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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/percpu.h>
92#ifdef CONFIG_INET
93#include <net/inet_common.h>
94#endif
95#include <linux/bpf.h>
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
110On receive:
111-----------
112
113Incoming, dev->hard_header!=NULL
114 mac_header -> ll header
115 data -> data
116
117Outgoing, dev->hard_header!=NULL
118 mac_header -> ll header
119 data -> ll header
120
121Incoming, 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
127Outgoing, dev->hard_header==NULL
128 mac_header -> data. ll header is still not built!
129 data -> data
130
131Resume
132 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
133
134
135On transmit:
136------------
137
138dev->hard_header != NULL
139 mac_header -> ll header
140 data -> ll header
141
142dev->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 */
155struct 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
162union tpacket_uhdr {
163 struct tpacket_hdr *h1;
164 struct tpacket2_hdr *h2;
165 struct tpacket3_hdr *h3;
166 void *raw;
167};
168
169static 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
189struct packet_sock;
190static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
191static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
192 struct packet_type *pt, struct net_device *orig_dev);
193
194static void *packet_previous_frame(struct packet_sock *po,
195 struct packet_ring_buffer *rb,
196 int status);
197static void packet_increment_head(struct packet_ring_buffer *buff);
198static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
199 struct tpacket_block_desc *);
200static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
201 struct packet_sock *);
202static void prb_retire_current_block(struct tpacket_kbdq_core *,
203 struct packet_sock *, unsigned int status);
204static int prb_queue_frozen(struct tpacket_kbdq_core *);
205static void prb_open_block(struct tpacket_kbdq_core *,
206 struct tpacket_block_desc *);
207static void prb_retire_rx_blk_timer_expired(unsigned long);
208static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
209static void prb_init_blk_timer(struct packet_sock *,
210 struct tpacket_kbdq_core *,
211 void (*func) (unsigned long));
212static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
213static void prb_clear_rxhash(struct tpacket_kbdq_core *,
214 struct tpacket3_hdr *);
215static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
216 struct tpacket3_hdr *);
217static void packet_flush_mclist(struct sock *sk);
218
219struct packet_skb_cb {
220 union {
221 struct sockaddr_pkt pkt;
222 union {
223 /* Trick: alias skb original length with
224 * ll.sll_family and ll.protocol in order
225 * to save room.
226 */
227 unsigned int origlen;
228 struct sockaddr_ll ll;
229 };
230 } sa;
231};
232
233#define vio_le() virtio_legacy_is_little_endian()
234
235#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
236
237#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
238#define GET_PBLOCK_DESC(x, bid) \
239 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
240#define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
241 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
242#define GET_NEXT_PRB_BLK_NUM(x) \
243 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
244 ((x)->kactive_blk_num+1) : 0)
245
246static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
247static void __fanout_link(struct sock *sk, struct packet_sock *po);
248
249static int packet_direct_xmit(struct sk_buff *skb)
250{
251 struct net_device *dev = skb->dev;
252 netdev_features_t features;
253 struct netdev_queue *txq;
254 int ret = NETDEV_TX_BUSY;
255
256 if (unlikely(!netif_running(dev) ||
257 !netif_carrier_ok(dev)))
258 goto drop;
259
260 features = netif_skb_features(skb);
261 if (skb_needs_linearize(skb, features) &&
262 __skb_linearize(skb))
263 goto drop;
264
265 txq = skb_get_tx_queue(dev, skb);
266
267 local_bh_disable();
268
269 HARD_TX_LOCK(dev, txq, smp_processor_id());
270 if (!netif_xmit_frozen_or_drv_stopped(txq))
271 ret = netdev_start_xmit(skb, dev, txq, false);
272 HARD_TX_UNLOCK(dev, txq);
273
274 local_bh_enable();
275
276 if (!dev_xmit_complete(ret))
277 kfree_skb(skb);
278
279 return ret;
280drop:
281 atomic_long_inc(&dev->tx_dropped);
282 kfree_skb(skb);
283 return NET_XMIT_DROP;
284}
285
286static struct net_device *packet_cached_dev_get(struct packet_sock *po)
287{
288 struct net_device *dev;
289
290 rcu_read_lock();
291 dev = rcu_dereference(po->cached_dev);
292 if (likely(dev))
293 dev_hold(dev);
294 rcu_read_unlock();
295
296 return dev;
297}
298
299static void packet_cached_dev_assign(struct packet_sock *po,
300 struct net_device *dev)
301{
302 rcu_assign_pointer(po->cached_dev, dev);
303}
304
305static void packet_cached_dev_reset(struct packet_sock *po)
306{
307 RCU_INIT_POINTER(po->cached_dev, NULL);
308}
309
310static bool packet_use_direct_xmit(const struct packet_sock *po)
311{
312 return po->xmit == packet_direct_xmit;
313}
314
315static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
316{
317 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
318}
319
320static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
321{
322 const struct net_device_ops *ops = dev->netdev_ops;
323 u16 queue_index;
324
325 if (ops->ndo_select_queue) {
326 queue_index = ops->ndo_select_queue(dev, skb, NULL,
327 __packet_pick_tx_queue);
328 queue_index = netdev_cap_txqueue(dev, queue_index);
329 } else {
330 queue_index = __packet_pick_tx_queue(dev, skb);
331 }
332
333 skb_set_queue_mapping(skb, queue_index);
334}
335
336/* register_prot_hook must be invoked with the po->bind_lock held,
337 * or from a context in which asynchronous accesses to the packet
338 * socket is not possible (packet_create()).
339 */
340static void register_prot_hook(struct sock *sk)
341{
342 struct packet_sock *po = pkt_sk(sk);
343
344 if (!po->running) {
345 if (po->fanout)
346 __fanout_link(sk, po);
347 else
348 dev_add_pack(&po->prot_hook);
349
350 sock_hold(sk);
351 po->running = 1;
352 }
353}
354
355/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
356 * held. If the sync parameter is true, we will temporarily drop
357 * the po->bind_lock and do a synchronize_net to make sure no
358 * asynchronous packet processing paths still refer to the elements
359 * of po->prot_hook. If the sync parameter is false, it is the
360 * callers responsibility to take care of this.
361 */
362static void __unregister_prot_hook(struct sock *sk, bool sync)
363{
364 struct packet_sock *po = pkt_sk(sk);
365
366 po->running = 0;
367
368 if (po->fanout)
369 __fanout_unlink(sk, po);
370 else
371 __dev_remove_pack(&po->prot_hook);
372
373 __sock_put(sk);
374
375 if (sync) {
376 spin_unlock(&po->bind_lock);
377 synchronize_net();
378 spin_lock(&po->bind_lock);
379 }
380}
381
382static void unregister_prot_hook(struct sock *sk, bool sync)
383{
384 struct packet_sock *po = pkt_sk(sk);
385
386 if (po->running)
387 __unregister_prot_hook(sk, sync);
388}
389
390static inline struct page * __pure pgv_to_page(void *addr)
391{
392 if (is_vmalloc_addr(addr))
393 return vmalloc_to_page(addr);
394 return virt_to_page(addr);
395}
396
397static void __packet_set_status(struct packet_sock *po, void *frame, int status)
398{
399 union tpacket_uhdr h;
400
401 h.raw = frame;
402 switch (po->tp_version) {
403 case TPACKET_V1:
404 h.h1->tp_status = status;
405 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
406 break;
407 case TPACKET_V2:
408 h.h2->tp_status = status;
409 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
410 break;
411 case TPACKET_V3:
412 default:
413 WARN(1, "TPACKET version not supported.\n");
414 BUG();
415 }
416
417 smp_wmb();
418}
419
420static int __packet_get_status(struct packet_sock *po, void *frame)
421{
422 union tpacket_uhdr h;
423
424 smp_rmb();
425
426 h.raw = frame;
427 switch (po->tp_version) {
428 case TPACKET_V1:
429 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
430 return h.h1->tp_status;
431 case TPACKET_V2:
432 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
433 return h.h2->tp_status;
434 case TPACKET_V3:
435 default:
436 WARN(1, "TPACKET version not supported.\n");
437 BUG();
438 return 0;
439 }
440}
441
442static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
443 unsigned int flags)
444{
445 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
446
447 if (shhwtstamps &&
448 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
449 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
450 return TP_STATUS_TS_RAW_HARDWARE;
451
452 if (ktime_to_timespec_cond(skb->tstamp, ts))
453 return TP_STATUS_TS_SOFTWARE;
454
455 return 0;
456}
457
458static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
459 struct sk_buff *skb)
460{
461 union tpacket_uhdr h;
462 struct timespec ts;
463 __u32 ts_status;
464
465 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
466 return 0;
467
468 h.raw = frame;
469 switch (po->tp_version) {
470 case TPACKET_V1:
471 h.h1->tp_sec = ts.tv_sec;
472 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
473 break;
474 case TPACKET_V2:
475 h.h2->tp_sec = ts.tv_sec;
476 h.h2->tp_nsec = ts.tv_nsec;
477 break;
478 case TPACKET_V3:
479 default:
480 WARN(1, "TPACKET version not supported.\n");
481 BUG();
482 }
483
484 /* one flush is safe, as both fields always lie on the same cacheline */
485 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
486 smp_wmb();
487
488 return ts_status;
489}
490
491static void *packet_lookup_frame(struct packet_sock *po,
492 struct packet_ring_buffer *rb,
493 unsigned int position,
494 int status)
495{
496 unsigned int pg_vec_pos, frame_offset;
497 union tpacket_uhdr h;
498
499 pg_vec_pos = position / rb->frames_per_block;
500 frame_offset = position % rb->frames_per_block;
501
502 h.raw = rb->pg_vec[pg_vec_pos].buffer +
503 (frame_offset * rb->frame_size);
504
505 if (status != __packet_get_status(po, h.raw))
506 return NULL;
507
508 return h.raw;
509}
510
511static void *packet_current_frame(struct packet_sock *po,
512 struct packet_ring_buffer *rb,
513 int status)
514{
515 return packet_lookup_frame(po, rb, rb->head, status);
516}
517
518static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
519{
520 del_timer_sync(&pkc->retire_blk_timer);
521}
522
523static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
524 struct sk_buff_head *rb_queue)
525{
526 struct tpacket_kbdq_core *pkc;
527
528 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
529
530 spin_lock_bh(&rb_queue->lock);
531 pkc->delete_blk_timer = 1;
532 spin_unlock_bh(&rb_queue->lock);
533
534 prb_del_retire_blk_timer(pkc);
535}
536
537static void prb_init_blk_timer(struct packet_sock *po,
538 struct tpacket_kbdq_core *pkc,
539 void (*func) (unsigned long))
540{
541 init_timer(&pkc->retire_blk_timer);
542 pkc->retire_blk_timer.data = (long)po;
543 pkc->retire_blk_timer.function = func;
544 pkc->retire_blk_timer.expires = jiffies;
545}
546
547static void prb_setup_retire_blk_timer(struct packet_sock *po)
548{
549 struct tpacket_kbdq_core *pkc;
550
551 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
552 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
553}
554
555static int prb_calc_retire_blk_tmo(struct packet_sock *po,
556 int blk_size_in_bytes)
557{
558 struct net_device *dev;
559 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
560 struct ethtool_link_ksettings ecmd;
561 int err;
562
563 rtnl_lock();
564 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
565 if (unlikely(!dev)) {
566 rtnl_unlock();
567 return DEFAULT_PRB_RETIRE_TOV;
568 }
569 err = __ethtool_get_link_ksettings(dev, &ecmd);
570 rtnl_unlock();
571 if (!err) {
572 /*
573 * If the link speed is so slow you don't really
574 * need to worry about perf anyways
575 */
576 if (ecmd.base.speed < SPEED_1000 ||
577 ecmd.base.speed == SPEED_UNKNOWN) {
578 return DEFAULT_PRB_RETIRE_TOV;
579 } else {
580 msec = 1;
581 div = ecmd.base.speed / 1000;
582 }
583 }
584
585 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
586
587 if (div)
588 mbits /= div;
589
590 tmo = mbits * msec;
591
592 if (div)
593 return tmo+1;
594 return tmo;
595}
596
597static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
598 union tpacket_req_u *req_u)
599{
600 p1->feature_req_word = req_u->req3.tp_feature_req_word;
601}
602
603static void init_prb_bdqc(struct packet_sock *po,
604 struct packet_ring_buffer *rb,
605 struct pgv *pg_vec,
606 union tpacket_req_u *req_u)
607{
608 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
609 struct tpacket_block_desc *pbd;
610
611 memset(p1, 0x0, sizeof(*p1));
612
613 p1->knxt_seq_num = 1;
614 p1->pkbdq = pg_vec;
615 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
616 p1->pkblk_start = pg_vec[0].buffer;
617 p1->kblk_size = req_u->req3.tp_block_size;
618 p1->knum_blocks = req_u->req3.tp_block_nr;
619 p1->hdrlen = po->tp_hdrlen;
620 p1->version = po->tp_version;
621 p1->last_kactive_blk_num = 0;
622 po->stats.stats3.tp_freeze_q_cnt = 0;
623 if (req_u->req3.tp_retire_blk_tov)
624 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
625 else
626 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
627 req_u->req3.tp_block_size);
628 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
629 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
630
631 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
632 prb_init_ft_ops(p1, req_u);
633 prb_setup_retire_blk_timer(po);
634 prb_open_block(p1, pbd);
635}
636
637/* Do NOT update the last_blk_num first.
638 * Assumes sk_buff_head lock is held.
639 */
640static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
641{
642 mod_timer(&pkc->retire_blk_timer,
643 jiffies + pkc->tov_in_jiffies);
644 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
645}
646
647/*
648 * Timer logic:
649 * 1) We refresh the timer only when we open a block.
650 * By doing this we don't waste cycles refreshing the timer
651 * on packet-by-packet basis.
652 *
653 * With a 1MB block-size, on a 1Gbps line, it will take
654 * i) ~8 ms to fill a block + ii) memcpy etc.
655 * In this cut we are not accounting for the memcpy time.
656 *
657 * So, if the user sets the 'tmo' to 10ms then the timer
658 * will never fire while the block is still getting filled
659 * (which is what we want). However, the user could choose
660 * to close a block early and that's fine.
661 *
662 * But when the timer does fire, we check whether or not to refresh it.
663 * Since the tmo granularity is in msecs, it is not too expensive
664 * to refresh the timer, lets say every '8' msecs.
665 * Either the user can set the 'tmo' or we can derive it based on
666 * a) line-speed and b) block-size.
667 * prb_calc_retire_blk_tmo() calculates the tmo.
668 *
669 */
670static void prb_retire_rx_blk_timer_expired(unsigned long data)
671{
672 struct packet_sock *po = (struct packet_sock *)data;
673 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
674 unsigned int frozen;
675 struct tpacket_block_desc *pbd;
676
677 spin_lock(&po->sk.sk_receive_queue.lock);
678
679 frozen = prb_queue_frozen(pkc);
680 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
681
682 if (unlikely(pkc->delete_blk_timer))
683 goto out;
684
685 /* We only need to plug the race when the block is partially filled.
686 * tpacket_rcv:
687 * lock(); increment BLOCK_NUM_PKTS; unlock()
688 * copy_bits() is in progress ...
689 * timer fires on other cpu:
690 * we can't retire the current block because copy_bits
691 * is in progress.
692 *
693 */
694 if (BLOCK_NUM_PKTS(pbd)) {
695 while (atomic_read(&pkc->blk_fill_in_prog)) {
696 /* Waiting for skb_copy_bits to finish... */
697 cpu_relax();
698 }
699 }
700
701 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
702 if (!frozen) {
703 if (!BLOCK_NUM_PKTS(pbd)) {
704 /* An empty block. Just refresh the timer. */
705 goto refresh_timer;
706 }
707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
708 if (!prb_dispatch_next_block(pkc, po))
709 goto refresh_timer;
710 else
711 goto out;
712 } else {
713 /* Case 1. Queue was frozen because user-space was
714 * lagging behind.
715 */
716 if (prb_curr_blk_in_use(pkc, pbd)) {
717 /*
718 * Ok, user-space is still behind.
719 * So just refresh the timer.
720 */
721 goto refresh_timer;
722 } else {
723 /* Case 2. queue was frozen,user-space caught up,
724 * now the link went idle && the timer fired.
725 * We don't have a block to close.So we open this
726 * block and restart the timer.
727 * opening a block thaws the queue,restarts timer
728 * Thawing/timer-refresh is a side effect.
729 */
730 prb_open_block(pkc, pbd);
731 goto out;
732 }
733 }
734 }
735
736refresh_timer:
737 _prb_refresh_rx_retire_blk_timer(pkc);
738
739out:
740 spin_unlock(&po->sk.sk_receive_queue.lock);
741}
742
743static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
744 struct tpacket_block_desc *pbd1, __u32 status)
745{
746 /* Flush everything minus the block header */
747
748#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
749 u8 *start, *end;
750
751 start = (u8 *)pbd1;
752
753 /* Skip the block header(we know header WILL fit in 4K) */
754 start += PAGE_SIZE;
755
756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
757 for (; start < end; start += PAGE_SIZE)
758 flush_dcache_page(pgv_to_page(start));
759
760 smp_wmb();
761#endif
762
763 /* Now update the block status. */
764
765 BLOCK_STATUS(pbd1) = status;
766
767 /* Flush the block header */
768
769#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
770 start = (u8 *)pbd1;
771 flush_dcache_page(pgv_to_page(start));
772
773 smp_wmb();
774#endif
775}
776
777/*
778 * Side effect:
779 *
780 * 1) flush the block
781 * 2) Increment active_blk_num
782 *
783 * Note:We DONT refresh the timer on purpose.
784 * Because almost always the next block will be opened.
785 */
786static void prb_close_block(struct tpacket_kbdq_core *pkc1,
787 struct tpacket_block_desc *pbd1,
788 struct packet_sock *po, unsigned int stat)
789{
790 __u32 status = TP_STATUS_USER | stat;
791
792 struct tpacket3_hdr *last_pkt;
793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
794 struct sock *sk = &po->sk;
795
796 if (po->stats.stats3.tp_drops)
797 status |= TP_STATUS_LOSING;
798
799 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
800 last_pkt->tp_next_offset = 0;
801
802 /* Get the ts of the last pkt */
803 if (BLOCK_NUM_PKTS(pbd1)) {
804 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
805 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
806 } else {
807 /* Ok, we tmo'd - so get the current time.
808 *
809 * It shouldn't really happen as we don't close empty
810 * blocks. See prb_retire_rx_blk_timer_expired().
811 */
812 struct timespec ts;
813 getnstimeofday(&ts);
814 h1->ts_last_pkt.ts_sec = ts.tv_sec;
815 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
816 }
817
818 smp_wmb();
819
820 /* Flush the block */
821 prb_flush_block(pkc1, pbd1, status);
822
823 sk->sk_data_ready(sk);
824
825 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
826}
827
828static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
829{
830 pkc->reset_pending_on_curr_blk = 0;
831}
832
833/*
834 * Side effect of opening a block:
835 *
836 * 1) prb_queue is thawed.
837 * 2) retire_blk_timer is refreshed.
838 *
839 */
840static void prb_open_block(struct tpacket_kbdq_core *pkc1,
841 struct tpacket_block_desc *pbd1)
842{
843 struct timespec ts;
844 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
845
846 smp_rmb();
847
848 /* We could have just memset this but we will lose the
849 * flexibility of making the priv area sticky
850 */
851
852 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
853 BLOCK_NUM_PKTS(pbd1) = 0;
854 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
855
856 getnstimeofday(&ts);
857
858 h1->ts_first_pkt.ts_sec = ts.tv_sec;
859 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
860
861 pkc1->pkblk_start = (char *)pbd1;
862 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
863
864 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
865 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
866
867 pbd1->version = pkc1->version;
868 pkc1->prev = pkc1->nxt_offset;
869 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
870
871 prb_thaw_queue(pkc1);
872 _prb_refresh_rx_retire_blk_timer(pkc1);
873
874 smp_wmb();
875}
876
877/*
878 * Queue freeze logic:
879 * 1) Assume tp_block_nr = 8 blocks.
880 * 2) At time 't0', user opens Rx ring.
881 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
882 * 4) user-space is either sleeping or processing block '0'.
883 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
884 * it will close block-7,loop around and try to fill block '0'.
885 * call-flow:
886 * __packet_lookup_frame_in_block
887 * prb_retire_current_block()
888 * prb_dispatch_next_block()
889 * |->(BLOCK_STATUS == USER) evaluates to true
890 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
891 * 6) Now there are two cases:
892 * 6.1) Link goes idle right after the queue is frozen.
893 * But remember, the last open_block() refreshed the timer.
894 * When this timer expires,it will refresh itself so that we can
895 * re-open block-0 in near future.
896 * 6.2) Link is busy and keeps on receiving packets. This is a simple
897 * case and __packet_lookup_frame_in_block will check if block-0
898 * is free and can now be re-used.
899 */
900static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
901 struct packet_sock *po)
902{
903 pkc->reset_pending_on_curr_blk = 1;
904 po->stats.stats3.tp_freeze_q_cnt++;
905}
906
907#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
908
909/*
910 * If the next block is free then we will dispatch it
911 * and return a good offset.
912 * Else, we will freeze the queue.
913 * So, caller must check the return value.
914 */
915static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
916 struct packet_sock *po)
917{
918 struct tpacket_block_desc *pbd;
919
920 smp_rmb();
921
922 /* 1. Get current block num */
923 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
924
925 /* 2. If this block is currently in_use then freeze the queue */
926 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
927 prb_freeze_queue(pkc, po);
928 return NULL;
929 }
930
931 /*
932 * 3.
933 * open this block and return the offset where the first packet
934 * needs to get stored.
935 */
936 prb_open_block(pkc, pbd);
937 return (void *)pkc->nxt_offset;
938}
939
940static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
941 struct packet_sock *po, unsigned int status)
942{
943 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
944
945 /* retire/close the current block */
946 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
947 /*
948 * Plug the case where copy_bits() is in progress on
949 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
950 * have space to copy the pkt in the current block and
951 * called prb_retire_current_block()
952 *
953 * We don't need to worry about the TMO case because
954 * the timer-handler already handled this case.
955 */
956 if (!(status & TP_STATUS_BLK_TMO)) {
957 while (atomic_read(&pkc->blk_fill_in_prog)) {
958 /* Waiting for skb_copy_bits to finish... */
959 cpu_relax();
960 }
961 }
962 prb_close_block(pkc, pbd, po, status);
963 return;
964 }
965}
966
967static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
968 struct tpacket_block_desc *pbd)
969{
970 return TP_STATUS_USER & BLOCK_STATUS(pbd);
971}
972
973static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
974{
975 return pkc->reset_pending_on_curr_blk;
976}
977
978static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
979{
980 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
981 atomic_dec(&pkc->blk_fill_in_prog);
982}
983
984static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
985 struct tpacket3_hdr *ppd)
986{
987 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
988}
989
990static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
991 struct tpacket3_hdr *ppd)
992{
993 ppd->hv1.tp_rxhash = 0;
994}
995
996static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
997 struct tpacket3_hdr *ppd)
998{
999 if (skb_vlan_tag_present(pkc->skb)) {
1000 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1001 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1002 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1003 } else {
1004 ppd->hv1.tp_vlan_tci = 0;
1005 ppd->hv1.tp_vlan_tpid = 0;
1006 ppd->tp_status = TP_STATUS_AVAILABLE;
1007 }
1008}
1009
1010static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1011 struct tpacket3_hdr *ppd)
1012{
1013 ppd->hv1.tp_padding = 0;
1014 prb_fill_vlan_info(pkc, ppd);
1015
1016 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1017 prb_fill_rxhash(pkc, ppd);
1018 else
1019 prb_clear_rxhash(pkc, ppd);
1020}
1021
1022static void prb_fill_curr_block(char *curr,
1023 struct tpacket_kbdq_core *pkc,
1024 struct tpacket_block_desc *pbd,
1025 unsigned int len)
1026{
1027 struct tpacket3_hdr *ppd;
1028
1029 ppd = (struct tpacket3_hdr *)curr;
1030 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1031 pkc->prev = curr;
1032 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1033 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1034 BLOCK_NUM_PKTS(pbd) += 1;
1035 atomic_inc(&pkc->blk_fill_in_prog);
1036 prb_run_all_ft_ops(pkc, ppd);
1037}
1038
1039/* Assumes caller has the sk->rx_queue.lock */
1040static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1041 struct sk_buff *skb,
1042 int status,
1043 unsigned int len
1044 )
1045{
1046 struct tpacket_kbdq_core *pkc;
1047 struct tpacket_block_desc *pbd;
1048 char *curr, *end;
1049
1050 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1051 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1052
1053 /* Queue is frozen when user space is lagging behind */
1054 if (prb_queue_frozen(pkc)) {
1055 /*
1056 * Check if that last block which caused the queue to freeze,
1057 * is still in_use by user-space.
1058 */
1059 if (prb_curr_blk_in_use(pkc, pbd)) {
1060 /* Can't record this packet */
1061 return NULL;
1062 } else {
1063 /*
1064 * Ok, the block was released by user-space.
1065 * Now let's open that block.
1066 * opening a block also thaws the queue.
1067 * Thawing is a side effect.
1068 */
1069 prb_open_block(pkc, pbd);
1070 }
1071 }
1072
1073 smp_mb();
1074 curr = pkc->nxt_offset;
1075 pkc->skb = skb;
1076 end = (char *)pbd + pkc->kblk_size;
1077
1078 /* first try the current block */
1079 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1080 prb_fill_curr_block(curr, pkc, pbd, len);
1081 return (void *)curr;
1082 }
1083
1084 /* Ok, close the current block */
1085 prb_retire_current_block(pkc, po, 0);
1086
1087 /* Now, try to dispatch the next block */
1088 curr = (char *)prb_dispatch_next_block(pkc, po);
1089 if (curr) {
1090 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1091 prb_fill_curr_block(curr, pkc, pbd, len);
1092 return (void *)curr;
1093 }
1094
1095 /*
1096 * No free blocks are available.user_space hasn't caught up yet.
1097 * Queue was just frozen and now this packet will get dropped.
1098 */
1099 return NULL;
1100}
1101
1102static void *packet_current_rx_frame(struct packet_sock *po,
1103 struct sk_buff *skb,
1104 int status, unsigned int len)
1105{
1106 char *curr = NULL;
1107 switch (po->tp_version) {
1108 case TPACKET_V1:
1109 case TPACKET_V2:
1110 curr = packet_lookup_frame(po, &po->rx_ring,
1111 po->rx_ring.head, status);
1112 return curr;
1113 case TPACKET_V3:
1114 return __packet_lookup_frame_in_block(po, skb, status, len);
1115 default:
1116 WARN(1, "TPACKET version not supported\n");
1117 BUG();
1118 return NULL;
1119 }
1120}
1121
1122static void *prb_lookup_block(struct packet_sock *po,
1123 struct packet_ring_buffer *rb,
1124 unsigned int idx,
1125 int status)
1126{
1127 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1128 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1129
1130 if (status != BLOCK_STATUS(pbd))
1131 return NULL;
1132 return pbd;
1133}
1134
1135static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1136{
1137 unsigned int prev;
1138 if (rb->prb_bdqc.kactive_blk_num)
1139 prev = rb->prb_bdqc.kactive_blk_num-1;
1140 else
1141 prev = rb->prb_bdqc.knum_blocks-1;
1142 return prev;
1143}
1144
1145/* Assumes caller has held the rx_queue.lock */
1146static void *__prb_previous_block(struct packet_sock *po,
1147 struct packet_ring_buffer *rb,
1148 int status)
1149{
1150 unsigned int previous = prb_previous_blk_num(rb);
1151 return prb_lookup_block(po, rb, previous, status);
1152}
1153
1154static void *packet_previous_rx_frame(struct packet_sock *po,
1155 struct packet_ring_buffer *rb,
1156 int status)
1157{
1158 if (po->tp_version <= TPACKET_V2)
1159 return packet_previous_frame(po, rb, status);
1160
1161 return __prb_previous_block(po, rb, status);
1162}
1163
1164static void packet_increment_rx_head(struct packet_sock *po,
1165 struct packet_ring_buffer *rb)
1166{
1167 switch (po->tp_version) {
1168 case TPACKET_V1:
1169 case TPACKET_V2:
1170 return packet_increment_head(rb);
1171 case TPACKET_V3:
1172 default:
1173 WARN(1, "TPACKET version not supported.\n");
1174 BUG();
1175 return;
1176 }
1177}
1178
1179static void *packet_previous_frame(struct packet_sock *po,
1180 struct packet_ring_buffer *rb,
1181 int status)
1182{
1183 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1184 return packet_lookup_frame(po, rb, previous, status);
1185}
1186
1187static void packet_increment_head(struct packet_ring_buffer *buff)
1188{
1189 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1190}
1191
1192static void packet_inc_pending(struct packet_ring_buffer *rb)
1193{
1194 this_cpu_inc(*rb->pending_refcnt);
1195}
1196
1197static void packet_dec_pending(struct packet_ring_buffer *rb)
1198{
1199 this_cpu_dec(*rb->pending_refcnt);
1200}
1201
1202static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1203{
1204 unsigned int refcnt = 0;
1205 int cpu;
1206
1207 /* We don't use pending refcount in rx_ring. */
1208 if (rb->pending_refcnt == NULL)
1209 return 0;
1210
1211 for_each_possible_cpu(cpu)
1212 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1213
1214 return refcnt;
1215}
1216
1217static int packet_alloc_pending(struct packet_sock *po)
1218{
1219 po->rx_ring.pending_refcnt = NULL;
1220
1221 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1222 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1223 return -ENOBUFS;
1224
1225 return 0;
1226}
1227
1228static void packet_free_pending(struct packet_sock *po)
1229{
1230 free_percpu(po->tx_ring.pending_refcnt);
1231}
1232
1233#define ROOM_POW_OFF 2
1234#define ROOM_NONE 0x0
1235#define ROOM_LOW 0x1
1236#define ROOM_NORMAL 0x2
1237
1238static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1239{
1240 int idx, len;
1241
1242 len = po->rx_ring.frame_max + 1;
1243 idx = po->rx_ring.head;
1244 if (pow_off)
1245 idx += len >> pow_off;
1246 if (idx >= len)
1247 idx -= len;
1248 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1249}
1250
1251static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1252{
1253 int idx, len;
1254
1255 len = po->rx_ring.prb_bdqc.knum_blocks;
1256 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1257 if (pow_off)
1258 idx += len >> pow_off;
1259 if (idx >= len)
1260 idx -= len;
1261 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1262}
1263
1264static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1265{
1266 struct sock *sk = &po->sk;
1267 int ret = ROOM_NONE;
1268
1269 if (po->prot_hook.func != tpacket_rcv) {
1270 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1271 - (skb ? skb->truesize : 0);
1272 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1273 return ROOM_NORMAL;
1274 else if (avail > 0)
1275 return ROOM_LOW;
1276 else
1277 return ROOM_NONE;
1278 }
1279
1280 if (po->tp_version == TPACKET_V3) {
1281 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1282 ret = ROOM_NORMAL;
1283 else if (__tpacket_v3_has_room(po, 0))
1284 ret = ROOM_LOW;
1285 } else {
1286 if (__tpacket_has_room(po, ROOM_POW_OFF))
1287 ret = ROOM_NORMAL;
1288 else if (__tpacket_has_room(po, 0))
1289 ret = ROOM_LOW;
1290 }
1291
1292 return ret;
1293}
1294
1295static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1296{
1297 int ret;
1298 bool has_room;
1299
1300 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1301 ret = __packet_rcv_has_room(po, skb);
1302 has_room = ret == ROOM_NORMAL;
1303 if (po->pressure == has_room)
1304 po->pressure = !has_room;
1305 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1306
1307 return ret;
1308}
1309
1310static void packet_sock_destruct(struct sock *sk)
1311{
1312 skb_queue_purge(&sk->sk_error_queue);
1313
1314 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1315 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1316
1317 if (!sock_flag(sk, SOCK_DEAD)) {
1318 pr_err("Attempt to release alive packet socket: %p\n", sk);
1319 return;
1320 }
1321
1322 sk_refcnt_debug_dec(sk);
1323}
1324
1325static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1326{
1327 u32 rxhash;
1328 int i, count = 0;
1329
1330 rxhash = skb_get_hash(skb);
1331 for (i = 0; i < ROLLOVER_HLEN; i++)
1332 if (po->rollover->history[i] == rxhash)
1333 count++;
1334
1335 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1336 return count > (ROLLOVER_HLEN >> 1);
1337}
1338
1339static unsigned int fanout_demux_hash(struct packet_fanout *f,
1340 struct sk_buff *skb,
1341 unsigned int num)
1342{
1343 return reciprocal_scale(skb_get_hash(skb), num);
1344}
1345
1346static unsigned int fanout_demux_lb(struct packet_fanout *f,
1347 struct sk_buff *skb,
1348 unsigned int num)
1349{
1350 unsigned int val = atomic_inc_return(&f->rr_cur);
1351
1352 return val % num;
1353}
1354
1355static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1356 struct sk_buff *skb,
1357 unsigned int num)
1358{
1359 return smp_processor_id() % num;
1360}
1361
1362static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1363 struct sk_buff *skb,
1364 unsigned int num)
1365{
1366 return prandom_u32_max(num);
1367}
1368
1369static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1370 struct sk_buff *skb,
1371 unsigned int idx, bool try_self,
1372 unsigned int num)
1373{
1374 struct packet_sock *po, *po_next, *po_skip = NULL;
1375 unsigned int i, j, room = ROOM_NONE;
1376
1377 po = pkt_sk(f->arr[idx]);
1378
1379 if (try_self) {
1380 room = packet_rcv_has_room(po, skb);
1381 if (room == ROOM_NORMAL ||
1382 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1383 return idx;
1384 po_skip = po;
1385 }
1386
1387 i = j = min_t(int, po->rollover->sock, num - 1);
1388 do {
1389 po_next = pkt_sk(f->arr[i]);
1390 if (po_next != po_skip && !po_next->pressure &&
1391 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1392 if (i != j)
1393 po->rollover->sock = i;
1394 atomic_long_inc(&po->rollover->num);
1395 if (room == ROOM_LOW)
1396 atomic_long_inc(&po->rollover->num_huge);
1397 return i;
1398 }
1399
1400 if (++i == num)
1401 i = 0;
1402 } while (i != j);
1403
1404 atomic_long_inc(&po->rollover->num_failed);
1405 return idx;
1406}
1407
1408static unsigned int fanout_demux_qm(struct packet_fanout *f,
1409 struct sk_buff *skb,
1410 unsigned int num)
1411{
1412 return skb_get_queue_mapping(skb) % num;
1413}
1414
1415static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1416 struct sk_buff *skb,
1417 unsigned int num)
1418{
1419 struct bpf_prog *prog;
1420 unsigned int ret = 0;
1421
1422 rcu_read_lock();
1423 prog = rcu_dereference(f->bpf_prog);
1424 if (prog)
1425 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1426 rcu_read_unlock();
1427
1428 return ret;
1429}
1430
1431static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1432{
1433 return f->flags & (flag >> 8);
1434}
1435
1436static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1437 struct packet_type *pt, struct net_device *orig_dev)
1438{
1439 struct packet_fanout *f = pt->af_packet_priv;
1440 unsigned int num = READ_ONCE(f->num_members);
1441 struct net *net = read_pnet(&f->net);
1442 struct packet_sock *po;
1443 unsigned int idx;
1444
1445 if (!net_eq(dev_net(dev), net) || !num) {
1446 kfree_skb(skb);
1447 return 0;
1448 }
1449
1450 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1451 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1452 if (!skb)
1453 return 0;
1454 }
1455 switch (f->type) {
1456 case PACKET_FANOUT_HASH:
1457 default:
1458 idx = fanout_demux_hash(f, skb, num);
1459 break;
1460 case PACKET_FANOUT_LB:
1461 idx = fanout_demux_lb(f, skb, num);
1462 break;
1463 case PACKET_FANOUT_CPU:
1464 idx = fanout_demux_cpu(f, skb, num);
1465 break;
1466 case PACKET_FANOUT_RND:
1467 idx = fanout_demux_rnd(f, skb, num);
1468 break;
1469 case PACKET_FANOUT_QM:
1470 idx = fanout_demux_qm(f, skb, num);
1471 break;
1472 case PACKET_FANOUT_ROLLOVER:
1473 idx = fanout_demux_rollover(f, skb, 0, false, num);
1474 break;
1475 case PACKET_FANOUT_CBPF:
1476 case PACKET_FANOUT_EBPF:
1477 idx = fanout_demux_bpf(f, skb, num);
1478 break;
1479 }
1480
1481 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1482 idx = fanout_demux_rollover(f, skb, idx, true, num);
1483
1484 po = pkt_sk(f->arr[idx]);
1485 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1486}
1487
1488DEFINE_MUTEX(fanout_mutex);
1489EXPORT_SYMBOL_GPL(fanout_mutex);
1490static LIST_HEAD(fanout_list);
1491
1492static void __fanout_link(struct sock *sk, struct packet_sock *po)
1493{
1494 struct packet_fanout *f = po->fanout;
1495
1496 spin_lock(&f->lock);
1497 f->arr[f->num_members] = sk;
1498 smp_wmb();
1499 f->num_members++;
1500 spin_unlock(&f->lock);
1501}
1502
1503static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1504{
1505 struct packet_fanout *f = po->fanout;
1506 int i;
1507
1508 spin_lock(&f->lock);
1509 for (i = 0; i < f->num_members; i++) {
1510 if (f->arr[i] == sk)
1511 break;
1512 }
1513 BUG_ON(i >= f->num_members);
1514 f->arr[i] = f->arr[f->num_members - 1];
1515 f->num_members--;
1516 spin_unlock(&f->lock);
1517}
1518
1519static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1520{
1521 if (sk->sk_family != PF_PACKET)
1522 return false;
1523
1524 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1525}
1526
1527static void fanout_init_data(struct packet_fanout *f)
1528{
1529 switch (f->type) {
1530 case PACKET_FANOUT_LB:
1531 atomic_set(&f->rr_cur, 0);
1532 break;
1533 case PACKET_FANOUT_CBPF:
1534 case PACKET_FANOUT_EBPF:
1535 RCU_INIT_POINTER(f->bpf_prog, NULL);
1536 break;
1537 }
1538}
1539
1540static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1541{
1542 struct bpf_prog *old;
1543
1544 spin_lock(&f->lock);
1545 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1546 rcu_assign_pointer(f->bpf_prog, new);
1547 spin_unlock(&f->lock);
1548
1549 if (old) {
1550 synchronize_net();
1551 bpf_prog_destroy(old);
1552 }
1553}
1554
1555static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1556 unsigned int len)
1557{
1558 struct bpf_prog *new;
1559 struct sock_fprog fprog;
1560 int ret;
1561
1562 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1563 return -EPERM;
1564 if (len != sizeof(fprog))
1565 return -EINVAL;
1566 if (copy_from_user(&fprog, data, len))
1567 return -EFAULT;
1568
1569 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1570 if (ret)
1571 return ret;
1572
1573 __fanout_set_data_bpf(po->fanout, new);
1574 return 0;
1575}
1576
1577static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1578 unsigned int len)
1579{
1580 struct bpf_prog *new;
1581 u32 fd;
1582
1583 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1584 return -EPERM;
1585 if (len != sizeof(fd))
1586 return -EINVAL;
1587 if (copy_from_user(&fd, data, len))
1588 return -EFAULT;
1589
1590 new = bpf_prog_get(fd);
1591 if (IS_ERR(new))
1592 return PTR_ERR(new);
1593 if (new->type != BPF_PROG_TYPE_SOCKET_FILTER) {
1594 bpf_prog_put(new);
1595 return -EINVAL;
1596 }
1597
1598 __fanout_set_data_bpf(po->fanout, new);
1599 return 0;
1600}
1601
1602static int fanout_set_data(struct packet_sock *po, char __user *data,
1603 unsigned int len)
1604{
1605 switch (po->fanout->type) {
1606 case PACKET_FANOUT_CBPF:
1607 return fanout_set_data_cbpf(po, data, len);
1608 case PACKET_FANOUT_EBPF:
1609 return fanout_set_data_ebpf(po, data, len);
1610 default:
1611 return -EINVAL;
1612 };
1613}
1614
1615static void fanout_release_data(struct packet_fanout *f)
1616{
1617 switch (f->type) {
1618 case PACKET_FANOUT_CBPF:
1619 case PACKET_FANOUT_EBPF:
1620 __fanout_set_data_bpf(f, NULL);
1621 };
1622}
1623
1624static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1625{
1626 struct packet_sock *po = pkt_sk(sk);
1627 struct packet_fanout *f, *match;
1628 u8 type = type_flags & 0xff;
1629 u8 flags = type_flags >> 8;
1630 int err;
1631
1632 switch (type) {
1633 case PACKET_FANOUT_ROLLOVER:
1634 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1635 return -EINVAL;
1636 case PACKET_FANOUT_HASH:
1637 case PACKET_FANOUT_LB:
1638 case PACKET_FANOUT_CPU:
1639 case PACKET_FANOUT_RND:
1640 case PACKET_FANOUT_QM:
1641 case PACKET_FANOUT_CBPF:
1642 case PACKET_FANOUT_EBPF:
1643 break;
1644 default:
1645 return -EINVAL;
1646 }
1647
1648 if (!po->running)
1649 return -EINVAL;
1650
1651 if (po->fanout)
1652 return -EALREADY;
1653
1654 if (type == PACKET_FANOUT_ROLLOVER ||
1655 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1656 po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
1657 if (!po->rollover)
1658 return -ENOMEM;
1659 atomic_long_set(&po->rollover->num, 0);
1660 atomic_long_set(&po->rollover->num_huge, 0);
1661 atomic_long_set(&po->rollover->num_failed, 0);
1662 }
1663
1664 mutex_lock(&fanout_mutex);
1665 match = NULL;
1666 list_for_each_entry(f, &fanout_list, list) {
1667 if (f->id == id &&
1668 read_pnet(&f->net) == sock_net(sk)) {
1669 match = f;
1670 break;
1671 }
1672 }
1673 err = -EINVAL;
1674 if (match && match->flags != flags)
1675 goto out;
1676 if (!match) {
1677 err = -ENOMEM;
1678 match = kzalloc(sizeof(*match), GFP_KERNEL);
1679 if (!match)
1680 goto out;
1681 write_pnet(&match->net, sock_net(sk));
1682 match->id = id;
1683 match->type = type;
1684 match->flags = flags;
1685 INIT_LIST_HEAD(&match->list);
1686 spin_lock_init(&match->lock);
1687 atomic_set(&match->sk_ref, 0);
1688 fanout_init_data(match);
1689 match->prot_hook.type = po->prot_hook.type;
1690 match->prot_hook.dev = po->prot_hook.dev;
1691 match->prot_hook.func = packet_rcv_fanout;
1692 match->prot_hook.af_packet_priv = match;
1693 match->prot_hook.id_match = match_fanout_group;
1694 dev_add_pack(&match->prot_hook);
1695 list_add(&match->list, &fanout_list);
1696 }
1697 err = -EINVAL;
1698 if (match->type == type &&
1699 match->prot_hook.type == po->prot_hook.type &&
1700 match->prot_hook.dev == po->prot_hook.dev) {
1701 err = -ENOSPC;
1702 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1703 __dev_remove_pack(&po->prot_hook);
1704 po->fanout = match;
1705 atomic_inc(&match->sk_ref);
1706 __fanout_link(sk, po);
1707 err = 0;
1708 }
1709 }
1710out:
1711 mutex_unlock(&fanout_mutex);
1712 if (err) {
1713 kfree(po->rollover);
1714 po->rollover = NULL;
1715 }
1716 return err;
1717}
1718
1719static void fanout_release(struct sock *sk)
1720{
1721 struct packet_sock *po = pkt_sk(sk);
1722 struct packet_fanout *f;
1723
1724 f = po->fanout;
1725 if (!f)
1726 return;
1727
1728 mutex_lock(&fanout_mutex);
1729 po->fanout = NULL;
1730
1731 if (atomic_dec_and_test(&f->sk_ref)) {
1732 list_del(&f->list);
1733 dev_remove_pack(&f->prot_hook);
1734 fanout_release_data(f);
1735 kfree(f);
1736 }
1737 mutex_unlock(&fanout_mutex);
1738
1739 if (po->rollover)
1740 kfree_rcu(po->rollover, rcu);
1741}
1742
1743static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1744 struct sk_buff *skb)
1745{
1746 /* Earlier code assumed this would be a VLAN pkt, double-check
1747 * this now that we have the actual packet in hand. We can only
1748 * do this check on Ethernet devices.
1749 */
1750 if (unlikely(dev->type != ARPHRD_ETHER))
1751 return false;
1752
1753 skb_reset_mac_header(skb);
1754 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1755}
1756
1757static const struct proto_ops packet_ops;
1758
1759static const struct proto_ops packet_ops_spkt;
1760
1761static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1762 struct packet_type *pt, struct net_device *orig_dev)
1763{
1764 struct sock *sk;
1765 struct sockaddr_pkt *spkt;
1766
1767 /*
1768 * When we registered the protocol we saved the socket in the data
1769 * field for just this event.
1770 */
1771
1772 sk = pt->af_packet_priv;
1773
1774 /*
1775 * Yank back the headers [hope the device set this
1776 * right or kerboom...]
1777 *
1778 * Incoming packets have ll header pulled,
1779 * push it back.
1780 *
1781 * For outgoing ones skb->data == skb_mac_header(skb)
1782 * so that this procedure is noop.
1783 */
1784
1785 if (skb->pkt_type == PACKET_LOOPBACK)
1786 goto out;
1787
1788 if (!net_eq(dev_net(dev), sock_net(sk)))
1789 goto out;
1790
1791 skb = skb_share_check(skb, GFP_ATOMIC);
1792 if (skb == NULL)
1793 goto oom;
1794
1795 /* drop any routing info */
1796 skb_dst_drop(skb);
1797
1798 /* drop conntrack reference */
1799 nf_reset(skb);
1800
1801 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1802
1803 skb_push(skb, skb->data - skb_mac_header(skb));
1804
1805 /*
1806 * The SOCK_PACKET socket receives _all_ frames.
1807 */
1808
1809 spkt->spkt_family = dev->type;
1810 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1811 spkt->spkt_protocol = skb->protocol;
1812
1813 /*
1814 * Charge the memory to the socket. This is done specifically
1815 * to prevent sockets using all the memory up.
1816 */
1817
1818 if (sock_queue_rcv_skb(sk, skb) == 0)
1819 return 0;
1820
1821out:
1822 kfree_skb(skb);
1823oom:
1824 return 0;
1825}
1826
1827
1828/*
1829 * Output a raw packet to a device layer. This bypasses all the other
1830 * protocol layers and you must therefore supply it with a complete frame
1831 */
1832
1833static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1834 size_t len)
1835{
1836 struct sock *sk = sock->sk;
1837 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1838 struct sk_buff *skb = NULL;
1839 struct net_device *dev;
1840 __be16 proto = 0;
1841 int err;
1842 int extra_len = 0;
1843
1844 /*
1845 * Get and verify the address.
1846 */
1847
1848 if (saddr) {
1849 if (msg->msg_namelen < sizeof(struct sockaddr))
1850 return -EINVAL;
1851 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1852 proto = saddr->spkt_protocol;
1853 } else
1854 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1855
1856 /*
1857 * Find the device first to size check it
1858 */
1859
1860 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1861retry:
1862 rcu_read_lock();
1863 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1864 err = -ENODEV;
1865 if (dev == NULL)
1866 goto out_unlock;
1867
1868 err = -ENETDOWN;
1869 if (!(dev->flags & IFF_UP))
1870 goto out_unlock;
1871
1872 /*
1873 * You may not queue a frame bigger than the mtu. This is the lowest level
1874 * raw protocol and you must do your own fragmentation at this level.
1875 */
1876
1877 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1878 if (!netif_supports_nofcs(dev)) {
1879 err = -EPROTONOSUPPORT;
1880 goto out_unlock;
1881 }
1882 extra_len = 4; /* We're doing our own CRC */
1883 }
1884
1885 err = -EMSGSIZE;
1886 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1887 goto out_unlock;
1888
1889 if (!skb) {
1890 size_t reserved = LL_RESERVED_SPACE(dev);
1891 int tlen = dev->needed_tailroom;
1892 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1893
1894 rcu_read_unlock();
1895 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1896 if (skb == NULL)
1897 return -ENOBUFS;
1898 /* FIXME: Save some space for broken drivers that write a hard
1899 * header at transmission time by themselves. PPP is the notable
1900 * one here. This should really be fixed at the driver level.
1901 */
1902 skb_reserve(skb, reserved);
1903 skb_reset_network_header(skb);
1904
1905 /* Try to align data part correctly */
1906 if (hhlen) {
1907 skb->data -= hhlen;
1908 skb->tail -= hhlen;
1909 if (len < hhlen)
1910 skb_reset_network_header(skb);
1911 }
1912 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1913 if (err)
1914 goto out_free;
1915 goto retry;
1916 }
1917
1918 if (!dev_validate_header(dev, skb->data, len)) {
1919 err = -EINVAL;
1920 goto out_unlock;
1921 }
1922 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1923 !packet_extra_vlan_len_allowed(dev, skb)) {
1924 err = -EMSGSIZE;
1925 goto out_unlock;
1926 }
1927
1928 skb->protocol = proto;
1929 skb->dev = dev;
1930 skb->priority = sk->sk_priority;
1931 skb->mark = sk->sk_mark;
1932
1933 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1934
1935 if (unlikely(extra_len == 4))
1936 skb->no_fcs = 1;
1937
1938 skb_probe_transport_header(skb, 0);
1939
1940 dev_queue_xmit(skb);
1941 rcu_read_unlock();
1942 return len;
1943
1944out_unlock:
1945 rcu_read_unlock();
1946out_free:
1947 kfree_skb(skb);
1948 return err;
1949}
1950
1951static unsigned int run_filter(struct sk_buff *skb,
1952 const struct sock *sk,
1953 unsigned int res)
1954{
1955 struct sk_filter *filter;
1956
1957 rcu_read_lock();
1958 filter = rcu_dereference(sk->sk_filter);
1959 if (filter != NULL)
1960 res = bpf_prog_run_clear_cb(filter->prog, skb);
1961 rcu_read_unlock();
1962
1963 return res;
1964}
1965
1966static int __packet_rcv_vnet(const struct sk_buff *skb,
1967 struct virtio_net_hdr *vnet_hdr)
1968{
1969 *vnet_hdr = (const struct virtio_net_hdr) { 0 };
1970
1971 if (skb_is_gso(skb)) {
1972 struct skb_shared_info *sinfo = skb_shinfo(skb);
1973
1974 /* This is a hint as to how much should be linear. */
1975 vnet_hdr->hdr_len =
1976 __cpu_to_virtio16(vio_le(), skb_headlen(skb));
1977 vnet_hdr->gso_size =
1978 __cpu_to_virtio16(vio_le(), sinfo->gso_size);
1979
1980 if (sinfo->gso_type & SKB_GSO_TCPV4)
1981 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1982 else if (sinfo->gso_type & SKB_GSO_TCPV6)
1983 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1984 else if (sinfo->gso_type & SKB_GSO_UDP)
1985 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
1986 else if (sinfo->gso_type & SKB_GSO_FCOE)
1987 return -EINVAL;
1988 else
1989 BUG();
1990
1991 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1992 vnet_hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1993 } else
1994 vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
1995
1996 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1997 vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1998 vnet_hdr->csum_start = __cpu_to_virtio16(vio_le(),
1999 skb_checksum_start_offset(skb));
2000 vnet_hdr->csum_offset = __cpu_to_virtio16(vio_le(),
2001 skb->csum_offset);
2002 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2003 vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
2004 } /* else everything is zero */
2005
2006 return 0;
2007}
2008
2009static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2010 size_t *len)
2011{
2012 struct virtio_net_hdr vnet_hdr;
2013
2014 if (*len < sizeof(vnet_hdr))
2015 return -EINVAL;
2016 *len -= sizeof(vnet_hdr);
2017
2018 if (__packet_rcv_vnet(skb, &vnet_hdr))
2019 return -EINVAL;
2020
2021 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
2022}
2023
2024/*
2025 * This function makes lazy skb cloning in hope that most of packets
2026 * are discarded by BPF.
2027 *
2028 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2029 * and skb->cb are mangled. It works because (and until) packets
2030 * falling here are owned by current CPU. Output packets are cloned
2031 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2032 * sequencially, so that if we return skb to original state on exit,
2033 * we will not harm anyone.
2034 */
2035
2036static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2037 struct packet_type *pt, struct net_device *orig_dev)
2038{
2039 struct sock *sk;
2040 struct sockaddr_ll *sll;
2041 struct packet_sock *po;
2042 u8 *skb_head = skb->data;
2043 int skb_len = skb->len;
2044 unsigned int snaplen, res;
2045
2046 if (skb->pkt_type == PACKET_LOOPBACK)
2047 goto drop;
2048
2049 sk = pt->af_packet_priv;
2050 po = pkt_sk(sk);
2051
2052 if (!net_eq(dev_net(dev), sock_net(sk)))
2053 goto drop;
2054
2055 skb->dev = dev;
2056
2057 if (dev->header_ops) {
2058 /* The device has an explicit notion of ll header,
2059 * exported to higher levels.
2060 *
2061 * Otherwise, the device hides details of its frame
2062 * structure, so that corresponding packet head is
2063 * never delivered to user.
2064 */
2065 if (sk->sk_type != SOCK_DGRAM)
2066 skb_push(skb, skb->data - skb_mac_header(skb));
2067 else if (skb->pkt_type == PACKET_OUTGOING) {
2068 /* Special case: outgoing packets have ll header at head */
2069 skb_pull(skb, skb_network_offset(skb));
2070 }
2071 }
2072
2073 snaplen = skb->len;
2074
2075 res = run_filter(skb, sk, snaplen);
2076 if (!res)
2077 goto drop_n_restore;
2078 if (snaplen > res)
2079 snaplen = res;
2080
2081 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2082 goto drop_n_acct;
2083
2084 if (skb_shared(skb)) {
2085 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2086 if (nskb == NULL)
2087 goto drop_n_acct;
2088
2089 if (skb_head != skb->data) {
2090 skb->data = skb_head;
2091 skb->len = skb_len;
2092 }
2093 consume_skb(skb);
2094 skb = nskb;
2095 }
2096
2097 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2098
2099 sll = &PACKET_SKB_CB(skb)->sa.ll;
2100 sll->sll_hatype = dev->type;
2101 sll->sll_pkttype = skb->pkt_type;
2102 if (unlikely(po->origdev))
2103 sll->sll_ifindex = orig_dev->ifindex;
2104 else
2105 sll->sll_ifindex = dev->ifindex;
2106
2107 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2108
2109 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2110 * Use their space for storing the original skb length.
2111 */
2112 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2113
2114 if (pskb_trim(skb, snaplen))
2115 goto drop_n_acct;
2116
2117 skb_set_owner_r(skb, sk);
2118 skb->dev = NULL;
2119 skb_dst_drop(skb);
2120
2121 /* drop conntrack reference */
2122 nf_reset(skb);
2123
2124 spin_lock(&sk->sk_receive_queue.lock);
2125 po->stats.stats1.tp_packets++;
2126 sock_skb_set_dropcount(sk, skb);
2127 __skb_queue_tail(&sk->sk_receive_queue, skb);
2128 spin_unlock(&sk->sk_receive_queue.lock);
2129 sk->sk_data_ready(sk);
2130 return 0;
2131
2132drop_n_acct:
2133 spin_lock(&sk->sk_receive_queue.lock);
2134 po->stats.stats1.tp_drops++;
2135 atomic_inc(&sk->sk_drops);
2136 spin_unlock(&sk->sk_receive_queue.lock);
2137
2138drop_n_restore:
2139 if (skb_head != skb->data && skb_shared(skb)) {
2140 skb->data = skb_head;
2141 skb->len = skb_len;
2142 }
2143drop:
2144 consume_skb(skb);
2145 return 0;
2146}
2147
2148static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2149 struct packet_type *pt, struct net_device *orig_dev)
2150{
2151 struct sock *sk;
2152 struct packet_sock *po;
2153 struct sockaddr_ll *sll;
2154 union tpacket_uhdr h;
2155 u8 *skb_head = skb->data;
2156 int skb_len = skb->len;
2157 unsigned int snaplen, res;
2158 unsigned long status = TP_STATUS_USER;
2159 unsigned short macoff, netoff, hdrlen;
2160 struct sk_buff *copy_skb = NULL;
2161 struct timespec ts;
2162 __u32 ts_status;
2163
2164 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2165 * We may add members to them until current aligned size without forcing
2166 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2167 */
2168 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2169 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2170
2171 if (skb->pkt_type == PACKET_LOOPBACK)
2172 goto drop;
2173
2174 sk = pt->af_packet_priv;
2175 po = pkt_sk(sk);
2176
2177 if (!net_eq(dev_net(dev), sock_net(sk)))
2178 goto drop;
2179
2180 if (dev->header_ops) {
2181 if (sk->sk_type != SOCK_DGRAM)
2182 skb_push(skb, skb->data - skb_mac_header(skb));
2183 else if (skb->pkt_type == PACKET_OUTGOING) {
2184 /* Special case: outgoing packets have ll header at head */
2185 skb_pull(skb, skb_network_offset(skb));
2186 }
2187 }
2188
2189 snaplen = skb->len;
2190
2191 res = run_filter(skb, sk, snaplen);
2192 if (!res)
2193 goto drop_n_restore;
2194
2195 if (skb->ip_summed == CHECKSUM_PARTIAL)
2196 status |= TP_STATUS_CSUMNOTREADY;
2197 else if (skb->pkt_type != PACKET_OUTGOING &&
2198 (skb->ip_summed == CHECKSUM_COMPLETE ||
2199 skb_csum_unnecessary(skb)))
2200 status |= TP_STATUS_CSUM_VALID;
2201
2202 if (snaplen > res)
2203 snaplen = res;
2204
2205 if (sk->sk_type == SOCK_DGRAM) {
2206 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2207 po->tp_reserve;
2208 } else {
2209 unsigned int maclen = skb_network_offset(skb);
2210 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2211 (maclen < 16 ? 16 : maclen)) +
2212 po->tp_reserve;
2213 if (po->has_vnet_hdr)
2214 netoff += sizeof(struct virtio_net_hdr);
2215 macoff = netoff - maclen;
2216 }
2217 if (po->tp_version <= TPACKET_V2) {
2218 if (macoff + snaplen > po->rx_ring.frame_size) {
2219 if (po->copy_thresh &&
2220 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2221 if (skb_shared(skb)) {
2222 copy_skb = skb_clone(skb, GFP_ATOMIC);
2223 } else {
2224 copy_skb = skb_get(skb);
2225 skb_head = skb->data;
2226 }
2227 if (copy_skb)
2228 skb_set_owner_r(copy_skb, sk);
2229 }
2230 snaplen = po->rx_ring.frame_size - macoff;
2231 if ((int)snaplen < 0)
2232 snaplen = 0;
2233 }
2234 } else if (unlikely(macoff + snaplen >
2235 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2236 u32 nval;
2237
2238 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2239 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2240 snaplen, nval, macoff);
2241 snaplen = nval;
2242 if (unlikely((int)snaplen < 0)) {
2243 snaplen = 0;
2244 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2245 }
2246 }
2247 spin_lock(&sk->sk_receive_queue.lock);
2248 h.raw = packet_current_rx_frame(po, skb,
2249 TP_STATUS_KERNEL, (macoff+snaplen));
2250 if (!h.raw)
2251 goto drop_n_account;
2252 if (po->tp_version <= TPACKET_V2) {
2253 packet_increment_rx_head(po, &po->rx_ring);
2254 /*
2255 * LOSING will be reported till you read the stats,
2256 * because it's COR - Clear On Read.
2257 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2258 * at packet level.
2259 */
2260 if (po->stats.stats1.tp_drops)
2261 status |= TP_STATUS_LOSING;
2262 }
2263 po->stats.stats1.tp_packets++;
2264 if (copy_skb) {
2265 status |= TP_STATUS_COPY;
2266 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2267 }
2268 spin_unlock(&sk->sk_receive_queue.lock);
2269
2270 if (po->has_vnet_hdr) {
2271 if (__packet_rcv_vnet(skb, h.raw + macoff -
2272 sizeof(struct virtio_net_hdr))) {
2273 spin_lock(&sk->sk_receive_queue.lock);
2274 goto drop_n_account;
2275 }
2276 }
2277
2278 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2279
2280 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2281 getnstimeofday(&ts);
2282
2283 status |= ts_status;
2284
2285 switch (po->tp_version) {
2286 case TPACKET_V1:
2287 h.h1->tp_len = skb->len;
2288 h.h1->tp_snaplen = snaplen;
2289 h.h1->tp_mac = macoff;
2290 h.h1->tp_net = netoff;
2291 h.h1->tp_sec = ts.tv_sec;
2292 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2293 hdrlen = sizeof(*h.h1);
2294 break;
2295 case TPACKET_V2:
2296 h.h2->tp_len = skb->len;
2297 h.h2->tp_snaplen = snaplen;
2298 h.h2->tp_mac = macoff;
2299 h.h2->tp_net = netoff;
2300 h.h2->tp_sec = ts.tv_sec;
2301 h.h2->tp_nsec = ts.tv_nsec;
2302 if (skb_vlan_tag_present(skb)) {
2303 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2304 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2305 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2306 } else {
2307 h.h2->tp_vlan_tci = 0;
2308 h.h2->tp_vlan_tpid = 0;
2309 }
2310 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2311 hdrlen = sizeof(*h.h2);
2312 break;
2313 case TPACKET_V3:
2314 /* tp_nxt_offset,vlan are already populated above.
2315 * So DONT clear those fields here
2316 */
2317 h.h3->tp_status |= status;
2318 h.h3->tp_len = skb->len;
2319 h.h3->tp_snaplen = snaplen;
2320 h.h3->tp_mac = macoff;
2321 h.h3->tp_net = netoff;
2322 h.h3->tp_sec = ts.tv_sec;
2323 h.h3->tp_nsec = ts.tv_nsec;
2324 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2325 hdrlen = sizeof(*h.h3);
2326 break;
2327 default:
2328 BUG();
2329 }
2330
2331 sll = h.raw + TPACKET_ALIGN(hdrlen);
2332 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2333 sll->sll_family = AF_PACKET;
2334 sll->sll_hatype = dev->type;
2335 sll->sll_protocol = skb->protocol;
2336 sll->sll_pkttype = skb->pkt_type;
2337 if (unlikely(po->origdev))
2338 sll->sll_ifindex = orig_dev->ifindex;
2339 else
2340 sll->sll_ifindex = dev->ifindex;
2341
2342 smp_mb();
2343
2344#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2345 if (po->tp_version <= TPACKET_V2) {
2346 u8 *start, *end;
2347
2348 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2349 macoff + snaplen);
2350
2351 for (start = h.raw; start < end; start += PAGE_SIZE)
2352 flush_dcache_page(pgv_to_page(start));
2353 }
2354 smp_wmb();
2355#endif
2356
2357 if (po->tp_version <= TPACKET_V2) {
2358 __packet_set_status(po, h.raw, status);
2359 sk->sk_data_ready(sk);
2360 } else {
2361 prb_clear_blk_fill_status(&po->rx_ring);
2362 }
2363
2364drop_n_restore:
2365 if (skb_head != skb->data && skb_shared(skb)) {
2366 skb->data = skb_head;
2367 skb->len = skb_len;
2368 }
2369drop:
2370 kfree_skb(skb);
2371 return 0;
2372
2373drop_n_account:
2374 po->stats.stats1.tp_drops++;
2375 spin_unlock(&sk->sk_receive_queue.lock);
2376
2377 sk->sk_data_ready(sk);
2378 kfree_skb(copy_skb);
2379 goto drop_n_restore;
2380}
2381
2382static void tpacket_destruct_skb(struct sk_buff *skb)
2383{
2384 struct packet_sock *po = pkt_sk(skb->sk);
2385
2386 if (likely(po->tx_ring.pg_vec)) {
2387 void *ph;
2388 __u32 ts;
2389
2390 ph = skb_shinfo(skb)->destructor_arg;
2391 packet_dec_pending(&po->tx_ring);
2392
2393 ts = __packet_set_timestamp(po, ph, skb);
2394 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2395 }
2396
2397 sock_wfree(skb);
2398}
2399
2400static void tpacket_set_protocol(const struct net_device *dev,
2401 struct sk_buff *skb)
2402{
2403 if (dev->type == ARPHRD_ETHER) {
2404 skb_reset_mac_header(skb);
2405 skb->protocol = eth_hdr(skb)->h_proto;
2406 }
2407}
2408
2409static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2410{
2411 unsigned short gso_type = 0;
2412
2413 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2414 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2415 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2416 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2417 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2418 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2419 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2420
2421 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2422 return -EINVAL;
2423
2424 if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2425 switch (vnet_hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2426 case VIRTIO_NET_HDR_GSO_TCPV4:
2427 gso_type = SKB_GSO_TCPV4;
2428 break;
2429 case VIRTIO_NET_HDR_GSO_TCPV6:
2430 gso_type = SKB_GSO_TCPV6;
2431 break;
2432 case VIRTIO_NET_HDR_GSO_UDP:
2433 gso_type = SKB_GSO_UDP;
2434 break;
2435 default:
2436 return -EINVAL;
2437 }
2438
2439 if (vnet_hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
2440 gso_type |= SKB_GSO_TCP_ECN;
2441
2442 if (vnet_hdr->gso_size == 0)
2443 return -EINVAL;
2444 }
2445
2446 vnet_hdr->gso_type = gso_type; /* changes type, temporary storage */
2447 return 0;
2448}
2449
2450static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2451 struct virtio_net_hdr *vnet_hdr)
2452{
2453 int n;
2454
2455 if (*len < sizeof(*vnet_hdr))
2456 return -EINVAL;
2457 *len -= sizeof(*vnet_hdr);
2458
2459 n = copy_from_iter(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter);
2460 if (n != sizeof(*vnet_hdr))
2461 return -EFAULT;
2462
2463 return __packet_snd_vnet_parse(vnet_hdr, *len);
2464}
2465
2466static int packet_snd_vnet_gso(struct sk_buff *skb,
2467 struct virtio_net_hdr *vnet_hdr)
2468{
2469 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2470 u16 s = __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start);
2471 u16 o = __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset);
2472
2473 if (!skb_partial_csum_set(skb, s, o))
2474 return -EINVAL;
2475 }
2476
2477 skb_shinfo(skb)->gso_size =
2478 __virtio16_to_cpu(vio_le(), vnet_hdr->gso_size);
2479 skb_shinfo(skb)->gso_type = vnet_hdr->gso_type;
2480
2481 /* Header must be checked, and gso_segs computed. */
2482 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2483 skb_shinfo(skb)->gso_segs = 0;
2484 return 0;
2485}
2486
2487static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2488 void *frame, struct net_device *dev, void *data, int tp_len,
2489 __be16 proto, unsigned char *addr, int hlen, int copylen)
2490{
2491 union tpacket_uhdr ph;
2492 int to_write, offset, len, nr_frags, len_max;
2493 struct socket *sock = po->sk.sk_socket;
2494 struct page *page;
2495 int err;
2496
2497 ph.raw = frame;
2498
2499 skb->protocol = proto;
2500 skb->dev = dev;
2501 skb->priority = po->sk.sk_priority;
2502 skb->mark = po->sk.sk_mark;
2503 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2504 skb_shinfo(skb)->destructor_arg = ph.raw;
2505
2506 skb_reserve(skb, hlen);
2507 skb_reset_network_header(skb);
2508
2509 to_write = tp_len;
2510
2511 if (sock->type == SOCK_DGRAM) {
2512 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2513 NULL, tp_len);
2514 if (unlikely(err < 0))
2515 return -EINVAL;
2516 } else if (copylen) {
2517 int hdrlen = min_t(int, copylen, tp_len);
2518
2519 skb_push(skb, dev->hard_header_len);
2520 skb_put(skb, copylen - dev->hard_header_len);
2521 err = skb_store_bits(skb, 0, data, hdrlen);
2522 if (unlikely(err))
2523 return err;
2524 if (!dev_validate_header(dev, skb->data, hdrlen))
2525 return -EINVAL;
2526 if (!skb->protocol)
2527 tpacket_set_protocol(dev, skb);
2528
2529 data += hdrlen;
2530 to_write -= hdrlen;
2531 }
2532
2533 offset = offset_in_page(data);
2534 len_max = PAGE_SIZE - offset;
2535 len = ((to_write > len_max) ? len_max : to_write);
2536
2537 skb->data_len = to_write;
2538 skb->len += to_write;
2539 skb->truesize += to_write;
2540 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2541
2542 while (likely(to_write)) {
2543 nr_frags = skb_shinfo(skb)->nr_frags;
2544
2545 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2546 pr_err("Packet exceed the number of skb frags(%lu)\n",
2547 MAX_SKB_FRAGS);
2548 return -EFAULT;
2549 }
2550
2551 page = pgv_to_page(data);
2552 data += len;
2553 flush_dcache_page(page);
2554 get_page(page);
2555 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2556 to_write -= len;
2557 offset = 0;
2558 len_max = PAGE_SIZE;
2559 len = ((to_write > len_max) ? len_max : to_write);
2560 }
2561
2562 skb_probe_transport_header(skb, 0);
2563
2564 return tp_len;
2565}
2566
2567static int tpacket_parse_header(struct packet_sock *po, void *frame,
2568 int size_max, void **data)
2569{
2570 union tpacket_uhdr ph;
2571 int tp_len, off;
2572
2573 ph.raw = frame;
2574
2575 switch (po->tp_version) {
2576 case TPACKET_V2:
2577 tp_len = ph.h2->tp_len;
2578 break;
2579 default:
2580 tp_len = ph.h1->tp_len;
2581 break;
2582 }
2583 if (unlikely(tp_len > size_max)) {
2584 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2585 return -EMSGSIZE;
2586 }
2587
2588 if (unlikely(po->tp_tx_has_off)) {
2589 int off_min, off_max;
2590
2591 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2592 off_max = po->tx_ring.frame_size - tp_len;
2593 if (po->sk.sk_type == SOCK_DGRAM) {
2594 switch (po->tp_version) {
2595 case TPACKET_V2:
2596 off = ph.h2->tp_net;
2597 break;
2598 default:
2599 off = ph.h1->tp_net;
2600 break;
2601 }
2602 } else {
2603 switch (po->tp_version) {
2604 case TPACKET_V2:
2605 off = ph.h2->tp_mac;
2606 break;
2607 default:
2608 off = ph.h1->tp_mac;
2609 break;
2610 }
2611 }
2612 if (unlikely((off < off_min) || (off_max < off)))
2613 return -EINVAL;
2614 } else {
2615 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2616 }
2617
2618 *data = frame + off;
2619 return tp_len;
2620}
2621
2622static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2623{
2624 struct sk_buff *skb;
2625 struct net_device *dev;
2626 struct virtio_net_hdr *vnet_hdr = NULL;
2627 __be16 proto;
2628 int err, reserve = 0;
2629 void *ph;
2630 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2631 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2632 int tp_len, size_max;
2633 unsigned char *addr;
2634 void *data;
2635 int len_sum = 0;
2636 int status = TP_STATUS_AVAILABLE;
2637 int hlen, tlen, copylen = 0;
2638
2639 mutex_lock(&po->pg_vec_lock);
2640
2641 if (likely(saddr == NULL)) {
2642 dev = packet_cached_dev_get(po);
2643 proto = po->num;
2644 addr = NULL;
2645 } else {
2646 err = -EINVAL;
2647 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2648 goto out;
2649 if (msg->msg_namelen < (saddr->sll_halen
2650 + offsetof(struct sockaddr_ll,
2651 sll_addr)))
2652 goto out;
2653 proto = saddr->sll_protocol;
2654 addr = saddr->sll_addr;
2655 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2656 }
2657
2658 err = -ENXIO;
2659 if (unlikely(dev == NULL))
2660 goto out;
2661 err = -ENETDOWN;
2662 if (unlikely(!(dev->flags & IFF_UP)))
2663 goto out_put;
2664
2665 if (po->sk.sk_socket->type == SOCK_RAW)
2666 reserve = dev->hard_header_len;
2667 size_max = po->tx_ring.frame_size
2668 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2669
2670 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2671 size_max = dev->mtu + reserve + VLAN_HLEN;
2672
2673 do {
2674 ph = packet_current_frame(po, &po->tx_ring,
2675 TP_STATUS_SEND_REQUEST);
2676 if (unlikely(ph == NULL)) {
2677 if (need_wait && need_resched())
2678 schedule();
2679 continue;
2680 }
2681
2682 skb = NULL;
2683 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2684 if (tp_len < 0)
2685 goto tpacket_error;
2686
2687 status = TP_STATUS_SEND_REQUEST;
2688 hlen = LL_RESERVED_SPACE(dev);
2689 tlen = dev->needed_tailroom;
2690 if (po->has_vnet_hdr) {
2691 vnet_hdr = data;
2692 data += sizeof(*vnet_hdr);
2693 tp_len -= sizeof(*vnet_hdr);
2694 if (tp_len < 0 ||
2695 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2696 tp_len = -EINVAL;
2697 goto tpacket_error;
2698 }
2699 copylen = __virtio16_to_cpu(vio_le(),
2700 vnet_hdr->hdr_len);
2701 }
2702 copylen = max_t(int, copylen, dev->hard_header_len);
2703 skb = sock_alloc_send_skb(&po->sk,
2704 hlen + tlen + sizeof(struct sockaddr_ll) +
2705 (copylen - dev->hard_header_len),
2706 !need_wait, &err);
2707
2708 if (unlikely(skb == NULL)) {
2709 /* we assume the socket was initially writeable ... */
2710 if (likely(len_sum > 0))
2711 err = len_sum;
2712 goto out_status;
2713 }
2714 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2715 addr, hlen, copylen);
2716 if (likely(tp_len >= 0) &&
2717 tp_len > dev->mtu + reserve &&
2718 !po->has_vnet_hdr &&
2719 !packet_extra_vlan_len_allowed(dev, skb))
2720 tp_len = -EMSGSIZE;
2721
2722 if (unlikely(tp_len < 0)) {
2723tpacket_error:
2724 if (po->tp_loss) {
2725 __packet_set_status(po, ph,
2726 TP_STATUS_AVAILABLE);
2727 packet_increment_head(&po->tx_ring);
2728 kfree_skb(skb);
2729 continue;
2730 } else {
2731 status = TP_STATUS_WRONG_FORMAT;
2732 err = tp_len;
2733 goto out_status;
2734 }
2735 }
2736
2737 if (po->has_vnet_hdr && packet_snd_vnet_gso(skb, vnet_hdr)) {
2738 tp_len = -EINVAL;
2739 goto tpacket_error;
2740 }
2741
2742 packet_pick_tx_queue(dev, skb);
2743
2744 skb->destructor = tpacket_destruct_skb;
2745 __packet_set_status(po, ph, TP_STATUS_SENDING);
2746 packet_inc_pending(&po->tx_ring);
2747
2748 status = TP_STATUS_SEND_REQUEST;
2749 err = po->xmit(skb);
2750 if (unlikely(err > 0)) {
2751 err = net_xmit_errno(err);
2752 if (err && __packet_get_status(po, ph) ==
2753 TP_STATUS_AVAILABLE) {
2754 /* skb was destructed already */
2755 skb = NULL;
2756 goto out_status;
2757 }
2758 /*
2759 * skb was dropped but not destructed yet;
2760 * let's treat it like congestion or err < 0
2761 */
2762 err = 0;
2763 }
2764 packet_increment_head(&po->tx_ring);
2765 len_sum += tp_len;
2766 } while (likely((ph != NULL) ||
2767 /* Note: packet_read_pending() might be slow if we have
2768 * to call it as it's per_cpu variable, but in fast-path
2769 * we already short-circuit the loop with the first
2770 * condition, and luckily don't have to go that path
2771 * anyway.
2772 */
2773 (need_wait && packet_read_pending(&po->tx_ring))));
2774
2775 err = len_sum;
2776 goto out_put;
2777
2778out_status:
2779 __packet_set_status(po, ph, status);
2780 kfree_skb(skb);
2781out_put:
2782 dev_put(dev);
2783out:
2784 mutex_unlock(&po->pg_vec_lock);
2785 return err;
2786}
2787
2788static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2789 size_t reserve, size_t len,
2790 size_t linear, int noblock,
2791 int *err)
2792{
2793 struct sk_buff *skb;
2794
2795 /* Under a page? Don't bother with paged skb. */
2796 if (prepad + len < PAGE_SIZE || !linear)
2797 linear = len;
2798
2799 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2800 err, 0);
2801 if (!skb)
2802 return NULL;
2803
2804 skb_reserve(skb, reserve);
2805 skb_put(skb, linear);
2806 skb->data_len = len - linear;
2807 skb->len += len - linear;
2808
2809 return skb;
2810}
2811
2812static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2813{
2814 struct sock *sk = sock->sk;
2815 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2816 struct sk_buff *skb;
2817 struct net_device *dev;
2818 __be16 proto;
2819 unsigned char *addr;
2820 int err, reserve = 0;
2821 struct sockcm_cookie sockc;
2822 struct virtio_net_hdr vnet_hdr = { 0 };
2823 int offset = 0;
2824 struct packet_sock *po = pkt_sk(sk);
2825 int hlen, tlen;
2826 int extra_len = 0;
2827
2828 /*
2829 * Get and verify the address.
2830 */
2831
2832 if (likely(saddr == NULL)) {
2833 dev = packet_cached_dev_get(po);
2834 proto = po->num;
2835 addr = NULL;
2836 } else {
2837 err = -EINVAL;
2838 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2839 goto out;
2840 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2841 goto out;
2842 proto = saddr->sll_protocol;
2843 addr = saddr->sll_addr;
2844 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2845 }
2846
2847 err = -ENXIO;
2848 if (unlikely(dev == NULL))
2849 goto out_unlock;
2850 err = -ENETDOWN;
2851 if (unlikely(!(dev->flags & IFF_UP)))
2852 goto out_unlock;
2853
2854 sockc.mark = sk->sk_mark;
2855 if (msg->msg_controllen) {
2856 err = sock_cmsg_send(sk, msg, &sockc);
2857 if (unlikely(err))
2858 goto out_unlock;
2859 }
2860
2861 if (sock->type == SOCK_RAW)
2862 reserve = dev->hard_header_len;
2863 if (po->has_vnet_hdr) {
2864 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2865 if (err)
2866 goto out_unlock;
2867 }
2868
2869 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2870 if (!netif_supports_nofcs(dev)) {
2871 err = -EPROTONOSUPPORT;
2872 goto out_unlock;
2873 }
2874 extra_len = 4; /* We're doing our own CRC */
2875 }
2876
2877 err = -EMSGSIZE;
2878 if (!vnet_hdr.gso_type &&
2879 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2880 goto out_unlock;
2881
2882 err = -ENOBUFS;
2883 hlen = LL_RESERVED_SPACE(dev);
2884 tlen = dev->needed_tailroom;
2885 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2886 __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len),
2887 msg->msg_flags & MSG_DONTWAIT, &err);
2888 if (skb == NULL)
2889 goto out_unlock;
2890
2891 skb_set_network_header(skb, reserve);
2892
2893 err = -EINVAL;
2894 if (sock->type == SOCK_DGRAM) {
2895 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2896 if (unlikely(offset < 0))
2897 goto out_free;
2898 }
2899
2900 /* Returns -EFAULT on error */
2901 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2902 if (err)
2903 goto out_free;
2904
2905 if (sock->type == SOCK_RAW &&
2906 !dev_validate_header(dev, skb->data, len)) {
2907 err = -EINVAL;
2908 goto out_free;
2909 }
2910
2911 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2912
2913 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2914 !packet_extra_vlan_len_allowed(dev, skb)) {
2915 err = -EMSGSIZE;
2916 goto out_free;
2917 }
2918
2919 skb->protocol = proto;
2920 skb->dev = dev;
2921 skb->priority = sk->sk_priority;
2922 skb->mark = sockc.mark;
2923
2924 packet_pick_tx_queue(dev, skb);
2925
2926 if (po->has_vnet_hdr) {
2927 err = packet_snd_vnet_gso(skb, &vnet_hdr);
2928 if (err)
2929 goto out_free;
2930 len += sizeof(vnet_hdr);
2931 }
2932
2933 skb_probe_transport_header(skb, reserve);
2934
2935 if (unlikely(extra_len == 4))
2936 skb->no_fcs = 1;
2937
2938 err = po->xmit(skb);
2939 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2940 goto out_unlock;
2941
2942 dev_put(dev);
2943
2944 return len;
2945
2946out_free:
2947 kfree_skb(skb);
2948out_unlock:
2949 if (dev)
2950 dev_put(dev);
2951out:
2952 return err;
2953}
2954
2955static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2956{
2957 struct sock *sk = sock->sk;
2958 struct packet_sock *po = pkt_sk(sk);
2959
2960 if (po->tx_ring.pg_vec)
2961 return tpacket_snd(po, msg);
2962 else
2963 return packet_snd(sock, msg, len);
2964}
2965
2966/*
2967 * Close a PACKET socket. This is fairly simple. We immediately go
2968 * to 'closed' state and remove our protocol entry in the device list.
2969 */
2970
2971static int packet_release(struct socket *sock)
2972{
2973 struct sock *sk = sock->sk;
2974 struct packet_sock *po;
2975 struct net *net;
2976 union tpacket_req_u req_u;
2977
2978 if (!sk)
2979 return 0;
2980
2981 net = sock_net(sk);
2982 po = pkt_sk(sk);
2983
2984 mutex_lock(&net->packet.sklist_lock);
2985 sk_del_node_init_rcu(sk);
2986 mutex_unlock(&net->packet.sklist_lock);
2987
2988 preempt_disable();
2989 sock_prot_inuse_add(net, sk->sk_prot, -1);
2990 preempt_enable();
2991
2992 spin_lock(&po->bind_lock);
2993 unregister_prot_hook(sk, false);
2994 packet_cached_dev_reset(po);
2995
2996 if (po->prot_hook.dev) {
2997 dev_put(po->prot_hook.dev);
2998 po->prot_hook.dev = NULL;
2999 }
3000 spin_unlock(&po->bind_lock);
3001
3002 packet_flush_mclist(sk);
3003
3004 if (po->rx_ring.pg_vec) {
3005 memset(&req_u, 0, sizeof(req_u));
3006 packet_set_ring(sk, &req_u, 1, 0);
3007 }
3008
3009 if (po->tx_ring.pg_vec) {
3010 memset(&req_u, 0, sizeof(req_u));
3011 packet_set_ring(sk, &req_u, 1, 1);
3012 }
3013
3014 fanout_release(sk);
3015
3016 synchronize_net();
3017 /*
3018 * Now the socket is dead. No more input will appear.
3019 */
3020 sock_orphan(sk);
3021 sock->sk = NULL;
3022
3023 /* Purge queues */
3024
3025 skb_queue_purge(&sk->sk_receive_queue);
3026 packet_free_pending(po);
3027 sk_refcnt_debug_release(sk);
3028
3029 sock_put(sk);
3030 return 0;
3031}
3032
3033/*
3034 * Attach a packet hook.
3035 */
3036
3037static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3038 __be16 proto)
3039{
3040 struct packet_sock *po = pkt_sk(sk);
3041 struct net_device *dev_curr;
3042 __be16 proto_curr;
3043 bool need_rehook;
3044 struct net_device *dev = NULL;
3045 int ret = 0;
3046 bool unlisted = false;
3047
3048 if (po->fanout)
3049 return -EINVAL;
3050
3051 lock_sock(sk);
3052 spin_lock(&po->bind_lock);
3053 rcu_read_lock();
3054
3055 if (name) {
3056 dev = dev_get_by_name_rcu(sock_net(sk), name);
3057 if (!dev) {
3058 ret = -ENODEV;
3059 goto out_unlock;
3060 }
3061 } else if (ifindex) {
3062 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3063 if (!dev) {
3064 ret = -ENODEV;
3065 goto out_unlock;
3066 }
3067 }
3068
3069 if (dev)
3070 dev_hold(dev);
3071
3072 proto_curr = po->prot_hook.type;
3073 dev_curr = po->prot_hook.dev;
3074
3075 need_rehook = proto_curr != proto || dev_curr != dev;
3076
3077 if (need_rehook) {
3078 if (po->running) {
3079 rcu_read_unlock();
3080 __unregister_prot_hook(sk, true);
3081 rcu_read_lock();
3082 dev_curr = po->prot_hook.dev;
3083 if (dev)
3084 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3085 dev->ifindex);
3086 }
3087
3088 po->num = proto;
3089 po->prot_hook.type = proto;
3090
3091 if (unlikely(unlisted)) {
3092 dev_put(dev);
3093 po->prot_hook.dev = NULL;
3094 po->ifindex = -1;
3095 packet_cached_dev_reset(po);
3096 } else {
3097 po->prot_hook.dev = dev;
3098 po->ifindex = dev ? dev->ifindex : 0;
3099 packet_cached_dev_assign(po, dev);
3100 }
3101 }
3102 if (dev_curr)
3103 dev_put(dev_curr);
3104
3105 if (proto == 0 || !need_rehook)
3106 goto out_unlock;
3107
3108 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3109 register_prot_hook(sk);
3110 } else {
3111 sk->sk_err = ENETDOWN;
3112 if (!sock_flag(sk, SOCK_DEAD))
3113 sk->sk_error_report(sk);
3114 }
3115
3116out_unlock:
3117 rcu_read_unlock();
3118 spin_unlock(&po->bind_lock);
3119 release_sock(sk);
3120 return ret;
3121}
3122
3123/*
3124 * Bind a packet socket to a device
3125 */
3126
3127static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3128 int addr_len)
3129{
3130 struct sock *sk = sock->sk;
3131 char name[15];
3132
3133 /*
3134 * Check legality
3135 */
3136
3137 if (addr_len != sizeof(struct sockaddr))
3138 return -EINVAL;
3139 strlcpy(name, uaddr->sa_data, sizeof(name));
3140
3141 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3142}
3143
3144static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3145{
3146 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3147 struct sock *sk = sock->sk;
3148
3149 /*
3150 * Check legality
3151 */
3152
3153 if (addr_len < sizeof(struct sockaddr_ll))
3154 return -EINVAL;
3155 if (sll->sll_family != AF_PACKET)
3156 return -EINVAL;
3157
3158 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3159 sll->sll_protocol ? : pkt_sk(sk)->num);
3160}
3161
3162static struct proto packet_proto = {
3163 .name = "PACKET",
3164 .owner = THIS_MODULE,
3165 .obj_size = sizeof(struct packet_sock),
3166};
3167
3168/*
3169 * Create a packet of type SOCK_PACKET.
3170 */
3171
3172static int packet_create(struct net *net, struct socket *sock, int protocol,
3173 int kern)
3174{
3175 struct sock *sk;
3176 struct packet_sock *po;
3177 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3178 int err;
3179
3180 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3181 return -EPERM;
3182 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3183 sock->type != SOCK_PACKET)
3184 return -ESOCKTNOSUPPORT;
3185
3186 sock->state = SS_UNCONNECTED;
3187
3188 err = -ENOBUFS;
3189 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3190 if (sk == NULL)
3191 goto out;
3192
3193 sock->ops = &packet_ops;
3194 if (sock->type == SOCK_PACKET)
3195 sock->ops = &packet_ops_spkt;
3196
3197 sock_init_data(sock, sk);
3198
3199 po = pkt_sk(sk);
3200 sk->sk_family = PF_PACKET;
3201 po->num = proto;
3202 po->xmit = dev_queue_xmit;
3203
3204 err = packet_alloc_pending(po);
3205 if (err)
3206 goto out2;
3207
3208 packet_cached_dev_reset(po);
3209
3210 sk->sk_destruct = packet_sock_destruct;
3211 sk_refcnt_debug_inc(sk);
3212
3213 /*
3214 * Attach a protocol block
3215 */
3216
3217 spin_lock_init(&po->bind_lock);
3218 mutex_init(&po->pg_vec_lock);
3219 po->rollover = NULL;
3220 po->prot_hook.func = packet_rcv;
3221
3222 if (sock->type == SOCK_PACKET)
3223 po->prot_hook.func = packet_rcv_spkt;
3224
3225 po->prot_hook.af_packet_priv = sk;
3226
3227 if (proto) {
3228 po->prot_hook.type = proto;
3229 register_prot_hook(sk);
3230 }
3231
3232 mutex_lock(&net->packet.sklist_lock);
3233 sk_add_node_rcu(sk, &net->packet.sklist);
3234 mutex_unlock(&net->packet.sklist_lock);
3235
3236 preempt_disable();
3237 sock_prot_inuse_add(net, &packet_proto, 1);
3238 preempt_enable();
3239
3240 return 0;
3241out2:
3242 sk_free(sk);
3243out:
3244 return err;
3245}
3246
3247/*
3248 * Pull a packet from our receive queue and hand it to the user.
3249 * If necessary we block.
3250 */
3251
3252static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3253 int flags)
3254{
3255 struct sock *sk = sock->sk;
3256 struct sk_buff *skb;
3257 int copied, err;
3258 int vnet_hdr_len = 0;
3259 unsigned int origlen = 0;
3260
3261 err = -EINVAL;
3262 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3263 goto out;
3264
3265#if 0
3266 /* What error should we return now? EUNATTACH? */
3267 if (pkt_sk(sk)->ifindex < 0)
3268 return -ENODEV;
3269#endif
3270
3271 if (flags & MSG_ERRQUEUE) {
3272 err = sock_recv_errqueue(sk, msg, len,
3273 SOL_PACKET, PACKET_TX_TIMESTAMP);
3274 goto out;
3275 }
3276
3277 /*
3278 * Call the generic datagram receiver. This handles all sorts
3279 * of horrible races and re-entrancy so we can forget about it
3280 * in the protocol layers.
3281 *
3282 * Now it will return ENETDOWN, if device have just gone down,
3283 * but then it will block.
3284 */
3285
3286 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3287
3288 /*
3289 * An error occurred so return it. Because skb_recv_datagram()
3290 * handles the blocking we don't see and worry about blocking
3291 * retries.
3292 */
3293
3294 if (skb == NULL)
3295 goto out;
3296
3297 if (pkt_sk(sk)->pressure)
3298 packet_rcv_has_room(pkt_sk(sk), NULL);
3299
3300 if (pkt_sk(sk)->has_vnet_hdr) {
3301 err = packet_rcv_vnet(msg, skb, &len);
3302 if (err)
3303 goto out_free;
3304 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3305 }
3306
3307 /* You lose any data beyond the buffer you gave. If it worries
3308 * a user program they can ask the device for its MTU
3309 * anyway.
3310 */
3311 copied = skb->len;
3312 if (copied > len) {
3313 copied = len;
3314 msg->msg_flags |= MSG_TRUNC;
3315 }
3316
3317 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3318 if (err)
3319 goto out_free;
3320
3321 if (sock->type != SOCK_PACKET) {
3322 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3323
3324 /* Original length was stored in sockaddr_ll fields */
3325 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3326 sll->sll_family = AF_PACKET;
3327 sll->sll_protocol = skb->protocol;
3328 }
3329
3330 sock_recv_ts_and_drops(msg, sk, skb);
3331
3332 if (msg->msg_name) {
3333 /* If the address length field is there to be filled
3334 * in, we fill it in now.
3335 */
3336 if (sock->type == SOCK_PACKET) {
3337 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3338 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3339 } else {
3340 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3341
3342 msg->msg_namelen = sll->sll_halen +
3343 offsetof(struct sockaddr_ll, sll_addr);
3344 }
3345 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3346 msg->msg_namelen);
3347 }
3348
3349 if (pkt_sk(sk)->auxdata) {
3350 struct tpacket_auxdata aux;
3351
3352 aux.tp_status = TP_STATUS_USER;
3353 if (skb->ip_summed == CHECKSUM_PARTIAL)
3354 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3355 else if (skb->pkt_type != PACKET_OUTGOING &&
3356 (skb->ip_summed == CHECKSUM_COMPLETE ||
3357 skb_csum_unnecessary(skb)))
3358 aux.tp_status |= TP_STATUS_CSUM_VALID;
3359
3360 aux.tp_len = origlen;
3361 aux.tp_snaplen = skb->len;
3362 aux.tp_mac = 0;
3363 aux.tp_net = skb_network_offset(skb);
3364 if (skb_vlan_tag_present(skb)) {
3365 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3366 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3367 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3368 } else {
3369 aux.tp_vlan_tci = 0;
3370 aux.tp_vlan_tpid = 0;
3371 }
3372 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3373 }
3374
3375 /*
3376 * Free or return the buffer as appropriate. Again this
3377 * hides all the races and re-entrancy issues from us.
3378 */
3379 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3380
3381out_free:
3382 skb_free_datagram(sk, skb);
3383out:
3384 return err;
3385}
3386
3387static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3388 int *uaddr_len, int peer)
3389{
3390 struct net_device *dev;
3391 struct sock *sk = sock->sk;
3392
3393 if (peer)
3394 return -EOPNOTSUPP;
3395
3396 uaddr->sa_family = AF_PACKET;
3397 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3398 rcu_read_lock();
3399 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3400 if (dev)
3401 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3402 rcu_read_unlock();
3403 *uaddr_len = sizeof(*uaddr);
3404
3405 return 0;
3406}
3407
3408static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3409 int *uaddr_len, int peer)
3410{
3411 struct net_device *dev;
3412 struct sock *sk = sock->sk;
3413 struct packet_sock *po = pkt_sk(sk);
3414 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3415
3416 if (peer)
3417 return -EOPNOTSUPP;
3418
3419 sll->sll_family = AF_PACKET;
3420 sll->sll_ifindex = po->ifindex;
3421 sll->sll_protocol = po->num;
3422 sll->sll_pkttype = 0;
3423 rcu_read_lock();
3424 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3425 if (dev) {
3426 sll->sll_hatype = dev->type;
3427 sll->sll_halen = dev->addr_len;
3428 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3429 } else {
3430 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3431 sll->sll_halen = 0;
3432 }
3433 rcu_read_unlock();
3434 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3435
3436 return 0;
3437}
3438
3439static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3440 int what)
3441{
3442 switch (i->type) {
3443 case PACKET_MR_MULTICAST:
3444 if (i->alen != dev->addr_len)
3445 return -EINVAL;
3446 if (what > 0)
3447 return dev_mc_add(dev, i->addr);
3448 else
3449 return dev_mc_del(dev, i->addr);
3450 break;
3451 case PACKET_MR_PROMISC:
3452 return dev_set_promiscuity(dev, what);
3453 case PACKET_MR_ALLMULTI:
3454 return dev_set_allmulti(dev, what);
3455 case PACKET_MR_UNICAST:
3456 if (i->alen != dev->addr_len)
3457 return -EINVAL;
3458 if (what > 0)
3459 return dev_uc_add(dev, i->addr);
3460 else
3461 return dev_uc_del(dev, i->addr);
3462 break;
3463 default:
3464 break;
3465 }
3466 return 0;
3467}
3468
3469static void packet_dev_mclist_delete(struct net_device *dev,
3470 struct packet_mclist **mlp)
3471{
3472 struct packet_mclist *ml;
3473
3474 while ((ml = *mlp) != NULL) {
3475 if (ml->ifindex == dev->ifindex) {
3476 packet_dev_mc(dev, ml, -1);
3477 *mlp = ml->next;
3478 kfree(ml);
3479 } else
3480 mlp = &ml->next;
3481 }
3482}
3483
3484static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3485{
3486 struct packet_sock *po = pkt_sk(sk);
3487 struct packet_mclist *ml, *i;
3488 struct net_device *dev;
3489 int err;
3490
3491 rtnl_lock();
3492
3493 err = -ENODEV;
3494 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3495 if (!dev)
3496 goto done;
3497
3498 err = -EINVAL;
3499 if (mreq->mr_alen > dev->addr_len)
3500 goto done;
3501
3502 err = -ENOBUFS;
3503 i = kmalloc(sizeof(*i), GFP_KERNEL);
3504 if (i == NULL)
3505 goto done;
3506
3507 err = 0;
3508 for (ml = po->mclist; ml; ml = ml->next) {
3509 if (ml->ifindex == mreq->mr_ifindex &&
3510 ml->type == mreq->mr_type &&
3511 ml->alen == mreq->mr_alen &&
3512 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3513 ml->count++;
3514 /* Free the new element ... */
3515 kfree(i);
3516 goto done;
3517 }
3518 }
3519
3520 i->type = mreq->mr_type;
3521 i->ifindex = mreq->mr_ifindex;
3522 i->alen = mreq->mr_alen;
3523 memcpy(i->addr, mreq->mr_address, i->alen);
3524 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3525 i->count = 1;
3526 i->next = po->mclist;
3527 po->mclist = i;
3528 err = packet_dev_mc(dev, i, 1);
3529 if (err) {
3530 po->mclist = i->next;
3531 kfree(i);
3532 }
3533
3534done:
3535 rtnl_unlock();
3536 return err;
3537}
3538
3539static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3540{
3541 struct packet_mclist *ml, **mlp;
3542
3543 rtnl_lock();
3544
3545 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3546 if (ml->ifindex == mreq->mr_ifindex &&
3547 ml->type == mreq->mr_type &&
3548 ml->alen == mreq->mr_alen &&
3549 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3550 if (--ml->count == 0) {
3551 struct net_device *dev;
3552 *mlp = ml->next;
3553 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3554 if (dev)
3555 packet_dev_mc(dev, ml, -1);
3556 kfree(ml);
3557 }
3558 break;
3559 }
3560 }
3561 rtnl_unlock();
3562 return 0;
3563}
3564
3565static void packet_flush_mclist(struct sock *sk)
3566{
3567 struct packet_sock *po = pkt_sk(sk);
3568 struct packet_mclist *ml;
3569
3570 if (!po->mclist)
3571 return;
3572
3573 rtnl_lock();
3574 while ((ml = po->mclist) != NULL) {
3575 struct net_device *dev;
3576
3577 po->mclist = ml->next;
3578 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3579 if (dev != NULL)
3580 packet_dev_mc(dev, ml, -1);
3581 kfree(ml);
3582 }
3583 rtnl_unlock();
3584}
3585
3586static int
3587packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3588{
3589 struct sock *sk = sock->sk;
3590 struct packet_sock *po = pkt_sk(sk);
3591 int ret;
3592
3593 if (level != SOL_PACKET)
3594 return -ENOPROTOOPT;
3595
3596 switch (optname) {
3597 case PACKET_ADD_MEMBERSHIP:
3598 case PACKET_DROP_MEMBERSHIP:
3599 {
3600 struct packet_mreq_max mreq;
3601 int len = optlen;
3602 memset(&mreq, 0, sizeof(mreq));
3603 if (len < sizeof(struct packet_mreq))
3604 return -EINVAL;
3605 if (len > sizeof(mreq))
3606 len = sizeof(mreq);
3607 if (copy_from_user(&mreq, optval, len))
3608 return -EFAULT;
3609 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3610 return -EINVAL;
3611 if (optname == PACKET_ADD_MEMBERSHIP)
3612 ret = packet_mc_add(sk, &mreq);
3613 else
3614 ret = packet_mc_drop(sk, &mreq);
3615 return ret;
3616 }
3617
3618 case PACKET_RX_RING:
3619 case PACKET_TX_RING:
3620 {
3621 union tpacket_req_u req_u;
3622 int len;
3623
3624 switch (po->tp_version) {
3625 case TPACKET_V1:
3626 case TPACKET_V2:
3627 len = sizeof(req_u.req);
3628 break;
3629 case TPACKET_V3:
3630 default:
3631 len = sizeof(req_u.req3);
3632 break;
3633 }
3634 if (optlen < len)
3635 return -EINVAL;
3636 if (copy_from_user(&req_u.req, optval, len))
3637 return -EFAULT;
3638 return packet_set_ring(sk, &req_u, 0,
3639 optname == PACKET_TX_RING);
3640 }
3641 case PACKET_COPY_THRESH:
3642 {
3643 int val;
3644
3645 if (optlen != sizeof(val))
3646 return -EINVAL;
3647 if (copy_from_user(&val, optval, sizeof(val)))
3648 return -EFAULT;
3649
3650 pkt_sk(sk)->copy_thresh = val;
3651 return 0;
3652 }
3653 case PACKET_VERSION:
3654 {
3655 int val;
3656
3657 if (optlen != sizeof(val))
3658 return -EINVAL;
3659 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3660 return -EBUSY;
3661 if (copy_from_user(&val, optval, sizeof(val)))
3662 return -EFAULT;
3663 switch (val) {
3664 case TPACKET_V1:
3665 case TPACKET_V2:
3666 case TPACKET_V3:
3667 po->tp_version = val;
3668 return 0;
3669 default:
3670 return -EINVAL;
3671 }
3672 }
3673 case PACKET_RESERVE:
3674 {
3675 unsigned int val;
3676
3677 if (optlen != sizeof(val))
3678 return -EINVAL;
3679 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3680 return -EBUSY;
3681 if (copy_from_user(&val, optval, sizeof(val)))
3682 return -EFAULT;
3683 po->tp_reserve = val;
3684 return 0;
3685 }
3686 case PACKET_LOSS:
3687 {
3688 unsigned int val;
3689
3690 if (optlen != sizeof(val))
3691 return -EINVAL;
3692 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3693 return -EBUSY;
3694 if (copy_from_user(&val, optval, sizeof(val)))
3695 return -EFAULT;
3696 po->tp_loss = !!val;
3697 return 0;
3698 }
3699 case PACKET_AUXDATA:
3700 {
3701 int val;
3702
3703 if (optlen < sizeof(val))
3704 return -EINVAL;
3705 if (copy_from_user(&val, optval, sizeof(val)))
3706 return -EFAULT;
3707
3708 po->auxdata = !!val;
3709 return 0;
3710 }
3711 case PACKET_ORIGDEV:
3712 {
3713 int val;
3714
3715 if (optlen < sizeof(val))
3716 return -EINVAL;
3717 if (copy_from_user(&val, optval, sizeof(val)))
3718 return -EFAULT;
3719
3720 po->origdev = !!val;
3721 return 0;
3722 }
3723 case PACKET_VNET_HDR:
3724 {
3725 int val;
3726
3727 if (sock->type != SOCK_RAW)
3728 return -EINVAL;
3729 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3730 return -EBUSY;
3731 if (optlen < sizeof(val))
3732 return -EINVAL;
3733 if (copy_from_user(&val, optval, sizeof(val)))
3734 return -EFAULT;
3735
3736 po->has_vnet_hdr = !!val;
3737 return 0;
3738 }
3739 case PACKET_TIMESTAMP:
3740 {
3741 int val;
3742
3743 if (optlen != sizeof(val))
3744 return -EINVAL;
3745 if (copy_from_user(&val, optval, sizeof(val)))
3746 return -EFAULT;
3747
3748 po->tp_tstamp = val;
3749 return 0;
3750 }
3751 case PACKET_FANOUT:
3752 {
3753 int val;
3754
3755 if (optlen != sizeof(val))
3756 return -EINVAL;
3757 if (copy_from_user(&val, optval, sizeof(val)))
3758 return -EFAULT;
3759
3760 return fanout_add(sk, val & 0xffff, val >> 16);
3761 }
3762 case PACKET_FANOUT_DATA:
3763 {
3764 if (!po->fanout)
3765 return -EINVAL;
3766
3767 return fanout_set_data(po, optval, optlen);
3768 }
3769 case PACKET_TX_HAS_OFF:
3770 {
3771 unsigned int val;
3772
3773 if (optlen != sizeof(val))
3774 return -EINVAL;
3775 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3776 return -EBUSY;
3777 if (copy_from_user(&val, optval, sizeof(val)))
3778 return -EFAULT;
3779 po->tp_tx_has_off = !!val;
3780 return 0;
3781 }
3782 case PACKET_QDISC_BYPASS:
3783 {
3784 int val;
3785
3786 if (optlen != sizeof(val))
3787 return -EINVAL;
3788 if (copy_from_user(&val, optval, sizeof(val)))
3789 return -EFAULT;
3790
3791 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3792 return 0;
3793 }
3794 default:
3795 return -ENOPROTOOPT;
3796 }
3797}
3798
3799static int packet_getsockopt(struct socket *sock, int level, int optname,
3800 char __user *optval, int __user *optlen)
3801{
3802 int len;
3803 int val, lv = sizeof(val);
3804 struct sock *sk = sock->sk;
3805 struct packet_sock *po = pkt_sk(sk);
3806 void *data = &val;
3807 union tpacket_stats_u st;
3808 struct tpacket_rollover_stats rstats;
3809
3810 if (level != SOL_PACKET)
3811 return -ENOPROTOOPT;
3812
3813 if (get_user(len, optlen))
3814 return -EFAULT;
3815
3816 if (len < 0)
3817 return -EINVAL;
3818
3819 switch (optname) {
3820 case PACKET_STATISTICS:
3821 spin_lock_bh(&sk->sk_receive_queue.lock);
3822 memcpy(&st, &po->stats, sizeof(st));
3823 memset(&po->stats, 0, sizeof(po->stats));
3824 spin_unlock_bh(&sk->sk_receive_queue.lock);
3825
3826 if (po->tp_version == TPACKET_V3) {
3827 lv = sizeof(struct tpacket_stats_v3);
3828 st.stats3.tp_packets += st.stats3.tp_drops;
3829 data = &st.stats3;
3830 } else {
3831 lv = sizeof(struct tpacket_stats);
3832 st.stats1.tp_packets += st.stats1.tp_drops;
3833 data = &st.stats1;
3834 }
3835
3836 break;
3837 case PACKET_AUXDATA:
3838 val = po->auxdata;
3839 break;
3840 case PACKET_ORIGDEV:
3841 val = po->origdev;
3842 break;
3843 case PACKET_VNET_HDR:
3844 val = po->has_vnet_hdr;
3845 break;
3846 case PACKET_VERSION:
3847 val = po->tp_version;
3848 break;
3849 case PACKET_HDRLEN:
3850 if (len > sizeof(int))
3851 len = sizeof(int);
3852 if (copy_from_user(&val, optval, len))
3853 return -EFAULT;
3854 switch (val) {
3855 case TPACKET_V1:
3856 val = sizeof(struct tpacket_hdr);
3857 break;
3858 case TPACKET_V2:
3859 val = sizeof(struct tpacket2_hdr);
3860 break;
3861 case TPACKET_V3:
3862 val = sizeof(struct tpacket3_hdr);
3863 break;
3864 default:
3865 return -EINVAL;
3866 }
3867 break;
3868 case PACKET_RESERVE:
3869 val = po->tp_reserve;
3870 break;
3871 case PACKET_LOSS:
3872 val = po->tp_loss;
3873 break;
3874 case PACKET_TIMESTAMP:
3875 val = po->tp_tstamp;
3876 break;
3877 case PACKET_FANOUT:
3878 val = (po->fanout ?
3879 ((u32)po->fanout->id |
3880 ((u32)po->fanout->type << 16) |
3881 ((u32)po->fanout->flags << 24)) :
3882 0);
3883 break;
3884 case PACKET_ROLLOVER_STATS:
3885 if (!po->rollover)
3886 return -EINVAL;
3887 rstats.tp_all = atomic_long_read(&po->rollover->num);
3888 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3889 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3890 data = &rstats;
3891 lv = sizeof(rstats);
3892 break;
3893 case PACKET_TX_HAS_OFF:
3894 val = po->tp_tx_has_off;
3895 break;
3896 case PACKET_QDISC_BYPASS:
3897 val = packet_use_direct_xmit(po);
3898 break;
3899 default:
3900 return -ENOPROTOOPT;
3901 }
3902
3903 if (len > lv)
3904 len = lv;
3905 if (put_user(len, optlen))
3906 return -EFAULT;
3907 if (copy_to_user(optval, data, len))
3908 return -EFAULT;
3909 return 0;
3910}
3911
3912
3913static int packet_notifier(struct notifier_block *this,
3914 unsigned long msg, void *ptr)
3915{
3916 struct sock *sk;
3917 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3918 struct net *net = dev_net(dev);
3919
3920 rcu_read_lock();
3921 sk_for_each_rcu(sk, &net->packet.sklist) {
3922 struct packet_sock *po = pkt_sk(sk);
3923
3924 switch (msg) {
3925 case NETDEV_UNREGISTER:
3926 if (po->mclist)
3927 packet_dev_mclist_delete(dev, &po->mclist);
3928 /* fallthrough */
3929
3930 case NETDEV_DOWN:
3931 if (dev->ifindex == po->ifindex) {
3932 spin_lock(&po->bind_lock);
3933 if (po->running) {
3934 __unregister_prot_hook(sk, false);
3935 sk->sk_err = ENETDOWN;
3936 if (!sock_flag(sk, SOCK_DEAD))
3937 sk->sk_error_report(sk);
3938 }
3939 if (msg == NETDEV_UNREGISTER) {
3940 packet_cached_dev_reset(po);
3941 po->ifindex = -1;
3942 if (po->prot_hook.dev)
3943 dev_put(po->prot_hook.dev);
3944 po->prot_hook.dev = NULL;
3945 }
3946 spin_unlock(&po->bind_lock);
3947 }
3948 break;
3949 case NETDEV_UP:
3950 if (dev->ifindex == po->ifindex) {
3951 spin_lock(&po->bind_lock);
3952 if (po->num)
3953 register_prot_hook(sk);
3954 spin_unlock(&po->bind_lock);
3955 }
3956 break;
3957 }
3958 }
3959 rcu_read_unlock();
3960 return NOTIFY_DONE;
3961}
3962
3963
3964static int packet_ioctl(struct socket *sock, unsigned int cmd,
3965 unsigned long arg)
3966{
3967 struct sock *sk = sock->sk;
3968
3969 switch (cmd) {
3970 case SIOCOUTQ:
3971 {
3972 int amount = sk_wmem_alloc_get(sk);
3973
3974 return put_user(amount, (int __user *)arg);
3975 }
3976 case SIOCINQ:
3977 {
3978 struct sk_buff *skb;
3979 int amount = 0;
3980
3981 spin_lock_bh(&sk->sk_receive_queue.lock);
3982 skb = skb_peek(&sk->sk_receive_queue);
3983 if (skb)
3984 amount = skb->len;
3985 spin_unlock_bh(&sk->sk_receive_queue.lock);
3986 return put_user(amount, (int __user *)arg);
3987 }
3988 case SIOCGSTAMP:
3989 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3990 case SIOCGSTAMPNS:
3991 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3992
3993#ifdef CONFIG_INET
3994 case SIOCADDRT:
3995 case SIOCDELRT:
3996 case SIOCDARP:
3997 case SIOCGARP:
3998 case SIOCSARP:
3999 case SIOCGIFADDR:
4000 case SIOCSIFADDR:
4001 case SIOCGIFBRDADDR:
4002 case SIOCSIFBRDADDR:
4003 case SIOCGIFNETMASK:
4004 case SIOCSIFNETMASK:
4005 case SIOCGIFDSTADDR:
4006 case SIOCSIFDSTADDR:
4007 case SIOCSIFFLAGS:
4008 return inet_dgram_ops.ioctl(sock, cmd, arg);
4009#endif
4010
4011 default:
4012 return -ENOIOCTLCMD;
4013 }
4014 return 0;
4015}
4016
4017static unsigned int packet_poll(struct file *file, struct socket *sock,
4018 poll_table *wait)
4019{
4020 struct sock *sk = sock->sk;
4021 struct packet_sock *po = pkt_sk(sk);
4022 unsigned int mask = datagram_poll(file, sock, wait);
4023
4024 spin_lock_bh(&sk->sk_receive_queue.lock);
4025 if (po->rx_ring.pg_vec) {
4026 if (!packet_previous_rx_frame(po, &po->rx_ring,
4027 TP_STATUS_KERNEL))
4028 mask |= POLLIN | POLLRDNORM;
4029 }
4030 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
4031 po->pressure = 0;
4032 spin_unlock_bh(&sk->sk_receive_queue.lock);
4033 spin_lock_bh(&sk->sk_write_queue.lock);
4034 if (po->tx_ring.pg_vec) {
4035 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4036 mask |= POLLOUT | POLLWRNORM;
4037 }
4038 spin_unlock_bh(&sk->sk_write_queue.lock);
4039 return mask;
4040}
4041
4042
4043/* Dirty? Well, I still did not learn better way to account
4044 * for user mmaps.
4045 */
4046
4047static void packet_mm_open(struct vm_area_struct *vma)
4048{
4049 struct file *file = vma->vm_file;
4050 struct socket *sock = file->private_data;
4051 struct sock *sk = sock->sk;
4052
4053 if (sk)
4054 atomic_inc(&pkt_sk(sk)->mapped);
4055}
4056
4057static void packet_mm_close(struct vm_area_struct *vma)
4058{
4059 struct file *file = vma->vm_file;
4060 struct socket *sock = file->private_data;
4061 struct sock *sk = sock->sk;
4062
4063 if (sk)
4064 atomic_dec(&pkt_sk(sk)->mapped);
4065}
4066
4067static const struct vm_operations_struct packet_mmap_ops = {
4068 .open = packet_mm_open,
4069 .close = packet_mm_close,
4070};
4071
4072static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4073 unsigned int len)
4074{
4075 int i;
4076
4077 for (i = 0; i < len; i++) {
4078 if (likely(pg_vec[i].buffer)) {
4079 if (is_vmalloc_addr(pg_vec[i].buffer))
4080 vfree(pg_vec[i].buffer);
4081 else
4082 free_pages((unsigned long)pg_vec[i].buffer,
4083 order);
4084 pg_vec[i].buffer = NULL;
4085 }
4086 }
4087 kfree(pg_vec);
4088}
4089
4090static char *alloc_one_pg_vec_page(unsigned long order)
4091{
4092 char *buffer;
4093 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4094 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4095
4096 buffer = (char *) __get_free_pages(gfp_flags, order);
4097 if (buffer)
4098 return buffer;
4099
4100 /* __get_free_pages failed, fall back to vmalloc */
4101 buffer = vzalloc((1 << order) * PAGE_SIZE);
4102 if (buffer)
4103 return buffer;
4104
4105 /* vmalloc failed, lets dig into swap here */
4106 gfp_flags &= ~__GFP_NORETRY;
4107 buffer = (char *) __get_free_pages(gfp_flags, order);
4108 if (buffer)
4109 return buffer;
4110
4111 /* complete and utter failure */
4112 return NULL;
4113}
4114
4115static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4116{
4117 unsigned int block_nr = req->tp_block_nr;
4118 struct pgv *pg_vec;
4119 int i;
4120
4121 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4122 if (unlikely(!pg_vec))
4123 goto out;
4124
4125 for (i = 0; i < block_nr; i++) {
4126 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4127 if (unlikely(!pg_vec[i].buffer))
4128 goto out_free_pgvec;
4129 }
4130
4131out:
4132 return pg_vec;
4133
4134out_free_pgvec:
4135 free_pg_vec(pg_vec, order, block_nr);
4136 pg_vec = NULL;
4137 goto out;
4138}
4139
4140static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4141 int closing, int tx_ring)
4142{
4143 struct pgv *pg_vec = NULL;
4144 struct packet_sock *po = pkt_sk(sk);
4145 int was_running, order = 0;
4146 struct packet_ring_buffer *rb;
4147 struct sk_buff_head *rb_queue;
4148 __be16 num;
4149 int err = -EINVAL;
4150 /* Added to avoid minimal code churn */
4151 struct tpacket_req *req = &req_u->req;
4152
4153 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
4154 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
4155 net_warn_ratelimited("Tx-ring is not supported.\n");
4156 goto out;
4157 }
4158
4159 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4160 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4161
4162 err = -EBUSY;
4163 if (!closing) {
4164 if (atomic_read(&po->mapped))
4165 goto out;
4166 if (packet_read_pending(rb))
4167 goto out;
4168 }
4169
4170 if (req->tp_block_nr) {
4171 /* Sanity tests and some calculations */
4172 err = -EBUSY;
4173 if (unlikely(rb->pg_vec))
4174 goto out;
4175
4176 switch (po->tp_version) {
4177 case TPACKET_V1:
4178 po->tp_hdrlen = TPACKET_HDRLEN;
4179 break;
4180 case TPACKET_V2:
4181 po->tp_hdrlen = TPACKET2_HDRLEN;
4182 break;
4183 case TPACKET_V3:
4184 po->tp_hdrlen = TPACKET3_HDRLEN;
4185 break;
4186 }
4187
4188 err = -EINVAL;
4189 if (unlikely((int)req->tp_block_size <= 0))
4190 goto out;
4191 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4192 goto out;
4193 if (po->tp_version >= TPACKET_V3 &&
4194 (int)(req->tp_block_size -
4195 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
4196 goto out;
4197 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
4198 po->tp_reserve))
4199 goto out;
4200 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4201 goto out;
4202
4203 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4204 if (unlikely(rb->frames_per_block == 0))
4205 goto out;
4206 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4207 req->tp_frame_nr))
4208 goto out;
4209
4210 err = -ENOMEM;
4211 order = get_order(req->tp_block_size);
4212 pg_vec = alloc_pg_vec(req, order);
4213 if (unlikely(!pg_vec))
4214 goto out;
4215 switch (po->tp_version) {
4216 case TPACKET_V3:
4217 /* Transmit path is not supported. We checked
4218 * it above but just being paranoid
4219 */
4220 if (!tx_ring)
4221 init_prb_bdqc(po, rb, pg_vec, req_u);
4222 break;
4223 default:
4224 break;
4225 }
4226 }
4227 /* Done */
4228 else {
4229 err = -EINVAL;
4230 if (unlikely(req->tp_frame_nr))
4231 goto out;
4232 }
4233
4234 lock_sock(sk);
4235
4236 /* Detach socket from network */
4237 spin_lock(&po->bind_lock);
4238 was_running = po->running;
4239 num = po->num;
4240 if (was_running) {
4241 po->num = 0;
4242 __unregister_prot_hook(sk, false);
4243 }
4244 spin_unlock(&po->bind_lock);
4245
4246 synchronize_net();
4247
4248 err = -EBUSY;
4249 mutex_lock(&po->pg_vec_lock);
4250 if (closing || atomic_read(&po->mapped) == 0) {
4251 err = 0;
4252 spin_lock_bh(&rb_queue->lock);
4253 swap(rb->pg_vec, pg_vec);
4254 rb->frame_max = (req->tp_frame_nr - 1);
4255 rb->head = 0;
4256 rb->frame_size = req->tp_frame_size;
4257 spin_unlock_bh(&rb_queue->lock);
4258
4259 swap(rb->pg_vec_order, order);
4260 swap(rb->pg_vec_len, req->tp_block_nr);
4261
4262 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4263 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4264 tpacket_rcv : packet_rcv;
4265 skb_queue_purge(rb_queue);
4266 if (atomic_read(&po->mapped))
4267 pr_err("packet_mmap: vma is busy: %d\n",
4268 atomic_read(&po->mapped));
4269 }
4270 mutex_unlock(&po->pg_vec_lock);
4271
4272 spin_lock(&po->bind_lock);
4273 if (was_running) {
4274 po->num = num;
4275 register_prot_hook(sk);
4276 }
4277 spin_unlock(&po->bind_lock);
4278 if (closing && (po->tp_version > TPACKET_V2)) {
4279 /* Because we don't support block-based V3 on tx-ring */
4280 if (!tx_ring)
4281 prb_shutdown_retire_blk_timer(po, rb_queue);
4282 }
4283 release_sock(sk);
4284
4285 if (pg_vec)
4286 free_pg_vec(pg_vec, order, req->tp_block_nr);
4287out:
4288 return err;
4289}
4290
4291static int packet_mmap(struct file *file, struct socket *sock,
4292 struct vm_area_struct *vma)
4293{
4294 struct sock *sk = sock->sk;
4295 struct packet_sock *po = pkt_sk(sk);
4296 unsigned long size, expected_size;
4297 struct packet_ring_buffer *rb;
4298 unsigned long start;
4299 int err = -EINVAL;
4300 int i;
4301
4302 if (vma->vm_pgoff)
4303 return -EINVAL;
4304
4305 mutex_lock(&po->pg_vec_lock);
4306
4307 expected_size = 0;
4308 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4309 if (rb->pg_vec) {
4310 expected_size += rb->pg_vec_len
4311 * rb->pg_vec_pages
4312 * PAGE_SIZE;
4313 }
4314 }
4315
4316 if (expected_size == 0)
4317 goto out;
4318
4319 size = vma->vm_end - vma->vm_start;
4320 if (size != expected_size)
4321 goto out;
4322
4323 start = vma->vm_start;
4324 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4325 if (rb->pg_vec == NULL)
4326 continue;
4327
4328 for (i = 0; i < rb->pg_vec_len; i++) {
4329 struct page *page;
4330 void *kaddr = rb->pg_vec[i].buffer;
4331 int pg_num;
4332
4333 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4334 page = pgv_to_page(kaddr);
4335 err = vm_insert_page(vma, start, page);
4336 if (unlikely(err))
4337 goto out;
4338 start += PAGE_SIZE;
4339 kaddr += PAGE_SIZE;
4340 }
4341 }
4342 }
4343
4344 atomic_inc(&po->mapped);
4345 vma->vm_ops = &packet_mmap_ops;
4346 err = 0;
4347
4348out:
4349 mutex_unlock(&po->pg_vec_lock);
4350 return err;
4351}
4352
4353static const struct proto_ops packet_ops_spkt = {
4354 .family = PF_PACKET,
4355 .owner = THIS_MODULE,
4356 .release = packet_release,
4357 .bind = packet_bind_spkt,
4358 .connect = sock_no_connect,
4359 .socketpair = sock_no_socketpair,
4360 .accept = sock_no_accept,
4361 .getname = packet_getname_spkt,
4362 .poll = datagram_poll,
4363 .ioctl = packet_ioctl,
4364 .listen = sock_no_listen,
4365 .shutdown = sock_no_shutdown,
4366 .setsockopt = sock_no_setsockopt,
4367 .getsockopt = sock_no_getsockopt,
4368 .sendmsg = packet_sendmsg_spkt,
4369 .recvmsg = packet_recvmsg,
4370 .mmap = sock_no_mmap,
4371 .sendpage = sock_no_sendpage,
4372};
4373
4374static const struct proto_ops packet_ops = {
4375 .family = PF_PACKET,
4376 .owner = THIS_MODULE,
4377 .release = packet_release,
4378 .bind = packet_bind,
4379 .connect = sock_no_connect,
4380 .socketpair = sock_no_socketpair,
4381 .accept = sock_no_accept,
4382 .getname = packet_getname,
4383 .poll = packet_poll,
4384 .ioctl = packet_ioctl,
4385 .listen = sock_no_listen,
4386 .shutdown = sock_no_shutdown,
4387 .setsockopt = packet_setsockopt,
4388 .getsockopt = packet_getsockopt,
4389 .sendmsg = packet_sendmsg,
4390 .recvmsg = packet_recvmsg,
4391 .mmap = packet_mmap,
4392 .sendpage = sock_no_sendpage,
4393};
4394
4395static const struct net_proto_family packet_family_ops = {
4396 .family = PF_PACKET,
4397 .create = packet_create,
4398 .owner = THIS_MODULE,
4399};
4400
4401static struct notifier_block packet_netdev_notifier = {
4402 .notifier_call = packet_notifier,
4403};
4404
4405#ifdef CONFIG_PROC_FS
4406
4407static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4408 __acquires(RCU)
4409{
4410 struct net *net = seq_file_net(seq);
4411
4412 rcu_read_lock();
4413 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4414}
4415
4416static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4417{
4418 struct net *net = seq_file_net(seq);
4419 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4420}
4421
4422static void packet_seq_stop(struct seq_file *seq, void *v)
4423 __releases(RCU)
4424{
4425 rcu_read_unlock();
4426}
4427
4428static int packet_seq_show(struct seq_file *seq, void *v)
4429{
4430 if (v == SEQ_START_TOKEN)
4431 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4432 else {
4433 struct sock *s = sk_entry(v);
4434 const struct packet_sock *po = pkt_sk(s);
4435
4436 seq_printf(seq,
4437 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4438 s,
4439 atomic_read(&s->sk_refcnt),
4440 s->sk_type,
4441 ntohs(po->num),
4442 po->ifindex,
4443 po->running,
4444 atomic_read(&s->sk_rmem_alloc),
4445 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4446 sock_i_ino(s));
4447 }
4448
4449 return 0;
4450}
4451
4452static const struct seq_operations packet_seq_ops = {
4453 .start = packet_seq_start,
4454 .next = packet_seq_next,
4455 .stop = packet_seq_stop,
4456 .show = packet_seq_show,
4457};
4458
4459static int packet_seq_open(struct inode *inode, struct file *file)
4460{
4461 return seq_open_net(inode, file, &packet_seq_ops,
4462 sizeof(struct seq_net_private));
4463}
4464
4465static const struct file_operations packet_seq_fops = {
4466 .owner = THIS_MODULE,
4467 .open = packet_seq_open,
4468 .read = seq_read,
4469 .llseek = seq_lseek,
4470 .release = seq_release_net,
4471};
4472
4473#endif
4474
4475static int __net_init packet_net_init(struct net *net)
4476{
4477 mutex_init(&net->packet.sklist_lock);
4478 INIT_HLIST_HEAD(&net->packet.sklist);
4479
4480 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4481 return -ENOMEM;
4482
4483 return 0;
4484}
4485
4486static void __net_exit packet_net_exit(struct net *net)
4487{
4488 remove_proc_entry("packet", net->proc_net);
4489}
4490
4491static struct pernet_operations packet_net_ops = {
4492 .init = packet_net_init,
4493 .exit = packet_net_exit,
4494};
4495
4496
4497static void __exit packet_exit(void)
4498{
4499 unregister_netdevice_notifier(&packet_netdev_notifier);
4500 unregister_pernet_subsys(&packet_net_ops);
4501 sock_unregister(PF_PACKET);
4502 proto_unregister(&packet_proto);
4503}
4504
4505static int __init packet_init(void)
4506{
4507 int rc = proto_register(&packet_proto, 0);
4508
4509 if (rc != 0)
4510 goto out;
4511
4512 sock_register(&packet_family_ops);
4513 register_pernet_subsys(&packet_net_ops);
4514 register_netdevice_notifier(&packet_netdev_notifier);
4515out:
4516 return rc;
4517}
4518
4519module_init(packet_init);
4520module_exit(packet_exit);
4521MODULE_LICENSE("GPL");
4522MODULE_ALIAS_NETPROTO(PF_PACKET);
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 <linux/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/percpu.h>
92#ifdef CONFIG_INET
93#include <net/inet_common.h>
94#endif
95#include <linux/bpf.h>
96#include <net/compat.h>
97
98#include "internal.h"
99
100/*
101 Assumptions:
102 - if device has no dev->hard_header routine, it adds and removes ll header
103 inside itself. In this case ll header is invisible outside of device,
104 but higher levels still should reserve dev->hard_header_len.
105 Some devices are enough clever to reallocate skb, when header
106 will not fit to reserved space (tunnel), another ones are silly
107 (PPP).
108 - packet socket receives packets with pulled ll header,
109 so that SOCK_RAW should push it back.
110
111On receive:
112-----------
113
114Incoming, dev->hard_header!=NULL
115 mac_header -> ll header
116 data -> data
117
118Outgoing, dev->hard_header!=NULL
119 mac_header -> ll header
120 data -> ll header
121
122Incoming, dev->hard_header==NULL
123 mac_header -> UNKNOWN position. It is very likely, that it points to ll
124 header. PPP makes it, that is wrong, because introduce
125 assymetry between rx and tx paths.
126 data -> data
127
128Outgoing, dev->hard_header==NULL
129 mac_header -> data. ll header is still not built!
130 data -> data
131
132Resume
133 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
134
135
136On transmit:
137------------
138
139dev->hard_header != NULL
140 mac_header -> ll header
141 data -> ll header
142
143dev->hard_header == NULL (ll header is added by device, we cannot control it)
144 mac_header -> data
145 data -> data
146
147 We should set nh.raw on output to correct posistion,
148 packet classifier depends on it.
149 */
150
151/* Private packet socket structures. */
152
153/* identical to struct packet_mreq except it has
154 * a longer address field.
155 */
156struct packet_mreq_max {
157 int mr_ifindex;
158 unsigned short mr_type;
159 unsigned short mr_alen;
160 unsigned char mr_address[MAX_ADDR_LEN];
161};
162
163union tpacket_uhdr {
164 struct tpacket_hdr *h1;
165 struct tpacket2_hdr *h2;
166 struct tpacket3_hdr *h3;
167 void *raw;
168};
169
170static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
171 int closing, int tx_ring);
172
173#define V3_ALIGNMENT (8)
174
175#define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
176
177#define BLK_PLUS_PRIV(sz_of_priv) \
178 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
179
180#define PGV_FROM_VMALLOC 1
181
182#define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
183#define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
184#define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
185#define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
186#define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
187#define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
188#define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
189
190struct packet_sock;
191static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
192static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
193 struct packet_type *pt, struct net_device *orig_dev);
194
195static void *packet_previous_frame(struct packet_sock *po,
196 struct packet_ring_buffer *rb,
197 int status);
198static void packet_increment_head(struct packet_ring_buffer *buff);
199static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
200 struct tpacket_block_desc *);
201static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
202 struct packet_sock *);
203static void prb_retire_current_block(struct tpacket_kbdq_core *,
204 struct packet_sock *, unsigned int status);
205static int prb_queue_frozen(struct tpacket_kbdq_core *);
206static void prb_open_block(struct tpacket_kbdq_core *,
207 struct tpacket_block_desc *);
208static void prb_retire_rx_blk_timer_expired(unsigned long);
209static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
210static void prb_init_blk_timer(struct packet_sock *,
211 struct tpacket_kbdq_core *,
212 void (*func) (unsigned long));
213static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
214static void prb_clear_rxhash(struct tpacket_kbdq_core *,
215 struct tpacket3_hdr *);
216static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
217 struct tpacket3_hdr *);
218static void packet_flush_mclist(struct sock *sk);
219
220struct packet_skb_cb {
221 union {
222 struct sockaddr_pkt pkt;
223 union {
224 /* Trick: alias skb original length with
225 * ll.sll_family and ll.protocol in order
226 * to save room.
227 */
228 unsigned int origlen;
229 struct sockaddr_ll ll;
230 };
231 } sa;
232};
233
234#define vio_le() virtio_legacy_is_little_endian()
235
236#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
237
238#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
239#define GET_PBLOCK_DESC(x, bid) \
240 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
241#define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
242 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
243#define GET_NEXT_PRB_BLK_NUM(x) \
244 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
245 ((x)->kactive_blk_num+1) : 0)
246
247static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
248static void __fanout_link(struct sock *sk, struct packet_sock *po);
249
250static int packet_direct_xmit(struct sk_buff *skb)
251{
252 struct net_device *dev = skb->dev;
253 struct sk_buff *orig_skb = skb;
254 struct netdev_queue *txq;
255 int ret = NETDEV_TX_BUSY;
256
257 if (unlikely(!netif_running(dev) ||
258 !netif_carrier_ok(dev)))
259 goto drop;
260
261 skb = validate_xmit_skb_list(skb, dev);
262 if (skb != orig_skb)
263 goto drop;
264
265 txq = skb_get_tx_queue(dev, skb);
266
267 local_bh_disable();
268
269 HARD_TX_LOCK(dev, txq, smp_processor_id());
270 if (!netif_xmit_frozen_or_drv_stopped(txq))
271 ret = netdev_start_xmit(skb, dev, txq, false);
272 HARD_TX_UNLOCK(dev, txq);
273
274 local_bh_enable();
275
276 if (!dev_xmit_complete(ret))
277 kfree_skb(skb);
278
279 return ret;
280drop:
281 atomic_long_inc(&dev->tx_dropped);
282 kfree_skb_list(skb);
283 return NET_XMIT_DROP;
284}
285
286static struct net_device *packet_cached_dev_get(struct packet_sock *po)
287{
288 struct net_device *dev;
289
290 rcu_read_lock();
291 dev = rcu_dereference(po->cached_dev);
292 if (likely(dev))
293 dev_hold(dev);
294 rcu_read_unlock();
295
296 return dev;
297}
298
299static void packet_cached_dev_assign(struct packet_sock *po,
300 struct net_device *dev)
301{
302 rcu_assign_pointer(po->cached_dev, dev);
303}
304
305static void packet_cached_dev_reset(struct packet_sock *po)
306{
307 RCU_INIT_POINTER(po->cached_dev, NULL);
308}
309
310static bool packet_use_direct_xmit(const struct packet_sock *po)
311{
312 return po->xmit == packet_direct_xmit;
313}
314
315static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
316{
317 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
318}
319
320static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
321{
322 const struct net_device_ops *ops = dev->netdev_ops;
323 u16 queue_index;
324
325 if (ops->ndo_select_queue) {
326 queue_index = ops->ndo_select_queue(dev, skb, NULL,
327 __packet_pick_tx_queue);
328 queue_index = netdev_cap_txqueue(dev, queue_index);
329 } else {
330 queue_index = __packet_pick_tx_queue(dev, skb);
331 }
332
333 skb_set_queue_mapping(skb, queue_index);
334}
335
336/* register_prot_hook must be invoked with the po->bind_lock held,
337 * or from a context in which asynchronous accesses to the packet
338 * socket is not possible (packet_create()).
339 */
340static void register_prot_hook(struct sock *sk)
341{
342 struct packet_sock *po = pkt_sk(sk);
343
344 if (!po->running) {
345 if (po->fanout)
346 __fanout_link(sk, po);
347 else
348 dev_add_pack(&po->prot_hook);
349
350 sock_hold(sk);
351 po->running = 1;
352 }
353}
354
355/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
356 * held. If the sync parameter is true, we will temporarily drop
357 * the po->bind_lock and do a synchronize_net to make sure no
358 * asynchronous packet processing paths still refer to the elements
359 * of po->prot_hook. If the sync parameter is false, it is the
360 * callers responsibility to take care of this.
361 */
362static void __unregister_prot_hook(struct sock *sk, bool sync)
363{
364 struct packet_sock *po = pkt_sk(sk);
365
366 po->running = 0;
367
368 if (po->fanout)
369 __fanout_unlink(sk, po);
370 else
371 __dev_remove_pack(&po->prot_hook);
372
373 __sock_put(sk);
374
375 if (sync) {
376 spin_unlock(&po->bind_lock);
377 synchronize_net();
378 spin_lock(&po->bind_lock);
379 }
380}
381
382static void unregister_prot_hook(struct sock *sk, bool sync)
383{
384 struct packet_sock *po = pkt_sk(sk);
385
386 if (po->running)
387 __unregister_prot_hook(sk, sync);
388}
389
390static inline struct page * __pure pgv_to_page(void *addr)
391{
392 if (is_vmalloc_addr(addr))
393 return vmalloc_to_page(addr);
394 return virt_to_page(addr);
395}
396
397static void __packet_set_status(struct packet_sock *po, void *frame, int status)
398{
399 union tpacket_uhdr h;
400
401 h.raw = frame;
402 switch (po->tp_version) {
403 case TPACKET_V1:
404 h.h1->tp_status = status;
405 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
406 break;
407 case TPACKET_V2:
408 h.h2->tp_status = status;
409 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
410 break;
411 case TPACKET_V3:
412 default:
413 WARN(1, "TPACKET version not supported.\n");
414 BUG();
415 }
416
417 smp_wmb();
418}
419
420static int __packet_get_status(struct packet_sock *po, void *frame)
421{
422 union tpacket_uhdr h;
423
424 smp_rmb();
425
426 h.raw = frame;
427 switch (po->tp_version) {
428 case TPACKET_V1:
429 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
430 return h.h1->tp_status;
431 case TPACKET_V2:
432 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
433 return h.h2->tp_status;
434 case TPACKET_V3:
435 default:
436 WARN(1, "TPACKET version not supported.\n");
437 BUG();
438 return 0;
439 }
440}
441
442static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
443 unsigned int flags)
444{
445 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
446
447 if (shhwtstamps &&
448 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
449 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
450 return TP_STATUS_TS_RAW_HARDWARE;
451
452 if (ktime_to_timespec_cond(skb->tstamp, ts))
453 return TP_STATUS_TS_SOFTWARE;
454
455 return 0;
456}
457
458static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
459 struct sk_buff *skb)
460{
461 union tpacket_uhdr h;
462 struct timespec ts;
463 __u32 ts_status;
464
465 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
466 return 0;
467
468 h.raw = frame;
469 switch (po->tp_version) {
470 case TPACKET_V1:
471 h.h1->tp_sec = ts.tv_sec;
472 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
473 break;
474 case TPACKET_V2:
475 h.h2->tp_sec = ts.tv_sec;
476 h.h2->tp_nsec = ts.tv_nsec;
477 break;
478 case TPACKET_V3:
479 default:
480 WARN(1, "TPACKET version not supported.\n");
481 BUG();
482 }
483
484 /* one flush is safe, as both fields always lie on the same cacheline */
485 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
486 smp_wmb();
487
488 return ts_status;
489}
490
491static void *packet_lookup_frame(struct packet_sock *po,
492 struct packet_ring_buffer *rb,
493 unsigned int position,
494 int status)
495{
496 unsigned int pg_vec_pos, frame_offset;
497 union tpacket_uhdr h;
498
499 pg_vec_pos = position / rb->frames_per_block;
500 frame_offset = position % rb->frames_per_block;
501
502 h.raw = rb->pg_vec[pg_vec_pos].buffer +
503 (frame_offset * rb->frame_size);
504
505 if (status != __packet_get_status(po, h.raw))
506 return NULL;
507
508 return h.raw;
509}
510
511static void *packet_current_frame(struct packet_sock *po,
512 struct packet_ring_buffer *rb,
513 int status)
514{
515 return packet_lookup_frame(po, rb, rb->head, status);
516}
517
518static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
519{
520 del_timer_sync(&pkc->retire_blk_timer);
521}
522
523static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
524 struct sk_buff_head *rb_queue)
525{
526 struct tpacket_kbdq_core *pkc;
527
528 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
529
530 spin_lock_bh(&rb_queue->lock);
531 pkc->delete_blk_timer = 1;
532 spin_unlock_bh(&rb_queue->lock);
533
534 prb_del_retire_blk_timer(pkc);
535}
536
537static void prb_init_blk_timer(struct packet_sock *po,
538 struct tpacket_kbdq_core *pkc,
539 void (*func) (unsigned long))
540{
541 init_timer(&pkc->retire_blk_timer);
542 pkc->retire_blk_timer.data = (long)po;
543 pkc->retire_blk_timer.function = func;
544 pkc->retire_blk_timer.expires = jiffies;
545}
546
547static void prb_setup_retire_blk_timer(struct packet_sock *po)
548{
549 struct tpacket_kbdq_core *pkc;
550
551 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
552 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
553}
554
555static int prb_calc_retire_blk_tmo(struct packet_sock *po,
556 int blk_size_in_bytes)
557{
558 struct net_device *dev;
559 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
560 struct ethtool_link_ksettings ecmd;
561 int err;
562
563 rtnl_lock();
564 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
565 if (unlikely(!dev)) {
566 rtnl_unlock();
567 return DEFAULT_PRB_RETIRE_TOV;
568 }
569 err = __ethtool_get_link_ksettings(dev, &ecmd);
570 rtnl_unlock();
571 if (!err) {
572 /*
573 * If the link speed is so slow you don't really
574 * need to worry about perf anyways
575 */
576 if (ecmd.base.speed < SPEED_1000 ||
577 ecmd.base.speed == SPEED_UNKNOWN) {
578 return DEFAULT_PRB_RETIRE_TOV;
579 } else {
580 msec = 1;
581 div = ecmd.base.speed / 1000;
582 }
583 }
584
585 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
586
587 if (div)
588 mbits /= div;
589
590 tmo = mbits * msec;
591
592 if (div)
593 return tmo+1;
594 return tmo;
595}
596
597static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
598 union tpacket_req_u *req_u)
599{
600 p1->feature_req_word = req_u->req3.tp_feature_req_word;
601}
602
603static void init_prb_bdqc(struct packet_sock *po,
604 struct packet_ring_buffer *rb,
605 struct pgv *pg_vec,
606 union tpacket_req_u *req_u)
607{
608 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
609 struct tpacket_block_desc *pbd;
610
611 memset(p1, 0x0, sizeof(*p1));
612
613 p1->knxt_seq_num = 1;
614 p1->pkbdq = pg_vec;
615 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
616 p1->pkblk_start = pg_vec[0].buffer;
617 p1->kblk_size = req_u->req3.tp_block_size;
618 p1->knum_blocks = req_u->req3.tp_block_nr;
619 p1->hdrlen = po->tp_hdrlen;
620 p1->version = po->tp_version;
621 p1->last_kactive_blk_num = 0;
622 po->stats.stats3.tp_freeze_q_cnt = 0;
623 if (req_u->req3.tp_retire_blk_tov)
624 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
625 else
626 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
627 req_u->req3.tp_block_size);
628 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
629 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
630
631 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
632 prb_init_ft_ops(p1, req_u);
633 prb_setup_retire_blk_timer(po);
634 prb_open_block(p1, pbd);
635}
636
637/* Do NOT update the last_blk_num first.
638 * Assumes sk_buff_head lock is held.
639 */
640static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
641{
642 mod_timer(&pkc->retire_blk_timer,
643 jiffies + pkc->tov_in_jiffies);
644 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
645}
646
647/*
648 * Timer logic:
649 * 1) We refresh the timer only when we open a block.
650 * By doing this we don't waste cycles refreshing the timer
651 * on packet-by-packet basis.
652 *
653 * With a 1MB block-size, on a 1Gbps line, it will take
654 * i) ~8 ms to fill a block + ii) memcpy etc.
655 * In this cut we are not accounting for the memcpy time.
656 *
657 * So, if the user sets the 'tmo' to 10ms then the timer
658 * will never fire while the block is still getting filled
659 * (which is what we want). However, the user could choose
660 * to close a block early and that's fine.
661 *
662 * But when the timer does fire, we check whether or not to refresh it.
663 * Since the tmo granularity is in msecs, it is not too expensive
664 * to refresh the timer, lets say every '8' msecs.
665 * Either the user can set the 'tmo' or we can derive it based on
666 * a) line-speed and b) block-size.
667 * prb_calc_retire_blk_tmo() calculates the tmo.
668 *
669 */
670static void prb_retire_rx_blk_timer_expired(unsigned long data)
671{
672 struct packet_sock *po = (struct packet_sock *)data;
673 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
674 unsigned int frozen;
675 struct tpacket_block_desc *pbd;
676
677 spin_lock(&po->sk.sk_receive_queue.lock);
678
679 frozen = prb_queue_frozen(pkc);
680 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
681
682 if (unlikely(pkc->delete_blk_timer))
683 goto out;
684
685 /* We only need to plug the race when the block is partially filled.
686 * tpacket_rcv:
687 * lock(); increment BLOCK_NUM_PKTS; unlock()
688 * copy_bits() is in progress ...
689 * timer fires on other cpu:
690 * we can't retire the current block because copy_bits
691 * is in progress.
692 *
693 */
694 if (BLOCK_NUM_PKTS(pbd)) {
695 while (atomic_read(&pkc->blk_fill_in_prog)) {
696 /* Waiting for skb_copy_bits to finish... */
697 cpu_relax();
698 }
699 }
700
701 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
702 if (!frozen) {
703 if (!BLOCK_NUM_PKTS(pbd)) {
704 /* An empty block. Just refresh the timer. */
705 goto refresh_timer;
706 }
707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
708 if (!prb_dispatch_next_block(pkc, po))
709 goto refresh_timer;
710 else
711 goto out;
712 } else {
713 /* Case 1. Queue was frozen because user-space was
714 * lagging behind.
715 */
716 if (prb_curr_blk_in_use(pkc, pbd)) {
717 /*
718 * Ok, user-space is still behind.
719 * So just refresh the timer.
720 */
721 goto refresh_timer;
722 } else {
723 /* Case 2. queue was frozen,user-space caught up,
724 * now the link went idle && the timer fired.
725 * We don't have a block to close.So we open this
726 * block and restart the timer.
727 * opening a block thaws the queue,restarts timer
728 * Thawing/timer-refresh is a side effect.
729 */
730 prb_open_block(pkc, pbd);
731 goto out;
732 }
733 }
734 }
735
736refresh_timer:
737 _prb_refresh_rx_retire_blk_timer(pkc);
738
739out:
740 spin_unlock(&po->sk.sk_receive_queue.lock);
741}
742
743static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
744 struct tpacket_block_desc *pbd1, __u32 status)
745{
746 /* Flush everything minus the block header */
747
748#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
749 u8 *start, *end;
750
751 start = (u8 *)pbd1;
752
753 /* Skip the block header(we know header WILL fit in 4K) */
754 start += PAGE_SIZE;
755
756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
757 for (; start < end; start += PAGE_SIZE)
758 flush_dcache_page(pgv_to_page(start));
759
760 smp_wmb();
761#endif
762
763 /* Now update the block status. */
764
765 BLOCK_STATUS(pbd1) = status;
766
767 /* Flush the block header */
768
769#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
770 start = (u8 *)pbd1;
771 flush_dcache_page(pgv_to_page(start));
772
773 smp_wmb();
774#endif
775}
776
777/*
778 * Side effect:
779 *
780 * 1) flush the block
781 * 2) Increment active_blk_num
782 *
783 * Note:We DONT refresh the timer on purpose.
784 * Because almost always the next block will be opened.
785 */
786static void prb_close_block(struct tpacket_kbdq_core *pkc1,
787 struct tpacket_block_desc *pbd1,
788 struct packet_sock *po, unsigned int stat)
789{
790 __u32 status = TP_STATUS_USER | stat;
791
792 struct tpacket3_hdr *last_pkt;
793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
794 struct sock *sk = &po->sk;
795
796 if (po->stats.stats3.tp_drops)
797 status |= TP_STATUS_LOSING;
798
799 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
800 last_pkt->tp_next_offset = 0;
801
802 /* Get the ts of the last pkt */
803 if (BLOCK_NUM_PKTS(pbd1)) {
804 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
805 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
806 } else {
807 /* Ok, we tmo'd - so get the current time.
808 *
809 * It shouldn't really happen as we don't close empty
810 * blocks. See prb_retire_rx_blk_timer_expired().
811 */
812 struct timespec ts;
813 getnstimeofday(&ts);
814 h1->ts_last_pkt.ts_sec = ts.tv_sec;
815 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
816 }
817
818 smp_wmb();
819
820 /* Flush the block */
821 prb_flush_block(pkc1, pbd1, status);
822
823 sk->sk_data_ready(sk);
824
825 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
826}
827
828static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
829{
830 pkc->reset_pending_on_curr_blk = 0;
831}
832
833/*
834 * Side effect of opening a block:
835 *
836 * 1) prb_queue is thawed.
837 * 2) retire_blk_timer is refreshed.
838 *
839 */
840static void prb_open_block(struct tpacket_kbdq_core *pkc1,
841 struct tpacket_block_desc *pbd1)
842{
843 struct timespec ts;
844 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
845
846 smp_rmb();
847
848 /* We could have just memset this but we will lose the
849 * flexibility of making the priv area sticky
850 */
851
852 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
853 BLOCK_NUM_PKTS(pbd1) = 0;
854 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
855
856 getnstimeofday(&ts);
857
858 h1->ts_first_pkt.ts_sec = ts.tv_sec;
859 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
860
861 pkc1->pkblk_start = (char *)pbd1;
862 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
863
864 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
865 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
866
867 pbd1->version = pkc1->version;
868 pkc1->prev = pkc1->nxt_offset;
869 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
870
871 prb_thaw_queue(pkc1);
872 _prb_refresh_rx_retire_blk_timer(pkc1);
873
874 smp_wmb();
875}
876
877/*
878 * Queue freeze logic:
879 * 1) Assume tp_block_nr = 8 blocks.
880 * 2) At time 't0', user opens Rx ring.
881 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
882 * 4) user-space is either sleeping or processing block '0'.
883 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
884 * it will close block-7,loop around and try to fill block '0'.
885 * call-flow:
886 * __packet_lookup_frame_in_block
887 * prb_retire_current_block()
888 * prb_dispatch_next_block()
889 * |->(BLOCK_STATUS == USER) evaluates to true
890 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
891 * 6) Now there are two cases:
892 * 6.1) Link goes idle right after the queue is frozen.
893 * But remember, the last open_block() refreshed the timer.
894 * When this timer expires,it will refresh itself so that we can
895 * re-open block-0 in near future.
896 * 6.2) Link is busy and keeps on receiving packets. This is a simple
897 * case and __packet_lookup_frame_in_block will check if block-0
898 * is free and can now be re-used.
899 */
900static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
901 struct packet_sock *po)
902{
903 pkc->reset_pending_on_curr_blk = 1;
904 po->stats.stats3.tp_freeze_q_cnt++;
905}
906
907#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
908
909/*
910 * If the next block is free then we will dispatch it
911 * and return a good offset.
912 * Else, we will freeze the queue.
913 * So, caller must check the return value.
914 */
915static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
916 struct packet_sock *po)
917{
918 struct tpacket_block_desc *pbd;
919
920 smp_rmb();
921
922 /* 1. Get current block num */
923 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
924
925 /* 2. If this block is currently in_use then freeze the queue */
926 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
927 prb_freeze_queue(pkc, po);
928 return NULL;
929 }
930
931 /*
932 * 3.
933 * open this block and return the offset where the first packet
934 * needs to get stored.
935 */
936 prb_open_block(pkc, pbd);
937 return (void *)pkc->nxt_offset;
938}
939
940static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
941 struct packet_sock *po, unsigned int status)
942{
943 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
944
945 /* retire/close the current block */
946 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
947 /*
948 * Plug the case where copy_bits() is in progress on
949 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
950 * have space to copy the pkt in the current block and
951 * called prb_retire_current_block()
952 *
953 * We don't need to worry about the TMO case because
954 * the timer-handler already handled this case.
955 */
956 if (!(status & TP_STATUS_BLK_TMO)) {
957 while (atomic_read(&pkc->blk_fill_in_prog)) {
958 /* Waiting for skb_copy_bits to finish... */
959 cpu_relax();
960 }
961 }
962 prb_close_block(pkc, pbd, po, status);
963 return;
964 }
965}
966
967static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
968 struct tpacket_block_desc *pbd)
969{
970 return TP_STATUS_USER & BLOCK_STATUS(pbd);
971}
972
973static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
974{
975 return pkc->reset_pending_on_curr_blk;
976}
977
978static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
979{
980 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
981 atomic_dec(&pkc->blk_fill_in_prog);
982}
983
984static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
985 struct tpacket3_hdr *ppd)
986{
987 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
988}
989
990static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
991 struct tpacket3_hdr *ppd)
992{
993 ppd->hv1.tp_rxhash = 0;
994}
995
996static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
997 struct tpacket3_hdr *ppd)
998{
999 if (skb_vlan_tag_present(pkc->skb)) {
1000 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1001 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1002 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1003 } else {
1004 ppd->hv1.tp_vlan_tci = 0;
1005 ppd->hv1.tp_vlan_tpid = 0;
1006 ppd->tp_status = TP_STATUS_AVAILABLE;
1007 }
1008}
1009
1010static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1011 struct tpacket3_hdr *ppd)
1012{
1013 ppd->hv1.tp_padding = 0;
1014 prb_fill_vlan_info(pkc, ppd);
1015
1016 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1017 prb_fill_rxhash(pkc, ppd);
1018 else
1019 prb_clear_rxhash(pkc, ppd);
1020}
1021
1022static void prb_fill_curr_block(char *curr,
1023 struct tpacket_kbdq_core *pkc,
1024 struct tpacket_block_desc *pbd,
1025 unsigned int len)
1026{
1027 struct tpacket3_hdr *ppd;
1028
1029 ppd = (struct tpacket3_hdr *)curr;
1030 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1031 pkc->prev = curr;
1032 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1033 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1034 BLOCK_NUM_PKTS(pbd) += 1;
1035 atomic_inc(&pkc->blk_fill_in_prog);
1036 prb_run_all_ft_ops(pkc, ppd);
1037}
1038
1039/* Assumes caller has the sk->rx_queue.lock */
1040static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1041 struct sk_buff *skb,
1042 int status,
1043 unsigned int len
1044 )
1045{
1046 struct tpacket_kbdq_core *pkc;
1047 struct tpacket_block_desc *pbd;
1048 char *curr, *end;
1049
1050 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1051 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1052
1053 /* Queue is frozen when user space is lagging behind */
1054 if (prb_queue_frozen(pkc)) {
1055 /*
1056 * Check if that last block which caused the queue to freeze,
1057 * is still in_use by user-space.
1058 */
1059 if (prb_curr_blk_in_use(pkc, pbd)) {
1060 /* Can't record this packet */
1061 return NULL;
1062 } else {
1063 /*
1064 * Ok, the block was released by user-space.
1065 * Now let's open that block.
1066 * opening a block also thaws the queue.
1067 * Thawing is a side effect.
1068 */
1069 prb_open_block(pkc, pbd);
1070 }
1071 }
1072
1073 smp_mb();
1074 curr = pkc->nxt_offset;
1075 pkc->skb = skb;
1076 end = (char *)pbd + pkc->kblk_size;
1077
1078 /* first try the current block */
1079 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1080 prb_fill_curr_block(curr, pkc, pbd, len);
1081 return (void *)curr;
1082 }
1083
1084 /* Ok, close the current block */
1085 prb_retire_current_block(pkc, po, 0);
1086
1087 /* Now, try to dispatch the next block */
1088 curr = (char *)prb_dispatch_next_block(pkc, po);
1089 if (curr) {
1090 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1091 prb_fill_curr_block(curr, pkc, pbd, len);
1092 return (void *)curr;
1093 }
1094
1095 /*
1096 * No free blocks are available.user_space hasn't caught up yet.
1097 * Queue was just frozen and now this packet will get dropped.
1098 */
1099 return NULL;
1100}
1101
1102static void *packet_current_rx_frame(struct packet_sock *po,
1103 struct sk_buff *skb,
1104 int status, unsigned int len)
1105{
1106 char *curr = NULL;
1107 switch (po->tp_version) {
1108 case TPACKET_V1:
1109 case TPACKET_V2:
1110 curr = packet_lookup_frame(po, &po->rx_ring,
1111 po->rx_ring.head, status);
1112 return curr;
1113 case TPACKET_V3:
1114 return __packet_lookup_frame_in_block(po, skb, status, len);
1115 default:
1116 WARN(1, "TPACKET version not supported\n");
1117 BUG();
1118 return NULL;
1119 }
1120}
1121
1122static void *prb_lookup_block(struct packet_sock *po,
1123 struct packet_ring_buffer *rb,
1124 unsigned int idx,
1125 int status)
1126{
1127 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1128 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1129
1130 if (status != BLOCK_STATUS(pbd))
1131 return NULL;
1132 return pbd;
1133}
1134
1135static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1136{
1137 unsigned int prev;
1138 if (rb->prb_bdqc.kactive_blk_num)
1139 prev = rb->prb_bdqc.kactive_blk_num-1;
1140 else
1141 prev = rb->prb_bdqc.knum_blocks-1;
1142 return prev;
1143}
1144
1145/* Assumes caller has held the rx_queue.lock */
1146static void *__prb_previous_block(struct packet_sock *po,
1147 struct packet_ring_buffer *rb,
1148 int status)
1149{
1150 unsigned int previous = prb_previous_blk_num(rb);
1151 return prb_lookup_block(po, rb, previous, status);
1152}
1153
1154static void *packet_previous_rx_frame(struct packet_sock *po,
1155 struct packet_ring_buffer *rb,
1156 int status)
1157{
1158 if (po->tp_version <= TPACKET_V2)
1159 return packet_previous_frame(po, rb, status);
1160
1161 return __prb_previous_block(po, rb, status);
1162}
1163
1164static void packet_increment_rx_head(struct packet_sock *po,
1165 struct packet_ring_buffer *rb)
1166{
1167 switch (po->tp_version) {
1168 case TPACKET_V1:
1169 case TPACKET_V2:
1170 return packet_increment_head(rb);
1171 case TPACKET_V3:
1172 default:
1173 WARN(1, "TPACKET version not supported.\n");
1174 BUG();
1175 return;
1176 }
1177}
1178
1179static void *packet_previous_frame(struct packet_sock *po,
1180 struct packet_ring_buffer *rb,
1181 int status)
1182{
1183 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1184 return packet_lookup_frame(po, rb, previous, status);
1185}
1186
1187static void packet_increment_head(struct packet_ring_buffer *buff)
1188{
1189 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1190}
1191
1192static void packet_inc_pending(struct packet_ring_buffer *rb)
1193{
1194 this_cpu_inc(*rb->pending_refcnt);
1195}
1196
1197static void packet_dec_pending(struct packet_ring_buffer *rb)
1198{
1199 this_cpu_dec(*rb->pending_refcnt);
1200}
1201
1202static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1203{
1204 unsigned int refcnt = 0;
1205 int cpu;
1206
1207 /* We don't use pending refcount in rx_ring. */
1208 if (rb->pending_refcnt == NULL)
1209 return 0;
1210
1211 for_each_possible_cpu(cpu)
1212 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1213
1214 return refcnt;
1215}
1216
1217static int packet_alloc_pending(struct packet_sock *po)
1218{
1219 po->rx_ring.pending_refcnt = NULL;
1220
1221 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1222 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1223 return -ENOBUFS;
1224
1225 return 0;
1226}
1227
1228static void packet_free_pending(struct packet_sock *po)
1229{
1230 free_percpu(po->tx_ring.pending_refcnt);
1231}
1232
1233#define ROOM_POW_OFF 2
1234#define ROOM_NONE 0x0
1235#define ROOM_LOW 0x1
1236#define ROOM_NORMAL 0x2
1237
1238static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1239{
1240 int idx, len;
1241
1242 len = po->rx_ring.frame_max + 1;
1243 idx = po->rx_ring.head;
1244 if (pow_off)
1245 idx += len >> pow_off;
1246 if (idx >= len)
1247 idx -= len;
1248 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1249}
1250
1251static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1252{
1253 int idx, len;
1254
1255 len = po->rx_ring.prb_bdqc.knum_blocks;
1256 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1257 if (pow_off)
1258 idx += len >> pow_off;
1259 if (idx >= len)
1260 idx -= len;
1261 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1262}
1263
1264static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1265{
1266 struct sock *sk = &po->sk;
1267 int ret = ROOM_NONE;
1268
1269 if (po->prot_hook.func != tpacket_rcv) {
1270 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1271 - (skb ? skb->truesize : 0);
1272 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1273 return ROOM_NORMAL;
1274 else if (avail > 0)
1275 return ROOM_LOW;
1276 else
1277 return ROOM_NONE;
1278 }
1279
1280 if (po->tp_version == TPACKET_V3) {
1281 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1282 ret = ROOM_NORMAL;
1283 else if (__tpacket_v3_has_room(po, 0))
1284 ret = ROOM_LOW;
1285 } else {
1286 if (__tpacket_has_room(po, ROOM_POW_OFF))
1287 ret = ROOM_NORMAL;
1288 else if (__tpacket_has_room(po, 0))
1289 ret = ROOM_LOW;
1290 }
1291
1292 return ret;
1293}
1294
1295static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1296{
1297 int ret;
1298 bool has_room;
1299
1300 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1301 ret = __packet_rcv_has_room(po, skb);
1302 has_room = ret == ROOM_NORMAL;
1303 if (po->pressure == has_room)
1304 po->pressure = !has_room;
1305 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1306
1307 return ret;
1308}
1309
1310static void packet_sock_destruct(struct sock *sk)
1311{
1312 skb_queue_purge(&sk->sk_error_queue);
1313
1314 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1315 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1316
1317 if (!sock_flag(sk, SOCK_DEAD)) {
1318 pr_err("Attempt to release alive packet socket: %p\n", sk);
1319 return;
1320 }
1321
1322 sk_refcnt_debug_dec(sk);
1323}
1324
1325static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1326{
1327 u32 rxhash;
1328 int i, count = 0;
1329
1330 rxhash = skb_get_hash(skb);
1331 for (i = 0; i < ROLLOVER_HLEN; i++)
1332 if (po->rollover->history[i] == rxhash)
1333 count++;
1334
1335 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1336 return count > (ROLLOVER_HLEN >> 1);
1337}
1338
1339static unsigned int fanout_demux_hash(struct packet_fanout *f,
1340 struct sk_buff *skb,
1341 unsigned int num)
1342{
1343 return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1344}
1345
1346static unsigned int fanout_demux_lb(struct packet_fanout *f,
1347 struct sk_buff *skb,
1348 unsigned int num)
1349{
1350 unsigned int val = atomic_inc_return(&f->rr_cur);
1351
1352 return val % num;
1353}
1354
1355static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1356 struct sk_buff *skb,
1357 unsigned int num)
1358{
1359 return smp_processor_id() % num;
1360}
1361
1362static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1363 struct sk_buff *skb,
1364 unsigned int num)
1365{
1366 return prandom_u32_max(num);
1367}
1368
1369static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1370 struct sk_buff *skb,
1371 unsigned int idx, bool try_self,
1372 unsigned int num)
1373{
1374 struct packet_sock *po, *po_next, *po_skip = NULL;
1375 unsigned int i, j, room = ROOM_NONE;
1376
1377 po = pkt_sk(f->arr[idx]);
1378
1379 if (try_self) {
1380 room = packet_rcv_has_room(po, skb);
1381 if (room == ROOM_NORMAL ||
1382 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1383 return idx;
1384 po_skip = po;
1385 }
1386
1387 i = j = min_t(int, po->rollover->sock, num - 1);
1388 do {
1389 po_next = pkt_sk(f->arr[i]);
1390 if (po_next != po_skip && !po_next->pressure &&
1391 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1392 if (i != j)
1393 po->rollover->sock = i;
1394 atomic_long_inc(&po->rollover->num);
1395 if (room == ROOM_LOW)
1396 atomic_long_inc(&po->rollover->num_huge);
1397 return i;
1398 }
1399
1400 if (++i == num)
1401 i = 0;
1402 } while (i != j);
1403
1404 atomic_long_inc(&po->rollover->num_failed);
1405 return idx;
1406}
1407
1408static unsigned int fanout_demux_qm(struct packet_fanout *f,
1409 struct sk_buff *skb,
1410 unsigned int num)
1411{
1412 return skb_get_queue_mapping(skb) % num;
1413}
1414
1415static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1416 struct sk_buff *skb,
1417 unsigned int num)
1418{
1419 struct bpf_prog *prog;
1420 unsigned int ret = 0;
1421
1422 rcu_read_lock();
1423 prog = rcu_dereference(f->bpf_prog);
1424 if (prog)
1425 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1426 rcu_read_unlock();
1427
1428 return ret;
1429}
1430
1431static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1432{
1433 return f->flags & (flag >> 8);
1434}
1435
1436static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1437 struct packet_type *pt, struct net_device *orig_dev)
1438{
1439 struct packet_fanout *f = pt->af_packet_priv;
1440 unsigned int num = READ_ONCE(f->num_members);
1441 struct net *net = read_pnet(&f->net);
1442 struct packet_sock *po;
1443 unsigned int idx;
1444
1445 if (!net_eq(dev_net(dev), net) || !num) {
1446 kfree_skb(skb);
1447 return 0;
1448 }
1449
1450 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1451 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1452 if (!skb)
1453 return 0;
1454 }
1455 switch (f->type) {
1456 case PACKET_FANOUT_HASH:
1457 default:
1458 idx = fanout_demux_hash(f, skb, num);
1459 break;
1460 case PACKET_FANOUT_LB:
1461 idx = fanout_demux_lb(f, skb, num);
1462 break;
1463 case PACKET_FANOUT_CPU:
1464 idx = fanout_demux_cpu(f, skb, num);
1465 break;
1466 case PACKET_FANOUT_RND:
1467 idx = fanout_demux_rnd(f, skb, num);
1468 break;
1469 case PACKET_FANOUT_QM:
1470 idx = fanout_demux_qm(f, skb, num);
1471 break;
1472 case PACKET_FANOUT_ROLLOVER:
1473 idx = fanout_demux_rollover(f, skb, 0, false, num);
1474 break;
1475 case PACKET_FANOUT_CBPF:
1476 case PACKET_FANOUT_EBPF:
1477 idx = fanout_demux_bpf(f, skb, num);
1478 break;
1479 }
1480
1481 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1482 idx = fanout_demux_rollover(f, skb, idx, true, num);
1483
1484 po = pkt_sk(f->arr[idx]);
1485 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1486}
1487
1488DEFINE_MUTEX(fanout_mutex);
1489EXPORT_SYMBOL_GPL(fanout_mutex);
1490static LIST_HEAD(fanout_list);
1491
1492static void __fanout_link(struct sock *sk, struct packet_sock *po)
1493{
1494 struct packet_fanout *f = po->fanout;
1495
1496 spin_lock(&f->lock);
1497 f->arr[f->num_members] = sk;
1498 smp_wmb();
1499 f->num_members++;
1500 if (f->num_members == 1)
1501 dev_add_pack(&f->prot_hook);
1502 spin_unlock(&f->lock);
1503}
1504
1505static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1506{
1507 struct packet_fanout *f = po->fanout;
1508 int i;
1509
1510 spin_lock(&f->lock);
1511 for (i = 0; i < f->num_members; i++) {
1512 if (f->arr[i] == sk)
1513 break;
1514 }
1515 BUG_ON(i >= f->num_members);
1516 f->arr[i] = f->arr[f->num_members - 1];
1517 f->num_members--;
1518 if (f->num_members == 0)
1519 __dev_remove_pack(&f->prot_hook);
1520 spin_unlock(&f->lock);
1521}
1522
1523static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1524{
1525 if (sk->sk_family != PF_PACKET)
1526 return false;
1527
1528 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1529}
1530
1531static void fanout_init_data(struct packet_fanout *f)
1532{
1533 switch (f->type) {
1534 case PACKET_FANOUT_LB:
1535 atomic_set(&f->rr_cur, 0);
1536 break;
1537 case PACKET_FANOUT_CBPF:
1538 case PACKET_FANOUT_EBPF:
1539 RCU_INIT_POINTER(f->bpf_prog, NULL);
1540 break;
1541 }
1542}
1543
1544static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1545{
1546 struct bpf_prog *old;
1547
1548 spin_lock(&f->lock);
1549 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1550 rcu_assign_pointer(f->bpf_prog, new);
1551 spin_unlock(&f->lock);
1552
1553 if (old) {
1554 synchronize_net();
1555 bpf_prog_destroy(old);
1556 }
1557}
1558
1559static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1560 unsigned int len)
1561{
1562 struct bpf_prog *new;
1563 struct sock_fprog fprog;
1564 int ret;
1565
1566 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1567 return -EPERM;
1568 if (len != sizeof(fprog))
1569 return -EINVAL;
1570 if (copy_from_user(&fprog, data, len))
1571 return -EFAULT;
1572
1573 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1574 if (ret)
1575 return ret;
1576
1577 __fanout_set_data_bpf(po->fanout, new);
1578 return 0;
1579}
1580
1581static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1582 unsigned int len)
1583{
1584 struct bpf_prog *new;
1585 u32 fd;
1586
1587 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1588 return -EPERM;
1589 if (len != sizeof(fd))
1590 return -EINVAL;
1591 if (copy_from_user(&fd, data, len))
1592 return -EFAULT;
1593
1594 new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1595 if (IS_ERR(new))
1596 return PTR_ERR(new);
1597
1598 __fanout_set_data_bpf(po->fanout, new);
1599 return 0;
1600}
1601
1602static int fanout_set_data(struct packet_sock *po, char __user *data,
1603 unsigned int len)
1604{
1605 switch (po->fanout->type) {
1606 case PACKET_FANOUT_CBPF:
1607 return fanout_set_data_cbpf(po, data, len);
1608 case PACKET_FANOUT_EBPF:
1609 return fanout_set_data_ebpf(po, data, len);
1610 default:
1611 return -EINVAL;
1612 };
1613}
1614
1615static void fanout_release_data(struct packet_fanout *f)
1616{
1617 switch (f->type) {
1618 case PACKET_FANOUT_CBPF:
1619 case PACKET_FANOUT_EBPF:
1620 __fanout_set_data_bpf(f, NULL);
1621 };
1622}
1623
1624static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1625{
1626 struct packet_rollover *rollover = NULL;
1627 struct packet_sock *po = pkt_sk(sk);
1628 struct packet_fanout *f, *match;
1629 u8 type = type_flags & 0xff;
1630 u8 flags = type_flags >> 8;
1631 int err;
1632
1633 switch (type) {
1634 case PACKET_FANOUT_ROLLOVER:
1635 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1636 return -EINVAL;
1637 case PACKET_FANOUT_HASH:
1638 case PACKET_FANOUT_LB:
1639 case PACKET_FANOUT_CPU:
1640 case PACKET_FANOUT_RND:
1641 case PACKET_FANOUT_QM:
1642 case PACKET_FANOUT_CBPF:
1643 case PACKET_FANOUT_EBPF:
1644 break;
1645 default:
1646 return -EINVAL;
1647 }
1648
1649 mutex_lock(&fanout_mutex);
1650
1651 err = -EINVAL;
1652 if (!po->running)
1653 goto out;
1654
1655 err = -EALREADY;
1656 if (po->fanout)
1657 goto out;
1658
1659 if (type == PACKET_FANOUT_ROLLOVER ||
1660 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1661 err = -ENOMEM;
1662 rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
1663 if (!rollover)
1664 goto out;
1665 atomic_long_set(&rollover->num, 0);
1666 atomic_long_set(&rollover->num_huge, 0);
1667 atomic_long_set(&rollover->num_failed, 0);
1668 po->rollover = rollover;
1669 }
1670
1671 match = NULL;
1672 list_for_each_entry(f, &fanout_list, list) {
1673 if (f->id == id &&
1674 read_pnet(&f->net) == sock_net(sk)) {
1675 match = f;
1676 break;
1677 }
1678 }
1679 err = -EINVAL;
1680 if (match && match->flags != flags)
1681 goto out;
1682 if (!match) {
1683 err = -ENOMEM;
1684 match = kzalloc(sizeof(*match), GFP_KERNEL);
1685 if (!match)
1686 goto out;
1687 write_pnet(&match->net, sock_net(sk));
1688 match->id = id;
1689 match->type = type;
1690 match->flags = flags;
1691 INIT_LIST_HEAD(&match->list);
1692 spin_lock_init(&match->lock);
1693 atomic_set(&match->sk_ref, 0);
1694 fanout_init_data(match);
1695 match->prot_hook.type = po->prot_hook.type;
1696 match->prot_hook.dev = po->prot_hook.dev;
1697 match->prot_hook.func = packet_rcv_fanout;
1698 match->prot_hook.af_packet_priv = match;
1699 match->prot_hook.id_match = match_fanout_group;
1700 list_add(&match->list, &fanout_list);
1701 }
1702 err = -EINVAL;
1703 if (match->type == type &&
1704 match->prot_hook.type == po->prot_hook.type &&
1705 match->prot_hook.dev == po->prot_hook.dev) {
1706 err = -ENOSPC;
1707 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1708 __dev_remove_pack(&po->prot_hook);
1709 po->fanout = match;
1710 atomic_inc(&match->sk_ref);
1711 __fanout_link(sk, po);
1712 err = 0;
1713 }
1714 }
1715out:
1716 if (err && rollover) {
1717 kfree(rollover);
1718 po->rollover = NULL;
1719 }
1720 mutex_unlock(&fanout_mutex);
1721 return err;
1722}
1723
1724/* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
1725 * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
1726 * It is the responsibility of the caller to call fanout_release_data() and
1727 * free the returned packet_fanout (after synchronize_net())
1728 */
1729static struct packet_fanout *fanout_release(struct sock *sk)
1730{
1731 struct packet_sock *po = pkt_sk(sk);
1732 struct packet_fanout *f;
1733
1734 mutex_lock(&fanout_mutex);
1735 f = po->fanout;
1736 if (f) {
1737 po->fanout = NULL;
1738
1739 if (atomic_dec_and_test(&f->sk_ref))
1740 list_del(&f->list);
1741 else
1742 f = NULL;
1743
1744 if (po->rollover)
1745 kfree_rcu(po->rollover, rcu);
1746 }
1747 mutex_unlock(&fanout_mutex);
1748
1749 return f;
1750}
1751
1752static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1753 struct sk_buff *skb)
1754{
1755 /* Earlier code assumed this would be a VLAN pkt, double-check
1756 * this now that we have the actual packet in hand. We can only
1757 * do this check on Ethernet devices.
1758 */
1759 if (unlikely(dev->type != ARPHRD_ETHER))
1760 return false;
1761
1762 skb_reset_mac_header(skb);
1763 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1764}
1765
1766static const struct proto_ops packet_ops;
1767
1768static const struct proto_ops packet_ops_spkt;
1769
1770static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1771 struct packet_type *pt, struct net_device *orig_dev)
1772{
1773 struct sock *sk;
1774 struct sockaddr_pkt *spkt;
1775
1776 /*
1777 * When we registered the protocol we saved the socket in the data
1778 * field for just this event.
1779 */
1780
1781 sk = pt->af_packet_priv;
1782
1783 /*
1784 * Yank back the headers [hope the device set this
1785 * right or kerboom...]
1786 *
1787 * Incoming packets have ll header pulled,
1788 * push it back.
1789 *
1790 * For outgoing ones skb->data == skb_mac_header(skb)
1791 * so that this procedure is noop.
1792 */
1793
1794 if (skb->pkt_type == PACKET_LOOPBACK)
1795 goto out;
1796
1797 if (!net_eq(dev_net(dev), sock_net(sk)))
1798 goto out;
1799
1800 skb = skb_share_check(skb, GFP_ATOMIC);
1801 if (skb == NULL)
1802 goto oom;
1803
1804 /* drop any routing info */
1805 skb_dst_drop(skb);
1806
1807 /* drop conntrack reference */
1808 nf_reset(skb);
1809
1810 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1811
1812 skb_push(skb, skb->data - skb_mac_header(skb));
1813
1814 /*
1815 * The SOCK_PACKET socket receives _all_ frames.
1816 */
1817
1818 spkt->spkt_family = dev->type;
1819 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1820 spkt->spkt_protocol = skb->protocol;
1821
1822 /*
1823 * Charge the memory to the socket. This is done specifically
1824 * to prevent sockets using all the memory up.
1825 */
1826
1827 if (sock_queue_rcv_skb(sk, skb) == 0)
1828 return 0;
1829
1830out:
1831 kfree_skb(skb);
1832oom:
1833 return 0;
1834}
1835
1836
1837/*
1838 * Output a raw packet to a device layer. This bypasses all the other
1839 * protocol layers and you must therefore supply it with a complete frame
1840 */
1841
1842static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1843 size_t len)
1844{
1845 struct sock *sk = sock->sk;
1846 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1847 struct sk_buff *skb = NULL;
1848 struct net_device *dev;
1849 struct sockcm_cookie sockc;
1850 __be16 proto = 0;
1851 int err;
1852 int extra_len = 0;
1853
1854 /*
1855 * Get and verify the address.
1856 */
1857
1858 if (saddr) {
1859 if (msg->msg_namelen < sizeof(struct sockaddr))
1860 return -EINVAL;
1861 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1862 proto = saddr->spkt_protocol;
1863 } else
1864 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1865
1866 /*
1867 * Find the device first to size check it
1868 */
1869
1870 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1871retry:
1872 rcu_read_lock();
1873 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1874 err = -ENODEV;
1875 if (dev == NULL)
1876 goto out_unlock;
1877
1878 err = -ENETDOWN;
1879 if (!(dev->flags & IFF_UP))
1880 goto out_unlock;
1881
1882 /*
1883 * You may not queue a frame bigger than the mtu. This is the lowest level
1884 * raw protocol and you must do your own fragmentation at this level.
1885 */
1886
1887 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1888 if (!netif_supports_nofcs(dev)) {
1889 err = -EPROTONOSUPPORT;
1890 goto out_unlock;
1891 }
1892 extra_len = 4; /* We're doing our own CRC */
1893 }
1894
1895 err = -EMSGSIZE;
1896 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1897 goto out_unlock;
1898
1899 if (!skb) {
1900 size_t reserved = LL_RESERVED_SPACE(dev);
1901 int tlen = dev->needed_tailroom;
1902 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1903
1904 rcu_read_unlock();
1905 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1906 if (skb == NULL)
1907 return -ENOBUFS;
1908 /* FIXME: Save some space for broken drivers that write a hard
1909 * header at transmission time by themselves. PPP is the notable
1910 * one here. This should really be fixed at the driver level.
1911 */
1912 skb_reserve(skb, reserved);
1913 skb_reset_network_header(skb);
1914
1915 /* Try to align data part correctly */
1916 if (hhlen) {
1917 skb->data -= hhlen;
1918 skb->tail -= hhlen;
1919 if (len < hhlen)
1920 skb_reset_network_header(skb);
1921 }
1922 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1923 if (err)
1924 goto out_free;
1925 goto retry;
1926 }
1927
1928 if (!dev_validate_header(dev, skb->data, len)) {
1929 err = -EINVAL;
1930 goto out_unlock;
1931 }
1932 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1933 !packet_extra_vlan_len_allowed(dev, skb)) {
1934 err = -EMSGSIZE;
1935 goto out_unlock;
1936 }
1937
1938 sockc.tsflags = sk->sk_tsflags;
1939 if (msg->msg_controllen) {
1940 err = sock_cmsg_send(sk, msg, &sockc);
1941 if (unlikely(err))
1942 goto out_unlock;
1943 }
1944
1945 skb->protocol = proto;
1946 skb->dev = dev;
1947 skb->priority = sk->sk_priority;
1948 skb->mark = sk->sk_mark;
1949
1950 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
1951
1952 if (unlikely(extra_len == 4))
1953 skb->no_fcs = 1;
1954
1955 skb_probe_transport_header(skb, 0);
1956
1957 dev_queue_xmit(skb);
1958 rcu_read_unlock();
1959 return len;
1960
1961out_unlock:
1962 rcu_read_unlock();
1963out_free:
1964 kfree_skb(skb);
1965 return err;
1966}
1967
1968static unsigned int run_filter(struct sk_buff *skb,
1969 const struct sock *sk,
1970 unsigned int res)
1971{
1972 struct sk_filter *filter;
1973
1974 rcu_read_lock();
1975 filter = rcu_dereference(sk->sk_filter);
1976 if (filter != NULL)
1977 res = bpf_prog_run_clear_cb(filter->prog, skb);
1978 rcu_read_unlock();
1979
1980 return res;
1981}
1982
1983static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
1984 size_t *len)
1985{
1986 struct virtio_net_hdr vnet_hdr;
1987
1988 if (*len < sizeof(vnet_hdr))
1989 return -EINVAL;
1990 *len -= sizeof(vnet_hdr);
1991
1992 if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le(), true))
1993 return -EINVAL;
1994
1995 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
1996}
1997
1998/*
1999 * This function makes lazy skb cloning in hope that most of packets
2000 * are discarded by BPF.
2001 *
2002 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2003 * and skb->cb are mangled. It works because (and until) packets
2004 * falling here are owned by current CPU. Output packets are cloned
2005 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2006 * sequencially, so that if we return skb to original state on exit,
2007 * we will not harm anyone.
2008 */
2009
2010static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2011 struct packet_type *pt, struct net_device *orig_dev)
2012{
2013 struct sock *sk;
2014 struct sockaddr_ll *sll;
2015 struct packet_sock *po;
2016 u8 *skb_head = skb->data;
2017 int skb_len = skb->len;
2018 unsigned int snaplen, res;
2019 bool is_drop_n_account = false;
2020
2021 if (skb->pkt_type == PACKET_LOOPBACK)
2022 goto drop;
2023
2024 sk = pt->af_packet_priv;
2025 po = pkt_sk(sk);
2026
2027 if (!net_eq(dev_net(dev), sock_net(sk)))
2028 goto drop;
2029
2030 skb->dev = dev;
2031
2032 if (dev->header_ops) {
2033 /* The device has an explicit notion of ll header,
2034 * exported to higher levels.
2035 *
2036 * Otherwise, the device hides details of its frame
2037 * structure, so that corresponding packet head is
2038 * never delivered to user.
2039 */
2040 if (sk->sk_type != SOCK_DGRAM)
2041 skb_push(skb, skb->data - skb_mac_header(skb));
2042 else if (skb->pkt_type == PACKET_OUTGOING) {
2043 /* Special case: outgoing packets have ll header at head */
2044 skb_pull(skb, skb_network_offset(skb));
2045 }
2046 }
2047
2048 snaplen = skb->len;
2049
2050 res = run_filter(skb, sk, snaplen);
2051 if (!res)
2052 goto drop_n_restore;
2053 if (snaplen > res)
2054 snaplen = res;
2055
2056 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2057 goto drop_n_acct;
2058
2059 if (skb_shared(skb)) {
2060 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2061 if (nskb == NULL)
2062 goto drop_n_acct;
2063
2064 if (skb_head != skb->data) {
2065 skb->data = skb_head;
2066 skb->len = skb_len;
2067 }
2068 consume_skb(skb);
2069 skb = nskb;
2070 }
2071
2072 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2073
2074 sll = &PACKET_SKB_CB(skb)->sa.ll;
2075 sll->sll_hatype = dev->type;
2076 sll->sll_pkttype = skb->pkt_type;
2077 if (unlikely(po->origdev))
2078 sll->sll_ifindex = orig_dev->ifindex;
2079 else
2080 sll->sll_ifindex = dev->ifindex;
2081
2082 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2083
2084 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2085 * Use their space for storing the original skb length.
2086 */
2087 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2088
2089 if (pskb_trim(skb, snaplen))
2090 goto drop_n_acct;
2091
2092 skb_set_owner_r(skb, sk);
2093 skb->dev = NULL;
2094 skb_dst_drop(skb);
2095
2096 /* drop conntrack reference */
2097 nf_reset(skb);
2098
2099 spin_lock(&sk->sk_receive_queue.lock);
2100 po->stats.stats1.tp_packets++;
2101 sock_skb_set_dropcount(sk, skb);
2102 __skb_queue_tail(&sk->sk_receive_queue, skb);
2103 spin_unlock(&sk->sk_receive_queue.lock);
2104 sk->sk_data_ready(sk);
2105 return 0;
2106
2107drop_n_acct:
2108 is_drop_n_account = true;
2109 spin_lock(&sk->sk_receive_queue.lock);
2110 po->stats.stats1.tp_drops++;
2111 atomic_inc(&sk->sk_drops);
2112 spin_unlock(&sk->sk_receive_queue.lock);
2113
2114drop_n_restore:
2115 if (skb_head != skb->data && skb_shared(skb)) {
2116 skb->data = skb_head;
2117 skb->len = skb_len;
2118 }
2119drop:
2120 if (!is_drop_n_account)
2121 consume_skb(skb);
2122 else
2123 kfree_skb(skb);
2124 return 0;
2125}
2126
2127static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2128 struct packet_type *pt, struct net_device *orig_dev)
2129{
2130 struct sock *sk;
2131 struct packet_sock *po;
2132 struct sockaddr_ll *sll;
2133 union tpacket_uhdr h;
2134 u8 *skb_head = skb->data;
2135 int skb_len = skb->len;
2136 unsigned int snaplen, res;
2137 unsigned long status = TP_STATUS_USER;
2138 unsigned short macoff, netoff, hdrlen;
2139 struct sk_buff *copy_skb = NULL;
2140 struct timespec ts;
2141 __u32 ts_status;
2142 bool is_drop_n_account = false;
2143
2144 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2145 * We may add members to them until current aligned size without forcing
2146 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2147 */
2148 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2149 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2150
2151 if (skb->pkt_type == PACKET_LOOPBACK)
2152 goto drop;
2153
2154 sk = pt->af_packet_priv;
2155 po = pkt_sk(sk);
2156
2157 if (!net_eq(dev_net(dev), sock_net(sk)))
2158 goto drop;
2159
2160 if (dev->header_ops) {
2161 if (sk->sk_type != SOCK_DGRAM)
2162 skb_push(skb, skb->data - skb_mac_header(skb));
2163 else if (skb->pkt_type == PACKET_OUTGOING) {
2164 /* Special case: outgoing packets have ll header at head */
2165 skb_pull(skb, skb_network_offset(skb));
2166 }
2167 }
2168
2169 snaplen = skb->len;
2170
2171 res = run_filter(skb, sk, snaplen);
2172 if (!res)
2173 goto drop_n_restore;
2174
2175 if (skb->ip_summed == CHECKSUM_PARTIAL)
2176 status |= TP_STATUS_CSUMNOTREADY;
2177 else if (skb->pkt_type != PACKET_OUTGOING &&
2178 (skb->ip_summed == CHECKSUM_COMPLETE ||
2179 skb_csum_unnecessary(skb)))
2180 status |= TP_STATUS_CSUM_VALID;
2181
2182 if (snaplen > res)
2183 snaplen = res;
2184
2185 if (sk->sk_type == SOCK_DGRAM) {
2186 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2187 po->tp_reserve;
2188 } else {
2189 unsigned int maclen = skb_network_offset(skb);
2190 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2191 (maclen < 16 ? 16 : maclen)) +
2192 po->tp_reserve;
2193 if (po->has_vnet_hdr)
2194 netoff += sizeof(struct virtio_net_hdr);
2195 macoff = netoff - maclen;
2196 }
2197 if (po->tp_version <= TPACKET_V2) {
2198 if (macoff + snaplen > po->rx_ring.frame_size) {
2199 if (po->copy_thresh &&
2200 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2201 if (skb_shared(skb)) {
2202 copy_skb = skb_clone(skb, GFP_ATOMIC);
2203 } else {
2204 copy_skb = skb_get(skb);
2205 skb_head = skb->data;
2206 }
2207 if (copy_skb)
2208 skb_set_owner_r(copy_skb, sk);
2209 }
2210 snaplen = po->rx_ring.frame_size - macoff;
2211 if ((int)snaplen < 0)
2212 snaplen = 0;
2213 }
2214 } else if (unlikely(macoff + snaplen >
2215 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2216 u32 nval;
2217
2218 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2219 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2220 snaplen, nval, macoff);
2221 snaplen = nval;
2222 if (unlikely((int)snaplen < 0)) {
2223 snaplen = 0;
2224 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2225 }
2226 }
2227 spin_lock(&sk->sk_receive_queue.lock);
2228 h.raw = packet_current_rx_frame(po, skb,
2229 TP_STATUS_KERNEL, (macoff+snaplen));
2230 if (!h.raw)
2231 goto drop_n_account;
2232 if (po->tp_version <= TPACKET_V2) {
2233 packet_increment_rx_head(po, &po->rx_ring);
2234 /*
2235 * LOSING will be reported till you read the stats,
2236 * because it's COR - Clear On Read.
2237 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2238 * at packet level.
2239 */
2240 if (po->stats.stats1.tp_drops)
2241 status |= TP_STATUS_LOSING;
2242 }
2243 po->stats.stats1.tp_packets++;
2244 if (copy_skb) {
2245 status |= TP_STATUS_COPY;
2246 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2247 }
2248 spin_unlock(&sk->sk_receive_queue.lock);
2249
2250 if (po->has_vnet_hdr) {
2251 if (virtio_net_hdr_from_skb(skb, h.raw + macoff -
2252 sizeof(struct virtio_net_hdr),
2253 vio_le(), true)) {
2254 spin_lock(&sk->sk_receive_queue.lock);
2255 goto drop_n_account;
2256 }
2257 }
2258
2259 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2260
2261 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2262 getnstimeofday(&ts);
2263
2264 status |= ts_status;
2265
2266 switch (po->tp_version) {
2267 case TPACKET_V1:
2268 h.h1->tp_len = skb->len;
2269 h.h1->tp_snaplen = snaplen;
2270 h.h1->tp_mac = macoff;
2271 h.h1->tp_net = netoff;
2272 h.h1->tp_sec = ts.tv_sec;
2273 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2274 hdrlen = sizeof(*h.h1);
2275 break;
2276 case TPACKET_V2:
2277 h.h2->tp_len = skb->len;
2278 h.h2->tp_snaplen = snaplen;
2279 h.h2->tp_mac = macoff;
2280 h.h2->tp_net = netoff;
2281 h.h2->tp_sec = ts.tv_sec;
2282 h.h2->tp_nsec = ts.tv_nsec;
2283 if (skb_vlan_tag_present(skb)) {
2284 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2285 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2286 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2287 } else {
2288 h.h2->tp_vlan_tci = 0;
2289 h.h2->tp_vlan_tpid = 0;
2290 }
2291 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2292 hdrlen = sizeof(*h.h2);
2293 break;
2294 case TPACKET_V3:
2295 /* tp_nxt_offset,vlan are already populated above.
2296 * So DONT clear those fields here
2297 */
2298 h.h3->tp_status |= status;
2299 h.h3->tp_len = skb->len;
2300 h.h3->tp_snaplen = snaplen;
2301 h.h3->tp_mac = macoff;
2302 h.h3->tp_net = netoff;
2303 h.h3->tp_sec = ts.tv_sec;
2304 h.h3->tp_nsec = ts.tv_nsec;
2305 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2306 hdrlen = sizeof(*h.h3);
2307 break;
2308 default:
2309 BUG();
2310 }
2311
2312 sll = h.raw + TPACKET_ALIGN(hdrlen);
2313 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2314 sll->sll_family = AF_PACKET;
2315 sll->sll_hatype = dev->type;
2316 sll->sll_protocol = skb->protocol;
2317 sll->sll_pkttype = skb->pkt_type;
2318 if (unlikely(po->origdev))
2319 sll->sll_ifindex = orig_dev->ifindex;
2320 else
2321 sll->sll_ifindex = dev->ifindex;
2322
2323 smp_mb();
2324
2325#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2326 if (po->tp_version <= TPACKET_V2) {
2327 u8 *start, *end;
2328
2329 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2330 macoff + snaplen);
2331
2332 for (start = h.raw; start < end; start += PAGE_SIZE)
2333 flush_dcache_page(pgv_to_page(start));
2334 }
2335 smp_wmb();
2336#endif
2337
2338 if (po->tp_version <= TPACKET_V2) {
2339 __packet_set_status(po, h.raw, status);
2340 sk->sk_data_ready(sk);
2341 } else {
2342 prb_clear_blk_fill_status(&po->rx_ring);
2343 }
2344
2345drop_n_restore:
2346 if (skb_head != skb->data && skb_shared(skb)) {
2347 skb->data = skb_head;
2348 skb->len = skb_len;
2349 }
2350drop:
2351 if (!is_drop_n_account)
2352 consume_skb(skb);
2353 else
2354 kfree_skb(skb);
2355 return 0;
2356
2357drop_n_account:
2358 is_drop_n_account = true;
2359 po->stats.stats1.tp_drops++;
2360 spin_unlock(&sk->sk_receive_queue.lock);
2361
2362 sk->sk_data_ready(sk);
2363 kfree_skb(copy_skb);
2364 goto drop_n_restore;
2365}
2366
2367static void tpacket_destruct_skb(struct sk_buff *skb)
2368{
2369 struct packet_sock *po = pkt_sk(skb->sk);
2370
2371 if (likely(po->tx_ring.pg_vec)) {
2372 void *ph;
2373 __u32 ts;
2374
2375 ph = skb_shinfo(skb)->destructor_arg;
2376 packet_dec_pending(&po->tx_ring);
2377
2378 ts = __packet_set_timestamp(po, ph, skb);
2379 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2380 }
2381
2382 sock_wfree(skb);
2383}
2384
2385static void tpacket_set_protocol(const struct net_device *dev,
2386 struct sk_buff *skb)
2387{
2388 if (dev->type == ARPHRD_ETHER) {
2389 skb_reset_mac_header(skb);
2390 skb->protocol = eth_hdr(skb)->h_proto;
2391 }
2392}
2393
2394static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2395{
2396 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2397 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2398 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2399 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2400 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2401 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2402 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2403
2404 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2405 return -EINVAL;
2406
2407 return 0;
2408}
2409
2410static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2411 struct virtio_net_hdr *vnet_hdr)
2412{
2413 if (*len < sizeof(*vnet_hdr))
2414 return -EINVAL;
2415 *len -= sizeof(*vnet_hdr);
2416
2417 if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
2418 return -EFAULT;
2419
2420 return __packet_snd_vnet_parse(vnet_hdr, *len);
2421}
2422
2423static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2424 void *frame, struct net_device *dev, void *data, int tp_len,
2425 __be16 proto, unsigned char *addr, int hlen, int copylen,
2426 const struct sockcm_cookie *sockc)
2427{
2428 union tpacket_uhdr ph;
2429 int to_write, offset, len, nr_frags, len_max;
2430 struct socket *sock = po->sk.sk_socket;
2431 struct page *page;
2432 int err;
2433
2434 ph.raw = frame;
2435
2436 skb->protocol = proto;
2437 skb->dev = dev;
2438 skb->priority = po->sk.sk_priority;
2439 skb->mark = po->sk.sk_mark;
2440 sock_tx_timestamp(&po->sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
2441 skb_shinfo(skb)->destructor_arg = ph.raw;
2442
2443 skb_reserve(skb, hlen);
2444 skb_reset_network_header(skb);
2445
2446 to_write = tp_len;
2447
2448 if (sock->type == SOCK_DGRAM) {
2449 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2450 NULL, tp_len);
2451 if (unlikely(err < 0))
2452 return -EINVAL;
2453 } else if (copylen) {
2454 int hdrlen = min_t(int, copylen, tp_len);
2455
2456 skb_push(skb, dev->hard_header_len);
2457 skb_put(skb, copylen - dev->hard_header_len);
2458 err = skb_store_bits(skb, 0, data, hdrlen);
2459 if (unlikely(err))
2460 return err;
2461 if (!dev_validate_header(dev, skb->data, hdrlen))
2462 return -EINVAL;
2463 if (!skb->protocol)
2464 tpacket_set_protocol(dev, skb);
2465
2466 data += hdrlen;
2467 to_write -= hdrlen;
2468 }
2469
2470 offset = offset_in_page(data);
2471 len_max = PAGE_SIZE - offset;
2472 len = ((to_write > len_max) ? len_max : to_write);
2473
2474 skb->data_len = to_write;
2475 skb->len += to_write;
2476 skb->truesize += to_write;
2477 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2478
2479 while (likely(to_write)) {
2480 nr_frags = skb_shinfo(skb)->nr_frags;
2481
2482 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2483 pr_err("Packet exceed the number of skb frags(%lu)\n",
2484 MAX_SKB_FRAGS);
2485 return -EFAULT;
2486 }
2487
2488 page = pgv_to_page(data);
2489 data += len;
2490 flush_dcache_page(page);
2491 get_page(page);
2492 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2493 to_write -= len;
2494 offset = 0;
2495 len_max = PAGE_SIZE;
2496 len = ((to_write > len_max) ? len_max : to_write);
2497 }
2498
2499 skb_probe_transport_header(skb, 0);
2500
2501 return tp_len;
2502}
2503
2504static int tpacket_parse_header(struct packet_sock *po, void *frame,
2505 int size_max, void **data)
2506{
2507 union tpacket_uhdr ph;
2508 int tp_len, off;
2509
2510 ph.raw = frame;
2511
2512 switch (po->tp_version) {
2513 case TPACKET_V2:
2514 tp_len = ph.h2->tp_len;
2515 break;
2516 default:
2517 tp_len = ph.h1->tp_len;
2518 break;
2519 }
2520 if (unlikely(tp_len > size_max)) {
2521 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2522 return -EMSGSIZE;
2523 }
2524
2525 if (unlikely(po->tp_tx_has_off)) {
2526 int off_min, off_max;
2527
2528 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2529 off_max = po->tx_ring.frame_size - tp_len;
2530 if (po->sk.sk_type == SOCK_DGRAM) {
2531 switch (po->tp_version) {
2532 case TPACKET_V2:
2533 off = ph.h2->tp_net;
2534 break;
2535 default:
2536 off = ph.h1->tp_net;
2537 break;
2538 }
2539 } else {
2540 switch (po->tp_version) {
2541 case TPACKET_V2:
2542 off = ph.h2->tp_mac;
2543 break;
2544 default:
2545 off = ph.h1->tp_mac;
2546 break;
2547 }
2548 }
2549 if (unlikely((off < off_min) || (off_max < off)))
2550 return -EINVAL;
2551 } else {
2552 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2553 }
2554
2555 *data = frame + off;
2556 return tp_len;
2557}
2558
2559static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2560{
2561 struct sk_buff *skb;
2562 struct net_device *dev;
2563 struct virtio_net_hdr *vnet_hdr = NULL;
2564 struct sockcm_cookie sockc;
2565 __be16 proto;
2566 int err, reserve = 0;
2567 void *ph;
2568 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2569 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2570 int tp_len, size_max;
2571 unsigned char *addr;
2572 void *data;
2573 int len_sum = 0;
2574 int status = TP_STATUS_AVAILABLE;
2575 int hlen, tlen, copylen = 0;
2576
2577 mutex_lock(&po->pg_vec_lock);
2578
2579 if (likely(saddr == NULL)) {
2580 dev = packet_cached_dev_get(po);
2581 proto = po->num;
2582 addr = NULL;
2583 } else {
2584 err = -EINVAL;
2585 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2586 goto out;
2587 if (msg->msg_namelen < (saddr->sll_halen
2588 + offsetof(struct sockaddr_ll,
2589 sll_addr)))
2590 goto out;
2591 proto = saddr->sll_protocol;
2592 addr = saddr->sll_addr;
2593 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2594 }
2595
2596 sockc.tsflags = po->sk.sk_tsflags;
2597 if (msg->msg_controllen) {
2598 err = sock_cmsg_send(&po->sk, msg, &sockc);
2599 if (unlikely(err))
2600 goto out;
2601 }
2602
2603 err = -ENXIO;
2604 if (unlikely(dev == NULL))
2605 goto out;
2606 err = -ENETDOWN;
2607 if (unlikely(!(dev->flags & IFF_UP)))
2608 goto out_put;
2609
2610 if (po->sk.sk_socket->type == SOCK_RAW)
2611 reserve = dev->hard_header_len;
2612 size_max = po->tx_ring.frame_size
2613 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2614
2615 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2616 size_max = dev->mtu + reserve + VLAN_HLEN;
2617
2618 do {
2619 ph = packet_current_frame(po, &po->tx_ring,
2620 TP_STATUS_SEND_REQUEST);
2621 if (unlikely(ph == NULL)) {
2622 if (need_wait && need_resched())
2623 schedule();
2624 continue;
2625 }
2626
2627 skb = NULL;
2628 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2629 if (tp_len < 0)
2630 goto tpacket_error;
2631
2632 status = TP_STATUS_SEND_REQUEST;
2633 hlen = LL_RESERVED_SPACE(dev);
2634 tlen = dev->needed_tailroom;
2635 if (po->has_vnet_hdr) {
2636 vnet_hdr = data;
2637 data += sizeof(*vnet_hdr);
2638 tp_len -= sizeof(*vnet_hdr);
2639 if (tp_len < 0 ||
2640 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2641 tp_len = -EINVAL;
2642 goto tpacket_error;
2643 }
2644 copylen = __virtio16_to_cpu(vio_le(),
2645 vnet_hdr->hdr_len);
2646 }
2647 copylen = max_t(int, copylen, dev->hard_header_len);
2648 skb = sock_alloc_send_skb(&po->sk,
2649 hlen + tlen + sizeof(struct sockaddr_ll) +
2650 (copylen - dev->hard_header_len),
2651 !need_wait, &err);
2652
2653 if (unlikely(skb == NULL)) {
2654 /* we assume the socket was initially writeable ... */
2655 if (likely(len_sum > 0))
2656 err = len_sum;
2657 goto out_status;
2658 }
2659 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2660 addr, hlen, copylen, &sockc);
2661 if (likely(tp_len >= 0) &&
2662 tp_len > dev->mtu + reserve &&
2663 !po->has_vnet_hdr &&
2664 !packet_extra_vlan_len_allowed(dev, skb))
2665 tp_len = -EMSGSIZE;
2666
2667 if (unlikely(tp_len < 0)) {
2668tpacket_error:
2669 if (po->tp_loss) {
2670 __packet_set_status(po, ph,
2671 TP_STATUS_AVAILABLE);
2672 packet_increment_head(&po->tx_ring);
2673 kfree_skb(skb);
2674 continue;
2675 } else {
2676 status = TP_STATUS_WRONG_FORMAT;
2677 err = tp_len;
2678 goto out_status;
2679 }
2680 }
2681
2682 if (po->has_vnet_hdr && virtio_net_hdr_to_skb(skb, vnet_hdr,
2683 vio_le())) {
2684 tp_len = -EINVAL;
2685 goto tpacket_error;
2686 }
2687
2688 packet_pick_tx_queue(dev, skb);
2689
2690 skb->destructor = tpacket_destruct_skb;
2691 __packet_set_status(po, ph, TP_STATUS_SENDING);
2692 packet_inc_pending(&po->tx_ring);
2693
2694 status = TP_STATUS_SEND_REQUEST;
2695 err = po->xmit(skb);
2696 if (unlikely(err > 0)) {
2697 err = net_xmit_errno(err);
2698 if (err && __packet_get_status(po, ph) ==
2699 TP_STATUS_AVAILABLE) {
2700 /* skb was destructed already */
2701 skb = NULL;
2702 goto out_status;
2703 }
2704 /*
2705 * skb was dropped but not destructed yet;
2706 * let's treat it like congestion or err < 0
2707 */
2708 err = 0;
2709 }
2710 packet_increment_head(&po->tx_ring);
2711 len_sum += tp_len;
2712 } while (likely((ph != NULL) ||
2713 /* Note: packet_read_pending() might be slow if we have
2714 * to call it as it's per_cpu variable, but in fast-path
2715 * we already short-circuit the loop with the first
2716 * condition, and luckily don't have to go that path
2717 * anyway.
2718 */
2719 (need_wait && packet_read_pending(&po->tx_ring))));
2720
2721 err = len_sum;
2722 goto out_put;
2723
2724out_status:
2725 __packet_set_status(po, ph, status);
2726 kfree_skb(skb);
2727out_put:
2728 dev_put(dev);
2729out:
2730 mutex_unlock(&po->pg_vec_lock);
2731 return err;
2732}
2733
2734static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2735 size_t reserve, size_t len,
2736 size_t linear, int noblock,
2737 int *err)
2738{
2739 struct sk_buff *skb;
2740
2741 /* Under a page? Don't bother with paged skb. */
2742 if (prepad + len < PAGE_SIZE || !linear)
2743 linear = len;
2744
2745 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2746 err, 0);
2747 if (!skb)
2748 return NULL;
2749
2750 skb_reserve(skb, reserve);
2751 skb_put(skb, linear);
2752 skb->data_len = len - linear;
2753 skb->len += len - linear;
2754
2755 return skb;
2756}
2757
2758static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2759{
2760 struct sock *sk = sock->sk;
2761 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2762 struct sk_buff *skb;
2763 struct net_device *dev;
2764 __be16 proto;
2765 unsigned char *addr;
2766 int err, reserve = 0;
2767 struct sockcm_cookie sockc;
2768 struct virtio_net_hdr vnet_hdr = { 0 };
2769 int offset = 0;
2770 struct packet_sock *po = pkt_sk(sk);
2771 int hlen, tlen, linear;
2772 int extra_len = 0;
2773
2774 /*
2775 * Get and verify the address.
2776 */
2777
2778 if (likely(saddr == NULL)) {
2779 dev = packet_cached_dev_get(po);
2780 proto = po->num;
2781 addr = NULL;
2782 } else {
2783 err = -EINVAL;
2784 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2785 goto out;
2786 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2787 goto out;
2788 proto = saddr->sll_protocol;
2789 addr = saddr->sll_addr;
2790 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2791 }
2792
2793 err = -ENXIO;
2794 if (unlikely(dev == NULL))
2795 goto out_unlock;
2796 err = -ENETDOWN;
2797 if (unlikely(!(dev->flags & IFF_UP)))
2798 goto out_unlock;
2799
2800 sockc.tsflags = sk->sk_tsflags;
2801 sockc.mark = sk->sk_mark;
2802 if (msg->msg_controllen) {
2803 err = sock_cmsg_send(sk, msg, &sockc);
2804 if (unlikely(err))
2805 goto out_unlock;
2806 }
2807
2808 if (sock->type == SOCK_RAW)
2809 reserve = dev->hard_header_len;
2810 if (po->has_vnet_hdr) {
2811 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2812 if (err)
2813 goto out_unlock;
2814 }
2815
2816 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2817 if (!netif_supports_nofcs(dev)) {
2818 err = -EPROTONOSUPPORT;
2819 goto out_unlock;
2820 }
2821 extra_len = 4; /* We're doing our own CRC */
2822 }
2823
2824 err = -EMSGSIZE;
2825 if (!vnet_hdr.gso_type &&
2826 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2827 goto out_unlock;
2828
2829 err = -ENOBUFS;
2830 hlen = LL_RESERVED_SPACE(dev);
2831 tlen = dev->needed_tailroom;
2832 linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len);
2833 linear = max(linear, min_t(int, len, dev->hard_header_len));
2834 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear,
2835 msg->msg_flags & MSG_DONTWAIT, &err);
2836 if (skb == NULL)
2837 goto out_unlock;
2838
2839 skb_set_network_header(skb, reserve);
2840
2841 err = -EINVAL;
2842 if (sock->type == SOCK_DGRAM) {
2843 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2844 if (unlikely(offset < 0))
2845 goto out_free;
2846 }
2847
2848 /* Returns -EFAULT on error */
2849 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2850 if (err)
2851 goto out_free;
2852
2853 if (sock->type == SOCK_RAW &&
2854 !dev_validate_header(dev, skb->data, len)) {
2855 err = -EINVAL;
2856 goto out_free;
2857 }
2858
2859 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
2860
2861 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2862 !packet_extra_vlan_len_allowed(dev, skb)) {
2863 err = -EMSGSIZE;
2864 goto out_free;
2865 }
2866
2867 skb->protocol = proto;
2868 skb->dev = dev;
2869 skb->priority = sk->sk_priority;
2870 skb->mark = sockc.mark;
2871
2872 packet_pick_tx_queue(dev, skb);
2873
2874 if (po->has_vnet_hdr) {
2875 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
2876 if (err)
2877 goto out_free;
2878 len += sizeof(vnet_hdr);
2879 }
2880
2881 skb_probe_transport_header(skb, reserve);
2882
2883 if (unlikely(extra_len == 4))
2884 skb->no_fcs = 1;
2885
2886 err = po->xmit(skb);
2887 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2888 goto out_unlock;
2889
2890 dev_put(dev);
2891
2892 return len;
2893
2894out_free:
2895 kfree_skb(skb);
2896out_unlock:
2897 if (dev)
2898 dev_put(dev);
2899out:
2900 return err;
2901}
2902
2903static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2904{
2905 struct sock *sk = sock->sk;
2906 struct packet_sock *po = pkt_sk(sk);
2907
2908 if (po->tx_ring.pg_vec)
2909 return tpacket_snd(po, msg);
2910 else
2911 return packet_snd(sock, msg, len);
2912}
2913
2914/*
2915 * Close a PACKET socket. This is fairly simple. We immediately go
2916 * to 'closed' state and remove our protocol entry in the device list.
2917 */
2918
2919static int packet_release(struct socket *sock)
2920{
2921 struct sock *sk = sock->sk;
2922 struct packet_sock *po;
2923 struct packet_fanout *f;
2924 struct net *net;
2925 union tpacket_req_u req_u;
2926
2927 if (!sk)
2928 return 0;
2929
2930 net = sock_net(sk);
2931 po = pkt_sk(sk);
2932
2933 mutex_lock(&net->packet.sklist_lock);
2934 sk_del_node_init_rcu(sk);
2935 mutex_unlock(&net->packet.sklist_lock);
2936
2937 preempt_disable();
2938 sock_prot_inuse_add(net, sk->sk_prot, -1);
2939 preempt_enable();
2940
2941 spin_lock(&po->bind_lock);
2942 unregister_prot_hook(sk, false);
2943 packet_cached_dev_reset(po);
2944
2945 if (po->prot_hook.dev) {
2946 dev_put(po->prot_hook.dev);
2947 po->prot_hook.dev = NULL;
2948 }
2949 spin_unlock(&po->bind_lock);
2950
2951 packet_flush_mclist(sk);
2952
2953 if (po->rx_ring.pg_vec) {
2954 memset(&req_u, 0, sizeof(req_u));
2955 packet_set_ring(sk, &req_u, 1, 0);
2956 }
2957
2958 if (po->tx_ring.pg_vec) {
2959 memset(&req_u, 0, sizeof(req_u));
2960 packet_set_ring(sk, &req_u, 1, 1);
2961 }
2962
2963 f = fanout_release(sk);
2964
2965 synchronize_net();
2966
2967 if (f) {
2968 fanout_release_data(f);
2969 kfree(f);
2970 }
2971 /*
2972 * Now the socket is dead. No more input will appear.
2973 */
2974 sock_orphan(sk);
2975 sock->sk = NULL;
2976
2977 /* Purge queues */
2978
2979 skb_queue_purge(&sk->sk_receive_queue);
2980 packet_free_pending(po);
2981 sk_refcnt_debug_release(sk);
2982
2983 sock_put(sk);
2984 return 0;
2985}
2986
2987/*
2988 * Attach a packet hook.
2989 */
2990
2991static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
2992 __be16 proto)
2993{
2994 struct packet_sock *po = pkt_sk(sk);
2995 struct net_device *dev_curr;
2996 __be16 proto_curr;
2997 bool need_rehook;
2998 struct net_device *dev = NULL;
2999 int ret = 0;
3000 bool unlisted = false;
3001
3002 if (po->fanout)
3003 return -EINVAL;
3004
3005 lock_sock(sk);
3006 spin_lock(&po->bind_lock);
3007 rcu_read_lock();
3008
3009 if (name) {
3010 dev = dev_get_by_name_rcu(sock_net(sk), name);
3011 if (!dev) {
3012 ret = -ENODEV;
3013 goto out_unlock;
3014 }
3015 } else if (ifindex) {
3016 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3017 if (!dev) {
3018 ret = -ENODEV;
3019 goto out_unlock;
3020 }
3021 }
3022
3023 if (dev)
3024 dev_hold(dev);
3025
3026 proto_curr = po->prot_hook.type;
3027 dev_curr = po->prot_hook.dev;
3028
3029 need_rehook = proto_curr != proto || dev_curr != dev;
3030
3031 if (need_rehook) {
3032 if (po->running) {
3033 rcu_read_unlock();
3034 __unregister_prot_hook(sk, true);
3035 rcu_read_lock();
3036 dev_curr = po->prot_hook.dev;
3037 if (dev)
3038 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3039 dev->ifindex);
3040 }
3041
3042 po->num = proto;
3043 po->prot_hook.type = proto;
3044
3045 if (unlikely(unlisted)) {
3046 dev_put(dev);
3047 po->prot_hook.dev = NULL;
3048 po->ifindex = -1;
3049 packet_cached_dev_reset(po);
3050 } else {
3051 po->prot_hook.dev = dev;
3052 po->ifindex = dev ? dev->ifindex : 0;
3053 packet_cached_dev_assign(po, dev);
3054 }
3055 }
3056 if (dev_curr)
3057 dev_put(dev_curr);
3058
3059 if (proto == 0 || !need_rehook)
3060 goto out_unlock;
3061
3062 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3063 register_prot_hook(sk);
3064 } else {
3065 sk->sk_err = ENETDOWN;
3066 if (!sock_flag(sk, SOCK_DEAD))
3067 sk->sk_error_report(sk);
3068 }
3069
3070out_unlock:
3071 rcu_read_unlock();
3072 spin_unlock(&po->bind_lock);
3073 release_sock(sk);
3074 return ret;
3075}
3076
3077/*
3078 * Bind a packet socket to a device
3079 */
3080
3081static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3082 int addr_len)
3083{
3084 struct sock *sk = sock->sk;
3085 char name[sizeof(uaddr->sa_data) + 1];
3086
3087 /*
3088 * Check legality
3089 */
3090
3091 if (addr_len != sizeof(struct sockaddr))
3092 return -EINVAL;
3093 /* uaddr->sa_data comes from the userspace, it's not guaranteed to be
3094 * zero-terminated.
3095 */
3096 memcpy(name, uaddr->sa_data, sizeof(uaddr->sa_data));
3097 name[sizeof(uaddr->sa_data)] = 0;
3098
3099 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3100}
3101
3102static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3103{
3104 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3105 struct sock *sk = sock->sk;
3106
3107 /*
3108 * Check legality
3109 */
3110
3111 if (addr_len < sizeof(struct sockaddr_ll))
3112 return -EINVAL;
3113 if (sll->sll_family != AF_PACKET)
3114 return -EINVAL;
3115
3116 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3117 sll->sll_protocol ? : pkt_sk(sk)->num);
3118}
3119
3120static struct proto packet_proto = {
3121 .name = "PACKET",
3122 .owner = THIS_MODULE,
3123 .obj_size = sizeof(struct packet_sock),
3124};
3125
3126/*
3127 * Create a packet of type SOCK_PACKET.
3128 */
3129
3130static int packet_create(struct net *net, struct socket *sock, int protocol,
3131 int kern)
3132{
3133 struct sock *sk;
3134 struct packet_sock *po;
3135 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3136 int err;
3137
3138 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3139 return -EPERM;
3140 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3141 sock->type != SOCK_PACKET)
3142 return -ESOCKTNOSUPPORT;
3143
3144 sock->state = SS_UNCONNECTED;
3145
3146 err = -ENOBUFS;
3147 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3148 if (sk == NULL)
3149 goto out;
3150
3151 sock->ops = &packet_ops;
3152 if (sock->type == SOCK_PACKET)
3153 sock->ops = &packet_ops_spkt;
3154
3155 sock_init_data(sock, sk);
3156
3157 po = pkt_sk(sk);
3158 sk->sk_family = PF_PACKET;
3159 po->num = proto;
3160 po->xmit = dev_queue_xmit;
3161
3162 err = packet_alloc_pending(po);
3163 if (err)
3164 goto out2;
3165
3166 packet_cached_dev_reset(po);
3167
3168 sk->sk_destruct = packet_sock_destruct;
3169 sk_refcnt_debug_inc(sk);
3170
3171 /*
3172 * Attach a protocol block
3173 */
3174
3175 spin_lock_init(&po->bind_lock);
3176 mutex_init(&po->pg_vec_lock);
3177 po->rollover = NULL;
3178 po->prot_hook.func = packet_rcv;
3179
3180 if (sock->type == SOCK_PACKET)
3181 po->prot_hook.func = packet_rcv_spkt;
3182
3183 po->prot_hook.af_packet_priv = sk;
3184
3185 if (proto) {
3186 po->prot_hook.type = proto;
3187 register_prot_hook(sk);
3188 }
3189
3190 mutex_lock(&net->packet.sklist_lock);
3191 sk_add_node_rcu(sk, &net->packet.sklist);
3192 mutex_unlock(&net->packet.sklist_lock);
3193
3194 preempt_disable();
3195 sock_prot_inuse_add(net, &packet_proto, 1);
3196 preempt_enable();
3197
3198 return 0;
3199out2:
3200 sk_free(sk);
3201out:
3202 return err;
3203}
3204
3205/*
3206 * Pull a packet from our receive queue and hand it to the user.
3207 * If necessary we block.
3208 */
3209
3210static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3211 int flags)
3212{
3213 struct sock *sk = sock->sk;
3214 struct sk_buff *skb;
3215 int copied, err;
3216 int vnet_hdr_len = 0;
3217 unsigned int origlen = 0;
3218
3219 err = -EINVAL;
3220 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3221 goto out;
3222
3223#if 0
3224 /* What error should we return now? EUNATTACH? */
3225 if (pkt_sk(sk)->ifindex < 0)
3226 return -ENODEV;
3227#endif
3228
3229 if (flags & MSG_ERRQUEUE) {
3230 err = sock_recv_errqueue(sk, msg, len,
3231 SOL_PACKET, PACKET_TX_TIMESTAMP);
3232 goto out;
3233 }
3234
3235 /*
3236 * Call the generic datagram receiver. This handles all sorts
3237 * of horrible races and re-entrancy so we can forget about it
3238 * in the protocol layers.
3239 *
3240 * Now it will return ENETDOWN, if device have just gone down,
3241 * but then it will block.
3242 */
3243
3244 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3245
3246 /*
3247 * An error occurred so return it. Because skb_recv_datagram()
3248 * handles the blocking we don't see and worry about blocking
3249 * retries.
3250 */
3251
3252 if (skb == NULL)
3253 goto out;
3254
3255 if (pkt_sk(sk)->pressure)
3256 packet_rcv_has_room(pkt_sk(sk), NULL);
3257
3258 if (pkt_sk(sk)->has_vnet_hdr) {
3259 err = packet_rcv_vnet(msg, skb, &len);
3260 if (err)
3261 goto out_free;
3262 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3263 }
3264
3265 /* You lose any data beyond the buffer you gave. If it worries
3266 * a user program they can ask the device for its MTU
3267 * anyway.
3268 */
3269 copied = skb->len;
3270 if (copied > len) {
3271 copied = len;
3272 msg->msg_flags |= MSG_TRUNC;
3273 }
3274
3275 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3276 if (err)
3277 goto out_free;
3278
3279 if (sock->type != SOCK_PACKET) {
3280 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3281
3282 /* Original length was stored in sockaddr_ll fields */
3283 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3284 sll->sll_family = AF_PACKET;
3285 sll->sll_protocol = skb->protocol;
3286 }
3287
3288 sock_recv_ts_and_drops(msg, sk, skb);
3289
3290 if (msg->msg_name) {
3291 /* If the address length field is there to be filled
3292 * in, we fill it in now.
3293 */
3294 if (sock->type == SOCK_PACKET) {
3295 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3296 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3297 } else {
3298 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3299
3300 msg->msg_namelen = sll->sll_halen +
3301 offsetof(struct sockaddr_ll, sll_addr);
3302 }
3303 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3304 msg->msg_namelen);
3305 }
3306
3307 if (pkt_sk(sk)->auxdata) {
3308 struct tpacket_auxdata aux;
3309
3310 aux.tp_status = TP_STATUS_USER;
3311 if (skb->ip_summed == CHECKSUM_PARTIAL)
3312 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3313 else if (skb->pkt_type != PACKET_OUTGOING &&
3314 (skb->ip_summed == CHECKSUM_COMPLETE ||
3315 skb_csum_unnecessary(skb)))
3316 aux.tp_status |= TP_STATUS_CSUM_VALID;
3317
3318 aux.tp_len = origlen;
3319 aux.tp_snaplen = skb->len;
3320 aux.tp_mac = 0;
3321 aux.tp_net = skb_network_offset(skb);
3322 if (skb_vlan_tag_present(skb)) {
3323 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3324 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3325 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3326 } else {
3327 aux.tp_vlan_tci = 0;
3328 aux.tp_vlan_tpid = 0;
3329 }
3330 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3331 }
3332
3333 /*
3334 * Free or return the buffer as appropriate. Again this
3335 * hides all the races and re-entrancy issues from us.
3336 */
3337 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3338
3339out_free:
3340 skb_free_datagram(sk, skb);
3341out:
3342 return err;
3343}
3344
3345static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3346 int *uaddr_len, int peer)
3347{
3348 struct net_device *dev;
3349 struct sock *sk = sock->sk;
3350
3351 if (peer)
3352 return -EOPNOTSUPP;
3353
3354 uaddr->sa_family = AF_PACKET;
3355 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3356 rcu_read_lock();
3357 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3358 if (dev)
3359 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3360 rcu_read_unlock();
3361 *uaddr_len = sizeof(*uaddr);
3362
3363 return 0;
3364}
3365
3366static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3367 int *uaddr_len, int peer)
3368{
3369 struct net_device *dev;
3370 struct sock *sk = sock->sk;
3371 struct packet_sock *po = pkt_sk(sk);
3372 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3373
3374 if (peer)
3375 return -EOPNOTSUPP;
3376
3377 sll->sll_family = AF_PACKET;
3378 sll->sll_ifindex = po->ifindex;
3379 sll->sll_protocol = po->num;
3380 sll->sll_pkttype = 0;
3381 rcu_read_lock();
3382 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3383 if (dev) {
3384 sll->sll_hatype = dev->type;
3385 sll->sll_halen = dev->addr_len;
3386 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3387 } else {
3388 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3389 sll->sll_halen = 0;
3390 }
3391 rcu_read_unlock();
3392 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3393
3394 return 0;
3395}
3396
3397static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3398 int what)
3399{
3400 switch (i->type) {
3401 case PACKET_MR_MULTICAST:
3402 if (i->alen != dev->addr_len)
3403 return -EINVAL;
3404 if (what > 0)
3405 return dev_mc_add(dev, i->addr);
3406 else
3407 return dev_mc_del(dev, i->addr);
3408 break;
3409 case PACKET_MR_PROMISC:
3410 return dev_set_promiscuity(dev, what);
3411 case PACKET_MR_ALLMULTI:
3412 return dev_set_allmulti(dev, what);
3413 case PACKET_MR_UNICAST:
3414 if (i->alen != dev->addr_len)
3415 return -EINVAL;
3416 if (what > 0)
3417 return dev_uc_add(dev, i->addr);
3418 else
3419 return dev_uc_del(dev, i->addr);
3420 break;
3421 default:
3422 break;
3423 }
3424 return 0;
3425}
3426
3427static void packet_dev_mclist_delete(struct net_device *dev,
3428 struct packet_mclist **mlp)
3429{
3430 struct packet_mclist *ml;
3431
3432 while ((ml = *mlp) != NULL) {
3433 if (ml->ifindex == dev->ifindex) {
3434 packet_dev_mc(dev, ml, -1);
3435 *mlp = ml->next;
3436 kfree(ml);
3437 } else
3438 mlp = &ml->next;
3439 }
3440}
3441
3442static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3443{
3444 struct packet_sock *po = pkt_sk(sk);
3445 struct packet_mclist *ml, *i;
3446 struct net_device *dev;
3447 int err;
3448
3449 rtnl_lock();
3450
3451 err = -ENODEV;
3452 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3453 if (!dev)
3454 goto done;
3455
3456 err = -EINVAL;
3457 if (mreq->mr_alen > dev->addr_len)
3458 goto done;
3459
3460 err = -ENOBUFS;
3461 i = kmalloc(sizeof(*i), GFP_KERNEL);
3462 if (i == NULL)
3463 goto done;
3464
3465 err = 0;
3466 for (ml = po->mclist; ml; ml = ml->next) {
3467 if (ml->ifindex == mreq->mr_ifindex &&
3468 ml->type == mreq->mr_type &&
3469 ml->alen == mreq->mr_alen &&
3470 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3471 ml->count++;
3472 /* Free the new element ... */
3473 kfree(i);
3474 goto done;
3475 }
3476 }
3477
3478 i->type = mreq->mr_type;
3479 i->ifindex = mreq->mr_ifindex;
3480 i->alen = mreq->mr_alen;
3481 memcpy(i->addr, mreq->mr_address, i->alen);
3482 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3483 i->count = 1;
3484 i->next = po->mclist;
3485 po->mclist = i;
3486 err = packet_dev_mc(dev, i, 1);
3487 if (err) {
3488 po->mclist = i->next;
3489 kfree(i);
3490 }
3491
3492done:
3493 rtnl_unlock();
3494 return err;
3495}
3496
3497static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3498{
3499 struct packet_mclist *ml, **mlp;
3500
3501 rtnl_lock();
3502
3503 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3504 if (ml->ifindex == mreq->mr_ifindex &&
3505 ml->type == mreq->mr_type &&
3506 ml->alen == mreq->mr_alen &&
3507 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3508 if (--ml->count == 0) {
3509 struct net_device *dev;
3510 *mlp = ml->next;
3511 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3512 if (dev)
3513 packet_dev_mc(dev, ml, -1);
3514 kfree(ml);
3515 }
3516 break;
3517 }
3518 }
3519 rtnl_unlock();
3520 return 0;
3521}
3522
3523static void packet_flush_mclist(struct sock *sk)
3524{
3525 struct packet_sock *po = pkt_sk(sk);
3526 struct packet_mclist *ml;
3527
3528 if (!po->mclist)
3529 return;
3530
3531 rtnl_lock();
3532 while ((ml = po->mclist) != NULL) {
3533 struct net_device *dev;
3534
3535 po->mclist = ml->next;
3536 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3537 if (dev != NULL)
3538 packet_dev_mc(dev, ml, -1);
3539 kfree(ml);
3540 }
3541 rtnl_unlock();
3542}
3543
3544static int
3545packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3546{
3547 struct sock *sk = sock->sk;
3548 struct packet_sock *po = pkt_sk(sk);
3549 int ret;
3550
3551 if (level != SOL_PACKET)
3552 return -ENOPROTOOPT;
3553
3554 switch (optname) {
3555 case PACKET_ADD_MEMBERSHIP:
3556 case PACKET_DROP_MEMBERSHIP:
3557 {
3558 struct packet_mreq_max mreq;
3559 int len = optlen;
3560 memset(&mreq, 0, sizeof(mreq));
3561 if (len < sizeof(struct packet_mreq))
3562 return -EINVAL;
3563 if (len > sizeof(mreq))
3564 len = sizeof(mreq);
3565 if (copy_from_user(&mreq, optval, len))
3566 return -EFAULT;
3567 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3568 return -EINVAL;
3569 if (optname == PACKET_ADD_MEMBERSHIP)
3570 ret = packet_mc_add(sk, &mreq);
3571 else
3572 ret = packet_mc_drop(sk, &mreq);
3573 return ret;
3574 }
3575
3576 case PACKET_RX_RING:
3577 case PACKET_TX_RING:
3578 {
3579 union tpacket_req_u req_u;
3580 int len;
3581
3582 switch (po->tp_version) {
3583 case TPACKET_V1:
3584 case TPACKET_V2:
3585 len = sizeof(req_u.req);
3586 break;
3587 case TPACKET_V3:
3588 default:
3589 len = sizeof(req_u.req3);
3590 break;
3591 }
3592 if (optlen < len)
3593 return -EINVAL;
3594 if (copy_from_user(&req_u.req, optval, len))
3595 return -EFAULT;
3596 return packet_set_ring(sk, &req_u, 0,
3597 optname == PACKET_TX_RING);
3598 }
3599 case PACKET_COPY_THRESH:
3600 {
3601 int val;
3602
3603 if (optlen != sizeof(val))
3604 return -EINVAL;
3605 if (copy_from_user(&val, optval, sizeof(val)))
3606 return -EFAULT;
3607
3608 pkt_sk(sk)->copy_thresh = val;
3609 return 0;
3610 }
3611 case PACKET_VERSION:
3612 {
3613 int val;
3614
3615 if (optlen != sizeof(val))
3616 return -EINVAL;
3617 if (copy_from_user(&val, optval, sizeof(val)))
3618 return -EFAULT;
3619 switch (val) {
3620 case TPACKET_V1:
3621 case TPACKET_V2:
3622 case TPACKET_V3:
3623 break;
3624 default:
3625 return -EINVAL;
3626 }
3627 lock_sock(sk);
3628 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3629 ret = -EBUSY;
3630 } else {
3631 po->tp_version = val;
3632 ret = 0;
3633 }
3634 release_sock(sk);
3635 return ret;
3636 }
3637 case PACKET_RESERVE:
3638 {
3639 unsigned int val;
3640
3641 if (optlen != sizeof(val))
3642 return -EINVAL;
3643 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3644 return -EBUSY;
3645 if (copy_from_user(&val, optval, sizeof(val)))
3646 return -EFAULT;
3647 po->tp_reserve = val;
3648 return 0;
3649 }
3650 case PACKET_LOSS:
3651 {
3652 unsigned int val;
3653
3654 if (optlen != sizeof(val))
3655 return -EINVAL;
3656 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3657 return -EBUSY;
3658 if (copy_from_user(&val, optval, sizeof(val)))
3659 return -EFAULT;
3660 po->tp_loss = !!val;
3661 return 0;
3662 }
3663 case PACKET_AUXDATA:
3664 {
3665 int val;
3666
3667 if (optlen < sizeof(val))
3668 return -EINVAL;
3669 if (copy_from_user(&val, optval, sizeof(val)))
3670 return -EFAULT;
3671
3672 po->auxdata = !!val;
3673 return 0;
3674 }
3675 case PACKET_ORIGDEV:
3676 {
3677 int val;
3678
3679 if (optlen < sizeof(val))
3680 return -EINVAL;
3681 if (copy_from_user(&val, optval, sizeof(val)))
3682 return -EFAULT;
3683
3684 po->origdev = !!val;
3685 return 0;
3686 }
3687 case PACKET_VNET_HDR:
3688 {
3689 int val;
3690
3691 if (sock->type != SOCK_RAW)
3692 return -EINVAL;
3693 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3694 return -EBUSY;
3695 if (optlen < sizeof(val))
3696 return -EINVAL;
3697 if (copy_from_user(&val, optval, sizeof(val)))
3698 return -EFAULT;
3699
3700 po->has_vnet_hdr = !!val;
3701 return 0;
3702 }
3703 case PACKET_TIMESTAMP:
3704 {
3705 int val;
3706
3707 if (optlen != sizeof(val))
3708 return -EINVAL;
3709 if (copy_from_user(&val, optval, sizeof(val)))
3710 return -EFAULT;
3711
3712 po->tp_tstamp = val;
3713 return 0;
3714 }
3715 case PACKET_FANOUT:
3716 {
3717 int val;
3718
3719 if (optlen != sizeof(val))
3720 return -EINVAL;
3721 if (copy_from_user(&val, optval, sizeof(val)))
3722 return -EFAULT;
3723
3724 return fanout_add(sk, val & 0xffff, val >> 16);
3725 }
3726 case PACKET_FANOUT_DATA:
3727 {
3728 if (!po->fanout)
3729 return -EINVAL;
3730
3731 return fanout_set_data(po, optval, optlen);
3732 }
3733 case PACKET_TX_HAS_OFF:
3734 {
3735 unsigned int val;
3736
3737 if (optlen != sizeof(val))
3738 return -EINVAL;
3739 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3740 return -EBUSY;
3741 if (copy_from_user(&val, optval, sizeof(val)))
3742 return -EFAULT;
3743 po->tp_tx_has_off = !!val;
3744 return 0;
3745 }
3746 case PACKET_QDISC_BYPASS:
3747 {
3748 int val;
3749
3750 if (optlen != sizeof(val))
3751 return -EINVAL;
3752 if (copy_from_user(&val, optval, sizeof(val)))
3753 return -EFAULT;
3754
3755 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3756 return 0;
3757 }
3758 default:
3759 return -ENOPROTOOPT;
3760 }
3761}
3762
3763static int packet_getsockopt(struct socket *sock, int level, int optname,
3764 char __user *optval, int __user *optlen)
3765{
3766 int len;
3767 int val, lv = sizeof(val);
3768 struct sock *sk = sock->sk;
3769 struct packet_sock *po = pkt_sk(sk);
3770 void *data = &val;
3771 union tpacket_stats_u st;
3772 struct tpacket_rollover_stats rstats;
3773
3774 if (level != SOL_PACKET)
3775 return -ENOPROTOOPT;
3776
3777 if (get_user(len, optlen))
3778 return -EFAULT;
3779
3780 if (len < 0)
3781 return -EINVAL;
3782
3783 switch (optname) {
3784 case PACKET_STATISTICS:
3785 spin_lock_bh(&sk->sk_receive_queue.lock);
3786 memcpy(&st, &po->stats, sizeof(st));
3787 memset(&po->stats, 0, sizeof(po->stats));
3788 spin_unlock_bh(&sk->sk_receive_queue.lock);
3789
3790 if (po->tp_version == TPACKET_V3) {
3791 lv = sizeof(struct tpacket_stats_v3);
3792 st.stats3.tp_packets += st.stats3.tp_drops;
3793 data = &st.stats3;
3794 } else {
3795 lv = sizeof(struct tpacket_stats);
3796 st.stats1.tp_packets += st.stats1.tp_drops;
3797 data = &st.stats1;
3798 }
3799
3800 break;
3801 case PACKET_AUXDATA:
3802 val = po->auxdata;
3803 break;
3804 case PACKET_ORIGDEV:
3805 val = po->origdev;
3806 break;
3807 case PACKET_VNET_HDR:
3808 val = po->has_vnet_hdr;
3809 break;
3810 case PACKET_VERSION:
3811 val = po->tp_version;
3812 break;
3813 case PACKET_HDRLEN:
3814 if (len > sizeof(int))
3815 len = sizeof(int);
3816 if (copy_from_user(&val, optval, len))
3817 return -EFAULT;
3818 switch (val) {
3819 case TPACKET_V1:
3820 val = sizeof(struct tpacket_hdr);
3821 break;
3822 case TPACKET_V2:
3823 val = sizeof(struct tpacket2_hdr);
3824 break;
3825 case TPACKET_V3:
3826 val = sizeof(struct tpacket3_hdr);
3827 break;
3828 default:
3829 return -EINVAL;
3830 }
3831 break;
3832 case PACKET_RESERVE:
3833 val = po->tp_reserve;
3834 break;
3835 case PACKET_LOSS:
3836 val = po->tp_loss;
3837 break;
3838 case PACKET_TIMESTAMP:
3839 val = po->tp_tstamp;
3840 break;
3841 case PACKET_FANOUT:
3842 val = (po->fanout ?
3843 ((u32)po->fanout->id |
3844 ((u32)po->fanout->type << 16) |
3845 ((u32)po->fanout->flags << 24)) :
3846 0);
3847 break;
3848 case PACKET_ROLLOVER_STATS:
3849 if (!po->rollover)
3850 return -EINVAL;
3851 rstats.tp_all = atomic_long_read(&po->rollover->num);
3852 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3853 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3854 data = &rstats;
3855 lv = sizeof(rstats);
3856 break;
3857 case PACKET_TX_HAS_OFF:
3858 val = po->tp_tx_has_off;
3859 break;
3860 case PACKET_QDISC_BYPASS:
3861 val = packet_use_direct_xmit(po);
3862 break;
3863 default:
3864 return -ENOPROTOOPT;
3865 }
3866
3867 if (len > lv)
3868 len = lv;
3869 if (put_user(len, optlen))
3870 return -EFAULT;
3871 if (copy_to_user(optval, data, len))
3872 return -EFAULT;
3873 return 0;
3874}
3875
3876
3877#ifdef CONFIG_COMPAT
3878static int compat_packet_setsockopt(struct socket *sock, int level, int optname,
3879 char __user *optval, unsigned int optlen)
3880{
3881 struct packet_sock *po = pkt_sk(sock->sk);
3882
3883 if (level != SOL_PACKET)
3884 return -ENOPROTOOPT;
3885
3886 if (optname == PACKET_FANOUT_DATA &&
3887 po->fanout && po->fanout->type == PACKET_FANOUT_CBPF) {
3888 optval = (char __user *)get_compat_bpf_fprog(optval);
3889 if (!optval)
3890 return -EFAULT;
3891 optlen = sizeof(struct sock_fprog);
3892 }
3893
3894 return packet_setsockopt(sock, level, optname, optval, optlen);
3895}
3896#endif
3897
3898static int packet_notifier(struct notifier_block *this,
3899 unsigned long msg, void *ptr)
3900{
3901 struct sock *sk;
3902 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3903 struct net *net = dev_net(dev);
3904
3905 rcu_read_lock();
3906 sk_for_each_rcu(sk, &net->packet.sklist) {
3907 struct packet_sock *po = pkt_sk(sk);
3908
3909 switch (msg) {
3910 case NETDEV_UNREGISTER:
3911 if (po->mclist)
3912 packet_dev_mclist_delete(dev, &po->mclist);
3913 /* fallthrough */
3914
3915 case NETDEV_DOWN:
3916 if (dev->ifindex == po->ifindex) {
3917 spin_lock(&po->bind_lock);
3918 if (po->running) {
3919 __unregister_prot_hook(sk, false);
3920 sk->sk_err = ENETDOWN;
3921 if (!sock_flag(sk, SOCK_DEAD))
3922 sk->sk_error_report(sk);
3923 }
3924 if (msg == NETDEV_UNREGISTER) {
3925 packet_cached_dev_reset(po);
3926 po->ifindex = -1;
3927 if (po->prot_hook.dev)
3928 dev_put(po->prot_hook.dev);
3929 po->prot_hook.dev = NULL;
3930 }
3931 spin_unlock(&po->bind_lock);
3932 }
3933 break;
3934 case NETDEV_UP:
3935 if (dev->ifindex == po->ifindex) {
3936 spin_lock(&po->bind_lock);
3937 if (po->num)
3938 register_prot_hook(sk);
3939 spin_unlock(&po->bind_lock);
3940 }
3941 break;
3942 }
3943 }
3944 rcu_read_unlock();
3945 return NOTIFY_DONE;
3946}
3947
3948
3949static int packet_ioctl(struct socket *sock, unsigned int cmd,
3950 unsigned long arg)
3951{
3952 struct sock *sk = sock->sk;
3953
3954 switch (cmd) {
3955 case SIOCOUTQ:
3956 {
3957 int amount = sk_wmem_alloc_get(sk);
3958
3959 return put_user(amount, (int __user *)arg);
3960 }
3961 case SIOCINQ:
3962 {
3963 struct sk_buff *skb;
3964 int amount = 0;
3965
3966 spin_lock_bh(&sk->sk_receive_queue.lock);
3967 skb = skb_peek(&sk->sk_receive_queue);
3968 if (skb)
3969 amount = skb->len;
3970 spin_unlock_bh(&sk->sk_receive_queue.lock);
3971 return put_user(amount, (int __user *)arg);
3972 }
3973 case SIOCGSTAMP:
3974 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3975 case SIOCGSTAMPNS:
3976 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3977
3978#ifdef CONFIG_INET
3979 case SIOCADDRT:
3980 case SIOCDELRT:
3981 case SIOCDARP:
3982 case SIOCGARP:
3983 case SIOCSARP:
3984 case SIOCGIFADDR:
3985 case SIOCSIFADDR:
3986 case SIOCGIFBRDADDR:
3987 case SIOCSIFBRDADDR:
3988 case SIOCGIFNETMASK:
3989 case SIOCSIFNETMASK:
3990 case SIOCGIFDSTADDR:
3991 case SIOCSIFDSTADDR:
3992 case SIOCSIFFLAGS:
3993 return inet_dgram_ops.ioctl(sock, cmd, arg);
3994#endif
3995
3996 default:
3997 return -ENOIOCTLCMD;
3998 }
3999 return 0;
4000}
4001
4002static unsigned int packet_poll(struct file *file, struct socket *sock,
4003 poll_table *wait)
4004{
4005 struct sock *sk = sock->sk;
4006 struct packet_sock *po = pkt_sk(sk);
4007 unsigned int mask = datagram_poll(file, sock, wait);
4008
4009 spin_lock_bh(&sk->sk_receive_queue.lock);
4010 if (po->rx_ring.pg_vec) {
4011 if (!packet_previous_rx_frame(po, &po->rx_ring,
4012 TP_STATUS_KERNEL))
4013 mask |= POLLIN | POLLRDNORM;
4014 }
4015 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
4016 po->pressure = 0;
4017 spin_unlock_bh(&sk->sk_receive_queue.lock);
4018 spin_lock_bh(&sk->sk_write_queue.lock);
4019 if (po->tx_ring.pg_vec) {
4020 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4021 mask |= POLLOUT | POLLWRNORM;
4022 }
4023 spin_unlock_bh(&sk->sk_write_queue.lock);
4024 return mask;
4025}
4026
4027
4028/* Dirty? Well, I still did not learn better way to account
4029 * for user mmaps.
4030 */
4031
4032static void packet_mm_open(struct vm_area_struct *vma)
4033{
4034 struct file *file = vma->vm_file;
4035 struct socket *sock = file->private_data;
4036 struct sock *sk = sock->sk;
4037
4038 if (sk)
4039 atomic_inc(&pkt_sk(sk)->mapped);
4040}
4041
4042static void packet_mm_close(struct vm_area_struct *vma)
4043{
4044 struct file *file = vma->vm_file;
4045 struct socket *sock = file->private_data;
4046 struct sock *sk = sock->sk;
4047
4048 if (sk)
4049 atomic_dec(&pkt_sk(sk)->mapped);
4050}
4051
4052static const struct vm_operations_struct packet_mmap_ops = {
4053 .open = packet_mm_open,
4054 .close = packet_mm_close,
4055};
4056
4057static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4058 unsigned int len)
4059{
4060 int i;
4061
4062 for (i = 0; i < len; i++) {
4063 if (likely(pg_vec[i].buffer)) {
4064 if (is_vmalloc_addr(pg_vec[i].buffer))
4065 vfree(pg_vec[i].buffer);
4066 else
4067 free_pages((unsigned long)pg_vec[i].buffer,
4068 order);
4069 pg_vec[i].buffer = NULL;
4070 }
4071 }
4072 kfree(pg_vec);
4073}
4074
4075static char *alloc_one_pg_vec_page(unsigned long order)
4076{
4077 char *buffer;
4078 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4079 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4080
4081 buffer = (char *) __get_free_pages(gfp_flags, order);
4082 if (buffer)
4083 return buffer;
4084
4085 /* __get_free_pages failed, fall back to vmalloc */
4086 buffer = vzalloc((1 << order) * PAGE_SIZE);
4087 if (buffer)
4088 return buffer;
4089
4090 /* vmalloc failed, lets dig into swap here */
4091 gfp_flags &= ~__GFP_NORETRY;
4092 buffer = (char *) __get_free_pages(gfp_flags, order);
4093 if (buffer)
4094 return buffer;
4095
4096 /* complete and utter failure */
4097 return NULL;
4098}
4099
4100static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4101{
4102 unsigned int block_nr = req->tp_block_nr;
4103 struct pgv *pg_vec;
4104 int i;
4105
4106 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4107 if (unlikely(!pg_vec))
4108 goto out;
4109
4110 for (i = 0; i < block_nr; i++) {
4111 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4112 if (unlikely(!pg_vec[i].buffer))
4113 goto out_free_pgvec;
4114 }
4115
4116out:
4117 return pg_vec;
4118
4119out_free_pgvec:
4120 free_pg_vec(pg_vec, order, block_nr);
4121 pg_vec = NULL;
4122 goto out;
4123}
4124
4125static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4126 int closing, int tx_ring)
4127{
4128 struct pgv *pg_vec = NULL;
4129 struct packet_sock *po = pkt_sk(sk);
4130 int was_running, order = 0;
4131 struct packet_ring_buffer *rb;
4132 struct sk_buff_head *rb_queue;
4133 __be16 num;
4134 int err = -EINVAL;
4135 /* Added to avoid minimal code churn */
4136 struct tpacket_req *req = &req_u->req;
4137
4138 lock_sock(sk);
4139 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
4140 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
4141 net_warn_ratelimited("Tx-ring is not supported.\n");
4142 goto out;
4143 }
4144
4145 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4146 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4147
4148 err = -EBUSY;
4149 if (!closing) {
4150 if (atomic_read(&po->mapped))
4151 goto out;
4152 if (packet_read_pending(rb))
4153 goto out;
4154 }
4155
4156 if (req->tp_block_nr) {
4157 /* Sanity tests and some calculations */
4158 err = -EBUSY;
4159 if (unlikely(rb->pg_vec))
4160 goto out;
4161
4162 switch (po->tp_version) {
4163 case TPACKET_V1:
4164 po->tp_hdrlen = TPACKET_HDRLEN;
4165 break;
4166 case TPACKET_V2:
4167 po->tp_hdrlen = TPACKET2_HDRLEN;
4168 break;
4169 case TPACKET_V3:
4170 po->tp_hdrlen = TPACKET3_HDRLEN;
4171 break;
4172 }
4173
4174 err = -EINVAL;
4175 if (unlikely((int)req->tp_block_size <= 0))
4176 goto out;
4177 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4178 goto out;
4179 if (po->tp_version >= TPACKET_V3 &&
4180 req->tp_block_size <=
4181 BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv))
4182 goto out;
4183 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
4184 po->tp_reserve))
4185 goto out;
4186 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4187 goto out;
4188
4189 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4190 if (unlikely(rb->frames_per_block == 0))
4191 goto out;
4192 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4193 req->tp_frame_nr))
4194 goto out;
4195
4196 err = -ENOMEM;
4197 order = get_order(req->tp_block_size);
4198 pg_vec = alloc_pg_vec(req, order);
4199 if (unlikely(!pg_vec))
4200 goto out;
4201 switch (po->tp_version) {
4202 case TPACKET_V3:
4203 /* Transmit path is not supported. We checked
4204 * it above but just being paranoid
4205 */
4206 if (!tx_ring)
4207 init_prb_bdqc(po, rb, pg_vec, req_u);
4208 break;
4209 default:
4210 break;
4211 }
4212 }
4213 /* Done */
4214 else {
4215 err = -EINVAL;
4216 if (unlikely(req->tp_frame_nr))
4217 goto out;
4218 }
4219
4220
4221 /* Detach socket from network */
4222 spin_lock(&po->bind_lock);
4223 was_running = po->running;
4224 num = po->num;
4225 if (was_running) {
4226 po->num = 0;
4227 __unregister_prot_hook(sk, false);
4228 }
4229 spin_unlock(&po->bind_lock);
4230
4231 synchronize_net();
4232
4233 err = -EBUSY;
4234 mutex_lock(&po->pg_vec_lock);
4235 if (closing || atomic_read(&po->mapped) == 0) {
4236 err = 0;
4237 spin_lock_bh(&rb_queue->lock);
4238 swap(rb->pg_vec, pg_vec);
4239 rb->frame_max = (req->tp_frame_nr - 1);
4240 rb->head = 0;
4241 rb->frame_size = req->tp_frame_size;
4242 spin_unlock_bh(&rb_queue->lock);
4243
4244 swap(rb->pg_vec_order, order);
4245 swap(rb->pg_vec_len, req->tp_block_nr);
4246
4247 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4248 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4249 tpacket_rcv : packet_rcv;
4250 skb_queue_purge(rb_queue);
4251 if (atomic_read(&po->mapped))
4252 pr_err("packet_mmap: vma is busy: %d\n",
4253 atomic_read(&po->mapped));
4254 }
4255 mutex_unlock(&po->pg_vec_lock);
4256
4257 spin_lock(&po->bind_lock);
4258 if (was_running) {
4259 po->num = num;
4260 register_prot_hook(sk);
4261 }
4262 spin_unlock(&po->bind_lock);
4263 if (closing && (po->tp_version > TPACKET_V2)) {
4264 /* Because we don't support block-based V3 on tx-ring */
4265 if (!tx_ring)
4266 prb_shutdown_retire_blk_timer(po, rb_queue);
4267 }
4268
4269 if (pg_vec)
4270 free_pg_vec(pg_vec, order, req->tp_block_nr);
4271out:
4272 release_sock(sk);
4273 return err;
4274}
4275
4276static int packet_mmap(struct file *file, struct socket *sock,
4277 struct vm_area_struct *vma)
4278{
4279 struct sock *sk = sock->sk;
4280 struct packet_sock *po = pkt_sk(sk);
4281 unsigned long size, expected_size;
4282 struct packet_ring_buffer *rb;
4283 unsigned long start;
4284 int err = -EINVAL;
4285 int i;
4286
4287 if (vma->vm_pgoff)
4288 return -EINVAL;
4289
4290 mutex_lock(&po->pg_vec_lock);
4291
4292 expected_size = 0;
4293 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4294 if (rb->pg_vec) {
4295 expected_size += rb->pg_vec_len
4296 * rb->pg_vec_pages
4297 * PAGE_SIZE;
4298 }
4299 }
4300
4301 if (expected_size == 0)
4302 goto out;
4303
4304 size = vma->vm_end - vma->vm_start;
4305 if (size != expected_size)
4306 goto out;
4307
4308 start = vma->vm_start;
4309 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4310 if (rb->pg_vec == NULL)
4311 continue;
4312
4313 for (i = 0; i < rb->pg_vec_len; i++) {
4314 struct page *page;
4315 void *kaddr = rb->pg_vec[i].buffer;
4316 int pg_num;
4317
4318 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4319 page = pgv_to_page(kaddr);
4320 err = vm_insert_page(vma, start, page);
4321 if (unlikely(err))
4322 goto out;
4323 start += PAGE_SIZE;
4324 kaddr += PAGE_SIZE;
4325 }
4326 }
4327 }
4328
4329 atomic_inc(&po->mapped);
4330 vma->vm_ops = &packet_mmap_ops;
4331 err = 0;
4332
4333out:
4334 mutex_unlock(&po->pg_vec_lock);
4335 return err;
4336}
4337
4338static const struct proto_ops packet_ops_spkt = {
4339 .family = PF_PACKET,
4340 .owner = THIS_MODULE,
4341 .release = packet_release,
4342 .bind = packet_bind_spkt,
4343 .connect = sock_no_connect,
4344 .socketpair = sock_no_socketpair,
4345 .accept = sock_no_accept,
4346 .getname = packet_getname_spkt,
4347 .poll = datagram_poll,
4348 .ioctl = packet_ioctl,
4349 .listen = sock_no_listen,
4350 .shutdown = sock_no_shutdown,
4351 .setsockopt = sock_no_setsockopt,
4352 .getsockopt = sock_no_getsockopt,
4353 .sendmsg = packet_sendmsg_spkt,
4354 .recvmsg = packet_recvmsg,
4355 .mmap = sock_no_mmap,
4356 .sendpage = sock_no_sendpage,
4357};
4358
4359static const struct proto_ops packet_ops = {
4360 .family = PF_PACKET,
4361 .owner = THIS_MODULE,
4362 .release = packet_release,
4363 .bind = packet_bind,
4364 .connect = sock_no_connect,
4365 .socketpair = sock_no_socketpair,
4366 .accept = sock_no_accept,
4367 .getname = packet_getname,
4368 .poll = packet_poll,
4369 .ioctl = packet_ioctl,
4370 .listen = sock_no_listen,
4371 .shutdown = sock_no_shutdown,
4372 .setsockopt = packet_setsockopt,
4373 .getsockopt = packet_getsockopt,
4374#ifdef CONFIG_COMPAT
4375 .compat_setsockopt = compat_packet_setsockopt,
4376#endif
4377 .sendmsg = packet_sendmsg,
4378 .recvmsg = packet_recvmsg,
4379 .mmap = packet_mmap,
4380 .sendpage = sock_no_sendpage,
4381};
4382
4383static const struct net_proto_family packet_family_ops = {
4384 .family = PF_PACKET,
4385 .create = packet_create,
4386 .owner = THIS_MODULE,
4387};
4388
4389static struct notifier_block packet_netdev_notifier = {
4390 .notifier_call = packet_notifier,
4391};
4392
4393#ifdef CONFIG_PROC_FS
4394
4395static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4396 __acquires(RCU)
4397{
4398 struct net *net = seq_file_net(seq);
4399
4400 rcu_read_lock();
4401 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4402}
4403
4404static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4405{
4406 struct net *net = seq_file_net(seq);
4407 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4408}
4409
4410static void packet_seq_stop(struct seq_file *seq, void *v)
4411 __releases(RCU)
4412{
4413 rcu_read_unlock();
4414}
4415
4416static int packet_seq_show(struct seq_file *seq, void *v)
4417{
4418 if (v == SEQ_START_TOKEN)
4419 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4420 else {
4421 struct sock *s = sk_entry(v);
4422 const struct packet_sock *po = pkt_sk(s);
4423
4424 seq_printf(seq,
4425 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4426 s,
4427 atomic_read(&s->sk_refcnt),
4428 s->sk_type,
4429 ntohs(po->num),
4430 po->ifindex,
4431 po->running,
4432 atomic_read(&s->sk_rmem_alloc),
4433 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4434 sock_i_ino(s));
4435 }
4436
4437 return 0;
4438}
4439
4440static const struct seq_operations packet_seq_ops = {
4441 .start = packet_seq_start,
4442 .next = packet_seq_next,
4443 .stop = packet_seq_stop,
4444 .show = packet_seq_show,
4445};
4446
4447static int packet_seq_open(struct inode *inode, struct file *file)
4448{
4449 return seq_open_net(inode, file, &packet_seq_ops,
4450 sizeof(struct seq_net_private));
4451}
4452
4453static const struct file_operations packet_seq_fops = {
4454 .owner = THIS_MODULE,
4455 .open = packet_seq_open,
4456 .read = seq_read,
4457 .llseek = seq_lseek,
4458 .release = seq_release_net,
4459};
4460
4461#endif
4462
4463static int __net_init packet_net_init(struct net *net)
4464{
4465 mutex_init(&net->packet.sklist_lock);
4466 INIT_HLIST_HEAD(&net->packet.sklist);
4467
4468 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4469 return -ENOMEM;
4470
4471 return 0;
4472}
4473
4474static void __net_exit packet_net_exit(struct net *net)
4475{
4476 remove_proc_entry("packet", net->proc_net);
4477}
4478
4479static struct pernet_operations packet_net_ops = {
4480 .init = packet_net_init,
4481 .exit = packet_net_exit,
4482};
4483
4484
4485static void __exit packet_exit(void)
4486{
4487 unregister_netdevice_notifier(&packet_netdev_notifier);
4488 unregister_pernet_subsys(&packet_net_ops);
4489 sock_unregister(PF_PACKET);
4490 proto_unregister(&packet_proto);
4491}
4492
4493static int __init packet_init(void)
4494{
4495 int rc = proto_register(&packet_proto, 0);
4496
4497 if (rc != 0)
4498 goto out;
4499
4500 sock_register(&packet_family_ops);
4501 register_pernet_subsys(&packet_net_ops);
4502 register_netdevice_notifier(&packet_netdev_notifier);
4503out:
4504 return rc;
4505}
4506
4507module_init(packet_init);
4508module_exit(packet_exit);
4509MODULE_LICENSE("GPL");
4510MODULE_ALIAS_NETPROTO(PF_PACKET);