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/uaccess.h>
77 #include <asm/ioctls.h>
79 #include <asm/cacheflush.h>
81 #include <linux/proc_fs.h>
82 #include <linux/seq_file.h>
83 #include <linux/poll.h>
84 #include <linux/module.h>
85 #include <linux/init.h>
86 #include <linux/mutex.h>
87 #include <linux/if_vlan.h>
88 #include <linux/virtio_net.h>
89 #include <linux/errqueue.h>
90 #include <linux/net_tstamp.h>
93 #include <net/inet_common.h>
100 - if device has no dev->hard_header routine, it adds and removes ll header
101 inside itself. In this case ll header is invisible outside of device,
102 but higher levels still should reserve dev->hard_header_len.
103 Some devices are enough clever to reallocate skb, when header
104 will not fit to reserved space (tunnel), another ones are silly
106 - packet socket receives packets with pulled ll header,
107 so that SOCK_RAW should push it back.
112 Incoming, dev->hard_header!=NULL
113 mac_header -> ll header
116 Outgoing, dev->hard_header!=NULL
117 mac_header -> ll header
120 Incoming, dev->hard_header==NULL
121 mac_header -> UNKNOWN position. It is very likely, that it points to ll
122 header. PPP makes it, that is wrong, because introduce
123 assymetry between rx and tx paths.
126 Outgoing, dev->hard_header==NULL
127 mac_header -> data. ll header is still not built!
131 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
137 dev->hard_header != NULL
138 mac_header -> ll header
141 dev->hard_header == NULL (ll header is added by device, we cannot control it)
145 We should set nh.raw on output to correct posistion,
146 packet classifier depends on it.
149 /* Private packet socket structures. */
151 /* identical to struct packet_mreq except it has
152 * a longer address field.
154 struct packet_mreq_max {
156 unsigned short mr_type;
157 unsigned short mr_alen;
158 unsigned char mr_address[MAX_ADDR_LEN];
161 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
162 int closing, int tx_ring);
165 #define V3_ALIGNMENT (8)
167 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
169 #define BLK_PLUS_PRIV(sz_of_priv) \
170 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
172 #define PGV_FROM_VMALLOC 1
174 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
175 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
176 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
177 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
178 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
179 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
180 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
183 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
184 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
185 struct packet_type *pt, struct net_device *orig_dev);
187 static void *packet_previous_frame(struct packet_sock *po,
188 struct packet_ring_buffer *rb,
190 static void packet_increment_head(struct packet_ring_buffer *buff);
191 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
192 struct tpacket_block_desc *);
193 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
194 struct packet_sock *);
195 static void prb_retire_current_block(struct tpacket_kbdq_core *,
196 struct packet_sock *, unsigned int status);
197 static int prb_queue_frozen(struct tpacket_kbdq_core *);
198 static void prb_open_block(struct tpacket_kbdq_core *,
199 struct tpacket_block_desc *);
200 static void prb_retire_rx_blk_timer_expired(unsigned long);
201 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
202 static void prb_init_blk_timer(struct packet_sock *,
203 struct tpacket_kbdq_core *,
204 void (*func) (unsigned long));
205 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
206 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
207 struct tpacket3_hdr *);
208 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
209 struct tpacket3_hdr *);
210 static void packet_flush_mclist(struct sock *sk);
212 struct packet_skb_cb {
213 unsigned int origlen;
215 struct sockaddr_pkt pkt;
216 struct sockaddr_ll ll;
220 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
222 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
223 #define GET_PBLOCK_DESC(x, bid) \
224 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
225 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
226 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
227 #define GET_NEXT_PRB_BLK_NUM(x) \
228 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
229 ((x)->kactive_blk_num+1) : 0)
231 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
232 static void __fanout_link(struct sock *sk, struct packet_sock *po);
234 /* register_prot_hook must be invoked with the po->bind_lock held,
235 * or from a context in which asynchronous accesses to the packet
236 * socket is not possible (packet_create()).
238 static void register_prot_hook(struct sock *sk)
240 struct packet_sock *po = pkt_sk(sk);
243 __fanout_link(sk, po);
245 dev_add_pack(&po->prot_hook);
251 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
252 * held. If the sync parameter is true, we will temporarily drop
253 * the po->bind_lock and do a synchronize_net to make sure no
254 * asynchronous packet processing paths still refer to the elements
255 * of po->prot_hook. If the sync parameter is false, it is the
256 * callers responsibility to take care of this.
258 static void __unregister_prot_hook(struct sock *sk, bool sync)
260 struct packet_sock *po = pkt_sk(sk);
264 __fanout_unlink(sk, po);
266 __dev_remove_pack(&po->prot_hook);
270 spin_unlock(&po->bind_lock);
272 spin_lock(&po->bind_lock);
276 static void unregister_prot_hook(struct sock *sk, bool sync)
278 struct packet_sock *po = pkt_sk(sk);
281 __unregister_prot_hook(sk, sync);
284 static inline __pure struct page *pgv_to_page(void *addr)
286 if (is_vmalloc_addr(addr))
287 return vmalloc_to_page(addr);
288 return virt_to_page(addr);
291 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
294 struct tpacket_hdr *h1;
295 struct tpacket2_hdr *h2;
300 switch (po->tp_version) {
302 h.h1->tp_status = status;
303 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
306 h.h2->tp_status = status;
307 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
311 WARN(1, "TPACKET version not supported.\n");
318 static int __packet_get_status(struct packet_sock *po, void *frame)
321 struct tpacket_hdr *h1;
322 struct tpacket2_hdr *h2;
329 switch (po->tp_version) {
331 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
332 return h.h1->tp_status;
334 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
335 return h.h2->tp_status;
338 WARN(1, "TPACKET version not supported.\n");
344 static void *packet_lookup_frame(struct packet_sock *po,
345 struct packet_ring_buffer *rb,
346 unsigned int position,
349 unsigned int pg_vec_pos, frame_offset;
351 struct tpacket_hdr *h1;
352 struct tpacket2_hdr *h2;
356 pg_vec_pos = position / rb->frames_per_block;
357 frame_offset = position % rb->frames_per_block;
359 h.raw = rb->pg_vec[pg_vec_pos].buffer +
360 (frame_offset * rb->frame_size);
362 if (status != __packet_get_status(po, h.raw))
368 static void *packet_current_frame(struct packet_sock *po,
369 struct packet_ring_buffer *rb,
372 return packet_lookup_frame(po, rb, rb->head, status);
375 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
377 del_timer_sync(&pkc->retire_blk_timer);
380 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
382 struct sk_buff_head *rb_queue)
384 struct tpacket_kbdq_core *pkc;
386 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
388 spin_lock(&rb_queue->lock);
389 pkc->delete_blk_timer = 1;
390 spin_unlock(&rb_queue->lock);
392 prb_del_retire_blk_timer(pkc);
395 static void prb_init_blk_timer(struct packet_sock *po,
396 struct tpacket_kbdq_core *pkc,
397 void (*func) (unsigned long))
399 init_timer(&pkc->retire_blk_timer);
400 pkc->retire_blk_timer.data = (long)po;
401 pkc->retire_blk_timer.function = func;
402 pkc->retire_blk_timer.expires = jiffies;
405 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
407 struct tpacket_kbdq_core *pkc;
412 pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
413 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
416 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
417 int blk_size_in_bytes)
419 struct net_device *dev;
420 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
421 struct ethtool_cmd ecmd;
426 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
427 if (unlikely(!dev)) {
429 return DEFAULT_PRB_RETIRE_TOV;
431 err = __ethtool_get_settings(dev, &ecmd);
432 speed = ethtool_cmd_speed(&ecmd);
436 * If the link speed is so slow you don't really
437 * need to worry about perf anyways
439 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
440 return DEFAULT_PRB_RETIRE_TOV;
447 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
459 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
460 union tpacket_req_u *req_u)
462 p1->feature_req_word = req_u->req3.tp_feature_req_word;
465 static void init_prb_bdqc(struct packet_sock *po,
466 struct packet_ring_buffer *rb,
468 union tpacket_req_u *req_u, int tx_ring)
470 struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
471 struct tpacket_block_desc *pbd;
473 memset(p1, 0x0, sizeof(*p1));
475 p1->knxt_seq_num = 1;
477 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
478 p1->pkblk_start = pg_vec[0].buffer;
479 p1->kblk_size = req_u->req3.tp_block_size;
480 p1->knum_blocks = req_u->req3.tp_block_nr;
481 p1->hdrlen = po->tp_hdrlen;
482 p1->version = po->tp_version;
483 p1->last_kactive_blk_num = 0;
484 po->stats_u.stats3.tp_freeze_q_cnt = 0;
485 if (req_u->req3.tp_retire_blk_tov)
486 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
488 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
489 req_u->req3.tp_block_size);
490 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
491 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
493 prb_init_ft_ops(p1, req_u);
494 prb_setup_retire_blk_timer(po, tx_ring);
495 prb_open_block(p1, pbd);
498 /* Do NOT update the last_blk_num first.
499 * Assumes sk_buff_head lock is held.
501 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
503 mod_timer(&pkc->retire_blk_timer,
504 jiffies + pkc->tov_in_jiffies);
505 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
510 * 1) We refresh the timer only when we open a block.
511 * By doing this we don't waste cycles refreshing the timer
512 * on packet-by-packet basis.
514 * With a 1MB block-size, on a 1Gbps line, it will take
515 * i) ~8 ms to fill a block + ii) memcpy etc.
516 * In this cut we are not accounting for the memcpy time.
518 * So, if the user sets the 'tmo' to 10ms then the timer
519 * will never fire while the block is still getting filled
520 * (which is what we want). However, the user could choose
521 * to close a block early and that's fine.
523 * But when the timer does fire, we check whether or not to refresh it.
524 * Since the tmo granularity is in msecs, it is not too expensive
525 * to refresh the timer, lets say every '8' msecs.
526 * Either the user can set the 'tmo' or we can derive it based on
527 * a) line-speed and b) block-size.
528 * prb_calc_retire_blk_tmo() calculates the tmo.
531 static void prb_retire_rx_blk_timer_expired(unsigned long data)
533 struct packet_sock *po = (struct packet_sock *)data;
534 struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
536 struct tpacket_block_desc *pbd;
538 spin_lock(&po->sk.sk_receive_queue.lock);
540 frozen = prb_queue_frozen(pkc);
541 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
543 if (unlikely(pkc->delete_blk_timer))
546 /* We only need to plug the race when the block is partially filled.
548 * lock(); increment BLOCK_NUM_PKTS; unlock()
549 * copy_bits() is in progress ...
550 * timer fires on other cpu:
551 * we can't retire the current block because copy_bits
555 if (BLOCK_NUM_PKTS(pbd)) {
556 while (atomic_read(&pkc->blk_fill_in_prog)) {
557 /* Waiting for skb_copy_bits to finish... */
562 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
564 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
565 if (!prb_dispatch_next_block(pkc, po))
570 /* Case 1. Queue was frozen because user-space was
573 if (prb_curr_blk_in_use(pkc, pbd)) {
575 * Ok, user-space is still behind.
576 * So just refresh the timer.
580 /* Case 2. queue was frozen,user-space caught up,
581 * now the link went idle && the timer fired.
582 * We don't have a block to close.So we open this
583 * block and restart the timer.
584 * opening a block thaws the queue,restarts timer
585 * Thawing/timer-refresh is a side effect.
587 prb_open_block(pkc, pbd);
594 _prb_refresh_rx_retire_blk_timer(pkc);
597 spin_unlock(&po->sk.sk_receive_queue.lock);
600 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
601 struct tpacket_block_desc *pbd1, __u32 status)
603 /* Flush everything minus the block header */
605 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
610 /* Skip the block header(we know header WILL fit in 4K) */
613 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
614 for (; start < end; start += PAGE_SIZE)
615 flush_dcache_page(pgv_to_page(start));
620 /* Now update the block status. */
622 BLOCK_STATUS(pbd1) = status;
624 /* Flush the block header */
626 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
628 flush_dcache_page(pgv_to_page(start));
638 * 2) Increment active_blk_num
640 * Note:We DONT refresh the timer on purpose.
641 * Because almost always the next block will be opened.
643 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
644 struct tpacket_block_desc *pbd1,
645 struct packet_sock *po, unsigned int stat)
647 __u32 status = TP_STATUS_USER | stat;
649 struct tpacket3_hdr *last_pkt;
650 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
652 if (po->stats.tp_drops)
653 status |= TP_STATUS_LOSING;
655 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
656 last_pkt->tp_next_offset = 0;
658 /* Get the ts of the last pkt */
659 if (BLOCK_NUM_PKTS(pbd1)) {
660 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
661 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
663 /* Ok, we tmo'd - so get the current time */
666 h1->ts_last_pkt.ts_sec = ts.tv_sec;
667 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
672 /* Flush the block */
673 prb_flush_block(pkc1, pbd1, status);
675 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
678 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
680 pkc->reset_pending_on_curr_blk = 0;
684 * Side effect of opening a block:
686 * 1) prb_queue is thawed.
687 * 2) retire_blk_timer is refreshed.
690 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
691 struct tpacket_block_desc *pbd1)
694 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
698 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd1))) {
700 /* We could have just memset this but we will lose the
701 * flexibility of making the priv area sticky
703 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
704 BLOCK_NUM_PKTS(pbd1) = 0;
705 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
707 h1->ts_first_pkt.ts_sec = ts.tv_sec;
708 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
709 pkc1->pkblk_start = (char *)pbd1;
710 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
711 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
712 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
713 pbd1->version = pkc1->version;
714 pkc1->prev = pkc1->nxt_offset;
715 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
716 prb_thaw_queue(pkc1);
717 _prb_refresh_rx_retire_blk_timer(pkc1);
724 WARN(1, "ERROR block:%p is NOT FREE status:%d kactive_blk_num:%d\n",
725 pbd1, BLOCK_STATUS(pbd1), pkc1->kactive_blk_num);
731 * Queue freeze logic:
732 * 1) Assume tp_block_nr = 8 blocks.
733 * 2) At time 't0', user opens Rx ring.
734 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
735 * 4) user-space is either sleeping or processing block '0'.
736 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
737 * it will close block-7,loop around and try to fill block '0'.
739 * __packet_lookup_frame_in_block
740 * prb_retire_current_block()
741 * prb_dispatch_next_block()
742 * |->(BLOCK_STATUS == USER) evaluates to true
743 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
744 * 6) Now there are two cases:
745 * 6.1) Link goes idle right after the queue is frozen.
746 * But remember, the last open_block() refreshed the timer.
747 * When this timer expires,it will refresh itself so that we can
748 * re-open block-0 in near future.
749 * 6.2) Link is busy and keeps on receiving packets. This is a simple
750 * case and __packet_lookup_frame_in_block will check if block-0
751 * is free and can now be re-used.
753 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
754 struct packet_sock *po)
756 pkc->reset_pending_on_curr_blk = 1;
757 po->stats_u.stats3.tp_freeze_q_cnt++;
760 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
763 * If the next block is free then we will dispatch it
764 * and return a good offset.
765 * Else, we will freeze the queue.
766 * So, caller must check the return value.
768 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
769 struct packet_sock *po)
771 struct tpacket_block_desc *pbd;
775 /* 1. Get current block num */
776 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
778 /* 2. If this block is currently in_use then freeze the queue */
779 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
780 prb_freeze_queue(pkc, po);
786 * open this block and return the offset where the first packet
787 * needs to get stored.
789 prb_open_block(pkc, pbd);
790 return (void *)pkc->nxt_offset;
793 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
794 struct packet_sock *po, unsigned int status)
796 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
798 /* retire/close the current block */
799 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
801 * Plug the case where copy_bits() is in progress on
802 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
803 * have space to copy the pkt in the current block and
804 * called prb_retire_current_block()
806 * We don't need to worry about the TMO case because
807 * the timer-handler already handled this case.
809 if (!(status & TP_STATUS_BLK_TMO)) {
810 while (atomic_read(&pkc->blk_fill_in_prog)) {
811 /* Waiting for skb_copy_bits to finish... */
815 prb_close_block(pkc, pbd, po, status);
819 WARN(1, "ERROR-pbd[%d]:%p\n", pkc->kactive_blk_num, pbd);
824 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
825 struct tpacket_block_desc *pbd)
827 return TP_STATUS_USER & BLOCK_STATUS(pbd);
830 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
832 return pkc->reset_pending_on_curr_blk;
835 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
837 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
838 atomic_dec(&pkc->blk_fill_in_prog);
841 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
842 struct tpacket3_hdr *ppd)
844 ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
847 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
848 struct tpacket3_hdr *ppd)
850 ppd->hv1.tp_rxhash = 0;
853 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
854 struct tpacket3_hdr *ppd)
856 if (vlan_tx_tag_present(pkc->skb)) {
857 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
858 ppd->tp_status = TP_STATUS_VLAN_VALID;
860 ppd->hv1.tp_vlan_tci = 0;
861 ppd->tp_status = TP_STATUS_AVAILABLE;
865 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
866 struct tpacket3_hdr *ppd)
868 prb_fill_vlan_info(pkc, ppd);
870 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
871 prb_fill_rxhash(pkc, ppd);
873 prb_clear_rxhash(pkc, ppd);
876 static void prb_fill_curr_block(char *curr,
877 struct tpacket_kbdq_core *pkc,
878 struct tpacket_block_desc *pbd,
881 struct tpacket3_hdr *ppd;
883 ppd = (struct tpacket3_hdr *)curr;
884 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
886 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
887 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
888 BLOCK_NUM_PKTS(pbd) += 1;
889 atomic_inc(&pkc->blk_fill_in_prog);
890 prb_run_all_ft_ops(pkc, ppd);
893 /* Assumes caller has the sk->rx_queue.lock */
894 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
900 struct tpacket_kbdq_core *pkc;
901 struct tpacket_block_desc *pbd;
904 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
905 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
907 /* Queue is frozen when user space is lagging behind */
908 if (prb_queue_frozen(pkc)) {
910 * Check if that last block which caused the queue to freeze,
911 * is still in_use by user-space.
913 if (prb_curr_blk_in_use(pkc, pbd)) {
914 /* Can't record this packet */
918 * Ok, the block was released by user-space.
919 * Now let's open that block.
920 * opening a block also thaws the queue.
921 * Thawing is a side effect.
923 prb_open_block(pkc, pbd);
928 curr = pkc->nxt_offset;
930 end = (char *)pbd + pkc->kblk_size;
932 /* first try the current block */
933 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
934 prb_fill_curr_block(curr, pkc, pbd, len);
938 /* Ok, close the current block */
939 prb_retire_current_block(pkc, po, 0);
941 /* Now, try to dispatch the next block */
942 curr = (char *)prb_dispatch_next_block(pkc, po);
944 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
945 prb_fill_curr_block(curr, pkc, pbd, len);
950 * No free blocks are available.user_space hasn't caught up yet.
951 * Queue was just frozen and now this packet will get dropped.
956 static void *packet_current_rx_frame(struct packet_sock *po,
958 int status, unsigned int len)
961 switch (po->tp_version) {
964 curr = packet_lookup_frame(po, &po->rx_ring,
965 po->rx_ring.head, status);
968 return __packet_lookup_frame_in_block(po, skb, status, len);
970 WARN(1, "TPACKET version not supported\n");
976 static void *prb_lookup_block(struct packet_sock *po,
977 struct packet_ring_buffer *rb,
981 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
982 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
984 if (status != BLOCK_STATUS(pbd))
989 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
992 if (rb->prb_bdqc.kactive_blk_num)
993 prev = rb->prb_bdqc.kactive_blk_num-1;
995 prev = rb->prb_bdqc.knum_blocks-1;
999 /* Assumes caller has held the rx_queue.lock */
1000 static void *__prb_previous_block(struct packet_sock *po,
1001 struct packet_ring_buffer *rb,
1004 unsigned int previous = prb_previous_blk_num(rb);
1005 return prb_lookup_block(po, rb, previous, status);
1008 static void *packet_previous_rx_frame(struct packet_sock *po,
1009 struct packet_ring_buffer *rb,
1012 if (po->tp_version <= TPACKET_V2)
1013 return packet_previous_frame(po, rb, status);
1015 return __prb_previous_block(po, rb, status);
1018 static void packet_increment_rx_head(struct packet_sock *po,
1019 struct packet_ring_buffer *rb)
1021 switch (po->tp_version) {
1024 return packet_increment_head(rb);
1027 WARN(1, "TPACKET version not supported.\n");
1033 static void *packet_previous_frame(struct packet_sock *po,
1034 struct packet_ring_buffer *rb,
1037 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1038 return packet_lookup_frame(po, rb, previous, status);
1041 static void packet_increment_head(struct packet_ring_buffer *buff)
1043 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1046 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1048 struct sock *sk = &po->sk;
1051 if (po->prot_hook.func != tpacket_rcv)
1052 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1055 spin_lock(&sk->sk_receive_queue.lock);
1056 if (po->tp_version == TPACKET_V3)
1057 has_room = prb_lookup_block(po, &po->rx_ring,
1058 po->rx_ring.prb_bdqc.kactive_blk_num,
1061 has_room = packet_lookup_frame(po, &po->rx_ring,
1064 spin_unlock(&sk->sk_receive_queue.lock);
1069 static void packet_sock_destruct(struct sock *sk)
1071 skb_queue_purge(&sk->sk_error_queue);
1073 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1074 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1076 if (!sock_flag(sk, SOCK_DEAD)) {
1077 pr_err("Attempt to release alive packet socket: %p\n", sk);
1081 sk_refcnt_debug_dec(sk);
1084 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1086 int x = atomic_read(&f->rr_cur) + 1;
1094 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1095 struct sk_buff *skb,
1098 return (((u64)skb->rxhash) * num) >> 32;
1101 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1102 struct sk_buff *skb,
1107 cur = atomic_read(&f->rr_cur);
1108 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1109 fanout_rr_next(f, num))) != cur)
1114 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1115 struct sk_buff *skb,
1118 return smp_processor_id() % num;
1121 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1122 struct sk_buff *skb,
1123 unsigned int idx, unsigned int skip,
1128 i = j = min_t(int, f->next[idx], num - 1);
1130 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1142 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1144 return f->flags & (flag >> 8);
1147 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1148 struct packet_type *pt, struct net_device *orig_dev)
1150 struct packet_fanout *f = pt->af_packet_priv;
1151 unsigned int num = f->num_members;
1152 struct packet_sock *po;
1155 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1162 case PACKET_FANOUT_HASH:
1164 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1165 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1169 skb_get_rxhash(skb);
1170 idx = fanout_demux_hash(f, skb, num);
1172 case PACKET_FANOUT_LB:
1173 idx = fanout_demux_lb(f, skb, num);
1175 case PACKET_FANOUT_CPU:
1176 idx = fanout_demux_cpu(f, skb, num);
1178 case PACKET_FANOUT_ROLLOVER:
1179 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1183 po = pkt_sk(f->arr[idx]);
1184 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1185 unlikely(!packet_rcv_has_room(po, skb))) {
1186 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1187 po = pkt_sk(f->arr[idx]);
1190 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1193 DEFINE_MUTEX(fanout_mutex);
1194 EXPORT_SYMBOL_GPL(fanout_mutex);
1195 static LIST_HEAD(fanout_list);
1197 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1199 struct packet_fanout *f = po->fanout;
1201 spin_lock(&f->lock);
1202 f->arr[f->num_members] = sk;
1205 spin_unlock(&f->lock);
1208 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1210 struct packet_fanout *f = po->fanout;
1213 spin_lock(&f->lock);
1214 for (i = 0; i < f->num_members; i++) {
1215 if (f->arr[i] == sk)
1218 BUG_ON(i >= f->num_members);
1219 f->arr[i] = f->arr[f->num_members - 1];
1221 spin_unlock(&f->lock);
1224 static bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
1226 if (ptype->af_packet_priv == (void*)((struct packet_sock *)sk)->fanout)
1232 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1234 struct packet_sock *po = pkt_sk(sk);
1235 struct packet_fanout *f, *match;
1236 u8 type = type_flags & 0xff;
1237 u8 flags = type_flags >> 8;
1241 case PACKET_FANOUT_ROLLOVER:
1242 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1244 case PACKET_FANOUT_HASH:
1245 case PACKET_FANOUT_LB:
1246 case PACKET_FANOUT_CPU:
1258 mutex_lock(&fanout_mutex);
1260 list_for_each_entry(f, &fanout_list, list) {
1262 read_pnet(&f->net) == sock_net(sk)) {
1268 if (match && match->flags != flags)
1272 match = kzalloc(sizeof(*match), GFP_KERNEL);
1275 write_pnet(&match->net, sock_net(sk));
1278 match->flags = flags;
1279 atomic_set(&match->rr_cur, 0);
1280 INIT_LIST_HEAD(&match->list);
1281 spin_lock_init(&match->lock);
1282 atomic_set(&match->sk_ref, 0);
1283 match->prot_hook.type = po->prot_hook.type;
1284 match->prot_hook.dev = po->prot_hook.dev;
1285 match->prot_hook.func = packet_rcv_fanout;
1286 match->prot_hook.af_packet_priv = match;
1287 match->prot_hook.id_match = match_fanout_group;
1288 dev_add_pack(&match->prot_hook);
1289 list_add(&match->list, &fanout_list);
1292 if (match->type == type &&
1293 match->prot_hook.type == po->prot_hook.type &&
1294 match->prot_hook.dev == po->prot_hook.dev) {
1296 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1297 __dev_remove_pack(&po->prot_hook);
1299 atomic_inc(&match->sk_ref);
1300 __fanout_link(sk, po);
1305 mutex_unlock(&fanout_mutex);
1309 static void fanout_release(struct sock *sk)
1311 struct packet_sock *po = pkt_sk(sk);
1312 struct packet_fanout *f;
1318 mutex_lock(&fanout_mutex);
1321 if (atomic_dec_and_test(&f->sk_ref)) {
1323 dev_remove_pack(&f->prot_hook);
1326 mutex_unlock(&fanout_mutex);
1329 static const struct proto_ops packet_ops;
1331 static const struct proto_ops packet_ops_spkt;
1333 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1334 struct packet_type *pt, struct net_device *orig_dev)
1337 struct sockaddr_pkt *spkt;
1340 * When we registered the protocol we saved the socket in the data
1341 * field for just this event.
1344 sk = pt->af_packet_priv;
1347 * Yank back the headers [hope the device set this
1348 * right or kerboom...]
1350 * Incoming packets have ll header pulled,
1353 * For outgoing ones skb->data == skb_mac_header(skb)
1354 * so that this procedure is noop.
1357 if (skb->pkt_type == PACKET_LOOPBACK)
1360 if (!net_eq(dev_net(dev), sock_net(sk)))
1363 skb = skb_share_check(skb, GFP_ATOMIC);
1367 /* drop any routing info */
1370 /* drop conntrack reference */
1373 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1375 skb_push(skb, skb->data - skb_mac_header(skb));
1378 * The SOCK_PACKET socket receives _all_ frames.
1381 spkt->spkt_family = dev->type;
1382 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1383 spkt->spkt_protocol = skb->protocol;
1386 * Charge the memory to the socket. This is done specifically
1387 * to prevent sockets using all the memory up.
1390 if (sock_queue_rcv_skb(sk, skb) == 0)
1401 * Output a raw packet to a device layer. This bypasses all the other
1402 * protocol layers and you must therefore supply it with a complete frame
1405 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1406 struct msghdr *msg, size_t len)
1408 struct sock *sk = sock->sk;
1409 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1410 struct sk_buff *skb = NULL;
1411 struct net_device *dev;
1417 * Get and verify the address.
1421 if (msg->msg_namelen < sizeof(struct sockaddr))
1423 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1424 proto = saddr->spkt_protocol;
1426 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1429 * Find the device first to size check it
1432 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1435 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1441 if (!(dev->flags & IFF_UP))
1445 * You may not queue a frame bigger than the mtu. This is the lowest level
1446 * raw protocol and you must do your own fragmentation at this level.
1449 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1450 if (!netif_supports_nofcs(dev)) {
1451 err = -EPROTONOSUPPORT;
1454 extra_len = 4; /* We're doing our own CRC */
1458 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1462 size_t reserved = LL_RESERVED_SPACE(dev);
1463 int tlen = dev->needed_tailroom;
1464 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1467 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1470 /* FIXME: Save some space for broken drivers that write a hard
1471 * header at transmission time by themselves. PPP is the notable
1472 * one here. This should really be fixed at the driver level.
1474 skb_reserve(skb, reserved);
1475 skb_reset_network_header(skb);
1477 /* Try to align data part correctly */
1482 skb_reset_network_header(skb);
1484 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1490 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1491 /* Earlier code assumed this would be a VLAN pkt,
1492 * double-check this now that we have the actual
1495 struct ethhdr *ehdr;
1496 skb_reset_mac_header(skb);
1497 ehdr = eth_hdr(skb);
1498 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1504 skb->protocol = proto;
1506 skb->priority = sk->sk_priority;
1507 skb->mark = sk->sk_mark;
1508 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1512 if (unlikely(extra_len == 4))
1515 dev_queue_xmit(skb);
1526 static unsigned int run_filter(const struct sk_buff *skb,
1527 const struct sock *sk,
1530 struct sk_filter *filter;
1533 filter = rcu_dereference(sk->sk_filter);
1535 res = SK_RUN_FILTER(filter, skb);
1542 * This function makes lazy skb cloning in hope that most of packets
1543 * are discarded by BPF.
1545 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1546 * and skb->cb are mangled. It works because (and until) packets
1547 * falling here are owned by current CPU. Output packets are cloned
1548 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1549 * sequencially, so that if we return skb to original state on exit,
1550 * we will not harm anyone.
1553 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1554 struct packet_type *pt, struct net_device *orig_dev)
1557 struct sockaddr_ll *sll;
1558 struct packet_sock *po;
1559 u8 *skb_head = skb->data;
1560 int skb_len = skb->len;
1561 unsigned int snaplen, res;
1563 if (skb->pkt_type == PACKET_LOOPBACK)
1566 sk = pt->af_packet_priv;
1569 if (!net_eq(dev_net(dev), sock_net(sk)))
1574 if (dev->header_ops) {
1575 /* The device has an explicit notion of ll header,
1576 * exported to higher levels.
1578 * Otherwise, the device hides details of its frame
1579 * structure, so that corresponding packet head is
1580 * never delivered to user.
1582 if (sk->sk_type != SOCK_DGRAM)
1583 skb_push(skb, skb->data - skb_mac_header(skb));
1584 else if (skb->pkt_type == PACKET_OUTGOING) {
1585 /* Special case: outgoing packets have ll header at head */
1586 skb_pull(skb, skb_network_offset(skb));
1592 res = run_filter(skb, sk, snaplen);
1594 goto drop_n_restore;
1598 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1601 if (skb_shared(skb)) {
1602 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1606 if (skb_head != skb->data) {
1607 skb->data = skb_head;
1614 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1617 sll = &PACKET_SKB_CB(skb)->sa.ll;
1618 sll->sll_family = AF_PACKET;
1619 sll->sll_hatype = dev->type;
1620 sll->sll_protocol = skb->protocol;
1621 sll->sll_pkttype = skb->pkt_type;
1622 if (unlikely(po->origdev))
1623 sll->sll_ifindex = orig_dev->ifindex;
1625 sll->sll_ifindex = dev->ifindex;
1627 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1629 PACKET_SKB_CB(skb)->origlen = skb->len;
1631 if (pskb_trim(skb, snaplen))
1634 skb_set_owner_r(skb, sk);
1638 /* drop conntrack reference */
1641 spin_lock(&sk->sk_receive_queue.lock);
1642 po->stats.tp_packets++;
1643 skb->dropcount = atomic_read(&sk->sk_drops);
1644 __skb_queue_tail(&sk->sk_receive_queue, skb);
1645 spin_unlock(&sk->sk_receive_queue.lock);
1646 sk->sk_data_ready(sk, skb->len);
1650 spin_lock(&sk->sk_receive_queue.lock);
1651 po->stats.tp_drops++;
1652 atomic_inc(&sk->sk_drops);
1653 spin_unlock(&sk->sk_receive_queue.lock);
1656 if (skb_head != skb->data && skb_shared(skb)) {
1657 skb->data = skb_head;
1665 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1666 struct packet_type *pt, struct net_device *orig_dev)
1669 struct packet_sock *po;
1670 struct sockaddr_ll *sll;
1672 struct tpacket_hdr *h1;
1673 struct tpacket2_hdr *h2;
1674 struct tpacket3_hdr *h3;
1677 u8 *skb_head = skb->data;
1678 int skb_len = skb->len;
1679 unsigned int snaplen, res;
1680 unsigned long status = TP_STATUS_USER;
1681 unsigned short macoff, netoff, hdrlen;
1682 struct sk_buff *copy_skb = NULL;
1685 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
1687 if (skb->pkt_type == PACKET_LOOPBACK)
1690 sk = pt->af_packet_priv;
1693 if (!net_eq(dev_net(dev), sock_net(sk)))
1696 if (dev->header_ops) {
1697 if (sk->sk_type != SOCK_DGRAM)
1698 skb_push(skb, skb->data - skb_mac_header(skb));
1699 else if (skb->pkt_type == PACKET_OUTGOING) {
1700 /* Special case: outgoing packets have ll header at head */
1701 skb_pull(skb, skb_network_offset(skb));
1705 if (skb->ip_summed == CHECKSUM_PARTIAL)
1706 status |= TP_STATUS_CSUMNOTREADY;
1710 res = run_filter(skb, sk, snaplen);
1712 goto drop_n_restore;
1716 if (sk->sk_type == SOCK_DGRAM) {
1717 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1720 unsigned int maclen = skb_network_offset(skb);
1721 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1722 (maclen < 16 ? 16 : maclen)) +
1724 macoff = netoff - maclen;
1726 if (po->tp_version <= TPACKET_V2) {
1727 if (macoff + snaplen > po->rx_ring.frame_size) {
1728 if (po->copy_thresh &&
1729 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1730 if (skb_shared(skb)) {
1731 copy_skb = skb_clone(skb, GFP_ATOMIC);
1733 copy_skb = skb_get(skb);
1734 skb_head = skb->data;
1737 skb_set_owner_r(copy_skb, sk);
1739 snaplen = po->rx_ring.frame_size - macoff;
1740 if ((int)snaplen < 0)
1744 spin_lock(&sk->sk_receive_queue.lock);
1745 h.raw = packet_current_rx_frame(po, skb,
1746 TP_STATUS_KERNEL, (macoff+snaplen));
1749 if (po->tp_version <= TPACKET_V2) {
1750 packet_increment_rx_head(po, &po->rx_ring);
1752 * LOSING will be reported till you read the stats,
1753 * because it's COR - Clear On Read.
1754 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1757 if (po->stats.tp_drops)
1758 status |= TP_STATUS_LOSING;
1760 po->stats.tp_packets++;
1762 status |= TP_STATUS_COPY;
1763 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1765 spin_unlock(&sk->sk_receive_queue.lock);
1767 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1769 switch (po->tp_version) {
1771 h.h1->tp_len = skb->len;
1772 h.h1->tp_snaplen = snaplen;
1773 h.h1->tp_mac = macoff;
1774 h.h1->tp_net = netoff;
1775 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1776 && shhwtstamps->syststamp.tv64)
1777 tv = ktime_to_timeval(shhwtstamps->syststamp);
1778 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1779 && shhwtstamps->hwtstamp.tv64)
1780 tv = ktime_to_timeval(shhwtstamps->hwtstamp);
1781 else if (skb->tstamp.tv64)
1782 tv = ktime_to_timeval(skb->tstamp);
1784 do_gettimeofday(&tv);
1785 h.h1->tp_sec = tv.tv_sec;
1786 h.h1->tp_usec = tv.tv_usec;
1787 hdrlen = sizeof(*h.h1);
1790 h.h2->tp_len = skb->len;
1791 h.h2->tp_snaplen = snaplen;
1792 h.h2->tp_mac = macoff;
1793 h.h2->tp_net = netoff;
1794 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1795 && shhwtstamps->syststamp.tv64)
1796 ts = ktime_to_timespec(shhwtstamps->syststamp);
1797 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1798 && shhwtstamps->hwtstamp.tv64)
1799 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1800 else if (skb->tstamp.tv64)
1801 ts = ktime_to_timespec(skb->tstamp);
1803 getnstimeofday(&ts);
1804 h.h2->tp_sec = ts.tv_sec;
1805 h.h2->tp_nsec = ts.tv_nsec;
1806 if (vlan_tx_tag_present(skb)) {
1807 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1808 status |= TP_STATUS_VLAN_VALID;
1810 h.h2->tp_vlan_tci = 0;
1812 h.h2->tp_padding = 0;
1813 hdrlen = sizeof(*h.h2);
1816 /* tp_nxt_offset,vlan are already populated above.
1817 * So DONT clear those fields here
1819 h.h3->tp_status |= status;
1820 h.h3->tp_len = skb->len;
1821 h.h3->tp_snaplen = snaplen;
1822 h.h3->tp_mac = macoff;
1823 h.h3->tp_net = netoff;
1824 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
1825 && shhwtstamps->syststamp.tv64)
1826 ts = ktime_to_timespec(shhwtstamps->syststamp);
1827 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
1828 && shhwtstamps->hwtstamp.tv64)
1829 ts = ktime_to_timespec(shhwtstamps->hwtstamp);
1830 else if (skb->tstamp.tv64)
1831 ts = ktime_to_timespec(skb->tstamp);
1833 getnstimeofday(&ts);
1834 h.h3->tp_sec = ts.tv_sec;
1835 h.h3->tp_nsec = ts.tv_nsec;
1836 hdrlen = sizeof(*h.h3);
1842 sll = h.raw + TPACKET_ALIGN(hdrlen);
1843 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1844 sll->sll_family = AF_PACKET;
1845 sll->sll_hatype = dev->type;
1846 sll->sll_protocol = skb->protocol;
1847 sll->sll_pkttype = skb->pkt_type;
1848 if (unlikely(po->origdev))
1849 sll->sll_ifindex = orig_dev->ifindex;
1851 sll->sll_ifindex = dev->ifindex;
1854 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
1858 if (po->tp_version <= TPACKET_V2) {
1859 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw
1860 + macoff + snaplen);
1861 for (start = h.raw; start < end; start += PAGE_SIZE)
1862 flush_dcache_page(pgv_to_page(start));
1867 if (po->tp_version <= TPACKET_V2)
1868 __packet_set_status(po, h.raw, status);
1870 prb_clear_blk_fill_status(&po->rx_ring);
1872 sk->sk_data_ready(sk, 0);
1875 if (skb_head != skb->data && skb_shared(skb)) {
1876 skb->data = skb_head;
1884 po->stats.tp_drops++;
1885 spin_unlock(&sk->sk_receive_queue.lock);
1887 sk->sk_data_ready(sk, 0);
1888 kfree_skb(copy_skb);
1889 goto drop_n_restore;
1892 static void tpacket_destruct_skb(struct sk_buff *skb)
1894 struct packet_sock *po = pkt_sk(skb->sk);
1897 if (likely(po->tx_ring.pg_vec)) {
1898 ph = skb_shinfo(skb)->destructor_arg;
1899 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
1900 atomic_dec(&po->tx_ring.pending);
1901 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
1907 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
1908 void *frame, struct net_device *dev, int size_max,
1909 __be16 proto, unsigned char *addr, int hlen)
1912 struct tpacket_hdr *h1;
1913 struct tpacket2_hdr *h2;
1916 int to_write, offset, len, tp_len, nr_frags, len_max;
1917 struct socket *sock = po->sk.sk_socket;
1924 skb->protocol = proto;
1926 skb->priority = po->sk.sk_priority;
1927 skb->mark = po->sk.sk_mark;
1928 skb_shinfo(skb)->destructor_arg = ph.raw;
1930 switch (po->tp_version) {
1932 tp_len = ph.h2->tp_len;
1935 tp_len = ph.h1->tp_len;
1938 if (unlikely(tp_len > size_max)) {
1939 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
1943 skb_reserve(skb, hlen);
1944 skb_reset_network_header(skb);
1946 if (po->tp_tx_has_off) {
1947 int off_min, off_max, off;
1948 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
1949 off_max = po->tx_ring.frame_size - tp_len;
1950 if (sock->type == SOCK_DGRAM) {
1951 switch (po->tp_version) {
1953 off = ph.h2->tp_net;
1956 off = ph.h1->tp_net;
1960 switch (po->tp_version) {
1962 off = ph.h2->tp_mac;
1965 off = ph.h1->tp_mac;
1969 if (unlikely((off < off_min) || (off_max < off)))
1971 data = ph.raw + off;
1973 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
1977 if (sock->type == SOCK_DGRAM) {
1978 err = dev_hard_header(skb, dev, ntohs(proto), addr,
1980 if (unlikely(err < 0))
1982 } else if (dev->hard_header_len) {
1983 /* net device doesn't like empty head */
1984 if (unlikely(tp_len <= dev->hard_header_len)) {
1985 pr_err("packet size is too short (%d < %d)\n",
1986 tp_len, dev->hard_header_len);
1990 skb_push(skb, dev->hard_header_len);
1991 err = skb_store_bits(skb, 0, data,
1992 dev->hard_header_len);
1996 data += dev->hard_header_len;
1997 to_write -= dev->hard_header_len;
2000 offset = offset_in_page(data);
2001 len_max = PAGE_SIZE - offset;
2002 len = ((to_write > len_max) ? len_max : to_write);
2004 skb->data_len = to_write;
2005 skb->len += to_write;
2006 skb->truesize += to_write;
2007 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2009 while (likely(to_write)) {
2010 nr_frags = skb_shinfo(skb)->nr_frags;
2012 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2013 pr_err("Packet exceed the number of skb frags(%lu)\n",
2018 page = pgv_to_page(data);
2020 flush_dcache_page(page);
2022 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2025 len_max = PAGE_SIZE;
2026 len = ((to_write > len_max) ? len_max : to_write);
2032 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2034 struct sk_buff *skb;
2035 struct net_device *dev;
2037 bool need_rls_dev = false;
2038 int err, reserve = 0;
2040 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2041 int tp_len, size_max;
2042 unsigned char *addr;
2044 int status = TP_STATUS_AVAILABLE;
2047 mutex_lock(&po->pg_vec_lock);
2049 if (saddr == NULL) {
2050 dev = po->prot_hook.dev;
2055 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2057 if (msg->msg_namelen < (saddr->sll_halen
2058 + offsetof(struct sockaddr_ll,
2061 proto = saddr->sll_protocol;
2062 addr = saddr->sll_addr;
2063 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2064 need_rls_dev = true;
2068 if (unlikely(dev == NULL))
2071 reserve = dev->hard_header_len;
2074 if (unlikely(!(dev->flags & IFF_UP)))
2077 size_max = po->tx_ring.frame_size
2078 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2080 if (size_max > dev->mtu + reserve)
2081 size_max = dev->mtu + reserve;
2084 ph = packet_current_frame(po, &po->tx_ring,
2085 TP_STATUS_SEND_REQUEST);
2087 if (unlikely(ph == NULL)) {
2092 status = TP_STATUS_SEND_REQUEST;
2093 hlen = LL_RESERVED_SPACE(dev);
2094 tlen = dev->needed_tailroom;
2095 skb = sock_alloc_send_skb(&po->sk,
2096 hlen + tlen + sizeof(struct sockaddr_ll),
2099 if (unlikely(skb == NULL))
2102 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2105 if (unlikely(tp_len < 0)) {
2107 __packet_set_status(po, ph,
2108 TP_STATUS_AVAILABLE);
2109 packet_increment_head(&po->tx_ring);
2113 status = TP_STATUS_WRONG_FORMAT;
2119 skb->destructor = tpacket_destruct_skb;
2120 __packet_set_status(po, ph, TP_STATUS_SENDING);
2121 atomic_inc(&po->tx_ring.pending);
2123 status = TP_STATUS_SEND_REQUEST;
2124 err = dev_queue_xmit(skb);
2125 if (unlikely(err > 0)) {
2126 err = net_xmit_errno(err);
2127 if (err && __packet_get_status(po, ph) ==
2128 TP_STATUS_AVAILABLE) {
2129 /* skb was destructed already */
2134 * skb was dropped but not destructed yet;
2135 * let's treat it like congestion or err < 0
2139 packet_increment_head(&po->tx_ring);
2141 } while (likely((ph != NULL) ||
2142 ((!(msg->msg_flags & MSG_DONTWAIT)) &&
2143 (atomic_read(&po->tx_ring.pending))))
2150 __packet_set_status(po, ph, status);
2156 mutex_unlock(&po->pg_vec_lock);
2160 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2161 size_t reserve, size_t len,
2162 size_t linear, int noblock,
2165 struct sk_buff *skb;
2167 /* Under a page? Don't bother with paged skb. */
2168 if (prepad + len < PAGE_SIZE || !linear)
2171 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2176 skb_reserve(skb, reserve);
2177 skb_put(skb, linear);
2178 skb->data_len = len - linear;
2179 skb->len += len - linear;
2184 static int packet_snd(struct socket *sock,
2185 struct msghdr *msg, size_t len)
2187 struct sock *sk = sock->sk;
2188 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
2189 struct sk_buff *skb;
2190 struct net_device *dev;
2192 bool need_rls_dev = false;
2193 unsigned char *addr;
2194 int err, reserve = 0;
2195 struct virtio_net_hdr vnet_hdr = { 0 };
2198 struct packet_sock *po = pkt_sk(sk);
2199 unsigned short gso_type = 0;
2204 * Get and verify the address.
2207 if (saddr == NULL) {
2208 dev = po->prot_hook.dev;
2213 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2215 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2217 proto = saddr->sll_protocol;
2218 addr = saddr->sll_addr;
2219 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2220 need_rls_dev = true;
2226 if (sock->type == SOCK_RAW)
2227 reserve = dev->hard_header_len;
2230 if (!(dev->flags & IFF_UP))
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)
2281 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2282 if (!netif_supports_nofcs(dev)) {
2283 err = -EPROTONOSUPPORT;
2286 extra_len = 4; /* We're doing our own CRC */
2290 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2294 hlen = LL_RESERVED_SPACE(dev);
2295 tlen = dev->needed_tailroom;
2296 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2297 msg->msg_flags & MSG_DONTWAIT, &err);
2301 skb_set_network_header(skb, reserve);
2304 if (sock->type == SOCK_DGRAM &&
2305 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2308 /* Returns -EFAULT on error */
2309 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2312 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2316 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2317 /* Earlier code assumed this would be a VLAN pkt,
2318 * double-check this now that we have the actual
2321 struct ethhdr *ehdr;
2322 skb_reset_mac_header(skb);
2323 ehdr = eth_hdr(skb);
2324 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2330 skb->protocol = proto;
2332 skb->priority = sk->sk_priority;
2333 skb->mark = sk->sk_mark;
2335 if (po->has_vnet_hdr) {
2336 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2337 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2338 vnet_hdr.csum_offset)) {
2344 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2345 skb_shinfo(skb)->gso_type = gso_type;
2347 /* Header must be checked, and gso_segs computed. */
2348 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2349 skb_shinfo(skb)->gso_segs = 0;
2351 len += vnet_hdr_len;
2354 if (unlikely(extra_len == 4))
2361 err = dev_queue_xmit(skb);
2362 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2373 if (dev && need_rls_dev)
2379 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2380 struct msghdr *msg, size_t len)
2382 struct sock *sk = sock->sk;
2383 struct packet_sock *po = pkt_sk(sk);
2384 if (po->tx_ring.pg_vec)
2385 return tpacket_snd(po, msg);
2387 return packet_snd(sock, msg, len);
2391 * Close a PACKET socket. This is fairly simple. We immediately go
2392 * to 'closed' state and remove our protocol entry in the device list.
2395 static int packet_release(struct socket *sock)
2397 struct sock *sk = sock->sk;
2398 struct packet_sock *po;
2400 union tpacket_req_u req_u;
2408 mutex_lock(&net->packet.sklist_lock);
2409 sk_del_node_init_rcu(sk);
2410 mutex_unlock(&net->packet.sklist_lock);
2413 sock_prot_inuse_add(net, sk->sk_prot, -1);
2416 spin_lock(&po->bind_lock);
2417 unregister_prot_hook(sk, false);
2418 if (po->prot_hook.dev) {
2419 dev_put(po->prot_hook.dev);
2420 po->prot_hook.dev = NULL;
2422 spin_unlock(&po->bind_lock);
2424 packet_flush_mclist(sk);
2426 if (po->rx_ring.pg_vec) {
2427 memset(&req_u, 0, sizeof(req_u));
2428 packet_set_ring(sk, &req_u, 1, 0);
2431 if (po->tx_ring.pg_vec) {
2432 memset(&req_u, 0, sizeof(req_u));
2433 packet_set_ring(sk, &req_u, 1, 1);
2440 * Now the socket is dead. No more input will appear.
2447 skb_queue_purge(&sk->sk_receive_queue);
2448 sk_refcnt_debug_release(sk);
2455 * Attach a packet hook.
2458 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
2460 struct packet_sock *po = pkt_sk(sk);
2471 spin_lock(&po->bind_lock);
2472 unregister_prot_hook(sk, true);
2474 po->prot_hook.type = protocol;
2475 if (po->prot_hook.dev)
2476 dev_put(po->prot_hook.dev);
2477 po->prot_hook.dev = dev;
2479 po->ifindex = dev ? dev->ifindex : 0;
2484 if (!dev || (dev->flags & IFF_UP)) {
2485 register_prot_hook(sk);
2487 sk->sk_err = ENETDOWN;
2488 if (!sock_flag(sk, SOCK_DEAD))
2489 sk->sk_error_report(sk);
2493 spin_unlock(&po->bind_lock);
2499 * Bind a packet socket to a device
2502 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2505 struct sock *sk = sock->sk;
2507 struct net_device *dev;
2514 if (addr_len != sizeof(struct sockaddr))
2516 strlcpy(name, uaddr->sa_data, sizeof(name));
2518 dev = dev_get_by_name(sock_net(sk), name);
2520 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2524 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2526 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2527 struct sock *sk = sock->sk;
2528 struct net_device *dev = NULL;
2536 if (addr_len < sizeof(struct sockaddr_ll))
2538 if (sll->sll_family != AF_PACKET)
2541 if (sll->sll_ifindex) {
2543 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2547 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2553 static struct proto packet_proto = {
2555 .owner = THIS_MODULE,
2556 .obj_size = sizeof(struct packet_sock),
2560 * Create a packet of type SOCK_PACKET.
2563 static int packet_create(struct net *net, struct socket *sock, int protocol,
2567 struct packet_sock *po;
2568 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2571 if (!ns_capable(net->user_ns, CAP_NET_RAW))
2573 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2574 sock->type != SOCK_PACKET)
2575 return -ESOCKTNOSUPPORT;
2577 sock->state = SS_UNCONNECTED;
2580 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2584 sock->ops = &packet_ops;
2585 if (sock->type == SOCK_PACKET)
2586 sock->ops = &packet_ops_spkt;
2588 sock_init_data(sock, sk);
2591 sk->sk_family = PF_PACKET;
2594 sk->sk_destruct = packet_sock_destruct;
2595 sk_refcnt_debug_inc(sk);
2598 * Attach a protocol block
2601 spin_lock_init(&po->bind_lock);
2602 mutex_init(&po->pg_vec_lock);
2603 po->prot_hook.func = packet_rcv;
2605 if (sock->type == SOCK_PACKET)
2606 po->prot_hook.func = packet_rcv_spkt;
2608 po->prot_hook.af_packet_priv = sk;
2611 po->prot_hook.type = proto;
2612 register_prot_hook(sk);
2615 mutex_lock(&net->packet.sklist_lock);
2616 sk_add_node_rcu(sk, &net->packet.sklist);
2617 mutex_unlock(&net->packet.sklist_lock);
2620 sock_prot_inuse_add(net, &packet_proto, 1);
2628 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
2630 struct sock_exterr_skb *serr;
2631 struct sk_buff *skb, *skb2;
2635 skb = skb_dequeue(&sk->sk_error_queue);
2641 msg->msg_flags |= MSG_TRUNC;
2644 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2648 sock_recv_timestamp(msg, sk, skb);
2650 serr = SKB_EXT_ERR(skb);
2651 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
2652 sizeof(serr->ee), &serr->ee);
2654 msg->msg_flags |= MSG_ERRQUEUE;
2657 /* Reset and regenerate socket error */
2658 spin_lock_bh(&sk->sk_error_queue.lock);
2660 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2661 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2662 spin_unlock_bh(&sk->sk_error_queue.lock);
2663 sk->sk_error_report(sk);
2665 spin_unlock_bh(&sk->sk_error_queue.lock);
2674 * Pull a packet from our receive queue and hand it to the user.
2675 * If necessary we block.
2678 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2679 struct msghdr *msg, size_t len, int flags)
2681 struct sock *sk = sock->sk;
2682 struct sk_buff *skb;
2684 struct sockaddr_ll *sll;
2685 int vnet_hdr_len = 0;
2688 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2692 /* What error should we return now? EUNATTACH? */
2693 if (pkt_sk(sk)->ifindex < 0)
2697 if (flags & MSG_ERRQUEUE) {
2698 err = packet_recv_error(sk, msg, len);
2703 * Call the generic datagram receiver. This handles all sorts
2704 * of horrible races and re-entrancy so we can forget about it
2705 * in the protocol layers.
2707 * Now it will return ENETDOWN, if device have just gone down,
2708 * but then it will block.
2711 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2714 * An error occurred so return it. Because skb_recv_datagram()
2715 * handles the blocking we don't see and worry about blocking
2722 if (pkt_sk(sk)->has_vnet_hdr) {
2723 struct virtio_net_hdr vnet_hdr = { 0 };
2726 vnet_hdr_len = sizeof(vnet_hdr);
2727 if (len < vnet_hdr_len)
2730 len -= vnet_hdr_len;
2732 if (skb_is_gso(skb)) {
2733 struct skb_shared_info *sinfo = skb_shinfo(skb);
2735 /* This is a hint as to how much should be linear. */
2736 vnet_hdr.hdr_len = skb_headlen(skb);
2737 vnet_hdr.gso_size = sinfo->gso_size;
2738 if (sinfo->gso_type & SKB_GSO_TCPV4)
2739 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2740 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2741 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2742 else if (sinfo->gso_type & SKB_GSO_UDP)
2743 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2744 else if (sinfo->gso_type & SKB_GSO_FCOE)
2748 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2749 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2751 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2753 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2754 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2755 vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2756 vnet_hdr.csum_offset = skb->csum_offset;
2757 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2758 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2759 } /* else everything is zero */
2761 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2768 * If the address length field is there to be filled in, we fill
2772 sll = &PACKET_SKB_CB(skb)->sa.ll;
2773 if (sock->type == SOCK_PACKET)
2774 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2776 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
2779 * You lose any data beyond the buffer you gave. If it worries a
2780 * user program they can ask the device for its MTU anyway.
2786 msg->msg_flags |= MSG_TRUNC;
2789 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2793 sock_recv_ts_and_drops(msg, sk, skb);
2796 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2799 if (pkt_sk(sk)->auxdata) {
2800 struct tpacket_auxdata aux;
2802 aux.tp_status = TP_STATUS_USER;
2803 if (skb->ip_summed == CHECKSUM_PARTIAL)
2804 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2805 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2806 aux.tp_snaplen = skb->len;
2808 aux.tp_net = skb_network_offset(skb);
2809 if (vlan_tx_tag_present(skb)) {
2810 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2811 aux.tp_status |= TP_STATUS_VLAN_VALID;
2813 aux.tp_vlan_tci = 0;
2816 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2820 * Free or return the buffer as appropriate. Again this
2821 * hides all the races and re-entrancy issues from us.
2823 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2826 skb_free_datagram(sk, skb);
2831 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2832 int *uaddr_len, int peer)
2834 struct net_device *dev;
2835 struct sock *sk = sock->sk;
2840 uaddr->sa_family = AF_PACKET;
2842 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
2844 strncpy(uaddr->sa_data, dev->name, 14);
2846 memset(uaddr->sa_data, 0, 14);
2848 *uaddr_len = sizeof(*uaddr);
2853 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
2854 int *uaddr_len, int peer)
2856 struct net_device *dev;
2857 struct sock *sk = sock->sk;
2858 struct packet_sock *po = pkt_sk(sk);
2859 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
2864 sll->sll_family = AF_PACKET;
2865 sll->sll_ifindex = po->ifindex;
2866 sll->sll_protocol = po->num;
2867 sll->sll_pkttype = 0;
2869 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
2871 sll->sll_hatype = dev->type;
2872 sll->sll_halen = dev->addr_len;
2873 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
2875 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
2879 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
2884 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
2888 case PACKET_MR_MULTICAST:
2889 if (i->alen != dev->addr_len)
2892 return dev_mc_add(dev, i->addr);
2894 return dev_mc_del(dev, i->addr);
2896 case PACKET_MR_PROMISC:
2897 return dev_set_promiscuity(dev, what);
2899 case PACKET_MR_ALLMULTI:
2900 return dev_set_allmulti(dev, what);
2902 case PACKET_MR_UNICAST:
2903 if (i->alen != dev->addr_len)
2906 return dev_uc_add(dev, i->addr);
2908 return dev_uc_del(dev, i->addr);
2916 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
2918 for ( ; i; i = i->next) {
2919 if (i->ifindex == dev->ifindex)
2920 packet_dev_mc(dev, i, what);
2924 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
2926 struct packet_sock *po = pkt_sk(sk);
2927 struct packet_mclist *ml, *i;
2928 struct net_device *dev;
2934 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
2939 if (mreq->mr_alen > dev->addr_len)
2943 i = kmalloc(sizeof(*i), GFP_KERNEL);
2948 for (ml = po->mclist; ml; ml = ml->next) {
2949 if (ml->ifindex == mreq->mr_ifindex &&
2950 ml->type == mreq->mr_type &&
2951 ml->alen == mreq->mr_alen &&
2952 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2954 /* Free the new element ... */
2960 i->type = mreq->mr_type;
2961 i->ifindex = mreq->mr_ifindex;
2962 i->alen = mreq->mr_alen;
2963 memcpy(i->addr, mreq->mr_address, i->alen);
2965 i->next = po->mclist;
2967 err = packet_dev_mc(dev, i, 1);
2969 po->mclist = i->next;
2978 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
2980 struct packet_mclist *ml, **mlp;
2984 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
2985 if (ml->ifindex == mreq->mr_ifindex &&
2986 ml->type == mreq->mr_type &&
2987 ml->alen == mreq->mr_alen &&
2988 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
2989 if (--ml->count == 0) {
2990 struct net_device *dev;
2992 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
2994 packet_dev_mc(dev, ml, -1);
3002 return -EADDRNOTAVAIL;
3005 static void packet_flush_mclist(struct sock *sk)
3007 struct packet_sock *po = pkt_sk(sk);
3008 struct packet_mclist *ml;
3014 while ((ml = po->mclist) != NULL) {
3015 struct net_device *dev;
3017 po->mclist = ml->next;
3018 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3020 packet_dev_mc(dev, ml, -1);
3027 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3029 struct sock *sk = sock->sk;
3030 struct packet_sock *po = pkt_sk(sk);
3033 if (level != SOL_PACKET)
3034 return -ENOPROTOOPT;
3037 case PACKET_ADD_MEMBERSHIP:
3038 case PACKET_DROP_MEMBERSHIP:
3040 struct packet_mreq_max mreq;
3042 memset(&mreq, 0, sizeof(mreq));
3043 if (len < sizeof(struct packet_mreq))
3045 if (len > sizeof(mreq))
3047 if (copy_from_user(&mreq, optval, len))
3049 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3051 if (optname == PACKET_ADD_MEMBERSHIP)
3052 ret = packet_mc_add(sk, &mreq);
3054 ret = packet_mc_drop(sk, &mreq);
3058 case PACKET_RX_RING:
3059 case PACKET_TX_RING:
3061 union tpacket_req_u req_u;
3064 switch (po->tp_version) {
3067 len = sizeof(req_u.req);
3071 len = sizeof(req_u.req3);
3076 if (pkt_sk(sk)->has_vnet_hdr)
3078 if (copy_from_user(&req_u.req, optval, len))
3080 return packet_set_ring(sk, &req_u, 0,
3081 optname == PACKET_TX_RING);
3083 case PACKET_COPY_THRESH:
3087 if (optlen != sizeof(val))
3089 if (copy_from_user(&val, optval, sizeof(val)))
3092 pkt_sk(sk)->copy_thresh = val;
3095 case PACKET_VERSION:
3099 if (optlen != sizeof(val))
3101 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3103 if (copy_from_user(&val, optval, sizeof(val)))
3109 po->tp_version = val;
3115 case PACKET_RESERVE:
3119 if (optlen != sizeof(val))
3121 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3123 if (copy_from_user(&val, optval, sizeof(val)))
3125 po->tp_reserve = val;
3132 if (optlen != sizeof(val))
3134 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3136 if (copy_from_user(&val, optval, sizeof(val)))
3138 po->tp_loss = !!val;
3141 case PACKET_AUXDATA:
3145 if (optlen < sizeof(val))
3147 if (copy_from_user(&val, optval, sizeof(val)))
3150 po->auxdata = !!val;
3153 case PACKET_ORIGDEV:
3157 if (optlen < sizeof(val))
3159 if (copy_from_user(&val, optval, sizeof(val)))
3162 po->origdev = !!val;
3165 case PACKET_VNET_HDR:
3169 if (sock->type != SOCK_RAW)
3171 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3173 if (optlen < sizeof(val))
3175 if (copy_from_user(&val, optval, sizeof(val)))
3178 po->has_vnet_hdr = !!val;
3181 case PACKET_TIMESTAMP:
3185 if (optlen != sizeof(val))
3187 if (copy_from_user(&val, optval, sizeof(val)))
3190 po->tp_tstamp = val;
3197 if (optlen != sizeof(val))
3199 if (copy_from_user(&val, optval, sizeof(val)))
3202 return fanout_add(sk, val & 0xffff, val >> 16);
3204 case PACKET_TX_HAS_OFF:
3208 if (optlen != sizeof(val))
3210 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3212 if (copy_from_user(&val, optval, sizeof(val)))
3214 po->tp_tx_has_off = !!val;
3218 return -ENOPROTOOPT;
3222 static int packet_getsockopt(struct socket *sock, int level, int optname,
3223 char __user *optval, int __user *optlen)
3226 int val, lv = sizeof(val);
3227 struct sock *sk = sock->sk;
3228 struct packet_sock *po = pkt_sk(sk);
3230 struct tpacket_stats st;
3231 union tpacket_stats_u st_u;
3233 if (level != SOL_PACKET)
3234 return -ENOPROTOOPT;
3236 if (get_user(len, optlen))
3243 case PACKET_STATISTICS:
3244 spin_lock_bh(&sk->sk_receive_queue.lock);
3245 if (po->tp_version == TPACKET_V3) {
3246 lv = sizeof(struct tpacket_stats_v3);
3247 memcpy(&st_u.stats3, &po->stats,
3248 sizeof(struct tpacket_stats));
3249 st_u.stats3.tp_freeze_q_cnt =
3250 po->stats_u.stats3.tp_freeze_q_cnt;
3251 st_u.stats3.tp_packets += po->stats.tp_drops;
3252 data = &st_u.stats3;
3254 lv = sizeof(struct tpacket_stats);
3256 st.tp_packets += st.tp_drops;
3259 memset(&po->stats, 0, sizeof(st));
3260 spin_unlock_bh(&sk->sk_receive_queue.lock);
3262 case PACKET_AUXDATA:
3265 case PACKET_ORIGDEV:
3268 case PACKET_VNET_HDR:
3269 val = po->has_vnet_hdr;
3271 case PACKET_VERSION:
3272 val = po->tp_version;
3275 if (len > sizeof(int))
3277 if (copy_from_user(&val, optval, len))
3281 val = sizeof(struct tpacket_hdr);
3284 val = sizeof(struct tpacket2_hdr);
3287 val = sizeof(struct tpacket3_hdr);
3293 case PACKET_RESERVE:
3294 val = po->tp_reserve;
3299 case PACKET_TIMESTAMP:
3300 val = po->tp_tstamp;
3304 ((u32)po->fanout->id |
3305 ((u32)po->fanout->type << 16) |
3306 ((u32)po->fanout->flags << 24)) :
3309 case PACKET_TX_HAS_OFF:
3310 val = po->tp_tx_has_off;
3313 return -ENOPROTOOPT;
3318 if (put_user(len, optlen))
3320 if (copy_to_user(optval, data, len))
3326 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
3329 struct net_device *dev = data;
3330 struct net *net = dev_net(dev);
3333 sk_for_each_rcu(sk, &net->packet.sklist) {
3334 struct packet_sock *po = pkt_sk(sk);
3337 case NETDEV_UNREGISTER:
3339 packet_dev_mclist(dev, po->mclist, -1);
3343 if (dev->ifindex == po->ifindex) {
3344 spin_lock(&po->bind_lock);
3346 __unregister_prot_hook(sk, false);
3347 sk->sk_err = ENETDOWN;
3348 if (!sock_flag(sk, SOCK_DEAD))
3349 sk->sk_error_report(sk);
3351 if (msg == NETDEV_UNREGISTER) {
3353 if (po->prot_hook.dev)
3354 dev_put(po->prot_hook.dev);
3355 po->prot_hook.dev = NULL;
3357 spin_unlock(&po->bind_lock);
3361 if (dev->ifindex == po->ifindex) {
3362 spin_lock(&po->bind_lock);
3364 register_prot_hook(sk);
3365 spin_unlock(&po->bind_lock);
3375 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3378 struct sock *sk = sock->sk;
3383 int amount = sk_wmem_alloc_get(sk);
3385 return put_user(amount, (int __user *)arg);
3389 struct sk_buff *skb;
3392 spin_lock_bh(&sk->sk_receive_queue.lock);
3393 skb = skb_peek(&sk->sk_receive_queue);
3396 spin_unlock_bh(&sk->sk_receive_queue.lock);
3397 return put_user(amount, (int __user *)arg);
3400 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3402 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3412 case SIOCGIFBRDADDR:
3413 case SIOCSIFBRDADDR:
3414 case SIOCGIFNETMASK:
3415 case SIOCSIFNETMASK:
3416 case SIOCGIFDSTADDR:
3417 case SIOCSIFDSTADDR:
3419 return inet_dgram_ops.ioctl(sock, cmd, arg);
3423 return -ENOIOCTLCMD;
3428 static unsigned int packet_poll(struct file *file, struct socket *sock,
3431 struct sock *sk = sock->sk;
3432 struct packet_sock *po = pkt_sk(sk);
3433 unsigned int mask = datagram_poll(file, sock, wait);
3435 spin_lock_bh(&sk->sk_receive_queue.lock);
3436 if (po->rx_ring.pg_vec) {
3437 if (!packet_previous_rx_frame(po, &po->rx_ring,
3439 mask |= POLLIN | POLLRDNORM;
3441 spin_unlock_bh(&sk->sk_receive_queue.lock);
3442 spin_lock_bh(&sk->sk_write_queue.lock);
3443 if (po->tx_ring.pg_vec) {
3444 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3445 mask |= POLLOUT | POLLWRNORM;
3447 spin_unlock_bh(&sk->sk_write_queue.lock);
3452 /* Dirty? Well, I still did not learn better way to account
3456 static void packet_mm_open(struct vm_area_struct *vma)
3458 struct file *file = vma->vm_file;
3459 struct socket *sock = file->private_data;
3460 struct sock *sk = sock->sk;
3463 atomic_inc(&pkt_sk(sk)->mapped);
3466 static void packet_mm_close(struct vm_area_struct *vma)
3468 struct file *file = vma->vm_file;
3469 struct socket *sock = file->private_data;
3470 struct sock *sk = sock->sk;
3473 atomic_dec(&pkt_sk(sk)->mapped);
3476 static const struct vm_operations_struct packet_mmap_ops = {
3477 .open = packet_mm_open,
3478 .close = packet_mm_close,
3481 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3486 for (i = 0; i < len; i++) {
3487 if (likely(pg_vec[i].buffer)) {
3488 if (is_vmalloc_addr(pg_vec[i].buffer))
3489 vfree(pg_vec[i].buffer);
3491 free_pages((unsigned long)pg_vec[i].buffer,
3493 pg_vec[i].buffer = NULL;
3499 static char *alloc_one_pg_vec_page(unsigned long order)
3501 char *buffer = NULL;
3502 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3503 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3505 buffer = (char *) __get_free_pages(gfp_flags, order);
3511 * __get_free_pages failed, fall back to vmalloc
3513 buffer = vzalloc((1 << order) * PAGE_SIZE);
3519 * vmalloc failed, lets dig into swap here
3521 gfp_flags &= ~__GFP_NORETRY;
3522 buffer = (char *)__get_free_pages(gfp_flags, order);
3527 * complete and utter failure
3532 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3534 unsigned int block_nr = req->tp_block_nr;
3538 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3539 if (unlikely(!pg_vec))
3542 for (i = 0; i < block_nr; i++) {
3543 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3544 if (unlikely(!pg_vec[i].buffer))
3545 goto out_free_pgvec;
3552 free_pg_vec(pg_vec, order, block_nr);
3557 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3558 int closing, int tx_ring)
3560 struct pgv *pg_vec = NULL;
3561 struct packet_sock *po = pkt_sk(sk);
3562 int was_running, order = 0;
3563 struct packet_ring_buffer *rb;
3564 struct sk_buff_head *rb_queue;
3567 /* Added to avoid minimal code churn */
3568 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))
3649 /* Detach socket from network */
3650 spin_lock(&po->bind_lock);
3651 was_running = po->running;
3655 __unregister_prot_hook(sk, false);
3657 spin_unlock(&po->bind_lock);
3662 mutex_lock(&po->pg_vec_lock);
3663 if (closing || atomic_read(&po->mapped) == 0) {
3665 spin_lock_bh(&rb_queue->lock);
3666 swap(rb->pg_vec, pg_vec);
3667 rb->frame_max = (req->tp_frame_nr - 1);
3669 rb->frame_size = req->tp_frame_size;
3670 spin_unlock_bh(&rb_queue->lock);
3672 swap(rb->pg_vec_order, order);
3673 swap(rb->pg_vec_len, req->tp_block_nr);
3675 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3676 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3677 tpacket_rcv : packet_rcv;
3678 skb_queue_purge(rb_queue);
3679 if (atomic_read(&po->mapped))
3680 pr_err("packet_mmap: vma is busy: %d\n",
3681 atomic_read(&po->mapped));
3683 mutex_unlock(&po->pg_vec_lock);
3685 spin_lock(&po->bind_lock);
3688 register_prot_hook(sk);
3690 spin_unlock(&po->bind_lock);
3691 if (closing && (po->tp_version > TPACKET_V2)) {
3692 /* Because we don't support block-based V3 on tx-ring */
3694 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3699 free_pg_vec(pg_vec, order, req->tp_block_nr);
3704 static int packet_mmap(struct file *file, struct socket *sock,
3705 struct vm_area_struct *vma)
3707 struct sock *sk = sock->sk;
3708 struct packet_sock *po = pkt_sk(sk);
3709 unsigned long size, expected_size;
3710 struct packet_ring_buffer *rb;
3711 unsigned long start;
3718 mutex_lock(&po->pg_vec_lock);
3721 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3723 expected_size += rb->pg_vec_len
3729 if (expected_size == 0)
3732 size = vma->vm_end - vma->vm_start;
3733 if (size != expected_size)
3736 start = vma->vm_start;
3737 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3738 if (rb->pg_vec == NULL)
3741 for (i = 0; i < rb->pg_vec_len; i++) {
3743 void *kaddr = rb->pg_vec[i].buffer;
3746 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3747 page = pgv_to_page(kaddr);
3748 err = vm_insert_page(vma, start, page);
3757 atomic_inc(&po->mapped);
3758 vma->vm_ops = &packet_mmap_ops;
3762 mutex_unlock(&po->pg_vec_lock);
3766 static const struct proto_ops packet_ops_spkt = {
3767 .family = PF_PACKET,
3768 .owner = THIS_MODULE,
3769 .release = packet_release,
3770 .bind = packet_bind_spkt,
3771 .connect = sock_no_connect,
3772 .socketpair = sock_no_socketpair,
3773 .accept = sock_no_accept,
3774 .getname = packet_getname_spkt,
3775 .poll = datagram_poll,
3776 .ioctl = packet_ioctl,
3777 .listen = sock_no_listen,
3778 .shutdown = sock_no_shutdown,
3779 .setsockopt = sock_no_setsockopt,
3780 .getsockopt = sock_no_getsockopt,
3781 .sendmsg = packet_sendmsg_spkt,
3782 .recvmsg = packet_recvmsg,
3783 .mmap = sock_no_mmap,
3784 .sendpage = sock_no_sendpage,
3787 static const struct proto_ops packet_ops = {
3788 .family = PF_PACKET,
3789 .owner = THIS_MODULE,
3790 .release = packet_release,
3791 .bind = packet_bind,
3792 .connect = sock_no_connect,
3793 .socketpair = sock_no_socketpair,
3794 .accept = sock_no_accept,
3795 .getname = packet_getname,
3796 .poll = packet_poll,
3797 .ioctl = packet_ioctl,
3798 .listen = sock_no_listen,
3799 .shutdown = sock_no_shutdown,
3800 .setsockopt = packet_setsockopt,
3801 .getsockopt = packet_getsockopt,
3802 .sendmsg = packet_sendmsg,
3803 .recvmsg = packet_recvmsg,
3804 .mmap = packet_mmap,
3805 .sendpage = sock_no_sendpage,
3808 static const struct net_proto_family packet_family_ops = {
3809 .family = PF_PACKET,
3810 .create = packet_create,
3811 .owner = THIS_MODULE,
3814 static struct notifier_block packet_netdev_notifier = {
3815 .notifier_call = packet_notifier,
3818 #ifdef CONFIG_PROC_FS
3820 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3823 struct net *net = seq_file_net(seq);
3826 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3829 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3831 struct net *net = seq_file_net(seq);
3832 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
3835 static void packet_seq_stop(struct seq_file *seq, void *v)
3841 static int packet_seq_show(struct seq_file *seq, void *v)
3843 if (v == SEQ_START_TOKEN)
3844 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
3846 struct sock *s = sk_entry(v);
3847 const struct packet_sock *po = pkt_sk(s);
3850 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
3852 atomic_read(&s->sk_refcnt),
3857 atomic_read(&s->sk_rmem_alloc),
3858 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
3865 static const struct seq_operations packet_seq_ops = {
3866 .start = packet_seq_start,
3867 .next = packet_seq_next,
3868 .stop = packet_seq_stop,
3869 .show = packet_seq_show,
3872 static int packet_seq_open(struct inode *inode, struct file *file)
3874 return seq_open_net(inode, file, &packet_seq_ops,
3875 sizeof(struct seq_net_private));
3878 static const struct file_operations packet_seq_fops = {
3879 .owner = THIS_MODULE,
3880 .open = packet_seq_open,
3882 .llseek = seq_lseek,
3883 .release = seq_release_net,
3888 static int __net_init packet_net_init(struct net *net)
3890 mutex_init(&net->packet.sklist_lock);
3891 INIT_HLIST_HEAD(&net->packet.sklist);
3893 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
3899 static void __net_exit packet_net_exit(struct net *net)
3901 remove_proc_entry("packet", net->proc_net);
3904 static struct pernet_operations packet_net_ops = {
3905 .init = packet_net_init,
3906 .exit = packet_net_exit,
3910 static void __exit packet_exit(void)
3912 unregister_netdevice_notifier(&packet_netdev_notifier);
3913 unregister_pernet_subsys(&packet_net_ops);
3914 sock_unregister(PF_PACKET);
3915 proto_unregister(&packet_proto);
3918 static int __init packet_init(void)
3920 int rc = proto_register(&packet_proto, 0);
3925 sock_register(&packet_family_ops);
3926 register_pernet_subsys(&packet_net_ops);
3927 register_netdevice_notifier(&packet_netdev_notifier);
3932 module_init(packet_init);
3933 module_exit(packet_exit);
3934 MODULE_LICENSE("GPL");
3935 MODULE_ALIAS_NETPROTO(PF_PACKET);