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net: relax rcvbuf limits
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / packet / af_packet.c
blob3891702b81df8fef757677dc779f4bddd2e31789
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/system.h>
77 #include <asm/uaccess.h>
78 #include <asm/ioctls.h>
79 #include <asm/page.h>
80 #include <asm/cacheflush.h>
81 #include <asm/io.h>
82 #include <linux/proc_fs.h>
83 #include <linux/seq_file.h>
84 #include <linux/poll.h>
85 #include <linux/module.h>
86 #include <linux/init.h>
87 #include <linux/mutex.h>
88 #include <linux/if_vlan.h>
89 #include <linux/virtio_net.h>
90 #include <linux/errqueue.h>
91 #include <linux/net_tstamp.h>
92
93 #ifdef CONFIG_INET
94 #include <net/inet_common.h>
95 #endif
96
97 /*
98 Assumptions:
99 - if device has no dev->hard_header routine, it adds and removes ll header
100 inside itself. In this case ll header is invisible outside of device,
101 but higher levels still should reserve dev->hard_header_len.
102 Some devices are enough clever to reallocate skb, when header
103 will not fit to reserved space (tunnel), another ones are silly
104 (PPP).
105 - packet socket receives packets with pulled ll header,
106 so that SOCK_RAW should push it back.
107
108 On receive:
109 -----------
110
111 Incoming, dev->hard_header!=NULL
112 mac_header -> ll header
113 data -> data
114
115 Outgoing, dev->hard_header!=NULL
116 mac_header -> ll header
117 data -> ll header
118
119 Incoming, dev->hard_header==NULL
120 mac_header -> UNKNOWN position. It is very likely, that it points to ll
121 header. PPP makes it, that is wrong, because introduce
122 assymetry between rx and tx paths.
123 data -> data
124
125 Outgoing, dev->hard_header==NULL
126 mac_header -> data. ll header is still not built!
127 data -> data
128
129 Resume
130 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
131
132
133 On transmit:
134 ------------
135
136 dev->hard_header != NULL
137 mac_header -> ll header
138 data -> ll header
139
140 dev->hard_header == NULL (ll header is added by device, we cannot control it)
141 mac_header -> data
142 data -> data
143
144 We should set nh.raw on output to correct posistion,
145 packet classifier depends on it.
146 */
147
148 /* Private packet socket structures. */
149
150 struct packet_mclist {
151 struct packet_mclist *next;
152 int ifindex;
153 int count;
154 unsigned short type;
155 unsigned short alen;
156 unsigned char addr[MAX_ADDR_LEN];
157 };
158 /* identical to struct packet_mreq except it has
159 * a longer address field.
160 */
161 struct packet_mreq_max {
162 int mr_ifindex;
163 unsigned short mr_type;
164 unsigned short mr_alen;
165 unsigned char mr_address[MAX_ADDR_LEN];
166 };
167
168 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
169 int closing, int tx_ring);
170
171
172 #define V3_ALIGNMENT (8)
173
174 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
175
176 #define BLK_PLUS_PRIV(sz_of_priv) \
177 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
178
179 /* kbdq - kernel block descriptor queue */
180 struct tpacket_kbdq_core {
181 struct pgv *pkbdq;
182 unsigned int feature_req_word;
183 unsigned int hdrlen;
184 unsigned char reset_pending_on_curr_blk;
185 unsigned char delete_blk_timer;
186 unsigned short kactive_blk_num;
187 unsigned short blk_sizeof_priv;
188
189 /* last_kactive_blk_num:
190 * trick to see if user-space has caught up
191 * in order to avoid refreshing timer when every single pkt arrives.
192 */
193 unsigned short last_kactive_blk_num;
194
195 char *pkblk_start;
196 char *pkblk_end;
197 int kblk_size;
198 unsigned int knum_blocks;
199 uint64_t knxt_seq_num;
200 char *prev;
201 char *nxt_offset;
202 struct sk_buff *skb;
203
204 atomic_t blk_fill_in_prog;
205
206 /* Default is set to 8ms */
207 #define DEFAULT_PRB_RETIRE_TOV (8)
208
209 unsigned short retire_blk_tov;
210 unsigned short version;
211 unsigned long tov_in_jiffies;
212
213 /* timer to retire an outstanding block */
214 struct timer_list retire_blk_timer;
215 };
216
217 #define PGV_FROM_VMALLOC 1
218 struct pgv {
219 char *buffer;
220 };
221
222 struct packet_ring_buffer {
223 struct pgv *pg_vec;
224 unsigned int head;
225 unsigned int frames_per_block;
226 unsigned int frame_size;
227 unsigned int frame_max;
228
229 unsigned int pg_vec_order;
230 unsigned int pg_vec_pages;
231 unsigned int pg_vec_len;
232
233 struct tpacket_kbdq_core prb_bdqc;
234 atomic_t pending;
235 };
236
237 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
238 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
239 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
240 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
241 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
242 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
243 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
244
245 struct packet_sock;
246 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
247
248 static void *packet_previous_frame(struct packet_sock *po,
249 struct packet_ring_buffer *rb,
250 int status);
251 static void packet_increment_head(struct packet_ring_buffer *buff);
252 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
253 struct tpacket_block_desc *);
254 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
255 struct packet_sock *);
256 static void prb_retire_current_block(struct tpacket_kbdq_core *,
257 struct packet_sock *, unsigned int status);
258 static int prb_queue_frozen(struct tpacket_kbdq_core *);
259 static void prb_open_block(struct tpacket_kbdq_core *,
260 struct tpacket_block_desc *);
261 static void prb_retire_rx_blk_timer_expired(unsigned long);
262 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
263 static void prb_init_blk_timer(struct packet_sock *,
264 struct tpacket_kbdq_core *,
265 void (*func) (unsigned long));
266 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
267 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
268 struct tpacket3_hdr *);
269 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
270 struct tpacket3_hdr *);
271 static void packet_flush_mclist(struct sock *sk);
272
273 struct packet_fanout;
274 struct packet_sock {
275 /* struct sock has to be the first member of packet_sock */
276 struct sock sk;
277 struct packet_fanout *fanout;
278 struct tpacket_stats stats;
279 union tpacket_stats_u stats_u;
280 struct packet_ring_buffer rx_ring;
281 struct packet_ring_buffer tx_ring;
282 int copy_thresh;
283 spinlock_t bind_lock;
284 struct mutex pg_vec_lock;
285 unsigned int running:1, /* prot_hook is attached*/
286 auxdata:1,
287 origdev:1,
288 has_vnet_hdr:1;
289 int ifindex; /* bound device */
290 __be16 num;
291 struct packet_mclist *mclist;
292 atomic_t mapped;
293 enum tpacket_versions tp_version;
294 unsigned int tp_hdrlen;
295 unsigned int tp_reserve;
296 unsigned int tp_loss:1;
297 unsigned int tp_tstamp;
298 struct packet_type prot_hook ____cacheline_aligned_in_smp;
299 };
300
301 #define PACKET_FANOUT_MAX 256
302
303 struct packet_fanout {
304 #ifdef CONFIG_NET_NS
305 struct net *net;
306 #endif
307 unsigned int num_members;
308 u16 id;
309 u8 type;
310 u8 defrag;
311 atomic_t rr_cur;
312 struct list_head list;
313 struct sock *arr[PACKET_FANOUT_MAX];
314 spinlock_t lock;
315 atomic_t sk_ref;
316 struct packet_type prot_hook ____cacheline_aligned_in_smp;
317 };
318
319 struct packet_skb_cb {
320 unsigned int origlen;
321 union {
322 struct sockaddr_pkt pkt;
323 struct sockaddr_ll ll;
324 } sa;
325 };
326
327 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
328
329 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
330 #define GET_PBLOCK_DESC(x, bid) \
331 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
332 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
333 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
334 #define GET_NEXT_PRB_BLK_NUM(x) \
335 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
336 ((x)->kactive_blk_num+1) : 0)
337
338 static struct packet_sock *pkt_sk(struct sock *sk)
339 {
340 return (struct packet_sock *)sk;
341 }
342
343 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
344 static void __fanout_link(struct sock *sk, struct packet_sock *po);
345
346 /* register_prot_hook must be invoked with the po->bind_lock held,
347 * or from a context in which asynchronous accesses to the packet
348 * socket is not possible (packet_create()).
349 */
350 static void register_prot_hook(struct sock *sk)
351 {
352 struct packet_sock *po = pkt_sk(sk);
353 if (!po->running) {
354 if (po->fanout)
355 __fanout_link(sk, po);
356 else
357 dev_add_pack(&po->prot_hook);
358 sock_hold(sk);
359 po->running = 1;
360 }
361 }
362
363 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
364 * held. If the sync parameter is true, we will temporarily drop
365 * the po->bind_lock and do a synchronize_net to make sure no
366 * asynchronous packet processing paths still refer to the elements
367 * of po->prot_hook. If the sync parameter is false, it is the
368 * callers responsibility to take care of this.
369 */
370 static void __unregister_prot_hook(struct sock *sk, bool sync)
371 {
372 struct packet_sock *po = pkt_sk(sk);
373
374 po->running = 0;
375 if (po->fanout)
376 __fanout_unlink(sk, po);
377 else
378 __dev_remove_pack(&po->prot_hook);
379 __sock_put(sk);
380
381 if (sync) {
382 spin_unlock(&po->bind_lock);
383 synchronize_net();
384 spin_lock(&po->bind_lock);
385 }
386 }
387
388 static void unregister_prot_hook(struct sock *sk, bool sync)
389 {
390 struct packet_sock *po = pkt_sk(sk);
391
392 if (po->running)
393 __unregister_prot_hook(sk, sync);
394 }
395
396 static inline __pure struct page *pgv_to_page(void *addr)
397 {
398 if (is_vmalloc_addr(addr))
399 return vmalloc_to_page(addr);
400 return virt_to_page(addr);
401 }
402
403 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
404 {
405 union {
406 struct tpacket_hdr *h1;
407 struct tpacket2_hdr *h2;
408 void *raw;
409 } h;
410
411 h.raw = frame;
412 switch (po->tp_version) {
413 case TPACKET_V1:
414 h.h1->tp_status = status;
415 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
416 break;
417 case TPACKET_V2:
418 h.h2->tp_status = status;
419 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
420 break;
421 case TPACKET_V3:
422 default:
423 WARN(1, "TPACKET version not supported.\n");
424 BUG();
425 }
426
427 smp_wmb();
428 }
429
430 static int __packet_get_status(struct packet_sock *po, void *frame)
431 {
432 union {
433 struct tpacket_hdr *h1;
434 struct tpacket2_hdr *h2;
435 void *raw;
436 } h;
437
438 smp_rmb();
439
440 h.raw = frame;
441 switch (po->tp_version) {
442 case TPACKET_V1:
443 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
444 return h.h1->tp_status;
445 case TPACKET_V2:
446 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
447 return h.h2->tp_status;
448 case TPACKET_V3:
449 default:
450 WARN(1, "TPACKET version not supported.\n");
451 BUG();
452 return 0;
453 }
454 }
455
456 static void *packet_lookup_frame(struct packet_sock *po,
457 struct packet_ring_buffer *rb,
458 unsigned int position,
459 int status)
460 {
461 unsigned int pg_vec_pos, frame_offset;
462 union {
463 struct tpacket_hdr *h1;
464 struct tpacket2_hdr *h2;
465 void *raw;
466 } h;
467
468 pg_vec_pos = position / rb->frames_per_block;
469 frame_offset = position % rb->frames_per_block;
470
471 h.raw = rb->pg_vec[pg_vec_pos].buffer +
472 (frame_offset * rb->frame_size);
473
474 if (status != __packet_get_status(po, h.raw))
475 return NULL;
476
477 return h.raw;
478 }
479
480 static void *packet_current_frame(struct packet_sock *po,
481 struct packet_ring_buffer *rb,
482 int status)
483 {
484 return packet_lookup_frame(po, rb, rb->head, status);
485 }
486
487 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
488 {
489 del_timer_sync(&pkc->retire_blk_timer);
490 }
491
492 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
493 int tx_ring,
494 struct sk_buff_head *rb_queue)
495 {
496 struct tpacket_kbdq_core *pkc;
497
498 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
499
500 spin_lock(&rb_queue->lock);
501 pkc->delete_blk_timer = 1;
502 spin_unlock(&rb_queue->lock);
503
504 prb_del_retire_blk_timer(pkc);
505 }
506
507 static void prb_init_blk_timer(struct packet_sock *po,
508 struct tpacket_kbdq_core *pkc,
509 void (*func) (unsigned long))
510 {
511 init_timer(&pkc->retire_blk_timer);
512 pkc->retire_blk_timer.data = (long)po;
513 pkc->retire_blk_timer.function = func;
514 pkc->retire_blk_timer.expires = jiffies;
515 }
516
517 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
518 {
519 struct tpacket_kbdq_core *pkc;
520
521 if (tx_ring)
522 BUG();
523
524 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
525 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
526 }
527
528 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
529 int blk_size_in_bytes)
530 {
531 struct net_device *dev;
532 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
533 struct ethtool_cmd ecmd;
534 int err;
535
536 rtnl_lock();
537 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
538 if (unlikely(!dev)) {
539 rtnl_unlock();
540 return DEFAULT_PRB_RETIRE_TOV;
541 }
542 err = __ethtool_get_settings(dev, &ecmd);
543 rtnl_unlock();
544 if (!err) {
545 switch (ecmd.speed) {
546 case SPEED_10000:
547 msec = 1;
548 div = 10000/1000;
549 break;
550 case SPEED_1000:
551 msec = 1;
552 div = 1000/1000;
553 break;
554 /*
555 * If the link speed is so slow you don't really
556 * need to worry about perf anyways
557 */
558 case SPEED_100:
559 case SPEED_10:
560 default:
561 return DEFAULT_PRB_RETIRE_TOV;
562 }
563 }
564
565 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
566
567 if (div)
568 mbits /= div;
569
570 tmo = mbits * msec;
571
572 if (div)
573 return tmo+1;
574 return tmo;
575 }
576
577 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
578 union tpacket_req_u *req_u)
579 {
580 p1->feature_req_word = req_u->req3.tp_feature_req_word;
581 }
582
583 static void init_prb_bdqc(struct packet_sock *po,
584 struct packet_ring_buffer *rb,
585 struct pgv *pg_vec,
586 union tpacket_req_u *req_u, int tx_ring)
587 {
588 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
589 struct tpacket_block_desc *pbd;
590
591 memset(p1, 0x0, sizeof(*p1));
592
593 p1->knxt_seq_num = 1;
594 p1->pkbdq = pg_vec;
595 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
596 p1->pkblk_start = (char *)pg_vec[0].buffer;
597 p1->kblk_size = req_u->req3.tp_block_size;
598 p1->knum_blocks = req_u->req3.tp_block_nr;
599 p1->hdrlen = po->tp_hdrlen;
600 p1->version = po->tp_version;
601 p1->last_kactive_blk_num = 0;
602 po->stats_u.stats3.tp_freeze_q_cnt = 0;
603 if (req_u->req3.tp_retire_blk_tov)
604 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
605 else
606 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
607 req_u->req3.tp_block_size);
608 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
609 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
610
611 prb_init_ft_ops(p1, req_u);
612 prb_setup_retire_blk_timer(po, tx_ring);
613 prb_open_block(p1, pbd);
614 }
615
616 /* Do NOT update the last_blk_num first.
617 * Assumes sk_buff_head lock is held.
618 */
619 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
620 {
621 mod_timer(&pkc->retire_blk_timer,
622 jiffies + pkc->tov_in_jiffies);
623 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
624 }
625
626 /*
627 * Timer logic:
628 * 1) We refresh the timer only when we open a block.
629 * By doing this we don't waste cycles refreshing the timer
630 * on packet-by-packet basis.
631 *
632 * With a 1MB block-size, on a 1Gbps line, it will take
633 * i) ~8 ms to fill a block + ii) memcpy etc.
634 * In this cut we are not accounting for the memcpy time.
635 *
636 * So, if the user sets the 'tmo' to 10ms then the timer
637 * will never fire while the block is still getting filled
638 * (which is what we want). However, the user could choose
639 * to close a block early and that's fine.
640 *
641 * But when the timer does fire, we check whether or not to refresh it.
642 * Since the tmo granularity is in msecs, it is not too expensive
643 * to refresh the timer, lets say every '8' msecs.
644 * Either the user can set the 'tmo' or we can derive it based on
645 * a) line-speed and b) block-size.
646 * prb_calc_retire_blk_tmo() calculates the tmo.
647 *
648 */
649 static void prb_retire_rx_blk_timer_expired(unsigned long data)
650 {
651 struct packet_sock *po = (struct packet_sock *)data;
652 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
653 unsigned int frozen;
654 struct tpacket_block_desc *pbd;
655
656 spin_lock(&po->sk.sk_receive_queue.lock);
657
658 frozen = prb_queue_frozen(pkc);
659 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
660
661 if (unlikely(pkc->delete_blk_timer))
662 goto out;
663
664 /* We only need to plug the race when the block is partially filled.
665 * tpacket_rcv:
666 * lock(); increment BLOCK_NUM_PKTS; unlock()
667 * copy_bits() is in progress ...
668 * timer fires on other cpu:
669 * we can't retire the current block because copy_bits
670 * is in progress.
671 *
672 */
673 if (BLOCK_NUM_PKTS(pbd)) {
674 while (atomic_read(&pkc->blk_fill_in_prog)) {
675 /* Waiting for skb_copy_bits to finish... */
676 cpu_relax();
677 }
678 }
679
680 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
681 if (!frozen) {
682 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
683 if (!prb_dispatch_next_block(pkc, po))
684 goto refresh_timer;
685 else
686 goto out;
687 } else {
688 /* Case 1. Queue was frozen because user-space was
689 * lagging behind.
690 */
691 if (prb_curr_blk_in_use(pkc, pbd)) {
692 /*
693 * Ok, user-space is still behind.
694 * So just refresh the timer.
695 */
696 goto refresh_timer;
697 } else {
698 /* Case 2. queue was frozen,user-space caught up,
699 * now the link went idle && the timer fired.
700 * We don't have a block to close.So we open this
701 * block and restart the timer.
702 * opening a block thaws the queue,restarts timer
703 * Thawing/timer-refresh is a side effect.
704 */
705 prb_open_block(pkc, pbd);
706 goto out;
707 }
708 }
709 }
710
711 refresh_timer:
712 _prb_refresh_rx_retire_blk_timer(pkc);
713
714 out:
715 spin_unlock(&po->sk.sk_receive_queue.lock);
716 }
717
718 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
719 struct tpacket_block_desc *pbd1, __u32 status)
720 {
721 /* Flush everything minus the block header */
722
723 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
724 u8 *start, *end;
725
726 start = (u8 *)pbd1;
727
728 /* Skip the block header(we know header WILL fit in 4K) */
729 start += PAGE_SIZE;
730
731 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
732 for (; start < end; start += PAGE_SIZE)
733 flush_dcache_page(pgv_to_page(start));
734
735 smp_wmb();
736 #endif
737
738 /* Now update the block status. */
739
740 BLOCK_STATUS(pbd1) = status;
741
742 /* Flush the block header */
743
744 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
745 start = (u8 *)pbd1;
746 flush_dcache_page(pgv_to_page(start));
747
748 smp_wmb();
749 #endif
750 }
751
752 /*
753 * Side effect:
754 *
755 * 1) flush the block
756 * 2) Increment active_blk_num
757 *
758 * Note:We DONT refresh the timer on purpose.
759 * Because almost always the next block will be opened.
760 */
761 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
762 struct tpacket_block_desc *pbd1,
763 struct packet_sock *po, unsigned int stat)
764 {
765 __u32 status = TP_STATUS_USER | stat;
766
767 struct tpacket3_hdr *last_pkt;
768 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
769
770 if (po->stats.tp_drops)
771 status |= TP_STATUS_LOSING;
772
773 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
774 last_pkt->tp_next_offset = 0;
775
776 /* Get the ts of the last pkt */
777 if (BLOCK_NUM_PKTS(pbd1)) {
778 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
779 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
780 } else {
781 /* Ok, we tmo'd - so get the current time */
782 struct timespec ts;
783 getnstimeofday(&ts);
784 h1->ts_last_pkt.ts_sec = ts.tv_sec;
785 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
786 }
787
788 smp_wmb();
789
790 /* Flush the block */
791 prb_flush_block(pkc1, pbd1, status);
792
793 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
794 }
795
796 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
797 {
798 pkc->reset_pending_on_curr_blk = 0;
799 }
800
801 /*
802 * Side effect of opening a block:
803 *
804 * 1) prb_queue is thawed.
805 * 2) retire_blk_timer is refreshed.
806 *
807 */
808 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
809 struct tpacket_block_desc *pbd1)
810 {
811 struct timespec ts;
812 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
813
814 smp_rmb();
815
816 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd1))) {
817
818 /* We could have just memset this but we will lose the
819 * flexibility of making the priv area sticky
820 */
821 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
822 BLOCK_NUM_PKTS(pbd1) = 0;
823 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
824 getnstimeofday(&ts);
825 h1->ts_first_pkt.ts_sec = ts.tv_sec;
826 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
827 pkc1->pkblk_start = (char *)pbd1;
828 pkc1->nxt_offset = (char *)(pkc1->pkblk_start +
829 BLK_PLUS_PRIV(pkc1->blk_sizeof_priv));
830 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
831 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
832 pbd1->version = pkc1->version;
833 pkc1->prev = pkc1->nxt_offset;
834 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
835 prb_thaw_queue(pkc1);
836 _prb_refresh_rx_retire_blk_timer(pkc1);
837
838 smp_wmb();
839
840 return;
841 }
842
843 WARN(1, "ERROR block:%p is NOT FREE status:%d kactive_blk_num:%d\n",
844 pbd1, BLOCK_STATUS(pbd1), pkc1->kactive_blk_num);
845 dump_stack();
846 BUG();
847 }
848
849 /*
850 * Queue freeze logic:
851 * 1) Assume tp_block_nr = 8 blocks.
852 * 2) At time 't0', user opens Rx ring.
853 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
854 * 4) user-space is either sleeping or processing block '0'.
855 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
856 * it will close block-7,loop around and try to fill block '0'.
857 * call-flow:
858 * __packet_lookup_frame_in_block
859 * prb_retire_current_block()
860 * prb_dispatch_next_block()
861 * |->(BLOCK_STATUS == USER) evaluates to true
862 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
863 * 6) Now there are two cases:
864 * 6.1) Link goes idle right after the queue is frozen.
865 * But remember, the last open_block() refreshed the timer.
866 * When this timer expires,it will refresh itself so that we can
867 * re-open block-0 in near future.
868 * 6.2) Link is busy and keeps on receiving packets. This is a simple
869 * case and __packet_lookup_frame_in_block will check if block-0
870 * is free and can now be re-used.
871 */
872 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
873 struct packet_sock *po)
874 {
875 pkc->reset_pending_on_curr_blk = 1;
876 po->stats_u.stats3.tp_freeze_q_cnt++;
877 }
878
879 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
880
881 /*
882 * If the next block is free then we will dispatch it
883 * and return a good offset.
884 * Else, we will freeze the queue.
885 * So, caller must check the return value.
886 */
887 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
888 struct packet_sock *po)
889 {
890 struct tpacket_block_desc *pbd;
891
892 smp_rmb();
893
894 /* 1. Get current block num */
895 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
896
897 /* 2. If this block is currently in_use then freeze the queue */
898 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
899 prb_freeze_queue(pkc, po);
900 return NULL;
901 }
902
903 /*
904 * 3.
905 * open this block and return the offset where the first packet
906 * needs to get stored.
907 */
908 prb_open_block(pkc, pbd);
909 return (void *)pkc->nxt_offset;
910 }
911
912 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
913 struct packet_sock *po, unsigned int status)
914 {
915 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
916
917 /* retire/close the current block */
918 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
919 /*
920 * Plug the case where copy_bits() is in progress on
921 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
922 * have space to copy the pkt in the current block and
923 * called prb_retire_current_block()
924 *
925 * We don't need to worry about the TMO case because
926 * the timer-handler already handled this case.
927 */
928 if (!(status & TP_STATUS_BLK_TMO)) {
929 while (atomic_read(&pkc->blk_fill_in_prog)) {
930 /* Waiting for skb_copy_bits to finish... */
931 cpu_relax();
932 }
933 }
934 prb_close_block(pkc, pbd, po, status);
935 return;
936 }
937
938 WARN(1, "ERROR-pbd[%d]:%p\n", pkc->kactive_blk_num, pbd);
939 dump_stack();
940 BUG();
941 }
942
943 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
944 struct tpacket_block_desc *pbd)
945 {
946 return TP_STATUS_USER & BLOCK_STATUS(pbd);
947 }
948
949 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
950 {
951 return pkc->reset_pending_on_curr_blk;
952 }
953
954 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
955 {
956 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
957 atomic_dec(&pkc->blk_fill_in_prog);
958 }
959
960 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
961 struct tpacket3_hdr *ppd)
962 {
963 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
964 }
965
966 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
967 struct tpacket3_hdr *ppd)
968 {
969 ppd->hv1.tp_rxhash = 0;
970 }
971
972 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
973 struct tpacket3_hdr *ppd)
974 {
975 if (vlan_tx_tag_present(pkc->skb)) {
976 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
977 ppd->tp_status = TP_STATUS_VLAN_VALID;
978 } else {
979 ppd->hv1.tp_vlan_tci = ppd->tp_status = 0;
980 }
981 }
982
983 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
984 struct tpacket3_hdr *ppd)
985 {
986 prb_fill_vlan_info(pkc, ppd);
987
988 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
989 prb_fill_rxhash(pkc, ppd);
990 else
991 prb_clear_rxhash(pkc, ppd);
992 }
993
994 static void prb_fill_curr_block(char *curr,
995 struct tpacket_kbdq_core *pkc,
996 struct tpacket_block_desc *pbd,
997 unsigned int len)
998 {
999 struct tpacket3_hdr *ppd;
1000
1001 ppd = (struct tpacket3_hdr *)curr;
1002 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1003 pkc->prev = curr;
1004 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1005 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1006 BLOCK_NUM_PKTS(pbd) += 1;
1007 atomic_inc(&pkc->blk_fill_in_prog);
1008 prb_run_all_ft_ops(pkc, ppd);
1009 }
1010
1011 /* Assumes caller has the sk->rx_queue.lock */
1012 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1013 struct sk_buff *skb,
1014 int status,
1015 unsigned int len
1016 )
1017 {
1018 struct tpacket_kbdq_core *pkc;
1019 struct tpacket_block_desc *pbd;
1020 char *curr, *end;
1021
1022 pkc = GET_PBDQC_FROM_RB(((struct packet_ring_buffer *)&po->rx_ring));
1023 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1024
1025 /* Queue is frozen when user space is lagging behind */
1026 if (prb_queue_frozen(pkc)) {
1027 /*
1028 * Check if that last block which caused the queue to freeze,
1029 * is still in_use by user-space.
1030 */
1031 if (prb_curr_blk_in_use(pkc, pbd)) {
1032 /* Can't record this packet */
1033 return NULL;
1034 } else {
1035 /*
1036 * Ok, the block was released by user-space.
1037 * Now let's open that block.
1038 * opening a block also thaws the queue.
1039 * Thawing is a side effect.
1040 */
1041 prb_open_block(pkc, pbd);
1042 }
1043 }
1044
1045 smp_mb();
1046 curr = pkc->nxt_offset;
1047 pkc->skb = skb;
1048 end = (char *) ((char *)pbd + pkc->kblk_size);
1049
1050 /* first try the current block */
1051 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1052 prb_fill_curr_block(curr, pkc, pbd, len);
1053 return (void *)curr;
1054 }
1055
1056 /* Ok, close the current block */
1057 prb_retire_current_block(pkc, po, 0);
1058
1059 /* Now, try to dispatch the next block */
1060 curr = (char *)prb_dispatch_next_block(pkc, po);
1061 if (curr) {
1062 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1063 prb_fill_curr_block(curr, pkc, pbd, len);
1064 return (void *)curr;
1065 }
1066
1067 /*
1068 * No free blocks are available.user_space hasn't caught up yet.
1069 * Queue was just frozen and now this packet will get dropped.
1070 */
1071 return NULL;
1072 }
1073
1074 static void *packet_current_rx_frame(struct packet_sock *po,
1075 struct sk_buff *skb,
1076 int status, unsigned int len)
1077 {
1078 char *curr = NULL;
1079 switch (po->tp_version) {
1080 case TPACKET_V1:
1081 case TPACKET_V2:
1082 curr = packet_lookup_frame(po, &po->rx_ring,
1083 po->rx_ring.head, status);
1084 return curr;
1085 case TPACKET_V3:
1086 return __packet_lookup_frame_in_block(po, skb, status, len);
1087 default:
1088 WARN(1, "TPACKET version not supported\n");
1089 BUG();
1090 return 0;
1091 }
1092 }
1093
1094 static void *prb_lookup_block(struct packet_sock *po,
1095 struct packet_ring_buffer *rb,
1096 unsigned int previous,
1097 int status)
1098 {
1099 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1100 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, previous);
1101
1102 if (status != BLOCK_STATUS(pbd))
1103 return NULL;
1104 return pbd;
1105 }
1106
1107 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1108 {
1109 unsigned int prev;
1110 if (rb->prb_bdqc.kactive_blk_num)
1111 prev = rb->prb_bdqc.kactive_blk_num-1;
1112 else
1113 prev = rb->prb_bdqc.knum_blocks-1;
1114 return prev;
1115 }
1116
1117 /* Assumes caller has held the rx_queue.lock */
1118 static void *__prb_previous_block(struct packet_sock *po,
1119 struct packet_ring_buffer *rb,
1120 int status)
1121 {
1122 unsigned int previous = prb_previous_blk_num(rb);
1123 return prb_lookup_block(po, rb, previous, status);
1124 }
1125
1126 static void *packet_previous_rx_frame(struct packet_sock *po,
1127 struct packet_ring_buffer *rb,
1128 int status)
1129 {
1130 if (po->tp_version <= TPACKET_V2)
1131 return packet_previous_frame(po, rb, status);
1132
1133 return __prb_previous_block(po, rb, status);
1134 }
1135
1136 static void packet_increment_rx_head(struct packet_sock *po,
1137 struct packet_ring_buffer *rb)
1138 {
1139 switch (po->tp_version) {
1140 case TPACKET_V1:
1141 case TPACKET_V2:
1142 return packet_increment_head(rb);
1143 case TPACKET_V3:
1144 default:
1145 WARN(1, "TPACKET version not supported.\n");
1146 BUG();
1147 return;
1148 }
1149 }
1150
1151 static void *packet_previous_frame(struct packet_sock *po,
1152 struct packet_ring_buffer *rb,
1153 int status)
1154 {
1155 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1156 return packet_lookup_frame(po, rb, previous, status);
1157 }
1158
1159 static void packet_increment_head(struct packet_ring_buffer *buff)
1160 {
1161 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1162 }
1163
1164 static void packet_sock_destruct(struct sock *sk)
1165 {
1166 skb_queue_purge(&sk->sk_error_queue);
1167
1168 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1169 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1170
1171 if (!sock_flag(sk, SOCK_DEAD)) {
1172 pr_err("Attempt to release alive packet socket: %p\n", sk);
1173 return;
1174 }
1175
1176 sk_refcnt_debug_dec(sk);
1177 }
1178
1179 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1180 {
1181 int x = atomic_read(&f->rr_cur) + 1;
1182
1183 if (x >= num)
1184 x = 0;
1185
1186 return x;
1187 }
1188
1189 static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1190 {
1191 u32 idx, hash = skb->rxhash;
1192
1193 idx = ((u64)hash * num) >> 32;
1194
1195 return f->arr[idx];
1196 }
1197
1198 static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1199 {
1200 int cur, old;
1201
1202 cur = atomic_read(&f->rr_cur);
1203 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1204 fanout_rr_next(f, num))) != cur)
1205 cur = old;
1206 return f->arr[cur];
1207 }
1208
1209 static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1210 {
1211 unsigned int cpu = smp_processor_id();
1212
1213 return f->arr[cpu % num];
1214 }
1215
1216 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1217 struct packet_type *pt, struct net_device *orig_dev)
1218 {
1219 struct packet_fanout *f = pt->af_packet_priv;
1220 unsigned int num = f->num_members;
1221 struct packet_sock *po;
1222 struct sock *sk;
1223
1224 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1225 !num) {
1226 kfree_skb(skb);
1227 return 0;
1228 }
1229
1230 switch (f->type) {
1231 case PACKET_FANOUT_HASH:
1232 default:
1233 if (f->defrag) {
1234 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1235 if (!skb)
1236 return 0;
1237 }
1238 skb_get_rxhash(skb);
1239 sk = fanout_demux_hash(f, skb, num);
1240 break;
1241 case PACKET_FANOUT_LB:
1242 sk = fanout_demux_lb(f, skb, num);
1243 break;
1244 case PACKET_FANOUT_CPU:
1245 sk = fanout_demux_cpu(f, skb, num);
1246 break;
1247 }
1248
1249 po = pkt_sk(sk);
1250
1251 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1252 }
1253
1254 static DEFINE_MUTEX(fanout_mutex);
1255 static LIST_HEAD(fanout_list);
1256
1257 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1258 {
1259 struct packet_fanout *f = po->fanout;
1260
1261 spin_lock(&f->lock);
1262 f->arr[f->num_members] = sk;
1263 smp_wmb();
1264 f->num_members++;
1265 spin_unlock(&f->lock);
1266 }
1267
1268 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1269 {
1270 struct packet_fanout *f = po->fanout;
1271 int i;
1272
1273 spin_lock(&f->lock);
1274 for (i = 0; i < f->num_members; i++) {
1275 if (f->arr[i] == sk)
1276 break;
1277 }
1278 BUG_ON(i >= f->num_members);
1279 f->arr[i] = f->arr[f->num_members - 1];
1280 f->num_members--;
1281 spin_unlock(&f->lock);
1282 }
1283
1284 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1285 {
1286 struct packet_sock *po = pkt_sk(sk);
1287 struct packet_fanout *f, *match;
1288 u8 type = type_flags & 0xff;
1289 u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
1290 int err;
1291
1292 switch (type) {
1293 case PACKET_FANOUT_HASH:
1294 case PACKET_FANOUT_LB:
1295 case PACKET_FANOUT_CPU:
1296 break;
1297 default:
1298 return -EINVAL;
1299 }
1300
1301 if (!po->running)
1302 return -EINVAL;
1303
1304 if (po->fanout)
1305 return -EALREADY;
1306
1307 mutex_lock(&fanout_mutex);
1308 match = NULL;
1309 list_for_each_entry(f, &fanout_list, list) {
1310 if (f->id == id &&
1311 read_pnet(&f->net) == sock_net(sk)) {
1312 match = f;
1313 break;
1314 }
1315 }
1316 err = -EINVAL;
1317 if (match && match->defrag != defrag)
1318 goto out;
1319 if (!match) {
1320 err = -ENOMEM;
1321 match = kzalloc(sizeof(*match), GFP_KERNEL);
1322 if (!match)
1323 goto out;
1324 write_pnet(&match->net, sock_net(sk));
1325 match->id = id;
1326 match->type = type;
1327 match->defrag = defrag;
1328 atomic_set(&match->rr_cur, 0);
1329 INIT_LIST_HEAD(&match->list);
1330 spin_lock_init(&match->lock);
1331 atomic_set(&match->sk_ref, 0);
1332 match->prot_hook.type = po->prot_hook.type;
1333 match->prot_hook.dev = po->prot_hook.dev;
1334 match->prot_hook.func = packet_rcv_fanout;
1335 match->prot_hook.af_packet_priv = match;
1336 dev_add_pack(&match->prot_hook);
1337 list_add(&match->list, &fanout_list);
1338 }
1339 err = -EINVAL;
1340 if (match->type == type &&
1341 match->prot_hook.type == po->prot_hook.type &&
1342 match->prot_hook.dev == po->prot_hook.dev) {
1343 err = -ENOSPC;
1344 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1345 __dev_remove_pack(&po->prot_hook);
1346 po->fanout = match;
1347 atomic_inc(&match->sk_ref);
1348 __fanout_link(sk, po);
1349 err = 0;
1350 }
1351 }
1352 out:
1353 mutex_unlock(&fanout_mutex);
1354 return err;
1355 }
1356
1357 static void fanout_release(struct sock *sk)
1358 {
1359 struct packet_sock *po = pkt_sk(sk);
1360 struct packet_fanout *f;
1361
1362 f = po->fanout;
1363 if (!f)
1364 return;
1365
1366 po->fanout = NULL;
1367
1368 mutex_lock(&fanout_mutex);
1369 if (atomic_dec_and_test(&f->sk_ref)) {
1370 list_del(&f->list);
1371 dev_remove_pack(&f->prot_hook);
1372 kfree(f);
1373 }
1374 mutex_unlock(&fanout_mutex);
1375 }
1376
1377 static const struct proto_ops packet_ops;
1378
1379 static const struct proto_ops packet_ops_spkt;
1380
1381 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1382 struct packet_type *pt, struct net_device *orig_dev)
1383 {
1384 struct sock *sk;
1385 struct sockaddr_pkt *spkt;
1386
1387 /*
1388 * When we registered the protocol we saved the socket in the data
1389 * field for just this event.
1390 */
1391
1392 sk = pt->af_packet_priv;
1393
1394 /*
1395 * Yank back the headers [hope the device set this
1396 * right or kerboom...]
1397 *
1398 * Incoming packets have ll header pulled,
1399 * push it back.
1400 *
1401 * For outgoing ones skb->data == skb_mac_header(skb)
1402 * so that this procedure is noop.
1403 */
1404
1405 if (skb->pkt_type == PACKET_LOOPBACK)
1406 goto out;
1407
1408 if (!net_eq(dev_net(dev), sock_net(sk)))
1409 goto out;
1410
1411 skb = skb_share_check(skb, GFP_ATOMIC);
1412 if (skb == NULL)
1413 goto oom;
1414
1415 /* drop any routing info */
1416 skb_dst_drop(skb);
1417
1418 /* drop conntrack reference */
1419 nf_reset(skb);
1420
1421 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1422
1423 skb_push(skb, skb->data - skb_mac_header(skb));
1424
1425 /*
1426 * The SOCK_PACKET socket receives _all_ frames.
1427 */
1428
1429 spkt->spkt_family = dev->type;
1430 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1431 spkt->spkt_protocol = skb->protocol;
1432
1433 /*
1434 * Charge the memory to the socket. This is done specifically
1435 * to prevent sockets using all the memory up.
1436 */
1437
1438 if (sock_queue_rcv_skb(sk, skb) == 0)
1439 return 0;
1440
1441 out:
1442 kfree_skb(skb);
1443 oom:
1444 return 0;
1445 }
1446
1447
1448 /*
1449 * Output a raw packet to a device layer. This bypasses all the other
1450 * protocol layers and you must therefore supply it with a complete frame
1451 */
1452
1453 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1454 struct msghdr *msg, size_t len)
1455 {
1456 struct sock *sk = sock->sk;
1457 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1458 struct sk_buff *skb = NULL;
1459 struct net_device *dev;
1460 __be16 proto = 0;
1461 int err;
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 err = -EMSGSIZE;
1497 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
1498 goto out_unlock;
1499
1500 if (!skb) {
1501 size_t reserved = LL_RESERVED_SPACE(dev);
1502 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1503
1504 rcu_read_unlock();
1505 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
1506 if (skb == NULL)
1507 return -ENOBUFS;
1508 /* FIXME: Save some space for broken drivers that write a hard
1509 * header at transmission time by themselves. PPP is the notable
1510 * one here. This should really be fixed at the driver level.
1511 */
1512 skb_reserve(skb, reserved);
1513 skb_reset_network_header(skb);
1514
1515 /* Try to align data part correctly */
1516 if (hhlen) {
1517 skb->data -= hhlen;
1518 skb->tail -= hhlen;
1519 if (len < hhlen)
1520 skb_reset_network_header(skb);
1521 }
1522 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1523 if (err)
1524 goto out_free;
1525 goto retry;
1526 }
1527
1528 if (len > (dev->mtu + dev->hard_header_len)) {
1529 /* Earlier code assumed this would be a VLAN pkt,
1530 * double-check this now that we have the actual
1531 * packet in hand.
1532 */
1533 struct ethhdr *ehdr;
1534 skb_reset_mac_header(skb);
1535 ehdr = eth_hdr(skb);
1536 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1537 err = -EMSGSIZE;
1538 goto out_unlock;
1539 }
1540 }
1541
1542 skb->protocol = proto;
1543 skb->dev = dev;
1544 skb->priority = sk->sk_priority;
1545 skb->mark = sk->sk_mark;
1546 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1547 if (err < 0)
1548 goto out_unlock;
1549
1550 dev_queue_xmit(skb);
1551 rcu_read_unlock();
1552 return len;
1553
1554 out_unlock:
1555 rcu_read_unlock();
1556 out_free:
1557 kfree_skb(skb);
1558 return err;
1559 }
1560
1561 static unsigned int run_filter(const struct sk_buff *skb,
1562 const struct sock *sk,
1563 unsigned int res)
1564 {
1565 struct sk_filter *filter;
1566
1567 rcu_read_lock();
1568 filter = rcu_dereference(sk->sk_filter);
1569 if (filter != NULL)
1570 res = SK_RUN_FILTER(filter, skb);
1571 rcu_read_unlock();
1572
1573 return res;
1574 }
1575
1576 /*
1577 * This function makes lazy skb cloning in hope that most of packets
1578 * are discarded by BPF.
1579 *
1580 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1581 * and skb->cb are mangled. It works because (and until) packets
1582 * falling here are owned by current CPU. Output packets are cloned
1583 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1584 * sequencially, so that if we return skb to original state on exit,
1585 * we will not harm anyone.
1586 */
1587
1588 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1589 struct packet_type *pt, struct net_device *orig_dev)
1590 {
1591 struct sock *sk;
1592 struct sockaddr_ll *sll;
1593 struct packet_sock *po;
1594 u8 *skb_head = skb->data;
1595 int skb_len = skb->len;
1596 unsigned int snaplen, res;
1597
1598 if (skb->pkt_type == PACKET_LOOPBACK)
1599 goto drop;
1600
1601 sk = pt->af_packet_priv;
1602 po = pkt_sk(sk);
1603
1604 if (!net_eq(dev_net(dev), sock_net(sk)))
1605 goto drop;
1606
1607 skb->dev = dev;
1608
1609 if (dev->header_ops) {
1610 /* The device has an explicit notion of ll header,
1611 * exported to higher levels.
1612 *
1613 * Otherwise, the device hides details of its frame
1614 * structure, so that corresponding packet head is
1615 * never delivered to user.
1616 */
1617 if (sk->sk_type != SOCK_DGRAM)
1618 skb_push(skb, skb->data - skb_mac_header(skb));
1619 else if (skb->pkt_type == PACKET_OUTGOING) {
1620 /* Special case: outgoing packets have ll header at head */
1621 skb_pull(skb, skb_network_offset(skb));
1622 }
1623 }
1624
1625 snaplen = skb->len;
1626
1627 res = run_filter(skb, sk, snaplen);
1628 if (!res)
1629 goto drop_n_restore;
1630 if (snaplen > res)
1631 snaplen = res;
1632
1633 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1634 goto drop_n_acct;
1635
1636 if (skb_shared(skb)) {
1637 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1638 if (nskb == NULL)
1639 goto drop_n_acct;
1640
1641 if (skb_head != skb->data) {
1642 skb->data = skb_head;
1643 skb->len = skb_len;
1644 }
1645 kfree_skb(skb);
1646 skb = nskb;
1647 }
1648
1649 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1650 sizeof(skb->cb));
1651
1652 sll = &PACKET_SKB_CB(skb)->sa.ll;
1653 sll->sll_family = AF_PACKET;
1654 sll->sll_hatype = dev->type;
1655 sll->sll_protocol = skb->protocol;
1656 sll->sll_pkttype = skb->pkt_type;
1657 if (unlikely(po->origdev))
1658 sll->sll_ifindex = orig_dev->ifindex;
1659 else
1660 sll->sll_ifindex = dev->ifindex;
1661
1662 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1663
1664 PACKET_SKB_CB(skb)->origlen = skb->len;
1665
1666 if (pskb_trim(skb, snaplen))
1667 goto drop_n_acct;
1668
1669 skb_set_owner_r(skb, sk);
1670 skb->dev = NULL;
1671 skb_dst_drop(skb);
1672
1673 /* drop conntrack reference */
1674 nf_reset(skb);
1675
1676 spin_lock(&sk->sk_receive_queue.lock);
1677 po->stats.tp_packets++;
1678 skb->dropcount = atomic_read(&sk->sk_drops);
1679 __skb_queue_tail(&sk->sk_receive_queue, skb);
1680 spin_unlock(&sk->sk_receive_queue.lock);
1681 sk->sk_data_ready(sk, skb->len);
1682 return 0;
1683
1684 drop_n_acct:
1685 spin_lock(&sk->sk_receive_queue.lock);
1686 po->stats.tp_drops++;
1687 atomic_inc(&sk->sk_drops);
1688 spin_unlock(&sk->sk_receive_queue.lock);
1689
1690 drop_n_restore:
1691 if (skb_head != skb->data && skb_shared(skb)) {
1692 skb->data = skb_head;
1693 skb->len = skb_len;
1694 }
1695 drop:
1696 consume_skb(skb);
1697 return 0;
1698 }
1699
1700 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1701 struct packet_type *pt, struct net_device *orig_dev)
1702 {
1703 struct sock *sk;
1704 struct packet_sock *po;
1705 struct sockaddr_ll *sll;
1706 union {
1707 struct tpacket_hdr *h1;
1708 struct tpacket2_hdr *h2;
1709 struct tpacket3_hdr *h3;
1710 void *raw;
1711 } h;
1712 u8 *skb_head = skb->data;
1713 int skb_len = skb->len;
1714 unsigned int snaplen, res;
1715 unsigned long status = TP_STATUS_USER;
1716 unsigned short macoff, netoff, hdrlen;
1717 struct sk_buff *copy_skb = NULL;
1718 struct timeval tv;
1719 struct timespec ts;
1720 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1721
1722 if (skb->pkt_type == PACKET_LOOPBACK)
1723 goto drop;
1724
1725 sk = pt->af_packet_priv;
1726 po = pkt_sk(sk);
1727
1728 if (!net_eq(dev_net(dev), sock_net(sk)))
1729 goto drop;
1730
1731 if (dev->header_ops) {
1732 if (sk->sk_type != SOCK_DGRAM)
1733 skb_push(skb, skb->data - skb_mac_header(skb));
1734 else if (skb->pkt_type == PACKET_OUTGOING) {
1735 /* Special case: outgoing packets have ll header at head */
1736 skb_pull(skb, skb_network_offset(skb));
1737 }
1738 }
1739
1740 if (skb->ip_summed == CHECKSUM_PARTIAL)
1741 status |= TP_STATUS_CSUMNOTREADY;
1742
1743 snaplen = skb->len;
1744
1745 res = run_filter(skb, sk, snaplen);
1746 if (!res)
1747 goto drop_n_restore;
1748 if (snaplen > res)
1749 snaplen = res;
1750
1751 if (sk->sk_type == SOCK_DGRAM) {
1752 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1753 po->tp_reserve;
1754 } else {
1755 unsigned maclen = skb_network_offset(skb);
1756 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1757 (maclen < 16 ? 16 : maclen)) +
1758 po->tp_reserve;
1759 macoff = netoff - maclen;
1760 }
1761 if (po->tp_version <= TPACKET_V2) {
1762 if (macoff + snaplen > po->rx_ring.frame_size) {
1763 if (po->copy_thresh &&
1764 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1765 if (skb_shared(skb)) {
1766 copy_skb = skb_clone(skb, GFP_ATOMIC);
1767 } else {
1768 copy_skb = skb_get(skb);
1769 skb_head = skb->data;
1770 }
1771 if (copy_skb)
1772 skb_set_owner_r(copy_skb, sk);
1773 }
1774 snaplen = po->rx_ring.frame_size - macoff;
1775 if ((int)snaplen < 0)
1776 snaplen = 0;
1777 }
1778 }
1779 spin_lock(&sk->sk_receive_queue.lock);
1780 h.raw = packet_current_rx_frame(po, skb,
1781 TP_STATUS_KERNEL, (macoff+snaplen));
1782 if (!h.raw)
1783 goto ring_is_full;
1784 if (po->tp_version <= TPACKET_V2) {
1785 packet_increment_rx_head(po, &po->rx_ring);
1786 /*
1787 * LOSING will be reported till you read the stats,
1788 * because it's COR - Clear On Read.
1789 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1790 * at packet level.
1791 */
1792 if (po->stats.tp_drops)
1793 status |= TP_STATUS_LOSING;
1794 }
1795 po->stats.tp_packets++;
1796 if (copy_skb) {
1797 status |= TP_STATUS_COPY;
1798 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1799 }
1800 spin_unlock(&sk->sk_receive_queue.lock);
1801
1802 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1803
1804 switch (po->tp_version) {
1805 case TPACKET_V1:
1806 h.h1->tp_len = skb->len;
1807 h.h1->tp_snaplen = snaplen;
1808 h.h1->tp_mac = macoff;
1809 h.h1->tp_net = netoff;
1810 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1811 && shhwtstamps->syststamp.tv64)
1812 tv = ktime_to_timeval(shhwtstamps->syststamp);
1813 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1814 && shhwtstamps->hwtstamp.tv64)
1815 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1816 else if (skb->tstamp.tv64)
1817 tv = ktime_to_timeval(skb->tstamp);
1818 else
1819 do_gettimeofday(&tv);
1820 h.h1->tp_sec = tv.tv_sec;
1821 h.h1->tp_usec = tv.tv_usec;
1822 hdrlen = sizeof(*h.h1);
1823 break;
1824 case TPACKET_V2:
1825 h.h2->tp_len = skb->len;
1826 h.h2->tp_snaplen = snaplen;
1827 h.h2->tp_mac = macoff;
1828 h.h2->tp_net = netoff;
1829 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1830 && shhwtstamps->syststamp.tv64)
1831 ts = ktime_to_timespec(shhwtstamps->syststamp);
1832 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1833 && shhwtstamps->hwtstamp.tv64)
1834 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1835 else if (skb->tstamp.tv64)
1836 ts = ktime_to_timespec(skb->tstamp);
1837 else
1838 getnstimeofday(&ts);
1839 h.h2->tp_sec = ts.tv_sec;
1840 h.h2->tp_nsec = ts.tv_nsec;
1841 if (vlan_tx_tag_present(skb)) {
1842 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1843 status |= TP_STATUS_VLAN_VALID;
1844 } else {
1845 h.h2->tp_vlan_tci = 0;
1846 }
1847 h.h2->tp_padding = 0;
1848 hdrlen = sizeof(*h.h2);
1849 break;
1850 case TPACKET_V3:
1851 /* tp_nxt_offset,vlan are already populated above.
1852 * So DONT clear those fields here
1853 */
1854 h.h3->tp_status |= status;
1855 h.h3->tp_len = skb->len;
1856 h.h3->tp_snaplen = snaplen;
1857 h.h3->tp_mac = macoff;
1858 h.h3->tp_net = netoff;
1859 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1860 && shhwtstamps->syststamp.tv64)
1861 ts = ktime_to_timespec(shhwtstamps->syststamp);
1862 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1863 && shhwtstamps->hwtstamp.tv64)
1864 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1865 else if (skb->tstamp.tv64)
1866 ts = ktime_to_timespec(skb->tstamp);
1867 else
1868 getnstimeofday(&ts);
1869 h.h3->tp_sec = ts.tv_sec;
1870 h.h3->tp_nsec = ts.tv_nsec;
1871 hdrlen = sizeof(*h.h3);
1872 break;
1873 default:
1874 BUG();
1875 }
1876
1877 sll = h.raw + TPACKET_ALIGN(hdrlen);
1878 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1879 sll->sll_family = AF_PACKET;
1880 sll->sll_hatype = dev->type;
1881 sll->sll_protocol = skb->protocol;
1882 sll->sll_pkttype = skb->pkt_type;
1883 if (unlikely(po->origdev))
1884 sll->sll_ifindex = orig_dev->ifindex;
1885 else
1886 sll->sll_ifindex = dev->ifindex;
1887
1888 smp_mb();
1889 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1890 {
1891 u8 *start, *end;
1892
1893 if (po->tp_version <= TPACKET_V2) {
1894 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1895 + macoff + snaplen);
1896 for (start = h.raw; start < end; start += PAGE_SIZE)
1897 flush_dcache_page(pgv_to_page(start));
1898 }
1899 smp_wmb();
1900 }
1901 #endif
1902 if (po->tp_version <= TPACKET_V2)
1903 __packet_set_status(po, h.raw, status);
1904 else
1905 prb_clear_blk_fill_status(&po->rx_ring);
1906
1907 sk->sk_data_ready(sk, 0);
1908
1909 drop_n_restore:
1910 if (skb_head != skb->data && skb_shared(skb)) {
1911 skb->data = skb_head;
1912 skb->len = skb_len;
1913 }
1914 drop:
1915 kfree_skb(skb);
1916 return 0;
1917
1918 ring_is_full:
1919 po->stats.tp_drops++;
1920 spin_unlock(&sk->sk_receive_queue.lock);
1921
1922 sk->sk_data_ready(sk, 0);
1923 kfree_skb(copy_skb);
1924 goto drop_n_restore;
1925 }
1926
1927 static void tpacket_destruct_skb(struct sk_buff *skb)
1928 {
1929 struct packet_sock *po = pkt_sk(skb->sk);
1930 void *ph;
1931
1932 if (likely(po->tx_ring.pg_vec)) {
1933 ph = skb_shinfo(skb)->destructor_arg;
1934 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
1935 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1936 atomic_dec(&po->tx_ring.pending);
1937 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1938 }
1939
1940 sock_wfree(skb);
1941 }
1942
1943 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1944 void *frame, struct net_device *dev, int size_max,
1945 __be16 proto, unsigned char *addr)
1946 {
1947 union {
1948 struct tpacket_hdr *h1;
1949 struct tpacket2_hdr *h2;
1950 void *raw;
1951 } ph;
1952 int to_write, offset, len, tp_len, nr_frags, len_max;
1953 struct socket *sock = po->sk.sk_socket;
1954 struct page *page;
1955 void *data;
1956 int err;
1957
1958 ph.raw = frame;
1959
1960 skb->protocol = proto;
1961 skb->dev = dev;
1962 skb->priority = po->sk.sk_priority;
1963 skb->mark = po->sk.sk_mark;
1964 skb_shinfo(skb)->destructor_arg = ph.raw;
1965
1966 switch (po->tp_version) {
1967 case TPACKET_V2:
1968 tp_len = ph.h2->tp_len;
1969 break;
1970 default:
1971 tp_len = ph.h1->tp_len;
1972 break;
1973 }
1974 if (unlikely(tp_len > size_max)) {
1975 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1976 return -EMSGSIZE;
1977 }
1978
1979 skb_reserve(skb, LL_RESERVED_SPACE(dev));
1980 skb_reset_network_header(skb);
1981
1982 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1983 to_write = tp_len;
1984
1985 if (sock->type == SOCK_DGRAM) {
1986 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1987 NULL, tp_len);
1988 if (unlikely(err < 0))
1989 return -EINVAL;
1990 } else if (dev->hard_header_len) {
1991 /* net device doesn't like empty head */
1992 if (unlikely(tp_len <= dev->hard_header_len)) {
1993 pr_err("packet size is too short (%d < %d)\n",
1994 tp_len, dev->hard_header_len);
1995 return -EINVAL;
1996 }
1997
1998 skb_push(skb, dev->hard_header_len);
1999 err = skb_store_bits(skb, 0, data,
2000 dev->hard_header_len);
2001 if (unlikely(err))
2002 return err;
2003
2004 data += dev->hard_header_len;
2005 to_write -= dev->hard_header_len;
2006 }
2007
2008 err = -EFAULT;
2009 offset = offset_in_page(data);
2010 len_max = PAGE_SIZE - offset;
2011 len = ((to_write > len_max) ? len_max : to_write);
2012
2013 skb->data_len = to_write;
2014 skb->len += to_write;
2015 skb->truesize += to_write;
2016 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2017
2018 while (likely(to_write)) {
2019 nr_frags = skb_shinfo(skb)->nr_frags;
2020
2021 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2022 pr_err("Packet exceed the number of skb frags(%lu)\n",
2023 MAX_SKB_FRAGS);
2024 return -EFAULT;
2025 }
2026
2027 page = pgv_to_page(data);
2028 data += len;
2029 flush_dcache_page(page);
2030 get_page(page);
2031 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2032 to_write -= len;
2033 offset = 0;
2034 len_max = PAGE_SIZE;
2035 len = ((to_write > len_max) ? len_max : to_write);
2036 }
2037
2038 return tp_len;
2039 }
2040
2041 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2042 {
2043 struct sk_buff *skb;
2044 struct net_device *dev;
2045 __be16 proto;
2046 bool need_rls_dev = false;
2047 int err, reserve = 0;
2048 void *ph;
2049 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2050 int tp_len, size_max;
2051 unsigned char *addr;
2052 int len_sum = 0;
2053 int status = 0;
2054
2055 mutex_lock(&po->pg_vec_lock);
2056
2057 err = -EBUSY;
2058 if (saddr == NULL) {
2059 dev = po->prot_hook.dev;
2060 proto = po->num;
2061 addr = NULL;
2062 } else {
2063 err = -EINVAL;
2064 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2065 goto out;
2066 if (msg->msg_namelen < (saddr->sll_halen
2067 + offsetof(struct sockaddr_ll,
2068 sll_addr)))
2069 goto out;
2070 proto = saddr->sll_protocol;
2071 addr = saddr->sll_addr;
2072 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2073 need_rls_dev = true;
2074 }
2075
2076 err = -ENXIO;
2077 if (unlikely(dev == NULL))
2078 goto out;
2079
2080 reserve = dev->hard_header_len;
2081
2082 err = -ENETDOWN;
2083 if (unlikely(!(dev->flags & IFF_UP)))
2084 goto out_put;
2085
2086 size_max = po->tx_ring.frame_size
2087 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2088
2089 if (size_max > dev->mtu + reserve)
2090 size_max = dev->mtu + reserve;
2091
2092 do {
2093 ph = packet_current_frame(po, &po->tx_ring,
2094 TP_STATUS_SEND_REQUEST);
2095
2096 if (unlikely(ph == NULL)) {
2097 schedule();
2098 continue;
2099 }
2100
2101 status = TP_STATUS_SEND_REQUEST;
2102 skb = sock_alloc_send_skb(&po->sk,
2103 LL_ALLOCATED_SPACE(dev)
2104 + sizeof(struct sockaddr_ll),
2105 0, &err);
2106
2107 if (unlikely(skb == NULL))
2108 goto out_status;
2109
2110 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2111 addr);
2112
2113 if (unlikely(tp_len < 0)) {
2114 if (po->tp_loss) {
2115 __packet_set_status(po, ph,
2116 TP_STATUS_AVAILABLE);
2117 packet_increment_head(&po->tx_ring);
2118 kfree_skb(skb);
2119 continue;
2120 } else {
2121 status = TP_STATUS_WRONG_FORMAT;
2122 err = tp_len;
2123 goto out_status;
2124 }
2125 }
2126
2127 skb->destructor = tpacket_destruct_skb;
2128 __packet_set_status(po, ph, TP_STATUS_SENDING);
2129 atomic_inc(&po->tx_ring.pending);
2130
2131 status = TP_STATUS_SEND_REQUEST;
2132 err = dev_queue_xmit(skb);
2133 if (unlikely(err > 0)) {
2134 err = net_xmit_errno(err);
2135 if (err && __packet_get_status(po, ph) ==
2136 TP_STATUS_AVAILABLE) {
2137 /* skb was destructed already */
2138 skb = NULL;
2139 goto out_status;
2140 }
2141 /*
2142 * skb was dropped but not destructed yet;
2143 * let's treat it like congestion or err < 0
2144 */
2145 err = 0;
2146 }
2147 packet_increment_head(&po->tx_ring);
2148 len_sum += tp_len;
2149 } while (likely((ph != NULL) ||
2150 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2151 (atomic_read(&po->tx_ring.pending))))
2152 );
2153
2154 err = len_sum;
2155 goto out_put;
2156
2157 out_status:
2158 __packet_set_status(po, ph, status);
2159 kfree_skb(skb);
2160 out_put:
2161 if (need_rls_dev)
2162 dev_put(dev);
2163 out:
2164 mutex_unlock(&po->pg_vec_lock);
2165 return err;
2166 }
2167
2168 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2169 size_t reserve, size_t len,
2170 size_t linear, int noblock,
2171 int *err)
2172 {
2173 struct sk_buff *skb;
2174
2175 /* Under a page? Don't bother with paged skb. */
2176 if (prepad + len < PAGE_SIZE || !linear)
2177 linear = len;
2178
2179 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2180 err);
2181 if (!skb)
2182 return NULL;
2183
2184 skb_reserve(skb, reserve);
2185 skb_put(skb, linear);
2186 skb->data_len = len - linear;
2187 skb->len += len - linear;
2188
2189 return skb;
2190 }
2191
2192 static int packet_snd(struct socket *sock,
2193 struct msghdr *msg, size_t len)
2194 {
2195 struct sock *sk = sock->sk;
2196 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2197 struct sk_buff *skb;
2198 struct net_device *dev;
2199 __be16 proto;
2200 bool need_rls_dev = false;
2201 unsigned char *addr;
2202 int err, reserve = 0;
2203 struct virtio_net_hdr vnet_hdr = { 0 };
2204 int offset = 0;
2205 int vnet_hdr_len;
2206 struct packet_sock *po = pkt_sk(sk);
2207 unsigned short gso_type = 0;
2208
2209 /*
2210 * Get and verify the address.
2211 */
2212
2213 if (saddr == NULL) {
2214 dev = po->prot_hook.dev;
2215 proto = po->num;
2216 addr = NULL;
2217 } else {
2218 err = -EINVAL;
2219 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2220 goto out;
2221 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2222 goto out;
2223 proto = saddr->sll_protocol;
2224 addr = saddr->sll_addr;
2225 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2226 need_rls_dev = true;
2227 }
2228
2229 err = -ENXIO;
2230 if (dev == NULL)
2231 goto out_unlock;
2232 if (sock->type == SOCK_RAW)
2233 reserve = dev->hard_header_len;
2234
2235 err = -ENETDOWN;
2236 if (!(dev->flags & IFF_UP))
2237 goto out_unlock;
2238
2239 if (po->has_vnet_hdr) {
2240 vnet_hdr_len = sizeof(vnet_hdr);
2241
2242 err = -EINVAL;
2243 if (len < vnet_hdr_len)
2244 goto out_unlock;
2245
2246 len -= vnet_hdr_len;
2247
2248 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2249 vnet_hdr_len);
2250 if (err < 0)
2251 goto out_unlock;
2252
2253 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2254 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2255 vnet_hdr.hdr_len))
2256 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2257 vnet_hdr.csum_offset + 2;
2258
2259 err = -EINVAL;
2260 if (vnet_hdr.hdr_len > len)
2261 goto out_unlock;
2262
2263 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2264 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2265 case VIRTIO_NET_HDR_GSO_TCPV4:
2266 gso_type = SKB_GSO_TCPV4;
2267 break;
2268 case VIRTIO_NET_HDR_GSO_TCPV6:
2269 gso_type = SKB_GSO_TCPV6;
2270 break;
2271 case VIRTIO_NET_HDR_GSO_UDP:
2272 gso_type = SKB_GSO_UDP;
2273 break;
2274 default:
2275 goto out_unlock;
2276 }
2277
2278 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2279 gso_type |= SKB_GSO_TCP_ECN;
2280
2281 if (vnet_hdr.gso_size == 0)
2282 goto out_unlock;
2283
2284 }
2285 }
2286
2287 err = -EMSGSIZE;
2288 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
2289 goto out_unlock;
2290
2291 err = -ENOBUFS;
2292 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
2293 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
2294 msg->msg_flags & MSG_DONTWAIT, &err);
2295 if (skb == NULL)
2296 goto out_unlock;
2297
2298 skb_set_network_header(skb, reserve);
2299
2300 err = -EINVAL;
2301 if (sock->type == SOCK_DGRAM &&
2302 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2303 goto out_free;
2304
2305 /* Returns -EFAULT on error */
2306 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2307 if (err)
2308 goto out_free;
2309 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2310 if (err < 0)
2311 goto out_free;
2312
2313 if (!gso_type && (len > dev->mtu + reserve)) {
2314 /* Earlier code assumed this would be a VLAN pkt,
2315 * double-check this now that we have the actual
2316 * packet in hand.
2317 */
2318 struct ethhdr *ehdr;
2319 skb_reset_mac_header(skb);
2320 ehdr = eth_hdr(skb);
2321 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2322 err = -EMSGSIZE;
2323 goto out_free;
2324 }
2325 }
2326
2327 skb->protocol = proto;
2328 skb->dev = dev;
2329 skb->priority = sk->sk_priority;
2330 skb->mark = sk->sk_mark;
2331
2332 if (po->has_vnet_hdr) {
2333 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2334 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2335 vnet_hdr.csum_offset)) {
2336 err = -EINVAL;
2337 goto out_free;
2338 }
2339 }
2340
2341 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2342 skb_shinfo(skb)->gso_type = gso_type;
2343
2344 /* Header must be checked, and gso_segs computed. */
2345 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2346 skb_shinfo(skb)->gso_segs = 0;
2347
2348 len += vnet_hdr_len;
2349 }
2350
2351 /*
2352 * Now send it
2353 */
2354
2355 err = dev_queue_xmit(skb);
2356 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2357 goto out_unlock;
2358
2359 if (need_rls_dev)
2360 dev_put(dev);
2361
2362 return len;
2363
2364 out_free:
2365 kfree_skb(skb);
2366 out_unlock:
2367 if (dev && need_rls_dev)
2368 dev_put(dev);
2369 out:
2370 return err;
2371 }
2372
2373 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2374 struct msghdr *msg, size_t len)
2375 {
2376 struct sock *sk = sock->sk;
2377 struct packet_sock *po = pkt_sk(sk);
2378 if (po->tx_ring.pg_vec)
2379 return tpacket_snd(po, msg);
2380 else
2381 return packet_snd(sock, msg, len);
2382 }
2383
2384 /*
2385 * Close a PACKET socket. This is fairly simple. We immediately go
2386 * to 'closed' state and remove our protocol entry in the device list.
2387 */
2388
2389 static int packet_release(struct socket *sock)
2390 {
2391 struct sock *sk = sock->sk;
2392 struct packet_sock *po;
2393 struct net *net;
2394 union tpacket_req_u req_u;
2395
2396 if (!sk)
2397 return 0;
2398
2399 net = sock_net(sk);
2400 po = pkt_sk(sk);
2401
2402 spin_lock_bh(&net->packet.sklist_lock);
2403 sk_del_node_init_rcu(sk);
2404 sock_prot_inuse_add(net, sk->sk_prot, -1);
2405 spin_unlock_bh(&net->packet.sklist_lock);
2406
2407 spin_lock(&po->bind_lock);
2408 unregister_prot_hook(sk, false);
2409 if (po->prot_hook.dev) {
2410 dev_put(po->prot_hook.dev);
2411 po->prot_hook.dev = NULL;
2412 }
2413 spin_unlock(&po->bind_lock);
2414
2415 packet_flush_mclist(sk);
2416
2417 memset(&req_u, 0, sizeof(req_u));
2418
2419 if (po->rx_ring.pg_vec)
2420 packet_set_ring(sk, &req_u, 1, 0);
2421
2422 if (po->tx_ring.pg_vec)
2423 packet_set_ring(sk, &req_u, 1, 1);
2424
2425 fanout_release(sk);
2426
2427 synchronize_net();
2428 /*
2429 * Now the socket is dead. No more input will appear.
2430 */
2431 sock_orphan(sk);
2432 sock->sk = NULL;
2433
2434 /* Purge queues */
2435
2436 skb_queue_purge(&sk->sk_receive_queue);
2437 sk_refcnt_debug_release(sk);
2438
2439 sock_put(sk);
2440 return 0;
2441 }
2442
2443 /*
2444 * Attach a packet hook.
2445 */
2446
2447 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2448 {
2449 struct packet_sock *po = pkt_sk(sk);
2450
2451 if (po->fanout)
2452 return -EINVAL;
2453
2454 lock_sock(sk);
2455
2456 spin_lock(&po->bind_lock);
2457 unregister_prot_hook(sk, true);
2458 po->num = protocol;
2459 po->prot_hook.type = protocol;
2460 if (po->prot_hook.dev)
2461 dev_put(po->prot_hook.dev);
2462 po->prot_hook.dev = dev;
2463
2464 po->ifindex = dev ? dev->ifindex : 0;
2465
2466 if (protocol == 0)
2467 goto out_unlock;
2468
2469 if (!dev || (dev->flags & IFF_UP)) {
2470 register_prot_hook(sk);
2471 } else {
2472 sk->sk_err = ENETDOWN;
2473 if (!sock_flag(sk, SOCK_DEAD))
2474 sk->sk_error_report(sk);
2475 }
2476
2477 out_unlock:
2478 spin_unlock(&po->bind_lock);
2479 release_sock(sk);
2480 return 0;
2481 }
2482
2483 /*
2484 * Bind a packet socket to a device
2485 */
2486
2487 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2488 int addr_len)
2489 {
2490 struct sock *sk = sock->sk;
2491 char name[15];
2492 struct net_device *dev;
2493 int err = -ENODEV;
2494
2495 /*
2496 * Check legality
2497 */
2498
2499 if (addr_len != sizeof(struct sockaddr))
2500 return -EINVAL;
2501 strlcpy(name, uaddr->sa_data, sizeof(name));
2502
2503 dev = dev_get_by_name(sock_net(sk), name);
2504 if (dev)
2505 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2506 return err;
2507 }
2508
2509 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2510 {
2511 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2512 struct sock *sk = sock->sk;
2513 struct net_device *dev = NULL;
2514 int err;
2515
2516
2517 /*
2518 * Check legality
2519 */
2520
2521 if (addr_len < sizeof(struct sockaddr_ll))
2522 return -EINVAL;
2523 if (sll->sll_family != AF_PACKET)
2524 return -EINVAL;
2525
2526 if (sll->sll_ifindex) {
2527 err = -ENODEV;
2528 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2529 if (dev == NULL)
2530 goto out;
2531 }
2532 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2533
2534 out:
2535 return err;
2536 }
2537
2538 static struct proto packet_proto = {
2539 .name = "PACKET",
2540 .owner = THIS_MODULE,
2541 .obj_size = sizeof(struct packet_sock),
2542 };
2543
2544 /*
2545 * Create a packet of type SOCK_PACKET.
2546 */
2547
2548 static int packet_create(struct net *net, struct socket *sock, int protocol,
2549 int kern)
2550 {
2551 struct sock *sk;
2552 struct packet_sock *po;
2553 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2554 int err;
2555
2556 if (!capable(CAP_NET_RAW))
2557 return -EPERM;
2558 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2559 sock->type != SOCK_PACKET)
2560 return -ESOCKTNOSUPPORT;
2561
2562 sock->state = SS_UNCONNECTED;
2563
2564 err = -ENOBUFS;
2565 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2566 if (sk == NULL)
2567 goto out;
2568
2569 sock->ops = &packet_ops;
2570 if (sock->type == SOCK_PACKET)
2571 sock->ops = &packet_ops_spkt;
2572
2573 sock_init_data(sock, sk);
2574
2575 po = pkt_sk(sk);
2576 sk->sk_family = PF_PACKET;
2577 po->num = proto;
2578
2579 sk->sk_destruct = packet_sock_destruct;
2580 sk_refcnt_debug_inc(sk);
2581
2582 /*
2583 * Attach a protocol block
2584 */
2585
2586 spin_lock_init(&po->bind_lock);
2587 mutex_init(&po->pg_vec_lock);
2588 po->prot_hook.func = packet_rcv;
2589
2590 if (sock->type == SOCK_PACKET)
2591 po->prot_hook.func = packet_rcv_spkt;
2592
2593 po->prot_hook.af_packet_priv = sk;
2594
2595 if (proto) {
2596 po->prot_hook.type = proto;
2597 register_prot_hook(sk);
2598 }
2599
2600 spin_lock_bh(&net->packet.sklist_lock);
2601 sk_add_node_rcu(sk, &net->packet.sklist);
2602 sock_prot_inuse_add(net, &packet_proto, 1);
2603 spin_unlock_bh(&net->packet.sklist_lock);
2604
2605 return 0;
2606 out:
2607 return err;
2608 }
2609
2610 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2611 {
2612 struct sock_exterr_skb *serr;
2613 struct sk_buff *skb, *skb2;
2614 int copied, err;
2615
2616 err = -EAGAIN;
2617 skb = skb_dequeue(&sk->sk_error_queue);
2618 if (skb == NULL)
2619 goto out;
2620
2621 copied = skb->len;
2622 if (copied > len) {
2623 msg->msg_flags |= MSG_TRUNC;
2624 copied = len;
2625 }
2626 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2627 if (err)
2628 goto out_free_skb;
2629
2630 sock_recv_timestamp(msg, sk, skb);
2631
2632 serr = SKB_EXT_ERR(skb);
2633 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2634 sizeof(serr->ee), &serr->ee);
2635
2636 msg->msg_flags |= MSG_ERRQUEUE;
2637 err = copied;
2638
2639 /* Reset and regenerate socket error */
2640 spin_lock_bh(&sk->sk_error_queue.lock);
2641 sk->sk_err = 0;
2642 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2643 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2644 spin_unlock_bh(&sk->sk_error_queue.lock);
2645 sk->sk_error_report(sk);
2646 } else
2647 spin_unlock_bh(&sk->sk_error_queue.lock);
2648
2649 out_free_skb:
2650 kfree_skb(skb);
2651 out:
2652 return err;
2653 }
2654
2655 /*
2656 * Pull a packet from our receive queue and hand it to the user.
2657 * If necessary we block.
2658 */
2659
2660 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2661 struct msghdr *msg, size_t len, int flags)
2662 {
2663 struct sock *sk = sock->sk;
2664 struct sk_buff *skb;
2665 int copied, err;
2666 struct sockaddr_ll *sll;
2667 int vnet_hdr_len = 0;
2668
2669 err = -EINVAL;
2670 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2671 goto out;
2672
2673 #if 0
2674 /* What error should we return now? EUNATTACH? */
2675 if (pkt_sk(sk)->ifindex < 0)
2676 return -ENODEV;
2677 #endif
2678
2679 if (flags & MSG_ERRQUEUE) {
2680 err = packet_recv_error(sk, msg, len);
2681 goto out;
2682 }
2683
2684 /*
2685 * Call the generic datagram receiver. This handles all sorts
2686 * of horrible races and re-entrancy so we can forget about it
2687 * in the protocol layers.
2688 *
2689 * Now it will return ENETDOWN, if device have just gone down,
2690 * but then it will block.
2691 */
2692
2693 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2694
2695 /*
2696 * An error occurred so return it. Because skb_recv_datagram()
2697 * handles the blocking we don't see and worry about blocking
2698 * retries.
2699 */
2700
2701 if (skb == NULL)
2702 goto out;
2703
2704 if (pkt_sk(sk)->has_vnet_hdr) {
2705 struct virtio_net_hdr vnet_hdr = { 0 };
2706
2707 err = -EINVAL;
2708 vnet_hdr_len = sizeof(vnet_hdr);
2709 if (len < vnet_hdr_len)
2710 goto out_free;
2711
2712 len -= vnet_hdr_len;
2713
2714 if (skb_is_gso(skb)) {
2715 struct skb_shared_info *sinfo = skb_shinfo(skb);
2716
2717 /* This is a hint as to how much should be linear. */
2718 vnet_hdr.hdr_len = skb_headlen(skb);
2719 vnet_hdr.gso_size = sinfo->gso_size;
2720 if (sinfo->gso_type & SKB_GSO_TCPV4)
2721 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2722 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2723 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2724 else if (sinfo->gso_type & SKB_GSO_UDP)
2725 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2726 else if (sinfo->gso_type & SKB_GSO_FCOE)
2727 goto out_free;
2728 else
2729 BUG();
2730 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2731 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2732 } else
2733 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2734
2735 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2736 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2737 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2738 vnet_hdr.csum_offset = skb->csum_offset;
2739 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2740 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2741 } /* else everything is zero */
2742
2743 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2744 vnet_hdr_len);
2745 if (err < 0)
2746 goto out_free;
2747 }
2748
2749 /*
2750 * If the address length field is there to be filled in, we fill
2751 * it in now.
2752 */
2753
2754 sll = &PACKET_SKB_CB(skb)->sa.ll;
2755 if (sock->type == SOCK_PACKET)
2756 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2757 else
2758 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2759
2760 /*
2761 * You lose any data beyond the buffer you gave. If it worries a
2762 * user program they can ask the device for its MTU anyway.
2763 */
2764
2765 copied = skb->len;
2766 if (copied > len) {
2767 copied = len;
2768 msg->msg_flags |= MSG_TRUNC;
2769 }
2770
2771 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2772 if (err)
2773 goto out_free;
2774
2775 sock_recv_ts_and_drops(msg, sk, skb);
2776
2777 if (msg->msg_name)
2778 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2779 msg->msg_namelen);
2780
2781 if (pkt_sk(sk)->auxdata) {
2782 struct tpacket_auxdata aux;
2783
2784 aux.tp_status = TP_STATUS_USER;
2785 if (skb->ip_summed == CHECKSUM_PARTIAL)
2786 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2787 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2788 aux.tp_snaplen = skb->len;
2789 aux.tp_mac = 0;
2790 aux.tp_net = skb_network_offset(skb);
2791 if (vlan_tx_tag_present(skb)) {
2792 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2793 aux.tp_status |= TP_STATUS_VLAN_VALID;
2794 } else {
2795 aux.tp_vlan_tci = 0;
2796 }
2797 aux.tp_padding = 0;
2798 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2799 }
2800
2801 /*
2802 * Free or return the buffer as appropriate. Again this
2803 * hides all the races and re-entrancy issues from us.
2804 */
2805 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2806
2807 out_free:
2808 skb_free_datagram(sk, skb);
2809 out:
2810 return err;
2811 }
2812
2813 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2814 int *uaddr_len, int peer)
2815 {
2816 struct net_device *dev;
2817 struct sock *sk = sock->sk;
2818
2819 if (peer)
2820 return -EOPNOTSUPP;
2821
2822 uaddr->sa_family = AF_PACKET;
2823 rcu_read_lock();
2824 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2825 if (dev)
2826 strncpy(uaddr->sa_data, dev->name, 14);
2827 else
2828 memset(uaddr->sa_data, 0, 14);
2829 rcu_read_unlock();
2830 *uaddr_len = sizeof(*uaddr);
2831
2832 return 0;
2833 }
2834
2835 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2836 int *uaddr_len, int peer)
2837 {
2838 struct net_device *dev;
2839 struct sock *sk = sock->sk;
2840 struct packet_sock *po = pkt_sk(sk);
2841 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2842
2843 if (peer)
2844 return -EOPNOTSUPP;
2845
2846 sll->sll_family = AF_PACKET;
2847 sll->sll_ifindex = po->ifindex;
2848 sll->sll_protocol = po->num;
2849 sll->sll_pkttype = 0;
2850 rcu_read_lock();
2851 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2852 if (dev) {
2853 sll->sll_hatype = dev->type;
2854 sll->sll_halen = dev->addr_len;
2855 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2856 } else {
2857 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2858 sll->sll_halen = 0;
2859 }
2860 rcu_read_unlock();
2861 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2862
2863 return 0;
2864 }
2865
2866 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2867 int what)
2868 {
2869 switch (i->type) {
2870 case PACKET_MR_MULTICAST:
2871 if (i->alen != dev->addr_len)
2872 return -EINVAL;
2873 if (what > 0)
2874 return dev_mc_add(dev, i->addr);
2875 else
2876 return dev_mc_del(dev, i->addr);
2877 break;
2878 case PACKET_MR_PROMISC:
2879 return dev_set_promiscuity(dev, what);
2880 break;
2881 case PACKET_MR_ALLMULTI:
2882 return dev_set_allmulti(dev, what);
2883 break;
2884 case PACKET_MR_UNICAST:
2885 if (i->alen != dev->addr_len)
2886 return -EINVAL;
2887 if (what > 0)
2888 return dev_uc_add(dev, i->addr);
2889 else
2890 return dev_uc_del(dev, i->addr);
2891 break;
2892 default:
2893 break;
2894 }
2895 return 0;
2896 }
2897
2898 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2899 {
2900 for ( ; i; i = i->next) {
2901 if (i->ifindex == dev->ifindex)
2902 packet_dev_mc(dev, i, what);
2903 }
2904 }
2905
2906 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2907 {
2908 struct packet_sock *po = pkt_sk(sk);
2909 struct packet_mclist *ml, *i;
2910 struct net_device *dev;
2911 int err;
2912
2913 rtnl_lock();
2914
2915 err = -ENODEV;
2916 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2917 if (!dev)
2918 goto done;
2919
2920 err = -EINVAL;
2921 if (mreq->mr_alen > dev->addr_len)
2922 goto done;
2923
2924 err = -ENOBUFS;
2925 i = kmalloc(sizeof(*i), GFP_KERNEL);
2926 if (i == NULL)
2927 goto done;
2928
2929 err = 0;
2930 for (ml = po->mclist; ml; ml = ml->next) {
2931 if (ml->ifindex == mreq->mr_ifindex &&
2932 ml->type == mreq->mr_type &&
2933 ml->alen == mreq->mr_alen &&
2934 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2935 ml->count++;
2936 /* Free the new element ... */
2937 kfree(i);
2938 goto done;
2939 }
2940 }
2941
2942 i->type = mreq->mr_type;
2943 i->ifindex = mreq->mr_ifindex;
2944 i->alen = mreq->mr_alen;
2945 memcpy(i->addr, mreq->mr_address, i->alen);
2946 i->count = 1;
2947 i->next = po->mclist;
2948 po->mclist = i;
2949 err = packet_dev_mc(dev, i, 1);
2950 if (err) {
2951 po->mclist = i->next;
2952 kfree(i);
2953 }
2954
2955 done:
2956 rtnl_unlock();
2957 return err;
2958 }
2959
2960 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2961 {
2962 struct packet_mclist *ml, **mlp;
2963
2964 rtnl_lock();
2965
2966 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2967 if (ml->ifindex == mreq->mr_ifindex &&
2968 ml->type == mreq->mr_type &&
2969 ml->alen == mreq->mr_alen &&
2970 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2971 if (--ml->count == 0) {
2972 struct net_device *dev;
2973 *mlp = ml->next;
2974 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2975 if (dev)
2976 packet_dev_mc(dev, ml, -1);
2977 kfree(ml);
2978 }
2979 rtnl_unlock();
2980 return 0;
2981 }
2982 }
2983 rtnl_unlock();
2984 return -EADDRNOTAVAIL;
2985 }
2986
2987 static void packet_flush_mclist(struct sock *sk)
2988 {
2989 struct packet_sock *po = pkt_sk(sk);
2990 struct packet_mclist *ml;
2991
2992 if (!po->mclist)
2993 return;
2994
2995 rtnl_lock();
2996 while ((ml = po->mclist) != NULL) {
2997 struct net_device *dev;
2998
2999 po->mclist = ml->next;
3000 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3001 if (dev != NULL)
3002 packet_dev_mc(dev, ml, -1);
3003 kfree(ml);
3004 }
3005 rtnl_unlock();
3006 }
3007
3008 static int
3009 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3010 {
3011 struct sock *sk = sock->sk;
3012 struct packet_sock *po = pkt_sk(sk);
3013 int ret;
3014
3015 if (level != SOL_PACKET)
3016 return -ENOPROTOOPT;
3017
3018 switch (optname) {
3019 case PACKET_ADD_MEMBERSHIP:
3020 case PACKET_DROP_MEMBERSHIP:
3021 {
3022 struct packet_mreq_max mreq;
3023 int len = optlen;
3024 memset(&mreq, 0, sizeof(mreq));
3025 if (len < sizeof(struct packet_mreq))
3026 return -EINVAL;
3027 if (len > sizeof(mreq))
3028 len = sizeof(mreq);
3029 if (copy_from_user(&mreq, optval, len))
3030 return -EFAULT;
3031 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3032 return -EINVAL;
3033 if (optname == PACKET_ADD_MEMBERSHIP)
3034 ret = packet_mc_add(sk, &mreq);
3035 else
3036 ret = packet_mc_drop(sk, &mreq);
3037 return ret;
3038 }
3039
3040 case PACKET_RX_RING:
3041 case PACKET_TX_RING:
3042 {
3043 union tpacket_req_u req_u;
3044 int len;
3045
3046 switch (po->tp_version) {
3047 case TPACKET_V1:
3048 case TPACKET_V2:
3049 len = sizeof(req_u.req);
3050 break;
3051 case TPACKET_V3:
3052 default:
3053 len = sizeof(req_u.req3);
3054 break;
3055 }
3056 if (optlen < len)
3057 return -EINVAL;
3058 if (pkt_sk(sk)->has_vnet_hdr)
3059 return -EINVAL;
3060 if (copy_from_user(&req_u.req, optval, len))
3061 return -EFAULT;
3062 return packet_set_ring(sk, &req_u, 0,
3063 optname == PACKET_TX_RING);
3064 }
3065 case PACKET_COPY_THRESH:
3066 {
3067 int val;
3068
3069 if (optlen != sizeof(val))
3070 return -EINVAL;
3071 if (copy_from_user(&val, optval, sizeof(val)))
3072 return -EFAULT;
3073
3074 pkt_sk(sk)->copy_thresh = val;
3075 return 0;
3076 }
3077 case PACKET_VERSION:
3078 {
3079 int val;
3080
3081 if (optlen != sizeof(val))
3082 return -EINVAL;
3083 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3084 return -EBUSY;
3085 if (copy_from_user(&val, optval, sizeof(val)))
3086 return -EFAULT;
3087 switch (val) {
3088 case TPACKET_V1:
3089 case TPACKET_V2:
3090 case TPACKET_V3:
3091 po->tp_version = val;
3092 return 0;
3093 default:
3094 return -EINVAL;
3095 }
3096 }
3097 case PACKET_RESERVE:
3098 {
3099 unsigned int val;
3100
3101 if (optlen != sizeof(val))
3102 return -EINVAL;
3103 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3104 return -EBUSY;
3105 if (copy_from_user(&val, optval, sizeof(val)))
3106 return -EFAULT;
3107 po->tp_reserve = val;
3108 return 0;
3109 }
3110 case PACKET_LOSS:
3111 {
3112 unsigned int val;
3113
3114 if (optlen != sizeof(val))
3115 return -EINVAL;
3116 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3117 return -EBUSY;
3118 if (copy_from_user(&val, optval, sizeof(val)))
3119 return -EFAULT;
3120 po->tp_loss = !!val;
3121 return 0;
3122 }
3123 case PACKET_AUXDATA:
3124 {
3125 int val;
3126
3127 if (optlen < sizeof(val))
3128 return -EINVAL;
3129 if (copy_from_user(&val, optval, sizeof(val)))
3130 return -EFAULT;
3131
3132 po->auxdata = !!val;
3133 return 0;
3134 }
3135 case PACKET_ORIGDEV:
3136 {
3137 int val;
3138
3139 if (optlen < sizeof(val))
3140 return -EINVAL;
3141 if (copy_from_user(&val, optval, sizeof(val)))
3142 return -EFAULT;
3143
3144 po->origdev = !!val;
3145 return 0;
3146 }
3147 case PACKET_VNET_HDR:
3148 {
3149 int val;
3150
3151 if (sock->type != SOCK_RAW)
3152 return -EINVAL;
3153 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3154 return -EBUSY;
3155 if (optlen < sizeof(val))
3156 return -EINVAL;
3157 if (copy_from_user(&val, optval, sizeof(val)))
3158 return -EFAULT;
3159
3160 po->has_vnet_hdr = !!val;
3161 return 0;
3162 }
3163 case PACKET_TIMESTAMP:
3164 {
3165 int val;
3166
3167 if (optlen != sizeof(val))
3168 return -EINVAL;
3169 if (copy_from_user(&val, optval, sizeof(val)))
3170 return -EFAULT;
3171
3172 po->tp_tstamp = val;
3173 return 0;
3174 }
3175 case PACKET_FANOUT:
3176 {
3177 int val;
3178
3179 if (optlen != sizeof(val))
3180 return -EINVAL;
3181 if (copy_from_user(&val, optval, sizeof(val)))
3182 return -EFAULT;
3183
3184 return fanout_add(sk, val & 0xffff, val >> 16);
3185 }
3186 default:
3187 return -ENOPROTOOPT;
3188 }
3189 }
3190
3191 static int packet_getsockopt(struct socket *sock, int level, int optname,
3192 char __user *optval, int __user *optlen)
3193 {
3194 int len;
3195 int val;
3196 struct sock *sk = sock->sk;
3197 struct packet_sock *po = pkt_sk(sk);
3198 void *data;
3199 struct tpacket_stats st;
3200 union tpacket_stats_u st_u;
3201
3202 if (level != SOL_PACKET)
3203 return -ENOPROTOOPT;
3204
3205 if (get_user(len, optlen))
3206 return -EFAULT;
3207
3208 if (len < 0)
3209 return -EINVAL;
3210
3211 switch (optname) {
3212 case PACKET_STATISTICS:
3213 if (po->tp_version == TPACKET_V3) {
3214 len = sizeof(struct tpacket_stats_v3);
3215 } else {
3216 if (len > sizeof(struct tpacket_stats))
3217 len = sizeof(struct tpacket_stats);
3218 }
3219 spin_lock_bh(&sk->sk_receive_queue.lock);
3220 if (po->tp_version == TPACKET_V3) {
3221 memcpy(&st_u.stats3, &po->stats,
3222 sizeof(struct tpacket_stats));
3223 st_u.stats3.tp_freeze_q_cnt =
3224 po->stats_u.stats3.tp_freeze_q_cnt;
3225 st_u.stats3.tp_packets += po->stats.tp_drops;
3226 data = &st_u.stats3;
3227 } else {
3228 st = po->stats;
3229 st.tp_packets += st.tp_drops;
3230 data = &st;
3231 }
3232 memset(&po->stats, 0, sizeof(st));
3233 spin_unlock_bh(&sk->sk_receive_queue.lock);
3234 break;
3235 case PACKET_AUXDATA:
3236 if (len > sizeof(int))
3237 len = sizeof(int);
3238 val = po->auxdata;
3239
3240 data = &val;
3241 break;
3242 case PACKET_ORIGDEV:
3243 if (len > sizeof(int))
3244 len = sizeof(int);
3245 val = po->origdev;
3246
3247 data = &val;
3248 break;
3249 case PACKET_VNET_HDR:
3250 if (len > sizeof(int))
3251 len = sizeof(int);
3252 val = po->has_vnet_hdr;
3253
3254 data = &val;
3255 break;
3256 case PACKET_VERSION:
3257 if (len > sizeof(int))
3258 len = sizeof(int);
3259 val = po->tp_version;
3260 data = &val;
3261 break;
3262 case PACKET_HDRLEN:
3263 if (len > sizeof(int))
3264 len = sizeof(int);
3265 if (copy_from_user(&val, optval, len))
3266 return -EFAULT;
3267 switch (val) {
3268 case TPACKET_V1:
3269 val = sizeof(struct tpacket_hdr);
3270 break;
3271 case TPACKET_V2:
3272 val = sizeof(struct tpacket2_hdr);
3273 break;
3274 case TPACKET_V3:
3275 val = sizeof(struct tpacket3_hdr);
3276 break;
3277 default:
3278 return -EINVAL;
3279 }
3280 data = &val;
3281 break;
3282 case PACKET_RESERVE:
3283 if (len > sizeof(unsigned int))
3284 len = sizeof(unsigned int);
3285 val = po->tp_reserve;
3286 data = &val;
3287 break;
3288 case PACKET_LOSS:
3289 if (len > sizeof(unsigned int))
3290 len = sizeof(unsigned int);
3291 val = po->tp_loss;
3292 data = &val;
3293 break;
3294 case PACKET_TIMESTAMP:
3295 if (len > sizeof(int))
3296 len = sizeof(int);
3297 val = po->tp_tstamp;
3298 data = &val;
3299 break;
3300 case PACKET_FANOUT:
3301 if (len > sizeof(int))
3302 len = sizeof(int);
3303 val = (po->fanout ?
3304 ((u32)po->fanout->id |
3305 ((u32)po->fanout->type << 16)) :
3306 0);
3307 data = &val;
3308 break;
3309 default:
3310 return -ENOPROTOOPT;
3311 }
3312
3313 if (put_user(len, optlen))
3314 return -EFAULT;
3315 if (copy_to_user(optval, data, len))
3316 return -EFAULT;
3317 return 0;
3318 }
3319
3320
3321 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3322 {
3323 struct sock *sk;
3324 struct hlist_node *node;
3325 struct net_device *dev = data;
3326 struct net *net = dev_net(dev);
3327
3328 rcu_read_lock();
3329 sk_for_each_rcu(sk, node, &net->packet.sklist) {
3330 struct packet_sock *po = pkt_sk(sk);
3331
3332 switch (msg) {
3333 case NETDEV_UNREGISTER:
3334 if (po->mclist)
3335 packet_dev_mclist(dev, po->mclist, -1);
3336 /* fallthrough */
3337
3338 case NETDEV_DOWN:
3339 if (dev->ifindex == po->ifindex) {
3340 spin_lock(&po->bind_lock);
3341 if (po->running) {
3342 __unregister_prot_hook(sk, false);
3343 sk->sk_err = ENETDOWN;
3344 if (!sock_flag(sk, SOCK_DEAD))
3345 sk->sk_error_report(sk);
3346 }
3347 if (msg == NETDEV_UNREGISTER) {
3348 po->ifindex = -1;
3349 if (po->prot_hook.dev)
3350 dev_put(po->prot_hook.dev);
3351 po->prot_hook.dev = NULL;
3352 }
3353 spin_unlock(&po->bind_lock);
3354 }
3355 break;
3356 case NETDEV_UP:
3357 if (dev->ifindex == po->ifindex) {
3358 spin_lock(&po->bind_lock);
3359 if (po->num)
3360 register_prot_hook(sk);
3361 spin_unlock(&po->bind_lock);
3362 }
3363 break;
3364 }
3365 }
3366 rcu_read_unlock();
3367 return NOTIFY_DONE;
3368 }
3369
3370
3371 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3372 unsigned long arg)
3373 {
3374 struct sock *sk = sock->sk;
3375
3376 switch (cmd) {
3377 case SIOCOUTQ:
3378 {
3379 int amount = sk_wmem_alloc_get(sk);
3380
3381 return put_user(amount, (int __user *)arg);
3382 }
3383 case SIOCINQ:
3384 {
3385 struct sk_buff *skb;
3386 int amount = 0;
3387
3388 spin_lock_bh(&sk->sk_receive_queue.lock);
3389 skb = skb_peek(&sk->sk_receive_queue);
3390 if (skb)
3391 amount = skb->len;
3392 spin_unlock_bh(&sk->sk_receive_queue.lock);
3393 return put_user(amount, (int __user *)arg);
3394 }
3395 case SIOCGSTAMP:
3396 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3397 case SIOCGSTAMPNS:
3398 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3399
3400 #ifdef CONFIG_INET
3401 case SIOCADDRT:
3402 case SIOCDELRT:
3403 case SIOCDARP:
3404 case SIOCGARP:
3405 case SIOCSARP:
3406 case SIOCGIFADDR:
3407 case SIOCSIFADDR:
3408 case SIOCGIFBRDADDR:
3409 case SIOCSIFBRDADDR:
3410 case SIOCGIFNETMASK:
3411 case SIOCSIFNETMASK:
3412 case SIOCGIFDSTADDR:
3413 case SIOCSIFDSTADDR:
3414 case SIOCSIFFLAGS:
3415 return inet_dgram_ops.ioctl(sock, cmd, arg);
3416 #endif
3417
3418 default:
3419 return -ENOIOCTLCMD;
3420 }
3421 return 0;
3422 }
3423
3424 static unsigned int packet_poll(struct file *file, struct socket *sock,
3425 poll_table *wait)
3426 {
3427 struct sock *sk = sock->sk;
3428 struct packet_sock *po = pkt_sk(sk);
3429 unsigned int mask = datagram_poll(file, sock, wait);
3430
3431 spin_lock_bh(&sk->sk_receive_queue.lock);
3432 if (po->rx_ring.pg_vec) {
3433 if (!packet_previous_rx_frame(po, &po->rx_ring,
3434 TP_STATUS_KERNEL))
3435 mask |= POLLIN | POLLRDNORM;
3436 }
3437 spin_unlock_bh(&sk->sk_receive_queue.lock);
3438 spin_lock_bh(&sk->sk_write_queue.lock);
3439 if (po->tx_ring.pg_vec) {
3440 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3441 mask |= POLLOUT | POLLWRNORM;
3442 }
3443 spin_unlock_bh(&sk->sk_write_queue.lock);
3444 return mask;
3445 }
3446
3447
3448 /* Dirty? Well, I still did not learn better way to account
3449 * for user mmaps.
3450 */
3451
3452 static void packet_mm_open(struct vm_area_struct *vma)
3453 {
3454 struct file *file = vma->vm_file;
3455 struct socket *sock = file->private_data;
3456 struct sock *sk = sock->sk;
3457
3458 if (sk)
3459 atomic_inc(&pkt_sk(sk)->mapped);
3460 }
3461
3462 static void packet_mm_close(struct vm_area_struct *vma)
3463 {
3464 struct file *file = vma->vm_file;
3465 struct socket *sock = file->private_data;
3466 struct sock *sk = sock->sk;
3467
3468 if (sk)
3469 atomic_dec(&pkt_sk(sk)->mapped);
3470 }
3471
3472 static const struct vm_operations_struct packet_mmap_ops = {
3473 .open = packet_mm_open,
3474 .close = packet_mm_close,
3475 };
3476
3477 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3478 unsigned int len)
3479 {
3480 int i;
3481
3482 for (i = 0; i < len; i++) {
3483 if (likely(pg_vec[i].buffer)) {
3484 if (is_vmalloc_addr(pg_vec[i].buffer))
3485 vfree(pg_vec[i].buffer);
3486 else
3487 free_pages((unsigned long)pg_vec[i].buffer,
3488 order);
3489 pg_vec[i].buffer = NULL;
3490 }
3491 }
3492 kfree(pg_vec);
3493 }
3494
3495 static char *alloc_one_pg_vec_page(unsigned long order)
3496 {
3497 char *buffer = NULL;
3498 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3499 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3500
3501 buffer = (char *) __get_free_pages(gfp_flags, order);
3502
3503 if (buffer)
3504 return buffer;
3505
3506 /*
3507 * __get_free_pages failed, fall back to vmalloc
3508 */
3509 buffer = vzalloc((1 << order) * PAGE_SIZE);
3510
3511 if (buffer)
3512 return buffer;
3513
3514 /*
3515 * vmalloc failed, lets dig into swap here
3516 */
3517 gfp_flags &= ~__GFP_NORETRY;
3518 buffer = (char *)__get_free_pages(gfp_flags, order);
3519 if (buffer)
3520 return buffer;
3521
3522 /*
3523 * complete and utter failure
3524 */
3525 return NULL;
3526 }
3527
3528 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3529 {
3530 unsigned int block_nr = req->tp_block_nr;
3531 struct pgv *pg_vec;
3532 int i;
3533
3534 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3535 if (unlikely(!pg_vec))
3536 goto out;
3537
3538 for (i = 0; i < block_nr; i++) {
3539 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3540 if (unlikely(!pg_vec[i].buffer))
3541 goto out_free_pgvec;
3542 }
3543
3544 out:
3545 return pg_vec;
3546
3547 out_free_pgvec:
3548 free_pg_vec(pg_vec, order, block_nr);
3549 pg_vec = NULL;
3550 goto out;
3551 }
3552
3553 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3554 int closing, int tx_ring)
3555 {
3556 struct pgv *pg_vec = NULL;
3557 struct packet_sock *po = pkt_sk(sk);
3558 int was_running, order = 0;
3559 struct packet_ring_buffer *rb;
3560 struct sk_buff_head *rb_queue;
3561 __be16 num;
3562 int err = -EINVAL;
3563 /* Added to avoid minimal code churn */
3564 struct tpacket_req *req = &req_u->req;
3565
3566 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3567 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3568 WARN(1, "Tx-ring is not supported.\n");
3569 goto out;
3570 }
3571
3572 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3573 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3574
3575 err = -EBUSY;
3576 if (!closing) {
3577 if (atomic_read(&po->mapped))
3578 goto out;
3579 if (atomic_read(&rb->pending))
3580 goto out;
3581 }
3582
3583 if (req->tp_block_nr) {
3584 /* Sanity tests and some calculations */
3585 err = -EBUSY;
3586 if (unlikely(rb->pg_vec))
3587 goto out;
3588
3589 switch (po->tp_version) {
3590 case TPACKET_V1:
3591 po->tp_hdrlen = TPACKET_HDRLEN;
3592 break;
3593 case TPACKET_V2:
3594 po->tp_hdrlen = TPACKET2_HDRLEN;
3595 break;
3596 case TPACKET_V3:
3597 po->tp_hdrlen = TPACKET3_HDRLEN;
3598 break;
3599 }
3600
3601 err = -EINVAL;
3602 if (unlikely((int)req->tp_block_size <= 0))
3603 goto out;
3604 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3605 goto out;
3606 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3607 po->tp_reserve))
3608 goto out;
3609 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3610 goto out;
3611
3612 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3613 if (unlikely(rb->frames_per_block <= 0))
3614 goto out;
3615 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3616 req->tp_frame_nr))
3617 goto out;
3618
3619 err = -ENOMEM;
3620 order = get_order(req->tp_block_size);
3621 pg_vec = alloc_pg_vec(req, order);
3622 if (unlikely(!pg_vec))
3623 goto out;
3624 switch (po->tp_version) {
3625 case TPACKET_V3:
3626 /* Transmit path is not supported. We checked
3627 * it above but just being paranoid
3628 */
3629 if (!tx_ring)
3630 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3631 break;
3632 default:
3633 break;
3634 }
3635 }
3636 /* Done */
3637 else {
3638 err = -EINVAL;
3639 if (unlikely(req->tp_frame_nr))
3640 goto out;
3641 }
3642
3643 lock_sock(sk);
3644
3645 /* Detach socket from network */
3646 spin_lock(&po->bind_lock);
3647 was_running = po->running;
3648 num = po->num;
3649 if (was_running) {
3650 po->num = 0;
3651 __unregister_prot_hook(sk, false);
3652 }
3653 spin_unlock(&po->bind_lock);
3654
3655 synchronize_net();
3656
3657 err = -EBUSY;
3658 mutex_lock(&po->pg_vec_lock);
3659 if (closing || atomic_read(&po->mapped) == 0) {
3660 err = 0;
3661 spin_lock_bh(&rb_queue->lock);
3662 swap(rb->pg_vec, pg_vec);
3663 rb->frame_max = (req->tp_frame_nr - 1);
3664 rb->head = 0;
3665 rb->frame_size = req->tp_frame_size;
3666 spin_unlock_bh(&rb_queue->lock);
3667
3668 swap(rb->pg_vec_order, order);
3669 swap(rb->pg_vec_len, req->tp_block_nr);
3670
3671 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3672 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3673 tpacket_rcv : packet_rcv;
3674 skb_queue_purge(rb_queue);
3675 if (atomic_read(&po->mapped))
3676 pr_err("packet_mmap: vma is busy: %d\n",
3677 atomic_read(&po->mapped));
3678 }
3679 mutex_unlock(&po->pg_vec_lock);
3680
3681 spin_lock(&po->bind_lock);
3682 if (was_running) {
3683 po->num = num;
3684 register_prot_hook(sk);
3685 }
3686 spin_unlock(&po->bind_lock);
3687 if (closing && (po->tp_version > TPACKET_V2)) {
3688 /* Because we don't support block-based V3 on tx-ring */
3689 if (!tx_ring)
3690 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3691 }
3692 release_sock(sk);
3693
3694 if (pg_vec)
3695 free_pg_vec(pg_vec, order, req->tp_block_nr);
3696 out:
3697 return err;
3698 }
3699
3700 static int packet_mmap(struct file *file, struct socket *sock,
3701 struct vm_area_struct *vma)
3702 {
3703 struct sock *sk = sock->sk;
3704 struct packet_sock *po = pkt_sk(sk);
3705 unsigned long size, expected_size;
3706 struct packet_ring_buffer *rb;
3707 unsigned long start;
3708 int err = -EINVAL;
3709 int i;
3710
3711 if (vma->vm_pgoff)
3712 return -EINVAL;
3713
3714 mutex_lock(&po->pg_vec_lock);
3715
3716 expected_size = 0;
3717 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3718 if (rb->pg_vec) {
3719 expected_size += rb->pg_vec_len
3720 * rb->pg_vec_pages
3721 * PAGE_SIZE;
3722 }
3723 }
3724
3725 if (expected_size == 0)
3726 goto out;
3727
3728 size = vma->vm_end - vma->vm_start;
3729 if (size != expected_size)
3730 goto out;
3731
3732 start = vma->vm_start;
3733 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3734 if (rb->pg_vec == NULL)
3735 continue;
3736
3737 for (i = 0; i < rb->pg_vec_len; i++) {
3738 struct page *page;
3739 void *kaddr = rb->pg_vec[i].buffer;
3740 int pg_num;
3741
3742 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3743 page = pgv_to_page(kaddr);
3744 err = vm_insert_page(vma, start, page);
3745 if (unlikely(err))
3746 goto out;
3747 start += PAGE_SIZE;
3748 kaddr += PAGE_SIZE;
3749 }
3750 }
3751 }
3752
3753 atomic_inc(&po->mapped);
3754 vma->vm_ops = &packet_mmap_ops;
3755 err = 0;
3756
3757 out:
3758 mutex_unlock(&po->pg_vec_lock);
3759 return err;
3760 }
3761
3762 static const struct proto_ops packet_ops_spkt = {
3763 .family = PF_PACKET,
3764 .owner = THIS_MODULE,
3765 .release = packet_release,
3766 .bind = packet_bind_spkt,
3767 .connect = sock_no_connect,
3768 .socketpair = sock_no_socketpair,
3769 .accept = sock_no_accept,
3770 .getname = packet_getname_spkt,
3771 .poll = datagram_poll,
3772 .ioctl = packet_ioctl,
3773 .listen = sock_no_listen,
3774 .shutdown = sock_no_shutdown,
3775 .setsockopt = sock_no_setsockopt,
3776 .getsockopt = sock_no_getsockopt,
3777 .sendmsg = packet_sendmsg_spkt,
3778 .recvmsg = packet_recvmsg,
3779 .mmap = sock_no_mmap,
3780 .sendpage = sock_no_sendpage,
3781 };
3782
3783 static const struct proto_ops packet_ops = {
3784 .family = PF_PACKET,
3785 .owner = THIS_MODULE,
3786 .release = packet_release,
3787 .bind = packet_bind,
3788 .connect = sock_no_connect,
3789 .socketpair = sock_no_socketpair,
3790 .accept = sock_no_accept,
3791 .getname = packet_getname,
3792 .poll = packet_poll,
3793 .ioctl = packet_ioctl,
3794 .listen = sock_no_listen,
3795 .shutdown = sock_no_shutdown,
3796 .setsockopt = packet_setsockopt,
3797 .getsockopt = packet_getsockopt,
3798 .sendmsg = packet_sendmsg,
3799 .recvmsg = packet_recvmsg,
3800 .mmap = packet_mmap,
3801 .sendpage = sock_no_sendpage,
3802 };
3803
3804 static const struct net_proto_family packet_family_ops = {
3805 .family = PF_PACKET,
3806 .create = packet_create,
3807 .owner = THIS_MODULE,
3808 };
3809
3810 static struct notifier_block packet_netdev_notifier = {
3811 .notifier_call = packet_notifier,
3812 };
3813
3814 #ifdef CONFIG_PROC_FS
3815
3816 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3817 __acquires(RCU)
3818 {
3819 struct net *net = seq_file_net(seq);
3820
3821 rcu_read_lock();
3822 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3823 }
3824
3825 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3826 {
3827 struct net *net = seq_file_net(seq);
3828 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3829 }
3830
3831 static void packet_seq_stop(struct seq_file *seq, void *v)
3832 __releases(RCU)
3833 {
3834 rcu_read_unlock();
3835 }
3836
3837 static int packet_seq_show(struct seq_file *seq, void *v)
3838 {
3839 if (v == SEQ_START_TOKEN)
3840 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3841 else {
3842 struct sock *s = sk_entry(v);
3843 const struct packet_sock *po = pkt_sk(s);
3844
3845 seq_printf(seq,
3846 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3847 s,
3848 atomic_read(&s->sk_refcnt),
3849 s->sk_type,
3850 ntohs(po->num),
3851 po->ifindex,
3852 po->running,
3853 atomic_read(&s->sk_rmem_alloc),
3854 sock_i_uid(s),
3855 sock_i_ino(s));
3856 }
3857
3858 return 0;
3859 }
3860
3861 static const struct seq_operations packet_seq_ops = {
3862 .start = packet_seq_start,
3863 .next = packet_seq_next,
3864 .stop = packet_seq_stop,
3865 .show = packet_seq_show,
3866 };
3867
3868 static int packet_seq_open(struct inode *inode, struct file *file)
3869 {
3870 return seq_open_net(inode, file, &packet_seq_ops,
3871 sizeof(struct seq_net_private));
3872 }
3873
3874 static const struct file_operations packet_seq_fops = {
3875 .owner = THIS_MODULE,
3876 .open = packet_seq_open,
3877 .read = seq_read,
3878 .llseek = seq_lseek,
3879 .release = seq_release_net,
3880 };
3881
3882 #endif
3883
3884 static int __net_init packet_net_init(struct net *net)
3885 {
3886 spin_lock_init(&net->packet.sklist_lock);
3887 INIT_HLIST_HEAD(&net->packet.sklist);
3888
3889 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3890 return -ENOMEM;
3891
3892 return 0;
3893 }
3894
3895 static void __net_exit packet_net_exit(struct net *net)
3896 {
3897 proc_net_remove(net, "packet");
3898 }
3899
3900 static struct pernet_operations packet_net_ops = {
3901 .init = packet_net_init,
3902 .exit = packet_net_exit,
3903 };
3904
3905
3906 static void __exit packet_exit(void)
3907 {
3908 unregister_netdevice_notifier(&packet_netdev_notifier);
3909 unregister_pernet_subsys(&packet_net_ops);
3910 sock_unregister(PF_PACKET);
3911 proto_unregister(&packet_proto);
3912 }
3913
3914 static int __init packet_init(void)
3915 {
3916 int rc = proto_register(&packet_proto, 0);
3917
3918 if (rc != 0)
3919 goto out;
3920
3921 sock_register(&packet_family_ops);
3922 register_pernet_subsys(&packet_net_ops);
3923 register_netdevice_notifier(&packet_netdev_notifier);
3924 out:
3925 return rc;
3926 }
3927
3928 module_init(packet_init);
3929 module_exit(packet_exit);
3930 MODULE_LICENSE("GPL");
3931 MODULE_ALIAS_NETPROTO(PF_PACKET);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree