[AF_PACKET]: Allow for > 8 byte hardware addresses.
[linux-2.6.git] / net / packet / af_packet.c
1 /*
2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
3  *              operating system.  INET is implemented using the  BSD Socket
4  *              interface as the means of communication with the user level.
5  *
6  *              PACKET - implements raw packet sockets.
7  *
8  * Version:     $Id: af_packet.c,v 1.61 2002/02/08 03:57:19 davem Exp $
9  *
10  * Authors:     Ross Biro
11  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
13  *
14  * Fixes:       
15  *              Alan Cox        :       verify_area() now used correctly
16  *              Alan Cox        :       new skbuff lists, look ma no backlogs!
17  *              Alan Cox        :       tidied skbuff lists.
18  *              Alan Cox        :       Now uses generic datagram routines I
19  *                                      added. Also fixed the peek/read crash
20  *                                      from all old Linux datagram code.
21  *              Alan Cox        :       Uses the improved datagram code.
22  *              Alan Cox        :       Added NULL's for socket options.
23  *              Alan Cox        :       Re-commented the code.
24  *              Alan Cox        :       Use new kernel side addressing
25  *              Rob Janssen     :       Correct MTU usage.
26  *              Dave Platt      :       Counter leaks caused by incorrect
27  *                                      interrupt locking and some slightly
28  *                                      dubious gcc output. Can you read
29  *                                      compiler: it said _VOLATILE_
30  *      Richard Kooijman        :       Timestamp fixes.
31  *              Alan Cox        :       New buffers. Use sk->mac.raw.
32  *              Alan Cox        :       sendmsg/recvmsg support.
33  *              Alan Cox        :       Protocol setting support
34  *      Alexey Kuznetsov        :       Untied from IPv4 stack.
35  *      Cyrus Durgin            :       Fixed kerneld for kmod.
36  *      Michal Ostrowski        :       Module initialization cleanup.
37  *         Ulises Alonso        :       Frame number limit removal and 
38  *                                      packet_set_ring memory leak.
39  *              Eric Biederman  :       Allow for > 8 byte hardware addresses.
40  *                                      The convention is that longer addresses
41  *                                      will simply extend the hardware address
42  *                                      byte arrays at the end of sockaddr_ll 
43  *                                      and packet_mreq.
44  *
45  *              This program is free software; you can redistribute it and/or
46  *              modify it under the terms of the GNU General Public License
47  *              as published by the Free Software Foundation; either version
48  *              2 of the License, or (at your option) any later version.
49  *
50  */
51  
52 #include <linux/config.h>
53 #include <linux/types.h>
54 #include <linux/sched.h>
55 #include <linux/mm.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/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
81 #ifdef CONFIG_INET
82 #include <net/inet_common.h>
83 #endif
84
85 #define CONFIG_SOCK_PACKET      1
86
87 /*
88    Proposed replacement for SIOC{ADD,DEL}MULTI and
89    IFF_PROMISC, IFF_ALLMULTI flags.
90
91    It is more expensive, but I believe,
92    it is really correct solution: reentereble, safe and fault tolerant.
93
94    IFF_PROMISC/IFF_ALLMULTI/SIOC{ADD/DEL}MULTI are faked by keeping
95    reference count and global flag, so that real status is
96    (gflag|(count != 0)), so that we can use obsolete faulty interface
97    not harming clever users.
98  */
99 #define CONFIG_PACKET_MULTICAST 1
100
101 /*
102    Assumptions:
103    - if device has no dev->hard_header routine, it adds and removes ll header
104      inside itself. In this case ll header is invisible outside of device,
105      but higher levels still should reserve dev->hard_header_len.
106      Some devices are enough clever to reallocate skb, when header
107      will not fit to reserved space (tunnel), another ones are silly
108      (PPP).
109    - packet socket receives packets with pulled ll header,
110      so that SOCK_RAW should push it back.
111
112 On receive:
113 -----------
114
115 Incoming, dev->hard_header!=NULL
116    mac.raw -> ll header
117    data    -> data
118
119 Outgoing, dev->hard_header!=NULL
120    mac.raw -> ll header
121    data    -> ll header
122
123 Incoming, dev->hard_header==NULL
124    mac.raw -> UNKNOWN position. It is very likely, that it points to ll header.
125               PPP makes it, that is wrong, because introduce assymetry
126               between rx and tx paths.
127    data    -> data
128
129 Outgoing, dev->hard_header==NULL
130    mac.raw -> data. ll header is still not built!
131    data    -> data
132
133 Resume
134   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
135
136
137 On transmit:
138 ------------
139
140 dev->hard_header != NULL
141    mac.raw -> ll header
142    data    -> ll header
143
144 dev->hard_header == NULL (ll header is added by device, we cannot control it)
145    mac.raw -> data
146    data -> data
147
148    We should set nh.raw on output to correct posistion,
149    packet classifier depends on it.
150  */
151
152 /* List of all packet sockets. */
153 static HLIST_HEAD(packet_sklist);
154 static DEFINE_RWLOCK(packet_sklist_lock);
155
156 static atomic_t packet_socks_nr;
157
158
159 /* Private packet socket structures. */
160
161 #ifdef CONFIG_PACKET_MULTICAST
162 struct packet_mclist
163 {
164         struct packet_mclist    *next;
165         int                     ifindex;
166         int                     count;
167         unsigned short          type;
168         unsigned short          alen;
169         unsigned char           addr[MAX_ADDR_LEN];
170 };
171 /* identical to struct packet_mreq except it has
172  * a longer address field.
173  */
174 struct packet_mreq_max
175 {
176         int             mr_ifindex;
177         unsigned short  mr_type;
178         unsigned short  mr_alen;
179         unsigned char   mr_address[MAX_ADDR_LEN];
180 };
181 #endif
182 #ifdef CONFIG_PACKET_MMAP
183 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
184 #endif
185
186 static void packet_flush_mclist(struct sock *sk);
187
188 struct packet_sock {
189         /* struct sock has to be the first member of packet_sock */
190         struct sock             sk;
191         struct tpacket_stats    stats;
192 #ifdef CONFIG_PACKET_MMAP
193         char *                  *pg_vec;
194         unsigned int            head;
195         unsigned int            frames_per_block;
196         unsigned int            frame_size;
197         unsigned int            frame_max;
198         int                     copy_thresh;
199 #endif
200         struct packet_type      prot_hook;
201         spinlock_t              bind_lock;
202         char                    running;        /* prot_hook is attached*/
203         int                     ifindex;        /* bound device         */
204         unsigned short          num;
205 #ifdef CONFIG_PACKET_MULTICAST
206         struct packet_mclist    *mclist;
207 #endif
208 #ifdef CONFIG_PACKET_MMAP
209         atomic_t                mapped;
210         unsigned int            pg_vec_order;
211         unsigned int            pg_vec_pages;
212         unsigned int            pg_vec_len;
213 #endif
214 };
215
216 #ifdef CONFIG_PACKET_MMAP
217
218 static inline char *packet_lookup_frame(struct packet_sock *po, unsigned int position)
219 {
220         unsigned int pg_vec_pos, frame_offset;
221         char *frame;
222
223         pg_vec_pos = position / po->frames_per_block;
224         frame_offset = position % po->frames_per_block;
225
226         frame = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
227         
228         return frame;
229 }
230 #endif
231
232 static inline struct packet_sock *pkt_sk(struct sock *sk)
233 {
234         return (struct packet_sock *)sk;
235 }
236
237 static void packet_sock_destruct(struct sock *sk)
238 {
239         BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
240         BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
241
242         if (!sock_flag(sk, SOCK_DEAD)) {
243                 printk("Attempt to release alive packet socket: %p\n", sk);
244                 return;
245         }
246
247         atomic_dec(&packet_socks_nr);
248 #ifdef PACKET_REFCNT_DEBUG
249         printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
250 #endif
251 }
252
253
254 static struct proto_ops packet_ops;
255
256 #ifdef CONFIG_SOCK_PACKET
257 static struct proto_ops packet_ops_spkt;
258
259 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt, struct net_device *orig_dev)
260 {
261         struct sock *sk;
262         struct sockaddr_pkt *spkt;
263
264         /*
265          *      When we registered the protocol we saved the socket in the data
266          *      field for just this event.
267          */
268
269         sk = pt->af_packet_priv;
270         
271         /*
272          *      Yank back the headers [hope the device set this
273          *      right or kerboom...]
274          *
275          *      Incoming packets have ll header pulled,
276          *      push it back.
277          *
278          *      For outgoing ones skb->data == skb->mac.raw
279          *      so that this procedure is noop.
280          */
281
282         if (skb->pkt_type == PACKET_LOOPBACK)
283                 goto out;
284
285         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
286                 goto oom;
287
288         /* drop any routing info */
289         dst_release(skb->dst);
290         skb->dst = NULL;
291
292         /* drop conntrack reference */
293         nf_reset(skb);
294
295         spkt = (struct sockaddr_pkt*)skb->cb;
296
297         skb_push(skb, skb->data-skb->mac.raw);
298
299         /*
300          *      The SOCK_PACKET socket receives _all_ frames.
301          */
302
303         spkt->spkt_family = dev->type;
304         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
305         spkt->spkt_protocol = skb->protocol;
306
307         /*
308          *      Charge the memory to the socket. This is done specifically
309          *      to prevent sockets using all the memory up.
310          */
311
312         if (sock_queue_rcv_skb(sk,skb) == 0)
313                 return 0;
314
315 out:
316         kfree_skb(skb);
317 oom:
318         return 0;
319 }
320
321
322 /*
323  *      Output a raw packet to a device layer. This bypasses all the other
324  *      protocol layers and you must therefore supply it with a complete frame
325  */
326  
327 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
328                                struct msghdr *msg, size_t len)
329 {
330         struct sock *sk = sock->sk;
331         struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
332         struct sk_buff *skb;
333         struct net_device *dev;
334         unsigned short proto=0;
335         int err;
336         
337         /*
338          *      Get and verify the address. 
339          */
340
341         if (saddr)
342         {
343                 if (msg->msg_namelen < sizeof(struct sockaddr))
344                         return(-EINVAL);
345                 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
346                         proto=saddr->spkt_protocol;
347         }
348         else
349                 return(-ENOTCONN);      /* SOCK_PACKET must be sent giving an address */
350
351         /*
352          *      Find the device first to size check it 
353          */
354
355         saddr->spkt_device[13] = 0;
356         dev = dev_get_by_name(saddr->spkt_device);
357         err = -ENODEV;
358         if (dev == NULL)
359                 goto out_unlock;
360         
361         /*
362          *      You may not queue a frame bigger than the mtu. This is the lowest level
363          *      raw protocol and you must do your own fragmentation at this level.
364          */
365          
366         err = -EMSGSIZE;
367         if(len>dev->mtu+dev->hard_header_len)
368                 goto out_unlock;
369
370         err = -ENOBUFS;
371         skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
372
373         /*
374          *      If the write buffer is full, then tough. At this level the user gets to
375          *      deal with the problem - do your own algorithmic backoffs. That's far
376          *      more flexible.
377          */
378          
379         if (skb == NULL) 
380                 goto out_unlock;
381
382         /*
383          *      Fill it in 
384          */
385          
386         /* FIXME: Save some space for broken drivers that write a
387          * hard header at transmission time by themselves. PPP is the
388          * notable one here. This should really be fixed at the driver level.
389          */
390         skb_reserve(skb, LL_RESERVED_SPACE(dev));
391         skb->nh.raw = skb->data;
392
393         /* Try to align data part correctly */
394         if (dev->hard_header) {
395                 skb->data -= dev->hard_header_len;
396                 skb->tail -= dev->hard_header_len;
397                 if (len < dev->hard_header_len)
398                         skb->nh.raw = skb->data;
399         }
400
401         /* Returns -EFAULT on error */
402         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
403         skb->protocol = proto;
404         skb->dev = dev;
405         skb->priority = sk->sk_priority;
406         if (err)
407                 goto out_free;
408
409         err = -ENETDOWN;
410         if (!(dev->flags & IFF_UP))
411                 goto out_free;
412
413         /*
414          *      Now send it
415          */
416
417         dev_queue_xmit(skb);
418         dev_put(dev);
419         return(len);
420
421 out_free:
422         kfree_skb(skb);
423 out_unlock:
424         if (dev)
425                 dev_put(dev);
426         return err;
427 }
428 #endif
429
430 static inline unsigned run_filter(struct sk_buff *skb, struct sock *sk, unsigned res)
431 {
432         struct sk_filter *filter;
433
434         bh_lock_sock(sk);
435         filter = sk->sk_filter;
436         /*
437          * Our caller already checked that filter != NULL but we need to
438          * verify that under bh_lock_sock() to be safe
439          */
440         if (likely(filter != NULL))
441                 res = sk_run_filter(skb, filter->insns, filter->len);
442         bh_unlock_sock(sk);
443
444         return res;
445 }
446
447 /*
448    This function makes lazy skb cloning in hope that most of packets
449    are discarded by BPF.
450
451    Note tricky part: we DO mangle shared skb! skb->data, skb->len
452    and skb->cb are mangled. It works because (and until) packets
453    falling here are owned by current CPU. Output packets are cloned
454    by dev_queue_xmit_nit(), input packets are processed by net_bh
455    sequencially, so that if we return skb to original state on exit,
456    we will not harm anyone.
457  */
458
459 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
460 {
461         struct sock *sk;
462         struct sockaddr_ll *sll;
463         struct packet_sock *po;
464         u8 * skb_head = skb->data;
465         int skb_len = skb->len;
466         unsigned snaplen;
467
468         if (skb->pkt_type == PACKET_LOOPBACK)
469                 goto drop;
470
471         sk = pt->af_packet_priv;
472         po = pkt_sk(sk);
473
474         skb->dev = dev;
475
476         if (dev->hard_header) {
477                 /* The device has an explicit notion of ll header,
478                    exported to higher levels.
479
480                    Otherwise, the device hides datails of it frame
481                    structure, so that corresponding packet head
482                    never delivered to user.
483                  */
484                 if (sk->sk_type != SOCK_DGRAM)
485                         skb_push(skb, skb->data - skb->mac.raw);
486                 else if (skb->pkt_type == PACKET_OUTGOING) {
487                         /* Special case: outgoing packets have ll header at head */
488                         skb_pull(skb, skb->nh.raw - skb->data);
489                 }
490         }
491
492         snaplen = skb->len;
493
494         if (sk->sk_filter) {
495                 unsigned res = run_filter(skb, sk, snaplen);
496                 if (res == 0)
497                         goto drop_n_restore;
498                 if (snaplen > res)
499                         snaplen = res;
500         }
501
502         if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
503             (unsigned)sk->sk_rcvbuf)
504                 goto drop_n_acct;
505
506         if (skb_shared(skb)) {
507                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
508                 if (nskb == NULL)
509                         goto drop_n_acct;
510
511                 if (skb_head != skb->data) {
512                         skb->data = skb_head;
513                         skb->len = skb_len;
514                 }
515                 kfree_skb(skb);
516                 skb = nskb;
517         }
518
519         sll = (struct sockaddr_ll*)skb->cb;
520         sll->sll_family = AF_PACKET;
521         sll->sll_hatype = dev->type;
522         sll->sll_protocol = skb->protocol;
523         sll->sll_pkttype = skb->pkt_type;
524         sll->sll_ifindex = dev->ifindex;
525         sll->sll_halen = 0;
526
527         if (dev->hard_header_parse)
528                 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
529
530         if (pskb_trim(skb, snaplen))
531                 goto drop_n_acct;
532
533         skb_set_owner_r(skb, sk);
534         skb->dev = NULL;
535         dst_release(skb->dst);
536         skb->dst = NULL;
537
538         /* drop conntrack reference */
539         nf_reset(skb);
540
541         spin_lock(&sk->sk_receive_queue.lock);
542         po->stats.tp_packets++;
543         __skb_queue_tail(&sk->sk_receive_queue, skb);
544         spin_unlock(&sk->sk_receive_queue.lock);
545         sk->sk_data_ready(sk, skb->len);
546         return 0;
547
548 drop_n_acct:
549         spin_lock(&sk->sk_receive_queue.lock);
550         po->stats.tp_drops++;
551         spin_unlock(&sk->sk_receive_queue.lock);
552
553 drop_n_restore:
554         if (skb_head != skb->data && skb_shared(skb)) {
555                 skb->data = skb_head;
556                 skb->len = skb_len;
557         }
558 drop:
559         kfree_skb(skb);
560         return 0;
561 }
562
563 #ifdef CONFIG_PACKET_MMAP
564 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
565 {
566         struct sock *sk;
567         struct packet_sock *po;
568         struct sockaddr_ll *sll;
569         struct tpacket_hdr *h;
570         u8 * skb_head = skb->data;
571         int skb_len = skb->len;
572         unsigned snaplen;
573         unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
574         unsigned short macoff, netoff;
575         struct sk_buff *copy_skb = NULL;
576
577         if (skb->pkt_type == PACKET_LOOPBACK)
578                 goto drop;
579
580         sk = pt->af_packet_priv;
581         po = pkt_sk(sk);
582
583         if (dev->hard_header) {
584                 if (sk->sk_type != SOCK_DGRAM)
585                         skb_push(skb, skb->data - skb->mac.raw);
586                 else if (skb->pkt_type == PACKET_OUTGOING) {
587                         /* Special case: outgoing packets have ll header at head */
588                         skb_pull(skb, skb->nh.raw - skb->data);
589                         if (skb->ip_summed == CHECKSUM_HW)
590                                 status |= TP_STATUS_CSUMNOTREADY;
591                 }
592         }
593
594         snaplen = skb->len;
595
596         if (sk->sk_filter) {
597                 unsigned res = run_filter(skb, sk, snaplen);
598                 if (res == 0)
599                         goto drop_n_restore;
600                 if (snaplen > res)
601                         snaplen = res;
602         }
603
604         if (sk->sk_type == SOCK_DGRAM) {
605                 macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
606         } else {
607                 unsigned maclen = skb->nh.raw - skb->data;
608                 netoff = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
609                 macoff = netoff - maclen;
610         }
611
612         if (macoff + snaplen > po->frame_size) {
613                 if (po->copy_thresh &&
614                     atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
615                     (unsigned)sk->sk_rcvbuf) {
616                         if (skb_shared(skb)) {
617                                 copy_skb = skb_clone(skb, GFP_ATOMIC);
618                         } else {
619                                 copy_skb = skb_get(skb);
620                                 skb_head = skb->data;
621                         }
622                         if (copy_skb)
623                                 skb_set_owner_r(copy_skb, sk);
624                 }
625                 snaplen = po->frame_size - macoff;
626                 if ((int)snaplen < 0)
627                         snaplen = 0;
628         }
629         if (snaplen > skb->len-skb->data_len)
630                 snaplen = skb->len-skb->data_len;
631
632         spin_lock(&sk->sk_receive_queue.lock);
633         h = (struct tpacket_hdr *)packet_lookup_frame(po, po->head);
634         
635         if (h->tp_status)
636                 goto ring_is_full;
637         po->head = po->head != po->frame_max ? po->head+1 : 0;
638         po->stats.tp_packets++;
639         if (copy_skb) {
640                 status |= TP_STATUS_COPY;
641                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
642         }
643         if (!po->stats.tp_drops)
644                 status &= ~TP_STATUS_LOSING;
645         spin_unlock(&sk->sk_receive_queue.lock);
646
647         memcpy((u8*)h + macoff, skb->data, snaplen);
648
649         h->tp_len = skb->len;
650         h->tp_snaplen = snaplen;
651         h->tp_mac = macoff;
652         h->tp_net = netoff;
653         if (skb->tstamp.off_sec == 0) { 
654                 __net_timestamp(skb);
655                 sock_enable_timestamp(sk);
656         }
657         h->tp_sec = skb_tv_base.tv_sec + skb->tstamp.off_sec;
658         h->tp_usec = skb_tv_base.tv_usec + skb->tstamp.off_usec;
659
660         sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
661         sll->sll_halen = 0;
662         if (dev->hard_header_parse)
663                 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
664         sll->sll_family = AF_PACKET;
665         sll->sll_hatype = dev->type;
666         sll->sll_protocol = skb->protocol;
667         sll->sll_pkttype = skb->pkt_type;
668         sll->sll_ifindex = dev->ifindex;
669
670         h->tp_status = status;
671         mb();
672
673         {
674                 struct page *p_start, *p_end;
675                 u8 *h_end = (u8 *)h + macoff + snaplen - 1;
676
677                 p_start = virt_to_page(h);
678                 p_end = virt_to_page(h_end);
679                 while (p_start <= p_end) {
680                         flush_dcache_page(p_start);
681                         p_start++;
682                 }
683         }
684
685         sk->sk_data_ready(sk, 0);
686
687 drop_n_restore:
688         if (skb_head != skb->data && skb_shared(skb)) {
689                 skb->data = skb_head;
690                 skb->len = skb_len;
691         }
692 drop:
693         kfree_skb(skb);
694         return 0;
695
696 ring_is_full:
697         po->stats.tp_drops++;
698         spin_unlock(&sk->sk_receive_queue.lock);
699
700         sk->sk_data_ready(sk, 0);
701         if (copy_skb)
702                 kfree_skb(copy_skb);
703         goto drop_n_restore;
704 }
705
706 #endif
707
708
709 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
710                           struct msghdr *msg, size_t len)
711 {
712         struct sock *sk = sock->sk;
713         struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
714         struct sk_buff *skb;
715         struct net_device *dev;
716         unsigned short proto;
717         unsigned char *addr;
718         int ifindex, err, reserve = 0;
719
720         /*
721          *      Get and verify the address. 
722          */
723          
724         if (saddr == NULL) {
725                 struct packet_sock *po = pkt_sk(sk);
726
727                 ifindex = po->ifindex;
728                 proto   = po->num;
729                 addr    = NULL;
730         } else {
731                 err = -EINVAL;
732                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
733                         goto out;
734                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
735                         goto out;
736                 ifindex = saddr->sll_ifindex;
737                 proto   = saddr->sll_protocol;
738                 addr    = saddr->sll_addr;
739         }
740
741
742         dev = dev_get_by_index(ifindex);
743         err = -ENXIO;
744         if (dev == NULL)
745                 goto out_unlock;
746         if (sock->type == SOCK_RAW)
747                 reserve = dev->hard_header_len;
748
749         err = -EMSGSIZE;
750         if (len > dev->mtu+reserve)
751                 goto out_unlock;
752
753         skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
754                                 msg->msg_flags & MSG_DONTWAIT, &err);
755         if (skb==NULL)
756                 goto out_unlock;
757
758         skb_reserve(skb, LL_RESERVED_SPACE(dev));
759         skb->nh.raw = skb->data;
760
761         if (dev->hard_header) {
762                 int res;
763                 err = -EINVAL;
764                 if (saddr) {
765                         if (saddr->sll_halen != dev->addr_len)
766                                 goto out_free;
767                         if (saddr->sll_hatype != dev->type)
768                                 goto out_free;
769                 }
770                 res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
771                 if (sock->type != SOCK_DGRAM) {
772                         skb->tail = skb->data;
773                         skb->len = 0;
774                 } else if (res < 0)
775                         goto out_free;
776         }
777
778         /* Returns -EFAULT on error */
779         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
780         if (err)
781                 goto out_free;
782
783         skb->protocol = proto;
784         skb->dev = dev;
785         skb->priority = sk->sk_priority;
786
787         err = -ENETDOWN;
788         if (!(dev->flags & IFF_UP))
789                 goto out_free;
790
791         /*
792          *      Now send it
793          */
794
795         err = dev_queue_xmit(skb);
796         if (err > 0 && (err = net_xmit_errno(err)) != 0)
797                 goto out_unlock;
798
799         dev_put(dev);
800
801         return(len);
802
803 out_free:
804         kfree_skb(skb);
805 out_unlock:
806         if (dev)
807                 dev_put(dev);
808 out:
809         return err;
810 }
811
812 /*
813  *      Close a PACKET socket. This is fairly simple. We immediately go
814  *      to 'closed' state and remove our protocol entry in the device list.
815  */
816
817 static int packet_release(struct socket *sock)
818 {
819         struct sock *sk = sock->sk;
820         struct packet_sock *po;
821
822         if (!sk)
823                 return 0;
824
825         po = pkt_sk(sk);
826
827         write_lock_bh(&packet_sklist_lock);
828         sk_del_node_init(sk);
829         write_unlock_bh(&packet_sklist_lock);
830
831         /*
832          *      Unhook packet receive handler.
833          */
834
835         if (po->running) {
836                 /*
837                  *      Remove the protocol hook
838                  */
839                 dev_remove_pack(&po->prot_hook);
840                 po->running = 0;
841                 po->num = 0;
842                 __sock_put(sk);
843         }
844
845 #ifdef CONFIG_PACKET_MULTICAST
846         packet_flush_mclist(sk);
847 #endif
848
849 #ifdef CONFIG_PACKET_MMAP
850         if (po->pg_vec) {
851                 struct tpacket_req req;
852                 memset(&req, 0, sizeof(req));
853                 packet_set_ring(sk, &req, 1);
854         }
855 #endif
856
857         /*
858          *      Now the socket is dead. No more input will appear.
859          */
860
861         sock_orphan(sk);
862         sock->sk = NULL;
863
864         /* Purge queues */
865
866         skb_queue_purge(&sk->sk_receive_queue);
867
868         sock_put(sk);
869         return 0;
870 }
871
872 /*
873  *      Attach a packet hook.
874  */
875
876 static int packet_do_bind(struct sock *sk, struct net_device *dev, int protocol)
877 {
878         struct packet_sock *po = pkt_sk(sk);
879         /*
880          *      Detach an existing hook if present.
881          */
882
883         lock_sock(sk);
884
885         spin_lock(&po->bind_lock);
886         if (po->running) {
887                 __sock_put(sk);
888                 po->running = 0;
889                 po->num = 0;
890                 spin_unlock(&po->bind_lock);
891                 dev_remove_pack(&po->prot_hook);
892                 spin_lock(&po->bind_lock);
893         }
894
895         po->num = protocol;
896         po->prot_hook.type = protocol;
897         po->prot_hook.dev = dev;
898
899         po->ifindex = dev ? dev->ifindex : 0;
900
901         if (protocol == 0)
902                 goto out_unlock;
903
904         if (dev) {
905                 if (dev->flags&IFF_UP) {
906                         dev_add_pack(&po->prot_hook);
907                         sock_hold(sk);
908                         po->running = 1;
909                 } else {
910                         sk->sk_err = ENETDOWN;
911                         if (!sock_flag(sk, SOCK_DEAD))
912                                 sk->sk_error_report(sk);
913                 }
914         } else {
915                 dev_add_pack(&po->prot_hook);
916                 sock_hold(sk);
917                 po->running = 1;
918         }
919
920 out_unlock:
921         spin_unlock(&po->bind_lock);
922         release_sock(sk);
923         return 0;
924 }
925
926 /*
927  *      Bind a packet socket to a device
928  */
929
930 #ifdef CONFIG_SOCK_PACKET
931
932 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
933 {
934         struct sock *sk=sock->sk;
935         char name[15];
936         struct net_device *dev;
937         int err = -ENODEV;
938         
939         /*
940          *      Check legality
941          */
942          
943         if(addr_len!=sizeof(struct sockaddr))
944                 return -EINVAL;
945         strlcpy(name,uaddr->sa_data,sizeof(name));
946
947         dev = dev_get_by_name(name);
948         if (dev) {
949                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
950                 dev_put(dev);
951         }
952         return err;
953 }
954 #endif
955
956 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
957 {
958         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
959         struct sock *sk=sock->sk;
960         struct net_device *dev = NULL;
961         int err;
962
963
964         /*
965          *      Check legality
966          */
967          
968         if (addr_len < sizeof(struct sockaddr_ll))
969                 return -EINVAL;
970         if (sll->sll_family != AF_PACKET)
971                 return -EINVAL;
972
973         if (sll->sll_ifindex) {
974                 err = -ENODEV;
975                 dev = dev_get_by_index(sll->sll_ifindex);
976                 if (dev == NULL)
977                         goto out;
978         }
979         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
980         if (dev)
981                 dev_put(dev);
982
983 out:
984         return err;
985 }
986
987 static struct proto packet_proto = {
988         .name     = "PACKET",
989         .owner    = THIS_MODULE,
990         .obj_size = sizeof(struct packet_sock),
991 };
992
993 /*
994  *      Create a packet of type SOCK_PACKET. 
995  */
996
997 static int packet_create(struct socket *sock, int protocol)
998 {
999         struct sock *sk;
1000         struct packet_sock *po;
1001         int err;
1002
1003         if (!capable(CAP_NET_RAW))
1004                 return -EPERM;
1005         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW
1006 #ifdef CONFIG_SOCK_PACKET
1007             && sock->type != SOCK_PACKET
1008 #endif
1009             )
1010                 return -ESOCKTNOSUPPORT;
1011
1012         sock->state = SS_UNCONNECTED;
1013
1014         err = -ENOBUFS;
1015         sk = sk_alloc(PF_PACKET, GFP_KERNEL, &packet_proto, 1);
1016         if (sk == NULL)
1017                 goto out;
1018
1019         sock->ops = &packet_ops;
1020 #ifdef CONFIG_SOCK_PACKET
1021         if (sock->type == SOCK_PACKET)
1022                 sock->ops = &packet_ops_spkt;
1023 #endif
1024         sock_init_data(sock, sk);
1025
1026         po = pkt_sk(sk);
1027         sk->sk_family = PF_PACKET;
1028         po->num = protocol;
1029
1030         sk->sk_destruct = packet_sock_destruct;
1031         atomic_inc(&packet_socks_nr);
1032
1033         /*
1034          *      Attach a protocol block
1035          */
1036
1037         spin_lock_init(&po->bind_lock);
1038         po->prot_hook.func = packet_rcv;
1039 #ifdef CONFIG_SOCK_PACKET
1040         if (sock->type == SOCK_PACKET)
1041                 po->prot_hook.func = packet_rcv_spkt;
1042 #endif
1043         po->prot_hook.af_packet_priv = sk;
1044
1045         if (protocol) {
1046                 po->prot_hook.type = protocol;
1047                 dev_add_pack(&po->prot_hook);
1048                 sock_hold(sk);
1049                 po->running = 1;
1050         }
1051
1052         write_lock_bh(&packet_sklist_lock);
1053         sk_add_node(sk, &packet_sklist);
1054         write_unlock_bh(&packet_sklist_lock);
1055         return(0);
1056 out:
1057         return err;
1058 }
1059
1060 /*
1061  *      Pull a packet from our receive queue and hand it to the user.
1062  *      If necessary we block.
1063  */
1064
1065 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1066                           struct msghdr *msg, size_t len, int flags)
1067 {
1068         struct sock *sk = sock->sk;
1069         struct sk_buff *skb;
1070         int copied, err;
1071         struct sockaddr_ll *sll;
1072
1073         err = -EINVAL;
1074         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1075                 goto out;
1076
1077 #if 0
1078         /* What error should we return now? EUNATTACH? */
1079         if (pkt_sk(sk)->ifindex < 0)
1080                 return -ENODEV;
1081 #endif
1082
1083         /*
1084          *      Call the generic datagram receiver. This handles all sorts
1085          *      of horrible races and re-entrancy so we can forget about it
1086          *      in the protocol layers.
1087          *
1088          *      Now it will return ENETDOWN, if device have just gone down,
1089          *      but then it will block.
1090          */
1091
1092         skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1093
1094         /*
1095          *      An error occurred so return it. Because skb_recv_datagram() 
1096          *      handles the blocking we don't see and worry about blocking
1097          *      retries.
1098          */
1099
1100         if(skb==NULL)
1101                 goto out;
1102
1103         /*
1104          *      If the address length field is there to be filled in, we fill
1105          *      it in now.
1106          */
1107
1108         sll = (struct sockaddr_ll*)skb->cb;
1109         if (sock->type == SOCK_PACKET)
1110                 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1111         else
1112                 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1113
1114         /*
1115          *      You lose any data beyond the buffer you gave. If it worries a
1116          *      user program they can ask the device for its MTU anyway.
1117          */
1118
1119         copied = skb->len;
1120         if (copied > len)
1121         {
1122                 copied=len;
1123                 msg->msg_flags|=MSG_TRUNC;
1124         }
1125
1126         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1127         if (err)
1128                 goto out_free;
1129
1130         sock_recv_timestamp(msg, sk, skb);
1131
1132         if (msg->msg_name)
1133                 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1134
1135         /*
1136          *      Free or return the buffer as appropriate. Again this
1137          *      hides all the races and re-entrancy issues from us.
1138          */
1139         err = (flags&MSG_TRUNC) ? skb->len : copied;
1140
1141 out_free:
1142         skb_free_datagram(sk, skb);
1143 out:
1144         return err;
1145 }
1146
1147 #ifdef CONFIG_SOCK_PACKET
1148 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1149                                int *uaddr_len, int peer)
1150 {
1151         struct net_device *dev;
1152         struct sock *sk = sock->sk;
1153
1154         if (peer)
1155                 return -EOPNOTSUPP;
1156
1157         uaddr->sa_family = AF_PACKET;
1158         dev = dev_get_by_index(pkt_sk(sk)->ifindex);
1159         if (dev) {
1160                 strlcpy(uaddr->sa_data, dev->name, 15);
1161                 dev_put(dev);
1162         } else
1163                 memset(uaddr->sa_data, 0, 14);
1164         *uaddr_len = sizeof(*uaddr);
1165
1166         return 0;
1167 }
1168 #endif
1169
1170 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1171                           int *uaddr_len, int peer)
1172 {
1173         struct net_device *dev;
1174         struct sock *sk = sock->sk;
1175         struct packet_sock *po = pkt_sk(sk);
1176         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1177
1178         if (peer)
1179                 return -EOPNOTSUPP;
1180
1181         sll->sll_family = AF_PACKET;
1182         sll->sll_ifindex = po->ifindex;
1183         sll->sll_protocol = po->num;
1184         dev = dev_get_by_index(po->ifindex);
1185         if (dev) {
1186                 sll->sll_hatype = dev->type;
1187                 sll->sll_halen = dev->addr_len;
1188                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1189                 dev_put(dev);
1190         } else {
1191                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
1192                 sll->sll_halen = 0;
1193         }
1194         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1195
1196         return 0;
1197 }
1198
1199 #ifdef CONFIG_PACKET_MULTICAST
1200 static void packet_dev_mc(struct net_device *dev, struct packet_mclist *i, int what)
1201 {
1202         switch (i->type) {
1203         case PACKET_MR_MULTICAST:
1204                 if (what > 0)
1205                         dev_mc_add(dev, i->addr, i->alen, 0);
1206                 else
1207                         dev_mc_delete(dev, i->addr, i->alen, 0);
1208                 break;
1209         case PACKET_MR_PROMISC:
1210                 dev_set_promiscuity(dev, what);
1211                 break;
1212         case PACKET_MR_ALLMULTI:
1213                 dev_set_allmulti(dev, what);
1214                 break;
1215         default:;
1216         }
1217 }
1218
1219 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1220 {
1221         for ( ; i; i=i->next) {
1222                 if (i->ifindex == dev->ifindex)
1223                         packet_dev_mc(dev, i, what);
1224         }
1225 }
1226
1227 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1228 {
1229         struct packet_sock *po = pkt_sk(sk);
1230         struct packet_mclist *ml, *i;
1231         struct net_device *dev;
1232         int err;
1233
1234         rtnl_lock();
1235
1236         err = -ENODEV;
1237         dev = __dev_get_by_index(mreq->mr_ifindex);
1238         if (!dev)
1239                 goto done;
1240
1241         err = -EINVAL;
1242         if (mreq->mr_alen > dev->addr_len)
1243                 goto done;
1244
1245         err = -ENOBUFS;
1246         i = (struct packet_mclist *)kmalloc(sizeof(*i), GFP_KERNEL);
1247         if (i == NULL)
1248                 goto done;
1249
1250         err = 0;
1251         for (ml = po->mclist; ml; ml = ml->next) {
1252                 if (ml->ifindex == mreq->mr_ifindex &&
1253                     ml->type == mreq->mr_type &&
1254                     ml->alen == mreq->mr_alen &&
1255                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1256                         ml->count++;
1257                         /* Free the new element ... */
1258                         kfree(i);
1259                         goto done;
1260                 }
1261         }
1262
1263         i->type = mreq->mr_type;
1264         i->ifindex = mreq->mr_ifindex;
1265         i->alen = mreq->mr_alen;
1266         memcpy(i->addr, mreq->mr_address, i->alen);
1267         i->count = 1;
1268         i->next = po->mclist;
1269         po->mclist = i;
1270         packet_dev_mc(dev, i, +1);
1271
1272 done:
1273         rtnl_unlock();
1274         return err;
1275 }
1276
1277 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1278 {
1279         struct packet_mclist *ml, **mlp;
1280
1281         rtnl_lock();
1282
1283         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1284                 if (ml->ifindex == mreq->mr_ifindex &&
1285                     ml->type == mreq->mr_type &&
1286                     ml->alen == mreq->mr_alen &&
1287                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1288                         if (--ml->count == 0) {
1289                                 struct net_device *dev;
1290                                 *mlp = ml->next;
1291                                 dev = dev_get_by_index(ml->ifindex);
1292                                 if (dev) {
1293                                         packet_dev_mc(dev, ml, -1);
1294                                         dev_put(dev);
1295                                 }
1296                                 kfree(ml);
1297                         }
1298                         rtnl_unlock();
1299                         return 0;
1300                 }
1301         }
1302         rtnl_unlock();
1303         return -EADDRNOTAVAIL;
1304 }
1305
1306 static void packet_flush_mclist(struct sock *sk)
1307 {
1308         struct packet_sock *po = pkt_sk(sk);
1309         struct packet_mclist *ml;
1310
1311         if (!po->mclist)
1312                 return;
1313
1314         rtnl_lock();
1315         while ((ml = po->mclist) != NULL) {
1316                 struct net_device *dev;
1317
1318                 po->mclist = ml->next;
1319                 if ((dev = dev_get_by_index(ml->ifindex)) != NULL) {
1320                         packet_dev_mc(dev, ml, -1);
1321                         dev_put(dev);
1322                 }
1323                 kfree(ml);
1324         }
1325         rtnl_unlock();
1326 }
1327 #endif
1328
1329 static int
1330 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1331 {
1332         struct sock *sk = sock->sk;
1333         int ret;
1334
1335         if (level != SOL_PACKET)
1336                 return -ENOPROTOOPT;
1337
1338         switch(optname) {
1339 #ifdef CONFIG_PACKET_MULTICAST
1340         case PACKET_ADD_MEMBERSHIP:     
1341         case PACKET_DROP_MEMBERSHIP:
1342         {
1343                 struct packet_mreq_max mreq;
1344                 int len = optlen;
1345                 memset(&mreq, 0, sizeof(mreq));
1346                 if (len < sizeof(struct packet_mreq))
1347                         return -EINVAL;
1348                 if (len > sizeof(mreq))
1349                         len = sizeof(mreq);
1350                 if (copy_from_user(&mreq,optval,len))
1351                         return -EFAULT;
1352                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1353                         return -EINVAL;
1354                 if (optname == PACKET_ADD_MEMBERSHIP)
1355                         ret = packet_mc_add(sk, &mreq);
1356                 else
1357                         ret = packet_mc_drop(sk, &mreq);
1358                 return ret;
1359         }
1360 #endif
1361 #ifdef CONFIG_PACKET_MMAP
1362         case PACKET_RX_RING:
1363         {
1364                 struct tpacket_req req;
1365
1366                 if (optlen<sizeof(req))
1367                         return -EINVAL;
1368                 if (copy_from_user(&req,optval,sizeof(req)))
1369                         return -EFAULT;
1370                 return packet_set_ring(sk, &req, 0);
1371         }
1372         case PACKET_COPY_THRESH:
1373         {
1374                 int val;
1375
1376                 if (optlen!=sizeof(val))
1377                         return -EINVAL;
1378                 if (copy_from_user(&val,optval,sizeof(val)))
1379                         return -EFAULT;
1380
1381                 pkt_sk(sk)->copy_thresh = val;
1382                 return 0;
1383         }
1384 #endif
1385         default:
1386                 return -ENOPROTOOPT;
1387         }
1388 }
1389
1390 static int packet_getsockopt(struct socket *sock, int level, int optname,
1391                              char __user *optval, int __user *optlen)
1392 {
1393         int len;
1394         struct sock *sk = sock->sk;
1395         struct packet_sock *po = pkt_sk(sk);
1396
1397         if (level != SOL_PACKET)
1398                 return -ENOPROTOOPT;
1399
1400         if (get_user(len,optlen))
1401                 return -EFAULT;
1402
1403         if (len < 0)
1404                 return -EINVAL;
1405                 
1406         switch(optname) {
1407         case PACKET_STATISTICS:
1408         {
1409                 struct tpacket_stats st;
1410
1411                 if (len > sizeof(struct tpacket_stats))
1412                         len = sizeof(struct tpacket_stats);
1413                 spin_lock_bh(&sk->sk_receive_queue.lock);
1414                 st = po->stats;
1415                 memset(&po->stats, 0, sizeof(st));
1416                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1417                 st.tp_packets += st.tp_drops;
1418
1419                 if (copy_to_user(optval, &st, len))
1420                         return -EFAULT;
1421                 break;
1422         }
1423         default:
1424                 return -ENOPROTOOPT;
1425         }
1426
1427         if (put_user(len, optlen))
1428                 return -EFAULT;
1429         return 0;
1430 }
1431
1432
1433 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1434 {
1435         struct sock *sk;
1436         struct hlist_node *node;
1437         struct net_device *dev = (struct net_device*)data;
1438
1439         read_lock(&packet_sklist_lock);
1440         sk_for_each(sk, node, &packet_sklist) {
1441                 struct packet_sock *po = pkt_sk(sk);
1442
1443                 switch (msg) {
1444                 case NETDEV_UNREGISTER:
1445 #ifdef CONFIG_PACKET_MULTICAST
1446                         if (po->mclist)
1447                                 packet_dev_mclist(dev, po->mclist, -1);
1448                         // fallthrough
1449 #endif
1450                 case NETDEV_DOWN:
1451                         if (dev->ifindex == po->ifindex) {
1452                                 spin_lock(&po->bind_lock);
1453                                 if (po->running) {
1454                                         __dev_remove_pack(&po->prot_hook);
1455                                         __sock_put(sk);
1456                                         po->running = 0;
1457                                         sk->sk_err = ENETDOWN;
1458                                         if (!sock_flag(sk, SOCK_DEAD))
1459                                                 sk->sk_error_report(sk);
1460                                 }
1461                                 if (msg == NETDEV_UNREGISTER) {
1462                                         po->ifindex = -1;
1463                                         po->prot_hook.dev = NULL;
1464                                 }
1465                                 spin_unlock(&po->bind_lock);
1466                         }
1467                         break;
1468                 case NETDEV_UP:
1469                         spin_lock(&po->bind_lock);
1470                         if (dev->ifindex == po->ifindex && po->num &&
1471                             !po->running) {
1472                                 dev_add_pack(&po->prot_hook);
1473                                 sock_hold(sk);
1474                                 po->running = 1;
1475                         }
1476                         spin_unlock(&po->bind_lock);
1477                         break;
1478                 }
1479         }
1480         read_unlock(&packet_sklist_lock);
1481         return NOTIFY_DONE;
1482 }
1483
1484
1485 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1486                         unsigned long arg)
1487 {
1488         struct sock *sk = sock->sk;
1489
1490         switch(cmd) {
1491                 case SIOCOUTQ:
1492                 {
1493                         int amount = atomic_read(&sk->sk_wmem_alloc);
1494                         return put_user(amount, (int __user *)arg);
1495                 }
1496                 case SIOCINQ:
1497                 {
1498                         struct sk_buff *skb;
1499                         int amount = 0;
1500
1501                         spin_lock_bh(&sk->sk_receive_queue.lock);
1502                         skb = skb_peek(&sk->sk_receive_queue);
1503                         if (skb)
1504                                 amount = skb->len;
1505                         spin_unlock_bh(&sk->sk_receive_queue.lock);
1506                         return put_user(amount, (int __user *)arg);
1507                 }
1508                 case SIOCGSTAMP:
1509                         return sock_get_timestamp(sk, (struct timeval __user *)arg);
1510                         
1511 #ifdef CONFIG_INET
1512                 case SIOCADDRT:
1513                 case SIOCDELRT:
1514                 case SIOCDARP:
1515                 case SIOCGARP:
1516                 case SIOCSARP:
1517                 case SIOCGIFADDR:
1518                 case SIOCSIFADDR:
1519                 case SIOCGIFBRDADDR:
1520                 case SIOCSIFBRDADDR:
1521                 case SIOCGIFNETMASK:
1522                 case SIOCSIFNETMASK:
1523                 case SIOCGIFDSTADDR:
1524                 case SIOCSIFDSTADDR:
1525                 case SIOCSIFFLAGS:
1526                         return inet_dgram_ops.ioctl(sock, cmd, arg);
1527 #endif
1528
1529                 default:
1530                         return dev_ioctl(cmd, (void __user *)arg);
1531         }
1532         return 0;
1533 }
1534
1535 #ifndef CONFIG_PACKET_MMAP
1536 #define packet_mmap sock_no_mmap
1537 #define packet_poll datagram_poll
1538 #else
1539
1540 static unsigned int packet_poll(struct file * file, struct socket *sock,
1541                                 poll_table *wait)
1542 {
1543         struct sock *sk = sock->sk;
1544         struct packet_sock *po = pkt_sk(sk);
1545         unsigned int mask = datagram_poll(file, sock, wait);
1546
1547         spin_lock_bh(&sk->sk_receive_queue.lock);
1548         if (po->pg_vec) {
1549                 unsigned last = po->head ? po->head-1 : po->frame_max;
1550                 struct tpacket_hdr *h;
1551
1552                 h = (struct tpacket_hdr *)packet_lookup_frame(po, last);
1553
1554                 if (h->tp_status)
1555                         mask |= POLLIN | POLLRDNORM;
1556         }
1557         spin_unlock_bh(&sk->sk_receive_queue.lock);
1558         return mask;
1559 }
1560
1561
1562 /* Dirty? Well, I still did not learn better way to account
1563  * for user mmaps.
1564  */
1565
1566 static void packet_mm_open(struct vm_area_struct *vma)
1567 {
1568         struct file *file = vma->vm_file;
1569         struct socket * sock = file->private_data;
1570         struct sock *sk = sock->sk;
1571         
1572         if (sk)
1573                 atomic_inc(&pkt_sk(sk)->mapped);
1574 }
1575
1576 static void packet_mm_close(struct vm_area_struct *vma)
1577 {
1578         struct file *file = vma->vm_file;
1579         struct socket * sock = file->private_data;
1580         struct sock *sk = sock->sk;
1581         
1582         if (sk)
1583                 atomic_dec(&pkt_sk(sk)->mapped);
1584 }
1585
1586 static struct vm_operations_struct packet_mmap_ops = {
1587         .open = packet_mm_open,
1588         .close =packet_mm_close,
1589 };
1590
1591 static inline struct page *pg_vec_endpage(char *one_pg_vec, unsigned int order)
1592 {
1593         return virt_to_page(one_pg_vec + (PAGE_SIZE << order) - 1);
1594 }
1595
1596 static void free_pg_vec(char **pg_vec, unsigned order, unsigned len)
1597 {
1598         int i;
1599
1600         for (i=0; i<len; i++) {
1601                 if (pg_vec[i]) {
1602                         struct page *page, *pend;
1603
1604                         pend = pg_vec_endpage(pg_vec[i], order);
1605                         for (page = virt_to_page(pg_vec[i]); page <= pend; page++)
1606                                 ClearPageReserved(page);
1607                         free_pages((unsigned long)pg_vec[i], order);
1608                 }
1609         }
1610         kfree(pg_vec);
1611 }
1612
1613
1614 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1615 {
1616         char **pg_vec = NULL;
1617         struct packet_sock *po = pkt_sk(sk);
1618         int was_running, num, order = 0;
1619         int err = 0;
1620         
1621         if (req->tp_block_nr) {
1622                 int i, l;
1623
1624                 /* Sanity tests and some calculations */
1625
1626                 if (po->pg_vec)
1627                         return -EBUSY;
1628
1629                 if ((int)req->tp_block_size <= 0)
1630                         return -EINVAL;
1631                 if (req->tp_block_size&(PAGE_SIZE-1))
1632                         return -EINVAL;
1633                 if (req->tp_frame_size < TPACKET_HDRLEN)
1634                         return -EINVAL;
1635                 if (req->tp_frame_size&(TPACKET_ALIGNMENT-1))
1636                         return -EINVAL;
1637
1638                 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1639                 if (po->frames_per_block <= 0)
1640                         return -EINVAL;
1641                 if (po->frames_per_block*req->tp_block_nr != req->tp_frame_nr)
1642                         return -EINVAL;
1643                 /* OK! */
1644
1645                 /* Allocate page vector */
1646                 while ((PAGE_SIZE<<order) < req->tp_block_size)
1647                         order++;
1648
1649                 err = -ENOMEM;
1650
1651                 pg_vec = kmalloc(req->tp_block_nr*sizeof(char *), GFP_KERNEL);
1652                 if (pg_vec == NULL)
1653                         goto out;
1654                 memset(pg_vec, 0, req->tp_block_nr*sizeof(char **));
1655
1656                 for (i=0; i<req->tp_block_nr; i++) {
1657                         struct page *page, *pend;
1658                         pg_vec[i] = (char *)__get_free_pages(GFP_KERNEL, order);
1659                         if (!pg_vec[i])
1660                                 goto out_free_pgvec;
1661
1662                         pend = pg_vec_endpage(pg_vec[i], order);
1663                         for (page = virt_to_page(pg_vec[i]); page <= pend; page++)
1664                                 SetPageReserved(page);
1665                 }
1666                 /* Page vector is allocated */
1667
1668                 l = 0;
1669                 for (i=0; i<req->tp_block_nr; i++) {
1670                         char *ptr = pg_vec[i];
1671                         struct tpacket_hdr *header;
1672                         int k;
1673
1674                         for (k=0; k<po->frames_per_block; k++) {
1675                                 
1676                                 header = (struct tpacket_hdr*)ptr;
1677                                 header->tp_status = TP_STATUS_KERNEL;
1678                                 ptr += req->tp_frame_size;
1679                         }
1680                 }
1681                 /* Done */
1682         } else {
1683                 if (req->tp_frame_nr)
1684                         return -EINVAL;
1685         }
1686
1687         lock_sock(sk);
1688
1689         /* Detach socket from network */
1690         spin_lock(&po->bind_lock);
1691         was_running = po->running;
1692         num = po->num;
1693         if (was_running) {
1694                 __dev_remove_pack(&po->prot_hook);
1695                 po->num = 0;
1696                 po->running = 0;
1697                 __sock_put(sk);
1698         }
1699         spin_unlock(&po->bind_lock);
1700                 
1701         synchronize_net();
1702
1703         err = -EBUSY;
1704         if (closing || atomic_read(&po->mapped) == 0) {
1705                 err = 0;
1706 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1707
1708                 spin_lock_bh(&sk->sk_receive_queue.lock);
1709                 pg_vec = XC(po->pg_vec, pg_vec);
1710                 po->frame_max = req->tp_frame_nr-1;
1711                 po->head = 0;
1712                 po->frame_size = req->tp_frame_size;
1713                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1714
1715                 order = XC(po->pg_vec_order, order);
1716                 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1717
1718                 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1719                 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1720                 skb_queue_purge(&sk->sk_receive_queue);
1721 #undef XC
1722                 if (atomic_read(&po->mapped))
1723                         printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1724         }
1725
1726         spin_lock(&po->bind_lock);
1727         if (was_running && !po->running) {
1728                 sock_hold(sk);
1729                 po->running = 1;
1730                 po->num = num;
1731                 dev_add_pack(&po->prot_hook);
1732         }
1733         spin_unlock(&po->bind_lock);
1734
1735         release_sock(sk);
1736
1737 out_free_pgvec:
1738         if (pg_vec)
1739                 free_pg_vec(pg_vec, order, req->tp_block_nr);
1740 out:
1741         return err;
1742 }
1743
1744 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1745 {
1746         struct sock *sk = sock->sk;
1747         struct packet_sock *po = pkt_sk(sk);
1748         unsigned long size;
1749         unsigned long start;
1750         int err = -EINVAL;
1751         int i;
1752
1753         if (vma->vm_pgoff)
1754                 return -EINVAL;
1755
1756         size = vma->vm_end - vma->vm_start;
1757
1758         lock_sock(sk);
1759         if (po->pg_vec == NULL)
1760                 goto out;
1761         if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1762                 goto out;
1763
1764         atomic_inc(&po->mapped);
1765         start = vma->vm_start;
1766         err = -EAGAIN;
1767         for (i=0; i<po->pg_vec_len; i++) {
1768                 if (remap_pfn_range(vma, start,
1769                                      __pa(po->pg_vec[i]) >> PAGE_SHIFT,
1770                                      po->pg_vec_pages*PAGE_SIZE,
1771                                      vma->vm_page_prot))
1772                         goto out;
1773                 start += po->pg_vec_pages*PAGE_SIZE;
1774         }
1775         vma->vm_ops = &packet_mmap_ops;
1776         err = 0;
1777
1778 out:
1779         release_sock(sk);
1780         return err;
1781 }
1782 #endif
1783
1784
1785 #ifdef CONFIG_SOCK_PACKET
1786 static struct proto_ops packet_ops_spkt = {
1787         .family =       PF_PACKET,
1788         .owner =        THIS_MODULE,
1789         .release =      packet_release,
1790         .bind =         packet_bind_spkt,
1791         .connect =      sock_no_connect,
1792         .socketpair =   sock_no_socketpair,
1793         .accept =       sock_no_accept,
1794         .getname =      packet_getname_spkt,
1795         .poll =         datagram_poll,
1796         .ioctl =        packet_ioctl,
1797         .listen =       sock_no_listen,
1798         .shutdown =     sock_no_shutdown,
1799         .setsockopt =   sock_no_setsockopt,
1800         .getsockopt =   sock_no_getsockopt,
1801         .sendmsg =      packet_sendmsg_spkt,
1802         .recvmsg =      packet_recvmsg,
1803         .mmap =         sock_no_mmap,
1804         .sendpage =     sock_no_sendpage,
1805 };
1806 #endif
1807
1808 static struct proto_ops packet_ops = {
1809         .family =       PF_PACKET,
1810         .owner =        THIS_MODULE,
1811         .release =      packet_release,
1812         .bind =         packet_bind,
1813         .connect =      sock_no_connect,
1814         .socketpair =   sock_no_socketpair,
1815         .accept =       sock_no_accept,
1816         .getname =      packet_getname, 
1817         .poll =         packet_poll,
1818         .ioctl =        packet_ioctl,
1819         .listen =       sock_no_listen,
1820         .shutdown =     sock_no_shutdown,
1821         .setsockopt =   packet_setsockopt,
1822         .getsockopt =   packet_getsockopt,
1823         .sendmsg =      packet_sendmsg,
1824         .recvmsg =      packet_recvmsg,
1825         .mmap =         packet_mmap,
1826         .sendpage =     sock_no_sendpage,
1827 };
1828
1829 static struct net_proto_family packet_family_ops = {
1830         .family =       PF_PACKET,
1831         .create =       packet_create,
1832         .owner  =       THIS_MODULE,
1833 };
1834
1835 static struct notifier_block packet_netdev_notifier = {
1836         .notifier_call =packet_notifier,
1837 };
1838
1839 #ifdef CONFIG_PROC_FS
1840 static inline struct sock *packet_seq_idx(loff_t off)
1841 {
1842         struct sock *s;
1843         struct hlist_node *node;
1844
1845         sk_for_each(s, node, &packet_sklist) {
1846                 if (!off--)
1847                         return s;
1848         }
1849         return NULL;
1850 }
1851
1852 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
1853 {
1854         read_lock(&packet_sklist_lock);
1855         return *pos ? packet_seq_idx(*pos - 1) : SEQ_START_TOKEN;
1856 }
1857
1858 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1859 {
1860         ++*pos;
1861         return  (v == SEQ_START_TOKEN) 
1862                 ? sk_head(&packet_sklist) 
1863                 : sk_next((struct sock*)v) ;
1864 }
1865
1866 static void packet_seq_stop(struct seq_file *seq, void *v)
1867 {
1868         read_unlock(&packet_sklist_lock);               
1869 }
1870
1871 static int packet_seq_show(struct seq_file *seq, void *v) 
1872 {
1873         if (v == SEQ_START_TOKEN)
1874                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
1875         else {
1876                 struct sock *s = v;
1877                 const struct packet_sock *po = pkt_sk(s);
1878
1879                 seq_printf(seq,
1880                            "%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
1881                            s,
1882                            atomic_read(&s->sk_refcnt),
1883                            s->sk_type,
1884                            ntohs(po->num),
1885                            po->ifindex,
1886                            po->running,
1887                            atomic_read(&s->sk_rmem_alloc),
1888                            sock_i_uid(s),
1889                            sock_i_ino(s) );
1890         }
1891
1892         return 0;
1893 }
1894
1895 static struct seq_operations packet_seq_ops = {
1896         .start  = packet_seq_start,
1897         .next   = packet_seq_next,
1898         .stop   = packet_seq_stop,
1899         .show   = packet_seq_show,
1900 };
1901
1902 static int packet_seq_open(struct inode *inode, struct file *file)
1903 {
1904         return seq_open(file, &packet_seq_ops);
1905 }
1906
1907 static struct file_operations packet_seq_fops = {
1908         .owner          = THIS_MODULE,
1909         .open           = packet_seq_open,
1910         .read           = seq_read,
1911         .llseek         = seq_lseek,
1912         .release        = seq_release,
1913 };
1914
1915 #endif
1916
1917 static void __exit packet_exit(void)
1918 {
1919         proc_net_remove("packet");
1920         unregister_netdevice_notifier(&packet_netdev_notifier);
1921         sock_unregister(PF_PACKET);
1922         proto_unregister(&packet_proto);
1923 }
1924
1925 static int __init packet_init(void)
1926 {
1927         int rc = proto_register(&packet_proto, 0);
1928
1929         if (rc != 0)
1930                 goto out;
1931
1932         sock_register(&packet_family_ops);
1933         register_netdevice_notifier(&packet_netdev_notifier);
1934         proc_net_fops_create("packet", 0, &packet_seq_fops);
1935 out:
1936         return rc;
1937 }
1938
1939 module_init(packet_init);
1940 module_exit(packet_exit);
1941 MODULE_LICENSE("GPL");
1942 MODULE_ALIAS_NETPROTO(PF_PACKET);