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import PULS_20180308
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / packet / af_packet.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * PACKET - implements raw packet sockets.
7 *
8 * 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
92 #ifdef CONFIG_INET
93 #include <net/inet_common.h>
94 #endif
95
96 #include "internal.h"
97
98 /*
99 Assumptions:
100 - if device has no dev->hard_header routine, it adds and removes ll header
101 inside itself. In this case ll header is invisible outside of device,
102 but higher levels still should reserve dev->hard_header_len.
103 Some devices are enough clever to reallocate skb, when header
104 will not fit to reserved space (tunnel), another ones are silly
105 (PPP).
106 - packet socket receives packets with pulled ll header,
107 so that SOCK_RAW should push it back.
108
109 On receive:
110 -----------
111
112 Incoming, dev->hard_header!=NULL
113 mac_header -> ll header
114 data -> data
115
116 Outgoing, dev->hard_header!=NULL
117 mac_header -> ll header
118 data -> ll header
119
120 Incoming, dev->hard_header==NULL
121 mac_header -> UNKNOWN position. It is very likely, that it points to ll
122 header. PPP makes it, that is wrong, because introduce
123 assymetry between rx and tx paths.
124 data -> data
125
126 Outgoing, dev->hard_header==NULL
127 mac_header -> data. ll header is still not built!
128 data -> data
129
130 Resume
131 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
132
133
134 On transmit:
135 ------------
136
137 dev->hard_header != NULL
138 mac_header -> ll header
139 data -> ll header
140
141 dev->hard_header == NULL (ll header is added by device, we cannot control it)
142 mac_header -> data
143 data -> data
144
145 We should set nh.raw on output to correct posistion,
146 packet classifier depends on it.
147 */
148
149 /* Private packet socket structures. */
150
151 /* identical to struct packet_mreq except it has
152 * a longer address field.
153 */
154 struct packet_mreq_max {
155 int mr_ifindex;
156 unsigned short mr_type;
157 unsigned short mr_alen;
158 unsigned char mr_address[MAX_ADDR_LEN];
159 };
160
161 union tpacket_uhdr {
162 struct tpacket_hdr *h1;
163 struct tpacket2_hdr *h2;
164 struct tpacket3_hdr *h3;
165 void *raw;
166 };
167
168 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
169 int closing, int tx_ring);
170
171 #define V3_ALIGNMENT (8)
172
173 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
174
175 #define BLK_PLUS_PRIV(sz_of_priv) \
176 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
177
178 #define PGV_FROM_VMALLOC 1
179
180 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
181 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
182 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
183 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
184 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
185 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
186 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
187
188 struct packet_sock;
189 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
190 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
191 struct packet_type *pt, struct net_device *orig_dev);
192
193 static void *packet_previous_frame(struct packet_sock *po,
194 struct packet_ring_buffer *rb,
195 int status);
196 static void packet_increment_head(struct packet_ring_buffer *buff);
197 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
198 struct tpacket_block_desc *);
199 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
200 struct packet_sock *);
201 static void prb_retire_current_block(struct tpacket_kbdq_core *,
202 struct packet_sock *, unsigned int status);
203 static int prb_queue_frozen(struct tpacket_kbdq_core *);
204 static void prb_open_block(struct tpacket_kbdq_core *,
205 struct tpacket_block_desc *);
206 static void prb_retire_rx_blk_timer_expired(unsigned long);
207 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
208 static void prb_init_blk_timer(struct packet_sock *,
209 struct tpacket_kbdq_core *,
210 void (*func) (unsigned long));
211 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
212 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
213 struct tpacket3_hdr *);
214 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
215 struct tpacket3_hdr *);
216 static void packet_flush_mclist(struct sock *sk);
217
218 struct packet_skb_cb {
219 unsigned int origlen;
220 union {
221 struct sockaddr_pkt pkt;
222 struct sockaddr_ll ll;
223 } sa;
224 };
225
226 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
227
228 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
229 #define GET_PBLOCK_DESC(x, bid) \
230 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
231 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
232 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
233 #define GET_NEXT_PRB_BLK_NUM(x) \
234 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
235 ((x)->kactive_blk_num+1) : 0)
236
237 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
238 static void __fanout_link(struct sock *sk, struct packet_sock *po);
239
240 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
241 {
242 struct net_device *dev;
243
244 rcu_read_lock();
245 dev = rcu_dereference(po->cached_dev);
246 if (likely(dev))
247 dev_hold(dev);
248 rcu_read_unlock();
249
250 return dev;
251 }
252
253 static void packet_cached_dev_assign(struct packet_sock *po,
254 struct net_device *dev)
255 {
256 rcu_assign_pointer(po->cached_dev, dev);
257 }
258
259 static void packet_cached_dev_reset(struct packet_sock *po)
260 {
261 RCU_INIT_POINTER(po->cached_dev, NULL);
262 }
263
264 /* register_prot_hook must be invoked with the po->bind_lock held,
265 * or from a context in which asynchronous accesses to the packet
266 * socket is not possible (packet_create()).
267 */
268 static void register_prot_hook(struct sock *sk)
269 {
270 struct packet_sock *po = pkt_sk(sk);
271
272 if (!po->running) {
273 if (po->fanout)
274 __fanout_link(sk, po);
275 else
276 dev_add_pack(&po->prot_hook);
277
278 sock_hold(sk);
279 po->running = 1;
280 }
281 }
282
283 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
284 * held. If the sync parameter is true, we will temporarily drop
285 * the po->bind_lock and do a synchronize_net to make sure no
286 * asynchronous packet processing paths still refer to the elements
287 * of po->prot_hook. If the sync parameter is false, it is the
288 * callers responsibility to take care of this.
289 */
290 static void __unregister_prot_hook(struct sock *sk, bool sync)
291 {
292 struct packet_sock *po = pkt_sk(sk);
293
294 po->running = 0;
295
296 if (po->fanout)
297 __fanout_unlink(sk, po);
298 else
299 __dev_remove_pack(&po->prot_hook);
300
301 __sock_put(sk);
302
303 if (sync) {
304 spin_unlock(&po->bind_lock);
305 synchronize_net();
306 spin_lock(&po->bind_lock);
307 }
308 }
309
310 static void unregister_prot_hook(struct sock *sk, bool sync)
311 {
312 struct packet_sock *po = pkt_sk(sk);
313
314 if (po->running)
315 __unregister_prot_hook(sk, sync);
316 }
317
318 static inline __pure struct page *pgv_to_page(void *addr)
319 {
320 if (is_vmalloc_addr(addr))
321 return vmalloc_to_page(addr);
322 return virt_to_page(addr);
323 }
324
325 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
326 {
327 union tpacket_uhdr h;
328
329 h.raw = frame;
330 switch (po->tp_version) {
331 case TPACKET_V1:
332 h.h1->tp_status = status;
333 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
334 break;
335 case TPACKET_V2:
336 h.h2->tp_status = status;
337 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
338 break;
339 case TPACKET_V3:
340 default:
341 WARN(1, "TPACKET version not supported.\n");
342 BUG();
343 }
344
345 smp_wmb();
346 }
347
348 static int __packet_get_status(struct packet_sock *po, void *frame)
349 {
350 union tpacket_uhdr h;
351
352 smp_rmb();
353
354 h.raw = frame;
355 switch (po->tp_version) {
356 case TPACKET_V1:
357 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
358 return h.h1->tp_status;
359 case TPACKET_V2:
360 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
361 return h.h2->tp_status;
362 case TPACKET_V3:
363 default:
364 WARN(1, "TPACKET version not supported.\n");
365 BUG();
366 return 0;
367 }
368 }
369
370 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
371 unsigned int flags)
372 {
373 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
374
375 if (shhwtstamps) {
376 if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
377 ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
378 return TP_STATUS_TS_SYS_HARDWARE;
379 if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
380 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
381 return TP_STATUS_TS_RAW_HARDWARE;
382 }
383
384 if (ktime_to_timespec_cond(skb->tstamp, ts))
385 return TP_STATUS_TS_SOFTWARE;
386
387 return 0;
388 }
389
390 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
391 struct sk_buff *skb)
392 {
393 union tpacket_uhdr h;
394 struct timespec ts;
395 __u32 ts_status;
396
397 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
398 return 0;
399
400 h.raw = frame;
401 switch (po->tp_version) {
402 case TPACKET_V1:
403 h.h1->tp_sec = ts.tv_sec;
404 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
405 break;
406 case TPACKET_V2:
407 h.h2->tp_sec = ts.tv_sec;
408 h.h2->tp_nsec = ts.tv_nsec;
409 break;
410 case TPACKET_V3:
411 default:
412 WARN(1, "TPACKET version not supported.\n");
413 BUG();
414 }
415
416 /* one flush is safe, as both fields always lie on the same cacheline */
417 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
418 smp_wmb();
419
420 return ts_status;
421 }
422
423 static void *packet_lookup_frame(struct packet_sock *po,
424 struct packet_ring_buffer *rb,
425 unsigned int position,
426 int status)
427 {
428 unsigned int pg_vec_pos, frame_offset;
429 union tpacket_uhdr h;
430
431 pg_vec_pos = position / rb->frames_per_block;
432 frame_offset = position % rb->frames_per_block;
433
434 h.raw = rb->pg_vec[pg_vec_pos].buffer +
435 (frame_offset * rb->frame_size);
436
437 if (status != __packet_get_status(po, h.raw))
438 return NULL;
439
440 return h.raw;
441 }
442
443 static void *packet_current_frame(struct packet_sock *po,
444 struct packet_ring_buffer *rb,
445 int status)
446 {
447 return packet_lookup_frame(po, rb, rb->head, status);
448 }
449
450 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
451 {
452 del_timer_sync(&pkc->retire_blk_timer);
453 }
454
455 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
456 int tx_ring,
457 struct sk_buff_head *rb_queue)
458 {
459 struct tpacket_kbdq_core *pkc;
460
461 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
462
463 spin_lock_bh(&rb_queue->lock);
464 pkc->delete_blk_timer = 1;
465 spin_unlock_bh(&rb_queue->lock);
466
467 prb_del_retire_blk_timer(pkc);
468 }
469
470 static void prb_init_blk_timer(struct packet_sock *po,
471 struct tpacket_kbdq_core *pkc,
472 void (*func) (unsigned long))
473 {
474 init_timer(&pkc->retire_blk_timer);
475 pkc->retire_blk_timer.data = (long)po;
476 pkc->retire_blk_timer.function = func;
477 pkc->retire_blk_timer.expires = jiffies;
478 }
479
480 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
481 {
482 struct tpacket_kbdq_core *pkc;
483
484 if (tx_ring)
485 BUG();
486
487 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
488 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
489 }
490
491 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
492 int blk_size_in_bytes)
493 {
494 struct net_device *dev;
495 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
496 struct ethtool_cmd ecmd;
497 int err;
498 u32 speed;
499
500 rtnl_lock();
501 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
502 if (unlikely(!dev)) {
503 rtnl_unlock();
504 return DEFAULT_PRB_RETIRE_TOV;
505 }
506 err = __ethtool_get_settings(dev, &ecmd);
507 speed = ethtool_cmd_speed(&ecmd);
508 rtnl_unlock();
509 if (!err) {
510 /*
511 * If the link speed is so slow you don't really
512 * need to worry about perf anyways
513 */
514 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
515 return DEFAULT_PRB_RETIRE_TOV;
516 } else {
517 msec = 1;
518 div = speed / 1000;
519 }
520 }
521
522 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
523
524 if (div)
525 mbits /= div;
526
527 tmo = mbits * msec;
528
529 if (div)
530 return tmo+1;
531 return tmo;
532 }
533
534 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
535 union tpacket_req_u *req_u)
536 {
537 p1->feature_req_word = req_u->req3.tp_feature_req_word;
538 }
539
540 static void init_prb_bdqc(struct packet_sock *po,
541 struct packet_ring_buffer *rb,
542 struct pgv *pg_vec,
543 union tpacket_req_u *req_u, int tx_ring)
544 {
545 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
546 struct tpacket_block_desc *pbd;
547
548 memset(p1, 0x0, sizeof(*p1));
549
550 p1->knxt_seq_num = 1;
551 p1->pkbdq = pg_vec;
552 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
553 p1->pkblk_start = pg_vec[0].buffer;
554 p1->kblk_size = req_u->req3.tp_block_size;
555 p1->knum_blocks = req_u->req3.tp_block_nr;
556 p1->hdrlen = po->tp_hdrlen;
557 p1->version = po->tp_version;
558 p1->last_kactive_blk_num = 0;
559 po->stats.stats3.tp_freeze_q_cnt = 0;
560 if (req_u->req3.tp_retire_blk_tov)
561 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
562 else
563 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
564 req_u->req3.tp_block_size);
565 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
566 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
567
568 prb_init_ft_ops(p1, req_u);
569 prb_setup_retire_blk_timer(po, tx_ring);
570 prb_open_block(p1, pbd);
571 }
572
573 /* Do NOT update the last_blk_num first.
574 * Assumes sk_buff_head lock is held.
575 */
576 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
577 {
578 mod_timer(&pkc->retire_blk_timer,
579 jiffies + pkc->tov_in_jiffies);
580 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
581 }
582
583 /*
584 * Timer logic:
585 * 1) We refresh the timer only when we open a block.
586 * By doing this we don't waste cycles refreshing the timer
587 * on packet-by-packet basis.
588 *
589 * With a 1MB block-size, on a 1Gbps line, it will take
590 * i) ~8 ms to fill a block + ii) memcpy etc.
591 * In this cut we are not accounting for the memcpy time.
592 *
593 * So, if the user sets the 'tmo' to 10ms then the timer
594 * will never fire while the block is still getting filled
595 * (which is what we want). However, the user could choose
596 * to close a block early and that's fine.
597 *
598 * But when the timer does fire, we check whether or not to refresh it.
599 * Since the tmo granularity is in msecs, it is not too expensive
600 * to refresh the timer, lets say every '8' msecs.
601 * Either the user can set the 'tmo' or we can derive it based on
602 * a) line-speed and b) block-size.
603 * prb_calc_retire_blk_tmo() calculates the tmo.
604 *
605 */
606 static void prb_retire_rx_blk_timer_expired(unsigned long data)
607 {
608 struct packet_sock *po = (struct packet_sock *)data;
609 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
610 unsigned int frozen;
611 struct tpacket_block_desc *pbd;
612
613 spin_lock(&po->sk.sk_receive_queue.lock);
614
615 frozen = prb_queue_frozen(pkc);
616 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
617
618 if (unlikely(pkc->delete_blk_timer))
619 goto out;
620
621 /* We only need to plug the race when the block is partially filled.
622 * tpacket_rcv:
623 * lock(); increment BLOCK_NUM_PKTS; unlock()
624 * copy_bits() is in progress ...
625 * timer fires on other cpu:
626 * we can't retire the current block because copy_bits
627 * is in progress.
628 *
629 */
630 if (BLOCK_NUM_PKTS(pbd)) {
631 while (atomic_read(&pkc->blk_fill_in_prog)) {
632 /* Waiting for skb_copy_bits to finish... */
633 cpu_relax();
634 }
635 }
636
637 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
638 if (!frozen) {
639 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
640 if (!prb_dispatch_next_block(pkc, po))
641 goto refresh_timer;
642 else
643 goto out;
644 } else {
645 /* Case 1. Queue was frozen because user-space was
646 * lagging behind.
647 */
648 if (prb_curr_blk_in_use(pkc, pbd)) {
649 /*
650 * Ok, user-space is still behind.
651 * So just refresh the timer.
652 */
653 goto refresh_timer;
654 } else {
655 /* Case 2. queue was frozen,user-space caught up,
656 * now the link went idle && the timer fired.
657 * We don't have a block to close.So we open this
658 * block and restart the timer.
659 * opening a block thaws the queue,restarts timer
660 * Thawing/timer-refresh is a side effect.
661 */
662 prb_open_block(pkc, pbd);
663 goto out;
664 }
665 }
666 }
667
668 refresh_timer:
669 _prb_refresh_rx_retire_blk_timer(pkc);
670
671 out:
672 spin_unlock(&po->sk.sk_receive_queue.lock);
673 }
674
675 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
676 struct tpacket_block_desc *pbd1, __u32 status)
677 {
678 /* Flush everything minus the block header */
679
680 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
681 u8 *start, *end;
682
683 start = (u8 *)pbd1;
684
685 /* Skip the block header(we know header WILL fit in 4K) */
686 start += PAGE_SIZE;
687
688 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
689 for (; start < end; start += PAGE_SIZE)
690 flush_dcache_page(pgv_to_page(start));
691
692 smp_wmb();
693 #endif
694
695 /* Now update the block status. */
696
697 BLOCK_STATUS(pbd1) = status;
698
699 /* Flush the block header */
700
701 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
702 start = (u8 *)pbd1;
703 flush_dcache_page(pgv_to_page(start));
704
705 smp_wmb();
706 #endif
707 }
708
709 /*
710 * Side effect:
711 *
712 * 1) flush the block
713 * 2) Increment active_blk_num
714 *
715 * Note:We DONT refresh the timer on purpose.
716 * Because almost always the next block will be opened.
717 */
718 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
719 struct tpacket_block_desc *pbd1,
720 struct packet_sock *po, unsigned int stat)
721 {
722 __u32 status = TP_STATUS_USER | stat;
723
724 struct tpacket3_hdr *last_pkt;
725 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
726
727 if (po->stats.stats3.tp_drops)
728 status |= TP_STATUS_LOSING;
729
730 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
731 last_pkt->tp_next_offset = 0;
732
733 /* Get the ts of the last pkt */
734 if (BLOCK_NUM_PKTS(pbd1)) {
735 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
736 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
737 } else {
738 /* Ok, we tmo'd - so get the current time */
739 struct timespec ts;
740 getnstimeofday(&ts);
741 h1->ts_last_pkt.ts_sec = ts.tv_sec;
742 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
743 }
744
745 smp_wmb();
746
747 /* Flush the block */
748 prb_flush_block(pkc1, pbd1, status);
749
750 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
751 }
752
753 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
754 {
755 pkc->reset_pending_on_curr_blk = 0;
756 }
757
758 /*
759 * Side effect of opening a block:
760 *
761 * 1) prb_queue is thawed.
762 * 2) retire_blk_timer is refreshed.
763 *
764 */
765 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
766 struct tpacket_block_desc *pbd1)
767 {
768 struct timespec ts;
769 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
770
771 smp_rmb();
772
773 /* We could have just memset this but we will lose the
774 * flexibility of making the priv area sticky
775 */
776
777 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
778 BLOCK_NUM_PKTS(pbd1) = 0;
779 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
780
781 getnstimeofday(&ts);
782
783 h1->ts_first_pkt.ts_sec = ts.tv_sec;
784 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
785
786 pkc1->pkblk_start = (char *)pbd1;
787 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
788
789 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
790 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
791
792 pbd1->version = pkc1->version;
793 pkc1->prev = pkc1->nxt_offset;
794 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
795
796 prb_thaw_queue(pkc1);
797 _prb_refresh_rx_retire_blk_timer(pkc1);
798
799 smp_wmb();
800 }
801
802 /*
803 * Queue freeze logic:
804 * 1) Assume tp_block_nr = 8 blocks.
805 * 2) At time 't0', user opens Rx ring.
806 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
807 * 4) user-space is either sleeping or processing block '0'.
808 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
809 * it will close block-7,loop around and try to fill block '0'.
810 * call-flow:
811 * __packet_lookup_frame_in_block
812 * prb_retire_current_block()
813 * prb_dispatch_next_block()
814 * |->(BLOCK_STATUS == USER) evaluates to true
815 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
816 * 6) Now there are two cases:
817 * 6.1) Link goes idle right after the queue is frozen.
818 * But remember, the last open_block() refreshed the timer.
819 * When this timer expires,it will refresh itself so that we can
820 * re-open block-0 in near future.
821 * 6.2) Link is busy and keeps on receiving packets. This is a simple
822 * case and __packet_lookup_frame_in_block will check if block-0
823 * is free and can now be re-used.
824 */
825 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
826 struct packet_sock *po)
827 {
828 pkc->reset_pending_on_curr_blk = 1;
829 po->stats.stats3.tp_freeze_q_cnt++;
830 }
831
832 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
833
834 /*
835 * If the next block is free then we will dispatch it
836 * and return a good offset.
837 * Else, we will freeze the queue.
838 * So, caller must check the return value.
839 */
840 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
841 struct packet_sock *po)
842 {
843 struct tpacket_block_desc *pbd;
844
845 smp_rmb();
846
847 /* 1. Get current block num */
848 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
849
850 /* 2. If this block is currently in_use then freeze the queue */
851 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
852 prb_freeze_queue(pkc, po);
853 return NULL;
854 }
855
856 /*
857 * 3.
858 * open this block and return the offset where the first packet
859 * needs to get stored.
860 */
861 prb_open_block(pkc, pbd);
862 return (void *)pkc->nxt_offset;
863 }
864
865 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
866 struct packet_sock *po, unsigned int status)
867 {
868 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
869
870 /* retire/close the current block */
871 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
872 /*
873 * Plug the case where copy_bits() is in progress on
874 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
875 * have space to copy the pkt in the current block and
876 * called prb_retire_current_block()
877 *
878 * We don't need to worry about the TMO case because
879 * the timer-handler already handled this case.
880 */
881 if (!(status & TP_STATUS_BLK_TMO)) {
882 while (atomic_read(&pkc->blk_fill_in_prog)) {
883 /* Waiting for skb_copy_bits to finish... */
884 cpu_relax();
885 }
886 }
887 prb_close_block(pkc, pbd, po, status);
888 return;
889 }
890 }
891
892 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
893 struct tpacket_block_desc *pbd)
894 {
895 return TP_STATUS_USER & BLOCK_STATUS(pbd);
896 }
897
898 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
899 {
900 return pkc->reset_pending_on_curr_blk;
901 }
902
903 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
904 {
905 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
906 atomic_dec(&pkc->blk_fill_in_prog);
907 }
908
909 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
910 struct tpacket3_hdr *ppd)
911 {
912 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
913 }
914
915 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
916 struct tpacket3_hdr *ppd)
917 {
918 ppd->hv1.tp_rxhash = 0;
919 }
920
921 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
922 struct tpacket3_hdr *ppd)
923 {
924 if (vlan_tx_tag_present(pkc->skb)) {
925 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
926 ppd->tp_status = TP_STATUS_VLAN_VALID;
927 } else {
928 ppd->hv1.tp_vlan_tci = 0;
929 ppd->tp_status = TP_STATUS_AVAILABLE;
930 }
931 }
932
933 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
934 struct tpacket3_hdr *ppd)
935 {
936 prb_fill_vlan_info(pkc, ppd);
937
938 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
939 prb_fill_rxhash(pkc, ppd);
940 else
941 prb_clear_rxhash(pkc, ppd);
942 }
943
944 static void prb_fill_curr_block(char *curr,
945 struct tpacket_kbdq_core *pkc,
946 struct tpacket_block_desc *pbd,
947 unsigned int len)
948 {
949 struct tpacket3_hdr *ppd;
950
951 ppd = (struct tpacket3_hdr *)curr;
952 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
953 pkc->prev = curr;
954 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
955 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
956 BLOCK_NUM_PKTS(pbd) += 1;
957 atomic_inc(&pkc->blk_fill_in_prog);
958 prb_run_all_ft_ops(pkc, ppd);
959 }
960
961 /* Assumes caller has the sk->rx_queue.lock */
962 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
963 struct sk_buff *skb,
964 int status,
965 unsigned int len
966 )
967 {
968 struct tpacket_kbdq_core *pkc;
969 struct tpacket_block_desc *pbd;
970 char *curr, *end;
971
972 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
973 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
974
975 /* Queue is frozen when user space is lagging behind */
976 if (prb_queue_frozen(pkc)) {
977 /*
978 * Check if that last block which caused the queue to freeze,
979 * is still in_use by user-space.
980 */
981 if (prb_curr_blk_in_use(pkc, pbd)) {
982 /* Can't record this packet */
983 return NULL;
984 } else {
985 /*
986 * Ok, the block was released by user-space.
987 * Now let's open that block.
988 * opening a block also thaws the queue.
989 * Thawing is a side effect.
990 */
991 prb_open_block(pkc, pbd);
992 }
993 }
994
995 smp_mb();
996 curr = pkc->nxt_offset;
997 pkc->skb = skb;
998 end = (char *)pbd + pkc->kblk_size;
999
1000 /* first try the current block */
1001 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1002 prb_fill_curr_block(curr, pkc, pbd, len);
1003 return (void *)curr;
1004 }
1005
1006 /* Ok, close the current block */
1007 prb_retire_current_block(pkc, po, 0);
1008
1009 /* Now, try to dispatch the next block */
1010 curr = (char *)prb_dispatch_next_block(pkc, po);
1011 if (curr) {
1012 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1013 prb_fill_curr_block(curr, pkc, pbd, len);
1014 return (void *)curr;
1015 }
1016
1017 /*
1018 * No free blocks are available.user_space hasn't caught up yet.
1019 * Queue was just frozen and now this packet will get dropped.
1020 */
1021 return NULL;
1022 }
1023
1024 static void *packet_current_rx_frame(struct packet_sock *po,
1025 struct sk_buff *skb,
1026 int status, unsigned int len)
1027 {
1028 char *curr = NULL;
1029 switch (po->tp_version) {
1030 case TPACKET_V1:
1031 case TPACKET_V2:
1032 curr = packet_lookup_frame(po, &po->rx_ring,
1033 po->rx_ring.head, status);
1034 return curr;
1035 case TPACKET_V3:
1036 return __packet_lookup_frame_in_block(po, skb, status, len);
1037 default:
1038 WARN(1, "TPACKET version not supported\n");
1039 BUG();
1040 return NULL;
1041 }
1042 }
1043
1044 static void *prb_lookup_block(struct packet_sock *po,
1045 struct packet_ring_buffer *rb,
1046 unsigned int idx,
1047 int status)
1048 {
1049 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1050 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1051
1052 if (status != BLOCK_STATUS(pbd))
1053 return NULL;
1054 return pbd;
1055 }
1056
1057 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1058 {
1059 unsigned int prev;
1060 if (rb->prb_bdqc.kactive_blk_num)
1061 prev = rb->prb_bdqc.kactive_blk_num-1;
1062 else
1063 prev = rb->prb_bdqc.knum_blocks-1;
1064 return prev;
1065 }
1066
1067 /* Assumes caller has held the rx_queue.lock */
1068 static void *__prb_previous_block(struct packet_sock *po,
1069 struct packet_ring_buffer *rb,
1070 int status)
1071 {
1072 unsigned int previous = prb_previous_blk_num(rb);
1073 return prb_lookup_block(po, rb, previous, status);
1074 }
1075
1076 static void *packet_previous_rx_frame(struct packet_sock *po,
1077 struct packet_ring_buffer *rb,
1078 int status)
1079 {
1080 if (po->tp_version <= TPACKET_V2)
1081 return packet_previous_frame(po, rb, status);
1082
1083 return __prb_previous_block(po, rb, status);
1084 }
1085
1086 static void packet_increment_rx_head(struct packet_sock *po,
1087 struct packet_ring_buffer *rb)
1088 {
1089 switch (po->tp_version) {
1090 case TPACKET_V1:
1091 case TPACKET_V2:
1092 return packet_increment_head(rb);
1093 case TPACKET_V3:
1094 default:
1095 WARN(1, "TPACKET version not supported.\n");
1096 BUG();
1097 return;
1098 }
1099 }
1100
1101 static void *packet_previous_frame(struct packet_sock *po,
1102 struct packet_ring_buffer *rb,
1103 int status)
1104 {
1105 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1106 return packet_lookup_frame(po, rb, previous, status);
1107 }
1108
1109 static void packet_increment_head(struct packet_ring_buffer *buff)
1110 {
1111 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1112 }
1113
1114 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1115 {
1116 struct sock *sk = &po->sk;
1117 bool has_room;
1118
1119 if (po->prot_hook.func != tpacket_rcv)
1120 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1121 <= sk->sk_rcvbuf;
1122
1123 spin_lock(&sk->sk_receive_queue.lock);
1124 if (po->tp_version == TPACKET_V3)
1125 has_room = prb_lookup_block(po, &po->rx_ring,
1126 po->rx_ring.prb_bdqc.kactive_blk_num,
1127 TP_STATUS_KERNEL);
1128 else
1129 has_room = packet_lookup_frame(po, &po->rx_ring,
1130 po->rx_ring.head,
1131 TP_STATUS_KERNEL);
1132 spin_unlock(&sk->sk_receive_queue.lock);
1133
1134 return has_room;
1135 }
1136
1137 static void packet_sock_destruct(struct sock *sk)
1138 {
1139 skb_queue_purge(&sk->sk_error_queue);
1140
1141 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1142 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1143
1144 if (!sock_flag(sk, SOCK_DEAD)) {
1145 pr_err("Attempt to release alive packet socket: %p\n", sk);
1146 return;
1147 }
1148
1149 sk_refcnt_debug_dec(sk);
1150 }
1151
1152 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1153 {
1154 int x = atomic_read(&f->rr_cur) + 1;
1155
1156 if (x >= num)
1157 x = 0;
1158
1159 return x;
1160 }
1161
1162 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1163 struct sk_buff *skb,
1164 unsigned int num)
1165 {
1166 return (((u64)skb->rxhash) * num) >> 32;
1167 }
1168
1169 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1170 struct sk_buff *skb,
1171 unsigned int num)
1172 {
1173 int cur, old;
1174
1175 cur = atomic_read(&f->rr_cur);
1176 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1177 fanout_rr_next(f, num))) != cur)
1178 cur = old;
1179 return cur;
1180 }
1181
1182 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1183 struct sk_buff *skb,
1184 unsigned int num)
1185 {
1186 return smp_processor_id() % num;
1187 }
1188
1189 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1190 struct sk_buff *skb,
1191 unsigned int idx, unsigned int skip,
1192 unsigned int num)
1193 {
1194 unsigned int i, j;
1195
1196 i = j = min_t(int, f->next[idx], num - 1);
1197 do {
1198 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1199 if (i != j)
1200 f->next[idx] = i;
1201 return i;
1202 }
1203 if (++i == num)
1204 i = 0;
1205 } while (i != j);
1206
1207 return idx;
1208 }
1209
1210 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1211 {
1212 return f->flags & (flag >> 8);
1213 }
1214
1215 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1216 struct packet_type *pt, struct net_device *orig_dev)
1217 {
1218 struct packet_fanout *f = pt->af_packet_priv;
1219 unsigned int num = f->num_members;
1220 struct packet_sock *po;
1221 unsigned int idx;
1222
1223 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1224 !num) {
1225 kfree_skb(skb);
1226 return 0;
1227 }
1228
1229 switch (f->type) {
1230 case PACKET_FANOUT_HASH:
1231 default:
1232 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1233 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1234 if (!skb)
1235 return 0;
1236 }
1237 skb_get_rxhash(skb);
1238 idx = fanout_demux_hash(f, skb, num);
1239 break;
1240 case PACKET_FANOUT_LB:
1241 idx = fanout_demux_lb(f, skb, num);
1242 break;
1243 case PACKET_FANOUT_CPU:
1244 idx = fanout_demux_cpu(f, skb, num);
1245 break;
1246 case PACKET_FANOUT_ROLLOVER:
1247 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1248 break;
1249 }
1250
1251 po = pkt_sk(f->arr[idx]);
1252 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1253 unlikely(!packet_rcv_has_room(po, skb))) {
1254 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1255 po = pkt_sk(f->arr[idx]);
1256 }
1257
1258 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1259 }
1260
1261 DEFINE_MUTEX(fanout_mutex);
1262 EXPORT_SYMBOL_GPL(fanout_mutex);
1263 static LIST_HEAD(fanout_list);
1264
1265 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1266 {
1267 struct packet_fanout *f = po->fanout;
1268
1269 spin_lock(&f->lock);
1270 f->arr[f->num_members] = sk;
1271 smp_wmb();
1272 f->num_members++;
1273 spin_unlock(&f->lock);
1274 }
1275
1276 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1277 {
1278 struct packet_fanout *f = po->fanout;
1279 int i;
1280
1281 spin_lock(&f->lock);
1282 for (i = 0; i < f->num_members; i++) {
1283 if (f->arr[i] == sk)
1284 break;
1285 }
1286 BUG_ON(i >= f->num_members);
1287 f->arr[i] = f->arr[f->num_members - 1];
1288 f->num_members--;
1289 spin_unlock(&f->lock);
1290 }
1291
1292 static bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
1293 {
1294 if (ptype->af_packet_priv == (void*)((struct packet_sock *)sk)->fanout)
1295 return true;
1296
1297 return false;
1298 }
1299
1300 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1301 {
1302 struct packet_sock *po = pkt_sk(sk);
1303 struct packet_fanout *f, *match;
1304 u8 type = type_flags & 0xff;
1305 u8 flags = type_flags >> 8;
1306 int err;
1307
1308 switch (type) {
1309 case PACKET_FANOUT_ROLLOVER:
1310 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1311 return -EINVAL;
1312 case PACKET_FANOUT_HASH:
1313 case PACKET_FANOUT_LB:
1314 case PACKET_FANOUT_CPU:
1315 break;
1316 default:
1317 return -EINVAL;
1318 }
1319
1320 if (!po->running)
1321 return -EINVAL;
1322
1323 if (po->fanout)
1324 return -EALREADY;
1325
1326 mutex_lock(&fanout_mutex);
1327 match = NULL;
1328 list_for_each_entry(f, &fanout_list, list) {
1329 if (f->id == id &&
1330 read_pnet(&f->net) == sock_net(sk)) {
1331 match = f;
1332 break;
1333 }
1334 }
1335 err = -EINVAL;
1336 if (match && match->flags != flags)
1337 goto out;
1338 if (!match) {
1339 err = -ENOMEM;
1340 match = kzalloc(sizeof(*match), GFP_KERNEL);
1341 if (!match)
1342 goto out;
1343 write_pnet(&match->net, sock_net(sk));
1344 match->id = id;
1345 match->type = type;
1346 match->flags = flags;
1347 atomic_set(&match->rr_cur, 0);
1348 INIT_LIST_HEAD(&match->list);
1349 spin_lock_init(&match->lock);
1350 atomic_set(&match->sk_ref, 0);
1351 match->prot_hook.type = po->prot_hook.type;
1352 match->prot_hook.dev = po->prot_hook.dev;
1353 match->prot_hook.func = packet_rcv_fanout;
1354 match->prot_hook.af_packet_priv = match;
1355 match->prot_hook.id_match = match_fanout_group;
1356 dev_add_pack(&match->prot_hook);
1357 list_add(&match->list, &fanout_list);
1358 }
1359 err = -EINVAL;
1360 if (match->type == type &&
1361 match->prot_hook.type == po->prot_hook.type &&
1362 match->prot_hook.dev == po->prot_hook.dev) {
1363 err = -ENOSPC;
1364 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1365 __dev_remove_pack(&po->prot_hook);
1366 po->fanout = match;
1367 atomic_inc(&match->sk_ref);
1368 __fanout_link(sk, po);
1369 err = 0;
1370 }
1371 }
1372 out:
1373 mutex_unlock(&fanout_mutex);
1374 return err;
1375 }
1376
1377 static void fanout_release(struct sock *sk)
1378 {
1379 struct packet_sock *po = pkt_sk(sk);
1380 struct packet_fanout *f;
1381
1382 f = po->fanout;
1383 if (!f)
1384 return;
1385
1386 mutex_lock(&fanout_mutex);
1387 po->fanout = NULL;
1388
1389 if (atomic_dec_and_test(&f->sk_ref)) {
1390 list_del(&f->list);
1391 dev_remove_pack(&f->prot_hook);
1392 kfree(f);
1393 }
1394 mutex_unlock(&fanout_mutex);
1395 }
1396
1397 static const struct proto_ops packet_ops;
1398
1399 static const struct proto_ops packet_ops_spkt;
1400
1401 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1402 struct packet_type *pt, struct net_device *orig_dev)
1403 {
1404 struct sock *sk;
1405 struct sockaddr_pkt *spkt;
1406
1407 /*
1408 * When we registered the protocol we saved the socket in the data
1409 * field for just this event.
1410 */
1411
1412 sk = pt->af_packet_priv;
1413
1414 /*
1415 * Yank back the headers [hope the device set this
1416 * right or kerboom...]
1417 *
1418 * Incoming packets have ll header pulled,
1419 * push it back.
1420 *
1421 * For outgoing ones skb->data == skb_mac_header(skb)
1422 * so that this procedure is noop.
1423 */
1424
1425 if (skb->pkt_type == PACKET_LOOPBACK)
1426 goto out;
1427
1428 if (!net_eq(dev_net(dev), sock_net(sk)))
1429 goto out;
1430
1431 skb = skb_share_check(skb, GFP_ATOMIC);
1432 if (skb == NULL)
1433 goto oom;
1434
1435 /* drop any routing info */
1436 skb_dst_drop(skb);
1437
1438 /* drop conntrack reference */
1439 nf_reset(skb);
1440
1441 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1442
1443 skb_push(skb, skb->data - skb_mac_header(skb));
1444
1445 /*
1446 * The SOCK_PACKET socket receives _all_ frames.
1447 */
1448
1449 spkt->spkt_family = dev->type;
1450 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1451 spkt->spkt_protocol = skb->protocol;
1452
1453 /*
1454 * Charge the memory to the socket. This is done specifically
1455 * to prevent sockets using all the memory up.
1456 */
1457
1458 if (sock_queue_rcv_skb(sk, skb) == 0)
1459 return 0;
1460
1461 out:
1462 kfree_skb(skb);
1463 oom:
1464 return 0;
1465 }
1466
1467
1468 /*
1469 * Output a raw packet to a device layer. This bypasses all the other
1470 * protocol layers and you must therefore supply it with a complete frame
1471 */
1472
1473 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1474 struct msghdr *msg, size_t len)
1475 {
1476 struct sock *sk = sock->sk;
1477 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1478 struct sk_buff *skb = NULL;
1479 struct net_device *dev;
1480 __be16 proto = 0;
1481 int err;
1482 int extra_len = 0;
1483
1484 /*
1485 * Get and verify the address.
1486 */
1487
1488 if (saddr) {
1489 if (msg->msg_namelen < sizeof(struct sockaddr))
1490 return -EINVAL;
1491 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1492 proto = saddr->spkt_protocol;
1493 } else
1494 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1495
1496 /*
1497 * Find the device first to size check it
1498 */
1499
1500 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1501 retry:
1502 rcu_read_lock();
1503 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1504 err = -ENODEV;
1505 if (dev == NULL)
1506 goto out_unlock;
1507
1508 err = -ENETDOWN;
1509 if (!(dev->flags & IFF_UP))
1510 goto out_unlock;
1511
1512 /*
1513 * You may not queue a frame bigger than the mtu. This is the lowest level
1514 * raw protocol and you must do your own fragmentation at this level.
1515 */
1516
1517 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1518 if (!netif_supports_nofcs(dev)) {
1519 err = -EPROTONOSUPPORT;
1520 goto out_unlock;
1521 }
1522 extra_len = 4; /* We're doing our own CRC */
1523 }
1524
1525 err = -EMSGSIZE;
1526 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1527 goto out_unlock;
1528
1529 if (!skb) {
1530 size_t reserved = LL_RESERVED_SPACE(dev);
1531 int tlen = dev->needed_tailroom;
1532 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1533
1534 rcu_read_unlock();
1535 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1536 if (skb == NULL)
1537 return -ENOBUFS;
1538 /* FIXME: Save some space for broken drivers that write a hard
1539 * header at transmission time by themselves. PPP is the notable
1540 * one here. This should really be fixed at the driver level.
1541 */
1542 skb_reserve(skb, reserved);
1543 skb_reset_network_header(skb);
1544
1545 /* Try to align data part correctly */
1546 if (hhlen) {
1547 skb->data -= hhlen;
1548 skb->tail -= hhlen;
1549 if (len < hhlen)
1550 skb_reset_network_header(skb);
1551 }
1552 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1553 if (err)
1554 goto out_free;
1555 goto retry;
1556 }
1557
1558 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1559 /* Earlier code assumed this would be a VLAN pkt,
1560 * double-check this now that we have the actual
1561 * packet in hand.
1562 */
1563 struct ethhdr *ehdr;
1564 skb_reset_mac_header(skb);
1565 ehdr = eth_hdr(skb);
1566 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1567 err = -EMSGSIZE;
1568 goto out_unlock;
1569 }
1570 }
1571
1572 skb->protocol = proto;
1573 skb->dev = dev;
1574 skb->priority = sk->sk_priority;
1575 skb->mark = sk->sk_mark;
1576
1577 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1578
1579 if (unlikely(extra_len == 4))
1580 skb->no_fcs = 1;
1581
1582 skb_probe_transport_header(skb, 0);
1583
1584 dev_queue_xmit(skb);
1585 rcu_read_unlock();
1586 return len;
1587
1588 out_unlock:
1589 rcu_read_unlock();
1590 out_free:
1591 kfree_skb(skb);
1592 return err;
1593 }
1594
1595 static unsigned int run_filter(const struct sk_buff *skb,
1596 const struct sock *sk,
1597 unsigned int res)
1598 {
1599 struct sk_filter *filter;
1600
1601 rcu_read_lock();
1602 filter = rcu_dereference(sk->sk_filter);
1603 if (filter != NULL)
1604 res = SK_RUN_FILTER(filter, skb);
1605 rcu_read_unlock();
1606
1607 return res;
1608 }
1609
1610 /*
1611 * This function makes lazy skb cloning in hope that most of packets
1612 * are discarded by BPF.
1613 *
1614 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1615 * and skb->cb are mangled. It works because (and until) packets
1616 * falling here are owned by current CPU. Output packets are cloned
1617 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1618 * sequencially, so that if we return skb to original state on exit,
1619 * we will not harm anyone.
1620 */
1621
1622 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1623 struct packet_type *pt, struct net_device *orig_dev)
1624 {
1625 struct sock *sk;
1626 struct sockaddr_ll *sll;
1627 struct packet_sock *po;
1628 u8 *skb_head = skb->data;
1629 int skb_len = skb->len;
1630 unsigned int snaplen, res;
1631
1632 if (skb->pkt_type == PACKET_LOOPBACK)
1633 goto drop;
1634
1635 sk = pt->af_packet_priv;
1636 po = pkt_sk(sk);
1637
1638 if (!net_eq(dev_net(dev), sock_net(sk)))
1639 goto drop;
1640
1641 skb->dev = dev;
1642
1643 if (dev->header_ops) {
1644 /* The device has an explicit notion of ll header,
1645 * exported to higher levels.
1646 *
1647 * Otherwise, the device hides details of its frame
1648 * structure, so that corresponding packet head is
1649 * never delivered to user.
1650 */
1651 if (sk->sk_type != SOCK_DGRAM)
1652 skb_push(skb, skb->data - skb_mac_header(skb));
1653 else if (skb->pkt_type == PACKET_OUTGOING) {
1654 /* Special case: outgoing packets have ll header at head */
1655 skb_pull(skb, skb_network_offset(skb));
1656 }
1657 }
1658
1659 snaplen = skb->len;
1660
1661 res = run_filter(skb, sk, snaplen);
1662 if (!res)
1663 goto drop_n_restore;
1664 if (snaplen > res)
1665 snaplen = res;
1666
1667 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1668 goto drop_n_acct;
1669
1670 if (skb_shared(skb)) {
1671 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1672 if (nskb == NULL)
1673 goto drop_n_acct;
1674
1675 if (skb_head != skb->data) {
1676 skb->data = skb_head;
1677 skb->len = skb_len;
1678 }
1679 consume_skb(skb);
1680 skb = nskb;
1681 }
1682
1683 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1684 sizeof(skb->cb));
1685
1686 sll = &PACKET_SKB_CB(skb)->sa.ll;
1687 sll->sll_family = AF_PACKET;
1688 sll->sll_hatype = dev->type;
1689 sll->sll_protocol = skb->protocol;
1690 sll->sll_pkttype = skb->pkt_type;
1691 if (unlikely(po->origdev))
1692 sll->sll_ifindex = orig_dev->ifindex;
1693 else
1694 sll->sll_ifindex = dev->ifindex;
1695
1696 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1697
1698 PACKET_SKB_CB(skb)->origlen = skb->len;
1699
1700 if (pskb_trim(skb, snaplen))
1701 goto drop_n_acct;
1702
1703 skb_set_owner_r(skb, sk);
1704 skb->dev = NULL;
1705 skb_dst_drop(skb);
1706
1707 /* drop conntrack reference */
1708 nf_reset(skb);
1709
1710 spin_lock(&sk->sk_receive_queue.lock);
1711 po->stats.stats1.tp_packets++;
1712 skb->dropcount = atomic_read(&sk->sk_drops);
1713 __skb_queue_tail(&sk->sk_receive_queue, skb);
1714 spin_unlock(&sk->sk_receive_queue.lock);
1715 sk->sk_data_ready(sk, skb->len);
1716 return 0;
1717
1718 drop_n_acct:
1719 spin_lock(&sk->sk_receive_queue.lock);
1720 po->stats.stats1.tp_drops++;
1721 atomic_inc(&sk->sk_drops);
1722 spin_unlock(&sk->sk_receive_queue.lock);
1723
1724 drop_n_restore:
1725 if (skb_head != skb->data && skb_shared(skb)) {
1726 skb->data = skb_head;
1727 skb->len = skb_len;
1728 }
1729 drop:
1730 consume_skb(skb);
1731 return 0;
1732 }
1733
1734 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1735 struct packet_type *pt, struct net_device *orig_dev)
1736 {
1737 struct sock *sk;
1738 struct packet_sock *po;
1739 struct sockaddr_ll *sll;
1740 union tpacket_uhdr h;
1741 u8 *skb_head = skb->data;
1742 int skb_len = skb->len;
1743 unsigned int snaplen, res;
1744 unsigned long status = TP_STATUS_USER;
1745 unsigned short macoff, netoff, hdrlen;
1746 struct sk_buff *copy_skb = NULL;
1747 struct timespec ts;
1748 __u32 ts_status;
1749
1750 if (skb->pkt_type == PACKET_LOOPBACK)
1751 goto drop;
1752
1753 sk = pt->af_packet_priv;
1754 po = pkt_sk(sk);
1755
1756 if (!net_eq(dev_net(dev), sock_net(sk)))
1757 goto drop;
1758
1759 if (dev->header_ops) {
1760 if (sk->sk_type != SOCK_DGRAM)
1761 skb_push(skb, skb->data - skb_mac_header(skb));
1762 else if (skb->pkt_type == PACKET_OUTGOING) {
1763 /* Special case: outgoing packets have ll header at head */
1764 skb_pull(skb, skb_network_offset(skb));
1765 }
1766 }
1767
1768 if (skb->ip_summed == CHECKSUM_PARTIAL)
1769 status |= TP_STATUS_CSUMNOTREADY;
1770
1771 snaplen = skb->len;
1772
1773 res = run_filter(skb, sk, snaplen);
1774 if (!res)
1775 goto drop_n_restore;
1776 if (snaplen > res)
1777 snaplen = res;
1778
1779 if (sk->sk_type == SOCK_DGRAM) {
1780 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1781 po->tp_reserve;
1782 } else {
1783 unsigned int maclen = skb_network_offset(skb);
1784 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1785 (maclen < 16 ? 16 : maclen)) +
1786 po->tp_reserve;
1787 macoff = netoff - maclen;
1788 }
1789 if (po->tp_version <= TPACKET_V2) {
1790 if (macoff + snaplen > po->rx_ring.frame_size) {
1791 if (po->copy_thresh &&
1792 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1793 if (skb_shared(skb)) {
1794 copy_skb = skb_clone(skb, GFP_ATOMIC);
1795 } else {
1796 copy_skb = skb_get(skb);
1797 skb_head = skb->data;
1798 }
1799 if (copy_skb)
1800 skb_set_owner_r(copy_skb, sk);
1801 }
1802 snaplen = po->rx_ring.frame_size - macoff;
1803 if ((int)snaplen < 0)
1804 snaplen = 0;
1805 }
1806 }
1807 spin_lock(&sk->sk_receive_queue.lock);
1808 h.raw = packet_current_rx_frame(po, skb,
1809 TP_STATUS_KERNEL, (macoff+snaplen));
1810 if (!h.raw)
1811 goto ring_is_full;
1812 if (po->tp_version <= TPACKET_V2) {
1813 packet_increment_rx_head(po, &po->rx_ring);
1814 /*
1815 * LOSING will be reported till you read the stats,
1816 * because it's COR - Clear On Read.
1817 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1818 * at packet level.
1819 */
1820 if (po->stats.stats1.tp_drops)
1821 status |= TP_STATUS_LOSING;
1822 }
1823 po->stats.stats1.tp_packets++;
1824 if (copy_skb) {
1825 status |= TP_STATUS_COPY;
1826 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1827 }
1828 spin_unlock(&sk->sk_receive_queue.lock);
1829
1830 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1831
1832 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1833 getnstimeofday(&ts);
1834
1835 status |= ts_status;
1836
1837 switch (po->tp_version) {
1838 case TPACKET_V1:
1839 h.h1->tp_len = skb->len;
1840 h.h1->tp_snaplen = snaplen;
1841 h.h1->tp_mac = macoff;
1842 h.h1->tp_net = netoff;
1843 h.h1->tp_sec = ts.tv_sec;
1844 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
1845 hdrlen = sizeof(*h.h1);
1846 break;
1847 case TPACKET_V2:
1848 h.h2->tp_len = skb->len;
1849 h.h2->tp_snaplen = snaplen;
1850 h.h2->tp_mac = macoff;
1851 h.h2->tp_net = netoff;
1852 h.h2->tp_sec = ts.tv_sec;
1853 h.h2->tp_nsec = ts.tv_nsec;
1854 if (vlan_tx_tag_present(skb)) {
1855 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1856 status |= TP_STATUS_VLAN_VALID;
1857 } else {
1858 h.h2->tp_vlan_tci = 0;
1859 }
1860 h.h2->tp_padding = 0;
1861 hdrlen = sizeof(*h.h2);
1862 break;
1863 case TPACKET_V3:
1864 /* tp_nxt_offset,vlan are already populated above.
1865 * So DONT clear those fields here
1866 */
1867 h.h3->tp_status |= status;
1868 h.h3->tp_len = skb->len;
1869 h.h3->tp_snaplen = snaplen;
1870 h.h3->tp_mac = macoff;
1871 h.h3->tp_net = netoff;
1872 h.h3->tp_sec = ts.tv_sec;
1873 h.h3->tp_nsec = ts.tv_nsec;
1874 hdrlen = sizeof(*h.h3);
1875 break;
1876 default:
1877 BUG();
1878 }
1879
1880 sll = h.raw + TPACKET_ALIGN(hdrlen);
1881 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1882 sll->sll_family = AF_PACKET;
1883 sll->sll_hatype = dev->type;
1884 sll->sll_protocol = skb->protocol;
1885 sll->sll_pkttype = skb->pkt_type;
1886 if (unlikely(po->origdev))
1887 sll->sll_ifindex = orig_dev->ifindex;
1888 else
1889 sll->sll_ifindex = dev->ifindex;
1890
1891 smp_mb();
1892 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1893 {
1894 u8 *start, *end;
1895
1896 if (po->tp_version <= TPACKET_V2) {
1897 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1898 + macoff + snaplen);
1899 for (start = h.raw; start < end; start += PAGE_SIZE)
1900 flush_dcache_page(pgv_to_page(start));
1901 }
1902 smp_wmb();
1903 }
1904 #endif
1905 if (po->tp_version <= TPACKET_V2)
1906 __packet_set_status(po, h.raw, status);
1907 else
1908 prb_clear_blk_fill_status(&po->rx_ring);
1909
1910 sk->sk_data_ready(sk, 0);
1911
1912 drop_n_restore:
1913 if (skb_head != skb->data && skb_shared(skb)) {
1914 skb->data = skb_head;
1915 skb->len = skb_len;
1916 }
1917 drop:
1918 kfree_skb(skb);
1919 return 0;
1920
1921 ring_is_full:
1922 po->stats.stats1.tp_drops++;
1923 spin_unlock(&sk->sk_receive_queue.lock);
1924
1925 sk->sk_data_ready(sk, 0);
1926 kfree_skb(copy_skb);
1927 goto drop_n_restore;
1928 }
1929
1930 static void tpacket_destruct_skb(struct sk_buff *skb)
1931 {
1932 struct packet_sock *po = pkt_sk(skb->sk);
1933 void *ph;
1934
1935 if (likely(po->tx_ring.pg_vec)) {
1936 __u32 ts;
1937
1938 ph = skb_shinfo(skb)->destructor_arg;
1939 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1940 atomic_dec(&po->tx_ring.pending);
1941
1942 ts = __packet_set_timestamp(po, ph, skb);
1943 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
1944 }
1945
1946 sock_wfree(skb);
1947 }
1948
1949 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1950 void *frame, struct net_device *dev, int size_max,
1951 __be16 proto, unsigned char *addr, int hlen)
1952 {
1953 union tpacket_uhdr ph;
1954 int to_write, offset, len, tp_len, nr_frags, len_max;
1955 struct socket *sock = po->sk.sk_socket;
1956 struct page *page;
1957 void *data;
1958 int err;
1959
1960 ph.raw = frame;
1961
1962 skb->protocol = proto;
1963 skb->dev = dev;
1964 skb->priority = po->sk.sk_priority;
1965 skb->mark = po->sk.sk_mark;
1966 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
1967 skb_shinfo(skb)->destructor_arg = ph.raw;
1968
1969 switch (po->tp_version) {
1970 case TPACKET_V2:
1971 tp_len = ph.h2->tp_len;
1972 break;
1973 default:
1974 tp_len = ph.h1->tp_len;
1975 break;
1976 }
1977 if (unlikely(tp_len > size_max)) {
1978 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1979 return -EMSGSIZE;
1980 }
1981
1982 skb_reserve(skb, hlen);
1983 skb_reset_network_header(skb);
1984 skb_probe_transport_header(skb, 0);
1985
1986 if (po->tp_tx_has_off) {
1987 int off_min, off_max, off;
1988 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
1989 off_max = po->tx_ring.frame_size - tp_len;
1990 if (sock->type == SOCK_DGRAM) {
1991 switch (po->tp_version) {
1992 case TPACKET_V2:
1993 off = ph.h2->tp_net;
1994 break;
1995 default:
1996 off = ph.h1->tp_net;
1997 break;
1998 }
1999 } else {
2000 switch (po->tp_version) {
2001 case TPACKET_V2:
2002 off = ph.h2->tp_mac;
2003 break;
2004 default:
2005 off = ph.h1->tp_mac;
2006 break;
2007 }
2008 }
2009 if (unlikely((off < off_min) || (off_max < off)))
2010 return -EINVAL;
2011 data = ph.raw + off;
2012 } else {
2013 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2014 }
2015 to_write = tp_len;
2016
2017 if (sock->type == SOCK_DGRAM) {
2018 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2019 NULL, tp_len);
2020 if (unlikely(err < 0))
2021 return -EINVAL;
2022 } else if (dev->hard_header_len) {
2023 /* net device doesn't like empty head */
2024 if (unlikely(tp_len <= dev->hard_header_len)) {
2025 pr_err("packet size is too short (%d < %d)\n",
2026 tp_len, dev->hard_header_len);
2027 return -EINVAL;
2028 }
2029
2030 skb_push(skb, dev->hard_header_len);
2031 err = skb_store_bits(skb, 0, data,
2032 dev->hard_header_len);
2033 if (unlikely(err))
2034 return err;
2035
2036 data += dev->hard_header_len;
2037 to_write -= dev->hard_header_len;
2038 }
2039
2040 offset = offset_in_page(data);
2041 len_max = PAGE_SIZE - offset;
2042 len = ((to_write > len_max) ? len_max : to_write);
2043
2044 skb->data_len = to_write;
2045 skb->len += to_write;
2046 skb->truesize += to_write;
2047 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2048
2049 while (likely(to_write)) {
2050 nr_frags = skb_shinfo(skb)->nr_frags;
2051
2052 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2053 pr_err("Packet exceed the number of skb frags(%lu)\n",
2054 MAX_SKB_FRAGS);
2055 return -EFAULT;
2056 }
2057
2058 page = pgv_to_page(data);
2059 data += len;
2060 flush_dcache_page(page);
2061 get_page(page);
2062 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2063 to_write -= len;
2064 offset = 0;
2065 len_max = PAGE_SIZE;
2066 len = ((to_write > len_max) ? len_max : to_write);
2067 }
2068
2069 return tp_len;
2070 }
2071
2072 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2073 {
2074 struct sk_buff *skb;
2075 struct net_device *dev;
2076 __be16 proto;
2077 int err, reserve = 0;
2078 void *ph;
2079 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2080 int tp_len, size_max;
2081 unsigned char *addr;
2082 int len_sum = 0;
2083 int status = TP_STATUS_AVAILABLE;
2084 int hlen, tlen;
2085
2086 mutex_lock(&po->pg_vec_lock);
2087
2088 if (likely(saddr == NULL)) {
2089 dev = packet_cached_dev_get(po);
2090 proto = po->num;
2091 addr = NULL;
2092 } else {
2093 err = -EINVAL;
2094 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2095 goto out;
2096 if (msg->msg_namelen < (saddr->sll_halen
2097 + offsetof(struct sockaddr_ll,
2098 sll_addr)))
2099 goto out;
2100 proto = saddr->sll_protocol;
2101 addr = saddr->sll_addr;
2102 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2103 }
2104
2105 err = -ENXIO;
2106 if (unlikely(dev == NULL))
2107 goto out;
2108 err = -ENETDOWN;
2109 if (unlikely(!(dev->flags & IFF_UP)))
2110 goto out_put;
2111
2112 reserve = dev->hard_header_len;
2113
2114 size_max = po->tx_ring.frame_size
2115 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2116
2117 if (size_max > dev->mtu + reserve)
2118 size_max = dev->mtu + reserve;
2119
2120 do {
2121 ph = packet_current_frame(po, &po->tx_ring,
2122 TP_STATUS_SEND_REQUEST);
2123
2124 if (unlikely(ph == NULL)) {
2125 schedule();
2126 continue;
2127 }
2128
2129 status = TP_STATUS_SEND_REQUEST;
2130 hlen = LL_RESERVED_SPACE(dev);
2131 tlen = dev->needed_tailroom;
2132 skb = sock_alloc_send_skb(&po->sk,
2133 hlen + tlen + sizeof(struct sockaddr_ll),
2134 0, &err);
2135
2136 if (unlikely(skb == NULL))
2137 goto out_status;
2138
2139 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2140 addr, hlen);
2141
2142 if (unlikely(tp_len < 0)) {
2143 if (po->tp_loss) {
2144 __packet_set_status(po, ph,
2145 TP_STATUS_AVAILABLE);
2146 packet_increment_head(&po->tx_ring);
2147 kfree_skb(skb);
2148 continue;
2149 } else {
2150 status = TP_STATUS_WRONG_FORMAT;
2151 err = tp_len;
2152 goto out_status;
2153 }
2154 }
2155
2156 skb->destructor = tpacket_destruct_skb;
2157 __packet_set_status(po, ph, TP_STATUS_SENDING);
2158 atomic_inc(&po->tx_ring.pending);
2159
2160 status = TP_STATUS_SEND_REQUEST;
2161 err = dev_queue_xmit(skb);
2162 if (unlikely(err > 0)) {
2163 err = net_xmit_errno(err);
2164 if (err && __packet_get_status(po, ph) ==
2165 TP_STATUS_AVAILABLE) {
2166 /* skb was destructed already */
2167 skb = NULL;
2168 goto out_status;
2169 }
2170 /*
2171 * skb was dropped but not destructed yet;
2172 * let's treat it like congestion or err < 0
2173 */
2174 err = 0;
2175 }
2176 packet_increment_head(&po->tx_ring);
2177 len_sum += tp_len;
2178 } while (likely((ph != NULL) ||
2179 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2180 (atomic_read(&po->tx_ring.pending))))
2181 );
2182
2183 err = len_sum;
2184 goto out_put;
2185
2186 out_status:
2187 __packet_set_status(po, ph, status);
2188 kfree_skb(skb);
2189 out_put:
2190 dev_put(dev);
2191 out:
2192 mutex_unlock(&po->pg_vec_lock);
2193 return err;
2194 }
2195
2196 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2197 size_t reserve, size_t len,
2198 size_t linear, int noblock,
2199 int *err)
2200 {
2201 struct sk_buff *skb;
2202
2203 /* Under a page? Don't bother with paged skb. */
2204 if (prepad + len < PAGE_SIZE || !linear)
2205 linear = len;
2206
2207 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2208 err);
2209 if (!skb)
2210 return NULL;
2211
2212 skb_reserve(skb, reserve);
2213 skb_put(skb, linear);
2214 skb->data_len = len - linear;
2215 skb->len += len - linear;
2216
2217 return skb;
2218 }
2219
2220 static int packet_snd(struct socket *sock,
2221 struct msghdr *msg, size_t len)
2222 {
2223 struct sock *sk = sock->sk;
2224 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2225 struct sk_buff *skb;
2226 struct net_device *dev;
2227 __be16 proto;
2228 unsigned char *addr;
2229 int err, reserve = 0;
2230 struct virtio_net_hdr vnet_hdr = { 0 };
2231 int offset = 0;
2232 int vnet_hdr_len;
2233 struct packet_sock *po = pkt_sk(sk);
2234 unsigned short gso_type = 0;
2235 int hlen, tlen;
2236 int extra_len = 0;
2237
2238 /*
2239 * Get and verify the address.
2240 */
2241
2242 if (likely(saddr == NULL)) {
2243 dev = packet_cached_dev_get(po);
2244 proto = po->num;
2245 addr = NULL;
2246 } else {
2247 err = -EINVAL;
2248 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2249 goto out;
2250 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2251 goto out;
2252 proto = saddr->sll_protocol;
2253 addr = saddr->sll_addr;
2254 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2255 }
2256
2257 err = -ENXIO;
2258 if (unlikely(dev == NULL))
2259 goto out_unlock;
2260 err = -ENETDOWN;
2261 if (unlikely(!(dev->flags & IFF_UP)))
2262 goto out_unlock;
2263
2264 if (sock->type == SOCK_RAW)
2265 reserve = dev->hard_header_len;
2266 if (po->has_vnet_hdr) {
2267 vnet_hdr_len = sizeof(vnet_hdr);
2268
2269 err = -EINVAL;
2270 if (len < vnet_hdr_len)
2271 goto out_unlock;
2272
2273 len -= vnet_hdr_len;
2274
2275 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2276 vnet_hdr_len);
2277 if (err < 0)
2278 goto out_unlock;
2279
2280 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2281 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2282 vnet_hdr.hdr_len))
2283 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2284 vnet_hdr.csum_offset + 2;
2285
2286 err = -EINVAL;
2287 if (vnet_hdr.hdr_len > len)
2288 goto out_unlock;
2289
2290 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2291 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2292 case VIRTIO_NET_HDR_GSO_TCPV4:
2293 gso_type = SKB_GSO_TCPV4;
2294 break;
2295 case VIRTIO_NET_HDR_GSO_TCPV6:
2296 gso_type = SKB_GSO_TCPV6;
2297 break;
2298 case VIRTIO_NET_HDR_GSO_UDP:
2299 gso_type = SKB_GSO_UDP;
2300 break;
2301 default:
2302 goto out_unlock;
2303 }
2304
2305 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2306 gso_type |= SKB_GSO_TCP_ECN;
2307
2308 if (vnet_hdr.gso_size == 0)
2309 goto out_unlock;
2310
2311 }
2312 }
2313
2314 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2315 if (!netif_supports_nofcs(dev)) {
2316 err = -EPROTONOSUPPORT;
2317 goto out_unlock;
2318 }
2319 extra_len = 4; /* We're doing our own CRC */
2320 }
2321
2322 err = -EMSGSIZE;
2323 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2324 goto out_unlock;
2325
2326 err = -ENOBUFS;
2327 hlen = LL_RESERVED_SPACE(dev);
2328 tlen = dev->needed_tailroom;
2329 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2330 msg->msg_flags & MSG_DONTWAIT, &err);
2331 if (skb == NULL)
2332 goto out_unlock;
2333
2334 skb_set_network_header(skb, reserve);
2335
2336 err = -EINVAL;
2337 if (sock->type == SOCK_DGRAM &&
2338 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2339 goto out_free;
2340
2341 /* Returns -EFAULT on error */
2342 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2343 if (err)
2344 goto out_free;
2345
2346 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2347
2348 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2349 /* Earlier code assumed this would be a VLAN pkt,
2350 * double-check this now that we have the actual
2351 * packet in hand.
2352 */
2353 struct ethhdr *ehdr;
2354 skb_reset_mac_header(skb);
2355 ehdr = eth_hdr(skb);
2356 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2357 err = -EMSGSIZE;
2358 goto out_free;
2359 }
2360 }
2361
2362 skb->protocol = proto;
2363 skb->dev = dev;
2364 skb->priority = sk->sk_priority;
2365 skb->mark = sk->sk_mark;
2366
2367 if (po->has_vnet_hdr) {
2368 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2369 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2370 vnet_hdr.csum_offset)) {
2371 err = -EINVAL;
2372 goto out_free;
2373 }
2374 }
2375
2376 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2377 skb_shinfo(skb)->gso_type = gso_type;
2378
2379 /* Header must be checked, and gso_segs computed. */
2380 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2381 skb_shinfo(skb)->gso_segs = 0;
2382
2383 len += vnet_hdr_len;
2384 }
2385
2386 skb_probe_transport_header(skb, reserve);
2387
2388 if (unlikely(extra_len == 4))
2389 skb->no_fcs = 1;
2390
2391 /*
2392 * Now send it
2393 */
2394
2395 err = dev_queue_xmit(skb);
2396 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2397 goto out_unlock;
2398
2399 dev_put(dev);
2400
2401 return len;
2402
2403 out_free:
2404 kfree_skb(skb);
2405 out_unlock:
2406 if (dev)
2407 dev_put(dev);
2408 out:
2409 return err;
2410 }
2411
2412 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2413 struct msghdr *msg, size_t len)
2414 {
2415 struct sock *sk = sock->sk;
2416 struct packet_sock *po = pkt_sk(sk);
2417 if (po->tx_ring.pg_vec)
2418 return tpacket_snd(po, msg);
2419 else
2420 return packet_snd(sock, msg, len);
2421 }
2422
2423 /*
2424 * Close a PACKET socket. This is fairly simple. We immediately go
2425 * to 'closed' state and remove our protocol entry in the device list.
2426 */
2427
2428 static int packet_release(struct socket *sock)
2429 {
2430 struct sock *sk = sock->sk;
2431 struct packet_sock *po;
2432 struct net *net;
2433 union tpacket_req_u req_u;
2434
2435 if (!sk)
2436 return 0;
2437
2438 net = sock_net(sk);
2439 po = pkt_sk(sk);
2440
2441 mutex_lock(&net->packet.sklist_lock);
2442 sk_del_node_init_rcu(sk);
2443 mutex_unlock(&net->packet.sklist_lock);
2444
2445 preempt_disable();
2446 sock_prot_inuse_add(net, sk->sk_prot, -1);
2447 preempt_enable();
2448
2449 spin_lock(&po->bind_lock);
2450 unregister_prot_hook(sk, false);
2451 packet_cached_dev_reset(po);
2452
2453 if (po->prot_hook.dev) {
2454 dev_put(po->prot_hook.dev);
2455 po->prot_hook.dev = NULL;
2456 }
2457 spin_unlock(&po->bind_lock);
2458
2459 packet_flush_mclist(sk);
2460
2461 if (po->rx_ring.pg_vec) {
2462 memset(&req_u, 0, sizeof(req_u));
2463 packet_set_ring(sk, &req_u, 1, 0);
2464 }
2465
2466 if (po->tx_ring.pg_vec) {
2467 memset(&req_u, 0, sizeof(req_u));
2468 packet_set_ring(sk, &req_u, 1, 1);
2469 }
2470
2471 fanout_release(sk);
2472
2473 synchronize_net();
2474 /*
2475 * Now the socket is dead. No more input will appear.
2476 */
2477 sock_orphan(sk);
2478 sock->sk = NULL;
2479
2480 /* Purge queues */
2481
2482 skb_queue_purge(&sk->sk_receive_queue);
2483 sk_refcnt_debug_release(sk);
2484
2485 sock_put(sk);
2486 return 0;
2487 }
2488
2489 /*
2490 * Attach a packet hook.
2491 */
2492
2493 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2494 {
2495 struct packet_sock *po = pkt_sk(sk);
2496
2497 if (po->fanout) {
2498 if (dev)
2499 dev_put(dev);
2500
2501 return -EINVAL;
2502 }
2503
2504 lock_sock(sk);
2505
2506 spin_lock(&po->bind_lock);
2507 unregister_prot_hook(sk, true);
2508
2509 po->num = protocol;
2510 po->prot_hook.type = protocol;
2511 if (po->prot_hook.dev)
2512 dev_put(po->prot_hook.dev);
2513
2514 po->prot_hook.dev = dev;
2515 po->ifindex = dev ? dev->ifindex : 0;
2516
2517 packet_cached_dev_assign(po, dev);
2518
2519 if (protocol == 0)
2520 goto out_unlock;
2521
2522 if (!dev || (dev->flags & IFF_UP)) {
2523 register_prot_hook(sk);
2524 } else {
2525 sk->sk_err = ENETDOWN;
2526 if (!sock_flag(sk, SOCK_DEAD))
2527 sk->sk_error_report(sk);
2528 }
2529
2530 out_unlock:
2531 spin_unlock(&po->bind_lock);
2532 release_sock(sk);
2533 return 0;
2534 }
2535
2536 /*
2537 * Bind a packet socket to a device
2538 */
2539
2540 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2541 int addr_len)
2542 {
2543 struct sock *sk = sock->sk;
2544 char name[15];
2545 struct net_device *dev;
2546 int err = -ENODEV;
2547
2548 /*
2549 * Check legality
2550 */
2551
2552 if (addr_len != sizeof(struct sockaddr))
2553 return -EINVAL;
2554 strlcpy(name, uaddr->sa_data, sizeof(name));
2555
2556 dev = dev_get_by_name(sock_net(sk), name);
2557 if (dev)
2558 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2559 return err;
2560 }
2561
2562 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2563 {
2564 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2565 struct sock *sk = sock->sk;
2566 struct net_device *dev = NULL;
2567 int err;
2568
2569
2570 /*
2571 * Check legality
2572 */
2573
2574 if (addr_len < sizeof(struct sockaddr_ll))
2575 return -EINVAL;
2576 if (sll->sll_family != AF_PACKET)
2577 return -EINVAL;
2578
2579 if (sll->sll_ifindex) {
2580 err = -ENODEV;
2581 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2582 if (dev == NULL)
2583 goto out;
2584 }
2585 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2586
2587 out:
2588 return err;
2589 }
2590
2591 static struct proto packet_proto = {
2592 .name = "PACKET",
2593 .owner = THIS_MODULE,
2594 .obj_size = sizeof(struct packet_sock),
2595 };
2596
2597 /*
2598 * Create a packet of type SOCK_PACKET.
2599 */
2600
2601 static int packet_create(struct net *net, struct socket *sock, int protocol,
2602 int kern)
2603 {
2604 struct sock *sk;
2605 struct packet_sock *po;
2606 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2607 int err;
2608
2609 if (!ns_capable(net->user_ns, CAP_NET_RAW))
2610 return -EPERM;
2611 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2612 sock->type != SOCK_PACKET)
2613 return -ESOCKTNOSUPPORT;
2614
2615 sock->state = SS_UNCONNECTED;
2616
2617 err = -ENOBUFS;
2618 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2619 if (sk == NULL)
2620 goto out;
2621
2622 sock->ops = &packet_ops;
2623 if (sock->type == SOCK_PACKET)
2624 sock->ops = &packet_ops_spkt;
2625
2626 sock_init_data(sock, sk);
2627
2628 po = pkt_sk(sk);
2629 sk->sk_family = PF_PACKET;
2630 po->num = proto;
2631
2632 packet_cached_dev_reset(po);
2633
2634 sk->sk_destruct = packet_sock_destruct;
2635 sk_refcnt_debug_inc(sk);
2636
2637 /*
2638 * Attach a protocol block
2639 */
2640
2641 spin_lock_init(&po->bind_lock);
2642 mutex_init(&po->pg_vec_lock);
2643 po->prot_hook.func = packet_rcv;
2644
2645 if (sock->type == SOCK_PACKET)
2646 po->prot_hook.func = packet_rcv_spkt;
2647
2648 po->prot_hook.af_packet_priv = sk;
2649
2650 if (proto) {
2651 po->prot_hook.type = proto;
2652 register_prot_hook(sk);
2653 }
2654
2655 mutex_lock(&net->packet.sklist_lock);
2656 sk_add_node_rcu(sk, &net->packet.sklist);
2657 mutex_unlock(&net->packet.sklist_lock);
2658
2659 preempt_disable();
2660 sock_prot_inuse_add(net, &packet_proto, 1);
2661 preempt_enable();
2662
2663 return 0;
2664 out:
2665 return err;
2666 }
2667
2668 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2669 {
2670 struct sock_exterr_skb *serr;
2671 struct sk_buff *skb, *skb2;
2672 int copied, err;
2673
2674 err = -EAGAIN;
2675 skb = skb_dequeue(&sk->sk_error_queue);
2676 if (skb == NULL)
2677 goto out;
2678
2679 copied = skb->len;
2680 if (copied > len) {
2681 msg->msg_flags |= MSG_TRUNC;
2682 copied = len;
2683 }
2684 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2685 if (err)
2686 goto out_free_skb;
2687
2688 sock_recv_timestamp(msg, sk, skb);
2689
2690 serr = SKB_EXT_ERR(skb);
2691 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2692 sizeof(serr->ee), &serr->ee);
2693
2694 msg->msg_flags |= MSG_ERRQUEUE;
2695 err = copied;
2696
2697 /* Reset and regenerate socket error */
2698 spin_lock_bh(&sk->sk_error_queue.lock);
2699 sk->sk_err = 0;
2700 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2701 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2702 spin_unlock_bh(&sk->sk_error_queue.lock);
2703 sk->sk_error_report(sk);
2704 } else
2705 spin_unlock_bh(&sk->sk_error_queue.lock);
2706
2707 out_free_skb:
2708 kfree_skb(skb);
2709 out:
2710 return err;
2711 }
2712
2713 /*
2714 * Pull a packet from our receive queue and hand it to the user.
2715 * If necessary we block.
2716 */
2717
2718 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2719 struct msghdr *msg, size_t len, int flags)
2720 {
2721 struct sock *sk = sock->sk;
2722 struct sk_buff *skb;
2723 int copied, err;
2724 int vnet_hdr_len = 0;
2725
2726 err = -EINVAL;
2727 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2728 goto out;
2729
2730 #if 0
2731 /* What error should we return now? EUNATTACH? */
2732 if (pkt_sk(sk)->ifindex < 0)
2733 return -ENODEV;
2734 #endif
2735
2736 if (flags & MSG_ERRQUEUE) {
2737 err = packet_recv_error(sk, msg, len);
2738 goto out;
2739 }
2740
2741 /*
2742 * Call the generic datagram receiver. This handles all sorts
2743 * of horrible races and re-entrancy so we can forget about it
2744 * in the protocol layers.
2745 *
2746 * Now it will return ENETDOWN, if device have just gone down,
2747 * but then it will block.
2748 */
2749
2750 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2751
2752 /*
2753 * An error occurred so return it. Because skb_recv_datagram()
2754 * handles the blocking we don't see and worry about blocking
2755 * retries.
2756 */
2757
2758 if (skb == NULL)
2759 goto out;
2760
2761 if (pkt_sk(sk)->has_vnet_hdr) {
2762 struct virtio_net_hdr vnet_hdr = { 0 };
2763
2764 err = -EINVAL;
2765 vnet_hdr_len = sizeof(vnet_hdr);
2766 if (len < vnet_hdr_len)
2767 goto out_free;
2768
2769 len -= vnet_hdr_len;
2770
2771 if (skb_is_gso(skb)) {
2772 struct skb_shared_info *sinfo = skb_shinfo(skb);
2773
2774 /* This is a hint as to how much should be linear. */
2775 vnet_hdr.hdr_len = skb_headlen(skb);
2776 vnet_hdr.gso_size = sinfo->gso_size;
2777 if (sinfo->gso_type & SKB_GSO_TCPV4)
2778 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2779 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2780 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2781 else if (sinfo->gso_type & SKB_GSO_UDP)
2782 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2783 else if (sinfo->gso_type & SKB_GSO_FCOE)
2784 goto out_free;
2785 else
2786 BUG();
2787 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2788 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2789 } else
2790 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2791
2792 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2793 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2794 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2795 vnet_hdr.csum_offset = skb->csum_offset;
2796 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2797 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2798 } /* else everything is zero */
2799
2800 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2801 vnet_hdr_len);
2802 if (err < 0)
2803 goto out_free;
2804 }
2805
2806 /* You lose any data beyond the buffer you gave. If it worries
2807 * a user program they can ask the device for its MTU
2808 * anyway.
2809 */
2810 copied = skb->len;
2811 if (copied > len) {
2812 copied = len;
2813 msg->msg_flags |= MSG_TRUNC;
2814 }
2815
2816 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2817 if (err)
2818 goto out_free;
2819
2820 sock_recv_ts_and_drops(msg, sk, skb);
2821
2822 if (msg->msg_name) {
2823 /* If the address length field is there to be filled
2824 * in, we fill it in now.
2825 */
2826 if (sock->type == SOCK_PACKET) {
2827 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2828 } else {
2829 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2830 msg->msg_namelen = sll->sll_halen +
2831 offsetof(struct sockaddr_ll, sll_addr);
2832 }
2833 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2834 msg->msg_namelen);
2835 }
2836
2837 if (pkt_sk(sk)->auxdata) {
2838 struct tpacket_auxdata aux;
2839
2840 aux.tp_status = TP_STATUS_USER;
2841 if (skb->ip_summed == CHECKSUM_PARTIAL)
2842 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2843 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2844 aux.tp_snaplen = skb->len;
2845 aux.tp_mac = 0;
2846 aux.tp_net = skb_network_offset(skb);
2847 if (vlan_tx_tag_present(skb)) {
2848 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2849 aux.tp_status |= TP_STATUS_VLAN_VALID;
2850 } else {
2851 aux.tp_vlan_tci = 0;
2852 }
2853 aux.tp_padding = 0;
2854 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2855 }
2856
2857 /*
2858 * Free or return the buffer as appropriate. Again this
2859 * hides all the races and re-entrancy issues from us.
2860 */
2861 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2862
2863 out_free:
2864 skb_free_datagram(sk, skb);
2865 out:
2866 return err;
2867 }
2868
2869 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2870 int *uaddr_len, int peer)
2871 {
2872 struct net_device *dev;
2873 struct sock *sk = sock->sk;
2874
2875 if (peer)
2876 return -EOPNOTSUPP;
2877
2878 uaddr->sa_family = AF_PACKET;
2879 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
2880 rcu_read_lock();
2881 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2882 if (dev)
2883 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
2884 rcu_read_unlock();
2885 *uaddr_len = sizeof(*uaddr);
2886
2887 return 0;
2888 }
2889
2890 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2891 int *uaddr_len, int peer)
2892 {
2893 struct net_device *dev;
2894 struct sock *sk = sock->sk;
2895 struct packet_sock *po = pkt_sk(sk);
2896 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2897
2898 if (peer)
2899 return -EOPNOTSUPP;
2900
2901 sll->sll_family = AF_PACKET;
2902 sll->sll_ifindex = po->ifindex;
2903 sll->sll_protocol = po->num;
2904 sll->sll_pkttype = 0;
2905 rcu_read_lock();
2906 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2907 if (dev) {
2908 sll->sll_hatype = dev->type;
2909 sll->sll_halen = dev->addr_len;
2910 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2911 } else {
2912 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2913 sll->sll_halen = 0;
2914 }
2915 rcu_read_unlock();
2916 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2917
2918 return 0;
2919 }
2920
2921 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2922 int what)
2923 {
2924 switch (i->type) {
2925 case PACKET_MR_MULTICAST:
2926 if (i->alen != dev->addr_len)
2927 return -EINVAL;
2928 if (what > 0)
2929 return dev_mc_add(dev, i->addr);
2930 else
2931 return dev_mc_del(dev, i->addr);
2932 break;
2933 case PACKET_MR_PROMISC:
2934 return dev_set_promiscuity(dev, what);
2935 break;
2936 case PACKET_MR_ALLMULTI:
2937 return dev_set_allmulti(dev, what);
2938 break;
2939 case PACKET_MR_UNICAST:
2940 if (i->alen != dev->addr_len)
2941 return -EINVAL;
2942 if (what > 0)
2943 return dev_uc_add(dev, i->addr);
2944 else
2945 return dev_uc_del(dev, i->addr);
2946 break;
2947 default:
2948 break;
2949 }
2950 return 0;
2951 }
2952
2953 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2954 {
2955 for ( ; i; i = i->next) {
2956 if (i->ifindex == dev->ifindex)
2957 packet_dev_mc(dev, i, what);
2958 }
2959 }
2960
2961 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2962 {
2963 struct packet_sock *po = pkt_sk(sk);
2964 struct packet_mclist *ml, *i;
2965 struct net_device *dev;
2966 int err;
2967
2968 rtnl_lock();
2969
2970 err = -ENODEV;
2971 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2972 if (!dev)
2973 goto done;
2974
2975 err = -EINVAL;
2976 if (mreq->mr_alen > dev->addr_len)
2977 goto done;
2978
2979 err = -ENOBUFS;
2980 i = kmalloc(sizeof(*i), GFP_KERNEL);
2981 if (i == NULL)
2982 goto done;
2983
2984 err = 0;
2985 for (ml = po->mclist; ml; ml = ml->next) {
2986 if (ml->ifindex == mreq->mr_ifindex &&
2987 ml->type == mreq->mr_type &&
2988 ml->alen == mreq->mr_alen &&
2989 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2990 ml->count++;
2991 /* Free the new element ... */
2992 kfree(i);
2993 goto done;
2994 }
2995 }
2996
2997 i->type = mreq->mr_type;
2998 i->ifindex = mreq->mr_ifindex;
2999 i->alen = mreq->mr_alen;
3000 memcpy(i->addr, mreq->mr_address, i->alen);
3001 i->count = 1;
3002 i->next = po->mclist;
3003 po->mclist = i;
3004 err = packet_dev_mc(dev, i, 1);
3005 if (err) {
3006 po->mclist = i->next;
3007 kfree(i);
3008 }
3009
3010 done:
3011 rtnl_unlock();
3012 return err;
3013 }
3014
3015 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3016 {
3017 struct packet_mclist *ml, **mlp;
3018
3019 rtnl_lock();
3020
3021 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3022 if (ml->ifindex == mreq->mr_ifindex &&
3023 ml->type == mreq->mr_type &&
3024 ml->alen == mreq->mr_alen &&
3025 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3026 if (--ml->count == 0) {
3027 struct net_device *dev;
3028 *mlp = ml->next;
3029 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3030 if (dev)
3031 packet_dev_mc(dev, ml, -1);
3032 kfree(ml);
3033 }
3034 rtnl_unlock();
3035 return 0;
3036 }
3037 }
3038 rtnl_unlock();
3039 return -EADDRNOTAVAIL;
3040 }
3041
3042 static void packet_flush_mclist(struct sock *sk)
3043 {
3044 struct packet_sock *po = pkt_sk(sk);
3045 struct packet_mclist *ml;
3046
3047 if (!po->mclist)
3048 return;
3049
3050 rtnl_lock();
3051 while ((ml = po->mclist) != NULL) {
3052 struct net_device *dev;
3053
3054 po->mclist = ml->next;
3055 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3056 if (dev != NULL)
3057 packet_dev_mc(dev, ml, -1);
3058 kfree(ml);
3059 }
3060 rtnl_unlock();
3061 }
3062
3063 static int
3064 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3065 {
3066 struct sock *sk = sock->sk;
3067 struct packet_sock *po = pkt_sk(sk);
3068 int ret;
3069
3070 if (level != SOL_PACKET)
3071 return -ENOPROTOOPT;
3072
3073 switch (optname) {
3074 case PACKET_ADD_MEMBERSHIP:
3075 case PACKET_DROP_MEMBERSHIP:
3076 {
3077 struct packet_mreq_max mreq;
3078 int len = optlen;
3079 memset(&mreq, 0, sizeof(mreq));
3080 if (len < sizeof(struct packet_mreq))
3081 return -EINVAL;
3082 if (len > sizeof(mreq))
3083 len = sizeof(mreq);
3084 if (copy_from_user(&mreq, optval, len))
3085 return -EFAULT;
3086 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3087 return -EINVAL;
3088 if (optname == PACKET_ADD_MEMBERSHIP)
3089 ret = packet_mc_add(sk, &mreq);
3090 else
3091 ret = packet_mc_drop(sk, &mreq);
3092 return ret;
3093 }
3094
3095 case PACKET_RX_RING:
3096 case PACKET_TX_RING:
3097 {
3098 union tpacket_req_u req_u;
3099 int len;
3100
3101 switch (po->tp_version) {
3102 case TPACKET_V1:
3103 case TPACKET_V2:
3104 len = sizeof(req_u.req);
3105 break;
3106 case TPACKET_V3:
3107 default:
3108 len = sizeof(req_u.req3);
3109 break;
3110 }
3111 if (optlen < len)
3112 return -EINVAL;
3113 if (pkt_sk(sk)->has_vnet_hdr)
3114 return -EINVAL;
3115 if (copy_from_user(&req_u.req, optval, len))
3116 return -EFAULT;
3117 return packet_set_ring(sk, &req_u, 0,
3118 optname == PACKET_TX_RING);
3119 }
3120 case PACKET_COPY_THRESH:
3121 {
3122 int val;
3123
3124 if (optlen != sizeof(val))
3125 return -EINVAL;
3126 if (copy_from_user(&val, optval, sizeof(val)))
3127 return -EFAULT;
3128
3129 pkt_sk(sk)->copy_thresh = val;
3130 return 0;
3131 }
3132 case PACKET_VERSION:
3133 {
3134 int val;
3135
3136 if (optlen != sizeof(val))
3137 return -EINVAL;
3138 if (copy_from_user(&val, optval, sizeof(val)))
3139 return -EFAULT;
3140 switch (val) {
3141 case TPACKET_V1:
3142 case TPACKET_V2:
3143 case TPACKET_V3:
3144 break;
3145 default:
3146 return -EINVAL;
3147 }
3148 lock_sock(sk);
3149 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3150 ret = -EBUSY;
3151 } else {
3152 po->tp_version = val;
3153 ret = 0;
3154 }
3155 release_sock(sk);
3156 return ret;
3157 }
3158 case PACKET_RESERVE:
3159 {
3160 unsigned int val;
3161
3162 if (optlen != sizeof(val))
3163 return -EINVAL;
3164 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3165 return -EBUSY;
3166 if (copy_from_user(&val, optval, sizeof(val)))
3167 return -EFAULT;
3168 if (val > INT_MAX)
3169 return -EINVAL;
3170 po->tp_reserve = val;
3171 return 0;
3172 }
3173 case PACKET_LOSS:
3174 {
3175 unsigned int val;
3176
3177 if (optlen != sizeof(val))
3178 return -EINVAL;
3179 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3180 return -EBUSY;
3181 if (copy_from_user(&val, optval, sizeof(val)))
3182 return -EFAULT;
3183 po->tp_loss = !!val;
3184 return 0;
3185 }
3186 case PACKET_AUXDATA:
3187 {
3188 int val;
3189
3190 if (optlen < sizeof(val))
3191 return -EINVAL;
3192 if (copy_from_user(&val, optval, sizeof(val)))
3193 return -EFAULT;
3194
3195 po->auxdata = !!val;
3196 return 0;
3197 }
3198 case PACKET_ORIGDEV:
3199 {
3200 int val;
3201
3202 if (optlen < sizeof(val))
3203 return -EINVAL;
3204 if (copy_from_user(&val, optval, sizeof(val)))
3205 return -EFAULT;
3206
3207 po->origdev = !!val;
3208 return 0;
3209 }
3210 case PACKET_VNET_HDR:
3211 {
3212 int val;
3213
3214 if (sock->type != SOCK_RAW)
3215 return -EINVAL;
3216 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3217 return -EBUSY;
3218 if (optlen < sizeof(val))
3219 return -EINVAL;
3220 if (copy_from_user(&val, optval, sizeof(val)))
3221 return -EFAULT;
3222
3223 po->has_vnet_hdr = !!val;
3224 return 0;
3225 }
3226 case PACKET_TIMESTAMP:
3227 {
3228 int val;
3229
3230 if (optlen != sizeof(val))
3231 return -EINVAL;
3232 if (copy_from_user(&val, optval, sizeof(val)))
3233 return -EFAULT;
3234
3235 po->tp_tstamp = val;
3236 return 0;
3237 }
3238 case PACKET_FANOUT:
3239 {
3240 int val;
3241
3242 if (optlen != sizeof(val))
3243 return -EINVAL;
3244 if (copy_from_user(&val, optval, sizeof(val)))
3245 return -EFAULT;
3246
3247 return fanout_add(sk, val & 0xffff, val >> 16);
3248 }
3249 case PACKET_TX_HAS_OFF:
3250 {
3251 unsigned int val;
3252
3253 if (optlen != sizeof(val))
3254 return -EINVAL;
3255 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3256 return -EBUSY;
3257 if (copy_from_user(&val, optval, sizeof(val)))
3258 return -EFAULT;
3259 po->tp_tx_has_off = !!val;
3260 return 0;
3261 }
3262 default:
3263 return -ENOPROTOOPT;
3264 }
3265 }
3266
3267 static int packet_getsockopt(struct socket *sock, int level, int optname,
3268 char __user *optval, int __user *optlen)
3269 {
3270 int len;
3271 int val, lv = sizeof(val);
3272 struct sock *sk = sock->sk;
3273 struct packet_sock *po = pkt_sk(sk);
3274 void *data = &val;
3275 union tpacket_stats_u st;
3276
3277 if (level != SOL_PACKET)
3278 return -ENOPROTOOPT;
3279
3280 if (get_user(len, optlen))
3281 return -EFAULT;
3282
3283 if (len < 0)
3284 return -EINVAL;
3285
3286 switch (optname) {
3287 case PACKET_STATISTICS:
3288 spin_lock_bh(&sk->sk_receive_queue.lock);
3289 memcpy(&st, &po->stats, sizeof(st));
3290 memset(&po->stats, 0, sizeof(po->stats));
3291 spin_unlock_bh(&sk->sk_receive_queue.lock);
3292
3293 if (po->tp_version == TPACKET_V3) {
3294 lv = sizeof(struct tpacket_stats_v3);
3295 st.stats3.tp_packets += st.stats3.tp_drops;
3296 data = &st.stats3;
3297 } else {
3298 lv = sizeof(struct tpacket_stats);
3299 st.stats1.tp_packets += st.stats1.tp_drops;
3300 data = &st.stats1;
3301 }
3302
3303 break;
3304 case PACKET_AUXDATA:
3305 val = po->auxdata;
3306 break;
3307 case PACKET_ORIGDEV:
3308 val = po->origdev;
3309 break;
3310 case PACKET_VNET_HDR:
3311 val = po->has_vnet_hdr;
3312 break;
3313 case PACKET_VERSION:
3314 val = po->tp_version;
3315 break;
3316 case PACKET_HDRLEN:
3317 if (len > sizeof(int))
3318 len = sizeof(int);
3319 if (copy_from_user(&val, optval, len))
3320 return -EFAULT;
3321 switch (val) {
3322 case TPACKET_V1:
3323 val = sizeof(struct tpacket_hdr);
3324 break;
3325 case TPACKET_V2:
3326 val = sizeof(struct tpacket2_hdr);
3327 break;
3328 case TPACKET_V3:
3329 val = sizeof(struct tpacket3_hdr);
3330 break;
3331 default:
3332 return -EINVAL;
3333 }
3334 break;
3335 case PACKET_RESERVE:
3336 val = po->tp_reserve;
3337 break;
3338 case PACKET_LOSS:
3339 val = po->tp_loss;
3340 break;
3341 case PACKET_TIMESTAMP:
3342 val = po->tp_tstamp;
3343 break;
3344 case PACKET_FANOUT:
3345 val = (po->fanout ?
3346 ((u32)po->fanout->id |
3347 ((u32)po->fanout->type << 16) |
3348 ((u32)po->fanout->flags << 24)) :
3349 0);
3350 break;
3351 case PACKET_TX_HAS_OFF:
3352 val = po->tp_tx_has_off;
3353 break;
3354 default:
3355 return -ENOPROTOOPT;
3356 }
3357
3358 if (len > lv)
3359 len = lv;
3360 if (put_user(len, optlen))
3361 return -EFAULT;
3362 if (copy_to_user(optval, data, len))
3363 return -EFAULT;
3364 return 0;
3365 }
3366
3367
3368 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3369 {
3370 struct sock *sk;
3371 struct net_device *dev = data;
3372 struct net *net = dev_net(dev);
3373
3374 rcu_read_lock();
3375 sk_for_each_rcu(sk, &net->packet.sklist) {
3376 struct packet_sock *po = pkt_sk(sk);
3377
3378 switch (msg) {
3379 case NETDEV_UNREGISTER:
3380 if (po->mclist)
3381 packet_dev_mclist(dev, po->mclist, -1);
3382 /* fallthrough */
3383
3384 case NETDEV_DOWN:
3385 if (dev->ifindex == po->ifindex) {
3386 spin_lock(&po->bind_lock);
3387 if (po->running) {
3388 __unregister_prot_hook(sk, false);
3389 sk->sk_err = ENETDOWN;
3390 if (!sock_flag(sk, SOCK_DEAD))
3391 sk->sk_error_report(sk);
3392 }
3393 if (msg == NETDEV_UNREGISTER) {
3394 packet_cached_dev_reset(po);
3395 po->ifindex = -1;
3396 if (po->prot_hook.dev)
3397 dev_put(po->prot_hook.dev);
3398 po->prot_hook.dev = NULL;
3399 }
3400 spin_unlock(&po->bind_lock);
3401 }
3402 break;
3403 case NETDEV_UP:
3404 if (dev->ifindex == po->ifindex) {
3405 spin_lock(&po->bind_lock);
3406 if (po->num)
3407 register_prot_hook(sk);
3408 spin_unlock(&po->bind_lock);
3409 }
3410 break;
3411 }
3412 }
3413 rcu_read_unlock();
3414 return NOTIFY_DONE;
3415 }
3416
3417
3418 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3419 unsigned long arg)
3420 {
3421 struct sock *sk = sock->sk;
3422
3423 switch (cmd) {
3424 case SIOCOUTQ:
3425 {
3426 int amount = sk_wmem_alloc_get(sk);
3427
3428 return put_user(amount, (int __user *)arg);
3429 }
3430 case SIOCINQ:
3431 {
3432 struct sk_buff *skb;
3433 int amount = 0;
3434
3435 spin_lock_bh(&sk->sk_receive_queue.lock);
3436 skb = skb_peek(&sk->sk_receive_queue);
3437 if (skb)
3438 amount = skb->len;
3439 spin_unlock_bh(&sk->sk_receive_queue.lock);
3440 return put_user(amount, (int __user *)arg);
3441 }
3442 case SIOCGSTAMP:
3443 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3444 case SIOCGSTAMPNS:
3445 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3446
3447 #ifdef CONFIG_INET
3448 case SIOCADDRT:
3449 case SIOCDELRT:
3450 case SIOCDARP:
3451 case SIOCGARP:
3452 case SIOCSARP:
3453 case SIOCGIFADDR:
3454 case SIOCSIFADDR:
3455 case SIOCGIFBRDADDR:
3456 case SIOCSIFBRDADDR:
3457 case SIOCGIFNETMASK:
3458 case SIOCSIFNETMASK:
3459 case SIOCGIFDSTADDR:
3460 case SIOCSIFDSTADDR:
3461 case SIOCSIFFLAGS:
3462 return inet_dgram_ops.ioctl(sock, cmd, arg);
3463 #endif
3464
3465 default:
3466 return -ENOIOCTLCMD;
3467 }
3468 return 0;
3469 }
3470
3471 static unsigned int packet_poll(struct file *file, struct socket *sock,
3472 poll_table *wait)
3473 {
3474 struct sock *sk = sock->sk;
3475 struct packet_sock *po = pkt_sk(sk);
3476 unsigned int mask = datagram_poll(file, sock, wait);
3477
3478 spin_lock_bh(&sk->sk_receive_queue.lock);
3479 if (po->rx_ring.pg_vec) {
3480 if (!packet_previous_rx_frame(po, &po->rx_ring,
3481 TP_STATUS_KERNEL))
3482 mask |= POLLIN | POLLRDNORM;
3483 }
3484 spin_unlock_bh(&sk->sk_receive_queue.lock);
3485 spin_lock_bh(&sk->sk_write_queue.lock);
3486 if (po->tx_ring.pg_vec) {
3487 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3488 mask |= POLLOUT | POLLWRNORM;
3489 }
3490 spin_unlock_bh(&sk->sk_write_queue.lock);
3491 return mask;
3492 }
3493
3494
3495 /* Dirty? Well, I still did not learn better way to account
3496 * for user mmaps.
3497 */
3498
3499 static void packet_mm_open(struct vm_area_struct *vma)
3500 {
3501 struct file *file = vma->vm_file;
3502 struct socket *sock = file->private_data;
3503 struct sock *sk = sock->sk;
3504
3505 if (sk)
3506 atomic_inc(&pkt_sk(sk)->mapped);
3507 }
3508
3509 static void packet_mm_close(struct vm_area_struct *vma)
3510 {
3511 struct file *file = vma->vm_file;
3512 struct socket *sock = file->private_data;
3513 struct sock *sk = sock->sk;
3514
3515 if (sk)
3516 atomic_dec(&pkt_sk(sk)->mapped);
3517 }
3518
3519 static const struct vm_operations_struct packet_mmap_ops = {
3520 .open = packet_mm_open,
3521 .close = packet_mm_close,
3522 };
3523
3524 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3525 unsigned int len)
3526 {
3527 int i;
3528
3529 for (i = 0; i < len; i++) {
3530 if (likely(pg_vec[i].buffer)) {
3531 if (is_vmalloc_addr(pg_vec[i].buffer))
3532 vfree(pg_vec[i].buffer);
3533 else
3534 free_pages((unsigned long)pg_vec[i].buffer,
3535 order);
3536 pg_vec[i].buffer = NULL;
3537 }
3538 }
3539 kfree(pg_vec);
3540 }
3541
3542 static char *alloc_one_pg_vec_page(unsigned long order)
3543 {
3544 char *buffer = NULL;
3545 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3546 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3547
3548 buffer = (char *) __get_free_pages(gfp_flags, order);
3549
3550 if (buffer)
3551 return buffer;
3552
3553 /*
3554 * __get_free_pages failed, fall back to vmalloc
3555 */
3556 buffer = vzalloc((1 << order) * PAGE_SIZE);
3557
3558 if (buffer)
3559 return buffer;
3560
3561 /*
3562 * vmalloc failed, lets dig into swap here
3563 */
3564 gfp_flags &= ~__GFP_NORETRY;
3565 buffer = (char *)__get_free_pages(gfp_flags, order);
3566 if (buffer)
3567 return buffer;
3568
3569 /*
3570 * complete and utter failure
3571 */
3572 return NULL;
3573 }
3574
3575 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3576 {
3577 unsigned int block_nr = req->tp_block_nr;
3578 struct pgv *pg_vec;
3579 int i;
3580
3581 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3582 if (unlikely(!pg_vec))
3583 goto out;
3584
3585 for (i = 0; i < block_nr; i++) {
3586 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3587 if (unlikely(!pg_vec[i].buffer))
3588 goto out_free_pgvec;
3589 }
3590
3591 out:
3592 return pg_vec;
3593
3594 out_free_pgvec:
3595 free_pg_vec(pg_vec, order, block_nr);
3596 pg_vec = NULL;
3597 goto out;
3598 }
3599
3600 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3601 int closing, int tx_ring)
3602 {
3603 struct pgv *pg_vec = NULL;
3604 struct packet_sock *po = pkt_sk(sk);
3605 int was_running, order = 0;
3606 struct packet_ring_buffer *rb;
3607 struct sk_buff_head *rb_queue;
3608 __be16 num;
3609 int err = -EINVAL;
3610 /* Added to avoid minimal code churn */
3611 struct tpacket_req *req = &req_u->req;
3612
3613 lock_sock(sk);
3614 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3615 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3616 WARN(1, "Tx-ring is not supported.\n");
3617 goto out;
3618 }
3619
3620 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3621 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3622
3623 err = -EBUSY;
3624 if (!closing) {
3625 if (atomic_read(&po->mapped))
3626 goto out;
3627 if (atomic_read(&rb->pending))
3628 goto out;
3629 }
3630
3631 if (req->tp_block_nr) {
3632 /* Sanity tests and some calculations */
3633 err = -EBUSY;
3634 if (unlikely(rb->pg_vec))
3635 goto out;
3636
3637 switch (po->tp_version) {
3638 case TPACKET_V1:
3639 po->tp_hdrlen = TPACKET_HDRLEN;
3640 break;
3641 case TPACKET_V2:
3642 po->tp_hdrlen = TPACKET2_HDRLEN;
3643 break;
3644 case TPACKET_V3:
3645 po->tp_hdrlen = TPACKET3_HDRLEN;
3646 break;
3647 }
3648
3649 err = -EINVAL;
3650 if (unlikely((int)req->tp_block_size <= 0))
3651 goto out;
3652 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3653 goto out;
3654 if (po->tp_version >= TPACKET_V3 &&
3655 req->tp_block_size <=
3656 BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv))
3657 goto out;
3658 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3659 po->tp_reserve))
3660 goto out;
3661 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3662 goto out;
3663
3664 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3665 if (unlikely(rb->frames_per_block <= 0))
3666 goto out;
3667 if (unlikely(req->tp_block_size > UINT_MAX / req->tp_block_nr))
3668 goto out;
3669 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3670 req->tp_frame_nr))
3671 goto out;
3672
3673 err = -ENOMEM;
3674 order = get_order(req->tp_block_size);
3675 pg_vec = alloc_pg_vec(req, order);
3676 if (unlikely(!pg_vec))
3677 goto out;
3678 switch (po->tp_version) {
3679 case TPACKET_V3:
3680 /* Transmit path is not supported. We checked
3681 * it above but just being paranoid
3682 */
3683 if (!tx_ring)
3684 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3685 break;
3686 default:
3687 break;
3688 }
3689 }
3690 /* Done */
3691 else {
3692 err = -EINVAL;
3693 if (unlikely(req->tp_frame_nr))
3694 goto out;
3695 }
3696
3697
3698 /* Detach socket from network */
3699 spin_lock(&po->bind_lock);
3700 was_running = po->running;
3701 num = po->num;
3702 if (was_running) {
3703 po->num = 0;
3704 __unregister_prot_hook(sk, false);
3705 }
3706 spin_unlock(&po->bind_lock);
3707
3708 synchronize_net();
3709
3710 err = -EBUSY;
3711 mutex_lock(&po->pg_vec_lock);
3712 if (closing || atomic_read(&po->mapped) == 0) {
3713 err = 0;
3714 spin_lock_bh(&rb_queue->lock);
3715 swap(rb->pg_vec, pg_vec);
3716 rb->frame_max = (req->tp_frame_nr - 1);
3717 rb->head = 0;
3718 rb->frame_size = req->tp_frame_size;
3719 spin_unlock_bh(&rb_queue->lock);
3720
3721 swap(rb->pg_vec_order, order);
3722 swap(rb->pg_vec_len, req->tp_block_nr);
3723
3724 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3725 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3726 tpacket_rcv : packet_rcv;
3727 skb_queue_purge(rb_queue);
3728 if (atomic_read(&po->mapped))
3729 pr_err("packet_mmap: vma is busy: %d\n",
3730 atomic_read(&po->mapped));
3731 }
3732 mutex_unlock(&po->pg_vec_lock);
3733
3734 spin_lock(&po->bind_lock);
3735 if (was_running) {
3736 po->num = num;
3737 register_prot_hook(sk);
3738 }
3739 spin_unlock(&po->bind_lock);
3740 if (closing && (po->tp_version > TPACKET_V2)) {
3741 /* Because we don't support block-based V3 on tx-ring */
3742 if (!tx_ring)
3743 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3744 }
3745
3746 if (pg_vec)
3747 free_pg_vec(pg_vec, order, req->tp_block_nr);
3748 out:
3749 release_sock(sk);
3750 return err;
3751 }
3752
3753 static int packet_mmap(struct file *file, struct socket *sock,
3754 struct vm_area_struct *vma)
3755 {
3756 struct sock *sk = sock->sk;
3757 struct packet_sock *po = pkt_sk(sk);
3758 unsigned long size, expected_size;
3759 struct packet_ring_buffer *rb;
3760 unsigned long start;
3761 int err = -EINVAL;
3762 int i;
3763
3764 if (vma->vm_pgoff)
3765 return -EINVAL;
3766
3767 mutex_lock(&po->pg_vec_lock);
3768
3769 expected_size = 0;
3770 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3771 if (rb->pg_vec) {
3772 expected_size += rb->pg_vec_len
3773 * rb->pg_vec_pages
3774 * PAGE_SIZE;
3775 }
3776 }
3777
3778 if (expected_size == 0)
3779 goto out;
3780
3781 size = vma->vm_end - vma->vm_start;
3782 if (size != expected_size)
3783 goto out;
3784
3785 start = vma->vm_start;
3786 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3787 if (rb->pg_vec == NULL)
3788 continue;
3789
3790 for (i = 0; i < rb->pg_vec_len; i++) {
3791 struct page *page;
3792 void *kaddr = rb->pg_vec[i].buffer;
3793 int pg_num;
3794
3795 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3796 page = pgv_to_page(kaddr);
3797 err = vm_insert_page(vma, start, page);
3798 if (unlikely(err))
3799 goto out;
3800 start += PAGE_SIZE;
3801 kaddr += PAGE_SIZE;
3802 }
3803 }
3804 }
3805
3806 atomic_inc(&po->mapped);
3807 vma->vm_ops = &packet_mmap_ops;
3808 err = 0;
3809
3810 out:
3811 mutex_unlock(&po->pg_vec_lock);
3812 return err;
3813 }
3814
3815 static const struct proto_ops packet_ops_spkt = {
3816 .family = PF_PACKET,
3817 .owner = THIS_MODULE,
3818 .release = packet_release,
3819 .bind = packet_bind_spkt,
3820 .connect = sock_no_connect,
3821 .socketpair = sock_no_socketpair,
3822 .accept = sock_no_accept,
3823 .getname = packet_getname_spkt,
3824 .poll = datagram_poll,
3825 .ioctl = packet_ioctl,
3826 .listen = sock_no_listen,
3827 .shutdown = sock_no_shutdown,
3828 .setsockopt = sock_no_setsockopt,
3829 .getsockopt = sock_no_getsockopt,
3830 .sendmsg = packet_sendmsg_spkt,
3831 .recvmsg = packet_recvmsg,
3832 .mmap = sock_no_mmap,
3833 .sendpage = sock_no_sendpage,
3834 };
3835
3836 static const struct proto_ops packet_ops = {
3837 .family = PF_PACKET,
3838 .owner = THIS_MODULE,
3839 .release = packet_release,
3840 .bind = packet_bind,
3841 .connect = sock_no_connect,
3842 .socketpair = sock_no_socketpair,
3843 .accept = sock_no_accept,
3844 .getname = packet_getname,
3845 .poll = packet_poll,
3846 .ioctl = packet_ioctl,
3847 .listen = sock_no_listen,
3848 .shutdown = sock_no_shutdown,
3849 .setsockopt = packet_setsockopt,
3850 .getsockopt = packet_getsockopt,
3851 .sendmsg = packet_sendmsg,
3852 .recvmsg = packet_recvmsg,
3853 .mmap = packet_mmap,
3854 .sendpage = sock_no_sendpage,
3855 };
3856
3857 static const struct net_proto_family packet_family_ops = {
3858 .family = PF_PACKET,
3859 .create = packet_create,
3860 .owner = THIS_MODULE,
3861 };
3862
3863 static struct notifier_block packet_netdev_notifier = {
3864 .notifier_call = packet_notifier,
3865 };
3866
3867 #ifdef CONFIG_PROC_FS
3868
3869 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3870 __acquires(RCU)
3871 {
3872 struct net *net = seq_file_net(seq);
3873
3874 rcu_read_lock();
3875 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3876 }
3877
3878 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3879 {
3880 struct net *net = seq_file_net(seq);
3881 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3882 }
3883
3884 static void packet_seq_stop(struct seq_file *seq, void *v)
3885 __releases(RCU)
3886 {
3887 rcu_read_unlock();
3888 }
3889
3890 static int packet_seq_show(struct seq_file *seq, void *v)
3891 {
3892 if (v == SEQ_START_TOKEN)
3893 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3894 else {
3895 struct sock *s = sk_entry(v);
3896 const struct packet_sock *po = pkt_sk(s);
3897
3898 seq_printf(seq,
3899 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3900 s,
3901 atomic_read(&s->sk_refcnt),
3902 s->sk_type,
3903 ntohs(po->num),
3904 po->ifindex,
3905 po->running,
3906 atomic_read(&s->sk_rmem_alloc),
3907 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
3908 sock_i_ino(s));
3909 }
3910
3911 return 0;
3912 }
3913
3914 static const struct seq_operations packet_seq_ops = {
3915 .start = packet_seq_start,
3916 .next = packet_seq_next,
3917 .stop = packet_seq_stop,
3918 .show = packet_seq_show,
3919 };
3920
3921 static int packet_seq_open(struct inode *inode, struct file *file)
3922 {
3923 return seq_open_net(inode, file, &packet_seq_ops,
3924 sizeof(struct seq_net_private));
3925 }
3926
3927 static const struct file_operations packet_seq_fops = {
3928 .owner = THIS_MODULE,
3929 .open = packet_seq_open,
3930 .read = seq_read,
3931 .llseek = seq_lseek,
3932 .release = seq_release_net,
3933 };
3934
3935 #endif
3936
3937 static int __net_init packet_net_init(struct net *net)
3938 {
3939 mutex_init(&net->packet.sklist_lock);
3940 INIT_HLIST_HEAD(&net->packet.sklist);
3941
3942 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
3943 return -ENOMEM;
3944
3945 return 0;
3946 }
3947
3948 static void __net_exit packet_net_exit(struct net *net)
3949 {
3950 remove_proc_entry("packet", net->proc_net);
3951 }
3952
3953 static struct pernet_operations packet_net_ops = {
3954 .init = packet_net_init,
3955 .exit = packet_net_exit,
3956 };
3957
3958
3959 static void __exit packet_exit(void)
3960 {
3961 unregister_netdevice_notifier(&packet_netdev_notifier);
3962 unregister_pernet_subsys(&packet_net_ops);
3963 sock_unregister(PF_PACKET);
3964 proto_unregister(&packet_proto);
3965 }
3966
3967 static int __init packet_init(void)
3968 {
3969 int rc = proto_register(&packet_proto, 0);
3970
3971 if (rc != 0)
3972 goto out;
3973
3974 sock_register(&packet_family_ops);
3975 register_pernet_subsys(&packet_net_ops);
3976 register_netdevice_notifier(&packet_netdev_notifier);
3977 out:
3978 return rc;
3979 }
3980
3981 module_init(packet_init);
3982 module_exit(packet_exit);
3983 MODULE_LICENSE("GPL");
3984 MODULE_ALIAS_NETPROTO(PF_PACKET);
kernel source for telekom puls (alcatel/mediatek)