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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 *
44 * This program is free software; you can redistribute it and/or
45 * modify it under the terms of the GNU General Public License
46 * as published by the Free Software Foundation; either version
47 * 2 of the License, or (at your option) any later version.
48 *
49 */
50
51#include <linux/types.h>
52#include <linux/mm.h>
53#include <linux/capability.h>
54#include <linux/fcntl.h>
55#include <linux/socket.h>
56#include <linux/in.h>
57#include <linux/inet.h>
58#include <linux/netdevice.h>
59#include <linux/if_packet.h>
60#include <linux/wireless.h>
61#include <linux/kernel.h>
62#include <linux/kmod.h>
63#include <linux/slab.h>
64#include <linux/vmalloc.h>
65#include <net/net_namespace.h>
66#include <net/ip.h>
67#include <net/protocol.h>
68#include <linux/skbuff.h>
69#include <net/sock.h>
70#include <linux/errno.h>
71#include <linux/timer.h>
72#include <asm/system.h>
73#include <asm/uaccess.h>
74#include <asm/ioctls.h>
75#include <asm/page.h>
76#include <asm/cacheflush.h>
77#include <asm/io.h>
78#include <linux/proc_fs.h>
79#include <linux/seq_file.h>
80#include <linux/poll.h>
81#include <linux/module.h>
82#include <linux/init.h>
83#include <linux/mutex.h>
84#include <linux/if_vlan.h>
85#include <linux/virtio_net.h>
86#include <linux/errqueue.h>
87#include <linux/net_tstamp.h>
88
89#ifdef CONFIG_INET
90#include <net/inet_common.h>
91#endif
92
93/*
94 Assumptions:
95 - if device has no dev->hard_header routine, it adds and removes ll header
96 inside itself. In this case ll header is invisible outside of device,
97 but higher levels still should reserve dev->hard_header_len.
98 Some devices are enough clever to reallocate skb, when header
99 will not fit to reserved space (tunnel), another ones are silly
100 (PPP).
101 - packet socket receives packets with pulled ll header,
102 so that SOCK_RAW should push it back.
103
104On receive:
105-----------
106
107Incoming, dev->hard_header!=NULL
108 mac_header -> ll header
109 data -> data
110
111Outgoing, dev->hard_header!=NULL
112 mac_header -> ll header
113 data -> ll header
114
115Incoming, dev->hard_header==NULL
116 mac_header -> UNKNOWN position. It is very likely, that it points to ll
117 header. PPP makes it, that is wrong, because introduce
118 assymetry between rx and tx paths.
119 data -> data
120
121Outgoing, dev->hard_header==NULL
122 mac_header -> data. ll header is still not built!
123 data -> data
124
125Resume
126 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
127
128
129On transmit:
130------------
131
132dev->hard_header != NULL
133 mac_header -> ll header
134 data -> ll header
135
136dev->hard_header == NULL (ll header is added by device, we cannot control it)
137 mac_header -> data
138 data -> data
139
140 We should set nh.raw on output to correct posistion,
141 packet classifier depends on it.
142 */
143
144/* Private packet socket structures. */
145
146struct packet_mclist {
147 struct packet_mclist *next;
148 int ifindex;
149 int count;
150 unsigned short type;
151 unsigned short alen;
152 unsigned char addr[MAX_ADDR_LEN];
153};
154/* identical to struct packet_mreq except it has
155 * a longer address field.
156 */
157struct packet_mreq_max {
158 int mr_ifindex;
159 unsigned short mr_type;
160 unsigned short mr_alen;
161 unsigned char mr_address[MAX_ADDR_LEN];
162};
163
164static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
165 int closing, int tx_ring);
166
167struct pgv {
168 char *buffer;
169};
170
171struct packet_ring_buffer {
172 struct pgv *pg_vec;
173 unsigned int head;
174 unsigned int frames_per_block;
175 unsigned int frame_size;
176 unsigned int frame_max;
177
178 unsigned int pg_vec_order;
179 unsigned int pg_vec_pages;
180 unsigned int pg_vec_len;
181
182 atomic_t pending;
183};
184
185struct packet_sock;
186static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
187
188static void packet_flush_mclist(struct sock *sk);
189
190struct packet_fanout;
191struct packet_sock {
192 /* struct sock has to be the first member of packet_sock */
193 struct sock sk;
194 struct packet_fanout *fanout;
195 struct tpacket_stats stats;
196 struct packet_ring_buffer rx_ring;
197 struct packet_ring_buffer tx_ring;
198 int copy_thresh;
199 spinlock_t bind_lock;
200 struct mutex pg_vec_lock;
201 unsigned int running:1, /* prot_hook is attached*/
202 auxdata:1,
203 origdev:1,
204 has_vnet_hdr:1;
205 int ifindex; /* bound device */
206 __be16 num;
207 struct packet_mclist *mclist;
208 atomic_t mapped;
209 enum tpacket_versions tp_version;
210 unsigned int tp_hdrlen;
211 unsigned int tp_reserve;
212 unsigned int tp_loss:1;
213 unsigned int tp_tstamp;
214 struct packet_type prot_hook ____cacheline_aligned_in_smp;
215};
216
217#define PACKET_FANOUT_MAX 256
218
219struct packet_fanout {
220#ifdef CONFIG_NET_NS
221 struct net *net;
222#endif
223 unsigned int num_members;
224 u16 id;
225 u8 type;
226 u8 defrag;
227 atomic_t rr_cur;
228 struct list_head list;
229 struct sock *arr[PACKET_FANOUT_MAX];
230 spinlock_t lock;
231 atomic_t sk_ref;
232 struct packet_type prot_hook ____cacheline_aligned_in_smp;
233};
234
235struct packet_skb_cb {
236 unsigned int origlen;
237 union {
238 struct sockaddr_pkt pkt;
239 struct sockaddr_ll ll;
240 } sa;
241};
242
243#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
244
245static inline struct packet_sock *pkt_sk(struct sock *sk)
246{
247 return (struct packet_sock *)sk;
248}
249
250static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
251static void __fanout_link(struct sock *sk, struct packet_sock *po);
252
253/* register_prot_hook must be invoked with the po->bind_lock held,
254 * or from a context in which asynchronous accesses to the packet
255 * socket is not possible (packet_create()).
256 */
257static void register_prot_hook(struct sock *sk)
258{
259 struct packet_sock *po = pkt_sk(sk);
260 if (!po->running) {
261 if (po->fanout)
262 __fanout_link(sk, po);
263 else
264 dev_add_pack(&po->prot_hook);
265 sock_hold(sk);
266 po->running = 1;
267 }
268}
269
270/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
271 * held. If the sync parameter is true, we will temporarily drop
272 * the po->bind_lock and do a synchronize_net to make sure no
273 * asynchronous packet processing paths still refer to the elements
274 * of po->prot_hook. If the sync parameter is false, it is the
275 * callers responsibility to take care of this.
276 */
277static void __unregister_prot_hook(struct sock *sk, bool sync)
278{
279 struct packet_sock *po = pkt_sk(sk);
280
281 po->running = 0;
282 if (po->fanout)
283 __fanout_unlink(sk, po);
284 else
285 __dev_remove_pack(&po->prot_hook);
286 __sock_put(sk);
287
288 if (sync) {
289 spin_unlock(&po->bind_lock);
290 synchronize_net();
291 spin_lock(&po->bind_lock);
292 }
293}
294
295static void unregister_prot_hook(struct sock *sk, bool sync)
296{
297 struct packet_sock *po = pkt_sk(sk);
298
299 if (po->running)
300 __unregister_prot_hook(sk, sync);
301}
302
303static inline __pure struct page *pgv_to_page(void *addr)
304{
305 if (is_vmalloc_addr(addr))
306 return vmalloc_to_page(addr);
307 return virt_to_page(addr);
308}
309
310static void __packet_set_status(struct packet_sock *po, void *frame, int status)
311{
312 union {
313 struct tpacket_hdr *h1;
314 struct tpacket2_hdr *h2;
315 void *raw;
316 } h;
317
318 h.raw = frame;
319 switch (po->tp_version) {
320 case TPACKET_V1:
321 h.h1->tp_status = status;
322 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
323 break;
324 case TPACKET_V2:
325 h.h2->tp_status = status;
326 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
327 break;
328 default:
329 pr_err("TPACKET version not supported\n");
330 BUG();
331 }
332
333 smp_wmb();
334}
335
336static int __packet_get_status(struct packet_sock *po, void *frame)
337{
338 union {
339 struct tpacket_hdr *h1;
340 struct tpacket2_hdr *h2;
341 void *raw;
342 } h;
343
344 smp_rmb();
345
346 h.raw = frame;
347 switch (po->tp_version) {
348 case TPACKET_V1:
349 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
350 return h.h1->tp_status;
351 case TPACKET_V2:
352 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
353 return h.h2->tp_status;
354 default:
355 pr_err("TPACKET version not supported\n");
356 BUG();
357 return 0;
358 }
359}
360
361static void *packet_lookup_frame(struct packet_sock *po,
362 struct packet_ring_buffer *rb,
363 unsigned int position,
364 int status)
365{
366 unsigned int pg_vec_pos, frame_offset;
367 union {
368 struct tpacket_hdr *h1;
369 struct tpacket2_hdr *h2;
370 void *raw;
371 } h;
372
373 pg_vec_pos = position / rb->frames_per_block;
374 frame_offset = position % rb->frames_per_block;
375
376 h.raw = rb->pg_vec[pg_vec_pos].buffer +
377 (frame_offset * rb->frame_size);
378
379 if (status != __packet_get_status(po, h.raw))
380 return NULL;
381
382 return h.raw;
383}
384
385static inline void *packet_current_frame(struct packet_sock *po,
386 struct packet_ring_buffer *rb,
387 int status)
388{
389 return packet_lookup_frame(po, rb, rb->head, status);
390}
391
392static inline void *packet_previous_frame(struct packet_sock *po,
393 struct packet_ring_buffer *rb,
394 int status)
395{
396 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
397 return packet_lookup_frame(po, rb, previous, status);
398}
399
400static inline void packet_increment_head(struct packet_ring_buffer *buff)
401{
402 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
403}
404
405static void packet_sock_destruct(struct sock *sk)
406{
407 skb_queue_purge(&sk->sk_error_queue);
408
409 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
410 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
411
412 if (!sock_flag(sk, SOCK_DEAD)) {
413 pr_err("Attempt to release alive packet socket: %p\n", sk);
414 return;
415 }
416
417 sk_refcnt_debug_dec(sk);
418}
419
420static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
421{
422 int x = atomic_read(&f->rr_cur) + 1;
423
424 if (x >= num)
425 x = 0;
426
427 return x;
428}
429
430static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
431{
432 u32 idx, hash = skb->rxhash;
433
434 idx = ((u64)hash * num) >> 32;
435
436 return f->arr[idx];
437}
438
439static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
440{
441 int cur, old;
442
443 cur = atomic_read(&f->rr_cur);
444 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
445 fanout_rr_next(f, num))) != cur)
446 cur = old;
447 return f->arr[cur];
448}
449
450static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
451{
452 unsigned int cpu = smp_processor_id();
453
454 return f->arr[cpu % num];
455}
456
457static struct sk_buff *fanout_check_defrag(struct sk_buff *skb)
458{
459#ifdef CONFIG_INET
460 const struct iphdr *iph;
461 u32 len;
462
463 if (skb->protocol != htons(ETH_P_IP))
464 return skb;
465
466 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
467 return skb;
468
469 iph = ip_hdr(skb);
470 if (iph->ihl < 5 || iph->version != 4)
471 return skb;
472 if (!pskb_may_pull(skb, iph->ihl*4))
473 return skb;
474 iph = ip_hdr(skb);
475 len = ntohs(iph->tot_len);
476 if (skb->len < len || len < (iph->ihl * 4))
477 return skb;
478
479 if (ip_is_fragment(ip_hdr(skb))) {
480 skb = skb_share_check(skb, GFP_ATOMIC);
481 if (skb) {
482 if (pskb_trim_rcsum(skb, len))
483 return skb;
484 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
485 if (ip_defrag(skb, IP_DEFRAG_AF_PACKET))
486 return NULL;
487 skb->rxhash = 0;
488 }
489 }
490#endif
491 return skb;
492}
493
494static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
495 struct packet_type *pt, struct net_device *orig_dev)
496{
497 struct packet_fanout *f = pt->af_packet_priv;
498 unsigned int num = f->num_members;
499 struct packet_sock *po;
500 struct sock *sk;
501
502 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
503 !num) {
504 kfree_skb(skb);
505 return 0;
506 }
507
508 switch (f->type) {
509 case PACKET_FANOUT_HASH:
510 default:
511 if (f->defrag) {
512 skb = fanout_check_defrag(skb);
513 if (!skb)
514 return 0;
515 }
516 skb_get_rxhash(skb);
517 sk = fanout_demux_hash(f, skb, num);
518 break;
519 case PACKET_FANOUT_LB:
520 sk = fanout_demux_lb(f, skb, num);
521 break;
522 case PACKET_FANOUT_CPU:
523 sk = fanout_demux_cpu(f, skb, num);
524 break;
525 }
526
527 po = pkt_sk(sk);
528
529 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
530}
531
532static DEFINE_MUTEX(fanout_mutex);
533static LIST_HEAD(fanout_list);
534
535static void __fanout_link(struct sock *sk, struct packet_sock *po)
536{
537 struct packet_fanout *f = po->fanout;
538
539 spin_lock(&f->lock);
540 f->arr[f->num_members] = sk;
541 smp_wmb();
542 f->num_members++;
543 spin_unlock(&f->lock);
544}
545
546static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
547{
548 struct packet_fanout *f = po->fanout;
549 int i;
550
551 spin_lock(&f->lock);
552 for (i = 0; i < f->num_members; i++) {
553 if (f->arr[i] == sk)
554 break;
555 }
556 BUG_ON(i >= f->num_members);
557 f->arr[i] = f->arr[f->num_members - 1];
558 f->num_members--;
559 spin_unlock(&f->lock);
560}
561
562static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
563{
564 struct packet_sock *po = pkt_sk(sk);
565 struct packet_fanout *f, *match;
566 u8 type = type_flags & 0xff;
567 u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
568 int err;
569
570 switch (type) {
571 case PACKET_FANOUT_HASH:
572 case PACKET_FANOUT_LB:
573 case PACKET_FANOUT_CPU:
574 break;
575 default:
576 return -EINVAL;
577 }
578
579 if (!po->running)
580 return -EINVAL;
581
582 if (po->fanout)
583 return -EALREADY;
584
585 mutex_lock(&fanout_mutex);
586 match = NULL;
587 list_for_each_entry(f, &fanout_list, list) {
588 if (f->id == id &&
589 read_pnet(&f->net) == sock_net(sk)) {
590 match = f;
591 break;
592 }
593 }
594 err = -EINVAL;
595 if (match && match->defrag != defrag)
596 goto out;
597 if (!match) {
598 err = -ENOMEM;
599 match = kzalloc(sizeof(*match), GFP_KERNEL);
600 if (!match)
601 goto out;
602 write_pnet(&match->net, sock_net(sk));
603 match->id = id;
604 match->type = type;
605 match->defrag = defrag;
606 atomic_set(&match->rr_cur, 0);
607 INIT_LIST_HEAD(&match->list);
608 spin_lock_init(&match->lock);
609 atomic_set(&match->sk_ref, 0);
610 match->prot_hook.type = po->prot_hook.type;
611 match->prot_hook.dev = po->prot_hook.dev;
612 match->prot_hook.func = packet_rcv_fanout;
613 match->prot_hook.af_packet_priv = match;
614 dev_add_pack(&match->prot_hook);
615 list_add(&match->list, &fanout_list);
616 }
617 err = -EINVAL;
618 if (match->type == type &&
619 match->prot_hook.type == po->prot_hook.type &&
620 match->prot_hook.dev == po->prot_hook.dev) {
621 err = -ENOSPC;
622 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
623 __dev_remove_pack(&po->prot_hook);
624 po->fanout = match;
625 atomic_inc(&match->sk_ref);
626 __fanout_link(sk, po);
627 err = 0;
628 }
629 }
630out:
631 mutex_unlock(&fanout_mutex);
632 return err;
633}
634
635static void fanout_release(struct sock *sk)
636{
637 struct packet_sock *po = pkt_sk(sk);
638 struct packet_fanout *f;
639
640 f = po->fanout;
641 if (!f)
642 return;
643
644 po->fanout = NULL;
645
646 mutex_lock(&fanout_mutex);
647 if (atomic_dec_and_test(&f->sk_ref)) {
648 list_del(&f->list);
649 dev_remove_pack(&f->prot_hook);
650 kfree(f);
651 }
652 mutex_unlock(&fanout_mutex);
653}
654
655static const struct proto_ops packet_ops;
656
657static const struct proto_ops packet_ops_spkt;
658
659static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
660 struct packet_type *pt, struct net_device *orig_dev)
661{
662 struct sock *sk;
663 struct sockaddr_pkt *spkt;
664
665 /*
666 * When we registered the protocol we saved the socket in the data
667 * field for just this event.
668 */
669
670 sk = pt->af_packet_priv;
671
672 /*
673 * Yank back the headers [hope the device set this
674 * right or kerboom...]
675 *
676 * Incoming packets have ll header pulled,
677 * push it back.
678 *
679 * For outgoing ones skb->data == skb_mac_header(skb)
680 * so that this procedure is noop.
681 */
682
683 if (skb->pkt_type == PACKET_LOOPBACK)
684 goto out;
685
686 if (!net_eq(dev_net(dev), sock_net(sk)))
687 goto out;
688
689 skb = skb_share_check(skb, GFP_ATOMIC);
690 if (skb == NULL)
691 goto oom;
692
693 /* drop any routing info */
694 skb_dst_drop(skb);
695
696 /* drop conntrack reference */
697 nf_reset(skb);
698
699 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
700
701 skb_push(skb, skb->data - skb_mac_header(skb));
702
703 /*
704 * The SOCK_PACKET socket receives _all_ frames.
705 */
706
707 spkt->spkt_family = dev->type;
708 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
709 spkt->spkt_protocol = skb->protocol;
710
711 /*
712 * Charge the memory to the socket. This is done specifically
713 * to prevent sockets using all the memory up.
714 */
715
716 if (sock_queue_rcv_skb(sk, skb) == 0)
717 return 0;
718
719out:
720 kfree_skb(skb);
721oom:
722 return 0;
723}
724
725
726/*
727 * Output a raw packet to a device layer. This bypasses all the other
728 * protocol layers and you must therefore supply it with a complete frame
729 */
730
731static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
732 struct msghdr *msg, size_t len)
733{
734 struct sock *sk = sock->sk;
735 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
736 struct sk_buff *skb = NULL;
737 struct net_device *dev;
738 __be16 proto = 0;
739 int err;
740
741 /*
742 * Get and verify the address.
743 */
744
745 if (saddr) {
746 if (msg->msg_namelen < sizeof(struct sockaddr))
747 return -EINVAL;
748 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
749 proto = saddr->spkt_protocol;
750 } else
751 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
752
753 /*
754 * Find the device first to size check it
755 */
756
757 saddr->spkt_device[13] = 0;
758retry:
759 rcu_read_lock();
760 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
761 err = -ENODEV;
762 if (dev == NULL)
763 goto out_unlock;
764
765 err = -ENETDOWN;
766 if (!(dev->flags & IFF_UP))
767 goto out_unlock;
768
769 /*
770 * You may not queue a frame bigger than the mtu. This is the lowest level
771 * raw protocol and you must do your own fragmentation at this level.
772 */
773
774 err = -EMSGSIZE;
775 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
776 goto out_unlock;
777
778 if (!skb) {
779 size_t reserved = LL_RESERVED_SPACE(dev);
780 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
781
782 rcu_read_unlock();
783 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
784 if (skb == NULL)
785 return -ENOBUFS;
786 /* FIXME: Save some space for broken drivers that write a hard
787 * header at transmission time by themselves. PPP is the notable
788 * one here. This should really be fixed at the driver level.
789 */
790 skb_reserve(skb, reserved);
791 skb_reset_network_header(skb);
792
793 /* Try to align data part correctly */
794 if (hhlen) {
795 skb->data -= hhlen;
796 skb->tail -= hhlen;
797 if (len < hhlen)
798 skb_reset_network_header(skb);
799 }
800 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
801 if (err)
802 goto out_free;
803 goto retry;
804 }
805
806 if (len > (dev->mtu + dev->hard_header_len)) {
807 /* Earlier code assumed this would be a VLAN pkt,
808 * double-check this now that we have the actual
809 * packet in hand.
810 */
811 struct ethhdr *ehdr;
812 skb_reset_mac_header(skb);
813 ehdr = eth_hdr(skb);
814 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
815 err = -EMSGSIZE;
816 goto out_unlock;
817 }
818 }
819
820 skb->protocol = proto;
821 skb->dev = dev;
822 skb->priority = sk->sk_priority;
823 skb->mark = sk->sk_mark;
824 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
825 if (err < 0)
826 goto out_unlock;
827
828 dev_queue_xmit(skb);
829 rcu_read_unlock();
830 return len;
831
832out_unlock:
833 rcu_read_unlock();
834out_free:
835 kfree_skb(skb);
836 return err;
837}
838
839static inline unsigned int run_filter(const struct sk_buff *skb,
840 const struct sock *sk,
841 unsigned int res)
842{
843 struct sk_filter *filter;
844
845 rcu_read_lock();
846 filter = rcu_dereference(sk->sk_filter);
847 if (filter != NULL)
848 res = SK_RUN_FILTER(filter, skb);
849 rcu_read_unlock();
850
851 return res;
852}
853
854/*
855 * This function makes lazy skb cloning in hope that most of packets
856 * are discarded by BPF.
857 *
858 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
859 * and skb->cb are mangled. It works because (and until) packets
860 * falling here are owned by current CPU. Output packets are cloned
861 * by dev_queue_xmit_nit(), input packets are processed by net_bh
862 * sequencially, so that if we return skb to original state on exit,
863 * we will not harm anyone.
864 */
865
866static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
867 struct packet_type *pt, struct net_device *orig_dev)
868{
869 struct sock *sk;
870 struct sockaddr_ll *sll;
871 struct packet_sock *po;
872 u8 *skb_head = skb->data;
873 int skb_len = skb->len;
874 unsigned int snaplen, res;
875
876 if (skb->pkt_type == PACKET_LOOPBACK)
877 goto drop;
878
879 sk = pt->af_packet_priv;
880 po = pkt_sk(sk);
881
882 if (!net_eq(dev_net(dev), sock_net(sk)))
883 goto drop;
884
885 skb->dev = dev;
886
887 if (dev->header_ops) {
888 /* The device has an explicit notion of ll header,
889 * exported to higher levels.
890 *
891 * Otherwise, the device hides details of its frame
892 * structure, so that corresponding packet head is
893 * never delivered to user.
894 */
895 if (sk->sk_type != SOCK_DGRAM)
896 skb_push(skb, skb->data - skb_mac_header(skb));
897 else if (skb->pkt_type == PACKET_OUTGOING) {
898 /* Special case: outgoing packets have ll header at head */
899 skb_pull(skb, skb_network_offset(skb));
900 }
901 }
902
903 snaplen = skb->len;
904
905 res = run_filter(skb, sk, snaplen);
906 if (!res)
907 goto drop_n_restore;
908 if (snaplen > res)
909 snaplen = res;
910
911 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
912 (unsigned)sk->sk_rcvbuf)
913 goto drop_n_acct;
914
915 if (skb_shared(skb)) {
916 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
917 if (nskb == NULL)
918 goto drop_n_acct;
919
920 if (skb_head != skb->data) {
921 skb->data = skb_head;
922 skb->len = skb_len;
923 }
924 kfree_skb(skb);
925 skb = nskb;
926 }
927
928 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
929 sizeof(skb->cb));
930
931 sll = &PACKET_SKB_CB(skb)->sa.ll;
932 sll->sll_family = AF_PACKET;
933 sll->sll_hatype = dev->type;
934 sll->sll_protocol = skb->protocol;
935 sll->sll_pkttype = skb->pkt_type;
936 if (unlikely(po->origdev))
937 sll->sll_ifindex = orig_dev->ifindex;
938 else
939 sll->sll_ifindex = dev->ifindex;
940
941 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
942
943 PACKET_SKB_CB(skb)->origlen = skb->len;
944
945 if (pskb_trim(skb, snaplen))
946 goto drop_n_acct;
947
948 skb_set_owner_r(skb, sk);
949 skb->dev = NULL;
950 skb_dst_drop(skb);
951
952 /* drop conntrack reference */
953 nf_reset(skb);
954
955 spin_lock(&sk->sk_receive_queue.lock);
956 po->stats.tp_packets++;
957 skb->dropcount = atomic_read(&sk->sk_drops);
958 __skb_queue_tail(&sk->sk_receive_queue, skb);
959 spin_unlock(&sk->sk_receive_queue.lock);
960 sk->sk_data_ready(sk, skb->len);
961 return 0;
962
963drop_n_acct:
964 spin_lock(&sk->sk_receive_queue.lock);
965 po->stats.tp_drops++;
966 atomic_inc(&sk->sk_drops);
967 spin_unlock(&sk->sk_receive_queue.lock);
968
969drop_n_restore:
970 if (skb_head != skb->data && skb_shared(skb)) {
971 skb->data = skb_head;
972 skb->len = skb_len;
973 }
974drop:
975 consume_skb(skb);
976 return 0;
977}
978
979static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
980 struct packet_type *pt, struct net_device *orig_dev)
981{
982 struct sock *sk;
983 struct packet_sock *po;
984 struct sockaddr_ll *sll;
985 union {
986 struct tpacket_hdr *h1;
987 struct tpacket2_hdr *h2;
988 void *raw;
989 } h;
990 u8 *skb_head = skb->data;
991 int skb_len = skb->len;
992 unsigned int snaplen, res;
993 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
994 unsigned short macoff, netoff, hdrlen;
995 struct sk_buff *copy_skb = NULL;
996 struct timeval tv;
997 struct timespec ts;
998 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
999
1000 if (skb->pkt_type == PACKET_LOOPBACK)
1001 goto drop;
1002
1003 sk = pt->af_packet_priv;
1004 po = pkt_sk(sk);
1005
1006 if (!net_eq(dev_net(dev), sock_net(sk)))
1007 goto drop;
1008
1009 if (dev->header_ops) {
1010 if (sk->sk_type != SOCK_DGRAM)
1011 skb_push(skb, skb->data - skb_mac_header(skb));
1012 else if (skb->pkt_type == PACKET_OUTGOING) {
1013 /* Special case: outgoing packets have ll header at head */
1014 skb_pull(skb, skb_network_offset(skb));
1015 }
1016 }
1017
1018 if (skb->ip_summed == CHECKSUM_PARTIAL)
1019 status |= TP_STATUS_CSUMNOTREADY;
1020
1021 snaplen = skb->len;
1022
1023 res = run_filter(skb, sk, snaplen);
1024 if (!res)
1025 goto drop_n_restore;
1026 if (snaplen > res)
1027 snaplen = res;
1028
1029 if (sk->sk_type == SOCK_DGRAM) {
1030 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1031 po->tp_reserve;
1032 } else {
1033 unsigned maclen = skb_network_offset(skb);
1034 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1035 (maclen < 16 ? 16 : maclen)) +
1036 po->tp_reserve;
1037 macoff = netoff - maclen;
1038 }
1039
1040 if (macoff + snaplen > po->rx_ring.frame_size) {
1041 if (po->copy_thresh &&
1042 atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
1043 (unsigned)sk->sk_rcvbuf) {
1044 if (skb_shared(skb)) {
1045 copy_skb = skb_clone(skb, GFP_ATOMIC);
1046 } else {
1047 copy_skb = skb_get(skb);
1048 skb_head = skb->data;
1049 }
1050 if (copy_skb)
1051 skb_set_owner_r(copy_skb, sk);
1052 }
1053 snaplen = po->rx_ring.frame_size - macoff;
1054 if ((int)snaplen < 0)
1055 snaplen = 0;
1056 }
1057
1058 spin_lock(&sk->sk_receive_queue.lock);
1059 h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
1060 if (!h.raw)
1061 goto ring_is_full;
1062 packet_increment_head(&po->rx_ring);
1063 po->stats.tp_packets++;
1064 if (copy_skb) {
1065 status |= TP_STATUS_COPY;
1066 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1067 }
1068 if (!po->stats.tp_drops)
1069 status &= ~TP_STATUS_LOSING;
1070 spin_unlock(&sk->sk_receive_queue.lock);
1071
1072 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1073
1074 switch (po->tp_version) {
1075 case TPACKET_V1:
1076 h.h1->tp_len = skb->len;
1077 h.h1->tp_snaplen = snaplen;
1078 h.h1->tp_mac = macoff;
1079 h.h1->tp_net = netoff;
1080 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1081 && shhwtstamps->syststamp.tv64)
1082 tv = ktime_to_timeval(shhwtstamps->syststamp);
1083 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1084 && shhwtstamps->hwtstamp.tv64)
1085 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1086 else if (skb->tstamp.tv64)
1087 tv = ktime_to_timeval(skb->tstamp);
1088 else
1089 do_gettimeofday(&tv);
1090 h.h1->tp_sec = tv.tv_sec;
1091 h.h1->tp_usec = tv.tv_usec;
1092 hdrlen = sizeof(*h.h1);
1093 break;
1094 case TPACKET_V2:
1095 h.h2->tp_len = skb->len;
1096 h.h2->tp_snaplen = snaplen;
1097 h.h2->tp_mac = macoff;
1098 h.h2->tp_net = netoff;
1099 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1100 && shhwtstamps->syststamp.tv64)
1101 ts = ktime_to_timespec(shhwtstamps->syststamp);
1102 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1103 && shhwtstamps->hwtstamp.tv64)
1104 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1105 else if (skb->tstamp.tv64)
1106 ts = ktime_to_timespec(skb->tstamp);
1107 else
1108 getnstimeofday(&ts);
1109 h.h2->tp_sec = ts.tv_sec;
1110 h.h2->tp_nsec = ts.tv_nsec;
1111 if (vlan_tx_tag_present(skb)) {
1112 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1113 status |= TP_STATUS_VLAN_VALID;
1114 } else {
1115 h.h2->tp_vlan_tci = 0;
1116 }
1117 h.h2->tp_padding = 0;
1118 hdrlen = sizeof(*h.h2);
1119 break;
1120 default:
1121 BUG();
1122 }
1123
1124 sll = h.raw + TPACKET_ALIGN(hdrlen);
1125 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1126 sll->sll_family = AF_PACKET;
1127 sll->sll_hatype = dev->type;
1128 sll->sll_protocol = skb->protocol;
1129 sll->sll_pkttype = skb->pkt_type;
1130 if (unlikely(po->origdev))
1131 sll->sll_ifindex = orig_dev->ifindex;
1132 else
1133 sll->sll_ifindex = dev->ifindex;
1134
1135 smp_mb();
1136#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1137 {
1138 u8 *start, *end;
1139
1140 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen);
1141 for (start = h.raw; start < end; start += PAGE_SIZE)
1142 flush_dcache_page(pgv_to_page(start));
1143 smp_wmb();
1144 }
1145#endif
1146 __packet_set_status(po, h.raw, status);
1147
1148 sk->sk_data_ready(sk, 0);
1149
1150drop_n_restore:
1151 if (skb_head != skb->data && skb_shared(skb)) {
1152 skb->data = skb_head;
1153 skb->len = skb_len;
1154 }
1155drop:
1156 kfree_skb(skb);
1157 return 0;
1158
1159ring_is_full:
1160 po->stats.tp_drops++;
1161 spin_unlock(&sk->sk_receive_queue.lock);
1162
1163 sk->sk_data_ready(sk, 0);
1164 kfree_skb(copy_skb);
1165 goto drop_n_restore;
1166}
1167
1168static void tpacket_destruct_skb(struct sk_buff *skb)
1169{
1170 struct packet_sock *po = pkt_sk(skb->sk);
1171 void *ph;
1172
1173 BUG_ON(skb == NULL);
1174
1175 if (likely(po->tx_ring.pg_vec)) {
1176 ph = skb_shinfo(skb)->destructor_arg;
1177 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
1178 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1179 atomic_dec(&po->tx_ring.pending);
1180 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1181 }
1182
1183 sock_wfree(skb);
1184}
1185
1186static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1187 void *frame, struct net_device *dev, int size_max,
1188 __be16 proto, unsigned char *addr)
1189{
1190 union {
1191 struct tpacket_hdr *h1;
1192 struct tpacket2_hdr *h2;
1193 void *raw;
1194 } ph;
1195 int to_write, offset, len, tp_len, nr_frags, len_max;
1196 struct socket *sock = po->sk.sk_socket;
1197 struct page *page;
1198 void *data;
1199 int err;
1200
1201 ph.raw = frame;
1202
1203 skb->protocol = proto;
1204 skb->dev = dev;
1205 skb->priority = po->sk.sk_priority;
1206 skb->mark = po->sk.sk_mark;
1207 skb_shinfo(skb)->destructor_arg = ph.raw;
1208
1209 switch (po->tp_version) {
1210 case TPACKET_V2:
1211 tp_len = ph.h2->tp_len;
1212 break;
1213 default:
1214 tp_len = ph.h1->tp_len;
1215 break;
1216 }
1217 if (unlikely(tp_len > size_max)) {
1218 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1219 return -EMSGSIZE;
1220 }
1221
1222 skb_reserve(skb, LL_RESERVED_SPACE(dev));
1223 skb_reset_network_header(skb);
1224
1225 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1226 to_write = tp_len;
1227
1228 if (sock->type == SOCK_DGRAM) {
1229 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1230 NULL, tp_len);
1231 if (unlikely(err < 0))
1232 return -EINVAL;
1233 } else if (dev->hard_header_len) {
1234 /* net device doesn't like empty head */
1235 if (unlikely(tp_len <= dev->hard_header_len)) {
1236 pr_err("packet size is too short (%d < %d)\n",
1237 tp_len, dev->hard_header_len);
1238 return -EINVAL;
1239 }
1240
1241 skb_push(skb, dev->hard_header_len);
1242 err = skb_store_bits(skb, 0, data,
1243 dev->hard_header_len);
1244 if (unlikely(err))
1245 return err;
1246
1247 data += dev->hard_header_len;
1248 to_write -= dev->hard_header_len;
1249 }
1250
1251 err = -EFAULT;
1252 offset = offset_in_page(data);
1253 len_max = PAGE_SIZE - offset;
1254 len = ((to_write > len_max) ? len_max : to_write);
1255
1256 skb->data_len = to_write;
1257 skb->len += to_write;
1258 skb->truesize += to_write;
1259 atomic_add(to_write, &po->sk.sk_wmem_alloc);
1260
1261 while (likely(to_write)) {
1262 nr_frags = skb_shinfo(skb)->nr_frags;
1263
1264 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
1265 pr_err("Packet exceed the number of skb frags(%lu)\n",
1266 MAX_SKB_FRAGS);
1267 return -EFAULT;
1268 }
1269
1270 page = pgv_to_page(data);
1271 data += len;
1272 flush_dcache_page(page);
1273 get_page(page);
1274 skb_fill_page_desc(skb, nr_frags, page, offset, len);
1275 to_write -= len;
1276 offset = 0;
1277 len_max = PAGE_SIZE;
1278 len = ((to_write > len_max) ? len_max : to_write);
1279 }
1280
1281 return tp_len;
1282}
1283
1284static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
1285{
1286 struct sk_buff *skb;
1287 struct net_device *dev;
1288 __be16 proto;
1289 bool need_rls_dev = false;
1290 int err, reserve = 0;
1291 void *ph;
1292 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
1293 int tp_len, size_max;
1294 unsigned char *addr;
1295 int len_sum = 0;
1296 int status = 0;
1297
1298 mutex_lock(&po->pg_vec_lock);
1299
1300 err = -EBUSY;
1301 if (saddr == NULL) {
1302 dev = po->prot_hook.dev;
1303 proto = po->num;
1304 addr = NULL;
1305 } else {
1306 err = -EINVAL;
1307 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
1308 goto out;
1309 if (msg->msg_namelen < (saddr->sll_halen
1310 + offsetof(struct sockaddr_ll,
1311 sll_addr)))
1312 goto out;
1313 proto = saddr->sll_protocol;
1314 addr = saddr->sll_addr;
1315 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
1316 need_rls_dev = true;
1317 }
1318
1319 err = -ENXIO;
1320 if (unlikely(dev == NULL))
1321 goto out;
1322
1323 reserve = dev->hard_header_len;
1324
1325 err = -ENETDOWN;
1326 if (unlikely(!(dev->flags & IFF_UP)))
1327 goto out_put;
1328
1329 size_max = po->tx_ring.frame_size
1330 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
1331
1332 if (size_max > dev->mtu + reserve)
1333 size_max = dev->mtu + reserve;
1334
1335 do {
1336 ph = packet_current_frame(po, &po->tx_ring,
1337 TP_STATUS_SEND_REQUEST);
1338
1339 if (unlikely(ph == NULL)) {
1340 schedule();
1341 continue;
1342 }
1343
1344 status = TP_STATUS_SEND_REQUEST;
1345 skb = sock_alloc_send_skb(&po->sk,
1346 LL_ALLOCATED_SPACE(dev)
1347 + sizeof(struct sockaddr_ll),
1348 0, &err);
1349
1350 if (unlikely(skb == NULL))
1351 goto out_status;
1352
1353 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
1354 addr);
1355
1356 if (unlikely(tp_len < 0)) {
1357 if (po->tp_loss) {
1358 __packet_set_status(po, ph,
1359 TP_STATUS_AVAILABLE);
1360 packet_increment_head(&po->tx_ring);
1361 kfree_skb(skb);
1362 continue;
1363 } else {
1364 status = TP_STATUS_WRONG_FORMAT;
1365 err = tp_len;
1366 goto out_status;
1367 }
1368 }
1369
1370 skb->destructor = tpacket_destruct_skb;
1371 __packet_set_status(po, ph, TP_STATUS_SENDING);
1372 atomic_inc(&po->tx_ring.pending);
1373
1374 status = TP_STATUS_SEND_REQUEST;
1375 err = dev_queue_xmit(skb);
1376 if (unlikely(err > 0)) {
1377 err = net_xmit_errno(err);
1378 if (err && __packet_get_status(po, ph) ==
1379 TP_STATUS_AVAILABLE) {
1380 /* skb was destructed already */
1381 skb = NULL;
1382 goto out_status;
1383 }
1384 /*
1385 * skb was dropped but not destructed yet;
1386 * let's treat it like congestion or err < 0
1387 */
1388 err = 0;
1389 }
1390 packet_increment_head(&po->tx_ring);
1391 len_sum += tp_len;
1392 } while (likely((ph != NULL) ||
1393 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
1394 (atomic_read(&po->tx_ring.pending))))
1395 );
1396
1397 err = len_sum;
1398 goto out_put;
1399
1400out_status:
1401 __packet_set_status(po, ph, status);
1402 kfree_skb(skb);
1403out_put:
1404 if (need_rls_dev)
1405 dev_put(dev);
1406out:
1407 mutex_unlock(&po->pg_vec_lock);
1408 return err;
1409}
1410
1411static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
1412 size_t reserve, size_t len,
1413 size_t linear, int noblock,
1414 int *err)
1415{
1416 struct sk_buff *skb;
1417
1418 /* Under a page? Don't bother with paged skb. */
1419 if (prepad + len < PAGE_SIZE || !linear)
1420 linear = len;
1421
1422 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
1423 err);
1424 if (!skb)
1425 return NULL;
1426
1427 skb_reserve(skb, reserve);
1428 skb_put(skb, linear);
1429 skb->data_len = len - linear;
1430 skb->len += len - linear;
1431
1432 return skb;
1433}
1434
1435static int packet_snd(struct socket *sock,
1436 struct msghdr *msg, size_t len)
1437{
1438 struct sock *sk = sock->sk;
1439 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
1440 struct sk_buff *skb;
1441 struct net_device *dev;
1442 __be16 proto;
1443 bool need_rls_dev = false;
1444 unsigned char *addr;
1445 int err, reserve = 0;
1446 struct virtio_net_hdr vnet_hdr = { 0 };
1447 int offset = 0;
1448 int vnet_hdr_len;
1449 struct packet_sock *po = pkt_sk(sk);
1450 unsigned short gso_type = 0;
1451
1452 /*
1453 * Get and verify the address.
1454 */
1455
1456 if (saddr == NULL) {
1457 dev = po->prot_hook.dev;
1458 proto = po->num;
1459 addr = NULL;
1460 } else {
1461 err = -EINVAL;
1462 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
1463 goto out;
1464 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
1465 goto out;
1466 proto = saddr->sll_protocol;
1467 addr = saddr->sll_addr;
1468 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
1469 need_rls_dev = true;
1470 }
1471
1472 err = -ENXIO;
1473 if (dev == NULL)
1474 goto out_unlock;
1475 if (sock->type == SOCK_RAW)
1476 reserve = dev->hard_header_len;
1477
1478 err = -ENETDOWN;
1479 if (!(dev->flags & IFF_UP))
1480 goto out_unlock;
1481
1482 if (po->has_vnet_hdr) {
1483 vnet_hdr_len = sizeof(vnet_hdr);
1484
1485 err = -EINVAL;
1486 if (len < vnet_hdr_len)
1487 goto out_unlock;
1488
1489 len -= vnet_hdr_len;
1490
1491 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
1492 vnet_hdr_len);
1493 if (err < 0)
1494 goto out_unlock;
1495
1496 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
1497 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
1498 vnet_hdr.hdr_len))
1499 vnet_hdr.hdr_len = vnet_hdr.csum_start +
1500 vnet_hdr.csum_offset + 2;
1501
1502 err = -EINVAL;
1503 if (vnet_hdr.hdr_len > len)
1504 goto out_unlock;
1505
1506 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
1507 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
1508 case VIRTIO_NET_HDR_GSO_TCPV4:
1509 gso_type = SKB_GSO_TCPV4;
1510 break;
1511 case VIRTIO_NET_HDR_GSO_TCPV6:
1512 gso_type = SKB_GSO_TCPV6;
1513 break;
1514 case VIRTIO_NET_HDR_GSO_UDP:
1515 gso_type = SKB_GSO_UDP;
1516 break;
1517 default:
1518 goto out_unlock;
1519 }
1520
1521 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
1522 gso_type |= SKB_GSO_TCP_ECN;
1523
1524 if (vnet_hdr.gso_size == 0)
1525 goto out_unlock;
1526
1527 }
1528 }
1529
1530 err = -EMSGSIZE;
1531 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
1532 goto out_unlock;
1533
1534 err = -ENOBUFS;
1535 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
1536 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
1537 msg->msg_flags & MSG_DONTWAIT, &err);
1538 if (skb == NULL)
1539 goto out_unlock;
1540
1541 skb_set_network_header(skb, reserve);
1542
1543 err = -EINVAL;
1544 if (sock->type == SOCK_DGRAM &&
1545 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1546 goto out_free;
1547
1548 /* Returns -EFAULT on error */
1549 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
1550 if (err)
1551 goto out_free;
1552 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1553 if (err < 0)
1554 goto out_free;
1555
1556 if (!gso_type && (len > dev->mtu + reserve)) {
1557 /* Earlier code assumed this would be a VLAN pkt,
1558 * double-check this now that we have the actual
1559 * packet in hand.
1560 */
1561 struct ethhdr *ehdr;
1562 skb_reset_mac_header(skb);
1563 ehdr = eth_hdr(skb);
1564 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1565 err = -EMSGSIZE;
1566 goto out_free;
1567 }
1568 }
1569
1570 skb->protocol = proto;
1571 skb->dev = dev;
1572 skb->priority = sk->sk_priority;
1573 skb->mark = sk->sk_mark;
1574
1575 if (po->has_vnet_hdr) {
1576 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1577 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
1578 vnet_hdr.csum_offset)) {
1579 err = -EINVAL;
1580 goto out_free;
1581 }
1582 }
1583
1584 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
1585 skb_shinfo(skb)->gso_type = gso_type;
1586
1587 /* Header must be checked, and gso_segs computed. */
1588 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
1589 skb_shinfo(skb)->gso_segs = 0;
1590
1591 len += vnet_hdr_len;
1592 }
1593
1594 /*
1595 * Now send it
1596 */
1597
1598 err = dev_queue_xmit(skb);
1599 if (err > 0 && (err = net_xmit_errno(err)) != 0)
1600 goto out_unlock;
1601
1602 if (need_rls_dev)
1603 dev_put(dev);
1604
1605 return len;
1606
1607out_free:
1608 kfree_skb(skb);
1609out_unlock:
1610 if (dev && need_rls_dev)
1611 dev_put(dev);
1612out:
1613 return err;
1614}
1615
1616static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
1617 struct msghdr *msg, size_t len)
1618{
1619 struct sock *sk = sock->sk;
1620 struct packet_sock *po = pkt_sk(sk);
1621 if (po->tx_ring.pg_vec)
1622 return tpacket_snd(po, msg);
1623 else
1624 return packet_snd(sock, msg, len);
1625}
1626
1627/*
1628 * Close a PACKET socket. This is fairly simple. We immediately go
1629 * to 'closed' state and remove our protocol entry in the device list.
1630 */
1631
1632static int packet_release(struct socket *sock)
1633{
1634 struct sock *sk = sock->sk;
1635 struct packet_sock *po;
1636 struct net *net;
1637 struct tpacket_req req;
1638
1639 if (!sk)
1640 return 0;
1641
1642 net = sock_net(sk);
1643 po = pkt_sk(sk);
1644
1645 spin_lock_bh(&net->packet.sklist_lock);
1646 sk_del_node_init_rcu(sk);
1647 sock_prot_inuse_add(net, sk->sk_prot, -1);
1648 spin_unlock_bh(&net->packet.sklist_lock);
1649
1650 spin_lock(&po->bind_lock);
1651 unregister_prot_hook(sk, false);
1652 if (po->prot_hook.dev) {
1653 dev_put(po->prot_hook.dev);
1654 po->prot_hook.dev = NULL;
1655 }
1656 spin_unlock(&po->bind_lock);
1657
1658 packet_flush_mclist(sk);
1659
1660 memset(&req, 0, sizeof(req));
1661
1662 if (po->rx_ring.pg_vec)
1663 packet_set_ring(sk, &req, 1, 0);
1664
1665 if (po->tx_ring.pg_vec)
1666 packet_set_ring(sk, &req, 1, 1);
1667
1668 fanout_release(sk);
1669
1670 synchronize_net();
1671 /*
1672 * Now the socket is dead. No more input will appear.
1673 */
1674 sock_orphan(sk);
1675 sock->sk = NULL;
1676
1677 /* Purge queues */
1678
1679 skb_queue_purge(&sk->sk_receive_queue);
1680 sk_refcnt_debug_release(sk);
1681
1682 sock_put(sk);
1683 return 0;
1684}
1685
1686/*
1687 * Attach a packet hook.
1688 */
1689
1690static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
1691{
1692 struct packet_sock *po = pkt_sk(sk);
1693
1694 if (po->fanout)
1695 return -EINVAL;
1696
1697 lock_sock(sk);
1698
1699 spin_lock(&po->bind_lock);
1700 unregister_prot_hook(sk, true);
1701 po->num = protocol;
1702 po->prot_hook.type = protocol;
1703 if (po->prot_hook.dev)
1704 dev_put(po->prot_hook.dev);
1705 po->prot_hook.dev = dev;
1706
1707 po->ifindex = dev ? dev->ifindex : 0;
1708
1709 if (protocol == 0)
1710 goto out_unlock;
1711
1712 if (!dev || (dev->flags & IFF_UP)) {
1713 register_prot_hook(sk);
1714 } else {
1715 sk->sk_err = ENETDOWN;
1716 if (!sock_flag(sk, SOCK_DEAD))
1717 sk->sk_error_report(sk);
1718 }
1719
1720out_unlock:
1721 spin_unlock(&po->bind_lock);
1722 release_sock(sk);
1723 return 0;
1724}
1725
1726/*
1727 * Bind a packet socket to a device
1728 */
1729
1730static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
1731 int addr_len)
1732{
1733 struct sock *sk = sock->sk;
1734 char name[15];
1735 struct net_device *dev;
1736 int err = -ENODEV;
1737
1738 /*
1739 * Check legality
1740 */
1741
1742 if (addr_len != sizeof(struct sockaddr))
1743 return -EINVAL;
1744 strlcpy(name, uaddr->sa_data, sizeof(name));
1745
1746 dev = dev_get_by_name(sock_net(sk), name);
1747 if (dev)
1748 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
1749 return err;
1750}
1751
1752static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1753{
1754 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
1755 struct sock *sk = sock->sk;
1756 struct net_device *dev = NULL;
1757 int err;
1758
1759
1760 /*
1761 * Check legality
1762 */
1763
1764 if (addr_len < sizeof(struct sockaddr_ll))
1765 return -EINVAL;
1766 if (sll->sll_family != AF_PACKET)
1767 return -EINVAL;
1768
1769 if (sll->sll_ifindex) {
1770 err = -ENODEV;
1771 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1772 if (dev == NULL)
1773 goto out;
1774 }
1775 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1776
1777out:
1778 return err;
1779}
1780
1781static struct proto packet_proto = {
1782 .name = "PACKET",
1783 .owner = THIS_MODULE,
1784 .obj_size = sizeof(struct packet_sock),
1785};
1786
1787/*
1788 * Create a packet of type SOCK_PACKET.
1789 */
1790
1791static int packet_create(struct net *net, struct socket *sock, int protocol,
1792 int kern)
1793{
1794 struct sock *sk;
1795 struct packet_sock *po;
1796 __be16 proto = (__force __be16)protocol; /* weird, but documented */
1797 int err;
1798
1799 if (!capable(CAP_NET_RAW))
1800 return -EPERM;
1801 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1802 sock->type != SOCK_PACKET)
1803 return -ESOCKTNOSUPPORT;
1804
1805 sock->state = SS_UNCONNECTED;
1806
1807 err = -ENOBUFS;
1808 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1809 if (sk == NULL)
1810 goto out;
1811
1812 sock->ops = &packet_ops;
1813 if (sock->type == SOCK_PACKET)
1814 sock->ops = &packet_ops_spkt;
1815
1816 sock_init_data(sock, sk);
1817
1818 po = pkt_sk(sk);
1819 sk->sk_family = PF_PACKET;
1820 po->num = proto;
1821
1822 sk->sk_destruct = packet_sock_destruct;
1823 sk_refcnt_debug_inc(sk);
1824
1825 /*
1826 * Attach a protocol block
1827 */
1828
1829 spin_lock_init(&po->bind_lock);
1830 mutex_init(&po->pg_vec_lock);
1831 po->prot_hook.func = packet_rcv;
1832
1833 if (sock->type == SOCK_PACKET)
1834 po->prot_hook.func = packet_rcv_spkt;
1835
1836 po->prot_hook.af_packet_priv = sk;
1837
1838 if (proto) {
1839 po->prot_hook.type = proto;
1840 register_prot_hook(sk);
1841 }
1842
1843 spin_lock_bh(&net->packet.sklist_lock);
1844 sk_add_node_rcu(sk, &net->packet.sklist);
1845 sock_prot_inuse_add(net, &packet_proto, 1);
1846 spin_unlock_bh(&net->packet.sklist_lock);
1847
1848 return 0;
1849out:
1850 return err;
1851}
1852
1853static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
1854{
1855 struct sock_exterr_skb *serr;
1856 struct sk_buff *skb, *skb2;
1857 int copied, err;
1858
1859 err = -EAGAIN;
1860 skb = skb_dequeue(&sk->sk_error_queue);
1861 if (skb == NULL)
1862 goto out;
1863
1864 copied = skb->len;
1865 if (copied > len) {
1866 msg->msg_flags |= MSG_TRUNC;
1867 copied = len;
1868 }
1869 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1870 if (err)
1871 goto out_free_skb;
1872
1873 sock_recv_timestamp(msg, sk, skb);
1874
1875 serr = SKB_EXT_ERR(skb);
1876 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
1877 sizeof(serr->ee), &serr->ee);
1878
1879 msg->msg_flags |= MSG_ERRQUEUE;
1880 err = copied;
1881
1882 /* Reset and regenerate socket error */
1883 spin_lock_bh(&sk->sk_error_queue.lock);
1884 sk->sk_err = 0;
1885 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
1886 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
1887 spin_unlock_bh(&sk->sk_error_queue.lock);
1888 sk->sk_error_report(sk);
1889 } else
1890 spin_unlock_bh(&sk->sk_error_queue.lock);
1891
1892out_free_skb:
1893 kfree_skb(skb);
1894out:
1895 return err;
1896}
1897
1898/*
1899 * Pull a packet from our receive queue and hand it to the user.
1900 * If necessary we block.
1901 */
1902
1903static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1904 struct msghdr *msg, size_t len, int flags)
1905{
1906 struct sock *sk = sock->sk;
1907 struct sk_buff *skb;
1908 int copied, err;
1909 struct sockaddr_ll *sll;
1910 int vnet_hdr_len = 0;
1911
1912 err = -EINVAL;
1913 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
1914 goto out;
1915
1916#if 0
1917 /* What error should we return now? EUNATTACH? */
1918 if (pkt_sk(sk)->ifindex < 0)
1919 return -ENODEV;
1920#endif
1921
1922 if (flags & MSG_ERRQUEUE) {
1923 err = packet_recv_error(sk, msg, len);
1924 goto out;
1925 }
1926
1927 /*
1928 * Call the generic datagram receiver. This handles all sorts
1929 * of horrible races and re-entrancy so we can forget about it
1930 * in the protocol layers.
1931 *
1932 * Now it will return ENETDOWN, if device have just gone down,
1933 * but then it will block.
1934 */
1935
1936 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
1937
1938 /*
1939 * An error occurred so return it. Because skb_recv_datagram()
1940 * handles the blocking we don't see and worry about blocking
1941 * retries.
1942 */
1943
1944 if (skb == NULL)
1945 goto out;
1946
1947 if (pkt_sk(sk)->has_vnet_hdr) {
1948 struct virtio_net_hdr vnet_hdr = { 0 };
1949
1950 err = -EINVAL;
1951 vnet_hdr_len = sizeof(vnet_hdr);
1952 if (len < vnet_hdr_len)
1953 goto out_free;
1954
1955 len -= vnet_hdr_len;
1956
1957 if (skb_is_gso(skb)) {
1958 struct skb_shared_info *sinfo = skb_shinfo(skb);
1959
1960 /* This is a hint as to how much should be linear. */
1961 vnet_hdr.hdr_len = skb_headlen(skb);
1962 vnet_hdr.gso_size = sinfo->gso_size;
1963 if (sinfo->gso_type & SKB_GSO_TCPV4)
1964 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1965 else if (sinfo->gso_type & SKB_GSO_TCPV6)
1966 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1967 else if (sinfo->gso_type & SKB_GSO_UDP)
1968 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
1969 else if (sinfo->gso_type & SKB_GSO_FCOE)
1970 goto out_free;
1971 else
1972 BUG();
1973 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1974 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1975 } else
1976 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
1977
1978 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1979 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1980 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
1981 vnet_hdr.csum_offset = skb->csum_offset;
1982 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
1983 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
1984 } /* else everything is zero */
1985
1986 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
1987 vnet_hdr_len);
1988 if (err < 0)
1989 goto out_free;
1990 }
1991
1992 /*
1993 * If the address length field is there to be filled in, we fill
1994 * it in now.
1995 */
1996
1997 sll = &PACKET_SKB_CB(skb)->sa.ll;
1998 if (sock->type == SOCK_PACKET)
1999 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2000 else
2001 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2002
2003 /*
2004 * You lose any data beyond the buffer you gave. If it worries a
2005 * user program they can ask the device for its MTU anyway.
2006 */
2007
2008 copied = skb->len;
2009 if (copied > len) {
2010 copied = len;
2011 msg->msg_flags |= MSG_TRUNC;
2012 }
2013
2014 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2015 if (err)
2016 goto out_free;
2017
2018 sock_recv_ts_and_drops(msg, sk, skb);
2019
2020 if (msg->msg_name)
2021 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2022 msg->msg_namelen);
2023
2024 if (pkt_sk(sk)->auxdata) {
2025 struct tpacket_auxdata aux;
2026
2027 aux.tp_status = TP_STATUS_USER;
2028 if (skb->ip_summed == CHECKSUM_PARTIAL)
2029 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2030 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2031 aux.tp_snaplen = skb->len;
2032 aux.tp_mac = 0;
2033 aux.tp_net = skb_network_offset(skb);
2034 if (vlan_tx_tag_present(skb)) {
2035 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2036 aux.tp_status |= TP_STATUS_VLAN_VALID;
2037 } else {
2038 aux.tp_vlan_tci = 0;
2039 }
2040 aux.tp_padding = 0;
2041 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2042 }
2043
2044 /*
2045 * Free or return the buffer as appropriate. Again this
2046 * hides all the races and re-entrancy issues from us.
2047 */
2048 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2049
2050out_free:
2051 skb_free_datagram(sk, skb);
2052out:
2053 return err;
2054}
2055
2056static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2057 int *uaddr_len, int peer)
2058{
2059 struct net_device *dev;
2060 struct sock *sk = sock->sk;
2061
2062 if (peer)
2063 return -EOPNOTSUPP;
2064
2065 uaddr->sa_family = AF_PACKET;
2066 rcu_read_lock();
2067 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2068 if (dev)
2069 strncpy(uaddr->sa_data, dev->name, 14);
2070 else
2071 memset(uaddr->sa_data, 0, 14);
2072 rcu_read_unlock();
2073 *uaddr_len = sizeof(*uaddr);
2074
2075 return 0;
2076}
2077
2078static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2079 int *uaddr_len, int peer)
2080{
2081 struct net_device *dev;
2082 struct sock *sk = sock->sk;
2083 struct packet_sock *po = pkt_sk(sk);
2084 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2085
2086 if (peer)
2087 return -EOPNOTSUPP;
2088
2089 sll->sll_family = AF_PACKET;
2090 sll->sll_ifindex = po->ifindex;
2091 sll->sll_protocol = po->num;
2092 sll->sll_pkttype = 0;
2093 rcu_read_lock();
2094 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2095 if (dev) {
2096 sll->sll_hatype = dev->type;
2097 sll->sll_halen = dev->addr_len;
2098 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2099 } else {
2100 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2101 sll->sll_halen = 0;
2102 }
2103 rcu_read_unlock();
2104 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2105
2106 return 0;
2107}
2108
2109static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2110 int what)
2111{
2112 switch (i->type) {
2113 case PACKET_MR_MULTICAST:
2114 if (i->alen != dev->addr_len)
2115 return -EINVAL;
2116 if (what > 0)
2117 return dev_mc_add(dev, i->addr);
2118 else
2119 return dev_mc_del(dev, i->addr);
2120 break;
2121 case PACKET_MR_PROMISC:
2122 return dev_set_promiscuity(dev, what);
2123 break;
2124 case PACKET_MR_ALLMULTI:
2125 return dev_set_allmulti(dev, what);
2126 break;
2127 case PACKET_MR_UNICAST:
2128 if (i->alen != dev->addr_len)
2129 return -EINVAL;
2130 if (what > 0)
2131 return dev_uc_add(dev, i->addr);
2132 else
2133 return dev_uc_del(dev, i->addr);
2134 break;
2135 default:
2136 break;
2137 }
2138 return 0;
2139}
2140
2141static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2142{
2143 for ( ; i; i = i->next) {
2144 if (i->ifindex == dev->ifindex)
2145 packet_dev_mc(dev, i, what);
2146 }
2147}
2148
2149static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2150{
2151 struct packet_sock *po = pkt_sk(sk);
2152 struct packet_mclist *ml, *i;
2153 struct net_device *dev;
2154 int err;
2155
2156 rtnl_lock();
2157
2158 err = -ENODEV;
2159 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2160 if (!dev)
2161 goto done;
2162
2163 err = -EINVAL;
2164 if (mreq->mr_alen > dev->addr_len)
2165 goto done;
2166
2167 err = -ENOBUFS;
2168 i = kmalloc(sizeof(*i), GFP_KERNEL);
2169 if (i == NULL)
2170 goto done;
2171
2172 err = 0;
2173 for (ml = po->mclist; ml; ml = ml->next) {
2174 if (ml->ifindex == mreq->mr_ifindex &&
2175 ml->type == mreq->mr_type &&
2176 ml->alen == mreq->mr_alen &&
2177 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2178 ml->count++;
2179 /* Free the new element ... */
2180 kfree(i);
2181 goto done;
2182 }
2183 }
2184
2185 i->type = mreq->mr_type;
2186 i->ifindex = mreq->mr_ifindex;
2187 i->alen = mreq->mr_alen;
2188 memcpy(i->addr, mreq->mr_address, i->alen);
2189 i->count = 1;
2190 i->next = po->mclist;
2191 po->mclist = i;
2192 err = packet_dev_mc(dev, i, 1);
2193 if (err) {
2194 po->mclist = i->next;
2195 kfree(i);
2196 }
2197
2198done:
2199 rtnl_unlock();
2200 return err;
2201}
2202
2203static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2204{
2205 struct packet_mclist *ml, **mlp;
2206
2207 rtnl_lock();
2208
2209 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2210 if (ml->ifindex == mreq->mr_ifindex &&
2211 ml->type == mreq->mr_type &&
2212 ml->alen == mreq->mr_alen &&
2213 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2214 if (--ml->count == 0) {
2215 struct net_device *dev;
2216 *mlp = ml->next;
2217 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2218 if (dev)
2219 packet_dev_mc(dev, ml, -1);
2220 kfree(ml);
2221 }
2222 rtnl_unlock();
2223 return 0;
2224 }
2225 }
2226 rtnl_unlock();
2227 return -EADDRNOTAVAIL;
2228}
2229
2230static void packet_flush_mclist(struct sock *sk)
2231{
2232 struct packet_sock *po = pkt_sk(sk);
2233 struct packet_mclist *ml;
2234
2235 if (!po->mclist)
2236 return;
2237
2238 rtnl_lock();
2239 while ((ml = po->mclist) != NULL) {
2240 struct net_device *dev;
2241
2242 po->mclist = ml->next;
2243 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2244 if (dev != NULL)
2245 packet_dev_mc(dev, ml, -1);
2246 kfree(ml);
2247 }
2248 rtnl_unlock();
2249}
2250
2251static int
2252packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
2253{
2254 struct sock *sk = sock->sk;
2255 struct packet_sock *po = pkt_sk(sk);
2256 int ret;
2257
2258 if (level != SOL_PACKET)
2259 return -ENOPROTOOPT;
2260
2261 switch (optname) {
2262 case PACKET_ADD_MEMBERSHIP:
2263 case PACKET_DROP_MEMBERSHIP:
2264 {
2265 struct packet_mreq_max mreq;
2266 int len = optlen;
2267 memset(&mreq, 0, sizeof(mreq));
2268 if (len < sizeof(struct packet_mreq))
2269 return -EINVAL;
2270 if (len > sizeof(mreq))
2271 len = sizeof(mreq);
2272 if (copy_from_user(&mreq, optval, len))
2273 return -EFAULT;
2274 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
2275 return -EINVAL;
2276 if (optname == PACKET_ADD_MEMBERSHIP)
2277 ret = packet_mc_add(sk, &mreq);
2278 else
2279 ret = packet_mc_drop(sk, &mreq);
2280 return ret;
2281 }
2282
2283 case PACKET_RX_RING:
2284 case PACKET_TX_RING:
2285 {
2286 struct tpacket_req req;
2287
2288 if (optlen < sizeof(req))
2289 return -EINVAL;
2290 if (pkt_sk(sk)->has_vnet_hdr)
2291 return -EINVAL;
2292 if (copy_from_user(&req, optval, sizeof(req)))
2293 return -EFAULT;
2294 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
2295 }
2296 case PACKET_COPY_THRESH:
2297 {
2298 int val;
2299
2300 if (optlen != sizeof(val))
2301 return -EINVAL;
2302 if (copy_from_user(&val, optval, sizeof(val)))
2303 return -EFAULT;
2304
2305 pkt_sk(sk)->copy_thresh = val;
2306 return 0;
2307 }
2308 case PACKET_VERSION:
2309 {
2310 int val;
2311
2312 if (optlen != sizeof(val))
2313 return -EINVAL;
2314 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2315 return -EBUSY;
2316 if (copy_from_user(&val, optval, sizeof(val)))
2317 return -EFAULT;
2318 switch (val) {
2319 case TPACKET_V1:
2320 case TPACKET_V2:
2321 po->tp_version = val;
2322 return 0;
2323 default:
2324 return -EINVAL;
2325 }
2326 }
2327 case PACKET_RESERVE:
2328 {
2329 unsigned int val;
2330
2331 if (optlen != sizeof(val))
2332 return -EINVAL;
2333 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2334 return -EBUSY;
2335 if (copy_from_user(&val, optval, sizeof(val)))
2336 return -EFAULT;
2337 po->tp_reserve = val;
2338 return 0;
2339 }
2340 case PACKET_LOSS:
2341 {
2342 unsigned int val;
2343
2344 if (optlen != sizeof(val))
2345 return -EINVAL;
2346 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2347 return -EBUSY;
2348 if (copy_from_user(&val, optval, sizeof(val)))
2349 return -EFAULT;
2350 po->tp_loss = !!val;
2351 return 0;
2352 }
2353 case PACKET_AUXDATA:
2354 {
2355 int val;
2356
2357 if (optlen < sizeof(val))
2358 return -EINVAL;
2359 if (copy_from_user(&val, optval, sizeof(val)))
2360 return -EFAULT;
2361
2362 po->auxdata = !!val;
2363 return 0;
2364 }
2365 case PACKET_ORIGDEV:
2366 {
2367 int val;
2368
2369 if (optlen < sizeof(val))
2370 return -EINVAL;
2371 if (copy_from_user(&val, optval, sizeof(val)))
2372 return -EFAULT;
2373
2374 po->origdev = !!val;
2375 return 0;
2376 }
2377 case PACKET_VNET_HDR:
2378 {
2379 int val;
2380
2381 if (sock->type != SOCK_RAW)
2382 return -EINVAL;
2383 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2384 return -EBUSY;
2385 if (optlen < sizeof(val))
2386 return -EINVAL;
2387 if (copy_from_user(&val, optval, sizeof(val)))
2388 return -EFAULT;
2389
2390 po->has_vnet_hdr = !!val;
2391 return 0;
2392 }
2393 case PACKET_TIMESTAMP:
2394 {
2395 int val;
2396
2397 if (optlen != sizeof(val))
2398 return -EINVAL;
2399 if (copy_from_user(&val, optval, sizeof(val)))
2400 return -EFAULT;
2401
2402 po->tp_tstamp = val;
2403 return 0;
2404 }
2405 case PACKET_FANOUT:
2406 {
2407 int val;
2408
2409 if (optlen != sizeof(val))
2410 return -EINVAL;
2411 if (copy_from_user(&val, optval, sizeof(val)))
2412 return -EFAULT;
2413
2414 return fanout_add(sk, val & 0xffff, val >> 16);
2415 }
2416 default:
2417 return -ENOPROTOOPT;
2418 }
2419}
2420
2421static int packet_getsockopt(struct socket *sock, int level, int optname,
2422 char __user *optval, int __user *optlen)
2423{
2424 int len;
2425 int val;
2426 struct sock *sk = sock->sk;
2427 struct packet_sock *po = pkt_sk(sk);
2428 void *data;
2429 struct tpacket_stats st;
2430
2431 if (level != SOL_PACKET)
2432 return -ENOPROTOOPT;
2433
2434 if (get_user(len, optlen))
2435 return -EFAULT;
2436
2437 if (len < 0)
2438 return -EINVAL;
2439
2440 switch (optname) {
2441 case PACKET_STATISTICS:
2442 if (len > sizeof(struct tpacket_stats))
2443 len = sizeof(struct tpacket_stats);
2444 spin_lock_bh(&sk->sk_receive_queue.lock);
2445 st = po->stats;
2446 memset(&po->stats, 0, sizeof(st));
2447 spin_unlock_bh(&sk->sk_receive_queue.lock);
2448 st.tp_packets += st.tp_drops;
2449
2450 data = &st;
2451 break;
2452 case PACKET_AUXDATA:
2453 if (len > sizeof(int))
2454 len = sizeof(int);
2455 val = po->auxdata;
2456
2457 data = &val;
2458 break;
2459 case PACKET_ORIGDEV:
2460 if (len > sizeof(int))
2461 len = sizeof(int);
2462 val = po->origdev;
2463
2464 data = &val;
2465 break;
2466 case PACKET_VNET_HDR:
2467 if (len > sizeof(int))
2468 len = sizeof(int);
2469 val = po->has_vnet_hdr;
2470
2471 data = &val;
2472 break;
2473 case PACKET_VERSION:
2474 if (len > sizeof(int))
2475 len = sizeof(int);
2476 val = po->tp_version;
2477 data = &val;
2478 break;
2479 case PACKET_HDRLEN:
2480 if (len > sizeof(int))
2481 len = sizeof(int);
2482 if (copy_from_user(&val, optval, len))
2483 return -EFAULT;
2484 switch (val) {
2485 case TPACKET_V1:
2486 val = sizeof(struct tpacket_hdr);
2487 break;
2488 case TPACKET_V2:
2489 val = sizeof(struct tpacket2_hdr);
2490 break;
2491 default:
2492 return -EINVAL;
2493 }
2494 data = &val;
2495 break;
2496 case PACKET_RESERVE:
2497 if (len > sizeof(unsigned int))
2498 len = sizeof(unsigned int);
2499 val = po->tp_reserve;
2500 data = &val;
2501 break;
2502 case PACKET_LOSS:
2503 if (len > sizeof(unsigned int))
2504 len = sizeof(unsigned int);
2505 val = po->tp_loss;
2506 data = &val;
2507 break;
2508 case PACKET_TIMESTAMP:
2509 if (len > sizeof(int))
2510 len = sizeof(int);
2511 val = po->tp_tstamp;
2512 data = &val;
2513 break;
2514 case PACKET_FANOUT:
2515 if (len > sizeof(int))
2516 len = sizeof(int);
2517 val = (po->fanout ?
2518 ((u32)po->fanout->id |
2519 ((u32)po->fanout->type << 16)) :
2520 0);
2521 data = &val;
2522 break;
2523 default:
2524 return -ENOPROTOOPT;
2525 }
2526
2527 if (put_user(len, optlen))
2528 return -EFAULT;
2529 if (copy_to_user(optval, data, len))
2530 return -EFAULT;
2531 return 0;
2532}
2533
2534
2535static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
2536{
2537 struct sock *sk;
2538 struct hlist_node *node;
2539 struct net_device *dev = data;
2540 struct net *net = dev_net(dev);
2541
2542 rcu_read_lock();
2543 sk_for_each_rcu(sk, node, &net->packet.sklist) {
2544 struct packet_sock *po = pkt_sk(sk);
2545
2546 switch (msg) {
2547 case NETDEV_UNREGISTER:
2548 if (po->mclist)
2549 packet_dev_mclist(dev, po->mclist, -1);
2550 /* fallthrough */
2551
2552 case NETDEV_DOWN:
2553 if (dev->ifindex == po->ifindex) {
2554 spin_lock(&po->bind_lock);
2555 if (po->running) {
2556 __unregister_prot_hook(sk, false);
2557 sk->sk_err = ENETDOWN;
2558 if (!sock_flag(sk, SOCK_DEAD))
2559 sk->sk_error_report(sk);
2560 }
2561 if (msg == NETDEV_UNREGISTER) {
2562 po->ifindex = -1;
2563 if (po->prot_hook.dev)
2564 dev_put(po->prot_hook.dev);
2565 po->prot_hook.dev = NULL;
2566 }
2567 spin_unlock(&po->bind_lock);
2568 }
2569 break;
2570 case NETDEV_UP:
2571 if (dev->ifindex == po->ifindex) {
2572 spin_lock(&po->bind_lock);
2573 if (po->num)
2574 register_prot_hook(sk);
2575 spin_unlock(&po->bind_lock);
2576 }
2577 break;
2578 }
2579 }
2580 rcu_read_unlock();
2581 return NOTIFY_DONE;
2582}
2583
2584
2585static int packet_ioctl(struct socket *sock, unsigned int cmd,
2586 unsigned long arg)
2587{
2588 struct sock *sk = sock->sk;
2589
2590 switch (cmd) {
2591 case SIOCOUTQ:
2592 {
2593 int amount = sk_wmem_alloc_get(sk);
2594
2595 return put_user(amount, (int __user *)arg);
2596 }
2597 case SIOCINQ:
2598 {
2599 struct sk_buff *skb;
2600 int amount = 0;
2601
2602 spin_lock_bh(&sk->sk_receive_queue.lock);
2603 skb = skb_peek(&sk->sk_receive_queue);
2604 if (skb)
2605 amount = skb->len;
2606 spin_unlock_bh(&sk->sk_receive_queue.lock);
2607 return put_user(amount, (int __user *)arg);
2608 }
2609 case SIOCGSTAMP:
2610 return sock_get_timestamp(sk, (struct timeval __user *)arg);
2611 case SIOCGSTAMPNS:
2612 return sock_get_timestampns(sk, (struct timespec __user *)arg);
2613
2614#ifdef CONFIG_INET
2615 case SIOCADDRT:
2616 case SIOCDELRT:
2617 case SIOCDARP:
2618 case SIOCGARP:
2619 case SIOCSARP:
2620 case SIOCGIFADDR:
2621 case SIOCSIFADDR:
2622 case SIOCGIFBRDADDR:
2623 case SIOCSIFBRDADDR:
2624 case SIOCGIFNETMASK:
2625 case SIOCSIFNETMASK:
2626 case SIOCGIFDSTADDR:
2627 case SIOCSIFDSTADDR:
2628 case SIOCSIFFLAGS:
2629 return inet_dgram_ops.ioctl(sock, cmd, arg);
2630#endif
2631
2632 default:
2633 return -ENOIOCTLCMD;
2634 }
2635 return 0;
2636}
2637
2638static unsigned int packet_poll(struct file *file, struct socket *sock,
2639 poll_table *wait)
2640{
2641 struct sock *sk = sock->sk;
2642 struct packet_sock *po = pkt_sk(sk);
2643 unsigned int mask = datagram_poll(file, sock, wait);
2644
2645 spin_lock_bh(&sk->sk_receive_queue.lock);
2646 if (po->rx_ring.pg_vec) {
2647 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
2648 mask |= POLLIN | POLLRDNORM;
2649 }
2650 spin_unlock_bh(&sk->sk_receive_queue.lock);
2651 spin_lock_bh(&sk->sk_write_queue.lock);
2652 if (po->tx_ring.pg_vec) {
2653 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
2654 mask |= POLLOUT | POLLWRNORM;
2655 }
2656 spin_unlock_bh(&sk->sk_write_queue.lock);
2657 return mask;
2658}
2659
2660
2661/* Dirty? Well, I still did not learn better way to account
2662 * for user mmaps.
2663 */
2664
2665static void packet_mm_open(struct vm_area_struct *vma)
2666{
2667 struct file *file = vma->vm_file;
2668 struct socket *sock = file->private_data;
2669 struct sock *sk = sock->sk;
2670
2671 if (sk)
2672 atomic_inc(&pkt_sk(sk)->mapped);
2673}
2674
2675static void packet_mm_close(struct vm_area_struct *vma)
2676{
2677 struct file *file = vma->vm_file;
2678 struct socket *sock = file->private_data;
2679 struct sock *sk = sock->sk;
2680
2681 if (sk)
2682 atomic_dec(&pkt_sk(sk)->mapped);
2683}
2684
2685static const struct vm_operations_struct packet_mmap_ops = {
2686 .open = packet_mm_open,
2687 .close = packet_mm_close,
2688};
2689
2690static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
2691 unsigned int len)
2692{
2693 int i;
2694
2695 for (i = 0; i < len; i++) {
2696 if (likely(pg_vec[i].buffer)) {
2697 if (is_vmalloc_addr(pg_vec[i].buffer))
2698 vfree(pg_vec[i].buffer);
2699 else
2700 free_pages((unsigned long)pg_vec[i].buffer,
2701 order);
2702 pg_vec[i].buffer = NULL;
2703 }
2704 }
2705 kfree(pg_vec);
2706}
2707
2708static inline char *alloc_one_pg_vec_page(unsigned long order)
2709{
2710 char *buffer = NULL;
2711 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
2712 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
2713
2714 buffer = (char *) __get_free_pages(gfp_flags, order);
2715
2716 if (buffer)
2717 return buffer;
2718
2719 /*
2720 * __get_free_pages failed, fall back to vmalloc
2721 */
2722 buffer = vzalloc((1 << order) * PAGE_SIZE);
2723
2724 if (buffer)
2725 return buffer;
2726
2727 /*
2728 * vmalloc failed, lets dig into swap here
2729 */
2730 gfp_flags &= ~__GFP_NORETRY;
2731 buffer = (char *)__get_free_pages(gfp_flags, order);
2732 if (buffer)
2733 return buffer;
2734
2735 /*
2736 * complete and utter failure
2737 */
2738 return NULL;
2739}
2740
2741static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2742{
2743 unsigned int block_nr = req->tp_block_nr;
2744 struct pgv *pg_vec;
2745 int i;
2746
2747 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2748 if (unlikely(!pg_vec))
2749 goto out;
2750
2751 for (i = 0; i < block_nr; i++) {
2752 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2753 if (unlikely(!pg_vec[i].buffer))
2754 goto out_free_pgvec;
2755 }
2756
2757out:
2758 return pg_vec;
2759
2760out_free_pgvec:
2761 free_pg_vec(pg_vec, order, block_nr);
2762 pg_vec = NULL;
2763 goto out;
2764}
2765
2766static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
2767 int closing, int tx_ring)
2768{
2769 struct pgv *pg_vec = NULL;
2770 struct packet_sock *po = pkt_sk(sk);
2771 int was_running, order = 0;
2772 struct packet_ring_buffer *rb;
2773 struct sk_buff_head *rb_queue;
2774 __be16 num;
2775 int err;
2776
2777 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
2778 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
2779
2780 err = -EBUSY;
2781 if (!closing) {
2782 if (atomic_read(&po->mapped))
2783 goto out;
2784 if (atomic_read(&rb->pending))
2785 goto out;
2786 }
2787
2788 if (req->tp_block_nr) {
2789 /* Sanity tests and some calculations */
2790 err = -EBUSY;
2791 if (unlikely(rb->pg_vec))
2792 goto out;
2793
2794 switch (po->tp_version) {
2795 case TPACKET_V1:
2796 po->tp_hdrlen = TPACKET_HDRLEN;
2797 break;
2798 case TPACKET_V2:
2799 po->tp_hdrlen = TPACKET2_HDRLEN;
2800 break;
2801 }
2802
2803 err = -EINVAL;
2804 if (unlikely((int)req->tp_block_size <= 0))
2805 goto out;
2806 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
2807 goto out;
2808 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
2809 po->tp_reserve))
2810 goto out;
2811 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
2812 goto out;
2813
2814 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
2815 if (unlikely(rb->frames_per_block <= 0))
2816 goto out;
2817 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
2818 req->tp_frame_nr))
2819 goto out;
2820
2821 err = -ENOMEM;
2822 order = get_order(req->tp_block_size);
2823 pg_vec = alloc_pg_vec(req, order);
2824 if (unlikely(!pg_vec))
2825 goto out;
2826 }
2827 /* Done */
2828 else {
2829 err = -EINVAL;
2830 if (unlikely(req->tp_frame_nr))
2831 goto out;
2832 }
2833
2834 lock_sock(sk);
2835
2836 /* Detach socket from network */
2837 spin_lock(&po->bind_lock);
2838 was_running = po->running;
2839 num = po->num;
2840 if (was_running) {
2841 po->num = 0;
2842 __unregister_prot_hook(sk, false);
2843 }
2844 spin_unlock(&po->bind_lock);
2845
2846 synchronize_net();
2847
2848 err = -EBUSY;
2849 mutex_lock(&po->pg_vec_lock);
2850 if (closing || atomic_read(&po->mapped) == 0) {
2851 err = 0;
2852 spin_lock_bh(&rb_queue->lock);
2853 swap(rb->pg_vec, pg_vec);
2854 rb->frame_max = (req->tp_frame_nr - 1);
2855 rb->head = 0;
2856 rb->frame_size = req->tp_frame_size;
2857 spin_unlock_bh(&rb_queue->lock);
2858
2859 swap(rb->pg_vec_order, order);
2860 swap(rb->pg_vec_len, req->tp_block_nr);
2861
2862 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
2863 po->prot_hook.func = (po->rx_ring.pg_vec) ?
2864 tpacket_rcv : packet_rcv;
2865 skb_queue_purge(rb_queue);
2866 if (atomic_read(&po->mapped))
2867 pr_err("packet_mmap: vma is busy: %d\n",
2868 atomic_read(&po->mapped));
2869 }
2870 mutex_unlock(&po->pg_vec_lock);
2871
2872 spin_lock(&po->bind_lock);
2873 if (was_running) {
2874 po->num = num;
2875 register_prot_hook(sk);
2876 }
2877 spin_unlock(&po->bind_lock);
2878
2879 release_sock(sk);
2880
2881 if (pg_vec)
2882 free_pg_vec(pg_vec, order, req->tp_block_nr);
2883out:
2884 return err;
2885}
2886
2887static int packet_mmap(struct file *file, struct socket *sock,
2888 struct vm_area_struct *vma)
2889{
2890 struct sock *sk = sock->sk;
2891 struct packet_sock *po = pkt_sk(sk);
2892 unsigned long size, expected_size;
2893 struct packet_ring_buffer *rb;
2894 unsigned long start;
2895 int err = -EINVAL;
2896 int i;
2897
2898 if (vma->vm_pgoff)
2899 return -EINVAL;
2900
2901 mutex_lock(&po->pg_vec_lock);
2902
2903 expected_size = 0;
2904 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2905 if (rb->pg_vec) {
2906 expected_size += rb->pg_vec_len
2907 * rb->pg_vec_pages
2908 * PAGE_SIZE;
2909 }
2910 }
2911
2912 if (expected_size == 0)
2913 goto out;
2914
2915 size = vma->vm_end - vma->vm_start;
2916 if (size != expected_size)
2917 goto out;
2918
2919 start = vma->vm_start;
2920 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2921 if (rb->pg_vec == NULL)
2922 continue;
2923
2924 for (i = 0; i < rb->pg_vec_len; i++) {
2925 struct page *page;
2926 void *kaddr = rb->pg_vec[i].buffer;
2927 int pg_num;
2928
2929 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
2930 page = pgv_to_page(kaddr);
2931 err = vm_insert_page(vma, start, page);
2932 if (unlikely(err))
2933 goto out;
2934 start += PAGE_SIZE;
2935 kaddr += PAGE_SIZE;
2936 }
2937 }
2938 }
2939
2940 atomic_inc(&po->mapped);
2941 vma->vm_ops = &packet_mmap_ops;
2942 err = 0;
2943
2944out:
2945 mutex_unlock(&po->pg_vec_lock);
2946 return err;
2947}
2948
2949static const struct proto_ops packet_ops_spkt = {
2950 .family = PF_PACKET,
2951 .owner = THIS_MODULE,
2952 .release = packet_release,
2953 .bind = packet_bind_spkt,
2954 .connect = sock_no_connect,
2955 .socketpair = sock_no_socketpair,
2956 .accept = sock_no_accept,
2957 .getname = packet_getname_spkt,
2958 .poll = datagram_poll,
2959 .ioctl = packet_ioctl,
2960 .listen = sock_no_listen,
2961 .shutdown = sock_no_shutdown,
2962 .setsockopt = sock_no_setsockopt,
2963 .getsockopt = sock_no_getsockopt,
2964 .sendmsg = packet_sendmsg_spkt,
2965 .recvmsg = packet_recvmsg,
2966 .mmap = sock_no_mmap,
2967 .sendpage = sock_no_sendpage,
2968};
2969
2970static const struct proto_ops packet_ops = {
2971 .family = PF_PACKET,
2972 .owner = THIS_MODULE,
2973 .release = packet_release,
2974 .bind = packet_bind,
2975 .connect = sock_no_connect,
2976 .socketpair = sock_no_socketpair,
2977 .accept = sock_no_accept,
2978 .getname = packet_getname,
2979 .poll = packet_poll,
2980 .ioctl = packet_ioctl,
2981 .listen = sock_no_listen,
2982 .shutdown = sock_no_shutdown,
2983 .setsockopt = packet_setsockopt,
2984 .getsockopt = packet_getsockopt,
2985 .sendmsg = packet_sendmsg,
2986 .recvmsg = packet_recvmsg,
2987 .mmap = packet_mmap,
2988 .sendpage = sock_no_sendpage,
2989};
2990
2991static const struct net_proto_family packet_family_ops = {
2992 .family = PF_PACKET,
2993 .create = packet_create,
2994 .owner = THIS_MODULE,
2995};
2996
2997static struct notifier_block packet_netdev_notifier = {
2998 .notifier_call = packet_notifier,
2999};
3000
3001#ifdef CONFIG_PROC_FS
3002
3003static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3004 __acquires(RCU)
3005{
3006 struct net *net = seq_file_net(seq);
3007
3008 rcu_read_lock();
3009 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3010}
3011
3012static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3013{
3014 struct net *net = seq_file_net(seq);
3015 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3016}
3017
3018static void packet_seq_stop(struct seq_file *seq, void *v)
3019 __releases(RCU)
3020{
3021 rcu_read_unlock();
3022}
3023
3024static int packet_seq_show(struct seq_file *seq, void *v)
3025{
3026 if (v == SEQ_START_TOKEN)
3027 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3028 else {
3029 struct sock *s = sk_entry(v);
3030 const struct packet_sock *po = pkt_sk(s);
3031
3032 seq_printf(seq,
3033 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3034 s,
3035 atomic_read(&s->sk_refcnt),
3036 s->sk_type,
3037 ntohs(po->num),
3038 po->ifindex,
3039 po->running,
3040 atomic_read(&s->sk_rmem_alloc),
3041 sock_i_uid(s),
3042 sock_i_ino(s));
3043 }
3044
3045 return 0;
3046}
3047
3048static const struct seq_operations packet_seq_ops = {
3049 .start = packet_seq_start,
3050 .next = packet_seq_next,
3051 .stop = packet_seq_stop,
3052 .show = packet_seq_show,
3053};
3054
3055static int packet_seq_open(struct inode *inode, struct file *file)
3056{
3057 return seq_open_net(inode, file, &packet_seq_ops,
3058 sizeof(struct seq_net_private));
3059}
3060
3061static const struct file_operations packet_seq_fops = {
3062 .owner = THIS_MODULE,
3063 .open = packet_seq_open,
3064 .read = seq_read,
3065 .llseek = seq_lseek,
3066 .release = seq_release_net,
3067};
3068
3069#endif
3070
3071static int __net_init packet_net_init(struct net *net)
3072{
3073 spin_lock_init(&net->packet.sklist_lock);
3074 INIT_HLIST_HEAD(&net->packet.sklist);
3075
3076 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3077 return -ENOMEM;
3078
3079 return 0;
3080}
3081
3082static void __net_exit packet_net_exit(struct net *net)
3083{
3084 proc_net_remove(net, "packet");
3085}
3086
3087static struct pernet_operations packet_net_ops = {
3088 .init = packet_net_init,
3089 .exit = packet_net_exit,
3090};
3091
3092
3093static void __exit packet_exit(void)
3094{
3095 unregister_netdevice_notifier(&packet_netdev_notifier);
3096 unregister_pernet_subsys(&packet_net_ops);
3097 sock_unregister(PF_PACKET);
3098 proto_unregister(&packet_proto);
3099}
3100
3101static int __init packet_init(void)
3102{
3103 int rc = proto_register(&packet_proto, 0);
3104
3105 if (rc != 0)
3106 goto out;
3107
3108 sock_register(&packet_family_ops);
3109 register_pernet_subsys(&packet_net_ops);
3110 register_netdevice_notifier(&packet_netdev_notifier);
3111out:
3112 return rc;
3113}
3114
3115module_init(packet_init);
3116module_exit(packet_exit);
3117MODULE_LICENSE("GPL");
3118MODULE_ALIAS_NETPROTO(PF_PACKET);