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/delay.h>
67 #include <linux/kmod.h>
68 #include <linux/slab.h>
69 #include <linux/vmalloc.h>
70 #include <net/net_namespace.h>
72 #include <net/protocol.h>
73 #include <linux/skbuff.h>
75 #include <linux/errno.h>
76 #include <linux/timer.h>
77 #include <asm/uaccess.h>
78 #include <asm/ioctls.h>
80 #include <asm/cacheflush.h>
82 #include <linux/proc_fs.h>
83 #include <linux/seq_file.h>
84 #include <linux/poll.h>
85 #include <linux/module.h>
86 #include <linux/init.h>
87 #include <linux/mutex.h>
88 #include <linux/if_vlan.h>
89 #include <linux/virtio_net.h>
90 #include <linux/errqueue.h>
91 #include <linux/net_tstamp.h>
92 #include <linux/percpu.h>
94 #include <net/inet_common.h>
101 - if device has no dev->hard_header routine, it adds and removes ll header
102 inside itself. In this case ll header is invisible outside of device,
103 but higher levels still should reserve dev->hard_header_len.
104 Some devices are enough clever to reallocate skb, when header
105 will not fit to reserved space (tunnel), another ones are silly
107 - packet socket receives packets with pulled ll header,
108 so that SOCK_RAW should push it back.
113 Incoming, dev->hard_header!=NULL
114 mac_header -> ll header
117 Outgoing, dev->hard_header!=NULL
118 mac_header -> ll header
121 Incoming, dev->hard_header==NULL
122 mac_header -> UNKNOWN position. It is very likely, that it points to ll
123 header. PPP makes it, that is wrong, because introduce
124 assymetry between rx and tx paths.
127 Outgoing, dev->hard_header==NULL
128 mac_header -> data. ll header is still not built!
132 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
138 dev->hard_header != NULL
139 mac_header -> ll header
142 dev->hard_header == NULL (ll header is added by device, we cannot control it)
146 We should set nh.raw on output to correct posistion,
147 packet classifier depends on it.
150 /* Private packet socket structures. */
152 /* identical to struct packet_mreq except it has
153 * a longer address field.
155 struct packet_mreq_max {
157 unsigned short mr_type;
158 unsigned short mr_alen;
159 unsigned char mr_address[MAX_ADDR_LEN];
163 struct tpacket_hdr *h1;
164 struct tpacket2_hdr *h2;
165 struct tpacket3_hdr *h3;
169 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
170 int closing, int tx_ring);
172 #define V3_ALIGNMENT (8)
174 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
176 #define BLK_PLUS_PRIV(sz_of_priv) \
177 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
179 #define PGV_FROM_VMALLOC 1
181 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
182 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
183 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
184 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
185 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
186 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
187 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
190 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
191 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
192 struct packet_type *pt, struct net_device *orig_dev);
194 static void *packet_previous_frame(struct packet_sock *po,
195 struct packet_ring_buffer *rb,
197 static void packet_increment_head(struct packet_ring_buffer *buff);
198 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
199 struct tpacket_block_desc *);
200 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
201 struct packet_sock *);
202 static void prb_retire_current_block(struct tpacket_kbdq_core *,
203 struct packet_sock *, unsigned int status);
204 static int prb_queue_frozen(struct tpacket_kbdq_core *);
205 static void prb_open_block(struct tpacket_kbdq_core *,
206 struct tpacket_block_desc *);
207 static void prb_retire_rx_blk_timer_expired(unsigned long);
208 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
209 static void prb_init_blk_timer(struct packet_sock *,
210 struct tpacket_kbdq_core *,
211 void (*func) (unsigned long));
212 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
213 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
214 struct tpacket3_hdr *);
215 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
216 struct tpacket3_hdr *);
217 static void packet_flush_mclist(struct sock *sk);
219 struct packet_skb_cb {
221 struct sockaddr_pkt pkt;
223 /* Trick: alias skb original length with
224 * ll.sll_family and ll.protocol in order
227 unsigned int origlen;
228 struct sockaddr_ll ll;
233 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
235 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
236 #define GET_PBLOCK_DESC(x, bid) \
237 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
238 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
239 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
240 #define GET_NEXT_PRB_BLK_NUM(x) \
241 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
242 ((x)->kactive_blk_num+1) : 0)
244 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
245 static void __fanout_link(struct sock *sk, struct packet_sock *po);
247 static int packet_direct_xmit(struct sk_buff *skb)
249 struct net_device *dev = skb->dev;
250 netdev_features_t features;
251 struct netdev_queue *txq;
252 int ret = NETDEV_TX_BUSY;
254 if (unlikely(!netif_running(dev) ||
255 !netif_carrier_ok(dev)))
258 features = netif_skb_features(skb);
259 if (skb_needs_linearize(skb, features) &&
260 __skb_linearize(skb))
263 txq = skb_get_tx_queue(dev, skb);
267 HARD_TX_LOCK(dev, txq, smp_processor_id());
268 if (!netif_xmit_frozen_or_drv_stopped(txq))
269 ret = netdev_start_xmit(skb, dev, txq, false);
270 HARD_TX_UNLOCK(dev, txq);
274 if (!dev_xmit_complete(ret))
279 atomic_long_inc(&dev->tx_dropped);
281 return NET_XMIT_DROP;
284 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
286 struct net_device *dev;
289 dev = rcu_dereference(po->cached_dev);
297 static void packet_cached_dev_assign(struct packet_sock *po,
298 struct net_device *dev)
300 rcu_assign_pointer(po->cached_dev, dev);
303 static void packet_cached_dev_reset(struct packet_sock *po)
305 RCU_INIT_POINTER(po->cached_dev, NULL);
308 static bool packet_use_direct_xmit(const struct packet_sock *po)
310 return po->xmit == packet_direct_xmit;
313 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
315 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
318 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
320 const struct net_device_ops *ops = dev->netdev_ops;
323 if (ops->ndo_select_queue) {
324 queue_index = ops->ndo_select_queue(dev, skb, NULL,
325 __packet_pick_tx_queue);
326 queue_index = netdev_cap_txqueue(dev, queue_index);
328 queue_index = __packet_pick_tx_queue(dev, skb);
331 skb_set_queue_mapping(skb, queue_index);
334 /* register_prot_hook must be invoked with the po->bind_lock held,
335 * or from a context in which asynchronous accesses to the packet
336 * socket is not possible (packet_create()).
338 static void register_prot_hook(struct sock *sk)
340 struct packet_sock *po = pkt_sk(sk);
344 __fanout_link(sk, po);
346 dev_add_pack(&po->prot_hook);
353 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
354 * held. If the sync parameter is true, we will temporarily drop
355 * the po->bind_lock and do a synchronize_net to make sure no
356 * asynchronous packet processing paths still refer to the elements
357 * of po->prot_hook. If the sync parameter is false, it is the
358 * callers responsibility to take care of this.
360 static void __unregister_prot_hook(struct sock *sk, bool sync)
362 struct packet_sock *po = pkt_sk(sk);
367 __fanout_unlink(sk, po);
369 __dev_remove_pack(&po->prot_hook);
374 spin_unlock(&po->bind_lock);
376 spin_lock(&po->bind_lock);
380 static void unregister_prot_hook(struct sock *sk, bool sync)
382 struct packet_sock *po = pkt_sk(sk);
385 __unregister_prot_hook(sk, sync);
388 static inline struct page * __pure pgv_to_page(void *addr)
390 if (is_vmalloc_addr(addr))
391 return vmalloc_to_page(addr);
392 return virt_to_page(addr);
395 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
397 union tpacket_uhdr h;
400 switch (po->tp_version) {
402 h.h1->tp_status = status;
403 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
406 h.h2->tp_status = status;
407 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
411 WARN(1, "TPACKET version not supported.\n");
418 static int __packet_get_status(struct packet_sock *po, void *frame)
420 union tpacket_uhdr h;
425 switch (po->tp_version) {
427 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
428 return h.h1->tp_status;
430 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
431 return h.h2->tp_status;
434 WARN(1, "TPACKET version not supported.\n");
440 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
443 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
446 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
447 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
448 return TP_STATUS_TS_RAW_HARDWARE;
450 if (ktime_to_timespec_cond(skb->tstamp, ts))
451 return TP_STATUS_TS_SOFTWARE;
456 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
459 union tpacket_uhdr h;
463 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
467 switch (po->tp_version) {
469 h.h1->tp_sec = ts.tv_sec;
470 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
473 h.h2->tp_sec = ts.tv_sec;
474 h.h2->tp_nsec = ts.tv_nsec;
478 WARN(1, "TPACKET version not supported.\n");
482 /* one flush is safe, as both fields always lie on the same cacheline */
483 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
489 static void *packet_lookup_frame(struct packet_sock *po,
490 struct packet_ring_buffer *rb,
491 unsigned int position,
494 unsigned int pg_vec_pos, frame_offset;
495 union tpacket_uhdr h;
497 pg_vec_pos = position / rb->frames_per_block;
498 frame_offset = position % rb->frames_per_block;
500 h.raw = rb->pg_vec[pg_vec_pos].buffer +
501 (frame_offset * rb->frame_size);
503 if (status != __packet_get_status(po, h.raw))
509 static void *packet_current_frame(struct packet_sock *po,
510 struct packet_ring_buffer *rb,
513 return packet_lookup_frame(po, rb, rb->head, status);
516 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
518 del_timer_sync(&pkc->retire_blk_timer);
521 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
523 struct sk_buff_head *rb_queue)
525 struct tpacket_kbdq_core *pkc;
527 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
528 GET_PBDQC_FROM_RB(&po->rx_ring);
530 spin_lock_bh(&rb_queue->lock);
531 pkc->delete_blk_timer = 1;
532 spin_unlock_bh(&rb_queue->lock);
534 prb_del_retire_blk_timer(pkc);
537 static void prb_init_blk_timer(struct packet_sock *po,
538 struct tpacket_kbdq_core *pkc,
539 void (*func) (unsigned long))
541 init_timer(&pkc->retire_blk_timer);
542 pkc->retire_blk_timer.data = (long)po;
543 pkc->retire_blk_timer.function = func;
544 pkc->retire_blk_timer.expires = jiffies;
547 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
549 struct tpacket_kbdq_core *pkc;
554 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
555 GET_PBDQC_FROM_RB(&po->rx_ring);
556 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
559 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
560 int blk_size_in_bytes)
562 struct net_device *dev;
563 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
564 struct ethtool_cmd ecmd;
569 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
570 if (unlikely(!dev)) {
572 return DEFAULT_PRB_RETIRE_TOV;
574 err = __ethtool_get_settings(dev, &ecmd);
575 speed = ethtool_cmd_speed(&ecmd);
579 * If the link speed is so slow you don't really
580 * need to worry about perf anyways
582 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
583 return DEFAULT_PRB_RETIRE_TOV;
590 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
602 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
603 union tpacket_req_u *req_u)
605 p1->feature_req_word = req_u->req3.tp_feature_req_word;
608 static void init_prb_bdqc(struct packet_sock *po,
609 struct packet_ring_buffer *rb,
611 union tpacket_req_u *req_u, int tx_ring)
613 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
614 struct tpacket_block_desc *pbd;
616 memset(p1, 0x0, sizeof(*p1));
618 p1->knxt_seq_num = 1;
620 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
621 p1->pkblk_start = pg_vec[0].buffer;
622 p1->kblk_size = req_u->req3.tp_block_size;
623 p1->knum_blocks = req_u->req3.tp_block_nr;
624 p1->hdrlen = po->tp_hdrlen;
625 p1->version = po->tp_version;
626 p1->last_kactive_blk_num = 0;
627 po->stats.stats3.tp_freeze_q_cnt = 0;
628 if (req_u->req3.tp_retire_blk_tov)
629 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
631 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
632 req_u->req3.tp_block_size);
633 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
634 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
636 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
637 prb_init_ft_ops(p1, req_u);
638 prb_setup_retire_blk_timer(po, tx_ring);
639 prb_open_block(p1, pbd);
642 /* Do NOT update the last_blk_num first.
643 * Assumes sk_buff_head lock is held.
645 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
647 mod_timer(&pkc->retire_blk_timer,
648 jiffies + pkc->tov_in_jiffies);
649 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
654 * 1) We refresh the timer only when we open a block.
655 * By doing this we don't waste cycles refreshing the timer
656 * on packet-by-packet basis.
658 * With a 1MB block-size, on a 1Gbps line, it will take
659 * i) ~8 ms to fill a block + ii) memcpy etc.
660 * In this cut we are not accounting for the memcpy time.
662 * So, if the user sets the 'tmo' to 10ms then the timer
663 * will never fire while the block is still getting filled
664 * (which is what we want). However, the user could choose
665 * to close a block early and that's fine.
667 * But when the timer does fire, we check whether or not to refresh it.
668 * Since the tmo granularity is in msecs, it is not too expensive
669 * to refresh the timer, lets say every '8' msecs.
670 * Either the user can set the 'tmo' or we can derive it based on
671 * a) line-speed and b) block-size.
672 * prb_calc_retire_blk_tmo() calculates the tmo.
675 static void prb_retire_rx_blk_timer_expired(unsigned long data)
677 struct packet_sock *po = (struct packet_sock *)data;
678 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
680 struct tpacket_block_desc *pbd;
682 spin_lock(&po->sk.sk_receive_queue.lock);
684 frozen = prb_queue_frozen(pkc);
685 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
687 if (unlikely(pkc->delete_blk_timer))
690 /* We only need to plug the race when the block is partially filled.
692 * lock(); increment BLOCK_NUM_PKTS; unlock()
693 * copy_bits() is in progress ...
694 * timer fires on other cpu:
695 * we can't retire the current block because copy_bits
699 if (BLOCK_NUM_PKTS(pbd)) {
700 while (atomic_read(&pkc->blk_fill_in_prog)) {
701 /* Waiting for skb_copy_bits to finish... */
706 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
708 if (!BLOCK_NUM_PKTS(pbd)) {
709 /* An empty block. Just refresh the timer. */
712 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
713 if (!prb_dispatch_next_block(pkc, po))
718 /* Case 1. Queue was frozen because user-space was
721 if (prb_curr_blk_in_use(pkc, pbd)) {
723 * Ok, user-space is still behind.
724 * So just refresh the timer.
728 /* Case 2. queue was frozen,user-space caught up,
729 * now the link went idle && the timer fired.
730 * We don't have a block to close.So we open this
731 * block and restart the timer.
732 * opening a block thaws the queue,restarts timer
733 * Thawing/timer-refresh is a side effect.
735 prb_open_block(pkc, pbd);
742 _prb_refresh_rx_retire_blk_timer(pkc);
745 spin_unlock(&po->sk.sk_receive_queue.lock);
748 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
749 struct tpacket_block_desc *pbd1, __u32 status)
751 /* Flush everything minus the block header */
753 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
758 /* Skip the block header(we know header WILL fit in 4K) */
761 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
762 for (; start < end; start += PAGE_SIZE)
763 flush_dcache_page(pgv_to_page(start));
768 /* Now update the block status. */
770 BLOCK_STATUS(pbd1) = status;
772 /* Flush the block header */
774 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
776 flush_dcache_page(pgv_to_page(start));
786 * 2) Increment active_blk_num
788 * Note:We DONT refresh the timer on purpose.
789 * Because almost always the next block will be opened.
791 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
792 struct tpacket_block_desc *pbd1,
793 struct packet_sock *po, unsigned int stat)
795 __u32 status = TP_STATUS_USER | stat;
797 struct tpacket3_hdr *last_pkt;
798 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
799 struct sock *sk = &po->sk;
801 if (po->stats.stats3.tp_drops)
802 status |= TP_STATUS_LOSING;
804 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
805 last_pkt->tp_next_offset = 0;
807 /* Get the ts of the last pkt */
808 if (BLOCK_NUM_PKTS(pbd1)) {
809 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
810 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
812 /* Ok, we tmo'd - so get the current time.
814 * It shouldn't really happen as we don't close empty
815 * blocks. See prb_retire_rx_blk_timer_expired().
819 h1->ts_last_pkt.ts_sec = ts.tv_sec;
820 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
825 /* Flush the block */
826 prb_flush_block(pkc1, pbd1, status);
828 sk->sk_data_ready(sk);
830 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
833 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
835 pkc->reset_pending_on_curr_blk = 0;
839 * Side effect of opening a block:
841 * 1) prb_queue is thawed.
842 * 2) retire_blk_timer is refreshed.
845 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
846 struct tpacket_block_desc *pbd1)
849 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
853 /* We could have just memset this but we will lose the
854 * flexibility of making the priv area sticky
857 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
858 BLOCK_NUM_PKTS(pbd1) = 0;
859 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
863 h1->ts_first_pkt.ts_sec = ts.tv_sec;
864 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
866 pkc1->pkblk_start = (char *)pbd1;
867 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
869 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
870 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
872 pbd1->version = pkc1->version;
873 pkc1->prev = pkc1->nxt_offset;
874 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
876 prb_thaw_queue(pkc1);
877 _prb_refresh_rx_retire_blk_timer(pkc1);
883 * Queue freeze logic:
884 * 1) Assume tp_block_nr = 8 blocks.
885 * 2) At time 't0', user opens Rx ring.
886 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
887 * 4) user-space is either sleeping or processing block '0'.
888 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
889 * it will close block-7,loop around and try to fill block '0'.
891 * __packet_lookup_frame_in_block
892 * prb_retire_current_block()
893 * prb_dispatch_next_block()
894 * |->(BLOCK_STATUS == USER) evaluates to true
895 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
896 * 6) Now there are two cases:
897 * 6.1) Link goes idle right after the queue is frozen.
898 * But remember, the last open_block() refreshed the timer.
899 * When this timer expires,it will refresh itself so that we can
900 * re-open block-0 in near future.
901 * 6.2) Link is busy and keeps on receiving packets. This is a simple
902 * case and __packet_lookup_frame_in_block will check if block-0
903 * is free and can now be re-used.
905 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
906 struct packet_sock *po)
908 pkc->reset_pending_on_curr_blk = 1;
909 po->stats.stats3.tp_freeze_q_cnt++;
912 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
915 * If the next block is free then we will dispatch it
916 * and return a good offset.
917 * Else, we will freeze the queue.
918 * So, caller must check the return value.
920 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
921 struct packet_sock *po)
923 struct tpacket_block_desc *pbd;
927 /* 1. Get current block num */
928 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
930 /* 2. If this block is currently in_use then freeze the queue */
931 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
932 prb_freeze_queue(pkc, po);
938 * open this block and return the offset where the first packet
939 * needs to get stored.
941 prb_open_block(pkc, pbd);
942 return (void *)pkc->nxt_offset;
945 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
946 struct packet_sock *po, unsigned int status)
948 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
950 /* retire/close the current block */
951 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
953 * Plug the case where copy_bits() is in progress on
954 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
955 * have space to copy the pkt in the current block and
956 * called prb_retire_current_block()
958 * We don't need to worry about the TMO case because
959 * the timer-handler already handled this case.
961 if (!(status & TP_STATUS_BLK_TMO)) {
962 while (atomic_read(&pkc->blk_fill_in_prog)) {
963 /* Waiting for skb_copy_bits to finish... */
967 prb_close_block(pkc, pbd, po, status);
972 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
973 struct tpacket_block_desc *pbd)
975 return TP_STATUS_USER & BLOCK_STATUS(pbd);
978 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
980 return pkc->reset_pending_on_curr_blk;
983 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
985 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
986 atomic_dec(&pkc->blk_fill_in_prog);
989 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
990 struct tpacket3_hdr *ppd)
992 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
995 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
996 struct tpacket3_hdr *ppd)
998 ppd->hv1.tp_rxhash = 0;
1001 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
1002 struct tpacket3_hdr *ppd)
1004 if (skb_vlan_tag_present(pkc->skb)) {
1005 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1006 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1007 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1009 ppd->hv1.tp_vlan_tci = 0;
1010 ppd->hv1.tp_vlan_tpid = 0;
1011 ppd->tp_status = TP_STATUS_AVAILABLE;
1015 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1016 struct tpacket3_hdr *ppd)
1018 ppd->hv1.tp_padding = 0;
1019 prb_fill_vlan_info(pkc, ppd);
1021 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1022 prb_fill_rxhash(pkc, ppd);
1024 prb_clear_rxhash(pkc, ppd);
1027 static void prb_fill_curr_block(char *curr,
1028 struct tpacket_kbdq_core *pkc,
1029 struct tpacket_block_desc *pbd,
1032 struct tpacket3_hdr *ppd;
1034 ppd = (struct tpacket3_hdr *)curr;
1035 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1037 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1038 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1039 BLOCK_NUM_PKTS(pbd) += 1;
1040 atomic_inc(&pkc->blk_fill_in_prog);
1041 prb_run_all_ft_ops(pkc, ppd);
1044 /* Assumes caller has the sk->rx_queue.lock */
1045 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1046 struct sk_buff *skb,
1051 struct tpacket_kbdq_core *pkc;
1052 struct tpacket_block_desc *pbd;
1055 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1056 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1058 /* Queue is frozen when user space is lagging behind */
1059 if (prb_queue_frozen(pkc)) {
1061 * Check if that last block which caused the queue to freeze,
1062 * is still in_use by user-space.
1064 if (prb_curr_blk_in_use(pkc, pbd)) {
1065 /* Can't record this packet */
1069 * Ok, the block was released by user-space.
1070 * Now let's open that block.
1071 * opening a block also thaws the queue.
1072 * Thawing is a side effect.
1074 prb_open_block(pkc, pbd);
1079 curr = pkc->nxt_offset;
1081 end = (char *)pbd + pkc->kblk_size;
1083 /* first try the current block */
1084 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1085 prb_fill_curr_block(curr, pkc, pbd, len);
1086 return (void *)curr;
1089 /* Ok, close the current block */
1090 prb_retire_current_block(pkc, po, 0);
1092 /* Now, try to dispatch the next block */
1093 curr = (char *)prb_dispatch_next_block(pkc, po);
1095 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1096 prb_fill_curr_block(curr, pkc, pbd, len);
1097 return (void *)curr;
1101 * No free blocks are available.user_space hasn't caught up yet.
1102 * Queue was just frozen and now this packet will get dropped.
1107 static void *packet_current_rx_frame(struct packet_sock *po,
1108 struct sk_buff *skb,
1109 int status, unsigned int len)
1112 switch (po->tp_version) {
1115 curr = packet_lookup_frame(po, &po->rx_ring,
1116 po->rx_ring.head, status);
1119 return __packet_lookup_frame_in_block(po, skb, status, len);
1121 WARN(1, "TPACKET version not supported\n");
1127 static void *prb_lookup_block(struct packet_sock *po,
1128 struct packet_ring_buffer *rb,
1132 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1133 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1135 if (status != BLOCK_STATUS(pbd))
1140 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1143 if (rb->prb_bdqc.kactive_blk_num)
1144 prev = rb->prb_bdqc.kactive_blk_num-1;
1146 prev = rb->prb_bdqc.knum_blocks-1;
1150 /* Assumes caller has held the rx_queue.lock */
1151 static void *__prb_previous_block(struct packet_sock *po,
1152 struct packet_ring_buffer *rb,
1155 unsigned int previous = prb_previous_blk_num(rb);
1156 return prb_lookup_block(po, rb, previous, status);
1159 static void *packet_previous_rx_frame(struct packet_sock *po,
1160 struct packet_ring_buffer *rb,
1163 if (po->tp_version <= TPACKET_V2)
1164 return packet_previous_frame(po, rb, status);
1166 return __prb_previous_block(po, rb, status);
1169 static void packet_increment_rx_head(struct packet_sock *po,
1170 struct packet_ring_buffer *rb)
1172 switch (po->tp_version) {
1175 return packet_increment_head(rb);
1178 WARN(1, "TPACKET version not supported.\n");
1184 static void *packet_previous_frame(struct packet_sock *po,
1185 struct packet_ring_buffer *rb,
1188 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1189 return packet_lookup_frame(po, rb, previous, status);
1192 static void packet_increment_head(struct packet_ring_buffer *buff)
1194 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1197 static void packet_inc_pending(struct packet_ring_buffer *rb)
1199 this_cpu_inc(*rb->pending_refcnt);
1202 static void packet_dec_pending(struct packet_ring_buffer *rb)
1204 this_cpu_dec(*rb->pending_refcnt);
1207 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1209 unsigned int refcnt = 0;
1212 /* We don't use pending refcount in rx_ring. */
1213 if (rb->pending_refcnt == NULL)
1216 for_each_possible_cpu(cpu)
1217 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1222 static int packet_alloc_pending(struct packet_sock *po)
1224 po->rx_ring.pending_refcnt = NULL;
1226 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1227 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1233 static void packet_free_pending(struct packet_sock *po)
1235 free_percpu(po->tx_ring.pending_refcnt);
1238 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1240 struct sock *sk = &po->sk;
1243 if (po->prot_hook.func != tpacket_rcv)
1244 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1247 spin_lock(&sk->sk_receive_queue.lock);
1248 if (po->tp_version == TPACKET_V3)
1249 has_room = prb_lookup_block(po, &po->rx_ring,
1250 po->rx_ring.prb_bdqc.kactive_blk_num,
1253 has_room = packet_lookup_frame(po, &po->rx_ring,
1256 spin_unlock(&sk->sk_receive_queue.lock);
1261 static void packet_sock_destruct(struct sock *sk)
1263 skb_queue_purge(&sk->sk_error_queue);
1265 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1266 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1268 if (!sock_flag(sk, SOCK_DEAD)) {
1269 pr_err("Attempt to release alive packet socket: %p\n", sk);
1273 sk_refcnt_debug_dec(sk);
1276 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1277 struct sk_buff *skb,
1280 return reciprocal_scale(skb_get_hash(skb), num);
1283 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1284 struct sk_buff *skb,
1287 unsigned int val = atomic_inc_return(&f->rr_cur);
1292 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1293 struct sk_buff *skb,
1296 return smp_processor_id() % num;
1299 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1300 struct sk_buff *skb,
1303 return prandom_u32_max(num);
1306 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1307 struct sk_buff *skb,
1308 unsigned int idx, unsigned int skip,
1313 i = j = min_t(int, f->next[idx], num - 1);
1315 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1327 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1328 struct sk_buff *skb,
1331 return skb_get_queue_mapping(skb) % num;
1334 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1336 return f->flags & (flag >> 8);
1339 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1340 struct packet_type *pt, struct net_device *orig_dev)
1342 struct packet_fanout *f = pt->af_packet_priv;
1343 unsigned int num = READ_ONCE(f->num_members);
1344 struct packet_sock *po;
1347 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1353 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1354 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1359 case PACKET_FANOUT_HASH:
1361 idx = fanout_demux_hash(f, skb, num);
1363 case PACKET_FANOUT_LB:
1364 idx = fanout_demux_lb(f, skb, num);
1366 case PACKET_FANOUT_CPU:
1367 idx = fanout_demux_cpu(f, skb, num);
1369 case PACKET_FANOUT_RND:
1370 idx = fanout_demux_rnd(f, skb, num);
1372 case PACKET_FANOUT_QM:
1373 idx = fanout_demux_qm(f, skb, num);
1375 case PACKET_FANOUT_ROLLOVER:
1376 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1380 po = pkt_sk(f->arr[idx]);
1381 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1382 unlikely(!packet_rcv_has_room(po, skb))) {
1383 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1384 po = pkt_sk(f->arr[idx]);
1387 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1390 DEFINE_MUTEX(fanout_mutex);
1391 EXPORT_SYMBOL_GPL(fanout_mutex);
1392 static LIST_HEAD(fanout_list);
1394 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1396 struct packet_fanout *f = po->fanout;
1398 spin_lock(&f->lock);
1399 f->arr[f->num_members] = sk;
1402 spin_unlock(&f->lock);
1405 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1407 struct packet_fanout *f = po->fanout;
1410 spin_lock(&f->lock);
1411 for (i = 0; i < f->num_members; i++) {
1412 if (f->arr[i] == sk)
1415 BUG_ON(i >= f->num_members);
1416 f->arr[i] = f->arr[f->num_members - 1];
1418 spin_unlock(&f->lock);
1421 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1423 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1429 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1431 struct packet_sock *po = pkt_sk(sk);
1432 struct packet_fanout *f, *match;
1433 u8 type = type_flags & 0xff;
1434 u8 flags = type_flags >> 8;
1438 case PACKET_FANOUT_ROLLOVER:
1439 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1441 case PACKET_FANOUT_HASH:
1442 case PACKET_FANOUT_LB:
1443 case PACKET_FANOUT_CPU:
1444 case PACKET_FANOUT_RND:
1445 case PACKET_FANOUT_QM:
1457 mutex_lock(&fanout_mutex);
1459 list_for_each_entry(f, &fanout_list, list) {
1461 read_pnet(&f->net) == sock_net(sk)) {
1467 if (match && match->flags != flags)
1471 match = kzalloc(sizeof(*match), GFP_KERNEL);
1474 write_pnet(&match->net, sock_net(sk));
1477 match->flags = flags;
1478 atomic_set(&match->rr_cur, 0);
1479 INIT_LIST_HEAD(&match->list);
1480 spin_lock_init(&match->lock);
1481 atomic_set(&match->sk_ref, 0);
1482 match->prot_hook.type = po->prot_hook.type;
1483 match->prot_hook.dev = po->prot_hook.dev;
1484 match->prot_hook.func = packet_rcv_fanout;
1485 match->prot_hook.af_packet_priv = match;
1486 match->prot_hook.id_match = match_fanout_group;
1487 dev_add_pack(&match->prot_hook);
1488 list_add(&match->list, &fanout_list);
1491 if (match->type == type &&
1492 match->prot_hook.type == po->prot_hook.type &&
1493 match->prot_hook.dev == po->prot_hook.dev) {
1495 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1496 __dev_remove_pack(&po->prot_hook);
1498 atomic_inc(&match->sk_ref);
1499 __fanout_link(sk, po);
1504 mutex_unlock(&fanout_mutex);
1508 static void fanout_release(struct sock *sk)
1510 struct packet_sock *po = pkt_sk(sk);
1511 struct packet_fanout *f;
1517 mutex_lock(&fanout_mutex);
1520 if (atomic_dec_and_test(&f->sk_ref)) {
1522 dev_remove_pack(&f->prot_hook);
1525 mutex_unlock(&fanout_mutex);
1528 static const struct proto_ops packet_ops;
1530 static const struct proto_ops packet_ops_spkt;
1532 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1533 struct packet_type *pt, struct net_device *orig_dev)
1536 struct sockaddr_pkt *spkt;
1539 * When we registered the protocol we saved the socket in the data
1540 * field for just this event.
1543 sk = pt->af_packet_priv;
1546 * Yank back the headers [hope the device set this
1547 * right or kerboom...]
1549 * Incoming packets have ll header pulled,
1552 * For outgoing ones skb->data == skb_mac_header(skb)
1553 * so that this procedure is noop.
1556 if (skb->pkt_type == PACKET_LOOPBACK)
1559 if (!net_eq(dev_net(dev), sock_net(sk)))
1562 skb = skb_share_check(skb, GFP_ATOMIC);
1566 /* drop any routing info */
1569 /* drop conntrack reference */
1572 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1574 skb_push(skb, skb->data - skb_mac_header(skb));
1577 * The SOCK_PACKET socket receives _all_ frames.
1580 spkt->spkt_family = dev->type;
1581 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1582 spkt->spkt_protocol = skb->protocol;
1585 * Charge the memory to the socket. This is done specifically
1586 * to prevent sockets using all the memory up.
1589 if (sock_queue_rcv_skb(sk, skb) == 0)
1600 * Output a raw packet to a device layer. This bypasses all the other
1601 * protocol layers and you must therefore supply it with a complete frame
1604 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1607 struct sock *sk = sock->sk;
1608 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1609 struct sk_buff *skb = NULL;
1610 struct net_device *dev;
1616 * Get and verify the address.
1620 if (msg->msg_namelen < sizeof(struct sockaddr))
1622 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1623 proto = saddr->spkt_protocol;
1625 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1628 * Find the device first to size check it
1631 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1634 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1640 if (!(dev->flags & IFF_UP))
1644 * You may not queue a frame bigger than the mtu. This is the lowest level
1645 * raw protocol and you must do your own fragmentation at this level.
1648 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1649 if (!netif_supports_nofcs(dev)) {
1650 err = -EPROTONOSUPPORT;
1653 extra_len = 4; /* We're doing our own CRC */
1657 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1661 size_t reserved = LL_RESERVED_SPACE(dev);
1662 int tlen = dev->needed_tailroom;
1663 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1666 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1669 /* FIXME: Save some space for broken drivers that write a hard
1670 * header at transmission time by themselves. PPP is the notable
1671 * one here. This should really be fixed at the driver level.
1673 skb_reserve(skb, reserved);
1674 skb_reset_network_header(skb);
1676 /* Try to align data part correctly */
1681 skb_reset_network_header(skb);
1683 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1689 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1690 /* Earlier code assumed this would be a VLAN pkt,
1691 * double-check this now that we have the actual
1694 struct ethhdr *ehdr;
1695 skb_reset_mac_header(skb);
1696 ehdr = eth_hdr(skb);
1697 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1703 skb->protocol = proto;
1705 skb->priority = sk->sk_priority;
1706 skb->mark = sk->sk_mark;
1708 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1710 if (unlikely(extra_len == 4))
1713 skb_probe_transport_header(skb, 0);
1715 dev_queue_xmit(skb);
1726 static unsigned int run_filter(const struct sk_buff *skb,
1727 const struct sock *sk,
1730 struct sk_filter *filter;
1733 filter = rcu_dereference(sk->sk_filter);
1735 res = SK_RUN_FILTER(filter, skb);
1742 * This function makes lazy skb cloning in hope that most of packets
1743 * are discarded by BPF.
1745 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1746 * and skb->cb are mangled. It works because (and until) packets
1747 * falling here are owned by current CPU. Output packets are cloned
1748 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1749 * sequencially, so that if we return skb to original state on exit,
1750 * we will not harm anyone.
1753 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1754 struct packet_type *pt, struct net_device *orig_dev)
1757 struct sockaddr_ll *sll;
1758 struct packet_sock *po;
1759 u8 *skb_head = skb->data;
1760 int skb_len = skb->len;
1761 unsigned int snaplen, res;
1763 if (skb->pkt_type == PACKET_LOOPBACK)
1766 sk = pt->af_packet_priv;
1769 if (!net_eq(dev_net(dev), sock_net(sk)))
1774 if (dev->header_ops) {
1775 /* The device has an explicit notion of ll header,
1776 * exported to higher levels.
1778 * Otherwise, the device hides details of its frame
1779 * structure, so that corresponding packet head is
1780 * never delivered to user.
1782 if (sk->sk_type != SOCK_DGRAM)
1783 skb_push(skb, skb->data - skb_mac_header(skb));
1784 else if (skb->pkt_type == PACKET_OUTGOING) {
1785 /* Special case: outgoing packets have ll header at head */
1786 skb_pull(skb, skb_network_offset(skb));
1792 res = run_filter(skb, sk, snaplen);
1794 goto drop_n_restore;
1798 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1801 if (skb_shared(skb)) {
1802 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1806 if (skb_head != skb->data) {
1807 skb->data = skb_head;
1814 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
1816 sll = &PACKET_SKB_CB(skb)->sa.ll;
1817 sll->sll_hatype = dev->type;
1818 sll->sll_pkttype = skb->pkt_type;
1819 if (unlikely(po->origdev))
1820 sll->sll_ifindex = orig_dev->ifindex;
1822 sll->sll_ifindex = dev->ifindex;
1824 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1826 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
1827 * Use their space for storing the original skb length.
1829 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
1831 if (pskb_trim(skb, snaplen))
1834 skb_set_owner_r(skb, sk);
1838 /* drop conntrack reference */
1841 spin_lock(&sk->sk_receive_queue.lock);
1842 po->stats.stats1.tp_packets++;
1843 sock_skb_set_dropcount(sk, skb);
1844 __skb_queue_tail(&sk->sk_receive_queue, skb);
1845 spin_unlock(&sk->sk_receive_queue.lock);
1846 sk->sk_data_ready(sk);
1850 spin_lock(&sk->sk_receive_queue.lock);
1851 po->stats.stats1.tp_drops++;
1852 atomic_inc(&sk->sk_drops);
1853 spin_unlock(&sk->sk_receive_queue.lock);
1856 if (skb_head != skb->data && skb_shared(skb)) {
1857 skb->data = skb_head;
1865 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1866 struct packet_type *pt, struct net_device *orig_dev)
1869 struct packet_sock *po;
1870 struct sockaddr_ll *sll;
1871 union tpacket_uhdr h;
1872 u8 *skb_head = skb->data;
1873 int skb_len = skb->len;
1874 unsigned int snaplen, res;
1875 unsigned long status = TP_STATUS_USER;
1876 unsigned short macoff, netoff, hdrlen;
1877 struct sk_buff *copy_skb = NULL;
1881 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
1882 * We may add members to them until current aligned size without forcing
1883 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
1885 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
1886 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
1888 if (skb->pkt_type == PACKET_LOOPBACK)
1891 sk = pt->af_packet_priv;
1894 if (!net_eq(dev_net(dev), sock_net(sk)))
1897 if (dev->header_ops) {
1898 if (sk->sk_type != SOCK_DGRAM)
1899 skb_push(skb, skb->data - skb_mac_header(skb));
1900 else if (skb->pkt_type == PACKET_OUTGOING) {
1901 /* Special case: outgoing packets have ll header at head */
1902 skb_pull(skb, skb_network_offset(skb));
1908 res = run_filter(skb, sk, snaplen);
1910 goto drop_n_restore;
1912 if (skb->ip_summed == CHECKSUM_PARTIAL)
1913 status |= TP_STATUS_CSUMNOTREADY;
1914 else if (skb->pkt_type != PACKET_OUTGOING &&
1915 (skb->ip_summed == CHECKSUM_COMPLETE ||
1916 skb_csum_unnecessary(skb)))
1917 status |= TP_STATUS_CSUM_VALID;
1922 if (sk->sk_type == SOCK_DGRAM) {
1923 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1926 unsigned int maclen = skb_network_offset(skb);
1927 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1928 (maclen < 16 ? 16 : maclen)) +
1930 macoff = netoff - maclen;
1932 if (po->tp_version <= TPACKET_V2) {
1933 if (macoff + snaplen > po->rx_ring.frame_size) {
1934 if (po->copy_thresh &&
1935 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1936 if (skb_shared(skb)) {
1937 copy_skb = skb_clone(skb, GFP_ATOMIC);
1939 copy_skb = skb_get(skb);
1940 skb_head = skb->data;
1943 skb_set_owner_r(copy_skb, sk);
1945 snaplen = po->rx_ring.frame_size - macoff;
1946 if ((int)snaplen < 0)
1949 } else if (unlikely(macoff + snaplen >
1950 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
1953 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
1954 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
1955 snaplen, nval, macoff);
1957 if (unlikely((int)snaplen < 0)) {
1959 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
1962 spin_lock(&sk->sk_receive_queue.lock);
1963 h.raw = packet_current_rx_frame(po, skb,
1964 TP_STATUS_KERNEL, (macoff+snaplen));
1967 if (po->tp_version <= TPACKET_V2) {
1968 packet_increment_rx_head(po, &po->rx_ring);
1970 * LOSING will be reported till you read the stats,
1971 * because it's COR - Clear On Read.
1972 * Anyways, moving it for V1/V2 only as V3 doesn't need this
1975 if (po->stats.stats1.tp_drops)
1976 status |= TP_STATUS_LOSING;
1978 po->stats.stats1.tp_packets++;
1980 status |= TP_STATUS_COPY;
1981 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1983 spin_unlock(&sk->sk_receive_queue.lock);
1985 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1987 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1988 getnstimeofday(&ts);
1990 status |= ts_status;
1992 switch (po->tp_version) {
1994 h.h1->tp_len = skb->len;
1995 h.h1->tp_snaplen = snaplen;
1996 h.h1->tp_mac = macoff;
1997 h.h1->tp_net = netoff;
1998 h.h1->tp_sec = ts.tv_sec;
1999 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2000 hdrlen = sizeof(*h.h1);
2003 h.h2->tp_len = skb->len;
2004 h.h2->tp_snaplen = snaplen;
2005 h.h2->tp_mac = macoff;
2006 h.h2->tp_net = netoff;
2007 h.h2->tp_sec = ts.tv_sec;
2008 h.h2->tp_nsec = ts.tv_nsec;
2009 if (skb_vlan_tag_present(skb)) {
2010 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2011 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2012 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2014 h.h2->tp_vlan_tci = 0;
2015 h.h2->tp_vlan_tpid = 0;
2017 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2018 hdrlen = sizeof(*h.h2);
2021 /* tp_nxt_offset,vlan are already populated above.
2022 * So DONT clear those fields here
2024 h.h3->tp_status |= status;
2025 h.h3->tp_len = skb->len;
2026 h.h3->tp_snaplen = snaplen;
2027 h.h3->tp_mac = macoff;
2028 h.h3->tp_net = netoff;
2029 h.h3->tp_sec = ts.tv_sec;
2030 h.h3->tp_nsec = ts.tv_nsec;
2031 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2032 hdrlen = sizeof(*h.h3);
2038 sll = h.raw + TPACKET_ALIGN(hdrlen);
2039 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2040 sll->sll_family = AF_PACKET;
2041 sll->sll_hatype = dev->type;
2042 sll->sll_protocol = skb->protocol;
2043 sll->sll_pkttype = skb->pkt_type;
2044 if (unlikely(po->origdev))
2045 sll->sll_ifindex = orig_dev->ifindex;
2047 sll->sll_ifindex = dev->ifindex;
2051 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2052 if (po->tp_version <= TPACKET_V2) {
2055 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2058 for (start = h.raw; start < end; start += PAGE_SIZE)
2059 flush_dcache_page(pgv_to_page(start));
2064 if (po->tp_version <= TPACKET_V2) {
2065 __packet_set_status(po, h.raw, status);
2066 sk->sk_data_ready(sk);
2068 prb_clear_blk_fill_status(&po->rx_ring);
2072 if (skb_head != skb->data && skb_shared(skb)) {
2073 skb->data = skb_head;
2081 po->stats.stats1.tp_drops++;
2082 spin_unlock(&sk->sk_receive_queue.lock);
2084 sk->sk_data_ready(sk);
2085 kfree_skb(copy_skb);
2086 goto drop_n_restore;
2089 static void tpacket_destruct_skb(struct sk_buff *skb)
2091 struct packet_sock *po = pkt_sk(skb->sk);
2093 if (likely(po->tx_ring.pg_vec)) {
2097 ph = skb_shinfo(skb)->destructor_arg;
2098 packet_dec_pending(&po->tx_ring);
2100 ts = __packet_set_timestamp(po, ph, skb);
2101 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2107 static bool ll_header_truncated(const struct net_device *dev, int len)
2109 /* net device doesn't like empty head */
2110 if (unlikely(len <= dev->hard_header_len)) {
2111 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n",
2112 current->comm, len, dev->hard_header_len);
2119 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2120 void *frame, struct net_device *dev, int size_max,
2121 __be16 proto, unsigned char *addr, int hlen)
2123 union tpacket_uhdr ph;
2124 int to_write, offset, len, tp_len, nr_frags, len_max;
2125 struct socket *sock = po->sk.sk_socket;
2132 skb->protocol = proto;
2134 skb->priority = po->sk.sk_priority;
2135 skb->mark = po->sk.sk_mark;
2136 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2137 skb_shinfo(skb)->destructor_arg = ph.raw;
2139 switch (po->tp_version) {
2141 tp_len = ph.h2->tp_len;
2144 tp_len = ph.h1->tp_len;
2147 if (unlikely(tp_len > size_max)) {
2148 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2152 skb_reserve(skb, hlen);
2153 skb_reset_network_header(skb);
2155 if (!packet_use_direct_xmit(po))
2156 skb_probe_transport_header(skb, 0);
2157 if (unlikely(po->tp_tx_has_off)) {
2158 int off_min, off_max, off;
2159 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2160 off_max = po->tx_ring.frame_size - tp_len;
2161 if (sock->type == SOCK_DGRAM) {
2162 switch (po->tp_version) {
2164 off = ph.h2->tp_net;
2167 off = ph.h1->tp_net;
2171 switch (po->tp_version) {
2173 off = ph.h2->tp_mac;
2176 off = ph.h1->tp_mac;
2180 if (unlikely((off < off_min) || (off_max < off)))
2182 data = ph.raw + off;
2184 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2188 if (sock->type == SOCK_DGRAM) {
2189 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2191 if (unlikely(err < 0))
2193 } else if (dev->hard_header_len) {
2194 if (ll_header_truncated(dev, tp_len))
2197 skb_push(skb, dev->hard_header_len);
2198 err = skb_store_bits(skb, 0, data,
2199 dev->hard_header_len);
2203 data += dev->hard_header_len;
2204 to_write -= dev->hard_header_len;
2207 offset = offset_in_page(data);
2208 len_max = PAGE_SIZE - offset;
2209 len = ((to_write > len_max) ? len_max : to_write);
2211 skb->data_len = to_write;
2212 skb->len += to_write;
2213 skb->truesize += to_write;
2214 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2216 while (likely(to_write)) {
2217 nr_frags = skb_shinfo(skb)->nr_frags;
2219 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2220 pr_err("Packet exceed the number of skb frags(%lu)\n",
2225 page = pgv_to_page(data);
2227 flush_dcache_page(page);
2229 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2232 len_max = PAGE_SIZE;
2233 len = ((to_write > len_max) ? len_max : to_write);
2239 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2241 struct sk_buff *skb;
2242 struct net_device *dev;
2244 int err, reserve = 0;
2246 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2247 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2248 int tp_len, size_max;
2249 unsigned char *addr;
2251 int status = TP_STATUS_AVAILABLE;
2254 mutex_lock(&po->pg_vec_lock);
2256 if (likely(saddr == NULL)) {
2257 dev = packet_cached_dev_get(po);
2262 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2264 if (msg->msg_namelen < (saddr->sll_halen
2265 + offsetof(struct sockaddr_ll,
2268 proto = saddr->sll_protocol;
2269 addr = saddr->sll_addr;
2270 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2274 if (unlikely(dev == NULL))
2277 if (unlikely(!(dev->flags & IFF_UP)))
2280 reserve = dev->hard_header_len + VLAN_HLEN;
2281 size_max = po->tx_ring.frame_size
2282 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2284 if (size_max > dev->mtu + reserve)
2285 size_max = dev->mtu + reserve;
2288 ph = packet_current_frame(po, &po->tx_ring,
2289 TP_STATUS_SEND_REQUEST);
2290 if (unlikely(ph == NULL)) {
2291 if (need_wait && need_resched())
2296 status = TP_STATUS_SEND_REQUEST;
2297 hlen = LL_RESERVED_SPACE(dev);
2298 tlen = dev->needed_tailroom;
2299 skb = sock_alloc_send_skb(&po->sk,
2300 hlen + tlen + sizeof(struct sockaddr_ll),
2303 if (unlikely(skb == NULL)) {
2304 /* we assume the socket was initially writeable ... */
2305 if (likely(len_sum > 0))
2309 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2311 if (likely(tp_len >= 0) &&
2312 tp_len > dev->mtu + dev->hard_header_len) {
2313 struct ethhdr *ehdr;
2314 /* Earlier code assumed this would be a VLAN pkt,
2315 * double-check this now that we have the actual
2319 skb_reset_mac_header(skb);
2320 ehdr = eth_hdr(skb);
2321 if (ehdr->h_proto != htons(ETH_P_8021Q))
2324 if (unlikely(tp_len < 0)) {
2326 __packet_set_status(po, ph,
2327 TP_STATUS_AVAILABLE);
2328 packet_increment_head(&po->tx_ring);
2332 status = TP_STATUS_WRONG_FORMAT;
2338 packet_pick_tx_queue(dev, skb);
2340 skb->destructor = tpacket_destruct_skb;
2341 __packet_set_status(po, ph, TP_STATUS_SENDING);
2342 packet_inc_pending(&po->tx_ring);
2344 status = TP_STATUS_SEND_REQUEST;
2345 err = po->xmit(skb);
2346 if (unlikely(err > 0)) {
2347 err = net_xmit_errno(err);
2348 if (err && __packet_get_status(po, ph) ==
2349 TP_STATUS_AVAILABLE) {
2350 /* skb was destructed already */
2355 * skb was dropped but not destructed yet;
2356 * let's treat it like congestion or err < 0
2360 packet_increment_head(&po->tx_ring);
2362 } while (likely((ph != NULL) ||
2363 /* Note: packet_read_pending() might be slow if we have
2364 * to call it as it's per_cpu variable, but in fast-path
2365 * we already short-circuit the loop with the first
2366 * condition, and luckily don't have to go that path
2369 (need_wait && packet_read_pending(&po->tx_ring))));
2375 __packet_set_status(po, ph, status);
2380 mutex_unlock(&po->pg_vec_lock);
2384 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2385 size_t reserve, size_t len,
2386 size_t linear, int noblock,
2389 struct sk_buff *skb;
2391 /* Under a page? Don't bother with paged skb. */
2392 if (prepad + len < PAGE_SIZE || !linear)
2395 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2400 skb_reserve(skb, reserve);
2401 skb_put(skb, linear);
2402 skb->data_len = len - linear;
2403 skb->len += len - linear;
2408 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2410 struct sock *sk = sock->sk;
2411 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2412 struct sk_buff *skb;
2413 struct net_device *dev;
2415 unsigned char *addr;
2416 int err, reserve = 0;
2417 struct virtio_net_hdr vnet_hdr = { 0 };
2420 struct packet_sock *po = pkt_sk(sk);
2421 unsigned short gso_type = 0;
2427 * Get and verify the address.
2430 if (likely(saddr == NULL)) {
2431 dev = packet_cached_dev_get(po);
2436 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2438 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2440 proto = saddr->sll_protocol;
2441 addr = saddr->sll_addr;
2442 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2446 if (unlikely(dev == NULL))
2449 if (unlikely(!(dev->flags & IFF_UP)))
2452 if (sock->type == SOCK_RAW)
2453 reserve = dev->hard_header_len;
2454 if (po->has_vnet_hdr) {
2455 vnet_hdr_len = sizeof(vnet_hdr);
2458 if (len < vnet_hdr_len)
2461 len -= vnet_hdr_len;
2464 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter);
2465 if (n != vnet_hdr_len)
2468 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2469 (__virtio16_to_cpu(false, vnet_hdr.csum_start) +
2470 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 >
2471 __virtio16_to_cpu(false, vnet_hdr.hdr_len)))
2472 vnet_hdr.hdr_len = __cpu_to_virtio16(false,
2473 __virtio16_to_cpu(false, vnet_hdr.csum_start) +
2474 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2);
2477 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len)
2480 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2481 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2482 case VIRTIO_NET_HDR_GSO_TCPV4:
2483 gso_type = SKB_GSO_TCPV4;
2485 case VIRTIO_NET_HDR_GSO_TCPV6:
2486 gso_type = SKB_GSO_TCPV6;
2488 case VIRTIO_NET_HDR_GSO_UDP:
2489 gso_type = SKB_GSO_UDP;
2495 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2496 gso_type |= SKB_GSO_TCP_ECN;
2498 if (vnet_hdr.gso_size == 0)
2504 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2505 if (!netif_supports_nofcs(dev)) {
2506 err = -EPROTONOSUPPORT;
2509 extra_len = 4; /* We're doing our own CRC */
2513 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2517 hlen = LL_RESERVED_SPACE(dev);
2518 tlen = dev->needed_tailroom;
2519 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2520 __virtio16_to_cpu(false, vnet_hdr.hdr_len),
2521 msg->msg_flags & MSG_DONTWAIT, &err);
2525 skb_set_network_header(skb, reserve);
2528 if (sock->type == SOCK_DGRAM) {
2529 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2530 if (unlikely(offset < 0))
2533 if (ll_header_truncated(dev, len))
2537 /* Returns -EFAULT on error */
2538 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2542 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2544 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2545 /* Earlier code assumed this would be a VLAN pkt,
2546 * double-check this now that we have the actual
2549 struct ethhdr *ehdr;
2550 skb_reset_mac_header(skb);
2551 ehdr = eth_hdr(skb);
2552 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2558 skb->protocol = proto;
2560 skb->priority = sk->sk_priority;
2561 skb->mark = sk->sk_mark;
2563 packet_pick_tx_queue(dev, skb);
2565 if (po->has_vnet_hdr) {
2566 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2567 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start);
2568 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset);
2569 if (!skb_partial_csum_set(skb, s, o)) {
2575 skb_shinfo(skb)->gso_size =
2576 __virtio16_to_cpu(false, vnet_hdr.gso_size);
2577 skb_shinfo(skb)->gso_type = gso_type;
2579 /* Header must be checked, and gso_segs computed. */
2580 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2581 skb_shinfo(skb)->gso_segs = 0;
2583 len += vnet_hdr_len;
2586 if (!packet_use_direct_xmit(po))
2587 skb_probe_transport_header(skb, reserve);
2588 if (unlikely(extra_len == 4))
2591 err = po->xmit(skb);
2592 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2608 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2610 struct sock *sk = sock->sk;
2611 struct packet_sock *po = pkt_sk(sk);
2613 if (po->tx_ring.pg_vec)
2614 return tpacket_snd(po, msg);
2616 return packet_snd(sock, msg, len);
2620 * Close a PACKET socket. This is fairly simple. We immediately go
2621 * to 'closed' state and remove our protocol entry in the device list.
2624 static int packet_release(struct socket *sock)
2626 struct sock *sk = sock->sk;
2627 struct packet_sock *po;
2629 union tpacket_req_u req_u;
2637 mutex_lock(&net->packet.sklist_lock);
2638 sk_del_node_init_rcu(sk);
2639 mutex_unlock(&net->packet.sklist_lock);
2642 sock_prot_inuse_add(net, sk->sk_prot, -1);
2645 spin_lock(&po->bind_lock);
2646 unregister_prot_hook(sk, false);
2647 packet_cached_dev_reset(po);
2649 if (po->prot_hook.dev) {
2650 dev_put(po->prot_hook.dev);
2651 po->prot_hook.dev = NULL;
2653 spin_unlock(&po->bind_lock);
2655 packet_flush_mclist(sk);
2657 if (po->rx_ring.pg_vec) {
2658 memset(&req_u, 0, sizeof(req_u));
2659 packet_set_ring(sk, &req_u, 1, 0);
2662 if (po->tx_ring.pg_vec) {
2663 memset(&req_u, 0, sizeof(req_u));
2664 packet_set_ring(sk, &req_u, 1, 1);
2671 * Now the socket is dead. No more input will appear.
2678 skb_queue_purge(&sk->sk_receive_queue);
2679 packet_free_pending(po);
2680 sk_refcnt_debug_release(sk);
2687 * Attach a packet hook.
2690 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2692 struct packet_sock *po = pkt_sk(sk);
2693 struct net_device *dev_curr;
2705 spin_lock(&po->bind_lock);
2707 proto_curr = po->prot_hook.type;
2708 dev_curr = po->prot_hook.dev;
2710 need_rehook = proto_curr != proto || dev_curr != dev;
2713 unregister_prot_hook(sk, true);
2716 po->prot_hook.type = proto;
2717 po->prot_hook.dev = dev;
2719 po->ifindex = dev ? dev->ifindex : 0;
2720 packet_cached_dev_assign(po, dev);
2725 if (proto == 0 || !need_rehook)
2728 if (!dev || (dev->flags & IFF_UP)) {
2729 register_prot_hook(sk);
2731 sk->sk_err = ENETDOWN;
2732 if (!sock_flag(sk, SOCK_DEAD))
2733 sk->sk_error_report(sk);
2737 spin_unlock(&po->bind_lock);
2743 * Bind a packet socket to a device
2746 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2749 struct sock *sk = sock->sk;
2751 struct net_device *dev;
2758 if (addr_len != sizeof(struct sockaddr))
2760 strlcpy(name, uaddr->sa_data, sizeof(name));
2762 dev = dev_get_by_name(sock_net(sk), name);
2764 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2768 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2770 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2771 struct sock *sk = sock->sk;
2772 struct net_device *dev = NULL;
2780 if (addr_len < sizeof(struct sockaddr_ll))
2782 if (sll->sll_family != AF_PACKET)
2785 if (sll->sll_ifindex) {
2787 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2791 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2797 static struct proto packet_proto = {
2799 .owner = THIS_MODULE,
2800 .obj_size = sizeof(struct packet_sock),
2804 * Create a packet of type SOCK_PACKET.
2807 static int packet_create(struct net *net, struct socket *sock, int protocol,
2811 struct packet_sock *po;
2812 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2815 if (!ns_capable(net->user_ns, CAP_NET_RAW))
2817 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2818 sock->type != SOCK_PACKET)
2819 return -ESOCKTNOSUPPORT;
2821 sock->state = SS_UNCONNECTED;
2824 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2828 sock->ops = &packet_ops;
2829 if (sock->type == SOCK_PACKET)
2830 sock->ops = &packet_ops_spkt;
2832 sock_init_data(sock, sk);
2835 sk->sk_family = PF_PACKET;
2837 po->xmit = dev_queue_xmit;
2839 err = packet_alloc_pending(po);
2843 packet_cached_dev_reset(po);
2845 sk->sk_destruct = packet_sock_destruct;
2846 sk_refcnt_debug_inc(sk);
2849 * Attach a protocol block
2852 spin_lock_init(&po->bind_lock);
2853 mutex_init(&po->pg_vec_lock);
2854 po->prot_hook.func = packet_rcv;
2856 if (sock->type == SOCK_PACKET)
2857 po->prot_hook.func = packet_rcv_spkt;
2859 po->prot_hook.af_packet_priv = sk;
2862 po->prot_hook.type = proto;
2863 register_prot_hook(sk);
2866 mutex_lock(&net->packet.sklist_lock);
2867 sk_add_node_rcu(sk, &net->packet.sklist);
2868 mutex_unlock(&net->packet.sklist_lock);
2871 sock_prot_inuse_add(net, &packet_proto, 1);
2882 * Pull a packet from our receive queue and hand it to the user.
2883 * If necessary we block.
2886 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
2889 struct sock *sk = sock->sk;
2890 struct sk_buff *skb;
2892 int vnet_hdr_len = 0;
2893 unsigned int origlen = 0;
2896 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2900 /* What error should we return now? EUNATTACH? */
2901 if (pkt_sk(sk)->ifindex < 0)
2905 if (flags & MSG_ERRQUEUE) {
2906 err = sock_recv_errqueue(sk, msg, len,
2907 SOL_PACKET, PACKET_TX_TIMESTAMP);
2912 * Call the generic datagram receiver. This handles all sorts
2913 * of horrible races and re-entrancy so we can forget about it
2914 * in the protocol layers.
2916 * Now it will return ENETDOWN, if device have just gone down,
2917 * but then it will block.
2920 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2923 * An error occurred so return it. Because skb_recv_datagram()
2924 * handles the blocking we don't see and worry about blocking
2931 if (pkt_sk(sk)->has_vnet_hdr) {
2932 struct virtio_net_hdr vnet_hdr = { 0 };
2935 vnet_hdr_len = sizeof(vnet_hdr);
2936 if (len < vnet_hdr_len)
2939 len -= vnet_hdr_len;
2941 if (skb_is_gso(skb)) {
2942 struct skb_shared_info *sinfo = skb_shinfo(skb);
2944 /* This is a hint as to how much should be linear. */
2946 __cpu_to_virtio16(false, skb_headlen(skb));
2948 __cpu_to_virtio16(false, sinfo->gso_size);
2949 if (sinfo->gso_type & SKB_GSO_TCPV4)
2950 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2951 else if (sinfo->gso_type & SKB_GSO_TCPV6)
2952 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2953 else if (sinfo->gso_type & SKB_GSO_UDP)
2954 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2955 else if (sinfo->gso_type & SKB_GSO_FCOE)
2959 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2960 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2962 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2964 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2965 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2966 vnet_hdr.csum_start = __cpu_to_virtio16(false,
2967 skb_checksum_start_offset(skb));
2968 vnet_hdr.csum_offset = __cpu_to_virtio16(false,
2970 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2971 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2972 } /* else everything is zero */
2974 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
2979 /* You lose any data beyond the buffer you gave. If it worries
2980 * a user program they can ask the device for its MTU
2986 msg->msg_flags |= MSG_TRUNC;
2989 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2993 if (sock->type != SOCK_PACKET) {
2994 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2996 /* Original length was stored in sockaddr_ll fields */
2997 origlen = PACKET_SKB_CB(skb)->sa.origlen;
2998 sll->sll_family = AF_PACKET;
2999 sll->sll_protocol = skb->protocol;
3002 sock_recv_ts_and_drops(msg, sk, skb);
3004 if (msg->msg_name) {
3005 /* If the address length field is there to be filled
3006 * in, we fill it in now.
3008 if (sock->type == SOCK_PACKET) {
3009 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3010 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3012 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3014 msg->msg_namelen = sll->sll_halen +
3015 offsetof(struct sockaddr_ll, sll_addr);
3017 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3021 if (pkt_sk(sk)->auxdata) {
3022 struct tpacket_auxdata aux;
3024 aux.tp_status = TP_STATUS_USER;
3025 if (skb->ip_summed == CHECKSUM_PARTIAL)
3026 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3027 else if (skb->pkt_type != PACKET_OUTGOING &&
3028 (skb->ip_summed == CHECKSUM_COMPLETE ||
3029 skb_csum_unnecessary(skb)))
3030 aux.tp_status |= TP_STATUS_CSUM_VALID;
3032 aux.tp_len = origlen;
3033 aux.tp_snaplen = skb->len;
3035 aux.tp_net = skb_network_offset(skb);
3036 if (skb_vlan_tag_present(skb)) {
3037 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3038 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3039 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3041 aux.tp_vlan_tci = 0;
3042 aux.tp_vlan_tpid = 0;
3044 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3048 * Free or return the buffer as appropriate. Again this
3049 * hides all the races and re-entrancy issues from us.
3051 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3054 skb_free_datagram(sk, skb);
3059 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3060 int *uaddr_len, int peer)
3062 struct net_device *dev;
3063 struct sock *sk = sock->sk;
3068 uaddr->sa_family = AF_PACKET;
3069 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3071 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3073 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3075 *uaddr_len = sizeof(*uaddr);
3080 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3081 int *uaddr_len, int peer)
3083 struct net_device *dev;
3084 struct sock *sk = sock->sk;
3085 struct packet_sock *po = pkt_sk(sk);
3086 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3091 sll->sll_family = AF_PACKET;
3092 sll->sll_ifindex = po->ifindex;
3093 sll->sll_protocol = po->num;
3094 sll->sll_pkttype = 0;
3096 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3098 sll->sll_hatype = dev->type;
3099 sll->sll_halen = dev->addr_len;
3100 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3102 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3106 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3111 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3115 case PACKET_MR_MULTICAST:
3116 if (i->alen != dev->addr_len)
3119 return dev_mc_add(dev, i->addr);
3121 return dev_mc_del(dev, i->addr);
3123 case PACKET_MR_PROMISC:
3124 return dev_set_promiscuity(dev, what);
3125 case PACKET_MR_ALLMULTI:
3126 return dev_set_allmulti(dev, what);
3127 case PACKET_MR_UNICAST:
3128 if (i->alen != dev->addr_len)
3131 return dev_uc_add(dev, i->addr);
3133 return dev_uc_del(dev, i->addr);
3141 static void packet_dev_mclist_delete(struct net_device *dev,
3142 struct packet_mclist **mlp)
3144 struct packet_mclist *ml;
3146 while ((ml = *mlp) != NULL) {
3147 if (ml->ifindex == dev->ifindex) {
3148 packet_dev_mc(dev, ml, -1);
3156 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3158 struct packet_sock *po = pkt_sk(sk);
3159 struct packet_mclist *ml, *i;
3160 struct net_device *dev;
3166 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3171 if (mreq->mr_alen > dev->addr_len)
3175 i = kmalloc(sizeof(*i), GFP_KERNEL);
3180 for (ml = po->mclist; ml; ml = ml->next) {
3181 if (ml->ifindex == mreq->mr_ifindex &&
3182 ml->type == mreq->mr_type &&
3183 ml->alen == mreq->mr_alen &&
3184 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3186 /* Free the new element ... */
3192 i->type = mreq->mr_type;
3193 i->ifindex = mreq->mr_ifindex;
3194 i->alen = mreq->mr_alen;
3195 memcpy(i->addr, mreq->mr_address, i->alen);
3197 i->next = po->mclist;
3199 err = packet_dev_mc(dev, i, 1);
3201 po->mclist = i->next;
3210 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3212 struct packet_mclist *ml, **mlp;
3216 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3217 if (ml->ifindex == mreq->mr_ifindex &&
3218 ml->type == mreq->mr_type &&
3219 ml->alen == mreq->mr_alen &&
3220 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3221 if (--ml->count == 0) {
3222 struct net_device *dev;
3224 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3226 packet_dev_mc(dev, ml, -1);
3236 static void packet_flush_mclist(struct sock *sk)
3238 struct packet_sock *po = pkt_sk(sk);
3239 struct packet_mclist *ml;
3245 while ((ml = po->mclist) != NULL) {
3246 struct net_device *dev;
3248 po->mclist = ml->next;
3249 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3251 packet_dev_mc(dev, ml, -1);
3258 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3260 struct sock *sk = sock->sk;
3261 struct packet_sock *po = pkt_sk(sk);
3264 if (level != SOL_PACKET)
3265 return -ENOPROTOOPT;
3268 case PACKET_ADD_MEMBERSHIP:
3269 case PACKET_DROP_MEMBERSHIP:
3271 struct packet_mreq_max mreq;
3273 memset(&mreq, 0, sizeof(mreq));
3274 if (len < sizeof(struct packet_mreq))
3276 if (len > sizeof(mreq))
3278 if (copy_from_user(&mreq, optval, len))
3280 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3282 if (optname == PACKET_ADD_MEMBERSHIP)
3283 ret = packet_mc_add(sk, &mreq);
3285 ret = packet_mc_drop(sk, &mreq);
3289 case PACKET_RX_RING:
3290 case PACKET_TX_RING:
3292 union tpacket_req_u req_u;
3295 switch (po->tp_version) {
3298 len = sizeof(req_u.req);
3302 len = sizeof(req_u.req3);
3307 if (pkt_sk(sk)->has_vnet_hdr)
3309 if (copy_from_user(&req_u.req, optval, len))
3311 return packet_set_ring(sk, &req_u, 0,
3312 optname == PACKET_TX_RING);
3314 case PACKET_COPY_THRESH:
3318 if (optlen != sizeof(val))
3320 if (copy_from_user(&val, optval, sizeof(val)))
3323 pkt_sk(sk)->copy_thresh = val;
3326 case PACKET_VERSION:
3330 if (optlen != sizeof(val))
3332 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3334 if (copy_from_user(&val, optval, sizeof(val)))
3340 po->tp_version = val;
3346 case PACKET_RESERVE:
3350 if (optlen != sizeof(val))
3352 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3354 if (copy_from_user(&val, optval, sizeof(val)))
3356 po->tp_reserve = val;
3363 if (optlen != sizeof(val))
3365 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3367 if (copy_from_user(&val, optval, sizeof(val)))
3369 po->tp_loss = !!val;
3372 case PACKET_AUXDATA:
3376 if (optlen < sizeof(val))
3378 if (copy_from_user(&val, optval, sizeof(val)))
3381 po->auxdata = !!val;
3384 case PACKET_ORIGDEV:
3388 if (optlen < sizeof(val))
3390 if (copy_from_user(&val, optval, sizeof(val)))
3393 po->origdev = !!val;
3396 case PACKET_VNET_HDR:
3400 if (sock->type != SOCK_RAW)
3402 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3404 if (optlen < sizeof(val))
3406 if (copy_from_user(&val, optval, sizeof(val)))
3409 po->has_vnet_hdr = !!val;
3412 case PACKET_TIMESTAMP:
3416 if (optlen != sizeof(val))
3418 if (copy_from_user(&val, optval, sizeof(val)))
3421 po->tp_tstamp = val;
3428 if (optlen != sizeof(val))
3430 if (copy_from_user(&val, optval, sizeof(val)))
3433 return fanout_add(sk, val & 0xffff, val >> 16);
3435 case PACKET_TX_HAS_OFF:
3439 if (optlen != sizeof(val))
3441 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3443 if (copy_from_user(&val, optval, sizeof(val)))
3445 po->tp_tx_has_off = !!val;
3448 case PACKET_QDISC_BYPASS:
3452 if (optlen != sizeof(val))
3454 if (copy_from_user(&val, optval, sizeof(val)))
3457 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3461 return -ENOPROTOOPT;
3465 static int packet_getsockopt(struct socket *sock, int level, int optname,
3466 char __user *optval, int __user *optlen)
3469 int val, lv = sizeof(val);
3470 struct sock *sk = sock->sk;
3471 struct packet_sock *po = pkt_sk(sk);
3473 union tpacket_stats_u st;
3475 if (level != SOL_PACKET)
3476 return -ENOPROTOOPT;
3478 if (get_user(len, optlen))
3485 case PACKET_STATISTICS:
3486 spin_lock_bh(&sk->sk_receive_queue.lock);
3487 memcpy(&st, &po->stats, sizeof(st));
3488 memset(&po->stats, 0, sizeof(po->stats));
3489 spin_unlock_bh(&sk->sk_receive_queue.lock);
3491 if (po->tp_version == TPACKET_V3) {
3492 lv = sizeof(struct tpacket_stats_v3);
3493 st.stats3.tp_packets += st.stats3.tp_drops;
3496 lv = sizeof(struct tpacket_stats);
3497 st.stats1.tp_packets += st.stats1.tp_drops;
3502 case PACKET_AUXDATA:
3505 case PACKET_ORIGDEV:
3508 case PACKET_VNET_HDR:
3509 val = po->has_vnet_hdr;
3511 case PACKET_VERSION:
3512 val = po->tp_version;
3515 if (len > sizeof(int))
3517 if (copy_from_user(&val, optval, len))
3521 val = sizeof(struct tpacket_hdr);
3524 val = sizeof(struct tpacket2_hdr);
3527 val = sizeof(struct tpacket3_hdr);
3533 case PACKET_RESERVE:
3534 val = po->tp_reserve;
3539 case PACKET_TIMESTAMP:
3540 val = po->tp_tstamp;
3544 ((u32)po->fanout->id |
3545 ((u32)po->fanout->type << 16) |
3546 ((u32)po->fanout->flags << 24)) :
3549 case PACKET_TX_HAS_OFF:
3550 val = po->tp_tx_has_off;
3552 case PACKET_QDISC_BYPASS:
3553 val = packet_use_direct_xmit(po);
3556 return -ENOPROTOOPT;
3561 if (put_user(len, optlen))
3563 if (copy_to_user(optval, data, len))
3569 static int packet_notifier(struct notifier_block *this,
3570 unsigned long msg, void *ptr)
3573 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3574 struct net *net = dev_net(dev);
3577 sk_for_each_rcu(sk, &net->packet.sklist) {
3578 struct packet_sock *po = pkt_sk(sk);
3581 case NETDEV_UNREGISTER:
3583 packet_dev_mclist_delete(dev, &po->mclist);
3587 if (dev->ifindex == po->ifindex) {
3588 spin_lock(&po->bind_lock);
3590 __unregister_prot_hook(sk, false);
3591 sk->sk_err = ENETDOWN;
3592 if (!sock_flag(sk, SOCK_DEAD))
3593 sk->sk_error_report(sk);
3595 if (msg == NETDEV_UNREGISTER) {
3596 packet_cached_dev_reset(po);
3598 if (po->prot_hook.dev)
3599 dev_put(po->prot_hook.dev);
3600 po->prot_hook.dev = NULL;
3602 spin_unlock(&po->bind_lock);
3606 if (dev->ifindex == po->ifindex) {
3607 spin_lock(&po->bind_lock);
3609 register_prot_hook(sk);
3610 spin_unlock(&po->bind_lock);
3620 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3623 struct sock *sk = sock->sk;
3628 int amount = sk_wmem_alloc_get(sk);
3630 return put_user(amount, (int __user *)arg);
3634 struct sk_buff *skb;
3637 spin_lock_bh(&sk->sk_receive_queue.lock);
3638 skb = skb_peek(&sk->sk_receive_queue);
3641 spin_unlock_bh(&sk->sk_receive_queue.lock);
3642 return put_user(amount, (int __user *)arg);
3645 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3647 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3657 case SIOCGIFBRDADDR:
3658 case SIOCSIFBRDADDR:
3659 case SIOCGIFNETMASK:
3660 case SIOCSIFNETMASK:
3661 case SIOCGIFDSTADDR:
3662 case SIOCSIFDSTADDR:
3664 return inet_dgram_ops.ioctl(sock, cmd, arg);
3668 return -ENOIOCTLCMD;
3673 static unsigned int packet_poll(struct file *file, struct socket *sock,
3676 struct sock *sk = sock->sk;
3677 struct packet_sock *po = pkt_sk(sk);
3678 unsigned int mask = datagram_poll(file, sock, wait);
3680 spin_lock_bh(&sk->sk_receive_queue.lock);
3681 if (po->rx_ring.pg_vec) {
3682 if (!packet_previous_rx_frame(po, &po->rx_ring,
3684 mask |= POLLIN | POLLRDNORM;
3686 spin_unlock_bh(&sk->sk_receive_queue.lock);
3687 spin_lock_bh(&sk->sk_write_queue.lock);
3688 if (po->tx_ring.pg_vec) {
3689 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3690 mask |= POLLOUT | POLLWRNORM;
3692 spin_unlock_bh(&sk->sk_write_queue.lock);
3697 /* Dirty? Well, I still did not learn better way to account
3701 static void packet_mm_open(struct vm_area_struct *vma)
3703 struct file *file = vma->vm_file;
3704 struct socket *sock = file->private_data;
3705 struct sock *sk = sock->sk;
3708 atomic_inc(&pkt_sk(sk)->mapped);
3711 static void packet_mm_close(struct vm_area_struct *vma)
3713 struct file *file = vma->vm_file;
3714 struct socket *sock = file->private_data;
3715 struct sock *sk = sock->sk;
3718 atomic_dec(&pkt_sk(sk)->mapped);
3721 static const struct vm_operations_struct packet_mmap_ops = {
3722 .open = packet_mm_open,
3723 .close = packet_mm_close,
3726 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3731 for (i = 0; i < len; i++) {
3732 if (likely(pg_vec[i].buffer)) {
3733 if (is_vmalloc_addr(pg_vec[i].buffer))
3734 vfree(pg_vec[i].buffer);
3736 free_pages((unsigned long)pg_vec[i].buffer,
3738 pg_vec[i].buffer = NULL;
3744 static char *alloc_one_pg_vec_page(unsigned long order)
3747 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3748 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3750 buffer = (char *) __get_free_pages(gfp_flags, order);
3754 /* __get_free_pages failed, fall back to vmalloc */
3755 buffer = vzalloc((1 << order) * PAGE_SIZE);
3759 /* vmalloc failed, lets dig into swap here */
3760 gfp_flags &= ~__GFP_NORETRY;
3761 buffer = (char *) __get_free_pages(gfp_flags, order);
3765 /* complete and utter failure */
3769 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3771 unsigned int block_nr = req->tp_block_nr;
3775 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3776 if (unlikely(!pg_vec))
3779 for (i = 0; i < block_nr; i++) {
3780 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3781 if (unlikely(!pg_vec[i].buffer))
3782 goto out_free_pgvec;
3789 free_pg_vec(pg_vec, order, block_nr);
3794 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3795 int closing, int tx_ring)
3797 struct pgv *pg_vec = NULL;
3798 struct packet_sock *po = pkt_sk(sk);
3799 int was_running, order = 0;
3800 struct packet_ring_buffer *rb;
3801 struct sk_buff_head *rb_queue;
3804 /* Added to avoid minimal code churn */
3805 struct tpacket_req *req = &req_u->req;
3807 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3808 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3809 WARN(1, "Tx-ring is not supported.\n");
3813 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3814 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3818 if (atomic_read(&po->mapped))
3820 if (packet_read_pending(rb))
3824 if (req->tp_block_nr) {
3825 /* Sanity tests and some calculations */
3827 if (unlikely(rb->pg_vec))
3830 switch (po->tp_version) {
3832 po->tp_hdrlen = TPACKET_HDRLEN;
3835 po->tp_hdrlen = TPACKET2_HDRLEN;
3838 po->tp_hdrlen = TPACKET3_HDRLEN;
3843 if (unlikely((int)req->tp_block_size <= 0))
3845 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3847 if (po->tp_version >= TPACKET_V3 &&
3848 (int)(req->tp_block_size -
3849 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
3851 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3854 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3857 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3858 if (unlikely(rb->frames_per_block <= 0))
3860 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3865 order = get_order(req->tp_block_size);
3866 pg_vec = alloc_pg_vec(req, order);
3867 if (unlikely(!pg_vec))
3869 switch (po->tp_version) {
3871 /* Transmit path is not supported. We checked
3872 * it above but just being paranoid
3875 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3884 if (unlikely(req->tp_frame_nr))
3890 /* Detach socket from network */
3891 spin_lock(&po->bind_lock);
3892 was_running = po->running;
3896 __unregister_prot_hook(sk, false);
3898 spin_unlock(&po->bind_lock);
3903 mutex_lock(&po->pg_vec_lock);
3904 if (closing || atomic_read(&po->mapped) == 0) {
3906 spin_lock_bh(&rb_queue->lock);
3907 swap(rb->pg_vec, pg_vec);
3908 rb->frame_max = (req->tp_frame_nr - 1);
3910 rb->frame_size = req->tp_frame_size;
3911 spin_unlock_bh(&rb_queue->lock);
3913 swap(rb->pg_vec_order, order);
3914 swap(rb->pg_vec_len, req->tp_block_nr);
3916 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3917 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3918 tpacket_rcv : packet_rcv;
3919 skb_queue_purge(rb_queue);
3920 if (atomic_read(&po->mapped))
3921 pr_err("packet_mmap: vma is busy: %d\n",
3922 atomic_read(&po->mapped));
3924 mutex_unlock(&po->pg_vec_lock);
3926 spin_lock(&po->bind_lock);
3929 register_prot_hook(sk);
3931 spin_unlock(&po->bind_lock);
3932 if (closing && (po->tp_version > TPACKET_V2)) {
3933 /* Because we don't support block-based V3 on tx-ring */
3935 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3940 free_pg_vec(pg_vec, order, req->tp_block_nr);
3945 static int packet_mmap(struct file *file, struct socket *sock,
3946 struct vm_area_struct *vma)
3948 struct sock *sk = sock->sk;
3949 struct packet_sock *po = pkt_sk(sk);
3950 unsigned long size, expected_size;
3951 struct packet_ring_buffer *rb;
3952 unsigned long start;
3959 mutex_lock(&po->pg_vec_lock);
3962 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3964 expected_size += rb->pg_vec_len
3970 if (expected_size == 0)
3973 size = vma->vm_end - vma->vm_start;
3974 if (size != expected_size)
3977 start = vma->vm_start;
3978 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3979 if (rb->pg_vec == NULL)
3982 for (i = 0; i < rb->pg_vec_len; i++) {
3984 void *kaddr = rb->pg_vec[i].buffer;
3987 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3988 page = pgv_to_page(kaddr);
3989 err = vm_insert_page(vma, start, page);
3998 atomic_inc(&po->mapped);
3999 vma->vm_ops = &packet_mmap_ops;
4003 mutex_unlock(&po->pg_vec_lock);
4007 static const struct proto_ops packet_ops_spkt = {
4008 .family = PF_PACKET,
4009 .owner = THIS_MODULE,
4010 .release = packet_release,
4011 .bind = packet_bind_spkt,
4012 .connect = sock_no_connect,
4013 .socketpair = sock_no_socketpair,
4014 .accept = sock_no_accept,
4015 .getname = packet_getname_spkt,
4016 .poll = datagram_poll,
4017 .ioctl = packet_ioctl,
4018 .listen = sock_no_listen,
4019 .shutdown = sock_no_shutdown,
4020 .setsockopt = sock_no_setsockopt,
4021 .getsockopt = sock_no_getsockopt,
4022 .sendmsg = packet_sendmsg_spkt,
4023 .recvmsg = packet_recvmsg,
4024 .mmap = sock_no_mmap,
4025 .sendpage = sock_no_sendpage,
4028 static const struct proto_ops packet_ops = {
4029 .family = PF_PACKET,
4030 .owner = THIS_MODULE,
4031 .release = packet_release,
4032 .bind = packet_bind,
4033 .connect = sock_no_connect,
4034 .socketpair = sock_no_socketpair,
4035 .accept = sock_no_accept,
4036 .getname = packet_getname,
4037 .poll = packet_poll,
4038 .ioctl = packet_ioctl,
4039 .listen = sock_no_listen,
4040 .shutdown = sock_no_shutdown,
4041 .setsockopt = packet_setsockopt,
4042 .getsockopt = packet_getsockopt,
4043 .sendmsg = packet_sendmsg,
4044 .recvmsg = packet_recvmsg,
4045 .mmap = packet_mmap,
4046 .sendpage = sock_no_sendpage,
4049 static const struct net_proto_family packet_family_ops = {
4050 .family = PF_PACKET,
4051 .create = packet_create,
4052 .owner = THIS_MODULE,
4055 static struct notifier_block packet_netdev_notifier = {
4056 .notifier_call = packet_notifier,
4059 #ifdef CONFIG_PROC_FS
4061 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4064 struct net *net = seq_file_net(seq);
4067 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4070 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4072 struct net *net = seq_file_net(seq);
4073 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4076 static void packet_seq_stop(struct seq_file *seq, void *v)
4082 static int packet_seq_show(struct seq_file *seq, void *v)
4084 if (v == SEQ_START_TOKEN)
4085 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4087 struct sock *s = sk_entry(v);
4088 const struct packet_sock *po = pkt_sk(s);
4091 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4093 atomic_read(&s->sk_refcnt),
4098 atomic_read(&s->sk_rmem_alloc),
4099 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4106 static const struct seq_operations packet_seq_ops = {
4107 .start = packet_seq_start,
4108 .next = packet_seq_next,
4109 .stop = packet_seq_stop,
4110 .show = packet_seq_show,
4113 static int packet_seq_open(struct inode *inode, struct file *file)
4115 return seq_open_net(inode, file, &packet_seq_ops,
4116 sizeof(struct seq_net_private));
4119 static const struct file_operations packet_seq_fops = {
4120 .owner = THIS_MODULE,
4121 .open = packet_seq_open,
4123 .llseek = seq_lseek,
4124 .release = seq_release_net,
4129 static int __net_init packet_net_init(struct net *net)
4131 mutex_init(&net->packet.sklist_lock);
4132 INIT_HLIST_HEAD(&net->packet.sklist);
4134 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4140 static void __net_exit packet_net_exit(struct net *net)
4142 remove_proc_entry("packet", net->proc_net);
4145 static struct pernet_operations packet_net_ops = {
4146 .init = packet_net_init,
4147 .exit = packet_net_exit,
4151 static void __exit packet_exit(void)
4153 unregister_netdevice_notifier(&packet_netdev_notifier);
4154 unregister_pernet_subsys(&packet_net_ops);
4155 sock_unregister(PF_PACKET);
4156 proto_unregister(&packet_proto);
4159 static int __init packet_init(void)
4161 int rc = proto_register(&packet_proto, 0);
4166 sock_register(&packet_family_ops);
4167 register_pernet_subsys(&packet_net_ops);
4168 register_netdevice_notifier(&packet_netdev_notifier);
4173 module_init(packet_init);
4174 module_exit(packet_exit);
4175 MODULE_LICENSE("GPL");
4176 MODULE_ALIAS_NETPROTO(PF_PACKET);