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net: cleanup unsigned to unsigned int
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / packet / af_packet.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * PACKET - implements raw packet sockets.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 *
12 * Fixes:
13 * Alan Cox : verify_area() now used correctly
14 * Alan Cox : new skbuff lists, look ma no backlogs!
15 * Alan Cox : tidied skbuff lists.
16 * Alan Cox : Now uses generic datagram routines I
17 * added. Also fixed the peek/read crash
18 * from all old Linux datagram code.
19 * Alan Cox : Uses the improved datagram code.
20 * Alan Cox : Added NULL's for socket options.
21 * Alan Cox : Re-commented the code.
22 * Alan Cox : Use new kernel side addressing
23 * Rob Janssen : Correct MTU usage.
24 * Dave Platt : Counter leaks caused by incorrect
25 * interrupt locking and some slightly
26 * dubious gcc output. Can you read
27 * compiler: it said _VOLATILE_
28 * Richard Kooijman : Timestamp fixes.
29 * Alan Cox : New buffers. Use sk->mac.raw.
30 * Alan Cox : sendmsg/recvmsg support.
31 * Alan Cox : Protocol setting support
32 * Alexey Kuznetsov : Untied from IPv4 stack.
33 * Cyrus Durgin : Fixed kerneld for kmod.
34 * Michal Ostrowski : Module initialization cleanup.
35 * Ulises Alonso : Frame number limit removal and
36 * packet_set_ring memory leak.
37 * Eric Biederman : Allow for > 8 byte hardware addresses.
38 * The convention is that longer addresses
39 * will simply extend the hardware address
40 * byte arrays at the end of sockaddr_ll
41 * and packet_mreq.
42 * Johann Baudy : Added TX RING.
43 * Chetan Loke : Implemented TPACKET_V3 block abstraction
44 * layer.
45 * Copyright (C) 2011, <lokec@ccs.neu.edu>
46 *
47 *
48 * This program is free software; you can redistribute it and/or
49 * modify it under the terms of the GNU General Public License
50 * as published by the Free Software Foundation; either version
51 * 2 of the License, or (at your option) any later version.
52 *
53 */
54
55 #include <linux/types.h>
56 #include <linux/mm.h>
57 #include <linux/capability.h>
58 #include <linux/fcntl.h>
59 #include <linux/socket.h>
60 #include <linux/in.h>
61 #include <linux/inet.h>
62 #include <linux/netdevice.h>
63 #include <linux/if_packet.h>
64 #include <linux/wireless.h>
65 #include <linux/kernel.h>
66 #include <linux/kmod.h>
67 #include <linux/slab.h>
68 #include <linux/vmalloc.h>
69 #include <net/net_namespace.h>
70 #include <net/ip.h>
71 #include <net/protocol.h>
72 #include <linux/skbuff.h>
73 #include <net/sock.h>
74 #include <linux/errno.h>
75 #include <linux/timer.h>
76 #include <asm/uaccess.h>
77 #include <asm/ioctls.h>
78 #include <asm/page.h>
79 #include <asm/cacheflush.h>
80 #include <asm/io.h>
81 #include <linux/proc_fs.h>
82 #include <linux/seq_file.h>
83 #include <linux/poll.h>
84 #include <linux/module.h>
85 #include <linux/init.h>
86 #include <linux/mutex.h>
87 #include <linux/if_vlan.h>
88 #include <linux/virtio_net.h>
89 #include <linux/errqueue.h>
90 #include <linux/net_tstamp.h>
91
92 #ifdef CONFIG_INET
93 #include <net/inet_common.h>
94 #endif
95
96 /*
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
535 rtnl_lock();
536 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
537 if (unlikely(!dev)) {
538 rtnl_unlock();
539 return DEFAULT_PRB_RETIRE_TOV;
540 }
541 err = __ethtool_get_settings(dev, &ecmd);
542 rtnl_unlock();
543 if (!err) {
544 switch (ecmd.speed) {
545 case SPEED_10000:
546 msec = 1;
547 div = 10000/1000;
548 break;
549 case SPEED_1000:
550 msec = 1;
551 div = 1000/1000;
552 break;
553 /*
554 * If the link speed is so slow you don't really
555 * need to worry about perf anyways
556 */
557 case SPEED_100:
558 case SPEED_10:
559 default:
560 return DEFAULT_PRB_RETIRE_TOV;
561 }
562 }
563
564 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
565
566 if (div)
567 mbits /= div;
568
569 tmo = mbits * msec;
570
571 if (div)
572 return tmo+1;
573 return tmo;
574 }
575
576 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
577 union tpacket_req_u *req_u)
578 {
579 p1->feature_req_word = req_u->req3.tp_feature_req_word;
580 }
581
582 static void init_prb_bdqc(struct packet_sock *po,
583 struct packet_ring_buffer *rb,
584 struct pgv *pg_vec,
585 union tpacket_req_u *req_u, int tx_ring)
586 {
587 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
588 struct tpacket_block_desc *pbd;
589
590 memset(p1, 0x0, sizeof(*p1));
591
592 p1->knxt_seq_num = 1;
593 p1->pkbdq = pg_vec;
594 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
595 p1->pkblk_start = (char *)pg_vec[0].buffer;
596 p1->kblk_size = req_u->req3.tp_block_size;
597 p1->knum_blocks = req_u->req3.tp_block_nr;
598 p1->hdrlen = po->tp_hdrlen;
599 p1->version = po->tp_version;
600 p1->last_kactive_blk_num = 0;
601 po->stats_u.stats3.tp_freeze_q_cnt = 0;
602 if (req_u->req3.tp_retire_blk_tov)
603 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
604 else
605 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
606 req_u->req3.tp_block_size);
607 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
608 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
609
610 prb_init_ft_ops(p1, req_u);
611 prb_setup_retire_blk_timer(po, tx_ring);
612 prb_open_block(p1, pbd);
613 }
614
615 /* Do NOT update the last_blk_num first.
616 * Assumes sk_buff_head lock is held.
617 */
618 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
619 {
620 mod_timer(&pkc->retire_blk_timer,
621 jiffies + pkc->tov_in_jiffies);
622 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
623 }
624
625 /*
626 * Timer logic:
627 * 1) We refresh the timer only when we open a block.
628 * By doing this we don't waste cycles refreshing the timer
629 * on packet-by-packet basis.
630 *
631 * With a 1MB block-size, on a 1Gbps line, it will take
632 * i) ~8 ms to fill a block + ii) memcpy etc.
633 * In this cut we are not accounting for the memcpy time.
634 *
635 * So, if the user sets the 'tmo' to 10ms then the timer
636 * will never fire while the block is still getting filled
637 * (which is what we want). However, the user could choose
638 * to close a block early and that's fine.
639 *
640 * But when the timer does fire, we check whether or not to refresh it.
641 * Since the tmo granularity is in msecs, it is not too expensive
642 * to refresh the timer, lets say every '8' msecs.
643 * Either the user can set the 'tmo' or we can derive it based on
644 * a) line-speed and b) block-size.
645 * prb_calc_retire_blk_tmo() calculates the tmo.
646 *
647 */
648 static void prb_retire_rx_blk_timer_expired(unsigned long data)
649 {
650 struct packet_sock *po = (struct packet_sock *)data;
651 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
652 unsigned int frozen;
653 struct tpacket_block_desc *pbd;
654
655 spin_lock(&po->sk.sk_receive_queue.lock);
656
657 frozen = prb_queue_frozen(pkc);
658 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
659
660 if (unlikely(pkc->delete_blk_timer))
661 goto out;
662
663 /* We only need to plug the race when the block is partially filled.
664 * tpacket_rcv:
665 * lock(); increment BLOCK_NUM_PKTS; unlock()
666 * copy_bits() is in progress ...
667 * timer fires on other cpu:
668 * we can't retire the current block because copy_bits
669 * is in progress.
670 *
671 */
672 if (BLOCK_NUM_PKTS(pbd)) {
673 while (atomic_read(&pkc->blk_fill_in_prog)) {
674 /* Waiting for skb_copy_bits to finish... */
675 cpu_relax();
676 }
677 }
678
679 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
680 if (!frozen) {
681 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
682 if (!prb_dispatch_next_block(pkc, po))
683 goto refresh_timer;
684 else
685 goto out;
686 } else {
687 /* Case 1. Queue was frozen because user-space was
688 * lagging behind.
689 */
690 if (prb_curr_blk_in_use(pkc, pbd)) {
691 /*
692 * Ok, user-space is still behind.
693 * So just refresh the timer.
694 */
695 goto refresh_timer;
696 } else {
697 /* Case 2. queue was frozen,user-space caught up,
698 * now the link went idle && the timer fired.
699 * We don't have a block to close.So we open this
700 * block and restart the timer.
701 * opening a block thaws the queue,restarts timer
702 * Thawing/timer-refresh is a side effect.
703 */
704 prb_open_block(pkc, pbd);
705 goto out;
706 }
707 }
708 }
709
710 refresh_timer:
711 _prb_refresh_rx_retire_blk_timer(pkc);
712
713 out:
714 spin_unlock(&po->sk.sk_receive_queue.lock);
715 }
716
717 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
718 struct tpacket_block_desc *pbd1, __u32 status)
719 {
720 /* Flush everything minus the block header */
721
722 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
723 u8 *start, *end;
724
725 start = (u8 *)pbd1;
726
727 /* Skip the block header(we know header WILL fit in 4K) */
728 start += PAGE_SIZE;
729
730 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
731 for (; start < end; start += PAGE_SIZE)
732 flush_dcache_page(pgv_to_page(start));
733
734 smp_wmb();
735 #endif
736
737 /* Now update the block status. */
738
739 BLOCK_STATUS(pbd1) = status;
740
741 /* Flush the block header */
742
743 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
744 start = (u8 *)pbd1;
745 flush_dcache_page(pgv_to_page(start));
746
747 smp_wmb();
748 #endif
749 }
750
751 /*
752 * Side effect:
753 *
754 * 1) flush the block
755 * 2) Increment active_blk_num
756 *
757 * Note:We DONT refresh the timer on purpose.
758 * Because almost always the next block will be opened.
759 */
760 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
761 struct tpacket_block_desc *pbd1,
762 struct packet_sock *po, unsigned int stat)
763 {
764 __u32 status = TP_STATUS_USER | stat;
765
766 struct tpacket3_hdr *last_pkt;
767 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
768
769 if (po->stats.tp_drops)
770 status |= TP_STATUS_LOSING;
771
772 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
773 last_pkt->tp_next_offset = 0;
774
775 /* Get the ts of the last pkt */
776 if (BLOCK_NUM_PKTS(pbd1)) {
777 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
778 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
779 } else {
780 /* Ok, we tmo'd - so get the current time */
781 struct timespec ts;
782 getnstimeofday(&ts);
783 h1->ts_last_pkt.ts_sec = ts.tv_sec;
784 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
785 }
786
787 smp_wmb();
788
789 /* Flush the block */
790 prb_flush_block(pkc1, pbd1, status);
791
792 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
793 }
794
795 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
796 {
797 pkc->reset_pending_on_curr_blk = 0;
798 }
799
800 /*
801 * Side effect of opening a block:
802 *
803 * 1) prb_queue is thawed.
804 * 2) retire_blk_timer is refreshed.
805 *
806 */
807 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
808 struct tpacket_block_desc *pbd1)
809 {
810 struct timespec ts;
811 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
812
813 smp_rmb();
814
815 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd1))) {
816
817 /* We could have just memset this but we will lose the
818 * flexibility of making the priv area sticky
819 */
820 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
821 BLOCK_NUM_PKTS(pbd1) = 0;
822 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
823 getnstimeofday(&ts);
824 h1->ts_first_pkt.ts_sec = ts.tv_sec;
825 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
826 pkc1->pkblk_start = (char *)pbd1;
827 pkc1->nxt_offset = (char *)(pkc1->pkblk_start +
828 BLK_PLUS_PRIV(pkc1->blk_sizeof_priv));
829 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
830 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
831 pbd1->version = pkc1->version;
832 pkc1->prev = pkc1->nxt_offset;
833 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
834 prb_thaw_queue(pkc1);
835 _prb_refresh_rx_retire_blk_timer(pkc1);
836
837 smp_wmb();
838
839 return;
840 }
841
842 WARN(1, "ERROR block:%p is NOT FREE status:%d kactive_blk_num:%d\n",
843 pbd1, BLOCK_STATUS(pbd1), pkc1->kactive_blk_num);
844 dump_stack();
845 BUG();
846 }
847
848 /*
849 * Queue freeze logic:
850 * 1) Assume tp_block_nr = 8 blocks.
851 * 2) At time 't0', user opens Rx ring.
852 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
853 * 4) user-space is either sleeping or processing block '0'.
854 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
855 * it will close block-7,loop around and try to fill block '0'.
856 * call-flow:
857 * __packet_lookup_frame_in_block
858 * prb_retire_current_block()
859 * prb_dispatch_next_block()
860 * |->(BLOCK_STATUS == USER) evaluates to true
861 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
862 * 6) Now there are two cases:
863 * 6.1) Link goes idle right after the queue is frozen.
864 * But remember, the last open_block() refreshed the timer.
865 * When this timer expires,it will refresh itself so that we can
866 * re-open block-0 in near future.
867 * 6.2) Link is busy and keeps on receiving packets. This is a simple
868 * case and __packet_lookup_frame_in_block will check if block-0
869 * is free and can now be re-used.
870 */
871 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
872 struct packet_sock *po)
873 {
874 pkc->reset_pending_on_curr_blk = 1;
875 po->stats_u.stats3.tp_freeze_q_cnt++;
876 }
877
878 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
879
880 /*
881 * If the next block is free then we will dispatch it
882 * and return a good offset.
883 * Else, we will freeze the queue.
884 * So, caller must check the return value.
885 */
886 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
887 struct packet_sock *po)
888 {
889 struct tpacket_block_desc *pbd;
890
891 smp_rmb();
892
893 /* 1. Get current block num */
894 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
895
896 /* 2. If this block is currently in_use then freeze the queue */
897 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
898 prb_freeze_queue(pkc, po);
899 return NULL;
900 }
901
902 /*
903 * 3.
904 * open this block and return the offset where the first packet
905 * needs to get stored.
906 */
907 prb_open_block(pkc, pbd);
908 return (void *)pkc->nxt_offset;
909 }
910
911 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
912 struct packet_sock *po, unsigned int status)
913 {
914 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
915
916 /* retire/close the current block */
917 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
918 /*
919 * Plug the case where copy_bits() is in progress on
920 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
921 * have space to copy the pkt in the current block and
922 * called prb_retire_current_block()
923 *
924 * We don't need to worry about the TMO case because
925 * the timer-handler already handled this case.
926 */
927 if (!(status & TP_STATUS_BLK_TMO)) {
928 while (atomic_read(&pkc->blk_fill_in_prog)) {
929 /* Waiting for skb_copy_bits to finish... */
930 cpu_relax();
931 }
932 }
933 prb_close_block(pkc, pbd, po, status);
934 return;
935 }
936
937 WARN(1, "ERROR-pbd[%d]:%p\n", pkc->kactive_blk_num, pbd);
938 dump_stack();
939 BUG();
940 }
941
942 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
943 struct tpacket_block_desc *pbd)
944 {
945 return TP_STATUS_USER & BLOCK_STATUS(pbd);
946 }
947
948 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
949 {
950 return pkc->reset_pending_on_curr_blk;
951 }
952
953 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
954 {
955 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
956 atomic_dec(&pkc->blk_fill_in_prog);
957 }
958
959 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
960 struct tpacket3_hdr *ppd)
961 {
962 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
963 }
964
965 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
966 struct tpacket3_hdr *ppd)
967 {
968 ppd->hv1.tp_rxhash = 0;
969 }
970
971 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
972 struct tpacket3_hdr *ppd)
973 {
974 if (vlan_tx_tag_present(pkc->skb)) {
975 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
976 ppd->tp_status = TP_STATUS_VLAN_VALID;
977 } else {
978 ppd->hv1.tp_vlan_tci = ppd->tp_status = 0;
979 }
980 }
981
982 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
983 struct tpacket3_hdr *ppd)
984 {
985 prb_fill_vlan_info(pkc, ppd);
986
987 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
988 prb_fill_rxhash(pkc, ppd);
989 else
990 prb_clear_rxhash(pkc, ppd);
991 }
992
993 static void prb_fill_curr_block(char *curr,
994 struct tpacket_kbdq_core *pkc,
995 struct tpacket_block_desc *pbd,
996 unsigned int len)
997 {
998 struct tpacket3_hdr *ppd;
999
1000 ppd = (struct tpacket3_hdr *)curr;
1001 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1002 pkc->prev = curr;
1003 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1004 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1005 BLOCK_NUM_PKTS(pbd) += 1;
1006 atomic_inc(&pkc->blk_fill_in_prog);
1007 prb_run_all_ft_ops(pkc, ppd);
1008 }
1009
1010 /* Assumes caller has the sk->rx_queue.lock */
1011 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1012 struct sk_buff *skb,
1013 int status,
1014 unsigned int len
1015 )
1016 {
1017 struct tpacket_kbdq_core *pkc;
1018 struct tpacket_block_desc *pbd;
1019 char *curr, *end;
1020
1021 pkc = GET_PBDQC_FROM_RB(((struct packet_ring_buffer *)&po->rx_ring));
1022 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1023
1024 /* Queue is frozen when user space is lagging behind */
1025 if (prb_queue_frozen(pkc)) {
1026 /*
1027 * Check if that last block which caused the queue to freeze,
1028 * is still in_use by user-space.
1029 */
1030 if (prb_curr_blk_in_use(pkc, pbd)) {
1031 /* Can't record this packet */
1032 return NULL;
1033 } else {
1034 /*
1035 * Ok, the block was released by user-space.
1036 * Now let's open that block.
1037 * opening a block also thaws the queue.
1038 * Thawing is a side effect.
1039 */
1040 prb_open_block(pkc, pbd);
1041 }
1042 }
1043
1044 smp_mb();
1045 curr = pkc->nxt_offset;
1046 pkc->skb = skb;
1047 end = (char *) ((char *)pbd + pkc->kblk_size);
1048
1049 /* first try the current block */
1050 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1051 prb_fill_curr_block(curr, pkc, pbd, len);
1052 return (void *)curr;
1053 }
1054
1055 /* Ok, close the current block */
1056 prb_retire_current_block(pkc, po, 0);
1057
1058 /* Now, try to dispatch the next block */
1059 curr = (char *)prb_dispatch_next_block(pkc, po);
1060 if (curr) {
1061 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1062 prb_fill_curr_block(curr, pkc, pbd, len);
1063 return (void *)curr;
1064 }
1065
1066 /*
1067 * No free blocks are available.user_space hasn't caught up yet.
1068 * Queue was just frozen and now this packet will get dropped.
1069 */
1070 return NULL;
1071 }
1072
1073 static void *packet_current_rx_frame(struct packet_sock *po,
1074 struct sk_buff *skb,
1075 int status, unsigned int len)
1076 {
1077 char *curr = NULL;
1078 switch (po->tp_version) {
1079 case TPACKET_V1:
1080 case TPACKET_V2:
1081 curr = packet_lookup_frame(po, &po->rx_ring,
1082 po->rx_ring.head, status);
1083 return curr;
1084 case TPACKET_V3:
1085 return __packet_lookup_frame_in_block(po, skb, status, len);
1086 default:
1087 WARN(1, "TPACKET version not supported\n");
1088 BUG();
1089 return 0;
1090 }
1091 }
1092
1093 static void *prb_lookup_block(struct packet_sock *po,
1094 struct packet_ring_buffer *rb,
1095 unsigned int previous,
1096 int status)
1097 {
1098 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1099 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, previous);
1100
1101 if (status != BLOCK_STATUS(pbd))
1102 return NULL;
1103 return pbd;
1104 }
1105
1106 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1107 {
1108 unsigned int prev;
1109 if (rb->prb_bdqc.kactive_blk_num)
1110 prev = rb->prb_bdqc.kactive_blk_num-1;
1111 else
1112 prev = rb->prb_bdqc.knum_blocks-1;
1113 return prev;
1114 }
1115
1116 /* Assumes caller has held the rx_queue.lock */
1117 static void *__prb_previous_block(struct packet_sock *po,
1118 struct packet_ring_buffer *rb,
1119 int status)
1120 {
1121 unsigned int previous = prb_previous_blk_num(rb);
1122 return prb_lookup_block(po, rb, previous, status);
1123 }
1124
1125 static void *packet_previous_rx_frame(struct packet_sock *po,
1126 struct packet_ring_buffer *rb,
1127 int status)
1128 {
1129 if (po->tp_version <= TPACKET_V2)
1130 return packet_previous_frame(po, rb, status);
1131
1132 return __prb_previous_block(po, rb, status);
1133 }
1134
1135 static void packet_increment_rx_head(struct packet_sock *po,
1136 struct packet_ring_buffer *rb)
1137 {
1138 switch (po->tp_version) {
1139 case TPACKET_V1:
1140 case TPACKET_V2:
1141 return packet_increment_head(rb);
1142 case TPACKET_V3:
1143 default:
1144 WARN(1, "TPACKET version not supported.\n");
1145 BUG();
1146 return;
1147 }
1148 }
1149
1150 static void *packet_previous_frame(struct packet_sock *po,
1151 struct packet_ring_buffer *rb,
1152 int status)
1153 {
1154 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1155 return packet_lookup_frame(po, rb, previous, status);
1156 }
1157
1158 static void packet_increment_head(struct packet_ring_buffer *buff)
1159 {
1160 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1161 }
1162
1163 static void packet_sock_destruct(struct sock *sk)
1164 {
1165 skb_queue_purge(&sk->sk_error_queue);
1166
1167 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1168 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1169
1170 if (!sock_flag(sk, SOCK_DEAD)) {
1171 pr_err("Attempt to release alive packet socket: %p\n", sk);
1172 return;
1173 }
1174
1175 sk_refcnt_debug_dec(sk);
1176 }
1177
1178 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1179 {
1180 int x = atomic_read(&f->rr_cur) + 1;
1181
1182 if (x >= num)
1183 x = 0;
1184
1185 return x;
1186 }
1187
1188 static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1189 {
1190 u32 idx, hash = skb->rxhash;
1191
1192 idx = ((u64)hash * num) >> 32;
1193
1194 return f->arr[idx];
1195 }
1196
1197 static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1198 {
1199 int cur, old;
1200
1201 cur = atomic_read(&f->rr_cur);
1202 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1203 fanout_rr_next(f, num))) != cur)
1204 cur = old;
1205 return f->arr[cur];
1206 }
1207
1208 static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1209 {
1210 unsigned int cpu = smp_processor_id();
1211
1212 return f->arr[cpu % num];
1213 }
1214
1215 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1216 struct packet_type *pt, struct net_device *orig_dev)
1217 {
1218 struct packet_fanout *f = pt->af_packet_priv;
1219 unsigned int num = f->num_members;
1220 struct packet_sock *po;
1221 struct sock *sk;
1222
1223 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1224 !num) {
1225 kfree_skb(skb);
1226 return 0;
1227 }
1228
1229 switch (f->type) {
1230 case PACKET_FANOUT_HASH:
1231 default:
1232 if (f->defrag) {
1233 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1234 if (!skb)
1235 return 0;
1236 }
1237 skb_get_rxhash(skb);
1238 sk = fanout_demux_hash(f, skb, num);
1239 break;
1240 case PACKET_FANOUT_LB:
1241 sk = fanout_demux_lb(f, skb, num);
1242 break;
1243 case PACKET_FANOUT_CPU:
1244 sk = fanout_demux_cpu(f, skb, num);
1245 break;
1246 }
1247
1248 po = pkt_sk(sk);
1249
1250 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1251 }
1252
1253 static DEFINE_MUTEX(fanout_mutex);
1254 static LIST_HEAD(fanout_list);
1255
1256 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1257 {
1258 struct packet_fanout *f = po->fanout;
1259
1260 spin_lock(&f->lock);
1261 f->arr[f->num_members] = sk;
1262 smp_wmb();
1263 f->num_members++;
1264 spin_unlock(&f->lock);
1265 }
1266
1267 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1268 {
1269 struct packet_fanout *f = po->fanout;
1270 int i;
1271
1272 spin_lock(&f->lock);
1273 for (i = 0; i < f->num_members; i++) {
1274 if (f->arr[i] == sk)
1275 break;
1276 }
1277 BUG_ON(i >= f->num_members);
1278 f->arr[i] = f->arr[f->num_members - 1];
1279 f->num_members--;
1280 spin_unlock(&f->lock);
1281 }
1282
1283 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1284 {
1285 struct packet_sock *po = pkt_sk(sk);
1286 struct packet_fanout *f, *match;
1287 u8 type = type_flags & 0xff;
1288 u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
1289 int err;
1290
1291 switch (type) {
1292 case PACKET_FANOUT_HASH:
1293 case PACKET_FANOUT_LB:
1294 case PACKET_FANOUT_CPU:
1295 break;
1296 default:
1297 return -EINVAL;
1298 }
1299
1300 if (!po->running)
1301 return -EINVAL;
1302
1303 if (po->fanout)
1304 return -EALREADY;
1305
1306 mutex_lock(&fanout_mutex);
1307 match = NULL;
1308 list_for_each_entry(f, &fanout_list, list) {
1309 if (f->id == id &&
1310 read_pnet(&f->net) == sock_net(sk)) {
1311 match = f;
1312 break;
1313 }
1314 }
1315 err = -EINVAL;
1316 if (match && match->defrag != defrag)
1317 goto out;
1318 if (!match) {
1319 err = -ENOMEM;
1320 match = kzalloc(sizeof(*match), GFP_KERNEL);
1321 if (!match)
1322 goto out;
1323 write_pnet(&match->net, sock_net(sk));
1324 match->id = id;
1325 match->type = type;
1326 match->defrag = defrag;
1327 atomic_set(&match->rr_cur, 0);
1328 INIT_LIST_HEAD(&match->list);
1329 spin_lock_init(&match->lock);
1330 atomic_set(&match->sk_ref, 0);
1331 match->prot_hook.type = po->prot_hook.type;
1332 match->prot_hook.dev = po->prot_hook.dev;
1333 match->prot_hook.func = packet_rcv_fanout;
1334 match->prot_hook.af_packet_priv = match;
1335 dev_add_pack(&match->prot_hook);
1336 list_add(&match->list, &fanout_list);
1337 }
1338 err = -EINVAL;
1339 if (match->type == type &&
1340 match->prot_hook.type == po->prot_hook.type &&
1341 match->prot_hook.dev == po->prot_hook.dev) {
1342 err = -ENOSPC;
1343 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1344 __dev_remove_pack(&po->prot_hook);
1345 po->fanout = match;
1346 atomic_inc(&match->sk_ref);
1347 __fanout_link(sk, po);
1348 err = 0;
1349 }
1350 }
1351 out:
1352 mutex_unlock(&fanout_mutex);
1353 return err;
1354 }
1355
1356 static void fanout_release(struct sock *sk)
1357 {
1358 struct packet_sock *po = pkt_sk(sk);
1359 struct packet_fanout *f;
1360
1361 f = po->fanout;
1362 if (!f)
1363 return;
1364
1365 po->fanout = NULL;
1366
1367 mutex_lock(&fanout_mutex);
1368 if (atomic_dec_and_test(&f->sk_ref)) {
1369 list_del(&f->list);
1370 dev_remove_pack(&f->prot_hook);
1371 kfree(f);
1372 }
1373 mutex_unlock(&fanout_mutex);
1374 }
1375
1376 static const struct proto_ops packet_ops;
1377
1378 static const struct proto_ops packet_ops_spkt;
1379
1380 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1381 struct packet_type *pt, struct net_device *orig_dev)
1382 {
1383 struct sock *sk;
1384 struct sockaddr_pkt *spkt;
1385
1386 /*
1387 * When we registered the protocol we saved the socket in the data
1388 * field for just this event.
1389 */
1390
1391 sk = pt->af_packet_priv;
1392
1393 /*
1394 * Yank back the headers [hope the device set this
1395 * right or kerboom...]
1396 *
1397 * Incoming packets have ll header pulled,
1398 * push it back.
1399 *
1400 * For outgoing ones skb->data == skb_mac_header(skb)
1401 * so that this procedure is noop.
1402 */
1403
1404 if (skb->pkt_type == PACKET_LOOPBACK)
1405 goto out;
1406
1407 if (!net_eq(dev_net(dev), sock_net(sk)))
1408 goto out;
1409
1410 skb = skb_share_check(skb, GFP_ATOMIC);
1411 if (skb == NULL)
1412 goto oom;
1413
1414 /* drop any routing info */
1415 skb_dst_drop(skb);
1416
1417 /* drop conntrack reference */
1418 nf_reset(skb);
1419
1420 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1421
1422 skb_push(skb, skb->data - skb_mac_header(skb));
1423
1424 /*
1425 * The SOCK_PACKET socket receives _all_ frames.
1426 */
1427
1428 spkt->spkt_family = dev->type;
1429 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1430 spkt->spkt_protocol = skb->protocol;
1431
1432 /*
1433 * Charge the memory to the socket. This is done specifically
1434 * to prevent sockets using all the memory up.
1435 */
1436
1437 if (sock_queue_rcv_skb(sk, skb) == 0)
1438 return 0;
1439
1440 out:
1441 kfree_skb(skb);
1442 oom:
1443 return 0;
1444 }
1445
1446
1447 /*
1448 * Output a raw packet to a device layer. This bypasses all the other
1449 * protocol layers and you must therefore supply it with a complete frame
1450 */
1451
1452 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1453 struct msghdr *msg, size_t len)
1454 {
1455 struct sock *sk = sock->sk;
1456 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1457 struct sk_buff *skb = NULL;
1458 struct net_device *dev;
1459 __be16 proto = 0;
1460 int err;
1461 int extra_len = 0;
1462
1463 /*
1464 * Get and verify the address.
1465 */
1466
1467 if (saddr) {
1468 if (msg->msg_namelen < sizeof(struct sockaddr))
1469 return -EINVAL;
1470 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1471 proto = saddr->spkt_protocol;
1472 } else
1473 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1474
1475 /*
1476 * Find the device first to size check it
1477 */
1478
1479 saddr->spkt_device[13] = 0;
1480 retry:
1481 rcu_read_lock();
1482 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1483 err = -ENODEV;
1484 if (dev == NULL)
1485 goto out_unlock;
1486
1487 err = -ENETDOWN;
1488 if (!(dev->flags & IFF_UP))
1489 goto out_unlock;
1490
1491 /*
1492 * You may not queue a frame bigger than the mtu. This is the lowest level
1493 * raw protocol and you must do your own fragmentation at this level.
1494 */
1495
1496 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1497 if (!netif_supports_nofcs(dev)) {
1498 err = -EPROTONOSUPPORT;
1499 goto out_unlock;
1500 }
1501 extra_len = 4; /* We're doing our own CRC */
1502 }
1503
1504 err = -EMSGSIZE;
1505 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1506 goto out_unlock;
1507
1508 if (!skb) {
1509 size_t reserved = LL_RESERVED_SPACE(dev);
1510 int tlen = dev->needed_tailroom;
1511 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1512
1513 rcu_read_unlock();
1514 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1515 if (skb == NULL)
1516 return -ENOBUFS;
1517 /* FIXME: Save some space for broken drivers that write a hard
1518 * header at transmission time by themselves. PPP is the notable
1519 * one here. This should really be fixed at the driver level.
1520 */
1521 skb_reserve(skb, reserved);
1522 skb_reset_network_header(skb);
1523
1524 /* Try to align data part correctly */
1525 if (hhlen) {
1526 skb->data -= hhlen;
1527 skb->tail -= hhlen;
1528 if (len < hhlen)
1529 skb_reset_network_header(skb);
1530 }
1531 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1532 if (err)
1533 goto out_free;
1534 goto retry;
1535 }
1536
1537 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1538 /* Earlier code assumed this would be a VLAN pkt,
1539 * double-check this now that we have the actual
1540 * packet in hand.
1541 */
1542 struct ethhdr *ehdr;
1543 skb_reset_mac_header(skb);
1544 ehdr = eth_hdr(skb);
1545 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1546 err = -EMSGSIZE;
1547 goto out_unlock;
1548 }
1549 }
1550
1551 skb->protocol = proto;
1552 skb->dev = dev;
1553 skb->priority = sk->sk_priority;
1554 skb->mark = sk->sk_mark;
1555 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1556 if (err < 0)
1557 goto out_unlock;
1558
1559 if (unlikely(extra_len == 4))
1560 skb->no_fcs = 1;
1561
1562 dev_queue_xmit(skb);
1563 rcu_read_unlock();
1564 return len;
1565
1566 out_unlock:
1567 rcu_read_unlock();
1568 out_free:
1569 kfree_skb(skb);
1570 return err;
1571 }
1572
1573 static unsigned int run_filter(const struct sk_buff *skb,
1574 const struct sock *sk,
1575 unsigned int res)
1576 {
1577 struct sk_filter *filter;
1578
1579 rcu_read_lock();
1580 filter = rcu_dereference(sk->sk_filter);
1581 if (filter != NULL)
1582 res = SK_RUN_FILTER(filter, skb);
1583 rcu_read_unlock();
1584
1585 return res;
1586 }
1587
1588 /*
1589 * This function makes lazy skb cloning in hope that most of packets
1590 * are discarded by BPF.
1591 *
1592 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1593 * and skb->cb are mangled. It works because (and until) packets
1594 * falling here are owned by current CPU. Output packets are cloned
1595 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1596 * sequencially, so that if we return skb to original state on exit,
1597 * we will not harm anyone.
1598 */
1599
1600 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1601 struct packet_type *pt, struct net_device *orig_dev)
1602 {
1603 struct sock *sk;
1604 struct sockaddr_ll *sll;
1605 struct packet_sock *po;
1606 u8 *skb_head = skb->data;
1607 int skb_len = skb->len;
1608 unsigned int snaplen, res;
1609
1610 if (skb->pkt_type == PACKET_LOOPBACK)
1611 goto drop;
1612
1613 sk = pt->af_packet_priv;
1614 po = pkt_sk(sk);
1615
1616 if (!net_eq(dev_net(dev), sock_net(sk)))
1617 goto drop;
1618
1619 skb->dev = dev;
1620
1621 if (dev->header_ops) {
1622 /* The device has an explicit notion of ll header,
1623 * exported to higher levels.
1624 *
1625 * Otherwise, the device hides details of its frame
1626 * structure, so that corresponding packet head is
1627 * never delivered to user.
1628 */
1629 if (sk->sk_type != SOCK_DGRAM)
1630 skb_push(skb, skb->data - skb_mac_header(skb));
1631 else if (skb->pkt_type == PACKET_OUTGOING) {
1632 /* Special case: outgoing packets have ll header at head */
1633 skb_pull(skb, skb_network_offset(skb));
1634 }
1635 }
1636
1637 snaplen = skb->len;
1638
1639 res = run_filter(skb, sk, snaplen);
1640 if (!res)
1641 goto drop_n_restore;
1642 if (snaplen > res)
1643 snaplen = res;
1644
1645 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1646 goto drop_n_acct;
1647
1648 if (skb_shared(skb)) {
1649 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1650 if (nskb == NULL)
1651 goto drop_n_acct;
1652
1653 if (skb_head != skb->data) {
1654 skb->data = skb_head;
1655 skb->len = skb_len;
1656 }
1657 kfree_skb(skb);
1658 skb = nskb;
1659 }
1660
1661 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1662 sizeof(skb->cb));
1663
1664 sll = &PACKET_SKB_CB(skb)->sa.ll;
1665 sll->sll_family = AF_PACKET;
1666 sll->sll_hatype = dev->type;
1667 sll->sll_protocol = skb->protocol;
1668 sll->sll_pkttype = skb->pkt_type;
1669 if (unlikely(po->origdev))
1670 sll->sll_ifindex = orig_dev->ifindex;
1671 else
1672 sll->sll_ifindex = dev->ifindex;
1673
1674 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1675
1676 PACKET_SKB_CB(skb)->origlen = skb->len;
1677
1678 if (pskb_trim(skb, snaplen))
1679 goto drop_n_acct;
1680
1681 skb_set_owner_r(skb, sk);
1682 skb->dev = NULL;
1683 skb_dst_drop(skb);
1684
1685 /* drop conntrack reference */
1686 nf_reset(skb);
1687
1688 spin_lock(&sk->sk_receive_queue.lock);
1689 po->stats.tp_packets++;
1690 skb->dropcount = atomic_read(&sk->sk_drops);
1691 __skb_queue_tail(&sk->sk_receive_queue, skb);
1692 spin_unlock(&sk->sk_receive_queue.lock);
1693 sk->sk_data_ready(sk, skb->len);
1694 return 0;
1695
1696 drop_n_acct:
1697 spin_lock(&sk->sk_receive_queue.lock);
1698 po->stats.tp_drops++;
1699 atomic_inc(&sk->sk_drops);
1700 spin_unlock(&sk->sk_receive_queue.lock);
1701
1702 drop_n_restore:
1703 if (skb_head != skb->data && skb_shared(skb)) {
1704 skb->data = skb_head;
1705 skb->len = skb_len;
1706 }
1707 drop:
1708 consume_skb(skb);
1709 return 0;
1710 }
1711
1712 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1713 struct packet_type *pt, struct net_device *orig_dev)
1714 {
1715 struct sock *sk;
1716 struct packet_sock *po;
1717 struct sockaddr_ll *sll;
1718 union {
1719 struct tpacket_hdr *h1;
1720 struct tpacket2_hdr *h2;
1721 struct tpacket3_hdr *h3;
1722 void *raw;
1723 } h;
1724 u8 *skb_head = skb->data;
1725 int skb_len = skb->len;
1726 unsigned int snaplen, res;
1727 unsigned long status = TP_STATUS_USER;
1728 unsigned short macoff, netoff, hdrlen;
1729 struct sk_buff *copy_skb = NULL;
1730 struct timeval tv;
1731 struct timespec ts;
1732 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1733
1734 if (skb->pkt_type == PACKET_LOOPBACK)
1735 goto drop;
1736
1737 sk = pt->af_packet_priv;
1738 po = pkt_sk(sk);
1739
1740 if (!net_eq(dev_net(dev), sock_net(sk)))
1741 goto drop;
1742
1743 if (dev->header_ops) {
1744 if (sk->sk_type != SOCK_DGRAM)
1745 skb_push(skb, skb->data - skb_mac_header(skb));
1746 else if (skb->pkt_type == PACKET_OUTGOING) {
1747 /* Special case: outgoing packets have ll header at head */
1748 skb_pull(skb, skb_network_offset(skb));
1749 }
1750 }
1751
1752 if (skb->ip_summed == CHECKSUM_PARTIAL)
1753 status |= TP_STATUS_CSUMNOTREADY;
1754
1755 snaplen = skb->len;
1756
1757 res = run_filter(skb, sk, snaplen);
1758 if (!res)
1759 goto drop_n_restore;
1760 if (snaplen > res)
1761 snaplen = res;
1762
1763 if (sk->sk_type == SOCK_DGRAM) {
1764 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1765 po->tp_reserve;
1766 } else {
1767 unsigned int maclen = skb_network_offset(skb);
1768 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1769 (maclen < 16 ? 16 : maclen)) +
1770 po->tp_reserve;
1771 macoff = netoff - maclen;
1772 }
1773 if (po->tp_version <= TPACKET_V2) {
1774 if (macoff + snaplen > po->rx_ring.frame_size) {
1775 if (po->copy_thresh &&
1776 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1777 if (skb_shared(skb)) {
1778 copy_skb = skb_clone(skb, GFP_ATOMIC);
1779 } else {
1780 copy_skb = skb_get(skb);
1781 skb_head = skb->data;
1782 }
1783 if (copy_skb)
1784 skb_set_owner_r(copy_skb, sk);
1785 }
1786 snaplen = po->rx_ring.frame_size - macoff;
1787 if ((int)snaplen < 0)
1788 snaplen = 0;
1789 }
1790 }
1791 spin_lock(&sk->sk_receive_queue.lock);
1792 h.raw = packet_current_rx_frame(po, skb,
1793 TP_STATUS_KERNEL, (macoff+snaplen));
1794 if (!h.raw)
1795 goto ring_is_full;
1796 if (po->tp_version <= TPACKET_V2) {
1797 packet_increment_rx_head(po, &po->rx_ring);
1798 /*
1799 * LOSING will be reported till you read the stats,
1800 * because it's COR - Clear On Read.
1801 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1802 * at packet level.
1803 */
1804 if (po->stats.tp_drops)
1805 status |= TP_STATUS_LOSING;
1806 }
1807 po->stats.tp_packets++;
1808 if (copy_skb) {
1809 status |= TP_STATUS_COPY;
1810 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1811 }
1812 spin_unlock(&sk->sk_receive_queue.lock);
1813
1814 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1815
1816 switch (po->tp_version) {
1817 case TPACKET_V1:
1818 h.h1->tp_len = skb->len;
1819 h.h1->tp_snaplen = snaplen;
1820 h.h1->tp_mac = macoff;
1821 h.h1->tp_net = netoff;
1822 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1823 && shhwtstamps->syststamp.tv64)
1824 tv = ktime_to_timeval(shhwtstamps->syststamp);
1825 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1826 && shhwtstamps->hwtstamp.tv64)
1827 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1828 else if (skb->tstamp.tv64)
1829 tv = ktime_to_timeval(skb->tstamp);
1830 else
1831 do_gettimeofday(&tv);
1832 h.h1->tp_sec = tv.tv_sec;
1833 h.h1->tp_usec = tv.tv_usec;
1834 hdrlen = sizeof(*h.h1);
1835 break;
1836 case TPACKET_V2:
1837 h.h2->tp_len = skb->len;
1838 h.h2->tp_snaplen = snaplen;
1839 h.h2->tp_mac = macoff;
1840 h.h2->tp_net = netoff;
1841 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1842 && shhwtstamps->syststamp.tv64)
1843 ts = ktime_to_timespec(shhwtstamps->syststamp);
1844 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1845 && shhwtstamps->hwtstamp.tv64)
1846 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1847 else if (skb->tstamp.tv64)
1848 ts = ktime_to_timespec(skb->tstamp);
1849 else
1850 getnstimeofday(&ts);
1851 h.h2->tp_sec = ts.tv_sec;
1852 h.h2->tp_nsec = ts.tv_nsec;
1853 if (vlan_tx_tag_present(skb)) {
1854 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1855 status |= TP_STATUS_VLAN_VALID;
1856 } else {
1857 h.h2->tp_vlan_tci = 0;
1858 }
1859 h.h2->tp_padding = 0;
1860 hdrlen = sizeof(*h.h2);
1861 break;
1862 case TPACKET_V3:
1863 /* tp_nxt_offset,vlan are already populated above.
1864 * So DONT clear those fields here
1865 */
1866 h.h3->tp_status |= status;
1867 h.h3->tp_len = skb->len;
1868 h.h3->tp_snaplen = snaplen;
1869 h.h3->tp_mac = macoff;
1870 h.h3->tp_net = netoff;
1871 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1872 && shhwtstamps->syststamp.tv64)
1873 ts = ktime_to_timespec(shhwtstamps->syststamp);
1874 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1875 && shhwtstamps->hwtstamp.tv64)
1876 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1877 else if (skb->tstamp.tv64)
1878 ts = ktime_to_timespec(skb->tstamp);
1879 else
1880 getnstimeofday(&ts);
1881 h.h3->tp_sec = ts.tv_sec;
1882 h.h3->tp_nsec = ts.tv_nsec;
1883 hdrlen = sizeof(*h.h3);
1884 break;
1885 default:
1886 BUG();
1887 }
1888
1889 sll = h.raw + TPACKET_ALIGN(hdrlen);
1890 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1891 sll->sll_family = AF_PACKET;
1892 sll->sll_hatype = dev->type;
1893 sll->sll_protocol = skb->protocol;
1894 sll->sll_pkttype = skb->pkt_type;
1895 if (unlikely(po->origdev))
1896 sll->sll_ifindex = orig_dev->ifindex;
1897 else
1898 sll->sll_ifindex = dev->ifindex;
1899
1900 smp_mb();
1901 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1902 {
1903 u8 *start, *end;
1904
1905 if (po->tp_version <= TPACKET_V2) {
1906 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1907 + macoff + snaplen);
1908 for (start = h.raw; start < end; start += PAGE_SIZE)
1909 flush_dcache_page(pgv_to_page(start));
1910 }
1911 smp_wmb();
1912 }
1913 #endif
1914 if (po->tp_version <= TPACKET_V2)
1915 __packet_set_status(po, h.raw, status);
1916 else
1917 prb_clear_blk_fill_status(&po->rx_ring);
1918
1919 sk->sk_data_ready(sk, 0);
1920
1921 drop_n_restore:
1922 if (skb_head != skb->data && skb_shared(skb)) {
1923 skb->data = skb_head;
1924 skb->len = skb_len;
1925 }
1926 drop:
1927 kfree_skb(skb);
1928 return 0;
1929
1930 ring_is_full:
1931 po->stats.tp_drops++;
1932 spin_unlock(&sk->sk_receive_queue.lock);
1933
1934 sk->sk_data_ready(sk, 0);
1935 kfree_skb(copy_skb);
1936 goto drop_n_restore;
1937 }
1938
1939 static void tpacket_destruct_skb(struct sk_buff *skb)
1940 {
1941 struct packet_sock *po = pkt_sk(skb->sk);
1942 void *ph;
1943
1944 if (likely(po->tx_ring.pg_vec)) {
1945 ph = skb_shinfo(skb)->destructor_arg;
1946 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
1947 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1948 atomic_dec(&po->tx_ring.pending);
1949 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1950 }
1951
1952 sock_wfree(skb);
1953 }
1954
1955 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1956 void *frame, struct net_device *dev, int size_max,
1957 __be16 proto, unsigned char *addr, int hlen)
1958 {
1959 union {
1960 struct tpacket_hdr *h1;
1961 struct tpacket2_hdr *h2;
1962 void *raw;
1963 } ph;
1964 int to_write, offset, len, tp_len, nr_frags, len_max;
1965 struct socket *sock = po->sk.sk_socket;
1966 struct page *page;
1967 void *data;
1968 int err;
1969
1970 ph.raw = frame;
1971
1972 skb->protocol = proto;
1973 skb->dev = dev;
1974 skb->priority = po->sk.sk_priority;
1975 skb->mark = po->sk.sk_mark;
1976 skb_shinfo(skb)->destructor_arg = ph.raw;
1977
1978 switch (po->tp_version) {
1979 case TPACKET_V2:
1980 tp_len = ph.h2->tp_len;
1981 break;
1982 default:
1983 tp_len = ph.h1->tp_len;
1984 break;
1985 }
1986 if (unlikely(tp_len > size_max)) {
1987 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1988 return -EMSGSIZE;
1989 }
1990
1991 skb_reserve(skb, hlen);
1992 skb_reset_network_header(skb);
1993
1994 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1995 to_write = tp_len;
1996
1997 if (sock->type == SOCK_DGRAM) {
1998 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1999 NULL, tp_len);
2000 if (unlikely(err < 0))
2001 return -EINVAL;
2002 } else if (dev->hard_header_len) {
2003 /* net device doesn't like empty head */
2004 if (unlikely(tp_len <= dev->hard_header_len)) {
2005 pr_err("packet size is too short (%d < %d)\n",
2006 tp_len, dev->hard_header_len);
2007 return -EINVAL;
2008 }
2009
2010 skb_push(skb, dev->hard_header_len);
2011 err = skb_store_bits(skb, 0, data,
2012 dev->hard_header_len);
2013 if (unlikely(err))
2014 return err;
2015
2016 data += dev->hard_header_len;
2017 to_write -= dev->hard_header_len;
2018 }
2019
2020 err = -EFAULT;
2021 offset = offset_in_page(data);
2022 len_max = PAGE_SIZE - offset;
2023 len = ((to_write > len_max) ? len_max : to_write);
2024
2025 skb->data_len = to_write;
2026 skb->len += to_write;
2027 skb->truesize += to_write;
2028 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2029
2030 while (likely(to_write)) {
2031 nr_frags = skb_shinfo(skb)->nr_frags;
2032
2033 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2034 pr_err("Packet exceed the number of skb frags(%lu)\n",
2035 MAX_SKB_FRAGS);
2036 return -EFAULT;
2037 }
2038
2039 page = pgv_to_page(data);
2040 data += len;
2041 flush_dcache_page(page);
2042 get_page(page);
2043 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2044 to_write -= len;
2045 offset = 0;
2046 len_max = PAGE_SIZE;
2047 len = ((to_write > len_max) ? len_max : to_write);
2048 }
2049
2050 return tp_len;
2051 }
2052
2053 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2054 {
2055 struct sk_buff *skb;
2056 struct net_device *dev;
2057 __be16 proto;
2058 bool need_rls_dev = false;
2059 int err, reserve = 0;
2060 void *ph;
2061 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2062 int tp_len, size_max;
2063 unsigned char *addr;
2064 int len_sum = 0;
2065 int status = 0;
2066 int hlen, tlen;
2067
2068 mutex_lock(&po->pg_vec_lock);
2069
2070 err = -EBUSY;
2071 if (saddr == NULL) {
2072 dev = po->prot_hook.dev;
2073 proto = po->num;
2074 addr = NULL;
2075 } else {
2076 err = -EINVAL;
2077 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2078 goto out;
2079 if (msg->msg_namelen < (saddr->sll_halen
2080 + offsetof(struct sockaddr_ll,
2081 sll_addr)))
2082 goto out;
2083 proto = saddr->sll_protocol;
2084 addr = saddr->sll_addr;
2085 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2086 need_rls_dev = true;
2087 }
2088
2089 err = -ENXIO;
2090 if (unlikely(dev == NULL))
2091 goto out;
2092
2093 reserve = dev->hard_header_len;
2094
2095 err = -ENETDOWN;
2096 if (unlikely(!(dev->flags & IFF_UP)))
2097 goto out_put;
2098
2099 size_max = po->tx_ring.frame_size
2100 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2101
2102 if (size_max > dev->mtu + reserve)
2103 size_max = dev->mtu + reserve;
2104
2105 do {
2106 ph = packet_current_frame(po, &po->tx_ring,
2107 TP_STATUS_SEND_REQUEST);
2108
2109 if (unlikely(ph == NULL)) {
2110 schedule();
2111 continue;
2112 }
2113
2114 status = TP_STATUS_SEND_REQUEST;
2115 hlen = LL_RESERVED_SPACE(dev);
2116 tlen = dev->needed_tailroom;
2117 skb = sock_alloc_send_skb(&po->sk,
2118 hlen + tlen + sizeof(struct sockaddr_ll),
2119 0, &err);
2120
2121 if (unlikely(skb == NULL))
2122 goto out_status;
2123
2124 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2125 addr, hlen);
2126
2127 if (unlikely(tp_len < 0)) {
2128 if (po->tp_loss) {
2129 __packet_set_status(po, ph,
2130 TP_STATUS_AVAILABLE);
2131 packet_increment_head(&po->tx_ring);
2132 kfree_skb(skb);
2133 continue;
2134 } else {
2135 status = TP_STATUS_WRONG_FORMAT;
2136 err = tp_len;
2137 goto out_status;
2138 }
2139 }
2140
2141 skb->destructor = tpacket_destruct_skb;
2142 __packet_set_status(po, ph, TP_STATUS_SENDING);
2143 atomic_inc(&po->tx_ring.pending);
2144
2145 status = TP_STATUS_SEND_REQUEST;
2146 err = dev_queue_xmit(skb);
2147 if (unlikely(err > 0)) {
2148 err = net_xmit_errno(err);
2149 if (err && __packet_get_status(po, ph) ==
2150 TP_STATUS_AVAILABLE) {
2151 /* skb was destructed already */
2152 skb = NULL;
2153 goto out_status;
2154 }
2155 /*
2156 * skb was dropped but not destructed yet;
2157 * let's treat it like congestion or err < 0
2158 */
2159 err = 0;
2160 }
2161 packet_increment_head(&po->tx_ring);
2162 len_sum += tp_len;
2163 } while (likely((ph != NULL) ||
2164 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2165 (atomic_read(&po->tx_ring.pending))))
2166 );
2167
2168 err = len_sum;
2169 goto out_put;
2170
2171 out_status:
2172 __packet_set_status(po, ph, status);
2173 kfree_skb(skb);
2174 out_put:
2175 if (need_rls_dev)
2176 dev_put(dev);
2177 out:
2178 mutex_unlock(&po->pg_vec_lock);
2179 return err;
2180 }
2181
2182 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2183 size_t reserve, size_t len,
2184 size_t linear, int noblock,
2185 int *err)
2186 {
2187 struct sk_buff *skb;
2188
2189 /* Under a page? Don't bother with paged skb. */
2190 if (prepad + len < PAGE_SIZE || !linear)
2191 linear = len;
2192
2193 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2194 err);
2195 if (!skb)
2196 return NULL;
2197
2198 skb_reserve(skb, reserve);
2199 skb_put(skb, linear);
2200 skb->data_len = len - linear;
2201 skb->len += len - linear;
2202
2203 return skb;
2204 }
2205
2206 static int packet_snd(struct socket *sock,
2207 struct msghdr *msg, size_t len)
2208 {
2209 struct sock *sk = sock->sk;
2210 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2211 struct sk_buff *skb;
2212 struct net_device *dev;
2213 __be16 proto;
2214 bool need_rls_dev = false;
2215 unsigned char *addr;
2216 int err, reserve = 0;
2217 struct virtio_net_hdr vnet_hdr = { 0 };
2218 int offset = 0;
2219 int vnet_hdr_len;
2220 struct packet_sock *po = pkt_sk(sk);
2221 unsigned short gso_type = 0;
2222 int hlen, tlen;
2223 int extra_len = 0;
2224
2225 /*
2226 * Get and verify the address.
2227 */
2228
2229 if (saddr == NULL) {
2230 dev = po->prot_hook.dev;
2231 proto = po->num;
2232 addr = NULL;
2233 } else {
2234 err = -EINVAL;
2235 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2236 goto out;
2237 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2238 goto out;
2239 proto = saddr->sll_protocol;
2240 addr = saddr->sll_addr;
2241 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2242 need_rls_dev = true;
2243 }
2244
2245 err = -ENXIO;
2246 if (dev == NULL)
2247 goto out_unlock;
2248 if (sock->type == SOCK_RAW)
2249 reserve = dev->hard_header_len;
2250
2251 err = -ENETDOWN;
2252 if (!(dev->flags & IFF_UP))
2253 goto out_unlock;
2254
2255 if (po->has_vnet_hdr) {
2256 vnet_hdr_len = sizeof(vnet_hdr);
2257
2258 err = -EINVAL;
2259 if (len < vnet_hdr_len)
2260 goto out_unlock;
2261
2262 len -= vnet_hdr_len;
2263
2264 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2265 vnet_hdr_len);
2266 if (err < 0)
2267 goto out_unlock;
2268
2269 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2270 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2271 vnet_hdr.hdr_len))
2272 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2273 vnet_hdr.csum_offset + 2;
2274
2275 err = -EINVAL;
2276 if (vnet_hdr.hdr_len > len)
2277 goto out_unlock;
2278
2279 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2280 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2281 case VIRTIO_NET_HDR_GSO_TCPV4:
2282 gso_type = SKB_GSO_TCPV4;
2283 break;
2284 case VIRTIO_NET_HDR_GSO_TCPV6:
2285 gso_type = SKB_GSO_TCPV6;
2286 break;
2287 case VIRTIO_NET_HDR_GSO_UDP:
2288 gso_type = SKB_GSO_UDP;
2289 break;
2290 default:
2291 goto out_unlock;
2292 }
2293
2294 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2295 gso_type |= SKB_GSO_TCP_ECN;
2296
2297 if (vnet_hdr.gso_size == 0)
2298 goto out_unlock;
2299
2300 }
2301 }
2302
2303 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2304 if (!netif_supports_nofcs(dev)) {
2305 err = -EPROTONOSUPPORT;
2306 goto out_unlock;
2307 }
2308 extra_len = 4; /* We're doing our own CRC */
2309 }
2310
2311 err = -EMSGSIZE;
2312 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2313 goto out_unlock;
2314
2315 err = -ENOBUFS;
2316 hlen = LL_RESERVED_SPACE(dev);
2317 tlen = dev->needed_tailroom;
2318 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2319 msg->msg_flags & MSG_DONTWAIT, &err);
2320 if (skb == NULL)
2321 goto out_unlock;
2322
2323 skb_set_network_header(skb, reserve);
2324
2325 err = -EINVAL;
2326 if (sock->type == SOCK_DGRAM &&
2327 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2328 goto out_free;
2329
2330 /* Returns -EFAULT on error */
2331 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2332 if (err)
2333 goto out_free;
2334 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2335 if (err < 0)
2336 goto out_free;
2337
2338 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2339 /* Earlier code assumed this would be a VLAN pkt,
2340 * double-check this now that we have the actual
2341 * packet in hand.
2342 */
2343 struct ethhdr *ehdr;
2344 skb_reset_mac_header(skb);
2345 ehdr = eth_hdr(skb);
2346 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2347 err = -EMSGSIZE;
2348 goto out_free;
2349 }
2350 }
2351
2352 skb->protocol = proto;
2353 skb->dev = dev;
2354 skb->priority = sk->sk_priority;
2355 skb->mark = sk->sk_mark;
2356
2357 if (po->has_vnet_hdr) {
2358 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2359 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2360 vnet_hdr.csum_offset)) {
2361 err = -EINVAL;
2362 goto out_free;
2363 }
2364 }
2365
2366 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2367 skb_shinfo(skb)->gso_type = gso_type;
2368
2369 /* Header must be checked, and gso_segs computed. */
2370 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2371 skb_shinfo(skb)->gso_segs = 0;
2372
2373 len += vnet_hdr_len;
2374 }
2375
2376 if (unlikely(extra_len == 4))
2377 skb->no_fcs = 1;
2378
2379 /*
2380 * Now send it
2381 */
2382
2383 err = dev_queue_xmit(skb);
2384 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2385 goto out_unlock;
2386
2387 if (need_rls_dev)
2388 dev_put(dev);
2389
2390 return len;
2391
2392 out_free:
2393 kfree_skb(skb);
2394 out_unlock:
2395 if (dev && need_rls_dev)
2396 dev_put(dev);
2397 out:
2398 return err;
2399 }
2400
2401 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2402 struct msghdr *msg, size_t len)
2403 {
2404 struct sock *sk = sock->sk;
2405 struct packet_sock *po = pkt_sk(sk);
2406 if (po->tx_ring.pg_vec)
2407 return tpacket_snd(po, msg);
2408 else
2409 return packet_snd(sock, msg, len);
2410 }
2411
2412 /*
2413 * Close a PACKET socket. This is fairly simple. We immediately go
2414 * to 'closed' state and remove our protocol entry in the device list.
2415 */
2416
2417 static int packet_release(struct socket *sock)
2418 {
2419 struct sock *sk = sock->sk;
2420 struct packet_sock *po;
2421 struct net *net;
2422 union tpacket_req_u req_u;
2423
2424 if (!sk)
2425 return 0;
2426
2427 net = sock_net(sk);
2428 po = pkt_sk(sk);
2429
2430 spin_lock_bh(&net->packet.sklist_lock);
2431 sk_del_node_init_rcu(sk);
2432 sock_prot_inuse_add(net, sk->sk_prot, -1);
2433 spin_unlock_bh(&net->packet.sklist_lock);
2434
2435 spin_lock(&po->bind_lock);
2436 unregister_prot_hook(sk, false);
2437 if (po->prot_hook.dev) {
2438 dev_put(po->prot_hook.dev);
2439 po->prot_hook.dev = NULL;
2440 }
2441 spin_unlock(&po->bind_lock);
2442
2443 packet_flush_mclist(sk);
2444
2445 memset(&req_u, 0, sizeof(req_u));
2446
2447 if (po->rx_ring.pg_vec)
2448 packet_set_ring(sk, &req_u, 1, 0);
2449
2450 if (po->tx_ring.pg_vec)
2451 packet_set_ring(sk, &req_u, 1, 1);
2452
2453 fanout_release(sk);
2454
2455 synchronize_net();
2456 /*
2457 * Now the socket is dead. No more input will appear.
2458 */
2459 sock_orphan(sk);
2460 sock->sk = NULL;
2461
2462 /* Purge queues */
2463
2464 skb_queue_purge(&sk->sk_receive_queue);
2465 sk_refcnt_debug_release(sk);
2466
2467 sock_put(sk);
2468 return 0;
2469 }
2470
2471 /*
2472 * Attach a packet hook.
2473 */
2474
2475 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2476 {
2477 struct packet_sock *po = pkt_sk(sk);
2478
2479 if (po->fanout) {
2480 if (dev)
2481 dev_put(dev);
2482
2483 return -EINVAL;
2484 }
2485
2486 lock_sock(sk);
2487
2488 spin_lock(&po->bind_lock);
2489 unregister_prot_hook(sk, true);
2490 po->num = protocol;
2491 po->prot_hook.type = protocol;
2492 if (po->prot_hook.dev)
2493 dev_put(po->prot_hook.dev);
2494 po->prot_hook.dev = dev;
2495
2496 po->ifindex = dev ? dev->ifindex : 0;
2497
2498 if (protocol == 0)
2499 goto out_unlock;
2500
2501 if (!dev || (dev->flags & IFF_UP)) {
2502 register_prot_hook(sk);
2503 } else {
2504 sk->sk_err = ENETDOWN;
2505 if (!sock_flag(sk, SOCK_DEAD))
2506 sk->sk_error_report(sk);
2507 }
2508
2509 out_unlock:
2510 spin_unlock(&po->bind_lock);
2511 release_sock(sk);
2512 return 0;
2513 }
2514
2515 /*
2516 * Bind a packet socket to a device
2517 */
2518
2519 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2520 int addr_len)
2521 {
2522 struct sock *sk = sock->sk;
2523 char name[15];
2524 struct net_device *dev;
2525 int err = -ENODEV;
2526
2527 /*
2528 * Check legality
2529 */
2530
2531 if (addr_len != sizeof(struct sockaddr))
2532 return -EINVAL;
2533 strlcpy(name, uaddr->sa_data, sizeof(name));
2534
2535 dev = dev_get_by_name(sock_net(sk), name);
2536 if (dev)
2537 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2538 return err;
2539 }
2540
2541 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2542 {
2543 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2544 struct sock *sk = sock->sk;
2545 struct net_device *dev = NULL;
2546 int err;
2547
2548
2549 /*
2550 * Check legality
2551 */
2552
2553 if (addr_len < sizeof(struct sockaddr_ll))
2554 return -EINVAL;
2555 if (sll->sll_family != AF_PACKET)
2556 return -EINVAL;
2557
2558 if (sll->sll_ifindex) {
2559 err = -ENODEV;
2560 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2561 if (dev == NULL)
2562 goto out;
2563 }
2564 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2565
2566 out:
2567 return err;
2568 }
2569
2570 static struct proto packet_proto = {
2571 .name = "PACKET",
2572 .owner = THIS_MODULE,
2573 .obj_size = sizeof(struct packet_sock),
2574 };
2575
2576 /*
2577 * Create a packet of type SOCK_PACKET.
2578 */
2579
2580 static int packet_create(struct net *net, struct socket *sock, int protocol,
2581 int kern)
2582 {
2583 struct sock *sk;
2584 struct packet_sock *po;
2585 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2586 int err;
2587
2588 if (!capable(CAP_NET_RAW))
2589 return -EPERM;
2590 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2591 sock->type != SOCK_PACKET)
2592 return -ESOCKTNOSUPPORT;
2593
2594 sock->state = SS_UNCONNECTED;
2595
2596 err = -ENOBUFS;
2597 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2598 if (sk == NULL)
2599 goto out;
2600
2601 sock->ops = &packet_ops;
2602 if (sock->type == SOCK_PACKET)
2603 sock->ops = &packet_ops_spkt;
2604
2605 sock_init_data(sock, sk);
2606
2607 po = pkt_sk(sk);
2608 sk->sk_family = PF_PACKET;
2609 po->num = proto;
2610
2611 sk->sk_destruct = packet_sock_destruct;
2612 sk_refcnt_debug_inc(sk);
2613
2614 /*
2615 * Attach a protocol block
2616 */
2617
2618 spin_lock_init(&po->bind_lock);
2619 mutex_init(&po->pg_vec_lock);
2620 po->prot_hook.func = packet_rcv;
2621
2622 if (sock->type == SOCK_PACKET)
2623 po->prot_hook.func = packet_rcv_spkt;
2624
2625 po->prot_hook.af_packet_priv = sk;
2626
2627 if (proto) {
2628 po->prot_hook.type = proto;
2629 register_prot_hook(sk);
2630 }
2631
2632 spin_lock_bh(&net->packet.sklist_lock);
2633 sk_add_node_rcu(sk, &net->packet.sklist);
2634 sock_prot_inuse_add(net, &packet_proto, 1);
2635 spin_unlock_bh(&net->packet.sklist_lock);
2636
2637 return 0;
2638 out:
2639 return err;
2640 }
2641
2642 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2643 {
2644 struct sock_exterr_skb *serr;
2645 struct sk_buff *skb, *skb2;
2646 int copied, err;
2647
2648 err = -EAGAIN;
2649 skb = skb_dequeue(&sk->sk_error_queue);
2650 if (skb == NULL)
2651 goto out;
2652
2653 copied = skb->len;
2654 if (copied > len) {
2655 msg->msg_flags |= MSG_TRUNC;
2656 copied = len;
2657 }
2658 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2659 if (err)
2660 goto out_free_skb;
2661
2662 sock_recv_timestamp(msg, sk, skb);
2663
2664 serr = SKB_EXT_ERR(skb);
2665 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2666 sizeof(serr->ee), &serr->ee);
2667
2668 msg->msg_flags |= MSG_ERRQUEUE;
2669 err = copied;
2670
2671 /* Reset and regenerate socket error */
2672 spin_lock_bh(&sk->sk_error_queue.lock);
2673 sk->sk_err = 0;
2674 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2675 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2676 spin_unlock_bh(&sk->sk_error_queue.lock);
2677 sk->sk_error_report(sk);
2678 } else
2679 spin_unlock_bh(&sk->sk_error_queue.lock);
2680
2681 out_free_skb:
2682 kfree_skb(skb);
2683 out:
2684 return err;
2685 }
2686
2687 /*
2688 * Pull a packet from our receive queue and hand it to the user.
2689 * If necessary we block.
2690 */
2691
2692 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2693 struct msghdr *msg, size_t len, int flags)
2694 {
2695 struct sock *sk = sock->sk;
2696 struct sk_buff *skb;
2697 int copied, err;
2698 struct sockaddr_ll *sll;
2699 int vnet_hdr_len = 0;
2700
2701 err = -EINVAL;
2702 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2703 goto out;
2704
2705 #if 0
2706 /* What error should we return now? EUNATTACH? */
2707 if (pkt_sk(sk)->ifindex < 0)
2708 return -ENODEV;
2709 #endif
2710
2711 if (flags & MSG_ERRQUEUE) {
2712 err = packet_recv_error(sk, msg, len);
2713 goto out;
2714 }
2715
2716 /*
2717 * Call the generic datagram receiver. This handles all sorts
2718 * of horrible races and re-entrancy so we can forget about it
2719 * in the protocol layers.
2720 *
2721 * Now it will return ENETDOWN, if device have just gone down,
2722 * but then it will block.
2723 */
2724
2725 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2726
2727 /*
2728 * An error occurred so return it. Because skb_recv_datagram()
2729 * handles the blocking we don't see and worry about blocking
2730 * retries.
2731 */
2732
2733 if (skb == NULL)
2734 goto out;
2735
2736 if (pkt_sk(sk)->has_vnet_hdr) {
2737 struct virtio_net_hdr vnet_hdr = { 0 };
2738
2739 err = -EINVAL;
2740 vnet_hdr_len = sizeof(vnet_hdr);
2741 if (len < vnet_hdr_len)
2742 goto out_free;
2743
2744 len -= vnet_hdr_len;
2745
2746 if (skb_is_gso(skb)) {
2747 struct skb_shared_info *sinfo = skb_shinfo(skb);
2748
2749 /* This is a hint as to how much should be linear. */
2750 vnet_hdr.hdr_len = skb_headlen(skb);
2751 vnet_hdr.gso_size = sinfo->gso_size;
2752 if (sinfo->gso_type & SKB_GSO_TCPV4)
2753 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2754 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2755 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2756 else if (sinfo->gso_type & SKB_GSO_UDP)
2757 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2758 else if (sinfo->gso_type & SKB_GSO_FCOE)
2759 goto out_free;
2760 else
2761 BUG();
2762 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2763 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2764 } else
2765 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2766
2767 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2768 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2769 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2770 vnet_hdr.csum_offset = skb->csum_offset;
2771 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2772 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2773 } /* else everything is zero */
2774
2775 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2776 vnet_hdr_len);
2777 if (err < 0)
2778 goto out_free;
2779 }
2780
2781 /*
2782 * If the address length field is there to be filled in, we fill
2783 * it in now.
2784 */
2785
2786 sll = &PACKET_SKB_CB(skb)->sa.ll;
2787 if (sock->type == SOCK_PACKET)
2788 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2789 else
2790 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2791
2792 /*
2793 * You lose any data beyond the buffer you gave. If it worries a
2794 * user program they can ask the device for its MTU anyway.
2795 */
2796
2797 copied = skb->len;
2798 if (copied > len) {
2799 copied = len;
2800 msg->msg_flags |= MSG_TRUNC;
2801 }
2802
2803 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2804 if (err)
2805 goto out_free;
2806
2807 sock_recv_ts_and_drops(msg, sk, skb);
2808
2809 if (msg->msg_name)
2810 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2811 msg->msg_namelen);
2812
2813 if (pkt_sk(sk)->auxdata) {
2814 struct tpacket_auxdata aux;
2815
2816 aux.tp_status = TP_STATUS_USER;
2817 if (skb->ip_summed == CHECKSUM_PARTIAL)
2818 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2819 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2820 aux.tp_snaplen = skb->len;
2821 aux.tp_mac = 0;
2822 aux.tp_net = skb_network_offset(skb);
2823 if (vlan_tx_tag_present(skb)) {
2824 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2825 aux.tp_status |= TP_STATUS_VLAN_VALID;
2826 } else {
2827 aux.tp_vlan_tci = 0;
2828 }
2829 aux.tp_padding = 0;
2830 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2831 }
2832
2833 /*
2834 * Free or return the buffer as appropriate. Again this
2835 * hides all the races and re-entrancy issues from us.
2836 */
2837 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2838
2839 out_free:
2840 skb_free_datagram(sk, skb);
2841 out:
2842 return err;
2843 }
2844
2845 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2846 int *uaddr_len, int peer)
2847 {
2848 struct net_device *dev;
2849 struct sock *sk = sock->sk;
2850
2851 if (peer)
2852 return -EOPNOTSUPP;
2853
2854 uaddr->sa_family = AF_PACKET;
2855 rcu_read_lock();
2856 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2857 if (dev)
2858 strncpy(uaddr->sa_data, dev->name, 14);
2859 else
2860 memset(uaddr->sa_data, 0, 14);
2861 rcu_read_unlock();
2862 *uaddr_len = sizeof(*uaddr);
2863
2864 return 0;
2865 }
2866
2867 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2868 int *uaddr_len, int peer)
2869 {
2870 struct net_device *dev;
2871 struct sock *sk = sock->sk;
2872 struct packet_sock *po = pkt_sk(sk);
2873 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2874
2875 if (peer)
2876 return -EOPNOTSUPP;
2877
2878 sll->sll_family = AF_PACKET;
2879 sll->sll_ifindex = po->ifindex;
2880 sll->sll_protocol = po->num;
2881 sll->sll_pkttype = 0;
2882 rcu_read_lock();
2883 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2884 if (dev) {
2885 sll->sll_hatype = dev->type;
2886 sll->sll_halen = dev->addr_len;
2887 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2888 } else {
2889 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2890 sll->sll_halen = 0;
2891 }
2892 rcu_read_unlock();
2893 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2894
2895 return 0;
2896 }
2897
2898 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2899 int what)
2900 {
2901 switch (i->type) {
2902 case PACKET_MR_MULTICAST:
2903 if (i->alen != dev->addr_len)
2904 return -EINVAL;
2905 if (what > 0)
2906 return dev_mc_add(dev, i->addr);
2907 else
2908 return dev_mc_del(dev, i->addr);
2909 break;
2910 case PACKET_MR_PROMISC:
2911 return dev_set_promiscuity(dev, what);
2912 break;
2913 case PACKET_MR_ALLMULTI:
2914 return dev_set_allmulti(dev, what);
2915 break;
2916 case PACKET_MR_UNICAST:
2917 if (i->alen != dev->addr_len)
2918 return -EINVAL;
2919 if (what > 0)
2920 return dev_uc_add(dev, i->addr);
2921 else
2922 return dev_uc_del(dev, i->addr);
2923 break;
2924 default:
2925 break;
2926 }
2927 return 0;
2928 }
2929
2930 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2931 {
2932 for ( ; i; i = i->next) {
2933 if (i->ifindex == dev->ifindex)
2934 packet_dev_mc(dev, i, what);
2935 }
2936 }
2937
2938 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2939 {
2940 struct packet_sock *po = pkt_sk(sk);
2941 struct packet_mclist *ml, *i;
2942 struct net_device *dev;
2943 int err;
2944
2945 rtnl_lock();
2946
2947 err = -ENODEV;
2948 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2949 if (!dev)
2950 goto done;
2951
2952 err = -EINVAL;
2953 if (mreq->mr_alen > dev->addr_len)
2954 goto done;
2955
2956 err = -ENOBUFS;
2957 i = kmalloc(sizeof(*i), GFP_KERNEL);
2958 if (i == NULL)
2959 goto done;
2960
2961 err = 0;
2962 for (ml = po->mclist; ml; ml = ml->next) {
2963 if (ml->ifindex == mreq->mr_ifindex &&
2964 ml->type == mreq->mr_type &&
2965 ml->alen == mreq->mr_alen &&
2966 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2967 ml->count++;
2968 /* Free the new element ... */
2969 kfree(i);
2970 goto done;
2971 }
2972 }
2973
2974 i->type = mreq->mr_type;
2975 i->ifindex = mreq->mr_ifindex;
2976 i->alen = mreq->mr_alen;
2977 memcpy(i->addr, mreq->mr_address, i->alen);
2978 i->count = 1;
2979 i->next = po->mclist;
2980 po->mclist = i;
2981 err = packet_dev_mc(dev, i, 1);
2982 if (err) {
2983 po->mclist = i->next;
2984 kfree(i);
2985 }
2986
2987 done:
2988 rtnl_unlock();
2989 return err;
2990 }
2991
2992 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2993 {
2994 struct packet_mclist *ml, **mlp;
2995
2996 rtnl_lock();
2997
2998 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2999 if (ml->ifindex == mreq->mr_ifindex &&
3000 ml->type == mreq->mr_type &&
3001 ml->alen == mreq->mr_alen &&
3002 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3003 if (--ml->count == 0) {
3004 struct net_device *dev;
3005 *mlp = ml->next;
3006 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3007 if (dev)
3008 packet_dev_mc(dev, ml, -1);
3009 kfree(ml);
3010 }
3011 rtnl_unlock();
3012 return 0;
3013 }
3014 }
3015 rtnl_unlock();
3016 return -EADDRNOTAVAIL;
3017 }
3018
3019 static void packet_flush_mclist(struct sock *sk)
3020 {
3021 struct packet_sock *po = pkt_sk(sk);
3022 struct packet_mclist *ml;
3023
3024 if (!po->mclist)
3025 return;
3026
3027 rtnl_lock();
3028 while ((ml = po->mclist) != NULL) {
3029 struct net_device *dev;
3030
3031 po->mclist = ml->next;
3032 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3033 if (dev != NULL)
3034 packet_dev_mc(dev, ml, -1);
3035 kfree(ml);
3036 }
3037 rtnl_unlock();
3038 }
3039
3040 static int
3041 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3042 {
3043 struct sock *sk = sock->sk;
3044 struct packet_sock *po = pkt_sk(sk);
3045 int ret;
3046
3047 if (level != SOL_PACKET)
3048 return -ENOPROTOOPT;
3049
3050 switch (optname) {
3051 case PACKET_ADD_MEMBERSHIP:
3052 case PACKET_DROP_MEMBERSHIP:
3053 {
3054 struct packet_mreq_max mreq;
3055 int len = optlen;
3056 memset(&mreq, 0, sizeof(mreq));
3057 if (len < sizeof(struct packet_mreq))
3058 return -EINVAL;
3059 if (len > sizeof(mreq))
3060 len = sizeof(mreq);
3061 if (copy_from_user(&mreq, optval, len))
3062 return -EFAULT;
3063 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3064 return -EINVAL;
3065 if (optname == PACKET_ADD_MEMBERSHIP)
3066 ret = packet_mc_add(sk, &mreq);
3067 else
3068 ret = packet_mc_drop(sk, &mreq);
3069 return ret;
3070 }
3071
3072 case PACKET_RX_RING:
3073 case PACKET_TX_RING:
3074 {
3075 union tpacket_req_u req_u;
3076 int len;
3077
3078 switch (po->tp_version) {
3079 case TPACKET_V1:
3080 case TPACKET_V2:
3081 len = sizeof(req_u.req);
3082 break;
3083 case TPACKET_V3:
3084 default:
3085 len = sizeof(req_u.req3);
3086 break;
3087 }
3088 if (optlen < len)
3089 return -EINVAL;
3090 if (pkt_sk(sk)->has_vnet_hdr)
3091 return -EINVAL;
3092 if (copy_from_user(&req_u.req, optval, len))
3093 return -EFAULT;
3094 return packet_set_ring(sk, &req_u, 0,
3095 optname == PACKET_TX_RING);
3096 }
3097 case PACKET_COPY_THRESH:
3098 {
3099 int val;
3100
3101 if (optlen != sizeof(val))
3102 return -EINVAL;
3103 if (copy_from_user(&val, optval, sizeof(val)))
3104 return -EFAULT;
3105
3106 pkt_sk(sk)->copy_thresh = val;
3107 return 0;
3108 }
3109 case PACKET_VERSION:
3110 {
3111 int val;
3112
3113 if (optlen != sizeof(val))
3114 return -EINVAL;
3115 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3116 return -EBUSY;
3117 if (copy_from_user(&val, optval, sizeof(val)))
3118 return -EFAULT;
3119 switch (val) {
3120 case TPACKET_V1:
3121 case TPACKET_V2:
3122 case TPACKET_V3:
3123 po->tp_version = val;
3124 return 0;
3125 default:
3126 return -EINVAL;
3127 }
3128 }
3129 case PACKET_RESERVE:
3130 {
3131 unsigned int val;
3132
3133 if (optlen != sizeof(val))
3134 return -EINVAL;
3135 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3136 return -EBUSY;
3137 if (copy_from_user(&val, optval, sizeof(val)))
3138 return -EFAULT;
3139 po->tp_reserve = val;
3140 return 0;
3141 }
3142 case PACKET_LOSS:
3143 {
3144 unsigned int val;
3145
3146 if (optlen != sizeof(val))
3147 return -EINVAL;
3148 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3149 return -EBUSY;
3150 if (copy_from_user(&val, optval, sizeof(val)))
3151 return -EFAULT;
3152 po->tp_loss = !!val;
3153 return 0;
3154 }
3155 case PACKET_AUXDATA:
3156 {
3157 int val;
3158
3159 if (optlen < sizeof(val))
3160 return -EINVAL;
3161 if (copy_from_user(&val, optval, sizeof(val)))
3162 return -EFAULT;
3163
3164 po->auxdata = !!val;
3165 return 0;
3166 }
3167 case PACKET_ORIGDEV:
3168 {
3169 int val;
3170
3171 if (optlen < sizeof(val))
3172 return -EINVAL;
3173 if (copy_from_user(&val, optval, sizeof(val)))
3174 return -EFAULT;
3175
3176 po->origdev = !!val;
3177 return 0;
3178 }
3179 case PACKET_VNET_HDR:
3180 {
3181 int val;
3182
3183 if (sock->type != SOCK_RAW)
3184 return -EINVAL;
3185 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3186 return -EBUSY;
3187 if (optlen < sizeof(val))
3188 return -EINVAL;
3189 if (copy_from_user(&val, optval, sizeof(val)))
3190 return -EFAULT;
3191
3192 po->has_vnet_hdr = !!val;
3193 return 0;
3194 }
3195 case PACKET_TIMESTAMP:
3196 {
3197 int val;
3198
3199 if (optlen != sizeof(val))
3200 return -EINVAL;
3201 if (copy_from_user(&val, optval, sizeof(val)))
3202 return -EFAULT;
3203
3204 po->tp_tstamp = val;
3205 return 0;
3206 }
3207 case PACKET_FANOUT:
3208 {
3209 int val;
3210
3211 if (optlen != sizeof(val))
3212 return -EINVAL;
3213 if (copy_from_user(&val, optval, sizeof(val)))
3214 return -EFAULT;
3215
3216 return fanout_add(sk, val & 0xffff, val >> 16);
3217 }
3218 default:
3219 return -ENOPROTOOPT;
3220 }
3221 }
3222
3223 static int packet_getsockopt(struct socket *sock, int level, int optname,
3224 char __user *optval, int __user *optlen)
3225 {
3226 int len;
3227 int val;
3228 struct sock *sk = sock->sk;
3229 struct packet_sock *po = pkt_sk(sk);
3230 void *data;
3231 struct tpacket_stats st;
3232 union tpacket_stats_u st_u;
3233
3234 if (level != SOL_PACKET)
3235 return -ENOPROTOOPT;
3236
3237 if (get_user(len, optlen))
3238 return -EFAULT;
3239
3240 if (len < 0)
3241 return -EINVAL;
3242
3243 switch (optname) {
3244 case PACKET_STATISTICS:
3245 if (po->tp_version == TPACKET_V3) {
3246 len = sizeof(struct tpacket_stats_v3);
3247 } else {
3248 if (len > sizeof(struct tpacket_stats))
3249 len = sizeof(struct tpacket_stats);
3250 }
3251 spin_lock_bh(&sk->sk_receive_queue.lock);
3252 if (po->tp_version == TPACKET_V3) {
3253 memcpy(&st_u.stats3, &po->stats,
3254 sizeof(struct tpacket_stats));
3255 st_u.stats3.tp_freeze_q_cnt =
3256 po->stats_u.stats3.tp_freeze_q_cnt;
3257 st_u.stats3.tp_packets += po->stats.tp_drops;
3258 data = &st_u.stats3;
3259 } else {
3260 st = po->stats;
3261 st.tp_packets += st.tp_drops;
3262 data = &st;
3263 }
3264 memset(&po->stats, 0, sizeof(st));
3265 spin_unlock_bh(&sk->sk_receive_queue.lock);
3266 break;
3267 case PACKET_AUXDATA:
3268 if (len > sizeof(int))
3269 len = sizeof(int);
3270 val = po->auxdata;
3271
3272 data = &val;
3273 break;
3274 case PACKET_ORIGDEV:
3275 if (len > sizeof(int))
3276 len = sizeof(int);
3277 val = po->origdev;
3278
3279 data = &val;
3280 break;
3281 case PACKET_VNET_HDR:
3282 if (len > sizeof(int))
3283 len = sizeof(int);
3284 val = po->has_vnet_hdr;
3285
3286 data = &val;
3287 break;
3288 case PACKET_VERSION:
3289 if (len > sizeof(int))
3290 len = sizeof(int);
3291 val = po->tp_version;
3292 data = &val;
3293 break;
3294 case PACKET_HDRLEN:
3295 if (len > sizeof(int))
3296 len = sizeof(int);
3297 if (copy_from_user(&val, optval, len))
3298 return -EFAULT;
3299 switch (val) {
3300 case TPACKET_V1:
3301 val = sizeof(struct tpacket_hdr);
3302 break;
3303 case TPACKET_V2:
3304 val = sizeof(struct tpacket2_hdr);
3305 break;
3306 case TPACKET_V3:
3307 val = sizeof(struct tpacket3_hdr);
3308 break;
3309 default:
3310 return -EINVAL;
3311 }
3312 data = &val;
3313 break;
3314 case PACKET_RESERVE:
3315 if (len > sizeof(unsigned int))
3316 len = sizeof(unsigned int);
3317 val = po->tp_reserve;
3318 data = &val;
3319 break;
3320 case PACKET_LOSS:
3321 if (len > sizeof(unsigned int))
3322 len = sizeof(unsigned int);
3323 val = po->tp_loss;
3324 data = &val;
3325 break;
3326 case PACKET_TIMESTAMP:
3327 if (len > sizeof(int))
3328 len = sizeof(int);
3329 val = po->tp_tstamp;
3330 data = &val;
3331 break;
3332 case PACKET_FANOUT:
3333 if (len > sizeof(int))
3334 len = sizeof(int);
3335 val = (po->fanout ?
3336 ((u32)po->fanout->id |
3337 ((u32)po->fanout->type << 16)) :
3338 0);
3339 data = &val;
3340 break;
3341 default:
3342 return -ENOPROTOOPT;
3343 }
3344
3345 if (put_user(len, optlen))
3346 return -EFAULT;
3347 if (copy_to_user(optval, data, len))
3348 return -EFAULT;
3349 return 0;
3350 }
3351
3352
3353 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3354 {
3355 struct sock *sk;
3356 struct hlist_node *node;
3357 struct net_device *dev = data;
3358 struct net *net = dev_net(dev);
3359
3360 rcu_read_lock();
3361 sk_for_each_rcu(sk, node, &net->packet.sklist) {
3362 struct packet_sock *po = pkt_sk(sk);
3363
3364 switch (msg) {
3365 case NETDEV_UNREGISTER:
3366 if (po->mclist)
3367 packet_dev_mclist(dev, po->mclist, -1);
3368 /* fallthrough */
3369
3370 case NETDEV_DOWN:
3371 if (dev->ifindex == po->ifindex) {
3372 spin_lock(&po->bind_lock);
3373 if (po->running) {
3374 __unregister_prot_hook(sk, false);
3375 sk->sk_err = ENETDOWN;
3376 if (!sock_flag(sk, SOCK_DEAD))
3377 sk->sk_error_report(sk);
3378 }
3379 if (msg == NETDEV_UNREGISTER) {
3380 po->ifindex = -1;
3381 if (po->prot_hook.dev)
3382 dev_put(po->prot_hook.dev);
3383 po->prot_hook.dev = NULL;
3384 }
3385 spin_unlock(&po->bind_lock);
3386 }
3387 break;
3388 case NETDEV_UP:
3389 if (dev->ifindex == po->ifindex) {
3390 spin_lock(&po->bind_lock);
3391 if (po->num)
3392 register_prot_hook(sk);
3393 spin_unlock(&po->bind_lock);
3394 }
3395 break;
3396 }
3397 }
3398 rcu_read_unlock();
3399 return NOTIFY_DONE;
3400 }
3401
3402
3403 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3404 unsigned long arg)
3405 {
3406 struct sock *sk = sock->sk;
3407
3408 switch (cmd) {
3409 case SIOCOUTQ:
3410 {
3411 int amount = sk_wmem_alloc_get(sk);
3412
3413 return put_user(amount, (int __user *)arg);
3414 }
3415 case SIOCINQ:
3416 {
3417 struct sk_buff *skb;
3418 int amount = 0;
3419
3420 spin_lock_bh(&sk->sk_receive_queue.lock);
3421 skb = skb_peek(&sk->sk_receive_queue);
3422 if (skb)
3423 amount = skb->len;
3424 spin_unlock_bh(&sk->sk_receive_queue.lock);
3425 return put_user(amount, (int __user *)arg);
3426 }
3427 case SIOCGSTAMP:
3428 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3429 case SIOCGSTAMPNS:
3430 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3431
3432 #ifdef CONFIG_INET
3433 case SIOCADDRT:
3434 case SIOCDELRT:
3435 case SIOCDARP:
3436 case SIOCGARP:
3437 case SIOCSARP:
3438 case SIOCGIFADDR:
3439 case SIOCSIFADDR:
3440 case SIOCGIFBRDADDR:
3441 case SIOCSIFBRDADDR:
3442 case SIOCGIFNETMASK:
3443 case SIOCSIFNETMASK:
3444 case SIOCGIFDSTADDR:
3445 case SIOCSIFDSTADDR:
3446 case SIOCSIFFLAGS:
3447 return inet_dgram_ops.ioctl(sock, cmd, arg);
3448 #endif
3449
3450 default:
3451 return -ENOIOCTLCMD;
3452 }
3453 return 0;
3454 }
3455
3456 static unsigned int packet_poll(struct file *file, struct socket *sock,
3457 poll_table *wait)
3458 {
3459 struct sock *sk = sock->sk;
3460 struct packet_sock *po = pkt_sk(sk);
3461 unsigned int mask = datagram_poll(file, sock, wait);
3462
3463 spin_lock_bh(&sk->sk_receive_queue.lock);
3464 if (po->rx_ring.pg_vec) {
3465 if (!packet_previous_rx_frame(po, &po->rx_ring,
3466 TP_STATUS_KERNEL))
3467 mask |= POLLIN | POLLRDNORM;
3468 }
3469 spin_unlock_bh(&sk->sk_receive_queue.lock);
3470 spin_lock_bh(&sk->sk_write_queue.lock);
3471 if (po->tx_ring.pg_vec) {
3472 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3473 mask |= POLLOUT | POLLWRNORM;
3474 }
3475 spin_unlock_bh(&sk->sk_write_queue.lock);
3476 return mask;
3477 }
3478
3479
3480 /* Dirty? Well, I still did not learn better way to account
3481 * for user mmaps.
3482 */
3483
3484 static void packet_mm_open(struct vm_area_struct *vma)
3485 {
3486 struct file *file = vma->vm_file;
3487 struct socket *sock = file->private_data;
3488 struct sock *sk = sock->sk;
3489
3490 if (sk)
3491 atomic_inc(&pkt_sk(sk)->mapped);
3492 }
3493
3494 static void packet_mm_close(struct vm_area_struct *vma)
3495 {
3496 struct file *file = vma->vm_file;
3497 struct socket *sock = file->private_data;
3498 struct sock *sk = sock->sk;
3499
3500 if (sk)
3501 atomic_dec(&pkt_sk(sk)->mapped);
3502 }
3503
3504 static const struct vm_operations_struct packet_mmap_ops = {
3505 .open = packet_mm_open,
3506 .close = packet_mm_close,
3507 };
3508
3509 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3510 unsigned int len)
3511 {
3512 int i;
3513
3514 for (i = 0; i < len; i++) {
3515 if (likely(pg_vec[i].buffer)) {
3516 if (is_vmalloc_addr(pg_vec[i].buffer))
3517 vfree(pg_vec[i].buffer);
3518 else
3519 free_pages((unsigned long)pg_vec[i].buffer,
3520 order);
3521 pg_vec[i].buffer = NULL;
3522 }
3523 }
3524 kfree(pg_vec);
3525 }
3526
3527 static char *alloc_one_pg_vec_page(unsigned long order)
3528 {
3529 char *buffer = NULL;
3530 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3531 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3532
3533 buffer = (char *) __get_free_pages(gfp_flags, order);
3534
3535 if (buffer)
3536 return buffer;
3537
3538 /*
3539 * __get_free_pages failed, fall back to vmalloc
3540 */
3541 buffer = vzalloc((1 << order) * PAGE_SIZE);
3542
3543 if (buffer)
3544 return buffer;
3545
3546 /*
3547 * vmalloc failed, lets dig into swap here
3548 */
3549 gfp_flags &= ~__GFP_NORETRY;
3550 buffer = (char *)__get_free_pages(gfp_flags, order);
3551 if (buffer)
3552 return buffer;
3553
3554 /*
3555 * complete and utter failure
3556 */
3557 return NULL;
3558 }
3559
3560 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3561 {
3562 unsigned int block_nr = req->tp_block_nr;
3563 struct pgv *pg_vec;
3564 int i;
3565
3566 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3567 if (unlikely(!pg_vec))
3568 goto out;
3569
3570 for (i = 0; i < block_nr; i++) {
3571 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3572 if (unlikely(!pg_vec[i].buffer))
3573 goto out_free_pgvec;
3574 }
3575
3576 out:
3577 return pg_vec;
3578
3579 out_free_pgvec:
3580 free_pg_vec(pg_vec, order, block_nr);
3581 pg_vec = NULL;
3582 goto out;
3583 }
3584
3585 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3586 int closing, int tx_ring)
3587 {
3588 struct pgv *pg_vec = NULL;
3589 struct packet_sock *po = pkt_sk(sk);
3590 int was_running, order = 0;
3591 struct packet_ring_buffer *rb;
3592 struct sk_buff_head *rb_queue;
3593 __be16 num;
3594 int err = -EINVAL;
3595 /* Added to avoid minimal code churn */
3596 struct tpacket_req *req = &req_u->req;
3597
3598 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3599 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3600 WARN(1, "Tx-ring is not supported.\n");
3601 goto out;
3602 }
3603
3604 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3605 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3606
3607 err = -EBUSY;
3608 if (!closing) {
3609 if (atomic_read(&po->mapped))
3610 goto out;
3611 if (atomic_read(&rb->pending))
3612 goto out;
3613 }
3614
3615 if (req->tp_block_nr) {
3616 /* Sanity tests and some calculations */
3617 err = -EBUSY;
3618 if (unlikely(rb->pg_vec))
3619 goto out;
3620
3621 switch (po->tp_version) {
3622 case TPACKET_V1:
3623 po->tp_hdrlen = TPACKET_HDRLEN;
3624 break;
3625 case TPACKET_V2:
3626 po->tp_hdrlen = TPACKET2_HDRLEN;
3627 break;
3628 case TPACKET_V3:
3629 po->tp_hdrlen = TPACKET3_HDRLEN;
3630 break;
3631 }
3632
3633 err = -EINVAL;
3634 if (unlikely((int)req->tp_block_size <= 0))
3635 goto out;
3636 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3637 goto out;
3638 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3639 po->tp_reserve))
3640 goto out;
3641 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3642 goto out;
3643
3644 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3645 if (unlikely(rb->frames_per_block <= 0))
3646 goto out;
3647 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3648 req->tp_frame_nr))
3649 goto out;
3650
3651 err = -ENOMEM;
3652 order = get_order(req->tp_block_size);
3653 pg_vec = alloc_pg_vec(req, order);
3654 if (unlikely(!pg_vec))
3655 goto out;
3656 switch (po->tp_version) {
3657 case TPACKET_V3:
3658 /* Transmit path is not supported. We checked
3659 * it above but just being paranoid
3660 */
3661 if (!tx_ring)
3662 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3663 break;
3664 default:
3665 break;
3666 }
3667 }
3668 /* Done */
3669 else {
3670 err = -EINVAL;
3671 if (unlikely(req->tp_frame_nr))
3672 goto out;
3673 }
3674
3675 lock_sock(sk);
3676
3677 /* Detach socket from network */
3678 spin_lock(&po->bind_lock);
3679 was_running = po->running;
3680 num = po->num;
3681 if (was_running) {
3682 po->num = 0;
3683 __unregister_prot_hook(sk, false);
3684 }
3685 spin_unlock(&po->bind_lock);
3686
3687 synchronize_net();
3688
3689 err = -EBUSY;
3690 mutex_lock(&po->pg_vec_lock);
3691 if (closing || atomic_read(&po->mapped) == 0) {
3692 err = 0;
3693 spin_lock_bh(&rb_queue->lock);
3694 swap(rb->pg_vec, pg_vec);
3695 rb->frame_max = (req->tp_frame_nr - 1);
3696 rb->head = 0;
3697 rb->frame_size = req->tp_frame_size;
3698 spin_unlock_bh(&rb_queue->lock);
3699
3700 swap(rb->pg_vec_order, order);
3701 swap(rb->pg_vec_len, req->tp_block_nr);
3702
3703 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3704 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3705 tpacket_rcv : packet_rcv;
3706 skb_queue_purge(rb_queue);
3707 if (atomic_read(&po->mapped))
3708 pr_err("packet_mmap: vma is busy: %d\n",
3709 atomic_read(&po->mapped));
3710 }
3711 mutex_unlock(&po->pg_vec_lock);
3712
3713 spin_lock(&po->bind_lock);
3714 if (was_running) {
3715 po->num = num;
3716 register_prot_hook(sk);
3717 }
3718 spin_unlock(&po->bind_lock);
3719 if (closing && (po->tp_version > TPACKET_V2)) {
3720 /* Because we don't support block-based V3 on tx-ring */
3721 if (!tx_ring)
3722 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3723 }
3724 release_sock(sk);
3725
3726 if (pg_vec)
3727 free_pg_vec(pg_vec, order, req->tp_block_nr);
3728 out:
3729 return err;
3730 }
3731
3732 static int packet_mmap(struct file *file, struct socket *sock,
3733 struct vm_area_struct *vma)
3734 {
3735 struct sock *sk = sock->sk;
3736 struct packet_sock *po = pkt_sk(sk);
3737 unsigned long size, expected_size;
3738 struct packet_ring_buffer *rb;
3739 unsigned long start;
3740 int err = -EINVAL;
3741 int i;
3742
3743 if (vma->vm_pgoff)
3744 return -EINVAL;
3745
3746 mutex_lock(&po->pg_vec_lock);
3747
3748 expected_size = 0;
3749 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3750 if (rb->pg_vec) {
3751 expected_size += rb->pg_vec_len
3752 * rb->pg_vec_pages
3753 * PAGE_SIZE;
3754 }
3755 }
3756
3757 if (expected_size == 0)
3758 goto out;
3759
3760 size = vma->vm_end - vma->vm_start;
3761 if (size != expected_size)
3762 goto out;
3763
3764 start = vma->vm_start;
3765 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3766 if (rb->pg_vec == NULL)
3767 continue;
3768
3769 for (i = 0; i < rb->pg_vec_len; i++) {
3770 struct page *page;
3771 void *kaddr = rb->pg_vec[i].buffer;
3772 int pg_num;
3773
3774 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3775 page = pgv_to_page(kaddr);
3776 err = vm_insert_page(vma, start, page);
3777 if (unlikely(err))
3778 goto out;
3779 start += PAGE_SIZE;
3780 kaddr += PAGE_SIZE;
3781 }
3782 }
3783 }
3784
3785 atomic_inc(&po->mapped);
3786 vma->vm_ops = &packet_mmap_ops;
3787 err = 0;
3788
3789 out:
3790 mutex_unlock(&po->pg_vec_lock);
3791 return err;
3792 }
3793
3794 static const struct proto_ops packet_ops_spkt = {
3795 .family = PF_PACKET,
3796 .owner = THIS_MODULE,
3797 .release = packet_release,
3798 .bind = packet_bind_spkt,
3799 .connect = sock_no_connect,
3800 .socketpair = sock_no_socketpair,
3801 .accept = sock_no_accept,
3802 .getname = packet_getname_spkt,
3803 .poll = datagram_poll,
3804 .ioctl = packet_ioctl,
3805 .listen = sock_no_listen,
3806 .shutdown = sock_no_shutdown,
3807 .setsockopt = sock_no_setsockopt,
3808 .getsockopt = sock_no_getsockopt,
3809 .sendmsg = packet_sendmsg_spkt,
3810 .recvmsg = packet_recvmsg,
3811 .mmap = sock_no_mmap,
3812 .sendpage = sock_no_sendpage,
3813 };
3814
3815 static const struct proto_ops packet_ops = {
3816 .family = PF_PACKET,
3817 .owner = THIS_MODULE,
3818 .release = packet_release,
3819 .bind = packet_bind,
3820 .connect = sock_no_connect,
3821 .socketpair = sock_no_socketpair,
3822 .accept = sock_no_accept,
3823 .getname = packet_getname,
3824 .poll = packet_poll,
3825 .ioctl = packet_ioctl,
3826 .listen = sock_no_listen,
3827 .shutdown = sock_no_shutdown,
3828 .setsockopt = packet_setsockopt,
3829 .getsockopt = packet_getsockopt,
3830 .sendmsg = packet_sendmsg,
3831 .recvmsg = packet_recvmsg,
3832 .mmap = packet_mmap,
3833 .sendpage = sock_no_sendpage,
3834 };
3835
3836 static const struct net_proto_family packet_family_ops = {
3837 .family = PF_PACKET,
3838 .create = packet_create,
3839 .owner = THIS_MODULE,
3840 };
3841
3842 static struct notifier_block packet_netdev_notifier = {
3843 .notifier_call = packet_notifier,
3844 };
3845
3846 #ifdef CONFIG_PROC_FS
3847
3848 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3849 __acquires(RCU)
3850 {
3851 struct net *net = seq_file_net(seq);
3852
3853 rcu_read_lock();
3854 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3855 }
3856
3857 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3858 {
3859 struct net *net = seq_file_net(seq);
3860 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3861 }
3862
3863 static void packet_seq_stop(struct seq_file *seq, void *v)
3864 __releases(RCU)
3865 {
3866 rcu_read_unlock();
3867 }
3868
3869 static int packet_seq_show(struct seq_file *seq, void *v)
3870 {
3871 if (v == SEQ_START_TOKEN)
3872 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3873 else {
3874 struct sock *s = sk_entry(v);
3875 const struct packet_sock *po = pkt_sk(s);
3876
3877 seq_printf(seq,
3878 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3879 s,
3880 atomic_read(&s->sk_refcnt),
3881 s->sk_type,
3882 ntohs(po->num),
3883 po->ifindex,
3884 po->running,
3885 atomic_read(&s->sk_rmem_alloc),
3886 sock_i_uid(s),
3887 sock_i_ino(s));
3888 }
3889
3890 return 0;
3891 }
3892
3893 static const struct seq_operations packet_seq_ops = {
3894 .start = packet_seq_start,
3895 .next = packet_seq_next,
3896 .stop = packet_seq_stop,
3897 .show = packet_seq_show,
3898 };
3899
3900 static int packet_seq_open(struct inode *inode, struct file *file)
3901 {
3902 return seq_open_net(inode, file, &packet_seq_ops,
3903 sizeof(struct seq_net_private));
3904 }
3905
3906 static const struct file_operations packet_seq_fops = {
3907 .owner = THIS_MODULE,
3908 .open = packet_seq_open,
3909 .read = seq_read,
3910 .llseek = seq_lseek,
3911 .release = seq_release_net,
3912 };
3913
3914 #endif
3915
3916 static int __net_init packet_net_init(struct net *net)
3917 {
3918 spin_lock_init(&net->packet.sklist_lock);
3919 INIT_HLIST_HEAD(&net->packet.sklist);
3920
3921 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3922 return -ENOMEM;
3923
3924 return 0;
3925 }
3926
3927 static void __net_exit packet_net_exit(struct net *net)
3928 {
3929 proc_net_remove(net, "packet");
3930 }
3931
3932 static struct pernet_operations packet_net_ops = {
3933 .init = packet_net_init,
3934 .exit = packet_net_exit,
3935 };
3936
3937
3938 static void __exit packet_exit(void)
3939 {
3940 unregister_netdevice_notifier(&packet_netdev_notifier);
3941 unregister_pernet_subsys(&packet_net_ops);
3942 sock_unregister(PF_PACKET);
3943 proto_unregister(&packet_proto);
3944 }
3945
3946 static int __init packet_init(void)
3947 {
3948 int rc = proto_register(&packet_proto, 0);
3949
3950 if (rc != 0)
3951 goto out;
3952
3953 sock_register(&packet_family_ops);
3954 register_pernet_subsys(&packet_net_ops);
3955 register_netdevice_notifier(&packet_netdev_notifier);
3956 out:
3957 return rc;
3958 }
3959
3960 module_init(packet_init);
3961 module_exit(packet_exit);
3962 MODULE_LICENSE("GPL");
3963 MODULE_ALIAS_NETPROTO(PF_PACKET);
kernel source for telekom puls (alcatel/mediatek)