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>
95 #include <linux/bpf.h>
96 #include <net/compat.h>
102 - if device has no dev->hard_header routine, it adds and removes ll header
103 inside itself. In this case ll header is invisible outside of device,
104 but higher levels still should reserve dev->hard_header_len.
105 Some devices are enough clever to reallocate skb, when header
106 will not fit to reserved space (tunnel), another ones are silly
108 - packet socket receives packets with pulled ll header,
109 so that SOCK_RAW should push it back.
114 Incoming, dev->hard_header!=NULL
115 mac_header -> ll header
118 Outgoing, dev->hard_header!=NULL
119 mac_header -> ll header
122 Incoming, dev->hard_header==NULL
123 mac_header -> UNKNOWN position. It is very likely, that it points to ll
124 header. PPP makes it, that is wrong, because introduce
125 assymetry between rx and tx paths.
128 Outgoing, dev->hard_header==NULL
129 mac_header -> data. ll header is still not built!
133 If dev->hard_header==NULL we are unlikely to restore sensible ll header.
139 dev->hard_header != NULL
140 mac_header -> ll header
143 dev->hard_header == NULL (ll header is added by device, we cannot control it)
147 We should set nh.raw on output to correct posistion,
148 packet classifier depends on it.
151 /* Private packet socket structures. */
153 /* identical to struct packet_mreq except it has
154 * a longer address field.
156 struct packet_mreq_max {
158 unsigned short mr_type;
159 unsigned short mr_alen;
160 unsigned char mr_address[MAX_ADDR_LEN];
164 struct tpacket_hdr *h1;
165 struct tpacket2_hdr *h2;
166 struct tpacket3_hdr *h3;
170 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
171 int closing, int tx_ring);
173 #define V3_ALIGNMENT (8)
175 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
177 #define BLK_PLUS_PRIV(sz_of_priv) \
178 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
180 #define PGV_FROM_VMALLOC 1
182 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
183 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
184 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
185 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
186 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
187 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
188 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
191 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
192 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
193 struct packet_type *pt, struct net_device *orig_dev);
195 static void *packet_previous_frame(struct packet_sock *po,
196 struct packet_ring_buffer *rb,
198 static void packet_increment_head(struct packet_ring_buffer *buff);
199 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
200 struct tpacket_block_desc *);
201 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
202 struct packet_sock *);
203 static void prb_retire_current_block(struct tpacket_kbdq_core *,
204 struct packet_sock *, unsigned int status);
205 static int prb_queue_frozen(struct tpacket_kbdq_core *);
206 static void prb_open_block(struct tpacket_kbdq_core *,
207 struct tpacket_block_desc *);
208 static void prb_retire_rx_blk_timer_expired(unsigned long);
209 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
210 static void prb_init_blk_timer(struct packet_sock *,
211 struct tpacket_kbdq_core *,
212 void (*func) (unsigned long));
213 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
214 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
215 struct tpacket3_hdr *);
216 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
217 struct tpacket3_hdr *);
218 static void packet_flush_mclist(struct sock *sk);
220 struct packet_skb_cb {
222 struct sockaddr_pkt pkt;
224 /* Trick: alias skb original length with
225 * ll.sll_family and ll.protocol in order
228 unsigned int origlen;
229 struct sockaddr_ll ll;
234 #define vio_le() virtio_legacy_is_little_endian()
236 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
238 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
239 #define GET_PBLOCK_DESC(x, bid) \
240 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
241 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
242 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
243 #define GET_NEXT_PRB_BLK_NUM(x) \
244 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
245 ((x)->kactive_blk_num+1) : 0)
247 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
248 static void __fanout_link(struct sock *sk, struct packet_sock *po);
250 static int packet_direct_xmit(struct sk_buff *skb)
252 struct net_device *dev = skb->dev;
253 struct sk_buff *orig_skb = skb;
254 struct netdev_queue *txq;
255 int ret = NETDEV_TX_BUSY;
257 if (unlikely(!netif_running(dev) ||
258 !netif_carrier_ok(dev)))
261 skb = validate_xmit_skb_list(skb, dev);
265 txq = skb_get_tx_queue(dev, skb);
269 HARD_TX_LOCK(dev, txq, smp_processor_id());
270 if (!netif_xmit_frozen_or_drv_stopped(txq))
271 ret = netdev_start_xmit(skb, dev, txq, false);
272 HARD_TX_UNLOCK(dev, txq);
276 if (!dev_xmit_complete(ret))
281 atomic_long_inc(&dev->tx_dropped);
283 return NET_XMIT_DROP;
286 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
288 struct net_device *dev;
291 dev = rcu_dereference(po->cached_dev);
299 static void packet_cached_dev_assign(struct packet_sock *po,
300 struct net_device *dev)
302 rcu_assign_pointer(po->cached_dev, dev);
305 static void packet_cached_dev_reset(struct packet_sock *po)
307 RCU_INIT_POINTER(po->cached_dev, NULL);
310 static bool packet_use_direct_xmit(const struct packet_sock *po)
312 return po->xmit == packet_direct_xmit;
315 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
317 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
320 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
322 const struct net_device_ops *ops = dev->netdev_ops;
325 if (ops->ndo_select_queue) {
326 queue_index = ops->ndo_select_queue(dev, skb, NULL,
327 __packet_pick_tx_queue);
328 queue_index = netdev_cap_txqueue(dev, queue_index);
330 queue_index = __packet_pick_tx_queue(dev, skb);
333 skb_set_queue_mapping(skb, queue_index);
336 /* register_prot_hook must be invoked with the po->bind_lock held,
337 * or from a context in which asynchronous accesses to the packet
338 * socket is not possible (packet_create()).
340 static void register_prot_hook(struct sock *sk)
342 struct packet_sock *po = pkt_sk(sk);
346 __fanout_link(sk, po);
348 dev_add_pack(&po->prot_hook);
355 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
356 * held. If the sync parameter is true, we will temporarily drop
357 * the po->bind_lock and do a synchronize_net to make sure no
358 * asynchronous packet processing paths still refer to the elements
359 * of po->prot_hook. If the sync parameter is false, it is the
360 * callers responsibility to take care of this.
362 static void __unregister_prot_hook(struct sock *sk, bool sync)
364 struct packet_sock *po = pkt_sk(sk);
369 __fanout_unlink(sk, po);
371 __dev_remove_pack(&po->prot_hook);
376 spin_unlock(&po->bind_lock);
378 spin_lock(&po->bind_lock);
382 static void unregister_prot_hook(struct sock *sk, bool sync)
384 struct packet_sock *po = pkt_sk(sk);
387 __unregister_prot_hook(sk, sync);
390 static inline struct page * __pure pgv_to_page(void *addr)
392 if (is_vmalloc_addr(addr))
393 return vmalloc_to_page(addr);
394 return virt_to_page(addr);
397 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
399 union tpacket_uhdr h;
402 switch (po->tp_version) {
404 h.h1->tp_status = status;
405 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
408 h.h2->tp_status = status;
409 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
413 WARN(1, "TPACKET version not supported.\n");
420 static int __packet_get_status(struct packet_sock *po, void *frame)
422 union tpacket_uhdr h;
427 switch (po->tp_version) {
429 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
430 return h.h1->tp_status;
432 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
433 return h.h2->tp_status;
436 WARN(1, "TPACKET version not supported.\n");
442 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
445 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
448 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
449 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
450 return TP_STATUS_TS_RAW_HARDWARE;
452 if (ktime_to_timespec_cond(skb->tstamp, ts))
453 return TP_STATUS_TS_SOFTWARE;
458 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
461 union tpacket_uhdr h;
465 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
469 switch (po->tp_version) {
471 h.h1->tp_sec = ts.tv_sec;
472 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
475 h.h2->tp_sec = ts.tv_sec;
476 h.h2->tp_nsec = ts.tv_nsec;
480 WARN(1, "TPACKET version not supported.\n");
484 /* one flush is safe, as both fields always lie on the same cacheline */
485 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
491 static void *packet_lookup_frame(struct packet_sock *po,
492 struct packet_ring_buffer *rb,
493 unsigned int position,
496 unsigned int pg_vec_pos, frame_offset;
497 union tpacket_uhdr h;
499 pg_vec_pos = position / rb->frames_per_block;
500 frame_offset = position % rb->frames_per_block;
502 h.raw = rb->pg_vec[pg_vec_pos].buffer +
503 (frame_offset * rb->frame_size);
505 if (status != __packet_get_status(po, h.raw))
511 static void *packet_current_frame(struct packet_sock *po,
512 struct packet_ring_buffer *rb,
515 return packet_lookup_frame(po, rb, rb->head, status);
518 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
520 del_timer_sync(&pkc->retire_blk_timer);
523 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
524 struct sk_buff_head *rb_queue)
526 struct tpacket_kbdq_core *pkc;
528 pkc = 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)
549 struct tpacket_kbdq_core *pkc;
551 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
552 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
555 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
556 int blk_size_in_bytes)
558 struct net_device *dev;
559 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
560 struct ethtool_link_ksettings ecmd;
564 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
565 if (unlikely(!dev)) {
567 return DEFAULT_PRB_RETIRE_TOV;
569 err = __ethtool_get_link_ksettings(dev, &ecmd);
573 * If the link speed is so slow you don't really
574 * need to worry about perf anyways
576 if (ecmd.base.speed < SPEED_1000 ||
577 ecmd.base.speed == SPEED_UNKNOWN) {
578 return DEFAULT_PRB_RETIRE_TOV;
581 div = ecmd.base.speed / 1000;
585 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
597 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
598 union tpacket_req_u *req_u)
600 p1->feature_req_word = req_u->req3.tp_feature_req_word;
603 static void init_prb_bdqc(struct packet_sock *po,
604 struct packet_ring_buffer *rb,
606 union tpacket_req_u *req_u)
608 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
609 struct tpacket_block_desc *pbd;
611 memset(p1, 0x0, sizeof(*p1));
613 p1->knxt_seq_num = 1;
615 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
616 p1->pkblk_start = pg_vec[0].buffer;
617 p1->kblk_size = req_u->req3.tp_block_size;
618 p1->knum_blocks = req_u->req3.tp_block_nr;
619 p1->hdrlen = po->tp_hdrlen;
620 p1->version = po->tp_version;
621 p1->last_kactive_blk_num = 0;
622 po->stats.stats3.tp_freeze_q_cnt = 0;
623 if (req_u->req3.tp_retire_blk_tov)
624 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
626 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
627 req_u->req3.tp_block_size);
628 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
629 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
631 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
632 prb_init_ft_ops(p1, req_u);
633 prb_setup_retire_blk_timer(po);
634 prb_open_block(p1, pbd);
637 /* Do NOT update the last_blk_num first.
638 * Assumes sk_buff_head lock is held.
640 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
642 mod_timer(&pkc->retire_blk_timer,
643 jiffies + pkc->tov_in_jiffies);
644 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
649 * 1) We refresh the timer only when we open a block.
650 * By doing this we don't waste cycles refreshing the timer
651 * on packet-by-packet basis.
653 * With a 1MB block-size, on a 1Gbps line, it will take
654 * i) ~8 ms to fill a block + ii) memcpy etc.
655 * In this cut we are not accounting for the memcpy time.
657 * So, if the user sets the 'tmo' to 10ms then the timer
658 * will never fire while the block is still getting filled
659 * (which is what we want). However, the user could choose
660 * to close a block early and that's fine.
662 * But when the timer does fire, we check whether or not to refresh it.
663 * Since the tmo granularity is in msecs, it is not too expensive
664 * to refresh the timer, lets say every '8' msecs.
665 * Either the user can set the 'tmo' or we can derive it based on
666 * a) line-speed and b) block-size.
667 * prb_calc_retire_blk_tmo() calculates the tmo.
670 static void prb_retire_rx_blk_timer_expired(unsigned long data)
672 struct packet_sock *po = (struct packet_sock *)data;
673 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
675 struct tpacket_block_desc *pbd;
677 spin_lock(&po->sk.sk_receive_queue.lock);
679 frozen = prb_queue_frozen(pkc);
680 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
682 if (unlikely(pkc->delete_blk_timer))
685 /* We only need to plug the race when the block is partially filled.
687 * lock(); increment BLOCK_NUM_PKTS; unlock()
688 * copy_bits() is in progress ...
689 * timer fires on other cpu:
690 * we can't retire the current block because copy_bits
694 if (BLOCK_NUM_PKTS(pbd)) {
695 while (atomic_read(&pkc->blk_fill_in_prog)) {
696 /* Waiting for skb_copy_bits to finish... */
701 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
703 if (!BLOCK_NUM_PKTS(pbd)) {
704 /* An empty block. Just refresh the timer. */
707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
708 if (!prb_dispatch_next_block(pkc, po))
713 /* Case 1. Queue was frozen because user-space was
716 if (prb_curr_blk_in_use(pkc, pbd)) {
718 * Ok, user-space is still behind.
719 * So just refresh the timer.
723 /* Case 2. queue was frozen,user-space caught up,
724 * now the link went idle && the timer fired.
725 * We don't have a block to close.So we open this
726 * block and restart the timer.
727 * opening a block thaws the queue,restarts timer
728 * Thawing/timer-refresh is a side effect.
730 prb_open_block(pkc, pbd);
737 _prb_refresh_rx_retire_blk_timer(pkc);
740 spin_unlock(&po->sk.sk_receive_queue.lock);
743 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
744 struct tpacket_block_desc *pbd1, __u32 status)
746 /* Flush everything minus the block header */
748 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
753 /* Skip the block header(we know header WILL fit in 4K) */
756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
757 for (; start < end; start += PAGE_SIZE)
758 flush_dcache_page(pgv_to_page(start));
763 /* Now update the block status. */
765 BLOCK_STATUS(pbd1) = status;
767 /* Flush the block header */
769 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
771 flush_dcache_page(pgv_to_page(start));
781 * 2) Increment active_blk_num
783 * Note:We DONT refresh the timer on purpose.
784 * Because almost always the next block will be opened.
786 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
787 struct tpacket_block_desc *pbd1,
788 struct packet_sock *po, unsigned int stat)
790 __u32 status = TP_STATUS_USER | stat;
792 struct tpacket3_hdr *last_pkt;
793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
794 struct sock *sk = &po->sk;
796 if (po->stats.stats3.tp_drops)
797 status |= TP_STATUS_LOSING;
799 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
800 last_pkt->tp_next_offset = 0;
802 /* Get the ts of the last pkt */
803 if (BLOCK_NUM_PKTS(pbd1)) {
804 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
805 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
807 /* Ok, we tmo'd - so get the current time.
809 * It shouldn't really happen as we don't close empty
810 * blocks. See prb_retire_rx_blk_timer_expired().
814 h1->ts_last_pkt.ts_sec = ts.tv_sec;
815 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
820 /* Flush the block */
821 prb_flush_block(pkc1, pbd1, status);
823 sk->sk_data_ready(sk);
825 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
828 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
830 pkc->reset_pending_on_curr_blk = 0;
834 * Side effect of opening a block:
836 * 1) prb_queue is thawed.
837 * 2) retire_blk_timer is refreshed.
840 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
841 struct tpacket_block_desc *pbd1)
844 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
848 /* We could have just memset this but we will lose the
849 * flexibility of making the priv area sticky
852 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
853 BLOCK_NUM_PKTS(pbd1) = 0;
854 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
858 h1->ts_first_pkt.ts_sec = ts.tv_sec;
859 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
861 pkc1->pkblk_start = (char *)pbd1;
862 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
864 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
865 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
867 pbd1->version = pkc1->version;
868 pkc1->prev = pkc1->nxt_offset;
869 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
871 prb_thaw_queue(pkc1);
872 _prb_refresh_rx_retire_blk_timer(pkc1);
878 * Queue freeze logic:
879 * 1) Assume tp_block_nr = 8 blocks.
880 * 2) At time 't0', user opens Rx ring.
881 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
882 * 4) user-space is either sleeping or processing block '0'.
883 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
884 * it will close block-7,loop around and try to fill block '0'.
886 * __packet_lookup_frame_in_block
887 * prb_retire_current_block()
888 * prb_dispatch_next_block()
889 * |->(BLOCK_STATUS == USER) evaluates to true
890 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
891 * 6) Now there are two cases:
892 * 6.1) Link goes idle right after the queue is frozen.
893 * But remember, the last open_block() refreshed the timer.
894 * When this timer expires,it will refresh itself so that we can
895 * re-open block-0 in near future.
896 * 6.2) Link is busy and keeps on receiving packets. This is a simple
897 * case and __packet_lookup_frame_in_block will check if block-0
898 * is free and can now be re-used.
900 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
901 struct packet_sock *po)
903 pkc->reset_pending_on_curr_blk = 1;
904 po->stats.stats3.tp_freeze_q_cnt++;
907 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
910 * If the next block is free then we will dispatch it
911 * and return a good offset.
912 * Else, we will freeze the queue.
913 * So, caller must check the return value.
915 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
916 struct packet_sock *po)
918 struct tpacket_block_desc *pbd;
922 /* 1. Get current block num */
923 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
925 /* 2. If this block is currently in_use then freeze the queue */
926 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
927 prb_freeze_queue(pkc, po);
933 * open this block and return the offset where the first packet
934 * needs to get stored.
936 prb_open_block(pkc, pbd);
937 return (void *)pkc->nxt_offset;
940 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
941 struct packet_sock *po, unsigned int status)
943 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
945 /* retire/close the current block */
946 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
948 * Plug the case where copy_bits() is in progress on
949 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
950 * have space to copy the pkt in the current block and
951 * called prb_retire_current_block()
953 * We don't need to worry about the TMO case because
954 * the timer-handler already handled this case.
956 if (!(status & TP_STATUS_BLK_TMO)) {
957 while (atomic_read(&pkc->blk_fill_in_prog)) {
958 /* Waiting for skb_copy_bits to finish... */
962 prb_close_block(pkc, pbd, po, status);
967 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
968 struct tpacket_block_desc *pbd)
970 return TP_STATUS_USER & BLOCK_STATUS(pbd);
973 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
975 return pkc->reset_pending_on_curr_blk;
978 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
980 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
981 atomic_dec(&pkc->blk_fill_in_prog);
984 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
985 struct tpacket3_hdr *ppd)
987 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
990 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
991 struct tpacket3_hdr *ppd)
993 ppd->hv1.tp_rxhash = 0;
996 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
997 struct tpacket3_hdr *ppd)
999 if (skb_vlan_tag_present(pkc->skb)) {
1000 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1001 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1002 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1004 ppd->hv1.tp_vlan_tci = 0;
1005 ppd->hv1.tp_vlan_tpid = 0;
1006 ppd->tp_status = TP_STATUS_AVAILABLE;
1010 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1011 struct tpacket3_hdr *ppd)
1013 ppd->hv1.tp_padding = 0;
1014 prb_fill_vlan_info(pkc, ppd);
1016 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1017 prb_fill_rxhash(pkc, ppd);
1019 prb_clear_rxhash(pkc, ppd);
1022 static void prb_fill_curr_block(char *curr,
1023 struct tpacket_kbdq_core *pkc,
1024 struct tpacket_block_desc *pbd,
1027 struct tpacket3_hdr *ppd;
1029 ppd = (struct tpacket3_hdr *)curr;
1030 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1032 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1033 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1034 BLOCK_NUM_PKTS(pbd) += 1;
1035 atomic_inc(&pkc->blk_fill_in_prog);
1036 prb_run_all_ft_ops(pkc, ppd);
1039 /* Assumes caller has the sk->rx_queue.lock */
1040 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1041 struct sk_buff *skb,
1046 struct tpacket_kbdq_core *pkc;
1047 struct tpacket_block_desc *pbd;
1050 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1051 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1053 /* Queue is frozen when user space is lagging behind */
1054 if (prb_queue_frozen(pkc)) {
1056 * Check if that last block which caused the queue to freeze,
1057 * is still in_use by user-space.
1059 if (prb_curr_blk_in_use(pkc, pbd)) {
1060 /* Can't record this packet */
1064 * Ok, the block was released by user-space.
1065 * Now let's open that block.
1066 * opening a block also thaws the queue.
1067 * Thawing is a side effect.
1069 prb_open_block(pkc, pbd);
1074 curr = pkc->nxt_offset;
1076 end = (char *)pbd + pkc->kblk_size;
1078 /* first try the current block */
1079 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1080 prb_fill_curr_block(curr, pkc, pbd, len);
1081 return (void *)curr;
1084 /* Ok, close the current block */
1085 prb_retire_current_block(pkc, po, 0);
1087 /* Now, try to dispatch the next block */
1088 curr = (char *)prb_dispatch_next_block(pkc, po);
1090 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1091 prb_fill_curr_block(curr, pkc, pbd, len);
1092 return (void *)curr;
1096 * No free blocks are available.user_space hasn't caught up yet.
1097 * Queue was just frozen and now this packet will get dropped.
1102 static void *packet_current_rx_frame(struct packet_sock *po,
1103 struct sk_buff *skb,
1104 int status, unsigned int len)
1107 switch (po->tp_version) {
1110 curr = packet_lookup_frame(po, &po->rx_ring,
1111 po->rx_ring.head, status);
1114 return __packet_lookup_frame_in_block(po, skb, status, len);
1116 WARN(1, "TPACKET version not supported\n");
1122 static void *prb_lookup_block(struct packet_sock *po,
1123 struct packet_ring_buffer *rb,
1127 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1128 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1130 if (status != BLOCK_STATUS(pbd))
1135 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1138 if (rb->prb_bdqc.kactive_blk_num)
1139 prev = rb->prb_bdqc.kactive_blk_num-1;
1141 prev = rb->prb_bdqc.knum_blocks-1;
1145 /* Assumes caller has held the rx_queue.lock */
1146 static void *__prb_previous_block(struct packet_sock *po,
1147 struct packet_ring_buffer *rb,
1150 unsigned int previous = prb_previous_blk_num(rb);
1151 return prb_lookup_block(po, rb, previous, status);
1154 static void *packet_previous_rx_frame(struct packet_sock *po,
1155 struct packet_ring_buffer *rb,
1158 if (po->tp_version <= TPACKET_V2)
1159 return packet_previous_frame(po, rb, status);
1161 return __prb_previous_block(po, rb, status);
1164 static void packet_increment_rx_head(struct packet_sock *po,
1165 struct packet_ring_buffer *rb)
1167 switch (po->tp_version) {
1170 return packet_increment_head(rb);
1173 WARN(1, "TPACKET version not supported.\n");
1179 static void *packet_previous_frame(struct packet_sock *po,
1180 struct packet_ring_buffer *rb,
1183 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1184 return packet_lookup_frame(po, rb, previous, status);
1187 static void packet_increment_head(struct packet_ring_buffer *buff)
1189 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1192 static void packet_inc_pending(struct packet_ring_buffer *rb)
1194 this_cpu_inc(*rb->pending_refcnt);
1197 static void packet_dec_pending(struct packet_ring_buffer *rb)
1199 this_cpu_dec(*rb->pending_refcnt);
1202 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1204 unsigned int refcnt = 0;
1207 /* We don't use pending refcount in rx_ring. */
1208 if (rb->pending_refcnt == NULL)
1211 for_each_possible_cpu(cpu)
1212 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1217 static int packet_alloc_pending(struct packet_sock *po)
1219 po->rx_ring.pending_refcnt = NULL;
1221 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1222 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1228 static void packet_free_pending(struct packet_sock *po)
1230 free_percpu(po->tx_ring.pending_refcnt);
1233 #define ROOM_POW_OFF 2
1234 #define ROOM_NONE 0x0
1235 #define ROOM_LOW 0x1
1236 #define ROOM_NORMAL 0x2
1238 static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1242 len = po->rx_ring.frame_max + 1;
1243 idx = po->rx_ring.head;
1245 idx += len >> pow_off;
1248 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1251 static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1255 len = po->rx_ring.prb_bdqc.knum_blocks;
1256 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1258 idx += len >> pow_off;
1261 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1264 static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1266 struct sock *sk = &po->sk;
1267 int ret = ROOM_NONE;
1269 if (po->prot_hook.func != tpacket_rcv) {
1270 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1271 - (skb ? skb->truesize : 0);
1272 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1280 if (po->tp_version == TPACKET_V3) {
1281 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1283 else if (__tpacket_v3_has_room(po, 0))
1286 if (__tpacket_has_room(po, ROOM_POW_OFF))
1288 else if (__tpacket_has_room(po, 0))
1295 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1300 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1301 ret = __packet_rcv_has_room(po, skb);
1302 has_room = ret == ROOM_NORMAL;
1303 if (po->pressure == has_room)
1304 po->pressure = !has_room;
1305 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1310 static void packet_sock_destruct(struct sock *sk)
1312 skb_queue_purge(&sk->sk_error_queue);
1314 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1315 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1317 if (!sock_flag(sk, SOCK_DEAD)) {
1318 pr_err("Attempt to release alive packet socket: %p\n", sk);
1322 sk_refcnt_debug_dec(sk);
1325 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1330 rxhash = skb_get_hash(skb);
1331 for (i = 0; i < ROLLOVER_HLEN; i++)
1332 if (po->rollover->history[i] == rxhash)
1335 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1336 return count > (ROLLOVER_HLEN >> 1);
1339 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1340 struct sk_buff *skb,
1343 return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1346 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1347 struct sk_buff *skb,
1350 unsigned int val = atomic_inc_return(&f->rr_cur);
1355 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1356 struct sk_buff *skb,
1359 return smp_processor_id() % num;
1362 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1363 struct sk_buff *skb,
1366 return prandom_u32_max(num);
1369 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1370 struct sk_buff *skb,
1371 unsigned int idx, bool try_self,
1374 struct packet_sock *po, *po_next, *po_skip = NULL;
1375 unsigned int i, j, room = ROOM_NONE;
1377 po = pkt_sk(f->arr[idx]);
1380 room = packet_rcv_has_room(po, skb);
1381 if (room == ROOM_NORMAL ||
1382 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1387 i = j = min_t(int, po->rollover->sock, num - 1);
1389 po_next = pkt_sk(f->arr[i]);
1390 if (po_next != po_skip && !po_next->pressure &&
1391 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1393 po->rollover->sock = i;
1394 atomic_long_inc(&po->rollover->num);
1395 if (room == ROOM_LOW)
1396 atomic_long_inc(&po->rollover->num_huge);
1404 atomic_long_inc(&po->rollover->num_failed);
1408 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1409 struct sk_buff *skb,
1412 return skb_get_queue_mapping(skb) % num;
1415 static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1416 struct sk_buff *skb,
1419 struct bpf_prog *prog;
1420 unsigned int ret = 0;
1423 prog = rcu_dereference(f->bpf_prog);
1425 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1431 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1433 return f->flags & (flag >> 8);
1436 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1437 struct packet_type *pt, struct net_device *orig_dev)
1439 struct packet_fanout *f = pt->af_packet_priv;
1440 unsigned int num = READ_ONCE(f->num_members);
1441 struct net *net = read_pnet(&f->net);
1442 struct packet_sock *po;
1445 if (!net_eq(dev_net(dev), net) || !num) {
1450 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1451 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1456 case PACKET_FANOUT_HASH:
1458 idx = fanout_demux_hash(f, skb, num);
1460 case PACKET_FANOUT_LB:
1461 idx = fanout_demux_lb(f, skb, num);
1463 case PACKET_FANOUT_CPU:
1464 idx = fanout_demux_cpu(f, skb, num);
1466 case PACKET_FANOUT_RND:
1467 idx = fanout_demux_rnd(f, skb, num);
1469 case PACKET_FANOUT_QM:
1470 idx = fanout_demux_qm(f, skb, num);
1472 case PACKET_FANOUT_ROLLOVER:
1473 idx = fanout_demux_rollover(f, skb, 0, false, num);
1475 case PACKET_FANOUT_CBPF:
1476 case PACKET_FANOUT_EBPF:
1477 idx = fanout_demux_bpf(f, skb, num);
1481 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1482 idx = fanout_demux_rollover(f, skb, idx, true, num);
1484 po = pkt_sk(f->arr[idx]);
1485 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1488 DEFINE_MUTEX(fanout_mutex);
1489 EXPORT_SYMBOL_GPL(fanout_mutex);
1490 static LIST_HEAD(fanout_list);
1492 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1494 struct packet_fanout *f = po->fanout;
1496 spin_lock(&f->lock);
1497 f->arr[f->num_members] = sk;
1500 spin_unlock(&f->lock);
1503 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1505 struct packet_fanout *f = po->fanout;
1508 spin_lock(&f->lock);
1509 for (i = 0; i < f->num_members; i++) {
1510 if (f->arr[i] == sk)
1513 BUG_ON(i >= f->num_members);
1514 f->arr[i] = f->arr[f->num_members - 1];
1516 spin_unlock(&f->lock);
1519 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1521 if (sk->sk_family != PF_PACKET)
1524 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1527 static void fanout_init_data(struct packet_fanout *f)
1530 case PACKET_FANOUT_LB:
1531 atomic_set(&f->rr_cur, 0);
1533 case PACKET_FANOUT_CBPF:
1534 case PACKET_FANOUT_EBPF:
1535 RCU_INIT_POINTER(f->bpf_prog, NULL);
1540 static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1542 struct bpf_prog *old;
1544 spin_lock(&f->lock);
1545 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1546 rcu_assign_pointer(f->bpf_prog, new);
1547 spin_unlock(&f->lock);
1551 bpf_prog_destroy(old);
1555 static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1558 struct bpf_prog *new;
1559 struct sock_fprog fprog;
1562 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1564 if (len != sizeof(fprog))
1566 if (copy_from_user(&fprog, data, len))
1569 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1573 __fanout_set_data_bpf(po->fanout, new);
1577 static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1580 struct bpf_prog *new;
1583 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1585 if (len != sizeof(fd))
1587 if (copy_from_user(&fd, data, len))
1590 new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1592 return PTR_ERR(new);
1594 __fanout_set_data_bpf(po->fanout, new);
1598 static int fanout_set_data(struct packet_sock *po, char __user *data,
1601 switch (po->fanout->type) {
1602 case PACKET_FANOUT_CBPF:
1603 return fanout_set_data_cbpf(po, data, len);
1604 case PACKET_FANOUT_EBPF:
1605 return fanout_set_data_ebpf(po, data, len);
1611 static void fanout_release_data(struct packet_fanout *f)
1614 case PACKET_FANOUT_CBPF:
1615 case PACKET_FANOUT_EBPF:
1616 __fanout_set_data_bpf(f, NULL);
1620 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1622 struct packet_sock *po = pkt_sk(sk);
1623 struct packet_fanout *f, *match;
1624 u8 type = type_flags & 0xff;
1625 u8 flags = type_flags >> 8;
1629 case PACKET_FANOUT_ROLLOVER:
1630 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1632 case PACKET_FANOUT_HASH:
1633 case PACKET_FANOUT_LB:
1634 case PACKET_FANOUT_CPU:
1635 case PACKET_FANOUT_RND:
1636 case PACKET_FANOUT_QM:
1637 case PACKET_FANOUT_CBPF:
1638 case PACKET_FANOUT_EBPF:
1650 if (type == PACKET_FANOUT_ROLLOVER ||
1651 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1652 po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
1655 atomic_long_set(&po->rollover->num, 0);
1656 atomic_long_set(&po->rollover->num_huge, 0);
1657 atomic_long_set(&po->rollover->num_failed, 0);
1660 mutex_lock(&fanout_mutex);
1662 list_for_each_entry(f, &fanout_list, list) {
1664 read_pnet(&f->net) == sock_net(sk)) {
1670 if (match && match->flags != flags)
1674 match = kzalloc(sizeof(*match), GFP_KERNEL);
1677 write_pnet(&match->net, sock_net(sk));
1680 match->flags = flags;
1681 INIT_LIST_HEAD(&match->list);
1682 spin_lock_init(&match->lock);
1683 atomic_set(&match->sk_ref, 0);
1684 fanout_init_data(match);
1685 match->prot_hook.type = po->prot_hook.type;
1686 match->prot_hook.dev = po->prot_hook.dev;
1687 match->prot_hook.func = packet_rcv_fanout;
1688 match->prot_hook.af_packet_priv = match;
1689 match->prot_hook.id_match = match_fanout_group;
1690 dev_add_pack(&match->prot_hook);
1691 list_add(&match->list, &fanout_list);
1694 if (match->type == type &&
1695 match->prot_hook.type == po->prot_hook.type &&
1696 match->prot_hook.dev == po->prot_hook.dev) {
1698 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1699 __dev_remove_pack(&po->prot_hook);
1701 atomic_inc(&match->sk_ref);
1702 __fanout_link(sk, po);
1707 mutex_unlock(&fanout_mutex);
1709 kfree(po->rollover);
1710 po->rollover = NULL;
1715 static void fanout_release(struct sock *sk)
1717 struct packet_sock *po = pkt_sk(sk);
1718 struct packet_fanout *f;
1724 mutex_lock(&fanout_mutex);
1727 if (atomic_dec_and_test(&f->sk_ref)) {
1729 dev_remove_pack(&f->prot_hook);
1730 fanout_release_data(f);
1733 mutex_unlock(&fanout_mutex);
1736 kfree_rcu(po->rollover, rcu);
1739 static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1740 struct sk_buff *skb)
1742 /* Earlier code assumed this would be a VLAN pkt, double-check
1743 * this now that we have the actual packet in hand. We can only
1744 * do this check on Ethernet devices.
1746 if (unlikely(dev->type != ARPHRD_ETHER))
1749 skb_reset_mac_header(skb);
1750 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1753 static const struct proto_ops packet_ops;
1755 static const struct proto_ops packet_ops_spkt;
1757 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1758 struct packet_type *pt, struct net_device *orig_dev)
1761 struct sockaddr_pkt *spkt;
1764 * When we registered the protocol we saved the socket in the data
1765 * field for just this event.
1768 sk = pt->af_packet_priv;
1771 * Yank back the headers [hope the device set this
1772 * right or kerboom...]
1774 * Incoming packets have ll header pulled,
1777 * For outgoing ones skb->data == skb_mac_header(skb)
1778 * so that this procedure is noop.
1781 if (skb->pkt_type == PACKET_LOOPBACK)
1784 if (!net_eq(dev_net(dev), sock_net(sk)))
1787 skb = skb_share_check(skb, GFP_ATOMIC);
1791 /* drop any routing info */
1794 /* drop conntrack reference */
1797 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1799 skb_push(skb, skb->data - skb_mac_header(skb));
1802 * The SOCK_PACKET socket receives _all_ frames.
1805 spkt->spkt_family = dev->type;
1806 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1807 spkt->spkt_protocol = skb->protocol;
1810 * Charge the memory to the socket. This is done specifically
1811 * to prevent sockets using all the memory up.
1814 if (sock_queue_rcv_skb(sk, skb) == 0)
1825 * Output a raw packet to a device layer. This bypasses all the other
1826 * protocol layers and you must therefore supply it with a complete frame
1829 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1832 struct sock *sk = sock->sk;
1833 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1834 struct sk_buff *skb = NULL;
1835 struct net_device *dev;
1836 struct sockcm_cookie sockc;
1842 * Get and verify the address.
1846 if (msg->msg_namelen < sizeof(struct sockaddr))
1848 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1849 proto = saddr->spkt_protocol;
1851 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1854 * Find the device first to size check it
1857 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1860 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1866 if (!(dev->flags & IFF_UP))
1870 * You may not queue a frame bigger than the mtu. This is the lowest level
1871 * raw protocol and you must do your own fragmentation at this level.
1874 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1875 if (!netif_supports_nofcs(dev)) {
1876 err = -EPROTONOSUPPORT;
1879 extra_len = 4; /* We're doing our own CRC */
1883 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1887 size_t reserved = LL_RESERVED_SPACE(dev);
1888 int tlen = dev->needed_tailroom;
1889 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1892 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1895 /* FIXME: Save some space for broken drivers that write a hard
1896 * header at transmission time by themselves. PPP is the notable
1897 * one here. This should really be fixed at the driver level.
1899 skb_reserve(skb, reserved);
1900 skb_reset_network_header(skb);
1902 /* Try to align data part correctly */
1907 skb_reset_network_header(skb);
1909 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1915 if (!dev_validate_header(dev, skb->data, len)) {
1919 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1920 !packet_extra_vlan_len_allowed(dev, skb)) {
1925 sockc.tsflags = sk->sk_tsflags;
1926 if (msg->msg_controllen) {
1927 err = sock_cmsg_send(sk, msg, &sockc);
1932 skb->protocol = proto;
1934 skb->priority = sk->sk_priority;
1935 skb->mark = sk->sk_mark;
1937 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
1939 if (unlikely(extra_len == 4))
1942 skb_probe_transport_header(skb, 0);
1944 dev_queue_xmit(skb);
1955 static unsigned int run_filter(struct sk_buff *skb,
1956 const struct sock *sk,
1959 struct sk_filter *filter;
1962 filter = rcu_dereference(sk->sk_filter);
1964 res = bpf_prog_run_clear_cb(filter->prog, skb);
1970 static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
1973 struct virtio_net_hdr vnet_hdr;
1975 if (*len < sizeof(vnet_hdr))
1977 *len -= sizeof(vnet_hdr);
1979 if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le()))
1982 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
1986 * This function makes lazy skb cloning in hope that most of packets
1987 * are discarded by BPF.
1989 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1990 * and skb->cb are mangled. It works because (and until) packets
1991 * falling here are owned by current CPU. Output packets are cloned
1992 * by dev_queue_xmit_nit(), input packets are processed by net_bh
1993 * sequencially, so that if we return skb to original state on exit,
1994 * we will not harm anyone.
1997 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1998 struct packet_type *pt, struct net_device *orig_dev)
2001 struct sockaddr_ll *sll;
2002 struct packet_sock *po;
2003 u8 *skb_head = skb->data;
2004 int skb_len = skb->len;
2005 unsigned int snaplen, res;
2006 bool is_drop_n_account = false;
2008 if (skb->pkt_type == PACKET_LOOPBACK)
2011 sk = pt->af_packet_priv;
2014 if (!net_eq(dev_net(dev), sock_net(sk)))
2019 if (dev->header_ops) {
2020 /* The device has an explicit notion of ll header,
2021 * exported to higher levels.
2023 * Otherwise, the device hides details of its frame
2024 * structure, so that corresponding packet head is
2025 * never delivered to user.
2027 if (sk->sk_type != SOCK_DGRAM)
2028 skb_push(skb, skb->data - skb_mac_header(skb));
2029 else if (skb->pkt_type == PACKET_OUTGOING) {
2030 /* Special case: outgoing packets have ll header at head */
2031 skb_pull(skb, skb_network_offset(skb));
2037 res = run_filter(skb, sk, snaplen);
2039 goto drop_n_restore;
2043 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2046 if (skb_shared(skb)) {
2047 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2051 if (skb_head != skb->data) {
2052 skb->data = skb_head;
2059 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2061 sll = &PACKET_SKB_CB(skb)->sa.ll;
2062 sll->sll_hatype = dev->type;
2063 sll->sll_pkttype = skb->pkt_type;
2064 if (unlikely(po->origdev))
2065 sll->sll_ifindex = orig_dev->ifindex;
2067 sll->sll_ifindex = dev->ifindex;
2069 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2071 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2072 * Use their space for storing the original skb length.
2074 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2076 if (pskb_trim(skb, snaplen))
2079 skb_set_owner_r(skb, sk);
2083 /* drop conntrack reference */
2086 spin_lock(&sk->sk_receive_queue.lock);
2087 po->stats.stats1.tp_packets++;
2088 sock_skb_set_dropcount(sk, skb);
2089 __skb_queue_tail(&sk->sk_receive_queue, skb);
2090 spin_unlock(&sk->sk_receive_queue.lock);
2091 sk->sk_data_ready(sk);
2095 is_drop_n_account = true;
2096 spin_lock(&sk->sk_receive_queue.lock);
2097 po->stats.stats1.tp_drops++;
2098 atomic_inc(&sk->sk_drops);
2099 spin_unlock(&sk->sk_receive_queue.lock);
2102 if (skb_head != skb->data && skb_shared(skb)) {
2103 skb->data = skb_head;
2107 if (!is_drop_n_account)
2114 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2115 struct packet_type *pt, struct net_device *orig_dev)
2118 struct packet_sock *po;
2119 struct sockaddr_ll *sll;
2120 union tpacket_uhdr h;
2121 u8 *skb_head = skb->data;
2122 int skb_len = skb->len;
2123 unsigned int snaplen, res;
2124 unsigned long status = TP_STATUS_USER;
2125 unsigned short macoff, netoff, hdrlen;
2126 struct sk_buff *copy_skb = NULL;
2129 bool is_drop_n_account = false;
2131 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2132 * We may add members to them until current aligned size without forcing
2133 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2135 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2136 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2138 if (skb->pkt_type == PACKET_LOOPBACK)
2141 sk = pt->af_packet_priv;
2144 if (!net_eq(dev_net(dev), sock_net(sk)))
2147 if (dev->header_ops) {
2148 if (sk->sk_type != SOCK_DGRAM)
2149 skb_push(skb, skb->data - skb_mac_header(skb));
2150 else if (skb->pkt_type == PACKET_OUTGOING) {
2151 /* Special case: outgoing packets have ll header at head */
2152 skb_pull(skb, skb_network_offset(skb));
2158 res = run_filter(skb, sk, snaplen);
2160 goto drop_n_restore;
2162 if (skb->ip_summed == CHECKSUM_PARTIAL)
2163 status |= TP_STATUS_CSUMNOTREADY;
2164 else if (skb->pkt_type != PACKET_OUTGOING &&
2165 (skb->ip_summed == CHECKSUM_COMPLETE ||
2166 skb_csum_unnecessary(skb)))
2167 status |= TP_STATUS_CSUM_VALID;
2172 if (sk->sk_type == SOCK_DGRAM) {
2173 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2176 unsigned int maclen = skb_network_offset(skb);
2177 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2178 (maclen < 16 ? 16 : maclen)) +
2180 if (po->has_vnet_hdr)
2181 netoff += sizeof(struct virtio_net_hdr);
2182 macoff = netoff - maclen;
2184 if (po->tp_version <= TPACKET_V2) {
2185 if (macoff + snaplen > po->rx_ring.frame_size) {
2186 if (po->copy_thresh &&
2187 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2188 if (skb_shared(skb)) {
2189 copy_skb = skb_clone(skb, GFP_ATOMIC);
2191 copy_skb = skb_get(skb);
2192 skb_head = skb->data;
2195 skb_set_owner_r(copy_skb, sk);
2197 snaplen = po->rx_ring.frame_size - macoff;
2198 if ((int)snaplen < 0)
2201 } else if (unlikely(macoff + snaplen >
2202 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2205 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2206 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2207 snaplen, nval, macoff);
2209 if (unlikely((int)snaplen < 0)) {
2211 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2214 spin_lock(&sk->sk_receive_queue.lock);
2215 h.raw = packet_current_rx_frame(po, skb,
2216 TP_STATUS_KERNEL, (macoff+snaplen));
2218 goto drop_n_account;
2219 if (po->tp_version <= TPACKET_V2) {
2220 packet_increment_rx_head(po, &po->rx_ring);
2222 * LOSING will be reported till you read the stats,
2223 * because it's COR - Clear On Read.
2224 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2227 if (po->stats.stats1.tp_drops)
2228 status |= TP_STATUS_LOSING;
2230 po->stats.stats1.tp_packets++;
2232 status |= TP_STATUS_COPY;
2233 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2235 spin_unlock(&sk->sk_receive_queue.lock);
2237 if (po->has_vnet_hdr) {
2238 if (virtio_net_hdr_from_skb(skb, h.raw + macoff -
2239 sizeof(struct virtio_net_hdr),
2241 spin_lock(&sk->sk_receive_queue.lock);
2242 goto drop_n_account;
2246 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2248 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2249 getnstimeofday(&ts);
2251 status |= ts_status;
2253 switch (po->tp_version) {
2255 h.h1->tp_len = skb->len;
2256 h.h1->tp_snaplen = snaplen;
2257 h.h1->tp_mac = macoff;
2258 h.h1->tp_net = netoff;
2259 h.h1->tp_sec = ts.tv_sec;
2260 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2261 hdrlen = sizeof(*h.h1);
2264 h.h2->tp_len = skb->len;
2265 h.h2->tp_snaplen = snaplen;
2266 h.h2->tp_mac = macoff;
2267 h.h2->tp_net = netoff;
2268 h.h2->tp_sec = ts.tv_sec;
2269 h.h2->tp_nsec = ts.tv_nsec;
2270 if (skb_vlan_tag_present(skb)) {
2271 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2272 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2273 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2275 h.h2->tp_vlan_tci = 0;
2276 h.h2->tp_vlan_tpid = 0;
2278 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2279 hdrlen = sizeof(*h.h2);
2282 /* tp_nxt_offset,vlan are already populated above.
2283 * So DONT clear those fields here
2285 h.h3->tp_status |= status;
2286 h.h3->tp_len = skb->len;
2287 h.h3->tp_snaplen = snaplen;
2288 h.h3->tp_mac = macoff;
2289 h.h3->tp_net = netoff;
2290 h.h3->tp_sec = ts.tv_sec;
2291 h.h3->tp_nsec = ts.tv_nsec;
2292 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2293 hdrlen = sizeof(*h.h3);
2299 sll = h.raw + TPACKET_ALIGN(hdrlen);
2300 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2301 sll->sll_family = AF_PACKET;
2302 sll->sll_hatype = dev->type;
2303 sll->sll_protocol = skb->protocol;
2304 sll->sll_pkttype = skb->pkt_type;
2305 if (unlikely(po->origdev))
2306 sll->sll_ifindex = orig_dev->ifindex;
2308 sll->sll_ifindex = dev->ifindex;
2312 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2313 if (po->tp_version <= TPACKET_V2) {
2316 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2319 for (start = h.raw; start < end; start += PAGE_SIZE)
2320 flush_dcache_page(pgv_to_page(start));
2325 if (po->tp_version <= TPACKET_V2) {
2326 __packet_set_status(po, h.raw, status);
2327 sk->sk_data_ready(sk);
2329 prb_clear_blk_fill_status(&po->rx_ring);
2333 if (skb_head != skb->data && skb_shared(skb)) {
2334 skb->data = skb_head;
2338 if (!is_drop_n_account)
2345 is_drop_n_account = true;
2346 po->stats.stats1.tp_drops++;
2347 spin_unlock(&sk->sk_receive_queue.lock);
2349 sk->sk_data_ready(sk);
2350 kfree_skb(copy_skb);
2351 goto drop_n_restore;
2354 static void tpacket_destruct_skb(struct sk_buff *skb)
2356 struct packet_sock *po = pkt_sk(skb->sk);
2358 if (likely(po->tx_ring.pg_vec)) {
2362 ph = skb_shinfo(skb)->destructor_arg;
2363 packet_dec_pending(&po->tx_ring);
2365 ts = __packet_set_timestamp(po, ph, skb);
2366 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2372 static void tpacket_set_protocol(const struct net_device *dev,
2373 struct sk_buff *skb)
2375 if (dev->type == ARPHRD_ETHER) {
2376 skb_reset_mac_header(skb);
2377 skb->protocol = eth_hdr(skb)->h_proto;
2381 static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2383 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2384 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2385 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2386 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2387 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2388 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2389 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2391 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2397 static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2398 struct virtio_net_hdr *vnet_hdr)
2402 if (*len < sizeof(*vnet_hdr))
2404 *len -= sizeof(*vnet_hdr);
2406 n = copy_from_iter(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter);
2407 if (n != sizeof(*vnet_hdr))
2410 return __packet_snd_vnet_parse(vnet_hdr, *len);
2413 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2414 void *frame, struct net_device *dev, void *data, int tp_len,
2415 __be16 proto, unsigned char *addr, int hlen, int copylen,
2416 const struct sockcm_cookie *sockc)
2418 union tpacket_uhdr ph;
2419 int to_write, offset, len, nr_frags, len_max;
2420 struct socket *sock = po->sk.sk_socket;
2426 skb->protocol = proto;
2428 skb->priority = po->sk.sk_priority;
2429 skb->mark = po->sk.sk_mark;
2430 sock_tx_timestamp(&po->sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
2431 skb_shinfo(skb)->destructor_arg = ph.raw;
2433 skb_reserve(skb, hlen);
2434 skb_reset_network_header(skb);
2438 if (sock->type == SOCK_DGRAM) {
2439 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2441 if (unlikely(err < 0))
2443 } else if (copylen) {
2444 int hdrlen = min_t(int, copylen, tp_len);
2446 skb_push(skb, dev->hard_header_len);
2447 skb_put(skb, copylen - dev->hard_header_len);
2448 err = skb_store_bits(skb, 0, data, hdrlen);
2451 if (!dev_validate_header(dev, skb->data, hdrlen))
2454 tpacket_set_protocol(dev, skb);
2460 offset = offset_in_page(data);
2461 len_max = PAGE_SIZE - offset;
2462 len = ((to_write > len_max) ? len_max : to_write);
2464 skb->data_len = to_write;
2465 skb->len += to_write;
2466 skb->truesize += to_write;
2467 atomic_add(to_write, &po->sk.sk_wmem_alloc);
2469 while (likely(to_write)) {
2470 nr_frags = skb_shinfo(skb)->nr_frags;
2472 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2473 pr_err("Packet exceed the number of skb frags(%lu)\n",
2478 page = pgv_to_page(data);
2480 flush_dcache_page(page);
2482 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2485 len_max = PAGE_SIZE;
2486 len = ((to_write > len_max) ? len_max : to_write);
2489 skb_probe_transport_header(skb, 0);
2494 static int tpacket_parse_header(struct packet_sock *po, void *frame,
2495 int size_max, void **data)
2497 union tpacket_uhdr ph;
2502 switch (po->tp_version) {
2504 tp_len = ph.h2->tp_len;
2507 tp_len = ph.h1->tp_len;
2510 if (unlikely(tp_len > size_max)) {
2511 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2515 if (unlikely(po->tp_tx_has_off)) {
2516 int off_min, off_max;
2518 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2519 off_max = po->tx_ring.frame_size - tp_len;
2520 if (po->sk.sk_type == SOCK_DGRAM) {
2521 switch (po->tp_version) {
2523 off = ph.h2->tp_net;
2526 off = ph.h1->tp_net;
2530 switch (po->tp_version) {
2532 off = ph.h2->tp_mac;
2535 off = ph.h1->tp_mac;
2539 if (unlikely((off < off_min) || (off_max < off)))
2542 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2545 *data = frame + off;
2549 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2551 struct sk_buff *skb;
2552 struct net_device *dev;
2553 struct virtio_net_hdr *vnet_hdr = NULL;
2554 struct sockcm_cookie sockc;
2556 int err, reserve = 0;
2558 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2559 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2560 int tp_len, size_max;
2561 unsigned char *addr;
2564 int status = TP_STATUS_AVAILABLE;
2565 int hlen, tlen, copylen = 0;
2567 mutex_lock(&po->pg_vec_lock);
2569 if (likely(saddr == NULL)) {
2570 dev = packet_cached_dev_get(po);
2575 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2577 if (msg->msg_namelen < (saddr->sll_halen
2578 + offsetof(struct sockaddr_ll,
2581 proto = saddr->sll_protocol;
2582 addr = saddr->sll_addr;
2583 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2586 sockc.tsflags = po->sk.sk_tsflags;
2587 if (msg->msg_controllen) {
2588 err = sock_cmsg_send(&po->sk, msg, &sockc);
2594 if (unlikely(dev == NULL))
2597 if (unlikely(!(dev->flags & IFF_UP)))
2600 if (po->sk.sk_socket->type == SOCK_RAW)
2601 reserve = dev->hard_header_len;
2602 size_max = po->tx_ring.frame_size
2603 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2605 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2606 size_max = dev->mtu + reserve + VLAN_HLEN;
2609 ph = packet_current_frame(po, &po->tx_ring,
2610 TP_STATUS_SEND_REQUEST);
2611 if (unlikely(ph == NULL)) {
2612 if (need_wait && need_resched())
2618 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2622 status = TP_STATUS_SEND_REQUEST;
2623 hlen = LL_RESERVED_SPACE(dev);
2624 tlen = dev->needed_tailroom;
2625 if (po->has_vnet_hdr) {
2627 data += sizeof(*vnet_hdr);
2628 tp_len -= sizeof(*vnet_hdr);
2630 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2634 copylen = __virtio16_to_cpu(vio_le(),
2637 copylen = max_t(int, copylen, dev->hard_header_len);
2638 skb = sock_alloc_send_skb(&po->sk,
2639 hlen + tlen + sizeof(struct sockaddr_ll) +
2640 (copylen - dev->hard_header_len),
2643 if (unlikely(skb == NULL)) {
2644 /* we assume the socket was initially writeable ... */
2645 if (likely(len_sum > 0))
2649 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2650 addr, hlen, copylen, &sockc);
2651 if (likely(tp_len >= 0) &&
2652 tp_len > dev->mtu + reserve &&
2653 !po->has_vnet_hdr &&
2654 !packet_extra_vlan_len_allowed(dev, skb))
2657 if (unlikely(tp_len < 0)) {
2660 __packet_set_status(po, ph,
2661 TP_STATUS_AVAILABLE);
2662 packet_increment_head(&po->tx_ring);
2666 status = TP_STATUS_WRONG_FORMAT;
2672 if (po->has_vnet_hdr && virtio_net_hdr_to_skb(skb, vnet_hdr,
2678 packet_pick_tx_queue(dev, skb);
2680 skb->destructor = tpacket_destruct_skb;
2681 __packet_set_status(po, ph, TP_STATUS_SENDING);
2682 packet_inc_pending(&po->tx_ring);
2684 status = TP_STATUS_SEND_REQUEST;
2685 err = po->xmit(skb);
2686 if (unlikely(err > 0)) {
2687 err = net_xmit_errno(err);
2688 if (err && __packet_get_status(po, ph) ==
2689 TP_STATUS_AVAILABLE) {
2690 /* skb was destructed already */
2695 * skb was dropped but not destructed yet;
2696 * let's treat it like congestion or err < 0
2700 packet_increment_head(&po->tx_ring);
2702 } while (likely((ph != NULL) ||
2703 /* Note: packet_read_pending() might be slow if we have
2704 * to call it as it's per_cpu variable, but in fast-path
2705 * we already short-circuit the loop with the first
2706 * condition, and luckily don't have to go that path
2709 (need_wait && packet_read_pending(&po->tx_ring))));
2715 __packet_set_status(po, ph, status);
2720 mutex_unlock(&po->pg_vec_lock);
2724 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2725 size_t reserve, size_t len,
2726 size_t linear, int noblock,
2729 struct sk_buff *skb;
2731 /* Under a page? Don't bother with paged skb. */
2732 if (prepad + len < PAGE_SIZE || !linear)
2735 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2740 skb_reserve(skb, reserve);
2741 skb_put(skb, linear);
2742 skb->data_len = len - linear;
2743 skb->len += len - linear;
2748 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2750 struct sock *sk = sock->sk;
2751 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2752 struct sk_buff *skb;
2753 struct net_device *dev;
2755 unsigned char *addr;
2756 int err, reserve = 0;
2757 struct sockcm_cookie sockc;
2758 struct virtio_net_hdr vnet_hdr = { 0 };
2760 struct packet_sock *po = pkt_sk(sk);
2765 * Get and verify the address.
2768 if (likely(saddr == NULL)) {
2769 dev = packet_cached_dev_get(po);
2774 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2776 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2778 proto = saddr->sll_protocol;
2779 addr = saddr->sll_addr;
2780 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2784 if (unlikely(dev == NULL))
2787 if (unlikely(!(dev->flags & IFF_UP)))
2790 sockc.tsflags = sk->sk_tsflags;
2791 sockc.mark = sk->sk_mark;
2792 if (msg->msg_controllen) {
2793 err = sock_cmsg_send(sk, msg, &sockc);
2798 if (sock->type == SOCK_RAW)
2799 reserve = dev->hard_header_len;
2800 if (po->has_vnet_hdr) {
2801 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2806 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2807 if (!netif_supports_nofcs(dev)) {
2808 err = -EPROTONOSUPPORT;
2811 extra_len = 4; /* We're doing our own CRC */
2815 if (!vnet_hdr.gso_type &&
2816 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2820 hlen = LL_RESERVED_SPACE(dev);
2821 tlen = dev->needed_tailroom;
2822 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2823 __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len),
2824 msg->msg_flags & MSG_DONTWAIT, &err);
2828 skb_set_network_header(skb, reserve);
2831 if (sock->type == SOCK_DGRAM) {
2832 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2833 if (unlikely(offset < 0))
2837 /* Returns -EFAULT on error */
2838 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2842 if (sock->type == SOCK_RAW &&
2843 !dev_validate_header(dev, skb->data, len)) {
2848 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
2850 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2851 !packet_extra_vlan_len_allowed(dev, skb)) {
2856 skb->protocol = proto;
2858 skb->priority = sk->sk_priority;
2859 skb->mark = sockc.mark;
2861 packet_pick_tx_queue(dev, skb);
2863 if (po->has_vnet_hdr) {
2864 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
2867 len += sizeof(vnet_hdr);
2870 skb_probe_transport_header(skb, reserve);
2872 if (unlikely(extra_len == 4))
2875 err = po->xmit(skb);
2876 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2892 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2894 struct sock *sk = sock->sk;
2895 struct packet_sock *po = pkt_sk(sk);
2897 if (po->tx_ring.pg_vec)
2898 return tpacket_snd(po, msg);
2900 return packet_snd(sock, msg, len);
2904 * Close a PACKET socket. This is fairly simple. We immediately go
2905 * to 'closed' state and remove our protocol entry in the device list.
2908 static int packet_release(struct socket *sock)
2910 struct sock *sk = sock->sk;
2911 struct packet_sock *po;
2913 union tpacket_req_u req_u;
2921 mutex_lock(&net->packet.sklist_lock);
2922 sk_del_node_init_rcu(sk);
2923 mutex_unlock(&net->packet.sklist_lock);
2926 sock_prot_inuse_add(net, sk->sk_prot, -1);
2929 spin_lock(&po->bind_lock);
2930 unregister_prot_hook(sk, false);
2931 packet_cached_dev_reset(po);
2933 if (po->prot_hook.dev) {
2934 dev_put(po->prot_hook.dev);
2935 po->prot_hook.dev = NULL;
2937 spin_unlock(&po->bind_lock);
2939 packet_flush_mclist(sk);
2941 if (po->rx_ring.pg_vec) {
2942 memset(&req_u, 0, sizeof(req_u));
2943 packet_set_ring(sk, &req_u, 1, 0);
2946 if (po->tx_ring.pg_vec) {
2947 memset(&req_u, 0, sizeof(req_u));
2948 packet_set_ring(sk, &req_u, 1, 1);
2955 * Now the socket is dead. No more input will appear.
2962 skb_queue_purge(&sk->sk_receive_queue);
2963 packet_free_pending(po);
2964 sk_refcnt_debug_release(sk);
2971 * Attach a packet hook.
2974 static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
2977 struct packet_sock *po = pkt_sk(sk);
2978 struct net_device *dev_curr;
2981 struct net_device *dev = NULL;
2983 bool unlisted = false;
2989 spin_lock(&po->bind_lock);
2993 dev = dev_get_by_name_rcu(sock_net(sk), name);
2998 } else if (ifindex) {
2999 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3009 proto_curr = po->prot_hook.type;
3010 dev_curr = po->prot_hook.dev;
3012 need_rehook = proto_curr != proto || dev_curr != dev;
3017 __unregister_prot_hook(sk, true);
3019 dev_curr = po->prot_hook.dev;
3021 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3026 po->prot_hook.type = proto;
3028 if (unlikely(unlisted)) {
3030 po->prot_hook.dev = NULL;
3032 packet_cached_dev_reset(po);
3034 po->prot_hook.dev = dev;
3035 po->ifindex = dev ? dev->ifindex : 0;
3036 packet_cached_dev_assign(po, dev);
3042 if (proto == 0 || !need_rehook)
3045 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3046 register_prot_hook(sk);
3048 sk->sk_err = ENETDOWN;
3049 if (!sock_flag(sk, SOCK_DEAD))
3050 sk->sk_error_report(sk);
3055 spin_unlock(&po->bind_lock);
3061 * Bind a packet socket to a device
3064 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3067 struct sock *sk = sock->sk;
3074 if (addr_len != sizeof(struct sockaddr))
3076 strlcpy(name, uaddr->sa_data, sizeof(name));
3078 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3081 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3083 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3084 struct sock *sk = sock->sk;
3090 if (addr_len < sizeof(struct sockaddr_ll))
3092 if (sll->sll_family != AF_PACKET)
3095 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3096 sll->sll_protocol ? : pkt_sk(sk)->num);
3099 static struct proto packet_proto = {
3101 .owner = THIS_MODULE,
3102 .obj_size = sizeof(struct packet_sock),
3106 * Create a packet of type SOCK_PACKET.
3109 static int packet_create(struct net *net, struct socket *sock, int protocol,
3113 struct packet_sock *po;
3114 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3117 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3119 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3120 sock->type != SOCK_PACKET)
3121 return -ESOCKTNOSUPPORT;
3123 sock->state = SS_UNCONNECTED;
3126 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3130 sock->ops = &packet_ops;
3131 if (sock->type == SOCK_PACKET)
3132 sock->ops = &packet_ops_spkt;
3134 sock_init_data(sock, sk);
3137 sk->sk_family = PF_PACKET;
3139 po->xmit = dev_queue_xmit;
3141 err = packet_alloc_pending(po);
3145 packet_cached_dev_reset(po);
3147 sk->sk_destruct = packet_sock_destruct;
3148 sk_refcnt_debug_inc(sk);
3151 * Attach a protocol block
3154 spin_lock_init(&po->bind_lock);
3155 mutex_init(&po->pg_vec_lock);
3156 po->rollover = NULL;
3157 po->prot_hook.func = packet_rcv;
3159 if (sock->type == SOCK_PACKET)
3160 po->prot_hook.func = packet_rcv_spkt;
3162 po->prot_hook.af_packet_priv = sk;
3165 po->prot_hook.type = proto;
3166 register_prot_hook(sk);
3169 mutex_lock(&net->packet.sklist_lock);
3170 sk_add_node_rcu(sk, &net->packet.sklist);
3171 mutex_unlock(&net->packet.sklist_lock);
3174 sock_prot_inuse_add(net, &packet_proto, 1);
3185 * Pull a packet from our receive queue and hand it to the user.
3186 * If necessary we block.
3189 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3192 struct sock *sk = sock->sk;
3193 struct sk_buff *skb;
3195 int vnet_hdr_len = 0;
3196 unsigned int origlen = 0;
3199 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3203 /* What error should we return now? EUNATTACH? */
3204 if (pkt_sk(sk)->ifindex < 0)
3208 if (flags & MSG_ERRQUEUE) {
3209 err = sock_recv_errqueue(sk, msg, len,
3210 SOL_PACKET, PACKET_TX_TIMESTAMP);
3215 * Call the generic datagram receiver. This handles all sorts
3216 * of horrible races and re-entrancy so we can forget about it
3217 * in the protocol layers.
3219 * Now it will return ENETDOWN, if device have just gone down,
3220 * but then it will block.
3223 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3226 * An error occurred so return it. Because skb_recv_datagram()
3227 * handles the blocking we don't see and worry about blocking
3234 if (pkt_sk(sk)->pressure)
3235 packet_rcv_has_room(pkt_sk(sk), NULL);
3237 if (pkt_sk(sk)->has_vnet_hdr) {
3238 err = packet_rcv_vnet(msg, skb, &len);
3241 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3244 /* You lose any data beyond the buffer you gave. If it worries
3245 * a user program they can ask the device for its MTU
3251 msg->msg_flags |= MSG_TRUNC;
3254 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3258 if (sock->type != SOCK_PACKET) {
3259 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3261 /* Original length was stored in sockaddr_ll fields */
3262 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3263 sll->sll_family = AF_PACKET;
3264 sll->sll_protocol = skb->protocol;
3267 sock_recv_ts_and_drops(msg, sk, skb);
3269 if (msg->msg_name) {
3270 /* If the address length field is there to be filled
3271 * in, we fill it in now.
3273 if (sock->type == SOCK_PACKET) {
3274 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3275 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3277 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3279 msg->msg_namelen = sll->sll_halen +
3280 offsetof(struct sockaddr_ll, sll_addr);
3282 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3286 if (pkt_sk(sk)->auxdata) {
3287 struct tpacket_auxdata aux;
3289 aux.tp_status = TP_STATUS_USER;
3290 if (skb->ip_summed == CHECKSUM_PARTIAL)
3291 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3292 else if (skb->pkt_type != PACKET_OUTGOING &&
3293 (skb->ip_summed == CHECKSUM_COMPLETE ||
3294 skb_csum_unnecessary(skb)))
3295 aux.tp_status |= TP_STATUS_CSUM_VALID;
3297 aux.tp_len = origlen;
3298 aux.tp_snaplen = skb->len;
3300 aux.tp_net = skb_network_offset(skb);
3301 if (skb_vlan_tag_present(skb)) {
3302 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3303 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3304 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3306 aux.tp_vlan_tci = 0;
3307 aux.tp_vlan_tpid = 0;
3309 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3313 * Free or return the buffer as appropriate. Again this
3314 * hides all the races and re-entrancy issues from us.
3316 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3319 skb_free_datagram(sk, skb);
3324 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3325 int *uaddr_len, int peer)
3327 struct net_device *dev;
3328 struct sock *sk = sock->sk;
3333 uaddr->sa_family = AF_PACKET;
3334 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3336 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3338 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3340 *uaddr_len = sizeof(*uaddr);
3345 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3346 int *uaddr_len, int peer)
3348 struct net_device *dev;
3349 struct sock *sk = sock->sk;
3350 struct packet_sock *po = pkt_sk(sk);
3351 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3356 sll->sll_family = AF_PACKET;
3357 sll->sll_ifindex = po->ifindex;
3358 sll->sll_protocol = po->num;
3359 sll->sll_pkttype = 0;
3361 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3363 sll->sll_hatype = dev->type;
3364 sll->sll_halen = dev->addr_len;
3365 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3367 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3371 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3376 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3380 case PACKET_MR_MULTICAST:
3381 if (i->alen != dev->addr_len)
3384 return dev_mc_add(dev, i->addr);
3386 return dev_mc_del(dev, i->addr);
3388 case PACKET_MR_PROMISC:
3389 return dev_set_promiscuity(dev, what);
3390 case PACKET_MR_ALLMULTI:
3391 return dev_set_allmulti(dev, what);
3392 case PACKET_MR_UNICAST:
3393 if (i->alen != dev->addr_len)
3396 return dev_uc_add(dev, i->addr);
3398 return dev_uc_del(dev, i->addr);
3406 static void packet_dev_mclist_delete(struct net_device *dev,
3407 struct packet_mclist **mlp)
3409 struct packet_mclist *ml;
3411 while ((ml = *mlp) != NULL) {
3412 if (ml->ifindex == dev->ifindex) {
3413 packet_dev_mc(dev, ml, -1);
3421 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3423 struct packet_sock *po = pkt_sk(sk);
3424 struct packet_mclist *ml, *i;
3425 struct net_device *dev;
3431 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3436 if (mreq->mr_alen > dev->addr_len)
3440 i = kmalloc(sizeof(*i), GFP_KERNEL);
3445 for (ml = po->mclist; ml; ml = ml->next) {
3446 if (ml->ifindex == mreq->mr_ifindex &&
3447 ml->type == mreq->mr_type &&
3448 ml->alen == mreq->mr_alen &&
3449 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3451 /* Free the new element ... */
3457 i->type = mreq->mr_type;
3458 i->ifindex = mreq->mr_ifindex;
3459 i->alen = mreq->mr_alen;
3460 memcpy(i->addr, mreq->mr_address, i->alen);
3461 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3463 i->next = po->mclist;
3465 err = packet_dev_mc(dev, i, 1);
3467 po->mclist = i->next;
3476 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3478 struct packet_mclist *ml, **mlp;
3482 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3483 if (ml->ifindex == mreq->mr_ifindex &&
3484 ml->type == mreq->mr_type &&
3485 ml->alen == mreq->mr_alen &&
3486 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3487 if (--ml->count == 0) {
3488 struct net_device *dev;
3490 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3492 packet_dev_mc(dev, ml, -1);
3502 static void packet_flush_mclist(struct sock *sk)
3504 struct packet_sock *po = pkt_sk(sk);
3505 struct packet_mclist *ml;
3511 while ((ml = po->mclist) != NULL) {
3512 struct net_device *dev;
3514 po->mclist = ml->next;
3515 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3517 packet_dev_mc(dev, ml, -1);
3524 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3526 struct sock *sk = sock->sk;
3527 struct packet_sock *po = pkt_sk(sk);
3530 if (level != SOL_PACKET)
3531 return -ENOPROTOOPT;
3534 case PACKET_ADD_MEMBERSHIP:
3535 case PACKET_DROP_MEMBERSHIP:
3537 struct packet_mreq_max mreq;
3539 memset(&mreq, 0, sizeof(mreq));
3540 if (len < sizeof(struct packet_mreq))
3542 if (len > sizeof(mreq))
3544 if (copy_from_user(&mreq, optval, len))
3546 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3548 if (optname == PACKET_ADD_MEMBERSHIP)
3549 ret = packet_mc_add(sk, &mreq);
3551 ret = packet_mc_drop(sk, &mreq);
3555 case PACKET_RX_RING:
3556 case PACKET_TX_RING:
3558 union tpacket_req_u req_u;
3561 switch (po->tp_version) {
3564 len = sizeof(req_u.req);
3568 len = sizeof(req_u.req3);
3573 if (copy_from_user(&req_u.req, optval, len))
3575 return packet_set_ring(sk, &req_u, 0,
3576 optname == PACKET_TX_RING);
3578 case PACKET_COPY_THRESH:
3582 if (optlen != sizeof(val))
3584 if (copy_from_user(&val, optval, sizeof(val)))
3587 pkt_sk(sk)->copy_thresh = val;
3590 case PACKET_VERSION:
3594 if (optlen != sizeof(val))
3596 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3598 if (copy_from_user(&val, optval, sizeof(val)))
3604 po->tp_version = val;
3610 case PACKET_RESERVE:
3614 if (optlen != sizeof(val))
3616 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3618 if (copy_from_user(&val, optval, sizeof(val)))
3620 po->tp_reserve = val;
3627 if (optlen != sizeof(val))
3629 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3631 if (copy_from_user(&val, optval, sizeof(val)))
3633 po->tp_loss = !!val;
3636 case PACKET_AUXDATA:
3640 if (optlen < sizeof(val))
3642 if (copy_from_user(&val, optval, sizeof(val)))
3645 po->auxdata = !!val;
3648 case PACKET_ORIGDEV:
3652 if (optlen < sizeof(val))
3654 if (copy_from_user(&val, optval, sizeof(val)))
3657 po->origdev = !!val;
3660 case PACKET_VNET_HDR:
3664 if (sock->type != SOCK_RAW)
3666 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3668 if (optlen < sizeof(val))
3670 if (copy_from_user(&val, optval, sizeof(val)))
3673 po->has_vnet_hdr = !!val;
3676 case PACKET_TIMESTAMP:
3680 if (optlen != sizeof(val))
3682 if (copy_from_user(&val, optval, sizeof(val)))
3685 po->tp_tstamp = val;
3692 if (optlen != sizeof(val))
3694 if (copy_from_user(&val, optval, sizeof(val)))
3697 return fanout_add(sk, val & 0xffff, val >> 16);
3699 case PACKET_FANOUT_DATA:
3704 return fanout_set_data(po, optval, optlen);
3706 case PACKET_TX_HAS_OFF:
3710 if (optlen != sizeof(val))
3712 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3714 if (copy_from_user(&val, optval, sizeof(val)))
3716 po->tp_tx_has_off = !!val;
3719 case PACKET_QDISC_BYPASS:
3723 if (optlen != sizeof(val))
3725 if (copy_from_user(&val, optval, sizeof(val)))
3728 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3732 return -ENOPROTOOPT;
3736 static int packet_getsockopt(struct socket *sock, int level, int optname,
3737 char __user *optval, int __user *optlen)
3740 int val, lv = sizeof(val);
3741 struct sock *sk = sock->sk;
3742 struct packet_sock *po = pkt_sk(sk);
3744 union tpacket_stats_u st;
3745 struct tpacket_rollover_stats rstats;
3747 if (level != SOL_PACKET)
3748 return -ENOPROTOOPT;
3750 if (get_user(len, optlen))
3757 case PACKET_STATISTICS:
3758 spin_lock_bh(&sk->sk_receive_queue.lock);
3759 memcpy(&st, &po->stats, sizeof(st));
3760 memset(&po->stats, 0, sizeof(po->stats));
3761 spin_unlock_bh(&sk->sk_receive_queue.lock);
3763 if (po->tp_version == TPACKET_V3) {
3764 lv = sizeof(struct tpacket_stats_v3);
3765 st.stats3.tp_packets += st.stats3.tp_drops;
3768 lv = sizeof(struct tpacket_stats);
3769 st.stats1.tp_packets += st.stats1.tp_drops;
3774 case PACKET_AUXDATA:
3777 case PACKET_ORIGDEV:
3780 case PACKET_VNET_HDR:
3781 val = po->has_vnet_hdr;
3783 case PACKET_VERSION:
3784 val = po->tp_version;
3787 if (len > sizeof(int))
3789 if (copy_from_user(&val, optval, len))
3793 val = sizeof(struct tpacket_hdr);
3796 val = sizeof(struct tpacket2_hdr);
3799 val = sizeof(struct tpacket3_hdr);
3805 case PACKET_RESERVE:
3806 val = po->tp_reserve;
3811 case PACKET_TIMESTAMP:
3812 val = po->tp_tstamp;
3816 ((u32)po->fanout->id |
3817 ((u32)po->fanout->type << 16) |
3818 ((u32)po->fanout->flags << 24)) :
3821 case PACKET_ROLLOVER_STATS:
3824 rstats.tp_all = atomic_long_read(&po->rollover->num);
3825 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3826 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3828 lv = sizeof(rstats);
3830 case PACKET_TX_HAS_OFF:
3831 val = po->tp_tx_has_off;
3833 case PACKET_QDISC_BYPASS:
3834 val = packet_use_direct_xmit(po);
3837 return -ENOPROTOOPT;
3842 if (put_user(len, optlen))
3844 if (copy_to_user(optval, data, len))
3850 #ifdef CONFIG_COMPAT
3851 static int compat_packet_setsockopt(struct socket *sock, int level, int optname,
3852 char __user *optval, unsigned int optlen)
3854 struct packet_sock *po = pkt_sk(sock->sk);
3856 if (level != SOL_PACKET)
3857 return -ENOPROTOOPT;
3859 if (optname == PACKET_FANOUT_DATA &&
3860 po->fanout && po->fanout->type == PACKET_FANOUT_CBPF) {
3861 optval = (char __user *)get_compat_bpf_fprog(optval);
3864 optlen = sizeof(struct sock_fprog);
3867 return packet_setsockopt(sock, level, optname, optval, optlen);
3871 static int packet_notifier(struct notifier_block *this,
3872 unsigned long msg, void *ptr)
3875 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3876 struct net *net = dev_net(dev);
3879 sk_for_each_rcu(sk, &net->packet.sklist) {
3880 struct packet_sock *po = pkt_sk(sk);
3883 case NETDEV_UNREGISTER:
3885 packet_dev_mclist_delete(dev, &po->mclist);
3889 if (dev->ifindex == po->ifindex) {
3890 spin_lock(&po->bind_lock);
3892 __unregister_prot_hook(sk, false);
3893 sk->sk_err = ENETDOWN;
3894 if (!sock_flag(sk, SOCK_DEAD))
3895 sk->sk_error_report(sk);
3897 if (msg == NETDEV_UNREGISTER) {
3898 packet_cached_dev_reset(po);
3901 if (po->prot_hook.dev)
3902 dev_put(po->prot_hook.dev);
3903 po->prot_hook.dev = NULL;
3905 spin_unlock(&po->bind_lock);
3909 if (dev->ifindex == po->ifindex) {
3910 spin_lock(&po->bind_lock);
3912 register_prot_hook(sk);
3913 spin_unlock(&po->bind_lock);
3923 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3926 struct sock *sk = sock->sk;
3931 int amount = sk_wmem_alloc_get(sk);
3933 return put_user(amount, (int __user *)arg);
3937 struct sk_buff *skb;
3940 spin_lock_bh(&sk->sk_receive_queue.lock);
3941 skb = skb_peek(&sk->sk_receive_queue);
3944 spin_unlock_bh(&sk->sk_receive_queue.lock);
3945 return put_user(amount, (int __user *)arg);
3948 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3950 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3960 case SIOCGIFBRDADDR:
3961 case SIOCSIFBRDADDR:
3962 case SIOCGIFNETMASK:
3963 case SIOCSIFNETMASK:
3964 case SIOCGIFDSTADDR:
3965 case SIOCSIFDSTADDR:
3967 return inet_dgram_ops.ioctl(sock, cmd, arg);
3971 return -ENOIOCTLCMD;
3976 static unsigned int packet_poll(struct file *file, struct socket *sock,
3979 struct sock *sk = sock->sk;
3980 struct packet_sock *po = pkt_sk(sk);
3981 unsigned int mask = datagram_poll(file, sock, wait);
3983 spin_lock_bh(&sk->sk_receive_queue.lock);
3984 if (po->rx_ring.pg_vec) {
3985 if (!packet_previous_rx_frame(po, &po->rx_ring,
3987 mask |= POLLIN | POLLRDNORM;
3989 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
3991 spin_unlock_bh(&sk->sk_receive_queue.lock);
3992 spin_lock_bh(&sk->sk_write_queue.lock);
3993 if (po->tx_ring.pg_vec) {
3994 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3995 mask |= POLLOUT | POLLWRNORM;
3997 spin_unlock_bh(&sk->sk_write_queue.lock);
4002 /* Dirty? Well, I still did not learn better way to account
4006 static void packet_mm_open(struct vm_area_struct *vma)
4008 struct file *file = vma->vm_file;
4009 struct socket *sock = file->private_data;
4010 struct sock *sk = sock->sk;
4013 atomic_inc(&pkt_sk(sk)->mapped);
4016 static void packet_mm_close(struct vm_area_struct *vma)
4018 struct file *file = vma->vm_file;
4019 struct socket *sock = file->private_data;
4020 struct sock *sk = sock->sk;
4023 atomic_dec(&pkt_sk(sk)->mapped);
4026 static const struct vm_operations_struct packet_mmap_ops = {
4027 .open = packet_mm_open,
4028 .close = packet_mm_close,
4031 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4036 for (i = 0; i < len; i++) {
4037 if (likely(pg_vec[i].buffer)) {
4038 if (is_vmalloc_addr(pg_vec[i].buffer))
4039 vfree(pg_vec[i].buffer);
4041 free_pages((unsigned long)pg_vec[i].buffer,
4043 pg_vec[i].buffer = NULL;
4049 static char *alloc_one_pg_vec_page(unsigned long order)
4052 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4053 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4055 buffer = (char *) __get_free_pages(gfp_flags, order);
4059 /* __get_free_pages failed, fall back to vmalloc */
4060 buffer = vzalloc((1 << order) * PAGE_SIZE);
4064 /* vmalloc failed, lets dig into swap here */
4065 gfp_flags &= ~__GFP_NORETRY;
4066 buffer = (char *) __get_free_pages(gfp_flags, order);
4070 /* complete and utter failure */
4074 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4076 unsigned int block_nr = req->tp_block_nr;
4080 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4081 if (unlikely(!pg_vec))
4084 for (i = 0; i < block_nr; i++) {
4085 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4086 if (unlikely(!pg_vec[i].buffer))
4087 goto out_free_pgvec;
4094 free_pg_vec(pg_vec, order, block_nr);
4099 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4100 int closing, int tx_ring)
4102 struct pgv *pg_vec = NULL;
4103 struct packet_sock *po = pkt_sk(sk);
4104 int was_running, order = 0;
4105 struct packet_ring_buffer *rb;
4106 struct sk_buff_head *rb_queue;
4109 /* Added to avoid minimal code churn */
4110 struct tpacket_req *req = &req_u->req;
4112 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
4113 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
4114 net_warn_ratelimited("Tx-ring is not supported.\n");
4118 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4119 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4123 if (atomic_read(&po->mapped))
4125 if (packet_read_pending(rb))
4129 if (req->tp_block_nr) {
4130 /* Sanity tests and some calculations */
4132 if (unlikely(rb->pg_vec))
4135 switch (po->tp_version) {
4137 po->tp_hdrlen = TPACKET_HDRLEN;
4140 po->tp_hdrlen = TPACKET2_HDRLEN;
4143 po->tp_hdrlen = TPACKET3_HDRLEN;
4148 if (unlikely((int)req->tp_block_size <= 0))
4150 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4152 if (po->tp_version >= TPACKET_V3 &&
4153 (int)(req->tp_block_size -
4154 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
4156 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
4159 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4162 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4163 if (unlikely(rb->frames_per_block == 0))
4165 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4170 order = get_order(req->tp_block_size);
4171 pg_vec = alloc_pg_vec(req, order);
4172 if (unlikely(!pg_vec))
4174 switch (po->tp_version) {
4176 /* Transmit path is not supported. We checked
4177 * it above but just being paranoid
4180 init_prb_bdqc(po, rb, pg_vec, req_u);
4189 if (unlikely(req->tp_frame_nr))
4195 /* Detach socket from network */
4196 spin_lock(&po->bind_lock);
4197 was_running = po->running;
4201 __unregister_prot_hook(sk, false);
4203 spin_unlock(&po->bind_lock);
4208 mutex_lock(&po->pg_vec_lock);
4209 if (closing || atomic_read(&po->mapped) == 0) {
4211 spin_lock_bh(&rb_queue->lock);
4212 swap(rb->pg_vec, pg_vec);
4213 rb->frame_max = (req->tp_frame_nr - 1);
4215 rb->frame_size = req->tp_frame_size;
4216 spin_unlock_bh(&rb_queue->lock);
4218 swap(rb->pg_vec_order, order);
4219 swap(rb->pg_vec_len, req->tp_block_nr);
4221 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4222 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4223 tpacket_rcv : packet_rcv;
4224 skb_queue_purge(rb_queue);
4225 if (atomic_read(&po->mapped))
4226 pr_err("packet_mmap: vma is busy: %d\n",
4227 atomic_read(&po->mapped));
4229 mutex_unlock(&po->pg_vec_lock);
4231 spin_lock(&po->bind_lock);
4234 register_prot_hook(sk);
4236 spin_unlock(&po->bind_lock);
4237 if (closing && (po->tp_version > TPACKET_V2)) {
4238 /* Because we don't support block-based V3 on tx-ring */
4240 prb_shutdown_retire_blk_timer(po, rb_queue);
4245 free_pg_vec(pg_vec, order, req->tp_block_nr);
4250 static int packet_mmap(struct file *file, struct socket *sock,
4251 struct vm_area_struct *vma)
4253 struct sock *sk = sock->sk;
4254 struct packet_sock *po = pkt_sk(sk);
4255 unsigned long size, expected_size;
4256 struct packet_ring_buffer *rb;
4257 unsigned long start;
4264 mutex_lock(&po->pg_vec_lock);
4267 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4269 expected_size += rb->pg_vec_len
4275 if (expected_size == 0)
4278 size = vma->vm_end - vma->vm_start;
4279 if (size != expected_size)
4282 start = vma->vm_start;
4283 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4284 if (rb->pg_vec == NULL)
4287 for (i = 0; i < rb->pg_vec_len; i++) {
4289 void *kaddr = rb->pg_vec[i].buffer;
4292 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4293 page = pgv_to_page(kaddr);
4294 err = vm_insert_page(vma, start, page);
4303 atomic_inc(&po->mapped);
4304 vma->vm_ops = &packet_mmap_ops;
4308 mutex_unlock(&po->pg_vec_lock);
4312 static const struct proto_ops packet_ops_spkt = {
4313 .family = PF_PACKET,
4314 .owner = THIS_MODULE,
4315 .release = packet_release,
4316 .bind = packet_bind_spkt,
4317 .connect = sock_no_connect,
4318 .socketpair = sock_no_socketpair,
4319 .accept = sock_no_accept,
4320 .getname = packet_getname_spkt,
4321 .poll = datagram_poll,
4322 .ioctl = packet_ioctl,
4323 .listen = sock_no_listen,
4324 .shutdown = sock_no_shutdown,
4325 .setsockopt = sock_no_setsockopt,
4326 .getsockopt = sock_no_getsockopt,
4327 .sendmsg = packet_sendmsg_spkt,
4328 .recvmsg = packet_recvmsg,
4329 .mmap = sock_no_mmap,
4330 .sendpage = sock_no_sendpage,
4333 static const struct proto_ops packet_ops = {
4334 .family = PF_PACKET,
4335 .owner = THIS_MODULE,
4336 .release = packet_release,
4337 .bind = packet_bind,
4338 .connect = sock_no_connect,
4339 .socketpair = sock_no_socketpair,
4340 .accept = sock_no_accept,
4341 .getname = packet_getname,
4342 .poll = packet_poll,
4343 .ioctl = packet_ioctl,
4344 .listen = sock_no_listen,
4345 .shutdown = sock_no_shutdown,
4346 .setsockopt = packet_setsockopt,
4347 .getsockopt = packet_getsockopt,
4348 #ifdef CONFIG_COMPAT
4349 .compat_setsockopt = compat_packet_setsockopt,
4351 .sendmsg = packet_sendmsg,
4352 .recvmsg = packet_recvmsg,
4353 .mmap = packet_mmap,
4354 .sendpage = sock_no_sendpage,
4357 static const struct net_proto_family packet_family_ops = {
4358 .family = PF_PACKET,
4359 .create = packet_create,
4360 .owner = THIS_MODULE,
4363 static struct notifier_block packet_netdev_notifier = {
4364 .notifier_call = packet_notifier,
4367 #ifdef CONFIG_PROC_FS
4369 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4372 struct net *net = seq_file_net(seq);
4375 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4378 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4380 struct net *net = seq_file_net(seq);
4381 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4384 static void packet_seq_stop(struct seq_file *seq, void *v)
4390 static int packet_seq_show(struct seq_file *seq, void *v)
4392 if (v == SEQ_START_TOKEN)
4393 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4395 struct sock *s = sk_entry(v);
4396 const struct packet_sock *po = pkt_sk(s);
4399 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4401 atomic_read(&s->sk_refcnt),
4406 atomic_read(&s->sk_rmem_alloc),
4407 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4414 static const struct seq_operations packet_seq_ops = {
4415 .start = packet_seq_start,
4416 .next = packet_seq_next,
4417 .stop = packet_seq_stop,
4418 .show = packet_seq_show,
4421 static int packet_seq_open(struct inode *inode, struct file *file)
4423 return seq_open_net(inode, file, &packet_seq_ops,
4424 sizeof(struct seq_net_private));
4427 static const struct file_operations packet_seq_fops = {
4428 .owner = THIS_MODULE,
4429 .open = packet_seq_open,
4431 .llseek = seq_lseek,
4432 .release = seq_release_net,
4437 static int __net_init packet_net_init(struct net *net)
4439 mutex_init(&net->packet.sklist_lock);
4440 INIT_HLIST_HEAD(&net->packet.sklist);
4442 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4448 static void __net_exit packet_net_exit(struct net *net)
4450 remove_proc_entry("packet", net->proc_net);
4453 static struct pernet_operations packet_net_ops = {
4454 .init = packet_net_init,
4455 .exit = packet_net_exit,
4459 static void __exit packet_exit(void)
4461 unregister_netdevice_notifier(&packet_netdev_notifier);
4462 unregister_pernet_subsys(&packet_net_ops);
4463 sock_unregister(PF_PACKET);
4464 proto_unregister(&packet_proto);
4467 static int __init packet_init(void)
4469 int rc = proto_register(&packet_proto, 0);
4474 sock_register(&packet_family_ops);
4475 register_pernet_subsys(&packet_net_ops);
4476 register_netdevice_notifier(&packet_netdev_notifier);
4481 module_init(packet_init);
4482 module_exit(packet_exit);
4483 MODULE_LICENSE("GPL");
4484 MODULE_ALIAS_NETPROTO(PF_PACKET);