?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
bnx2x: Correct EEE statistics gathering
[linux-2.6.git] / net / packet / af_packet.c
blobceaca7c134a011b659bc439dff6de58269b532b4
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 /*
97 Assumptions:
98 - if device has no dev->hard_header routine, it adds and removes ll header
99 inside itself. In this case ll header is invisible outside of device,
100 but higher levels still should reserve dev->hard_header_len.
101 Some devices are enough clever to reallocate skb, when header
102 will not fit to reserved space (tunnel), another ones are silly
103 (PPP).
104 - packet socket receives packets with pulled ll header,
105 so that SOCK_RAW should push it back.
106
107 On receive:
108 -----------
109
110 Incoming, dev->hard_header!=NULL
111 mac_header -> ll header
112 data -> data
113
114 Outgoing, dev->hard_header!=NULL
115 mac_header -> ll header
116 data -> ll header
117
118 Incoming, dev->hard_header==NULL
119 mac_header -> UNKNOWN position. It is very likely, that it points to ll
120 header. PPP makes it, that is wrong, because introduce
121 assymetry between rx and tx paths.
122 data -> data
123
124 Outgoing, dev->hard_header==NULL
125 mac_header -> data. ll header is still not built!
126 data -> data
127
128 Resume
129 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
130
131
132 On transmit:
133 ------------
134
135 dev->hard_header != NULL
136 mac_header -> ll header
137 data -> ll header
138
139 dev->hard_header == NULL (ll header is added by device, we cannot control it)
140 mac_header -> data
141 data -> data
142
143 We should set nh.raw on output to correct posistion,
144 packet classifier depends on it.
145 */
146
147 /* Private packet socket structures. */
148
149 struct packet_mclist {
150 struct packet_mclist *next;
151 int ifindex;
152 int count;
153 unsigned short type;
154 unsigned short alen;
155 unsigned char addr[MAX_ADDR_LEN];
156 };
157 /* identical to struct packet_mreq except it has
158 * a longer address field.
159 */
160 struct packet_mreq_max {
161 int mr_ifindex;
162 unsigned short mr_type;
163 unsigned short mr_alen;
164 unsigned char mr_address[MAX_ADDR_LEN];
165 };
166
167 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
168 int closing, int tx_ring);
169
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 /* kbdq - kernel block descriptor queue */
179 struct tpacket_kbdq_core {
180 struct pgv *pkbdq;
181 unsigned int feature_req_word;
182 unsigned int hdrlen;
183 unsigned char reset_pending_on_curr_blk;
184 unsigned char delete_blk_timer;
185 unsigned short kactive_blk_num;
186 unsigned short blk_sizeof_priv;
187
188 /* last_kactive_blk_num:
189 * trick to see if user-space has caught up
190 * in order to avoid refreshing timer when every single pkt arrives.
191 */
192 unsigned short last_kactive_blk_num;
193
194 char *pkblk_start;
195 char *pkblk_end;
196 int kblk_size;
197 unsigned int knum_blocks;
198 uint64_t knxt_seq_num;
199 char *prev;
200 char *nxt_offset;
201 struct sk_buff *skb;
202
203 atomic_t blk_fill_in_prog;
204
205 /* Default is set to 8ms */
206 #define DEFAULT_PRB_RETIRE_TOV (8)
207
208 unsigned short retire_blk_tov;
209 unsigned short version;
210 unsigned long tov_in_jiffies;
211
212 /* timer to retire an outstanding block */
213 struct timer_list retire_blk_timer;
214 };
215
216 #define PGV_FROM_VMALLOC 1
217 struct pgv {
218 char *buffer;
219 };
220
221 struct packet_ring_buffer {
222 struct pgv *pg_vec;
223 unsigned int head;
224 unsigned int frames_per_block;
225 unsigned int frame_size;
226 unsigned int frame_max;
227
228 unsigned int pg_vec_order;
229 unsigned int pg_vec_pages;
230 unsigned int pg_vec_len;
231
232 struct tpacket_kbdq_core prb_bdqc;
233 atomic_t pending;
234 };
235
236 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
237 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
238 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
239 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
240 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
241 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
242 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
243
244 struct packet_sock;
245 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
246
247 static void *packet_previous_frame(struct packet_sock *po,
248 struct packet_ring_buffer *rb,
249 int status);
250 static void packet_increment_head(struct packet_ring_buffer *buff);
251 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
252 struct tpacket_block_desc *);
253 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
254 struct packet_sock *);
255 static void prb_retire_current_block(struct tpacket_kbdq_core *,
256 struct packet_sock *, unsigned int status);
257 static int prb_queue_frozen(struct tpacket_kbdq_core *);
258 static void prb_open_block(struct tpacket_kbdq_core *,
259 struct tpacket_block_desc *);
260 static void prb_retire_rx_blk_timer_expired(unsigned long);
261 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
262 static void prb_init_blk_timer(struct packet_sock *,
263 struct tpacket_kbdq_core *,
264 void (*func) (unsigned long));
265 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
266 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
267 struct tpacket3_hdr *);
268 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
269 struct tpacket3_hdr *);
270 static void packet_flush_mclist(struct sock *sk);
271
272 struct packet_fanout;
273 struct packet_sock {
274 /* struct sock has to be the first member of packet_sock */
275 struct sock sk;
276 struct packet_fanout *fanout;
277 struct tpacket_stats stats;
278 union tpacket_stats_u stats_u;
279 struct packet_ring_buffer rx_ring;
280 struct packet_ring_buffer tx_ring;
281 int copy_thresh;
282 spinlock_t bind_lock;
283 struct mutex pg_vec_lock;
284 unsigned int running:1, /* prot_hook is attached*/
285 auxdata:1,
286 origdev:1,
287 has_vnet_hdr:1;
288 int ifindex; /* bound device */
289 __be16 num;
290 struct packet_mclist *mclist;
291 atomic_t mapped;
292 enum tpacket_versions tp_version;
293 unsigned int tp_hdrlen;
294 unsigned int tp_reserve;
295 unsigned int tp_loss:1;
296 unsigned int tp_tstamp;
297 struct packet_type prot_hook ____cacheline_aligned_in_smp;
298 };
299
300 #define PACKET_FANOUT_MAX 256
301
302 struct packet_fanout {
303 #ifdef CONFIG_NET_NS
304 struct net *net;
305 #endif
306 unsigned int num_members;
307 u16 id;
308 u8 type;
309 u8 defrag;
310 atomic_t rr_cur;
311 struct list_head list;
312 struct sock *arr[PACKET_FANOUT_MAX];
313 spinlock_t lock;
314 atomic_t sk_ref;
315 struct packet_type prot_hook ____cacheline_aligned_in_smp;
316 };
317
318 struct packet_skb_cb {
319 unsigned int origlen;
320 union {
321 struct sockaddr_pkt pkt;
322 struct sockaddr_ll ll;
323 } sa;
324 };
325
326 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
327
328 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
329 #define GET_PBLOCK_DESC(x, bid) \
330 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
331 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
332 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
333 #define GET_NEXT_PRB_BLK_NUM(x) \
334 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
335 ((x)->kactive_blk_num+1) : 0)
336
337 static struct packet_sock *pkt_sk(struct sock *sk)
338 {
339 return (struct packet_sock *)sk;
340 }
341
342 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
343 static void __fanout_link(struct sock *sk, struct packet_sock *po);
344
345 /* register_prot_hook must be invoked with the po->bind_lock held,
346 * or from a context in which asynchronous accesses to the packet
347 * socket is not possible (packet_create()).
348 */
349 static void register_prot_hook(struct sock *sk)
350 {
351 struct packet_sock *po = pkt_sk(sk);
352 if (!po->running) {
353 if (po->fanout)
354 __fanout_link(sk, po);
355 else
356 dev_add_pack(&po->prot_hook);
357 sock_hold(sk);
358 po->running = 1;
359 }
360 }
361
362 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
363 * held. If the sync parameter is true, we will temporarily drop
364 * the po->bind_lock and do a synchronize_net to make sure no
365 * asynchronous packet processing paths still refer to the elements
366 * of po->prot_hook. If the sync parameter is false, it is the
367 * callers responsibility to take care of this.
368 */
369 static void __unregister_prot_hook(struct sock *sk, bool sync)
370 {
371 struct packet_sock *po = pkt_sk(sk);
372
373 po->running = 0;
374 if (po->fanout)
375 __fanout_unlink(sk, po);
376 else
377 __dev_remove_pack(&po->prot_hook);
378 __sock_put(sk);
379
380 if (sync) {
381 spin_unlock(&po->bind_lock);
382 synchronize_net();
383 spin_lock(&po->bind_lock);
384 }
385 }
386
387 static void unregister_prot_hook(struct sock *sk, bool sync)
388 {
389 struct packet_sock *po = pkt_sk(sk);
390
391 if (po->running)
392 __unregister_prot_hook(sk, sync);
393 }
394
395 static inline __pure struct page *pgv_to_page(void *addr)
396 {
397 if (is_vmalloc_addr(addr))
398 return vmalloc_to_page(addr);
399 return virt_to_page(addr);
400 }
401
402 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
403 {
404 union {
405 struct tpacket_hdr *h1;
406 struct tpacket2_hdr *h2;
407 void *raw;
408 } h;
409
410 h.raw = frame;
411 switch (po->tp_version) {
412 case TPACKET_V1:
413 h.h1->tp_status = status;
414 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
415 break;
416 case TPACKET_V2:
417 h.h2->tp_status = status;
418 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
419 break;
420 case TPACKET_V3:
421 default:
422 WARN(1, "TPACKET version not supported.\n");
423 BUG();
424 }
425
426 smp_wmb();
427 }
428
429 static int __packet_get_status(struct packet_sock *po, void *frame)
430 {
431 union {
432 struct tpacket_hdr *h1;
433 struct tpacket2_hdr *h2;
434 void *raw;
435 } h;
436
437 smp_rmb();
438
439 h.raw = frame;
440 switch (po->tp_version) {
441 case TPACKET_V1:
442 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
443 return h.h1->tp_status;
444 case TPACKET_V2:
445 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
446 return h.h2->tp_status;
447 case TPACKET_V3:
448 default:
449 WARN(1, "TPACKET version not supported.\n");
450 BUG();
451 return 0;
452 }
453 }
454
455 static void *packet_lookup_frame(struct packet_sock *po,
456 struct packet_ring_buffer *rb,
457 unsigned int position,
458 int status)
459 {
460 unsigned int pg_vec_pos, frame_offset;
461 union {
462 struct tpacket_hdr *h1;
463 struct tpacket2_hdr *h2;
464 void *raw;
465 } h;
466
467 pg_vec_pos = position / rb->frames_per_block;
468 frame_offset = position % rb->frames_per_block;
469
470 h.raw = rb->pg_vec[pg_vec_pos].buffer +
471 (frame_offset * rb->frame_size);
472
473 if (status != __packet_get_status(po, h.raw))
474 return NULL;
475
476 return h.raw;
477 }
478
479 static void *packet_current_frame(struct packet_sock *po,
480 struct packet_ring_buffer *rb,
481 int status)
482 {
483 return packet_lookup_frame(po, rb, rb->head, status);
484 }
485
486 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
487 {
488 del_timer_sync(&pkc->retire_blk_timer);
489 }
490
491 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
492 int tx_ring,
493 struct sk_buff_head *rb_queue)
494 {
495 struct tpacket_kbdq_core *pkc;
496
497 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
498
499 spin_lock(&rb_queue->lock);
500 pkc->delete_blk_timer = 1;
501 spin_unlock(&rb_queue->lock);
502
503 prb_del_retire_blk_timer(pkc);
504 }
505
506 static void prb_init_blk_timer(struct packet_sock *po,
507 struct tpacket_kbdq_core *pkc,
508 void (*func) (unsigned long))
509 {
510 init_timer(&pkc->retire_blk_timer);
511 pkc->retire_blk_timer.data = (long)po;
512 pkc->retire_blk_timer.function = func;
513 pkc->retire_blk_timer.expires = jiffies;
514 }
515
516 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
517 {
518 struct tpacket_kbdq_core *pkc;
519
520 if (tx_ring)
521 BUG();
522
523 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
524 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
525 }
526
527 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
528 int blk_size_in_bytes)
529 {
530 struct net_device *dev;
531 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
532 struct ethtool_cmd ecmd;
533 int err;
534 u32 speed;
535
536 rtnl_lock();
537 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
538 if (unlikely(!dev)) {
539 rtnl_unlock();
540 return DEFAULT_PRB_RETIRE_TOV;
541 }
542 err = __ethtool_get_settings(dev, &ecmd);
543 speed = ethtool_cmd_speed(&ecmd);
544 rtnl_unlock();
545 if (!err) {
546 /*
547 * If the link speed is so slow you don't really
548 * need to worry about perf anyways
549 */
550 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
551 return DEFAULT_PRB_RETIRE_TOV;
552 } else {
553 msec = 1;
554 div = speed / 1000;
555 }
556 }
557
558 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
559
560 if (div)
561 mbits /= div;
562
563 tmo = mbits * msec;
564
565 if (div)
566 return tmo+1;
567 return tmo;
568 }
569
570 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
571 union tpacket_req_u *req_u)
572 {
573 p1->feature_req_word = req_u->req3.tp_feature_req_word;
574 }
575
576 static void init_prb_bdqc(struct packet_sock *po,
577 struct packet_ring_buffer *rb,
578 struct pgv *pg_vec,
579 union tpacket_req_u *req_u, int tx_ring)
580 {
581 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
582 struct tpacket_block_desc *pbd;
583
584 memset(p1, 0x0, sizeof(*p1));
585
586 p1->knxt_seq_num = 1;
587 p1->pkbdq = pg_vec;
588 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
589 p1->pkblk_start = pg_vec[0].buffer;
590 p1->kblk_size = req_u->req3.tp_block_size;
591 p1->knum_blocks = req_u->req3.tp_block_nr;
592 p1->hdrlen = po->tp_hdrlen;
593 p1->version = po->tp_version;
594 p1->last_kactive_blk_num = 0;
595 po->stats_u.stats3.tp_freeze_q_cnt = 0;
596 if (req_u->req3.tp_retire_blk_tov)
597 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
598 else
599 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
600 req_u->req3.tp_block_size);
601 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
602 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
603
604 prb_init_ft_ops(p1, req_u);
605 prb_setup_retire_blk_timer(po, tx_ring);
606 prb_open_block(p1, pbd);
607 }
608
609 /* Do NOT update the last_blk_num first.
610 * Assumes sk_buff_head lock is held.
611 */
612 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
613 {
614 mod_timer(&pkc->retire_blk_timer,
615 jiffies + pkc->tov_in_jiffies);
616 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
617 }
618
619 /*
620 * Timer logic:
621 * 1) We refresh the timer only when we open a block.
622 * By doing this we don't waste cycles refreshing the timer
623 * on packet-by-packet basis.
624 *
625 * With a 1MB block-size, on a 1Gbps line, it will take
626 * i) ~8 ms to fill a block + ii) memcpy etc.
627 * In this cut we are not accounting for the memcpy time.
628 *
629 * So, if the user sets the 'tmo' to 10ms then the timer
630 * will never fire while the block is still getting filled
631 * (which is what we want). However, the user could choose
632 * to close a block early and that's fine.
633 *
634 * But when the timer does fire, we check whether or not to refresh it.
635 * Since the tmo granularity is in msecs, it is not too expensive
636 * to refresh the timer, lets say every '8' msecs.
637 * Either the user can set the 'tmo' or we can derive it based on
638 * a) line-speed and b) block-size.
639 * prb_calc_retire_blk_tmo() calculates the tmo.
640 *
641 */
642 static void prb_retire_rx_blk_timer_expired(unsigned long data)
643 {
644 struct packet_sock *po = (struct packet_sock *)data;
645 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
646 unsigned int frozen;
647 struct tpacket_block_desc *pbd;
648
649 spin_lock(&po->sk.sk_receive_queue.lock);
650
651 frozen = prb_queue_frozen(pkc);
652 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
653
654 if (unlikely(pkc->delete_blk_timer))
655 goto out;
656
657 /* We only need to plug the race when the block is partially filled.
658 * tpacket_rcv:
659 * lock(); increment BLOCK_NUM_PKTS; unlock()
660 * copy_bits() is in progress ...
661 * timer fires on other cpu:
662 * we can't retire the current block because copy_bits
663 * is in progress.
664 *
665 */
666 if (BLOCK_NUM_PKTS(pbd)) {
667 while (atomic_read(&pkc->blk_fill_in_prog)) {
668 /* Waiting for skb_copy_bits to finish... */
669 cpu_relax();
670 }
671 }
672
673 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
674 if (!frozen) {
675 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
676 if (!prb_dispatch_next_block(pkc, po))
677 goto refresh_timer;
678 else
679 goto out;
680 } else {
681 /* Case 1. Queue was frozen because user-space was
682 * lagging behind.
683 */
684 if (prb_curr_blk_in_use(pkc, pbd)) {
685 /*
686 * Ok, user-space is still behind.
687 * So just refresh the timer.
688 */
689 goto refresh_timer;
690 } else {
691 /* Case 2. queue was frozen,user-space caught up,
692 * now the link went idle && the timer fired.
693 * We don't have a block to close.So we open this
694 * block and restart the timer.
695 * opening a block thaws the queue,restarts timer
696 * Thawing/timer-refresh is a side effect.
697 */
698 prb_open_block(pkc, pbd);
699 goto out;
700 }
701 }
702 }
703
704 refresh_timer:
705 _prb_refresh_rx_retire_blk_timer(pkc);
706
707 out:
708 spin_unlock(&po->sk.sk_receive_queue.lock);
709 }
710
711 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
712 struct tpacket_block_desc *pbd1, __u32 status)
713 {
714 /* Flush everything minus the block header */
715
716 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
717 u8 *start, *end;
718
719 start = (u8 *)pbd1;
720
721 /* Skip the block header(we know header WILL fit in 4K) */
722 start += PAGE_SIZE;
723
724 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
725 for (; start < end; start += PAGE_SIZE)
726 flush_dcache_page(pgv_to_page(start));
727
728 smp_wmb();
729 #endif
730
731 /* Now update the block status. */
732
733 BLOCK_STATUS(pbd1) = status;
734
735 /* Flush the block header */
736
737 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
738 start = (u8 *)pbd1;
739 flush_dcache_page(pgv_to_page(start));
740
741 smp_wmb();
742 #endif
743 }
744
745 /*
746 * Side effect:
747 *
748 * 1) flush the block
749 * 2) Increment active_blk_num
750 *
751 * Note:We DONT refresh the timer on purpose.
752 * Because almost always the next block will be opened.
753 */
754 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
755 struct tpacket_block_desc *pbd1,
756 struct packet_sock *po, unsigned int stat)
757 {
758 __u32 status = TP_STATUS_USER | stat;
759
760 struct tpacket3_hdr *last_pkt;
761 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
762
763 if (po->stats.tp_drops)
764 status |= TP_STATUS_LOSING;
765
766 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
767 last_pkt->tp_next_offset = 0;
768
769 /* Get the ts of the last pkt */
770 if (BLOCK_NUM_PKTS(pbd1)) {
771 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
772 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
773 } else {
774 /* Ok, we tmo'd - so get the current time */
775 struct timespec ts;
776 getnstimeofday(&ts);
777 h1->ts_last_pkt.ts_sec = ts.tv_sec;
778 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
779 }
780
781 smp_wmb();
782
783 /* Flush the block */
784 prb_flush_block(pkc1, pbd1, status);
785
786 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
787 }
788
789 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
790 {
791 pkc->reset_pending_on_curr_blk = 0;
792 }
793
794 /*
795 * Side effect of opening a block:
796 *
797 * 1) prb_queue is thawed.
798 * 2) retire_blk_timer is refreshed.
799 *
800 */
801 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
802 struct tpacket_block_desc *pbd1)
803 {
804 struct timespec ts;
805 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
806
807 smp_rmb();
808
809 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd1))) {
810
811 /* We could have just memset this but we will lose the
812 * flexibility of making the priv area sticky
813 */
814 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
815 BLOCK_NUM_PKTS(pbd1) = 0;
816 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
817 getnstimeofday(&ts);
818 h1->ts_first_pkt.ts_sec = ts.tv_sec;
819 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
820 pkc1->pkblk_start = (char *)pbd1;
821 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
822 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
823 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
824 pbd1->version = pkc1->version;
825 pkc1->prev = pkc1->nxt_offset;
826 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
827 prb_thaw_queue(pkc1);
828 _prb_refresh_rx_retire_blk_timer(pkc1);
829
830 smp_wmb();
831
832 return;
833 }
834
835 WARN(1, "ERROR block:%p is NOT FREE status:%d kactive_blk_num:%d\n",
836 pbd1, BLOCK_STATUS(pbd1), pkc1->kactive_blk_num);
837 dump_stack();
838 BUG();
839 }
840
841 /*
842 * Queue freeze logic:
843 * 1) Assume tp_block_nr = 8 blocks.
844 * 2) At time 't0', user opens Rx ring.
845 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
846 * 4) user-space is either sleeping or processing block '0'.
847 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
848 * it will close block-7,loop around and try to fill block '0'.
849 * call-flow:
850 * __packet_lookup_frame_in_block
851 * prb_retire_current_block()
852 * prb_dispatch_next_block()
853 * |->(BLOCK_STATUS == USER) evaluates to true
854 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
855 * 6) Now there are two cases:
856 * 6.1) Link goes idle right after the queue is frozen.
857 * But remember, the last open_block() refreshed the timer.
858 * When this timer expires,it will refresh itself so that we can
859 * re-open block-0 in near future.
860 * 6.2) Link is busy and keeps on receiving packets. This is a simple
861 * case and __packet_lookup_frame_in_block will check if block-0
862 * is free and can now be re-used.
863 */
864 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
865 struct packet_sock *po)
866 {
867 pkc->reset_pending_on_curr_blk = 1;
868 po->stats_u.stats3.tp_freeze_q_cnt++;
869 }
870
871 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
872
873 /*
874 * If the next block is free then we will dispatch it
875 * and return a good offset.
876 * Else, we will freeze the queue.
877 * So, caller must check the return value.
878 */
879 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
880 struct packet_sock *po)
881 {
882 struct tpacket_block_desc *pbd;
883
884 smp_rmb();
885
886 /* 1. Get current block num */
887 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
888
889 /* 2. If this block is currently in_use then freeze the queue */
890 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
891 prb_freeze_queue(pkc, po);
892 return NULL;
893 }
894
895 /*
896 * 3.
897 * open this block and return the offset where the first packet
898 * needs to get stored.
899 */
900 prb_open_block(pkc, pbd);
901 return (void *)pkc->nxt_offset;
902 }
903
904 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
905 struct packet_sock *po, unsigned int status)
906 {
907 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
908
909 /* retire/close the current block */
910 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
911 /*
912 * Plug the case where copy_bits() is in progress on
913 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
914 * have space to copy the pkt in the current block and
915 * called prb_retire_current_block()
916 *
917 * We don't need to worry about the TMO case because
918 * the timer-handler already handled this case.
919 */
920 if (!(status & TP_STATUS_BLK_TMO)) {
921 while (atomic_read(&pkc->blk_fill_in_prog)) {
922 /* Waiting for skb_copy_bits to finish... */
923 cpu_relax();
924 }
925 }
926 prb_close_block(pkc, pbd, po, status);
927 return;
928 }
929
930 WARN(1, "ERROR-pbd[%d]:%p\n", pkc->kactive_blk_num, pbd);
931 dump_stack();
932 BUG();
933 }
934
935 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
936 struct tpacket_block_desc *pbd)
937 {
938 return TP_STATUS_USER & BLOCK_STATUS(pbd);
939 }
940
941 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
942 {
943 return pkc->reset_pending_on_curr_blk;
944 }
945
946 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
947 {
948 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
949 atomic_dec(&pkc->blk_fill_in_prog);
950 }
951
952 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
953 struct tpacket3_hdr *ppd)
954 {
955 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
956 }
957
958 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
959 struct tpacket3_hdr *ppd)
960 {
961 ppd->hv1.tp_rxhash = 0;
962 }
963
964 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
965 struct tpacket3_hdr *ppd)
966 {
967 if (vlan_tx_tag_present(pkc->skb)) {
968 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
969 ppd->tp_status = TP_STATUS_VLAN_VALID;
970 } else {
971 ppd->hv1.tp_vlan_tci = ppd->tp_status = 0;
972 }
973 }
974
975 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
976 struct tpacket3_hdr *ppd)
977 {
978 prb_fill_vlan_info(pkc, ppd);
979
980 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
981 prb_fill_rxhash(pkc, ppd);
982 else
983 prb_clear_rxhash(pkc, ppd);
984 }
985
986 static void prb_fill_curr_block(char *curr,
987 struct tpacket_kbdq_core *pkc,
988 struct tpacket_block_desc *pbd,
989 unsigned int len)
990 {
991 struct tpacket3_hdr *ppd;
992
993 ppd = (struct tpacket3_hdr *)curr;
994 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
995 pkc->prev = curr;
996 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
997 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
998 BLOCK_NUM_PKTS(pbd) += 1;
999 atomic_inc(&pkc->blk_fill_in_prog);
1000 prb_run_all_ft_ops(pkc, ppd);
1001 }
1002
1003 /* Assumes caller has the sk->rx_queue.lock */
1004 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1005 struct sk_buff *skb,
1006 int status,
1007 unsigned int len
1008 )
1009 {
1010 struct tpacket_kbdq_core *pkc;
1011 struct tpacket_block_desc *pbd;
1012 char *curr, *end;
1013
1014 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1015 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1016
1017 /* Queue is frozen when user space is lagging behind */
1018 if (prb_queue_frozen(pkc)) {
1019 /*
1020 * Check if that last block which caused the queue to freeze,
1021 * is still in_use by user-space.
1022 */
1023 if (prb_curr_blk_in_use(pkc, pbd)) {
1024 /* Can't record this packet */
1025 return NULL;
1026 } else {
1027 /*
1028 * Ok, the block was released by user-space.
1029 * Now let's open that block.
1030 * opening a block also thaws the queue.
1031 * Thawing is a side effect.
1032 */
1033 prb_open_block(pkc, pbd);
1034 }
1035 }
1036
1037 smp_mb();
1038 curr = pkc->nxt_offset;
1039 pkc->skb = skb;
1040 end = (char *)pbd + pkc->kblk_size;
1041
1042 /* first try the current block */
1043 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1044 prb_fill_curr_block(curr, pkc, pbd, len);
1045 return (void *)curr;
1046 }
1047
1048 /* Ok, close the current block */
1049 prb_retire_current_block(pkc, po, 0);
1050
1051 /* Now, try to dispatch the next block */
1052 curr = (char *)prb_dispatch_next_block(pkc, po);
1053 if (curr) {
1054 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1055 prb_fill_curr_block(curr, pkc, pbd, len);
1056 return (void *)curr;
1057 }
1058
1059 /*
1060 * No free blocks are available.user_space hasn't caught up yet.
1061 * Queue was just frozen and now this packet will get dropped.
1062 */
1063 return NULL;
1064 }
1065
1066 static void *packet_current_rx_frame(struct packet_sock *po,
1067 struct sk_buff *skb,
1068 int status, unsigned int len)
1069 {
1070 char *curr = NULL;
1071 switch (po->tp_version) {
1072 case TPACKET_V1:
1073 case TPACKET_V2:
1074 curr = packet_lookup_frame(po, &po->rx_ring,
1075 po->rx_ring.head, status);
1076 return curr;
1077 case TPACKET_V3:
1078 return __packet_lookup_frame_in_block(po, skb, status, len);
1079 default:
1080 WARN(1, "TPACKET version not supported\n");
1081 BUG();
1082 return 0;
1083 }
1084 }
1085
1086 static void *prb_lookup_block(struct packet_sock *po,
1087 struct packet_ring_buffer *rb,
1088 unsigned int previous,
1089 int status)
1090 {
1091 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1092 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, previous);
1093
1094 if (status != BLOCK_STATUS(pbd))
1095 return NULL;
1096 return pbd;
1097 }
1098
1099 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1100 {
1101 unsigned int prev;
1102 if (rb->prb_bdqc.kactive_blk_num)
1103 prev = rb->prb_bdqc.kactive_blk_num-1;
1104 else
1105 prev = rb->prb_bdqc.knum_blocks-1;
1106 return prev;
1107 }
1108
1109 /* Assumes caller has held the rx_queue.lock */
1110 static void *__prb_previous_block(struct packet_sock *po,
1111 struct packet_ring_buffer *rb,
1112 int status)
1113 {
1114 unsigned int previous = prb_previous_blk_num(rb);
1115 return prb_lookup_block(po, rb, previous, status);
1116 }
1117
1118 static void *packet_previous_rx_frame(struct packet_sock *po,
1119 struct packet_ring_buffer *rb,
1120 int status)
1121 {
1122 if (po->tp_version <= TPACKET_V2)
1123 return packet_previous_frame(po, rb, status);
1124
1125 return __prb_previous_block(po, rb, status);
1126 }
1127
1128 static void packet_increment_rx_head(struct packet_sock *po,
1129 struct packet_ring_buffer *rb)
1130 {
1131 switch (po->tp_version) {
1132 case TPACKET_V1:
1133 case TPACKET_V2:
1134 return packet_increment_head(rb);
1135 case TPACKET_V3:
1136 default:
1137 WARN(1, "TPACKET version not supported.\n");
1138 BUG();
1139 return;
1140 }
1141 }
1142
1143 static void *packet_previous_frame(struct packet_sock *po,
1144 struct packet_ring_buffer *rb,
1145 int status)
1146 {
1147 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1148 return packet_lookup_frame(po, rb, previous, status);
1149 }
1150
1151 static void packet_increment_head(struct packet_ring_buffer *buff)
1152 {
1153 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1154 }
1155
1156 static void packet_sock_destruct(struct sock *sk)
1157 {
1158 skb_queue_purge(&sk->sk_error_queue);
1159
1160 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1161 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1162
1163 if (!sock_flag(sk, SOCK_DEAD)) {
1164 pr_err("Attempt to release alive packet socket: %p\n", sk);
1165 return;
1166 }
1167
1168 sk_refcnt_debug_dec(sk);
1169 }
1170
1171 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1172 {
1173 int x = atomic_read(&f->rr_cur) + 1;
1174
1175 if (x >= num)
1176 x = 0;
1177
1178 return x;
1179 }
1180
1181 static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1182 {
1183 u32 idx, hash = skb->rxhash;
1184
1185 idx = ((u64)hash * num) >> 32;
1186
1187 return f->arr[idx];
1188 }
1189
1190 static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1191 {
1192 int cur, old;
1193
1194 cur = atomic_read(&f->rr_cur);
1195 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1196 fanout_rr_next(f, num))) != cur)
1197 cur = old;
1198 return f->arr[cur];
1199 }
1200
1201 static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1202 {
1203 unsigned int cpu = smp_processor_id();
1204
1205 return f->arr[cpu % num];
1206 }
1207
1208 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1209 struct packet_type *pt, struct net_device *orig_dev)
1210 {
1211 struct packet_fanout *f = pt->af_packet_priv;
1212 unsigned int num = f->num_members;
1213 struct packet_sock *po;
1214 struct sock *sk;
1215
1216 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1217 !num) {
1218 kfree_skb(skb);
1219 return 0;
1220 }
1221
1222 switch (f->type) {
1223 case PACKET_FANOUT_HASH:
1224 default:
1225 if (f->defrag) {
1226 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1227 if (!skb)
1228 return 0;
1229 }
1230 skb_get_rxhash(skb);
1231 sk = fanout_demux_hash(f, skb, num);
1232 break;
1233 case PACKET_FANOUT_LB:
1234 sk = fanout_demux_lb(f, skb, num);
1235 break;
1236 case PACKET_FANOUT_CPU:
1237 sk = fanout_demux_cpu(f, skb, num);
1238 break;
1239 }
1240
1241 po = pkt_sk(sk);
1242
1243 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1244 }
1245
1246 static DEFINE_MUTEX(fanout_mutex);
1247 static LIST_HEAD(fanout_list);
1248
1249 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1250 {
1251 struct packet_fanout *f = po->fanout;
1252
1253 spin_lock(&f->lock);
1254 f->arr[f->num_members] = sk;
1255 smp_wmb();
1256 f->num_members++;
1257 spin_unlock(&f->lock);
1258 }
1259
1260 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1261 {
1262 struct packet_fanout *f = po->fanout;
1263 int i;
1264
1265 spin_lock(&f->lock);
1266 for (i = 0; i < f->num_members; i++) {
1267 if (f->arr[i] == sk)
1268 break;
1269 }
1270 BUG_ON(i >= f->num_members);
1271 f->arr[i] = f->arr[f->num_members - 1];
1272 f->num_members--;
1273 spin_unlock(&f->lock);
1274 }
1275
1276 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1277 {
1278 struct packet_sock *po = pkt_sk(sk);
1279 struct packet_fanout *f, *match;
1280 u8 type = type_flags & 0xff;
1281 u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
1282 int err;
1283
1284 switch (type) {
1285 case PACKET_FANOUT_HASH:
1286 case PACKET_FANOUT_LB:
1287 case PACKET_FANOUT_CPU:
1288 break;
1289 default:
1290 return -EINVAL;
1291 }
1292
1293 if (!po->running)
1294 return -EINVAL;
1295
1296 if (po->fanout)
1297 return -EALREADY;
1298
1299 mutex_lock(&fanout_mutex);
1300 match = NULL;
1301 list_for_each_entry(f, &fanout_list, list) {
1302 if (f->id == id &&
1303 read_pnet(&f->net) == sock_net(sk)) {
1304 match = f;
1305 break;
1306 }
1307 }
1308 err = -EINVAL;
1309 if (match && match->defrag != defrag)
1310 goto out;
1311 if (!match) {
1312 err = -ENOMEM;
1313 match = kzalloc(sizeof(*match), GFP_KERNEL);
1314 if (!match)
1315 goto out;
1316 write_pnet(&match->net, sock_net(sk));
1317 match->id = id;
1318 match->type = type;
1319 match->defrag = defrag;
1320 atomic_set(&match->rr_cur, 0);
1321 INIT_LIST_HEAD(&match->list);
1322 spin_lock_init(&match->lock);
1323 atomic_set(&match->sk_ref, 0);
1324 match->prot_hook.type = po->prot_hook.type;
1325 match->prot_hook.dev = po->prot_hook.dev;
1326 match->prot_hook.func = packet_rcv_fanout;
1327 match->prot_hook.af_packet_priv = match;
1328 dev_add_pack(&match->prot_hook);
1329 list_add(&match->list, &fanout_list);
1330 }
1331 err = -EINVAL;
1332 if (match->type == type &&
1333 match->prot_hook.type == po->prot_hook.type &&
1334 match->prot_hook.dev == po->prot_hook.dev) {
1335 err = -ENOSPC;
1336 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1337 __dev_remove_pack(&po->prot_hook);
1338 po->fanout = match;
1339 atomic_inc(&match->sk_ref);
1340 __fanout_link(sk, po);
1341 err = 0;
1342 }
1343 }
1344 out:
1345 mutex_unlock(&fanout_mutex);
1346 return err;
1347 }
1348
1349 static void fanout_release(struct sock *sk)
1350 {
1351 struct packet_sock *po = pkt_sk(sk);
1352 struct packet_fanout *f;
1353
1354 f = po->fanout;
1355 if (!f)
1356 return;
1357
1358 po->fanout = NULL;
1359
1360 mutex_lock(&fanout_mutex);
1361 if (atomic_dec_and_test(&f->sk_ref)) {
1362 list_del(&f->list);
1363 dev_remove_pack(&f->prot_hook);
1364 kfree(f);
1365 }
1366 mutex_unlock(&fanout_mutex);
1367 }
1368
1369 static const struct proto_ops packet_ops;
1370
1371 static const struct proto_ops packet_ops_spkt;
1372
1373 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1374 struct packet_type *pt, struct net_device *orig_dev)
1375 {
1376 struct sock *sk;
1377 struct sockaddr_pkt *spkt;
1378
1379 /*
1380 * When we registered the protocol we saved the socket in the data
1381 * field for just this event.
1382 */
1383
1384 sk = pt->af_packet_priv;
1385
1386 /*
1387 * Yank back the headers [hope the device set this
1388 * right or kerboom...]
1389 *
1390 * Incoming packets have ll header pulled,
1391 * push it back.
1392 *
1393 * For outgoing ones skb->data == skb_mac_header(skb)
1394 * so that this procedure is noop.
1395 */
1396
1397 if (skb->pkt_type == PACKET_LOOPBACK)
1398 goto out;
1399
1400 if (!net_eq(dev_net(dev), sock_net(sk)))
1401 goto out;
1402
1403 skb = skb_share_check(skb, GFP_ATOMIC);
1404 if (skb == NULL)
1405 goto oom;
1406
1407 /* drop any routing info */
1408 skb_dst_drop(skb);
1409
1410 /* drop conntrack reference */
1411 nf_reset(skb);
1412
1413 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1414
1415 skb_push(skb, skb->data - skb_mac_header(skb));
1416
1417 /*
1418 * The SOCK_PACKET socket receives _all_ frames.
1419 */
1420
1421 spkt->spkt_family = dev->type;
1422 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1423 spkt->spkt_protocol = skb->protocol;
1424
1425 /*
1426 * Charge the memory to the socket. This is done specifically
1427 * to prevent sockets using all the memory up.
1428 */
1429
1430 if (sock_queue_rcv_skb(sk, skb) == 0)
1431 return 0;
1432
1433 out:
1434 kfree_skb(skb);
1435 oom:
1436 return 0;
1437 }
1438
1439
1440 /*
1441 * Output a raw packet to a device layer. This bypasses all the other
1442 * protocol layers and you must therefore supply it with a complete frame
1443 */
1444
1445 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1446 struct msghdr *msg, size_t len)
1447 {
1448 struct sock *sk = sock->sk;
1449 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1450 struct sk_buff *skb = NULL;
1451 struct net_device *dev;
1452 __be16 proto = 0;
1453 int err;
1454 int extra_len = 0;
1455
1456 /*
1457 * Get and verify the address.
1458 */
1459
1460 if (saddr) {
1461 if (msg->msg_namelen < sizeof(struct sockaddr))
1462 return -EINVAL;
1463 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1464 proto = saddr->spkt_protocol;
1465 } else
1466 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1467
1468 /*
1469 * Find the device first to size check it
1470 */
1471
1472 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1473 retry:
1474 rcu_read_lock();
1475 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1476 err = -ENODEV;
1477 if (dev == NULL)
1478 goto out_unlock;
1479
1480 err = -ENETDOWN;
1481 if (!(dev->flags & IFF_UP))
1482 goto out_unlock;
1483
1484 /*
1485 * You may not queue a frame bigger than the mtu. This is the lowest level
1486 * raw protocol and you must do your own fragmentation at this level.
1487 */
1488
1489 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1490 if (!netif_supports_nofcs(dev)) {
1491 err = -EPROTONOSUPPORT;
1492 goto out_unlock;
1493 }
1494 extra_len = 4; /* We're doing our own CRC */
1495 }
1496
1497 err = -EMSGSIZE;
1498 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1499 goto out_unlock;
1500
1501 if (!skb) {
1502 size_t reserved = LL_RESERVED_SPACE(dev);
1503 int tlen = dev->needed_tailroom;
1504 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1505
1506 rcu_read_unlock();
1507 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1508 if (skb == NULL)
1509 return -ENOBUFS;
1510 /* FIXME: Save some space for broken drivers that write a hard
1511 * header at transmission time by themselves. PPP is the notable
1512 * one here. This should really be fixed at the driver level.
1513 */
1514 skb_reserve(skb, reserved);
1515 skb_reset_network_header(skb);
1516
1517 /* Try to align data part correctly */
1518 if (hhlen) {
1519 skb->data -= hhlen;
1520 skb->tail -= hhlen;
1521 if (len < hhlen)
1522 skb_reset_network_header(skb);
1523 }
1524 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1525 if (err)
1526 goto out_free;
1527 goto retry;
1528 }
1529
1530 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1531 /* Earlier code assumed this would be a VLAN pkt,
1532 * double-check this now that we have the actual
1533 * packet in hand.
1534 */
1535 struct ethhdr *ehdr;
1536 skb_reset_mac_header(skb);
1537 ehdr = eth_hdr(skb);
1538 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1539 err = -EMSGSIZE;
1540 goto out_unlock;
1541 }
1542 }
1543
1544 skb->protocol = proto;
1545 skb->dev = dev;
1546 skb->priority = sk->sk_priority;
1547 skb->mark = sk->sk_mark;
1548 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1549 if (err < 0)
1550 goto out_unlock;
1551
1552 if (unlikely(extra_len == 4))
1553 skb->no_fcs = 1;
1554
1555 dev_queue_xmit(skb);
1556 rcu_read_unlock();
1557 return len;
1558
1559 out_unlock:
1560 rcu_read_unlock();
1561 out_free:
1562 kfree_skb(skb);
1563 return err;
1564 }
1565
1566 static unsigned int run_filter(const struct sk_buff *skb,
1567 const struct sock *sk,
1568 unsigned int res)
1569 {
1570 struct sk_filter *filter;
1571
1572 rcu_read_lock();
1573 filter = rcu_dereference(sk->sk_filter);
1574 if (filter != NULL)
1575 res = SK_RUN_FILTER(filter, skb);
1576 rcu_read_unlock();
1577
1578 return res;
1579 }
1580
1581 /*
1582 * This function makes lazy skb cloning in hope that most of packets
1583 * are discarded by BPF.
1584 *
1585 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1586 * and skb->cb are mangled. It works because (and until) packets
1587 * falling here are owned by current CPU. Output packets are cloned
1588 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1589 * sequencially, so that if we return skb to original state on exit,
1590 * we will not harm anyone.
1591 */
1592
1593 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1594 struct packet_type *pt, struct net_device *orig_dev)
1595 {
1596 struct sock *sk;
1597 struct sockaddr_ll *sll;
1598 struct packet_sock *po;
1599 u8 *skb_head = skb->data;
1600 int skb_len = skb->len;
1601 unsigned int snaplen, res;
1602
1603 if (skb->pkt_type == PACKET_LOOPBACK)
1604 goto drop;
1605
1606 sk = pt->af_packet_priv;
1607 po = pkt_sk(sk);
1608
1609 if (!net_eq(dev_net(dev), sock_net(sk)))
1610 goto drop;
1611
1612 skb->dev = dev;
1613
1614 if (dev->header_ops) {
1615 /* The device has an explicit notion of ll header,
1616 * exported to higher levels.
1617 *
1618 * Otherwise, the device hides details of its frame
1619 * structure, so that corresponding packet head is
1620 * never delivered to user.
1621 */
1622 if (sk->sk_type != SOCK_DGRAM)
1623 skb_push(skb, skb->data - skb_mac_header(skb));
1624 else if (skb->pkt_type == PACKET_OUTGOING) {
1625 /* Special case: outgoing packets have ll header at head */
1626 skb_pull(skb, skb_network_offset(skb));
1627 }
1628 }
1629
1630 snaplen = skb->len;
1631
1632 res = run_filter(skb, sk, snaplen);
1633 if (!res)
1634 goto drop_n_restore;
1635 if (snaplen > res)
1636 snaplen = res;
1637
1638 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1639 goto drop_n_acct;
1640
1641 if (skb_shared(skb)) {
1642 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1643 if (nskb == NULL)
1644 goto drop_n_acct;
1645
1646 if (skb_head != skb->data) {
1647 skb->data = skb_head;
1648 skb->len = skb_len;
1649 }
1650 consume_skb(skb);
1651 skb = nskb;
1652 }
1653
1654 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1655 sizeof(skb->cb));
1656
1657 sll = &PACKET_SKB_CB(skb)->sa.ll;
1658 sll->sll_family = AF_PACKET;
1659 sll->sll_hatype = dev->type;
1660 sll->sll_protocol = skb->protocol;
1661 sll->sll_pkttype = skb->pkt_type;
1662 if (unlikely(po->origdev))
1663 sll->sll_ifindex = orig_dev->ifindex;
1664 else
1665 sll->sll_ifindex = dev->ifindex;
1666
1667 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1668
1669 PACKET_SKB_CB(skb)->origlen = skb->len;
1670
1671 if (pskb_trim(skb, snaplen))
1672 goto drop_n_acct;
1673
1674 skb_set_owner_r(skb, sk);
1675 skb->dev = NULL;
1676 skb_dst_drop(skb);
1677
1678 /* drop conntrack reference */
1679 nf_reset(skb);
1680
1681 spin_lock(&sk->sk_receive_queue.lock);
1682 po->stats.tp_packets++;
1683 skb->dropcount = atomic_read(&sk->sk_drops);
1684 __skb_queue_tail(&sk->sk_receive_queue, skb);
1685 spin_unlock(&sk->sk_receive_queue.lock);
1686 sk->sk_data_ready(sk, skb->len);
1687 return 0;
1688
1689 drop_n_acct:
1690 spin_lock(&sk->sk_receive_queue.lock);
1691 po->stats.tp_drops++;
1692 atomic_inc(&sk->sk_drops);
1693 spin_unlock(&sk->sk_receive_queue.lock);
1694
1695 drop_n_restore:
1696 if (skb_head != skb->data && skb_shared(skb)) {
1697 skb->data = skb_head;
1698 skb->len = skb_len;
1699 }
1700 drop:
1701 consume_skb(skb);
1702 return 0;
1703 }
1704
1705 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1706 struct packet_type *pt, struct net_device *orig_dev)
1707 {
1708 struct sock *sk;
1709 struct packet_sock *po;
1710 struct sockaddr_ll *sll;
1711 union {
1712 struct tpacket_hdr *h1;
1713 struct tpacket2_hdr *h2;
1714 struct tpacket3_hdr *h3;
1715 void *raw;
1716 } h;
1717 u8 *skb_head = skb->data;
1718 int skb_len = skb->len;
1719 unsigned int snaplen, res;
1720 unsigned long status = TP_STATUS_USER;
1721 unsigned short macoff, netoff, hdrlen;
1722 struct sk_buff *copy_skb = NULL;
1723 struct timeval tv;
1724 struct timespec ts;
1725 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1726
1727 if (skb->pkt_type == PACKET_LOOPBACK)
1728 goto drop;
1729
1730 sk = pt->af_packet_priv;
1731 po = pkt_sk(sk);
1732
1733 if (!net_eq(dev_net(dev), sock_net(sk)))
1734 goto drop;
1735
1736 if (dev->header_ops) {
1737 if (sk->sk_type != SOCK_DGRAM)
1738 skb_push(skb, skb->data - skb_mac_header(skb));
1739 else if (skb->pkt_type == PACKET_OUTGOING) {
1740 /* Special case: outgoing packets have ll header at head */
1741 skb_pull(skb, skb_network_offset(skb));
1742 }
1743 }
1744
1745 if (skb->ip_summed == CHECKSUM_PARTIAL)
1746 status |= TP_STATUS_CSUMNOTREADY;
1747
1748 snaplen = skb->len;
1749
1750 res = run_filter(skb, sk, snaplen);
1751 if (!res)
1752 goto drop_n_restore;
1753 if (snaplen > res)
1754 snaplen = res;
1755
1756 if (sk->sk_type == SOCK_DGRAM) {
1757 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1758 po->tp_reserve;
1759 } else {
1760 unsigned int maclen = skb_network_offset(skb);
1761 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1762 (maclen < 16 ? 16 : maclen)) +
1763 po->tp_reserve;
1764 macoff = netoff - maclen;
1765 }
1766 if (po->tp_version <= TPACKET_V2) {
1767 if (macoff + snaplen > po->rx_ring.frame_size) {
1768 if (po->copy_thresh &&
1769 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1770 if (skb_shared(skb)) {
1771 copy_skb = skb_clone(skb, GFP_ATOMIC);
1772 } else {
1773 copy_skb = skb_get(skb);
1774 skb_head = skb->data;
1775 }
1776 if (copy_skb)
1777 skb_set_owner_r(copy_skb, sk);
1778 }
1779 snaplen = po->rx_ring.frame_size - macoff;
1780 if ((int)snaplen < 0)
1781 snaplen = 0;
1782 }
1783 }
1784 spin_lock(&sk->sk_receive_queue.lock);
1785 h.raw = packet_current_rx_frame(po, skb,
1786 TP_STATUS_KERNEL, (macoff+snaplen));
1787 if (!h.raw)
1788 goto ring_is_full;
1789 if (po->tp_version <= TPACKET_V2) {
1790 packet_increment_rx_head(po, &po->rx_ring);
1791 /*
1792 * LOSING will be reported till you read the stats,
1793 * because it's COR - Clear On Read.
1794 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1795 * at packet level.
1796 */
1797 if (po->stats.tp_drops)
1798 status |= TP_STATUS_LOSING;
1799 }
1800 po->stats.tp_packets++;
1801 if (copy_skb) {
1802 status |= TP_STATUS_COPY;
1803 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1804 }
1805 spin_unlock(&sk->sk_receive_queue.lock);
1806
1807 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1808
1809 switch (po->tp_version) {
1810 case TPACKET_V1:
1811 h.h1->tp_len = skb->len;
1812 h.h1->tp_snaplen = snaplen;
1813 h.h1->tp_mac = macoff;
1814 h.h1->tp_net = netoff;
1815 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1816 && shhwtstamps->syststamp.tv64)
1817 tv = ktime_to_timeval(shhwtstamps->syststamp);
1818 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1819 && shhwtstamps->hwtstamp.tv64)
1820 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1821 else if (skb->tstamp.tv64)
1822 tv = ktime_to_timeval(skb->tstamp);
1823 else
1824 do_gettimeofday(&tv);
1825 h.h1->tp_sec = tv.tv_sec;
1826 h.h1->tp_usec = tv.tv_usec;
1827 hdrlen = sizeof(*h.h1);
1828 break;
1829 case TPACKET_V2:
1830 h.h2->tp_len = skb->len;
1831 h.h2->tp_snaplen = snaplen;
1832 h.h2->tp_mac = macoff;
1833 h.h2->tp_net = netoff;
1834 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1835 && shhwtstamps->syststamp.tv64)
1836 ts = ktime_to_timespec(shhwtstamps->syststamp);
1837 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1838 && shhwtstamps->hwtstamp.tv64)
1839 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1840 else if (skb->tstamp.tv64)
1841 ts = ktime_to_timespec(skb->tstamp);
1842 else
1843 getnstimeofday(&ts);
1844 h.h2->tp_sec = ts.tv_sec;
1845 h.h2->tp_nsec = ts.tv_nsec;
1846 if (vlan_tx_tag_present(skb)) {
1847 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1848 status |= TP_STATUS_VLAN_VALID;
1849 } else {
1850 h.h2->tp_vlan_tci = 0;
1851 }
1852 h.h2->tp_padding = 0;
1853 hdrlen = sizeof(*h.h2);
1854 break;
1855 case TPACKET_V3:
1856 /* tp_nxt_offset,vlan are already populated above.
1857 * So DONT clear those fields here
1858 */
1859 h.h3->tp_status |= status;
1860 h.h3->tp_len = skb->len;
1861 h.h3->tp_snaplen = snaplen;
1862 h.h3->tp_mac = macoff;
1863 h.h3->tp_net = netoff;
1864 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1865 && shhwtstamps->syststamp.tv64)
1866 ts = ktime_to_timespec(shhwtstamps->syststamp);
1867 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1868 && shhwtstamps->hwtstamp.tv64)
1869 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1870 else if (skb->tstamp.tv64)
1871 ts = ktime_to_timespec(skb->tstamp);
1872 else
1873 getnstimeofday(&ts);
1874 h.h3->tp_sec = ts.tv_sec;
1875 h.h3->tp_nsec = ts.tv_nsec;
1876 hdrlen = sizeof(*h.h3);
1877 break;
1878 default:
1879 BUG();
1880 }
1881
1882 sll = h.raw + TPACKET_ALIGN(hdrlen);
1883 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1884 sll->sll_family = AF_PACKET;
1885 sll->sll_hatype = dev->type;
1886 sll->sll_protocol = skb->protocol;
1887 sll->sll_pkttype = skb->pkt_type;
1888 if (unlikely(po->origdev))
1889 sll->sll_ifindex = orig_dev->ifindex;
1890 else
1891 sll->sll_ifindex = dev->ifindex;
1892
1893 smp_mb();
1894 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1895 {
1896 u8 *start, *end;
1897
1898 if (po->tp_version <= TPACKET_V2) {
1899 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1900 + macoff + snaplen);
1901 for (start = h.raw; start < end; start += PAGE_SIZE)
1902 flush_dcache_page(pgv_to_page(start));
1903 }
1904 smp_wmb();
1905 }
1906 #endif
1907 if (po->tp_version <= TPACKET_V2)
1908 __packet_set_status(po, h.raw, status);
1909 else
1910 prb_clear_blk_fill_status(&po->rx_ring);
1911
1912 sk->sk_data_ready(sk, 0);
1913
1914 drop_n_restore:
1915 if (skb_head != skb->data && skb_shared(skb)) {
1916 skb->data = skb_head;
1917 skb->len = skb_len;
1918 }
1919 drop:
1920 kfree_skb(skb);
1921 return 0;
1922
1923 ring_is_full:
1924 po->stats.tp_drops++;
1925 spin_unlock(&sk->sk_receive_queue.lock);
1926
1927 sk->sk_data_ready(sk, 0);
1928 kfree_skb(copy_skb);
1929 goto drop_n_restore;
1930 }
1931
1932 static void tpacket_destruct_skb(struct sk_buff *skb)
1933 {
1934 struct packet_sock *po = pkt_sk(skb->sk);
1935 void *ph;
1936
1937 if (likely(po->tx_ring.pg_vec)) {
1938 ph = skb_shinfo(skb)->destructor_arg;
1939 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
1940 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1941 atomic_dec(&po->tx_ring.pending);
1942 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1943 }
1944
1945 sock_wfree(skb);
1946 }
1947
1948 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1949 void *frame, struct net_device *dev, int size_max,
1950 __be16 proto, unsigned char *addr, int hlen)
1951 {
1952 union {
1953 struct tpacket_hdr *h1;
1954 struct tpacket2_hdr *h2;
1955 void *raw;
1956 } ph;
1957 int to_write, offset, len, tp_len, nr_frags, len_max;
1958 struct socket *sock = po->sk.sk_socket;
1959 struct page *page;
1960 void *data;
1961 int err;
1962
1963 ph.raw = frame;
1964
1965 skb->protocol = proto;
1966 skb->dev = dev;
1967 skb->priority = po->sk.sk_priority;
1968 skb->mark = po->sk.sk_mark;
1969 skb_shinfo(skb)->destructor_arg = ph.raw;
1970
1971 switch (po->tp_version) {
1972 case TPACKET_V2:
1973 tp_len = ph.h2->tp_len;
1974 break;
1975 default:
1976 tp_len = ph.h1->tp_len;
1977 break;
1978 }
1979 if (unlikely(tp_len > size_max)) {
1980 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1981 return -EMSGSIZE;
1982 }
1983
1984 skb_reserve(skb, hlen);
1985 skb_reset_network_header(skb);
1986
1987 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1988 to_write = tp_len;
1989
1990 if (sock->type == SOCK_DGRAM) {
1991 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1992 NULL, tp_len);
1993 if (unlikely(err < 0))
1994 return -EINVAL;
1995 } else if (dev->hard_header_len) {
1996 /* net device doesn't like empty head */
1997 if (unlikely(tp_len <= dev->hard_header_len)) {
1998 pr_err("packet size is too short (%d < %d)\n",
1999 tp_len, dev->hard_header_len);
2000 return -EINVAL;
2001 }
2002
2003 skb_push(skb, dev->hard_header_len);
2004 err = skb_store_bits(skb, 0, data,
2005 dev->hard_header_len);
2006 if (unlikely(err))
2007 return err;
2008
2009 data += dev->hard_header_len;
2010 to_write -= dev->hard_header_len;
2011 }
2012
2013 err = -EFAULT;
2014 offset = offset_in_page(data);
2015 len_max = PAGE_SIZE - offset;
2016 len = ((to_write > len_max) ? len_max : to_write);
2017
2018 skb->data_len = to_write;
2019 skb->len += to_write;
2020 skb->truesize += to_write;
2021 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2022
2023 while (likely(to_write)) {
2024 nr_frags = skb_shinfo(skb)->nr_frags;
2025
2026 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2027 pr_err("Packet exceed the number of skb frags(%lu)\n",
2028 MAX_SKB_FRAGS);
2029 return -EFAULT;
2030 }
2031
2032 page = pgv_to_page(data);
2033 data += len;
2034 flush_dcache_page(page);
2035 get_page(page);
2036 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2037 to_write -= len;
2038 offset = 0;
2039 len_max = PAGE_SIZE;
2040 len = ((to_write > len_max) ? len_max : to_write);
2041 }
2042
2043 return tp_len;
2044 }
2045
2046 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2047 {
2048 struct sk_buff *skb;
2049 struct net_device *dev;
2050 __be16 proto;
2051 bool need_rls_dev = false;
2052 int err, reserve = 0;
2053 void *ph;
2054 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2055 int tp_len, size_max;
2056 unsigned char *addr;
2057 int len_sum = 0;
2058 int status = 0;
2059 int hlen, tlen;
2060
2061 mutex_lock(&po->pg_vec_lock);
2062
2063 err = -EBUSY;
2064 if (saddr == NULL) {
2065 dev = po->prot_hook.dev;
2066 proto = po->num;
2067 addr = NULL;
2068 } else {
2069 err = -EINVAL;
2070 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2071 goto out;
2072 if (msg->msg_namelen < (saddr->sll_halen
2073 + offsetof(struct sockaddr_ll,
2074 sll_addr)))
2075 goto out;
2076 proto = saddr->sll_protocol;
2077 addr = saddr->sll_addr;
2078 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2079 need_rls_dev = true;
2080 }
2081
2082 err = -ENXIO;
2083 if (unlikely(dev == NULL))
2084 goto out;
2085
2086 reserve = dev->hard_header_len;
2087
2088 err = -ENETDOWN;
2089 if (unlikely(!(dev->flags & IFF_UP)))
2090 goto out_put;
2091
2092 size_max = po->tx_ring.frame_size
2093 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2094
2095 if (size_max > dev->mtu + reserve)
2096 size_max = dev->mtu + reserve;
2097
2098 do {
2099 ph = packet_current_frame(po, &po->tx_ring,
2100 TP_STATUS_SEND_REQUEST);
2101
2102 if (unlikely(ph == NULL)) {
2103 schedule();
2104 continue;
2105 }
2106
2107 status = TP_STATUS_SEND_REQUEST;
2108 hlen = LL_RESERVED_SPACE(dev);
2109 tlen = dev->needed_tailroom;
2110 skb = sock_alloc_send_skb(&po->sk,
2111 hlen + tlen + sizeof(struct sockaddr_ll),
2112 0, &err);
2113
2114 if (unlikely(skb == NULL))
2115 goto out_status;
2116
2117 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2118 addr, hlen);
2119
2120 if (unlikely(tp_len < 0)) {
2121 if (po->tp_loss) {
2122 __packet_set_status(po, ph,
2123 TP_STATUS_AVAILABLE);
2124 packet_increment_head(&po->tx_ring);
2125 kfree_skb(skb);
2126 continue;
2127 } else {
2128 status = TP_STATUS_WRONG_FORMAT;
2129 err = tp_len;
2130 goto out_status;
2131 }
2132 }
2133
2134 skb->destructor = tpacket_destruct_skb;
2135 __packet_set_status(po, ph, TP_STATUS_SENDING);
2136 atomic_inc(&po->tx_ring.pending);
2137
2138 status = TP_STATUS_SEND_REQUEST;
2139 err = dev_queue_xmit(skb);
2140 if (unlikely(err > 0)) {
2141 err = net_xmit_errno(err);
2142 if (err && __packet_get_status(po, ph) ==
2143 TP_STATUS_AVAILABLE) {
2144 /* skb was destructed already */
2145 skb = NULL;
2146 goto out_status;
2147 }
2148 /*
2149 * skb was dropped but not destructed yet;
2150 * let's treat it like congestion or err < 0
2151 */
2152 err = 0;
2153 }
2154 packet_increment_head(&po->tx_ring);
2155 len_sum += tp_len;
2156 } while (likely((ph != NULL) ||
2157 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2158 (atomic_read(&po->tx_ring.pending))))
2159 );
2160
2161 err = len_sum;
2162 goto out_put;
2163
2164 out_status:
2165 __packet_set_status(po, ph, status);
2166 kfree_skb(skb);
2167 out_put:
2168 if (need_rls_dev)
2169 dev_put(dev);
2170 out:
2171 mutex_unlock(&po->pg_vec_lock);
2172 return err;
2173 }
2174
2175 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2176 size_t reserve, size_t len,
2177 size_t linear, int noblock,
2178 int *err)
2179 {
2180 struct sk_buff *skb;
2181
2182 /* Under a page? Don't bother with paged skb. */
2183 if (prepad + len < PAGE_SIZE || !linear)
2184 linear = len;
2185
2186 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2187 err);
2188 if (!skb)
2189 return NULL;
2190
2191 skb_reserve(skb, reserve);
2192 skb_put(skb, linear);
2193 skb->data_len = len - linear;
2194 skb->len += len - linear;
2195
2196 return skb;
2197 }
2198
2199 static int packet_snd(struct socket *sock,
2200 struct msghdr *msg, size_t len)
2201 {
2202 struct sock *sk = sock->sk;
2203 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2204 struct sk_buff *skb;
2205 struct net_device *dev;
2206 __be16 proto;
2207 bool need_rls_dev = false;
2208 unsigned char *addr;
2209 int err, reserve = 0;
2210 struct virtio_net_hdr vnet_hdr = { 0 };
2211 int offset = 0;
2212 int vnet_hdr_len;
2213 struct packet_sock *po = pkt_sk(sk);
2214 unsigned short gso_type = 0;
2215 int hlen, tlen;
2216 int extra_len = 0;
2217
2218 /*
2219 * Get and verify the address.
2220 */
2221
2222 if (saddr == NULL) {
2223 dev = po->prot_hook.dev;
2224 proto = po->num;
2225 addr = NULL;
2226 } else {
2227 err = -EINVAL;
2228 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2229 goto out;
2230 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2231 goto out;
2232 proto = saddr->sll_protocol;
2233 addr = saddr->sll_addr;
2234 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2235 need_rls_dev = true;
2236 }
2237
2238 err = -ENXIO;
2239 if (dev == NULL)
2240 goto out_unlock;
2241 if (sock->type == SOCK_RAW)
2242 reserve = dev->hard_header_len;
2243
2244 err = -ENETDOWN;
2245 if (!(dev->flags & IFF_UP))
2246 goto out_unlock;
2247
2248 if (po->has_vnet_hdr) {
2249 vnet_hdr_len = sizeof(vnet_hdr);
2250
2251 err = -EINVAL;
2252 if (len < vnet_hdr_len)
2253 goto out_unlock;
2254
2255 len -= vnet_hdr_len;
2256
2257 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2258 vnet_hdr_len);
2259 if (err < 0)
2260 goto out_unlock;
2261
2262 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2263 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2264 vnet_hdr.hdr_len))
2265 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2266 vnet_hdr.csum_offset + 2;
2267
2268 err = -EINVAL;
2269 if (vnet_hdr.hdr_len > len)
2270 goto out_unlock;
2271
2272 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2273 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2274 case VIRTIO_NET_HDR_GSO_TCPV4:
2275 gso_type = SKB_GSO_TCPV4;
2276 break;
2277 case VIRTIO_NET_HDR_GSO_TCPV6:
2278 gso_type = SKB_GSO_TCPV6;
2279 break;
2280 case VIRTIO_NET_HDR_GSO_UDP:
2281 gso_type = SKB_GSO_UDP;
2282 break;
2283 default:
2284 goto out_unlock;
2285 }
2286
2287 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2288 gso_type |= SKB_GSO_TCP_ECN;
2289
2290 if (vnet_hdr.gso_size == 0)
2291 goto out_unlock;
2292
2293 }
2294 }
2295
2296 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2297 if (!netif_supports_nofcs(dev)) {
2298 err = -EPROTONOSUPPORT;
2299 goto out_unlock;
2300 }
2301 extra_len = 4; /* We're doing our own CRC */
2302 }
2303
2304 err = -EMSGSIZE;
2305 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2306 goto out_unlock;
2307
2308 err = -ENOBUFS;
2309 hlen = LL_RESERVED_SPACE(dev);
2310 tlen = dev->needed_tailroom;
2311 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2312 msg->msg_flags & MSG_DONTWAIT, &err);
2313 if (skb == NULL)
2314 goto out_unlock;
2315
2316 skb_set_network_header(skb, reserve);
2317
2318 err = -EINVAL;
2319 if (sock->type == SOCK_DGRAM &&
2320 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2321 goto out_free;
2322
2323 /* Returns -EFAULT on error */
2324 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2325 if (err)
2326 goto out_free;
2327 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2328 if (err < 0)
2329 goto out_free;
2330
2331 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2332 /* Earlier code assumed this would be a VLAN pkt,
2333 * double-check this now that we have the actual
2334 * packet in hand.
2335 */
2336 struct ethhdr *ehdr;
2337 skb_reset_mac_header(skb);
2338 ehdr = eth_hdr(skb);
2339 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2340 err = -EMSGSIZE;
2341 goto out_free;
2342 }
2343 }
2344
2345 skb->protocol = proto;
2346 skb->dev = dev;
2347 skb->priority = sk->sk_priority;
2348 skb->mark = sk->sk_mark;
2349
2350 if (po->has_vnet_hdr) {
2351 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2352 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2353 vnet_hdr.csum_offset)) {
2354 err = -EINVAL;
2355 goto out_free;
2356 }
2357 }
2358
2359 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2360 skb_shinfo(skb)->gso_type = gso_type;
2361
2362 /* Header must be checked, and gso_segs computed. */
2363 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2364 skb_shinfo(skb)->gso_segs = 0;
2365
2366 len += vnet_hdr_len;
2367 }
2368
2369 if (unlikely(extra_len == 4))
2370 skb->no_fcs = 1;
2371
2372 /*
2373 * Now send it
2374 */
2375
2376 err = dev_queue_xmit(skb);
2377 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2378 goto out_unlock;
2379
2380 if (need_rls_dev)
2381 dev_put(dev);
2382
2383 return len;
2384
2385 out_free:
2386 kfree_skb(skb);
2387 out_unlock:
2388 if (dev && need_rls_dev)
2389 dev_put(dev);
2390 out:
2391 return err;
2392 }
2393
2394 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2395 struct msghdr *msg, size_t len)
2396 {
2397 struct sock *sk = sock->sk;
2398 struct packet_sock *po = pkt_sk(sk);
2399 if (po->tx_ring.pg_vec)
2400 return tpacket_snd(po, msg);
2401 else
2402 return packet_snd(sock, msg, len);
2403 }
2404
2405 /*
2406 * Close a PACKET socket. This is fairly simple. We immediately go
2407 * to 'closed' state and remove our protocol entry in the device list.
2408 */
2409
2410 static int packet_release(struct socket *sock)
2411 {
2412 struct sock *sk = sock->sk;
2413 struct packet_sock *po;
2414 struct net *net;
2415 union tpacket_req_u req_u;
2416
2417 if (!sk)
2418 return 0;
2419
2420 net = sock_net(sk);
2421 po = pkt_sk(sk);
2422
2423 spin_lock_bh(&net->packet.sklist_lock);
2424 sk_del_node_init_rcu(sk);
2425 sock_prot_inuse_add(net, sk->sk_prot, -1);
2426 spin_unlock_bh(&net->packet.sklist_lock);
2427
2428 spin_lock(&po->bind_lock);
2429 unregister_prot_hook(sk, false);
2430 if (po->prot_hook.dev) {
2431 dev_put(po->prot_hook.dev);
2432 po->prot_hook.dev = NULL;
2433 }
2434 spin_unlock(&po->bind_lock);
2435
2436 packet_flush_mclist(sk);
2437
2438 memset(&req_u, 0, sizeof(req_u));
2439
2440 if (po->rx_ring.pg_vec)
2441 packet_set_ring(sk, &req_u, 1, 0);
2442
2443 if (po->tx_ring.pg_vec)
2444 packet_set_ring(sk, &req_u, 1, 1);
2445
2446 fanout_release(sk);
2447
2448 synchronize_net();
2449 /*
2450 * Now the socket is dead. No more input will appear.
2451 */
2452 sock_orphan(sk);
2453 sock->sk = NULL;
2454
2455 /* Purge queues */
2456
2457 skb_queue_purge(&sk->sk_receive_queue);
2458 sk_refcnt_debug_release(sk);
2459
2460 sock_put(sk);
2461 return 0;
2462 }
2463
2464 /*
2465 * Attach a packet hook.
2466 */
2467
2468 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2469 {
2470 struct packet_sock *po = pkt_sk(sk);
2471
2472 if (po->fanout) {
2473 if (dev)
2474 dev_put(dev);
2475
2476 return -EINVAL;
2477 }
2478
2479 lock_sock(sk);
2480
2481 spin_lock(&po->bind_lock);
2482 unregister_prot_hook(sk, true);
2483 po->num = protocol;
2484 po->prot_hook.type = protocol;
2485 if (po->prot_hook.dev)
2486 dev_put(po->prot_hook.dev);
2487 po->prot_hook.dev = dev;
2488
2489 po->ifindex = dev ? dev->ifindex : 0;
2490
2491 if (protocol == 0)
2492 goto out_unlock;
2493
2494 if (!dev || (dev->flags & IFF_UP)) {
2495 register_prot_hook(sk);
2496 } else {
2497 sk->sk_err = ENETDOWN;
2498 if (!sock_flag(sk, SOCK_DEAD))
2499 sk->sk_error_report(sk);
2500 }
2501
2502 out_unlock:
2503 spin_unlock(&po->bind_lock);
2504 release_sock(sk);
2505 return 0;
2506 }
2507
2508 /*
2509 * Bind a packet socket to a device
2510 */
2511
2512 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2513 int addr_len)
2514 {
2515 struct sock *sk = sock->sk;
2516 char name[15];
2517 struct net_device *dev;
2518 int err = -ENODEV;
2519
2520 /*
2521 * Check legality
2522 */
2523
2524 if (addr_len != sizeof(struct sockaddr))
2525 return -EINVAL;
2526 strlcpy(name, uaddr->sa_data, sizeof(name));
2527
2528 dev = dev_get_by_name(sock_net(sk), name);
2529 if (dev)
2530 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2531 return err;
2532 }
2533
2534 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2535 {
2536 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2537 struct sock *sk = sock->sk;
2538 struct net_device *dev = NULL;
2539 int err;
2540
2541
2542 /*
2543 * Check legality
2544 */
2545
2546 if (addr_len < sizeof(struct sockaddr_ll))
2547 return -EINVAL;
2548 if (sll->sll_family != AF_PACKET)
2549 return -EINVAL;
2550
2551 if (sll->sll_ifindex) {
2552 err = -ENODEV;
2553 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2554 if (dev == NULL)
2555 goto out;
2556 }
2557 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2558
2559 out:
2560 return err;
2561 }
2562
2563 static struct proto packet_proto = {
2564 .name = "PACKET",
2565 .owner = THIS_MODULE,
2566 .obj_size = sizeof(struct packet_sock),
2567 };
2568
2569 /*
2570 * Create a packet of type SOCK_PACKET.
2571 */
2572
2573 static int packet_create(struct net *net, struct socket *sock, int protocol,
2574 int kern)
2575 {
2576 struct sock *sk;
2577 struct packet_sock *po;
2578 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2579 int err;
2580
2581 if (!capable(CAP_NET_RAW))
2582 return -EPERM;
2583 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2584 sock->type != SOCK_PACKET)
2585 return -ESOCKTNOSUPPORT;
2586
2587 sock->state = SS_UNCONNECTED;
2588
2589 err = -ENOBUFS;
2590 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2591 if (sk == NULL)
2592 goto out;
2593
2594 sock->ops = &packet_ops;
2595 if (sock->type == SOCK_PACKET)
2596 sock->ops = &packet_ops_spkt;
2597
2598 sock_init_data(sock, sk);
2599
2600 po = pkt_sk(sk);
2601 sk->sk_family = PF_PACKET;
2602 po->num = proto;
2603
2604 sk->sk_destruct = packet_sock_destruct;
2605 sk_refcnt_debug_inc(sk);
2606
2607 /*
2608 * Attach a protocol block
2609 */
2610
2611 spin_lock_init(&po->bind_lock);
2612 mutex_init(&po->pg_vec_lock);
2613 po->prot_hook.func = packet_rcv;
2614
2615 if (sock->type == SOCK_PACKET)
2616 po->prot_hook.func = packet_rcv_spkt;
2617
2618 po->prot_hook.af_packet_priv = sk;
2619
2620 if (proto) {
2621 po->prot_hook.type = proto;
2622 register_prot_hook(sk);
2623 }
2624
2625 spin_lock_bh(&net->packet.sklist_lock);
2626 sk_add_node_rcu(sk, &net->packet.sklist);
2627 sock_prot_inuse_add(net, &packet_proto, 1);
2628 spin_unlock_bh(&net->packet.sklist_lock);
2629
2630 return 0;
2631 out:
2632 return err;
2633 }
2634
2635 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2636 {
2637 struct sock_exterr_skb *serr;
2638 struct sk_buff *skb, *skb2;
2639 int copied, err;
2640
2641 err = -EAGAIN;
2642 skb = skb_dequeue(&sk->sk_error_queue);
2643 if (skb == NULL)
2644 goto out;
2645
2646 copied = skb->len;
2647 if (copied > len) {
2648 msg->msg_flags |= MSG_TRUNC;
2649 copied = len;
2650 }
2651 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2652 if (err)
2653 goto out_free_skb;
2654
2655 sock_recv_timestamp(msg, sk, skb);
2656
2657 serr = SKB_EXT_ERR(skb);
2658 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2659 sizeof(serr->ee), &serr->ee);
2660
2661 msg->msg_flags |= MSG_ERRQUEUE;
2662 err = copied;
2663
2664 /* Reset and regenerate socket error */
2665 spin_lock_bh(&sk->sk_error_queue.lock);
2666 sk->sk_err = 0;
2667 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2668 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2669 spin_unlock_bh(&sk->sk_error_queue.lock);
2670 sk->sk_error_report(sk);
2671 } else
2672 spin_unlock_bh(&sk->sk_error_queue.lock);
2673
2674 out_free_skb:
2675 kfree_skb(skb);
2676 out:
2677 return err;
2678 }
2679
2680 /*
2681 * Pull a packet from our receive queue and hand it to the user.
2682 * If necessary we block.
2683 */
2684
2685 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2686 struct msghdr *msg, size_t len, int flags)
2687 {
2688 struct sock *sk = sock->sk;
2689 struct sk_buff *skb;
2690 int copied, err;
2691 struct sockaddr_ll *sll;
2692 int vnet_hdr_len = 0;
2693
2694 err = -EINVAL;
2695 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2696 goto out;
2697
2698 #if 0
2699 /* What error should we return now? EUNATTACH? */
2700 if (pkt_sk(sk)->ifindex < 0)
2701 return -ENODEV;
2702 #endif
2703
2704 if (flags & MSG_ERRQUEUE) {
2705 err = packet_recv_error(sk, msg, len);
2706 goto out;
2707 }
2708
2709 /*
2710 * Call the generic datagram receiver. This handles all sorts
2711 * of horrible races and re-entrancy so we can forget about it
2712 * in the protocol layers.
2713 *
2714 * Now it will return ENETDOWN, if device have just gone down,
2715 * but then it will block.
2716 */
2717
2718 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2719
2720 /*
2721 * An error occurred so return it. Because skb_recv_datagram()
2722 * handles the blocking we don't see and worry about blocking
2723 * retries.
2724 */
2725
2726 if (skb == NULL)
2727 goto out;
2728
2729 if (pkt_sk(sk)->has_vnet_hdr) {
2730 struct virtio_net_hdr vnet_hdr = { 0 };
2731
2732 err = -EINVAL;
2733 vnet_hdr_len = sizeof(vnet_hdr);
2734 if (len < vnet_hdr_len)
2735 goto out_free;
2736
2737 len -= vnet_hdr_len;
2738
2739 if (skb_is_gso(skb)) {
2740 struct skb_shared_info *sinfo = skb_shinfo(skb);
2741
2742 /* This is a hint as to how much should be linear. */
2743 vnet_hdr.hdr_len = skb_headlen(skb);
2744 vnet_hdr.gso_size = sinfo->gso_size;
2745 if (sinfo->gso_type & SKB_GSO_TCPV4)
2746 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2747 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2748 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2749 else if (sinfo->gso_type & SKB_GSO_UDP)
2750 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2751 else if (sinfo->gso_type & SKB_GSO_FCOE)
2752 goto out_free;
2753 else
2754 BUG();
2755 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2756 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2757 } else
2758 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2759
2760 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2761 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2762 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2763 vnet_hdr.csum_offset = skb->csum_offset;
2764 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2765 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2766 } /* else everything is zero */
2767
2768 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2769 vnet_hdr_len);
2770 if (err < 0)
2771 goto out_free;
2772 }
2773
2774 /*
2775 * If the address length field is there to be filled in, we fill
2776 * it in now.
2777 */
2778
2779 sll = &PACKET_SKB_CB(skb)->sa.ll;
2780 if (sock->type == SOCK_PACKET)
2781 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2782 else
2783 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2784
2785 /*
2786 * You lose any data beyond the buffer you gave. If it worries a
2787 * user program they can ask the device for its MTU anyway.
2788 */
2789
2790 copied = skb->len;
2791 if (copied > len) {
2792 copied = len;
2793 msg->msg_flags |= MSG_TRUNC;
2794 }
2795
2796 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2797 if (err)
2798 goto out_free;
2799
2800 sock_recv_ts_and_drops(msg, sk, skb);
2801
2802 if (msg->msg_name)
2803 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2804 msg->msg_namelen);
2805
2806 if (pkt_sk(sk)->auxdata) {
2807 struct tpacket_auxdata aux;
2808
2809 aux.tp_status = TP_STATUS_USER;
2810 if (skb->ip_summed == CHECKSUM_PARTIAL)
2811 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2812 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2813 aux.tp_snaplen = skb->len;
2814 aux.tp_mac = 0;
2815 aux.tp_net = skb_network_offset(skb);
2816 if (vlan_tx_tag_present(skb)) {
2817 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2818 aux.tp_status |= TP_STATUS_VLAN_VALID;
2819 } else {
2820 aux.tp_vlan_tci = 0;
2821 }
2822 aux.tp_padding = 0;
2823 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2824 }
2825
2826 /*
2827 * Free or return the buffer as appropriate. Again this
2828 * hides all the races and re-entrancy issues from us.
2829 */
2830 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2831
2832 out_free:
2833 skb_free_datagram(sk, skb);
2834 out:
2835 return err;
2836 }
2837
2838 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2839 int *uaddr_len, int peer)
2840 {
2841 struct net_device *dev;
2842 struct sock *sk = sock->sk;
2843
2844 if (peer)
2845 return -EOPNOTSUPP;
2846
2847 uaddr->sa_family = AF_PACKET;
2848 rcu_read_lock();
2849 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2850 if (dev)
2851 strncpy(uaddr->sa_data, dev->name, 14);
2852 else
2853 memset(uaddr->sa_data, 0, 14);
2854 rcu_read_unlock();
2855 *uaddr_len = sizeof(*uaddr);
2856
2857 return 0;
2858 }
2859
2860 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2861 int *uaddr_len, int peer)
2862 {
2863 struct net_device *dev;
2864 struct sock *sk = sock->sk;
2865 struct packet_sock *po = pkt_sk(sk);
2866 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2867
2868 if (peer)
2869 return -EOPNOTSUPP;
2870
2871 sll->sll_family = AF_PACKET;
2872 sll->sll_ifindex = po->ifindex;
2873 sll->sll_protocol = po->num;
2874 sll->sll_pkttype = 0;
2875 rcu_read_lock();
2876 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2877 if (dev) {
2878 sll->sll_hatype = dev->type;
2879 sll->sll_halen = dev->addr_len;
2880 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2881 } else {
2882 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2883 sll->sll_halen = 0;
2884 }
2885 rcu_read_unlock();
2886 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2887
2888 return 0;
2889 }
2890
2891 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2892 int what)
2893 {
2894 switch (i->type) {
2895 case PACKET_MR_MULTICAST:
2896 if (i->alen != dev->addr_len)
2897 return -EINVAL;
2898 if (what > 0)
2899 return dev_mc_add(dev, i->addr);
2900 else
2901 return dev_mc_del(dev, i->addr);
2902 break;
2903 case PACKET_MR_PROMISC:
2904 return dev_set_promiscuity(dev, what);
2905 break;
2906 case PACKET_MR_ALLMULTI:
2907 return dev_set_allmulti(dev, what);
2908 break;
2909 case PACKET_MR_UNICAST:
2910 if (i->alen != dev->addr_len)
2911 return -EINVAL;
2912 if (what > 0)
2913 return dev_uc_add(dev, i->addr);
2914 else
2915 return dev_uc_del(dev, i->addr);
2916 break;
2917 default:
2918 break;
2919 }
2920 return 0;
2921 }
2922
2923 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2924 {
2925 for ( ; i; i = i->next) {
2926 if (i->ifindex == dev->ifindex)
2927 packet_dev_mc(dev, i, what);
2928 }
2929 }
2930
2931 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2932 {
2933 struct packet_sock *po = pkt_sk(sk);
2934 struct packet_mclist *ml, *i;
2935 struct net_device *dev;
2936 int err;
2937
2938 rtnl_lock();
2939
2940 err = -ENODEV;
2941 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2942 if (!dev)
2943 goto done;
2944
2945 err = -EINVAL;
2946 if (mreq->mr_alen > dev->addr_len)
2947 goto done;
2948
2949 err = -ENOBUFS;
2950 i = kmalloc(sizeof(*i), GFP_KERNEL);
2951 if (i == NULL)
2952 goto done;
2953
2954 err = 0;
2955 for (ml = po->mclist; ml; ml = ml->next) {
2956 if (ml->ifindex == mreq->mr_ifindex &&
2957 ml->type == mreq->mr_type &&
2958 ml->alen == mreq->mr_alen &&
2959 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2960 ml->count++;
2961 /* Free the new element ... */
2962 kfree(i);
2963 goto done;
2964 }
2965 }
2966
2967 i->type = mreq->mr_type;
2968 i->ifindex = mreq->mr_ifindex;
2969 i->alen = mreq->mr_alen;
2970 memcpy(i->addr, mreq->mr_address, i->alen);
2971 i->count = 1;
2972 i->next = po->mclist;
2973 po->mclist = i;
2974 err = packet_dev_mc(dev, i, 1);
2975 if (err) {
2976 po->mclist = i->next;
2977 kfree(i);
2978 }
2979
2980 done:
2981 rtnl_unlock();
2982 return err;
2983 }
2984
2985 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2986 {
2987 struct packet_mclist *ml, **mlp;
2988
2989 rtnl_lock();
2990
2991 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2992 if (ml->ifindex == mreq->mr_ifindex &&
2993 ml->type == mreq->mr_type &&
2994 ml->alen == mreq->mr_alen &&
2995 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2996 if (--ml->count == 0) {
2997 struct net_device *dev;
2998 *mlp = ml->next;
2999 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3000 if (dev)
3001 packet_dev_mc(dev, ml, -1);
3002 kfree(ml);
3003 }
3004 rtnl_unlock();
3005 return 0;
3006 }
3007 }
3008 rtnl_unlock();
3009 return -EADDRNOTAVAIL;
3010 }
3011
3012 static void packet_flush_mclist(struct sock *sk)
3013 {
3014 struct packet_sock *po = pkt_sk(sk);
3015 struct packet_mclist *ml;
3016
3017 if (!po->mclist)
3018 return;
3019
3020 rtnl_lock();
3021 while ((ml = po->mclist) != NULL) {
3022 struct net_device *dev;
3023
3024 po->mclist = ml->next;
3025 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3026 if (dev != NULL)
3027 packet_dev_mc(dev, ml, -1);
3028 kfree(ml);
3029 }
3030 rtnl_unlock();
3031 }
3032
3033 static int
3034 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3035 {
3036 struct sock *sk = sock->sk;
3037 struct packet_sock *po = pkt_sk(sk);
3038 int ret;
3039
3040 if (level != SOL_PACKET)
3041 return -ENOPROTOOPT;
3042
3043 switch (optname) {
3044 case PACKET_ADD_MEMBERSHIP:
3045 case PACKET_DROP_MEMBERSHIP:
3046 {
3047 struct packet_mreq_max mreq;
3048 int len = optlen;
3049 memset(&mreq, 0, sizeof(mreq));
3050 if (len < sizeof(struct packet_mreq))
3051 return -EINVAL;
3052 if (len > sizeof(mreq))
3053 len = sizeof(mreq);
3054 if (copy_from_user(&mreq, optval, len))
3055 return -EFAULT;
3056 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3057 return -EINVAL;
3058 if (optname == PACKET_ADD_MEMBERSHIP)
3059 ret = packet_mc_add(sk, &mreq);
3060 else
3061 ret = packet_mc_drop(sk, &mreq);
3062 return ret;
3063 }
3064
3065 case PACKET_RX_RING:
3066 case PACKET_TX_RING:
3067 {
3068 union tpacket_req_u req_u;
3069 int len;
3070
3071 switch (po->tp_version) {
3072 case TPACKET_V1:
3073 case TPACKET_V2:
3074 len = sizeof(req_u.req);
3075 break;
3076 case TPACKET_V3:
3077 default:
3078 len = sizeof(req_u.req3);
3079 break;
3080 }
3081 if (optlen < len)
3082 return -EINVAL;
3083 if (pkt_sk(sk)->has_vnet_hdr)
3084 return -EINVAL;
3085 if (copy_from_user(&req_u.req, optval, len))
3086 return -EFAULT;
3087 return packet_set_ring(sk, &req_u, 0,
3088 optname == PACKET_TX_RING);
3089 }
3090 case PACKET_COPY_THRESH:
3091 {
3092 int val;
3093
3094 if (optlen != sizeof(val))
3095 return -EINVAL;
3096 if (copy_from_user(&val, optval, sizeof(val)))
3097 return -EFAULT;
3098
3099 pkt_sk(sk)->copy_thresh = val;
3100 return 0;
3101 }
3102 case PACKET_VERSION:
3103 {
3104 int val;
3105
3106 if (optlen != sizeof(val))
3107 return -EINVAL;
3108 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3109 return -EBUSY;
3110 if (copy_from_user(&val, optval, sizeof(val)))
3111 return -EFAULT;
3112 switch (val) {
3113 case TPACKET_V1:
3114 case TPACKET_V2:
3115 case TPACKET_V3:
3116 po->tp_version = val;
3117 return 0;
3118 default:
3119 return -EINVAL;
3120 }
3121 }
3122 case PACKET_RESERVE:
3123 {
3124 unsigned int val;
3125
3126 if (optlen != sizeof(val))
3127 return -EINVAL;
3128 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3129 return -EBUSY;
3130 if (copy_from_user(&val, optval, sizeof(val)))
3131 return -EFAULT;
3132 po->tp_reserve = val;
3133 return 0;
3134 }
3135 case PACKET_LOSS:
3136 {
3137 unsigned int val;
3138
3139 if (optlen != sizeof(val))
3140 return -EINVAL;
3141 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3142 return -EBUSY;
3143 if (copy_from_user(&val, optval, sizeof(val)))
3144 return -EFAULT;
3145 po->tp_loss = !!val;
3146 return 0;
3147 }
3148 case PACKET_AUXDATA:
3149 {
3150 int val;
3151
3152 if (optlen < sizeof(val))
3153 return -EINVAL;
3154 if (copy_from_user(&val, optval, sizeof(val)))
3155 return -EFAULT;
3156
3157 po->auxdata = !!val;
3158 return 0;
3159 }
3160 case PACKET_ORIGDEV:
3161 {
3162 int val;
3163
3164 if (optlen < sizeof(val))
3165 return -EINVAL;
3166 if (copy_from_user(&val, optval, sizeof(val)))
3167 return -EFAULT;
3168
3169 po->origdev = !!val;
3170 return 0;
3171 }
3172 case PACKET_VNET_HDR:
3173 {
3174 int val;
3175
3176 if (sock->type != SOCK_RAW)
3177 return -EINVAL;
3178 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3179 return -EBUSY;
3180 if (optlen < sizeof(val))
3181 return -EINVAL;
3182 if (copy_from_user(&val, optval, sizeof(val)))
3183 return -EFAULT;
3184
3185 po->has_vnet_hdr = !!val;
3186 return 0;
3187 }
3188 case PACKET_TIMESTAMP:
3189 {
3190 int val;
3191
3192 if (optlen != sizeof(val))
3193 return -EINVAL;
3194 if (copy_from_user(&val, optval, sizeof(val)))
3195 return -EFAULT;
3196
3197 po->tp_tstamp = val;
3198 return 0;
3199 }
3200 case PACKET_FANOUT:
3201 {
3202 int val;
3203
3204 if (optlen != sizeof(val))
3205 return -EINVAL;
3206 if (copy_from_user(&val, optval, sizeof(val)))
3207 return -EFAULT;
3208
3209 return fanout_add(sk, val & 0xffff, val >> 16);
3210 }
3211 default:
3212 return -ENOPROTOOPT;
3213 }
3214 }
3215
3216 static int packet_getsockopt(struct socket *sock, int level, int optname,
3217 char __user *optval, int __user *optlen)
3218 {
3219 int len;
3220 int val, lv = sizeof(val);
3221 struct sock *sk = sock->sk;
3222 struct packet_sock *po = pkt_sk(sk);
3223 void *data = &val;
3224 struct tpacket_stats st;
3225 union tpacket_stats_u st_u;
3226
3227 if (level != SOL_PACKET)
3228 return -ENOPROTOOPT;
3229
3230 if (get_user(len, optlen))
3231 return -EFAULT;
3232
3233 if (len < 0)
3234 return -EINVAL;
3235
3236 switch (optname) {
3237 case PACKET_STATISTICS:
3238 spin_lock_bh(&sk->sk_receive_queue.lock);
3239 if (po->tp_version == TPACKET_V3) {
3240 lv = sizeof(struct tpacket_stats_v3);
3241 memcpy(&st_u.stats3, &po->stats,
3242 sizeof(struct tpacket_stats));
3243 st_u.stats3.tp_freeze_q_cnt =
3244 po->stats_u.stats3.tp_freeze_q_cnt;
3245 st_u.stats3.tp_packets += po->stats.tp_drops;
3246 data = &st_u.stats3;
3247 } else {
3248 lv = sizeof(struct tpacket_stats);
3249 st = po->stats;
3250 st.tp_packets += st.tp_drops;
3251 data = &st;
3252 }
3253 memset(&po->stats, 0, sizeof(st));
3254 spin_unlock_bh(&sk->sk_receive_queue.lock);
3255 break;
3256 case PACKET_AUXDATA:
3257 val = po->auxdata;
3258 break;
3259 case PACKET_ORIGDEV:
3260 val = po->origdev;
3261 break;
3262 case PACKET_VNET_HDR:
3263 val = po->has_vnet_hdr;
3264 break;
3265 case PACKET_VERSION:
3266 val = po->tp_version;
3267 break;
3268 case PACKET_HDRLEN:
3269 if (len > sizeof(int))
3270 len = sizeof(int);
3271 if (copy_from_user(&val, optval, len))
3272 return -EFAULT;
3273 switch (val) {
3274 case TPACKET_V1:
3275 val = sizeof(struct tpacket_hdr);
3276 break;
3277 case TPACKET_V2:
3278 val = sizeof(struct tpacket2_hdr);
3279 break;
3280 case TPACKET_V3:
3281 val = sizeof(struct tpacket3_hdr);
3282 break;
3283 default:
3284 return -EINVAL;
3285 }
3286 break;
3287 case PACKET_RESERVE:
3288 val = po->tp_reserve;
3289 break;
3290 case PACKET_LOSS:
3291 val = po->tp_loss;
3292 break;
3293 case PACKET_TIMESTAMP:
3294 val = po->tp_tstamp;
3295 break;
3296 case PACKET_FANOUT:
3297 val = (po->fanout ?
3298 ((u32)po->fanout->id |
3299 ((u32)po->fanout->type << 16)) :
3300 0);
3301 break;
3302 default:
3303 return -ENOPROTOOPT;
3304 }
3305
3306 if (len > lv)
3307 len = lv;
3308 if (put_user(len, optlen))
3309 return -EFAULT;
3310 if (copy_to_user(optval, data, len))
3311 return -EFAULT;
3312 return 0;
3313 }
3314
3315
3316 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3317 {
3318 struct sock *sk;
3319 struct hlist_node *node;
3320 struct net_device *dev = data;
3321 struct net *net = dev_net(dev);
3322
3323 rcu_read_lock();
3324 sk_for_each_rcu(sk, node, &net->packet.sklist) {
3325 struct packet_sock *po = pkt_sk(sk);
3326
3327 switch (msg) {
3328 case NETDEV_UNREGISTER:
3329 if (po->mclist)
3330 packet_dev_mclist(dev, po->mclist, -1);
3331 /* fallthrough */
3332
3333 case NETDEV_DOWN:
3334 if (dev->ifindex == po->ifindex) {
3335 spin_lock(&po->bind_lock);
3336 if (po->running) {
3337 __unregister_prot_hook(sk, false);
3338 sk->sk_err = ENETDOWN;
3339 if (!sock_flag(sk, SOCK_DEAD))
3340 sk->sk_error_report(sk);
3341 }
3342 if (msg == NETDEV_UNREGISTER) {
3343 po->ifindex = -1;
3344 if (po->prot_hook.dev)
3345 dev_put(po->prot_hook.dev);
3346 po->prot_hook.dev = NULL;
3347 }
3348 spin_unlock(&po->bind_lock);
3349 }
3350 break;
3351 case NETDEV_UP:
3352 if (dev->ifindex == po->ifindex) {
3353 spin_lock(&po->bind_lock);
3354 if (po->num)
3355 register_prot_hook(sk);
3356 spin_unlock(&po->bind_lock);
3357 }
3358 break;
3359 }
3360 }
3361 rcu_read_unlock();
3362 return NOTIFY_DONE;
3363 }
3364
3365
3366 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3367 unsigned long arg)
3368 {
3369 struct sock *sk = sock->sk;
3370
3371 switch (cmd) {
3372 case SIOCOUTQ:
3373 {
3374 int amount = sk_wmem_alloc_get(sk);
3375
3376 return put_user(amount, (int __user *)arg);
3377 }
3378 case SIOCINQ:
3379 {
3380 struct sk_buff *skb;
3381 int amount = 0;
3382
3383 spin_lock_bh(&sk->sk_receive_queue.lock);
3384 skb = skb_peek(&sk->sk_receive_queue);
3385 if (skb)
3386 amount = skb->len;
3387 spin_unlock_bh(&sk->sk_receive_queue.lock);
3388 return put_user(amount, (int __user *)arg);
3389 }
3390 case SIOCGSTAMP:
3391 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3392 case SIOCGSTAMPNS:
3393 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3394
3395 #ifdef CONFIG_INET
3396 case SIOCADDRT:
3397 case SIOCDELRT:
3398 case SIOCDARP:
3399 case SIOCGARP:
3400 case SIOCSARP:
3401 case SIOCGIFADDR:
3402 case SIOCSIFADDR:
3403 case SIOCGIFBRDADDR:
3404 case SIOCSIFBRDADDR:
3405 case SIOCGIFNETMASK:
3406 case SIOCSIFNETMASK:
3407 case SIOCGIFDSTADDR:
3408 case SIOCSIFDSTADDR:
3409 case SIOCSIFFLAGS:
3410 return inet_dgram_ops.ioctl(sock, cmd, arg);
3411 #endif
3412
3413 default:
3414 return -ENOIOCTLCMD;
3415 }
3416 return 0;
3417 }
3418
3419 static unsigned int packet_poll(struct file *file, struct socket *sock,
3420 poll_table *wait)
3421 {
3422 struct sock *sk = sock->sk;
3423 struct packet_sock *po = pkt_sk(sk);
3424 unsigned int mask = datagram_poll(file, sock, wait);
3425
3426 spin_lock_bh(&sk->sk_receive_queue.lock);
3427 if (po->rx_ring.pg_vec) {
3428 if (!packet_previous_rx_frame(po, &po->rx_ring,
3429 TP_STATUS_KERNEL))
3430 mask |= POLLIN | POLLRDNORM;
3431 }
3432 spin_unlock_bh(&sk->sk_receive_queue.lock);
3433 spin_lock_bh(&sk->sk_write_queue.lock);
3434 if (po->tx_ring.pg_vec) {
3435 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3436 mask |= POLLOUT | POLLWRNORM;
3437 }
3438 spin_unlock_bh(&sk->sk_write_queue.lock);
3439 return mask;
3440 }
3441
3442
3443 /* Dirty? Well, I still did not learn better way to account
3444 * for user mmaps.
3445 */
3446
3447 static void packet_mm_open(struct vm_area_struct *vma)
3448 {
3449 struct file *file = vma->vm_file;
3450 struct socket *sock = file->private_data;
3451 struct sock *sk = sock->sk;
3452
3453 if (sk)
3454 atomic_inc(&pkt_sk(sk)->mapped);
3455 }
3456
3457 static void packet_mm_close(struct vm_area_struct *vma)
3458 {
3459 struct file *file = vma->vm_file;
3460 struct socket *sock = file->private_data;
3461 struct sock *sk = sock->sk;
3462
3463 if (sk)
3464 atomic_dec(&pkt_sk(sk)->mapped);
3465 }
3466
3467 static const struct vm_operations_struct packet_mmap_ops = {
3468 .open = packet_mm_open,
3469 .close = packet_mm_close,
3470 };
3471
3472 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3473 unsigned int len)
3474 {
3475 int i;
3476
3477 for (i = 0; i < len; i++) {
3478 if (likely(pg_vec[i].buffer)) {
3479 if (is_vmalloc_addr(pg_vec[i].buffer))
3480 vfree(pg_vec[i].buffer);
3481 else
3482 free_pages((unsigned long)pg_vec[i].buffer,
3483 order);
3484 pg_vec[i].buffer = NULL;
3485 }
3486 }
3487 kfree(pg_vec);
3488 }
3489
3490 static char *alloc_one_pg_vec_page(unsigned long order)
3491 {
3492 char *buffer = NULL;
3493 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3494 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3495
3496 buffer = (char *) __get_free_pages(gfp_flags, order);
3497
3498 if (buffer)
3499 return buffer;
3500
3501 /*
3502 * __get_free_pages failed, fall back to vmalloc
3503 */
3504 buffer = vzalloc((1 << order) * PAGE_SIZE);
3505
3506 if (buffer)
3507 return buffer;
3508
3509 /*
3510 * vmalloc failed, lets dig into swap here
3511 */
3512 gfp_flags &= ~__GFP_NORETRY;
3513 buffer = (char *)__get_free_pages(gfp_flags, order);
3514 if (buffer)
3515 return buffer;
3516
3517 /*
3518 * complete and utter failure
3519 */
3520 return NULL;
3521 }
3522
3523 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3524 {
3525 unsigned int block_nr = req->tp_block_nr;
3526 struct pgv *pg_vec;
3527 int i;
3528
3529 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3530 if (unlikely(!pg_vec))
3531 goto out;
3532
3533 for (i = 0; i < block_nr; i++) {
3534 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3535 if (unlikely(!pg_vec[i].buffer))
3536 goto out_free_pgvec;
3537 }
3538
3539 out:
3540 return pg_vec;
3541
3542 out_free_pgvec:
3543 free_pg_vec(pg_vec, order, block_nr);
3544 pg_vec = NULL;
3545 goto out;
3546 }
3547
3548 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3549 int closing, int tx_ring)
3550 {
3551 struct pgv *pg_vec = NULL;
3552 struct packet_sock *po = pkt_sk(sk);
3553 int was_running, order = 0;
3554 struct packet_ring_buffer *rb;
3555 struct sk_buff_head *rb_queue;
3556 __be16 num;
3557 int err = -EINVAL;
3558 /* Added to avoid minimal code churn */
3559 struct tpacket_req *req = &req_u->req;
3560
3561 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3562 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3563 WARN(1, "Tx-ring is not supported.\n");
3564 goto out;
3565 }
3566
3567 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3568 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3569
3570 err = -EBUSY;
3571 if (!closing) {
3572 if (atomic_read(&po->mapped))
3573 goto out;
3574 if (atomic_read(&rb->pending))
3575 goto out;
3576 }
3577
3578 if (req->tp_block_nr) {
3579 /* Sanity tests and some calculations */
3580 err = -EBUSY;
3581 if (unlikely(rb->pg_vec))
3582 goto out;
3583
3584 switch (po->tp_version) {
3585 case TPACKET_V1:
3586 po->tp_hdrlen = TPACKET_HDRLEN;
3587 break;
3588 case TPACKET_V2:
3589 po->tp_hdrlen = TPACKET2_HDRLEN;
3590 break;
3591 case TPACKET_V3:
3592 po->tp_hdrlen = TPACKET3_HDRLEN;
3593 break;
3594 }
3595
3596 err = -EINVAL;
3597 if (unlikely((int)req->tp_block_size <= 0))
3598 goto out;
3599 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3600 goto out;
3601 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3602 po->tp_reserve))
3603 goto out;
3604 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3605 goto out;
3606
3607 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3608 if (unlikely(rb->frames_per_block <= 0))
3609 goto out;
3610 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3611 req->tp_frame_nr))
3612 goto out;
3613
3614 err = -ENOMEM;
3615 order = get_order(req->tp_block_size);
3616 pg_vec = alloc_pg_vec(req, order);
3617 if (unlikely(!pg_vec))
3618 goto out;
3619 switch (po->tp_version) {
3620 case TPACKET_V3:
3621 /* Transmit path is not supported. We checked
3622 * it above but just being paranoid
3623 */
3624 if (!tx_ring)
3625 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3626 break;
3627 default:
3628 break;
3629 }
3630 }
3631 /* Done */
3632 else {
3633 err = -EINVAL;
3634 if (unlikely(req->tp_frame_nr))
3635 goto out;
3636 }
3637
3638 lock_sock(sk);
3639
3640 /* Detach socket from network */
3641 spin_lock(&po->bind_lock);
3642 was_running = po->running;
3643 num = po->num;
3644 if (was_running) {
3645 po->num = 0;
3646 __unregister_prot_hook(sk, false);
3647 }
3648 spin_unlock(&po->bind_lock);
3649
3650 synchronize_net();
3651
3652 err = -EBUSY;
3653 mutex_lock(&po->pg_vec_lock);
3654 if (closing || atomic_read(&po->mapped) == 0) {
3655 err = 0;
3656 spin_lock_bh(&rb_queue->lock);
3657 swap(rb->pg_vec, pg_vec);
3658 rb->frame_max = (req->tp_frame_nr - 1);
3659 rb->head = 0;
3660 rb->frame_size = req->tp_frame_size;
3661 spin_unlock_bh(&rb_queue->lock);
3662
3663 swap(rb->pg_vec_order, order);
3664 swap(rb->pg_vec_len, req->tp_block_nr);
3665
3666 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3667 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3668 tpacket_rcv : packet_rcv;
3669 skb_queue_purge(rb_queue);
3670 if (atomic_read(&po->mapped))
3671 pr_err("packet_mmap: vma is busy: %d\n",
3672 atomic_read(&po->mapped));
3673 }
3674 mutex_unlock(&po->pg_vec_lock);
3675
3676 spin_lock(&po->bind_lock);
3677 if (was_running) {
3678 po->num = num;
3679 register_prot_hook(sk);
3680 }
3681 spin_unlock(&po->bind_lock);
3682 if (closing && (po->tp_version > TPACKET_V2)) {
3683 /* Because we don't support block-based V3 on tx-ring */
3684 if (!tx_ring)
3685 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3686 }
3687 release_sock(sk);
3688
3689 if (pg_vec)
3690 free_pg_vec(pg_vec, order, req->tp_block_nr);
3691 out:
3692 return err;
3693 }
3694
3695 static int packet_mmap(struct file *file, struct socket *sock,
3696 struct vm_area_struct *vma)
3697 {
3698 struct sock *sk = sock->sk;
3699 struct packet_sock *po = pkt_sk(sk);
3700 unsigned long size, expected_size;
3701 struct packet_ring_buffer *rb;
3702 unsigned long start;
3703 int err = -EINVAL;
3704 int i;
3705
3706 if (vma->vm_pgoff)
3707 return -EINVAL;
3708
3709 mutex_lock(&po->pg_vec_lock);
3710
3711 expected_size = 0;
3712 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3713 if (rb->pg_vec) {
3714 expected_size += rb->pg_vec_len
3715 * rb->pg_vec_pages
3716 * PAGE_SIZE;
3717 }
3718 }
3719
3720 if (expected_size == 0)
3721 goto out;
3722
3723 size = vma->vm_end - vma->vm_start;
3724 if (size != expected_size)
3725 goto out;
3726
3727 start = vma->vm_start;
3728 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3729 if (rb->pg_vec == NULL)
3730 continue;
3731
3732 for (i = 0; i < rb->pg_vec_len; i++) {
3733 struct page *page;
3734 void *kaddr = rb->pg_vec[i].buffer;
3735 int pg_num;
3736
3737 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3738 page = pgv_to_page(kaddr);
3739 err = vm_insert_page(vma, start, page);
3740 if (unlikely(err))
3741 goto out;
3742 start += PAGE_SIZE;
3743 kaddr += PAGE_SIZE;
3744 }
3745 }
3746 }
3747
3748 atomic_inc(&po->mapped);
3749 vma->vm_ops = &packet_mmap_ops;
3750 err = 0;
3751
3752 out:
3753 mutex_unlock(&po->pg_vec_lock);
3754 return err;
3755 }
3756
3757 static const struct proto_ops packet_ops_spkt = {
3758 .family = PF_PACKET,
3759 .owner = THIS_MODULE,
3760 .release = packet_release,
3761 .bind = packet_bind_spkt,
3762 .connect = sock_no_connect,
3763 .socketpair = sock_no_socketpair,
3764 .accept = sock_no_accept,
3765 .getname = packet_getname_spkt,
3766 .poll = datagram_poll,
3767 .ioctl = packet_ioctl,
3768 .listen = sock_no_listen,
3769 .shutdown = sock_no_shutdown,
3770 .setsockopt = sock_no_setsockopt,
3771 .getsockopt = sock_no_getsockopt,
3772 .sendmsg = packet_sendmsg_spkt,
3773 .recvmsg = packet_recvmsg,
3774 .mmap = sock_no_mmap,
3775 .sendpage = sock_no_sendpage,
3776 };
3777
3778 static const struct proto_ops packet_ops = {
3779 .family = PF_PACKET,
3780 .owner = THIS_MODULE,
3781 .release = packet_release,
3782 .bind = packet_bind,
3783 .connect = sock_no_connect,
3784 .socketpair = sock_no_socketpair,
3785 .accept = sock_no_accept,
3786 .getname = packet_getname,
3787 .poll = packet_poll,
3788 .ioctl = packet_ioctl,
3789 .listen = sock_no_listen,
3790 .shutdown = sock_no_shutdown,
3791 .setsockopt = packet_setsockopt,
3792 .getsockopt = packet_getsockopt,
3793 .sendmsg = packet_sendmsg,
3794 .recvmsg = packet_recvmsg,
3795 .mmap = packet_mmap,
3796 .sendpage = sock_no_sendpage,
3797 };
3798
3799 static const struct net_proto_family packet_family_ops = {
3800 .family = PF_PACKET,
3801 .create = packet_create,
3802 .owner = THIS_MODULE,
3803 };
3804
3805 static struct notifier_block packet_netdev_notifier = {
3806 .notifier_call = packet_notifier,
3807 };
3808
3809 #ifdef CONFIG_PROC_FS
3810
3811 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3812 __acquires(RCU)
3813 {
3814 struct net *net = seq_file_net(seq);
3815
3816 rcu_read_lock();
3817 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3818 }
3819
3820 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3821 {
3822 struct net *net = seq_file_net(seq);
3823 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3824 }
3825
3826 static void packet_seq_stop(struct seq_file *seq, void *v)
3827 __releases(RCU)
3828 {
3829 rcu_read_unlock();
3830 }
3831
3832 static int packet_seq_show(struct seq_file *seq, void *v)
3833 {
3834 if (v == SEQ_START_TOKEN)
3835 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3836 else {
3837 struct sock *s = sk_entry(v);
3838 const struct packet_sock *po = pkt_sk(s);
3839
3840 seq_printf(seq,
3841 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3842 s,
3843 atomic_read(&s->sk_refcnt),
3844 s->sk_type,
3845 ntohs(po->num),
3846 po->ifindex,
3847 po->running,
3848 atomic_read(&s->sk_rmem_alloc),
3849 sock_i_uid(s),
3850 sock_i_ino(s));
3851 }
3852
3853 return 0;
3854 }
3855
3856 static const struct seq_operations packet_seq_ops = {
3857 .start = packet_seq_start,
3858 .next = packet_seq_next,
3859 .stop = packet_seq_stop,
3860 .show = packet_seq_show,
3861 };
3862
3863 static int packet_seq_open(struct inode *inode, struct file *file)
3864 {
3865 return seq_open_net(inode, file, &packet_seq_ops,
3866 sizeof(struct seq_net_private));
3867 }
3868
3869 static const struct file_operations packet_seq_fops = {
3870 .owner = THIS_MODULE,
3871 .open = packet_seq_open,
3872 .read = seq_read,
3873 .llseek = seq_lseek,
3874 .release = seq_release_net,
3875 };
3876
3877 #endif
3878
3879 static int __net_init packet_net_init(struct net *net)
3880 {
3881 spin_lock_init(&net->packet.sklist_lock);
3882 INIT_HLIST_HEAD(&net->packet.sklist);
3883
3884 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3885 return -ENOMEM;
3886
3887 return 0;
3888 }
3889
3890 static void __net_exit packet_net_exit(struct net *net)
3891 {
3892 proc_net_remove(net, "packet");
3893 }
3894
3895 static struct pernet_operations packet_net_ops = {
3896 .init = packet_net_init,
3897 .exit = packet_net_exit,
3898 };
3899
3900
3901 static void __exit packet_exit(void)
3902 {
3903 unregister_netdevice_notifier(&packet_netdev_notifier);
3904 unregister_pernet_subsys(&packet_net_ops);
3905 sock_unregister(PF_PACKET);
3906 proto_unregister(&packet_proto);
3907 }
3908
3909 static int __init packet_init(void)
3910 {
3911 int rc = proto_register(&packet_proto, 0);
3912
3913 if (rc != 0)
3914 goto out;
3915
3916 sock_register(&packet_family_ops);
3917 register_pernet_subsys(&packet_net_ops);
3918 register_netdevice_notifier(&packet_netdev_notifier);
3919 out:
3920 return rc;
3921 }
3922
3923 module_init(packet_init);
3924 module_exit(packet_exit);
3925 MODULE_LICENSE("GPL");
3926 MODULE_ALIAS_NETPROTO(PF_PACKET);
Linus' kernel tree