1116         if (pkt_sk(sk)->ifindex < 0)
1117                 return -ENODEV;
1118 #endif
1119
1120         /*
1121          *      Call the generic datagram receiver. This handles all sorts
1122          *      of horrible races and re-entrancy so we can forget about it
1123          *      in the protocol layers.
1124          *
1125          *      Now it will return ENETDOWN, if device have just gone down,
1126          *      but then it will block.
1127          */
1128
1129         skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1130
1131         /*
1132          *      An error occurred so return it. Because skb_recv_datagram()
1133          *      handles the blocking we don't see and worry about blocking
1134          *      retries.
1135          */
1136
1137         if (skb == NULL)
1138                 goto out;
1139
1140         /*
1141          *      If the address length field is there to be filled in, we fill
1142          *      it in now.
1143          */
1144
1145         sll = &PACKET_SKB_CB(skb)->sa.ll;
1146         if (sock->type == SOCK_PACKET)
1147                 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1148         else
1149                 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1150
1151         /*
1152          *      You lose any data beyond the buffer you gave. If it worries a
1153          *      user program they can ask the device for its MTU anyway.
1154          */
1155
1156         copied = skb->len;
1157         if (copied > len)
1158         {
1159                 copied=len;
1160                 msg->msg_flags|=MSG_TRUNC;
1161         }
1162
1163         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1164         if (err)
1165                 goto out_free;
1166
1167         sock_recv_timestamp(msg, sk, skb);
1168
1169         if (msg->msg_name)
1170                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1171                        msg->msg_namelen);
1172
1173         if (pkt_sk(sk)->auxdata) {
1174                 struct tpacket_auxdata aux;
1175
1176                 aux.tp_status = TP_STATUS_USER;
1177                 if (skb->ip_summed == CHECKSUM_PARTIAL)
1178                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1179                 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1180                 aux.tp_snaplen = skb->len;
1181                 aux.tp_mac = 0;
1182                 aux.tp_net = skb_network_offset(skb);
1183                 aux.tp_vlan_tci = skb->vlan_tci;
1184
1185                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1186         }
1187
1188         /*
1189          *      Free or return the buffer as appropriate. Again this
1190          *      hides all the races and re-entrancy issues from us.
1191          */
1192         err = (flags&MSG_TRUNC) ? skb->len : copied;
1193
1194 out_free:
1195         skb_free_datagram(sk, skb);
1196 out:
1197         return err;
1198 }
1199
1200 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1201                                int *uaddr_len, int peer)
1202 {
1203         struct net_device *dev;
1204         struct sock *sk = sock->sk;
1205
1206         if (peer)
1207                 return -EOPNOTSUPP;
1208
1209         uaddr->sa_family = AF_PACKET;
1210         dev = dev_get_by_index(sock_net(sk), pkt_sk(sk)->ifindex);
1211         if (dev) {
1212                 strlcpy(uaddr->sa_data, dev->name, 15);
1213                 dev_put(dev);
1214         } else
1215                 memset(uaddr->sa_data, 0, 14);
1216         *uaddr_len = sizeof(*uaddr);
1217
1218         return 0;
1219 }
1220
1221 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1222                           int *uaddr_len, int peer)
1223 {
1224         struct net_device *dev;
1225         struct sock *sk = sock->sk;
1226         struct packet_sock *po = pkt_sk(sk);
1227         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1228
1229         if (peer)
1230                 return -EOPNOTSUPP;
1231
1232         sll->sll_family = AF_PACKET;
1233         sll->sll_ifindex = po->ifindex;
1234         sll->sll_protocol = po->num;
1235         dev = dev_get_by_index(sock_net(sk), po->ifindex);
1236         if (dev) {
1237                 sll->sll_hatype = dev->type;
1238                 sll->sll_halen = dev->addr_len;
1239                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1240                 dev_put(dev);
1241         } else {
1242                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
1243                 sll->sll_halen = 0;
1244         }
1245         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1246
1247         return 0;
1248 }
1249
1250 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
1251                          int what)
1252 {
1253         switch (i->type) {
1254         case PACKET_MR_MULTICAST:
1255                 if (what > 0)
1256                         dev_mc_add(dev, i->addr, i->alen, 0);
1257                 else
1258                         dev_mc_delete(dev, i->addr, i->alen, 0);
1259                 break;
1260         case PACKET_MR_PROMISC:
1261                 return dev_set_promiscuity(dev, what);
1262                 break;
1263         case PACKET_MR_ALLMULTI:
1264                 return dev_set_allmulti(dev, what);
1265                 break;
1266         default:;
1267         }
1268         return 0;
1269 }
1270
1271 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1272 {
1273         for ( ; i; i=i->next) {
1274                 if (i->ifindex == dev->ifindex)
1275                         packet_dev_mc(dev, i, what);
1276         }
1277 }
1278
1279 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1280 {
1281         struct packet_sock *po = pkt_sk(sk);
1282         struct packet_mclist *ml, *i;
1283         struct net_device *dev;
1284         int err;
1285
1286         rtnl_lock();
1287
1288         err = -ENODEV;
1289         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
1290         if (!dev)
1291                 goto done;
1292
1293         err = -EINVAL;
1294         if (mreq->mr_alen > dev->addr_len)
1295                 goto done;
1296
1297         err = -ENOBUFS;
1298         i = kmalloc(sizeof(*i), GFP_KERNEL);
1299         if (i == NULL)
1300                 goto done;
1301
1302         err = 0;
1303         for (ml = po->mclist; ml; ml = ml->next) {
1304                 if (ml->ifindex == mreq->mr_ifindex &&
1305                     ml->type == mreq->mr_type &&
1306                     ml->alen == mreq->mr_alen &&
1307                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1308                         ml->count++;
1309                         /* Free the new element ... */
1310                         kfree(i);
1311                         goto done;
1312                 }
1313         }
1314
1315         i->type = mreq->mr_type;
1316         i->ifindex = mreq->mr_ifindex;
1317         i->alen = mreq->mr_alen;
1318         memcpy(i->addr, mreq->mr_address, i->alen);
1319         i->count = 1;
1320         i->next = po->mclist;
1321         po->mclist = i;
1322         err = packet_dev_mc(dev, i, 1);
1323         if (err) {
1324                 po->mclist = i->next;
1325                 kfree(i);
1326         }
1327
1328 done:
1329         rtnl_unlock();
1330         return err;
1331 }
1332
1333 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1334 {
1335         struct packet_mclist *ml, **mlp;
1336
1337         rtnl_lock();
1338
1339         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1340                 if (ml->ifindex == mreq->mr_ifindex &&
1341                     ml->type == mreq->mr_type &&
1342                     ml->alen == mreq->mr_alen &&
1343                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1344                         if (--ml->count == 0) {
1345                                 struct net_device *dev;
1346                                 *mlp = ml->next;
1347                                 dev = dev_get_by_index(sock_net(sk), ml->ifindex);
1348                                 if (dev) {
1349                                         packet_dev_mc(dev, ml, -1);
1350                                         dev_put(dev);
1351                                 }
1352                                 kfree(ml);
1353                         }
1354                         rtnl_unlock();
1355                         return 0;
1356                 }
1357         }
1358         rtnl_unlock();
1359         return -EADDRNOTAVAIL;
1360 }
1361
1362 static void packet_flush_mclist(struct sock *sk)
1363 {
1364         struct packet_sock *po = pkt_sk(sk);
1365         struct packet_mclist *ml;
1366
1367         if (!po->mclist)
1368                 return;
1369
1370         rtnl_lock();
1371         while ((ml = po->mclist) != NULL) {
1372                 struct net_device *dev;
1373
1374                 po->mclist = ml->next;
1375                 if ((dev = dev_get_by_index(sock_net(sk), ml->ifindex)) != NULL) {
1376                         packet_dev_mc(dev, ml, -1);
1377                         dev_put(dev);
1378                 }
1379                 kfree(ml);
1380         }
1381         rtnl_unlock();
1382 }
1383
1384 static int
1385 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1386 {
1387         struct sock *sk = sock->sk;
1388         struct packet_sock *po = pkt_sk(sk);
1389         int ret;
1390
1391         if (level != SOL_PACKET)
1392                 return -ENOPROTOOPT;
1393
1394         switch(optname) {
1395         case PACKET_ADD_MEMBERSHIP:
1396         case PACKET_DROP_MEMBERSHIP:
1397         {
1398                 struct packet_mreq_max mreq;
1399                 int len = optlen;
1400                 memset(&mreq, 0, sizeof(mreq));
1401                 if (len < sizeof(struct packet_mreq))
1402                         return -EINVAL;
1403                 if (len > sizeof(mreq))
1404                         len = sizeof(mreq);
1405                 if (copy_from_user(&mreq,optval,len))
1406                         return -EFAULT;
1407                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1408                         return -EINVAL;
1409                 if (optname == PACKET_ADD_MEMBERSHIP)
1410                         ret = packet_mc_add(sk, &mreq);
1411                 else
1412                         ret = packet_mc_drop(sk, &mreq);
1413                 return ret;
1414         }
1415
1416 #ifdef CONFIG_PACKET_MMAP
1417         case PACKET_RX_RING:
1418         {
1419                 struct tpacket_req req;
1420
1421                 if (optlen<sizeof(req))
1422                         return -EINVAL;
1423                 if (copy_from_user(&req,optval,sizeof(req)))
1424                         return -EFAULT;
1425                 return packet_set_ring(sk, &req, 0);
1426         }
1427         case PACKET_COPY_THRESH:
1428         {
1429                 int val;
1430
1431                 if (optlen!=sizeof(val))
1432                         return -EINVAL;
1433                 if (copy_from_user(&val,optval,sizeof(val)))
1434                         return -EFAULT;
1435
1436                 pkt_sk(sk)->copy_thresh = val;
1437                 return 0;
1438         }
1439         case PACKET_VERSION:
1440         {
1441                 int val;
1442
1443                 if (optlen != sizeof(val))
1444                         return -EINVAL;
1445                 if (po->pg_vec)
1446                         return -EBUSY;
1447                 if (copy_from_user(&val, optval, sizeof(val)))
1448                         return -EFAULT;
1449                 switch (val) {
1450                 case TPACKET_V1:
1451                 case TPACKET_V2:
1452                         po->tp_version = val;
1453                         return 0;
1454                 default:
1455                         return -EINVAL;
1456                 }
1457         }
1458         case PACKET_RESERVE:
1459         {
1460                 unsigned int val;
1461
1462                 if (optlen != sizeof(val))
1463                         return -EINVAL;
1464                 if (po->pg_vec)
1465                         return -EBUSY;
1466                 if (copy_from_user(&val, optval, sizeof(val)))
1467                         return -EFAULT;
1468                 po->tp_reserve = val;
1469                 return 0;
1470         }
1471 #endif
1472         case PACKET_AUXDATA:
1473         {
1474                 int val;
1475
1476                 if (optlen < sizeof(val))
1477                         return -EINVAL;
1478                 if (copy_from_user(&val, optval, sizeof(val)))
1479                         return -EFAULT;
1480
1481                 po->auxdata = !!val;
1482                 return 0;
1483         }
1484         case PACKET_ORIGDEV:
1485         {
1486                 int val;
1487
1488                 if (optlen < sizeof(val))
1489                         return -EINVAL;
1490                 if (copy_from_user(&val, optval, sizeof(val)))
1491                         return -EFAULT;
1492
1493                 po->origdev = !!val;
1494                 return 0;
1495         }
1496         default:
1497                 return -ENOPROTOOPT;
1498         }
1499 }
1500
1501 static int packet_getsockopt(struct socket *sock, int level, int optname,
1502                              char __user *optval, int __user *optlen)
1503 {
1504         int len;
1505         int val;
1506         struct sock *sk = sock->sk;
1507         struct packet_sock *po = pkt_sk(sk);
1508         void *data;
1509         struct tpacket_stats st;
1510
1511         if (level != SOL_PACKET)
1512                 return -ENOPROTOOPT;
1513
1514         if (get_user(len, optlen))
1515                 return -EFAULT;
1516
1517         if (len < 0)
1518                 return -EINVAL;
1519
1520         switch(optname) {
1521         case PACKET_STATISTICS:
1522                 if (len > sizeof(struct tpacket_stats))
1523                         len = sizeof(struct tpacket_stats);
1524                 spin_lock_bh(&sk->sk_receive_queue.lock);
1525                 st = po->stats;
1526                 memset(&po->stats, 0, sizeof(st));
1527                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1528                 st.tp_packets += st.tp_drops;
1529
1530                 data = &st;
1531                 break;
1532         case PACKET_AUXDATA:
1533                 if (len > sizeof(int))
1534                         len = sizeof(int);
1535                 val = po->auxdata;
1536
1537                 data = &val;
1538                 break;
1539         case PACKET_ORIGDEV:
1540                 if (len > sizeof(int))
1541                         len = sizeof(int);
1542                 val = po->origdev;
1543
1544                 data = &val;
1545                 break;
1546 #ifdef CONFIG_PACKET_MMAP
1547         case PACKET_VERSION:
1548                 if (len > sizeof(int))
1549                         len = sizeof(int);
1550                 val = po->tp_version;
1551                 data = &val;
1552                 break;
1553         case PACKET_HDRLEN:
1554                 if (len > sizeof(int))
1555                         len = sizeof(int);
1556                 if (copy_from_user(&val, optval, len))
1557                         return -EFAULT;
1558                 switch (val) {
1559                 case TPACKET_V1:
1560                         val = sizeof(struct tpacket_hdr);
1561                         break;
1562                 case TPACKET_V2:
1563                         val = sizeof(struct tpacket2_hdr);
1564                         break;
1565                 default:
1566                         return -EINVAL;
1567                 }
1568                 data = &val;
1569                 break;
1570         case PACKET_RESERVE:
1571                 if (len > sizeof(unsigned int))
1572                         len = sizeof(unsigned int);
1573                 val = po->tp_reserve;
1574                 data = &val;
1575                 break;
1576 #endif
1577         default:
1578                 return -ENOPROTOOPT;
1579         }
1580
1581         if (put_user(len, optlen))
1582                 return -EFAULT;
1583         if (copy_to_user(optval, data, len))
1584                 return -EFAULT;
1585         return 0;
1586 }
1587
1588
1589 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1590 {
1591         struct sock *sk;
1592         struct hlist_node *node;
1593         struct net_device *dev = data;
1594         struct net *net = dev_net(dev);
1595
1596         read_lock(&net->packet.sklist_lock);
1597         sk_for_each(sk, node, &net->packet.sklist) {
1598                 struct packet_sock *po = pkt_sk(sk);
1599
1600                 switch (msg) {
1601                 case NETDEV_UNREGISTER:
1602                         if (po->mclist)
1603                                 packet_dev_mclist(dev, po->mclist, -1);
1604                         /* fallthrough */
1605
1606                 case NETDEV_DOWN:
1607                         if (dev->ifindex == po->ifindex) {
1608                                 spin_lock(&po->bind_lock);
1609                                 if (po->running) {
1610                                         __dev_remove_pack(&po->prot_hook);
1611                                         __sock_put(sk);
1612                                         po->running = 0;
1613                                         sk->sk_err = ENETDOWN;
1614                                         if (!sock_flag(sk, SOCK_DEAD))
1615                                                 sk->sk_error_report(sk);
1616                                 }
1617                                 if (msg == NETDEV_UNREGISTER) {
1618                                         po->ifindex = -1;
1619                                         po->prot_hook.dev = NULL;
1620                                 }
1621                                 spin_unlock(&po->bind_lock);
1622                         }
1623                         break;
1624                 case NETDEV_UP:
1625                         spin_lock(&po->bind_lock);
1626                         if (dev->ifindex == po->ifindex && po->num &&
1627                             !po->running) {
1628                                 dev_add_pack(&po->prot_hook);
1629                                 sock_hold(sk);
1630                                 po->running = 1;
1631                         }
1632                         spin_unlock(&po->bind_lock);
1633                         break;
1634                 }
1635         }
1636         read_unlock(&net->packet.sklist_lock);
1637         return NOTIFY_DONE;
1638 }
1639
1640
1641 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1642                         unsigned long arg)
1643 {
1644         struct sock *sk = sock->sk;
1645
1646         switch(cmd) {
1647                 case SIOCOUTQ:
1648                 {
1649                         int amount = atomic_read(&sk->sk_wmem_alloc);
1650                         return put_user(amount, (int __user *)arg);
1651                 }
1652                 case SIOCINQ:
1653                 {
1654                         struct sk_buff *skb;
1655                         int amount = 0;
1656
1657                         spin_lock_bh(&sk->sk_receive_queue.lock);
1658                         skb = skb_peek(&sk->sk_receive_queue);
1659                         if (skb)
1660                                 amount = skb->len;
1661                         spin_unlock_bh(&sk->sk_receive_queue.lock);
1662                         return put_user(amount, (int __user *)arg);
1663                 }
1664                 case SIOCGSTAMP:
1665                         return sock_get_timestamp(sk, (struct timeval __user *)arg);
1666                 case SIOCGSTAMPNS:
1667                         return sock_get_timestampns(sk, (struct timespec __user *)arg);
1668
1669 #ifdef CONFIG_INET
1670                 case SIOCADDRT:
1671                 case SIOCDELRT:
1672                 case SIOCDARP:
1673                 case SIOCGARP:
1674                 case SIOCSARP:
1675                 case SIOCGIFADDR:
1676                 case SIOCSIFADDR:
1677                 case SIOCGIFBRDADDR:
1678                 case SIOCSIFBRDADDR:
1679                 case SIOCGIFNETMASK:
1680                 case SIOCSIFNETMASK:
1681                 case SIOCGIFDSTADDR:
1682                 case SIOCSIFDSTADDR:
1683                 case SIOCSIFFLAGS:
1684                         if (!net_eq(sock_net(sk), &init_net))
1685                                 return -ENOIOCTLCMD;
1686                         return inet_dgram_ops.ioctl(sock, cmd, arg);
1687 #endif
1688
1689                 default:
1690                         return -ENOIOCTLCMD;
1691         }
1692         return 0;
1693 }
1694
1695 #ifndef CONFIG_PACKET_MMAP
1696 #define packet_mmap sock_no_mmap
1697 #define packet_poll datagram_poll
1698 #else
1699
1700 static unsigned int packet_poll(struct file * file, struct socket *sock,
1701                                 poll_table *wait)
1702 {
1703         struct sock *sk = sock->sk;
1704         struct packet_sock *po = pkt_sk(sk);
1705         unsigned int mask = datagram_poll(file, sock, wait);
1706
1707         spin_lock_bh(&sk->sk_receive_queue.lock);
1708         if (po->pg_vec) {
1709                 unsigned last = po->head ? po->head-1 : po->frame_max;
1710
1711                 if (packet_lookup_frame(po, last, TP_STATUS_USER))
1712                         mask |= POLLIN | POLLRDNORM;
1713         }
1714         spin_unlock_bh(&sk->sk_receive_queue.lock);
1715         return mask;
1716 }
1717
1718
1719 /* Dirty? Well, I still did not learn better way to account
1720  * for user mmaps.
1721  */
1722
1723 static void packet_mm_open(struct vm_area_struct *vma)
1724 {
1725         struct file *file = vma->vm_file;
1726         struct socket * sock = file->private_data;
1727         struct sock *sk = sock->sk;
1728
1729         if (sk)
1730                 atomic_inc(&pkt_sk(sk)->mapped);
1731 }
1732
1733 static void packet_mm_close(struct vm_area_struct *vma)
1734 {
1735         struct file *file = vma->vm_file;
1736         struct socket * sock = file->private_data;
1737         struct sock *sk = sock->sk;
1738
1739         if (sk)
1740                 atomic_dec(&pkt_sk(sk)->mapped);
1741 }
1742
1743 static struct vm_operations_struct packet_mmap_ops = {
1744         .open = packet_mm_open,
1745         .close =packet_mm_close,
1746 };
1747
1748 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
1749 {
1750         int i;
1751
1752         for (i = 0; i < len; i++) {
1753                 if (likely(pg_vec[i]))
1754                         free_pages((unsigned long) pg_vec[i], order);
1755         }
1756         kfree(pg_vec);
1757 }
1758
1759 static inline char *alloc_one_pg_vec_page(unsigned long order)
1760 {
1761         return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
1762                                          order);
1763 }
1764
1765 static char **alloc_pg_vec(struct tpacket_req *req, int order)
1766 {
1767         unsigned int block_nr = req->tp_block_nr;
1768         char **pg_vec;
1769         int i;
1770
1771         pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
1772         if (unlikely(!pg_vec))
1773                 goto out;
1774
1775         for (i = 0; i < block_nr; i++) {
1776                 pg_vec[i] = alloc_one_pg_vec_page(order);
1777                 if (unlikely(!pg_vec[i]))
1778                         goto out_free_pgvec;
1779         }
1780
1781 out:
1782         return pg_vec;
1783
1784 out_free_pgvec:
1785         free_pg_vec(pg_vec, order, block_nr);
1786         pg_vec = NULL;
1787         goto out;
1788 }
1789
1790 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1791 {
1792         char **pg_vec = NULL;
1793         struct packet_sock *po = pkt_sk(sk);
1794         int was_running, order = 0;
1795         __be16 num;
1796         int err = 0;
1797
1798         if (req->tp_block_nr) {
1799                 int i;
1800
1801                 /* Sanity tests and some calculations */
1802
1803                 if (unlikely(po->pg_vec))
1804                         return -EBUSY;
1805
1806                 switch (po->tp_version) {
1807                 case TPACKET_V1:
1808                         po->tp_hdrlen = TPACKET_HDRLEN;
1809                         break;
1810                 case TPACKET_V2:
1811                         po->tp_hdrlen = TPACKET2_HDRLEN;
1812                         break;
1813                 }
1814
1815                 if (unlikely((int)req->tp_block_size <= 0))
1816                         return -EINVAL;
1817                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
1818                         return -EINVAL;
1819                 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
1820                                                   po->tp_reserve))
1821                         return -EINVAL;
1822                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
1823                         return -EINVAL;
1824
1825                 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1826                 if (unlikely(po->frames_per_block <= 0))
1827                         return -EINVAL;
1828                 if (unlikely((po->frames_per_block * req->tp_block_nr) !=
1829                              req->tp_frame_nr))
1830                         return -EINVAL;
1831
1832                 err = -ENOMEM;
1833                 order = get_order(req->tp_block_size);
1834                 pg_vec = alloc_pg_vec(req, order);
1835                 if (unlikely(!pg_vec))
1836                         goto out;
1837
1838                 for (i = 0; i < req->tp_block_nr; i++) {
1839                         void *ptr = pg_vec[i];
1840                         int k;
1841
1842                         for (k = 0; k < po->frames_per_block; k++) {
1843                                 __packet_set_status(po, ptr, TP_STATUS_KERNEL);
1844                                 ptr += req->tp_frame_size;
1845                         }
1846                 }
1847                 /* Done */
1848         } else {
1849                 if (unlikely(req->tp_frame_nr))
1850                         return -EINVAL;
1851         }
1852
1853         lock_sock(sk);
1854
1855         /* Detach socket from network */
1856         spin_lock(&po->bind_lock);
1857         was_running = po->running;
1858         num = po->num;
1859         if (was_running) {
1860                 __dev_remove_pack(&po->prot_hook);
1861                 po->num = 0;
1862                 po->running = 0;
1863                 __sock_put(sk);
1864         }
1865         spin_unlock(&po->bind_lock);
1866
1867         synchronize_net();
1868
1869         err = -EBUSY;
1870         mutex_lock(&po->pg_vec_lock);
1871         if (closing || atomic_read(&po->mapped) == 0) {
1872                 err = 0;
1873 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1874
1875                 spin_lock_bh(&sk->sk_receive_queue.lock);
1876                 pg_vec = XC(po->pg_vec, pg_vec);
1877                 po->frame_max = (req->tp_frame_nr - 1);
1878                 po->head = 0;
1879                 po->frame_size = req->tp_frame_size;
1880                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1881
1882                 order = XC(po->pg_vec_order, order);
1883                 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1884
1885                 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1886                 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1887                 skb_queue_purge(&sk->sk_receive_queue);
1888 #undef XC
1889                 if (atomic_read(&po->mapped))
1890                         printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1891         }
1892         mutex_unlock(&po->pg_vec_lock);
1893
1894         spin_lock(&po->bind_lock);
1895         if (was_running && !po->running) {
1896                 sock_hold(sk);
1897                 po->running = 1;
1898                 po->num = num;
1899                 dev_add_pack(&po->prot_hook);
1900         }
1901         spin_unlock(&po->bind_lock);
1902
1903         release_sock(sk);
1904
1905         if (pg_vec)
1906                 free_pg_vec(pg_vec, order, req->tp_block_nr);
1907 out:
1908         return err;
1909 }
1910
1911 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1912 {
1913         struct sock *sk = sock->sk;
1914         struct packet_sock *po = pkt_sk(sk);
1915         unsigned long size;
1916         unsigned long start;
1917         int err = -EINVAL;
1918         int i;
1919
1920         if (vma->vm_pgoff)
1921                 return -EINVAL;
1922
1923         size = vma->vm_end - vma->vm_start;
1924
1925         mutex_lock(&po->pg_vec_lock);
1926         if (po->pg_vec == NULL)
1927                 goto out;
1928         if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1929                 goto out;
1930
1931         start = vma->vm_start;
1932         for (i = 0; i < po->pg_vec_len; i++) {
1933                 struct page *page = virt_to_page(po->pg_vec[i]);
1934                 int pg_num;
1935
1936                 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
1937                         err = vm_insert_page(vma, start, page);
1938                         if (unlikely(err))
1939                                 goto out;
1940                         start += PAGE_SIZE;
1941                 }
1942         }
1943         atomic_inc(&po->mapped);
1944         vma->vm_ops = &packet_mmap_ops;
1945         err = 0;
1946
1947 out:
1948         mutex_unlock(&po->pg_vec_lock);
1949         return err;
1950 }
1951 #endif
1952
1953
1954 static const struct proto_ops packet_ops_spkt = {
1955         .family =       PF_PACKET,
1956         .owner =        THIS_MODULE,
1957         .release =      packet_release,
1958         .bind =         packet_bind_spkt,
1959         .connect =      sock_no_connect,
1960         .socketpair =   sock_no_socketpair,
1961         .accept =       sock_no_accept,
1962         .getname =      packet_getname_spkt,
1963         .poll =         datagram_poll,
1964         .ioctl =        packet_ioctl,
1965         .listen =       sock_no_listen,
1966         .shutdown =     sock_no_shutdown,
1967         .setsockopt =   sock_no_setsockopt,
1968         .getsockopt =   sock_no_getsockopt,
1969         .sendmsg =      packet_sendmsg_spkt,
1970         .recvmsg =      packet_recvmsg,
1971         .mmap =         sock_no_mmap,
1972         .sendpage =     sock_no_sendpage,
1973 };
1974
1975 static const struct proto_ops packet_ops = {
1976         .family =       PF_PACKET,
1977         .owner =        THIS_MODULE,
1978         .release =      packet_release,
1979         .bind =         packet_bind,
1980         .connect =      sock_no_connect,
1981         .socketpair =   sock_no_socketpair,
1982         .accept =       sock_no_accept,
1983         .getname =      packet_getname,
1984         .poll =         packet_poll,
1985         .ioctl =        packet_ioctl,
1986         .listen =       sock_no_listen,
1987         .shutdown =     sock_no_shutdown,
1988         .setsockopt =   packet_setsockopt,
1989         .getsockopt =   packet_getsockopt,
1990         .sendmsg =      packet_sendmsg,
1991         .recvmsg =      packet_recvmsg,
1992         .mmap =         packet_mmap,
1993         .sendpage =     sock_no_sendpage,
1994 };
1995
1996 static struct net_proto_family packet_family_ops = {
1997         .family =       PF_PACKET,
1998         .create =       packet_create,
1999         .owner  =       THIS_MODULE,
2000 };
2001
2002 static struct notifier_block packet_netdev_notifier = {
2003         .notifier_call =packet_notifier,
2004 };
2005
2006 #ifdef CONFIG_PROC_FS
2007 static inline struct sock *packet_seq_idx(struct net *net, loff_t off)
2008 {
2009         struct sock *s;
2010         struct hlist_node *node;
2011
2012         sk_for_each(s, node, &net->packet.sklist) {
2013                 if (!off--)
2014                         return s;
2015         }
2016         return NULL;
2017 }
2018
2019 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2020         __acquires(seq_file_net(seq)->packet.sklist_lock)
2021 {
2022         struct net *net = seq_file_net(seq);
2023         read_lock(&net->packet.sklist_lock);
2024         return *pos ? packet_seq_idx(net, *pos - 1) : SEQ_START_TOKEN;
2025 }
2026
2027 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2028 {
2029         struct net *net = seq_file_net(seq);
2030         ++*pos;
2031         return  (v == SEQ_START_TOKEN)
2032                 ? sk_head(&net->packet.sklist)
2033                 : sk_next((struct sock*)v) ;
2034 }
2035
2036 static void packet_seq_stop(struct seq_file *seq, void *v)
2037         __releases(seq_file_net(seq)->packet.sklist_lock)
2038 {
2039         struct net *net = seq_file_net(seq);
2040         read_unlock(&net->packet.sklist_lock);
2041 }
2042
2043 static int packet_seq_show(struct seq_file *seq, void *v)
2044 {
2045         if (v == SEQ_START_TOKEN)
2046                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
2047         else {
2048                 struct sock *s = v;
2049                 const struct packet_sock *po = pkt_sk(s);
2050
2051                 seq_printf(seq,
2052                            "%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
2053                            s,
2054                            atomic_read(&s->sk_refcnt),
2055                            s->sk_type,
2056                            ntohs(po->num),
2057                            po->ifindex,
2058                            po->running,
2059                            atomic_read(&s->sk_rmem_alloc),
2060                            sock_i_uid(s),
2061                            sock_i_ino(s) );
2062         }
2063
2064         return 0;
2065 }
2066
2067 static const struct seq_operations packet_seq_ops = {
2068         .start  = packet_seq_start,
2069         .next   = packet_seq_next,
2070         .stop   = packet_seq_stop,
2071         .show   = packet_seq_show,
2072 };
2073
2074 static int packet_seq_open(struct inode *inode, struct file *file)
2075 {
2076         return seq_open_net(inode, file, &packet_seq_ops,
2077                             sizeof(struct seq_net_private));
2078 }
2079
2080 static const struct file_operations packet_seq_fops = {
2081         .owner          = THIS_MODULE,
2082         .open           = packet_seq_open,
2083         .read           = seq_read,
2084         .llseek         = seq_lseek,
2085         .release        = seq_release_net,
2086 };
2087
2088 #endif
2089
2090 static int packet_net_init(struct net *net)
2091 {
2092         rwlock_init(&net->packet.sklist_lock);
2093         INIT_HLIST_HEAD(&net->packet.sklist);
2094
2095         if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
2096                 return -ENOMEM;
2097
2098         return 0;
2099 }
2100
2101 static void packet_net_exit(struct net *net)
2102 {
2103         proc_net_remove(net, "packet");
2104 }
2105
2106 static struct pernet_operations packet_net_ops = {
2107         .init = packet_net_init,
2108         .exit = packet_net_exit,
2109 };
2110
2111
2112 static void __exit packet_exit(void)
2113 {
2114         unregister_netdevice_notifier(&packet_netdev_notifier);
2115         unregister_pernet_subsys(&packet_net_ops);
2116         sock_unregister(PF_PACKET);
2117         proto_unregister(&packet_proto);
2118 }
2119
2120 static int __init packet_init(void)
2121 {
2122         int rc = proto_register(&packet_proto, 0);
2123
2124         if (rc != 0)
2125                 goto out;
2126
2127         sock_register(&packet_family_ops);
2128         register_pernet_subsys(&packet_net_ops);
2129         register_netdevice_notifier(&packet_netdev_notifier);
2130 out:
2131         return rc;
2132 }
2133
2134 module_init(packet_init);
2135 module_exit(packet_exit);
2136 MODULE_LICENSE("GPL");
2137 MODULE_ALIAS_NETPROTO(PF_PACKET);