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 {
220 struct sockaddr_pkt pkt;
222 /* Trick: alias skb original length with
223 * ll.sll_family and ll.protocol in order
226 unsigned int origlen;
227 struct sockaddr_ll ll;
232 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
234 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
235 #define GET_PBLOCK_DESC(x, bid) \
236 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
237 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
238 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
239 #define GET_NEXT_PRB_BLK_NUM(x) \
240 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
241 ((x)->kactive_blk_num+1) : 0)
243 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
244 static void __fanout_link(struct sock *sk, struct packet_sock *po);
246 static int packet_direct_xmit(struct sk_buff *skb)
248 struct net_device *dev = skb->dev;
249 netdev_features_t features;
250 struct netdev_queue *txq;
251 int ret = NETDEV_TX_BUSY;
253 if (unlikely(!netif_running(dev) ||
254 !netif_carrier_ok(dev)))
257 features = netif_skb_features(skb);
258 if (skb_needs_linearize(skb, features) &&
259 __skb_linearize(skb))
262 txq = skb_get_tx_queue(dev, skb);
266 HARD_TX_LOCK(dev, txq, smp_processor_id());
267 if (!netif_xmit_frozen_or_drv_stopped(txq))
268 ret = netdev_start_xmit(skb, dev, txq, false);
269 HARD_TX_UNLOCK(dev, txq);
273 if (!dev_xmit_complete(ret))
278 atomic_long_inc(&dev->tx_dropped);
280 return NET_XMIT_DROP;
283 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
285 struct net_device *dev;
288 dev = rcu_dereference(po->cached_dev);
296 static void packet_cached_dev_assign(struct packet_sock *po,
297 struct net_device *dev)
299 rcu_assign_pointer(po->cached_dev, dev);
302 static void packet_cached_dev_reset(struct packet_sock *po)
304 RCU_INIT_POINTER(po->cached_dev, NULL);
307 static bool packet_use_direct_xmit(const struct packet_sock *po)
309 return po->xmit == packet_direct_xmit;
312 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
314 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
317 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
319 const struct net_device_ops *ops = dev->netdev_ops;
322 if (ops->ndo_select_queue) {
323 queue_index = ops->ndo_select_queue(dev, skb, NULL,
324 __packet_pick_tx_queue);
325 queue_index = netdev_cap_txqueue(dev, queue_index);
327 queue_index = __packet_pick_tx_queue(dev, skb);
330 skb_set_queue_mapping(skb, queue_index);
333 /* register_prot_hook must be invoked with the po->bind_lock held,
334 * or from a context in which asynchronous accesses to the packet
335 * socket is not possible (packet_create()).
337 static void register_prot_hook(struct sock *sk)
339 struct packet_sock *po = pkt_sk(sk);
343 __fanout_link(sk, po);
345 dev_add_pack(&po->prot_hook);
352 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
353 * held. If the sync parameter is true, we will temporarily drop
354 * the po->bind_lock and do a synchronize_net to make sure no
355 * asynchronous packet processing paths still refer to the elements
356 * of po->prot_hook. If the sync parameter is false, it is the
357 * callers responsibility to take care of this.
359 static void __unregister_prot_hook(struct sock *sk, bool sync)
361 struct packet_sock *po = pkt_sk(sk);
366 __fanout_unlink(sk, po);
368 __dev_remove_pack(&po->prot_hook);
373 spin_unlock(&po->bind_lock);
375 spin_lock(&po->bind_lock);
379 static void unregister_prot_hook(struct sock *sk, bool sync)
381 struct packet_sock *po = pkt_sk(sk);
384 __unregister_prot_hook(sk, sync);
387 static inline struct page * __pure pgv_to_page(void *addr)
389 if (is_vmalloc_addr(addr))
390 return vmalloc_to_page(addr);
391 return virt_to_page(addr);
394 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
396 union tpacket_uhdr h;
399 switch (po->tp_version) {
401 h.h1->tp_status = status;
402 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
405 h.h2->tp_status = status;
406 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
410 WARN(1, "TPACKET version not supported.\n");
417 static int __packet_get_status(struct packet_sock *po, void *frame)
419 union tpacket_uhdr h;
424 switch (po->tp_version) {
426 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
427 return h.h1->tp_status;
429 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
430 return h.h2->tp_status;
433 WARN(1, "TPACKET version not supported.\n");
439 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
442 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
445 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
446 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
447 return TP_STATUS_TS_RAW_HARDWARE;
449 if (ktime_to_timespec_cond(skb->tstamp, ts))
450 return TP_STATUS_TS_SOFTWARE;
455 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
458 union tpacket_uhdr h;
462 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
466 switch (po->tp_version) {
468 h.h1->tp_sec = ts.tv_sec;
469 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
472 h.h2->tp_sec = ts.tv_sec;
473 h.h2->tp_nsec = ts.tv_nsec;
477 WARN(1, "TPACKET version not supported.\n");
481 /* one flush is safe, as both fields always lie on the same cacheline */
482 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
488 static void *packet_lookup_frame(struct packet_sock *po,
489 struct packet_ring_buffer *rb,
490 unsigned int position,
493 unsigned int pg_vec_pos, frame_offset;
494 union tpacket_uhdr h;
496 pg_vec_pos = position / rb->frames_per_block;
497 frame_offset = position % rb->frames_per_block;
499 h.raw = rb->pg_vec[pg_vec_pos].buffer +
500 (frame_offset * rb->frame_size);
502 if (status != __packet_get_status(po, h.raw))
508 static void *packet_current_frame(struct packet_sock *po,
509 struct packet_ring_buffer *rb,
512 return packet_lookup_frame(po, rb, rb->head, status);
515 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
517 del_timer_sync(&pkc->retire_blk_timer);
520 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
522 struct sk_buff_head *rb_queue)
524 struct tpacket_kbdq_core *pkc;
526 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
527 GET_PBDQC_FROM_RB(&po->rx_ring);
529 spin_lock_bh(&rb_queue->lock);
530 pkc->delete_blk_timer = 1;
531 spin_unlock_bh(&rb_queue->lock);
533 prb_del_retire_blk_timer(pkc);
536 static void prb_init_blk_timer(struct packet_sock *po,
537 struct tpacket_kbdq_core *pkc,
538 void (*func) (unsigned long))
540 init_timer(&pkc->retire_blk_timer);
541 pkc->retire_blk_timer.data = (long)po;
542 pkc->retire_blk_timer.function = func;
543 pkc->retire_blk_timer.expires = jiffies;
546 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
548 struct tpacket_kbdq_core *pkc;
553 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
554 GET_PBDQC_FROM_RB(&po->rx_ring);
555 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
558 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
559 int blk_size_in_bytes)
561 struct net_device *dev;
562 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
563 struct ethtool_cmd ecmd;
568 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
569 if (unlikely(!dev)) {
571 return DEFAULT_PRB_RETIRE_TOV;
573 err = __ethtool_get_settings(dev, &ecmd);
574 speed = ethtool_cmd_speed(&ecmd);
578 * If the link speed is so slow you don't really
579 * need to worry about perf anyways
581 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
582 return DEFAULT_PRB_RETIRE_TOV;
589 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
601 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
602 union tpacket_req_u *req_u)
604 p1->feature_req_word = req_u->req3.tp_feature_req_word;
607 static void init_prb_bdqc(struct packet_sock *po,
608 struct packet_ring_buffer *rb,
610 union tpacket_req_u *req_u, int tx_ring)
612 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
613 struct tpacket_block_desc *pbd;
615 memset(p1, 0x0, sizeof(*p1));
617 p1->knxt_seq_num = 1;
619 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
620 p1->pkblk_start = pg_vec[0].buffer;
621 p1->kblk_size = req_u->req3.tp_block_size;
622 p1->knum_blocks = req_u->req3.tp_block_nr;
623 p1->hdrlen = po->tp_hdrlen;
624 p1->version = po->tp_version;
625 p1->last_kactive_blk_num = 0;
626 po->stats.stats3.tp_freeze_q_cnt = 0;
627 if (req_u->req3.tp_retire_blk_tov)
628 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
630 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
631 req_u->req3.tp_block_size);
632 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
633 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
635 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
636 prb_init_ft_ops(p1, req_u);
637 prb_setup_retire_blk_timer(po, tx_ring);
638 prb_open_block(p1, pbd);
641 /* Do NOT update the last_blk_num first.
642 * Assumes sk_buff_head lock is held.
644 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
646 mod_timer(&pkc->retire_blk_timer,
647 jiffies + pkc->tov_in_jiffies);
648 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
653 * 1) We refresh the timer only when we open a block.
654 * By doing this we don't waste cycles refreshing the timer
655 * on packet-by-packet basis.
657 * With a 1MB block-size, on a 1Gbps line, it will take
658 * i) ~8 ms to fill a block + ii) memcpy etc.
659 * In this cut we are not accounting for the memcpy time.
661 * So, if the user sets the 'tmo' to 10ms then the timer
662 * will never fire while the block is still getting filled
663 * (which is what we want). However, the user could choose
664 * to close a block early and that's fine.
666 * But when the timer does fire, we check whether or not to refresh it.
667 * Since the tmo granularity is in msecs, it is not too expensive
668 * to refresh the timer, lets say every '8' msecs.
669 * Either the user can set the 'tmo' or we can derive it based on
670 * a) line-speed and b) block-size.
671 * prb_calc_retire_blk_tmo() calculates the tmo.
674 static void prb_retire_rx_blk_timer_expired(unsigned long data)
676 struct packet_sock *po = (struct packet_sock *)data;
677 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
679 struct tpacket_block_desc *pbd;
681 spin_lock(&po->sk.sk_receive_queue.lock);
683 frozen = prb_queue_frozen(pkc);
684 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
686 if (unlikely(pkc->delete_blk_timer))
689 /* We only need to plug the race when the block is partially filled.
691 * lock(); increment BLOCK_NUM_PKTS; unlock()
692 * copy_bits() is in progress ...
693 * timer fires on other cpu:
694 * we can't retire the current block because copy_bits
698 if (BLOCK_NUM_PKTS(pbd)) {
699 while (atomic_read(&pkc->blk_fill_in_prog)) {
700 /* Waiting for skb_copy_bits to finish... */
705 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
707 if (!BLOCK_NUM_PKTS(pbd)) {
708 /* An empty block. Just refresh the timer. */
711 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
712 if (!prb_dispatch_next_block(pkc, po))
717 /* Case 1. Queue was frozen because user-space was
720 if (prb_curr_blk_in_use(pkc, pbd)) {
722 * Ok, user-space is still behind.
723 * So just refresh the timer.
727 /* Case 2. queue was frozen,user-space caught up,
728 * now the link went idle && the timer fired.
729 * We don't have a block to close.So we open this
730 * block and restart the timer.
731 * opening a block thaws the queue,restarts timer
732 * Thawing/timer-refresh is a side effect.
734 prb_open_block(pkc, pbd);
741 _prb_refresh_rx_retire_blk_timer(pkc);
744 spin_unlock(&po->sk.sk_receive_queue.lock);
747 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
748 struct tpacket_block_desc *pbd1, __u32 status)
750 /* Flush everything minus the block header */
752 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
757 /* Skip the block header(we know header WILL fit in 4K) */
760 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
761 for (; start < end; start += PAGE_SIZE)
762 flush_dcache_page(pgv_to_page(start));
767 /* Now update the block status. */
769 BLOCK_STATUS(pbd1) = status;
771 /* Flush the block header */
773 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
775 flush_dcache_page(pgv_to_page(start));
785 * 2) Increment active_blk_num
787 * Note:We DONT refresh the timer on purpose.
788 * Because almost always the next block will be opened.
790 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
791 struct tpacket_block_desc *pbd1,
792 struct packet_sock *po, unsigned int stat)
794 __u32 status = TP_STATUS_USER | stat;
796 struct tpacket3_hdr *last_pkt;
797 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
798 struct sock *sk = &po->sk;
800 if (po->stats.stats3.tp_drops)
801 status |= TP_STATUS_LOSING;
803 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
804 last_pkt->tp_next_offset = 0;
806 /* Get the ts of the last pkt */
807 if (BLOCK_NUM_PKTS(pbd1)) {
808 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
809 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
811 /* Ok, we tmo'd - so get the current time.
813 * It shouldn't really happen as we don't close empty
814 * blocks. See prb_retire_rx_blk_timer_expired().
818 h1->ts_last_pkt.ts_sec = ts.tv_sec;
819 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
824 /* Flush the block */
825 prb_flush_block(pkc1, pbd1, status);
827 sk->sk_data_ready(sk);
829 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
832 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
834 pkc->reset_pending_on_curr_blk = 0;
838 * Side effect of opening a block:
840 * 1) prb_queue is thawed.
841 * 2) retire_blk_timer is refreshed.
844 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
845 struct tpacket_block_desc *pbd1)
848 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
852 /* We could have just memset this but we will lose the
853 * flexibility of making the priv area sticky
856 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
857 BLOCK_NUM_PKTS(pbd1) = 0;
858 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
862 h1->ts_first_pkt.ts_sec = ts.tv_sec;
863 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
865 pkc1->pkblk_start = (char *)pbd1;
866 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
868 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
869 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
871 pbd1->version = pkc1->version;
872 pkc1->prev = pkc1->nxt_offset;
873 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
875 prb_thaw_queue(pkc1);
876 _prb_refresh_rx_retire_blk_timer(pkc1);
882 * Queue freeze logic:
883 * 1) Assume tp_block_nr = 8 blocks.
884 * 2) At time 't0', user opens Rx ring.
885 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
886 * 4) user-space is either sleeping or processing block '0'.
887 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
888 * it will close block-7,loop around and try to fill block '0'.
890 * __packet_lookup_frame_in_block
891 * prb_retire_current_block()
892 * prb_dispatch_next_block()
893 * |->(BLOCK_STATUS == USER) evaluates to true
894 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
895 * 6) Now there are two cases:
896 * 6.1) Link goes idle right after the queue is frozen.
897 * But remember, the last open_block() refreshed the timer.
898 * When this timer expires,it will refresh itself so that we can
899 * re-open block-0 in near future.
900 * 6.2) Link is busy and keeps on receiving packets. This is a simple
901 * case and __packet_lookup_frame_in_block will check if block-0
902 * is free and can now be re-used.
904 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
905 struct packet_sock *po)
907 pkc->reset_pending_on_curr_blk = 1;
908 po->stats.stats3.tp_freeze_q_cnt++;
911 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
914 * If the next block is free then we will dispatch it
915 * and return a good offset.
916 * Else, we will freeze the queue.
917 * So, caller must check the return value.
919 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
920 struct packet_sock *po)
922 struct tpacket_block_desc *pbd;
926 /* 1. Get current block num */
927 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
929 /* 2. If this block is currently in_use then freeze the queue */
930 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
931 prb_freeze_queue(pkc, po);
937 * open this block and return the offset where the first packet
938 * needs to get stored.
940 prb_open_block(pkc, pbd);
941 return (void *)pkc->nxt_offset;
944 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
945 struct packet_sock *po, unsigned int status)
947 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
949 /* retire/close the current block */
950 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
952 * Plug the case where copy_bits() is in progress on
953 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
954 * have space to copy the pkt in the current block and
955 * called prb_retire_current_block()
957 * We don't need to worry about the TMO case because
958 * the timer-handler already handled this case.
960 if (!(status & TP_STATUS_BLK_TMO)) {
961 while (atomic_read(&pkc->blk_fill_in_prog)) {
962 /* Waiting for skb_copy_bits to finish... */
966 prb_close_block(pkc, pbd, po, status);
971 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
972 struct tpacket_block_desc *pbd)
974 return TP_STATUS_USER & BLOCK_STATUS(pbd);
977 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
979 return pkc->reset_pending_on_curr_blk;
982 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
984 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
985 atomic_dec(&pkc->blk_fill_in_prog);
988 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
989 struct tpacket3_hdr *ppd)
991 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
994 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
995 struct tpacket3_hdr *ppd)
997 ppd->hv1.tp_rxhash = 0;
1000 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
1001 struct tpacket3_hdr *ppd)
1003 if (skb_vlan_tag_present(pkc->skb)) {
1004 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1005 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1006 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1008 ppd->hv1.tp_vlan_tci = 0;
1009 ppd->hv1.tp_vlan_tpid = 0;
1010 ppd->tp_status = TP_STATUS_AVAILABLE;
1014 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1015 struct tpacket3_hdr *ppd)
1017 ppd->hv1.tp_padding = 0;
1018 prb_fill_vlan_info(pkc, ppd);
1020 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1021 prb_fill_rxhash(pkc, ppd);
1023 prb_clear_rxhash(pkc, ppd);
1026 static void prb_fill_curr_block(char *curr,
1027 struct tpacket_kbdq_core *pkc,
1028 struct tpacket_block_desc *pbd,
1031 struct tpacket3_hdr *ppd;
1033 ppd = (struct tpacket3_hdr *)curr;
1034 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1036 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1037 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1038 BLOCK_NUM_PKTS(pbd) += 1;
1039 atomic_inc(&pkc->blk_fill_in_prog);
1040 prb_run_all_ft_ops(pkc, ppd);
1043 /* Assumes caller has the sk->rx_queue.lock */
1044 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1045 struct sk_buff *skb,
1050 struct tpacket_kbdq_core *pkc;
1051 struct tpacket_block_desc *pbd;
1054 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1055 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1057 /* Queue is frozen when user space is lagging behind */
1058 if (prb_queue_frozen(pkc)) {
1060 * Check if that last block which caused the queue to freeze,
1061 * is still in_use by user-space.
1063 if (prb_curr_blk_in_use(pkc, pbd)) {
1064 /* Can't record this packet */
1068 * Ok, the block was released by user-space.
1069 * Now let's open that block.
1070 * opening a block also thaws the queue.
1071 * Thawing is a side effect.
1073 prb_open_block(pkc, pbd);
1078 curr = pkc->nxt_offset;
1080 end = (char *)pbd + pkc->kblk_size;
1082 /* first try the current block */
1083 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1084 prb_fill_curr_block(curr, pkc, pbd, len);
1085 return (void *)curr;
1088 /* Ok, close the current block */
1089 prb_retire_current_block(pkc, po, 0);
1091 /* Now, try to dispatch the next block */
1092 curr = (char *)prb_dispatch_next_block(pkc, po);
1094 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1095 prb_fill_curr_block(curr, pkc, pbd, len);
1096 return (void *)curr;
1100 * No free blocks are available.user_space hasn't caught up yet.
1101 * Queue was just frozen and now this packet will get dropped.
1106 static void *packet_current_rx_frame(struct packet_sock *po,
1107 struct sk_buff *skb,
1108 int status, unsigned int len)
1111 switch (po->tp_version) {
1114 curr = packet_lookup_frame(po, &po->rx_ring,
1115 po->rx_ring.head, status);
1118 return __packet_lookup_frame_in_block(po, skb, status, len);
1120 WARN(1, "TPACKET version not supported\n");
1126 static void *prb_lookup_block(struct packet_sock *po,
1127 struct packet_ring_buffer *rb,
1131 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1132 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1134 if (status != BLOCK_STATUS(pbd))
1139 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1142 if (rb->prb_bdqc.kactive_blk_num)
1143 prev = rb->prb_bdqc.kactive_blk_num-1;
1145 prev = rb->prb_bdqc.knum_blocks-1;
1149 /* Assumes caller has held the rx_queue.lock */
1150 static void *__prb_previous_block(struct packet_sock *po,
1151 struct packet_ring_buffer *rb,
1154 unsigned int previous = prb_previous_blk_num(rb);
1155 return prb_lookup_block(po, rb, previous, status);
1158 static void *packet_previous_rx_frame(struct packet_sock *po,
1159 struct packet_ring_buffer *rb,
1162 if (po->tp_version <= TPACKET_V2)
1163 return packet_previous_frame(po, rb, status);
1165 return __prb_previous_block(po, rb, status);
1168 static void packet_increment_rx_head(struct packet_sock *po,
1169 struct packet_ring_buffer *rb)
1171 switch (po->tp_version) {
1174 return packet_increment_head(rb);
1177 WARN(1, "TPACKET version not supported.\n");
1183 static void *packet_previous_frame(struct packet_sock *po,
1184 struct packet_ring_buffer *rb,
1187 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1188 return packet_lookup_frame(po, rb, previous, status);
1191 static void packet_increment_head(struct packet_ring_buffer *buff)
1193 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1196 static void packet_inc_pending(struct packet_ring_buffer *rb)
1198 this_cpu_inc(*rb->pending_refcnt);
1201 static void packet_dec_pending(struct packet_ring_buffer *rb)
1203 this_cpu_dec(*rb->pending_refcnt);
1206 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1208 unsigned int refcnt = 0;
1211 /* We don't use pending refcount in rx_ring. */
1212 if (rb->pending_refcnt == NULL)
1215 for_each_possible_cpu(cpu)
1216 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1221 static int packet_alloc_pending(struct packet_sock *po)
1223 po->rx_ring.pending_refcnt = NULL;
1225 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1226 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1232 static void packet_free_pending(struct packet_sock *po)
1234 free_percpu(po->tx_ring.pending_refcnt);
1237 #define ROOM_POW_OFF 2
1238 #define ROOM_NONE 0x0
1239 #define ROOM_LOW 0x1
1240 #define ROOM_NORMAL 0x2
1242 static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1246 len = po->rx_ring.frame_max + 1;
1247 idx = po->rx_ring.head;
1249 idx += len >> pow_off;
1252 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1255 static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1259 len = po->rx_ring.prb_bdqc.knum_blocks;
1260 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1262 idx += len >> pow_off;
1265 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1268 static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1270 struct sock *sk = &po->sk;
1271 int ret = ROOM_NONE;
1273 if (po->prot_hook.func != tpacket_rcv) {
1274 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1275 - (skb ? skb->truesize : 0);
1276 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1284 if (po->tp_version == TPACKET_V3) {
1285 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1287 else if (__tpacket_v3_has_room(po, 0))
1290 if (__tpacket_has_room(po, ROOM_POW_OFF))
1292 else if (__tpacket_has_room(po, 0))
1299 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1304 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1305 ret = __packet_rcv_has_room(po, skb);
1306 has_room = ret == ROOM_NORMAL;
1307 if (po->pressure == has_room)
1308 po->pressure = !has_room;
1309 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1314 static void packet_sock_destruct(struct sock *sk)
1316 skb_queue_purge(&sk->sk_error_queue);
1318 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1319 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1321 if (!sock_flag(sk, SOCK_DEAD)) {
1322 pr_err("Attempt to release alive packet socket: %p\n", sk);
1326 sk_refcnt_debug_dec(sk);
1329 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1331 int x = atomic_read(&f->rr_cur) + 1;
1339 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1344 rxhash = skb_get_hash(skb);
1345 for (i = 0; i < ROLLOVER_HLEN; i++)
1346 if (po->rollover->history[i] == rxhash)
1349 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1350 return count > (ROLLOVER_HLEN >> 1);
1353 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1354 struct sk_buff *skb,
1357 return reciprocal_scale(skb_get_hash(skb), num);
1360 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1361 struct sk_buff *skb,
1366 cur = atomic_read(&f->rr_cur);
1367 while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1368 fanout_rr_next(f, num))) != cur)
1373 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1374 struct sk_buff *skb,
1377 return smp_processor_id() % num;
1380 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1381 struct sk_buff *skb,
1384 return prandom_u32_max(num);
1387 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1388 struct sk_buff *skb,
1389 unsigned int idx, bool try_self,
1392 struct packet_sock *po, *po_next, *po_skip = NULL;
1393 unsigned int i, j, room = ROOM_NONE;
1395 po = pkt_sk(f->arr[idx]);
1398 room = packet_rcv_has_room(po, skb);
1399 if (room == ROOM_NORMAL ||
1400 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1405 i = j = min_t(int, po->rollover->sock, num - 1);
1407 po_next = pkt_sk(f->arr[i]);
1408 if (po_next != po_skip && !po_next->pressure &&
1409 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1411 po->rollover->sock = i;
1412 atomic_long_inc(&po->rollover->num);
1413 if (room == ROOM_LOW)
1414 atomic_long_inc(&po->rollover->num_huge);
1422 atomic_long_inc(&po->rollover->num_failed);
1426 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1427 struct sk_buff *skb,
1430 return skb_get_queue_mapping(skb) % num;
1433 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1435 return f->flags & (flag >> 8);
1438 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1439 struct packet_type *pt, struct net_device *orig_dev)
1441 struct packet_fanout *f = pt->af_packet_priv;
1442 unsigned int num = f->num_members;
1443 struct packet_sock *po;
1446 if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1452 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1453 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1458 case PACKET_FANOUT_HASH:
1460 idx = fanout_demux_hash(f, skb, num);
1462 case PACKET_FANOUT_LB:
1463 idx = fanout_demux_lb(f, skb, num);
1465 case PACKET_FANOUT_CPU:
1466 idx = fanout_demux_cpu(f, skb, num);
1468 case PACKET_FANOUT_RND:
1469 idx = fanout_demux_rnd(f, skb, num);
1471 case PACKET_FANOUT_QM:
1472 idx = fanout_demux_qm(f, skb, num);
1474 case PACKET_FANOUT_ROLLOVER:
1475 idx = fanout_demux_rollover(f, skb, 0, false, num);
1479 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1480 idx = fanout_demux_rollover(f, skb, idx, true, num);
1482 po = pkt_sk(f->arr[idx]);
1483 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1486 DEFINE_MUTEX(fanout_mutex);
1487 EXPORT_SYMBOL_GPL(fanout_mutex);
1488 static LIST_HEAD(fanout_list);
1490 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1492 struct packet_fanout *f = po->fanout;
1494 spin_lock(&f->lock);
1495 f->arr[f->num_members] = sk;
1498 spin_unlock(&f->lock);
1501 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1503 struct packet_fanout *f = po->fanout;
1506 spin_lock(&f->lock);
1507 for (i = 0; i < f->num_members; i++) {
1508 if (f->arr[i] == sk)
1511 BUG_ON(i >= f->num_members);
1512 f->arr[i] = f->arr[f->num_members - 1];
1514 spin_unlock(&f->lock);
1517 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1519 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1525 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1527 struct packet_sock *po = pkt_sk(sk);
1528 struct packet_fanout *f, *match;
1529 u8 type = type_flags & 0xff;
1530 u8 flags = type_flags >> 8;
1534 case PACKET_FANOUT_ROLLOVER:
1535 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1537 case PACKET_FANOUT_HASH:
1538 case PACKET_FANOUT_LB:
1539 case PACKET_FANOUT_CPU:
1540 case PACKET_FANOUT_RND:
1541 case PACKET_FANOUT_QM:
1553 if (type == PACKET_FANOUT_ROLLOVER ||
1554 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1555 po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
1558 atomic_long_set(&po->rollover->num, 0);
1559 atomic_long_set(&po->rollover->num_huge, 0);
1560 atomic_long_set(&po->rollover->num_failed, 0);
1563 mutex_lock(&fanout_mutex);
1565 list_for_each_entry(f, &fanout_list, list) {
1567 read_pnet(&f->net) == sock_net(sk)) {
1573 if (match && match->flags != flags)
1577 match = kzalloc(sizeof(*match), GFP_KERNEL);
1580 write_pnet(&match->net, sock_net(sk));
1583 match->flags = flags;
1584 atomic_set(&match->rr_cur, 0);
1585 INIT_LIST_HEAD(&match->list);
1586 spin_lock_init(&match->lock);
1587 atomic_set(&match->sk_ref, 0);
1588 match->prot_hook.type = po->prot_hook.type;
1589 match->prot_hook.dev = po->prot_hook.dev;
1590 match->prot_hook.func = packet_rcv_fanout;
1591 match->prot_hook.af_packet_priv = match;
1592 match->prot_hook.id_match = match_fanout_group;
1593 dev_add_pack(&match->prot_hook);
1594 list_add(&match->list, &fanout_list);
1597 if (match->type == type &&
1598 match->prot_hook.type == po->prot_hook.type &&
1599 match->prot_hook.dev == po->prot_hook.dev) {
1601 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1602 __dev_remove_pack(&po->prot_hook);
1604 atomic_inc(&match->sk_ref);
1605 __fanout_link(sk, po);
1610 mutex_unlock(&fanout_mutex);
1612 kfree(po->rollover);
1613 po->rollover = NULL;
1618 static void fanout_release(struct sock *sk)
1620 struct packet_sock *po = pkt_sk(sk);
1621 struct packet_fanout *f;
1627 mutex_lock(&fanout_mutex);
1630 if (atomic_dec_and_test(&f->sk_ref)) {
1632 dev_remove_pack(&f->prot_hook);
1635 mutex_unlock(&fanout_mutex);
1637 kfree(po->rollover);
1640 static const struct proto_ops packet_ops;
1642 static const struct proto_ops packet_ops_spkt;
1644 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1645 struct packet_type *pt, struct net_device *orig_dev)
1648 struct sockaddr_pkt *spkt;
1651 * When we registered the protocol we saved the socket in the data
1652 * field for just this event.
1655 sk = pt->af_packet_priv;
1658 * Yank back the headers [hope the device set this
1659 * right or kerboom...]
1661 * Incoming packets have ll header pulled,
1664 * For outgoing ones skb->data == skb_mac_header(skb)
1665 * so that this procedure is noop.
1668 if (skb->pkt_type == PACKET_LOOPBACK)
1671 if (!net_eq(dev_net(dev), sock_net(sk)))
1674 skb = skb_share_check(skb, GFP_ATOMIC);
1678 /* drop any routing info */
1681 /* drop conntrack reference */
1684 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1686 skb_push(skb, skb->data - skb_mac_header(skb));
1689 * The SOCK_PACKET socket receives _all_ frames.
1692 spkt->spkt_family = dev->type;
1693 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1694 spkt->spkt_protocol = skb->protocol;
1697 * Charge the memory to the socket. This is done specifically
1698 * to prevent sockets using all the memory up.
1701 if (sock_queue_rcv_skb(sk, skb) == 0)
1712 * Output a raw packet to a device layer. This bypasses all the other
1713 * protocol layers and you must therefore supply it with a complete frame
1716 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1719 struct sock *sk = sock->sk;
1720 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1721 struct sk_buff *skb = NULL;
1722 struct net_device *dev;
1728 * Get and verify the address.
1732 if (msg->msg_namelen < sizeof(struct sockaddr))
1734 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1735 proto = saddr->spkt_protocol;
1737 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1740 * Find the device first to size check it
1743 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1746 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1752 if (!(dev->flags & IFF_UP))
1756 * You may not queue a frame bigger than the mtu. This is the lowest level
1757 * raw protocol and you must do your own fragmentation at this level.
1760 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1761 if (!netif_supports_nofcs(dev)) {
1762 err = -EPROTONOSUPPORT;
1765 extra_len = 4; /* We're doing our own CRC */
1769 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1773 size_t reserved = LL_RESERVED_SPACE(dev);
1774 int tlen = dev->needed_tailroom;
1775 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1778 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1781 /* FIXME: Save some space for broken drivers that write a hard
1782 * header at transmission time by themselves. PPP is the notable
1783 * one here. This should really be fixed at the driver level.
1785 skb_reserve(skb, reserved);
1786 skb_reset_network_header(skb);
1788 /* Try to align data part correctly */
1793 skb_reset_network_header(skb);
1795 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1801 if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1802 /* Earlier code assumed this would be a VLAN pkt,
1803 * double-check this now that we have the actual
1806 struct ethhdr *ehdr;
1807 skb_reset_mac_header(skb);
1808 ehdr = eth_hdr(skb);
1809 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1815 skb->protocol = proto;
1817 skb->priority = sk->sk_priority;
1818 skb->mark = sk->sk_mark;
1820 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1822 if (unlikely(extra_len == 4))
1825 skb_probe_transport_header(skb, 0);
1827 dev_queue_xmit(skb);
1838 static unsigned int run_filter(const struct sk_buff *skb,
1839 const struct sock *sk,
1842 struct sk_filter *filter;
1845 filter = rcu_dereference(sk->sk_filter);
1847 res = SK_RUN_FILTER(filter, skb);
1854 * This function makes lazy skb cloning in hope that most of packets
1855 * are discarded by BPF.
1857 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1858 * and skb->cb are mangled. It works because (and until) packets
1859 * falling here are owned by current CPU. Output packets are cloned
1860 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1861 * sequencially, so that if we return skb to original state on exit,
1862 * we will not harm anyone.
1865 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1866 struct packet_type *pt, struct net_device *orig_dev)
1869 struct sockaddr_ll *sll;
1870 struct packet_sock *po;
1871 u8 *skb_head = skb->data;
1872 int skb_len = skb->len;
1873 unsigned int snaplen, res;
1875 if (skb->pkt_type == PACKET_LOOPBACK)
1878 sk = pt->af_packet_priv;
1881 if (!net_eq(dev_net(dev), sock_net(sk)))
1886 if (dev->header_ops) {
1887 /* The device has an explicit notion of ll header,
1888 * exported to higher levels.
1890 * Otherwise, the device hides details of its frame
1891 * structure, so that corresponding packet head is
1892 * never delivered to user.
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));
1904 res = run_filter(skb, sk, snaplen);
1906 goto drop_n_restore;
1910 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1913 if (skb_shared(skb)) {
1914 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1918 if (skb_head != skb->data) {
1919 skb->data = skb_head;
1926 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
1928 sll = &PACKET_SKB_CB(skb)->sa.ll;
1929 sll->sll_hatype = dev->type;
1930 sll->sll_pkttype = skb->pkt_type;
1931 if (unlikely(po->origdev))
1932 sll->sll_ifindex = orig_dev->ifindex;
1934 sll->sll_ifindex = dev->ifindex;
1936 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1938 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
1939 * Use their space for storing the original skb length.
1941 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
1943 if (pskb_trim(skb, snaplen))
1946 skb_set_owner_r(skb, sk);
1950 /* drop conntrack reference */
1953 spin_lock(&sk->sk_receive_queue.lock);
1954 po->stats.stats1.tp_packets++;
1955 sock_skb_set_dropcount(sk, skb);
1956 __skb_queue_tail(&sk->sk_receive_queue, skb);
1957 spin_unlock(&sk->sk_receive_queue.lock);
1958 sk->sk_data_ready(sk);
1962 spin_lock(&sk->sk_receive_queue.lock);
1963 po->stats.stats1.tp_drops++;
1964 atomic_inc(&sk->sk_drops);
1965 spin_unlock(&sk->sk_receive_queue.lock);
1968 if (skb_head != skb->data && skb_shared(skb)) {
1969 skb->data = skb_head;
1977 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1978 struct packet_type *pt, struct net_device *orig_dev)
1981 struct packet_sock *po;
1982 struct sockaddr_ll *sll;
1983 union tpacket_uhdr h;
1984 u8 *skb_head = skb->data;
1985 int skb_len = skb->len;
1986 unsigned int snaplen, res;
1987 unsigned long status = TP_STATUS_USER;
1988 unsigned short macoff, netoff, hdrlen;
1989 struct sk_buff *copy_skb = NULL;
1993 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
1994 * We may add members to them until current aligned size without forcing
1995 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
1997 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
1998 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2000 if (skb->pkt_type == PACKET_LOOPBACK)
2003 sk = pt->af_packet_priv;
2006 if (!net_eq(dev_net(dev), sock_net(sk)))
2009 if (dev->header_ops) {
2010 if (sk->sk_type != SOCK_DGRAM)
2011 skb_push(skb, skb->data - skb_mac_header(skb));
2012 else if (skb->pkt_type == PACKET_OUTGOING) {
2013 /* Special case: outgoing packets have ll header at head */
2014 skb_pull(skb, skb_network_offset(skb));
2020 res = run_filter(skb, sk, snaplen);
2022 goto drop_n_restore;
2024 if (skb->ip_summed == CHECKSUM_PARTIAL)
2025 status |= TP_STATUS_CSUMNOTREADY;
2026 else if (skb->pkt_type != PACKET_OUTGOING &&
2027 (skb->ip_summed == CHECKSUM_COMPLETE ||
2028 skb_csum_unnecessary(skb)))
2029 status |= TP_STATUS_CSUM_VALID;
2034 if (sk->sk_type == SOCK_DGRAM) {
2035 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2038 unsigned int maclen = skb_network_offset(skb);
2039 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2040 (maclen < 16 ? 16 : maclen)) +
2042 macoff = netoff - maclen;
2044 if (po->tp_version <= TPACKET_V2) {
2045 if (macoff + snaplen > po->rx_ring.frame_size) {
2046 if (po->copy_thresh &&
2047 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2048 if (skb_shared(skb)) {
2049 copy_skb = skb_clone(skb, GFP_ATOMIC);
2051 copy_skb = skb_get(skb);
2052 skb_head = skb->data;
2055 skb_set_owner_r(copy_skb, sk);
2057 snaplen = po->rx_ring.frame_size - macoff;
2058 if ((int)snaplen < 0)
2061 } else if (unlikely(macoff + snaplen >
2062 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2065 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2066 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2067 snaplen, nval, macoff);
2069 if (unlikely((int)snaplen < 0)) {
2071 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2074 spin_lock(&sk->sk_receive_queue.lock);
2075 h.raw = packet_current_rx_frame(po, skb,
2076 TP_STATUS_KERNEL, (macoff+snaplen));
2079 if (po->tp_version <= TPACKET_V2) {
2080 packet_increment_rx_head(po, &po->rx_ring);
2082 * LOSING will be reported till you read the stats,
2083 * because it's COR - Clear On Read.
2084 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2087 if (po->stats.stats1.tp_drops)
2088 status |= TP_STATUS_LOSING;
2090 po->stats.stats1.tp_packets++;
2092 status |= TP_STATUS_COPY;
2093 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2095 spin_unlock(&sk->sk_receive_queue.lock);
2097 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2099 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2100 getnstimeofday(&ts);
2102 status |= ts_status;
2104 switch (po->tp_version) {
2106 h.h1->tp_len = skb->len;
2107 h.h1->tp_snaplen = snaplen;
2108 h.h1->tp_mac = macoff;
2109 h.h1->tp_net = netoff;
2110 h.h1->tp_sec = ts.tv_sec;
2111 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2112 hdrlen = sizeof(*h.h1);
2115 h.h2->tp_len = skb->len;
2116 h.h2->tp_snaplen = snaplen;
2117 h.h2->tp_mac = macoff;
2118 h.h2->tp_net = netoff;
2119 h.h2->tp_sec = ts.tv_sec;
2120 h.h2->tp_nsec = ts.tv_nsec;
2121 if (skb_vlan_tag_present(skb)) {
2122 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2123 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2124 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2126 h.h2->tp_vlan_tci = 0;
2127 h.h2->tp_vlan_tpid = 0;
2129 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2130 hdrlen = sizeof(*h.h2);
2133 /* tp_nxt_offset,vlan are already populated above.
2134 * So DONT clear those fields here
2136 h.h3->tp_status |= status;
2137 h.h3->tp_len = skb->len;
2138 h.h3->tp_snaplen = snaplen;
2139 h.h3->tp_mac = macoff;
2140 h.h3->tp_net = netoff;
2141 h.h3->tp_sec = ts.tv_sec;
2142 h.h3->tp_nsec = ts.tv_nsec;
2143 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2144 hdrlen = sizeof(*h.h3);
2150 sll = h.raw + TPACKET_ALIGN(hdrlen);
2151 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2152 sll->sll_family = AF_PACKET;
2153 sll->sll_hatype = dev->type;
2154 sll->sll_protocol = skb->protocol;
2155 sll->sll_pkttype = skb->pkt_type;
2156 if (unlikely(po->origdev))
2157 sll->sll_ifindex = orig_dev->ifindex;
2159 sll->sll_ifindex = dev->ifindex;
2163 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2164 if (po->tp_version <= TPACKET_V2) {
2167 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2170 for (start = h.raw; start < end; start += PAGE_SIZE)
2171 flush_dcache_page(pgv_to_page(start));
2176 if (po->tp_version <= TPACKET_V2) {
2177 __packet_set_status(po, h.raw, status);
2178 sk->sk_data_ready(sk);
2180 prb_clear_blk_fill_status(&po->rx_ring);
2184 if (skb_head != skb->data && skb_shared(skb)) {
2185 skb->data = skb_head;
2193 po->stats.stats1.tp_drops++;
2194 spin_unlock(&sk->sk_receive_queue.lock);
2196 sk->sk_data_ready(sk);
2197 kfree_skb(copy_skb);
2198 goto drop_n_restore;
2201 static void tpacket_destruct_skb(struct sk_buff *skb)
2203 struct packet_sock *po = pkt_sk(skb->sk);
2205 if (likely(po->tx_ring.pg_vec)) {
2209 ph = skb_shinfo(skb)->destructor_arg;
2210 packet_dec_pending(&po->tx_ring);
2212 ts = __packet_set_timestamp(po, ph, skb);
2213 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2219 static bool ll_header_truncated(const struct net_device *dev, int len)
2221 /* net device doesn't like empty head */
2222 if (unlikely(len <= dev->hard_header_len)) {
2223 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n",
2224 current->comm, len, dev->hard_header_len);
2231 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2232 void *frame, struct net_device *dev, int size_max,
2233 __be16 proto, unsigned char *addr, int hlen)
2235 union tpacket_uhdr ph;
2236 int to_write, offset, len, tp_len, nr_frags, len_max;
2237 struct socket *sock = po->sk.sk_socket;
2244 skb->protocol = proto;
2246 skb->priority = po->sk.sk_priority;
2247 skb->mark = po->sk.sk_mark;
2248 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2249 skb_shinfo(skb)->destructor_arg = ph.raw;
2251 switch (po->tp_version) {
2253 tp_len = ph.h2->tp_len;
2256 tp_len = ph.h1->tp_len;
2259 if (unlikely(tp_len > size_max)) {
2260 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2264 skb_reserve(skb, hlen);
2265 skb_reset_network_header(skb);
2267 if (!packet_use_direct_xmit(po))
2268 skb_probe_transport_header(skb, 0);
2269 if (unlikely(po->tp_tx_has_off)) {
2270 int off_min, off_max, off;
2271 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2272 off_max = po->tx_ring.frame_size - tp_len;
2273 if (sock->type == SOCK_DGRAM) {
2274 switch (po->tp_version) {
2276 off = ph.h2->tp_net;
2279 off = ph.h1->tp_net;
2283 switch (po->tp_version) {
2285 off = ph.h2->tp_mac;
2288 off = ph.h1->tp_mac;
2292 if (unlikely((off < off_min) || (off_max < off)))
2294 data = ph.raw + off;
2296 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2300 if (sock->type == SOCK_DGRAM) {
2301 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2303 if (unlikely(err < 0))
2305 } else if (dev->hard_header_len) {
2306 if (ll_header_truncated(dev, tp_len))
2309 skb_push(skb, dev->hard_header_len);
2310 err = skb_store_bits(skb, 0, data,
2311 dev->hard_header_len);
2315 data += dev->hard_header_len;
2316 to_write -= dev->hard_header_len;
2319 offset = offset_in_page(data);
2320 len_max = PAGE_SIZE - offset;
2321 len = ((to_write > len_max) ? len_max : to_write);
2323 skb->data_len = to_write;
2324 skb->len += to_write;
2325 skb->truesize += to_write;
2326 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2328 while (likely(to_write)) {
2329 nr_frags = skb_shinfo(skb)->nr_frags;
2331 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2332 pr_err("Packet exceed the number of skb frags(%lu)\n",
2337 page = pgv_to_page(data);
2339 flush_dcache_page(page);
2341 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2344 len_max = PAGE_SIZE;
2345 len = ((to_write > len_max) ? len_max : to_write);
2351 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2353 struct sk_buff *skb;
2354 struct net_device *dev;
2356 int err, reserve = 0;
2358 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2359 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2360 int tp_len, size_max;
2361 unsigned char *addr;
2363 int status = TP_STATUS_AVAILABLE;
2366 mutex_lock(&po->pg_vec_lock);
2368 if (likely(saddr == NULL)) {
2369 dev = packet_cached_dev_get(po);
2374 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2376 if (msg->msg_namelen < (saddr->sll_halen
2377 + offsetof(struct sockaddr_ll,
2380 proto = saddr->sll_protocol;
2381 addr = saddr->sll_addr;
2382 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2386 if (unlikely(dev == NULL))
2389 if (unlikely(!(dev->flags & IFF_UP)))
2392 reserve = dev->hard_header_len + VLAN_HLEN;
2393 size_max = po->tx_ring.frame_size
2394 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2396 if (size_max > dev->mtu + reserve)
2397 size_max = dev->mtu + reserve;
2400 ph = packet_current_frame(po, &po->tx_ring,
2401 TP_STATUS_SEND_REQUEST);
2402 if (unlikely(ph == NULL)) {
2403 if (need_wait && need_resched())
2408 status = TP_STATUS_SEND_REQUEST;
2409 hlen = LL_RESERVED_SPACE(dev);
2410 tlen = dev->needed_tailroom;
2411 skb = sock_alloc_send_skb(&po->sk,
2412 hlen + tlen + sizeof(struct sockaddr_ll),
2415 if (unlikely(skb == NULL)) {
2416 /* we assume the socket was initially writeable ... */
2417 if (likely(len_sum > 0))
2421 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2423 if (tp_len > dev->mtu + dev->hard_header_len) {
2424 struct ethhdr *ehdr;
2425 /* Earlier code assumed this would be a VLAN pkt,
2426 * double-check this now that we have the actual
2430 skb_reset_mac_header(skb);
2431 ehdr = eth_hdr(skb);
2432 if (ehdr->h_proto != htons(ETH_P_8021Q))
2435 if (unlikely(tp_len < 0)) {
2437 __packet_set_status(po, ph,
2438 TP_STATUS_AVAILABLE);
2439 packet_increment_head(&po->tx_ring);
2443 status = TP_STATUS_WRONG_FORMAT;
2449 packet_pick_tx_queue(dev, skb);
2451 skb->destructor = tpacket_destruct_skb;
2452 __packet_set_status(po, ph, TP_STATUS_SENDING);
2453 packet_inc_pending(&po->tx_ring);
2455 status = TP_STATUS_SEND_REQUEST;
2456 err = po->xmit(skb);
2457 if (unlikely(err > 0)) {
2458 err = net_xmit_errno(err);
2459 if (err && __packet_get_status(po, ph) ==
2460 TP_STATUS_AVAILABLE) {
2461 /* skb was destructed already */
2466 * skb was dropped but not destructed yet;
2467 * let's treat it like congestion or err < 0
2471 packet_increment_head(&po->tx_ring);
2473 } while (likely((ph != NULL) ||
2474 /* Note: packet_read_pending() might be slow if we have
2475 * to call it as it's per_cpu variable, but in fast-path
2476 * we already short-circuit the loop with the first
2477 * condition, and luckily don't have to go that path
2480 (need_wait && packet_read_pending(&po->tx_ring))));
2486 __packet_set_status(po, ph, status);
2491 mutex_unlock(&po->pg_vec_lock);
2495 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2496 size_t reserve, size_t len,
2497 size_t linear, int noblock,
2500 struct sk_buff *skb;
2502 /* Under a page? Don't bother with paged skb. */
2503 if (prepad + len < PAGE_SIZE || !linear)
2506 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2511 skb_reserve(skb, reserve);
2512 skb_put(skb, linear);
2513 skb->data_len = len - linear;
2514 skb->len += len - linear;
2519 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2521 struct sock *sk = sock->sk;
2522 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2523 struct sk_buff *skb;
2524 struct net_device *dev;
2526 unsigned char *addr;
2527 int err, reserve = 0;
2528 struct virtio_net_hdr vnet_hdr = { 0 };
2531 struct packet_sock *po = pkt_sk(sk);
2532 unsigned short gso_type = 0;
2538 * Get and verify the address.
2541 if (likely(saddr == NULL)) {
2542 dev = packet_cached_dev_get(po);
2547 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2549 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2551 proto = saddr->sll_protocol;
2552 addr = saddr->sll_addr;
2553 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2557 if (unlikely(dev == NULL))
2560 if (unlikely(!(dev->flags & IFF_UP)))
2563 if (sock->type == SOCK_RAW)
2564 reserve = dev->hard_header_len;
2565 if (po->has_vnet_hdr) {
2566 vnet_hdr_len = sizeof(vnet_hdr);
2569 if (len < vnet_hdr_len)
2572 len -= vnet_hdr_len;
2575 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter);
2576 if (n != vnet_hdr_len)
2579 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2580 (__virtio16_to_cpu(false, vnet_hdr.csum_start) +
2581 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 >
2582 __virtio16_to_cpu(false, vnet_hdr.hdr_len)))
2583 vnet_hdr.hdr_len = __cpu_to_virtio16(false,
2584 __virtio16_to_cpu(false, vnet_hdr.csum_start) +
2585 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2);
2588 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len)
2591 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2592 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2593 case VIRTIO_NET_HDR_GSO_TCPV4:
2594 gso_type = SKB_GSO_TCPV4;
2596 case VIRTIO_NET_HDR_GSO_TCPV6:
2597 gso_type = SKB_GSO_TCPV6;
2599 case VIRTIO_NET_HDR_GSO_UDP:
2600 gso_type = SKB_GSO_UDP;
2606 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2607 gso_type |= SKB_GSO_TCP_ECN;
2609 if (vnet_hdr.gso_size == 0)
2615 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2616 if (!netif_supports_nofcs(dev)) {
2617 err = -EPROTONOSUPPORT;
2620 extra_len = 4; /* We're doing our own CRC */
2624 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2628 hlen = LL_RESERVED_SPACE(dev);
2629 tlen = dev->needed_tailroom;
2630 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2631 __virtio16_to_cpu(false, vnet_hdr.hdr_len),
2632 msg->msg_flags & MSG_DONTWAIT, &err);
2636 skb_set_network_header(skb, reserve);
2639 if (sock->type == SOCK_DGRAM) {
2640 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2641 if (unlikely(offset < 0))
2644 if (ll_header_truncated(dev, len))
2648 /* Returns -EFAULT on error */
2649 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2653 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2655 if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2656 /* Earlier code assumed this would be a VLAN pkt,
2657 * double-check this now that we have the actual
2660 struct ethhdr *ehdr;
2661 skb_reset_mac_header(skb);
2662 ehdr = eth_hdr(skb);
2663 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2669 skb->protocol = proto;
2671 skb->priority = sk->sk_priority;
2672 skb->mark = sk->sk_mark;
2674 packet_pick_tx_queue(dev, skb);
2676 if (po->has_vnet_hdr) {
2677 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2678 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start);
2679 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset);
2680 if (!skb_partial_csum_set(skb, s, o)) {
2686 skb_shinfo(skb)->gso_size =
2687 __virtio16_to_cpu(false, vnet_hdr.gso_size);
2688 skb_shinfo(skb)->gso_type = gso_type;
2690 /* Header must be checked, and gso_segs computed. */
2691 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2692 skb_shinfo(skb)->gso_segs = 0;
2694 len += vnet_hdr_len;
2697 if (!packet_use_direct_xmit(po))
2698 skb_probe_transport_header(skb, reserve);
2699 if (unlikely(extra_len == 4))
2702 err = po->xmit(skb);
2703 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2719 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2721 struct sock *sk = sock->sk;
2722 struct packet_sock *po = pkt_sk(sk);
2724 if (po->tx_ring.pg_vec)
2725 return tpacket_snd(po, msg);
2727 return packet_snd(sock, msg, len);
2731 * Close a PACKET socket. This is fairly simple. We immediately go
2732 * to 'closed' state and remove our protocol entry in the device list.
2735 static int packet_release(struct socket *sock)
2737 struct sock *sk = sock->sk;
2738 struct packet_sock *po;
2740 union tpacket_req_u req_u;
2748 mutex_lock(&net->packet.sklist_lock);
2749 sk_del_node_init_rcu(sk);
2750 mutex_unlock(&net->packet.sklist_lock);
2753 sock_prot_inuse_add(net, sk->sk_prot, -1);
2756 spin_lock(&po->bind_lock);
2757 unregister_prot_hook(sk, false);
2758 packet_cached_dev_reset(po);
2760 if (po->prot_hook.dev) {
2761 dev_put(po->prot_hook.dev);
2762 po->prot_hook.dev = NULL;
2764 spin_unlock(&po->bind_lock);
2766 packet_flush_mclist(sk);
2768 if (po->rx_ring.pg_vec) {
2769 memset(&req_u, 0, sizeof(req_u));
2770 packet_set_ring(sk, &req_u, 1, 0);
2773 if (po->tx_ring.pg_vec) {
2774 memset(&req_u, 0, sizeof(req_u));
2775 packet_set_ring(sk, &req_u, 1, 1);
2782 * Now the socket is dead. No more input will appear.
2789 skb_queue_purge(&sk->sk_receive_queue);
2790 packet_free_pending(po);
2791 sk_refcnt_debug_release(sk);
2798 * Attach a packet hook.
2801 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2803 struct packet_sock *po = pkt_sk(sk);
2804 const struct net_device *dev_curr;
2816 spin_lock(&po->bind_lock);
2818 proto_curr = po->prot_hook.type;
2819 dev_curr = po->prot_hook.dev;
2821 need_rehook = proto_curr != proto || dev_curr != dev;
2824 unregister_prot_hook(sk, true);
2827 po->prot_hook.type = proto;
2829 if (po->prot_hook.dev)
2830 dev_put(po->prot_hook.dev);
2832 po->prot_hook.dev = dev;
2834 po->ifindex = dev ? dev->ifindex : 0;
2835 packet_cached_dev_assign(po, dev);
2838 if (proto == 0 || !need_rehook)
2841 if (!dev || (dev->flags & IFF_UP)) {
2842 register_prot_hook(sk);
2844 sk->sk_err = ENETDOWN;
2845 if (!sock_flag(sk, SOCK_DEAD))
2846 sk->sk_error_report(sk);
2850 spin_unlock(&po->bind_lock);
2856 * Bind a packet socket to a device
2859 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2862 struct sock *sk = sock->sk;
2864 struct net_device *dev;
2871 if (addr_len != sizeof(struct sockaddr))
2873 strlcpy(name, uaddr->sa_data, sizeof(name));
2875 dev = dev_get_by_name(sock_net(sk), name);
2877 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2881 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2883 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2884 struct sock *sk = sock->sk;
2885 struct net_device *dev = NULL;
2893 if (addr_len < sizeof(struct sockaddr_ll))
2895 if (sll->sll_family != AF_PACKET)
2898 if (sll->sll_ifindex) {
2900 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2904 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2910 static struct proto packet_proto = {
2912 .owner = THIS_MODULE,
2913 .obj_size = sizeof(struct packet_sock),
2917 * Create a packet of type SOCK_PACKET.
2920 static int packet_create(struct net *net, struct socket *sock, int protocol,
2924 struct packet_sock *po;
2925 __be16 proto = (__force __be16)protocol; /* weird, but documented */
2928 if (!ns_capable(net->user_ns, CAP_NET_RAW))
2930 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2931 sock->type != SOCK_PACKET)
2932 return -ESOCKTNOSUPPORT;
2934 sock->state = SS_UNCONNECTED;
2937 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
2941 sock->ops = &packet_ops;
2942 if (sock->type == SOCK_PACKET)
2943 sock->ops = &packet_ops_spkt;
2945 sock_init_data(sock, sk);
2948 sk->sk_family = PF_PACKET;
2950 po->xmit = dev_queue_xmit;
2952 err = packet_alloc_pending(po);
2956 packet_cached_dev_reset(po);
2958 sk->sk_destruct = packet_sock_destruct;
2959 sk_refcnt_debug_inc(sk);
2962 * Attach a protocol block
2965 spin_lock_init(&po->bind_lock);
2966 mutex_init(&po->pg_vec_lock);
2967 po->rollover = NULL;
2968 po->prot_hook.func = packet_rcv;
2970 if (sock->type == SOCK_PACKET)
2971 po->prot_hook.func = packet_rcv_spkt;
2973 po->prot_hook.af_packet_priv = sk;
2976 po->prot_hook.type = proto;
2977 register_prot_hook(sk);
2980 mutex_lock(&net->packet.sklist_lock);
2981 sk_add_node_rcu(sk, &net->packet.sklist);
2982 mutex_unlock(&net->packet.sklist_lock);
2985 sock_prot_inuse_add(net, &packet_proto, 1);
2996 * Pull a packet from our receive queue and hand it to the user.
2997 * If necessary we block.
3000 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3003 struct sock *sk = sock->sk;
3004 struct sk_buff *skb;
3006 int vnet_hdr_len = 0;
3007 unsigned int origlen = 0;
3010 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3014 /* What error should we return now? EUNATTACH? */
3015 if (pkt_sk(sk)->ifindex < 0)
3019 if (flags & MSG_ERRQUEUE) {
3020 err = sock_recv_errqueue(sk, msg, len,
3021 SOL_PACKET, PACKET_TX_TIMESTAMP);
3026 * Call the generic datagram receiver. This handles all sorts
3027 * of horrible races and re-entrancy so we can forget about it
3028 * in the protocol layers.
3030 * Now it will return ENETDOWN, if device have just gone down,
3031 * but then it will block.
3034 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3037 * An error occurred so return it. Because skb_recv_datagram()
3038 * handles the blocking we don't see and worry about blocking
3045 if (pkt_sk(sk)->pressure)
3046 packet_rcv_has_room(pkt_sk(sk), NULL);
3048 if (pkt_sk(sk)->has_vnet_hdr) {
3049 struct virtio_net_hdr vnet_hdr = { 0 };
3052 vnet_hdr_len = sizeof(vnet_hdr);
3053 if (len < vnet_hdr_len)
3056 len -= vnet_hdr_len;
3058 if (skb_is_gso(skb)) {
3059 struct skb_shared_info *sinfo = skb_shinfo(skb);
3061 /* This is a hint as to how much should be linear. */
3063 __cpu_to_virtio16(false, skb_headlen(skb));
3065 __cpu_to_virtio16(false, sinfo->gso_size);
3066 if (sinfo->gso_type & SKB_GSO_TCPV4)
3067 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
3068 else if (sinfo->gso_type & SKB_GSO_TCPV6)
3069 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
3070 else if (sinfo->gso_type & SKB_GSO_UDP)
3071 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
3072 else if (sinfo->gso_type & SKB_GSO_FCOE)
3076 if (sinfo->gso_type & SKB_GSO_TCP_ECN)
3077 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
3079 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
3081 if (skb->ip_summed == CHECKSUM_PARTIAL) {
3082 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
3083 vnet_hdr.csum_start = __cpu_to_virtio16(false,
3084 skb_checksum_start_offset(skb));
3085 vnet_hdr.csum_offset = __cpu_to_virtio16(false,
3087 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
3088 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
3089 } /* else everything is zero */
3091 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
3096 /* You lose any data beyond the buffer you gave. If it worries
3097 * a user program they can ask the device for its MTU
3103 msg->msg_flags |= MSG_TRUNC;
3106 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3110 if (sock->type != SOCK_PACKET) {
3111 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3113 /* Original length was stored in sockaddr_ll fields */
3114 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3115 sll->sll_family = AF_PACKET;
3116 sll->sll_protocol = skb->protocol;
3119 sock_recv_ts_and_drops(msg, sk, skb);
3121 if (msg->msg_name) {
3122 /* If the address length field is there to be filled
3123 * in, we fill it in now.
3125 if (sock->type == SOCK_PACKET) {
3126 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3127 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3129 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3131 msg->msg_namelen = sll->sll_halen +
3132 offsetof(struct sockaddr_ll, sll_addr);
3134 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3138 if (pkt_sk(sk)->auxdata) {
3139 struct tpacket_auxdata aux;
3141 aux.tp_status = TP_STATUS_USER;
3142 if (skb->ip_summed == CHECKSUM_PARTIAL)
3143 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3144 else if (skb->pkt_type != PACKET_OUTGOING &&
3145 (skb->ip_summed == CHECKSUM_COMPLETE ||
3146 skb_csum_unnecessary(skb)))
3147 aux.tp_status |= TP_STATUS_CSUM_VALID;
3149 aux.tp_len = origlen;
3150 aux.tp_snaplen = skb->len;
3152 aux.tp_net = skb_network_offset(skb);
3153 if (skb_vlan_tag_present(skb)) {
3154 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3155 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3156 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3158 aux.tp_vlan_tci = 0;
3159 aux.tp_vlan_tpid = 0;
3161 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3165 * Free or return the buffer as appropriate. Again this
3166 * hides all the races and re-entrancy issues from us.
3168 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3171 skb_free_datagram(sk, skb);
3176 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3177 int *uaddr_len, int peer)
3179 struct net_device *dev;
3180 struct sock *sk = sock->sk;
3185 uaddr->sa_family = AF_PACKET;
3186 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3188 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3190 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3192 *uaddr_len = sizeof(*uaddr);
3197 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3198 int *uaddr_len, int peer)
3200 struct net_device *dev;
3201 struct sock *sk = sock->sk;
3202 struct packet_sock *po = pkt_sk(sk);
3203 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3208 sll->sll_family = AF_PACKET;
3209 sll->sll_ifindex = po->ifindex;
3210 sll->sll_protocol = po->num;
3211 sll->sll_pkttype = 0;
3213 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3215 sll->sll_hatype = dev->type;
3216 sll->sll_halen = dev->addr_len;
3217 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3219 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3223 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3228 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3232 case PACKET_MR_MULTICAST:
3233 if (i->alen != dev->addr_len)
3236 return dev_mc_add(dev, i->addr);
3238 return dev_mc_del(dev, i->addr);
3240 case PACKET_MR_PROMISC:
3241 return dev_set_promiscuity(dev, what);
3242 case PACKET_MR_ALLMULTI:
3243 return dev_set_allmulti(dev, what);
3244 case PACKET_MR_UNICAST:
3245 if (i->alen != dev->addr_len)
3248 return dev_uc_add(dev, i->addr);
3250 return dev_uc_del(dev, i->addr);
3258 static void packet_dev_mclist_delete(struct net_device *dev,
3259 struct packet_mclist **mlp)
3261 struct packet_mclist *ml;
3263 while ((ml = *mlp) != NULL) {
3264 if (ml->ifindex == dev->ifindex) {
3265 packet_dev_mc(dev, ml, -1);
3273 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3275 struct packet_sock *po = pkt_sk(sk);
3276 struct packet_mclist *ml, *i;
3277 struct net_device *dev;
3283 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3288 if (mreq->mr_alen > dev->addr_len)
3292 i = kmalloc(sizeof(*i), GFP_KERNEL);
3297 for (ml = po->mclist; ml; ml = ml->next) {
3298 if (ml->ifindex == mreq->mr_ifindex &&
3299 ml->type == mreq->mr_type &&
3300 ml->alen == mreq->mr_alen &&
3301 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3303 /* Free the new element ... */
3309 i->type = mreq->mr_type;
3310 i->ifindex = mreq->mr_ifindex;
3311 i->alen = mreq->mr_alen;
3312 memcpy(i->addr, mreq->mr_address, i->alen);
3314 i->next = po->mclist;
3316 err = packet_dev_mc(dev, i, 1);
3318 po->mclist = i->next;
3327 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3329 struct packet_mclist *ml, **mlp;
3333 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3334 if (ml->ifindex == mreq->mr_ifindex &&
3335 ml->type == mreq->mr_type &&
3336 ml->alen == mreq->mr_alen &&
3337 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3338 if (--ml->count == 0) {
3339 struct net_device *dev;
3341 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3343 packet_dev_mc(dev, ml, -1);
3353 static void packet_flush_mclist(struct sock *sk)
3355 struct packet_sock *po = pkt_sk(sk);
3356 struct packet_mclist *ml;
3362 while ((ml = po->mclist) != NULL) {
3363 struct net_device *dev;
3365 po->mclist = ml->next;
3366 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3368 packet_dev_mc(dev, ml, -1);
3375 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3377 struct sock *sk = sock->sk;
3378 struct packet_sock *po = pkt_sk(sk);
3381 if (level != SOL_PACKET)
3382 return -ENOPROTOOPT;
3385 case PACKET_ADD_MEMBERSHIP:
3386 case PACKET_DROP_MEMBERSHIP:
3388 struct packet_mreq_max mreq;
3390 memset(&mreq, 0, sizeof(mreq));
3391 if (len < sizeof(struct packet_mreq))
3393 if (len > sizeof(mreq))
3395 if (copy_from_user(&mreq, optval, len))
3397 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3399 if (optname == PACKET_ADD_MEMBERSHIP)
3400 ret = packet_mc_add(sk, &mreq);
3402 ret = packet_mc_drop(sk, &mreq);
3406 case PACKET_RX_RING:
3407 case PACKET_TX_RING:
3409 union tpacket_req_u req_u;
3412 switch (po->tp_version) {
3415 len = sizeof(req_u.req);
3419 len = sizeof(req_u.req3);
3424 if (pkt_sk(sk)->has_vnet_hdr)
3426 if (copy_from_user(&req_u.req, optval, len))
3428 return packet_set_ring(sk, &req_u, 0,
3429 optname == PACKET_TX_RING);
3431 case PACKET_COPY_THRESH:
3435 if (optlen != sizeof(val))
3437 if (copy_from_user(&val, optval, sizeof(val)))
3440 pkt_sk(sk)->copy_thresh = val;
3443 case PACKET_VERSION:
3447 if (optlen != sizeof(val))
3449 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3451 if (copy_from_user(&val, optval, sizeof(val)))
3457 po->tp_version = val;
3463 case PACKET_RESERVE:
3467 if (optlen != sizeof(val))
3469 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3471 if (copy_from_user(&val, optval, sizeof(val)))
3473 po->tp_reserve = val;
3480 if (optlen != sizeof(val))
3482 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3484 if (copy_from_user(&val, optval, sizeof(val)))
3486 po->tp_loss = !!val;
3489 case PACKET_AUXDATA:
3493 if (optlen < sizeof(val))
3495 if (copy_from_user(&val, optval, sizeof(val)))
3498 po->auxdata = !!val;
3501 case PACKET_ORIGDEV:
3505 if (optlen < sizeof(val))
3507 if (copy_from_user(&val, optval, sizeof(val)))
3510 po->origdev = !!val;
3513 case PACKET_VNET_HDR:
3517 if (sock->type != SOCK_RAW)
3519 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3521 if (optlen < sizeof(val))
3523 if (copy_from_user(&val, optval, sizeof(val)))
3526 po->has_vnet_hdr = !!val;
3529 case PACKET_TIMESTAMP:
3533 if (optlen != sizeof(val))
3535 if (copy_from_user(&val, optval, sizeof(val)))
3538 po->tp_tstamp = val;
3545 if (optlen != sizeof(val))
3547 if (copy_from_user(&val, optval, sizeof(val)))
3550 return fanout_add(sk, val & 0xffff, val >> 16);
3552 case PACKET_TX_HAS_OFF:
3556 if (optlen != sizeof(val))
3558 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3560 if (copy_from_user(&val, optval, sizeof(val)))
3562 po->tp_tx_has_off = !!val;
3565 case PACKET_QDISC_BYPASS:
3569 if (optlen != sizeof(val))
3571 if (copy_from_user(&val, optval, sizeof(val)))
3574 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3578 return -ENOPROTOOPT;
3582 static int packet_getsockopt(struct socket *sock, int level, int optname,
3583 char __user *optval, int __user *optlen)
3586 int val, lv = sizeof(val);
3587 struct sock *sk = sock->sk;
3588 struct packet_sock *po = pkt_sk(sk);
3590 union tpacket_stats_u st;
3591 struct tpacket_rollover_stats rstats;
3593 if (level != SOL_PACKET)
3594 return -ENOPROTOOPT;
3596 if (get_user(len, optlen))
3603 case PACKET_STATISTICS:
3604 spin_lock_bh(&sk->sk_receive_queue.lock);
3605 memcpy(&st, &po->stats, sizeof(st));
3606 memset(&po->stats, 0, sizeof(po->stats));
3607 spin_unlock_bh(&sk->sk_receive_queue.lock);
3609 if (po->tp_version == TPACKET_V3) {
3610 lv = sizeof(struct tpacket_stats_v3);
3611 st.stats3.tp_packets += st.stats3.tp_drops;
3614 lv = sizeof(struct tpacket_stats);
3615 st.stats1.tp_packets += st.stats1.tp_drops;
3620 case PACKET_AUXDATA:
3623 case PACKET_ORIGDEV:
3626 case PACKET_VNET_HDR:
3627 val = po->has_vnet_hdr;
3629 case PACKET_VERSION:
3630 val = po->tp_version;
3633 if (len > sizeof(int))
3635 if (copy_from_user(&val, optval, len))
3639 val = sizeof(struct tpacket_hdr);
3642 val = sizeof(struct tpacket2_hdr);
3645 val = sizeof(struct tpacket3_hdr);
3651 case PACKET_RESERVE:
3652 val = po->tp_reserve;
3657 case PACKET_TIMESTAMP:
3658 val = po->tp_tstamp;
3662 ((u32)po->fanout->id |
3663 ((u32)po->fanout->type << 16) |
3664 ((u32)po->fanout->flags << 24)) :
3667 case PACKET_ROLLOVER_STATS:
3670 rstats.tp_all = atomic_long_read(&po->rollover->num);
3671 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3672 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3674 lv = sizeof(rstats);
3676 case PACKET_TX_HAS_OFF:
3677 val = po->tp_tx_has_off;
3679 case PACKET_QDISC_BYPASS:
3680 val = packet_use_direct_xmit(po);
3683 return -ENOPROTOOPT;
3688 if (put_user(len, optlen))
3690 if (copy_to_user(optval, data, len))
3696 static int packet_notifier(struct notifier_block *this,
3697 unsigned long msg, void *ptr)
3700 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3701 struct net *net = dev_net(dev);
3704 sk_for_each_rcu(sk, &net->packet.sklist) {
3705 struct packet_sock *po = pkt_sk(sk);
3708 case NETDEV_UNREGISTER:
3710 packet_dev_mclist_delete(dev, &po->mclist);
3714 if (dev->ifindex == po->ifindex) {
3715 spin_lock(&po->bind_lock);
3717 __unregister_prot_hook(sk, false);
3718 sk->sk_err = ENETDOWN;
3719 if (!sock_flag(sk, SOCK_DEAD))
3720 sk->sk_error_report(sk);
3722 if (msg == NETDEV_UNREGISTER) {
3723 packet_cached_dev_reset(po);
3725 if (po->prot_hook.dev)
3726 dev_put(po->prot_hook.dev);
3727 po->prot_hook.dev = NULL;
3729 spin_unlock(&po->bind_lock);
3733 if (dev->ifindex == po->ifindex) {
3734 spin_lock(&po->bind_lock);
3736 register_prot_hook(sk);
3737 spin_unlock(&po->bind_lock);
3747 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3750 struct sock *sk = sock->sk;
3755 int amount = sk_wmem_alloc_get(sk);
3757 return put_user(amount, (int __user *)arg);
3761 struct sk_buff *skb;
3764 spin_lock_bh(&sk->sk_receive_queue.lock);
3765 skb = skb_peek(&sk->sk_receive_queue);
3768 spin_unlock_bh(&sk->sk_receive_queue.lock);
3769 return put_user(amount, (int __user *)arg);
3772 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3774 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3784 case SIOCGIFBRDADDR:
3785 case SIOCSIFBRDADDR:
3786 case SIOCGIFNETMASK:
3787 case SIOCSIFNETMASK:
3788 case SIOCGIFDSTADDR:
3789 case SIOCSIFDSTADDR:
3791 return inet_dgram_ops.ioctl(sock, cmd, arg);
3795 return -ENOIOCTLCMD;
3800 static unsigned int packet_poll(struct file *file, struct socket *sock,
3803 struct sock *sk = sock->sk;
3804 struct packet_sock *po = pkt_sk(sk);
3805 unsigned int mask = datagram_poll(file, sock, wait);
3807 spin_lock_bh(&sk->sk_receive_queue.lock);
3808 if (po->rx_ring.pg_vec) {
3809 if (!packet_previous_rx_frame(po, &po->rx_ring,
3811 mask |= POLLIN | POLLRDNORM;
3813 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
3815 spin_unlock_bh(&sk->sk_receive_queue.lock);
3816 spin_lock_bh(&sk->sk_write_queue.lock);
3817 if (po->tx_ring.pg_vec) {
3818 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3819 mask |= POLLOUT | POLLWRNORM;
3821 spin_unlock_bh(&sk->sk_write_queue.lock);
3826 /* Dirty? Well, I still did not learn better way to account
3830 static void packet_mm_open(struct vm_area_struct *vma)
3832 struct file *file = vma->vm_file;
3833 struct socket *sock = file->private_data;
3834 struct sock *sk = sock->sk;
3837 atomic_inc(&pkt_sk(sk)->mapped);
3840 static void packet_mm_close(struct vm_area_struct *vma)
3842 struct file *file = vma->vm_file;
3843 struct socket *sock = file->private_data;
3844 struct sock *sk = sock->sk;
3847 atomic_dec(&pkt_sk(sk)->mapped);
3850 static const struct vm_operations_struct packet_mmap_ops = {
3851 .open = packet_mm_open,
3852 .close = packet_mm_close,
3855 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3860 for (i = 0; i < len; i++) {
3861 if (likely(pg_vec[i].buffer)) {
3862 if (is_vmalloc_addr(pg_vec[i].buffer))
3863 vfree(pg_vec[i].buffer);
3865 free_pages((unsigned long)pg_vec[i].buffer,
3867 pg_vec[i].buffer = NULL;
3873 static char *alloc_one_pg_vec_page(unsigned long order)
3876 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3877 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3879 buffer = (char *) __get_free_pages(gfp_flags, order);
3883 /* __get_free_pages failed, fall back to vmalloc */
3884 buffer = vzalloc((1 << order) * PAGE_SIZE);
3888 /* vmalloc failed, lets dig into swap here */
3889 gfp_flags &= ~__GFP_NORETRY;
3890 buffer = (char *) __get_free_pages(gfp_flags, order);
3894 /* complete and utter failure */
3898 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3900 unsigned int block_nr = req->tp_block_nr;
3904 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3905 if (unlikely(!pg_vec))
3908 for (i = 0; i < block_nr; i++) {
3909 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3910 if (unlikely(!pg_vec[i].buffer))
3911 goto out_free_pgvec;
3918 free_pg_vec(pg_vec, order, block_nr);
3923 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3924 int closing, int tx_ring)
3926 struct pgv *pg_vec = NULL;
3927 struct packet_sock *po = pkt_sk(sk);
3928 int was_running, order = 0;
3929 struct packet_ring_buffer *rb;
3930 struct sk_buff_head *rb_queue;
3933 /* Added to avoid minimal code churn */
3934 struct tpacket_req *req = &req_u->req;
3936 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3937 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3938 WARN(1, "Tx-ring is not supported.\n");
3942 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3943 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3947 if (atomic_read(&po->mapped))
3949 if (packet_read_pending(rb))
3953 if (req->tp_block_nr) {
3954 /* Sanity tests and some calculations */
3956 if (unlikely(rb->pg_vec))
3959 switch (po->tp_version) {
3961 po->tp_hdrlen = TPACKET_HDRLEN;
3964 po->tp_hdrlen = TPACKET2_HDRLEN;
3967 po->tp_hdrlen = TPACKET3_HDRLEN;
3972 if (unlikely((int)req->tp_block_size <= 0))
3974 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3976 if (po->tp_version >= TPACKET_V3 &&
3977 (int)(req->tp_block_size -
3978 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
3980 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3983 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3986 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3987 if (unlikely(rb->frames_per_block <= 0))
3989 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3994 order = get_order(req->tp_block_size);
3995 pg_vec = alloc_pg_vec(req, order);
3996 if (unlikely(!pg_vec))
3998 switch (po->tp_version) {
4000 /* Transmit path is not supported. We checked
4001 * it above but just being paranoid
4004 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
4013 if (unlikely(req->tp_frame_nr))
4019 /* Detach socket from network */
4020 spin_lock(&po->bind_lock);
4021 was_running = po->running;
4025 __unregister_prot_hook(sk, false);
4027 spin_unlock(&po->bind_lock);
4032 mutex_lock(&po->pg_vec_lock);
4033 if (closing || atomic_read(&po->mapped) == 0) {
4035 spin_lock_bh(&rb_queue->lock);
4036 swap(rb->pg_vec, pg_vec);
4037 rb->frame_max = (req->tp_frame_nr - 1);
4039 rb->frame_size = req->tp_frame_size;
4040 spin_unlock_bh(&rb_queue->lock);
4042 swap(rb->pg_vec_order, order);
4043 swap(rb->pg_vec_len, req->tp_block_nr);
4045 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4046 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4047 tpacket_rcv : packet_rcv;
4048 skb_queue_purge(rb_queue);
4049 if (atomic_read(&po->mapped))
4050 pr_err("packet_mmap: vma is busy: %d\n",
4051 atomic_read(&po->mapped));
4053 mutex_unlock(&po->pg_vec_lock);
4055 spin_lock(&po->bind_lock);
4058 register_prot_hook(sk);
4060 spin_unlock(&po->bind_lock);
4061 if (closing && (po->tp_version > TPACKET_V2)) {
4062 /* Because we don't support block-based V3 on tx-ring */
4064 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
4069 free_pg_vec(pg_vec, order, req->tp_block_nr);
4074 static int packet_mmap(struct file *file, struct socket *sock,
4075 struct vm_area_struct *vma)
4077 struct sock *sk = sock->sk;
4078 struct packet_sock *po = pkt_sk(sk);
4079 unsigned long size, expected_size;
4080 struct packet_ring_buffer *rb;
4081 unsigned long start;
4088 mutex_lock(&po->pg_vec_lock);
4091 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4093 expected_size += rb->pg_vec_len
4099 if (expected_size == 0)
4102 size = vma->vm_end - vma->vm_start;
4103 if (size != expected_size)
4106 start = vma->vm_start;
4107 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4108 if (rb->pg_vec == NULL)
4111 for (i = 0; i < rb->pg_vec_len; i++) {
4113 void *kaddr = rb->pg_vec[i].buffer;
4116 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4117 page = pgv_to_page(kaddr);
4118 err = vm_insert_page(vma, start, page);
4127 atomic_inc(&po->mapped);
4128 vma->vm_ops = &packet_mmap_ops;
4132 mutex_unlock(&po->pg_vec_lock);
4136 static const struct proto_ops packet_ops_spkt = {
4137 .family = PF_PACKET,
4138 .owner = THIS_MODULE,
4139 .release = packet_release,
4140 .bind = packet_bind_spkt,
4141 .connect = sock_no_connect,
4142 .socketpair = sock_no_socketpair,
4143 .accept = sock_no_accept,
4144 .getname = packet_getname_spkt,
4145 .poll = datagram_poll,
4146 .ioctl = packet_ioctl,
4147 .listen = sock_no_listen,
4148 .shutdown = sock_no_shutdown,
4149 .setsockopt = sock_no_setsockopt,
4150 .getsockopt = sock_no_getsockopt,
4151 .sendmsg = packet_sendmsg_spkt,
4152 .recvmsg = packet_recvmsg,
4153 .mmap = sock_no_mmap,
4154 .sendpage = sock_no_sendpage,
4157 static const struct proto_ops packet_ops = {
4158 .family = PF_PACKET,
4159 .owner = THIS_MODULE,
4160 .release = packet_release,
4161 .bind = packet_bind,
4162 .connect = sock_no_connect,
4163 .socketpair = sock_no_socketpair,
4164 .accept = sock_no_accept,
4165 .getname = packet_getname,
4166 .poll = packet_poll,
4167 .ioctl = packet_ioctl,
4168 .listen = sock_no_listen,
4169 .shutdown = sock_no_shutdown,
4170 .setsockopt = packet_setsockopt,
4171 .getsockopt = packet_getsockopt,
4172 .sendmsg = packet_sendmsg,
4173 .recvmsg = packet_recvmsg,
4174 .mmap = packet_mmap,
4175 .sendpage = sock_no_sendpage,
4178 static const struct net_proto_family packet_family_ops = {
4179 .family = PF_PACKET,
4180 .create = packet_create,
4181 .owner = THIS_MODULE,
4184 static struct notifier_block packet_netdev_notifier = {
4185 .notifier_call = packet_notifier,
4188 #ifdef CONFIG_PROC_FS
4190 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4193 struct net *net = seq_file_net(seq);
4196 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4199 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4201 struct net *net = seq_file_net(seq);
4202 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4205 static void packet_seq_stop(struct seq_file *seq, void *v)
4211 static int packet_seq_show(struct seq_file *seq, void *v)
4213 if (v == SEQ_START_TOKEN)
4214 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4216 struct sock *s = sk_entry(v);
4217 const struct packet_sock *po = pkt_sk(s);
4220 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4222 atomic_read(&s->sk_refcnt),
4227 atomic_read(&s->sk_rmem_alloc),
4228 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4235 static const struct seq_operations packet_seq_ops = {
4236 .start = packet_seq_start,
4237 .next = packet_seq_next,
4238 .stop = packet_seq_stop,
4239 .show = packet_seq_show,
4242 static int packet_seq_open(struct inode *inode, struct file *file)
4244 return seq_open_net(inode, file, &packet_seq_ops,
4245 sizeof(struct seq_net_private));
4248 static const struct file_operations packet_seq_fops = {
4249 .owner = THIS_MODULE,
4250 .open = packet_seq_open,
4252 .llseek = seq_lseek,
4253 .release = seq_release_net,
4258 static int __net_init packet_net_init(struct net *net)
4260 mutex_init(&net->packet.sklist_lock);
4261 INIT_HLIST_HEAD(&net->packet.sklist);
4263 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4269 static void __net_exit packet_net_exit(struct net *net)
4271 remove_proc_entry("packet", net->proc_net);
4274 static struct pernet_operations packet_net_ops = {
4275 .init = packet_net_init,
4276 .exit = packet_net_exit,
4280 static void __exit packet_exit(void)
4282 unregister_netdevice_notifier(&packet_netdev_notifier);
4283 unregister_pernet_subsys(&packet_net_ops);
4284 sock_unregister(PF_PACKET);
4285 proto_unregister(&packet_proto);
4288 static int __init packet_init(void)
4290 int rc = proto_register(&packet_proto, 0);
4295 sock_register(&packet_family_ops);
4296 register_pernet_subsys(&packet_net_ops);
4297 register_netdevice_notifier(&packet_netdev_notifier);
4302 module_init(packet_init);
4303 module_exit(packet_exit);
4304 MODULE_LICENSE("GPL");
4305 MODULE_ALIAS_NETPROTO(PF_PACKET);