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>
91 #include <linux/percpu.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];
162 struct tpacket_hdr *h1;
163 struct tpacket2_hdr *h2;
164 struct tpacket3_hdr *h3;
168 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
169 int closing, int tx_ring);
171 #define V3_ALIGNMENT (8)
173 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
175 #define BLK_PLUS_PRIV(sz_of_priv) \
176 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
178 #define PGV_FROM_VMALLOC 1
180 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
181 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
182 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
183 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
184 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
185 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
186 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
189 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
190 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
191 struct packet_type *pt, struct net_device *orig_dev);
193 static void *packet_previous_frame(struct packet_sock *po,
194 struct packet_ring_buffer *rb,
196 static void packet_increment_head(struct packet_ring_buffer *buff);
197 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
198 struct tpacket_block_desc *);
199 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
200 struct packet_sock *);
201 static void prb_retire_current_block(struct tpacket_kbdq_core *,
202 struct packet_sock *, unsigned int status);
203 static int prb_queue_frozen(struct tpacket_kbdq_core *);
204 static void prb_open_block(struct tpacket_kbdq_core *,
205 struct tpacket_block_desc *);
206 static void prb_retire_rx_blk_timer_expired(unsigned long);
207 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
208 static void prb_init_blk_timer(struct packet_sock *,
209 struct tpacket_kbdq_core *,
210 void (*func) (unsigned long));
211 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
212 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
213 struct tpacket3_hdr *);
214 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
215 struct tpacket3_hdr *);
216 static void packet_flush_mclist(struct sock *sk);
218 struct packet_skb_cb {
219 unsigned int origlen;
221 struct sockaddr_pkt pkt;
222 struct sockaddr_ll ll;
226 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
228 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
229 #define GET_PBLOCK_DESC(x, bid) \
230 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
231 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
232 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
233 #define GET_NEXT_PRB_BLK_NUM(x) \
234 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
235 ((x)->kactive_blk_num+1) : 0)
237 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
238 static void __fanout_link(struct sock *sk, struct packet_sock *po);
240 static int packet_direct_xmit(struct sk_buff *skb)
242 struct net_device *dev = skb->dev;
243 netdev_features_t features;
244 struct netdev_queue *txq;
245 int ret = NETDEV_TX_BUSY;
247 if (unlikely(!netif_running(dev) ||
248 !netif_carrier_ok(dev)))
251 features = netif_skb_features(skb);
252 if (skb_needs_linearize(skb, features) &&
253 __skb_linearize(skb))
256 txq = skb_get_tx_queue(dev, skb);
260 HARD_TX_LOCK(dev, txq, smp_processor_id());
261 if (!netif_xmit_frozen_or_drv_stopped(txq))
262 ret = netdev_start_xmit(skb, dev, txq, false);
263 HARD_TX_UNLOCK(dev, txq);
267 if (!dev_xmit_complete(ret))
272 atomic_long_inc(&dev->tx_dropped);
274 return NET_XMIT_DROP;
277 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
279 struct net_device *dev;
282 dev = rcu_dereference(po->cached_dev);
290 static void packet_cached_dev_assign(struct packet_sock *po,
291 struct net_device *dev)
293 rcu_assign_pointer(po->cached_dev, dev);
296 static void packet_cached_dev_reset(struct packet_sock *po)
298 RCU_INIT_POINTER(po->cached_dev, NULL);
301 static bool packet_use_direct_xmit(const struct packet_sock *po)
303 return po->xmit == packet_direct_xmit;
306 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
308 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
311 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
313 const struct net_device_ops *ops = dev->netdev_ops;
316 if (ops->ndo_select_queue) {
317 queue_index = ops->ndo_select_queue(dev, skb, NULL,
318 __packet_pick_tx_queue);
319 queue_index = netdev_cap_txqueue(dev, queue_index);
321 queue_index = __packet_pick_tx_queue(dev, skb);
324 skb_set_queue_mapping(skb, queue_index);
327 /* register_prot_hook must be invoked with the po->bind_lock held,
328 * or from a context in which asynchronous accesses to the packet
329 * socket is not possible (packet_create()).
331 static void register_prot_hook(struct sock *sk)
333 struct packet_sock *po = pkt_sk(sk);
337 __fanout_link(sk, po);
339 dev_add_pack(&po->prot_hook);
346 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
347 * held. If the sync parameter is true, we will temporarily drop
348 * the po->bind_lock and do a synchronize_net to make sure no
349 * asynchronous packet processing paths still refer to the elements
350 * of po->prot_hook. If the sync parameter is false, it is the
351 * callers responsibility to take care of this.
353 static void __unregister_prot_hook(struct sock *sk, bool sync)
355 struct packet_sock *po = pkt_sk(sk);
360 __fanout_unlink(sk, po);
362 __dev_remove_pack(&po->prot_hook);
367 spin_unlock(&po->bind_lock);
369 spin_lock(&po->bind_lock);
373 static void unregister_prot_hook(struct sock *sk, bool sync)
375 struct packet_sock *po = pkt_sk(sk);
378 __unregister_prot_hook(sk, sync);
381 static inline struct page * __pure pgv_to_page(void *addr)
383 if (is_vmalloc_addr(addr))
384 return vmalloc_to_page(addr);
385 return virt_to_page(addr);
388 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
390 union tpacket_uhdr h;
393 switch (po->tp_version) {
395 h.h1->tp_status = status;
396 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
399 h.h2->tp_status = status;
400 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
404 WARN(1, "TPACKET version not supported.\n");
411 static int __packet_get_status(struct packet_sock *po, void *frame)
413 union tpacket_uhdr h;
418 switch (po->tp_version) {
420 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
421 return h.h1->tp_status;
423 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
424 return h.h2->tp_status;
427 WARN(1, "TPACKET version not supported.\n");
433 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
436 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
439 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
440 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
441 return TP_STATUS_TS_RAW_HARDWARE;
443 if (ktime_to_timespec_cond(skb->tstamp, ts))
444 return TP_STATUS_TS_SOFTWARE;
449 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
452 union tpacket_uhdr h;
456 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
460 switch (po->tp_version) {
462 h.h1->tp_sec = ts.tv_sec;
463 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
466 h.h2->tp_sec = ts.tv_sec;
467 h.h2->tp_nsec = ts.tv_nsec;
471 WARN(1, "TPACKET version not supported.\n");
475 /* one flush is safe, as both fields always lie on the same cacheline */
476 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
482 static void *packet_lookup_frame(struct packet_sock *po,
483 struct packet_ring_buffer *rb,
484 unsigned int position,
487 unsigned int pg_vec_pos, frame_offset;
488 union tpacket_uhdr h;
490 pg_vec_pos = position / rb->frames_per_block;
491 frame_offset = position % rb->frames_per_block;
493 h.raw = rb->pg_vec[pg_vec_pos].buffer +
494 (frame_offset * rb->frame_size);
496 if (status != __packet_get_status(po, h.raw))
502 static void *packet_current_frame(struct packet_sock *po,
503 struct packet_ring_buffer *rb,
506 return packet_lookup_frame(po, rb, rb->head, status);
509 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
511 del_timer_sync(&pkc->retire_blk_timer);
514 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
516 struct sk_buff_head *rb_queue)
518 struct tpacket_kbdq_core *pkc;
520 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
521 GET_PBDQC_FROM_RB(&po->rx_ring);
523 spin_lock_bh(&rb_queue->lock);
524 pkc->delete_blk_timer = 1;
525 spin_unlock_bh(&rb_queue->lock);
527 prb_del_retire_blk_timer(pkc);
530 static void prb_init_blk_timer(struct packet_sock *po,
531 struct tpacket_kbdq_core *pkc,
532 void (*func) (unsigned long))
534 init_timer(&pkc->retire_blk_timer);
535 pkc->retire_blk_timer.data = (long)po;
536 pkc->retire_blk_timer.function = func;
537 pkc->retire_blk_timer.expires = jiffies;
540 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
542 struct tpacket_kbdq_core *pkc;
547 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
548 GET_PBDQC_FROM_RB(&po->rx_ring);
549 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
552 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
553 int blk_size_in_bytes)
555 struct net_device *dev;
556 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
557 struct ethtool_cmd ecmd;
562 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
563 if (unlikely(!dev)) {
565 return DEFAULT_PRB_RETIRE_TOV;
567 err = __ethtool_get_settings(dev, &ecmd);
568 speed = ethtool_cmd_speed(&ecmd);
572 * If the link speed is so slow you don't really
573 * need to worry about perf anyways
575 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
576 return DEFAULT_PRB_RETIRE_TOV;
583 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
595 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
596 union tpacket_req_u *req_u)
598 p1->feature_req_word = req_u->req3.tp_feature_req_word;
601 static void init_prb_bdqc(struct packet_sock *po,
602 struct packet_ring_buffer *rb,
604 union tpacket_req_u *req_u, int tx_ring)
606 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
607 struct tpacket_block_desc *pbd;
609 memset(p1, 0x0, sizeof(*p1));
611 p1->knxt_seq_num = 1;
613 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
614 p1->pkblk_start = pg_vec[0].buffer;
615 p1->kblk_size = req_u->req3.tp_block_size;
616 p1->knum_blocks = req_u->req3.tp_block_nr;
617 p1->hdrlen = po->tp_hdrlen;
618 p1->version = po->tp_version;
619 p1->last_kactive_blk_num = 0;
620 po->stats.stats3.tp_freeze_q_cnt = 0;
621 if (req_u->req3.tp_retire_blk_tov)
622 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
624 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
625 req_u->req3.tp_block_size);
626 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
627 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
629 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
630 prb_init_ft_ops(p1, req_u);
631 prb_setup_retire_blk_timer(po, tx_ring);
632 prb_open_block(p1, pbd);
635 /* Do NOT update the last_blk_num first.
636 * Assumes sk_buff_head lock is held.
638 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
640 mod_timer(&pkc->retire_blk_timer,
641 jiffies + pkc->tov_in_jiffies);
642 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
647 * 1) We refresh the timer only when we open a block.
648 * By doing this we don't waste cycles refreshing the timer
649 * on packet-by-packet basis.
651 * With a 1MB block-size, on a 1Gbps line, it will take
652 * i) ~8 ms to fill a block + ii) memcpy etc.
653 * In this cut we are not accounting for the memcpy time.
655 * So, if the user sets the 'tmo' to 10ms then the timer
656 * will never fire while the block is still getting filled
657 * (which is what we want). However, the user could choose
658 * to close a block early and that's fine.
660 * But when the timer does fire, we check whether or not to refresh it.
661 * Since the tmo granularity is in msecs, it is not too expensive
662 * to refresh the timer, lets say every '8' msecs.
663 * Either the user can set the 'tmo' or we can derive it based on
664 * a) line-speed and b) block-size.
665 * prb_calc_retire_blk_tmo() calculates the tmo.
668 static void prb_retire_rx_blk_timer_expired(unsigned long data)
670 struct packet_sock *po = (struct packet_sock *)data;
671 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
673 struct tpacket_block_desc *pbd;
675 spin_lock(&po->sk.sk_receive_queue.lock);
677 frozen = prb_queue_frozen(pkc);
678 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
680 if (unlikely(pkc->delete_blk_timer))
683 /* We only need to plug the race when the block is partially filled.
685 * lock(); increment BLOCK_NUM_PKTS; unlock()
686 * copy_bits() is in progress ...
687 * timer fires on other cpu:
688 * we can't retire the current block because copy_bits
692 if (BLOCK_NUM_PKTS(pbd)) {
693 while (atomic_read(&pkc->blk_fill_in_prog)) {
694 /* Waiting for skb_copy_bits to finish... */
699 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
701 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
702 if (!prb_dispatch_next_block(pkc, po))
707 /* Case 1. Queue was frozen because user-space was
710 if (prb_curr_blk_in_use(pkc, pbd)) {
712 * Ok, user-space is still behind.
713 * So just refresh the timer.
717 /* Case 2. queue was frozen,user-space caught up,
718 * now the link went idle && the timer fired.
719 * We don't have a block to close.So we open this
720 * block and restart the timer.
721 * opening a block thaws the queue,restarts timer
722 * Thawing/timer-refresh is a side effect.
724 prb_open_block(pkc, pbd);
731 _prb_refresh_rx_retire_blk_timer(pkc);
734 spin_unlock(&po->sk.sk_receive_queue.lock);
737 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
738 struct tpacket_block_desc *pbd1, __u32 status)
740 /* Flush everything minus the block header */
742 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
747 /* Skip the block header(we know header WILL fit in 4K) */
750 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
751 for (; start < end; start += PAGE_SIZE)
752 flush_dcache_page(pgv_to_page(start));
757 /* Now update the block status. */
759 BLOCK_STATUS(pbd1) = status;
761 /* Flush the block header */
763 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
765 flush_dcache_page(pgv_to_page(start));
775 * 2) Increment active_blk_num
777 * Note:We DONT refresh the timer on purpose.
778 * Because almost always the next block will be opened.
780 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
781 struct tpacket_block_desc *pbd1,
782 struct packet_sock *po, unsigned int stat)
784 __u32 status = TP_STATUS_USER | stat;
786 struct tpacket3_hdr *last_pkt;
787 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
789 if (po->stats.stats3.tp_drops)
790 status |= TP_STATUS_LOSING;
792 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
793 last_pkt->tp_next_offset = 0;
795 /* Get the ts of the last pkt */
796 if (BLOCK_NUM_PKTS(pbd1)) {
797 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
798 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
800 /* Ok, we tmo'd - so get the current time */
803 h1->ts_last_pkt.ts_sec = ts.tv_sec;
804 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
809 /* Flush the block */
810 prb_flush_block(pkc1, pbd1, status);
812 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
815 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
817 pkc->reset_pending_on_curr_blk = 0;
821 * Side effect of opening a block:
823 * 1) prb_queue is thawed.
824 * 2) retire_blk_timer is refreshed.
827 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
828 struct tpacket_block_desc *pbd1)
831 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
835 /* We could have just memset this but we will lose the
836 * flexibility of making the priv area sticky
839 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
840 BLOCK_NUM_PKTS(pbd1) = 0;
841 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
845 h1->ts_first_pkt.ts_sec = ts.tv_sec;
846 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
848 pkc1->pkblk_start = (char *)pbd1;
849 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
851 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
852 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
854 pbd1->version = pkc1->version;
855 pkc1->prev = pkc1->nxt_offset;
856 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
858 prb_thaw_queue(pkc1);
859 _prb_refresh_rx_retire_blk_timer(pkc1);
865 * Queue freeze logic:
866 * 1) Assume tp_block_nr = 8 blocks.
867 * 2) At time 't0', user opens Rx ring.
868 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
869 * 4) user-space is either sleeping or processing block '0'.
870 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
871 * it will close block-7,loop around and try to fill block '0'.
873 * __packet_lookup_frame_in_block
874 * prb_retire_current_block()
875 * prb_dispatch_next_block()
876 * |->(BLOCK_STATUS == USER) evaluates to true
877 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
878 * 6) Now there are two cases:
879 * 6.1) Link goes idle right after the queue is frozen.
880 * But remember, the last open_block() refreshed the timer.
881 * When this timer expires,it will refresh itself so that we can
882 * re-open block-0 in near future.
883 * 6.2) Link is busy and keeps on receiving packets. This is a simple
884 * case and __packet_lookup_frame_in_block will check if block-0
885 * is free and can now be re-used.
887 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
888 struct packet_sock *po)
890 pkc->reset_pending_on_curr_blk = 1;
891 po->stats.stats3.tp_freeze_q_cnt++;
894 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
897 * If the next block is free then we will dispatch it
898 * and return a good offset.
899 * Else, we will freeze the queue.
900 * So, caller must check the return value.
902 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
903 struct packet_sock *po)
905 struct tpacket_block_desc *pbd;
909 /* 1. Get current block num */
910 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
912 /* 2. If this block is currently in_use then freeze the queue */
913 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
914 prb_freeze_queue(pkc, po);
920 * open this block and return the offset where the first packet
921 * needs to get stored.
923 prb_open_block(pkc, pbd);
924 return (void *)pkc->nxt_offset;
927 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
928 struct packet_sock *po, unsigned int status)
930 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
932 /* retire/close the current block */
933 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
935 * Plug the case where copy_bits() is in progress on
936 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
937 * have space to copy the pkt in the current block and
938 * called prb_retire_current_block()
940 * We don't need to worry about the TMO case because
941 * the timer-handler already handled this case.
943 if (!(status & TP_STATUS_BLK_TMO)) {
944 while (atomic_read(&pkc->blk_fill_in_prog)) {
945 /* Waiting for skb_copy_bits to finish... */
949 prb_close_block(pkc, pbd, po, status);
954 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
955 struct tpacket_block_desc *pbd)
957 return TP_STATUS_USER & BLOCK_STATUS(pbd);
960 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
962 return pkc->reset_pending_on_curr_blk;
965 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
967 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
968 atomic_dec(&pkc->blk_fill_in_prog);
971 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
972 struct tpacket3_hdr *ppd)
974 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
977 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
978 struct tpacket3_hdr *ppd)
980 ppd->hv1.tp_rxhash = 0;
983 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
984 struct tpacket3_hdr *ppd)
986 if (vlan_tx_tag_present(pkc->skb)) {
987 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
988 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
989 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
991 ppd->hv1.tp_vlan_tci = 0;
992 ppd->hv1.tp_vlan_tpid = 0;
993 ppd->tp_status = TP_STATUS_AVAILABLE;
997 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
998 struct tpacket3_hdr *ppd)
1000 ppd->hv1.tp_padding = 0;
1001 prb_fill_vlan_info(pkc, ppd);
1003 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1004 prb_fill_rxhash(pkc, ppd);
1006 prb_clear_rxhash(pkc, ppd);
1009 static void prb_fill_curr_block(char *curr,
1010 struct tpacket_kbdq_core *pkc,
1011 struct tpacket_block_desc *pbd,
1014 struct tpacket3_hdr *ppd;
1016 ppd = (struct tpacket3_hdr *)curr;
1017 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1019 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1020 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1021 BLOCK_NUM_PKTS(pbd) += 1;
1022 atomic_inc(&pkc->blk_fill_in_prog);
1023 prb_run_all_ft_ops(pkc, ppd);
1026 /* Assumes caller has the sk->rx_queue.lock */
1027 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1028 struct sk_buff *skb,
1033 struct tpacket_kbdq_core *pkc;
1034 struct tpacket_block_desc *pbd;
1037 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1038 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1040 /* Queue is frozen when user space is lagging behind */
1041 if (prb_queue_frozen(pkc)) {
1043 * Check if that last block which caused the queue to freeze,
1044 * is still in_use by user-space.
1046 if (prb_curr_blk_in_use(pkc, pbd)) {
1047 /* Can't record this packet */
1051 * Ok, the block was released by user-space.
1052 * Now let's open that block.
1053 * opening a block also thaws the queue.
1054 * Thawing is a side effect.
1056 prb_open_block(pkc, pbd);
1061 curr = pkc->nxt_offset;
1063 end = (char *)pbd + pkc->kblk_size;
1065 /* first try the current block */
1066 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1067 prb_fill_curr_block(curr, pkc, pbd, len);
1068 return (void *)curr;
1071 /* Ok, close the current block */
1072 prb_retire_current_block(pkc, po, 0);
1074 /* Now, try to dispatch the next block */
1075 curr = (char *)prb_dispatch_next_block(pkc, po);
1077 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1078 prb_fill_curr_block(curr, pkc, pbd, len);
1079 return (void *)curr;
1083 * No free blocks are available.user_space hasn't caught up yet.
1084 * Queue was just frozen and now this packet will get dropped.
1089 static void *packet_current_rx_frame(struct packet_sock *po,
1090 struct sk_buff *skb,
1091 int status, unsigned int len)
1094 switch (po->tp_version) {
1097 curr = packet_lookup_frame(po, &po->rx_ring,
1098 po->rx_ring.head, status);
1101 return __packet_lookup_frame_in_block(po, skb, status, len);
1103 WARN(1, "TPACKET version not supported\n");
1109 static void *prb_lookup_block(struct packet_sock *po,
1110 struct packet_ring_buffer *rb,
1114 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1115 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1117 if (status != BLOCK_STATUS(pbd))
1122 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1125 if (rb->prb_bdqc.kactive_blk_num)
1126 prev = rb->prb_bdqc.kactive_blk_num-1;
1128 prev = rb->prb_bdqc.knum_blocks-1;
1132 /* Assumes caller has held the rx_queue.lock */
1133 static void *__prb_previous_block(struct packet_sock *po,
1134 struct packet_ring_buffer *rb,
1137 unsigned int previous = prb_previous_blk_num(rb);
1138 return prb_lookup_block(po, rb, previous, status);
1141 static void *packet_previous_rx_frame(struct packet_sock *po,
1142 struct packet_ring_buffer *rb,
1145 if (po->tp_version <= TPACKET_V2)
1146 return packet_previous_frame(po, rb, status);
1148 return __prb_previous_block(po, rb, status);
1151 static void packet_increment_rx_head(struct packet_sock *po,
1152 struct packet_ring_buffer *rb)
1154 switch (po->tp_version) {
1157 return packet_increment_head(rb);
1160 WARN(1, "TPACKET version not supported.\n");
1166 static void *packet_previous_frame(struct packet_sock *po,
1167 struct packet_ring_buffer *rb,
1170 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1171 return packet_lookup_frame(po, rb, previous, status);
1174 static void packet_increment_head(struct packet_ring_buffer *buff)
1176 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1179 static void packet_inc_pending(struct packet_ring_buffer *rb)
1181 this_cpu_inc(*rb->pending_refcnt);
1184 static void packet_dec_pending(struct packet_ring_buffer *rb)
1186 this_cpu_dec(*rb->pending_refcnt);
1189 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1191 unsigned int refcnt = 0;
1194 /* We don't use pending refcount in rx_ring. */
1195 if (rb->pending_refcnt == NULL)
1198 for_each_possible_cpu(cpu)
1199 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1204 static int packet_alloc_pending(struct packet_sock *po)
1206 po->rx_ring.pending_refcnt = NULL;
1208 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1209 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1215 static void packet_free_pending(struct packet_sock *po)
1217 free_percpu(po->tx_ring.pending_refcnt);
1220 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1222 struct sock *sk = &po->sk;
1225 if (po->prot_hook.func != tpacket_rcv)
1226 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1229 spin_lock(&sk->sk_receive_queue.lock);
1230 if (po->tp_version == TPACKET_V3)
1231 has_room = prb_lookup_block(po, &po->rx_ring,
1232 po->rx_ring.prb_bdqc.kactive_blk_num,
1235 has_room = packet_lookup_frame(po, &po->rx_ring,
1238 spin_unlock(&sk->sk_receive_queue.lock);
1243 static void packet_sock_destruct(struct sock *sk)
1245 skb_queue_purge(&sk->sk_error_queue);
1247 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1248 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1250 if (!sock_flag(sk, SOCK_DEAD)) {
1251 pr_err("Attempt to release alive packet socket: %p\n", sk);
1255 sk_refcnt_debug_dec(sk);
1258 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1260 int x = atomic_read(&f->rr_cur) + 1;
1268 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1269 struct sk_buff *skb,
1272 return reciprocal_scale(skb_get_hash(skb), num);
1275 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1276 struct sk_buff *skb,
1281 cur = atomic_read(&f->rr_cur);
1282 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1283 fanout_rr_next(f, num))) != cur)
1288 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1289 struct sk_buff *skb,
1292 return smp_processor_id() % num;
1295 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1296 struct sk_buff *skb,
1299 return prandom_u32_max(num);
1302 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1303 struct sk_buff *skb,
1304 unsigned int idx, unsigned int skip,
1309 i = j = min_t(int, f->next[idx], num - 1);
1311 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1323 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1324 struct sk_buff *skb,
1327 return skb_get_queue_mapping(skb) % num;
1330 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1332 return f->flags & (flag >> 8);
1335 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1336 struct packet_type *pt, struct net_device *orig_dev)
1338 struct packet_fanout *f = pt->af_packet_priv;
1339 unsigned int num = f->num_members;
1340 struct packet_sock *po;
1343 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1350 case PACKET_FANOUT_HASH:
1352 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1353 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1357 idx = fanout_demux_hash(f, skb, num);
1359 case PACKET_FANOUT_LB:
1360 idx = fanout_demux_lb(f, skb, num);
1362 case PACKET_FANOUT_CPU:
1363 idx = fanout_demux_cpu(f, skb, num);
1365 case PACKET_FANOUT_RND:
1366 idx = fanout_demux_rnd(f, skb, num);
1368 case PACKET_FANOUT_QM:
1369 idx = fanout_demux_qm(f, skb, num);
1371 case PACKET_FANOUT_ROLLOVER:
1372 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1376 po = pkt_sk(f->arr[idx]);
1377 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1378 unlikely(!packet_rcv_has_room(po, skb))) {
1379 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1380 po = pkt_sk(f->arr[idx]);
1383 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1386 DEFINE_MUTEX(fanout_mutex);
1387 EXPORT_SYMBOL_GPL(fanout_mutex);
1388 static LIST_HEAD(fanout_list);
1390 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1392 struct packet_fanout *f = po->fanout;
1394 spin_lock(&f->lock);
1395 f->arr[f->num_members] = sk;
1398 spin_unlock(&f->lock);
1401 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1403 struct packet_fanout *f = po->fanout;
1406 spin_lock(&f->lock);
1407 for (i = 0; i < f->num_members; i++) {
1408 if (f->arr[i] == sk)
1411 BUG_ON(i >= f->num_members);
1412 f->arr[i] = f->arr[f->num_members - 1];
1414 spin_unlock(&f->lock);
1417 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1419 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1425 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1427 struct packet_sock *po = pkt_sk(sk);
1428 struct packet_fanout *f, *match;
1429 u8 type = type_flags & 0xff;
1430 u8 flags = type_flags >> 8;
1434 case PACKET_FANOUT_ROLLOVER:
1435 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1437 case PACKET_FANOUT_HASH:
1438 case PACKET_FANOUT_LB:
1439 case PACKET_FANOUT_CPU:
1440 case PACKET_FANOUT_RND:
1441 case PACKET_FANOUT_QM:
1453 mutex_lock(&fanout_mutex);
1455 list_for_each_entry(f, &fanout_list, list) {
1457 read_pnet(&f->net) == sock_net(sk)) {
1463 if (match && match->flags != flags)
1467 match = kzalloc(sizeof(*match), GFP_KERNEL);
1470 write_pnet(&match->net, sock_net(sk));
1473 match->flags = flags;
1474 atomic_set(&match->rr_cur, 0);
1475 INIT_LIST_HEAD(&match->list);
1476 spin_lock_init(&match->lock);
1477 atomic_set(&match->sk_ref, 0);
1478 match->prot_hook.type = po->prot_hook.type;
1479 match->prot_hook.dev = po->prot_hook.dev;
1480 match->prot_hook.func = packet_rcv_fanout;
1481 match->prot_hook.af_packet_priv = match;
1482 match->prot_hook.id_match = match_fanout_group;
1483 dev_add_pack(&match->prot_hook);
1484 list_add(&match->list, &fanout_list);
1487 if (match->type == type &&
1488 match->prot_hook.type == po->prot_hook.type &&
1489 match->prot_hook.dev == po->prot_hook.dev) {
1491 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1492 __dev_remove_pack(&po->prot_hook);
1494 atomic_inc(&match->sk_ref);
1495 __fanout_link(sk, po);
1500 mutex_unlock(&fanout_mutex);
1504 static void fanout_release(struct sock *sk)
1506 struct packet_sock *po = pkt_sk(sk);
1507 struct packet_fanout *f;
1513 mutex_lock(&fanout_mutex);
1516 if (atomic_dec_and_test(&f->sk_ref)) {
1518 dev_remove_pack(&f->prot_hook);
1521 mutex_unlock(&fanout_mutex);
1524 static const struct proto_ops packet_ops;
1526 static const struct proto_ops packet_ops_spkt;
1528 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1529 struct packet_type *pt, struct net_device *orig_dev)
1532 struct sockaddr_pkt *spkt;
1535 * When we registered the protocol we saved the socket in the data
1536 * field for just this event.
1539 sk = pt->af_packet_priv;
1542 * Yank back the headers [hope the device set this
1543 * right or kerboom...]
1545 * Incoming packets have ll header pulled,
1548 * For outgoing ones skb->data == skb_mac_header(skb)
1549 * so that this procedure is noop.
1552 if (skb->pkt_type == PACKET_LOOPBACK)
1555 if (!net_eq(dev_net(dev), sock_net(sk)))
1558 skb = skb_share_check(skb, GFP_ATOMIC);
1562 /* drop any routing info */
1565 /* drop conntrack reference */
1568 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1570 skb_push(skb, skb->data - skb_mac_header(skb));
1573 * The SOCK_PACKET socket receives _all_ frames.
1576 spkt->spkt_family = dev->type;
1577 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1578 spkt->spkt_protocol = skb->protocol;
1581 * Charge the memory to the socket. This is done specifically
1582 * to prevent sockets using all the memory up.
1585 if (sock_queue_rcv_skb(sk, skb) == 0)
1596 * Output a raw packet to a device layer. This bypasses all the other
1597 * protocol layers and you must therefore supply it with a complete frame
1600 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1601 struct msghdr *msg, size_t len)
1603 struct sock *sk = sock->sk;
1604 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1605 struct sk_buff *skb = NULL;
1606 struct net_device *dev;
1612 * Get and verify the address.
1616 if (msg->msg_namelen < sizeof(struct sockaddr))
1618 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1619 proto = saddr->spkt_protocol;
1621 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1624 * Find the device first to size check it
1627 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1630 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1636 if (!(dev->flags & IFF_UP))
1640 * You may not queue a frame bigger than the mtu. This is the lowest level
1641 * raw protocol and you must do your own fragmentation at this level.
1644 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1645 if (!netif_supports_nofcs(dev)) {
1646 err = -EPROTONOSUPPORT;
1649 extra_len = 4; /* We're doing our own CRC */
1653 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1657 size_t reserved = LL_RESERVED_SPACE(dev);
1658 int tlen = dev->needed_tailroom;
1659 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1662 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1665 /* FIXME: Save some space for broken drivers that write a hard
1666 * header at transmission time by themselves. PPP is the notable
1667 * one here. This should really be fixed at the driver level.
1669 skb_reserve(skb, reserved);
1670 skb_reset_network_header(skb);
1672 /* Try to align data part correctly */
1677 skb_reset_network_header(skb);
1679 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1685 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1686 /* Earlier code assumed this would be a VLAN pkt,
1687 * double-check this now that we have the actual
1690 struct ethhdr *ehdr;
1691 skb_reset_mac_header(skb);
1692 ehdr = eth_hdr(skb);
1693 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1699 skb->protocol = proto;
1701 skb->priority = sk->sk_priority;
1702 skb->mark = sk->sk_mark;
1704 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1706 if (unlikely(extra_len == 4))
1709 skb_probe_transport_header(skb, 0);
1711 dev_queue_xmit(skb);
1722 static unsigned int run_filter(const struct sk_buff *skb,
1723 const struct sock *sk,
1726 struct sk_filter *filter;
1729 filter = rcu_dereference(sk->sk_filter);
1731 res = SK_RUN_FILTER(filter, skb);
1738 * This function makes lazy skb cloning in hope that most of packets
1739 * are discarded by BPF.
1741 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1742 * and skb->cb are mangled. It works because (and until) packets
1743 * falling here are owned by current CPU. Output packets are cloned
1744 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1745 * sequencially, so that if we return skb to original state on exit,
1746 * we will not harm anyone.
1749 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1750 struct packet_type *pt, struct net_device *orig_dev)
1753 struct sockaddr_ll *sll;
1754 struct packet_sock *po;
1755 u8 *skb_head = skb->data;
1756 int skb_len = skb->len;
1757 unsigned int snaplen, res;
1759 if (skb->pkt_type == PACKET_LOOPBACK)
1762 sk = pt->af_packet_priv;
1765 if (!net_eq(dev_net(dev), sock_net(sk)))
1770 if (dev->header_ops) {
1771 /* The device has an explicit notion of ll header,
1772 * exported to higher levels.
1774 * Otherwise, the device hides details of its frame
1775 * structure, so that corresponding packet head is
1776 * never delivered to user.
1778 if (sk->sk_type != SOCK_DGRAM)
1779 skb_push(skb, skb->data - skb_mac_header(skb));
1780 else if (skb->pkt_type == PACKET_OUTGOING) {
1781 /* Special case: outgoing packets have ll header at head */
1782 skb_pull(skb, skb_network_offset(skb));
1788 res = run_filter(skb, sk, snaplen);
1790 goto drop_n_restore;
1794 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1797 if (skb_shared(skb)) {
1798 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1802 if (skb_head != skb->data) {
1803 skb->data = skb_head;
1810 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1813 sll = &PACKET_SKB_CB(skb)->sa.ll;
1814 sll->sll_family = AF_PACKET;
1815 sll->sll_hatype = dev->type;
1816 sll->sll_protocol = skb->protocol;
1817 sll->sll_pkttype = skb->pkt_type;
1818 if (unlikely(po->origdev))
1819 sll->sll_ifindex = orig_dev->ifindex;
1821 sll->sll_ifindex = dev->ifindex;
1823 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1825 PACKET_SKB_CB(skb)->origlen = skb->len;
1827 if (pskb_trim(skb, snaplen))
1830 skb_set_owner_r(skb, sk);
1834 /* drop conntrack reference */
1837 spin_lock(&sk->sk_receive_queue.lock);
1838 po->stats.stats1.tp_packets++;
1839 skb->dropcount = atomic_read(&sk->sk_drops);
1840 __skb_queue_tail(&sk->sk_receive_queue, skb);
1841 spin_unlock(&sk->sk_receive_queue.lock);
1842 sk->sk_data_ready(sk);
1846 spin_lock(&sk->sk_receive_queue.lock);
1847 po->stats.stats1.tp_drops++;
1848 atomic_inc(&sk->sk_drops);
1849 spin_unlock(&sk->sk_receive_queue.lock);
1852 if (skb_head != skb->data && skb_shared(skb)) {
1853 skb->data = skb_head;
1861 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1862 struct packet_type *pt, struct net_device *orig_dev)
1865 struct packet_sock *po;
1866 struct sockaddr_ll *sll;
1867 union tpacket_uhdr h;
1868 u8 *skb_head = skb->data;
1869 int skb_len = skb->len;
1870 unsigned int snaplen, res;
1871 unsigned long status = TP_STATUS_USER;
1872 unsigned short macoff, netoff, hdrlen;
1873 struct sk_buff *copy_skb = NULL;
1877 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
1878 * We may add members to them until current aligned size without forcing
1879 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
1881 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
1882 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
1884 if (skb->pkt_type == PACKET_LOOPBACK)
1887 sk = pt->af_packet_priv;
1890 if (!net_eq(dev_net(dev), sock_net(sk)))
1893 if (dev->header_ops) {
1894 if (sk->sk_type != SOCK_DGRAM)
1895 skb_push(skb, skb->data - skb_mac_header(skb));
1896 else if (skb->pkt_type == PACKET_OUTGOING) {
1897 /* Special case: outgoing packets have ll header at head */
1898 skb_pull(skb, skb_network_offset(skb));
1902 if (skb->ip_summed == CHECKSUM_PARTIAL)
1903 status |= TP_STATUS_CSUMNOTREADY;
1907 res = run_filter(skb, sk, snaplen);
1909 goto drop_n_restore;
1913 if (sk->sk_type == SOCK_DGRAM) {
1914 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1917 unsigned int maclen = skb_network_offset(skb);
1918 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1919 (maclen < 16 ? 16 : maclen)) +
1921 macoff = netoff - maclen;
1923 if (po->tp_version <= TPACKET_V2) {
1924 if (macoff + snaplen > po->rx_ring.frame_size) {
1925 if (po->copy_thresh &&
1926 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1927 if (skb_shared(skb)) {
1928 copy_skb = skb_clone(skb, GFP_ATOMIC);
1930 copy_skb = skb_get(skb);
1931 skb_head = skb->data;
1934 skb_set_owner_r(copy_skb, sk);
1936 snaplen = po->rx_ring.frame_size - macoff;
1937 if ((int)snaplen < 0)
1940 } else if (unlikely(macoff + snaplen >
1941 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
1944 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
1945 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
1946 snaplen, nval, macoff);
1948 if (unlikely((int)snaplen < 0)) {
1950 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
1953 spin_lock(&sk->sk_receive_queue.lock);
1954 h.raw = packet_current_rx_frame(po, skb,
1955 TP_STATUS_KERNEL, (macoff+snaplen));
1958 if (po->tp_version <= TPACKET_V2) {
1959 packet_increment_rx_head(po, &po->rx_ring);
1961 * LOSING will be reported till you read the stats,
1962 * because it's COR - Clear On Read.
1963 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1966 if (po->stats.stats1.tp_drops)
1967 status |= TP_STATUS_LOSING;
1969 po->stats.stats1.tp_packets++;
1971 status |= TP_STATUS_COPY;
1972 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1974 spin_unlock(&sk->sk_receive_queue.lock);
1976 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1978 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1979 getnstimeofday(&ts);
1981 status |= ts_status;
1983 switch (po->tp_version) {
1985 h.h1->tp_len = skb->len;
1986 h.h1->tp_snaplen = snaplen;
1987 h.h1->tp_mac = macoff;
1988 h.h1->tp_net = netoff;
1989 h.h1->tp_sec = ts.tv_sec;
1990 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
1991 hdrlen = sizeof(*h.h1);
1994 h.h2->tp_len = skb->len;
1995 h.h2->tp_snaplen = snaplen;
1996 h.h2->tp_mac = macoff;
1997 h.h2->tp_net = netoff;
1998 h.h2->tp_sec = ts.tv_sec;
1999 h.h2->tp_nsec = ts.tv_nsec;
2000 if (vlan_tx_tag_present(skb)) {
2001 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
2002 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2003 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2005 h.h2->tp_vlan_tci = 0;
2006 h.h2->tp_vlan_tpid = 0;
2008 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2009 hdrlen = sizeof(*h.h2);
2012 /* tp_nxt_offset,vlan are already populated above.
2013 * So DONT clear those fields here
2015 h.h3->tp_status |= status;
2016 h.h3->tp_len = skb->len;
2017 h.h3->tp_snaplen = snaplen;
2018 h.h3->tp_mac = macoff;
2019 h.h3->tp_net = netoff;
2020 h.h3->tp_sec = ts.tv_sec;
2021 h.h3->tp_nsec = ts.tv_nsec;
2022 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2023 hdrlen = sizeof(*h.h3);
2029 sll = h.raw + TPACKET_ALIGN(hdrlen);
2030 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2031 sll->sll_family = AF_PACKET;
2032 sll->sll_hatype = dev->type;
2033 sll->sll_protocol = skb->protocol;
2034 sll->sll_pkttype = skb->pkt_type;
2035 if (unlikely(po->origdev))
2036 sll->sll_ifindex = orig_dev->ifindex;
2038 sll->sll_ifindex = dev->ifindex;
2042 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2043 if (po->tp_version <= TPACKET_V2) {
2046 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2049 for (start = h.raw; start < end; start += PAGE_SIZE)
2050 flush_dcache_page(pgv_to_page(start));
2055 if (po->tp_version <= TPACKET_V2)
2056 __packet_set_status(po, h.raw, status);
2058 prb_clear_blk_fill_status(&po->rx_ring);
2060 sk->sk_data_ready(sk);
2063 if (skb_head != skb->data && skb_shared(skb)) {
2064 skb->data = skb_head;
2072 po->stats.stats1.tp_drops++;
2073 spin_unlock(&sk->sk_receive_queue.lock);
2075 sk->sk_data_ready(sk);
2076 kfree_skb(copy_skb);
2077 goto drop_n_restore;
2080 static void tpacket_destruct_skb(struct sk_buff *skb)
2082 struct packet_sock *po = pkt_sk(skb->sk);
2084 if (likely(po->tx_ring.pg_vec)) {
2088 ph = skb_shinfo(skb)->destructor_arg;
2089 packet_dec_pending(&po->tx_ring);
2091 ts = __packet_set_timestamp(po, ph, skb);
2092 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2098 static bool ll_header_truncated(const struct net_device *dev, int len)
2100 /* net device doesn't like empty head */
2101 if (unlikely(len <= dev->hard_header_len)) {
2102 net_warn_ratelimited("%s: packet size is too short (%d < %d)\n",
2103 current->comm, len, dev->hard_header_len);
2110 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2111 void *frame, struct net_device *dev, int size_max,
2112 __be16 proto, unsigned char *addr, int hlen)
2114 union tpacket_uhdr ph;
2115 int to_write, offset, len, tp_len, nr_frags, len_max;
2116 struct socket *sock = po->sk.sk_socket;
2123 skb->protocol = proto;
2125 skb->priority = po->sk.sk_priority;
2126 skb->mark = po->sk.sk_mark;
2127 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2128 skb_shinfo(skb)->destructor_arg = ph.raw;
2130 switch (po->tp_version) {
2132 tp_len = ph.h2->tp_len;
2135 tp_len = ph.h1->tp_len;
2138 if (unlikely(tp_len > size_max)) {
2139 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2143 skb_reserve(skb, hlen);
2144 skb_reset_network_header(skb);
2146 if (!packet_use_direct_xmit(po))
2147 skb_probe_transport_header(skb, 0);
2148 if (unlikely(po->tp_tx_has_off)) {
2149 int off_min, off_max, off;
2150 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2151 off_max = po->tx_ring.frame_size - tp_len;
2152 if (sock->type == SOCK_DGRAM) {
2153 switch (po->tp_version) {
2155 off = ph.h2->tp_net;
2158 off = ph.h1->tp_net;
2162 switch (po->tp_version) {
2164 off = ph.h2->tp_mac;
2167 off = ph.h1->tp_mac;
2171 if (unlikely((off < off_min) || (off_max < off)))
2173 data = ph.raw + off;
2175 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2179 if (sock->type == SOCK_DGRAM) {
2180 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2182 if (unlikely(err < 0))
2184 } else if (dev->hard_header_len) {
2185 if (ll_header_truncated(dev, tp_len))
2188 skb_push(skb, dev->hard_header_len);
2189 err = skb_store_bits(skb, 0, data,
2190 dev->hard_header_len);
2194 data += dev->hard_header_len;
2195 to_write -= dev->hard_header_len;
2198 offset = offset_in_page(data);
2199 len_max = PAGE_SIZE - offset;
2200 len = ((to_write > len_max) ? len_max : to_write);
2202 skb->data_len = to_write;
2203 skb->len += to_write;
2204 skb->truesize += to_write;
2205 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2207 while (likely(to_write)) {
2208 nr_frags = skb_shinfo(skb)->nr_frags;
2210 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2211 pr_err("Packet exceed the number of skb frags(%lu)\n",
2216 page = pgv_to_page(data);
2218 flush_dcache_page(page);
2220 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2223 len_max = PAGE_SIZE;
2224 len = ((to_write > len_max) ? len_max : to_write);
2230 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2232 struct sk_buff *skb;
2233 struct net_device *dev;
2235 int err, reserve = 0;
2237 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2238 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2239 int tp_len, size_max;
2240 unsigned char *addr;
2242 int status = TP_STATUS_AVAILABLE;
2245 mutex_lock(&po->pg_vec_lock);
2247 if (likely(saddr == NULL)) {
2248 dev = packet_cached_dev_get(po);
2253 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2255 if (msg->msg_namelen < (saddr->sll_halen
2256 + offsetof(struct sockaddr_ll,
2259 proto = saddr->sll_protocol;
2260 addr = saddr->sll_addr;
2261 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2265 if (unlikely(dev == NULL))
2268 if (unlikely(!(dev->flags & IFF_UP)))
2271 reserve = dev->hard_header_len + VLAN_HLEN;
2272 size_max = po->tx_ring.frame_size
2273 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2275 if (size_max > dev->mtu + reserve)
2276 size_max = dev->mtu + reserve;
2279 ph = packet_current_frame(po, &po->tx_ring,
2280 TP_STATUS_SEND_REQUEST);
2281 if (unlikely(ph == NULL)) {
2282 if (need_wait && need_resched())
2287 status = TP_STATUS_SEND_REQUEST;
2288 hlen = LL_RESERVED_SPACE(dev);
2289 tlen = dev->needed_tailroom;
2290 skb = sock_alloc_send_skb(&po->sk,
2291 hlen + tlen + sizeof(struct sockaddr_ll),
2294 if (unlikely(skb == NULL))
2297 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2299 if (tp_len > dev->mtu + dev->hard_header_len) {
2300 struct ethhdr *ehdr;
2301 /* Earlier code assumed this would be a VLAN pkt,
2302 * double-check this now that we have the actual
2306 skb_reset_mac_header(skb);
2307 ehdr = eth_hdr(skb);
2308 if (ehdr->h_proto != htons(ETH_P_8021Q))
2311 if (unlikely(tp_len < 0)) {
2313 __packet_set_status(po, ph,
2314 TP_STATUS_AVAILABLE);
2315 packet_increment_head(&po->tx_ring);
2319 status = TP_STATUS_WRONG_FORMAT;
2325 packet_pick_tx_queue(dev, skb);
2327 skb->destructor = tpacket_destruct_skb;
2328 __packet_set_status(po, ph, TP_STATUS_SENDING);
2329 packet_inc_pending(&po->tx_ring);
2331 status = TP_STATUS_SEND_REQUEST;
2332 err = po->xmit(skb);
2333 if (unlikely(err > 0)) {
2334 err = net_xmit_errno(err);
2335 if (err && __packet_get_status(po, ph) ==
2336 TP_STATUS_AVAILABLE) {
2337 /* skb was destructed already */
2342 * skb was dropped but not destructed yet;
2343 * let's treat it like congestion or err < 0
2347 packet_increment_head(&po->tx_ring);
2349 } while (likely((ph != NULL) ||
2350 /* Note: packet_read_pending() might be slow if we have
2351 * to call it as it's per_cpu variable, but in fast-path
2352 * we already short-circuit the loop with the first
2353 * condition, and luckily don't have to go that path
2356 (need_wait && packet_read_pending(&po->tx_ring))));
2362 __packet_set_status(po, ph, status);
2367 mutex_unlock(&po->pg_vec_lock);
2371 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2372 size_t reserve, size_t len,
2373 size_t linear, int noblock,
2376 struct sk_buff *skb;
2378 /* Under a page? Don't bother with paged skb. */
2379 if (prepad + len < PAGE_SIZE || !linear)
2382 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2387 skb_reserve(skb, reserve);
2388 skb_put(skb, linear);
2389 skb->data_len = len - linear;
2390 skb->len += len - linear;
2395 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2397 struct sock *sk = sock->sk;
2398 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2399 struct sk_buff *skb;
2400 struct net_device *dev;
2402 unsigned char *addr;
2403 int err, reserve = 0;
2404 struct virtio_net_hdr vnet_hdr = { 0 };
2407 struct packet_sock *po = pkt_sk(sk);
2408 unsigned short gso_type = 0;
2414 * Get and verify the address.
2417 if (likely(saddr == NULL)) {
2418 dev = packet_cached_dev_get(po);
2423 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2425 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2427 proto = saddr->sll_protocol;
2428 addr = saddr->sll_addr;
2429 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2433 if (unlikely(dev == NULL))
2436 if (unlikely(!(dev->flags & IFF_UP)))
2439 if (sock->type == SOCK_RAW)
2440 reserve = dev->hard_header_len;
2441 if (po->has_vnet_hdr) {
2442 vnet_hdr_len = sizeof(vnet_hdr);
2445 if (len < vnet_hdr_len)
2448 len -= vnet_hdr_len;
2451 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter);
2452 if (n != vnet_hdr_len)
2455 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2456 (__virtio16_to_cpu(false, vnet_hdr.csum_start) +
2457 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 >
2458 __virtio16_to_cpu(false, vnet_hdr.hdr_len)))
2459 vnet_hdr.hdr_len = __cpu_to_virtio16(false,
2460 __virtio16_to_cpu(false, vnet_hdr.csum_start) +
2461 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2);
2464 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len)
2467 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2468 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2469 case VIRTIO_NET_HDR_GSO_TCPV4:
2470 gso_type = SKB_GSO_TCPV4;
2472 case VIRTIO_NET_HDR_GSO_TCPV6:
2473 gso_type = SKB_GSO_TCPV6;
2475 case VIRTIO_NET_HDR_GSO_UDP:
2476 gso_type = SKB_GSO_UDP;
2482 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2483 gso_type |= SKB_GSO_TCP_ECN;
2485 if (vnet_hdr.gso_size == 0)
2491 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2492 if (!netif_supports_nofcs(dev)) {
2493 err = -EPROTONOSUPPORT;
2496 extra_len = 4; /* We're doing our own CRC */
2500 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2504 hlen = LL_RESERVED_SPACE(dev);
2505 tlen = dev->needed_tailroom;
2506 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2507 __virtio16_to_cpu(false, vnet_hdr.hdr_len),
2508 msg->msg_flags & MSG_DONTWAIT, &err);
2512 skb_set_network_header(skb, reserve);
2515 if (sock->type == SOCK_DGRAM) {
2516 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2517 if (unlikely(offset) < 0)
2520 if (ll_header_truncated(dev, len))
2524 /* Returns -EFAULT on error */
2525 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2529 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2531 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2532 /* Earlier code assumed this would be a VLAN pkt,
2533 * double-check this now that we have the actual
2536 struct ethhdr *ehdr;
2537 skb_reset_mac_header(skb);
2538 ehdr = eth_hdr(skb);
2539 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2545 skb->protocol = proto;
2547 skb->priority = sk->sk_priority;
2548 skb->mark = sk->sk_mark;
2550 packet_pick_tx_queue(dev, skb);
2552 if (po->has_vnet_hdr) {
2553 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2554 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start);
2555 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset);
2556 if (!skb_partial_csum_set(skb, s, o)) {
2562 skb_shinfo(skb)->gso_size =
2563 __virtio16_to_cpu(false, vnet_hdr.gso_size);
2564 skb_shinfo(skb)->gso_type = gso_type;
2566 /* Header must be checked, and gso_segs computed. */
2567 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2568 skb_shinfo(skb)->gso_segs = 0;
2570 len += vnet_hdr_len;
2573 if (!packet_use_direct_xmit(po))
2574 skb_probe_transport_header(skb, reserve);
2575 if (unlikely(extra_len == 4))
2578 err = po->xmit(skb);
2579 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2595 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2596 struct msghdr *msg, size_t len)
2598 struct sock *sk = sock->sk;
2599 struct packet_sock *po = pkt_sk(sk);
2601 if (po->tx_ring.pg_vec)
2602 return tpacket_snd(po, msg);
2604 return packet_snd(sock, msg, len);
2608 * Close a PACKET socket. This is fairly simple. We immediately go
2609 * to 'closed' state and remove our protocol entry in the device list.
2612 static int packet_release(struct socket *sock)
2614 struct sock *sk = sock->sk;
2615 struct packet_sock *po;
2617 union tpacket_req_u req_u;
2625 mutex_lock(&net->packet.sklist_lock);
2626 sk_del_node_init_rcu(sk);
2627 mutex_unlock(&net->packet.sklist_lock);
2630 sock_prot_inuse_add(net, sk->sk_prot, -1);
2633 spin_lock(&po->bind_lock);
2634 unregister_prot_hook(sk, false);
2635 packet_cached_dev_reset(po);
2637 if (po->prot_hook.dev) {
2638 dev_put(po->prot_hook.dev);
2639 po->prot_hook.dev = NULL;
2641 spin_unlock(&po->bind_lock);
2643 packet_flush_mclist(sk);
2645 if (po->rx_ring.pg_vec) {
2646 memset(&req_u, 0, sizeof(req_u));
2647 packet_set_ring(sk, &req_u, 1, 0);
2650 if (po->tx_ring.pg_vec) {
2651 memset(&req_u, 0, sizeof(req_u));
2652 packet_set_ring(sk, &req_u, 1, 1);
2659 * Now the socket is dead. No more input will appear.
2666 skb_queue_purge(&sk->sk_receive_queue);
2667 packet_free_pending(po);
2668 sk_refcnt_debug_release(sk);
2675 * Attach a packet hook.
2678 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2680 struct packet_sock *po = pkt_sk(sk);
2681 const struct net_device *dev_curr;
2693 spin_lock(&po->bind_lock);
2695 proto_curr = po->prot_hook.type;
2696 dev_curr = po->prot_hook.dev;
2698 need_rehook = proto_curr != proto || dev_curr != dev;
2701 unregister_prot_hook(sk, true);
2704 po->prot_hook.type = proto;
2706 if (po->prot_hook.dev)
2707 dev_put(po->prot_hook.dev);
2709 po->prot_hook.dev = dev;
2711 po->ifindex = dev ? dev->ifindex : 0;
2712 packet_cached_dev_assign(po, dev);
2715 if (proto == 0 || !need_rehook)
2718 if (!dev || (dev->flags & IFF_UP)) {
2719 register_prot_hook(sk);
2721 sk->sk_err = ENETDOWN;
2722 if (!sock_flag(sk, SOCK_DEAD))
2723 sk->sk_error_report(sk);
2727 spin_unlock(&po->bind_lock);
2733 * Bind a packet socket to a device
2736 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2739 struct sock *sk = sock->sk;
2741 struct net_device *dev;
2748 if (addr_len != sizeof(struct sockaddr))
2750 strlcpy(name, uaddr->sa_data, sizeof(name));
2752 dev = dev_get_by_name(sock_net(sk), name);
2754 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2758 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2760 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2761 struct sock *sk = sock->sk;
2762 struct net_device *dev = NULL;
2770 if (addr_len < sizeof(struct sockaddr_ll))
2772 if (sll->sll_family != AF_PACKET)
2775 if (sll->sll_ifindex) {
2777 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2781 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2787 static struct proto packet_proto = {
2789 .owner = THIS_MODULE,
2790 .obj_size = sizeof(struct packet_sock),
2794 * Create a packet of type SOCK_PACKET.
2797 static int packet_create(struct net *net, struct socket *sock, int protocol,
2801 struct packet_sock *po;
2802 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2805 if (!ns_capable(net->user_ns, CAP_NET_RAW))
2807 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2808 sock->type != SOCK_PACKET)
2809 return -ESOCKTNOSUPPORT;
2811 sock->state = SS_UNCONNECTED;
2814 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2818 sock->ops = &packet_ops;
2819 if (sock->type == SOCK_PACKET)
2820 sock->ops = &packet_ops_spkt;
2822 sock_init_data(sock, sk);
2825 sk->sk_family = PF_PACKET;
2827 po->xmit = dev_queue_xmit;
2829 err = packet_alloc_pending(po);
2833 packet_cached_dev_reset(po);
2835 sk->sk_destruct = packet_sock_destruct;
2836 sk_refcnt_debug_inc(sk);
2839 * Attach a protocol block
2842 spin_lock_init(&po->bind_lock);
2843 mutex_init(&po->pg_vec_lock);
2844 po->prot_hook.func = packet_rcv;
2846 if (sock->type == SOCK_PACKET)
2847 po->prot_hook.func = packet_rcv_spkt;
2849 po->prot_hook.af_packet_priv = sk;
2852 po->prot_hook.type = proto;
2853 register_prot_hook(sk);
2856 mutex_lock(&net->packet.sklist_lock);
2857 sk_add_node_rcu(sk, &net->packet.sklist);
2858 mutex_unlock(&net->packet.sklist_lock);
2861 sock_prot_inuse_add(net, &packet_proto, 1);
2872 * Pull a packet from our receive queue and hand it to the user.
2873 * If necessary we block.
2876 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2877 struct msghdr *msg, size_t len, int flags)
2879 struct sock *sk = sock->sk;
2880 struct sk_buff *skb;
2882 int vnet_hdr_len = 0;
2885 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2889 /* What error should we return now? EUNATTACH? */
2890 if (pkt_sk(sk)->ifindex < 0)
2894 if (flags & MSG_ERRQUEUE) {
2895 err = sock_recv_errqueue(sk, msg, len,
2896 SOL_PACKET, PACKET_TX_TIMESTAMP);
2901 * Call the generic datagram receiver. This handles all sorts
2902 * of horrible races and re-entrancy so we can forget about it
2903 * in the protocol layers.
2905 * Now it will return ENETDOWN, if device have just gone down,
2906 * but then it will block.
2909 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2912 * An error occurred so return it. Because skb_recv_datagram()
2913 * handles the blocking we don't see and worry about blocking
2920 if (pkt_sk(sk)->has_vnet_hdr) {
2921 struct virtio_net_hdr vnet_hdr = { 0 };
2924 vnet_hdr_len = sizeof(vnet_hdr);
2925 if (len < vnet_hdr_len)
2928 len -= vnet_hdr_len;
2930 if (skb_is_gso(skb)) {
2931 struct skb_shared_info *sinfo = skb_shinfo(skb);
2933 /* This is a hint as to how much should be linear. */
2935 __cpu_to_virtio16(false, skb_headlen(skb));
2937 __cpu_to_virtio16(false, sinfo->gso_size);
2938 if (sinfo->gso_type & SKB_GSO_TCPV4)
2939 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2940 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2941 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2942 else if (sinfo->gso_type & SKB_GSO_UDP)
2943 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2944 else if (sinfo->gso_type & SKB_GSO_FCOE)
2948 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2949 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2951 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2953 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2954 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2955 vnet_hdr.csum_start = __cpu_to_virtio16(false,
2956 skb_checksum_start_offset(skb));
2957 vnet_hdr.csum_offset = __cpu_to_virtio16(false,
2959 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2960 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2961 } /* else everything is zero */
2963 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
2968 /* You lose any data beyond the buffer you gave. If it worries
2969 * a user program they can ask the device for its MTU
2975 msg->msg_flags |= MSG_TRUNC;
2978 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2982 sock_recv_ts_and_drops(msg, sk, skb);
2984 if (msg->msg_name) {
2985 /* If the address length field is there to be filled
2986 * in, we fill it in now.
2988 if (sock->type == SOCK_PACKET) {
2989 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
2990 msg->msg_namelen = sizeof(struct sockaddr_pkt);
2992 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2993 msg->msg_namelen = sll->sll_halen +
2994 offsetof(struct sockaddr_ll, sll_addr);
2996 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3000 if (pkt_sk(sk)->auxdata) {
3001 struct tpacket_auxdata aux;
3003 aux.tp_status = TP_STATUS_USER;
3004 if (skb->ip_summed == CHECKSUM_PARTIAL)
3005 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3006 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
3007 aux.tp_snaplen = skb->len;
3009 aux.tp_net = skb_network_offset(skb);
3010 if (vlan_tx_tag_present(skb)) {
3011 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
3012 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3013 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3015 aux.tp_vlan_tci = 0;
3016 aux.tp_vlan_tpid = 0;
3018 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3022 * Free or return the buffer as appropriate. Again this
3023 * hides all the races and re-entrancy issues from us.
3025 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3028 skb_free_datagram(sk, skb);
3033 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3034 int *uaddr_len, int peer)
3036 struct net_device *dev;
3037 struct sock *sk = sock->sk;
3042 uaddr->sa_family = AF_PACKET;
3043 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3045 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3047 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3049 *uaddr_len = sizeof(*uaddr);
3054 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3055 int *uaddr_len, int peer)
3057 struct net_device *dev;
3058 struct sock *sk = sock->sk;
3059 struct packet_sock *po = pkt_sk(sk);
3060 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3065 sll->sll_family = AF_PACKET;
3066 sll->sll_ifindex = po->ifindex;
3067 sll->sll_protocol = po->num;
3068 sll->sll_pkttype = 0;
3070 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3072 sll->sll_hatype = dev->type;
3073 sll->sll_halen = dev->addr_len;
3074 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3076 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3080 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3085 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3089 case PACKET_MR_MULTICAST:
3090 if (i->alen != dev->addr_len)
3093 return dev_mc_add(dev, i->addr);
3095 return dev_mc_del(dev, i->addr);
3097 case PACKET_MR_PROMISC:
3098 return dev_set_promiscuity(dev, what);
3099 case PACKET_MR_ALLMULTI:
3100 return dev_set_allmulti(dev, what);
3101 case PACKET_MR_UNICAST:
3102 if (i->alen != dev->addr_len)
3105 return dev_uc_add(dev, i->addr);
3107 return dev_uc_del(dev, i->addr);
3115 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
3117 for ( ; i; i = i->next) {
3118 if (i->ifindex == dev->ifindex)
3119 packet_dev_mc(dev, i, what);
3123 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3125 struct packet_sock *po = pkt_sk(sk);
3126 struct packet_mclist *ml, *i;
3127 struct net_device *dev;
3133 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3138 if (mreq->mr_alen > dev->addr_len)
3142 i = kmalloc(sizeof(*i), GFP_KERNEL);
3147 for (ml = po->mclist; ml; ml = ml->next) {
3148 if (ml->ifindex == mreq->mr_ifindex &&
3149 ml->type == mreq->mr_type &&
3150 ml->alen == mreq->mr_alen &&
3151 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3153 /* Free the new element ... */
3159 i->type = mreq->mr_type;
3160 i->ifindex = mreq->mr_ifindex;
3161 i->alen = mreq->mr_alen;
3162 memcpy(i->addr, mreq->mr_address, i->alen);
3164 i->next = po->mclist;
3166 err = packet_dev_mc(dev, i, 1);
3168 po->mclist = i->next;
3177 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3179 struct packet_mclist *ml, **mlp;
3183 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3184 if (ml->ifindex == mreq->mr_ifindex &&
3185 ml->type == mreq->mr_type &&
3186 ml->alen == mreq->mr_alen &&
3187 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3188 if (--ml->count == 0) {
3189 struct net_device *dev;
3191 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3193 packet_dev_mc(dev, ml, -1);
3201 return -EADDRNOTAVAIL;
3204 static void packet_flush_mclist(struct sock *sk)
3206 struct packet_sock *po = pkt_sk(sk);
3207 struct packet_mclist *ml;
3213 while ((ml = po->mclist) != NULL) {
3214 struct net_device *dev;
3216 po->mclist = ml->next;
3217 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3219 packet_dev_mc(dev, ml, -1);
3226 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3228 struct sock *sk = sock->sk;
3229 struct packet_sock *po = pkt_sk(sk);
3232 if (level != SOL_PACKET)
3233 return -ENOPROTOOPT;
3236 case PACKET_ADD_MEMBERSHIP:
3237 case PACKET_DROP_MEMBERSHIP:
3239 struct packet_mreq_max mreq;
3241 memset(&mreq, 0, sizeof(mreq));
3242 if (len < sizeof(struct packet_mreq))
3244 if (len > sizeof(mreq))
3246 if (copy_from_user(&mreq, optval, len))
3248 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3250 if (optname == PACKET_ADD_MEMBERSHIP)
3251 ret = packet_mc_add(sk, &mreq);
3253 ret = packet_mc_drop(sk, &mreq);
3257 case PACKET_RX_RING:
3258 case PACKET_TX_RING:
3260 union tpacket_req_u req_u;
3263 switch (po->tp_version) {
3266 len = sizeof(req_u.req);
3270 len = sizeof(req_u.req3);
3275 if (pkt_sk(sk)->has_vnet_hdr)
3277 if (copy_from_user(&req_u.req, optval, len))
3279 return packet_set_ring(sk, &req_u, 0,
3280 optname == PACKET_TX_RING);
3282 case PACKET_COPY_THRESH:
3286 if (optlen != sizeof(val))
3288 if (copy_from_user(&val, optval, sizeof(val)))
3291 pkt_sk(sk)->copy_thresh = val;
3294 case PACKET_VERSION:
3298 if (optlen != sizeof(val))
3300 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3302 if (copy_from_user(&val, optval, sizeof(val)))
3308 po->tp_version = val;
3314 case PACKET_RESERVE:
3318 if (optlen != sizeof(val))
3320 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3322 if (copy_from_user(&val, optval, sizeof(val)))
3324 po->tp_reserve = val;
3331 if (optlen != sizeof(val))
3333 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3335 if (copy_from_user(&val, optval, sizeof(val)))
3337 po->tp_loss = !!val;
3340 case PACKET_AUXDATA:
3344 if (optlen < sizeof(val))
3346 if (copy_from_user(&val, optval, sizeof(val)))
3349 po->auxdata = !!val;
3352 case PACKET_ORIGDEV:
3356 if (optlen < sizeof(val))
3358 if (copy_from_user(&val, optval, sizeof(val)))
3361 po->origdev = !!val;
3364 case PACKET_VNET_HDR:
3368 if (sock->type != SOCK_RAW)
3370 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3372 if (optlen < sizeof(val))
3374 if (copy_from_user(&val, optval, sizeof(val)))
3377 po->has_vnet_hdr = !!val;
3380 case PACKET_TIMESTAMP:
3384 if (optlen != sizeof(val))
3386 if (copy_from_user(&val, optval, sizeof(val)))
3389 po->tp_tstamp = val;
3396 if (optlen != sizeof(val))
3398 if (copy_from_user(&val, optval, sizeof(val)))
3401 return fanout_add(sk, val & 0xffff, val >> 16);
3403 case PACKET_TX_HAS_OFF:
3407 if (optlen != sizeof(val))
3409 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3411 if (copy_from_user(&val, optval, sizeof(val)))
3413 po->tp_tx_has_off = !!val;
3416 case PACKET_QDISC_BYPASS:
3420 if (optlen != sizeof(val))
3422 if (copy_from_user(&val, optval, sizeof(val)))
3425 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3429 return -ENOPROTOOPT;
3433 static int packet_getsockopt(struct socket *sock, int level, int optname,
3434 char __user *optval, int __user *optlen)
3437 int val, lv = sizeof(val);
3438 struct sock *sk = sock->sk;
3439 struct packet_sock *po = pkt_sk(sk);
3441 union tpacket_stats_u st;
3443 if (level != SOL_PACKET)
3444 return -ENOPROTOOPT;
3446 if (get_user(len, optlen))
3453 case PACKET_STATISTICS:
3454 spin_lock_bh(&sk->sk_receive_queue.lock);
3455 memcpy(&st, &po->stats, sizeof(st));
3456 memset(&po->stats, 0, sizeof(po->stats));
3457 spin_unlock_bh(&sk->sk_receive_queue.lock);
3459 if (po->tp_version == TPACKET_V3) {
3460 lv = sizeof(struct tpacket_stats_v3);
3461 st.stats3.tp_packets += st.stats3.tp_drops;
3464 lv = sizeof(struct tpacket_stats);
3465 st.stats1.tp_packets += st.stats1.tp_drops;
3470 case PACKET_AUXDATA:
3473 case PACKET_ORIGDEV:
3476 case PACKET_VNET_HDR:
3477 val = po->has_vnet_hdr;
3479 case PACKET_VERSION:
3480 val = po->tp_version;
3483 if (len > sizeof(int))
3485 if (copy_from_user(&val, optval, len))
3489 val = sizeof(struct tpacket_hdr);
3492 val = sizeof(struct tpacket2_hdr);
3495 val = sizeof(struct tpacket3_hdr);
3501 case PACKET_RESERVE:
3502 val = po->tp_reserve;
3507 case PACKET_TIMESTAMP:
3508 val = po->tp_tstamp;
3512 ((u32)po->fanout->id |
3513 ((u32)po->fanout->type << 16) |
3514 ((u32)po->fanout->flags << 24)) :
3517 case PACKET_TX_HAS_OFF:
3518 val = po->tp_tx_has_off;
3520 case PACKET_QDISC_BYPASS:
3521 val = packet_use_direct_xmit(po);
3524 return -ENOPROTOOPT;
3529 if (put_user(len, optlen))
3531 if (copy_to_user(optval, data, len))
3537 static int packet_notifier(struct notifier_block *this,
3538 unsigned long msg, void *ptr)
3541 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3542 struct net *net = dev_net(dev);
3545 sk_for_each_rcu(sk, &net->packet.sklist) {
3546 struct packet_sock *po = pkt_sk(sk);
3549 case NETDEV_UNREGISTER:
3551 packet_dev_mclist(dev, po->mclist, -1);
3555 if (dev->ifindex == po->ifindex) {
3556 spin_lock(&po->bind_lock);
3558 __unregister_prot_hook(sk, false);
3559 sk->sk_err = ENETDOWN;
3560 if (!sock_flag(sk, SOCK_DEAD))
3561 sk->sk_error_report(sk);
3563 if (msg == NETDEV_UNREGISTER) {
3564 packet_cached_dev_reset(po);
3566 if (po->prot_hook.dev)
3567 dev_put(po->prot_hook.dev);
3568 po->prot_hook.dev = NULL;
3570 spin_unlock(&po->bind_lock);
3574 if (dev->ifindex == po->ifindex) {
3575 spin_lock(&po->bind_lock);
3577 register_prot_hook(sk);
3578 spin_unlock(&po->bind_lock);
3588 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3591 struct sock *sk = sock->sk;
3596 int amount = sk_wmem_alloc_get(sk);
3598 return put_user(amount, (int __user *)arg);
3602 struct sk_buff *skb;
3605 spin_lock_bh(&sk->sk_receive_queue.lock);
3606 skb = skb_peek(&sk->sk_receive_queue);
3609 spin_unlock_bh(&sk->sk_receive_queue.lock);
3610 return put_user(amount, (int __user *)arg);
3613 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3615 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3625 case SIOCGIFBRDADDR:
3626 case SIOCSIFBRDADDR:
3627 case SIOCGIFNETMASK:
3628 case SIOCSIFNETMASK:
3629 case SIOCGIFDSTADDR:
3630 case SIOCSIFDSTADDR:
3632 return inet_dgram_ops.ioctl(sock, cmd, arg);
3636 return -ENOIOCTLCMD;
3641 static unsigned int packet_poll(struct file *file, struct socket *sock,
3644 struct sock *sk = sock->sk;
3645 struct packet_sock *po = pkt_sk(sk);
3646 unsigned int mask = datagram_poll(file, sock, wait);
3648 spin_lock_bh(&sk->sk_receive_queue.lock);
3649 if (po->rx_ring.pg_vec) {
3650 if (!packet_previous_rx_frame(po, &po->rx_ring,
3652 mask |= POLLIN | POLLRDNORM;
3654 spin_unlock_bh(&sk->sk_receive_queue.lock);
3655 spin_lock_bh(&sk->sk_write_queue.lock);
3656 if (po->tx_ring.pg_vec) {
3657 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3658 mask |= POLLOUT | POLLWRNORM;
3660 spin_unlock_bh(&sk->sk_write_queue.lock);
3665 /* Dirty? Well, I still did not learn better way to account
3669 static void packet_mm_open(struct vm_area_struct *vma)
3671 struct file *file = vma->vm_file;
3672 struct socket *sock = file->private_data;
3673 struct sock *sk = sock->sk;
3676 atomic_inc(&pkt_sk(sk)->mapped);
3679 static void packet_mm_close(struct vm_area_struct *vma)
3681 struct file *file = vma->vm_file;
3682 struct socket *sock = file->private_data;
3683 struct sock *sk = sock->sk;
3686 atomic_dec(&pkt_sk(sk)->mapped);
3689 static const struct vm_operations_struct packet_mmap_ops = {
3690 .open = packet_mm_open,
3691 .close = packet_mm_close,
3694 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3699 for (i = 0; i < len; i++) {
3700 if (likely(pg_vec[i].buffer)) {
3701 if (is_vmalloc_addr(pg_vec[i].buffer))
3702 vfree(pg_vec[i].buffer);
3704 free_pages((unsigned long)pg_vec[i].buffer,
3706 pg_vec[i].buffer = NULL;
3712 static char *alloc_one_pg_vec_page(unsigned long order)
3715 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3716 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3718 buffer = (char *) __get_free_pages(gfp_flags, order);
3722 /* __get_free_pages failed, fall back to vmalloc */
3723 buffer = vzalloc((1 << order) * PAGE_SIZE);
3727 /* vmalloc failed, lets dig into swap here */
3728 gfp_flags &= ~__GFP_NORETRY;
3729 buffer = (char *) __get_free_pages(gfp_flags, order);
3733 /* complete and utter failure */
3737 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3739 unsigned int block_nr = req->tp_block_nr;
3743 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3744 if (unlikely(!pg_vec))
3747 for (i = 0; i < block_nr; i++) {
3748 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3749 if (unlikely(!pg_vec[i].buffer))
3750 goto out_free_pgvec;
3757 free_pg_vec(pg_vec, order, block_nr);
3762 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3763 int closing, int tx_ring)
3765 struct pgv *pg_vec = NULL;
3766 struct packet_sock *po = pkt_sk(sk);
3767 int was_running, order = 0;
3768 struct packet_ring_buffer *rb;
3769 struct sk_buff_head *rb_queue;
3772 /* Added to avoid minimal code churn */
3773 struct tpacket_req *req = &req_u->req;
3775 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3776 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3777 WARN(1, "Tx-ring is not supported.\n");
3781 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3782 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3786 if (atomic_read(&po->mapped))
3788 if (packet_read_pending(rb))
3792 if (req->tp_block_nr) {
3793 /* Sanity tests and some calculations */
3795 if (unlikely(rb->pg_vec))
3798 switch (po->tp_version) {
3800 po->tp_hdrlen = TPACKET_HDRLEN;
3803 po->tp_hdrlen = TPACKET2_HDRLEN;
3806 po->tp_hdrlen = TPACKET3_HDRLEN;
3811 if (unlikely((int)req->tp_block_size <= 0))
3813 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3815 if (po->tp_version >= TPACKET_V3 &&
3816 (int)(req->tp_block_size -
3817 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
3819 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3822 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3825 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3826 if (unlikely(rb->frames_per_block <= 0))
3828 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3833 order = get_order(req->tp_block_size);
3834 pg_vec = alloc_pg_vec(req, order);
3835 if (unlikely(!pg_vec))
3837 switch (po->tp_version) {
3839 /* Transmit path is not supported. We checked
3840 * it above but just being paranoid
3843 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3852 if (unlikely(req->tp_frame_nr))
3858 /* Detach socket from network */
3859 spin_lock(&po->bind_lock);
3860 was_running = po->running;
3864 __unregister_prot_hook(sk, false);
3866 spin_unlock(&po->bind_lock);
3871 mutex_lock(&po->pg_vec_lock);
3872 if (closing || atomic_read(&po->mapped) == 0) {
3874 spin_lock_bh(&rb_queue->lock);
3875 swap(rb->pg_vec, pg_vec);
3876 rb->frame_max = (req->tp_frame_nr - 1);
3878 rb->frame_size = req->tp_frame_size;
3879 spin_unlock_bh(&rb_queue->lock);
3881 swap(rb->pg_vec_order, order);
3882 swap(rb->pg_vec_len, req->tp_block_nr);
3884 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3885 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3886 tpacket_rcv : packet_rcv;
3887 skb_queue_purge(rb_queue);
3888 if (atomic_read(&po->mapped))
3889 pr_err("packet_mmap: vma is busy: %d\n",
3890 atomic_read(&po->mapped));
3892 mutex_unlock(&po->pg_vec_lock);
3894 spin_lock(&po->bind_lock);
3897 register_prot_hook(sk);
3899 spin_unlock(&po->bind_lock);
3900 if (closing && (po->tp_version > TPACKET_V2)) {
3901 /* Because we don't support block-based V3 on tx-ring */
3903 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3908 free_pg_vec(pg_vec, order, req->tp_block_nr);
3913 static int packet_mmap(struct file *file, struct socket *sock,
3914 struct vm_area_struct *vma)
3916 struct sock *sk = sock->sk;
3917 struct packet_sock *po = pkt_sk(sk);
3918 unsigned long size, expected_size;
3919 struct packet_ring_buffer *rb;
3920 unsigned long start;
3927 mutex_lock(&po->pg_vec_lock);
3930 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3932 expected_size += rb->pg_vec_len
3938 if (expected_size == 0)
3941 size = vma->vm_end - vma->vm_start;
3942 if (size != expected_size)
3945 start = vma->vm_start;
3946 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3947 if (rb->pg_vec == NULL)
3950 for (i = 0; i < rb->pg_vec_len; i++) {
3952 void *kaddr = rb->pg_vec[i].buffer;
3955 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3956 page = pgv_to_page(kaddr);
3957 err = vm_insert_page(vma, start, page);
3966 atomic_inc(&po->mapped);
3967 vma->vm_ops = &packet_mmap_ops;
3971 mutex_unlock(&po->pg_vec_lock);
3975 static const struct proto_ops packet_ops_spkt = {
3976 .family = PF_PACKET,
3977 .owner = THIS_MODULE,
3978 .release = packet_release,
3979 .bind = packet_bind_spkt,
3980 .connect = sock_no_connect,
3981 .socketpair = sock_no_socketpair,
3982 .accept = sock_no_accept,
3983 .getname = packet_getname_spkt,
3984 .poll = datagram_poll,
3985 .ioctl = packet_ioctl,
3986 .listen = sock_no_listen,
3987 .shutdown = sock_no_shutdown,
3988 .setsockopt = sock_no_setsockopt,
3989 .getsockopt = sock_no_getsockopt,
3990 .sendmsg = packet_sendmsg_spkt,
3991 .recvmsg = packet_recvmsg,
3992 .mmap = sock_no_mmap,
3993 .sendpage = sock_no_sendpage,
3996 static const struct proto_ops packet_ops = {
3997 .family = PF_PACKET,
3998 .owner = THIS_MODULE,
3999 .release = packet_release,
4000 .bind = packet_bind,
4001 .connect = sock_no_connect,
4002 .socketpair = sock_no_socketpair,
4003 .accept = sock_no_accept,
4004 .getname = packet_getname,
4005 .poll = packet_poll,
4006 .ioctl = packet_ioctl,
4007 .listen = sock_no_listen,
4008 .shutdown = sock_no_shutdown,
4009 .setsockopt = packet_setsockopt,
4010 .getsockopt = packet_getsockopt,
4011 .sendmsg = packet_sendmsg,
4012 .recvmsg = packet_recvmsg,
4013 .mmap = packet_mmap,
4014 .sendpage = sock_no_sendpage,
4017 static const struct net_proto_family packet_family_ops = {
4018 .family = PF_PACKET,
4019 .create = packet_create,
4020 .owner = THIS_MODULE,
4023 static struct notifier_block packet_netdev_notifier = {
4024 .notifier_call = packet_notifier,
4027 #ifdef CONFIG_PROC_FS
4029 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4032 struct net *net = seq_file_net(seq);
4035 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4038 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4040 struct net *net = seq_file_net(seq);
4041 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4044 static void packet_seq_stop(struct seq_file *seq, void *v)
4050 static int packet_seq_show(struct seq_file *seq, void *v)
4052 if (v == SEQ_START_TOKEN)
4053 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4055 struct sock *s = sk_entry(v);
4056 const struct packet_sock *po = pkt_sk(s);
4059 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4061 atomic_read(&s->sk_refcnt),
4066 atomic_read(&s->sk_rmem_alloc),
4067 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4074 static const struct seq_operations packet_seq_ops = {
4075 .start = packet_seq_start,
4076 .next = packet_seq_next,
4077 .stop = packet_seq_stop,
4078 .show = packet_seq_show,
4081 static int packet_seq_open(struct inode *inode, struct file *file)
4083 return seq_open_net(inode, file, &packet_seq_ops,
4084 sizeof(struct seq_net_private));
4087 static const struct file_operations packet_seq_fops = {
4088 .owner = THIS_MODULE,
4089 .open = packet_seq_open,
4091 .llseek = seq_lseek,
4092 .release = seq_release_net,
4097 static int __net_init packet_net_init(struct net *net)
4099 mutex_init(&net->packet.sklist_lock);
4100 INIT_HLIST_HEAD(&net->packet.sklist);
4102 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4108 static void __net_exit packet_net_exit(struct net *net)
4110 remove_proc_entry("packet", net->proc_net);
4113 static struct pernet_operations packet_net_ops = {
4114 .init = packet_net_init,
4115 .exit = packet_net_exit,
4119 static void __exit packet_exit(void)
4121 unregister_netdevice_notifier(&packet_netdev_notifier);
4122 unregister_pernet_subsys(&packet_net_ops);
4123 sock_unregister(PF_PACKET);
4124 proto_unregister(&packet_proto);
4127 static int __init packet_init(void)
4129 int rc = proto_register(&packet_proto, 0);
4134 sock_register(&packet_family_ops);
4135 register_pernet_subsys(&packet_net_ops);
4136 register_netdevice_notifier(&packet_netdev_notifier);
4141 module_init(packet_init);
4142 module_exit(packet_exit);
4143 MODULE_LICENSE("GPL");
4144 MODULE_ALIAS_NETPROTO(PF_PACKET);