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rps: fix insufficient bounds checking in store_rps_dev_flow_table_cnt()
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / packet / af_packet.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * PACKET - implements raw packet sockets.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 *
12 * Fixes:
13 * Alan Cox : verify_area() now used correctly
14 * Alan Cox : new skbuff lists, look ma no backlogs!
15 * Alan Cox : tidied skbuff lists.
16 * Alan Cox : Now uses generic datagram routines I
17 * added. Also fixed the peek/read crash
18 * from all old Linux datagram code.
19 * Alan Cox : Uses the improved datagram code.
20 * Alan Cox : Added NULL's for socket options.
21 * Alan Cox : Re-commented the code.
22 * Alan Cox : Use new kernel side addressing
23 * Rob Janssen : Correct MTU usage.
24 * Dave Platt : Counter leaks caused by incorrect
25 * interrupt locking and some slightly
26 * dubious gcc output. Can you read
27 * compiler: it said _VOLATILE_
28 * Richard Kooijman : Timestamp fixes.
29 * Alan Cox : New buffers. Use sk->mac.raw.
30 * Alan Cox : sendmsg/recvmsg support.
31 * Alan Cox : Protocol setting support
32 * Alexey Kuznetsov : Untied from IPv4 stack.
33 * Cyrus Durgin : Fixed kerneld for kmod.
34 * Michal Ostrowski : Module initialization cleanup.
35 * Ulises Alonso : Frame number limit removal and
36 * packet_set_ring memory leak.
37 * Eric Biederman : Allow for > 8 byte hardware addresses.
38 * The convention is that longer addresses
39 * will simply extend the hardware address
40 * byte arrays at the end of sockaddr_ll
41 * and packet_mreq.
42 * Johann Baudy : Added TX RING.
43 * Chetan Loke : Implemented TPACKET_V3 block abstraction
44 * layer.
45 * Copyright (C) 2011, <lokec@ccs.neu.edu>
46 *
47 *
48 * This program is free software; you can redistribute it and/or
49 * modify it under the terms of the GNU General Public License
50 * as published by the Free Software Foundation; either version
51 * 2 of the License, or (at your option) any later version.
52 *
53 */
54
55 #include <linux/types.h>
56 #include <linux/mm.h>
57 #include <linux/capability.h>
58 #include <linux/fcntl.h>
59 #include <linux/socket.h>
60 #include <linux/in.h>
61 #include <linux/inet.h>
62 #include <linux/netdevice.h>
63 #include <linux/if_packet.h>
64 #include <linux/wireless.h>
65 #include <linux/kernel.h>
66 #include <linux/kmod.h>
67 #include <linux/slab.h>
68 #include <linux/vmalloc.h>
69 #include <net/net_namespace.h>
70 #include <net/ip.h>
71 #include <net/protocol.h>
72 #include <linux/skbuff.h>
73 #include <net/sock.h>
74 #include <linux/errno.h>
75 #include <linux/timer.h>
76 #include <asm/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) + skb->truesize >=
1634 (unsigned)sk->sk_rcvbuf)
1635 goto drop_n_acct;
1636
1637 if (skb_shared(skb)) {
1638 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1639 if (nskb == NULL)
1640 goto drop_n_acct;
1641
1642 if (skb_head != skb->data) {
1643 skb->data = skb_head;
1644 skb->len = skb_len;
1645 }
1646 kfree_skb(skb);
1647 skb = nskb;
1648 }
1649
1650 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1651 sizeof(skb->cb));
1652
1653 sll = &PACKET_SKB_CB(skb)->sa.ll;
1654 sll->sll_family = AF_PACKET;
1655 sll->sll_hatype = dev->type;
1656 sll->sll_protocol = skb->protocol;
1657 sll->sll_pkttype = skb->pkt_type;
1658 if (unlikely(po->origdev))
1659 sll->sll_ifindex = orig_dev->ifindex;
1660 else
1661 sll->sll_ifindex = dev->ifindex;
1662
1663 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1664
1665 PACKET_SKB_CB(skb)->origlen = skb->len;
1666
1667 if (pskb_trim(skb, snaplen))
1668 goto drop_n_acct;
1669
1670 skb_set_owner_r(skb, sk);
1671 skb->dev = NULL;
1672 skb_dst_drop(skb);
1673
1674 /* drop conntrack reference */
1675 nf_reset(skb);
1676
1677 spin_lock(&sk->sk_receive_queue.lock);
1678 po->stats.tp_packets++;
1679 skb->dropcount = atomic_read(&sk->sk_drops);
1680 __skb_queue_tail(&sk->sk_receive_queue, skb);
1681 spin_unlock(&sk->sk_receive_queue.lock);
1682 sk->sk_data_ready(sk, skb->len);
1683 return 0;
1684
1685 drop_n_acct:
1686 spin_lock(&sk->sk_receive_queue.lock);
1687 po->stats.tp_drops++;
1688 atomic_inc(&sk->sk_drops);
1689 spin_unlock(&sk->sk_receive_queue.lock);
1690
1691 drop_n_restore:
1692 if (skb_head != skb->data && skb_shared(skb)) {
1693 skb->data = skb_head;
1694 skb->len = skb_len;
1695 }
1696 drop:
1697 consume_skb(skb);
1698 return 0;
1699 }
1700
1701 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1702 struct packet_type *pt, struct net_device *orig_dev)
1703 {
1704 struct sock *sk;
1705 struct packet_sock *po;
1706 struct sockaddr_ll *sll;
1707 union {
1708 struct tpacket_hdr *h1;
1709 struct tpacket2_hdr *h2;
1710 struct tpacket3_hdr *h3;
1711 void *raw;
1712 } h;
1713 u8 *skb_head = skb->data;
1714 int skb_len = skb->len;
1715 unsigned int snaplen, res;
1716 unsigned long status = TP_STATUS_USER;
1717 unsigned short macoff, netoff, hdrlen;
1718 struct sk_buff *copy_skb = NULL;
1719 struct timeval tv;
1720 struct timespec ts;
1721 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1722
1723 if (skb->pkt_type == PACKET_LOOPBACK)
1724 goto drop;
1725
1726 sk = pt->af_packet_priv;
1727 po = pkt_sk(sk);
1728
1729 if (!net_eq(dev_net(dev), sock_net(sk)))
1730 goto drop;
1731
1732 if (dev->header_ops) {
1733 if (sk->sk_type != SOCK_DGRAM)
1734 skb_push(skb, skb->data - skb_mac_header(skb));
1735 else if (skb->pkt_type == PACKET_OUTGOING) {
1736 /* Special case: outgoing packets have ll header at head */
1737 skb_pull(skb, skb_network_offset(skb));
1738 }
1739 }
1740
1741 if (skb->ip_summed == CHECKSUM_PARTIAL)
1742 status |= TP_STATUS_CSUMNOTREADY;
1743
1744 snaplen = skb->len;
1745
1746 res = run_filter(skb, sk, snaplen);
1747 if (!res)
1748 goto drop_n_restore;
1749 if (snaplen > res)
1750 snaplen = res;
1751
1752 if (sk->sk_type == SOCK_DGRAM) {
1753 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1754 po->tp_reserve;
1755 } else {
1756 unsigned maclen = skb_network_offset(skb);
1757 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1758 (maclen < 16 ? 16 : maclen)) +
1759 po->tp_reserve;
1760 macoff = netoff - maclen;
1761 }
1762 if (po->tp_version <= TPACKET_V2) {
1763 if (macoff + snaplen > po->rx_ring.frame_size) {
1764 if (po->copy_thresh &&
1765 atomic_read(&sk->sk_rmem_alloc) + skb->truesize
1766 < (unsigned)sk->sk_rcvbuf) {
1767 if (skb_shared(skb)) {
1768 copy_skb = skb_clone(skb, GFP_ATOMIC);
1769 } else {
1770 copy_skb = skb_get(skb);
1771 skb_head = skb->data;
1772 }
1773 if (copy_skb)
1774 skb_set_owner_r(copy_skb, sk);
1775 }
1776 snaplen = po->rx_ring.frame_size - macoff;
1777 if ((int)snaplen < 0)
1778 snaplen = 0;
1779 }
1780 }
1781 spin_lock(&sk->sk_receive_queue.lock);
1782 h.raw = packet_current_rx_frame(po, skb,
1783 TP_STATUS_KERNEL, (macoff+snaplen));
1784 if (!h.raw)
1785 goto ring_is_full;
1786 if (po->tp_version <= TPACKET_V2) {
1787 packet_increment_rx_head(po, &po->rx_ring);
1788 /*
1789 * LOSING will be reported till you read the stats,
1790 * because it's COR - Clear On Read.
1791 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1792 * at packet level.
1793 */
1794 if (po->stats.tp_drops)
1795 status |= TP_STATUS_LOSING;
1796 }
1797 po->stats.tp_packets++;
1798 if (copy_skb) {
1799 status |= TP_STATUS_COPY;
1800 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1801 }
1802 spin_unlock(&sk->sk_receive_queue.lock);
1803
1804 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1805
1806 switch (po->tp_version) {
1807 case TPACKET_V1:
1808 h.h1->tp_len = skb->len;
1809 h.h1->tp_snaplen = snaplen;
1810 h.h1->tp_mac = macoff;
1811 h.h1->tp_net = netoff;
1812 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1813 && shhwtstamps->syststamp.tv64)
1814 tv = ktime_to_timeval(shhwtstamps->syststamp);
1815 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1816 && shhwtstamps->hwtstamp.tv64)
1817 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1818 else if (skb->tstamp.tv64)
1819 tv = ktime_to_timeval(skb->tstamp);
1820 else
1821 do_gettimeofday(&tv);
1822 h.h1->tp_sec = tv.tv_sec;
1823 h.h1->tp_usec = tv.tv_usec;
1824 hdrlen = sizeof(*h.h1);
1825 break;
1826 case TPACKET_V2:
1827 h.h2->tp_len = skb->len;
1828 h.h2->tp_snaplen = snaplen;
1829 h.h2->tp_mac = macoff;
1830 h.h2->tp_net = netoff;
1831 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1832 && shhwtstamps->syststamp.tv64)
1833 ts = ktime_to_timespec(shhwtstamps->syststamp);
1834 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1835 && shhwtstamps->hwtstamp.tv64)
1836 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1837 else if (skb->tstamp.tv64)
1838 ts = ktime_to_timespec(skb->tstamp);
1839 else
1840 getnstimeofday(&ts);
1841 h.h2->tp_sec = ts.tv_sec;
1842 h.h2->tp_nsec = ts.tv_nsec;
1843 if (vlan_tx_tag_present(skb)) {
1844 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1845 status |= TP_STATUS_VLAN_VALID;
1846 } else {
1847 h.h2->tp_vlan_tci = 0;
1848 }
1849 h.h2->tp_padding = 0;
1850 hdrlen = sizeof(*h.h2);
1851 break;
1852 case TPACKET_V3:
1853 /* tp_nxt_offset,vlan are already populated above.
1854 * So DONT clear those fields here
1855 */
1856 h.h3->tp_status |= status;
1857 h.h3->tp_len = skb->len;
1858 h.h3->tp_snaplen = snaplen;
1859 h.h3->tp_mac = macoff;
1860 h.h3->tp_net = netoff;
1861 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1862 && shhwtstamps->syststamp.tv64)
1863 ts = ktime_to_timespec(shhwtstamps->syststamp);
1864 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1865 && shhwtstamps->hwtstamp.tv64)
1866 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1867 else if (skb->tstamp.tv64)
1868 ts = ktime_to_timespec(skb->tstamp);
1869 else
1870 getnstimeofday(&ts);
1871 h.h3->tp_sec = ts.tv_sec;
1872 h.h3->tp_nsec = ts.tv_nsec;
1873 hdrlen = sizeof(*h.h3);
1874 break;
1875 default:
1876 BUG();
1877 }
1878
1879 sll = h.raw + TPACKET_ALIGN(hdrlen);
1880 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1881 sll->sll_family = AF_PACKET;
1882 sll->sll_hatype = dev->type;
1883 sll->sll_protocol = skb->protocol;
1884 sll->sll_pkttype = skb->pkt_type;
1885 if (unlikely(po->origdev))
1886 sll->sll_ifindex = orig_dev->ifindex;
1887 else
1888 sll->sll_ifindex = dev->ifindex;
1889
1890 smp_mb();
1891 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1892 {
1893 u8 *start, *end;
1894
1895 if (po->tp_version <= TPACKET_V2) {
1896 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1897 + macoff + snaplen);
1898 for (start = h.raw; start < end; start += PAGE_SIZE)
1899 flush_dcache_page(pgv_to_page(start));
1900 }
1901 smp_wmb();
1902 }
1903 #endif
1904 if (po->tp_version <= TPACKET_V2)
1905 __packet_set_status(po, h.raw, status);
1906 else
1907 prb_clear_blk_fill_status(&po->rx_ring);
1908
1909 sk->sk_data_ready(sk, 0);
1910
1911 drop_n_restore:
1912 if (skb_head != skb->data && skb_shared(skb)) {
1913 skb->data = skb_head;
1914 skb->len = skb_len;
1915 }
1916 drop:
1917 kfree_skb(skb);
1918 return 0;
1919
1920 ring_is_full:
1921 po->stats.tp_drops++;
1922 spin_unlock(&sk->sk_receive_queue.lock);
1923
1924 sk->sk_data_ready(sk, 0);
1925 kfree_skb(copy_skb);
1926 goto drop_n_restore;
1927 }
1928
1929 static void tpacket_destruct_skb(struct sk_buff *skb)
1930 {
1931 struct packet_sock *po = pkt_sk(skb->sk);
1932 void *ph;
1933
1934 if (likely(po->tx_ring.pg_vec)) {
1935 ph = skb_shinfo(skb)->destructor_arg;
1936 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
1937 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1938 atomic_dec(&po->tx_ring.pending);
1939 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1940 }
1941
1942 sock_wfree(skb);
1943 }
1944
1945 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1946 void *frame, struct net_device *dev, int size_max,
1947 __be16 proto, unsigned char *addr)
1948 {
1949 union {
1950 struct tpacket_hdr *h1;
1951 struct tpacket2_hdr *h2;
1952 void *raw;
1953 } ph;
1954 int to_write, offset, len, tp_len, nr_frags, len_max;
1955 struct socket *sock = po->sk.sk_socket;
1956 struct page *page;
1957 void *data;
1958 int err;
1959
1960 ph.raw = frame;
1961
1962 skb->protocol = proto;
1963 skb->dev = dev;
1964 skb->priority = po->sk.sk_priority;
1965 skb->mark = po->sk.sk_mark;
1966 skb_shinfo(skb)->destructor_arg = ph.raw;
1967
1968 switch (po->tp_version) {
1969 case TPACKET_V2:
1970 tp_len = ph.h2->tp_len;
1971 break;
1972 default:
1973 tp_len = ph.h1->tp_len;
1974 break;
1975 }
1976 if (unlikely(tp_len > size_max)) {
1977 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1978 return -EMSGSIZE;
1979 }
1980
1981 skb_reserve(skb, LL_RESERVED_SPACE(dev));
1982 skb_reset_network_header(skb);
1983
1984 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1985 to_write = tp_len;
1986
1987 if (sock->type == SOCK_DGRAM) {
1988 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1989 NULL, tp_len);
1990 if (unlikely(err < 0))
1991 return -EINVAL;
1992 } else if (dev->hard_header_len) {
1993 /* net device doesn't like empty head */
1994 if (unlikely(tp_len <= dev->hard_header_len)) {
1995 pr_err("packet size is too short (%d < %d)\n",
1996 tp_len, dev->hard_header_len);
1997 return -EINVAL;
1998 }
1999
2000 skb_push(skb, dev->hard_header_len);
2001 err = skb_store_bits(skb, 0, data,
2002 dev->hard_header_len);
2003 if (unlikely(err))
2004 return err;
2005
2006 data += dev->hard_header_len;
2007 to_write -= dev->hard_header_len;
2008 }
2009
2010 err = -EFAULT;
2011 offset = offset_in_page(data);
2012 len_max = PAGE_SIZE - offset;
2013 len = ((to_write > len_max) ? len_max : to_write);
2014
2015 skb->data_len = to_write;
2016 skb->len += to_write;
2017 skb->truesize += to_write;
2018 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2019
2020 while (likely(to_write)) {
2021 nr_frags = skb_shinfo(skb)->nr_frags;
2022
2023 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2024 pr_err("Packet exceed the number of skb frags(%lu)\n",
2025 MAX_SKB_FRAGS);
2026 return -EFAULT;
2027 }
2028
2029 page = pgv_to_page(data);
2030 data += len;
2031 flush_dcache_page(page);
2032 get_page(page);
2033 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2034 to_write -= len;
2035 offset = 0;
2036 len_max = PAGE_SIZE;
2037 len = ((to_write > len_max) ? len_max : to_write);
2038 }
2039
2040 return tp_len;
2041 }
2042
2043 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2044 {
2045 struct sk_buff *skb;
2046 struct net_device *dev;
2047 __be16 proto;
2048 bool need_rls_dev = false;
2049 int err, reserve = 0;
2050 void *ph;
2051 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2052 int tp_len, size_max;
2053 unsigned char *addr;
2054 int len_sum = 0;
2055 int status = 0;
2056
2057 mutex_lock(&po->pg_vec_lock);
2058
2059 err = -EBUSY;
2060 if (saddr == NULL) {
2061 dev = po->prot_hook.dev;
2062 proto = po->num;
2063 addr = NULL;
2064 } else {
2065 err = -EINVAL;
2066 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2067 goto out;
2068 if (msg->msg_namelen < (saddr->sll_halen
2069 + offsetof(struct sockaddr_ll,
2070 sll_addr)))
2071 goto out;
2072 proto = saddr->sll_protocol;
2073 addr = saddr->sll_addr;
2074 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2075 need_rls_dev = true;
2076 }
2077
2078 err = -ENXIO;
2079 if (unlikely(dev == NULL))
2080 goto out;
2081
2082 reserve = dev->hard_header_len;
2083
2084 err = -ENETDOWN;
2085 if (unlikely(!(dev->flags & IFF_UP)))
2086 goto out_put;
2087
2088 size_max = po->tx_ring.frame_size
2089 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2090
2091 if (size_max > dev->mtu + reserve)
2092 size_max = dev->mtu + reserve;
2093
2094 do {
2095 ph = packet_current_frame(po, &po->tx_ring,
2096 TP_STATUS_SEND_REQUEST);
2097
2098 if (unlikely(ph == NULL)) {
2099 schedule();
2100 continue;
2101 }
2102
2103 status = TP_STATUS_SEND_REQUEST;
2104 skb = sock_alloc_send_skb(&po->sk,
2105 LL_ALLOCATED_SPACE(dev)
2106 + sizeof(struct sockaddr_ll),
2107 0, &err);
2108
2109 if (unlikely(skb == NULL))
2110 goto out_status;
2111
2112 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2113 addr);
2114
2115 if (unlikely(tp_len < 0)) {
2116 if (po->tp_loss) {
2117 __packet_set_status(po, ph,
2118 TP_STATUS_AVAILABLE);
2119 packet_increment_head(&po->tx_ring);
2120 kfree_skb(skb);
2121 continue;
2122 } else {
2123 status = TP_STATUS_WRONG_FORMAT;
2124 err = tp_len;
2125 goto out_status;
2126 }
2127 }
2128
2129 skb->destructor = tpacket_destruct_skb;
2130 __packet_set_status(po, ph, TP_STATUS_SENDING);
2131 atomic_inc(&po->tx_ring.pending);
2132
2133 status = TP_STATUS_SEND_REQUEST;
2134 err = dev_queue_xmit(skb);
2135 if (unlikely(err > 0)) {
2136 err = net_xmit_errno(err);
2137 if (err && __packet_get_status(po, ph) ==
2138 TP_STATUS_AVAILABLE) {
2139 /* skb was destructed already */
2140 skb = NULL;
2141 goto out_status;
2142 }
2143 /*
2144 * skb was dropped but not destructed yet;
2145 * let's treat it like congestion or err < 0
2146 */
2147 err = 0;
2148 }
2149 packet_increment_head(&po->tx_ring);
2150 len_sum += tp_len;
2151 } while (likely((ph != NULL) ||
2152 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2153 (atomic_read(&po->tx_ring.pending))))
2154 );
2155
2156 err = len_sum;
2157 goto out_put;
2158
2159 out_status:
2160 __packet_set_status(po, ph, status);
2161 kfree_skb(skb);
2162 out_put:
2163 if (need_rls_dev)
2164 dev_put(dev);
2165 out:
2166 mutex_unlock(&po->pg_vec_lock);
2167 return err;
2168 }
2169
2170 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2171 size_t reserve, size_t len,
2172 size_t linear, int noblock,
2173 int *err)
2174 {
2175 struct sk_buff *skb;
2176
2177 /* Under a page? Don't bother with paged skb. */
2178 if (prepad + len < PAGE_SIZE || !linear)
2179 linear = len;
2180
2181 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2182 err);
2183 if (!skb)
2184 return NULL;
2185
2186 skb_reserve(skb, reserve);
2187 skb_put(skb, linear);
2188 skb->data_len = len - linear;
2189 skb->len += len - linear;
2190
2191 return skb;
2192 }
2193
2194 static int packet_snd(struct socket *sock,
2195 struct msghdr *msg, size_t len)
2196 {
2197 struct sock *sk = sock->sk;
2198 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2199 struct sk_buff *skb;
2200 struct net_device *dev;
2201 __be16 proto;
2202 bool need_rls_dev = false;
2203 unsigned char *addr;
2204 int err, reserve = 0;
2205 struct virtio_net_hdr vnet_hdr = { 0 };
2206 int offset = 0;
2207 int vnet_hdr_len;
2208 struct packet_sock *po = pkt_sk(sk);
2209 unsigned short gso_type = 0;
2210
2211 /*
2212 * Get and verify the address.
2213 */
2214
2215 if (saddr == NULL) {
2216 dev = po->prot_hook.dev;
2217 proto = po->num;
2218 addr = NULL;
2219 } else {
2220 err = -EINVAL;
2221 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2222 goto out;
2223 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2224 goto out;
2225 proto = saddr->sll_protocol;
2226 addr = saddr->sll_addr;
2227 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2228 need_rls_dev = true;
2229 }
2230
2231 err = -ENXIO;
2232 if (dev == NULL)
2233 goto out_unlock;
2234 if (sock->type == SOCK_RAW)
2235 reserve = dev->hard_header_len;
2236
2237 err = -ENETDOWN;
2238 if (!(dev->flags & IFF_UP))
2239 goto out_unlock;
2240
2241 if (po->has_vnet_hdr) {
2242 vnet_hdr_len = sizeof(vnet_hdr);
2243
2244 err = -EINVAL;
2245 if (len < vnet_hdr_len)
2246 goto out_unlock;
2247
2248 len -= vnet_hdr_len;
2249
2250 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2251 vnet_hdr_len);
2252 if (err < 0)
2253 goto out_unlock;
2254
2255 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2256 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2257 vnet_hdr.hdr_len))
2258 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2259 vnet_hdr.csum_offset + 2;
2260
2261 err = -EINVAL;
2262 if (vnet_hdr.hdr_len > len)
2263 goto out_unlock;
2264
2265 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2266 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2267 case VIRTIO_NET_HDR_GSO_TCPV4:
2268 gso_type = SKB_GSO_TCPV4;
2269 break;
2270 case VIRTIO_NET_HDR_GSO_TCPV6:
2271 gso_type = SKB_GSO_TCPV6;
2272 break;
2273 case VIRTIO_NET_HDR_GSO_UDP:
2274 gso_type = SKB_GSO_UDP;
2275 break;
2276 default:
2277 goto out_unlock;
2278 }
2279
2280 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2281 gso_type |= SKB_GSO_TCP_ECN;
2282
2283 if (vnet_hdr.gso_size == 0)
2284 goto out_unlock;
2285
2286 }
2287 }
2288
2289 err = -EMSGSIZE;
2290 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
2291 goto out_unlock;
2292
2293 err = -ENOBUFS;
2294 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
2295 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
2296 msg->msg_flags & MSG_DONTWAIT, &err);
2297 if (skb == NULL)
2298 goto out_unlock;
2299
2300 skb_set_network_header(skb, reserve);
2301
2302 err = -EINVAL;
2303 if (sock->type == SOCK_DGRAM &&
2304 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2305 goto out_free;
2306
2307 /* Returns -EFAULT on error */
2308 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2309 if (err)
2310 goto out_free;
2311 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2312 if (err < 0)
2313 goto out_free;
2314
2315 if (!gso_type && (len > dev->mtu + reserve)) {
2316 /* Earlier code assumed this would be a VLAN pkt,
2317 * double-check this now that we have the actual
2318 * packet in hand.
2319 */
2320 struct ethhdr *ehdr;
2321 skb_reset_mac_header(skb);
2322 ehdr = eth_hdr(skb);
2323 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2324 err = -EMSGSIZE;
2325 goto out_free;
2326 }
2327 }
2328
2329 skb->protocol = proto;
2330 skb->dev = dev;
2331 skb->priority = sk->sk_priority;
2332 skb->mark = sk->sk_mark;
2333
2334 if (po->has_vnet_hdr) {
2335 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2336 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2337 vnet_hdr.csum_offset)) {
2338 err = -EINVAL;
2339 goto out_free;
2340 }
2341 }
2342
2343 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2344 skb_shinfo(skb)->gso_type = gso_type;
2345
2346 /* Header must be checked, and gso_segs computed. */
2347 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2348 skb_shinfo(skb)->gso_segs = 0;
2349
2350 len += vnet_hdr_len;
2351 }
2352
2353 /*
2354 * Now send it
2355 */
2356
2357 err = dev_queue_xmit(skb);
2358 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2359 goto out_unlock;
2360
2361 if (need_rls_dev)
2362 dev_put(dev);
2363
2364 return len;
2365
2366 out_free:
2367 kfree_skb(skb);
2368 out_unlock:
2369 if (dev && need_rls_dev)
2370 dev_put(dev);
2371 out:
2372 return err;
2373 }
2374
2375 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2376 struct msghdr *msg, size_t len)
2377 {
2378 struct sock *sk = sock->sk;
2379 struct packet_sock *po = pkt_sk(sk);
2380 if (po->tx_ring.pg_vec)
2381 return tpacket_snd(po, msg);
2382 else
2383 return packet_snd(sock, msg, len);
2384 }
2385
2386 /*
2387 * Close a PACKET socket. This is fairly simple. We immediately go
2388 * to 'closed' state and remove our protocol entry in the device list.
2389 */
2390
2391 static int packet_release(struct socket *sock)
2392 {
2393 struct sock *sk = sock->sk;
2394 struct packet_sock *po;
2395 struct net *net;
2396 union tpacket_req_u req_u;
2397
2398 if (!sk)
2399 return 0;
2400
2401 net = sock_net(sk);
2402 po = pkt_sk(sk);
2403
2404 spin_lock_bh(&net->packet.sklist_lock);
2405 sk_del_node_init_rcu(sk);
2406 sock_prot_inuse_add(net, sk->sk_prot, -1);
2407 spin_unlock_bh(&net->packet.sklist_lock);
2408
2409 spin_lock(&po->bind_lock);
2410 unregister_prot_hook(sk, false);
2411 if (po->prot_hook.dev) {
2412 dev_put(po->prot_hook.dev);
2413 po->prot_hook.dev = NULL;
2414 }
2415 spin_unlock(&po->bind_lock);
2416
2417 packet_flush_mclist(sk);
2418
2419 memset(&req_u, 0, sizeof(req_u));
2420
2421 if (po->rx_ring.pg_vec)
2422 packet_set_ring(sk, &req_u, 1, 0);
2423
2424 if (po->tx_ring.pg_vec)
2425 packet_set_ring(sk, &req_u, 1, 1);
2426
2427 fanout_release(sk);
2428
2429 synchronize_net();
2430 /*
2431 * Now the socket is dead. No more input will appear.
2432 */
2433 sock_orphan(sk);
2434 sock->sk = NULL;
2435
2436 /* Purge queues */
2437
2438 skb_queue_purge(&sk->sk_receive_queue);
2439 sk_refcnt_debug_release(sk);
2440
2441 sock_put(sk);
2442 return 0;
2443 }
2444
2445 /*
2446 * Attach a packet hook.
2447 */
2448
2449 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2450 {
2451 struct packet_sock *po = pkt_sk(sk);
2452
2453 if (po->fanout)
2454 return -EINVAL;
2455
2456 lock_sock(sk);
2457
2458 spin_lock(&po->bind_lock);
2459 unregister_prot_hook(sk, true);
2460 po->num = protocol;
2461 po->prot_hook.type = protocol;
2462 if (po->prot_hook.dev)
2463 dev_put(po->prot_hook.dev);
2464 po->prot_hook.dev = dev;
2465
2466 po->ifindex = dev ? dev->ifindex : 0;
2467
2468 if (protocol == 0)
2469 goto out_unlock;
2470
2471 if (!dev || (dev->flags & IFF_UP)) {
2472 register_prot_hook(sk);
2473 } else {
2474 sk->sk_err = ENETDOWN;
2475 if (!sock_flag(sk, SOCK_DEAD))
2476 sk->sk_error_report(sk);
2477 }
2478
2479 out_unlock:
2480 spin_unlock(&po->bind_lock);
2481 release_sock(sk);
2482 return 0;
2483 }
2484
2485 /*
2486 * Bind a packet socket to a device
2487 */
2488
2489 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2490 int addr_len)
2491 {
2492 struct sock *sk = sock->sk;
2493 char name[15];
2494 struct net_device *dev;
2495 int err = -ENODEV;
2496
2497 /*
2498 * Check legality
2499 */
2500
2501 if (addr_len != sizeof(struct sockaddr))
2502 return -EINVAL;
2503 strlcpy(name, uaddr->sa_data, sizeof(name));
2504
2505 dev = dev_get_by_name(sock_net(sk), name);
2506 if (dev)
2507 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2508 return err;
2509 }
2510
2511 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2512 {
2513 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2514 struct sock *sk = sock->sk;
2515 struct net_device *dev = NULL;
2516 int err;
2517
2518
2519 /*
2520 * Check legality
2521 */
2522
2523 if (addr_len < sizeof(struct sockaddr_ll))
2524 return -EINVAL;
2525 if (sll->sll_family != AF_PACKET)
2526 return -EINVAL;
2527
2528 if (sll->sll_ifindex) {
2529 err = -ENODEV;
2530 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2531 if (dev == NULL)
2532 goto out;
2533 }
2534 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2535
2536 out:
2537 return err;
2538 }
2539
2540 static struct proto packet_proto = {
2541 .name = "PACKET",
2542 .owner = THIS_MODULE,
2543 .obj_size = sizeof(struct packet_sock),
2544 };
2545
2546 /*
2547 * Create a packet of type SOCK_PACKET.
2548 */
2549
2550 static int packet_create(struct net *net, struct socket *sock, int protocol,
2551 int kern)
2552 {
2553 struct sock *sk;
2554 struct packet_sock *po;
2555 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2556 int err;
2557
2558 if (!capable(CAP_NET_RAW))
2559 return -EPERM;
2560 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2561 sock->type != SOCK_PACKET)
2562 return -ESOCKTNOSUPPORT;
2563
2564 sock->state = SS_UNCONNECTED;
2565
2566 err = -ENOBUFS;
2567 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2568 if (sk == NULL)
2569 goto out;
2570
2571 sock->ops = &packet_ops;
2572 if (sock->type == SOCK_PACKET)
2573 sock->ops = &packet_ops_spkt;
2574
2575 sock_init_data(sock, sk);
2576
2577 po = pkt_sk(sk);
2578 sk->sk_family = PF_PACKET;
2579 po->num = proto;
2580
2581 sk->sk_destruct = packet_sock_destruct;
2582 sk_refcnt_debug_inc(sk);
2583
2584 /*
2585 * Attach a protocol block
2586 */
2587
2588 spin_lock_init(&po->bind_lock);
2589 mutex_init(&po->pg_vec_lock);
2590 po->prot_hook.func = packet_rcv;
2591
2592 if (sock->type == SOCK_PACKET)
2593 po->prot_hook.func = packet_rcv_spkt;
2594
2595 po->prot_hook.af_packet_priv = sk;
2596
2597 if (proto) {
2598 po->prot_hook.type = proto;
2599 register_prot_hook(sk);
2600 }
2601
2602 spin_lock_bh(&net->packet.sklist_lock);
2603 sk_add_node_rcu(sk, &net->packet.sklist);
2604 sock_prot_inuse_add(net, &packet_proto, 1);
2605 spin_unlock_bh(&net->packet.sklist_lock);
2606
2607 return 0;
2608 out:
2609 return err;
2610 }
2611
2612 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2613 {
2614 struct sock_exterr_skb *serr;
2615 struct sk_buff *skb, *skb2;
2616 int copied, err;
2617
2618 err = -EAGAIN;
2619 skb = skb_dequeue(&sk->sk_error_queue);
2620 if (skb == NULL)
2621 goto out;
2622
2623 copied = skb->len;
2624 if (copied > len) {
2625 msg->msg_flags |= MSG_TRUNC;
2626 copied = len;
2627 }
2628 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2629 if (err)
2630 goto out_free_skb;
2631
2632 sock_recv_timestamp(msg, sk, skb);
2633
2634 serr = SKB_EXT_ERR(skb);
2635 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2636 sizeof(serr->ee), &serr->ee);
2637
2638 msg->msg_flags |= MSG_ERRQUEUE;
2639 err = copied;
2640
2641 /* Reset and regenerate socket error */
2642 spin_lock_bh(&sk->sk_error_queue.lock);
2643 sk->sk_err = 0;
2644 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2645 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2646 spin_unlock_bh(&sk->sk_error_queue.lock);
2647 sk->sk_error_report(sk);
2648 } else
2649 spin_unlock_bh(&sk->sk_error_queue.lock);
2650
2651 out_free_skb:
2652 kfree_skb(skb);
2653 out:
2654 return err;
2655 }
2656
2657 /*
2658 * Pull a packet from our receive queue and hand it to the user.
2659 * If necessary we block.
2660 */
2661
2662 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2663 struct msghdr *msg, size_t len, int flags)
2664 {
2665 struct sock *sk = sock->sk;
2666 struct sk_buff *skb;
2667 int copied, err;
2668 struct sockaddr_ll *sll;
2669 int vnet_hdr_len = 0;
2670
2671 err = -EINVAL;
2672 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2673 goto out;
2674
2675 #if 0
2676 /* What error should we return now? EUNATTACH? */
2677 if (pkt_sk(sk)->ifindex < 0)
2678 return -ENODEV;
2679 #endif
2680
2681 if (flags & MSG_ERRQUEUE) {
2682 err = packet_recv_error(sk, msg, len);
2683 goto out;
2684 }
2685
2686 /*
2687 * Call the generic datagram receiver. This handles all sorts
2688 * of horrible races and re-entrancy so we can forget about it
2689 * in the protocol layers.
2690 *
2691 * Now it will return ENETDOWN, if device have just gone down,
2692 * but then it will block.
2693 */
2694
2695 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2696
2697 /*
2698 * An error occurred so return it. Because skb_recv_datagram()
2699 * handles the blocking we don't see and worry about blocking
2700 * retries.
2701 */
2702
2703 if (skb == NULL)
2704 goto out;
2705
2706 if (pkt_sk(sk)->has_vnet_hdr) {
2707 struct virtio_net_hdr vnet_hdr = { 0 };
2708
2709 err = -EINVAL;
2710 vnet_hdr_len = sizeof(vnet_hdr);
2711 if (len < vnet_hdr_len)
2712 goto out_free;
2713
2714 len -= vnet_hdr_len;
2715
2716 if (skb_is_gso(skb)) {
2717 struct skb_shared_info *sinfo = skb_shinfo(skb);
2718
2719 /* This is a hint as to how much should be linear. */
2720 vnet_hdr.hdr_len = skb_headlen(skb);
2721 vnet_hdr.gso_size = sinfo->gso_size;
2722 if (sinfo->gso_type & SKB_GSO_TCPV4)
2723 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2724 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2725 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2726 else if (sinfo->gso_type & SKB_GSO_UDP)
2727 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2728 else if (sinfo->gso_type & SKB_GSO_FCOE)
2729 goto out_free;
2730 else
2731 BUG();
2732 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2733 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2734 } else
2735 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2736
2737 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2738 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2739 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2740 vnet_hdr.csum_offset = skb->csum_offset;
2741 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2742 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2743 } /* else everything is zero */
2744
2745 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2746 vnet_hdr_len);
2747 if (err < 0)
2748 goto out_free;
2749 }
2750
2751 /*
2752 * If the address length field is there to be filled in, we fill
2753 * it in now.
2754 */
2755
2756 sll = &PACKET_SKB_CB(skb)->sa.ll;
2757 if (sock->type == SOCK_PACKET)
2758 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2759 else
2760 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2761
2762 /*
2763 * You lose any data beyond the buffer you gave. If it worries a
2764 * user program they can ask the device for its MTU anyway.
2765 */
2766
2767 copied = skb->len;
2768 if (copied > len) {
2769 copied = len;
2770 msg->msg_flags |= MSG_TRUNC;
2771 }
2772
2773 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2774 if (err)
2775 goto out_free;
2776
2777 sock_recv_ts_and_drops(msg, sk, skb);
2778
2779 if (msg->msg_name)
2780 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2781 msg->msg_namelen);
2782
2783 if (pkt_sk(sk)->auxdata) {
2784 struct tpacket_auxdata aux;
2785
2786 aux.tp_status = TP_STATUS_USER;
2787 if (skb->ip_summed == CHECKSUM_PARTIAL)
2788 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2789 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2790 aux.tp_snaplen = skb->len;
2791 aux.tp_mac = 0;
2792 aux.tp_net = skb_network_offset(skb);
2793 if (vlan_tx_tag_present(skb)) {
2794 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2795 aux.tp_status |= TP_STATUS_VLAN_VALID;
2796 } else {
2797 aux.tp_vlan_tci = 0;
2798 }
2799 aux.tp_padding = 0;
2800 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2801 }
2802
2803 /*
2804 * Free or return the buffer as appropriate. Again this
2805 * hides all the races and re-entrancy issues from us.
2806 */
2807 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2808
2809 out_free:
2810 skb_free_datagram(sk, skb);
2811 out:
2812 return err;
2813 }
2814
2815 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2816 int *uaddr_len, int peer)
2817 {
2818 struct net_device *dev;
2819 struct sock *sk = sock->sk;
2820
2821 if (peer)
2822 return -EOPNOTSUPP;
2823
2824 uaddr->sa_family = AF_PACKET;
2825 rcu_read_lock();
2826 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2827 if (dev)
2828 strncpy(uaddr->sa_data, dev->name, 14);
2829 else
2830 memset(uaddr->sa_data, 0, 14);
2831 rcu_read_unlock();
2832 *uaddr_len = sizeof(*uaddr);
2833
2834 return 0;
2835 }
2836
2837 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2838 int *uaddr_len, int peer)
2839 {
2840 struct net_device *dev;
2841 struct sock *sk = sock->sk;
2842 struct packet_sock *po = pkt_sk(sk);
2843 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2844
2845 if (peer)
2846 return -EOPNOTSUPP;
2847
2848 sll->sll_family = AF_PACKET;
2849 sll->sll_ifindex = po->ifindex;
2850 sll->sll_protocol = po->num;
2851 sll->sll_pkttype = 0;
2852 rcu_read_lock();
2853 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2854 if (dev) {
2855 sll->sll_hatype = dev->type;
2856 sll->sll_halen = dev->addr_len;
2857 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2858 } else {
2859 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2860 sll->sll_halen = 0;
2861 }
2862 rcu_read_unlock();
2863 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2864
2865 return 0;
2866 }
2867
2868 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2869 int what)
2870 {
2871 switch (i->type) {
2872 case PACKET_MR_MULTICAST:
2873 if (i->alen != dev->addr_len)
2874 return -EINVAL;
2875 if (what > 0)
2876 return dev_mc_add(dev, i->addr);
2877 else
2878 return dev_mc_del(dev, i->addr);
2879 break;
2880 case PACKET_MR_PROMISC:
2881 return dev_set_promiscuity(dev, what);
2882 break;
2883 case PACKET_MR_ALLMULTI:
2884 return dev_set_allmulti(dev, what);
2885 break;
2886 case PACKET_MR_UNICAST:
2887 if (i->alen != dev->addr_len)
2888 return -EINVAL;
2889 if (what > 0)
2890 return dev_uc_add(dev, i->addr);
2891 else
2892 return dev_uc_del(dev, i->addr);
2893 break;
2894 default:
2895 break;
2896 }
2897 return 0;
2898 }
2899
2900 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2901 {
2902 for ( ; i; i = i->next) {
2903 if (i->ifindex == dev->ifindex)
2904 packet_dev_mc(dev, i, what);
2905 }
2906 }
2907
2908 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2909 {
2910 struct packet_sock *po = pkt_sk(sk);
2911 struct packet_mclist *ml, *i;
2912 struct net_device *dev;
2913 int err;
2914
2915 rtnl_lock();
2916
2917 err = -ENODEV;
2918 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2919 if (!dev)
2920 goto done;
2921
2922 err = -EINVAL;
2923 if (mreq->mr_alen > dev->addr_len)
2924 goto done;
2925
2926 err = -ENOBUFS;
2927 i = kmalloc(sizeof(*i), GFP_KERNEL);
2928 if (i == NULL)
2929 goto done;
2930
2931 err = 0;
2932 for (ml = po->mclist; ml; ml = ml->next) {
2933 if (ml->ifindex == mreq->mr_ifindex &&
2934 ml->type == mreq->mr_type &&
2935 ml->alen == mreq->mr_alen &&
2936 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2937 ml->count++;
2938 /* Free the new element ... */
2939 kfree(i);
2940 goto done;
2941 }
2942 }
2943
2944 i->type = mreq->mr_type;
2945 i->ifindex = mreq->mr_ifindex;
2946 i->alen = mreq->mr_alen;
2947 memcpy(i->addr, mreq->mr_address, i->alen);
2948 i->count = 1;
2949 i->next = po->mclist;
2950 po->mclist = i;
2951 err = packet_dev_mc(dev, i, 1);
2952 if (err) {
2953 po->mclist = i->next;
2954 kfree(i);
2955 }
2956
2957 done:
2958 rtnl_unlock();
2959 return err;
2960 }
2961
2962 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2963 {
2964 struct packet_mclist *ml, **mlp;
2965
2966 rtnl_lock();
2967
2968 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2969 if (ml->ifindex == mreq->mr_ifindex &&
2970 ml->type == mreq->mr_type &&
2971 ml->alen == mreq->mr_alen &&
2972 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2973 if (--ml->count == 0) {
2974 struct net_device *dev;
2975 *mlp = ml->next;
2976 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2977 if (dev)
2978 packet_dev_mc(dev, ml, -1);
2979 kfree(ml);
2980 }
2981 rtnl_unlock();
2982 return 0;
2983 }
2984 }
2985 rtnl_unlock();
2986 return -EADDRNOTAVAIL;
2987 }
2988
2989 static void packet_flush_mclist(struct sock *sk)
2990 {
2991 struct packet_sock *po = pkt_sk(sk);
2992 struct packet_mclist *ml;
2993
2994 if (!po->mclist)
2995 return;
2996
2997 rtnl_lock();
2998 while ((ml = po->mclist) != NULL) {
2999 struct net_device *dev;
3000
3001 po->mclist = ml->next;
3002 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3003 if (dev != NULL)
3004 packet_dev_mc(dev, ml, -1);
3005 kfree(ml);
3006 }
3007 rtnl_unlock();
3008 }
3009
3010 static int
3011 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3012 {
3013 struct sock *sk = sock->sk;
3014 struct packet_sock *po = pkt_sk(sk);
3015 int ret;
3016
3017 if (level != SOL_PACKET)
3018 return -ENOPROTOOPT;
3019
3020 switch (optname) {
3021 case PACKET_ADD_MEMBERSHIP:
3022 case PACKET_DROP_MEMBERSHIP:
3023 {
3024 struct packet_mreq_max mreq;
3025 int len = optlen;
3026 memset(&mreq, 0, sizeof(mreq));
3027 if (len < sizeof(struct packet_mreq))
3028 return -EINVAL;
3029 if (len > sizeof(mreq))
3030 len = sizeof(mreq);
3031 if (copy_from_user(&mreq, optval, len))
3032 return -EFAULT;
3033 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3034 return -EINVAL;
3035 if (optname == PACKET_ADD_MEMBERSHIP)
3036 ret = packet_mc_add(sk, &mreq);
3037 else
3038 ret = packet_mc_drop(sk, &mreq);
3039 return ret;
3040 }
3041
3042 case PACKET_RX_RING:
3043 case PACKET_TX_RING:
3044 {
3045 union tpacket_req_u req_u;
3046 int len;
3047
3048 switch (po->tp_version) {
3049 case TPACKET_V1:
3050 case TPACKET_V2:
3051 len = sizeof(req_u.req);
3052 break;
3053 case TPACKET_V3:
3054 default:
3055 len = sizeof(req_u.req3);
3056 break;
3057 }
3058 if (optlen < len)
3059 return -EINVAL;
3060 if (pkt_sk(sk)->has_vnet_hdr)
3061 return -EINVAL;
3062 if (copy_from_user(&req_u.req, optval, len))
3063 return -EFAULT;
3064 return packet_set_ring(sk, &req_u, 0,
3065 optname == PACKET_TX_RING);
3066 }
3067 case PACKET_COPY_THRESH:
3068 {
3069 int val;
3070
3071 if (optlen != sizeof(val))
3072 return -EINVAL;
3073 if (copy_from_user(&val, optval, sizeof(val)))
3074 return -EFAULT;
3075
3076 pkt_sk(sk)->copy_thresh = val;
3077 return 0;
3078 }
3079 case PACKET_VERSION:
3080 {
3081 int val;
3082
3083 if (optlen != sizeof(val))
3084 return -EINVAL;
3085 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3086 return -EBUSY;
3087 if (copy_from_user(&val, optval, sizeof(val)))
3088 return -EFAULT;
3089 switch (val) {
3090 case TPACKET_V1:
3091 case TPACKET_V2:
3092 case TPACKET_V3:
3093 po->tp_version = val;
3094 return 0;
3095 default:
3096 return -EINVAL;
3097 }
3098 }
3099 case PACKET_RESERVE:
3100 {
3101 unsigned int val;
3102
3103 if (optlen != sizeof(val))
3104 return -EINVAL;
3105 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3106 return -EBUSY;
3107 if (copy_from_user(&val, optval, sizeof(val)))
3108 return -EFAULT;
3109 po->tp_reserve = val;
3110 return 0;
3111 }
3112 case PACKET_LOSS:
3113 {
3114 unsigned int val;
3115
3116 if (optlen != sizeof(val))
3117 return -EINVAL;
3118 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3119 return -EBUSY;
3120 if (copy_from_user(&val, optval, sizeof(val)))
3121 return -EFAULT;
3122 po->tp_loss = !!val;
3123 return 0;
3124 }
3125 case PACKET_AUXDATA:
3126 {
3127 int val;
3128
3129 if (optlen < sizeof(val))
3130 return -EINVAL;
3131 if (copy_from_user(&val, optval, sizeof(val)))
3132 return -EFAULT;
3133
3134 po->auxdata = !!val;
3135 return 0;
3136 }
3137 case PACKET_ORIGDEV:
3138 {
3139 int val;
3140
3141 if (optlen < sizeof(val))
3142 return -EINVAL;
3143 if (copy_from_user(&val, optval, sizeof(val)))
3144 return -EFAULT;
3145
3146 po->origdev = !!val;
3147 return 0;
3148 }
3149 case PACKET_VNET_HDR:
3150 {
3151 int val;
3152
3153 if (sock->type != SOCK_RAW)
3154 return -EINVAL;
3155 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3156 return -EBUSY;
3157 if (optlen < sizeof(val))
3158 return -EINVAL;
3159 if (copy_from_user(&val, optval, sizeof(val)))
3160 return -EFAULT;
3161
3162 po->has_vnet_hdr = !!val;
3163 return 0;
3164 }
3165 case PACKET_TIMESTAMP:
3166 {
3167 int val;
3168
3169 if (optlen != sizeof(val))
3170 return -EINVAL;
3171 if (copy_from_user(&val, optval, sizeof(val)))
3172 return -EFAULT;
3173
3174 po->tp_tstamp = val;
3175 return 0;
3176 }
3177 case PACKET_FANOUT:
3178 {
3179 int val;
3180
3181 if (optlen != sizeof(val))
3182 return -EINVAL;
3183 if (copy_from_user(&val, optval, sizeof(val)))
3184 return -EFAULT;
3185
3186 return fanout_add(sk, val & 0xffff, val >> 16);
3187 }
3188 default:
3189 return -ENOPROTOOPT;
3190 }
3191 }
3192
3193 static int packet_getsockopt(struct socket *sock, int level, int optname,
3194 char __user *optval, int __user *optlen)
3195 {
3196 int len;
3197 int val;
3198 struct sock *sk = sock->sk;
3199 struct packet_sock *po = pkt_sk(sk);
3200 void *data;
3201 struct tpacket_stats st;
3202 union tpacket_stats_u st_u;
3203
3204 if (level != SOL_PACKET)
3205 return -ENOPROTOOPT;
3206
3207 if (get_user(len, optlen))
3208 return -EFAULT;
3209
3210 if (len < 0)
3211 return -EINVAL;
3212
3213 switch (optname) {
3214 case PACKET_STATISTICS:
3215 if (po->tp_version == TPACKET_V3) {
3216 len = sizeof(struct tpacket_stats_v3);
3217 } else {
3218 if (len > sizeof(struct tpacket_stats))
3219 len = sizeof(struct tpacket_stats);
3220 }
3221 spin_lock_bh(&sk->sk_receive_queue.lock);
3222 if (po->tp_version == TPACKET_V3) {
3223 memcpy(&st_u.stats3, &po->stats,
3224 sizeof(struct tpacket_stats));
3225 st_u.stats3.tp_freeze_q_cnt =
3226 po->stats_u.stats3.tp_freeze_q_cnt;
3227 st_u.stats3.tp_packets += po->stats.tp_drops;
3228 data = &st_u.stats3;
3229 } else {
3230 st = po->stats;
3231 st.tp_packets += st.tp_drops;
3232 data = &st;
3233 }
3234 memset(&po->stats, 0, sizeof(st));
3235 spin_unlock_bh(&sk->sk_receive_queue.lock);
3236 break;
3237 case PACKET_AUXDATA:
3238 if (len > sizeof(int))
3239 len = sizeof(int);
3240 val = po->auxdata;
3241
3242 data = &val;
3243 break;
3244 case PACKET_ORIGDEV:
3245 if (len > sizeof(int))
3246 len = sizeof(int);
3247 val = po->origdev;
3248
3249 data = &val;
3250 break;
3251 case PACKET_VNET_HDR:
3252 if (len > sizeof(int))
3253 len = sizeof(int);
3254 val = po->has_vnet_hdr;
3255
3256 data = &val;
3257 break;
3258 case PACKET_VERSION:
3259 if (len > sizeof(int))
3260 len = sizeof(int);
3261 val = po->tp_version;
3262 data = &val;
3263 break;
3264 case PACKET_HDRLEN:
3265 if (len > sizeof(int))
3266 len = sizeof(int);
3267 if (copy_from_user(&val, optval, len))
3268 return -EFAULT;
3269 switch (val) {
3270 case TPACKET_V1:
3271 val = sizeof(struct tpacket_hdr);
3272 break;
3273 case TPACKET_V2:
3274 val = sizeof(struct tpacket2_hdr);
3275 break;
3276 case TPACKET_V3:
3277 val = sizeof(struct tpacket3_hdr);
3278 break;
3279 default:
3280 return -EINVAL;
3281 }
3282 data = &val;
3283 break;
3284 case PACKET_RESERVE:
3285 if (len > sizeof(unsigned int))
3286 len = sizeof(unsigned int);
3287 val = po->tp_reserve;
3288 data = &val;
3289 break;
3290 case PACKET_LOSS:
3291 if (len > sizeof(unsigned int))
3292 len = sizeof(unsigned int);
3293 val = po->tp_loss;
3294 data = &val;
3295 break;
3296 case PACKET_TIMESTAMP:
3297 if (len > sizeof(int))
3298 len = sizeof(int);
3299 val = po->tp_tstamp;
3300 data = &val;
3301 break;
3302 case PACKET_FANOUT:
3303 if (len > sizeof(int))
3304 len = sizeof(int);
3305 val = (po->fanout ?
3306 ((u32)po->fanout->id |
3307 ((u32)po->fanout->type << 16)) :
3308 0);
3309 data = &val;
3310 break;
3311 default:
3312 return -ENOPROTOOPT;
3313 }
3314
3315 if (put_user(len, optlen))
3316 return -EFAULT;
3317 if (copy_to_user(optval, data, len))
3318 return -EFAULT;
3319 return 0;
3320 }
3321
3322
3323 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3324 {
3325 struct sock *sk;
3326 struct hlist_node *node;
3327 struct net_device *dev = data;
3328 struct net *net = dev_net(dev);
3329
3330 rcu_read_lock();
3331 sk_for_each_rcu(sk, node, &net->packet.sklist) {
3332 struct packet_sock *po = pkt_sk(sk);
3333
3334 switch (msg) {
3335 case NETDEV_UNREGISTER:
3336 if (po->mclist)
3337 packet_dev_mclist(dev, po->mclist, -1);
3338 /* fallthrough */
3339
3340 case NETDEV_DOWN:
3341 if (dev->ifindex == po->ifindex) {
3342 spin_lock(&po->bind_lock);
3343 if (po->running) {
3344 __unregister_prot_hook(sk, false);
3345 sk->sk_err = ENETDOWN;
3346 if (!sock_flag(sk, SOCK_DEAD))
3347 sk->sk_error_report(sk);
3348 }
3349 if (msg == NETDEV_UNREGISTER) {
3350 po->ifindex = -1;
3351 if (po->prot_hook.dev)
3352 dev_put(po->prot_hook.dev);
3353 po->prot_hook.dev = NULL;
3354 }
3355 spin_unlock(&po->bind_lock);
3356 }
3357 break;
3358 case NETDEV_UP:
3359 if (dev->ifindex == po->ifindex) {
3360 spin_lock(&po->bind_lock);
3361 if (po->num)
3362 register_prot_hook(sk);
3363 spin_unlock(&po->bind_lock);
3364 }
3365 break;
3366 }
3367 }
3368 rcu_read_unlock();
3369 return NOTIFY_DONE;
3370 }
3371
3372
3373 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3374 unsigned long arg)
3375 {
3376 struct sock *sk = sock->sk;
3377
3378 switch (cmd) {
3379 case SIOCOUTQ:
3380 {
3381 int amount = sk_wmem_alloc_get(sk);
3382
3383 return put_user(amount, (int __user *)arg);
3384 }
3385 case SIOCINQ:
3386 {
3387 struct sk_buff *skb;
3388 int amount = 0;
3389
3390 spin_lock_bh(&sk->sk_receive_queue.lock);
3391 skb = skb_peek(&sk->sk_receive_queue);
3392 if (skb)
3393 amount = skb->len;
3394 spin_unlock_bh(&sk->sk_receive_queue.lock);
3395 return put_user(amount, (int __user *)arg);
3396 }
3397 case SIOCGSTAMP:
3398 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3399 case SIOCGSTAMPNS:
3400 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3401
3402 #ifdef CONFIG_INET
3403 case SIOCADDRT:
3404 case SIOCDELRT:
3405 case SIOCDARP:
3406 case SIOCGARP:
3407 case SIOCSARP:
3408 case SIOCGIFADDR:
3409 case SIOCSIFADDR:
3410 case SIOCGIFBRDADDR:
3411 case SIOCSIFBRDADDR:
3412 case SIOCGIFNETMASK:
3413 case SIOCSIFNETMASK:
3414 case SIOCGIFDSTADDR:
3415 case SIOCSIFDSTADDR:
3416 case SIOCSIFFLAGS:
3417 return inet_dgram_ops.ioctl(sock, cmd, arg);
3418 #endif
3419
3420 default:
3421 return -ENOIOCTLCMD;
3422 }
3423 return 0;
3424 }
3425
3426 static unsigned int packet_poll(struct file *file, struct socket *sock,
3427 poll_table *wait)
3428 {
3429 struct sock *sk = sock->sk;
3430 struct packet_sock *po = pkt_sk(sk);
3431 unsigned int mask = datagram_poll(file, sock, wait);
3432
3433 spin_lock_bh(&sk->sk_receive_queue.lock);
3434 if (po->rx_ring.pg_vec) {
3435 if (!packet_previous_rx_frame(po, &po->rx_ring,
3436 TP_STATUS_KERNEL))
3437 mask |= POLLIN | POLLRDNORM;
3438 }
3439 spin_unlock_bh(&sk->sk_receive_queue.lock);
3440 spin_lock_bh(&sk->sk_write_queue.lock);
3441 if (po->tx_ring.pg_vec) {
3442 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3443 mask |= POLLOUT | POLLWRNORM;
3444 }
3445 spin_unlock_bh(&sk->sk_write_queue.lock);
3446 return mask;
3447 }
3448
3449
3450 /* Dirty? Well, I still did not learn better way to account
3451 * for user mmaps.
3452 */
3453
3454 static void packet_mm_open(struct vm_area_struct *vma)
3455 {
3456 struct file *file = vma->vm_file;
3457 struct socket *sock = file->private_data;
3458 struct sock *sk = sock->sk;
3459
3460 if (sk)
3461 atomic_inc(&pkt_sk(sk)->mapped);
3462 }
3463
3464 static void packet_mm_close(struct vm_area_struct *vma)
3465 {
3466 struct file *file = vma->vm_file;
3467 struct socket *sock = file->private_data;
3468 struct sock *sk = sock->sk;
3469
3470 if (sk)
3471 atomic_dec(&pkt_sk(sk)->mapped);
3472 }
3473
3474 static const struct vm_operations_struct packet_mmap_ops = {
3475 .open = packet_mm_open,
3476 .close = packet_mm_close,
3477 };
3478
3479 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3480 unsigned int len)
3481 {
3482 int i;
3483
3484 for (i = 0; i < len; i++) {
3485 if (likely(pg_vec[i].buffer)) {
3486 if (is_vmalloc_addr(pg_vec[i].buffer))
3487 vfree(pg_vec[i].buffer);
3488 else
3489 free_pages((unsigned long)pg_vec[i].buffer,
3490 order);
3491 pg_vec[i].buffer = NULL;
3492 }
3493 }
3494 kfree(pg_vec);
3495 }
3496
3497 static char *alloc_one_pg_vec_page(unsigned long order)
3498 {
3499 char *buffer = NULL;
3500 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3501 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3502
3503 buffer = (char *) __get_free_pages(gfp_flags, order);
3504
3505 if (buffer)
3506 return buffer;
3507
3508 /*
3509 * __get_free_pages failed, fall back to vmalloc
3510 */
3511 buffer = vzalloc((1 << order) * PAGE_SIZE);
3512
3513 if (buffer)
3514 return buffer;
3515
3516 /*
3517 * vmalloc failed, lets dig into swap here
3518 */
3519 gfp_flags &= ~__GFP_NORETRY;
3520 buffer = (char *)__get_free_pages(gfp_flags, order);
3521 if (buffer)
3522 return buffer;
3523
3524 /*
3525 * complete and utter failure
3526 */
3527 return NULL;
3528 }
3529
3530 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3531 {
3532 unsigned int block_nr = req->tp_block_nr;
3533 struct pgv *pg_vec;
3534 int i;
3535
3536 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3537 if (unlikely(!pg_vec))
3538 goto out;
3539
3540 for (i = 0; i < block_nr; i++) {
3541 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3542 if (unlikely(!pg_vec[i].buffer))
3543 goto out_free_pgvec;
3544 }
3545
3546 out:
3547 return pg_vec;
3548
3549 out_free_pgvec:
3550 free_pg_vec(pg_vec, order, block_nr);
3551 pg_vec = NULL;
3552 goto out;
3553 }
3554
3555 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3556 int closing, int tx_ring)
3557 {
3558 struct pgv *pg_vec = NULL;
3559 struct packet_sock *po = pkt_sk(sk);
3560 int was_running, order = 0;
3561 struct packet_ring_buffer *rb;
3562 struct sk_buff_head *rb_queue;
3563 __be16 num;
3564 int err = -EINVAL;
3565 /* Added to avoid minimal code churn */
3566 struct tpacket_req *req = &req_u->req;
3567
3568 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3569 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3570 WARN(1, "Tx-ring is not supported.\n");
3571 goto out;
3572 }
3573
3574 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3575 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3576
3577 err = -EBUSY;
3578 if (!closing) {
3579 if (atomic_read(&po->mapped))
3580 goto out;
3581 if (atomic_read(&rb->pending))
3582 goto out;
3583 }
3584
3585 if (req->tp_block_nr) {
3586 /* Sanity tests and some calculations */
3587 err = -EBUSY;
3588 if (unlikely(rb->pg_vec))
3589 goto out;
3590
3591 switch (po->tp_version) {
3592 case TPACKET_V1:
3593 po->tp_hdrlen = TPACKET_HDRLEN;
3594 break;
3595 case TPACKET_V2:
3596 po->tp_hdrlen = TPACKET2_HDRLEN;
3597 break;
3598 case TPACKET_V3:
3599 po->tp_hdrlen = TPACKET3_HDRLEN;
3600 break;
3601 }
3602
3603 err = -EINVAL;
3604 if (unlikely((int)req->tp_block_size <= 0))
3605 goto out;
3606 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3607 goto out;
3608 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3609 po->tp_reserve))
3610 goto out;
3611 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3612 goto out;
3613
3614 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3615 if (unlikely(rb->frames_per_block <= 0))
3616 goto out;
3617 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3618 req->tp_frame_nr))
3619 goto out;
3620
3621 err = -ENOMEM;
3622 order = get_order(req->tp_block_size);
3623 pg_vec = alloc_pg_vec(req, order);
3624 if (unlikely(!pg_vec))
3625 goto out;
3626 switch (po->tp_version) {
3627 case TPACKET_V3:
3628 /* Transmit path is not supported. We checked
3629 * it above but just being paranoid
3630 */
3631 if (!tx_ring)
3632 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3633 break;
3634 default:
3635 break;
3636 }
3637 }
3638 /* Done */
3639 else {
3640 err = -EINVAL;
3641 if (unlikely(req->tp_frame_nr))
3642 goto out;
3643 }
3644
3645 lock_sock(sk);
3646
3647 /* Detach socket from network */
3648 spin_lock(&po->bind_lock);
3649 was_running = po->running;
3650 num = po->num;
3651 if (was_running) {
3652 po->num = 0;
3653 __unregister_prot_hook(sk, false);
3654 }
3655 spin_unlock(&po->bind_lock);
3656
3657 synchronize_net();
3658
3659 err = -EBUSY;
3660 mutex_lock(&po->pg_vec_lock);
3661 if (closing || atomic_read(&po->mapped) == 0) {
3662 err = 0;
3663 spin_lock_bh(&rb_queue->lock);
3664 swap(rb->pg_vec, pg_vec);
3665 rb->frame_max = (req->tp_frame_nr - 1);
3666 rb->head = 0;
3667 rb->frame_size = req->tp_frame_size;
3668 spin_unlock_bh(&rb_queue->lock);
3669
3670 swap(rb->pg_vec_order, order);
3671 swap(rb->pg_vec_len, req->tp_block_nr);
3672
3673 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3674 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3675 tpacket_rcv : packet_rcv;
3676 skb_queue_purge(rb_queue);
3677 if (atomic_read(&po->mapped))
3678 pr_err("packet_mmap: vma is busy: %d\n",
3679 atomic_read(&po->mapped));
3680 }
3681 mutex_unlock(&po->pg_vec_lock);
3682
3683 spin_lock(&po->bind_lock);
3684 if (was_running) {
3685 po->num = num;
3686 register_prot_hook(sk);
3687 }
3688 spin_unlock(&po->bind_lock);
3689 if (closing && (po->tp_version > TPACKET_V2)) {
3690 /* Because we don't support block-based V3 on tx-ring */
3691 if (!tx_ring)
3692 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3693 }
3694 release_sock(sk);
3695
3696 if (pg_vec)
3697 free_pg_vec(pg_vec, order, req->tp_block_nr);
3698 out:
3699 return err;
3700 }
3701
3702 static int packet_mmap(struct file *file, struct socket *sock,
3703 struct vm_area_struct *vma)
3704 {
3705 struct sock *sk = sock->sk;
3706 struct packet_sock *po = pkt_sk(sk);
3707 unsigned long size, expected_size;
3708 struct packet_ring_buffer *rb;
3709 unsigned long start;
3710 int err = -EINVAL;
3711 int i;
3712
3713 if (vma->vm_pgoff)
3714 return -EINVAL;
3715
3716 mutex_lock(&po->pg_vec_lock);
3717
3718 expected_size = 0;
3719 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3720 if (rb->pg_vec) {
3721 expected_size += rb->pg_vec_len
3722 * rb->pg_vec_pages
3723 * PAGE_SIZE;
3724 }
3725 }
3726
3727 if (expected_size == 0)
3728 goto out;
3729
3730 size = vma->vm_end - vma->vm_start;
3731 if (size != expected_size)
3732 goto out;
3733
3734 start = vma->vm_start;
3735 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3736 if (rb->pg_vec == NULL)
3737 continue;
3738
3739 for (i = 0; i < rb->pg_vec_len; i++) {
3740 struct page *page;
3741 void *kaddr = rb->pg_vec[i].buffer;
3742 int pg_num;
3743
3744 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3745 page = pgv_to_page(kaddr);
3746 err = vm_insert_page(vma, start, page);
3747 if (unlikely(err))
3748 goto out;
3749 start += PAGE_SIZE;
3750 kaddr += PAGE_SIZE;
3751 }
3752 }
3753 }
3754
3755 atomic_inc(&po->mapped);
3756 vma->vm_ops = &packet_mmap_ops;
3757 err = 0;
3758
3759 out:
3760 mutex_unlock(&po->pg_vec_lock);
3761 return err;
3762 }
3763
3764 static const struct proto_ops packet_ops_spkt = {
3765 .family = PF_PACKET,
3766 .owner = THIS_MODULE,
3767 .release = packet_release,
3768 .bind = packet_bind_spkt,
3769 .connect = sock_no_connect,
3770 .socketpair = sock_no_socketpair,
3771 .accept = sock_no_accept,
3772 .getname = packet_getname_spkt,
3773 .poll = datagram_poll,
3774 .ioctl = packet_ioctl,
3775 .listen = sock_no_listen,
3776 .shutdown = sock_no_shutdown,
3777 .setsockopt = sock_no_setsockopt,
3778 .getsockopt = sock_no_getsockopt,
3779 .sendmsg = packet_sendmsg_spkt,
3780 .recvmsg = packet_recvmsg,
3781 .mmap = sock_no_mmap,
3782 .sendpage = sock_no_sendpage,
3783 };
3784
3785 static const struct proto_ops packet_ops = {
3786 .family = PF_PACKET,
3787 .owner = THIS_MODULE,
3788 .release = packet_release,
3789 .bind = packet_bind,
3790 .connect = sock_no_connect,
3791 .socketpair = sock_no_socketpair,
3792 .accept = sock_no_accept,
3793 .getname = packet_getname,
3794 .poll = packet_poll,
3795 .ioctl = packet_ioctl,
3796 .listen = sock_no_listen,
3797 .shutdown = sock_no_shutdown,
3798 .setsockopt = packet_setsockopt,
3799 .getsockopt = packet_getsockopt,
3800 .sendmsg = packet_sendmsg,
3801 .recvmsg = packet_recvmsg,
3802 .mmap = packet_mmap,
3803 .sendpage = sock_no_sendpage,
3804 };
3805
3806 static const struct net_proto_family packet_family_ops = {
3807 .family = PF_PACKET,
3808 .create = packet_create,
3809 .owner = THIS_MODULE,
3810 };
3811
3812 static struct notifier_block packet_netdev_notifier = {
3813 .notifier_call = packet_notifier,
3814 };
3815
3816 #ifdef CONFIG_PROC_FS
3817
3818 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3819 __acquires(RCU)
3820 {
3821 struct net *net = seq_file_net(seq);
3822
3823 rcu_read_lock();
3824 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3825 }
3826
3827 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3828 {
3829 struct net *net = seq_file_net(seq);
3830 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3831 }
3832
3833 static void packet_seq_stop(struct seq_file *seq, void *v)
3834 __releases(RCU)
3835 {
3836 rcu_read_unlock();
3837 }
3838
3839 static int packet_seq_show(struct seq_file *seq, void *v)
3840 {
3841 if (v == SEQ_START_TOKEN)
3842 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3843 else {
3844 struct sock *s = sk_entry(v);
3845 const struct packet_sock *po = pkt_sk(s);
3846
3847 seq_printf(seq,
3848 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3849 s,
3850 atomic_read(&s->sk_refcnt),
3851 s->sk_type,
3852 ntohs(po->num),
3853 po->ifindex,
3854 po->running,
3855 atomic_read(&s->sk_rmem_alloc),
3856 sock_i_uid(s),
3857 sock_i_ino(s));
3858 }
3859
3860 return 0;
3861 }
3862
3863 static const struct seq_operations packet_seq_ops = {
3864 .start = packet_seq_start,
3865 .next = packet_seq_next,
3866 .stop = packet_seq_stop,
3867 .show = packet_seq_show,
3868 };
3869
3870 static int packet_seq_open(struct inode *inode, struct file *file)
3871 {
3872 return seq_open_net(inode, file, &packet_seq_ops,
3873 sizeof(struct seq_net_private));
3874 }
3875
3876 static const struct file_operations packet_seq_fops = {
3877 .owner = THIS_MODULE,
3878 .open = packet_seq_open,
3879 .read = seq_read,
3880 .llseek = seq_lseek,
3881 .release = seq_release_net,
3882 };
3883
3884 #endif
3885
3886 static int __net_init packet_net_init(struct net *net)
3887 {
3888 spin_lock_init(&net->packet.sklist_lock);
3889 INIT_HLIST_HEAD(&net->packet.sklist);
3890
3891 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3892 return -ENOMEM;
3893
3894 return 0;
3895 }
3896
3897 static void __net_exit packet_net_exit(struct net *net)
3898 {
3899 proc_net_remove(net, "packet");
3900 }
3901
3902 static struct pernet_operations packet_net_ops = {
3903 .init = packet_net_init,
3904 .exit = packet_net_exit,
3905 };
3906
3907
3908 static void __exit packet_exit(void)
3909 {
3910 unregister_netdevice_notifier(&packet_netdev_notifier);
3911 unregister_pernet_subsys(&packet_net_ops);
3912 sock_unregister(PF_PACKET);
3913 proto_unregister(&packet_proto);
3914 }
3915
3916 static int __init packet_init(void)
3917 {
3918 int rc = proto_register(&packet_proto, 0);
3919
3920 if (rc != 0)
3921 goto out;
3922
3923 sock_register(&packet_family_ops);
3924 register_pernet_subsys(&packet_net_ops);
3925 register_netdevice_notifier(&packet_netdev_notifier);
3926 out:
3927 return rc;
3928 }
3929
3930 module_init(packet_init);
3931 module_exit(packet_exit);
3932 MODULE_LICENSE("GPL");
3933 MODULE_ALIAS_NETPROTO(PF_PACKET);
kernel source for telekom puls (alcatel/mediatek)