]> Pileus Git - ~andy/linux/blob - net/packet/af_packet.c
packet: fix a couple of cppcheck warnings
[~andy/linux] / 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  *              Johann Baudy    :       Added TX RING.
43  *              Chetan Loke     :       Implemented TPACKET_V3 block abstraction
44  *                                      layer.
45  *                                      Copyright (C) 2011, <lokec@ccs.neu.edu>
46  *
47  *
48  *              This program is free software; you can redistribute it and/or
49  *              modify it under the terms of the GNU General Public License
50  *              as published by the Free Software Foundation; either version
51  *              2 of the License, or (at your option) any later version.
52  *
53  */
54
55 #include <linux/types.h>
56 #include <linux/mm.h>
57 #include <linux/capability.h>
58 #include <linux/fcntl.h>
59 #include <linux/socket.h>
60 #include <linux/in.h>
61 #include <linux/inet.h>
62 #include <linux/netdevice.h>
63 #include <linux/if_packet.h>
64 #include <linux/wireless.h>
65 #include <linux/kernel.h>
66 #include <linux/kmod.h>
67 #include <linux/slab.h>
68 #include <linux/vmalloc.h>
69 #include <net/net_namespace.h>
70 #include <net/ip.h>
71 #include <net/protocol.h>
72 #include <linux/skbuff.h>
73 #include <net/sock.h>
74 #include <linux/errno.h>
75 #include <linux/timer.h>
76 #include <asm/uaccess.h>
77 #include <asm/ioctls.h>
78 #include <asm/page.h>
79 #include <asm/cacheflush.h>
80 #include <asm/io.h>
81 #include <linux/proc_fs.h>
82 #include <linux/seq_file.h>
83 #include <linux/poll.h>
84 #include <linux/module.h>
85 #include <linux/init.h>
86 #include <linux/mutex.h>
87 #include <linux/if_vlan.h>
88 #include <linux/virtio_net.h>
89 #include <linux/errqueue.h>
90 #include <linux/net_tstamp.h>
91 #include <linux/reciprocal_div.h>
92 #include <linux/percpu.h>
93 #ifdef CONFIG_INET
94 #include <net/inet_common.h>
95 #endif
96
97 #include "internal.h"
98
99 /*
100    Assumptions:
101    - if device has no dev->hard_header routine, it adds and removes ll header
102      inside itself. In this case ll header is invisible outside of device,
103      but higher levels still should reserve dev->hard_header_len.
104      Some devices are enough clever to reallocate skb, when header
105      will not fit to reserved space (tunnel), another ones are silly
106      (PPP).
107    - packet socket receives packets with pulled ll header,
108      so that SOCK_RAW should push it back.
109
110 On receive:
111 -----------
112
113 Incoming, dev->hard_header!=NULL
114    mac_header -> ll header
115    data       -> data
116
117 Outgoing, dev->hard_header!=NULL
118    mac_header -> ll header
119    data       -> ll header
120
121 Incoming, dev->hard_header==NULL
122    mac_header -> UNKNOWN position. It is very likely, that it points to ll
123                  header.  PPP makes it, that is wrong, because introduce
124                  assymetry between rx and tx paths.
125    data       -> data
126
127 Outgoing, dev->hard_header==NULL
128    mac_header -> data. ll header is still not built!
129    data       -> data
130
131 Resume
132   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
133
134
135 On transmit:
136 ------------
137
138 dev->hard_header != NULL
139    mac_header -> ll header
140    data       -> ll header
141
142 dev->hard_header == NULL (ll header is added by device, we cannot control it)
143    mac_header -> data
144    data       -> data
145
146    We should set nh.raw on output to correct posistion,
147    packet classifier depends on it.
148  */
149
150 /* Private packet socket structures. */
151
152 /* identical to struct packet_mreq except it has
153  * a longer address field.
154  */
155 struct packet_mreq_max {
156         int             mr_ifindex;
157         unsigned short  mr_type;
158         unsigned short  mr_alen;
159         unsigned char   mr_address[MAX_ADDR_LEN];
160 };
161
162 union tpacket_uhdr {
163         struct tpacket_hdr  *h1;
164         struct tpacket2_hdr *h2;
165         struct tpacket3_hdr *h3;
166         void *raw;
167 };
168
169 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
170                 int closing, int tx_ring);
171
172 #define V3_ALIGNMENT    (8)
173
174 #define BLK_HDR_LEN     (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
175
176 #define BLK_PLUS_PRIV(sz_of_priv) \
177         (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
178
179 #define PGV_FROM_VMALLOC 1
180
181 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
182 #define BLOCK_NUM_PKTS(x)       ((x)->hdr.bh1.num_pkts)
183 #define BLOCK_O2FP(x)           ((x)->hdr.bh1.offset_to_first_pkt)
184 #define BLOCK_LEN(x)            ((x)->hdr.bh1.blk_len)
185 #define BLOCK_SNUM(x)           ((x)->hdr.bh1.seq_num)
186 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
187 #define BLOCK_PRIV(x)           ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
188
189 struct packet_sock;
190 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
191 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
192                        struct packet_type *pt, struct net_device *orig_dev);
193
194 static void *packet_previous_frame(struct packet_sock *po,
195                 struct packet_ring_buffer *rb,
196                 int status);
197 static void packet_increment_head(struct packet_ring_buffer *buff);
198 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
199                         struct tpacket_block_desc *);
200 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
201                         struct packet_sock *);
202 static void prb_retire_current_block(struct tpacket_kbdq_core *,
203                 struct packet_sock *, unsigned int status);
204 static int prb_queue_frozen(struct tpacket_kbdq_core *);
205 static void prb_open_block(struct tpacket_kbdq_core *,
206                 struct tpacket_block_desc *);
207 static void prb_retire_rx_blk_timer_expired(unsigned long);
208 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
209 static void prb_init_blk_timer(struct packet_sock *,
210                 struct tpacket_kbdq_core *,
211                 void (*func) (unsigned long));
212 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
213 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
214                 struct tpacket3_hdr *);
215 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
216                 struct tpacket3_hdr *);
217 static void packet_flush_mclist(struct sock *sk);
218
219 struct packet_skb_cb {
220         unsigned int origlen;
221         union {
222                 struct sockaddr_pkt pkt;
223                 struct sockaddr_ll ll;
224         } sa;
225 };
226
227 #define PACKET_SKB_CB(__skb)    ((struct packet_skb_cb *)((__skb)->cb))
228
229 #define GET_PBDQC_FROM_RB(x)    ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
230 #define GET_PBLOCK_DESC(x, bid) \
231         ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
232 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x)       \
233         ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
234 #define GET_NEXT_PRB_BLK_NUM(x) \
235         (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
236         ((x)->kactive_blk_num+1) : 0)
237
238 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
239 static void __fanout_link(struct sock *sk, struct packet_sock *po);
240
241 static int packet_direct_xmit(struct sk_buff *skb)
242 {
243         struct net_device *dev = skb->dev;
244         const struct net_device_ops *ops = dev->netdev_ops;
245         netdev_features_t features;
246         struct netdev_queue *txq;
247         u16 queue_map;
248         int ret;
249
250         if (unlikely(!netif_running(dev) ||
251                      !netif_carrier_ok(dev))) {
252                 kfree_skb(skb);
253                 return NET_XMIT_DROP;
254         }
255
256         features = netif_skb_features(skb);
257         if (skb_needs_linearize(skb, features) &&
258             __skb_linearize(skb)) {
259                 kfree_skb(skb);
260                 return NET_XMIT_DROP;
261         }
262
263         queue_map = skb_get_queue_mapping(skb);
264         txq = netdev_get_tx_queue(dev, queue_map);
265
266         __netif_tx_lock_bh(txq);
267         if (unlikely(netif_xmit_frozen_or_stopped(txq))) {
268                 ret = NETDEV_TX_BUSY;
269                 kfree_skb(skb);
270                 goto out;
271         }
272
273         ret = ops->ndo_start_xmit(skb, dev);
274         if (likely(dev_xmit_complete(ret)))
275                 txq_trans_update(txq);
276         else
277                 kfree_skb(skb);
278 out:
279         __netif_tx_unlock_bh(txq);
280         return ret;
281 }
282
283 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
284 {
285         struct net_device *dev;
286
287         rcu_read_lock();
288         dev = rcu_dereference(po->cached_dev);
289         if (likely(dev))
290                 dev_hold(dev);
291         rcu_read_unlock();
292
293         return dev;
294 }
295
296 static void packet_cached_dev_assign(struct packet_sock *po,
297                                      struct net_device *dev)
298 {
299         rcu_assign_pointer(po->cached_dev, dev);
300 }
301
302 static void packet_cached_dev_reset(struct packet_sock *po)
303 {
304         RCU_INIT_POINTER(po->cached_dev, NULL);
305 }
306
307 static bool packet_use_direct_xmit(const struct packet_sock *po)
308 {
309         return po->xmit == packet_direct_xmit;
310 }
311
312 static u16 packet_pick_tx_queue(struct net_device *dev)
313 {
314         return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
315 }
316
317 /* register_prot_hook must be invoked with the po->bind_lock held,
318  * or from a context in which asynchronous accesses to the packet
319  * socket is not possible (packet_create()).
320  */
321 static void register_prot_hook(struct sock *sk)
322 {
323         struct packet_sock *po = pkt_sk(sk);
324
325         if (!po->running) {
326                 if (po->fanout)
327                         __fanout_link(sk, po);
328                 else
329                         dev_add_pack(&po->prot_hook);
330
331                 sock_hold(sk);
332                 po->running = 1;
333         }
334 }
335
336 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
337  * held.   If the sync parameter is true, we will temporarily drop
338  * the po->bind_lock and do a synchronize_net to make sure no
339  * asynchronous packet processing paths still refer to the elements
340  * of po->prot_hook.  If the sync parameter is false, it is the
341  * callers responsibility to take care of this.
342  */
343 static void __unregister_prot_hook(struct sock *sk, bool sync)
344 {
345         struct packet_sock *po = pkt_sk(sk);
346
347         po->running = 0;
348
349         if (po->fanout)
350                 __fanout_unlink(sk, po);
351         else
352                 __dev_remove_pack(&po->prot_hook);
353
354         __sock_put(sk);
355
356         if (sync) {
357                 spin_unlock(&po->bind_lock);
358                 synchronize_net();
359                 spin_lock(&po->bind_lock);
360         }
361 }
362
363 static void unregister_prot_hook(struct sock *sk, bool sync)
364 {
365         struct packet_sock *po = pkt_sk(sk);
366
367         if (po->running)
368                 __unregister_prot_hook(sk, sync);
369 }
370
371 static inline __pure struct page *pgv_to_page(void *addr)
372 {
373         if (is_vmalloc_addr(addr))
374                 return vmalloc_to_page(addr);
375         return virt_to_page(addr);
376 }
377
378 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
379 {
380         union tpacket_uhdr h;
381
382         h.raw = frame;
383         switch (po->tp_version) {
384         case TPACKET_V1:
385                 h.h1->tp_status = status;
386                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
387                 break;
388         case TPACKET_V2:
389                 h.h2->tp_status = status;
390                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
391                 break;
392         case TPACKET_V3:
393         default:
394                 WARN(1, "TPACKET version not supported.\n");
395                 BUG();
396         }
397
398         smp_wmb();
399 }
400
401 static int __packet_get_status(struct packet_sock *po, void *frame)
402 {
403         union tpacket_uhdr h;
404
405         smp_rmb();
406
407         h.raw = frame;
408         switch (po->tp_version) {
409         case TPACKET_V1:
410                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
411                 return h.h1->tp_status;
412         case TPACKET_V2:
413                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
414                 return h.h2->tp_status;
415         case TPACKET_V3:
416         default:
417                 WARN(1, "TPACKET version not supported.\n");
418                 BUG();
419                 return 0;
420         }
421 }
422
423 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
424                                    unsigned int flags)
425 {
426         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
427
428         if (shhwtstamps) {
429                 if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
430                     ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
431                         return TP_STATUS_TS_SYS_HARDWARE;
432                 if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
433                     ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
434                         return TP_STATUS_TS_RAW_HARDWARE;
435         }
436
437         if (ktime_to_timespec_cond(skb->tstamp, ts))
438                 return TP_STATUS_TS_SOFTWARE;
439
440         return 0;
441 }
442
443 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
444                                     struct sk_buff *skb)
445 {
446         union tpacket_uhdr h;
447         struct timespec ts;
448         __u32 ts_status;
449
450         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
451                 return 0;
452
453         h.raw = frame;
454         switch (po->tp_version) {
455         case TPACKET_V1:
456                 h.h1->tp_sec = ts.tv_sec;
457                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
458                 break;
459         case TPACKET_V2:
460                 h.h2->tp_sec = ts.tv_sec;
461                 h.h2->tp_nsec = ts.tv_nsec;
462                 break;
463         case TPACKET_V3:
464         default:
465                 WARN(1, "TPACKET version not supported.\n");
466                 BUG();
467         }
468
469         /* one flush is safe, as both fields always lie on the same cacheline */
470         flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
471         smp_wmb();
472
473         return ts_status;
474 }
475
476 static void *packet_lookup_frame(struct packet_sock *po,
477                 struct packet_ring_buffer *rb,
478                 unsigned int position,
479                 int status)
480 {
481         unsigned int pg_vec_pos, frame_offset;
482         union tpacket_uhdr h;
483
484         pg_vec_pos = position / rb->frames_per_block;
485         frame_offset = position % rb->frames_per_block;
486
487         h.raw = rb->pg_vec[pg_vec_pos].buffer +
488                 (frame_offset * rb->frame_size);
489
490         if (status != __packet_get_status(po, h.raw))
491                 return NULL;
492
493         return h.raw;
494 }
495
496 static void *packet_current_frame(struct packet_sock *po,
497                 struct packet_ring_buffer *rb,
498                 int status)
499 {
500         return packet_lookup_frame(po, rb, rb->head, status);
501 }
502
503 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
504 {
505         del_timer_sync(&pkc->retire_blk_timer);
506 }
507
508 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
509                 int tx_ring,
510                 struct sk_buff_head *rb_queue)
511 {
512         struct tpacket_kbdq_core *pkc;
513
514         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
515                         GET_PBDQC_FROM_RB(&po->rx_ring);
516
517         spin_lock_bh(&rb_queue->lock);
518         pkc->delete_blk_timer = 1;
519         spin_unlock_bh(&rb_queue->lock);
520
521         prb_del_retire_blk_timer(pkc);
522 }
523
524 static void prb_init_blk_timer(struct packet_sock *po,
525                 struct tpacket_kbdq_core *pkc,
526                 void (*func) (unsigned long))
527 {
528         init_timer(&pkc->retire_blk_timer);
529         pkc->retire_blk_timer.data = (long)po;
530         pkc->retire_blk_timer.function = func;
531         pkc->retire_blk_timer.expires = jiffies;
532 }
533
534 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
535 {
536         struct tpacket_kbdq_core *pkc;
537
538         if (tx_ring)
539                 BUG();
540
541         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
542                         GET_PBDQC_FROM_RB(&po->rx_ring);
543         prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
544 }
545
546 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
547                                 int blk_size_in_bytes)
548 {
549         struct net_device *dev;
550         unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
551         struct ethtool_cmd ecmd;
552         int err;
553         u32 speed;
554
555         rtnl_lock();
556         dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
557         if (unlikely(!dev)) {
558                 rtnl_unlock();
559                 return DEFAULT_PRB_RETIRE_TOV;
560         }
561         err = __ethtool_get_settings(dev, &ecmd);
562         speed = ethtool_cmd_speed(&ecmd);
563         rtnl_unlock();
564         if (!err) {
565                 /*
566                  * If the link speed is so slow you don't really
567                  * need to worry about perf anyways
568                  */
569                 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
570                         return DEFAULT_PRB_RETIRE_TOV;
571                 } else {
572                         msec = 1;
573                         div = speed / 1000;
574                 }
575         }
576
577         mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
578
579         if (div)
580                 mbits /= div;
581
582         tmo = mbits * msec;
583
584         if (div)
585                 return tmo+1;
586         return tmo;
587 }
588
589 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
590                         union tpacket_req_u *req_u)
591 {
592         p1->feature_req_word = req_u->req3.tp_feature_req_word;
593 }
594
595 static void init_prb_bdqc(struct packet_sock *po,
596                         struct packet_ring_buffer *rb,
597                         struct pgv *pg_vec,
598                         union tpacket_req_u *req_u, int tx_ring)
599 {
600         struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
601         struct tpacket_block_desc *pbd;
602
603         memset(p1, 0x0, sizeof(*p1));
604
605         p1->knxt_seq_num = 1;
606         p1->pkbdq = pg_vec;
607         pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
608         p1->pkblk_start = pg_vec[0].buffer;
609         p1->kblk_size = req_u->req3.tp_block_size;
610         p1->knum_blocks = req_u->req3.tp_block_nr;
611         p1->hdrlen = po->tp_hdrlen;
612         p1->version = po->tp_version;
613         p1->last_kactive_blk_num = 0;
614         po->stats.stats3.tp_freeze_q_cnt = 0;
615         if (req_u->req3.tp_retire_blk_tov)
616                 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
617         else
618                 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
619                                                 req_u->req3.tp_block_size);
620         p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
621         p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
622
623         prb_init_ft_ops(p1, req_u);
624         prb_setup_retire_blk_timer(po, tx_ring);
625         prb_open_block(p1, pbd);
626 }
627
628 /*  Do NOT update the last_blk_num first.
629  *  Assumes sk_buff_head lock is held.
630  */
631 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
632 {
633         mod_timer(&pkc->retire_blk_timer,
634                         jiffies + pkc->tov_in_jiffies);
635         pkc->last_kactive_blk_num = pkc->kactive_blk_num;
636 }
637
638 /*
639  * Timer logic:
640  * 1) We refresh the timer only when we open a block.
641  *    By doing this we don't waste cycles refreshing the timer
642  *        on packet-by-packet basis.
643  *
644  * With a 1MB block-size, on a 1Gbps line, it will take
645  * i) ~8 ms to fill a block + ii) memcpy etc.
646  * In this cut we are not accounting for the memcpy time.
647  *
648  * So, if the user sets the 'tmo' to 10ms then the timer
649  * will never fire while the block is still getting filled
650  * (which is what we want). However, the user could choose
651  * to close a block early and that's fine.
652  *
653  * But when the timer does fire, we check whether or not to refresh it.
654  * Since the tmo granularity is in msecs, it is not too expensive
655  * to refresh the timer, lets say every '8' msecs.
656  * Either the user can set the 'tmo' or we can derive it based on
657  * a) line-speed and b) block-size.
658  * prb_calc_retire_blk_tmo() calculates the tmo.
659  *
660  */
661 static void prb_retire_rx_blk_timer_expired(unsigned long data)
662 {
663         struct packet_sock *po = (struct packet_sock *)data;
664         struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
665         unsigned int frozen;
666         struct tpacket_block_desc *pbd;
667
668         spin_lock(&po->sk.sk_receive_queue.lock);
669
670         frozen = prb_queue_frozen(pkc);
671         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
672
673         if (unlikely(pkc->delete_blk_timer))
674                 goto out;
675
676         /* We only need to plug the race when the block is partially filled.
677          * tpacket_rcv:
678          *              lock(); increment BLOCK_NUM_PKTS; unlock()
679          *              copy_bits() is in progress ...
680          *              timer fires on other cpu:
681          *              we can't retire the current block because copy_bits
682          *              is in progress.
683          *
684          */
685         if (BLOCK_NUM_PKTS(pbd)) {
686                 while (atomic_read(&pkc->blk_fill_in_prog)) {
687                         /* Waiting for skb_copy_bits to finish... */
688                         cpu_relax();
689                 }
690         }
691
692         if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
693                 if (!frozen) {
694                         prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
695                         if (!prb_dispatch_next_block(pkc, po))
696                                 goto refresh_timer;
697                         else
698                                 goto out;
699                 } else {
700                         /* Case 1. Queue was frozen because user-space was
701                          *         lagging behind.
702                          */
703                         if (prb_curr_blk_in_use(pkc, pbd)) {
704                                 /*
705                                  * Ok, user-space is still behind.
706                                  * So just refresh the timer.
707                                  */
708                                 goto refresh_timer;
709                         } else {
710                                /* Case 2. queue was frozen,user-space caught up,
711                                 * now the link went idle && the timer fired.
712                                 * We don't have a block to close.So we open this
713                                 * block and restart the timer.
714                                 * opening a block thaws the queue,restarts timer
715                                 * Thawing/timer-refresh is a side effect.
716                                 */
717                                 prb_open_block(pkc, pbd);
718                                 goto out;
719                         }
720                 }
721         }
722
723 refresh_timer:
724         _prb_refresh_rx_retire_blk_timer(pkc);
725
726 out:
727         spin_unlock(&po->sk.sk_receive_queue.lock);
728 }
729
730 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
731                 struct tpacket_block_desc *pbd1, __u32 status)
732 {
733         /* Flush everything minus the block header */
734
735 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
736         u8 *start, *end;
737
738         start = (u8 *)pbd1;
739
740         /* Skip the block header(we know header WILL fit in 4K) */
741         start += PAGE_SIZE;
742
743         end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
744         for (; start < end; start += PAGE_SIZE)
745                 flush_dcache_page(pgv_to_page(start));
746
747         smp_wmb();
748 #endif
749
750         /* Now update the block status. */
751
752         BLOCK_STATUS(pbd1) = status;
753
754         /* Flush the block header */
755
756 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
757         start = (u8 *)pbd1;
758         flush_dcache_page(pgv_to_page(start));
759
760         smp_wmb();
761 #endif
762 }
763
764 /*
765  * Side effect:
766  *
767  * 1) flush the block
768  * 2) Increment active_blk_num
769  *
770  * Note:We DONT refresh the timer on purpose.
771  *      Because almost always the next block will be opened.
772  */
773 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
774                 struct tpacket_block_desc *pbd1,
775                 struct packet_sock *po, unsigned int stat)
776 {
777         __u32 status = TP_STATUS_USER | stat;
778
779         struct tpacket3_hdr *last_pkt;
780         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
781
782         if (po->stats.stats3.tp_drops)
783                 status |= TP_STATUS_LOSING;
784
785         last_pkt = (struct tpacket3_hdr *)pkc1->prev;
786         last_pkt->tp_next_offset = 0;
787
788         /* Get the ts of the last pkt */
789         if (BLOCK_NUM_PKTS(pbd1)) {
790                 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
791                 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
792         } else {
793                 /* Ok, we tmo'd - so get the current time */
794                 struct timespec ts;
795                 getnstimeofday(&ts);
796                 h1->ts_last_pkt.ts_sec = ts.tv_sec;
797                 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
798         }
799
800         smp_wmb();
801
802         /* Flush the block */
803         prb_flush_block(pkc1, pbd1, status);
804
805         pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
806 }
807
808 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
809 {
810         pkc->reset_pending_on_curr_blk = 0;
811 }
812
813 /*
814  * Side effect of opening a block:
815  *
816  * 1) prb_queue is thawed.
817  * 2) retire_blk_timer is refreshed.
818  *
819  */
820 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
821         struct tpacket_block_desc *pbd1)
822 {
823         struct timespec ts;
824         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
825
826         smp_rmb();
827
828         /* We could have just memset this but we will lose the
829          * flexibility of making the priv area sticky
830          */
831
832         BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
833         BLOCK_NUM_PKTS(pbd1) = 0;
834         BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
835
836         getnstimeofday(&ts);
837
838         h1->ts_first_pkt.ts_sec = ts.tv_sec;
839         h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
840
841         pkc1->pkblk_start = (char *)pbd1;
842         pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
843
844         BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
845         BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
846
847         pbd1->version = pkc1->version;
848         pkc1->prev = pkc1->nxt_offset;
849         pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
850
851         prb_thaw_queue(pkc1);
852         _prb_refresh_rx_retire_blk_timer(pkc1);
853
854         smp_wmb();
855 }
856
857 /*
858  * Queue freeze logic:
859  * 1) Assume tp_block_nr = 8 blocks.
860  * 2) At time 't0', user opens Rx ring.
861  * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
862  * 4) user-space is either sleeping or processing block '0'.
863  * 5) tpacket_rcv is currently filling block '7', since there is no space left,
864  *    it will close block-7,loop around and try to fill block '0'.
865  *    call-flow:
866  *    __packet_lookup_frame_in_block
867  *      prb_retire_current_block()
868  *      prb_dispatch_next_block()
869  *        |->(BLOCK_STATUS == USER) evaluates to true
870  *    5.1) Since block-0 is currently in-use, we just freeze the queue.
871  * 6) Now there are two cases:
872  *    6.1) Link goes idle right after the queue is frozen.
873  *         But remember, the last open_block() refreshed the timer.
874  *         When this timer expires,it will refresh itself so that we can
875  *         re-open block-0 in near future.
876  *    6.2) Link is busy and keeps on receiving packets. This is a simple
877  *         case and __packet_lookup_frame_in_block will check if block-0
878  *         is free and can now be re-used.
879  */
880 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
881                                   struct packet_sock *po)
882 {
883         pkc->reset_pending_on_curr_blk = 1;
884         po->stats.stats3.tp_freeze_q_cnt++;
885 }
886
887 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
888
889 /*
890  * If the next block is free then we will dispatch it
891  * and return a good offset.
892  * Else, we will freeze the queue.
893  * So, caller must check the return value.
894  */
895 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
896                 struct packet_sock *po)
897 {
898         struct tpacket_block_desc *pbd;
899
900         smp_rmb();
901
902         /* 1. Get current block num */
903         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
904
905         /* 2. If this block is currently in_use then freeze the queue */
906         if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
907                 prb_freeze_queue(pkc, po);
908                 return NULL;
909         }
910
911         /*
912          * 3.
913          * open this block and return the offset where the first packet
914          * needs to get stored.
915          */
916         prb_open_block(pkc, pbd);
917         return (void *)pkc->nxt_offset;
918 }
919
920 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
921                 struct packet_sock *po, unsigned int status)
922 {
923         struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
924
925         /* retire/close the current block */
926         if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
927                 /*
928                  * Plug the case where copy_bits() is in progress on
929                  * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
930                  * have space to copy the pkt in the current block and
931                  * called prb_retire_current_block()
932                  *
933                  * We don't need to worry about the TMO case because
934                  * the timer-handler already handled this case.
935                  */
936                 if (!(status & TP_STATUS_BLK_TMO)) {
937                         while (atomic_read(&pkc->blk_fill_in_prog)) {
938                                 /* Waiting for skb_copy_bits to finish... */
939                                 cpu_relax();
940                         }
941                 }
942                 prb_close_block(pkc, pbd, po, status);
943                 return;
944         }
945 }
946
947 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
948                                       struct tpacket_block_desc *pbd)
949 {
950         return TP_STATUS_USER & BLOCK_STATUS(pbd);
951 }
952
953 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
954 {
955         return pkc->reset_pending_on_curr_blk;
956 }
957
958 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
959 {
960         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
961         atomic_dec(&pkc->blk_fill_in_prog);
962 }
963
964 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
965                         struct tpacket3_hdr *ppd)
966 {
967         ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
968 }
969
970 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
971                         struct tpacket3_hdr *ppd)
972 {
973         ppd->hv1.tp_rxhash = 0;
974 }
975
976 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
977                         struct tpacket3_hdr *ppd)
978 {
979         if (vlan_tx_tag_present(pkc->skb)) {
980                 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
981                 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
982                 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
983         } else {
984                 ppd->hv1.tp_vlan_tci = 0;
985                 ppd->hv1.tp_vlan_tpid = 0;
986                 ppd->tp_status = TP_STATUS_AVAILABLE;
987         }
988 }
989
990 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
991                         struct tpacket3_hdr *ppd)
992 {
993         ppd->hv1.tp_padding = 0;
994         prb_fill_vlan_info(pkc, ppd);
995
996         if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
997                 prb_fill_rxhash(pkc, ppd);
998         else
999                 prb_clear_rxhash(pkc, ppd);
1000 }
1001
1002 static void prb_fill_curr_block(char *curr,
1003                                 struct tpacket_kbdq_core *pkc,
1004                                 struct tpacket_block_desc *pbd,
1005                                 unsigned int len)
1006 {
1007         struct tpacket3_hdr *ppd;
1008
1009         ppd  = (struct tpacket3_hdr *)curr;
1010         ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1011         pkc->prev = curr;
1012         pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1013         BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1014         BLOCK_NUM_PKTS(pbd) += 1;
1015         atomic_inc(&pkc->blk_fill_in_prog);
1016         prb_run_all_ft_ops(pkc, ppd);
1017 }
1018
1019 /* Assumes caller has the sk->rx_queue.lock */
1020 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1021                                             struct sk_buff *skb,
1022                                                 int status,
1023                                             unsigned int len
1024                                             )
1025 {
1026         struct tpacket_kbdq_core *pkc;
1027         struct tpacket_block_desc *pbd;
1028         char *curr, *end;
1029
1030         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1031         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1032
1033         /* Queue is frozen when user space is lagging behind */
1034         if (prb_queue_frozen(pkc)) {
1035                 /*
1036                  * Check if that last block which caused the queue to freeze,
1037                  * is still in_use by user-space.
1038                  */
1039                 if (prb_curr_blk_in_use(pkc, pbd)) {
1040                         /* Can't record this packet */
1041                         return NULL;
1042                 } else {
1043                         /*
1044                          * Ok, the block was released by user-space.
1045                          * Now let's open that block.
1046                          * opening a block also thaws the queue.
1047                          * Thawing is a side effect.
1048                          */
1049                         prb_open_block(pkc, pbd);
1050                 }
1051         }
1052
1053         smp_mb();
1054         curr = pkc->nxt_offset;
1055         pkc->skb = skb;
1056         end = (char *)pbd + pkc->kblk_size;
1057
1058         /* first try the current block */
1059         if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1060                 prb_fill_curr_block(curr, pkc, pbd, len);
1061                 return (void *)curr;
1062         }
1063
1064         /* Ok, close the current block */
1065         prb_retire_current_block(pkc, po, 0);
1066
1067         /* Now, try to dispatch the next block */
1068         curr = (char *)prb_dispatch_next_block(pkc, po);
1069         if (curr) {
1070                 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1071                 prb_fill_curr_block(curr, pkc, pbd, len);
1072                 return (void *)curr;
1073         }
1074
1075         /*
1076          * No free blocks are available.user_space hasn't caught up yet.
1077          * Queue was just frozen and now this packet will get dropped.
1078          */
1079         return NULL;
1080 }
1081
1082 static void *packet_current_rx_frame(struct packet_sock *po,
1083                                             struct sk_buff *skb,
1084                                             int status, unsigned int len)
1085 {
1086         char *curr = NULL;
1087         switch (po->tp_version) {
1088         case TPACKET_V1:
1089         case TPACKET_V2:
1090                 curr = packet_lookup_frame(po, &po->rx_ring,
1091                                         po->rx_ring.head, status);
1092                 return curr;
1093         case TPACKET_V3:
1094                 return __packet_lookup_frame_in_block(po, skb, status, len);
1095         default:
1096                 WARN(1, "TPACKET version not supported\n");
1097                 BUG();
1098                 return NULL;
1099         }
1100 }
1101
1102 static void *prb_lookup_block(struct packet_sock *po,
1103                                      struct packet_ring_buffer *rb,
1104                                      unsigned int idx,
1105                                      int status)
1106 {
1107         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1108         struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1109
1110         if (status != BLOCK_STATUS(pbd))
1111                 return NULL;
1112         return pbd;
1113 }
1114
1115 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1116 {
1117         unsigned int prev;
1118         if (rb->prb_bdqc.kactive_blk_num)
1119                 prev = rb->prb_bdqc.kactive_blk_num-1;
1120         else
1121                 prev = rb->prb_bdqc.knum_blocks-1;
1122         return prev;
1123 }
1124
1125 /* Assumes caller has held the rx_queue.lock */
1126 static void *__prb_previous_block(struct packet_sock *po,
1127                                          struct packet_ring_buffer *rb,
1128                                          int status)
1129 {
1130         unsigned int previous = prb_previous_blk_num(rb);
1131         return prb_lookup_block(po, rb, previous, status);
1132 }
1133
1134 static void *packet_previous_rx_frame(struct packet_sock *po,
1135                                              struct packet_ring_buffer *rb,
1136                                              int status)
1137 {
1138         if (po->tp_version <= TPACKET_V2)
1139                 return packet_previous_frame(po, rb, status);
1140
1141         return __prb_previous_block(po, rb, status);
1142 }
1143
1144 static void packet_increment_rx_head(struct packet_sock *po,
1145                                             struct packet_ring_buffer *rb)
1146 {
1147         switch (po->tp_version) {
1148         case TPACKET_V1:
1149         case TPACKET_V2:
1150                 return packet_increment_head(rb);
1151         case TPACKET_V3:
1152         default:
1153                 WARN(1, "TPACKET version not supported.\n");
1154                 BUG();
1155                 return;
1156         }
1157 }
1158
1159 static void *packet_previous_frame(struct packet_sock *po,
1160                 struct packet_ring_buffer *rb,
1161                 int status)
1162 {
1163         unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1164         return packet_lookup_frame(po, rb, previous, status);
1165 }
1166
1167 static void packet_increment_head(struct packet_ring_buffer *buff)
1168 {
1169         buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1170 }
1171
1172 static void packet_inc_pending(struct packet_ring_buffer *rb)
1173 {
1174         this_cpu_inc(*rb->pending_refcnt);
1175 }
1176
1177 static void packet_dec_pending(struct packet_ring_buffer *rb)
1178 {
1179         this_cpu_dec(*rb->pending_refcnt);
1180 }
1181
1182 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1183 {
1184         unsigned int refcnt = 0;
1185         int cpu;
1186
1187         /* We don't use pending refcount in rx_ring. */
1188         if (rb->pending_refcnt == NULL)
1189                 return 0;
1190
1191         for_each_possible_cpu(cpu)
1192                 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1193
1194         return refcnt;
1195 }
1196
1197 static int packet_alloc_pending(struct packet_sock *po)
1198 {
1199         po->rx_ring.pending_refcnt = NULL;
1200
1201         po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1202         if (unlikely(po->tx_ring.pending_refcnt == NULL))
1203                 return -ENOBUFS;
1204
1205         return 0;
1206 }
1207
1208 static void packet_free_pending(struct packet_sock *po)
1209 {
1210         free_percpu(po->tx_ring.pending_refcnt);
1211 }
1212
1213 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1214 {
1215         struct sock *sk = &po->sk;
1216         bool has_room;
1217
1218         if (po->prot_hook.func != tpacket_rcv)
1219                 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1220                         <= sk->sk_rcvbuf;
1221
1222         spin_lock(&sk->sk_receive_queue.lock);
1223         if (po->tp_version == TPACKET_V3)
1224                 has_room = prb_lookup_block(po, &po->rx_ring,
1225                                             po->rx_ring.prb_bdqc.kactive_blk_num,
1226                                             TP_STATUS_KERNEL);
1227         else
1228                 has_room = packet_lookup_frame(po, &po->rx_ring,
1229                                                po->rx_ring.head,
1230                                                TP_STATUS_KERNEL);
1231         spin_unlock(&sk->sk_receive_queue.lock);
1232
1233         return has_room;
1234 }
1235
1236 static void packet_sock_destruct(struct sock *sk)
1237 {
1238         skb_queue_purge(&sk->sk_error_queue);
1239
1240         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1241         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1242
1243         if (!sock_flag(sk, SOCK_DEAD)) {
1244                 pr_err("Attempt to release alive packet socket: %p\n", sk);
1245                 return;
1246         }
1247
1248         sk_refcnt_debug_dec(sk);
1249 }
1250
1251 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1252 {
1253         int x = atomic_read(&f->rr_cur) + 1;
1254
1255         if (x >= num)
1256                 x = 0;
1257
1258         return x;
1259 }
1260
1261 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1262                                       struct sk_buff *skb,
1263                                       unsigned int num)
1264 {
1265         return reciprocal_divide(skb->rxhash, num);
1266 }
1267
1268 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1269                                     struct sk_buff *skb,
1270                                     unsigned int num)
1271 {
1272         int cur, old;
1273
1274         cur = atomic_read(&f->rr_cur);
1275         while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1276                                      fanout_rr_next(f, num))) != cur)
1277                 cur = old;
1278         return cur;
1279 }
1280
1281 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1282                                      struct sk_buff *skb,
1283                                      unsigned int num)
1284 {
1285         return smp_processor_id() % num;
1286 }
1287
1288 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1289                                      struct sk_buff *skb,
1290                                      unsigned int num)
1291 {
1292         return reciprocal_divide(prandom_u32(), num);
1293 }
1294
1295 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1296                                           struct sk_buff *skb,
1297                                           unsigned int idx, unsigned int skip,
1298                                           unsigned int num)
1299 {
1300         unsigned int i, j;
1301
1302         i = j = min_t(int, f->next[idx], num - 1);
1303         do {
1304                 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1305                         if (i != j)
1306                                 f->next[idx] = i;
1307                         return i;
1308                 }
1309                 if (++i == num)
1310                         i = 0;
1311         } while (i != j);
1312
1313         return idx;
1314 }
1315
1316 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1317 {
1318         return f->flags & (flag >> 8);
1319 }
1320
1321 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1322                              struct packet_type *pt, struct net_device *orig_dev)
1323 {
1324         struct packet_fanout *f = pt->af_packet_priv;
1325         unsigned int num = f->num_members;
1326         struct packet_sock *po;
1327         unsigned int idx;
1328
1329         if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1330             !num) {
1331                 kfree_skb(skb);
1332                 return 0;
1333         }
1334
1335         switch (f->type) {
1336         case PACKET_FANOUT_HASH:
1337         default:
1338                 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1339                         skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1340                         if (!skb)
1341                                 return 0;
1342                 }
1343                 skb_get_hash(skb);
1344                 idx = fanout_demux_hash(f, skb, num);
1345                 break;
1346         case PACKET_FANOUT_LB:
1347                 idx = fanout_demux_lb(f, skb, num);
1348                 break;
1349         case PACKET_FANOUT_CPU:
1350                 idx = fanout_demux_cpu(f, skb, num);
1351                 break;
1352         case PACKET_FANOUT_RND:
1353                 idx = fanout_demux_rnd(f, skb, num);
1354                 break;
1355         case PACKET_FANOUT_ROLLOVER:
1356                 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1357                 break;
1358         }
1359
1360         po = pkt_sk(f->arr[idx]);
1361         if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1362             unlikely(!packet_rcv_has_room(po, skb))) {
1363                 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1364                 po = pkt_sk(f->arr[idx]);
1365         }
1366
1367         return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1368 }
1369
1370 DEFINE_MUTEX(fanout_mutex);
1371 EXPORT_SYMBOL_GPL(fanout_mutex);
1372 static LIST_HEAD(fanout_list);
1373
1374 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1375 {
1376         struct packet_fanout *f = po->fanout;
1377
1378         spin_lock(&f->lock);
1379         f->arr[f->num_members] = sk;
1380         smp_wmb();
1381         f->num_members++;
1382         spin_unlock(&f->lock);
1383 }
1384
1385 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1386 {
1387         struct packet_fanout *f = po->fanout;
1388         int i;
1389
1390         spin_lock(&f->lock);
1391         for (i = 0; i < f->num_members; i++) {
1392                 if (f->arr[i] == sk)
1393                         break;
1394         }
1395         BUG_ON(i >= f->num_members);
1396         f->arr[i] = f->arr[f->num_members - 1];
1397         f->num_members--;
1398         spin_unlock(&f->lock);
1399 }
1400
1401 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1402 {
1403         if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1404                 return true;
1405
1406         return false;
1407 }
1408
1409 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1410 {
1411         struct packet_sock *po = pkt_sk(sk);
1412         struct packet_fanout *f, *match;
1413         u8 type = type_flags & 0xff;
1414         u8 flags = type_flags >> 8;
1415         int err;
1416
1417         switch (type) {
1418         case PACKET_FANOUT_ROLLOVER:
1419                 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1420                         return -EINVAL;
1421         case PACKET_FANOUT_HASH:
1422         case PACKET_FANOUT_LB:
1423         case PACKET_FANOUT_CPU:
1424         case PACKET_FANOUT_RND:
1425                 break;
1426         default:
1427                 return -EINVAL;
1428         }
1429
1430         if (!po->running)
1431                 return -EINVAL;
1432
1433         if (po->fanout)
1434                 return -EALREADY;
1435
1436         mutex_lock(&fanout_mutex);
1437         match = NULL;
1438         list_for_each_entry(f, &fanout_list, list) {
1439                 if (f->id == id &&
1440                     read_pnet(&f->net) == sock_net(sk)) {
1441                         match = f;
1442                         break;
1443                 }
1444         }
1445         err = -EINVAL;
1446         if (match && match->flags != flags)
1447                 goto out;
1448         if (!match) {
1449                 err = -ENOMEM;
1450                 match = kzalloc(sizeof(*match), GFP_KERNEL);
1451                 if (!match)
1452                         goto out;
1453                 write_pnet(&match->net, sock_net(sk));
1454                 match->id = id;
1455                 match->type = type;
1456                 match->flags = flags;
1457                 atomic_set(&match->rr_cur, 0);
1458                 INIT_LIST_HEAD(&match->list);
1459                 spin_lock_init(&match->lock);
1460                 atomic_set(&match->sk_ref, 0);
1461                 match->prot_hook.type = po->prot_hook.type;
1462                 match->prot_hook.dev = po->prot_hook.dev;
1463                 match->prot_hook.func = packet_rcv_fanout;
1464                 match->prot_hook.af_packet_priv = match;
1465                 match->prot_hook.id_match = match_fanout_group;
1466                 dev_add_pack(&match->prot_hook);
1467                 list_add(&match->list, &fanout_list);
1468         }
1469         err = -EINVAL;
1470         if (match->type == type &&
1471             match->prot_hook.type == po->prot_hook.type &&
1472             match->prot_hook.dev == po->prot_hook.dev) {
1473                 err = -ENOSPC;
1474                 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1475                         __dev_remove_pack(&po->prot_hook);
1476                         po->fanout = match;
1477                         atomic_inc(&match->sk_ref);
1478                         __fanout_link(sk, po);
1479                         err = 0;
1480                 }
1481         }
1482 out:
1483         mutex_unlock(&fanout_mutex);
1484         return err;
1485 }
1486
1487 static void fanout_release(struct sock *sk)
1488 {
1489         struct packet_sock *po = pkt_sk(sk);
1490         struct packet_fanout *f;
1491
1492         f = po->fanout;
1493         if (!f)
1494                 return;
1495
1496         mutex_lock(&fanout_mutex);
1497         po->fanout = NULL;
1498
1499         if (atomic_dec_and_test(&f->sk_ref)) {
1500                 list_del(&f->list);
1501                 dev_remove_pack(&f->prot_hook);
1502                 kfree(f);
1503         }
1504         mutex_unlock(&fanout_mutex);
1505 }
1506
1507 static const struct proto_ops packet_ops;
1508
1509 static const struct proto_ops packet_ops_spkt;
1510
1511 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1512                            struct packet_type *pt, struct net_device *orig_dev)
1513 {
1514         struct sock *sk;
1515         struct sockaddr_pkt *spkt;
1516
1517         /*
1518          *      When we registered the protocol we saved the socket in the data
1519          *      field for just this event.
1520          */
1521
1522         sk = pt->af_packet_priv;
1523
1524         /*
1525          *      Yank back the headers [hope the device set this
1526          *      right or kerboom...]
1527          *
1528          *      Incoming packets have ll header pulled,
1529          *      push it back.
1530          *
1531          *      For outgoing ones skb->data == skb_mac_header(skb)
1532          *      so that this procedure is noop.
1533          */
1534
1535         if (skb->pkt_type == PACKET_LOOPBACK)
1536                 goto out;
1537
1538         if (!net_eq(dev_net(dev), sock_net(sk)))
1539                 goto out;
1540
1541         skb = skb_share_check(skb, GFP_ATOMIC);
1542         if (skb == NULL)
1543                 goto oom;
1544
1545         /* drop any routing info */
1546         skb_dst_drop(skb);
1547
1548         /* drop conntrack reference */
1549         nf_reset(skb);
1550
1551         spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1552
1553         skb_push(skb, skb->data - skb_mac_header(skb));
1554
1555         /*
1556          *      The SOCK_PACKET socket receives _all_ frames.
1557          */
1558
1559         spkt->spkt_family = dev->type;
1560         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1561         spkt->spkt_protocol = skb->protocol;
1562
1563         /*
1564          *      Charge the memory to the socket. This is done specifically
1565          *      to prevent sockets using all the memory up.
1566          */
1567
1568         if (sock_queue_rcv_skb(sk, skb) == 0)
1569                 return 0;
1570
1571 out:
1572         kfree_skb(skb);
1573 oom:
1574         return 0;
1575 }
1576
1577
1578 /*
1579  *      Output a raw packet to a device layer. This bypasses all the other
1580  *      protocol layers and you must therefore supply it with a complete frame
1581  */
1582
1583 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1584                                struct msghdr *msg, size_t len)
1585 {
1586         struct sock *sk = sock->sk;
1587         DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1588         struct sk_buff *skb = NULL;
1589         struct net_device *dev;
1590         __be16 proto = 0;
1591         int err;
1592         int extra_len = 0;
1593
1594         /*
1595          *      Get and verify the address.
1596          */
1597
1598         if (saddr) {
1599                 if (msg->msg_namelen < sizeof(struct sockaddr))
1600                         return -EINVAL;
1601                 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1602                         proto = saddr->spkt_protocol;
1603         } else
1604                 return -ENOTCONN;       /* SOCK_PACKET must be sent giving an address */
1605
1606         /*
1607          *      Find the device first to size check it
1608          */
1609
1610         saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1611 retry:
1612         rcu_read_lock();
1613         dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1614         err = -ENODEV;
1615         if (dev == NULL)
1616                 goto out_unlock;
1617
1618         err = -ENETDOWN;
1619         if (!(dev->flags & IFF_UP))
1620                 goto out_unlock;
1621
1622         /*
1623          * You may not queue a frame bigger than the mtu. This is the lowest level
1624          * raw protocol and you must do your own fragmentation at this level.
1625          */
1626
1627         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1628                 if (!netif_supports_nofcs(dev)) {
1629                         err = -EPROTONOSUPPORT;
1630                         goto out_unlock;
1631                 }
1632                 extra_len = 4; /* We're doing our own CRC */
1633         }
1634
1635         err = -EMSGSIZE;
1636         if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1637                 goto out_unlock;
1638
1639         if (!skb) {
1640                 size_t reserved = LL_RESERVED_SPACE(dev);
1641                 int tlen = dev->needed_tailroom;
1642                 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1643
1644                 rcu_read_unlock();
1645                 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1646                 if (skb == NULL)
1647                         return -ENOBUFS;
1648                 /* FIXME: Save some space for broken drivers that write a hard
1649                  * header at transmission time by themselves. PPP is the notable
1650                  * one here. This should really be fixed at the driver level.
1651                  */
1652                 skb_reserve(skb, reserved);
1653                 skb_reset_network_header(skb);
1654
1655                 /* Try to align data part correctly */
1656                 if (hhlen) {
1657                         skb->data -= hhlen;
1658                         skb->tail -= hhlen;
1659                         if (len < hhlen)
1660                                 skb_reset_network_header(skb);
1661                 }
1662                 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1663                 if (err)
1664                         goto out_free;
1665                 goto retry;
1666         }
1667
1668         if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1669                 /* Earlier code assumed this would be a VLAN pkt,
1670                  * double-check this now that we have the actual
1671                  * packet in hand.
1672                  */
1673                 struct ethhdr *ehdr;
1674                 skb_reset_mac_header(skb);
1675                 ehdr = eth_hdr(skb);
1676                 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1677                         err = -EMSGSIZE;
1678                         goto out_unlock;
1679                 }
1680         }
1681
1682         skb->protocol = proto;
1683         skb->dev = dev;
1684         skb->priority = sk->sk_priority;
1685         skb->mark = sk->sk_mark;
1686
1687         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1688
1689         if (unlikely(extra_len == 4))
1690                 skb->no_fcs = 1;
1691
1692         skb_probe_transport_header(skb, 0);
1693
1694         dev_queue_xmit(skb);
1695         rcu_read_unlock();
1696         return len;
1697
1698 out_unlock:
1699         rcu_read_unlock();
1700 out_free:
1701         kfree_skb(skb);
1702         return err;
1703 }
1704
1705 static unsigned int run_filter(const struct sk_buff *skb,
1706                                       const struct sock *sk,
1707                                       unsigned int res)
1708 {
1709         struct sk_filter *filter;
1710
1711         rcu_read_lock();
1712         filter = rcu_dereference(sk->sk_filter);
1713         if (filter != NULL)
1714                 res = SK_RUN_FILTER(filter, skb);
1715         rcu_read_unlock();
1716
1717         return res;
1718 }
1719
1720 /*
1721  * This function makes lazy skb cloning in hope that most of packets
1722  * are discarded by BPF.
1723  *
1724  * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1725  * and skb->cb are mangled. It works because (and until) packets
1726  * falling here are owned by current CPU. Output packets are cloned
1727  * by dev_queue_xmit_nit(), input packets are processed by net_bh
1728  * sequencially, so that if we return skb to original state on exit,
1729  * we will not harm anyone.
1730  */
1731
1732 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1733                       struct packet_type *pt, struct net_device *orig_dev)
1734 {
1735         struct sock *sk;
1736         struct sockaddr_ll *sll;
1737         struct packet_sock *po;
1738         u8 *skb_head = skb->data;
1739         int skb_len = skb->len;
1740         unsigned int snaplen, res;
1741
1742         if (skb->pkt_type == PACKET_LOOPBACK)
1743                 goto drop;
1744
1745         sk = pt->af_packet_priv;
1746         po = pkt_sk(sk);
1747
1748         if (!net_eq(dev_net(dev), sock_net(sk)))
1749                 goto drop;
1750
1751         skb->dev = dev;
1752
1753         if (dev->header_ops) {
1754                 /* The device has an explicit notion of ll header,
1755                  * exported to higher levels.
1756                  *
1757                  * Otherwise, the device hides details of its frame
1758                  * structure, so that corresponding packet head is
1759                  * never delivered to user.
1760                  */
1761                 if (sk->sk_type != SOCK_DGRAM)
1762                         skb_push(skb, skb->data - skb_mac_header(skb));
1763                 else if (skb->pkt_type == PACKET_OUTGOING) {
1764                         /* Special case: outgoing packets have ll header at head */
1765                         skb_pull(skb, skb_network_offset(skb));
1766                 }
1767         }
1768
1769         snaplen = skb->len;
1770
1771         res = run_filter(skb, sk, snaplen);
1772         if (!res)
1773                 goto drop_n_restore;
1774         if (snaplen > res)
1775                 snaplen = res;
1776
1777         if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1778                 goto drop_n_acct;
1779
1780         if (skb_shared(skb)) {
1781                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1782                 if (nskb == NULL)
1783                         goto drop_n_acct;
1784
1785                 if (skb_head != skb->data) {
1786                         skb->data = skb_head;
1787                         skb->len = skb_len;
1788                 }
1789                 consume_skb(skb);
1790                 skb = nskb;
1791         }
1792
1793         BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1794                      sizeof(skb->cb));
1795
1796         sll = &PACKET_SKB_CB(skb)->sa.ll;
1797         sll->sll_family = AF_PACKET;
1798         sll->sll_hatype = dev->type;
1799         sll->sll_protocol = skb->protocol;
1800         sll->sll_pkttype = skb->pkt_type;
1801         if (unlikely(po->origdev))
1802                 sll->sll_ifindex = orig_dev->ifindex;
1803         else
1804                 sll->sll_ifindex = dev->ifindex;
1805
1806         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1807
1808         PACKET_SKB_CB(skb)->origlen = skb->len;
1809
1810         if (pskb_trim(skb, snaplen))
1811                 goto drop_n_acct;
1812
1813         skb_set_owner_r(skb, sk);
1814         skb->dev = NULL;
1815         skb_dst_drop(skb);
1816
1817         /* drop conntrack reference */
1818         nf_reset(skb);
1819
1820         spin_lock(&sk->sk_receive_queue.lock);
1821         po->stats.stats1.tp_packets++;
1822         skb->dropcount = atomic_read(&sk->sk_drops);
1823         __skb_queue_tail(&sk->sk_receive_queue, skb);
1824         spin_unlock(&sk->sk_receive_queue.lock);
1825         sk->sk_data_ready(sk, skb->len);
1826         return 0;
1827
1828 drop_n_acct:
1829         spin_lock(&sk->sk_receive_queue.lock);
1830         po->stats.stats1.tp_drops++;
1831         atomic_inc(&sk->sk_drops);
1832         spin_unlock(&sk->sk_receive_queue.lock);
1833
1834 drop_n_restore:
1835         if (skb_head != skb->data && skb_shared(skb)) {
1836                 skb->data = skb_head;
1837                 skb->len = skb_len;
1838         }
1839 drop:
1840         consume_skb(skb);
1841         return 0;
1842 }
1843
1844 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1845                        struct packet_type *pt, struct net_device *orig_dev)
1846 {
1847         struct sock *sk;
1848         struct packet_sock *po;
1849         struct sockaddr_ll *sll;
1850         union tpacket_uhdr h;
1851         u8 *skb_head = skb->data;
1852         int skb_len = skb->len;
1853         unsigned int snaplen, res;
1854         unsigned long status = TP_STATUS_USER;
1855         unsigned short macoff, netoff, hdrlen;
1856         struct sk_buff *copy_skb = NULL;
1857         struct timespec ts;
1858         __u32 ts_status;
1859
1860         /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
1861          * We may add members to them until current aligned size without forcing
1862          * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
1863          */
1864         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
1865         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
1866
1867         if (skb->pkt_type == PACKET_LOOPBACK)
1868                 goto drop;
1869
1870         sk = pt->af_packet_priv;
1871         po = pkt_sk(sk);
1872
1873         if (!net_eq(dev_net(dev), sock_net(sk)))
1874                 goto drop;
1875
1876         if (dev->header_ops) {
1877                 if (sk->sk_type != SOCK_DGRAM)
1878                         skb_push(skb, skb->data - skb_mac_header(skb));
1879                 else if (skb->pkt_type == PACKET_OUTGOING) {
1880                         /* Special case: outgoing packets have ll header at head */
1881                         skb_pull(skb, skb_network_offset(skb));
1882                 }
1883         }
1884
1885         if (skb->ip_summed == CHECKSUM_PARTIAL)
1886                 status |= TP_STATUS_CSUMNOTREADY;
1887
1888         snaplen = skb->len;
1889
1890         res = run_filter(skb, sk, snaplen);
1891         if (!res)
1892                 goto drop_n_restore;
1893         if (snaplen > res)
1894                 snaplen = res;
1895
1896         if (sk->sk_type == SOCK_DGRAM) {
1897                 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1898                                   po->tp_reserve;
1899         } else {
1900                 unsigned int maclen = skb_network_offset(skb);
1901                 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1902                                        (maclen < 16 ? 16 : maclen)) +
1903                         po->tp_reserve;
1904                 macoff = netoff - maclen;
1905         }
1906         if (po->tp_version <= TPACKET_V2) {
1907                 if (macoff + snaplen > po->rx_ring.frame_size) {
1908                         if (po->copy_thresh &&
1909                             atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1910                                 if (skb_shared(skb)) {
1911                                         copy_skb = skb_clone(skb, GFP_ATOMIC);
1912                                 } else {
1913                                         copy_skb = skb_get(skb);
1914                                         skb_head = skb->data;
1915                                 }
1916                                 if (copy_skb)
1917                                         skb_set_owner_r(copy_skb, sk);
1918                         }
1919                         snaplen = po->rx_ring.frame_size - macoff;
1920                         if ((int)snaplen < 0)
1921                                 snaplen = 0;
1922                 }
1923         }
1924         spin_lock(&sk->sk_receive_queue.lock);
1925         h.raw = packet_current_rx_frame(po, skb,
1926                                         TP_STATUS_KERNEL, (macoff+snaplen));
1927         if (!h.raw)
1928                 goto ring_is_full;
1929         if (po->tp_version <= TPACKET_V2) {
1930                 packet_increment_rx_head(po, &po->rx_ring);
1931         /*
1932          * LOSING will be reported till you read the stats,
1933          * because it's COR - Clear On Read.
1934          * Anyways, moving it for V1/V2 only as V3 doesn't need this
1935          * at packet level.
1936          */
1937                 if (po->stats.stats1.tp_drops)
1938                         status |= TP_STATUS_LOSING;
1939         }
1940         po->stats.stats1.tp_packets++;
1941         if (copy_skb) {
1942                 status |= TP_STATUS_COPY;
1943                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1944         }
1945         spin_unlock(&sk->sk_receive_queue.lock);
1946
1947         skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1948
1949         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1950                 getnstimeofday(&ts);
1951
1952         status |= ts_status;
1953
1954         switch (po->tp_version) {
1955         case TPACKET_V1:
1956                 h.h1->tp_len = skb->len;
1957                 h.h1->tp_snaplen = snaplen;
1958                 h.h1->tp_mac = macoff;
1959                 h.h1->tp_net = netoff;
1960                 h.h1->tp_sec = ts.tv_sec;
1961                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
1962                 hdrlen = sizeof(*h.h1);
1963                 break;
1964         case TPACKET_V2:
1965                 h.h2->tp_len = skb->len;
1966                 h.h2->tp_snaplen = snaplen;
1967                 h.h2->tp_mac = macoff;
1968                 h.h2->tp_net = netoff;
1969                 h.h2->tp_sec = ts.tv_sec;
1970                 h.h2->tp_nsec = ts.tv_nsec;
1971                 if (vlan_tx_tag_present(skb)) {
1972                         h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1973                         h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
1974                         status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1975                 } else {
1976                         h.h2->tp_vlan_tci = 0;
1977                         h.h2->tp_vlan_tpid = 0;
1978                 }
1979                 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
1980                 hdrlen = sizeof(*h.h2);
1981                 break;
1982         case TPACKET_V3:
1983                 /* tp_nxt_offset,vlan are already populated above.
1984                  * So DONT clear those fields here
1985                  */
1986                 h.h3->tp_status |= status;
1987                 h.h3->tp_len = skb->len;
1988                 h.h3->tp_snaplen = snaplen;
1989                 h.h3->tp_mac = macoff;
1990                 h.h3->tp_net = netoff;
1991                 h.h3->tp_sec  = ts.tv_sec;
1992                 h.h3->tp_nsec = ts.tv_nsec;
1993                 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
1994                 hdrlen = sizeof(*h.h3);
1995                 break;
1996         default:
1997                 BUG();
1998         }
1999
2000         sll = h.raw + TPACKET_ALIGN(hdrlen);
2001         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2002         sll->sll_family = AF_PACKET;
2003         sll->sll_hatype = dev->type;
2004         sll->sll_protocol = skb->protocol;
2005         sll->sll_pkttype = skb->pkt_type;
2006         if (unlikely(po->origdev))
2007                 sll->sll_ifindex = orig_dev->ifindex;
2008         else
2009                 sll->sll_ifindex = dev->ifindex;
2010
2011         smp_mb();
2012
2013 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2014         if (po->tp_version <= TPACKET_V2) {
2015                 u8 *start, *end;
2016
2017                 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2018                                         macoff + snaplen);
2019
2020                 for (start = h.raw; start < end; start += PAGE_SIZE)
2021                         flush_dcache_page(pgv_to_page(start));
2022         }
2023         smp_wmb();
2024 #endif
2025
2026         if (po->tp_version <= TPACKET_V2)
2027                 __packet_set_status(po, h.raw, status);
2028         else
2029                 prb_clear_blk_fill_status(&po->rx_ring);
2030
2031         sk->sk_data_ready(sk, 0);
2032
2033 drop_n_restore:
2034         if (skb_head != skb->data && skb_shared(skb)) {
2035                 skb->data = skb_head;
2036                 skb->len = skb_len;
2037         }
2038 drop:
2039         kfree_skb(skb);
2040         return 0;
2041
2042 ring_is_full:
2043         po->stats.stats1.tp_drops++;
2044         spin_unlock(&sk->sk_receive_queue.lock);
2045
2046         sk->sk_data_ready(sk, 0);
2047         kfree_skb(copy_skb);
2048         goto drop_n_restore;
2049 }
2050
2051 static void tpacket_destruct_skb(struct sk_buff *skb)
2052 {
2053         struct packet_sock *po = pkt_sk(skb->sk);
2054
2055         if (likely(po->tx_ring.pg_vec)) {
2056                 void *ph;
2057                 __u32 ts;
2058
2059                 ph = skb_shinfo(skb)->destructor_arg;
2060                 packet_dec_pending(&po->tx_ring);
2061
2062                 ts = __packet_set_timestamp(po, ph, skb);
2063                 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2064         }
2065
2066         sock_wfree(skb);
2067 }
2068
2069 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2070                 void *frame, struct net_device *dev, int size_max,
2071                 __be16 proto, unsigned char *addr, int hlen)
2072 {
2073         union tpacket_uhdr ph;
2074         int to_write, offset, len, tp_len, nr_frags, len_max;
2075         struct socket *sock = po->sk.sk_socket;
2076         struct page *page;
2077         void *data;
2078         int err;
2079
2080         ph.raw = frame;
2081
2082         skb->protocol = proto;
2083         skb->dev = dev;
2084         skb->priority = po->sk.sk_priority;
2085         skb->mark = po->sk.sk_mark;
2086         sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2087         skb_shinfo(skb)->destructor_arg = ph.raw;
2088
2089         switch (po->tp_version) {
2090         case TPACKET_V2:
2091                 tp_len = ph.h2->tp_len;
2092                 break;
2093         default:
2094                 tp_len = ph.h1->tp_len;
2095                 break;
2096         }
2097         if (unlikely(tp_len > size_max)) {
2098                 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2099                 return -EMSGSIZE;
2100         }
2101
2102         skb_reserve(skb, hlen);
2103         skb_reset_network_header(skb);
2104
2105         if (!packet_use_direct_xmit(po))
2106                 skb_probe_transport_header(skb, 0);
2107         if (unlikely(po->tp_tx_has_off)) {
2108                 int off_min, off_max, off;
2109                 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2110                 off_max = po->tx_ring.frame_size - tp_len;
2111                 if (sock->type == SOCK_DGRAM) {
2112                         switch (po->tp_version) {
2113                         case TPACKET_V2:
2114                                 off = ph.h2->tp_net;
2115                                 break;
2116                         default:
2117                                 off = ph.h1->tp_net;
2118                                 break;
2119                         }
2120                 } else {
2121                         switch (po->tp_version) {
2122                         case TPACKET_V2:
2123                                 off = ph.h2->tp_mac;
2124                                 break;
2125                         default:
2126                                 off = ph.h1->tp_mac;
2127                                 break;
2128                         }
2129                 }
2130                 if (unlikely((off < off_min) || (off_max < off)))
2131                         return -EINVAL;
2132                 data = ph.raw + off;
2133         } else {
2134                 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2135         }
2136         to_write = tp_len;
2137
2138         if (sock->type == SOCK_DGRAM) {
2139                 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2140                                 NULL, tp_len);
2141                 if (unlikely(err < 0))
2142                         return -EINVAL;
2143         } else if (dev->hard_header_len) {
2144                 /* net device doesn't like empty head */
2145                 if (unlikely(tp_len <= dev->hard_header_len)) {
2146                         pr_err("packet size is too short (%d < %d)\n",
2147                                tp_len, dev->hard_header_len);
2148                         return -EINVAL;
2149                 }
2150
2151                 skb_push(skb, dev->hard_header_len);
2152                 err = skb_store_bits(skb, 0, data,
2153                                 dev->hard_header_len);
2154                 if (unlikely(err))
2155                         return err;
2156
2157                 data += dev->hard_header_len;
2158                 to_write -= dev->hard_header_len;
2159         }
2160
2161         offset = offset_in_page(data);
2162         len_max = PAGE_SIZE - offset;
2163         len = ((to_write > len_max) ? len_max : to_write);
2164
2165         skb->data_len = to_write;
2166         skb->len += to_write;
2167         skb->truesize += to_write;
2168         atomic_add(to_write, &po->sk.sk_wmem_alloc);
2169
2170         while (likely(to_write)) {
2171                 nr_frags = skb_shinfo(skb)->nr_frags;
2172
2173                 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2174                         pr_err("Packet exceed the number of skb frags(%lu)\n",
2175                                MAX_SKB_FRAGS);
2176                         return -EFAULT;
2177                 }
2178
2179                 page = pgv_to_page(data);
2180                 data += len;
2181                 flush_dcache_page(page);
2182                 get_page(page);
2183                 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2184                 to_write -= len;
2185                 offset = 0;
2186                 len_max = PAGE_SIZE;
2187                 len = ((to_write > len_max) ? len_max : to_write);
2188         }
2189
2190         return tp_len;
2191 }
2192
2193 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2194 {
2195         struct sk_buff *skb;
2196         struct net_device *dev;
2197         __be16 proto;
2198         int err, reserve = 0;
2199         void *ph;
2200         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2201         bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2202         int tp_len, size_max;
2203         unsigned char *addr;
2204         int len_sum = 0;
2205         int status = TP_STATUS_AVAILABLE;
2206         int hlen, tlen;
2207
2208         mutex_lock(&po->pg_vec_lock);
2209
2210         if (likely(saddr == NULL)) {
2211                 dev     = packet_cached_dev_get(po);
2212                 proto   = po->num;
2213                 addr    = NULL;
2214         } else {
2215                 err = -EINVAL;
2216                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2217                         goto out;
2218                 if (msg->msg_namelen < (saddr->sll_halen
2219                                         + offsetof(struct sockaddr_ll,
2220                                                 sll_addr)))
2221                         goto out;
2222                 proto   = saddr->sll_protocol;
2223                 addr    = saddr->sll_addr;
2224                 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2225         }
2226
2227         err = -ENXIO;
2228         if (unlikely(dev == NULL))
2229                 goto out;
2230         err = -ENETDOWN;
2231         if (unlikely(!(dev->flags & IFF_UP)))
2232                 goto out_put;
2233
2234         reserve = dev->hard_header_len;
2235
2236         size_max = po->tx_ring.frame_size
2237                 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2238
2239         if (size_max > dev->mtu + reserve)
2240                 size_max = dev->mtu + reserve;
2241
2242         do {
2243                 ph = packet_current_frame(po, &po->tx_ring,
2244                                           TP_STATUS_SEND_REQUEST);
2245                 if (unlikely(ph == NULL)) {
2246                         if (need_wait && need_resched())
2247                                 schedule();
2248                         continue;
2249                 }
2250
2251                 status = TP_STATUS_SEND_REQUEST;
2252                 hlen = LL_RESERVED_SPACE(dev);
2253                 tlen = dev->needed_tailroom;
2254                 skb = sock_alloc_send_skb(&po->sk,
2255                                 hlen + tlen + sizeof(struct sockaddr_ll),
2256                                 0, &err);
2257
2258                 if (unlikely(skb == NULL))
2259                         goto out_status;
2260
2261                 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2262                                 addr, hlen);
2263
2264                 if (unlikely(tp_len < 0)) {
2265                         if (po->tp_loss) {
2266                                 __packet_set_status(po, ph,
2267                                                 TP_STATUS_AVAILABLE);
2268                                 packet_increment_head(&po->tx_ring);
2269                                 kfree_skb(skb);
2270                                 continue;
2271                         } else {
2272                                 status = TP_STATUS_WRONG_FORMAT;
2273                                 err = tp_len;
2274                                 goto out_status;
2275                         }
2276                 }
2277
2278                 skb_set_queue_mapping(skb, packet_pick_tx_queue(dev));
2279                 skb->destructor = tpacket_destruct_skb;
2280                 __packet_set_status(po, ph, TP_STATUS_SENDING);
2281                 packet_inc_pending(&po->tx_ring);
2282
2283                 status = TP_STATUS_SEND_REQUEST;
2284                 err = po->xmit(skb);
2285                 if (unlikely(err > 0)) {
2286                         err = net_xmit_errno(err);
2287                         if (err && __packet_get_status(po, ph) ==
2288                                    TP_STATUS_AVAILABLE) {
2289                                 /* skb was destructed already */
2290                                 skb = NULL;
2291                                 goto out_status;
2292                         }
2293                         /*
2294                          * skb was dropped but not destructed yet;
2295                          * let's treat it like congestion or err < 0
2296                          */
2297                         err = 0;
2298                 }
2299                 packet_increment_head(&po->tx_ring);
2300                 len_sum += tp_len;
2301         } while (likely((ph != NULL) ||
2302                 /* Note: packet_read_pending() might be slow if we have
2303                  * to call it as it's per_cpu variable, but in fast-path
2304                  * we already short-circuit the loop with the first
2305                  * condition, and luckily don't have to go that path
2306                  * anyway.
2307                  */
2308                  (need_wait && packet_read_pending(&po->tx_ring))));
2309
2310         err = len_sum;
2311         goto out_put;
2312
2313 out_status:
2314         __packet_set_status(po, ph, status);
2315         kfree_skb(skb);
2316 out_put:
2317         dev_put(dev);
2318 out:
2319         mutex_unlock(&po->pg_vec_lock);
2320         return err;
2321 }
2322
2323 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2324                                         size_t reserve, size_t len,
2325                                         size_t linear, int noblock,
2326                                         int *err)
2327 {
2328         struct sk_buff *skb;
2329
2330         /* Under a page?  Don't bother with paged skb. */
2331         if (prepad + len < PAGE_SIZE || !linear)
2332                 linear = len;
2333
2334         skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2335                                    err, 0);
2336         if (!skb)
2337                 return NULL;
2338
2339         skb_reserve(skb, reserve);
2340         skb_put(skb, linear);
2341         skb->data_len = len - linear;
2342         skb->len += len - linear;
2343
2344         return skb;
2345 }
2346
2347 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2348 {
2349         struct sock *sk = sock->sk;
2350         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2351         struct sk_buff *skb;
2352         struct net_device *dev;
2353         __be16 proto;
2354         unsigned char *addr;
2355         int err, reserve = 0;
2356         struct virtio_net_hdr vnet_hdr = { 0 };
2357         int offset = 0;
2358         int vnet_hdr_len;
2359         struct packet_sock *po = pkt_sk(sk);
2360         unsigned short gso_type = 0;
2361         int hlen, tlen;
2362         int extra_len = 0;
2363
2364         /*
2365          *      Get and verify the address.
2366          */
2367
2368         if (likely(saddr == NULL)) {
2369                 dev     = packet_cached_dev_get(po);
2370                 proto   = po->num;
2371                 addr    = NULL;
2372         } else {
2373                 err = -EINVAL;
2374                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2375                         goto out;
2376                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2377                         goto out;
2378                 proto   = saddr->sll_protocol;
2379                 addr    = saddr->sll_addr;
2380                 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2381         }
2382
2383         err = -ENXIO;
2384         if (unlikely(dev == NULL))
2385                 goto out_unlock;
2386         err = -ENETDOWN;
2387         if (unlikely(!(dev->flags & IFF_UP)))
2388                 goto out_unlock;
2389
2390         if (sock->type == SOCK_RAW)
2391                 reserve = dev->hard_header_len;
2392         if (po->has_vnet_hdr) {
2393                 vnet_hdr_len = sizeof(vnet_hdr);
2394
2395                 err = -EINVAL;
2396                 if (len < vnet_hdr_len)
2397                         goto out_unlock;
2398
2399                 len -= vnet_hdr_len;
2400
2401                 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2402                                        vnet_hdr_len);
2403                 if (err < 0)
2404                         goto out_unlock;
2405
2406                 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2407                     (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2408                       vnet_hdr.hdr_len))
2409                         vnet_hdr.hdr_len = vnet_hdr.csum_start +
2410                                                  vnet_hdr.csum_offset + 2;
2411
2412                 err = -EINVAL;
2413                 if (vnet_hdr.hdr_len > len)
2414                         goto out_unlock;
2415
2416                 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2417                         switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2418                         case VIRTIO_NET_HDR_GSO_TCPV4:
2419                                 gso_type = SKB_GSO_TCPV4;
2420                                 break;
2421                         case VIRTIO_NET_HDR_GSO_TCPV6:
2422                                 gso_type = SKB_GSO_TCPV6;
2423                                 break;
2424                         case VIRTIO_NET_HDR_GSO_UDP:
2425                                 gso_type = SKB_GSO_UDP;
2426                                 break;
2427                         default:
2428                                 goto out_unlock;
2429                         }
2430
2431                         if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2432                                 gso_type |= SKB_GSO_TCP_ECN;
2433
2434                         if (vnet_hdr.gso_size == 0)
2435                                 goto out_unlock;
2436
2437                 }
2438         }
2439
2440         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2441                 if (!netif_supports_nofcs(dev)) {
2442                         err = -EPROTONOSUPPORT;
2443                         goto out_unlock;
2444                 }
2445                 extra_len = 4; /* We're doing our own CRC */
2446         }
2447
2448         err = -EMSGSIZE;
2449         if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2450                 goto out_unlock;
2451
2452         err = -ENOBUFS;
2453         hlen = LL_RESERVED_SPACE(dev);
2454         tlen = dev->needed_tailroom;
2455         skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2456                                msg->msg_flags & MSG_DONTWAIT, &err);
2457         if (skb == NULL)
2458                 goto out_unlock;
2459
2460         skb_set_network_header(skb, reserve);
2461
2462         err = -EINVAL;
2463         if (sock->type == SOCK_DGRAM &&
2464             (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2465                 goto out_free;
2466
2467         /* Returns -EFAULT on error */
2468         err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2469         if (err)
2470                 goto out_free;
2471
2472         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2473
2474         if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2475                 /* Earlier code assumed this would be a VLAN pkt,
2476                  * double-check this now that we have the actual
2477                  * packet in hand.
2478                  */
2479                 struct ethhdr *ehdr;
2480                 skb_reset_mac_header(skb);
2481                 ehdr = eth_hdr(skb);
2482                 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2483                         err = -EMSGSIZE;
2484                         goto out_free;
2485                 }
2486         }
2487
2488         skb->protocol = proto;
2489         skb->dev = dev;
2490         skb->priority = sk->sk_priority;
2491         skb->mark = sk->sk_mark;
2492         skb_set_queue_mapping(skb, packet_pick_tx_queue(dev));
2493
2494         if (po->has_vnet_hdr) {
2495                 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2496                         if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2497                                                   vnet_hdr.csum_offset)) {
2498                                 err = -EINVAL;
2499                                 goto out_free;
2500                         }
2501                 }
2502
2503                 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2504                 skb_shinfo(skb)->gso_type = gso_type;
2505
2506                 /* Header must be checked, and gso_segs computed. */
2507                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2508                 skb_shinfo(skb)->gso_segs = 0;
2509
2510                 len += vnet_hdr_len;
2511         }
2512
2513         if (!packet_use_direct_xmit(po))
2514                 skb_probe_transport_header(skb, reserve);
2515         if (unlikely(extra_len == 4))
2516                 skb->no_fcs = 1;
2517
2518         err = po->xmit(skb);
2519         if (err > 0 && (err = net_xmit_errno(err)) != 0)
2520                 goto out_unlock;
2521
2522         dev_put(dev);
2523
2524         return len;
2525
2526 out_free:
2527         kfree_skb(skb);
2528 out_unlock:
2529         if (dev)
2530                 dev_put(dev);
2531 out:
2532         return err;
2533 }
2534
2535 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2536                 struct msghdr *msg, size_t len)
2537 {
2538         struct sock *sk = sock->sk;
2539         struct packet_sock *po = pkt_sk(sk);
2540
2541         if (po->tx_ring.pg_vec)
2542                 return tpacket_snd(po, msg);
2543         else
2544                 return packet_snd(sock, msg, len);
2545 }
2546
2547 /*
2548  *      Close a PACKET socket. This is fairly simple. We immediately go
2549  *      to 'closed' state and remove our protocol entry in the device list.
2550  */
2551
2552 static int packet_release(struct socket *sock)
2553 {
2554         struct sock *sk = sock->sk;
2555         struct packet_sock *po;
2556         struct net *net;
2557         union tpacket_req_u req_u;
2558
2559         if (!sk)
2560                 return 0;
2561
2562         net = sock_net(sk);
2563         po = pkt_sk(sk);
2564
2565         mutex_lock(&net->packet.sklist_lock);
2566         sk_del_node_init_rcu(sk);
2567         mutex_unlock(&net->packet.sklist_lock);
2568
2569         preempt_disable();
2570         sock_prot_inuse_add(net, sk->sk_prot, -1);
2571         preempt_enable();
2572
2573         spin_lock(&po->bind_lock);
2574         unregister_prot_hook(sk, false);
2575         packet_cached_dev_reset(po);
2576
2577         if (po->prot_hook.dev) {
2578                 dev_put(po->prot_hook.dev);
2579                 po->prot_hook.dev = NULL;
2580         }
2581         spin_unlock(&po->bind_lock);
2582
2583         packet_flush_mclist(sk);
2584
2585         if (po->rx_ring.pg_vec) {
2586                 memset(&req_u, 0, sizeof(req_u));
2587                 packet_set_ring(sk, &req_u, 1, 0);
2588         }
2589
2590         if (po->tx_ring.pg_vec) {
2591                 memset(&req_u, 0, sizeof(req_u));
2592                 packet_set_ring(sk, &req_u, 1, 1);
2593         }
2594
2595         fanout_release(sk);
2596
2597         synchronize_net();
2598         /*
2599          *      Now the socket is dead. No more input will appear.
2600          */
2601         sock_orphan(sk);
2602         sock->sk = NULL;
2603
2604         /* Purge queues */
2605
2606         skb_queue_purge(&sk->sk_receive_queue);
2607         packet_free_pending(po);
2608         sk_refcnt_debug_release(sk);
2609
2610         sock_put(sk);
2611         return 0;
2612 }
2613
2614 /*
2615  *      Attach a packet hook.
2616  */
2617
2618 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2619 {
2620         struct packet_sock *po = pkt_sk(sk);
2621         const struct net_device *dev_curr;
2622         __be16 proto_curr;
2623         bool need_rehook;
2624
2625         if (po->fanout) {
2626                 if (dev)
2627                         dev_put(dev);
2628
2629                 return -EINVAL;
2630         }
2631
2632         lock_sock(sk);
2633         spin_lock(&po->bind_lock);
2634
2635         proto_curr = po->prot_hook.type;
2636         dev_curr = po->prot_hook.dev;
2637
2638         need_rehook = proto_curr != proto || dev_curr != dev;
2639
2640         if (need_rehook) {
2641                 unregister_prot_hook(sk, true);
2642
2643                 po->num = proto;
2644                 po->prot_hook.type = proto;
2645
2646                 if (po->prot_hook.dev)
2647                         dev_put(po->prot_hook.dev);
2648
2649                 po->prot_hook.dev = dev;
2650
2651                 po->ifindex = dev ? dev->ifindex : 0;
2652                 packet_cached_dev_assign(po, dev);
2653         }
2654
2655         if (proto == 0 || !need_rehook)
2656                 goto out_unlock;
2657
2658         if (!dev || (dev->flags & IFF_UP)) {
2659                 register_prot_hook(sk);
2660         } else {
2661                 sk->sk_err = ENETDOWN;
2662                 if (!sock_flag(sk, SOCK_DEAD))
2663                         sk->sk_error_report(sk);
2664         }
2665
2666 out_unlock:
2667         spin_unlock(&po->bind_lock);
2668         release_sock(sk);
2669         return 0;
2670 }
2671
2672 /*
2673  *      Bind a packet socket to a device
2674  */
2675
2676 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2677                             int addr_len)
2678 {
2679         struct sock *sk = sock->sk;
2680         char name[15];
2681         struct net_device *dev;
2682         int err = -ENODEV;
2683
2684         /*
2685          *      Check legality
2686          */
2687
2688         if (addr_len != sizeof(struct sockaddr))
2689                 return -EINVAL;
2690         strlcpy(name, uaddr->sa_data, sizeof(name));
2691
2692         dev = dev_get_by_name(sock_net(sk), name);
2693         if (dev)
2694                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2695         return err;
2696 }
2697
2698 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2699 {
2700         struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2701         struct sock *sk = sock->sk;
2702         struct net_device *dev = NULL;
2703         int err;
2704
2705
2706         /*
2707          *      Check legality
2708          */
2709
2710         if (addr_len < sizeof(struct sockaddr_ll))
2711                 return -EINVAL;
2712         if (sll->sll_family != AF_PACKET)
2713                 return -EINVAL;
2714
2715         if (sll->sll_ifindex) {
2716                 err = -ENODEV;
2717                 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2718                 if (dev == NULL)
2719                         goto out;
2720         }
2721         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2722
2723 out:
2724         return err;
2725 }
2726
2727 static struct proto packet_proto = {
2728         .name     = "PACKET",
2729         .owner    = THIS_MODULE,
2730         .obj_size = sizeof(struct packet_sock),
2731 };
2732
2733 /*
2734  *      Create a packet of type SOCK_PACKET.
2735  */
2736
2737 static int packet_create(struct net *net, struct socket *sock, int protocol,
2738                          int kern)
2739 {
2740         struct sock *sk;
2741         struct packet_sock *po;
2742         __be16 proto = (__force __be16)protocol; /* weird, but documented */
2743         int err;
2744
2745         if (!ns_capable(net->user_ns, CAP_NET_RAW))
2746                 return -EPERM;
2747         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2748             sock->type != SOCK_PACKET)
2749                 return -ESOCKTNOSUPPORT;
2750
2751         sock->state = SS_UNCONNECTED;
2752
2753         err = -ENOBUFS;
2754         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2755         if (sk == NULL)
2756                 goto out;
2757
2758         sock->ops = &packet_ops;
2759         if (sock->type == SOCK_PACKET)
2760                 sock->ops = &packet_ops_spkt;
2761
2762         sock_init_data(sock, sk);
2763
2764         po = pkt_sk(sk);
2765         sk->sk_family = PF_PACKET;
2766         po->num = proto;
2767         po->xmit = dev_queue_xmit;
2768
2769         err = packet_alloc_pending(po);
2770         if (err)
2771                 goto out2;
2772
2773         packet_cached_dev_reset(po);
2774
2775         sk->sk_destruct = packet_sock_destruct;
2776         sk_refcnt_debug_inc(sk);
2777
2778         /*
2779          *      Attach a protocol block
2780          */
2781
2782         spin_lock_init(&po->bind_lock);
2783         mutex_init(&po->pg_vec_lock);
2784         po->prot_hook.func = packet_rcv;
2785
2786         if (sock->type == SOCK_PACKET)
2787                 po->prot_hook.func = packet_rcv_spkt;
2788
2789         po->prot_hook.af_packet_priv = sk;
2790
2791         if (proto) {
2792                 po->prot_hook.type = proto;
2793                 register_prot_hook(sk);
2794         }
2795
2796         mutex_lock(&net->packet.sklist_lock);
2797         sk_add_node_rcu(sk, &net->packet.sklist);
2798         mutex_unlock(&net->packet.sklist_lock);
2799
2800         preempt_disable();
2801         sock_prot_inuse_add(net, &packet_proto, 1);
2802         preempt_enable();
2803
2804         return 0;
2805 out2:
2806         sk_free(sk);
2807 out:
2808         return err;
2809 }
2810
2811 /*
2812  *      Pull a packet from our receive queue and hand it to the user.
2813  *      If necessary we block.
2814  */
2815
2816 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2817                           struct msghdr *msg, size_t len, int flags)
2818 {
2819         struct sock *sk = sock->sk;
2820         struct sk_buff *skb;
2821         int copied, err;
2822         int vnet_hdr_len = 0;
2823
2824         err = -EINVAL;
2825         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2826                 goto out;
2827
2828 #if 0
2829         /* What error should we return now? EUNATTACH? */
2830         if (pkt_sk(sk)->ifindex < 0)
2831                 return -ENODEV;
2832 #endif
2833
2834         if (flags & MSG_ERRQUEUE) {
2835                 err = sock_recv_errqueue(sk, msg, len,
2836                                          SOL_PACKET, PACKET_TX_TIMESTAMP);
2837                 goto out;
2838         }
2839
2840         /*
2841          *      Call the generic datagram receiver. This handles all sorts
2842          *      of horrible races and re-entrancy so we can forget about it
2843          *      in the protocol layers.
2844          *
2845          *      Now it will return ENETDOWN, if device have just gone down,
2846          *      but then it will block.
2847          */
2848
2849         skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2850
2851         /*
2852          *      An error occurred so return it. Because skb_recv_datagram()
2853          *      handles the blocking we don't see and worry about blocking
2854          *      retries.
2855          */
2856
2857         if (skb == NULL)
2858                 goto out;
2859
2860         if (pkt_sk(sk)->has_vnet_hdr) {
2861                 struct virtio_net_hdr vnet_hdr = { 0 };
2862
2863                 err = -EINVAL;
2864                 vnet_hdr_len = sizeof(vnet_hdr);
2865                 if (len < vnet_hdr_len)
2866                         goto out_free;
2867
2868                 len -= vnet_hdr_len;
2869
2870                 if (skb_is_gso(skb)) {
2871                         struct skb_shared_info *sinfo = skb_shinfo(skb);
2872
2873                         /* This is a hint as to how much should be linear. */
2874                         vnet_hdr.hdr_len = skb_headlen(skb);
2875                         vnet_hdr.gso_size = sinfo->gso_size;
2876                         if (sinfo->gso_type & SKB_GSO_TCPV4)
2877                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2878                         else if (sinfo->gso_type & SKB_GSO_TCPV6)
2879                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2880                         else if (sinfo->gso_type & SKB_GSO_UDP)
2881                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2882                         else if (sinfo->gso_type & SKB_GSO_FCOE)
2883                                 goto out_free;
2884                         else
2885                                 BUG();
2886                         if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2887                                 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2888                 } else
2889                         vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2890
2891                 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2892                         vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2893                         vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2894                         vnet_hdr.csum_offset = skb->csum_offset;
2895                 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2896                         vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2897                 } /* else everything is zero */
2898
2899                 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2900                                      vnet_hdr_len);
2901                 if (err < 0)
2902                         goto out_free;
2903         }
2904
2905         /* You lose any data beyond the buffer you gave. If it worries
2906          * a user program they can ask the device for its MTU
2907          * anyway.
2908          */
2909         copied = skb->len;
2910         if (copied > len) {
2911                 copied = len;
2912                 msg->msg_flags |= MSG_TRUNC;
2913         }
2914
2915         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2916         if (err)
2917                 goto out_free;
2918
2919         sock_recv_ts_and_drops(msg, sk, skb);
2920
2921         if (msg->msg_name) {
2922                 /* If the address length field is there to be filled
2923                  * in, we fill it in now.
2924                  */
2925                 if (sock->type == SOCK_PACKET) {
2926                         __sockaddr_check_size(sizeof(struct sockaddr_pkt));
2927                         msg->msg_namelen = sizeof(struct sockaddr_pkt);
2928                 } else {
2929                         struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2930                         msg->msg_namelen = sll->sll_halen +
2931                                 offsetof(struct sockaddr_ll, sll_addr);
2932                 }
2933                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2934                        msg->msg_namelen);
2935         }
2936
2937         if (pkt_sk(sk)->auxdata) {
2938                 struct tpacket_auxdata aux;
2939
2940                 aux.tp_status = TP_STATUS_USER;
2941                 if (skb->ip_summed == CHECKSUM_PARTIAL)
2942                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2943                 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2944                 aux.tp_snaplen = skb->len;
2945                 aux.tp_mac = 0;
2946                 aux.tp_net = skb_network_offset(skb);
2947                 if (vlan_tx_tag_present(skb)) {
2948                         aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2949                         aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
2950                         aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2951                 } else {
2952                         aux.tp_vlan_tci = 0;
2953                         aux.tp_vlan_tpid = 0;
2954                 }
2955                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2956         }
2957
2958         /*
2959          *      Free or return the buffer as appropriate. Again this
2960          *      hides all the races and re-entrancy issues from us.
2961          */
2962         err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2963
2964 out_free:
2965         skb_free_datagram(sk, skb);
2966 out:
2967         return err;
2968 }
2969
2970 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2971                                int *uaddr_len, int peer)
2972 {
2973         struct net_device *dev;
2974         struct sock *sk = sock->sk;
2975
2976         if (peer)
2977                 return -EOPNOTSUPP;
2978
2979         uaddr->sa_family = AF_PACKET;
2980         memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
2981         rcu_read_lock();
2982         dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2983         if (dev)
2984                 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
2985         rcu_read_unlock();
2986         *uaddr_len = sizeof(*uaddr);
2987
2988         return 0;
2989 }
2990
2991 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2992                           int *uaddr_len, int peer)
2993 {
2994         struct net_device *dev;
2995         struct sock *sk = sock->sk;
2996         struct packet_sock *po = pkt_sk(sk);
2997         DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2998
2999         if (peer)
3000                 return -EOPNOTSUPP;
3001
3002         sll->sll_family = AF_PACKET;
3003         sll->sll_ifindex = po->ifindex;
3004         sll->sll_protocol = po->num;
3005         sll->sll_pkttype = 0;
3006         rcu_read_lock();
3007         dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3008         if (dev) {
3009                 sll->sll_hatype = dev->type;
3010                 sll->sll_halen = dev->addr_len;
3011                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3012         } else {
3013                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
3014                 sll->sll_halen = 0;
3015         }
3016         rcu_read_unlock();
3017         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3018
3019         return 0;
3020 }
3021
3022 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3023                          int what)
3024 {
3025         switch (i->type) {
3026         case PACKET_MR_MULTICAST:
3027                 if (i->alen != dev->addr_len)
3028                         return -EINVAL;
3029                 if (what > 0)
3030                         return dev_mc_add(dev, i->addr);
3031                 else
3032                         return dev_mc_del(dev, i->addr);
3033                 break;
3034         case PACKET_MR_PROMISC:
3035                 return dev_set_promiscuity(dev, what);
3036                 break;
3037         case PACKET_MR_ALLMULTI:
3038                 return dev_set_allmulti(dev, what);
3039                 break;
3040         case PACKET_MR_UNICAST:
3041                 if (i->alen != dev->addr_len)
3042                         return -EINVAL;
3043                 if (what > 0)
3044                         return dev_uc_add(dev, i->addr);
3045                 else
3046                         return dev_uc_del(dev, i->addr);
3047                 break;
3048         default:
3049                 break;
3050         }
3051         return 0;
3052 }
3053
3054 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
3055 {
3056         for ( ; i; i = i->next) {
3057                 if (i->ifindex == dev->ifindex)
3058                         packet_dev_mc(dev, i, what);
3059         }
3060 }
3061
3062 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3063 {
3064         struct packet_sock *po = pkt_sk(sk);
3065         struct packet_mclist *ml, *i;
3066         struct net_device *dev;
3067         int err;
3068
3069         rtnl_lock();
3070
3071         err = -ENODEV;
3072         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3073         if (!dev)
3074                 goto done;
3075
3076         err = -EINVAL;
3077         if (mreq->mr_alen > dev->addr_len)
3078                 goto done;
3079
3080         err = -ENOBUFS;
3081         i = kmalloc(sizeof(*i), GFP_KERNEL);
3082         if (i == NULL)
3083                 goto done;
3084
3085         err = 0;
3086         for (ml = po->mclist; ml; ml = ml->next) {
3087                 if (ml->ifindex == mreq->mr_ifindex &&
3088                     ml->type == mreq->mr_type &&
3089                     ml->alen == mreq->mr_alen &&
3090                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3091                         ml->count++;
3092                         /* Free the new element ... */
3093                         kfree(i);
3094                         goto done;
3095                 }
3096         }
3097
3098         i->type = mreq->mr_type;
3099         i->ifindex = mreq->mr_ifindex;
3100         i->alen = mreq->mr_alen;
3101         memcpy(i->addr, mreq->mr_address, i->alen);
3102         i->count = 1;
3103         i->next = po->mclist;
3104         po->mclist = i;
3105         err = packet_dev_mc(dev, i, 1);
3106         if (err) {
3107                 po->mclist = i->next;
3108                 kfree(i);
3109         }
3110
3111 done:
3112         rtnl_unlock();
3113         return err;
3114 }
3115
3116 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3117 {
3118         struct packet_mclist *ml, **mlp;
3119
3120         rtnl_lock();
3121
3122         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3123                 if (ml->ifindex == mreq->mr_ifindex &&
3124                     ml->type == mreq->mr_type &&
3125                     ml->alen == mreq->mr_alen &&
3126                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3127                         if (--ml->count == 0) {
3128                                 struct net_device *dev;
3129                                 *mlp = ml->next;
3130                                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3131                                 if (dev)
3132                                         packet_dev_mc(dev, ml, -1);
3133                                 kfree(ml);
3134                         }
3135                         rtnl_unlock();
3136                         return 0;
3137                 }
3138         }
3139         rtnl_unlock();
3140         return -EADDRNOTAVAIL;
3141 }
3142
3143 static void packet_flush_mclist(struct sock *sk)
3144 {
3145         struct packet_sock *po = pkt_sk(sk);
3146         struct packet_mclist *ml;
3147
3148         if (!po->mclist)
3149                 return;
3150
3151         rtnl_lock();
3152         while ((ml = po->mclist) != NULL) {
3153                 struct net_device *dev;
3154
3155                 po->mclist = ml->next;
3156                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3157                 if (dev != NULL)
3158                         packet_dev_mc(dev, ml, -1);
3159                 kfree(ml);
3160         }
3161         rtnl_unlock();
3162 }
3163
3164 static int
3165 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3166 {
3167         struct sock *sk = sock->sk;
3168         struct packet_sock *po = pkt_sk(sk);
3169         int ret;
3170
3171         if (level != SOL_PACKET)
3172                 return -ENOPROTOOPT;
3173
3174         switch (optname) {
3175         case PACKET_ADD_MEMBERSHIP:
3176         case PACKET_DROP_MEMBERSHIP:
3177         {
3178                 struct packet_mreq_max mreq;
3179                 int len = optlen;
3180                 memset(&mreq, 0, sizeof(mreq));
3181                 if (len < sizeof(struct packet_mreq))
3182                         return -EINVAL;
3183                 if (len > sizeof(mreq))
3184                         len = sizeof(mreq);
3185                 if (copy_from_user(&mreq, optval, len))
3186                         return -EFAULT;
3187                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3188                         return -EINVAL;
3189                 if (optname == PACKET_ADD_MEMBERSHIP)
3190                         ret = packet_mc_add(sk, &mreq);
3191                 else
3192                         ret = packet_mc_drop(sk, &mreq);
3193                 return ret;
3194         }
3195
3196         case PACKET_RX_RING:
3197         case PACKET_TX_RING:
3198         {
3199                 union tpacket_req_u req_u;
3200                 int len;
3201
3202                 switch (po->tp_version) {
3203                 case TPACKET_V1:
3204                 case TPACKET_V2:
3205                         len = sizeof(req_u.req);
3206                         break;
3207                 case TPACKET_V3:
3208                 default:
3209                         len = sizeof(req_u.req3);
3210                         break;
3211                 }
3212                 if (optlen < len)
3213                         return -EINVAL;
3214                 if (pkt_sk(sk)->has_vnet_hdr)
3215                         return -EINVAL;
3216                 if (copy_from_user(&req_u.req, optval, len))
3217                         return -EFAULT;
3218                 return packet_set_ring(sk, &req_u, 0,
3219                         optname == PACKET_TX_RING);
3220         }
3221         case PACKET_COPY_THRESH:
3222         {
3223                 int val;
3224
3225                 if (optlen != sizeof(val))
3226                         return -EINVAL;
3227                 if (copy_from_user(&val, optval, sizeof(val)))
3228                         return -EFAULT;
3229
3230                 pkt_sk(sk)->copy_thresh = val;
3231                 return 0;
3232         }
3233         case PACKET_VERSION:
3234         {
3235                 int val;
3236
3237                 if (optlen != sizeof(val))
3238                         return -EINVAL;
3239                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3240                         return -EBUSY;
3241                 if (copy_from_user(&val, optval, sizeof(val)))
3242                         return -EFAULT;
3243                 switch (val) {
3244                 case TPACKET_V1:
3245                 case TPACKET_V2:
3246                 case TPACKET_V3:
3247                         po->tp_version = val;
3248                         return 0;
3249                 default:
3250                         return -EINVAL;
3251                 }
3252         }
3253         case PACKET_RESERVE:
3254         {
3255                 unsigned int val;
3256
3257                 if (optlen != sizeof(val))
3258                         return -EINVAL;
3259                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3260                         return -EBUSY;
3261                 if (copy_from_user(&val, optval, sizeof(val)))
3262                         return -EFAULT;
3263                 po->tp_reserve = val;
3264                 return 0;
3265         }
3266         case PACKET_LOSS:
3267         {
3268                 unsigned int val;
3269
3270                 if (optlen != sizeof(val))
3271                         return -EINVAL;
3272                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3273                         return -EBUSY;
3274                 if (copy_from_user(&val, optval, sizeof(val)))
3275                         return -EFAULT;
3276                 po->tp_loss = !!val;
3277                 return 0;
3278         }
3279         case PACKET_AUXDATA:
3280         {
3281                 int val;
3282
3283                 if (optlen < sizeof(val))
3284                         return -EINVAL;
3285                 if (copy_from_user(&val, optval, sizeof(val)))
3286                         return -EFAULT;
3287
3288                 po->auxdata = !!val;
3289                 return 0;
3290         }
3291         case PACKET_ORIGDEV:
3292         {
3293                 int val;
3294
3295                 if (optlen < sizeof(val))
3296                         return -EINVAL;
3297                 if (copy_from_user(&val, optval, sizeof(val)))
3298                         return -EFAULT;
3299
3300                 po->origdev = !!val;
3301                 return 0;
3302         }
3303         case PACKET_VNET_HDR:
3304         {
3305                 int val;
3306
3307                 if (sock->type != SOCK_RAW)
3308                         return -EINVAL;
3309                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3310                         return -EBUSY;
3311                 if (optlen < sizeof(val))
3312                         return -EINVAL;
3313                 if (copy_from_user(&val, optval, sizeof(val)))
3314                         return -EFAULT;
3315
3316                 po->has_vnet_hdr = !!val;
3317                 return 0;
3318         }
3319         case PACKET_TIMESTAMP:
3320         {
3321                 int val;
3322
3323                 if (optlen != sizeof(val))
3324                         return -EINVAL;
3325                 if (copy_from_user(&val, optval, sizeof(val)))
3326                         return -EFAULT;
3327
3328                 po->tp_tstamp = val;
3329                 return 0;
3330         }
3331         case PACKET_FANOUT:
3332         {
3333                 int val;
3334
3335                 if (optlen != sizeof(val))
3336                         return -EINVAL;
3337                 if (copy_from_user(&val, optval, sizeof(val)))
3338                         return -EFAULT;
3339
3340                 return fanout_add(sk, val & 0xffff, val >> 16);
3341         }
3342         case PACKET_TX_HAS_OFF:
3343         {
3344                 unsigned int val;
3345
3346                 if (optlen != sizeof(val))
3347                         return -EINVAL;
3348                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3349                         return -EBUSY;
3350                 if (copy_from_user(&val, optval, sizeof(val)))
3351                         return -EFAULT;
3352                 po->tp_tx_has_off = !!val;
3353                 return 0;
3354         }
3355         case PACKET_QDISC_BYPASS:
3356         {
3357                 int val;
3358
3359                 if (optlen != sizeof(val))
3360                         return -EINVAL;
3361                 if (copy_from_user(&val, optval, sizeof(val)))
3362                         return -EFAULT;
3363
3364                 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3365                 return 0;
3366         }
3367         default:
3368                 return -ENOPROTOOPT;
3369         }
3370 }
3371
3372 static int packet_getsockopt(struct socket *sock, int level, int optname,
3373                              char __user *optval, int __user *optlen)
3374 {
3375         int len;
3376         int val, lv = sizeof(val);
3377         struct sock *sk = sock->sk;
3378         struct packet_sock *po = pkt_sk(sk);
3379         void *data = &val;
3380         union tpacket_stats_u st;
3381
3382         if (level != SOL_PACKET)
3383                 return -ENOPROTOOPT;
3384
3385         if (get_user(len, optlen))
3386                 return -EFAULT;
3387
3388         if (len < 0)
3389                 return -EINVAL;
3390
3391         switch (optname) {
3392         case PACKET_STATISTICS:
3393                 spin_lock_bh(&sk->sk_receive_queue.lock);
3394                 memcpy(&st, &po->stats, sizeof(st));
3395                 memset(&po->stats, 0, sizeof(po->stats));
3396                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3397
3398                 if (po->tp_version == TPACKET_V3) {
3399                         lv = sizeof(struct tpacket_stats_v3);
3400                         st.stats3.tp_packets += st.stats3.tp_drops;
3401                         data = &st.stats3;
3402                 } else {
3403                         lv = sizeof(struct tpacket_stats);
3404                         st.stats1.tp_packets += st.stats1.tp_drops;
3405                         data = &st.stats1;
3406                 }
3407
3408                 break;
3409         case PACKET_AUXDATA:
3410                 val = po->auxdata;
3411                 break;
3412         case PACKET_ORIGDEV:
3413                 val = po->origdev;
3414                 break;
3415         case PACKET_VNET_HDR:
3416                 val = po->has_vnet_hdr;
3417                 break;
3418         case PACKET_VERSION:
3419                 val = po->tp_version;
3420                 break;
3421         case PACKET_HDRLEN:
3422                 if (len > sizeof(int))
3423                         len = sizeof(int);
3424                 if (copy_from_user(&val, optval, len))
3425                         return -EFAULT;
3426                 switch (val) {
3427                 case TPACKET_V1:
3428                         val = sizeof(struct tpacket_hdr);
3429                         break;
3430                 case TPACKET_V2:
3431                         val = sizeof(struct tpacket2_hdr);
3432                         break;
3433                 case TPACKET_V3:
3434                         val = sizeof(struct tpacket3_hdr);
3435                         break;
3436                 default:
3437                         return -EINVAL;
3438                 }
3439                 break;
3440         case PACKET_RESERVE:
3441                 val = po->tp_reserve;
3442                 break;
3443         case PACKET_LOSS:
3444                 val = po->tp_loss;
3445                 break;
3446         case PACKET_TIMESTAMP:
3447                 val = po->tp_tstamp;
3448                 break;
3449         case PACKET_FANOUT:
3450                 val = (po->fanout ?
3451                        ((u32)po->fanout->id |
3452                         ((u32)po->fanout->type << 16) |
3453                         ((u32)po->fanout->flags << 24)) :
3454                        0);
3455                 break;
3456         case PACKET_TX_HAS_OFF:
3457                 val = po->tp_tx_has_off;
3458                 break;
3459         case PACKET_QDISC_BYPASS:
3460                 val = packet_use_direct_xmit(po);
3461                 break;
3462         default:
3463                 return -ENOPROTOOPT;
3464         }
3465
3466         if (len > lv)
3467                 len = lv;
3468         if (put_user(len, optlen))
3469                 return -EFAULT;
3470         if (copy_to_user(optval, data, len))
3471                 return -EFAULT;
3472         return 0;
3473 }
3474
3475
3476 static int packet_notifier(struct notifier_block *this,
3477                            unsigned long msg, void *ptr)
3478 {
3479         struct sock *sk;
3480         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3481         struct net *net = dev_net(dev);
3482
3483         rcu_read_lock();
3484         sk_for_each_rcu(sk, &net->packet.sklist) {
3485                 struct packet_sock *po = pkt_sk(sk);
3486
3487                 switch (msg) {
3488                 case NETDEV_UNREGISTER:
3489                         if (po->mclist)
3490                                 packet_dev_mclist(dev, po->mclist, -1);
3491                         /* fallthrough */
3492
3493                 case NETDEV_DOWN:
3494                         if (dev->ifindex == po->ifindex) {
3495                                 spin_lock(&po->bind_lock);
3496                                 if (po->running) {
3497                                         __unregister_prot_hook(sk, false);
3498                                         sk->sk_err = ENETDOWN;
3499                                         if (!sock_flag(sk, SOCK_DEAD))
3500                                                 sk->sk_error_report(sk);
3501                                 }
3502                                 if (msg == NETDEV_UNREGISTER) {
3503                                         packet_cached_dev_reset(po);
3504                                         po->ifindex = -1;
3505                                         if (po->prot_hook.dev)
3506                                                 dev_put(po->prot_hook.dev);
3507                                         po->prot_hook.dev = NULL;
3508                                 }
3509                                 spin_unlock(&po->bind_lock);
3510                         }
3511                         break;
3512                 case NETDEV_UP:
3513                         if (dev->ifindex == po->ifindex) {
3514                                 spin_lock(&po->bind_lock);
3515                                 if (po->num)
3516                                         register_prot_hook(sk);
3517                                 spin_unlock(&po->bind_lock);
3518                         }
3519                         break;
3520                 }
3521         }
3522         rcu_read_unlock();
3523         return NOTIFY_DONE;
3524 }
3525
3526
3527 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3528                         unsigned long arg)
3529 {
3530         struct sock *sk = sock->sk;
3531
3532         switch (cmd) {
3533         case SIOCOUTQ:
3534         {
3535                 int amount = sk_wmem_alloc_get(sk);
3536
3537                 return put_user(amount, (int __user *)arg);
3538         }
3539         case SIOCINQ:
3540         {
3541                 struct sk_buff *skb;
3542                 int amount = 0;
3543
3544                 spin_lock_bh(&sk->sk_receive_queue.lock);
3545                 skb = skb_peek(&sk->sk_receive_queue);
3546                 if (skb)
3547                         amount = skb->len;
3548                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3549                 return put_user(amount, (int __user *)arg);
3550         }
3551         case SIOCGSTAMP:
3552                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3553         case SIOCGSTAMPNS:
3554                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3555
3556 #ifdef CONFIG_INET
3557         case SIOCADDRT:
3558         case SIOCDELRT:
3559         case SIOCDARP:
3560         case SIOCGARP:
3561         case SIOCSARP:
3562         case SIOCGIFADDR:
3563         case SIOCSIFADDR:
3564         case SIOCGIFBRDADDR:
3565         case SIOCSIFBRDADDR:
3566         case SIOCGIFNETMASK:
3567         case SIOCSIFNETMASK:
3568         case SIOCGIFDSTADDR:
3569         case SIOCSIFDSTADDR:
3570         case SIOCSIFFLAGS:
3571                 return inet_dgram_ops.ioctl(sock, cmd, arg);
3572 #endif
3573
3574         default:
3575                 return -ENOIOCTLCMD;
3576         }
3577         return 0;
3578 }
3579
3580 static unsigned int packet_poll(struct file *file, struct socket *sock,
3581                                 poll_table *wait)
3582 {
3583         struct sock *sk = sock->sk;
3584         struct packet_sock *po = pkt_sk(sk);
3585         unsigned int mask = datagram_poll(file, sock, wait);
3586
3587         spin_lock_bh(&sk->sk_receive_queue.lock);
3588         if (po->rx_ring.pg_vec) {
3589                 if (!packet_previous_rx_frame(po, &po->rx_ring,
3590                         TP_STATUS_KERNEL))
3591                         mask |= POLLIN | POLLRDNORM;
3592         }
3593         spin_unlock_bh(&sk->sk_receive_queue.lock);
3594         spin_lock_bh(&sk->sk_write_queue.lock);
3595         if (po->tx_ring.pg_vec) {
3596                 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3597                         mask |= POLLOUT | POLLWRNORM;
3598         }
3599         spin_unlock_bh(&sk->sk_write_queue.lock);
3600         return mask;
3601 }
3602
3603
3604 /* Dirty? Well, I still did not learn better way to account
3605  * for user mmaps.
3606  */
3607
3608 static void packet_mm_open(struct vm_area_struct *vma)
3609 {
3610         struct file *file = vma->vm_file;
3611         struct socket *sock = file->private_data;
3612         struct sock *sk = sock->sk;
3613
3614         if (sk)
3615                 atomic_inc(&pkt_sk(sk)->mapped);
3616 }
3617
3618 static void packet_mm_close(struct vm_area_struct *vma)
3619 {
3620         struct file *file = vma->vm_file;
3621         struct socket *sock = file->private_data;
3622         struct sock *sk = sock->sk;
3623
3624         if (sk)
3625                 atomic_dec(&pkt_sk(sk)->mapped);
3626 }
3627
3628 static const struct vm_operations_struct packet_mmap_ops = {
3629         .open   =       packet_mm_open,
3630         .close  =       packet_mm_close,
3631 };
3632
3633 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3634                         unsigned int len)
3635 {
3636         int i;
3637
3638         for (i = 0; i < len; i++) {
3639                 if (likely(pg_vec[i].buffer)) {
3640                         if (is_vmalloc_addr(pg_vec[i].buffer))
3641                                 vfree(pg_vec[i].buffer);
3642                         else
3643                                 free_pages((unsigned long)pg_vec[i].buffer,
3644                                            order);
3645                         pg_vec[i].buffer = NULL;
3646                 }
3647         }
3648         kfree(pg_vec);
3649 }
3650
3651 static char *alloc_one_pg_vec_page(unsigned long order)
3652 {
3653         char *buffer;
3654         gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3655                           __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3656
3657         buffer = (char *) __get_free_pages(gfp_flags, order);
3658         if (buffer)
3659                 return buffer;
3660
3661         /* __get_free_pages failed, fall back to vmalloc */
3662         buffer = vzalloc((1 << order) * PAGE_SIZE);
3663         if (buffer)
3664                 return buffer;
3665
3666         /* vmalloc failed, lets dig into swap here */
3667         gfp_flags &= ~__GFP_NORETRY;
3668         buffer = (char *) __get_free_pages(gfp_flags, order);
3669         if (buffer)
3670                 return buffer;
3671
3672         /* complete and utter failure */
3673         return NULL;
3674 }
3675
3676 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3677 {
3678         unsigned int block_nr = req->tp_block_nr;
3679         struct pgv *pg_vec;
3680         int i;
3681
3682         pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3683         if (unlikely(!pg_vec))
3684                 goto out;
3685
3686         for (i = 0; i < block_nr; i++) {
3687                 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3688                 if (unlikely(!pg_vec[i].buffer))
3689                         goto out_free_pgvec;
3690         }
3691
3692 out:
3693         return pg_vec;
3694
3695 out_free_pgvec:
3696         free_pg_vec(pg_vec, order, block_nr);
3697         pg_vec = NULL;
3698         goto out;
3699 }
3700
3701 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3702                 int closing, int tx_ring)
3703 {
3704         struct pgv *pg_vec = NULL;
3705         struct packet_sock *po = pkt_sk(sk);
3706         int was_running, order = 0;
3707         struct packet_ring_buffer *rb;
3708         struct sk_buff_head *rb_queue;
3709         __be16 num;
3710         int err = -EINVAL;
3711         /* Added to avoid minimal code churn */
3712         struct tpacket_req *req = &req_u->req;
3713
3714         /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3715         if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3716                 WARN(1, "Tx-ring is not supported.\n");
3717                 goto out;
3718         }
3719
3720         rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3721         rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3722
3723         err = -EBUSY;
3724         if (!closing) {
3725                 if (atomic_read(&po->mapped))
3726                         goto out;
3727                 if (packet_read_pending(rb))
3728                         goto out;
3729         }
3730
3731         if (req->tp_block_nr) {
3732                 /* Sanity tests and some calculations */
3733                 err = -EBUSY;
3734                 if (unlikely(rb->pg_vec))
3735                         goto out;
3736
3737                 switch (po->tp_version) {
3738                 case TPACKET_V1:
3739                         po->tp_hdrlen = TPACKET_HDRLEN;
3740                         break;
3741                 case TPACKET_V2:
3742                         po->tp_hdrlen = TPACKET2_HDRLEN;
3743                         break;
3744                 case TPACKET_V3:
3745                         po->tp_hdrlen = TPACKET3_HDRLEN;
3746                         break;
3747                 }
3748
3749                 err = -EINVAL;
3750                 if (unlikely((int)req->tp_block_size <= 0))
3751                         goto out;
3752                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3753                         goto out;
3754                 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3755                                         po->tp_reserve))
3756                         goto out;
3757                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3758                         goto out;
3759
3760                 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3761                 if (unlikely(rb->frames_per_block <= 0))
3762                         goto out;
3763                 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3764                                         req->tp_frame_nr))
3765                         goto out;
3766
3767                 err = -ENOMEM;
3768                 order = get_order(req->tp_block_size);
3769                 pg_vec = alloc_pg_vec(req, order);
3770                 if (unlikely(!pg_vec))
3771                         goto out;
3772                 switch (po->tp_version) {
3773                 case TPACKET_V3:
3774                 /* Transmit path is not supported. We checked
3775                  * it above but just being paranoid
3776                  */
3777                         if (!tx_ring)
3778                                 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3779                                 break;
3780                 default:
3781                         break;
3782                 }
3783         }
3784         /* Done */
3785         else {
3786                 err = -EINVAL;
3787                 if (unlikely(req->tp_frame_nr))
3788                         goto out;
3789         }
3790
3791         lock_sock(sk);
3792
3793         /* Detach socket from network */
3794         spin_lock(&po->bind_lock);
3795         was_running = po->running;
3796         num = po->num;
3797         if (was_running) {
3798                 po->num = 0;
3799                 __unregister_prot_hook(sk, false);
3800         }
3801         spin_unlock(&po->bind_lock);
3802
3803         synchronize_net();
3804
3805         err = -EBUSY;
3806         mutex_lock(&po->pg_vec_lock);
3807         if (closing || atomic_read(&po->mapped) == 0) {
3808                 err = 0;
3809                 spin_lock_bh(&rb_queue->lock);
3810                 swap(rb->pg_vec, pg_vec);
3811                 rb->frame_max = (req->tp_frame_nr - 1);
3812                 rb->head = 0;
3813                 rb->frame_size = req->tp_frame_size;
3814                 spin_unlock_bh(&rb_queue->lock);
3815
3816                 swap(rb->pg_vec_order, order);
3817                 swap(rb->pg_vec_len, req->tp_block_nr);
3818
3819                 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3820                 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3821                                                 tpacket_rcv : packet_rcv;
3822                 skb_queue_purge(rb_queue);
3823                 if (atomic_read(&po->mapped))
3824                         pr_err("packet_mmap: vma is busy: %d\n",
3825                                atomic_read(&po->mapped));
3826         }
3827         mutex_unlock(&po->pg_vec_lock);
3828
3829         spin_lock(&po->bind_lock);
3830         if (was_running) {
3831                 po->num = num;
3832                 register_prot_hook(sk);
3833         }
3834         spin_unlock(&po->bind_lock);
3835         if (closing && (po->tp_version > TPACKET_V2)) {
3836                 /* Because we don't support block-based V3 on tx-ring */
3837                 if (!tx_ring)
3838                         prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3839         }
3840         release_sock(sk);
3841
3842         if (pg_vec)
3843                 free_pg_vec(pg_vec, order, req->tp_block_nr);
3844 out:
3845         return err;
3846 }
3847
3848 static int packet_mmap(struct file *file, struct socket *sock,
3849                 struct vm_area_struct *vma)
3850 {
3851         struct sock *sk = sock->sk;
3852         struct packet_sock *po = pkt_sk(sk);
3853         unsigned long size, expected_size;
3854         struct packet_ring_buffer *rb;
3855         unsigned long start;
3856         int err = -EINVAL;
3857         int i;
3858
3859         if (vma->vm_pgoff)
3860                 return -EINVAL;
3861
3862         mutex_lock(&po->pg_vec_lock);
3863
3864         expected_size = 0;
3865         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3866                 if (rb->pg_vec) {
3867                         expected_size += rb->pg_vec_len
3868                                                 * rb->pg_vec_pages
3869                                                 * PAGE_SIZE;
3870                 }
3871         }
3872
3873         if (expected_size == 0)
3874                 goto out;
3875
3876         size = vma->vm_end - vma->vm_start;
3877         if (size != expected_size)
3878                 goto out;
3879
3880         start = vma->vm_start;
3881         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3882                 if (rb->pg_vec == NULL)
3883                         continue;
3884
3885                 for (i = 0; i < rb->pg_vec_len; i++) {
3886                         struct page *page;
3887                         void *kaddr = rb->pg_vec[i].buffer;
3888                         int pg_num;
3889
3890                         for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3891                                 page = pgv_to_page(kaddr);
3892                                 err = vm_insert_page(vma, start, page);
3893                                 if (unlikely(err))
3894                                         goto out;
3895                                 start += PAGE_SIZE;
3896                                 kaddr += PAGE_SIZE;
3897                         }
3898                 }
3899         }
3900
3901         atomic_inc(&po->mapped);
3902         vma->vm_ops = &packet_mmap_ops;
3903         err = 0;
3904
3905 out:
3906         mutex_unlock(&po->pg_vec_lock);
3907         return err;
3908 }
3909
3910 static const struct proto_ops packet_ops_spkt = {
3911         .family =       PF_PACKET,
3912         .owner =        THIS_MODULE,
3913         .release =      packet_release,
3914         .bind =         packet_bind_spkt,
3915         .connect =      sock_no_connect,
3916         .socketpair =   sock_no_socketpair,
3917         .accept =       sock_no_accept,
3918         .getname =      packet_getname_spkt,
3919         .poll =         datagram_poll,
3920         .ioctl =        packet_ioctl,
3921         .listen =       sock_no_listen,
3922         .shutdown =     sock_no_shutdown,
3923         .setsockopt =   sock_no_setsockopt,
3924         .getsockopt =   sock_no_getsockopt,
3925         .sendmsg =      packet_sendmsg_spkt,
3926         .recvmsg =      packet_recvmsg,
3927         .mmap =         sock_no_mmap,
3928         .sendpage =     sock_no_sendpage,
3929 };
3930
3931 static const struct proto_ops packet_ops = {
3932         .family =       PF_PACKET,
3933         .owner =        THIS_MODULE,
3934         .release =      packet_release,
3935         .bind =         packet_bind,
3936         .connect =      sock_no_connect,
3937         .socketpair =   sock_no_socketpair,
3938         .accept =       sock_no_accept,
3939         .getname =      packet_getname,
3940         .poll =         packet_poll,
3941         .ioctl =        packet_ioctl,
3942         .listen =       sock_no_listen,
3943         .shutdown =     sock_no_shutdown,
3944         .setsockopt =   packet_setsockopt,
3945         .getsockopt =   packet_getsockopt,
3946         .sendmsg =      packet_sendmsg,
3947         .recvmsg =      packet_recvmsg,
3948         .mmap =         packet_mmap,
3949         .sendpage =     sock_no_sendpage,
3950 };
3951
3952 static const struct net_proto_family packet_family_ops = {
3953         .family =       PF_PACKET,
3954         .create =       packet_create,
3955         .owner  =       THIS_MODULE,
3956 };
3957
3958 static struct notifier_block packet_netdev_notifier = {
3959         .notifier_call =        packet_notifier,
3960 };
3961
3962 #ifdef CONFIG_PROC_FS
3963
3964 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3965         __acquires(RCU)
3966 {
3967         struct net *net = seq_file_net(seq);
3968
3969         rcu_read_lock();
3970         return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3971 }
3972
3973 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3974 {
3975         struct net *net = seq_file_net(seq);
3976         return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3977 }
3978
3979 static void packet_seq_stop(struct seq_file *seq, void *v)
3980         __releases(RCU)
3981 {
3982         rcu_read_unlock();
3983 }
3984
3985 static int packet_seq_show(struct seq_file *seq, void *v)
3986 {
3987         if (v == SEQ_START_TOKEN)
3988                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
3989         else {
3990                 struct sock *s = sk_entry(v);
3991                 const struct packet_sock *po = pkt_sk(s);
3992
3993                 seq_printf(seq,
3994                            "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
3995                            s,
3996                            atomic_read(&s->sk_refcnt),
3997                            s->sk_type,
3998                            ntohs(po->num),
3999                            po->ifindex,
4000                            po->running,
4001                            atomic_read(&s->sk_rmem_alloc),
4002                            from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4003                            sock_i_ino(s));
4004         }
4005
4006         return 0;
4007 }
4008
4009 static const struct seq_operations packet_seq_ops = {
4010         .start  = packet_seq_start,
4011         .next   = packet_seq_next,
4012         .stop   = packet_seq_stop,
4013         .show   = packet_seq_show,
4014 };
4015
4016 static int packet_seq_open(struct inode *inode, struct file *file)
4017 {
4018         return seq_open_net(inode, file, &packet_seq_ops,
4019                             sizeof(struct seq_net_private));
4020 }
4021
4022 static const struct file_operations packet_seq_fops = {
4023         .owner          = THIS_MODULE,
4024         .open           = packet_seq_open,
4025         .read           = seq_read,
4026         .llseek         = seq_lseek,
4027         .release        = seq_release_net,
4028 };
4029
4030 #endif
4031
4032 static int __net_init packet_net_init(struct net *net)
4033 {
4034         mutex_init(&net->packet.sklist_lock);
4035         INIT_HLIST_HEAD(&net->packet.sklist);
4036
4037         if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4038                 return -ENOMEM;
4039
4040         return 0;
4041 }
4042
4043 static void __net_exit packet_net_exit(struct net *net)
4044 {
4045         remove_proc_entry("packet", net->proc_net);
4046 }
4047
4048 static struct pernet_operations packet_net_ops = {
4049         .init = packet_net_init,
4050         .exit = packet_net_exit,
4051 };
4052
4053
4054 static void __exit packet_exit(void)
4055 {
4056         unregister_netdevice_notifier(&packet_netdev_notifier);
4057         unregister_pernet_subsys(&packet_net_ops);
4058         sock_unregister(PF_PACKET);
4059         proto_unregister(&packet_proto);
4060 }
4061
4062 static int __init packet_init(void)
4063 {
4064         int rc = proto_register(&packet_proto, 0);
4065
4066         if (rc != 0)
4067                 goto out;
4068
4069         sock_register(&packet_family_ops);
4070         register_pernet_subsys(&packet_net_ops);
4071         register_netdevice_notifier(&packet_netdev_notifier);
4072 out:
4073         return rc;
4074 }
4075
4076 module_init(packet_init);
4077 module_exit(packet_exit);
4078 MODULE_LICENSE("GPL");
4079 MODULE_ALIAS_NETPROTO(PF_PACKET);