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 <linux/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 BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
181 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
182 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
183 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
184 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
185 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
186 #define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
189 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
190 struct packet_type *pt, struct net_device *orig_dev);
192 static void *packet_previous_frame(struct packet_sock *po,
193 struct packet_ring_buffer *rb,
195 static void packet_increment_head(struct packet_ring_buffer *buff);
196 static int prb_curr_blk_in_use(struct tpacket_block_desc *);
197 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
198 struct packet_sock *);
199 static void prb_retire_current_block(struct tpacket_kbdq_core *,
200 struct packet_sock *, unsigned int status);
201 static int prb_queue_frozen(struct tpacket_kbdq_core *);
202 static void prb_open_block(struct tpacket_kbdq_core *,
203 struct tpacket_block_desc *);
204 static void prb_retire_rx_blk_timer_expired(struct timer_list *);
205 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
206 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
207 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
208 struct tpacket3_hdr *);
209 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
210 struct tpacket3_hdr *);
211 static void packet_flush_mclist(struct sock *sk);
212 static u16 packet_pick_tx_queue(struct sk_buff *skb);
214 struct packet_skb_cb {
216 struct sockaddr_pkt pkt;
218 /* Trick: alias skb original length with
219 * ll.sll_family and ll.protocol in order
222 unsigned int origlen;
223 struct sockaddr_ll ll;
228 #define vio_le() virtio_legacy_is_little_endian()
230 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
232 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
233 #define GET_PBLOCK_DESC(x, bid) \
234 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
235 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
236 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
237 #define GET_NEXT_PRB_BLK_NUM(x) \
238 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
239 ((x)->kactive_blk_num+1) : 0)
241 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
242 static void __fanout_link(struct sock *sk, struct packet_sock *po);
244 static int packet_direct_xmit(struct sk_buff *skb)
246 return dev_direct_xmit(skb, packet_pick_tx_queue(skb));
249 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
251 struct net_device *dev;
254 dev = rcu_dereference(po->cached_dev);
262 static void packet_cached_dev_assign(struct packet_sock *po,
263 struct net_device *dev)
265 rcu_assign_pointer(po->cached_dev, dev);
268 static void packet_cached_dev_reset(struct packet_sock *po)
270 RCU_INIT_POINTER(po->cached_dev, NULL);
273 static bool packet_use_direct_xmit(const struct packet_sock *po)
275 return po->xmit == packet_direct_xmit;
278 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
280 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
283 static u16 packet_pick_tx_queue(struct sk_buff *skb)
285 struct net_device *dev = skb->dev;
286 const struct net_device_ops *ops = dev->netdev_ops;
289 if (ops->ndo_select_queue) {
290 queue_index = ops->ndo_select_queue(dev, skb, NULL,
291 __packet_pick_tx_queue);
292 queue_index = netdev_cap_txqueue(dev, queue_index);
294 queue_index = __packet_pick_tx_queue(dev, skb);
300 /* __register_prot_hook must be invoked through register_prot_hook
301 * or from a context in which asynchronous accesses to the packet
302 * socket is not possible (packet_create()).
304 static void __register_prot_hook(struct sock *sk)
306 struct packet_sock *po = pkt_sk(sk);
310 __fanout_link(sk, po);
312 dev_add_pack(&po->prot_hook);
319 static void register_prot_hook(struct sock *sk)
321 lockdep_assert_held_once(&pkt_sk(sk)->bind_lock);
322 __register_prot_hook(sk);
325 /* If the sync parameter is true, we will temporarily drop
326 * the po->bind_lock and do a synchronize_net to make sure no
327 * asynchronous packet processing paths still refer to the elements
328 * of po->prot_hook. If the sync parameter is false, it is the
329 * callers responsibility to take care of this.
331 static void __unregister_prot_hook(struct sock *sk, bool sync)
333 struct packet_sock *po = pkt_sk(sk);
335 lockdep_assert_held_once(&po->bind_lock);
340 __fanout_unlink(sk, po);
342 __dev_remove_pack(&po->prot_hook);
347 spin_unlock(&po->bind_lock);
349 spin_lock(&po->bind_lock);
353 static void unregister_prot_hook(struct sock *sk, bool sync)
355 struct packet_sock *po = pkt_sk(sk);
358 __unregister_prot_hook(sk, sync);
361 static inline struct page * __pure pgv_to_page(void *addr)
363 if (is_vmalloc_addr(addr))
364 return vmalloc_to_page(addr);
365 return virt_to_page(addr);
368 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
370 union tpacket_uhdr h;
373 switch (po->tp_version) {
375 h.h1->tp_status = status;
376 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
379 h.h2->tp_status = status;
380 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
383 h.h3->tp_status = status;
384 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
387 WARN(1, "TPACKET version not supported.\n");
394 static int __packet_get_status(struct packet_sock *po, void *frame)
396 union tpacket_uhdr h;
401 switch (po->tp_version) {
403 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
404 return h.h1->tp_status;
406 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
407 return h.h2->tp_status;
409 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
410 return h.h3->tp_status;
412 WARN(1, "TPACKET version not supported.\n");
418 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
421 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
424 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
425 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
426 return TP_STATUS_TS_RAW_HARDWARE;
428 if (ktime_to_timespec_cond(skb->tstamp, ts))
429 return TP_STATUS_TS_SOFTWARE;
434 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
437 union tpacket_uhdr h;
441 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
445 switch (po->tp_version) {
447 h.h1->tp_sec = ts.tv_sec;
448 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
451 h.h2->tp_sec = ts.tv_sec;
452 h.h2->tp_nsec = ts.tv_nsec;
455 h.h3->tp_sec = ts.tv_sec;
456 h.h3->tp_nsec = ts.tv_nsec;
459 WARN(1, "TPACKET version not supported.\n");
463 /* one flush is safe, as both fields always lie on the same cacheline */
464 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
470 static void *packet_lookup_frame(struct packet_sock *po,
471 struct packet_ring_buffer *rb,
472 unsigned int position,
475 unsigned int pg_vec_pos, frame_offset;
476 union tpacket_uhdr h;
478 pg_vec_pos = position / rb->frames_per_block;
479 frame_offset = position % rb->frames_per_block;
481 h.raw = rb->pg_vec[pg_vec_pos].buffer +
482 (frame_offset * rb->frame_size);
484 if (status != __packet_get_status(po, h.raw))
490 static void *packet_current_frame(struct packet_sock *po,
491 struct packet_ring_buffer *rb,
494 return packet_lookup_frame(po, rb, rb->head, status);
497 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
499 del_timer_sync(&pkc->retire_blk_timer);
502 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
503 struct sk_buff_head *rb_queue)
505 struct tpacket_kbdq_core *pkc;
507 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
509 spin_lock_bh(&rb_queue->lock);
510 pkc->delete_blk_timer = 1;
511 spin_unlock_bh(&rb_queue->lock);
513 prb_del_retire_blk_timer(pkc);
516 static void prb_setup_retire_blk_timer(struct packet_sock *po)
518 struct tpacket_kbdq_core *pkc;
520 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
521 timer_setup(&pkc->retire_blk_timer, prb_retire_rx_blk_timer_expired,
523 pkc->retire_blk_timer.expires = jiffies;
526 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
527 int blk_size_in_bytes)
529 struct net_device *dev;
530 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
531 struct ethtool_link_ksettings ecmd;
535 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
536 if (unlikely(!dev)) {
538 return DEFAULT_PRB_RETIRE_TOV;
540 err = __ethtool_get_link_ksettings(dev, &ecmd);
544 * If the link speed is so slow you don't really
545 * need to worry about perf anyways
547 if (ecmd.base.speed < SPEED_1000 ||
548 ecmd.base.speed == SPEED_UNKNOWN) {
549 return DEFAULT_PRB_RETIRE_TOV;
552 div = ecmd.base.speed / 1000;
556 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
568 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
569 union tpacket_req_u *req_u)
571 p1->feature_req_word = req_u->req3.tp_feature_req_word;
574 static void init_prb_bdqc(struct packet_sock *po,
575 struct packet_ring_buffer *rb,
577 union tpacket_req_u *req_u)
579 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
580 struct tpacket_block_desc *pbd;
582 memset(p1, 0x0, sizeof(*p1));
584 p1->knxt_seq_num = 1;
586 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
587 p1->pkblk_start = pg_vec[0].buffer;
588 p1->kblk_size = req_u->req3.tp_block_size;
589 p1->knum_blocks = req_u->req3.tp_block_nr;
590 p1->hdrlen = po->tp_hdrlen;
591 p1->version = po->tp_version;
592 p1->last_kactive_blk_num = 0;
593 po->stats.stats3.tp_freeze_q_cnt = 0;
594 if (req_u->req3.tp_retire_blk_tov)
595 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
597 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
598 req_u->req3.tp_block_size);
599 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
600 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
602 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
603 prb_init_ft_ops(p1, req_u);
604 prb_setup_retire_blk_timer(po);
605 prb_open_block(p1, pbd);
608 /* Do NOT update the last_blk_num first.
609 * Assumes sk_buff_head lock is held.
611 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
613 mod_timer(&pkc->retire_blk_timer,
614 jiffies + pkc->tov_in_jiffies);
615 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
620 * 1) We refresh the timer only when we open a block.
621 * By doing this we don't waste cycles refreshing the timer
622 * on packet-by-packet basis.
624 * With a 1MB block-size, on a 1Gbps line, it will take
625 * i) ~8 ms to fill a block + ii) memcpy etc.
626 * In this cut we are not accounting for the memcpy time.
628 * So, if the user sets the 'tmo' to 10ms then the timer
629 * will never fire while the block is still getting filled
630 * (which is what we want). However, the user could choose
631 * to close a block early and that's fine.
633 * But when the timer does fire, we check whether or not to refresh it.
634 * Since the tmo granularity is in msecs, it is not too expensive
635 * to refresh the timer, lets say every '8' msecs.
636 * Either the user can set the 'tmo' or we can derive it based on
637 * a) line-speed and b) block-size.
638 * prb_calc_retire_blk_tmo() calculates the tmo.
641 static void prb_retire_rx_blk_timer_expired(struct timer_list *t)
643 struct packet_sock *po =
644 from_timer(po, t, rx_ring.prb_bdqc.retire_blk_timer);
645 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
647 struct tpacket_block_desc *pbd;
649 spin_lock(&po->sk.sk_receive_queue.lock);
651 frozen = prb_queue_frozen(pkc);
652 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
654 if (unlikely(pkc->delete_blk_timer))
657 /* We only need to plug the race when the block is partially filled.
659 * lock(); increment BLOCK_NUM_PKTS; unlock()
660 * copy_bits() is in progress ...
661 * timer fires on other cpu:
662 * we can't retire the current block because copy_bits
666 if (BLOCK_NUM_PKTS(pbd)) {
667 while (atomic_read(&pkc->blk_fill_in_prog)) {
668 /* Waiting for skb_copy_bits to finish... */
673 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
675 if (!BLOCK_NUM_PKTS(pbd)) {
676 /* An empty block. Just refresh the timer. */
679 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
680 if (!prb_dispatch_next_block(pkc, po))
685 /* Case 1. Queue was frozen because user-space was
688 if (prb_curr_blk_in_use(pbd)) {
690 * Ok, user-space is still behind.
691 * So just refresh the timer.
695 /* Case 2. queue was frozen,user-space caught up,
696 * now the link went idle && the timer fired.
697 * We don't have a block to close.So we open this
698 * block and restart the timer.
699 * opening a block thaws the queue,restarts timer
700 * Thawing/timer-refresh is a side effect.
702 prb_open_block(pkc, pbd);
709 _prb_refresh_rx_retire_blk_timer(pkc);
712 spin_unlock(&po->sk.sk_receive_queue.lock);
715 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
716 struct tpacket_block_desc *pbd1, __u32 status)
718 /* Flush everything minus the block header */
720 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
725 /* Skip the block header(we know header WILL fit in 4K) */
728 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
729 for (; start < end; start += PAGE_SIZE)
730 flush_dcache_page(pgv_to_page(start));
735 /* Now update the block status. */
737 BLOCK_STATUS(pbd1) = status;
739 /* Flush the block header */
741 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
743 flush_dcache_page(pgv_to_page(start));
753 * 2) Increment active_blk_num
755 * Note:We DONT refresh the timer on purpose.
756 * Because almost always the next block will be opened.
758 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
759 struct tpacket_block_desc *pbd1,
760 struct packet_sock *po, unsigned int stat)
762 __u32 status = TP_STATUS_USER | stat;
764 struct tpacket3_hdr *last_pkt;
765 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
766 struct sock *sk = &po->sk;
768 if (po->stats.stats3.tp_drops)
769 status |= TP_STATUS_LOSING;
771 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
772 last_pkt->tp_next_offset = 0;
774 /* Get the ts of the last pkt */
775 if (BLOCK_NUM_PKTS(pbd1)) {
776 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
777 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
779 /* Ok, we tmo'd - so get the current time.
781 * It shouldn't really happen as we don't close empty
782 * blocks. See prb_retire_rx_blk_timer_expired().
786 h1->ts_last_pkt.ts_sec = ts.tv_sec;
787 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
792 /* Flush the block */
793 prb_flush_block(pkc1, pbd1, status);
795 sk->sk_data_ready(sk);
797 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
800 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
802 pkc->reset_pending_on_curr_blk = 0;
806 * Side effect of opening a block:
808 * 1) prb_queue is thawed.
809 * 2) retire_blk_timer is refreshed.
812 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
813 struct tpacket_block_desc *pbd1)
816 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
820 /* We could have just memset this but we will lose the
821 * flexibility of making the priv area sticky
824 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
825 BLOCK_NUM_PKTS(pbd1) = 0;
826 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
830 h1->ts_first_pkt.ts_sec = ts.tv_sec;
831 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
833 pkc1->pkblk_start = (char *)pbd1;
834 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
836 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
837 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
839 pbd1->version = pkc1->version;
840 pkc1->prev = pkc1->nxt_offset;
841 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
843 prb_thaw_queue(pkc1);
844 _prb_refresh_rx_retire_blk_timer(pkc1);
850 * Queue freeze logic:
851 * 1) Assume tp_block_nr = 8 blocks.
852 * 2) At time 't0', user opens Rx ring.
853 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
854 * 4) user-space is either sleeping or processing block '0'.
855 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
856 * it will close block-7,loop around and try to fill block '0'.
858 * __packet_lookup_frame_in_block
859 * prb_retire_current_block()
860 * prb_dispatch_next_block()
861 * |->(BLOCK_STATUS == USER) evaluates to true
862 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
863 * 6) Now there are two cases:
864 * 6.1) Link goes idle right after the queue is frozen.
865 * But remember, the last open_block() refreshed the timer.
866 * When this timer expires,it will refresh itself so that we can
867 * re-open block-0 in near future.
868 * 6.2) Link is busy and keeps on receiving packets. This is a simple
869 * case and __packet_lookup_frame_in_block will check if block-0
870 * is free and can now be re-used.
872 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
873 struct packet_sock *po)
875 pkc->reset_pending_on_curr_blk = 1;
876 po->stats.stats3.tp_freeze_q_cnt++;
879 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
882 * If the next block is free then we will dispatch it
883 * and return a good offset.
884 * Else, we will freeze the queue.
885 * So, caller must check the return value.
887 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
888 struct packet_sock *po)
890 struct tpacket_block_desc *pbd;
894 /* 1. Get current block num */
895 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
897 /* 2. If this block is currently in_use then freeze the queue */
898 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
899 prb_freeze_queue(pkc, po);
905 * open this block and return the offset where the first packet
906 * needs to get stored.
908 prb_open_block(pkc, pbd);
909 return (void *)pkc->nxt_offset;
912 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
913 struct packet_sock *po, unsigned int status)
915 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
917 /* retire/close the current block */
918 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
920 * Plug the case where copy_bits() is in progress on
921 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
922 * have space to copy the pkt in the current block and
923 * called prb_retire_current_block()
925 * We don't need to worry about the TMO case because
926 * the timer-handler already handled this case.
928 if (!(status & TP_STATUS_BLK_TMO)) {
929 while (atomic_read(&pkc->blk_fill_in_prog)) {
930 /* Waiting for skb_copy_bits to finish... */
934 prb_close_block(pkc, pbd, po, status);
939 static int prb_curr_blk_in_use(struct tpacket_block_desc *pbd)
941 return TP_STATUS_USER & BLOCK_STATUS(pbd);
944 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
946 return pkc->reset_pending_on_curr_blk;
949 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
951 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
952 atomic_dec(&pkc->blk_fill_in_prog);
955 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
956 struct tpacket3_hdr *ppd)
958 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
961 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
962 struct tpacket3_hdr *ppd)
964 ppd->hv1.tp_rxhash = 0;
967 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
968 struct tpacket3_hdr *ppd)
970 if (skb_vlan_tag_present(pkc->skb)) {
971 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
972 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
973 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
975 ppd->hv1.tp_vlan_tci = 0;
976 ppd->hv1.tp_vlan_tpid = 0;
977 ppd->tp_status = TP_STATUS_AVAILABLE;
981 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
982 struct tpacket3_hdr *ppd)
984 ppd->hv1.tp_padding = 0;
985 prb_fill_vlan_info(pkc, ppd);
987 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
988 prb_fill_rxhash(pkc, ppd);
990 prb_clear_rxhash(pkc, ppd);
993 static void prb_fill_curr_block(char *curr,
994 struct tpacket_kbdq_core *pkc,
995 struct tpacket_block_desc *pbd,
998 struct tpacket3_hdr *ppd;
1000 ppd = (struct tpacket3_hdr *)curr;
1001 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1003 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1004 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1005 BLOCK_NUM_PKTS(pbd) += 1;
1006 atomic_inc(&pkc->blk_fill_in_prog);
1007 prb_run_all_ft_ops(pkc, ppd);
1010 /* Assumes caller has the sk->rx_queue.lock */
1011 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1012 struct sk_buff *skb,
1017 struct tpacket_kbdq_core *pkc;
1018 struct tpacket_block_desc *pbd;
1021 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1022 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1024 /* Queue is frozen when user space is lagging behind */
1025 if (prb_queue_frozen(pkc)) {
1027 * Check if that last block which caused the queue to freeze,
1028 * is still in_use by user-space.
1030 if (prb_curr_blk_in_use(pbd)) {
1031 /* Can't record this packet */
1035 * Ok, the block was released by user-space.
1036 * Now let's open that block.
1037 * opening a block also thaws the queue.
1038 * Thawing is a side effect.
1040 prb_open_block(pkc, pbd);
1045 curr = pkc->nxt_offset;
1047 end = (char *)pbd + pkc->kblk_size;
1049 /* first try the current block */
1050 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1051 prb_fill_curr_block(curr, pkc, pbd, len);
1052 return (void *)curr;
1055 /* Ok, close the current block */
1056 prb_retire_current_block(pkc, po, 0);
1058 /* Now, try to dispatch the next block */
1059 curr = (char *)prb_dispatch_next_block(pkc, po);
1061 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1062 prb_fill_curr_block(curr, pkc, pbd, len);
1063 return (void *)curr;
1067 * No free blocks are available.user_space hasn't caught up yet.
1068 * Queue was just frozen and now this packet will get dropped.
1073 static void *packet_current_rx_frame(struct packet_sock *po,
1074 struct sk_buff *skb,
1075 int status, unsigned int len)
1078 switch (po->tp_version) {
1081 curr = packet_lookup_frame(po, &po->rx_ring,
1082 po->rx_ring.head, status);
1085 return __packet_lookup_frame_in_block(po, skb, status, len);
1087 WARN(1, "TPACKET version not supported\n");
1093 static void *prb_lookup_block(struct packet_sock *po,
1094 struct packet_ring_buffer *rb,
1098 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1099 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1101 if (status != BLOCK_STATUS(pbd))
1106 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1109 if (rb->prb_bdqc.kactive_blk_num)
1110 prev = rb->prb_bdqc.kactive_blk_num-1;
1112 prev = rb->prb_bdqc.knum_blocks-1;
1116 /* Assumes caller has held the rx_queue.lock */
1117 static void *__prb_previous_block(struct packet_sock *po,
1118 struct packet_ring_buffer *rb,
1121 unsigned int previous = prb_previous_blk_num(rb);
1122 return prb_lookup_block(po, rb, previous, status);
1125 static void *packet_previous_rx_frame(struct packet_sock *po,
1126 struct packet_ring_buffer *rb,
1129 if (po->tp_version <= TPACKET_V2)
1130 return packet_previous_frame(po, rb, status);
1132 return __prb_previous_block(po, rb, status);
1135 static void packet_increment_rx_head(struct packet_sock *po,
1136 struct packet_ring_buffer *rb)
1138 switch (po->tp_version) {
1141 return packet_increment_head(rb);
1144 WARN(1, "TPACKET version not supported.\n");
1150 static void *packet_previous_frame(struct packet_sock *po,
1151 struct packet_ring_buffer *rb,
1154 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1155 return packet_lookup_frame(po, rb, previous, status);
1158 static void packet_increment_head(struct packet_ring_buffer *buff)
1160 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1163 static void packet_inc_pending(struct packet_ring_buffer *rb)
1165 this_cpu_inc(*rb->pending_refcnt);
1168 static void packet_dec_pending(struct packet_ring_buffer *rb)
1170 this_cpu_dec(*rb->pending_refcnt);
1173 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1175 unsigned int refcnt = 0;
1178 /* We don't use pending refcount in rx_ring. */
1179 if (rb->pending_refcnt == NULL)
1182 for_each_possible_cpu(cpu)
1183 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1188 static int packet_alloc_pending(struct packet_sock *po)
1190 po->rx_ring.pending_refcnt = NULL;
1192 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1193 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1199 static void packet_free_pending(struct packet_sock *po)
1201 free_percpu(po->tx_ring.pending_refcnt);
1204 #define ROOM_POW_OFF 2
1205 #define ROOM_NONE 0x0
1206 #define ROOM_LOW 0x1
1207 #define ROOM_NORMAL 0x2
1209 static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1213 len = po->rx_ring.frame_max + 1;
1214 idx = po->rx_ring.head;
1216 idx += len >> pow_off;
1219 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1222 static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1226 len = po->rx_ring.prb_bdqc.knum_blocks;
1227 idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1229 idx += len >> pow_off;
1232 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1235 static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1237 struct sock *sk = &po->sk;
1238 int ret = ROOM_NONE;
1240 if (po->prot_hook.func != tpacket_rcv) {
1241 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1242 - (skb ? skb->truesize : 0);
1243 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1251 if (po->tp_version == TPACKET_V3) {
1252 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1254 else if (__tpacket_v3_has_room(po, 0))
1257 if (__tpacket_has_room(po, ROOM_POW_OFF))
1259 else if (__tpacket_has_room(po, 0))
1266 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1271 spin_lock_bh(&po->sk.sk_receive_queue.lock);
1272 ret = __packet_rcv_has_room(po, skb);
1273 has_room = ret == ROOM_NORMAL;
1274 if (po->pressure == has_room)
1275 po->pressure = !has_room;
1276 spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1281 static void packet_sock_destruct(struct sock *sk)
1283 skb_queue_purge(&sk->sk_error_queue);
1285 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1286 WARN_ON(refcount_read(&sk->sk_wmem_alloc));
1288 if (!sock_flag(sk, SOCK_DEAD)) {
1289 pr_err("Attempt to release alive packet socket: %p\n", sk);
1293 sk_refcnt_debug_dec(sk);
1296 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1301 rxhash = skb_get_hash(skb);
1302 for (i = 0; i < ROLLOVER_HLEN; i++)
1303 if (po->rollover->history[i] == rxhash)
1306 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
1307 return count > (ROLLOVER_HLEN >> 1);
1310 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1311 struct sk_buff *skb,
1314 return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1317 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1318 struct sk_buff *skb,
1321 unsigned int val = atomic_inc_return(&f->rr_cur);
1326 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1327 struct sk_buff *skb,
1330 return smp_processor_id() % num;
1333 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1334 struct sk_buff *skb,
1337 return prandom_u32_max(num);
1340 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1341 struct sk_buff *skb,
1342 unsigned int idx, bool try_self,
1345 struct packet_sock *po, *po_next, *po_skip = NULL;
1346 unsigned int i, j, room = ROOM_NONE;
1348 po = pkt_sk(f->arr[idx]);
1351 room = packet_rcv_has_room(po, skb);
1352 if (room == ROOM_NORMAL ||
1353 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1358 i = j = min_t(int, po->rollover->sock, num - 1);
1360 po_next = pkt_sk(f->arr[i]);
1361 if (po_next != po_skip && !po_next->pressure &&
1362 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1364 po->rollover->sock = i;
1365 atomic_long_inc(&po->rollover->num);
1366 if (room == ROOM_LOW)
1367 atomic_long_inc(&po->rollover->num_huge);
1375 atomic_long_inc(&po->rollover->num_failed);
1379 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1380 struct sk_buff *skb,
1383 return skb_get_queue_mapping(skb) % num;
1386 static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1387 struct sk_buff *skb,
1390 struct bpf_prog *prog;
1391 unsigned int ret = 0;
1394 prog = rcu_dereference(f->bpf_prog);
1396 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1402 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1404 return f->flags & (flag >> 8);
1407 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1408 struct packet_type *pt, struct net_device *orig_dev)
1410 struct packet_fanout *f = pt->af_packet_priv;
1411 unsigned int num = READ_ONCE(f->num_members);
1412 struct net *net = read_pnet(&f->net);
1413 struct packet_sock *po;
1416 if (!net_eq(dev_net(dev), net) || !num) {
1421 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1422 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1427 case PACKET_FANOUT_HASH:
1429 idx = fanout_demux_hash(f, skb, num);
1431 case PACKET_FANOUT_LB:
1432 idx = fanout_demux_lb(f, skb, num);
1434 case PACKET_FANOUT_CPU:
1435 idx = fanout_demux_cpu(f, skb, num);
1437 case PACKET_FANOUT_RND:
1438 idx = fanout_demux_rnd(f, skb, num);
1440 case PACKET_FANOUT_QM:
1441 idx = fanout_demux_qm(f, skb, num);
1443 case PACKET_FANOUT_ROLLOVER:
1444 idx = fanout_demux_rollover(f, skb, 0, false, num);
1446 case PACKET_FANOUT_CBPF:
1447 case PACKET_FANOUT_EBPF:
1448 idx = fanout_demux_bpf(f, skb, num);
1452 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1453 idx = fanout_demux_rollover(f, skb, idx, true, num);
1455 po = pkt_sk(f->arr[idx]);
1456 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1459 DEFINE_MUTEX(fanout_mutex);
1460 EXPORT_SYMBOL_GPL(fanout_mutex);
1461 static LIST_HEAD(fanout_list);
1462 static u16 fanout_next_id;
1464 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1466 struct packet_fanout *f = po->fanout;
1468 spin_lock(&f->lock);
1469 f->arr[f->num_members] = sk;
1472 if (f->num_members == 1)
1473 dev_add_pack(&f->prot_hook);
1474 spin_unlock(&f->lock);
1477 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1479 struct packet_fanout *f = po->fanout;
1482 spin_lock(&f->lock);
1483 for (i = 0; i < f->num_members; i++) {
1484 if (f->arr[i] == sk)
1487 BUG_ON(i >= f->num_members);
1488 f->arr[i] = f->arr[f->num_members - 1];
1490 if (f->num_members == 0)
1491 __dev_remove_pack(&f->prot_hook);
1492 spin_unlock(&f->lock);
1495 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1497 if (sk->sk_family != PF_PACKET)
1500 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1503 static void fanout_init_data(struct packet_fanout *f)
1506 case PACKET_FANOUT_LB:
1507 atomic_set(&f->rr_cur, 0);
1509 case PACKET_FANOUT_CBPF:
1510 case PACKET_FANOUT_EBPF:
1511 RCU_INIT_POINTER(f->bpf_prog, NULL);
1516 static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1518 struct bpf_prog *old;
1520 spin_lock(&f->lock);
1521 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1522 rcu_assign_pointer(f->bpf_prog, new);
1523 spin_unlock(&f->lock);
1527 bpf_prog_destroy(old);
1531 static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1534 struct bpf_prog *new;
1535 struct sock_fprog fprog;
1538 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1540 if (len != sizeof(fprog))
1542 if (copy_from_user(&fprog, data, len))
1545 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1549 __fanout_set_data_bpf(po->fanout, new);
1553 static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1556 struct bpf_prog *new;
1559 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1561 if (len != sizeof(fd))
1563 if (copy_from_user(&fd, data, len))
1566 new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1568 return PTR_ERR(new);
1570 __fanout_set_data_bpf(po->fanout, new);
1574 static int fanout_set_data(struct packet_sock *po, char __user *data,
1577 switch (po->fanout->type) {
1578 case PACKET_FANOUT_CBPF:
1579 return fanout_set_data_cbpf(po, data, len);
1580 case PACKET_FANOUT_EBPF:
1581 return fanout_set_data_ebpf(po, data, len);
1587 static void fanout_release_data(struct packet_fanout *f)
1590 case PACKET_FANOUT_CBPF:
1591 case PACKET_FANOUT_EBPF:
1592 __fanout_set_data_bpf(f, NULL);
1596 static bool __fanout_id_is_free(struct sock *sk, u16 candidate_id)
1598 struct packet_fanout *f;
1600 list_for_each_entry(f, &fanout_list, list) {
1601 if (f->id == candidate_id &&
1602 read_pnet(&f->net) == sock_net(sk)) {
1609 static bool fanout_find_new_id(struct sock *sk, u16 *new_id)
1611 u16 id = fanout_next_id;
1614 if (__fanout_id_is_free(sk, id)) {
1616 fanout_next_id = id + 1;
1621 } while (id != fanout_next_id);
1626 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1628 struct packet_rollover *rollover = NULL;
1629 struct packet_sock *po = pkt_sk(sk);
1630 struct packet_fanout *f, *match;
1631 u8 type = type_flags & 0xff;
1632 u8 flags = type_flags >> 8;
1636 case PACKET_FANOUT_ROLLOVER:
1637 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1639 case PACKET_FANOUT_HASH:
1640 case PACKET_FANOUT_LB:
1641 case PACKET_FANOUT_CPU:
1642 case PACKET_FANOUT_RND:
1643 case PACKET_FANOUT_QM:
1644 case PACKET_FANOUT_CBPF:
1645 case PACKET_FANOUT_EBPF:
1651 mutex_lock(&fanout_mutex);
1657 if (type == PACKET_FANOUT_ROLLOVER ||
1658 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1660 rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
1663 atomic_long_set(&rollover->num, 0);
1664 atomic_long_set(&rollover->num_huge, 0);
1665 atomic_long_set(&rollover->num_failed, 0);
1668 if (type_flags & PACKET_FANOUT_FLAG_UNIQUEID) {
1673 if (!fanout_find_new_id(sk, &id)) {
1677 /* ephemeral flag for the first socket in the group: drop it */
1678 flags &= ~(PACKET_FANOUT_FLAG_UNIQUEID >> 8);
1682 list_for_each_entry(f, &fanout_list, list) {
1684 read_pnet(&f->net) == sock_net(sk)) {
1690 if (match && match->flags != flags)
1694 match = kzalloc(sizeof(*match), GFP_KERNEL);
1697 write_pnet(&match->net, sock_net(sk));
1700 match->flags = flags;
1701 INIT_LIST_HEAD(&match->list);
1702 spin_lock_init(&match->lock);
1703 refcount_set(&match->sk_ref, 0);
1704 fanout_init_data(match);
1705 match->prot_hook.type = po->prot_hook.type;
1706 match->prot_hook.dev = po->prot_hook.dev;
1707 match->prot_hook.func = packet_rcv_fanout;
1708 match->prot_hook.af_packet_priv = match;
1709 match->prot_hook.id_match = match_fanout_group;
1710 list_add(&match->list, &fanout_list);
1714 spin_lock(&po->bind_lock);
1716 match->type == type &&
1717 match->prot_hook.type == po->prot_hook.type &&
1718 match->prot_hook.dev == po->prot_hook.dev) {
1720 if (refcount_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1721 __dev_remove_pack(&po->prot_hook);
1723 po->rollover = rollover;
1725 refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
1726 __fanout_link(sk, po);
1730 spin_unlock(&po->bind_lock);
1732 if (err && !refcount_read(&match->sk_ref)) {
1733 list_del(&match->list);
1739 mutex_unlock(&fanout_mutex);
1743 /* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
1744 * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
1745 * It is the responsibility of the caller to call fanout_release_data() and
1746 * free the returned packet_fanout (after synchronize_net())
1748 static struct packet_fanout *fanout_release(struct sock *sk)
1750 struct packet_sock *po = pkt_sk(sk);
1751 struct packet_fanout *f;
1753 mutex_lock(&fanout_mutex);
1758 if (refcount_dec_and_test(&f->sk_ref))
1763 mutex_unlock(&fanout_mutex);
1768 static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1769 struct sk_buff *skb)
1771 /* Earlier code assumed this would be a VLAN pkt, double-check
1772 * this now that we have the actual packet in hand. We can only
1773 * do this check on Ethernet devices.
1775 if (unlikely(dev->type != ARPHRD_ETHER))
1778 skb_reset_mac_header(skb);
1779 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1782 static const struct proto_ops packet_ops;
1784 static const struct proto_ops packet_ops_spkt;
1786 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1787 struct packet_type *pt, struct net_device *orig_dev)
1790 struct sockaddr_pkt *spkt;
1793 * When we registered the protocol we saved the socket in the data
1794 * field for just this event.
1797 sk = pt->af_packet_priv;
1800 * Yank back the headers [hope the device set this
1801 * right or kerboom...]
1803 * Incoming packets have ll header pulled,
1806 * For outgoing ones skb->data == skb_mac_header(skb)
1807 * so that this procedure is noop.
1810 if (skb->pkt_type == PACKET_LOOPBACK)
1813 if (!net_eq(dev_net(dev), sock_net(sk)))
1816 skb = skb_share_check(skb, GFP_ATOMIC);
1820 /* drop any routing info */
1823 /* drop conntrack reference */
1826 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1828 skb_push(skb, skb->data - skb_mac_header(skb));
1831 * The SOCK_PACKET socket receives _all_ frames.
1834 spkt->spkt_family = dev->type;
1835 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1836 spkt->spkt_protocol = skb->protocol;
1839 * Charge the memory to the socket. This is done specifically
1840 * to prevent sockets using all the memory up.
1843 if (sock_queue_rcv_skb(sk, skb) == 0)
1854 * Output a raw packet to a device layer. This bypasses all the other
1855 * protocol layers and you must therefore supply it with a complete frame
1858 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1861 struct sock *sk = sock->sk;
1862 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1863 struct sk_buff *skb = NULL;
1864 struct net_device *dev;
1865 struct sockcm_cookie sockc;
1871 * Get and verify the address.
1875 if (msg->msg_namelen < sizeof(struct sockaddr))
1877 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1878 proto = saddr->spkt_protocol;
1880 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1883 * Find the device first to size check it
1886 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1889 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1895 if (!(dev->flags & IFF_UP))
1899 * You may not queue a frame bigger than the mtu. This is the lowest level
1900 * raw protocol and you must do your own fragmentation at this level.
1903 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1904 if (!netif_supports_nofcs(dev)) {
1905 err = -EPROTONOSUPPORT;
1908 extra_len = 4; /* We're doing our own CRC */
1912 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1916 size_t reserved = LL_RESERVED_SPACE(dev);
1917 int tlen = dev->needed_tailroom;
1918 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1921 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1924 /* FIXME: Save some space for broken drivers that write a hard
1925 * header at transmission time by themselves. PPP is the notable
1926 * one here. This should really be fixed at the driver level.
1928 skb_reserve(skb, reserved);
1929 skb_reset_network_header(skb);
1931 /* Try to align data part correctly */
1936 skb_reset_network_header(skb);
1938 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1944 if (!dev_validate_header(dev, skb->data, len)) {
1948 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
1949 !packet_extra_vlan_len_allowed(dev, skb)) {
1954 sockc.tsflags = sk->sk_tsflags;
1955 if (msg->msg_controllen) {
1956 err = sock_cmsg_send(sk, msg, &sockc);
1961 skb->protocol = proto;
1963 skb->priority = sk->sk_priority;
1964 skb->mark = sk->sk_mark;
1966 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
1968 if (unlikely(extra_len == 4))
1971 skb_probe_transport_header(skb, 0);
1973 dev_queue_xmit(skb);
1984 static unsigned int run_filter(struct sk_buff *skb,
1985 const struct sock *sk,
1988 struct sk_filter *filter;
1991 filter = rcu_dereference(sk->sk_filter);
1993 res = bpf_prog_run_clear_cb(filter->prog, skb);
1999 static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2002 struct virtio_net_hdr vnet_hdr;
2004 if (*len < sizeof(vnet_hdr))
2006 *len -= sizeof(vnet_hdr);
2008 if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le(), true, 0))
2011 return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
2015 * This function makes lazy skb cloning in hope that most of packets
2016 * are discarded by BPF.
2018 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2019 * and skb->cb are mangled. It works because (and until) packets
2020 * falling here are owned by current CPU. Output packets are cloned
2021 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2022 * sequencially, so that if we return skb to original state on exit,
2023 * we will not harm anyone.
2026 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2027 struct packet_type *pt, struct net_device *orig_dev)
2030 struct sockaddr_ll *sll;
2031 struct packet_sock *po;
2032 u8 *skb_head = skb->data;
2033 int skb_len = skb->len;
2034 unsigned int snaplen, res;
2035 bool is_drop_n_account = false;
2037 if (skb->pkt_type == PACKET_LOOPBACK)
2040 sk = pt->af_packet_priv;
2043 if (!net_eq(dev_net(dev), sock_net(sk)))
2048 if (dev->header_ops) {
2049 /* The device has an explicit notion of ll header,
2050 * exported to higher levels.
2052 * Otherwise, the device hides details of its frame
2053 * structure, so that corresponding packet head is
2054 * never delivered to user.
2056 if (sk->sk_type != SOCK_DGRAM)
2057 skb_push(skb, skb->data - skb_mac_header(skb));
2058 else if (skb->pkt_type == PACKET_OUTGOING) {
2059 /* Special case: outgoing packets have ll header at head */
2060 skb_pull(skb, skb_network_offset(skb));
2066 res = run_filter(skb, sk, snaplen);
2068 goto drop_n_restore;
2072 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2075 if (skb_shared(skb)) {
2076 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2080 if (skb_head != skb->data) {
2081 skb->data = skb_head;
2088 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2090 sll = &PACKET_SKB_CB(skb)->sa.ll;
2091 sll->sll_hatype = dev->type;
2092 sll->sll_pkttype = skb->pkt_type;
2093 if (unlikely(po->origdev))
2094 sll->sll_ifindex = orig_dev->ifindex;
2096 sll->sll_ifindex = dev->ifindex;
2098 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2100 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2101 * Use their space for storing the original skb length.
2103 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2105 if (pskb_trim(skb, snaplen))
2108 skb_set_owner_r(skb, sk);
2112 /* drop conntrack reference */
2115 spin_lock(&sk->sk_receive_queue.lock);
2116 po->stats.stats1.tp_packets++;
2117 sock_skb_set_dropcount(sk, skb);
2118 __skb_queue_tail(&sk->sk_receive_queue, skb);
2119 spin_unlock(&sk->sk_receive_queue.lock);
2120 sk->sk_data_ready(sk);
2124 is_drop_n_account = true;
2125 spin_lock(&sk->sk_receive_queue.lock);
2126 po->stats.stats1.tp_drops++;
2127 atomic_inc(&sk->sk_drops);
2128 spin_unlock(&sk->sk_receive_queue.lock);
2131 if (skb_head != skb->data && skb_shared(skb)) {
2132 skb->data = skb_head;
2136 if (!is_drop_n_account)
2143 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2144 struct packet_type *pt, struct net_device *orig_dev)
2147 struct packet_sock *po;
2148 struct sockaddr_ll *sll;
2149 union tpacket_uhdr h;
2150 u8 *skb_head = skb->data;
2151 int skb_len = skb->len;
2152 unsigned int snaplen, res;
2153 unsigned long status = TP_STATUS_USER;
2154 unsigned short macoff, netoff, hdrlen;
2155 struct sk_buff *copy_skb = NULL;
2158 bool is_drop_n_account = false;
2159 bool do_vnet = false;
2161 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2162 * We may add members to them until current aligned size without forcing
2163 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2165 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2166 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2168 if (skb->pkt_type == PACKET_LOOPBACK)
2171 sk = pt->af_packet_priv;
2174 if (!net_eq(dev_net(dev), sock_net(sk)))
2177 if (dev->header_ops) {
2178 if (sk->sk_type != SOCK_DGRAM)
2179 skb_push(skb, skb->data - skb_mac_header(skb));
2180 else if (skb->pkt_type == PACKET_OUTGOING) {
2181 /* Special case: outgoing packets have ll header at head */
2182 skb_pull(skb, skb_network_offset(skb));
2188 res = run_filter(skb, sk, snaplen);
2190 goto drop_n_restore;
2192 if (skb->ip_summed == CHECKSUM_PARTIAL)
2193 status |= TP_STATUS_CSUMNOTREADY;
2194 else if (skb->pkt_type != PACKET_OUTGOING &&
2195 (skb->ip_summed == CHECKSUM_COMPLETE ||
2196 skb_csum_unnecessary(skb)))
2197 status |= TP_STATUS_CSUM_VALID;
2202 if (sk->sk_type == SOCK_DGRAM) {
2203 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2206 unsigned int maclen = skb_network_offset(skb);
2207 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2208 (maclen < 16 ? 16 : maclen)) +
2210 if (po->has_vnet_hdr) {
2211 netoff += sizeof(struct virtio_net_hdr);
2214 macoff = netoff - maclen;
2216 if (po->tp_version <= TPACKET_V2) {
2217 if (macoff + snaplen > po->rx_ring.frame_size) {
2218 if (po->copy_thresh &&
2219 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2220 if (skb_shared(skb)) {
2221 copy_skb = skb_clone(skb, GFP_ATOMIC);
2223 copy_skb = skb_get(skb);
2224 skb_head = skb->data;
2227 skb_set_owner_r(copy_skb, sk);
2229 snaplen = po->rx_ring.frame_size - macoff;
2230 if ((int)snaplen < 0) {
2235 } else if (unlikely(macoff + snaplen >
2236 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2239 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2240 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2241 snaplen, nval, macoff);
2243 if (unlikely((int)snaplen < 0)) {
2245 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2249 spin_lock(&sk->sk_receive_queue.lock);
2250 h.raw = packet_current_rx_frame(po, skb,
2251 TP_STATUS_KERNEL, (macoff+snaplen));
2253 goto drop_n_account;
2254 if (po->tp_version <= TPACKET_V2) {
2255 packet_increment_rx_head(po, &po->rx_ring);
2257 * LOSING will be reported till you read the stats,
2258 * because it's COR - Clear On Read.
2259 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2262 if (po->stats.stats1.tp_drops)
2263 status |= TP_STATUS_LOSING;
2267 virtio_net_hdr_from_skb(skb, h.raw + macoff -
2268 sizeof(struct virtio_net_hdr),
2270 goto drop_n_account;
2272 po->stats.stats1.tp_packets++;
2274 status |= TP_STATUS_COPY;
2275 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2277 spin_unlock(&sk->sk_receive_queue.lock);
2279 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2281 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2282 getnstimeofday(&ts);
2284 status |= ts_status;
2286 switch (po->tp_version) {
2288 h.h1->tp_len = skb->len;
2289 h.h1->tp_snaplen = snaplen;
2290 h.h1->tp_mac = macoff;
2291 h.h1->tp_net = netoff;
2292 h.h1->tp_sec = ts.tv_sec;
2293 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2294 hdrlen = sizeof(*h.h1);
2297 h.h2->tp_len = skb->len;
2298 h.h2->tp_snaplen = snaplen;
2299 h.h2->tp_mac = macoff;
2300 h.h2->tp_net = netoff;
2301 h.h2->tp_sec = ts.tv_sec;
2302 h.h2->tp_nsec = ts.tv_nsec;
2303 if (skb_vlan_tag_present(skb)) {
2304 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2305 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2306 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2308 h.h2->tp_vlan_tci = 0;
2309 h.h2->tp_vlan_tpid = 0;
2311 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2312 hdrlen = sizeof(*h.h2);
2315 /* tp_nxt_offset,vlan are already populated above.
2316 * So DONT clear those fields here
2318 h.h3->tp_status |= status;
2319 h.h3->tp_len = skb->len;
2320 h.h3->tp_snaplen = snaplen;
2321 h.h3->tp_mac = macoff;
2322 h.h3->tp_net = netoff;
2323 h.h3->tp_sec = ts.tv_sec;
2324 h.h3->tp_nsec = ts.tv_nsec;
2325 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2326 hdrlen = sizeof(*h.h3);
2332 sll = h.raw + TPACKET_ALIGN(hdrlen);
2333 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2334 sll->sll_family = AF_PACKET;
2335 sll->sll_hatype = dev->type;
2336 sll->sll_protocol = skb->protocol;
2337 sll->sll_pkttype = skb->pkt_type;
2338 if (unlikely(po->origdev))
2339 sll->sll_ifindex = orig_dev->ifindex;
2341 sll->sll_ifindex = dev->ifindex;
2345 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2346 if (po->tp_version <= TPACKET_V2) {
2349 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2352 for (start = h.raw; start < end; start += PAGE_SIZE)
2353 flush_dcache_page(pgv_to_page(start));
2358 if (po->tp_version <= TPACKET_V2) {
2359 __packet_set_status(po, h.raw, status);
2360 sk->sk_data_ready(sk);
2362 prb_clear_blk_fill_status(&po->rx_ring);
2366 if (skb_head != skb->data && skb_shared(skb)) {
2367 skb->data = skb_head;
2371 if (!is_drop_n_account)
2378 is_drop_n_account = true;
2379 po->stats.stats1.tp_drops++;
2380 spin_unlock(&sk->sk_receive_queue.lock);
2382 sk->sk_data_ready(sk);
2383 kfree_skb(copy_skb);
2384 goto drop_n_restore;
2387 static void tpacket_destruct_skb(struct sk_buff *skb)
2389 struct packet_sock *po = pkt_sk(skb->sk);
2391 if (likely(po->tx_ring.pg_vec)) {
2395 ph = skb_shinfo(skb)->destructor_arg;
2396 packet_dec_pending(&po->tx_ring);
2398 ts = __packet_set_timestamp(po, ph, skb);
2399 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2405 static void tpacket_set_protocol(const struct net_device *dev,
2406 struct sk_buff *skb)
2408 if (dev->type == ARPHRD_ETHER) {
2409 skb_reset_mac_header(skb);
2410 skb->protocol = eth_hdr(skb)->h_proto;
2414 static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2416 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2417 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2418 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2419 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2420 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2421 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2422 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2424 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2430 static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2431 struct virtio_net_hdr *vnet_hdr)
2433 if (*len < sizeof(*vnet_hdr))
2435 *len -= sizeof(*vnet_hdr);
2437 if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
2440 return __packet_snd_vnet_parse(vnet_hdr, *len);
2443 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2444 void *frame, struct net_device *dev, void *data, int tp_len,
2445 __be16 proto, unsigned char *addr, int hlen, int copylen,
2446 const struct sockcm_cookie *sockc)
2448 union tpacket_uhdr ph;
2449 int to_write, offset, len, nr_frags, len_max;
2450 struct socket *sock = po->sk.sk_socket;
2456 skb->protocol = proto;
2458 skb->priority = po->sk.sk_priority;
2459 skb->mark = po->sk.sk_mark;
2460 sock_tx_timestamp(&po->sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
2461 skb_shinfo(skb)->destructor_arg = ph.raw;
2463 skb_reserve(skb, hlen);
2464 skb_reset_network_header(skb);
2468 if (sock->type == SOCK_DGRAM) {
2469 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2471 if (unlikely(err < 0))
2473 } else if (copylen) {
2474 int hdrlen = min_t(int, copylen, tp_len);
2476 skb_push(skb, dev->hard_header_len);
2477 skb_put(skb, copylen - dev->hard_header_len);
2478 err = skb_store_bits(skb, 0, data, hdrlen);
2481 if (!dev_validate_header(dev, skb->data, hdrlen))
2484 tpacket_set_protocol(dev, skb);
2490 offset = offset_in_page(data);
2491 len_max = PAGE_SIZE - offset;
2492 len = ((to_write > len_max) ? len_max : to_write);
2494 skb->data_len = to_write;
2495 skb->len += to_write;
2496 skb->truesize += to_write;
2497 refcount_add(to_write, &po->sk.sk_wmem_alloc);
2499 while (likely(to_write)) {
2500 nr_frags = skb_shinfo(skb)->nr_frags;
2502 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2503 pr_err("Packet exceed the number of skb frags(%lu)\n",
2508 page = pgv_to_page(data);
2510 flush_dcache_page(page);
2512 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2515 len_max = PAGE_SIZE;
2516 len = ((to_write > len_max) ? len_max : to_write);
2519 skb_probe_transport_header(skb, 0);
2524 static int tpacket_parse_header(struct packet_sock *po, void *frame,
2525 int size_max, void **data)
2527 union tpacket_uhdr ph;
2532 switch (po->tp_version) {
2534 if (ph.h3->tp_next_offset != 0) {
2535 pr_warn_once("variable sized slot not supported");
2538 tp_len = ph.h3->tp_len;
2541 tp_len = ph.h2->tp_len;
2544 tp_len = ph.h1->tp_len;
2547 if (unlikely(tp_len > size_max)) {
2548 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2552 if (unlikely(po->tp_tx_has_off)) {
2553 int off_min, off_max;
2555 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2556 off_max = po->tx_ring.frame_size - tp_len;
2557 if (po->sk.sk_type == SOCK_DGRAM) {
2558 switch (po->tp_version) {
2560 off = ph.h3->tp_net;
2563 off = ph.h2->tp_net;
2566 off = ph.h1->tp_net;
2570 switch (po->tp_version) {
2572 off = ph.h3->tp_mac;
2575 off = ph.h2->tp_mac;
2578 off = ph.h1->tp_mac;
2582 if (unlikely((off < off_min) || (off_max < off)))
2585 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2588 *data = frame + off;
2592 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2594 struct sk_buff *skb;
2595 struct net_device *dev;
2596 struct virtio_net_hdr *vnet_hdr = NULL;
2597 struct sockcm_cookie sockc;
2599 int err, reserve = 0;
2601 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2602 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2603 int tp_len, size_max;
2604 unsigned char *addr;
2607 int status = TP_STATUS_AVAILABLE;
2608 int hlen, tlen, copylen = 0;
2610 mutex_lock(&po->pg_vec_lock);
2612 if (likely(saddr == NULL)) {
2613 dev = packet_cached_dev_get(po);
2618 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2620 if (msg->msg_namelen < (saddr->sll_halen
2621 + offsetof(struct sockaddr_ll,
2624 proto = saddr->sll_protocol;
2625 addr = saddr->sll_addr;
2626 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2630 if (unlikely(dev == NULL))
2633 if (unlikely(!(dev->flags & IFF_UP)))
2636 sockc.tsflags = po->sk.sk_tsflags;
2637 if (msg->msg_controllen) {
2638 err = sock_cmsg_send(&po->sk, msg, &sockc);
2643 if (po->sk.sk_socket->type == SOCK_RAW)
2644 reserve = dev->hard_header_len;
2645 size_max = po->tx_ring.frame_size
2646 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2648 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2649 size_max = dev->mtu + reserve + VLAN_HLEN;
2652 ph = packet_current_frame(po, &po->tx_ring,
2653 TP_STATUS_SEND_REQUEST);
2654 if (unlikely(ph == NULL)) {
2655 if (need_wait && need_resched())
2661 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2665 status = TP_STATUS_SEND_REQUEST;
2666 hlen = LL_RESERVED_SPACE(dev);
2667 tlen = dev->needed_tailroom;
2668 if (po->has_vnet_hdr) {
2670 data += sizeof(*vnet_hdr);
2671 tp_len -= sizeof(*vnet_hdr);
2673 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2677 copylen = __virtio16_to_cpu(vio_le(),
2680 copylen = max_t(int, copylen, dev->hard_header_len);
2681 skb = sock_alloc_send_skb(&po->sk,
2682 hlen + tlen + sizeof(struct sockaddr_ll) +
2683 (copylen - dev->hard_header_len),
2686 if (unlikely(skb == NULL)) {
2687 /* we assume the socket was initially writeable ... */
2688 if (likely(len_sum > 0))
2692 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2693 addr, hlen, copylen, &sockc);
2694 if (likely(tp_len >= 0) &&
2695 tp_len > dev->mtu + reserve &&
2696 !po->has_vnet_hdr &&
2697 !packet_extra_vlan_len_allowed(dev, skb))
2700 if (unlikely(tp_len < 0)) {
2703 __packet_set_status(po, ph,
2704 TP_STATUS_AVAILABLE);
2705 packet_increment_head(&po->tx_ring);
2709 status = TP_STATUS_WRONG_FORMAT;
2715 if (po->has_vnet_hdr && virtio_net_hdr_to_skb(skb, vnet_hdr,
2721 skb->destructor = tpacket_destruct_skb;
2722 __packet_set_status(po, ph, TP_STATUS_SENDING);
2723 packet_inc_pending(&po->tx_ring);
2725 status = TP_STATUS_SEND_REQUEST;
2726 err = po->xmit(skb);
2727 if (unlikely(err > 0)) {
2728 err = net_xmit_errno(err);
2729 if (err && __packet_get_status(po, ph) ==
2730 TP_STATUS_AVAILABLE) {
2731 /* skb was destructed already */
2736 * skb was dropped but not destructed yet;
2737 * let's treat it like congestion or err < 0
2741 packet_increment_head(&po->tx_ring);
2743 } while (likely((ph != NULL) ||
2744 /* Note: packet_read_pending() might be slow if we have
2745 * to call it as it's per_cpu variable, but in fast-path
2746 * we already short-circuit the loop with the first
2747 * condition, and luckily don't have to go that path
2750 (need_wait && packet_read_pending(&po->tx_ring))));
2756 __packet_set_status(po, ph, status);
2761 mutex_unlock(&po->pg_vec_lock);
2765 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2766 size_t reserve, size_t len,
2767 size_t linear, int noblock,
2770 struct sk_buff *skb;
2772 /* Under a page? Don't bother with paged skb. */
2773 if (prepad + len < PAGE_SIZE || !linear)
2776 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2781 skb_reserve(skb, reserve);
2782 skb_put(skb, linear);
2783 skb->data_len = len - linear;
2784 skb->len += len - linear;
2789 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2791 struct sock *sk = sock->sk;
2792 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2793 struct sk_buff *skb;
2794 struct net_device *dev;
2796 unsigned char *addr;
2797 int err, reserve = 0;
2798 struct sockcm_cookie sockc;
2799 struct virtio_net_hdr vnet_hdr = { 0 };
2801 struct packet_sock *po = pkt_sk(sk);
2802 bool has_vnet_hdr = false;
2803 int hlen, tlen, linear;
2807 * Get and verify the address.
2810 if (likely(saddr == NULL)) {
2811 dev = packet_cached_dev_get(po);
2816 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2818 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2820 proto = saddr->sll_protocol;
2821 addr = saddr->sll_addr;
2822 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2826 if (unlikely(dev == NULL))
2829 if (unlikely(!(dev->flags & IFF_UP)))
2832 sockc.tsflags = sk->sk_tsflags;
2833 sockc.mark = sk->sk_mark;
2834 if (msg->msg_controllen) {
2835 err = sock_cmsg_send(sk, msg, &sockc);
2840 if (sock->type == SOCK_RAW)
2841 reserve = dev->hard_header_len;
2842 if (po->has_vnet_hdr) {
2843 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2846 has_vnet_hdr = true;
2849 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2850 if (!netif_supports_nofcs(dev)) {
2851 err = -EPROTONOSUPPORT;
2854 extra_len = 4; /* We're doing our own CRC */
2858 if (!vnet_hdr.gso_type &&
2859 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2863 hlen = LL_RESERVED_SPACE(dev);
2864 tlen = dev->needed_tailroom;
2865 linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len);
2866 linear = max(linear, min_t(int, len, dev->hard_header_len));
2867 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear,
2868 msg->msg_flags & MSG_DONTWAIT, &err);
2872 skb_reset_network_header(skb);
2875 if (sock->type == SOCK_DGRAM) {
2876 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2877 if (unlikely(offset < 0))
2879 } else if (reserve) {
2880 skb_reserve(skb, -reserve);
2883 /* Returns -EFAULT on error */
2884 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2888 if (sock->type == SOCK_RAW &&
2889 !dev_validate_header(dev, skb->data, len)) {
2894 sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
2896 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
2897 !packet_extra_vlan_len_allowed(dev, skb)) {
2902 skb->protocol = proto;
2904 skb->priority = sk->sk_priority;
2905 skb->mark = sockc.mark;
2908 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
2911 len += sizeof(vnet_hdr);
2914 skb_probe_transport_header(skb, reserve);
2916 if (unlikely(extra_len == 4))
2919 err = po->xmit(skb);
2920 if (err > 0 && (err = net_xmit_errno(err)) != 0)
2936 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
2938 struct sock *sk = sock->sk;
2939 struct packet_sock *po = pkt_sk(sk);
2941 if (po->tx_ring.pg_vec)
2942 return tpacket_snd(po, msg);
2944 return packet_snd(sock, msg, len);
2948 * Close a PACKET socket. This is fairly simple. We immediately go
2949 * to 'closed' state and remove our protocol entry in the device list.
2952 static int packet_release(struct socket *sock)
2954 struct sock *sk = sock->sk;
2955 struct packet_sock *po;
2956 struct packet_fanout *f;
2958 union tpacket_req_u req_u;
2966 mutex_lock(&net->packet.sklist_lock);
2967 sk_del_node_init_rcu(sk);
2968 mutex_unlock(&net->packet.sklist_lock);
2971 sock_prot_inuse_add(net, sk->sk_prot, -1);
2974 spin_lock(&po->bind_lock);
2975 unregister_prot_hook(sk, false);
2976 packet_cached_dev_reset(po);
2978 if (po->prot_hook.dev) {
2979 dev_put(po->prot_hook.dev);
2980 po->prot_hook.dev = NULL;
2982 spin_unlock(&po->bind_lock);
2984 packet_flush_mclist(sk);
2987 if (po->rx_ring.pg_vec) {
2988 memset(&req_u, 0, sizeof(req_u));
2989 packet_set_ring(sk, &req_u, 1, 0);
2992 if (po->tx_ring.pg_vec) {
2993 memset(&req_u, 0, sizeof(req_u));
2994 packet_set_ring(sk, &req_u, 1, 1);
2998 f = fanout_release(sk);
3003 kfree(po->rollover);
3004 fanout_release_data(f);
3008 * Now the socket is dead. No more input will appear.
3015 skb_queue_purge(&sk->sk_receive_queue);
3016 packet_free_pending(po);
3017 sk_refcnt_debug_release(sk);
3024 * Attach a packet hook.
3027 static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3030 struct packet_sock *po = pkt_sk(sk);
3031 struct net_device *dev_curr;
3034 struct net_device *dev = NULL;
3036 bool unlisted = false;
3039 spin_lock(&po->bind_lock);
3048 dev = dev_get_by_name_rcu(sock_net(sk), name);
3053 } else if (ifindex) {
3054 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3064 proto_curr = po->prot_hook.type;
3065 dev_curr = po->prot_hook.dev;
3067 need_rehook = proto_curr != proto || dev_curr != dev;
3072 /* prevents packet_notifier() from calling
3073 * register_prot_hook()
3076 __unregister_prot_hook(sk, true);
3078 dev_curr = po->prot_hook.dev;
3080 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3084 BUG_ON(po->running);
3086 po->prot_hook.type = proto;
3088 if (unlikely(unlisted)) {
3090 po->prot_hook.dev = NULL;
3092 packet_cached_dev_reset(po);
3094 po->prot_hook.dev = dev;
3095 po->ifindex = dev ? dev->ifindex : 0;
3096 packet_cached_dev_assign(po, dev);
3102 if (proto == 0 || !need_rehook)
3105 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3106 register_prot_hook(sk);
3108 sk->sk_err = ENETDOWN;
3109 if (!sock_flag(sk, SOCK_DEAD))
3110 sk->sk_error_report(sk);
3115 spin_unlock(&po->bind_lock);
3121 * Bind a packet socket to a device
3124 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3127 struct sock *sk = sock->sk;
3128 char name[sizeof(uaddr->sa_data) + 1];
3134 if (addr_len != sizeof(struct sockaddr))
3136 /* uaddr->sa_data comes from the userspace, it's not guaranteed to be
3139 memcpy(name, uaddr->sa_data, sizeof(uaddr->sa_data));
3140 name[sizeof(uaddr->sa_data)] = 0;
3142 return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3145 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3147 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3148 struct sock *sk = sock->sk;
3154 if (addr_len < sizeof(struct sockaddr_ll))
3156 if (sll->sll_family != AF_PACKET)
3159 return packet_do_bind(sk, NULL, sll->sll_ifindex,
3160 sll->sll_protocol ? : pkt_sk(sk)->num);
3163 static struct proto packet_proto = {
3165 .owner = THIS_MODULE,
3166 .obj_size = sizeof(struct packet_sock),
3170 * Create a packet of type SOCK_PACKET.
3173 static int packet_create(struct net *net, struct socket *sock, int protocol,
3177 struct packet_sock *po;
3178 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3181 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3183 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3184 sock->type != SOCK_PACKET)
3185 return -ESOCKTNOSUPPORT;
3187 sock->state = SS_UNCONNECTED;
3190 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3194 sock->ops = &packet_ops;
3195 if (sock->type == SOCK_PACKET)
3196 sock->ops = &packet_ops_spkt;
3198 sock_init_data(sock, sk);
3201 sk->sk_family = PF_PACKET;
3203 po->xmit = dev_queue_xmit;
3205 err = packet_alloc_pending(po);
3209 packet_cached_dev_reset(po);
3211 sk->sk_destruct = packet_sock_destruct;
3212 sk_refcnt_debug_inc(sk);
3215 * Attach a protocol block
3218 spin_lock_init(&po->bind_lock);
3219 mutex_init(&po->pg_vec_lock);
3220 po->rollover = NULL;
3221 po->prot_hook.func = packet_rcv;
3223 if (sock->type == SOCK_PACKET)
3224 po->prot_hook.func = packet_rcv_spkt;
3226 po->prot_hook.af_packet_priv = sk;
3229 po->prot_hook.type = proto;
3230 __register_prot_hook(sk);
3233 mutex_lock(&net->packet.sklist_lock);
3234 sk_add_node_rcu(sk, &net->packet.sklist);
3235 mutex_unlock(&net->packet.sklist_lock);
3238 sock_prot_inuse_add(net, &packet_proto, 1);
3249 * Pull a packet from our receive queue and hand it to the user.
3250 * If necessary we block.
3253 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3256 struct sock *sk = sock->sk;
3257 struct sk_buff *skb;
3259 int vnet_hdr_len = 0;
3260 unsigned int origlen = 0;
3263 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3267 /* What error should we return now? EUNATTACH? */
3268 if (pkt_sk(sk)->ifindex < 0)
3272 if (flags & MSG_ERRQUEUE) {
3273 err = sock_recv_errqueue(sk, msg, len,
3274 SOL_PACKET, PACKET_TX_TIMESTAMP);
3279 * Call the generic datagram receiver. This handles all sorts
3280 * of horrible races and re-entrancy so we can forget about it
3281 * in the protocol layers.
3283 * Now it will return ENETDOWN, if device have just gone down,
3284 * but then it will block.
3287 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3290 * An error occurred so return it. Because skb_recv_datagram()
3291 * handles the blocking we don't see and worry about blocking
3298 if (pkt_sk(sk)->pressure)
3299 packet_rcv_has_room(pkt_sk(sk), NULL);
3301 if (pkt_sk(sk)->has_vnet_hdr) {
3302 err = packet_rcv_vnet(msg, skb, &len);
3305 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3308 /* You lose any data beyond the buffer you gave. If it worries
3309 * a user program they can ask the device for its MTU
3315 msg->msg_flags |= MSG_TRUNC;
3318 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3322 if (sock->type != SOCK_PACKET) {
3323 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3325 /* Original length was stored in sockaddr_ll fields */
3326 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3327 sll->sll_family = AF_PACKET;
3328 sll->sll_protocol = skb->protocol;
3331 sock_recv_ts_and_drops(msg, sk, skb);
3333 if (msg->msg_name) {
3334 /* If the address length field is there to be filled
3335 * in, we fill it in now.
3337 if (sock->type == SOCK_PACKET) {
3338 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3339 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3341 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3343 msg->msg_namelen = sll->sll_halen +
3344 offsetof(struct sockaddr_ll, sll_addr);
3346 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
3350 if (pkt_sk(sk)->auxdata) {
3351 struct tpacket_auxdata aux;
3353 aux.tp_status = TP_STATUS_USER;
3354 if (skb->ip_summed == CHECKSUM_PARTIAL)
3355 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3356 else if (skb->pkt_type != PACKET_OUTGOING &&
3357 (skb->ip_summed == CHECKSUM_COMPLETE ||
3358 skb_csum_unnecessary(skb)))
3359 aux.tp_status |= TP_STATUS_CSUM_VALID;
3361 aux.tp_len = origlen;
3362 aux.tp_snaplen = skb->len;
3364 aux.tp_net = skb_network_offset(skb);
3365 if (skb_vlan_tag_present(skb)) {
3366 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3367 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3368 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3370 aux.tp_vlan_tci = 0;
3371 aux.tp_vlan_tpid = 0;
3373 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3377 * Free or return the buffer as appropriate. Again this
3378 * hides all the races and re-entrancy issues from us.
3380 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3383 skb_free_datagram(sk, skb);
3388 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3391 struct net_device *dev;
3392 struct sock *sk = sock->sk;
3397 uaddr->sa_family = AF_PACKET;
3398 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3400 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3402 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3405 return sizeof(*uaddr);
3408 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3411 struct net_device *dev;
3412 struct sock *sk = sock->sk;
3413 struct packet_sock *po = pkt_sk(sk);
3414 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3419 sll->sll_family = AF_PACKET;
3420 sll->sll_ifindex = po->ifindex;
3421 sll->sll_protocol = po->num;
3422 sll->sll_pkttype = 0;
3424 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3426 sll->sll_hatype = dev->type;
3427 sll->sll_halen = dev->addr_len;
3428 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3430 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3435 return offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3438 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3442 case PACKET_MR_MULTICAST:
3443 if (i->alen != dev->addr_len)
3446 return dev_mc_add(dev, i->addr);
3448 return dev_mc_del(dev, i->addr);
3450 case PACKET_MR_PROMISC:
3451 return dev_set_promiscuity(dev, what);
3452 case PACKET_MR_ALLMULTI:
3453 return dev_set_allmulti(dev, what);
3454 case PACKET_MR_UNICAST:
3455 if (i->alen != dev->addr_len)
3458 return dev_uc_add(dev, i->addr);
3460 return dev_uc_del(dev, i->addr);
3468 static void packet_dev_mclist_delete(struct net_device *dev,
3469 struct packet_mclist **mlp)
3471 struct packet_mclist *ml;
3473 while ((ml = *mlp) != NULL) {
3474 if (ml->ifindex == dev->ifindex) {
3475 packet_dev_mc(dev, ml, -1);
3483 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3485 struct packet_sock *po = pkt_sk(sk);
3486 struct packet_mclist *ml, *i;
3487 struct net_device *dev;
3493 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3498 if (mreq->mr_alen > dev->addr_len)
3502 i = kmalloc(sizeof(*i), GFP_KERNEL);
3507 for (ml = po->mclist; ml; ml = ml->next) {
3508 if (ml->ifindex == mreq->mr_ifindex &&
3509 ml->type == mreq->mr_type &&
3510 ml->alen == mreq->mr_alen &&
3511 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3513 /* Free the new element ... */
3519 i->type = mreq->mr_type;
3520 i->ifindex = mreq->mr_ifindex;
3521 i->alen = mreq->mr_alen;
3522 memcpy(i->addr, mreq->mr_address, i->alen);
3523 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3525 i->next = po->mclist;
3527 err = packet_dev_mc(dev, i, 1);
3529 po->mclist = i->next;
3538 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3540 struct packet_mclist *ml, **mlp;
3544 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3545 if (ml->ifindex == mreq->mr_ifindex &&
3546 ml->type == mreq->mr_type &&
3547 ml->alen == mreq->mr_alen &&
3548 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3549 if (--ml->count == 0) {
3550 struct net_device *dev;
3552 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3554 packet_dev_mc(dev, ml, -1);
3564 static void packet_flush_mclist(struct sock *sk)
3566 struct packet_sock *po = pkt_sk(sk);
3567 struct packet_mclist *ml;
3573 while ((ml = po->mclist) != NULL) {
3574 struct net_device *dev;
3576 po->mclist = ml->next;
3577 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3579 packet_dev_mc(dev, ml, -1);
3586 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3588 struct sock *sk = sock->sk;
3589 struct packet_sock *po = pkt_sk(sk);
3592 if (level != SOL_PACKET)
3593 return -ENOPROTOOPT;
3596 case PACKET_ADD_MEMBERSHIP:
3597 case PACKET_DROP_MEMBERSHIP:
3599 struct packet_mreq_max mreq;
3601 memset(&mreq, 0, sizeof(mreq));
3602 if (len < sizeof(struct packet_mreq))
3604 if (len > sizeof(mreq))
3606 if (copy_from_user(&mreq, optval, len))
3608 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3610 if (optname == PACKET_ADD_MEMBERSHIP)
3611 ret = packet_mc_add(sk, &mreq);
3613 ret = packet_mc_drop(sk, &mreq);
3617 case PACKET_RX_RING:
3618 case PACKET_TX_RING:
3620 union tpacket_req_u req_u;
3624 switch (po->tp_version) {
3627 len = sizeof(req_u.req);
3631 len = sizeof(req_u.req3);
3637 if (copy_from_user(&req_u.req, optval, len))
3640 ret = packet_set_ring(sk, &req_u, 0,
3641 optname == PACKET_TX_RING);
3646 case PACKET_COPY_THRESH:
3650 if (optlen != sizeof(val))
3652 if (copy_from_user(&val, optval, sizeof(val)))
3655 pkt_sk(sk)->copy_thresh = val;
3658 case PACKET_VERSION:
3662 if (optlen != sizeof(val))
3664 if (copy_from_user(&val, optval, sizeof(val)))
3675 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3678 po->tp_version = val;
3684 case PACKET_RESERVE:
3688 if (optlen != sizeof(val))
3690 if (copy_from_user(&val, optval, sizeof(val)))
3695 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3698 po->tp_reserve = val;
3708 if (optlen != sizeof(val))
3710 if (copy_from_user(&val, optval, sizeof(val)))
3714 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3717 po->tp_loss = !!val;
3723 case PACKET_AUXDATA:
3727 if (optlen < sizeof(val))
3729 if (copy_from_user(&val, optval, sizeof(val)))
3733 po->auxdata = !!val;
3737 case PACKET_ORIGDEV:
3741 if (optlen < sizeof(val))
3743 if (copy_from_user(&val, optval, sizeof(val)))
3747 po->origdev = !!val;
3751 case PACKET_VNET_HDR:
3755 if (sock->type != SOCK_RAW)
3757 if (optlen < sizeof(val))
3759 if (copy_from_user(&val, optval, sizeof(val)))
3763 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3766 po->has_vnet_hdr = !!val;
3772 case PACKET_TIMESTAMP:
3776 if (optlen != sizeof(val))
3778 if (copy_from_user(&val, optval, sizeof(val)))
3781 po->tp_tstamp = val;
3788 if (optlen != sizeof(val))
3790 if (copy_from_user(&val, optval, sizeof(val)))
3793 return fanout_add(sk, val & 0xffff, val >> 16);
3795 case PACKET_FANOUT_DATA:
3800 return fanout_set_data(po, optval, optlen);
3802 case PACKET_TX_HAS_OFF:
3806 if (optlen != sizeof(val))
3808 if (copy_from_user(&val, optval, sizeof(val)))
3812 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3815 po->tp_tx_has_off = !!val;
3821 case PACKET_QDISC_BYPASS:
3825 if (optlen != sizeof(val))
3827 if (copy_from_user(&val, optval, sizeof(val)))
3830 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3834 return -ENOPROTOOPT;
3838 static int packet_getsockopt(struct socket *sock, int level, int optname,
3839 char __user *optval, int __user *optlen)
3842 int val, lv = sizeof(val);
3843 struct sock *sk = sock->sk;
3844 struct packet_sock *po = pkt_sk(sk);
3846 union tpacket_stats_u st;
3847 struct tpacket_rollover_stats rstats;
3849 if (level != SOL_PACKET)
3850 return -ENOPROTOOPT;
3852 if (get_user(len, optlen))
3859 case PACKET_STATISTICS:
3860 spin_lock_bh(&sk->sk_receive_queue.lock);
3861 memcpy(&st, &po->stats, sizeof(st));
3862 memset(&po->stats, 0, sizeof(po->stats));
3863 spin_unlock_bh(&sk->sk_receive_queue.lock);
3865 if (po->tp_version == TPACKET_V3) {
3866 lv = sizeof(struct tpacket_stats_v3);
3867 st.stats3.tp_packets += st.stats3.tp_drops;
3870 lv = sizeof(struct tpacket_stats);
3871 st.stats1.tp_packets += st.stats1.tp_drops;
3876 case PACKET_AUXDATA:
3879 case PACKET_ORIGDEV:
3882 case PACKET_VNET_HDR:
3883 val = po->has_vnet_hdr;
3885 case PACKET_VERSION:
3886 val = po->tp_version;
3889 if (len > sizeof(int))
3891 if (len < sizeof(int))
3893 if (copy_from_user(&val, optval, len))
3897 val = sizeof(struct tpacket_hdr);
3900 val = sizeof(struct tpacket2_hdr);
3903 val = sizeof(struct tpacket3_hdr);
3909 case PACKET_RESERVE:
3910 val = po->tp_reserve;
3915 case PACKET_TIMESTAMP:
3916 val = po->tp_tstamp;
3920 ((u32)po->fanout->id |
3921 ((u32)po->fanout->type << 16) |
3922 ((u32)po->fanout->flags << 24)) :
3925 case PACKET_ROLLOVER_STATS:
3928 rstats.tp_all = atomic_long_read(&po->rollover->num);
3929 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
3930 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
3932 lv = sizeof(rstats);
3934 case PACKET_TX_HAS_OFF:
3935 val = po->tp_tx_has_off;
3937 case PACKET_QDISC_BYPASS:
3938 val = packet_use_direct_xmit(po);
3941 return -ENOPROTOOPT;
3946 if (put_user(len, optlen))
3948 if (copy_to_user(optval, data, len))
3954 #ifdef CONFIG_COMPAT
3955 static int compat_packet_setsockopt(struct socket *sock, int level, int optname,
3956 char __user *optval, unsigned int optlen)
3958 struct packet_sock *po = pkt_sk(sock->sk);
3960 if (level != SOL_PACKET)
3961 return -ENOPROTOOPT;
3963 if (optname == PACKET_FANOUT_DATA &&
3964 po->fanout && po->fanout->type == PACKET_FANOUT_CBPF) {
3965 optval = (char __user *)get_compat_bpf_fprog(optval);
3968 optlen = sizeof(struct sock_fprog);
3971 return packet_setsockopt(sock, level, optname, optval, optlen);
3975 static int packet_notifier(struct notifier_block *this,
3976 unsigned long msg, void *ptr)
3979 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3980 struct net *net = dev_net(dev);
3983 sk_for_each_rcu(sk, &net->packet.sklist) {
3984 struct packet_sock *po = pkt_sk(sk);
3987 case NETDEV_UNREGISTER:
3989 packet_dev_mclist_delete(dev, &po->mclist);
3993 if (dev->ifindex == po->ifindex) {
3994 spin_lock(&po->bind_lock);
3996 __unregister_prot_hook(sk, false);
3997 sk->sk_err = ENETDOWN;
3998 if (!sock_flag(sk, SOCK_DEAD))
3999 sk->sk_error_report(sk);
4001 if (msg == NETDEV_UNREGISTER) {
4002 packet_cached_dev_reset(po);
4004 if (po->prot_hook.dev)
4005 dev_put(po->prot_hook.dev);
4006 po->prot_hook.dev = NULL;
4008 spin_unlock(&po->bind_lock);
4012 if (dev->ifindex == po->ifindex) {
4013 spin_lock(&po->bind_lock);
4015 register_prot_hook(sk);
4016 spin_unlock(&po->bind_lock);
4026 static int packet_ioctl(struct socket *sock, unsigned int cmd,
4029 struct sock *sk = sock->sk;
4034 int amount = sk_wmem_alloc_get(sk);
4036 return put_user(amount, (int __user *)arg);
4040 struct sk_buff *skb;
4043 spin_lock_bh(&sk->sk_receive_queue.lock);
4044 skb = skb_peek(&sk->sk_receive_queue);
4047 spin_unlock_bh(&sk->sk_receive_queue.lock);
4048 return put_user(amount, (int __user *)arg);
4051 return sock_get_timestamp(sk, (struct timeval __user *)arg);
4053 return sock_get_timestampns(sk, (struct timespec __user *)arg);
4063 case SIOCGIFBRDADDR:
4064 case SIOCSIFBRDADDR:
4065 case SIOCGIFNETMASK:
4066 case SIOCSIFNETMASK:
4067 case SIOCGIFDSTADDR:
4068 case SIOCSIFDSTADDR:
4070 return inet_dgram_ops.ioctl(sock, cmd, arg);
4074 return -ENOIOCTLCMD;
4079 static __poll_t packet_poll(struct file *file, struct socket *sock,
4082 struct sock *sk = sock->sk;
4083 struct packet_sock *po = pkt_sk(sk);
4084 __poll_t mask = datagram_poll(file, sock, wait);
4086 spin_lock_bh(&sk->sk_receive_queue.lock);
4087 if (po->rx_ring.pg_vec) {
4088 if (!packet_previous_rx_frame(po, &po->rx_ring,
4090 mask |= EPOLLIN | EPOLLRDNORM;
4092 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
4094 spin_unlock_bh(&sk->sk_receive_queue.lock);
4095 spin_lock_bh(&sk->sk_write_queue.lock);
4096 if (po->tx_ring.pg_vec) {
4097 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4098 mask |= EPOLLOUT | EPOLLWRNORM;
4100 spin_unlock_bh(&sk->sk_write_queue.lock);
4105 /* Dirty? Well, I still did not learn better way to account
4109 static void packet_mm_open(struct vm_area_struct *vma)
4111 struct file *file = vma->vm_file;
4112 struct socket *sock = file->private_data;
4113 struct sock *sk = sock->sk;
4116 atomic_inc(&pkt_sk(sk)->mapped);
4119 static void packet_mm_close(struct vm_area_struct *vma)
4121 struct file *file = vma->vm_file;
4122 struct socket *sock = file->private_data;
4123 struct sock *sk = sock->sk;
4126 atomic_dec(&pkt_sk(sk)->mapped);
4129 static const struct vm_operations_struct packet_mmap_ops = {
4130 .open = packet_mm_open,
4131 .close = packet_mm_close,
4134 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4139 for (i = 0; i < len; i++) {
4140 if (likely(pg_vec[i].buffer)) {
4141 if (is_vmalloc_addr(pg_vec[i].buffer))
4142 vfree(pg_vec[i].buffer);
4144 free_pages((unsigned long)pg_vec[i].buffer,
4146 pg_vec[i].buffer = NULL;
4152 static char *alloc_one_pg_vec_page(unsigned long order)
4155 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4156 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4158 buffer = (char *) __get_free_pages(gfp_flags, order);
4162 /* __get_free_pages failed, fall back to vmalloc */
4163 buffer = vzalloc(array_size((1 << order), PAGE_SIZE));
4167 /* vmalloc failed, lets dig into swap here */
4168 gfp_flags &= ~__GFP_NORETRY;
4169 buffer = (char *) __get_free_pages(gfp_flags, order);
4173 /* complete and utter failure */
4177 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4179 unsigned int block_nr = req->tp_block_nr;
4183 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4184 if (unlikely(!pg_vec))
4187 for (i = 0; i < block_nr; i++) {
4188 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4189 if (unlikely(!pg_vec[i].buffer))
4190 goto out_free_pgvec;
4197 free_pg_vec(pg_vec, order, block_nr);
4202 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4203 int closing, int tx_ring)
4205 struct pgv *pg_vec = NULL;
4206 struct packet_sock *po = pkt_sk(sk);
4207 int was_running, order = 0;
4208 struct packet_ring_buffer *rb;
4209 struct sk_buff_head *rb_queue;
4212 /* Added to avoid minimal code churn */
4213 struct tpacket_req *req = &req_u->req;
4215 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4216 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4220 if (atomic_read(&po->mapped))
4222 if (packet_read_pending(rb))
4226 if (req->tp_block_nr) {
4227 /* Sanity tests and some calculations */
4229 if (unlikely(rb->pg_vec))
4232 switch (po->tp_version) {
4234 po->tp_hdrlen = TPACKET_HDRLEN;
4237 po->tp_hdrlen = TPACKET2_HDRLEN;
4240 po->tp_hdrlen = TPACKET3_HDRLEN;
4245 if (unlikely((int)req->tp_block_size <= 0))
4247 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4249 if (po->tp_version >= TPACKET_V3 &&
4250 req->tp_block_size <=
4251 BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv) + sizeof(struct tpacket3_hdr))
4253 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
4256 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4259 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4260 if (unlikely(rb->frames_per_block == 0))
4262 if (unlikely(req->tp_block_size > UINT_MAX / req->tp_block_nr))
4264 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4269 order = get_order(req->tp_block_size);
4270 pg_vec = alloc_pg_vec(req, order);
4271 if (unlikely(!pg_vec))
4273 switch (po->tp_version) {
4275 /* Block transmit is not supported yet */
4277 init_prb_bdqc(po, rb, pg_vec, req_u);
4279 struct tpacket_req3 *req3 = &req_u->req3;
4281 if (req3->tp_retire_blk_tov ||
4282 req3->tp_sizeof_priv ||
4283 req3->tp_feature_req_word) {
4296 if (unlikely(req->tp_frame_nr))
4301 /* Detach socket from network */
4302 spin_lock(&po->bind_lock);
4303 was_running = po->running;
4307 __unregister_prot_hook(sk, false);
4309 spin_unlock(&po->bind_lock);
4314 mutex_lock(&po->pg_vec_lock);
4315 if (closing || atomic_read(&po->mapped) == 0) {
4317 spin_lock_bh(&rb_queue->lock);
4318 swap(rb->pg_vec, pg_vec);
4319 rb->frame_max = (req->tp_frame_nr - 1);
4321 rb->frame_size = req->tp_frame_size;
4322 spin_unlock_bh(&rb_queue->lock);
4324 swap(rb->pg_vec_order, order);
4325 swap(rb->pg_vec_len, req->tp_block_nr);
4327 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4328 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4329 tpacket_rcv : packet_rcv;
4330 skb_queue_purge(rb_queue);
4331 if (atomic_read(&po->mapped))
4332 pr_err("packet_mmap: vma is busy: %d\n",
4333 atomic_read(&po->mapped));
4335 mutex_unlock(&po->pg_vec_lock);
4337 spin_lock(&po->bind_lock);
4340 register_prot_hook(sk);
4342 spin_unlock(&po->bind_lock);
4343 if (pg_vec && (po->tp_version > TPACKET_V2)) {
4344 /* Because we don't support block-based V3 on tx-ring */
4346 prb_shutdown_retire_blk_timer(po, rb_queue);
4350 free_pg_vec(pg_vec, order, req->tp_block_nr);
4355 static int packet_mmap(struct file *file, struct socket *sock,
4356 struct vm_area_struct *vma)
4358 struct sock *sk = sock->sk;
4359 struct packet_sock *po = pkt_sk(sk);
4360 unsigned long size, expected_size;
4361 struct packet_ring_buffer *rb;
4362 unsigned long start;
4369 mutex_lock(&po->pg_vec_lock);
4372 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4374 expected_size += rb->pg_vec_len
4380 if (expected_size == 0)
4383 size = vma->vm_end - vma->vm_start;
4384 if (size != expected_size)
4387 start = vma->vm_start;
4388 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4389 if (rb->pg_vec == NULL)
4392 for (i = 0; i < rb->pg_vec_len; i++) {
4394 void *kaddr = rb->pg_vec[i].buffer;
4397 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4398 page = pgv_to_page(kaddr);
4399 err = vm_insert_page(vma, start, page);
4408 atomic_inc(&po->mapped);
4409 vma->vm_ops = &packet_mmap_ops;
4413 mutex_unlock(&po->pg_vec_lock);
4417 static const struct proto_ops packet_ops_spkt = {
4418 .family = PF_PACKET,
4419 .owner = THIS_MODULE,
4420 .release = packet_release,
4421 .bind = packet_bind_spkt,
4422 .connect = sock_no_connect,
4423 .socketpair = sock_no_socketpair,
4424 .accept = sock_no_accept,
4425 .getname = packet_getname_spkt,
4426 .poll = datagram_poll,
4427 .ioctl = packet_ioctl,
4428 .listen = sock_no_listen,
4429 .shutdown = sock_no_shutdown,
4430 .setsockopt = sock_no_setsockopt,
4431 .getsockopt = sock_no_getsockopt,
4432 .sendmsg = packet_sendmsg_spkt,
4433 .recvmsg = packet_recvmsg,
4434 .mmap = sock_no_mmap,
4435 .sendpage = sock_no_sendpage,
4438 static const struct proto_ops packet_ops = {
4439 .family = PF_PACKET,
4440 .owner = THIS_MODULE,
4441 .release = packet_release,
4442 .bind = packet_bind,
4443 .connect = sock_no_connect,
4444 .socketpair = sock_no_socketpair,
4445 .accept = sock_no_accept,
4446 .getname = packet_getname,
4447 .poll = packet_poll,
4448 .ioctl = packet_ioctl,
4449 .listen = sock_no_listen,
4450 .shutdown = sock_no_shutdown,
4451 .setsockopt = packet_setsockopt,
4452 .getsockopt = packet_getsockopt,
4453 #ifdef CONFIG_COMPAT
4454 .compat_setsockopt = compat_packet_setsockopt,
4456 .sendmsg = packet_sendmsg,
4457 .recvmsg = packet_recvmsg,
4458 .mmap = packet_mmap,
4459 .sendpage = sock_no_sendpage,
4462 static const struct net_proto_family packet_family_ops = {
4463 .family = PF_PACKET,
4464 .create = packet_create,
4465 .owner = THIS_MODULE,
4468 static struct notifier_block packet_netdev_notifier = {
4469 .notifier_call = packet_notifier,
4472 #ifdef CONFIG_PROC_FS
4474 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4477 struct net *net = seq_file_net(seq);
4480 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4483 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4485 struct net *net = seq_file_net(seq);
4486 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4489 static void packet_seq_stop(struct seq_file *seq, void *v)
4495 static int packet_seq_show(struct seq_file *seq, void *v)
4497 if (v == SEQ_START_TOKEN)
4498 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
4500 struct sock *s = sk_entry(v);
4501 const struct packet_sock *po = pkt_sk(s);
4504 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4506 refcount_read(&s->sk_refcnt),
4511 atomic_read(&s->sk_rmem_alloc),
4512 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4519 static const struct seq_operations packet_seq_ops = {
4520 .start = packet_seq_start,
4521 .next = packet_seq_next,
4522 .stop = packet_seq_stop,
4523 .show = packet_seq_show,
4527 static int __net_init packet_net_init(struct net *net)
4529 mutex_init(&net->packet.sklist_lock);
4530 INIT_HLIST_HEAD(&net->packet.sklist);
4532 if (!proc_create_net("packet", 0, net->proc_net, &packet_seq_ops,
4533 sizeof(struct seq_net_private)))
4539 static void __net_exit packet_net_exit(struct net *net)
4541 remove_proc_entry("packet", net->proc_net);
4542 WARN_ON_ONCE(!hlist_empty(&net->packet.sklist));
4545 static struct pernet_operations packet_net_ops = {
4546 .init = packet_net_init,
4547 .exit = packet_net_exit,
4551 static void __exit packet_exit(void)
4553 unregister_netdevice_notifier(&packet_netdev_notifier);
4554 unregister_pernet_subsys(&packet_net_ops);
4555 sock_unregister(PF_PACKET);
4556 proto_unregister(&packet_proto);
4559 static int __init packet_init(void)
4561 int rc = proto_register(&packet_proto, 0);
4566 sock_register(&packet_family_ops);
4567 register_pernet_subsys(&packet_net_ops);
4568 register_netdevice_notifier(&packet_netdev_notifier);
4573 module_init(packet_init);
4574 module_exit(packet_exit);
4575 MODULE_LICENSE("GPL");
4576 MODULE_ALIAS_NETPROTO(PF_PACKET);