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.
6 * PACKET - implements raw packet sockets.
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
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
42 * Johann Baudy : Added TX RING.
43 * Chetan Loke : Implemented TPACKET_V3 block abstraction
45 * Copyright (C) 2011, <lokec@ccs.neu.edu>
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.
55 #include <linux/types.h>
57 #include <linux/capability.h>
58 #include <linux/fcntl.h>
59 #include <linux/socket.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>
71 #include <net/protocol.h>
72 #include <linux/skbuff.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>
80 #include <asm/cacheflush.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>
94 #include <net/inet_common.h>
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
105 - packet socket receives packets with pulled ll header,
106 so that SOCK_RAW should push it back.
111 Incoming, dev->hard_header!=NULL
112 mac_header -> ll header
115 Outgoing, dev->hard_header!=NULL
116 mac_header -> ll header
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.
125 Outgoing, dev->hard_header==NULL
126 mac_header -> data. ll header is still not built!
130 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
136 dev->hard_header != NULL
137 mac_header -> ll header
140 dev->hard_header == NULL (ll header is added by device, we cannot control it)
144 We should set nh.raw on output to correct posistion,
145 packet classifier depends on it.
148 /* Private packet socket structures. */
150 struct packet_mclist {
151 struct packet_mclist *next;
156 unsigned char addr[MAX_ADDR_LEN];
158 /* identical to struct packet_mreq except it has
159 * a longer address field.
161 struct packet_mreq_max {
163 unsigned short mr_type;
164 unsigned short mr_alen;
165 unsigned char mr_address[MAX_ADDR_LEN];
168 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
169 int closing, int tx_ring);
172 #define V3_ALIGNMENT (8)
174 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
176 #define BLK_PLUS_PRIV(sz_of_priv) \
177 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
179 /* kbdq - kernel block descriptor queue */
180 struct tpacket_kbdq_core {
182 unsigned int feature_req_word;
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;
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.
193 unsigned short last_kactive_blk_num;
198 unsigned int knum_blocks;
199 uint64_t knxt_seq_num;
204 atomic_t blk_fill_in_prog;
206 /* Default is set to 8ms */
207 #define DEFAULT_PRB_RETIRE_TOV (8)
209 unsigned short retire_blk_tov;
210 unsigned short version;
211 unsigned long tov_in_jiffies;
213 /* timer to retire an outstanding block */
214 struct timer_list retire_blk_timer;
217 #define PGV_FROM_VMALLOC 1
222 struct packet_ring_buffer {
225 unsigned int frames_per_block;
226 unsigned int frame_size;
227 unsigned int frame_max;
229 unsigned int pg_vec_order;
230 unsigned int pg_vec_pages;
231 unsigned int pg_vec_len;
233 struct tpacket_kbdq_core prb_bdqc;
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)))
246 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
248 static void *packet_previous_frame(struct packet_sock *po,
249 struct packet_ring_buffer *rb,
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);
273 struct packet_fanout;
275 /* struct sock has to be the first member of packet_sock */
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;
283 spinlock_t bind_lock;
284 struct mutex pg_vec_lock;
285 unsigned int running:1, /* prot_hook is attached*/
289 int ifindex; /* bound device */
291 struct packet_mclist *mclist;
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 net_device __rcu *cached_dev;
299 struct packet_type prot_hook ____cacheline_aligned_in_smp;
302 #define PACKET_FANOUT_MAX 256
304 struct packet_fanout {
308 unsigned int num_members;
313 struct list_head list;
314 struct sock *arr[PACKET_FANOUT_MAX];
317 struct packet_type prot_hook ____cacheline_aligned_in_smp;
320 struct packet_skb_cb {
321 unsigned int origlen;
323 struct sockaddr_pkt pkt;
324 struct sockaddr_ll ll;
328 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
330 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
331 #define GET_PBLOCK_DESC(x, bid) \
332 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
333 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
334 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
335 #define GET_NEXT_PRB_BLK_NUM(x) \
336 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
337 ((x)->kactive_blk_num+1) : 0)
339 static struct packet_sock *pkt_sk(struct sock *sk)
341 return (struct packet_sock *)sk;
344 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
345 static void __fanout_link(struct sock *sk, struct packet_sock *po);
347 /* register_prot_hook must be invoked with the po->bind_lock held,
348 * or from a context in which asynchronous accesses to the packet
349 * socket is not possible (packet_create()).
351 static void register_prot_hook(struct sock *sk)
353 struct packet_sock *po = pkt_sk(sk);
357 __fanout_link(sk, po);
359 dev_add_pack(&po->prot_hook);
360 rcu_assign_pointer(po->cached_dev, po->prot_hook.dev);
368 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
369 * held. If the sync parameter is true, we will temporarily drop
370 * the po->bind_lock and do a synchronize_net to make sure no
371 * asynchronous packet processing paths still refer to the elements
372 * of po->prot_hook. If the sync parameter is false, it is the
373 * callers responsibility to take care of this.
375 static void __unregister_prot_hook(struct sock *sk, bool sync)
377 struct packet_sock *po = pkt_sk(sk);
381 __fanout_unlink(sk, po);
383 __dev_remove_pack(&po->prot_hook);
384 RCU_INIT_POINTER(po->cached_dev, NULL);
390 spin_unlock(&po->bind_lock);
392 spin_lock(&po->bind_lock);
396 static void unregister_prot_hook(struct sock *sk, bool sync)
398 struct packet_sock *po = pkt_sk(sk);
401 __unregister_prot_hook(sk, sync);
404 static inline __pure struct page *pgv_to_page(void *addr)
406 if (is_vmalloc_addr(addr))
407 return vmalloc_to_page(addr);
408 return virt_to_page(addr);
411 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
414 struct tpacket_hdr *h1;
415 struct tpacket2_hdr *h2;
420 switch (po->tp_version) {
422 h.h1->tp_status = status;
423 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
426 h.h2->tp_status = status;
427 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
431 WARN(1, "TPACKET version not supported.\n");
438 static int __packet_get_status(struct packet_sock *po, void *frame)
441 struct tpacket_hdr *h1;
442 struct tpacket2_hdr *h2;
449 switch (po->tp_version) {
451 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
452 return h.h1->tp_status;
454 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
455 return h.h2->tp_status;
458 WARN(1, "TPACKET version not supported.\n");
464 static void *packet_lookup_frame(struct packet_sock *po,
465 struct packet_ring_buffer *rb,
466 unsigned int position,
469 unsigned int pg_vec_pos, frame_offset;
471 struct tpacket_hdr *h1;
472 struct tpacket2_hdr *h2;
476 pg_vec_pos = position / rb->frames_per_block;
477 frame_offset = position % rb->frames_per_block;
479 h.raw = rb->pg_vec[pg_vec_pos].buffer +
480 (frame_offset * rb->frame_size);
482 if (status != __packet_get_status(po, h.raw))
488 static void *packet_current_frame(struct packet_sock *po,
489 struct packet_ring_buffer *rb,
492 return packet_lookup_frame(po, rb, rb->head, status);
495 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
497 del_timer_sync(&pkc->retire_blk_timer);
500 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
502 struct sk_buff_head *rb_queue)
504 struct tpacket_kbdq_core *pkc;
506 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
508 spin_lock_bh(&rb_queue->lock);
509 pkc->delete_blk_timer = 1;
510 spin_unlock_bh(&rb_queue->lock);
512 prb_del_retire_blk_timer(pkc);
515 static void prb_init_blk_timer(struct packet_sock *po,
516 struct tpacket_kbdq_core *pkc,
517 void (*func) (unsigned long))
519 init_timer(&pkc->retire_blk_timer);
520 pkc->retire_blk_timer.data = (long)po;
521 pkc->retire_blk_timer.function = func;
522 pkc->retire_blk_timer.expires = jiffies;
525 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
527 struct tpacket_kbdq_core *pkc;
532 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
533 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
536 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
537 int blk_size_in_bytes)
539 struct net_device *dev;
540 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
541 struct ethtool_cmd ecmd;
545 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
546 if (unlikely(!dev)) {
548 return DEFAULT_PRB_RETIRE_TOV;
550 err = __ethtool_get_settings(dev, &ecmd);
553 switch (ecmd.speed) {
563 * If the link speed is so slow you don't really
564 * need to worry about perf anyways
569 return DEFAULT_PRB_RETIRE_TOV;
573 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
585 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
586 union tpacket_req_u *req_u)
588 p1->feature_req_word = req_u->req3.tp_feature_req_word;
591 static void init_prb_bdqc(struct packet_sock *po,
592 struct packet_ring_buffer *rb,
594 union tpacket_req_u *req_u, int tx_ring)
596 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
597 struct tpacket_block_desc *pbd;
599 memset(p1, 0x0, sizeof(*p1));
601 p1->knxt_seq_num = 1;
603 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
604 p1->pkblk_start = (char *)pg_vec[0].buffer;
605 p1->kblk_size = req_u->req3.tp_block_size;
606 p1->knum_blocks = req_u->req3.tp_block_nr;
607 p1->hdrlen = po->tp_hdrlen;
608 p1->version = po->tp_version;
609 p1->last_kactive_blk_num = 0;
610 po->stats_u.stats3.tp_freeze_q_cnt = 0;
611 if (req_u->req3.tp_retire_blk_tov)
612 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
614 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
615 req_u->req3.tp_block_size);
616 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
617 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
619 prb_init_ft_ops(p1, req_u);
620 prb_setup_retire_blk_timer(po, tx_ring);
621 prb_open_block(p1, pbd);
624 /* Do NOT update the last_blk_num first.
625 * Assumes sk_buff_head lock is held.
627 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
629 mod_timer(&pkc->retire_blk_timer,
630 jiffies + pkc->tov_in_jiffies);
631 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
636 * 1) We refresh the timer only when we open a block.
637 * By doing this we don't waste cycles refreshing the timer
638 * on packet-by-packet basis.
640 * With a 1MB block-size, on a 1Gbps line, it will take
641 * i) ~8 ms to fill a block + ii) memcpy etc.
642 * In this cut we are not accounting for the memcpy time.
644 * So, if the user sets the 'tmo' to 10ms then the timer
645 * will never fire while the block is still getting filled
646 * (which is what we want). However, the user could choose
647 * to close a block early and that's fine.
649 * But when the timer does fire, we check whether or not to refresh it.
650 * Since the tmo granularity is in msecs, it is not too expensive
651 * to refresh the timer, lets say every '8' msecs.
652 * Either the user can set the 'tmo' or we can derive it based on
653 * a) line-speed and b) block-size.
654 * prb_calc_retire_blk_tmo() calculates the tmo.
657 static void prb_retire_rx_blk_timer_expired(unsigned long data)
659 struct packet_sock *po = (struct packet_sock *)data;
660 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
662 struct tpacket_block_desc *pbd;
664 spin_lock(&po->sk.sk_receive_queue.lock);
666 frozen = prb_queue_frozen(pkc);
667 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
669 if (unlikely(pkc->delete_blk_timer))
672 /* We only need to plug the race when the block is partially filled.
674 * lock(); increment BLOCK_NUM_PKTS; unlock()
675 * copy_bits() is in progress ...
676 * timer fires on other cpu:
677 * we can't retire the current block because copy_bits
681 if (BLOCK_NUM_PKTS(pbd)) {
682 while (atomic_read(&pkc->blk_fill_in_prog)) {
683 /* Waiting for skb_copy_bits to finish... */
688 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
690 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
691 if (!prb_dispatch_next_block(pkc, po))
696 /* Case 1. Queue was frozen because user-space was
699 if (prb_curr_blk_in_use(pkc, pbd)) {
701 * Ok, user-space is still behind.
702 * So just refresh the timer.
706 /* Case 2. queue was frozen,user-space caught up,
707 * now the link went idle && the timer fired.
708 * We don't have a block to close.So we open this
709 * block and restart the timer.
710 * opening a block thaws the queue,restarts timer
711 * Thawing/timer-refresh is a side effect.
713 prb_open_block(pkc, pbd);
720 _prb_refresh_rx_retire_blk_timer(pkc);
723 spin_unlock(&po->sk.sk_receive_queue.lock);
726 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
727 struct tpacket_block_desc *pbd1, __u32 status)
729 /* Flush everything minus the block header */
731 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
736 /* Skip the block header(we know header WILL fit in 4K) */
739 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
740 for (; start < end; start += PAGE_SIZE)
741 flush_dcache_page(pgv_to_page(start));
746 /* Now update the block status. */
748 BLOCK_STATUS(pbd1) = status;
750 /* Flush the block header */
752 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
754 flush_dcache_page(pgv_to_page(start));
764 * 2) Increment active_blk_num
766 * Note:We DONT refresh the timer on purpose.
767 * Because almost always the next block will be opened.
769 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
770 struct tpacket_block_desc *pbd1,
771 struct packet_sock *po, unsigned int stat)
773 __u32 status = TP_STATUS_USER | stat;
775 struct tpacket3_hdr *last_pkt;
776 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
778 if (po->stats.tp_drops)
779 status |= TP_STATUS_LOSING;
781 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
782 last_pkt->tp_next_offset = 0;
784 /* Get the ts of the last pkt */
785 if (BLOCK_NUM_PKTS(pbd1)) {
786 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
787 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
789 /* Ok, we tmo'd - so get the current time */
792 h1->ts_last_pkt.ts_sec = ts.tv_sec;
793 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
798 /* Flush the block */
799 prb_flush_block(pkc1, pbd1, status);
801 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
804 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
806 pkc->reset_pending_on_curr_blk = 0;
810 * Side effect of opening a block:
812 * 1) prb_queue is thawed.
813 * 2) retire_blk_timer is refreshed.
816 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
817 struct tpacket_block_desc *pbd1)
820 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
824 /* We could have just memset this but we will lose the
825 * flexibility of making the priv area sticky
827 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
828 BLOCK_NUM_PKTS(pbd1) = 0;
829 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
831 h1->ts_first_pkt.ts_sec = ts.tv_sec;
832 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
833 pkc1->pkblk_start = (char *)pbd1;
834 pkc1->nxt_offset = (char *)(pkc1->pkblk_start +
835 BLK_PLUS_PRIV(pkc1->blk_sizeof_priv));
836 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
837 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
838 pbd1->version = pkc1->version;
839 pkc1->prev = pkc1->nxt_offset;
840 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
841 prb_thaw_queue(pkc1);
842 _prb_refresh_rx_retire_blk_timer(pkc1);
848 * Queue freeze logic:
849 * 1) Assume tp_block_nr = 8 blocks.
850 * 2) At time 't0', user opens Rx ring.
851 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
852 * 4) user-space is either sleeping or processing block '0'.
853 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
854 * it will close block-7,loop around and try to fill block '0'.
856 * __packet_lookup_frame_in_block
857 * prb_retire_current_block()
858 * prb_dispatch_next_block()
859 * |->(BLOCK_STATUS == USER) evaluates to true
860 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
861 * 6) Now there are two cases:
862 * 6.1) Link goes idle right after the queue is frozen.
863 * But remember, the last open_block() refreshed the timer.
864 * When this timer expires,it will refresh itself so that we can
865 * re-open block-0 in near future.
866 * 6.2) Link is busy and keeps on receiving packets. This is a simple
867 * case and __packet_lookup_frame_in_block will check if block-0
868 * is free and can now be re-used.
870 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
871 struct packet_sock *po)
873 pkc->reset_pending_on_curr_blk = 1;
874 po->stats_u.stats3.tp_freeze_q_cnt++;
877 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
880 * If the next block is free then we will dispatch it
881 * and return a good offset.
882 * Else, we will freeze the queue.
883 * So, caller must check the return value.
885 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
886 struct packet_sock *po)
888 struct tpacket_block_desc *pbd;
892 /* 1. Get current block num */
893 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
895 /* 2. If this block is currently in_use then freeze the queue */
896 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
897 prb_freeze_queue(pkc, po);
903 * open this block and return the offset where the first packet
904 * needs to get stored.
906 prb_open_block(pkc, pbd);
907 return (void *)pkc->nxt_offset;
910 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
911 struct packet_sock *po, unsigned int status)
913 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
915 /* retire/close the current block */
916 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
918 * Plug the case where copy_bits() is in progress on
919 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
920 * have space to copy the pkt in the current block and
921 * called prb_retire_current_block()
923 * We don't need to worry about the TMO case because
924 * the timer-handler already handled this case.
926 if (!(status & TP_STATUS_BLK_TMO)) {
927 while (atomic_read(&pkc->blk_fill_in_prog)) {
928 /* Waiting for skb_copy_bits to finish... */
932 prb_close_block(pkc, pbd, po, status);
937 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
938 struct tpacket_block_desc *pbd)
940 return TP_STATUS_USER & BLOCK_STATUS(pbd);
943 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
945 return pkc->reset_pending_on_curr_blk;
948 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
950 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
951 atomic_dec(&pkc->blk_fill_in_prog);
954 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
955 struct tpacket3_hdr *ppd)
957 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
960 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
961 struct tpacket3_hdr *ppd)
963 ppd->hv1.tp_rxhash = 0;
966 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
967 struct tpacket3_hdr *ppd)
969 if (vlan_tx_tag_present(pkc->skb)) {
970 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
971 ppd->tp_status = TP_STATUS_VLAN_VALID;
973 ppd->hv1.tp_vlan_tci = ppd->tp_status = 0;
977 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
978 struct tpacket3_hdr *ppd)
980 prb_fill_vlan_info(pkc, ppd);
982 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
983 prb_fill_rxhash(pkc, ppd);
985 prb_clear_rxhash(pkc, ppd);
988 static void prb_fill_curr_block(char *curr,
989 struct tpacket_kbdq_core *pkc,
990 struct tpacket_block_desc *pbd,
993 struct tpacket3_hdr *ppd;
995 ppd = (struct tpacket3_hdr *)curr;
996 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
998 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
999 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1000 BLOCK_NUM_PKTS(pbd) += 1;
1001 atomic_inc(&pkc->blk_fill_in_prog);
1002 prb_run_all_ft_ops(pkc, ppd);
1005 /* Assumes caller has the sk->rx_queue.lock */
1006 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1007 struct sk_buff *skb,
1012 struct tpacket_kbdq_core *pkc;
1013 struct tpacket_block_desc *pbd;
1016 pkc = GET_PBDQC_FROM_RB(((struct packet_ring_buffer *)&po->rx_ring));
1017 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1019 /* Queue is frozen when user space is lagging behind */
1020 if (prb_queue_frozen(pkc)) {
1022 * Check if that last block which caused the queue to freeze,
1023 * is still in_use by user-space.
1025 if (prb_curr_blk_in_use(pkc, pbd)) {
1026 /* Can't record this packet */
1030 * Ok, the block was released by user-space.
1031 * Now let's open that block.
1032 * opening a block also thaws the queue.
1033 * Thawing is a side effect.
1035 prb_open_block(pkc, pbd);
1040 curr = pkc->nxt_offset;
1042 end = (char *) ((char *)pbd + pkc->kblk_size);
1044 /* first try the current block */
1045 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1046 prb_fill_curr_block(curr, pkc, pbd, len);
1047 return (void *)curr;
1050 /* Ok, close the current block */
1051 prb_retire_current_block(pkc, po, 0);
1053 /* Now, try to dispatch the next block */
1054 curr = (char *)prb_dispatch_next_block(pkc, po);
1056 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1057 prb_fill_curr_block(curr, pkc, pbd, len);
1058 return (void *)curr;
1062 * No free blocks are available.user_space hasn't caught up yet.
1063 * Queue was just frozen and now this packet will get dropped.
1068 static void *packet_current_rx_frame(struct packet_sock *po,
1069 struct sk_buff *skb,
1070 int status, unsigned int len)
1073 switch (po->tp_version) {
1076 curr = packet_lookup_frame(po, &po->rx_ring,
1077 po->rx_ring.head, status);
1080 return __packet_lookup_frame_in_block(po, skb, status, len);
1082 WARN(1, "TPACKET version not supported\n");
1088 static void *prb_lookup_block(struct packet_sock *po,
1089 struct packet_ring_buffer *rb,
1090 unsigned int previous,
1093 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1094 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, previous);
1096 if (status != BLOCK_STATUS(pbd))
1101 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1104 if (rb->prb_bdqc.kactive_blk_num)
1105 prev = rb->prb_bdqc.kactive_blk_num-1;
1107 prev = rb->prb_bdqc.knum_blocks-1;
1111 /* Assumes caller has held the rx_queue.lock */
1112 static void *__prb_previous_block(struct packet_sock *po,
1113 struct packet_ring_buffer *rb,
1116 unsigned int previous = prb_previous_blk_num(rb);
1117 return prb_lookup_block(po, rb, previous, status);
1120 static void *packet_previous_rx_frame(struct packet_sock *po,
1121 struct packet_ring_buffer *rb,
1124 if (po->tp_version <= TPACKET_V2)
1125 return packet_previous_frame(po, rb, status);
1127 return __prb_previous_block(po, rb, status);
1130 static void packet_increment_rx_head(struct packet_sock *po,
1131 struct packet_ring_buffer *rb)
1133 switch (po->tp_version) {
1136 return packet_increment_head(rb);
1139 WARN(1, "TPACKET version not supported.\n");
1145 static void *packet_previous_frame(struct packet_sock *po,
1146 struct packet_ring_buffer *rb,
1149 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1150 return packet_lookup_frame(po, rb, previous, status);
1153 static void packet_increment_head(struct packet_ring_buffer *buff)
1155 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1158 static void packet_sock_destruct(struct sock *sk)
1160 skb_queue_purge(&sk->sk_error_queue);
1162 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1163 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1165 if (!sock_flag(sk, SOCK_DEAD)) {
1166 pr_err("Attempt to release alive packet socket: %p\n", sk);
1170 sk_refcnt_debug_dec(sk);
1173 static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1175 u32 idx, hash = skb->rxhash;
1177 idx = ((u64)hash * num) >> 32;
1182 static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1184 unsigned int val = atomic_inc_return(&f->rr_cur);
1186 return f->arr[val % num];
1189 static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
1191 unsigned int cpu = smp_processor_id();
1193 return f->arr[cpu % num];
1196 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1197 struct packet_type *pt, struct net_device *orig_dev)
1199 struct packet_fanout *f = pt->af_packet_priv;
1200 unsigned int num = ACCESS_ONCE(f->num_members);
1201 struct packet_sock *po;
1204 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1211 case PACKET_FANOUT_HASH:
1214 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1218 skb_get_rxhash(skb);
1219 sk = fanout_demux_hash(f, skb, num);
1221 case PACKET_FANOUT_LB:
1222 sk = fanout_demux_lb(f, skb, num);
1224 case PACKET_FANOUT_CPU:
1225 sk = fanout_demux_cpu(f, skb, num);
1231 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1234 static DEFINE_MUTEX(fanout_mutex);
1235 static LIST_HEAD(fanout_list);
1237 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1239 struct packet_fanout *f = po->fanout;
1241 spin_lock(&f->lock);
1242 f->arr[f->num_members] = sk;
1245 spin_unlock(&f->lock);
1248 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1250 struct packet_fanout *f = po->fanout;
1253 spin_lock(&f->lock);
1254 for (i = 0; i < f->num_members; i++) {
1255 if (f->arr[i] == sk)
1258 BUG_ON(i >= f->num_members);
1259 f->arr[i] = f->arr[f->num_members - 1];
1261 spin_unlock(&f->lock);
1264 bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
1266 if (sk->sk_family != PF_PACKET)
1269 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1272 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1274 struct packet_sock *po = pkt_sk(sk);
1275 struct packet_fanout *f, *match;
1276 u8 type = type_flags & 0xff;
1277 u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
1281 case PACKET_FANOUT_HASH:
1282 case PACKET_FANOUT_LB:
1283 case PACKET_FANOUT_CPU:
1295 mutex_lock(&fanout_mutex);
1297 list_for_each_entry(f, &fanout_list, list) {
1299 read_pnet(&f->net) == sock_net(sk)) {
1305 if (match && match->defrag != defrag)
1309 match = kzalloc(sizeof(*match), GFP_KERNEL);
1312 write_pnet(&match->net, sock_net(sk));
1315 match->defrag = defrag;
1316 atomic_set(&match->rr_cur, 0);
1317 INIT_LIST_HEAD(&match->list);
1318 spin_lock_init(&match->lock);
1319 atomic_set(&match->sk_ref, 0);
1320 match->prot_hook.type = po->prot_hook.type;
1321 match->prot_hook.dev = po->prot_hook.dev;
1322 match->prot_hook.func = packet_rcv_fanout;
1323 match->prot_hook.af_packet_priv = match;
1324 match->prot_hook.id_match = match_fanout_group;
1325 dev_add_pack(&match->prot_hook);
1326 list_add(&match->list, &fanout_list);
1329 if (match->type == type &&
1330 match->prot_hook.type == po->prot_hook.type &&
1331 match->prot_hook.dev == po->prot_hook.dev) {
1333 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1334 __dev_remove_pack(&po->prot_hook);
1336 atomic_inc(&match->sk_ref);
1337 __fanout_link(sk, po);
1342 mutex_unlock(&fanout_mutex);
1346 static void fanout_release(struct sock *sk)
1348 struct packet_sock *po = pkt_sk(sk);
1349 struct packet_fanout *f;
1357 mutex_lock(&fanout_mutex);
1358 if (atomic_dec_and_test(&f->sk_ref)) {
1360 dev_remove_pack(&f->prot_hook);
1363 mutex_unlock(&fanout_mutex);
1366 static const struct proto_ops packet_ops;
1368 static const struct proto_ops packet_ops_spkt;
1370 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1371 struct packet_type *pt, struct net_device *orig_dev)
1374 struct sockaddr_pkt *spkt;
1377 * When we registered the protocol we saved the socket in the data
1378 * field for just this event.
1381 sk = pt->af_packet_priv;
1384 * Yank back the headers [hope the device set this
1385 * right or kerboom...]
1387 * Incoming packets have ll header pulled,
1390 * For outgoing ones skb->data == skb_mac_header(skb)
1391 * so that this procedure is noop.
1394 if (skb->pkt_type == PACKET_LOOPBACK)
1397 if (!net_eq(dev_net(dev), sock_net(sk)))
1400 skb = skb_share_check(skb, GFP_ATOMIC);
1404 /* drop any routing info */
1407 /* drop conntrack reference */
1410 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1412 skb_push(skb, skb->data - skb_mac_header(skb));
1415 * The SOCK_PACKET socket receives _all_ frames.
1418 spkt->spkt_family = dev->type;
1419 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1420 spkt->spkt_protocol = skb->protocol;
1423 * Charge the memory to the socket. This is done specifically
1424 * to prevent sockets using all the memory up.
1427 if (sock_queue_rcv_skb(sk, skb) == 0)
1438 * Output a raw packet to a device layer. This bypasses all the other
1439 * protocol layers and you must therefore supply it with a complete frame
1442 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1443 struct msghdr *msg, size_t len)
1445 struct sock *sk = sock->sk;
1446 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1447 struct sk_buff *skb = NULL;
1448 struct net_device *dev;
1453 * Get and verify the address.
1457 if (msg->msg_namelen < sizeof(struct sockaddr))
1459 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1460 proto = saddr->spkt_protocol;
1462 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1465 * Find the device first to size check it
1468 saddr->spkt_device[13] = 0;
1471 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1477 if (!(dev->flags & IFF_UP))
1481 * You may not queue a frame bigger than the mtu. This is the lowest level
1482 * raw protocol and you must do your own fragmentation at this level.
1486 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
1490 size_t reserved = LL_RESERVED_SPACE(dev);
1491 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1494 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
1497 /* FIXME: Save some space for broken drivers that write a hard
1498 * header at transmission time by themselves. PPP is the notable
1499 * one here. This should really be fixed at the driver level.
1501 skb_reserve(skb, reserved);
1502 skb_reset_network_header(skb);
1504 /* Try to align data part correctly */
1509 skb_reset_network_header(skb);
1511 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1517 if (len > (dev->mtu + dev->hard_header_len)) {
1518 /* Earlier code assumed this would be a VLAN pkt,
1519 * double-check this now that we have the actual
1522 struct ethhdr *ehdr;
1523 skb_reset_mac_header(skb);
1524 ehdr = eth_hdr(skb);
1525 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1531 skb->protocol = proto;
1533 skb->priority = sk->sk_priority;
1534 skb->mark = sk->sk_mark;
1535 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1539 dev_queue_xmit(skb);
1550 static unsigned int run_filter(const struct sk_buff *skb,
1551 const struct sock *sk,
1554 struct sk_filter *filter;
1557 filter = rcu_dereference(sk->sk_filter);
1559 res = SK_RUN_FILTER(filter, skb);
1566 * This function makes lazy skb cloning in hope that most of packets
1567 * are discarded by BPF.
1569 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1570 * and skb->cb are mangled. It works because (and until) packets
1571 * falling here are owned by current CPU. Output packets are cloned
1572 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1573 * sequencially, so that if we return skb to original state on exit,
1574 * we will not harm anyone.
1577 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1578 struct packet_type *pt, struct net_device *orig_dev)
1581 struct sockaddr_ll *sll;
1582 struct packet_sock *po;
1583 u8 *skb_head = skb->data;
1584 int skb_len = skb->len;
1585 unsigned int snaplen, res;
1587 if (skb->pkt_type == PACKET_LOOPBACK)
1590 sk = pt->af_packet_priv;
1593 if (!net_eq(dev_net(dev), sock_net(sk)))
1598 if (dev->header_ops) {
1599 /* The device has an explicit notion of ll header,
1600 * exported to higher levels.
1602 * Otherwise, the device hides details of its frame
1603 * structure, so that corresponding packet head is
1604 * never delivered to user.
1606 if (sk->sk_type != SOCK_DGRAM)
1607 skb_push(skb, skb->data - skb_mac_header(skb));
1608 else if (skb->pkt_type == PACKET_OUTGOING) {
1609 /* Special case: outgoing packets have ll header at head */
1610 skb_pull(skb, skb_network_offset(skb));
1616 res = run_filter(skb, sk, snaplen);
1618 goto drop_n_restore;
1622 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1625 if (skb_shared(skb)) {
1626 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1630 if (skb_head != skb->data) {
1631 skb->data = skb_head;
1638 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1641 sll = &PACKET_SKB_CB(skb)->sa.ll;
1642 sll->sll_family = AF_PACKET;
1643 sll->sll_hatype = dev->type;
1644 sll->sll_protocol = skb->protocol;
1645 sll->sll_pkttype = skb->pkt_type;
1646 if (unlikely(po->origdev))
1647 sll->sll_ifindex = orig_dev->ifindex;
1649 sll->sll_ifindex = dev->ifindex;
1651 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1653 PACKET_SKB_CB(skb)->origlen = skb->len;
1655 if (pskb_trim(skb, snaplen))
1658 skb_set_owner_r(skb, sk);
1662 /* drop conntrack reference */
1665 spin_lock(&sk->sk_receive_queue.lock);
1666 po->stats.tp_packets++;
1667 skb->dropcount = atomic_read(&sk->sk_drops);
1668 __skb_queue_tail(&sk->sk_receive_queue, skb);
1669 spin_unlock(&sk->sk_receive_queue.lock);
1670 sk->sk_data_ready(sk, skb->len);
1674 spin_lock(&sk->sk_receive_queue.lock);
1675 po->stats.tp_drops++;
1676 atomic_inc(&sk->sk_drops);
1677 spin_unlock(&sk->sk_receive_queue.lock);
1680 if (skb_head != skb->data && skb_shared(skb)) {
1681 skb->data = skb_head;
1689 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1690 struct packet_type *pt, struct net_device *orig_dev)
1693 struct packet_sock *po;
1694 struct sockaddr_ll *sll;
1696 struct tpacket_hdr *h1;
1697 struct tpacket2_hdr *h2;
1698 struct tpacket3_hdr *h3;
1701 u8 *skb_head = skb->data;
1702 int skb_len = skb->len;
1703 unsigned int snaplen, res;
1704 unsigned long status = TP_STATUS_USER;
1705 unsigned short macoff, netoff, hdrlen;
1706 struct sk_buff *copy_skb = NULL;
1709 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1711 if (skb->pkt_type == PACKET_LOOPBACK)
1714 sk = pt->af_packet_priv;
1717 if (!net_eq(dev_net(dev), sock_net(sk)))
1720 if (dev->header_ops) {
1721 if (sk->sk_type != SOCK_DGRAM)
1722 skb_push(skb, skb->data - skb_mac_header(skb));
1723 else if (skb->pkt_type == PACKET_OUTGOING) {
1724 /* Special case: outgoing packets have ll header at head */
1725 skb_pull(skb, skb_network_offset(skb));
1729 if (skb->ip_summed == CHECKSUM_PARTIAL)
1730 status |= TP_STATUS_CSUMNOTREADY;
1734 res = run_filter(skb, sk, snaplen);
1736 goto drop_n_restore;
1740 if (sk->sk_type == SOCK_DGRAM) {
1741 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1744 unsigned maclen = skb_network_offset(skb);
1745 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1746 (maclen < 16 ? 16 : maclen)) +
1748 macoff = netoff - maclen;
1750 if (po->tp_version <= TPACKET_V2) {
1751 if (macoff + snaplen > po->rx_ring.frame_size) {
1752 if (po->copy_thresh &&
1753 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1754 if (skb_shared(skb)) {
1755 copy_skb = skb_clone(skb, GFP_ATOMIC);
1757 copy_skb = skb_get(skb);
1758 skb_head = skb->data;
1761 skb_set_owner_r(copy_skb, sk);
1763 snaplen = po->rx_ring.frame_size - macoff;
1764 if ((int)snaplen < 0)
1768 spin_lock(&sk->sk_receive_queue.lock);
1769 h.raw = packet_current_rx_frame(po, skb,
1770 TP_STATUS_KERNEL, (macoff+snaplen));
1773 if (po->tp_version <= TPACKET_V2) {
1774 packet_increment_rx_head(po, &po->rx_ring);
1776 * LOSING will be reported till you read the stats,
1777 * because it's COR - Clear On Read.
1778 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1781 if (po->stats.tp_drops)
1782 status |= TP_STATUS_LOSING;
1784 po->stats.tp_packets++;
1786 status |= TP_STATUS_COPY;
1787 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1789 spin_unlock(&sk->sk_receive_queue.lock);
1791 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1793 switch (po->tp_version) {
1795 h.h1->tp_len = skb->len;
1796 h.h1->tp_snaplen = snaplen;
1797 h.h1->tp_mac = macoff;
1798 h.h1->tp_net = netoff;
1799 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1800 && shhwtstamps->syststamp.tv64)
1801 tv = ktime_to_timeval(shhwtstamps->syststamp);
1802 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1803 && shhwtstamps->hwtstamp.tv64)
1804 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1805 else if (skb->tstamp.tv64)
1806 tv = ktime_to_timeval(skb->tstamp);
1808 do_gettimeofday(&tv);
1809 h.h1->tp_sec = tv.tv_sec;
1810 h.h1->tp_usec = tv.tv_usec;
1811 hdrlen = sizeof(*h.h1);
1814 h.h2->tp_len = skb->len;
1815 h.h2->tp_snaplen = snaplen;
1816 h.h2->tp_mac = macoff;
1817 h.h2->tp_net = netoff;
1818 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1819 && shhwtstamps->syststamp.tv64)
1820 ts = ktime_to_timespec(shhwtstamps->syststamp);
1821 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1822 && shhwtstamps->hwtstamp.tv64)
1823 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1824 else if (skb->tstamp.tv64)
1825 ts = ktime_to_timespec(skb->tstamp);
1827 getnstimeofday(&ts);
1828 h.h2->tp_sec = ts.tv_sec;
1829 h.h2->tp_nsec = ts.tv_nsec;
1830 if (vlan_tx_tag_present(skb)) {
1831 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1832 status |= TP_STATUS_VLAN_VALID;
1834 h.h2->tp_vlan_tci = 0;
1836 h.h2->tp_padding = 0;
1837 hdrlen = sizeof(*h.h2);
1840 /* tp_nxt_offset,vlan are already populated above.
1841 * So DONT clear those fields here
1843 h.h3->tp_status |= status;
1844 h.h3->tp_len = skb->len;
1845 h.h3->tp_snaplen = snaplen;
1846 h.h3->tp_mac = macoff;
1847 h.h3->tp_net = netoff;
1848 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1849 && shhwtstamps->syststamp.tv64)
1850 ts = ktime_to_timespec(shhwtstamps->syststamp);
1851 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1852 && shhwtstamps->hwtstamp.tv64)
1853 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1854 else if (skb->tstamp.tv64)
1855 ts = ktime_to_timespec(skb->tstamp);
1857 getnstimeofday(&ts);
1858 h.h3->tp_sec = ts.tv_sec;
1859 h.h3->tp_nsec = ts.tv_nsec;
1860 hdrlen = sizeof(*h.h3);
1866 sll = h.raw + TPACKET_ALIGN(hdrlen);
1867 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1868 sll->sll_family = AF_PACKET;
1869 sll->sll_hatype = dev->type;
1870 sll->sll_protocol = skb->protocol;
1871 sll->sll_pkttype = skb->pkt_type;
1872 if (unlikely(po->origdev))
1873 sll->sll_ifindex = orig_dev->ifindex;
1875 sll->sll_ifindex = dev->ifindex;
1878 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1882 if (po->tp_version <= TPACKET_V2) {
1883 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1884 + macoff + snaplen);
1885 for (start = h.raw; start < end; start += PAGE_SIZE)
1886 flush_dcache_page(pgv_to_page(start));
1891 if (po->tp_version <= TPACKET_V2)
1892 __packet_set_status(po, h.raw, status);
1894 prb_clear_blk_fill_status(&po->rx_ring);
1896 sk->sk_data_ready(sk, 0);
1899 if (skb_head != skb->data && skb_shared(skb)) {
1900 skb->data = skb_head;
1908 po->stats.tp_drops++;
1909 spin_unlock(&sk->sk_receive_queue.lock);
1911 sk->sk_data_ready(sk, 0);
1912 kfree_skb(copy_skb);
1913 goto drop_n_restore;
1916 static void tpacket_destruct_skb(struct sk_buff *skb)
1918 struct packet_sock *po = pkt_sk(skb->sk);
1921 if (likely(po->tx_ring.pg_vec)) {
1922 ph = skb_shinfo(skb)->destructor_arg;
1923 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1924 atomic_dec(&po->tx_ring.pending);
1925 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1931 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1932 void *frame, struct net_device *dev, int size_max,
1933 __be16 proto, unsigned char *addr)
1936 struct tpacket_hdr *h1;
1937 struct tpacket2_hdr *h2;
1940 int to_write, offset, len, tp_len, nr_frags, len_max;
1941 struct socket *sock = po->sk.sk_socket;
1948 skb->protocol = proto;
1950 skb->priority = po->sk.sk_priority;
1951 skb->mark = po->sk.sk_mark;
1952 skb_shinfo(skb)->destructor_arg = ph.raw;
1954 switch (po->tp_version) {
1956 tp_len = ph.h2->tp_len;
1959 tp_len = ph.h1->tp_len;
1962 if (unlikely(tp_len > size_max)) {
1963 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1967 skb_reserve(skb, LL_RESERVED_SPACE(dev));
1968 skb_reset_network_header(skb);
1970 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1973 if (sock->type == SOCK_DGRAM) {
1974 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1976 if (unlikely(err < 0))
1978 } else if (dev->hard_header_len) {
1979 /* net device doesn't like empty head */
1980 if (unlikely(tp_len <= dev->hard_header_len)) {
1981 pr_err("packet size is too short (%d < %d)\n",
1982 tp_len, dev->hard_header_len);
1986 skb_push(skb, dev->hard_header_len);
1987 err = skb_store_bits(skb, 0, data,
1988 dev->hard_header_len);
1992 data += dev->hard_header_len;
1993 to_write -= dev->hard_header_len;
1997 offset = offset_in_page(data);
1998 len_max = PAGE_SIZE - offset;
1999 len = ((to_write > len_max) ? len_max : to_write);
2001 skb->data_len = to_write;
2002 skb->len += to_write;
2003 skb->truesize += to_write;
2004 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2006 while (likely(to_write)) {
2007 nr_frags = skb_shinfo(skb)->nr_frags;
2009 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2010 pr_err("Packet exceed the number of skb frags(%lu)\n",
2015 page = pgv_to_page(data);
2017 flush_dcache_page(page);
2019 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2022 len_max = PAGE_SIZE;
2023 len = ((to_write > len_max) ? len_max : to_write);
2029 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
2031 struct net_device *dev;
2034 dev = rcu_dereference(po->cached_dev);
2042 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2044 struct sk_buff *skb;
2045 struct net_device *dev;
2047 int err, reserve = 0;
2049 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2050 int tp_len, size_max;
2051 unsigned char *addr;
2055 mutex_lock(&po->pg_vec_lock);
2058 if (saddr == NULL) {
2059 dev = packet_cached_dev_get(po);
2064 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2066 if (msg->msg_namelen < (saddr->sll_halen
2067 + offsetof(struct sockaddr_ll,
2070 proto = saddr->sll_protocol;
2071 addr = saddr->sll_addr;
2072 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2076 if (unlikely(dev == NULL))
2079 if (unlikely(!(dev->flags & IFF_UP)))
2082 reserve = dev->hard_header_len;
2084 size_max = po->tx_ring.frame_size
2085 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2087 if (size_max > dev->mtu + reserve)
2088 size_max = dev->mtu + reserve;
2091 ph = packet_current_frame(po, &po->tx_ring,
2092 TP_STATUS_SEND_REQUEST);
2094 if (unlikely(ph == NULL)) {
2099 status = TP_STATUS_SEND_REQUEST;
2100 skb = sock_alloc_send_skb(&po->sk,
2101 LL_ALLOCATED_SPACE(dev)
2102 + sizeof(struct sockaddr_ll),
2105 if (unlikely(skb == NULL))
2108 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2111 if (unlikely(tp_len < 0)) {
2113 __packet_set_status(po, ph,
2114 TP_STATUS_AVAILABLE);
2115 packet_increment_head(&po->tx_ring);
2119 status = TP_STATUS_WRONG_FORMAT;
2125 skb->destructor = tpacket_destruct_skb;
2126 __packet_set_status(po, ph, TP_STATUS_SENDING);
2127 atomic_inc(&po->tx_ring.pending);
2129 status = TP_STATUS_SEND_REQUEST;
2130 err = dev_queue_xmit(skb);
2131 if (unlikely(err > 0)) {
2132 err = net_xmit_errno(err);
2133 if (err && __packet_get_status(po, ph) ==
2134 TP_STATUS_AVAILABLE) {
2135 /* skb was destructed already */
2140 * skb was dropped but not destructed yet;
2141 * let's treat it like congestion or err < 0
2145 packet_increment_head(&po->tx_ring);
2147 } while (likely((ph != NULL) ||
2148 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2149 (atomic_read(&po->tx_ring.pending))))
2156 __packet_set_status(po, ph, status);
2161 mutex_unlock(&po->pg_vec_lock);
2165 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2166 size_t reserve, size_t len,
2167 size_t linear, int noblock,
2170 struct sk_buff *skb;
2172 /* Under a page? Don't bother with paged skb. */
2173 if (prepad + len < PAGE_SIZE || !linear)
2176 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2181 skb_reserve(skb, reserve);
2182 skb_put(skb, linear);
2183 skb->data_len = len - linear;
2184 skb->len += len - linear;
2189 static int packet_snd(struct socket *sock,
2190 struct msghdr *msg, size_t len)
2192 struct sock *sk = sock->sk;
2193 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2194 struct sk_buff *skb;
2195 struct net_device *dev;
2197 unsigned char *addr;
2198 int err, reserve = 0;
2199 struct virtio_net_hdr vnet_hdr = { 0 };
2202 struct packet_sock *po = pkt_sk(sk);
2203 unsigned short gso_type = 0;
2206 * Get and verify the address.
2209 if (saddr == NULL) {
2210 dev = packet_cached_dev_get(po);
2215 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2217 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2219 proto = saddr->sll_protocol;
2220 addr = saddr->sll_addr;
2221 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2225 if (unlikely(dev == NULL))
2228 if (unlikely(!(dev->flags & IFF_UP)))
2231 if (sock->type == SOCK_RAW)
2232 reserve = dev->hard_header_len;
2233 if (po->has_vnet_hdr) {
2234 vnet_hdr_len = sizeof(vnet_hdr);
2237 if (len < vnet_hdr_len)
2240 len -= vnet_hdr_len;
2242 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2247 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2248 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2250 vnet_hdr.hdr_len = vnet_hdr.csum_start +
2251 vnet_hdr.csum_offset + 2;
2254 if (vnet_hdr.hdr_len > len)
2257 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2258 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2259 case VIRTIO_NET_HDR_GSO_TCPV4:
2260 gso_type = SKB_GSO_TCPV4;
2262 case VIRTIO_NET_HDR_GSO_TCPV6:
2263 gso_type = SKB_GSO_TCPV6;
2265 case VIRTIO_NET_HDR_GSO_UDP:
2266 gso_type = SKB_GSO_UDP;
2272 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2273 gso_type |= SKB_GSO_TCP_ECN;
2275 if (vnet_hdr.gso_size == 0)
2282 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
2286 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
2287 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
2288 msg->msg_flags & MSG_DONTWAIT, &err);
2292 skb_set_network_header(skb, reserve);
2295 if (sock->type == SOCK_DGRAM &&
2296 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2299 /* Returns -EFAULT on error */
2300 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2303 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2307 if (!gso_type && (len > dev->mtu + reserve)) {
2308 /* Earlier code assumed this would be a VLAN pkt,
2309 * double-check this now that we have the actual
2312 struct ethhdr *ehdr;
2313 skb_reset_mac_header(skb);
2314 ehdr = eth_hdr(skb);
2315 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2321 skb->protocol = proto;
2323 skb->priority = sk->sk_priority;
2324 skb->mark = sk->sk_mark;
2326 if (po->has_vnet_hdr) {
2327 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2328 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2329 vnet_hdr.csum_offset)) {
2335 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2336 skb_shinfo(skb)->gso_type = gso_type;
2338 /* Header must be checked, and gso_segs computed. */
2339 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2340 skb_shinfo(skb)->gso_segs = 0;
2342 len += vnet_hdr_len;
2349 err = dev_queue_xmit(skb);
2350 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2366 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2367 struct msghdr *msg, size_t len)
2369 struct sock *sk = sock->sk;
2370 struct packet_sock *po = pkt_sk(sk);
2371 if (po->tx_ring.pg_vec)
2372 return tpacket_snd(po, msg);
2374 return packet_snd(sock, msg, len);
2378 * Close a PACKET socket. This is fairly simple. We immediately go
2379 * to 'closed' state and remove our protocol entry in the device list.
2382 static int packet_release(struct socket *sock)
2384 struct sock *sk = sock->sk;
2385 struct packet_sock *po;
2387 union tpacket_req_u req_u;
2395 spin_lock_bh(&net->packet.sklist_lock);
2396 sk_del_node_init_rcu(sk);
2397 sock_prot_inuse_add(net, sk->sk_prot, -1);
2398 spin_unlock_bh(&net->packet.sklist_lock);
2400 spin_lock(&po->bind_lock);
2401 unregister_prot_hook(sk, false);
2402 if (po->prot_hook.dev) {
2403 dev_put(po->prot_hook.dev);
2404 po->prot_hook.dev = NULL;
2406 spin_unlock(&po->bind_lock);
2408 packet_flush_mclist(sk);
2410 if (po->rx_ring.pg_vec) {
2411 memset(&req_u, 0, sizeof(req_u));
2412 packet_set_ring(sk, &req_u, 1, 0);
2415 if (po->tx_ring.pg_vec) {
2416 memset(&req_u, 0, sizeof(req_u));
2417 packet_set_ring(sk, &req_u, 1, 1);
2424 * Now the socket is dead. No more input will appear.
2431 skb_queue_purge(&sk->sk_receive_queue);
2432 sk_refcnt_debug_release(sk);
2439 * Attach a packet hook.
2442 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2444 struct packet_sock *po = pkt_sk(sk);
2455 spin_lock(&po->bind_lock);
2456 unregister_prot_hook(sk, true);
2458 po->prot_hook.type = protocol;
2459 if (po->prot_hook.dev)
2460 dev_put(po->prot_hook.dev);
2461 po->prot_hook.dev = dev;
2463 po->ifindex = dev ? dev->ifindex : 0;
2468 if (!dev || (dev->flags & IFF_UP)) {
2469 register_prot_hook(sk);
2471 sk->sk_err = ENETDOWN;
2472 if (!sock_flag(sk, SOCK_DEAD))
2473 sk->sk_error_report(sk);
2477 spin_unlock(&po->bind_lock);
2483 * Bind a packet socket to a device
2486 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2489 struct sock *sk = sock->sk;
2491 struct net_device *dev;
2498 if (addr_len != sizeof(struct sockaddr))
2500 strlcpy(name, uaddr->sa_data, sizeof(name));
2502 dev = dev_get_by_name(sock_net(sk), name);
2504 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2508 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2510 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2511 struct sock *sk = sock->sk;
2512 struct net_device *dev = NULL;
2520 if (addr_len < sizeof(struct sockaddr_ll))
2522 if (sll->sll_family != AF_PACKET)
2525 if (sll->sll_ifindex) {
2527 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2531 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2537 static struct proto packet_proto = {
2539 .owner = THIS_MODULE,
2540 .obj_size = sizeof(struct packet_sock),
2544 * Create a packet of type SOCK_PACKET.
2547 static int packet_create(struct net *net, struct socket *sock, int protocol,
2551 struct packet_sock *po;
2552 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2555 if (!capable(CAP_NET_RAW))
2557 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2558 sock->type != SOCK_PACKET)
2559 return -ESOCKTNOSUPPORT;
2561 sock->state = SS_UNCONNECTED;
2564 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2568 sock->ops = &packet_ops;
2569 if (sock->type == SOCK_PACKET)
2570 sock->ops = &packet_ops_spkt;
2572 sock_init_data(sock, sk);
2575 sk->sk_family = PF_PACKET;
2577 RCU_INIT_POINTER(po->cached_dev, NULL);
2579 sk->sk_destruct = packet_sock_destruct;
2580 sk_refcnt_debug_inc(sk);
2583 * Attach a protocol block
2586 spin_lock_init(&po->bind_lock);
2587 mutex_init(&po->pg_vec_lock);
2588 po->prot_hook.func = packet_rcv;
2590 if (sock->type == SOCK_PACKET)
2591 po->prot_hook.func = packet_rcv_spkt;
2593 po->prot_hook.af_packet_priv = sk;
2596 po->prot_hook.type = proto;
2597 register_prot_hook(sk);
2600 spin_lock_bh(&net->packet.sklist_lock);
2601 sk_add_node_rcu(sk, &net->packet.sklist);
2602 sock_prot_inuse_add(net, &packet_proto, 1);
2603 spin_unlock_bh(&net->packet.sklist_lock);
2610 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2612 struct sock_exterr_skb *serr;
2613 struct sk_buff *skb, *skb2;
2617 skb = skb_dequeue(&sk->sk_error_queue);
2623 msg->msg_flags |= MSG_TRUNC;
2626 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2630 sock_recv_timestamp(msg, sk, skb);
2632 serr = SKB_EXT_ERR(skb);
2633 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2634 sizeof(serr->ee), &serr->ee);
2636 msg->msg_flags |= MSG_ERRQUEUE;
2639 /* Reset and regenerate socket error */
2640 spin_lock_bh(&sk->sk_error_queue.lock);
2642 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2643 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2644 spin_unlock_bh(&sk->sk_error_queue.lock);
2645 sk->sk_error_report(sk);
2647 spin_unlock_bh(&sk->sk_error_queue.lock);
2656 * Pull a packet from our receive queue and hand it to the user.
2657 * If necessary we block.
2660 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2661 struct msghdr *msg, size_t len, int flags)
2663 struct sock *sk = sock->sk;
2664 struct sk_buff *skb;
2666 int vnet_hdr_len = 0;
2669 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2673 /* What error should we return now? EUNATTACH? */
2674 if (pkt_sk(sk)->ifindex < 0)
2678 if (flags & MSG_ERRQUEUE) {
2679 err = packet_recv_error(sk, msg, len);
2684 * Call the generic datagram receiver. This handles all sorts
2685 * of horrible races and re-entrancy so we can forget about it
2686 * in the protocol layers.
2688 * Now it will return ENETDOWN, if device have just gone down,
2689 * but then it will block.
2692 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2695 * An error occurred so return it. Because skb_recv_datagram()
2696 * handles the blocking we don't see and worry about blocking
2703 if (pkt_sk(sk)->has_vnet_hdr) {
2704 struct virtio_net_hdr vnet_hdr = { 0 };
2707 vnet_hdr_len = sizeof(vnet_hdr);
2708 if (len < vnet_hdr_len)
2711 len -= vnet_hdr_len;
2713 if (skb_is_gso(skb)) {
2714 struct skb_shared_info *sinfo = skb_shinfo(skb);
2716 /* This is a hint as to how much should be linear. */
2717 vnet_hdr.hdr_len = skb_headlen(skb);
2718 vnet_hdr.gso_size = sinfo->gso_size;
2719 if (sinfo->gso_type & SKB_GSO_TCPV4)
2720 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2721 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2722 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2723 else if (sinfo->gso_type & SKB_GSO_UDP)
2724 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2725 else if (sinfo->gso_type & SKB_GSO_FCOE)
2729 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2730 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2732 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2734 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2735 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2736 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2737 vnet_hdr.csum_offset = skb->csum_offset;
2738 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2739 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2740 } /* else everything is zero */
2742 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2748 /* You lose any data beyond the buffer you gave. If it worries
2749 * a user program they can ask the device for its MTU
2755 msg->msg_flags |= MSG_TRUNC;
2758 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2762 sock_recv_ts_and_drops(msg, sk, skb);
2764 if (msg->msg_name) {
2765 /* If the address length field is there to be filled
2766 * in, we fill it in now.
2768 if (sock->type == SOCK_PACKET) {
2769 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2771 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2772 msg->msg_namelen = sll->sll_halen +
2773 offsetof(struct sockaddr_ll, sll_addr);
2775 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2779 if (pkt_sk(sk)->auxdata) {
2780 struct tpacket_auxdata aux;
2782 aux.tp_status = TP_STATUS_USER;
2783 if (skb->ip_summed == CHECKSUM_PARTIAL)
2784 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2785 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2786 aux.tp_snaplen = skb->len;
2788 aux.tp_net = skb_network_offset(skb);
2789 if (vlan_tx_tag_present(skb)) {
2790 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2791 aux.tp_status |= TP_STATUS_VLAN_VALID;
2793 aux.tp_vlan_tci = 0;
2796 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2800 * Free or return the buffer as appropriate. Again this
2801 * hides all the races and re-entrancy issues from us.
2803 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2806 skb_free_datagram(sk, skb);
2811 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2812 int *uaddr_len, int peer)
2814 struct net_device *dev;
2815 struct sock *sk = sock->sk;
2820 uaddr->sa_family = AF_PACKET;
2821 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
2823 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2825 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
2827 *uaddr_len = sizeof(*uaddr);
2832 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2833 int *uaddr_len, int peer)
2835 struct net_device *dev;
2836 struct sock *sk = sock->sk;
2837 struct packet_sock *po = pkt_sk(sk);
2838 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2843 sll->sll_family = AF_PACKET;
2844 sll->sll_ifindex = po->ifindex;
2845 sll->sll_protocol = po->num;
2846 sll->sll_pkttype = 0;
2848 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2850 sll->sll_hatype = dev->type;
2851 sll->sll_halen = dev->addr_len;
2852 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2854 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2858 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2863 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2867 case PACKET_MR_MULTICAST:
2868 if (i->alen != dev->addr_len)
2871 return dev_mc_add(dev, i->addr);
2873 return dev_mc_del(dev, i->addr);
2875 case PACKET_MR_PROMISC:
2876 return dev_set_promiscuity(dev, what);
2878 case PACKET_MR_ALLMULTI:
2879 return dev_set_allmulti(dev, what);
2881 case PACKET_MR_UNICAST:
2882 if (i->alen != dev->addr_len)
2885 return dev_uc_add(dev, i->addr);
2887 return dev_uc_del(dev, i->addr);
2895 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2897 for ( ; i; i = i->next) {
2898 if (i->ifindex == dev->ifindex)
2899 packet_dev_mc(dev, i, what);
2903 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2905 struct packet_sock *po = pkt_sk(sk);
2906 struct packet_mclist *ml, *i;
2907 struct net_device *dev;
2913 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2918 if (mreq->mr_alen > dev->addr_len)
2922 i = kmalloc(sizeof(*i), GFP_KERNEL);
2927 for (ml = po->mclist; ml; ml = ml->next) {
2928 if (ml->ifindex == mreq->mr_ifindex &&
2929 ml->type == mreq->mr_type &&
2930 ml->alen == mreq->mr_alen &&
2931 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2933 /* Free the new element ... */
2939 i->type = mreq->mr_type;
2940 i->ifindex = mreq->mr_ifindex;
2941 i->alen = mreq->mr_alen;
2942 memcpy(i->addr, mreq->mr_address, i->alen);
2944 i->next = po->mclist;
2946 err = packet_dev_mc(dev, i, 1);
2948 po->mclist = i->next;
2957 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2959 struct packet_mclist *ml, **mlp;
2963 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2964 if (ml->ifindex == mreq->mr_ifindex &&
2965 ml->type == mreq->mr_type &&
2966 ml->alen == mreq->mr_alen &&
2967 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2968 if (--ml->count == 0) {
2969 struct net_device *dev;
2971 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2973 packet_dev_mc(dev, ml, -1);
2981 return -EADDRNOTAVAIL;
2984 static void packet_flush_mclist(struct sock *sk)
2986 struct packet_sock *po = pkt_sk(sk);
2987 struct packet_mclist *ml;
2993 while ((ml = po->mclist) != NULL) {
2994 struct net_device *dev;
2996 po->mclist = ml->next;
2997 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2999 packet_dev_mc(dev, ml, -1);
3006 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3008 struct sock *sk = sock->sk;
3009 struct packet_sock *po = pkt_sk(sk);
3012 if (level != SOL_PACKET)
3013 return -ENOPROTOOPT;
3016 case PACKET_ADD_MEMBERSHIP:
3017 case PACKET_DROP_MEMBERSHIP:
3019 struct packet_mreq_max mreq;
3021 memset(&mreq, 0, sizeof(mreq));
3022 if (len < sizeof(struct packet_mreq))
3024 if (len > sizeof(mreq))
3026 if (copy_from_user(&mreq, optval, len))
3028 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3030 if (optname == PACKET_ADD_MEMBERSHIP)
3031 ret = packet_mc_add(sk, &mreq);
3033 ret = packet_mc_drop(sk, &mreq);
3037 case PACKET_RX_RING:
3038 case PACKET_TX_RING:
3040 union tpacket_req_u req_u;
3043 switch (po->tp_version) {
3046 len = sizeof(req_u.req);
3050 len = sizeof(req_u.req3);
3055 if (pkt_sk(sk)->has_vnet_hdr)
3057 if (copy_from_user(&req_u.req, optval, len))
3059 return packet_set_ring(sk, &req_u, 0,
3060 optname == PACKET_TX_RING);
3062 case PACKET_COPY_THRESH:
3066 if (optlen != sizeof(val))
3068 if (copy_from_user(&val, optval, sizeof(val)))
3071 pkt_sk(sk)->copy_thresh = val;
3074 case PACKET_VERSION:
3078 if (optlen != sizeof(val))
3080 if (copy_from_user(&val, optval, sizeof(val)))
3091 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3094 po->tp_version = val;
3100 case PACKET_RESERVE:
3104 if (optlen != sizeof(val))
3106 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3108 if (copy_from_user(&val, optval, sizeof(val)))
3110 po->tp_reserve = val;
3117 if (optlen != sizeof(val))
3119 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3121 if (copy_from_user(&val, optval, sizeof(val)))
3123 po->tp_loss = !!val;
3126 case PACKET_AUXDATA:
3130 if (optlen < sizeof(val))
3132 if (copy_from_user(&val, optval, sizeof(val)))
3135 po->auxdata = !!val;
3138 case PACKET_ORIGDEV:
3142 if (optlen < sizeof(val))
3144 if (copy_from_user(&val, optval, sizeof(val)))
3147 po->origdev = !!val;
3150 case PACKET_VNET_HDR:
3154 if (sock->type != SOCK_RAW)
3156 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3158 if (optlen < sizeof(val))
3160 if (copy_from_user(&val, optval, sizeof(val)))
3163 po->has_vnet_hdr = !!val;
3166 case PACKET_TIMESTAMP:
3170 if (optlen != sizeof(val))
3172 if (copy_from_user(&val, optval, sizeof(val)))
3175 po->tp_tstamp = val;
3182 if (optlen != sizeof(val))
3184 if (copy_from_user(&val, optval, sizeof(val)))
3187 return fanout_add(sk, val & 0xffff, val >> 16);
3190 return -ENOPROTOOPT;
3194 static int packet_getsockopt(struct socket *sock, int level, int optname,
3195 char __user *optval, int __user *optlen)
3199 struct sock *sk = sock->sk;
3200 struct packet_sock *po = pkt_sk(sk);
3202 struct tpacket_stats st;
3203 union tpacket_stats_u st_u;
3205 if (level != SOL_PACKET)
3206 return -ENOPROTOOPT;
3208 if (get_user(len, optlen))
3215 case PACKET_STATISTICS:
3216 if (po->tp_version == TPACKET_V3) {
3217 len = sizeof(struct tpacket_stats_v3);
3219 if (len > sizeof(struct tpacket_stats))
3220 len = sizeof(struct tpacket_stats);
3222 spin_lock_bh(&sk->sk_receive_queue.lock);
3223 if (po->tp_version == TPACKET_V3) {
3224 memcpy(&st_u.stats3, &po->stats,
3225 sizeof(struct tpacket_stats));
3226 st_u.stats3.tp_freeze_q_cnt =
3227 po->stats_u.stats3.tp_freeze_q_cnt;
3228 st_u.stats3.tp_packets += po->stats.tp_drops;
3229 data = &st_u.stats3;
3232 st.tp_packets += st.tp_drops;
3235 memset(&po->stats, 0, sizeof(st));
3236 spin_unlock_bh(&sk->sk_receive_queue.lock);
3238 case PACKET_AUXDATA:
3239 if (len > sizeof(int))
3245 case PACKET_ORIGDEV:
3246 if (len > sizeof(int))
3252 case PACKET_VNET_HDR:
3253 if (len > sizeof(int))
3255 val = po->has_vnet_hdr;
3259 case PACKET_VERSION:
3260 if (len > sizeof(int))
3262 val = po->tp_version;
3266 if (len > sizeof(int))
3268 if (copy_from_user(&val, optval, len))
3272 val = sizeof(struct tpacket_hdr);
3275 val = sizeof(struct tpacket2_hdr);
3278 val = sizeof(struct tpacket3_hdr);
3285 case PACKET_RESERVE:
3286 if (len > sizeof(unsigned int))
3287 len = sizeof(unsigned int);
3288 val = po->tp_reserve;
3292 if (len > sizeof(unsigned int))
3293 len = sizeof(unsigned int);
3297 case PACKET_TIMESTAMP:
3298 if (len > sizeof(int))
3300 val = po->tp_tstamp;
3304 if (len > sizeof(int))
3307 ((u32)po->fanout->id |
3308 ((u32)po->fanout->type << 16)) :
3313 return -ENOPROTOOPT;
3316 if (put_user(len, optlen))
3318 if (copy_to_user(optval, data, len))
3324 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3327 struct hlist_node *node;
3328 struct net_device *dev = data;
3329 struct net *net = dev_net(dev);
3332 sk_for_each_rcu(sk, node, &net->packet.sklist) {
3333 struct packet_sock *po = pkt_sk(sk);
3336 case NETDEV_UNREGISTER:
3338 packet_dev_mclist(dev, po->mclist, -1);
3342 if (dev->ifindex == po->ifindex) {
3343 spin_lock(&po->bind_lock);
3345 __unregister_prot_hook(sk, false);
3346 sk->sk_err = ENETDOWN;
3347 if (!sock_flag(sk, SOCK_DEAD))
3348 sk->sk_error_report(sk);
3350 if (msg == NETDEV_UNREGISTER) {
3352 if (po->prot_hook.dev)
3353 dev_put(po->prot_hook.dev);
3354 po->prot_hook.dev = NULL;
3356 spin_unlock(&po->bind_lock);
3360 if (dev->ifindex == po->ifindex) {
3361 spin_lock(&po->bind_lock);
3363 register_prot_hook(sk);
3364 spin_unlock(&po->bind_lock);
3374 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3377 struct sock *sk = sock->sk;
3382 int amount = sk_wmem_alloc_get(sk);
3384 return put_user(amount, (int __user *)arg);
3388 struct sk_buff *skb;
3391 spin_lock_bh(&sk->sk_receive_queue.lock);
3392 skb = skb_peek(&sk->sk_receive_queue);
3395 spin_unlock_bh(&sk->sk_receive_queue.lock);
3396 return put_user(amount, (int __user *)arg);
3399 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3401 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3411 case SIOCGIFBRDADDR:
3412 case SIOCSIFBRDADDR:
3413 case SIOCGIFNETMASK:
3414 case SIOCSIFNETMASK:
3415 case SIOCGIFDSTADDR:
3416 case SIOCSIFDSTADDR:
3418 return inet_dgram_ops.ioctl(sock, cmd, arg);
3422 return -ENOIOCTLCMD;
3427 static unsigned int packet_poll(struct file *file, struct socket *sock,
3430 struct sock *sk = sock->sk;
3431 struct packet_sock *po = pkt_sk(sk);
3432 unsigned int mask = datagram_poll(file, sock, wait);
3434 spin_lock_bh(&sk->sk_receive_queue.lock);
3435 if (po->rx_ring.pg_vec) {
3436 if (!packet_previous_rx_frame(po, &po->rx_ring,
3438 mask |= POLLIN | POLLRDNORM;
3440 spin_unlock_bh(&sk->sk_receive_queue.lock);
3441 spin_lock_bh(&sk->sk_write_queue.lock);
3442 if (po->tx_ring.pg_vec) {
3443 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3444 mask |= POLLOUT | POLLWRNORM;
3446 spin_unlock_bh(&sk->sk_write_queue.lock);
3451 /* Dirty? Well, I still did not learn better way to account
3455 static void packet_mm_open(struct vm_area_struct *vma)
3457 struct file *file = vma->vm_file;
3458 struct socket *sock = file->private_data;
3459 struct sock *sk = sock->sk;
3462 atomic_inc(&pkt_sk(sk)->mapped);
3465 static void packet_mm_close(struct vm_area_struct *vma)
3467 struct file *file = vma->vm_file;
3468 struct socket *sock = file->private_data;
3469 struct sock *sk = sock->sk;
3472 atomic_dec(&pkt_sk(sk)->mapped);
3475 static const struct vm_operations_struct packet_mmap_ops = {
3476 .open = packet_mm_open,
3477 .close = packet_mm_close,
3480 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3485 for (i = 0; i < len; i++) {
3486 if (likely(pg_vec[i].buffer)) {
3487 if (is_vmalloc_addr(pg_vec[i].buffer))
3488 vfree(pg_vec[i].buffer);
3490 free_pages((unsigned long)pg_vec[i].buffer,
3492 pg_vec[i].buffer = NULL;
3498 static char *alloc_one_pg_vec_page(unsigned long order)
3500 char *buffer = NULL;
3501 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3502 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3504 buffer = (char *) __get_free_pages(gfp_flags, order);
3510 * __get_free_pages failed, fall back to vmalloc
3512 buffer = vzalloc((1 << order) * PAGE_SIZE);
3518 * vmalloc failed, lets dig into swap here
3520 gfp_flags &= ~__GFP_NORETRY;
3521 buffer = (char *)__get_free_pages(gfp_flags, order);
3526 * complete and utter failure
3531 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3533 unsigned int block_nr = req->tp_block_nr;
3537 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3538 if (unlikely(!pg_vec))
3541 for (i = 0; i < block_nr; i++) {
3542 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3543 if (unlikely(!pg_vec[i].buffer))
3544 goto out_free_pgvec;
3551 free_pg_vec(pg_vec, order, block_nr);
3556 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3557 int closing, int tx_ring)
3559 struct pgv *pg_vec = NULL;
3560 struct packet_sock *po = pkt_sk(sk);
3561 int was_running, order = 0;
3562 struct packet_ring_buffer *rb;
3563 struct sk_buff_head *rb_queue;
3566 /* Added to avoid minimal code churn */
3567 struct tpacket_req *req = &req_u->req;
3570 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3571 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3572 WARN(1, "Tx-ring is not supported.\n");
3576 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3577 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3581 if (atomic_read(&po->mapped))
3583 if (atomic_read(&rb->pending))
3587 if (req->tp_block_nr) {
3588 /* Sanity tests and some calculations */
3590 if (unlikely(rb->pg_vec))
3593 switch (po->tp_version) {
3595 po->tp_hdrlen = TPACKET_HDRLEN;
3598 po->tp_hdrlen = TPACKET2_HDRLEN;
3601 po->tp_hdrlen = TPACKET3_HDRLEN;
3606 if (unlikely((int)req->tp_block_size <= 0))
3608 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3610 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3613 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3616 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3617 if (unlikely(rb->frames_per_block <= 0))
3619 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3624 order = get_order(req->tp_block_size);
3625 pg_vec = alloc_pg_vec(req, order);
3626 if (unlikely(!pg_vec))
3628 switch (po->tp_version) {
3630 /* Transmit path is not supported. We checked
3631 * it above but just being paranoid
3634 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3643 if (unlikely(req->tp_frame_nr))
3648 /* Detach socket from network */
3649 spin_lock(&po->bind_lock);
3650 was_running = po->running;
3654 __unregister_prot_hook(sk, false);
3656 spin_unlock(&po->bind_lock);
3661 mutex_lock(&po->pg_vec_lock);
3662 if (closing || atomic_read(&po->mapped) == 0) {
3664 spin_lock_bh(&rb_queue->lock);
3665 swap(rb->pg_vec, pg_vec);
3666 rb->frame_max = (req->tp_frame_nr - 1);
3668 rb->frame_size = req->tp_frame_size;
3669 spin_unlock_bh(&rb_queue->lock);
3671 swap(rb->pg_vec_order, order);
3672 swap(rb->pg_vec_len, req->tp_block_nr);
3674 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3675 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3676 tpacket_rcv : packet_rcv;
3677 skb_queue_purge(rb_queue);
3678 if (atomic_read(&po->mapped))
3679 pr_err("packet_mmap: vma is busy: %d\n",
3680 atomic_read(&po->mapped));
3682 mutex_unlock(&po->pg_vec_lock);
3684 spin_lock(&po->bind_lock);
3687 register_prot_hook(sk);
3689 spin_unlock(&po->bind_lock);
3690 if (closing && (po->tp_version > TPACKET_V2)) {
3691 /* Because we don't support block-based V3 on tx-ring */
3693 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3697 free_pg_vec(pg_vec, order, req->tp_block_nr);
3703 static int packet_mmap(struct file *file, struct socket *sock,
3704 struct vm_area_struct *vma)
3706 struct sock *sk = sock->sk;
3707 struct packet_sock *po = pkt_sk(sk);
3708 unsigned long size, expected_size;
3709 struct packet_ring_buffer *rb;
3710 unsigned long start;
3717 mutex_lock(&po->pg_vec_lock);
3720 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3722 expected_size += rb->pg_vec_len
3728 if (expected_size == 0)
3731 size = vma->vm_end - vma->vm_start;
3732 if (size != expected_size)
3735 start = vma->vm_start;
3736 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3737 if (rb->pg_vec == NULL)
3740 for (i = 0; i < rb->pg_vec_len; i++) {
3742 void *kaddr = rb->pg_vec[i].buffer;
3745 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3746 page = pgv_to_page(kaddr);
3747 err = vm_insert_page(vma, start, page);
3756 atomic_inc(&po->mapped);
3757 vma->vm_ops = &packet_mmap_ops;
3761 mutex_unlock(&po->pg_vec_lock);
3765 static const struct proto_ops packet_ops_spkt = {
3766 .family = PF_PACKET,
3767 .owner = THIS_MODULE,
3768 .release = packet_release,
3769 .bind = packet_bind_spkt,
3770 .connect = sock_no_connect,
3771 .socketpair = sock_no_socketpair,
3772 .accept = sock_no_accept,
3773 .getname = packet_getname_spkt,
3774 .poll = datagram_poll,
3775 .ioctl = packet_ioctl,
3776 .listen = sock_no_listen,
3777 .shutdown = sock_no_shutdown,
3778 .setsockopt = sock_no_setsockopt,
3779 .getsockopt = sock_no_getsockopt,
3780 .sendmsg = packet_sendmsg_spkt,
3781 .recvmsg = packet_recvmsg,
3782 .mmap = sock_no_mmap,
3783 .sendpage = sock_no_sendpage,
3786 static const struct proto_ops packet_ops = {
3787 .family = PF_PACKET,
3788 .owner = THIS_MODULE,
3789 .release = packet_release,
3790 .bind = packet_bind,
3791 .connect = sock_no_connect,
3792 .socketpair = sock_no_socketpair,
3793 .accept = sock_no_accept,
3794 .getname = packet_getname,
3795 .poll = packet_poll,
3796 .ioctl = packet_ioctl,
3797 .listen = sock_no_listen,
3798 .shutdown = sock_no_shutdown,
3799 .setsockopt = packet_setsockopt,
3800 .getsockopt = packet_getsockopt,
3801 .sendmsg = packet_sendmsg,
3802 .recvmsg = packet_recvmsg,
3803 .mmap = packet_mmap,
3804 .sendpage = sock_no_sendpage,
3807 static const struct net_proto_family packet_family_ops = {
3808 .family = PF_PACKET,
3809 .create = packet_create,
3810 .owner = THIS_MODULE,
3813 static struct notifier_block packet_netdev_notifier = {
3814 .notifier_call = packet_notifier,
3817 #ifdef CONFIG_PROC_FS
3819 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3822 struct net *net = seq_file_net(seq);
3825 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3828 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3830 struct net *net = seq_file_net(seq);
3831 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3834 static void packet_seq_stop(struct seq_file *seq, void *v)
3840 static int packet_seq_show(struct seq_file *seq, void *v)
3842 if (v == SEQ_START_TOKEN)
3843 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3845 struct sock *s = sk_entry(v);
3846 const struct packet_sock *po = pkt_sk(s);
3849 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3851 atomic_read(&s->sk_refcnt),
3856 atomic_read(&s->sk_rmem_alloc),
3864 static const struct seq_operations packet_seq_ops = {
3865 .start = packet_seq_start,
3866 .next = packet_seq_next,
3867 .stop = packet_seq_stop,
3868 .show = packet_seq_show,
3871 static int packet_seq_open(struct inode *inode, struct file *file)
3873 return seq_open_net(inode, file, &packet_seq_ops,
3874 sizeof(struct seq_net_private));
3877 static const struct file_operations packet_seq_fops = {
3878 .owner = THIS_MODULE,
3879 .open = packet_seq_open,
3881 .llseek = seq_lseek,
3882 .release = seq_release_net,
3887 static int __net_init packet_net_init(struct net *net)
3889 spin_lock_init(&net->packet.sklist_lock);
3890 INIT_HLIST_HEAD(&net->packet.sklist);
3892 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
3898 static void __net_exit packet_net_exit(struct net *net)
3900 proc_net_remove(net, "packet");
3903 static struct pernet_operations packet_net_ops = {
3904 .init = packet_net_init,
3905 .exit = packet_net_exit,
3909 static void __exit packet_exit(void)
3911 unregister_netdevice_notifier(&packet_netdev_notifier);
3912 unregister_pernet_subsys(&packet_net_ops);
3913 sock_unregister(PF_PACKET);
3914 proto_unregister(&packet_proto);
3917 static int __init packet_init(void)
3919 int rc = proto_register(&packet_proto, 0);
3924 sock_register(&packet_family_ops);
3925 register_pernet_subsys(&packet_net_ops);
3926 register_netdevice_notifier(&packet_netdev_notifier);
3931 module_init(packet_init);
3932 module_exit(packet_exit);
3933 MODULE_LICENSE("GPL");
3934 MODULE_ALIAS_NETPROTO(PF_PACKET);